From: Li Lingfeng lilingfeng3@huawei.com

Offering: HULK hulk inclusion category: feature bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC

-------------------------------

This reverts commit ac02c0bf87ea4b239663211a3984c8d8b3a98be0.

We need to apply patch 788d0824269bef (io_uring: import 5.15-stable io_uring) to move io_uring to separate directory and solve the problem of CVE-2023-0240. Revert this patch and add it again after patch 788d0824269bef to reduce conflicts.

Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/io_uring.c | 3 --- 1 file changed, 3 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c index adb8fcef738a..2397c2a1d919 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -6705,9 +6705,6 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) err = io_submit_sqe(req, sqe, &link, &state.comp); if (err) goto fail_req; - /* to avoid doing too much in one submit round */ - if (submitted > IORING_MAX_ENTRIES / 2) - cond_resched(); }

if (unlikely(submitted != nr)) {

From: Li Lingfeng lilingfeng3@huawei.com

Offering: HULK hulk inclusion category: feature bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC

-------------------------------

This reverts commit da4cb34620205862e9fb4643fda239a223a1e3d3.

We need to apply patch 788d0824269bef (io_uring: import 5.15-stable io_uring) to move io_uring to separate directory and solve the problem of CVE-2023-0240. This patch can be reverted since patch 788d0824269bef contains it.

Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/io_uring.c | 14 +++----------- 1 file changed, 3 insertions(+), 11 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c index 2397c2a1d919..472bcea45bc8 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1718,22 +1718,18 @@ static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force, return cqe != NULL; }

-static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force, +static void io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force, struct task_struct *tsk, struct files_struct *files) { - bool ret = true; - if (test_bit(0, &ctx->cq_check_overflow)) { /* iopoll syncs against uring_lock, not completion_lock */ if (ctx->flags & IORING_SETUP_IOPOLL) mutex_lock(&ctx->uring_lock); - ret = __io_cqring_overflow_flush(ctx, force, tsk, files); + __io_cqring_overflow_flush(ctx, force, tsk, files); if (ctx->flags & IORING_SETUP_IOPOLL) mutex_unlock(&ctx->uring_lock); } - - return ret; }

static void __io_cqring_fill_event(struct io_kiocb *req, long res, @@ -7035,11 +7031,7 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts); trace_io_uring_cqring_wait(ctx, min_events); do { - /* if we can't even flush overflow, don't wait for more */ - if (!io_cqring_overflow_flush(ctx, false, NULL, NULL)) { - ret = -EBUSY; - break; - } + io_cqring_overflow_flush(ctx, false, NULL, NULL); prepare_to_wait_exclusive(&ctx->wait, &iowq.wq, TASK_INTERRUPTIBLE); /* make sure we run task_work before checking for signals */

From: Li Lingfeng lilingfeng3@huawei.com

Offering: HULK hulk inclusion category: feature bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC

-------------------------------

This reverts commit 62ca17101210b51f98146f7502ae25238c69f4a6.

This patch extracts a function for patch 792bb6eb8623 (io_uring: don't take uring_lock during iowq cancel). We can revert it since patch 792bb6eb8623 has been replaced by the one from stable/5.10.

Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/io_uring.c | 46 +++++++++++++++++++++++++++++----------------- 1 file changed, 29 insertions(+), 17 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c index a879bf985883..942883c16c3b 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -2073,16 +2073,6 @@ static int io_req_task_work_add(struct io_kiocb *req, bool twa_signal_ok) return ret; }

-static void io_req_task_work_add_fallback(struct io_kiocb *req, - void (*cb)(struct callback_head *)) -{ - struct task_struct *tsk = io_wq_get_task(req->ctx->io_wq); - - init_task_work(&req->task_work, cb); - task_work_add(tsk, &req->task_work, TWA_NONE); - wake_up_process(tsk); -} - static void __io_req_task_cancel(struct io_kiocb *req, int error) { struct io_ring_ctx *ctx = req->ctx; @@ -2138,8 +2128,14 @@ static void io_req_task_queue(struct io_kiocb *req) percpu_ref_get(&req->ctx->refs);

ret = io_req_task_work_add(req, true); - if (unlikely(ret)) - io_req_task_work_add_fallback(req, io_req_task_cancel); + if (unlikely(ret)) { + struct task_struct *tsk; + + init_task_work(&req->task_work, io_req_task_cancel); + tsk = io_wq_get_task(req->ctx->io_wq); + task_work_add(tsk, &req->task_work, TWA_NONE); + wake_up_process(tsk); + } }

static void io_queue_next(struct io_kiocb *req) @@ -2258,8 +2254,13 @@ static void io_free_req_deferred(struct io_kiocb *req)

init_task_work(&req->task_work, io_put_req_deferred_cb); ret = io_req_task_work_add(req, true); - if (unlikely(ret)) - io_req_task_work_add_fallback(req, io_put_req_deferred_cb); + if (unlikely(ret)) { + struct task_struct *tsk; + + tsk = io_wq_get_task(req->ctx->io_wq); + task_work_add(tsk, &req->task_work, TWA_NONE); + wake_up_process(tsk); + } }

static inline void io_put_req_deferred(struct io_kiocb *req, int refs) @@ -3322,8 +3323,15 @@ static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode, /* submit ref gets dropped, acquire a new one */ refcount_inc(&req->refs); ret = io_req_task_work_add(req, true); - if (unlikely(ret)) - io_req_task_work_add_fallback(req, io_req_task_cancel); + if (unlikely(ret)) { + struct task_struct *tsk; + + /* queue just for cancelation */ + init_task_work(&req->task_work, io_req_task_cancel); + tsk = io_wq_get_task(req->ctx->io_wq); + task_work_add(tsk, &req->task_work, TWA_NONE); + wake_up_process(tsk); + } return 1; }

@@ -4939,8 +4947,12 @@ static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll, */ ret = io_req_task_work_add(req, twa_signal_ok); if (unlikely(ret)) { + struct task_struct *tsk; + WRITE_ONCE(poll->canceled, true); - io_req_task_work_add_fallback(req, func); + tsk = io_wq_get_task(req->ctx->io_wq); + task_work_add(tsk, &req->task_work, TWA_NONE); + wake_up_process(tsk); } return 1; }

From: Jens Axboe axboe@kernel.dk

stable inclusion from stable-v5.10.162 commit c1fe7bd3e1aa85865396b464b31f28b094a4353c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit 6c6ec2b0a3e0381d886d531bd1471dfdb1509237 ]

io_uring always punts opens to async context, since there's no control over whether the lookup blocks or not. Add LOOKUP_CACHED to support just doing the fast RCU based lookups, which we know will not block. If we can do a cached path resolution of the filename, then we don't have to always punt lookups for a worker.

During path resolution, we always do LOOKUP_RCU first. If that fails and we terminate LOOKUP_RCU, then fail a LOOKUP_CACHED attempt as well.

Cc: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

Conflict: fs/namei.c

Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/namei.c | 9 +++++++++ include/linux/namei.h | 1 + 2 files changed, 10 insertions(+)

diff --git a/fs/namei.c b/fs/namei.c index 07c00ade4c1a..98e24fdb22c1 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -691,6 +691,8 @@ static bool try_to_unlazy(struct nameidata *nd) BUG_ON(!(nd->flags & LOOKUP_RCU));

nd->flags &= ~LOOKUP_RCU; + if (nd->flags & LOOKUP_CACHED) + goto out1; if (unlikely(!legitimize_links(nd))) goto out1; if (unlikely(!legitimize_path(nd, &nd->path, nd->seq))) @@ -727,6 +729,8 @@ static int unlazy_child(struct nameidata *nd, struct dentry *dentry, unsigned se BUG_ON(!(nd->flags & LOOKUP_RCU));

nd->flags &= ~LOOKUP_RCU; + if (nd->flags & LOOKUP_CACHED) + goto out2; if (unlikely(!legitimize_links(nd))) goto out2; if (unlikely(!legitimize_mnt(nd->path.mnt, nd->m_seq))) @@ -798,6 +802,7 @@ static int complete_walk(struct nameidata *nd) if (!(nd->state & ND_ROOT_PRESET)) if (!(nd->flags & LOOKUP_IS_SCOPED)) nd->root.mnt = NULL; + nd->flags &= ~LOOKUP_CACHED; if (!try_to_unlazy(nd)) return -ECHILD; } @@ -2210,6 +2215,10 @@ static const char *path_init(struct nameidata *nd, unsigned flags) int error; const char *s = nd->name->name;

+ /* LOOKUP_CACHED requires RCU, ask caller to retry */ + if ((flags & (LOOKUP_RCU | LOOKUP_CACHED)) == LOOKUP_CACHED) + return ERR_PTR(-EAGAIN); + if (!*s) flags &= ~LOOKUP_RCU; if (flags & LOOKUP_RCU) diff --git a/include/linux/namei.h b/include/linux/namei.h index ca94eb5d2b16..be9a2b349ca7 100644 --- a/include/linux/namei.h +++ b/include/linux/namei.h @@ -43,6 +43,7 @@ enum {LAST_NORM, LAST_ROOT, LAST_DOT, LAST_DOTDOT}; #define LOOKUP_NO_XDEV 0x040000 /* No mountpoint crossing. */ #define LOOKUP_BENEATH 0x080000 /* No escaping from starting point. */ #define LOOKUP_IN_ROOT 0x100000 /* Treat dirfd as fs root. */ +#define LOOKUP_CACHED 0x200000 /* Only do cached lookup */ /* LOOKUP_* flags which do scope-related checks based on the dirfd. */ #define LOOKUP_IS_SCOPED (LOOKUP_BENEATH | LOOKUP_IN_ROOT)

From: Al Viro viro@zeniv.linux.org.uk

stable inclusion from stable-v5.10.162 commit 0cf0ce8fb5b10d669072345ea855de112d0e0a43 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit 7d01ef7585c07afaf487759a48486228cd065726 ]

Initialize them in set_nameidata() and make sure that terminate_walk() clears them once the pointers become potentially invalid (i.e. we leave RCU mode or drop them in non-RCU one). Currently we have "path_init() always initializes them and nobody accesses them outside of path_init()/terminate_walk() segments", which is asking for trouble.

With that change we would have nd->path.{mnt,dentry} 1) always valid - NULL or pointing to currently allocated objects. 2) non-NULL while we are successfully walking 3) NULL when we are not walking at all 4) contributing to refcounts whenever non-NULL outside of RCU mode.

Fixes: 6c6ec2b0a3e0 ("fs: add support for LOOKUP_CACHED") Reported-by: syzbot+c88a7030da47945a3cc3@syzkaller.appspotmail.com Tested-by: Christian Brauner christian.brauner@ubuntu.com Signed-off-by: Al Viro viro@zeniv.linux.org.uk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

Conflict： fs/namei.c

Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/namei.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/fs/namei.c b/fs/namei.c index 98b5c4609f25..ce847021d304 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -533,6 +533,8 @@ static void set_nameidata(struct nameidata *p, int dfd, struct filename *name) p->stack = p->internal; p->dfd = dfd; p->name = name; + p->path.mnt = NULL; + p->path.dentry = NULL; p->total_link_count = old ? old->total_link_count : 0; p->saved = old; p->state = 0; @@ -607,6 +609,8 @@ static void terminate_walk(struct nameidata *nd) rcu_read_unlock(); } nd->depth = 0; + nd->path.mnt = NULL; + nd->path.dentry = NULL; }

/* path_put is needed afterwards regardless of success or failure */ @@ -2250,8 +2254,6 @@ static const char *path_init(struct nameidata *nd, unsigned flags) }

nd->root.mnt = NULL; - nd->path.mnt = NULL; - nd->path.dentry = NULL;

/* Absolute pathname -- fetch the root (LOOKUP_IN_ROOT uses nd->dfd). */ if (*s == '/' && !(flags & LOOKUP_IN_ROOT)) {

From: Jens Axboe axboe@kernel.dk

stable inclusion from stable-v5.10.162 commit 069ac28d92432dd7cdac0a2c141a1b3b8d4330d5 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit b713c195d59332277a31a59c91f755e53b5b302b ]

No functional changes in this patch, needed to provide io_uring support for shutdown(2).

Cc: netdev@vger.kernel.org Cc: David S. Miller davem@davemloft.net Acked-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- include/linux/socket.h | 1 + net/socket.c | 15 ++++++++++++--- 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/include/linux/socket.h b/include/linux/socket.h index 9aa530d497da..42222a84167f 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -436,5 +436,6 @@ extern int __sys_getpeername(int fd, struct sockaddr __user *usockaddr, int __user *usockaddr_len); extern int __sys_socketpair(int family, int type, int protocol, int __user *usockvec); +extern int __sys_shutdown_sock(struct socket *sock, int how); extern int __sys_shutdown(int fd, int how); #endif /* _LINUX_SOCKET_H */ diff --git a/net/socket.c b/net/socket.c index 78fdcbe5eaa5..b4d0f9957ffc 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2183,6 +2183,17 @@ SYSCALL_DEFINE5(getsockopt, int, fd, int, level, int, optname, * Shutdown a socket. */

+int __sys_shutdown_sock(struct socket *sock, int how) +{ + int err; + + err = security_socket_shutdown(sock, how); + if (!err) + err = sock->ops->shutdown(sock, how); + + return err; +} + int __sys_shutdown(int fd, int how) { int err, fput_needed; @@ -2190,9 +2201,7 @@ int __sys_shutdown(int fd, int how)

sock = sockfd_lookup_light(fd, &err, &fput_needed); if (sock != NULL) { - err = security_socket_shutdown(sock, how); - if (!err) - err = sock->ops->shutdown(sock, how); + err = __sys_shutdown_sock(sock, how); fput_light(sock->file, fput_needed); } return err;

From: Jens Axboe axboe@kernel.dk

stable inclusion from stable-v5.10.162 commit 214f80e25176eb4d756bc9fe528ef7bf23d2f9a1 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit e886663cfd029b64a1d8da7efae7014526d884e9 ]

Pass in the struct filename pointers instead of the user string, and update the three callers to do the same.

This behaves like do_unlinkat(), which also takes a filename struct and puts it when it is done. Converting callers is then trivial.

Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/internal.h | 2 ++ fs/namei.c | 40 ++++++++++++++++++++++------------------ 2 files changed, 24 insertions(+), 18 deletions(-)

diff --git a/fs/internal.h b/fs/internal.h index 0d4f7e4e2f3a..c42ef7307345 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -77,6 +77,8 @@ extern int vfs_path_lookup(struct dentry *, struct vfsmount *, long do_rmdir(int dfd, struct filename *name); long do_unlinkat(int dfd, struct filename *name); int may_linkat(struct path *link); +int do_renameat2(int olddfd, struct filename *oldname, int newdfd, + struct filename *newname, unsigned int flags);

/* * namespace.c diff --git a/fs/namei.c b/fs/namei.c index ce847021d304..efed178cbf59 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -4365,8 +4365,8 @@ int vfs_rename(struct inode *old_dir, struct dentry *old_dentry, } EXPORT_SYMBOL(vfs_rename);

-static int do_renameat2(int olddfd, const char __user *oldname, int newdfd, - const char __user *newname, unsigned int flags) +int do_renameat2(int olddfd, struct filename *from, int newdfd, + struct filename *to, unsigned int flags) { struct dentry *old_dentry, *new_dentry; struct dentry *trap; @@ -4374,32 +4374,30 @@ static int do_renameat2(int olddfd, const char __user *oldname, int newdfd, struct qstr old_last, new_last; int old_type, new_type; struct inode *delegated_inode = NULL; - struct filename *from; - struct filename *to; unsigned int lookup_flags = 0, target_flags = LOOKUP_RENAME_TARGET; bool should_retry = false; - int error; + int error = -EINVAL;

if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT)) - return -EINVAL; + goto put_both;

if ((flags & (RENAME_NOREPLACE | RENAME_WHITEOUT)) && (flags & RENAME_EXCHANGE)) - return -EINVAL; + goto put_both;

if (flags & RENAME_EXCHANGE) target_flags = 0;

retry: - from = filename_parentat(olddfd, getname(oldname), lookup_flags, - &old_path, &old_last, &old_type); + from = filename_parentat(olddfd, from, lookup_flags, &old_path, + &old_last, &old_type); if (IS_ERR(from)) { error = PTR_ERR(from); - goto exit; + goto put_new; }

- to = filename_parentat(newdfd, getname(newname), lookup_flags, - &new_path, &new_last, &new_type); + to = filename_parentat(newdfd, to, lookup_flags, &new_path, &new_last, + &new_type); if (IS_ERR(to)) { error = PTR_ERR(to); goto exit1; @@ -4492,34 +4490,40 @@ static int do_renameat2(int olddfd, const char __user *oldname, int newdfd, if (retry_estale(error, lookup_flags)) should_retry = true; path_put(&new_path); - putname(to); exit1: path_put(&old_path); - putname(from); if (should_retry) { should_retry = false; lookup_flags |= LOOKUP_REVAL; goto retry; } -exit: +put_both: + if (!IS_ERR(from)) + putname(from); +put_new: + if (!IS_ERR(to)) + putname(to); return error; }

SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname, unsigned int, flags) { - return do_renameat2(olddfd, oldname, newdfd, newname, flags); + return do_renameat2(olddfd, getname(oldname), newdfd, getname(newname), + flags); }

SYSCALL_DEFINE4(renameat, int, olddfd, const char __user *, oldname, int, newdfd, const char __user *, newname) { - return do_renameat2(olddfd, oldname, newdfd, newname, 0); + return do_renameat2(olddfd, getname(oldname), newdfd, getname(newname), + 0); }

SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newname) { - return do_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0); + return do_renameat2(AT_FDCWD, getname(oldname), AT_FDCWD, + getname(newname), 0); }

int readlink_copy(char __user *buffer, int buflen, const char *link)

From: Hao Xu haoxu@linux.alibaba.com

stable inclusion from stable-v5.10.158 commit a2efc465245e535fefcad8c4ed5967254344257d category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

commit 8bad28d8a305b0e5ae444c8c3051e8744f5a4296 upstream.

Abaci reported the below issue: [ 141.400455] hrtimer: interrupt took 205853 ns [ 189.869316] process 'usr/local/ilogtail/ilogtail_0.16.26' started with executable stack [ 250.188042] [ 250.188327] ============================================ [ 250.189015] WARNING: possible recursive locking detected [ 250.189732] 5.11.0-rc4 #1 Not tainted [ 250.190267] -------------------------------------------- [ 250.190917] a.out/7363 is trying to acquire lock: [ 250.191506] ffff888114dbcbe8 (&ctx->uring_lock){+.+.}-{3:3}, at: __io_req_task_submit+0x29/0xa0 [ 250.192599] [ 250.192599] but task is already holding lock: [ 250.193309] ffff888114dbfbe8 (&ctx->uring_lock){+.+.}-{3:3}, at: __x64_sys_io_uring_register+0xad/0x210 [ 250.194426] [ 250.194426] other info that might help us debug this: [ 250.195238] Possible unsafe locking scenario: [ 250.195238] [ 250.196019] CPU0 [ 250.196411] ---- [ 250.196803] lock(&ctx->uring_lock); [ 250.197420] lock(&ctx->uring_lock); [ 250.197966] [ 250.197966] *** DEADLOCK *** [ 250.197966] [ 250.198837] May be due to missing lock nesting notation [ 250.198837] [ 250.199780] 1 lock held by a.out/7363: [ 250.200373] #0: ffff888114dbfbe8 (&ctx->uring_lock){+.+.}-{3:3}, at: __x64_sys_io_uring_register+0xad/0x210 [ 250.201645] [ 250.201645] stack backtrace: [ 250.202298] CPU: 0 PID: 7363 Comm: a.out Not tainted 5.11.0-rc4 #1 [ 250.203144] Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011 [ 250.203887] Call Trace: [ 250.204302] dump_stack+0xac/0xe3 [ 250.204804] __lock_acquire+0xab6/0x13a0 [ 250.205392] lock_acquire+0x2c3/0x390 [ 250.205928] ? __io_req_task_submit+0x29/0xa0 [ 250.206541] __mutex_lock+0xae/0x9f0 [ 250.207071] ? __io_req_task_submit+0x29/0xa0 [ 250.207745] ? 0xffffffffa0006083 [ 250.208248] ? __io_req_task_submit+0x29/0xa0 [ 250.208845] ? __io_req_task_submit+0x29/0xa0 [ 250.209452] ? __io_req_task_submit+0x5/0xa0 [ 250.210083] __io_req_task_submit+0x29/0xa0 [ 250.210687] io_async_task_func+0x23d/0x4c0 [ 250.211278] task_work_run+0x89/0xd0 [ 250.211884] io_run_task_work_sig+0x50/0xc0 [ 250.212464] io_sqe_files_unregister+0xb2/0x1f0 [ 250.213109] __io_uring_register+0x115a/0x1750 [ 250.213718] ? __x64_sys_io_uring_register+0xad/0x210 [ 250.214395] ? __fget_files+0x15a/0x260 [ 250.214956] __x64_sys_io_uring_register+0xbe/0x210 [ 250.215620] ? trace_hardirqs_on+0x46/0x110 [ 250.216205] do_syscall_64+0x2d/0x40 [ 250.216731] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 250.217455] RIP: 0033:0x7f0fa17e5239 [ 250.218034] Code: 01 00 48 81 c4 80 00 00 00 e9 f1 fe ff ff 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 3d 01 f0 ff ff 73 01 c3 48 8b 0d 27 ec 2c 00 f7 d8 64 89 01 48 [ 250.220343] RSP: 002b:00007f0fa1eeac48 EFLAGS: 00000246 ORIG_RAX: 00000000000001ab [ 250.221360] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f0fa17e5239 [ 250.222272] RDX: 0000000000000000 RSI: 0000000000000003 RDI: 0000000000000008 [ 250.223185] RBP: 00007f0fa1eeae20 R08: 0000000000000000 R09: 0000000000000000 [ 250.224091] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 [ 250.224999] R13: 0000000000021000 R14: 0000000000000000 R15: 00007f0fa1eeb700

This is caused by calling io_run_task_work_sig() to do work under uring_lock while the caller io_sqe_files_unregister() already held uring_lock. To fix this issue, briefly drop uring_lock when calling io_run_task_work_sig(), and there are two things to concern:

- hold uring_lock in io_ring_ctx_free() around io_sqe_files_unregister() this is for consistency of lock/unlock. - add new fixed rsrc ref node before dropping uring_lock it's not safe to do io_uring_enter-->percpu_ref_get() with a dying one. - check if rsrc_data->refs is dying to avoid parallel io_sqe_files_unregister

Reported-by: Abaci abaci@linux.alibaba.com Fixes: 1ffc54220c44 ("io_uring: fix io_sqe_files_unregister() hangs") Suggested-by: Pavel Begunkov asml.silence@gmail.com Signed-off-by: Hao Xu haoxu@linux.alibaba.com [axboe: fixes from Pavel folded in] Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Samiullah Khawaja skhawaja@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/io_uring.c | 82 ++++++++++++++++++++++++++++++++++++++------------- 1 file changed, 61 insertions(+), 21 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c index 85c2321d833b..add03c27aa13 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -217,6 +217,7 @@ struct fixed_file_data { struct completion done; struct list_head ref_list; spinlock_t lock; + bool quiesce; };

struct io_buffer { @@ -7105,41 +7106,79 @@ static void io_sqe_files_set_node(struct fixed_file_data *file_data, percpu_ref_get(&file_data->refs); }

-static int io_sqe_files_unregister(struct io_ring_ctx *ctx) -{ - struct fixed_file_data *data = ctx->file_data; - struct fixed_file_ref_node *backup_node, *ref_node = NULL; - unsigned nr_tables, i; - int ret;

- if (!data) - return -ENXIO; - backup_node = alloc_fixed_file_ref_node(ctx); - if (!backup_node) - return -ENOMEM; +static void io_sqe_files_kill_node(struct fixed_file_data *data) +{ + struct fixed_file_ref_node *ref_node = NULL;

spin_lock_bh(&data->lock); ref_node = data->node; spin_unlock_bh(&data->lock); if (ref_node) percpu_ref_kill(&ref_node->refs); +} + +static int io_file_ref_quiesce(struct fixed_file_data *data, + struct io_ring_ctx *ctx) +{ + int ret; + struct fixed_file_ref_node *backup_node;

- percpu_ref_kill(&data->refs); + if (data->quiesce) + return -ENXIO;

- /* wait for all refs nodes to complete */ - flush_delayed_work(&ctx->file_put_work); + data->quiesce = true; do { + backup_node = alloc_fixed_file_ref_node(ctx); + if (!backup_node) + break; + + io_sqe_files_kill_node(data); + percpu_ref_kill(&data->refs); + flush_delayed_work(&ctx->file_put_work); + ret = wait_for_completion_interruptible(&data->done); if (!ret) break; + + percpu_ref_resurrect(&data->refs); + io_sqe_files_set_node(data, backup_node); + backup_node = NULL; + reinit_completion(&data->done); + mutex_unlock(&ctx->uring_lock); ret = io_run_task_work_sig(); - if (ret < 0) { - percpu_ref_resurrect(&data->refs); - reinit_completion(&data->done); - io_sqe_files_set_node(data, backup_node); - return ret; - } + mutex_lock(&ctx->uring_lock); + + if (ret < 0) + break; + backup_node = alloc_fixed_file_ref_node(ctx); + ret = -ENOMEM; + if (!backup_node) + break; } while (1); + data->quiesce = false; + + if (backup_node) + destroy_fixed_file_ref_node(backup_node); + return ret; +} + +static int io_sqe_files_unregister(struct io_ring_ctx *ctx) +{ + struct fixed_file_data *data = ctx->file_data; + unsigned nr_tables, i; + int ret; + + /* + * percpu_ref_is_dying() is to stop parallel files unregister + * Since we possibly drop uring lock later in this function to + * run task work. + */ + if (!data || percpu_ref_is_dying(&data->refs)) + return -ENXIO; + ret = io_file_ref_quiesce(data, ctx); + if (ret) + return ret;

__io_sqe_files_unregister(ctx); nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE); @@ -7150,7 +7189,6 @@ static int io_sqe_files_unregister(struct io_ring_ctx *ctx) kfree(data); ctx->file_data = NULL; ctx->nr_user_files = 0; - destroy_fixed_file_ref_node(backup_node); return 0; }

@@ -8446,7 +8484,9 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx) css_put(ctx->sqo_blkcg_css); #endif

+ mutex_lock(&ctx->uring_lock); io_sqe_files_unregister(ctx); + mutex_unlock(&ctx->uring_lock); io_eventfd_unregister(ctx); io_destroy_buffers(ctx);

From: Pavel Begunkov asml.silence@gmail.com

stable inclusion from stable-v5.10.150 commit 67cbc8865a66533fa08c1c13fe9acbaaae63c403 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ upstream commit 42b6419d0aba47c5d8644cdc0b68502254671de5 ]

->mm_account should be released only after we free all registered buffers, otherwise __io_sqe_buffers_unregister() will see a NULL ->mm_account and skip locked_vm accounting.

Cc: Stable@vger.kernel.org Signed-off-by: Pavel Begunkov asml.silence@gmail.com Link: https://lore.kernel.org/r/6d798f65ed4ab8db3664c4d3397d4af16ca98846.166484993... Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/io_uring.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c index cfcdea67a0e3..1d8173741310 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -8475,8 +8475,6 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx) if (ctx->sqo_task) { put_task_struct(ctx->sqo_task); ctx->sqo_task = NULL; - mmdrop(ctx->mm_account); - ctx->mm_account = NULL; }

#ifdef CONFIG_BLK_CGROUP @@ -8497,6 +8495,11 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx) } #endif

+ if (ctx->mm_account) { + mmdrop(ctx->mm_account); + ctx->mm_account = NULL; + } + io_mem_free(ctx->rings); io_mem_free(ctx->sq_sqes);

From: Arnaldo Carvalho de Melo acme@redhat.com

mainline inclusion from mainline-v5.15-rc1 commit bb91de44693b1c10fe2f9e668506b01e88efed0e category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?h...

--------------------------------

To pick the changes in:

Fixes: d32f89da7fa8ccc8 ("net: add accept helper not installing fd") Fixes: bc49d8169aa72295 ("mctp: Add MCTP base")

This automagically adds support for the AF_MCTP protocol domain:

$ tools/perf/trace/beauty/socket.sh > before $ cp include/linux/socket.h tools/perf/trace/beauty/include/linux/socket.h $ tools/perf/trace/beauty/socket.sh > after $ diff -u before after --- before 2021-09-06 11:57:14.972747200 -0300 +++ after 2021-09-06 11:57:30.541920222 -0300 @@ -44,4 +44,5 @@ [42] = "QIPCRTR", [43] = "SMC", [44] = "XDP", + [45] = "MCTP", }; $

This will allow 'perf trace' to translate 45 into "MCTP" as is done with the other domains:

# perf trace -e socket* 0.000 chronyd/1029 socket(family: INET, type: DGRAM|CLOEXEC|NONBLOCK, protocol: IP) = 4 ^C#

This addresses this perf build warning:

Warning: Kernel ABI header at 'tools/perf/trace/beauty/include/linux/socket.h' differs from latest version at 'include/linux/socket.h' diff -u tools/perf/trace/beauty/include/linux/socket.h include/linux/socket.h

Cc: David S. Miller davem@davemloft.net Cc: Jens Axboe axboe@kernel.dk Cc: Jeremy Kerr jk@codeconstruct.com.au Cc: Pavel Begunkov asml.silence@gmail.com Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com

Conflict: tools/perf/trace/beauty/include/linux/socket.h

Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- tools/perf/trace/beauty/include/linux/socket.h | 3 +++ 1 file changed, 3 insertions(+)

diff --git a/tools/perf/trace/beauty/include/linux/socket.h b/tools/perf/trace/beauty/include/linux/socket.h index 42222a84167f..c3b35d18bcd3 100644 --- a/tools/perf/trace/beauty/include/linux/socket.h +++ b/tools/perf/trace/beauty/include/linux/socket.h @@ -421,6 +421,9 @@ extern int __sys_accept4_file(struct file *file, unsigned file_flags, struct sockaddr __user *upeer_sockaddr, int __user *upeer_addrlen, int flags, unsigned long nofile); +extern struct file *do_accept(struct file *file, unsigned file_flags, + struct sockaddr __user *upeer_sockaddr, + int __user *upeer_addrlen, int flags); extern int __sys_accept4(int fd, struct sockaddr __user *upeer_sockaddr, int __user *upeer_addrlen, int flags); extern int __sys_socket(int family, int type, int protocol);

From: Jens Axboe axboe@kernel.dk

stable inclusion from stable-v5.10.162 commit 4b1dcf8ec9b2f11b57f1ff5dcaa1f8575c7dacb5 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit c8d5ed67936fddbe2ae845fc80397718006322d7 ]

The generic entry code has support for TIF_NOTIFY_SIGNAL already. Just provide the TIF bit.

[ tglx: Adopted to other TIF changes in x86 ]

Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Thomas Gleixner tglx@linutronix.de Link: https://lore.kernel.org/r/20201026203230.386348-4-axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- arch/x86/include/asm/thread_info.h | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/arch/x86/include/asm/thread_info.h b/arch/x86/include/asm/thread_info.h index a225c6e2ca6d..2b3c980698a3 100644 --- a/arch/x86/include/asm/thread_info.h +++ b/arch/x86/include/asm/thread_info.h @@ -99,6 +99,7 @@ struct thread_info { #define TIF_NOTSC 16 /* TSC is not accessible in userland */ #define TIF_IA32 17 /* IA32 compatibility process */ #define TIF_SLD 18 /* Restore split lock detection on context switch */ +#define TIF_NOTIFY_SIGNAL 19 /* signal notifications exist */ #define TIF_MEMDIE 20 /* is terminating due to OOM killer */ #define TIF_POLLING_NRFLAG 21 /* idle is polling for TIF_NEED_RESCHED */ #define TIF_IO_BITMAP 22 /* uses I/O bitmap */ @@ -127,6 +128,7 @@ struct thread_info { #define _TIF_NOCPUID (1 << TIF_NOCPUID) #define _TIF_NOTSC (1 << TIF_NOTSC) #define _TIF_IA32 (1 << TIF_IA32) +#define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL) #define _TIF_SLD (1 << TIF_SLD) #define _TIF_POLLING_NRFLAG (1 << TIF_POLLING_NRFLAG) #define _TIF_IO_BITMAP (1 << TIF_IO_BITMAP)

From: Jens Axboe axboe@kernel.dk

stable inclusion from stable-v5.10.162 commit 78a53ff02656da3c1e6a3e11e30ab23cf4bcb0f7 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit 24a31b81e38309b1604f24520110aae1f83f3cbf ]

Wire up TIF_NOTIFY_SIGNAL handling for riscv.

Cc: linux-riscv@lists.infradead.org Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- arch/riscv/include/asm/thread_info.h | 5 ++++- arch/riscv/kernel/signal.c | 2 +- 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/arch/riscv/include/asm/thread_info.h b/arch/riscv/include/asm/thread_info.h index d79ae9d98999..c55e0a1f07a0 100644 --- a/arch/riscv/include/asm/thread_info.h +++ b/arch/riscv/include/asm/thread_info.h @@ -80,6 +80,7 @@ struct thread_info { #define TIF_SYSCALL_TRACEPOINT 6 /* syscall tracepoint instrumentation */ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing */ #define TIF_SECCOMP 8 /* syscall secure computing */ +#define TIF_NOTIFY_SIGNAL 9 /* signal notifications exist */

#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) @@ -88,9 +89,11 @@ struct thread_info { #define _TIF_SYSCALL_TRACEPOINT (1 << TIF_SYSCALL_TRACEPOINT) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) +#define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL)

#define _TIF_WORK_MASK \ - (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED) + (_TIF_NOTIFY_RESUME | _TIF_SIGPENDING | _TIF_NEED_RESCHED | \ + _TIF_NOTIFY_SIGNAL)

#define _TIF_SYSCALL_WORK \ (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_TRACEPOINT | _TIF_SYSCALL_AUDIT | \ diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c index 529c123cf0a4..50a8225c58bc 100644 --- a/arch/riscv/kernel/signal.c +++ b/arch/riscv/kernel/signal.c @@ -312,7 +312,7 @@ asmlinkage __visible void do_notify_resume(struct pt_regs *regs, unsigned long thread_info_flags) { /* Handle pending signal delivery */ - if (thread_info_flags & _TIF_SIGPENDING) + if (thread_info_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) do_signal(regs);

if (thread_info_flags & _TIF_NOTIFY_RESUME)

From: Jens Axboe axboe@kernel.dk

stable inclusion from stable-v5.10.162 commit 1bee9dbbcabbb77617fb257f964628b50ba2529c category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit 32d59773da38cd83e497a70eb9754d4bbae3aeae ]

Wire up TIF_NOTIFY_SIGNAL handling for arm.

Cc: linux-arm-kernel@lists.infradead.org Acked-by: Russell King rmk+kernel@armlinux.org.uk Signed-off-by: Jens Axboe axboe@kernel.dk

Conflicts: arch/arm/include/asm/thread_info.h

Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: tanghui tanghui20@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- arch/arm/include/asm/thread_info.h | 7 ++++++- arch/arm/kernel/entry-common.S | 6 +++--- arch/arm/kernel/entry-v7m.S | 2 +- arch/arm/kernel/signal.c | 2 +- 4 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index 9f7ca79cc76a..070375d96e24 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -137,6 +137,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp *, * thread information flags: * TIF_USEDFPU - FPU was used by this task this quantum (SMP) * TIF_POLLING_NRFLAG - true if poll_idle() is polling TIF_NEED_RESCHED + * + * Any bit in the range of 0..15 will cause do_work_pending() to be invoked. */ #define TIF_SIGPENDING 0 /* signal pending */ #define TIF_NEED_RESCHED 1 /* rescheduling necessary */ @@ -147,6 +149,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *, #define TIF_SYSCALL_TRACEPOINT 6 /* syscall tracepoint instrumentation */ #define TIF_SECCOMP 7 /* seccomp syscall filtering active */ #define TIF_PATCH_PENDING 8 /* pending live patching update */ +#define TIF_NOTIFY_SIGNAL 9 /* signal notifications exist */

#define TIF_USING_IWMMXT 17 #define TIF_MEMDIE 18 /* is terminating due to OOM killer */ @@ -162,6 +165,7 @@ extern int vfp_restore_user_hwstate(struct user_vfp *, #define _TIF_SECCOMP (1 << TIF_SECCOMP) #define _TIF_USING_IWMMXT (1 << TIF_USING_IWMMXT) #define _TIF_PATCH_PENDING (1 << TIF_PATCH_PENDING) +#define _TIF_NOTIFY_SIGNAL (1 << TIF_NOTIFY_SIGNAL)

/* Checks for any syscall work in entry-common.S */ #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ @@ -171,7 +175,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp *, * Change these and you break ASM code in entry-common.S */ #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ - _TIF_NOTIFY_RESUME | _TIF_UPROBE) + _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ + _TIF_NOTIFY_SIGNAL)

#endif /* __KERNEL__ */ #endif /* __ASM_ARM_THREAD_INFO_H */ diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S index 7a2e63dfb4d9..b22813760210 100644 --- a/arch/arm/kernel/entry-common.S +++ b/arch/arm/kernel/entry-common.S @@ -54,7 +54,7 @@ __ret_fast_syscall: cmp r2, r1 blne addr_limit_check_failed ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing - tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK + movs r1, r1, lsl #16 bne fast_work_pending

@@ -92,7 +92,7 @@ __ret_fast_syscall: cmp r2, r1 blne addr_limit_check_failed ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing - tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK + movs r1, r1, lsl #16 beq no_work_pending UNWIND(.fnend ) ENDPROC(ret_fast_syscall) @@ -134,7 +134,7 @@ ENTRY(ret_to_user_from_irq) cmp r2, r1 blne addr_limit_check_failed ldr r1, [tsk, #TI_FLAGS] - tst r1, #_TIF_WORK_MASK + movs r1, r1, lsl #16 bne slow_work_pending no_work_pending: asm_trace_hardirqs_on save = 0 diff --git a/arch/arm/kernel/entry-v7m.S b/arch/arm/kernel/entry-v7m.S index de1f20624be1..d0e898608d30 100644 --- a/arch/arm/kernel/entry-v7m.S +++ b/arch/arm/kernel/entry-v7m.S @@ -59,7 +59,7 @@ __irq_entry:

get_thread_info tsk ldr r2, [tsk, #TI_FLAGS] - tst r2, #_TIF_WORK_MASK + movs r2, r2, lsl #16 beq 2f @ no work pending mov r0, #V7M_SCB_ICSR_PENDSVSET str r0, [r1, V7M_SCB_ICSR] @ raise PendSV diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 2f81d3af5f9a..a3a38d0a4c85 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -655,7 +655,7 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) if (unlikely(!user_mode(regs))) return 0; local_irq_enable(); - if (thread_flags & _TIF_SIGPENDING) { + if (thread_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) { int restart = do_signal(regs, syscall); if (unlikely(restart)) { /*

From: Jens Axboe axboe@kernel.dk

stable inclusion from stable-v5.10.162 commit 3c295bd2ddaecf3509458c86bf7ba610042f3609 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit 12db8b690010ccfadf9d0b49a1e1798e47dbbe1a ]

Add TIF_NOTIFY_SIGNAL handling in the generic entry code, which if set, will return true if signal_pending() is used in a wait loop. That causes an exit of the loop so that notify_signal tracehooks can be run. If the wait loop is currently inside a system call, the system call is restarted once task_work has been processed.

In preparation for only having arch_do_signal() handle syscall restarts if _TIF_SIGPENDING isn't set, rename it to arch_do_signal_or_restart(). Pass in a boolean that tells the architecture specific signal handler if it should attempt to get a signal, or just process a potential syscall restart.

For !CONFIG_GENERIC_ENTRY archs, add the TIF_NOTIFY_SIGNAL handling to get_signal(). This is done to minimize the needed architecture changes to support this feature.

Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Thomas Gleixner tglx@linutronix.de Reviewed-by: Oleg Nesterov oleg@redhat.com Link: https://lore.kernel.org/r/20201026203230.386348-3-axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

Conflict: include/linux/tracehook.h

Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: tanghui tanghui20@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- arch/x86/kernel/signal.c | 4 ++-- include/linux/entry-common.h | 11 ++++++++--- include/linux/entry-kvm.h | 4 ++-- include/linux/sched/signal.h | 11 ++++++++++- include/linux/tracehook.h | 27 +++++++++++++++++++++++++++ kernel/entry/common.c | 14 +++++++++++--- kernel/entry/kvm.c | 3 +++ kernel/signal.c | 14 ++++++++++++++ 8 files changed, 77 insertions(+), 11 deletions(-)

diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index bc8a42d0adb8..8c991c547305 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -860,11 +860,11 @@ static inline unsigned long get_nr_restart_syscall(const struct pt_regs *regs) * want to handle. Thus you cannot kill init even with a SIGKILL even by * mistake. */ -void arch_do_signal(struct pt_regs *regs) +void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal) { struct ksignal ksig;

- if (get_signal(&ksig)) { + if (has_signal && get_signal(&ksig)) { /* Whee! Actually deliver the signal. */ handle_signal(&ksig, regs); return; diff --git a/include/linux/entry-common.h b/include/linux/entry-common.h index d8e1c798dc9d..cce104df51cb 100644 --- a/include/linux/entry-common.h +++ b/include/linux/entry-common.h @@ -38,6 +38,10 @@ # define _TIF_UPROBE (0) #endif

+#ifndef _TIF_NOTIFY_SIGNAL +# define _TIF_NOTIFY_SIGNAL (0) +#endif + /* * TIF flags handled in syscall_enter_from_user_mode() */ @@ -70,7 +74,7 @@

#define EXIT_TO_USER_MODE_WORK \ (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ - _TIF_NEED_RESCHED | _TIF_PATCH_PENDING | \ + _TIF_NEED_RESCHED | _TIF_PATCH_PENDING | _TIF_NOTIFY_SIGNAL | \ ARCH_EXIT_TO_USER_MODE_WORK)

/** @@ -260,12 +264,13 @@ static __always_inline void arch_exit_to_user_mode(void) { } #endif

/** - * arch_do_signal - Architecture specific signal delivery function + * arch_do_signal_or_restart - Architecture specific signal delivery function * @regs: Pointer to currents pt_regs + * @has_signal: actual signal to handle * * Invoked from exit_to_user_mode_loop(). */ -void arch_do_signal(struct pt_regs *regs); +void arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal);

/** * arch_syscall_exit_tracehook - Wrapper around tracehook_report_syscall_exit() diff --git a/include/linux/entry-kvm.h b/include/linux/entry-kvm.h index f49472ebd8a4..859fdfd7d46c 100644 --- a/include/linux/entry-kvm.h +++ b/include/linux/entry-kvm.h @@ -15,8 +15,8 @@ # define ARCH_XFER_TO_GUEST_MODE_WORK (0) #endif

-#define XFER_TO_GUEST_MODE_WORK \ - (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ +#define XFER_TO_GUEST_MODE_WORK \ + (_TIF_NEED_RESCHED | _TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL | \ _TIF_NOTIFY_RESUME | ARCH_XFER_TO_GUEST_MODE_WORK)

struct kvm_vcpu; diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h index 00966c66a17c..7a83bd4c82a9 100644 --- a/include/linux/sched/signal.h +++ b/include/linux/sched/signal.h @@ -367,6 +367,15 @@ static inline int task_sigpending(struct task_struct *p)

static inline int signal_pending(struct task_struct *p) { +#if defined(TIF_NOTIFY_SIGNAL) + /* + * TIF_NOTIFY_SIGNAL isn't really a signal, but it requires the same + * behavior in terms of ensuring that we break out of wait loops + * so that notify signal callbacks can be processed. + */ + if (unlikely(test_tsk_thread_flag(p, TIF_NOTIFY_SIGNAL))) + return 1; +#endif return task_sigpending(p); }

@@ -514,7 +523,7 @@ extern int set_user_sigmask(const sigset_t __user *umask, size_t sigsetsize); static inline void restore_saved_sigmask_unless(bool interrupted) { if (interrupted) - WARN_ON(!test_thread_flag(TIF_SIGPENDING)); + WARN_ON(!signal_pending(current)); else restore_saved_sigmask(); } diff --git a/include/linux/tracehook.h b/include/linux/tracehook.h index 5913deb26219..53f5065d7e80 100644 --- a/include/linux/tracehook.h +++ b/include/linux/tracehook.h @@ -202,4 +202,31 @@ static inline void tracehook_notify_resume(struct pt_regs *regs)

}

+/* + * called by exit_to_user_mode_loop() if ti_work & _TIF_NOTIFY_SIGNAL. This + * is currently used by TWA_SIGNAL based task_work, which requires breaking + * wait loops to ensure that task_work is noticed and run. + */ +static inline void tracehook_notify_signal(void) +{ +#if defined(TIF_NOTIFY_SIGNAL) + clear_thread_flag(TIF_NOTIFY_SIGNAL); + smp_mb__after_atomic(); + if (current->task_works) + task_work_run(); +#endif +} + +/* + * Called when we have work to process from exit_to_user_mode_loop() + */ +static inline void set_notify_signal(struct task_struct *task) +{ +#if defined(TIF_NOTIFY_SIGNAL) + if (!test_and_set_tsk_thread_flag(task, TIF_NOTIFY_SIGNAL) && + !wake_up_state(task, TASK_INTERRUPTIBLE)) + kick_process(task); +#endif +} + #endif /* <linux/tracehook.h> */ diff --git a/kernel/entry/common.c b/kernel/entry/common.c index 2228de39bb4f..a028b28daed5 100644 --- a/kernel/entry/common.c +++ b/kernel/entry/common.c @@ -135,7 +135,15 @@ static __always_inline void exit_to_user_mode(void) }

/* Workaround to allow gradual conversion of architecture code */ -void __weak arch_do_signal(struct pt_regs *regs) { } +void __weak arch_do_signal_or_restart(struct pt_regs *regs, bool has_signal) { } + +static void handle_signal_work(struct pt_regs *regs, unsigned long ti_work) +{ + if (ti_work & _TIF_NOTIFY_SIGNAL) + tracehook_notify_signal(); + + arch_do_signal_or_restart(regs, ti_work & _TIF_SIGPENDING); +}

static unsigned long exit_to_user_mode_loop(struct pt_regs *regs, unsigned long ti_work) @@ -157,8 +165,8 @@ static unsigned long exit_to_user_mode_loop(struct pt_regs *regs, if (ti_work & _TIF_PATCH_PENDING) klp_update_patch_state(current);

- if (ti_work & _TIF_SIGPENDING) - arch_do_signal(regs); + if (ti_work & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL)) + handle_signal_work(regs, ti_work);

if (ti_work & _TIF_NOTIFY_RESUME) { tracehook_notify_resume(regs); diff --git a/kernel/entry/kvm.c b/kernel/entry/kvm.c index 2a3139dab109..049fd06b4c3d 100644 --- a/kernel/entry/kvm.c +++ b/kernel/entry/kvm.c @@ -8,6 +8,9 @@ static int xfer_to_guest_mode_work(struct kvm_vcpu *vcpu, unsigned long ti_work) do { int ret;

+ if (ti_work & _TIF_NOTIFY_SIGNAL) + tracehook_notify_signal(); + if (ti_work & _TIF_SIGPENDING) { kvm_handle_signal_exit(vcpu); return -EINTR; diff --git a/kernel/signal.c b/kernel/signal.c index c704b7a40628..c2afe6430e4d 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2526,6 +2526,20 @@ bool get_signal(struct ksignal *ksig) struct signal_struct *signal = current->signal; int signr;

+ /* + * For non-generic architectures, check for TIF_NOTIFY_SIGNAL so + * that the arch handlers don't all have to do it. If we get here + * without TIF_SIGPENDING, just exit after running signal work. + */ +#ifdef TIF_NOTIFY_SIGNAL + if (!IS_ENABLED(CONFIG_GENERIC_ENTRY)) { + if (test_thread_flag(TIF_NOTIFY_SIGNAL)) + tracehook_notify_signal(); + if (!task_sigpending(current)) + return false; + } +#endif + if (unlikely(uprobe_deny_signal())) return false;

From: Jens Axboe axboe@kernel.dk

stable inclusion from stable-v5.10.162 commit d2136fc145be417e851dfe50703fac2af6aabe46 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit 53dec2ea74f2ef360e8455439be96a780baa6097 ]

Assumes current->files->file_lock is already held on invocation. Helps the caller check the file before removing the fd, if it needs to.

Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/file.c | 36 +++++++++++++++++++++++++----------- fs/internal.h | 1 + 2 files changed, 26 insertions(+), 11 deletions(-)

diff --git a/fs/file.c b/fs/file.c index 045a29e55c3d..f1b6faa87e3d 100644 --- a/fs/file.c +++ b/fs/file.c @@ -23,6 +23,8 @@ #include <linux/close_range.h> #include <net/sock.h>

+#include "internal.h" + unsigned int sysctl_nr_open __read_mostly = 1024*1024; unsigned int sysctl_nr_open_min = BITS_PER_LONG; /* our min() is unusable in constant expressions ;-/ */ @@ -829,36 +831,48 @@ int __close_range(unsigned fd, unsigned max_fd, unsigned int flags) }

/* - * variant of close_fd that gets a ref on the file for later fput. - * The caller must ensure that filp_close() called on the file, and then - * an fput(). + * See close_fd_get_file() below, this variant assumes current->files->file_lock + * is held. */ -int close_fd_get_file(unsigned int fd, struct file **res) +int __close_fd_get_file(unsigned int fd, struct file **res) { struct files_struct *files = current->files; struct file *file; struct fdtable *fdt;

- spin_lock(&files->file_lock); fdt = files_fdtable(files); if (fd >= fdt->max_fds) - goto out_unlock; + goto out_err; file = fdt->fd[fd]; if (!file) - goto out_unlock; + goto out_err; rcu_assign_pointer(fdt->fd[fd], NULL); __put_unused_fd(files, fd); - spin_unlock(&files->file_lock); get_file(file); *res = file; return 0; - -out_unlock: - spin_unlock(&files->file_lock); +out_err: *res = NULL; return -ENOENT; }

+/* + * variant of close_fd that gets a ref on the file for later fput. + * The caller must ensure that filp_close() called on the file, and then + * an fput(). + */ +int close_fd_get_file(unsigned int fd, struct file **res) +{ + struct files_struct *files = current->files; + int ret; + + spin_lock(&files->file_lock); + ret = __close_fd_get_file(fd, res); + spin_unlock(&files->file_lock); + + return ret; +} + void do_close_on_exec(struct files_struct *files) { unsigned i; diff --git a/fs/internal.h b/fs/internal.h index c42ef7307345..572ab0f26b67 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -134,6 +134,7 @@ extern struct file *do_file_open_root(const struct path *, const char *, const struct open_flags *); extern struct open_how build_open_how(int flags, umode_t mode); extern int build_open_flags(const struct open_how *how, struct open_flags *op); +extern int __close_fd_get_file(unsigned int fd, struct file **res);

long do_sys_ftruncate(unsigned int fd, loff_t length, int small); int chmod_common(const struct path *path, umode_t mode);

From: "Eric W. Biederman" ebiederm@xmission.com

stable inclusion from stable-v5.10.162 commit 4b4d2c79921a8327e9e853dc93c06b27edb3a859 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

[ Upstream commit 06af8679449d4ed282df13191fc52d5ba28ec536 ]

Olivier Langlois has been struggling with coredumps being incompletely written in processes using io_uring.

Olivier Langlois olivier@trillion01.com writes:

io_uring is a big user of task_work and any event that io_uring made a task waiting for that occurs during the core dump generation will generate a TIF_NOTIFY_SIGNAL.

Here are the detailed steps of the problem:

1. io_uring calls vfs_poll() to install a task to a file wait queue with io_async_wake() as the wakeup function cb from io_arm_poll_handler()
2. wakeup function ends up calling task_work_add() with TWA_SIGNAL
3. task_work_add() sets the TIF_NOTIFY_SIGNAL bit by calling set_notify_signal()

The coredump code deliberately supports being interrupted by SIGKILL, and depends upon prepare_signal to filter out all other signals. Now that signal_pending includes wake ups for TIF_NOTIFY_SIGNAL this hack in dump_emitted by the coredump code no longer works.

Make the coredump code more robust by explicitly testing for all of the wakeup conditions the coredump code supports. This prevents new wakeup conditions from breaking the coredump code, as well as fixing the current issue.

The filesystem code that the coredump code uses already limits itself to only aborting on fatal_signal_pending. So it should not develop surprising wake-up reasons either.

v2: Don't remove the now unnecessary code in prepare_signal.

Cc: stable@vger.kernel.org Fixes: 12db8b690010 ("entry: Add support for TIF_NOTIFY_SIGNAL") Reported-by: Olivier Langlois olivier@trillion01.com Signed-off-by: "Eric W. Biederman" ebiederm@xmission.com Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Acked-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- fs/coredump.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/coredump.c b/fs/coredump.c index eea9dbc1264a..2941cc43a420 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -520,7 +520,7 @@ static bool dump_interrupted(void) * but then we need to teach dump_write() to restart and clear * TIF_SIGPENDING. */ - return signal_pending(current); + return fatal_signal_pending(current) || freezing(current); }

static void wait_for_dump_helpers(struct file *file)

From: Jens Axboe axboe@kernel.dk

stable inclusion from stable-v5.10.162 commit 788d0824269bef539fe31a785b1517882eafed93 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6BTWC CVE: CVE-2023-0240

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?h=v...

--------------------------------

No upstream commit exists.

This imports the io_uring codebase from 5.15.85, wholesale. Changes from that code base:

- Drop IOCB_ALLOC_CACHE, we don't have that in 5.10. - Drop MKDIRAT/SYMLINKAT/LINKAT. Would require further VFS backports, and we don't support these in 5.10 to begin with. - sock_from_file() old style calling convention. - Use compat_get_bitmap() only for CONFIG_COMPAT=y

Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- Makefile | 2 +- fs/Makefile | 2 - fs/io-wq.c | 1242 ----- include/linux/io_uring.h | 46 +- include/linux/sched.h | 3 + include/linux/syscalls.h | 2 +- include/trace/events/io_uring.h | 121 +- include/uapi/linux/io_uring.h | 115 +- io_uring/Makefile | 6 + io_uring/io-wq.c | 1398 +++++ {fs => io_uring}/io-wq.h | 47 +- {fs => io_uring}/io_uring.c | 9206 +++++++++++++++++-------------- kernel/exit.c | 2 +- kernel/fork.c | 1 + kernel/sched/core.c | 2 +- 15 files changed, 6714 insertions(+), 5481 deletions(-) delete mode 100644 fs/io-wq.c create mode 100644 io_uring/Makefile create mode 100644 io_uring/io-wq.c rename {fs => io_uring}/io-wq.h (81%) rename {fs => io_uring}/io_uring.c (51%)

diff --git a/Makefile b/Makefile index b606e8d3576f..aaa05a3e38d8 100644 --- a/Makefile +++ b/Makefile @@ -1129,7 +1129,7 @@ export MODORDER := $(extmod-prefix)modules.order export MODULES_NSDEPS := $(extmod-prefix)modules.nsdeps

ifeq ($(KBUILD_EXTMOD),) -core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/ +core-y += kernel/ certs/ mm/ fs/ ipc/ security/ crypto/ block/ io_uring/

vmlinux-dirs := $(patsubst %/,%,$(filter %/, \ $(core-y) $(core-m) $(drivers-y) $(drivers-m) \ diff --git a/fs/Makefile b/fs/Makefile index d91d30ba8b4e..720fccc8bffa 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -32,8 +32,6 @@ obj-$(CONFIG_TIMERFD) += timerfd.o obj-$(CONFIG_EVENTFD) += eventfd.o obj-$(CONFIG_USERFAULTFD) += userfaultfd.o obj-$(CONFIG_AIO) += aio.o -obj-$(CONFIG_IO_URING) += io_uring.o -obj-$(CONFIG_IO_WQ) += io-wq.o obj-$(CONFIG_FS_DAX) += dax.o obj-$(CONFIG_FS_ENCRYPTION) += crypto/ obj-$(CONFIG_FS_VERITY) += verity/ diff --git a/fs/io-wq.c b/fs/io-wq.c deleted file mode 100644 index 3d5fc76b92d0..000000000000 --- a/fs/io-wq.c +++ /dev/null @@ -1,1242 +0,0 @@ -// SPDX-License-Identifier: GPL-2.0 -/* - * Basic worker thread pool for io_uring - * - * Copyright (C) 2019 Jens Axboe - * - */ -#include <linux/kernel.h> -#include <linux/init.h> -#include <linux/errno.h> -#include <linux/sched/signal.h> -#include <linux/mm.h> -#include <linux/sched/mm.h> -#include <linux/percpu.h> -#include <linux/slab.h> -#include <linux/kthread.h> -#include <linux/rculist_nulls.h> -#include <linux/fs_struct.h> -#include <linux/task_work.h> -#include <linux/blk-cgroup.h> -#include <linux/audit.h> -#include <linux/cpu.h> - -#include "../kernel/sched/sched.h" -#include "io-wq.h" - -#define WORKER_IDLE_TIMEOUT (5 * HZ) - -enum { - IO_WORKER_F_UP = 1, /* up and active */ - IO_WORKER_F_RUNNING = 2, /* account as running */ - IO_WORKER_F_FREE = 4, /* worker on free list */ - IO_WORKER_F_FIXED = 8, /* static idle worker */ - IO_WORKER_F_BOUND = 16, /* is doing bounded work */ -}; - -enum { - IO_WQ_BIT_EXIT = 0, /* wq exiting */ - IO_WQ_BIT_CANCEL = 1, /* cancel work on list */ - IO_WQ_BIT_ERROR = 2, /* error on setup */ -}; - -enum { - IO_WQE_FLAG_STALLED = 1, /* stalled on hash */ -}; - -/* - * One for each thread in a wqe pool - */ -struct io_worker { - refcount_t ref; - unsigned flags; - struct hlist_nulls_node nulls_node; - struct list_head all_list; - struct task_struct *task; - struct io_wqe *wqe; - - struct io_wq_work *cur_work; - spinlock_t lock; - - struct rcu_head rcu; - struct mm_struct *mm; -#ifdef CONFIG_BLK_CGROUP - struct cgroup_subsys_state *blkcg_css; -#endif - const struct cred *cur_creds; - const struct cred *saved_creds; - struct files_struct *restore_files; - struct nsproxy *restore_nsproxy; - struct fs_struct *restore_fs; -}; - -#if BITS_PER_LONG == 64 -#define IO_WQ_HASH_ORDER 6 -#else -#define IO_WQ_HASH_ORDER 5 -#endif - -#define IO_WQ_NR_HASH_BUCKETS (1u << IO_WQ_HASH_ORDER) - -struct io_wqe_acct { - unsigned nr_workers; - unsigned max_workers; - atomic_t nr_running; -}; - -enum { - IO_WQ_ACCT_BOUND, - IO_WQ_ACCT_UNBOUND, -}; - -/* - * Per-node worker thread pool - */ -struct io_wqe { - struct { - raw_spinlock_t lock; - struct io_wq_work_list work_list; - unsigned long hash_map; - unsigned flags; - } ____cacheline_aligned_in_smp; - - int node; - struct io_wqe_acct acct[2]; - - struct hlist_nulls_head free_list; - struct list_head all_list; - - struct io_wq *wq; - struct io_wq_work *hash_tail[IO_WQ_NR_HASH_BUCKETS]; -}; - -/* - * Per io_wq state - */ -struct io_wq { - struct io_wqe **wqes; - unsigned long state; - - free_work_fn *free_work; - io_wq_work_fn *do_work; - - struct task_struct *manager; - struct user_struct *user; - refcount_t refs; - struct completion done; - - struct hlist_node cpuhp_node; - - refcount_t use_refs; -}; - -static enum cpuhp_state io_wq_online; - -static bool io_worker_get(struct io_worker *worker) -{ - return refcount_inc_not_zero(&worker->ref); -} - -static void io_worker_release(struct io_worker *worker) -{ - if (refcount_dec_and_test(&worker->ref)) - wake_up_process(worker->task); -} - -/* - * Note: drops the wqe->lock if returning true! The caller must re-acquire - * the lock in that case. Some callers need to restart handling if this - * happens, so we can't just re-acquire the lock on behalf of the caller. - */ -static bool __io_worker_unuse(struct io_wqe *wqe, struct io_worker *worker) -{ - bool dropped_lock = false; - - if (worker->saved_creds) { - revert_creds(worker->saved_creds); - worker->cur_creds = worker->saved_creds = NULL; - } - - if (current->files != worker->restore_files) { - __acquire(&wqe->lock); - raw_spin_unlock_irq(&wqe->lock); - dropped_lock = true; - - task_lock(current); - current->files = worker->restore_files; - current->nsproxy = worker->restore_nsproxy; - task_unlock(current); - } - - if (current->fs != worker->restore_fs) - current->fs = worker->restore_fs; - - /* - * If we have an active mm, we need to drop the wq lock before unusing - * it. If we do, return true and let the caller retry the idle loop. - */ - if (worker->mm) { - if (!dropped_lock) { - __acquire(&wqe->lock); - raw_spin_unlock_irq(&wqe->lock); - dropped_lock = true; - } - __set_current_state(TASK_RUNNING); - kthread_unuse_mm(worker->mm); - mmput(worker->mm); - worker->mm = NULL; - } - -#ifdef CONFIG_BLK_CGROUP - if (worker->blkcg_css) { - kthread_associate_blkcg(NULL); - worker->blkcg_css = NULL; - } -#endif - if (current->signal->rlim[RLIMIT_FSIZE].rlim_cur != RLIM_INFINITY) - current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY; - return dropped_lock; -} - -static inline struct io_wqe_acct *io_work_get_acct(struct io_wqe *wqe, - struct io_wq_work *work) -{ - if (work->flags & IO_WQ_WORK_UNBOUND) - return &wqe->acct[IO_WQ_ACCT_UNBOUND]; - - return &wqe->acct[IO_WQ_ACCT_BOUND]; -} - -static inline struct io_wqe_acct *io_wqe_get_acct(struct io_wqe *wqe, - struct io_worker *worker) -{ - if (worker->flags & IO_WORKER_F_BOUND) - return &wqe->acct[IO_WQ_ACCT_BOUND]; - - return &wqe->acct[IO_WQ_ACCT_UNBOUND]; -} - -static void io_worker_exit(struct io_worker *worker) -{ - struct io_wqe *wqe = worker->wqe; - struct io_wqe_acct *acct = io_wqe_get_acct(wqe, worker); - - /* - * If we're not at zero, someone else is holding a brief reference - * to the worker. Wait for that to go away. - */ - set_current_state(TASK_INTERRUPTIBLE); - if (!refcount_dec_and_test(&worker->ref)) - schedule(); - __set_current_state(TASK_RUNNING); - - preempt_disable(); - current->flags &= ~PF_IO_WORKER; - if (worker->flags & IO_WORKER_F_RUNNING) - atomic_dec(&acct->nr_running); - if (!(worker->flags & IO_WORKER_F_BOUND)) - atomic_dec(&wqe->wq->user->processes); - worker->flags = 0; - preempt_enable(); - - raw_spin_lock_irq(&wqe->lock); - hlist_nulls_del_rcu(&worker->nulls_node); - list_del_rcu(&worker->all_list); - if (__io_worker_unuse(wqe, worker)) { - __release(&wqe->lock); - raw_spin_lock_irq(&wqe->lock); - } - acct->nr_workers--; - raw_spin_unlock_irq(&wqe->lock); - - kfree_rcu(worker, rcu); - if (refcount_dec_and_test(&wqe->wq->refs)) - complete(&wqe->wq->done); -} - -static inline bool io_wqe_run_queue(struct io_wqe *wqe) - __must_hold(wqe->lock) -{ - if (!wq_list_empty(&wqe->work_list) && - !(wqe->flags & IO_WQE_FLAG_STALLED)) - return true; - return false; -} - -/* - * Check head of free list for an available worker. If one isn't available, - * caller must wake up the wq manager to create one. - */ -static bool io_wqe_activate_free_worker(struct io_wqe *wqe) - __must_hold(RCU) -{ - struct hlist_nulls_node *n; - struct io_worker *worker; - - n = rcu_dereference(hlist_nulls_first_rcu(&wqe->free_list)); - if (is_a_nulls(n)) - return false; - - worker = hlist_nulls_entry(n, struct io_worker, nulls_node); - if (io_worker_get(worker)) { - wake_up_process(worker->task); - io_worker_release(worker); - return true; - } - - return false; -} - -/* - * We need a worker. If we find a free one, we're good. If not, and we're - * below the max number of workers, wake up the manager to create one. - */ -static void io_wqe_wake_worker(struct io_wqe *wqe, struct io_wqe_acct *acct) -{ - bool ret; - - /* - * Most likely an attempt to queue unbounded work on an io_wq that - * wasn't setup with any unbounded workers. - */ - if (unlikely(!acct->max_workers)) - pr_warn_once("io-wq is not configured for unbound workers"); - - rcu_read_lock(); - ret = io_wqe_activate_free_worker(wqe); - rcu_read_unlock(); - - if (!ret && acct->nr_workers < acct->max_workers) - wake_up_process(wqe->wq->manager); -} - -static void io_wqe_inc_running(struct io_wqe *wqe, struct io_worker *worker) -{ - struct io_wqe_acct *acct = io_wqe_get_acct(wqe, worker); - - atomic_inc(&acct->nr_running); -} - -static void io_wqe_dec_running(struct io_wqe *wqe, struct io_worker *worker) - __must_hold(wqe->lock) -{ - struct io_wqe_acct *acct = io_wqe_get_acct(wqe, worker); - - if (atomic_dec_and_test(&acct->nr_running) && io_wqe_run_queue(wqe)) - io_wqe_wake_worker(wqe, acct); -} - -static void io_worker_start(struct io_wqe *wqe, struct io_worker *worker) -{ - allow_kernel_signal(SIGINT); - - current->flags |= PF_IO_WORKER; - - worker->flags |= (IO_WORKER_F_UP | IO_WORKER_F_RUNNING); - worker->restore_files = current->files; - worker->restore_nsproxy = current->nsproxy; - worker->restore_fs = current->fs; - io_wqe_inc_running(wqe, worker); -} - -/* - * Worker will start processing some work. Move it to the busy list, if - * it's currently on the freelist - */ -static void __io_worker_busy(struct io_wqe *wqe, struct io_worker *worker, - struct io_wq_work *work) - __must_hold(wqe->lock) -{ - bool worker_bound, work_bound; - - if (worker->flags & IO_WORKER_F_FREE) { - worker->flags &= ~IO_WORKER_F_FREE; - hlist_nulls_del_init_rcu(&worker->nulls_node); - } - - /* - * If worker is moving from bound to unbound (or vice versa), then - * ensure we update the running accounting. - */ - worker_bound = (worker->flags & IO_WORKER_F_BOUND) != 0; - work_bound = (work->flags & IO_WQ_WORK_UNBOUND) == 0; - if (worker_bound != work_bound) { - io_wqe_dec_running(wqe, worker); - if (work_bound) { - worker->flags |= IO_WORKER_F_BOUND; - wqe->acct[IO_WQ_ACCT_UNBOUND].nr_workers--; - wqe->acct[IO_WQ_ACCT_BOUND].nr_workers++; - atomic_dec(&wqe->wq->user->processes); - } else { - worker->flags &= ~IO_WORKER_F_BOUND; - wqe->acct[IO_WQ_ACCT_UNBOUND].nr_workers++; - wqe->acct[IO_WQ_ACCT_BOUND].nr_workers--; - atomic_inc(&wqe->wq->user->processes); - } - io_wqe_inc_running(wqe, worker); - } -} - -/* - * No work, worker going to sleep. Move to freelist, and unuse mm if we - * have one attached. Dropping the mm may potentially sleep, so we drop - * the lock in that case and return success. Since the caller has to - * retry the loop in that case (we changed task state), we don't regrab - * the lock if we return success. - */ -static bool __io_worker_idle(struct io_wqe *wqe, struct io_worker *worker) - __must_hold(wqe->lock) -{ - if (!(worker->flags & IO_WORKER_F_FREE)) { - worker->flags |= IO_WORKER_F_FREE; - hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list); - } - - return __io_worker_unuse(wqe, worker); -} - -static inline unsigned int io_get_work_hash(struct io_wq_work *work) -{ - return work->flags >> IO_WQ_HASH_SHIFT; -} - -static struct io_wq_work *io_get_next_work(struct io_wqe *wqe) - __must_hold(wqe->lock) -{ - struct io_wq_work_node *node, *prev; - struct io_wq_work *work, *tail; - unsigned int hash; - - wq_list_for_each(node, prev, &wqe->work_list) { - work = container_of(node, struct io_wq_work, list); - - /* not hashed, can run anytime */ - if (!io_wq_is_hashed(work)) { - wq_list_del(&wqe->work_list, node, prev); - return work; - } - - /* hashed, can run if not already running */ - hash = io_get_work_hash(work); - if (!(wqe->hash_map & BIT(hash))) { - wqe->hash_map |= BIT(hash); - /* all items with this hash lie in [work, tail] */ - tail = wqe->hash_tail[hash]; - wqe->hash_tail[hash] = NULL; - wq_list_cut(&wqe->work_list, &tail->list, prev); - return work; - } - } - - return NULL; -} - -static void io_wq_switch_mm(struct io_worker *worker, struct io_wq_work *work) -{ - if (worker->mm) { - kthread_unuse_mm(worker->mm); - mmput(worker->mm); - worker->mm = NULL; - } - - if (mmget_not_zero(work->identity->mm)) { - kthread_use_mm(work->identity->mm); - worker->mm = work->identity->mm; - return; - } - - /* failed grabbing mm, ensure work gets cancelled */ - work->flags |= IO_WQ_WORK_CANCEL; -} - -static inline void io_wq_switch_blkcg(struct io_worker *worker, - struct io_wq_work *work) -{ -#ifdef CONFIG_BLK_CGROUP - if (!(work->flags & IO_WQ_WORK_BLKCG)) - return; - if (work->identity->blkcg_css != worker->blkcg_css) { - kthread_associate_blkcg(work->identity->blkcg_css); - worker->blkcg_css = work->identity->blkcg_css; - } -#endif -} - -static void io_wq_switch_creds(struct io_worker *worker, - struct io_wq_work *work) -{ - const struct cred *old_creds = override_creds(work->identity->creds); - - worker->cur_creds = work->identity->creds; - if (worker->saved_creds) - put_cred(old_creds); /* creds set by previous switch */ - else - worker->saved_creds = old_creds; -} - -static void io_impersonate_work(struct io_worker *worker, - struct io_wq_work *work) -{ - if ((work->flags & IO_WQ_WORK_FILES) && - current->files != work->identity->files) { - task_lock(current); - current->files = work->identity->files; - current->nsproxy = work->identity->nsproxy; - task_unlock(current); - if (!work->identity->files) { - /* failed grabbing files, ensure work gets cancelled */ - work->flags |= IO_WQ_WORK_CANCEL; - } - } - if ((work->flags & IO_WQ_WORK_FS) && current->fs != work->identity->fs) - current->fs = work->identity->fs; - if ((work->flags & IO_WQ_WORK_MM) && work->identity->mm != worker->mm) - io_wq_switch_mm(worker, work); - if ((work->flags & IO_WQ_WORK_CREDS) && - worker->cur_creds != work->identity->creds) - io_wq_switch_creds(worker, work); - if (work->flags & IO_WQ_WORK_FSIZE) - current->signal->rlim[RLIMIT_FSIZE].rlim_cur = work->identity->fsize; - else if (current->signal->rlim[RLIMIT_FSIZE].rlim_cur != RLIM_INFINITY) - current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY; - io_wq_switch_blkcg(worker, work); -#ifdef CONFIG_AUDIT - current->loginuid = work->identity->loginuid; - current->sessionid = work->identity->sessionid; -#endif -} - -static void io_assign_current_work(struct io_worker *worker, - struct io_wq_work *work) -{ - if (work) { - /* flush pending signals before assigning new work */ - if (signal_pending(current)) - flush_signals(current); - cond_resched(); - } - -#ifdef CONFIG_AUDIT - current->loginuid = KUIDT_INIT(AUDIT_UID_UNSET); - current->sessionid = AUDIT_SID_UNSET; -#endif - - spin_lock_irq(&worker->lock); - worker->cur_work = work; - spin_unlock_irq(&worker->lock); -} - -static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work); - -static void io_worker_handle_work(struct io_worker *worker) - __releases(wqe->lock) -{ - struct io_wqe *wqe = worker->wqe; - struct io_wq *wq = wqe->wq; - - do { - struct io_wq_work *work; -get_next: - /* - * If we got some work, mark us as busy. If we didn't, but - * the list isn't empty, it means we stalled on hashed work. - * Mark us stalled so we don't keep looking for work when we - * can't make progress, any work completion or insertion will - * clear the stalled flag. - */ - work = io_get_next_work(wqe); - if (work) - __io_worker_busy(wqe, worker, work); - else if (!wq_list_empty(&wqe->work_list)) - wqe->flags |= IO_WQE_FLAG_STALLED; - - raw_spin_unlock_irq(&wqe->lock); - if (!work) - break; - io_assign_current_work(worker, work); - - /* handle a whole dependent link */ - do { - struct io_wq_work *old_work, *next_hashed, *linked; - unsigned int hash = io_get_work_hash(work); - - next_hashed = wq_next_work(work); - io_impersonate_work(worker, work); - /* - * OK to set IO_WQ_WORK_CANCEL even for uncancellable - * work, the worker function will do the right thing. - */ - if (test_bit(IO_WQ_BIT_CANCEL, &wq->state)) - work->flags |= IO_WQ_WORK_CANCEL; - - old_work = work; - linked = wq->do_work(work); - - work = next_hashed; - if (!work && linked && !io_wq_is_hashed(linked)) { - work = linked; - linked = NULL; - } - io_assign_current_work(worker, work); - wq->free_work(old_work); - - if (linked) - io_wqe_enqueue(wqe, linked); - - if (hash != -1U && !next_hashed) { - raw_spin_lock_irq(&wqe->lock); - wqe->hash_map &= ~BIT_ULL(hash); - wqe->flags &= ~IO_WQE_FLAG_STALLED; - /* skip unnecessary unlock-lock wqe->lock */ - if (!work) - goto get_next; - raw_spin_unlock_irq(&wqe->lock); - } - } while (work); - - raw_spin_lock_irq(&wqe->lock); - } while (1); -} - -static int io_wqe_worker(void *data) -{ - struct io_worker *worker = data; - struct io_wqe *wqe = worker->wqe; - struct io_wq *wq = wqe->wq; - - io_worker_start(wqe, worker); - - while (!test_bit(IO_WQ_BIT_EXIT, &wq->state)) { - set_current_state(TASK_INTERRUPTIBLE); -loop: - raw_spin_lock_irq(&wqe->lock); - if (io_wqe_run_queue(wqe)) { - __set_current_state(TASK_RUNNING); - io_worker_handle_work(worker); - goto loop; - } - /* drops the lock on success, retry */ - if (__io_worker_idle(wqe, worker)) { - __release(&wqe->lock); - goto loop; - } - raw_spin_unlock_irq(&wqe->lock); - if (signal_pending(current)) - flush_signals(current); - if (schedule_timeout(WORKER_IDLE_TIMEOUT)) - continue; - /* timed out, exit unless we're the fixed worker */ - if (test_bit(IO_WQ_BIT_EXIT, &wq->state) || - !(worker->flags & IO_WORKER_F_FIXED)) - break; - } - - if (test_bit(IO_WQ_BIT_EXIT, &wq->state)) { - raw_spin_lock_irq(&wqe->lock); - if (!wq_list_empty(&wqe->work_list)) - io_worker_handle_work(worker); - else - raw_spin_unlock_irq(&wqe->lock); - } - - io_worker_exit(worker); - return 0; -} - -/* - * Called when a worker is scheduled in. Mark us as currently running. - */ -void io_wq_worker_running(struct task_struct *tsk) -{ - struct io_worker *worker = kthread_data(tsk); - struct io_wqe *wqe = worker->wqe; - - if (!(worker->flags & IO_WORKER_F_UP)) - return; - if (worker->flags & IO_WORKER_F_RUNNING) - return; - worker->flags |= IO_WORKER_F_RUNNING; - io_wqe_inc_running(wqe, worker); -} - -/* - * Called when worker is going to sleep. If there are no workers currently - * running and we have work pending, wake up a free one or have the manager - * set one up. - */ -void io_wq_worker_sleeping(struct task_struct *tsk) -{ - struct io_worker *worker = kthread_data(tsk); - struct io_wqe *wqe = worker->wqe; - - if (!(worker->flags & IO_WORKER_F_UP)) - return; - if (!(worker->flags & IO_WORKER_F_RUNNING)) - return; - - worker->flags &= ~IO_WORKER_F_RUNNING; - - raw_spin_lock_irq(&wqe->lock); - io_wqe_dec_running(wqe, worker); - raw_spin_unlock_irq(&wqe->lock); -} - -static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index) -{ - struct io_wqe_acct *acct = &wqe->acct[index]; - struct io_worker *worker; - - worker = kzalloc_node(sizeof(*worker), GFP_KERNEL, wqe->node); - if (!worker) - return false; - - refcount_set(&worker->ref, 1); - worker->nulls_node.pprev = NULL; - worker->wqe = wqe; - spin_lock_init(&worker->lock); - - worker->task = kthread_create_on_node(io_wqe_worker, worker, wqe->node, - "io_wqe_worker-%d/%d", index, wqe->node); - if (IS_ERR(worker->task)) { - kfree(worker); - return false; - } - kthread_bind_mask(worker->task, cpumask_of_node(wqe->node)); - - raw_spin_lock_irq(&wqe->lock); - hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list); - list_add_tail_rcu(&worker->all_list, &wqe->all_list); - worker->flags |= IO_WORKER_F_FREE; - if (index == IO_WQ_ACCT_BOUND) - worker->flags |= IO_WORKER_F_BOUND; - if (!acct->nr_workers && (worker->flags & IO_WORKER_F_BOUND)) - worker->flags |= IO_WORKER_F_FIXED; - acct->nr_workers++; - raw_spin_unlock_irq(&wqe->lock); - - if (index == IO_WQ_ACCT_UNBOUND) - atomic_inc(&wq->user->processes); - - refcount_inc(&wq->refs); - wake_up_process(worker->task); - return true; -} - -static inline bool io_wqe_need_worker(struct io_wqe *wqe, int index) - __must_hold(wqe->lock) -{ - struct io_wqe_acct *acct = &wqe->acct[index]; - - /* if we have available workers or no work, no need */ - if (!hlist_nulls_empty(&wqe->free_list) || !io_wqe_run_queue(wqe)) - return false; - return acct->nr_workers < acct->max_workers; -} - -static bool io_wqe_worker_send_sig(struct io_worker *worker, void *data) -{ - send_sig(SIGINT, worker->task, 1); - return false; -} - -/* - * Iterate the passed in list and call the specific function for each - * worker that isn't exiting - */ -static bool io_wq_for_each_worker(struct io_wqe *wqe, - bool (*func)(struct io_worker *, void *), - void *data) -{ - struct io_worker *worker; - bool ret = false; - - list_for_each_entry_rcu(worker, &wqe->all_list, all_list) { - if (io_worker_get(worker)) { - /* no task if node is/was offline */ - if (worker->task) - ret = func(worker, data); - io_worker_release(worker); - if (ret) - break; - } - } - - return ret; -} - -static bool io_wq_worker_wake(struct io_worker *worker, void *data) -{ - wake_up_process(worker->task); - return false; -} - -/* - * Manager thread. Tasked with creating new workers, if we need them. - */ -static int io_wq_manager(void *data) -{ - struct io_wq *wq = data; - int node; - - /* create fixed workers */ - refcount_set(&wq->refs, 1); - for_each_node(node) { - if (!node_online(node)) - continue; - if (create_io_worker(wq, wq->wqes[node], IO_WQ_ACCT_BOUND)) - continue; - set_bit(IO_WQ_BIT_ERROR, &wq->state); - set_bit(IO_WQ_BIT_EXIT, &wq->state); - goto out; - } - - complete(&wq->done); - - while (!kthread_should_stop()) { - if (current->task_works) - task_work_run(); - - for_each_node(node) { - struct io_wqe *wqe = wq->wqes[node]; - bool fork_worker[2] = { false, false }; - - if (!node_online(node)) - continue; - - raw_spin_lock_irq(&wqe->lock); - if (io_wqe_need_worker(wqe, IO_WQ_ACCT_BOUND)) - fork_worker[IO_WQ_ACCT_BOUND] = true; - if (io_wqe_need_worker(wqe, IO_WQ_ACCT_UNBOUND)) - fork_worker[IO_WQ_ACCT_UNBOUND] = true; - raw_spin_unlock_irq(&wqe->lock); - if (fork_worker[IO_WQ_ACCT_BOUND]) - create_io_worker(wq, wqe, IO_WQ_ACCT_BOUND); - if (fork_worker[IO_WQ_ACCT_UNBOUND]) - create_io_worker(wq, wqe, IO_WQ_ACCT_UNBOUND); - } - set_current_state(TASK_INTERRUPTIBLE); - schedule_timeout(HZ); - } - - if (current->task_works) - task_work_run(); - -out: - if (refcount_dec_and_test(&wq->refs)) { - complete(&wq->done); - return 0; - } - /* if ERROR is set and we get here, we have workers to wake */ - if (test_bit(IO_WQ_BIT_ERROR, &wq->state)) { - rcu_read_lock(); - for_each_node(node) - io_wq_for_each_worker(wq->wqes[node], io_wq_worker_wake, NULL); - rcu_read_unlock(); - } - return 0; -} - -static bool io_wq_can_queue(struct io_wqe *wqe, struct io_wqe_acct *acct, - struct io_wq_work *work) -{ - bool free_worker; - - if (!(work->flags & IO_WQ_WORK_UNBOUND)) - return true; - if (atomic_read(&acct->nr_running)) - return true; - - rcu_read_lock(); - free_worker = !hlist_nulls_empty(&wqe->free_list); - rcu_read_unlock(); - if (free_worker) - return true; - - if (atomic_read(&wqe->wq->user->processes) >= acct->max_workers && - !(capable(CAP_SYS_RESOURCE) || capable(CAP_SYS_ADMIN))) - return false; - - return true; -} - -static void io_run_cancel(struct io_wq_work *work, struct io_wqe *wqe) -{ - struct io_wq *wq = wqe->wq; - - do { - struct io_wq_work *old_work = work; - - work->flags |= IO_WQ_WORK_CANCEL; - work = wq->do_work(work); - wq->free_work(old_work); - } while (work); -} - -static void io_wqe_insert_work(struct io_wqe *wqe, struct io_wq_work *work) -{ - unsigned int hash; - struct io_wq_work *tail; - - if (!io_wq_is_hashed(work)) { -append: - wq_list_add_tail(&work->list, &wqe->work_list); - return; - } - - hash = io_get_work_hash(work); - tail = wqe->hash_tail[hash]; - wqe->hash_tail[hash] = work; - if (!tail) - goto append; - - wq_list_add_after(&work->list, &tail->list, &wqe->work_list); -} - -static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work) -{ - struct io_wqe_acct *acct = io_work_get_acct(wqe, work); - bool do_wake; - unsigned long flags; - - /* - * Do early check to see if we need a new unbound worker, and if we do, - * if we're allowed to do so. This isn't 100% accurate as there's a - * gap between this check and incrementing the value, but that's OK. - * It's close enough to not be an issue, fork() has the same delay. - */ - if (unlikely(!io_wq_can_queue(wqe, acct, work))) { - io_run_cancel(work, wqe); - return; - } - - raw_spin_lock_irqsave(&wqe->lock, flags); - io_wqe_insert_work(wqe, work); - wqe->flags &= ~IO_WQE_FLAG_STALLED; - do_wake = (work->flags & IO_WQ_WORK_CONCURRENT) || - !atomic_read(&acct->nr_running); - raw_spin_unlock_irqrestore(&wqe->lock, flags); - - if (do_wake) - io_wqe_wake_worker(wqe, acct); -} - -void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work) -{ - struct io_wqe *wqe = wq->wqes[numa_node_id()]; - - io_wqe_enqueue(wqe, work); -} - -/* - * Work items that hash to the same value will not be done in parallel. - * Used to limit concurrent writes, generally hashed by inode. - */ -void io_wq_hash_work(struct io_wq_work *work, void *val) -{ - unsigned int bit; - - bit = hash_ptr(val, IO_WQ_HASH_ORDER); - work->flags |= (IO_WQ_WORK_HASHED | (bit << IO_WQ_HASH_SHIFT)); -} - -void io_wq_cancel_all(struct io_wq *wq) -{ - int node; - - set_bit(IO_WQ_BIT_CANCEL, &wq->state); - - rcu_read_lock(); - for_each_node(node) { - struct io_wqe *wqe = wq->wqes[node]; - - io_wq_for_each_worker(wqe, io_wqe_worker_send_sig, NULL); - } - rcu_read_unlock(); -} - -struct io_cb_cancel_data { - work_cancel_fn *fn; - void *data; - int nr_running; - int nr_pending; - bool cancel_all; -}; - -static bool io_wq_worker_cancel(struct io_worker *worker, void *data) -{ - struct io_cb_cancel_data *match = data; - unsigned long flags; - - /* - * Hold the lock to avoid ->cur_work going out of scope, caller - * may dereference the passed in work. - */ - spin_lock_irqsave(&worker->lock, flags); - if (worker->cur_work && - !(worker->cur_work->flags & IO_WQ_WORK_NO_CANCEL) && - match->fn(worker->cur_work, match->data)) { - send_sig(SIGINT, worker->task, 1); - match->nr_running++; - } - spin_unlock_irqrestore(&worker->lock, flags); - - return match->nr_running && !match->cancel_all; -} - -static inline void io_wqe_remove_pending(struct io_wqe *wqe, - struct io_wq_work *work, - struct io_wq_work_node *prev) -{ - unsigned int hash = io_get_work_hash(work); - struct io_wq_work *prev_work = NULL; - - if (io_wq_is_hashed(work) && work == wqe->hash_tail[hash]) { - if (prev) - prev_work = container_of(prev, struct io_wq_work, list); - if (prev_work && io_get_work_hash(prev_work) == hash) - wqe->hash_tail[hash] = prev_work; - else - wqe->hash_tail[hash] = NULL; - } - wq_list_del(&wqe->work_list, &work->list, prev); -} - -static void io_wqe_cancel_pending_work(struct io_wqe *wqe, - struct io_cb_cancel_data *match) -{ - struct io_wq_work_node *node, *prev; - struct io_wq_work *work; - unsigned long flags; - -retry: - raw_spin_lock_irqsave(&wqe->lock, flags); - wq_list_for_each(node, prev, &wqe->work_list) { - work = container_of(node, struct io_wq_work, list); - if (!match->fn(work, match->data)) - continue; - io_wqe_remove_pending(wqe, work, prev); - raw_spin_unlock_irqrestore(&wqe->lock, flags); - io_run_cancel(work, wqe); - match->nr_pending++; - if (!match->cancel_all) - return; - - /* not safe to continue after unlock */ - goto retry; - } - raw_spin_unlock_irqrestore(&wqe->lock, flags); -} - -static void io_wqe_cancel_running_work(struct io_wqe *wqe, - struct io_cb_cancel_data *match) -{ - rcu_read_lock(); - io_wq_for_each_worker(wqe, io_wq_worker_cancel, match); - rcu_read_unlock(); -} - -enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel, - void *data, bool cancel_all) -{ - struct io_cb_cancel_data match = { - .fn = cancel, - .data = data, - .cancel_all = cancel_all, - }; - int node; - - /* - * First check pending list, if we're lucky we can just remove it - * from there. CANCEL_OK means that the work is returned as-new, - * no completion will be posted for it. - */ - for_each_node(node) { - struct io_wqe *wqe = wq->wqes[node]; - - io_wqe_cancel_pending_work(wqe, &match); - if (match.nr_pending && !match.cancel_all) - return IO_WQ_CANCEL_OK; - } - - /* - * Now check if a free (going busy) or busy worker has the work - * currently running. If we find it there, we'll return CANCEL_RUNNING - * as an indication that we attempt to signal cancellation. The - * completion will run normally in this case. - */ - for_each_node(node) { - struct io_wqe *wqe = wq->wqes[node]; - - io_wqe_cancel_running_work(wqe, &match); - if (match.nr_running && !match.cancel_all) - return IO_WQ_CANCEL_RUNNING; - } - - if (match.nr_running) - return IO_WQ_CANCEL_RUNNING; - if (match.nr_pending) - return IO_WQ_CANCEL_OK; - return IO_WQ_CANCEL_NOTFOUND; -} - -struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data) -{ - int ret = -ENOMEM, node; - struct io_wq *wq; - - if (WARN_ON_ONCE(!data->free_work || !data->do_work)) - return ERR_PTR(-EINVAL); - if (WARN_ON_ONCE(!bounded)) - return ERR_PTR(-EINVAL); - - wq = kzalloc(sizeof(*wq), GFP_KERNEL); - if (!wq) - return ERR_PTR(-ENOMEM); - - wq->wqes = kcalloc(nr_node_ids, sizeof(struct io_wqe *), GFP_KERNEL); - if (!wq->wqes) - goto err_wq; - - ret = cpuhp_state_add_instance_nocalls(io_wq_online, &wq->cpuhp_node); - if (ret) - goto err_wqes; - - wq->free_work = data->free_work; - wq->do_work = data->do_work; - - /* caller must already hold a reference to this */ - wq->user = data->user; - - ret = -ENOMEM; - for_each_node(node) { - struct io_wqe *wqe; - int alloc_node = node; - - if (!node_online(alloc_node)) - alloc_node = NUMA_NO_NODE; - wqe = kzalloc_node(sizeof(struct io_wqe), GFP_KERNEL, alloc_node); - if (!wqe) - goto err; - wq->wqes[node] = wqe; - wqe->node = alloc_node; - wqe->acct[IO_WQ_ACCT_BOUND].max_workers = bounded; - atomic_set(&wqe->acct[IO_WQ_ACCT_BOUND].nr_running, 0); - if (wq->user) { - wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers = - task_rlimit(current, RLIMIT_NPROC); - } - atomic_set(&wqe->acct[IO_WQ_ACCT_UNBOUND].nr_running, 0); - wqe->wq = wq; - raw_spin_lock_init(&wqe->lock); - INIT_WQ_LIST(&wqe->work_list); - INIT_HLIST_NULLS_HEAD(&wqe->free_list, 0); - INIT_LIST_HEAD(&wqe->all_list); - } - - init_completion(&wq->done); - - wq->manager = kthread_create(io_wq_manager, wq, "io_wq_manager"); - if (!IS_ERR(wq->manager)) { - wake_up_process(wq->manager); - wait_for_completion(&wq->done); - if (test_bit(IO_WQ_BIT_ERROR, &wq->state)) { - ret = -ENOMEM; - goto err; - } - refcount_set(&wq->use_refs, 1); - reinit_completion(&wq->done); - return wq; - } - - ret = PTR_ERR(wq->manager); - complete(&wq->done); -err: - cpuhp_state_remove_instance_nocalls(io_wq_online, &wq->cpuhp_node); - for_each_node(node) - kfree(wq->wqes[node]); -err_wqes: - kfree(wq->wqes); -err_wq: - kfree(wq); - return ERR_PTR(ret); -} - -bool io_wq_get(struct io_wq *wq, struct io_wq_data *data) -{ - if (data->free_work != wq->free_work || data->do_work != wq->do_work) - return false; - - return refcount_inc_not_zero(&wq->use_refs); -} - -static void __io_wq_destroy(struct io_wq *wq) -{ - int node; - - cpuhp_state_remove_instance_nocalls(io_wq_online, &wq->cpuhp_node); - - set_bit(IO_WQ_BIT_EXIT, &wq->state); - if (wq->manager) - kthread_stop(wq->manager); - - rcu_read_lock(); - for_each_node(node) - io_wq_for_each_worker(wq->wqes[node], io_wq_worker_wake, NULL); - rcu_read_unlock(); - - wait_for_completion(&wq->done); - - for_each_node(node) - kfree(wq->wqes[node]); - kfree(wq->wqes); - kfree(wq); -} - -void io_wq_destroy(struct io_wq *wq) -{ - if (refcount_dec_and_test(&wq->use_refs)) - __io_wq_destroy(wq); -} - -struct task_struct *io_wq_get_task(struct io_wq *wq) -{ - return wq->manager; -} - -static bool io_wq_worker_affinity(struct io_worker *worker, void *data) -{ - struct task_struct *task = worker->task; - struct rq_flags rf; - struct rq *rq; - - rq = task_rq_lock(task, &rf); - do_set_cpus_allowed(task, cpumask_of_node(worker->wqe->node)); - task->flags |= PF_NO_SETAFFINITY; - task_rq_unlock(rq, task, &rf); - return false; -} - -static int io_wq_cpu_online(unsigned int cpu, struct hlist_node *node) -{ - struct io_wq *wq = hlist_entry_safe(node, struct io_wq, cpuhp_node); - int i; - - rcu_read_lock(); - for_each_node(i) - io_wq_for_each_worker(wq->wqes[i], io_wq_worker_affinity, NULL); - rcu_read_unlock(); - return 0; -} - -static __init int io_wq_init(void) -{ - int ret; - - ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "io-wq/online", - io_wq_cpu_online, NULL); - if (ret < 0) - return ret; - io_wq_online = ret; - return 0; -} -subsys_initcall(io_wq_init); diff --git a/include/linux/io_uring.h b/include/linux/io_uring.h index 35b2d845704d..649a4d7c241b 100644 --- a/include/linux/io_uring.h +++ b/include/linux/io_uring.h @@ -5,50 +5,20 @@ #include <linux/sched.h> #include <linux/xarray.h>

-struct io_identity { - struct files_struct *files; - struct mm_struct *mm; -#ifdef CONFIG_BLK_CGROUP - struct cgroup_subsys_state *blkcg_css; -#endif - const struct cred *creds; - struct nsproxy *nsproxy; - struct fs_struct *fs; - unsigned long fsize; -#ifdef CONFIG_AUDIT - kuid_t loginuid; - unsigned int sessionid; -#endif - refcount_t count; -}; - -struct io_uring_task { - /* submission side */ - struct xarray xa; - struct wait_queue_head wait; - struct file *last; - struct percpu_counter inflight; - struct io_identity __identity; - struct io_identity *identity; - atomic_t in_idle; - bool sqpoll; -}; - #if defined(CONFIG_IO_URING) struct sock *io_uring_get_socket(struct file *file); -void __io_uring_task_cancel(void); -void __io_uring_files_cancel(struct files_struct *files); +void __io_uring_cancel(bool cancel_all); void __io_uring_free(struct task_struct *tsk);

-static inline void io_uring_task_cancel(void) +static inline void io_uring_files_cancel(void) { - if (current->io_uring && !xa_empty(&current->io_uring->xa)) - __io_uring_task_cancel(); + if (current->io_uring) + __io_uring_cancel(false); } -static inline void io_uring_files_cancel(struct files_struct *files) +static inline void io_uring_task_cancel(void) { - if (current->io_uring && !xa_empty(&current->io_uring->xa)) - __io_uring_files_cancel(files); + if (current->io_uring) + __io_uring_cancel(true); } static inline void io_uring_free(struct task_struct *tsk) { @@ -63,7 +33,7 @@ static inline struct sock *io_uring_get_socket(struct file *file) static inline void io_uring_task_cancel(void) { } -static inline void io_uring_files_cancel(struct files_struct *files) +static inline void io_uring_files_cancel(void) { } static inline void io_uring_free(struct task_struct *tsk) diff --git a/include/linux/sched.h b/include/linux/sched.h index a84372945f9e..961acc4fa738 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -925,6 +925,9 @@ struct task_struct { /* CLONE_CHILD_CLEARTID: */ int __user *clear_child_tid;

+ /* PF_IO_WORKER */ + void *pf_io_worker; + u64 utime; u64 stime; #ifdef CONFIG_ARCH_HAS_SCALED_CPUTIME diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index aea0ce9f3b74..a058c96cf213 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -341,7 +341,7 @@ asmlinkage long sys_io_uring_setup(u32 entries, struct io_uring_params __user *p); asmlinkage long sys_io_uring_enter(unsigned int fd, u32 to_submit, u32 min_complete, u32 flags, - const sigset_t __user *sig, size_t sigsz); + const void __user *argp, size_t argsz); asmlinkage long sys_io_uring_register(unsigned int fd, unsigned int op, void __user *arg, unsigned int nr_args);

diff --git a/include/trace/events/io_uring.h b/include/trace/events/io_uring.h index 9f0d3b7d56b0..0dd30de00e5b 100644 --- a/include/trace/events/io_uring.h +++ b/include/trace/events/io_uring.h @@ -12,11 +12,11 @@ struct io_wq_work; /** * io_uring_create - called after a new io_uring context was prepared * - * @fd: corresponding file descriptor - * @ctx: pointer to a ring context structure + * @fd: corresponding file descriptor + * @ctx: pointer to a ring context structure * @sq_entries: actual SQ size * @cq_entries: actual CQ size - * @flags: SQ ring flags, provided to io_uring_setup(2) + * @flags: SQ ring flags, provided to io_uring_setup(2) * * Allows to trace io_uring creation and provide pointer to a context, that can * be used later to find correlated events. @@ -49,15 +49,15 @@ TRACE_EVENT(io_uring_create, );

/** - * io_uring_register - called after a buffer/file/eventfd was succesfully + * io_uring_register - called after a buffer/file/eventfd was successfully * registered for a ring * - * @ctx: pointer to a ring context structure - * @opcode: describes which operation to perform + * @ctx: pointer to a ring context structure + * @opcode: describes which operation to perform * @nr_user_files: number of registered files * @nr_user_bufs: number of registered buffers * @cq_ev_fd: whether eventfs registered or not - * @ret: return code + * @ret: return code * * Allows to trace fixed files/buffers/eventfds, that could be registered to * avoid an overhead of getting references to them for every operation. This @@ -142,16 +142,16 @@ TRACE_EVENT(io_uring_queue_async_work, TP_ARGS(ctx, rw, req, work, flags),

TP_STRUCT__entry ( - __field( void *, ctx ) - __field( int, rw ) - __field( void *, req ) + __field( void *, ctx ) + __field( int, rw ) + __field( void *, req ) __field( struct io_wq_work *, work ) __field( unsigned int, flags ) ),

TP_fast_assign( __entry->ctx = ctx; - __entry->rw = rw; + __entry->rw = rw; __entry->req = req; __entry->work = work; __entry->flags = flags; @@ -196,10 +196,10 @@ TRACE_EVENT(io_uring_defer,

/** * io_uring_link - called before the io_uring request added into link_list of - * another request + * another request * - * @ctx: pointer to a ring context structure - * @req: pointer to a linked request + * @ctx: pointer to a ring context structure + * @req: pointer to a linked request * @target_req: pointer to a previous request, that would contain @req * * Allows to track linked requests, to understand dependencies between requests @@ -212,8 +212,8 @@ TRACE_EVENT(io_uring_link, TP_ARGS(ctx, req, target_req),

TP_STRUCT__entry ( - __field( void *, ctx ) - __field( void *, req ) + __field( void *, ctx ) + __field( void *, req ) __field( void *, target_req ) ),

@@ -244,7 +244,7 @@ TRACE_EVENT(io_uring_cqring_wait, TP_ARGS(ctx, min_events),

TP_STRUCT__entry ( - __field( void *, ctx ) + __field( void *, ctx ) __field( int, min_events ) ),

@@ -272,7 +272,7 @@ TRACE_EVENT(io_uring_fail_link, TP_ARGS(req, link),

TP_STRUCT__entry ( - __field( void *, req ) + __field( void *, req ) __field( void *, link ) ),

@@ -290,38 +290,42 @@ TRACE_EVENT(io_uring_fail_link, * @ctx: pointer to a ring context structure * @user_data: user data associated with the request * @res: result of the request + * @cflags: completion flags * */ TRACE_EVENT(io_uring_complete,

- TP_PROTO(void *ctx, u64 user_data, long res), + TP_PROTO(void *ctx, u64 user_data, int res, unsigned cflags),

- TP_ARGS(ctx, user_data, res), + TP_ARGS(ctx, user_data, res, cflags),

TP_STRUCT__entry ( __field( void *, ctx ) __field( u64, user_data ) - __field( long, res ) + __field( int, res ) + __field( unsigned, cflags ) ),

TP_fast_assign( __entry->ctx = ctx; __entry->user_data = user_data; __entry->res = res; + __entry->cflags = cflags; ),

- TP_printk("ring %p, user_data 0x%llx, result %ld", + TP_printk("ring %p, user_data 0x%llx, result %d, cflags %x", __entry->ctx, (unsigned long long)__entry->user_data, - __entry->res) + __entry->res, __entry->cflags) );

- /** * io_uring_submit_sqe - called before submitting one SQE * * @ctx: pointer to a ring context structure + * @req: pointer to a submitted request * @opcode: opcode of request * @user_data: user data associated with the request + * @flags request flags * @force_nonblock: whether a context blocking or not * @sq_thread: true if sq_thread has submitted this SQE * @@ -330,41 +334,60 @@ TRACE_EVENT(io_uring_complete, */ TRACE_EVENT(io_uring_submit_sqe,

- TP_PROTO(void *ctx, u8 opcode, u64 user_data, bool force_nonblock, - bool sq_thread), + TP_PROTO(void *ctx, void *req, u8 opcode, u64 user_data, u32 flags, + bool force_nonblock, bool sq_thread),

- TP_ARGS(ctx, opcode, user_data, force_nonblock, sq_thread), + TP_ARGS(ctx, req, opcode, user_data, flags, force_nonblock, sq_thread),

TP_STRUCT__entry ( __field( void *, ctx ) + __field( void *, req ) __field( u8, opcode ) __field( u64, user_data ) + __field( u32, flags ) __field( bool, force_nonblock ) __field( bool, sq_thread ) ),

TP_fast_assign( __entry->ctx = ctx; + __entry->req = req; __entry->opcode = opcode; __entry->user_data = user_data; + __entry->flags = flags; __entry->force_nonblock = force_nonblock; __entry->sq_thread = sq_thread; ),

- TP_printk("ring %p, op %d, data 0x%llx, non block %d, sq_thread %d", - __entry->ctx, __entry->opcode, - (unsigned long long) __entry->user_data, - __entry->force_nonblock, __entry->sq_thread) + TP_printk("ring %p, req %p, op %d, data 0x%llx, flags %u, " + "non block %d, sq_thread %d", __entry->ctx, __entry->req, + __entry->opcode, (unsigned long long)__entry->user_data, + __entry->flags, __entry->force_nonblock, __entry->sq_thread) );

+/* + * io_uring_poll_arm - called after arming a poll wait if successful + * + * @ctx: pointer to a ring context structure + * @req: pointer to the armed request + * @opcode: opcode of request + * @user_data: user data associated with the request + * @mask: request poll events mask + * @events: registered events of interest + * + * Allows to track which fds are waiting for and what are the events of + * interest. + */ TRACE_EVENT(io_uring_poll_arm,

- TP_PROTO(void *ctx, u8 opcode, u64 user_data, int mask, int events), + TP_PROTO(void *ctx, void *req, u8 opcode, u64 user_data, + int mask, int events),

- TP_ARGS(ctx, opcode, user_data, mask, events), + TP_ARGS(ctx, req, opcode, user_data, mask, events),

TP_STRUCT__entry ( __field( void *, ctx ) + __field( void *, req ) __field( u8, opcode ) __field( u64, user_data ) __field( int, mask ) @@ -373,16 +396,17 @@ TRACE_EVENT(io_uring_poll_arm,

TP_fast_assign( __entry->ctx = ctx; + __entry->req = req; __entry->opcode = opcode; __entry->user_data = user_data; __entry->mask = mask; __entry->events = events; ),

- TP_printk("ring %p, op %d, data 0x%llx, mask 0x%x, events 0x%x", - __entry->ctx, __entry->opcode, - (unsigned long long) __entry->user_data, - __entry->mask, __entry->events) + TP_printk("ring %p, req %p, op %d, data 0x%llx, mask 0x%x, events 0x%x", + __entry->ctx, __entry->req, __entry->opcode, + (unsigned long long) __entry->user_data, + __entry->mask, __entry->events) );

TRACE_EVENT(io_uring_poll_wake, @@ -437,27 +461,40 @@ TRACE_EVENT(io_uring_task_add, __entry->mask) );

+/* + * io_uring_task_run - called when task_work_run() executes the poll events + * notification callbacks + * + * @ctx: pointer to a ring context structure + * @req: pointer to the armed request + * @opcode: opcode of request + * @user_data: user data associated with the request + * + * Allows to track when notified poll events are processed + */ TRACE_EVENT(io_uring_task_run,

- TP_PROTO(void *ctx, u8 opcode, u64 user_data), + TP_PROTO(void *ctx, void *req, u8 opcode, u64 user_data),

- TP_ARGS(ctx, opcode, user_data), + TP_ARGS(ctx, req, opcode, user_data),

TP_STRUCT__entry ( __field( void *, ctx ) + __field( void *, req ) __field( u8, opcode ) __field( u64, user_data ) ),

TP_fast_assign( __entry->ctx = ctx; + __entry->req = req; __entry->opcode = opcode; __entry->user_data = user_data; ),

- TP_printk("ring %p, op %d, data 0x%llx", - __entry->ctx, __entry->opcode, - (unsigned long long) __entry->user_data) + TP_printk("ring %p, req %p, op %d, data 0x%llx", + __entry->ctx, __entry->req, __entry->opcode, + (unsigned long long) __entry->user_data) );

#endif /* _TRACE_IO_URING_H */ diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index 98d8e06dea22..6481db937002 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -42,23 +42,25 @@ struct io_uring_sqe { __u32 statx_flags; __u32 fadvise_advice; __u32 splice_flags; + __u32 rename_flags; + __u32 unlink_flags; + __u32 hardlink_flags; }; __u64 user_data; /* data to be passed back at completion time */ + /* pack this to avoid bogus arm OABI complaints */ union { - struct { - /* pack this to avoid bogus arm OABI complaints */ - union { - /* index into fixed buffers, if used */ - __u16 buf_index; - /* for grouped buffer selection */ - __u16 buf_group; - } __attribute__((packed)); - /* personality to use, if used */ - __u16 personality; - __s32 splice_fd_in; - }; - __u64 __pad2[3]; + /* index into fixed buffers, if used */ + __u16 buf_index; + /* for grouped buffer selection */ + __u16 buf_group; + } __attribute__((packed)); + /* personality to use, if used */ + __u16 personality; + union { + __s32 splice_fd_in; + __u32 file_index; }; + __u64 __pad2[2]; };

enum { @@ -132,6 +134,9 @@ enum { IORING_OP_PROVIDE_BUFFERS, IORING_OP_REMOVE_BUFFERS, IORING_OP_TEE, + IORING_OP_SHUTDOWN, + IORING_OP_RENAMEAT, + IORING_OP_UNLINKAT,

/* this goes last, obviously */ IORING_OP_LAST, @@ -145,14 +150,34 @@ enum { /* * sqe->timeout_flags */ -#define IORING_TIMEOUT_ABS (1U << 0) - +#define IORING_TIMEOUT_ABS (1U << 0) +#define IORING_TIMEOUT_UPDATE (1U << 1) +#define IORING_TIMEOUT_BOOTTIME (1U << 2) +#define IORING_TIMEOUT_REALTIME (1U << 3) +#define IORING_LINK_TIMEOUT_UPDATE (1U << 4) +#define IORING_TIMEOUT_CLOCK_MASK (IORING_TIMEOUT_BOOTTIME | IORING_TIMEOUT_REALTIME) +#define IORING_TIMEOUT_UPDATE_MASK (IORING_TIMEOUT_UPDATE | IORING_LINK_TIMEOUT_UPDATE) /* * sqe->splice_flags * extends splice(2) flags */ #define SPLICE_F_FD_IN_FIXED (1U << 31) /* the last bit of __u32 */

+/* + * POLL_ADD flags. Note that since sqe->poll_events is the flag space, the + * command flags for POLL_ADD are stored in sqe->len. + * + * IORING_POLL_ADD_MULTI Multishot poll. Sets IORING_CQE_F_MORE if + * the poll handler will continue to report + * CQEs on behalf of the same SQE. + * + * IORING_POLL_UPDATE Update existing poll request, matching + * sqe->addr as the old user_data field. + */ +#define IORING_POLL_ADD_MULTI (1U << 0) +#define IORING_POLL_UPDATE_EVENTS (1U << 1) +#define IORING_POLL_UPDATE_USER_DATA (1U << 2) + /* * IO completion data structure (Completion Queue Entry) */ @@ -166,8 +191,10 @@ struct io_uring_cqe { * cqe->flags * * IORING_CQE_F_BUFFER If set, the upper 16 bits are the buffer ID + * IORING_CQE_F_MORE If set, parent SQE will generate more CQE entries */ #define IORING_CQE_F_BUFFER (1U << 0) +#define IORING_CQE_F_MORE (1U << 1)

enum { IORING_CQE_BUFFER_SHIFT = 16, @@ -226,6 +253,7 @@ struct io_cqring_offsets { #define IORING_ENTER_GETEVENTS (1U << 0) #define IORING_ENTER_SQ_WAKEUP (1U << 1) #define IORING_ENTER_SQ_WAIT (1U << 2) +#define IORING_ENTER_EXT_ARG (1U << 3)

/* * Passed in for io_uring_setup(2). Copied back with updated info on success @@ -253,6 +281,10 @@ struct io_uring_params { #define IORING_FEAT_CUR_PERSONALITY (1U << 4) #define IORING_FEAT_FAST_POLL (1U << 5) #define IORING_FEAT_POLL_32BITS (1U << 6) +#define IORING_FEAT_SQPOLL_NONFIXED (1U << 7) +#define IORING_FEAT_EXT_ARG (1U << 8) +#define IORING_FEAT_NATIVE_WORKERS (1U << 9) +#define IORING_FEAT_RSRC_TAGS (1U << 10)

/* * io_uring_register(2) opcodes and arguments @@ -272,16 +304,62 @@ enum { IORING_REGISTER_RESTRICTIONS = 11, IORING_REGISTER_ENABLE_RINGS = 12,

+ /* extended with tagging */ + IORING_REGISTER_FILES2 = 13, + IORING_REGISTER_FILES_UPDATE2 = 14, + IORING_REGISTER_BUFFERS2 = 15, + IORING_REGISTER_BUFFERS_UPDATE = 16, + + /* set/clear io-wq thread affinities */ + IORING_REGISTER_IOWQ_AFF = 17, + IORING_UNREGISTER_IOWQ_AFF = 18, + + /* set/get max number of io-wq workers */ + IORING_REGISTER_IOWQ_MAX_WORKERS = 19, + /* this goes last */ IORING_REGISTER_LAST };

+/* io-wq worker categories */ +enum { + IO_WQ_BOUND, + IO_WQ_UNBOUND, +}; + +/* deprecated, see struct io_uring_rsrc_update */ struct io_uring_files_update { __u32 offset; __u32 resv; __aligned_u64 /* __s32 * */ fds; };

+struct io_uring_rsrc_register { + __u32 nr; + __u32 resv; + __u64 resv2; + __aligned_u64 data; + __aligned_u64 tags; +}; + +struct io_uring_rsrc_update { + __u32 offset; + __u32 resv; + __aligned_u64 data; +}; + +struct io_uring_rsrc_update2 { + __u32 offset; + __u32 resv; + __aligned_u64 data; + __aligned_u64 tags; + __u32 nr; + __u32 resv2; +}; + +/* Skip updating fd indexes set to this value in the fd table */ +#define IORING_REGISTER_FILES_SKIP (-2) + #define IO_URING_OP_SUPPORTED (1U << 0)

struct io_uring_probe_op { @@ -329,4 +407,11 @@ enum { IORING_RESTRICTION_LAST };

+struct io_uring_getevents_arg { + __u64 sigmask; + __u32 sigmask_sz; + __u32 pad; + __u64 ts; +}; + #endif diff --git a/io_uring/Makefile b/io_uring/Makefile new file mode 100644 index 000000000000..3680425df947 --- /dev/null +++ b/io_uring/Makefile @@ -0,0 +1,6 @@ +# SPDX-License-Identifier: GPL-2.0 +# +# Makefile for io_uring + +obj-$(CONFIG_IO_URING) += io_uring.o +obj-$(CONFIG_IO_WQ) += io-wq.o diff --git a/io_uring/io-wq.c b/io_uring/io-wq.c new file mode 100644 index 000000000000..6031fb319d87 --- /dev/null +++ b/io_uring/io-wq.c @@ -0,0 +1,1398 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Basic worker thread pool for io_uring + * + * Copyright (C) 2019 Jens Axboe + * + */ +#include <linux/kernel.h> +#include <linux/init.h> +#include <linux/errno.h> +#include <linux/sched/signal.h> +#include <linux/percpu.h> +#include <linux/slab.h> +#include <linux/rculist_nulls.h> +#include <linux/cpu.h> +#include <linux/tracehook.h> +#include <uapi/linux/io_uring.h> + +#include "io-wq.h" + +#define WORKER_IDLE_TIMEOUT (5 * HZ) + +enum { + IO_WORKER_F_UP = 1, /* up and active */ + IO_WORKER_F_RUNNING = 2, /* account as running */ + IO_WORKER_F_FREE = 4, /* worker on free list */ + IO_WORKER_F_BOUND = 8, /* is doing bounded work */ +}; + +enum { + IO_WQ_BIT_EXIT = 0, /* wq exiting */ +}; + +enum { + IO_ACCT_STALLED_BIT = 0, /* stalled on hash */ +}; + +/* + * One for each thread in a wqe pool + */ +struct io_worker { + refcount_t ref; + unsigned flags; + struct hlist_nulls_node nulls_node; + struct list_head all_list; + struct task_struct *task; + struct io_wqe *wqe; + + struct io_wq_work *cur_work; + spinlock_t lock; + + struct completion ref_done; + + unsigned long create_state; + struct callback_head create_work; + int create_index; + + union { + struct rcu_head rcu; + struct work_struct work; + }; +}; + +#if BITS_PER_LONG == 64 +#define IO_WQ_HASH_ORDER 6 +#else +#define IO_WQ_HASH_ORDER 5 +#endif + +#define IO_WQ_NR_HASH_BUCKETS (1u << IO_WQ_HASH_ORDER) + +struct io_wqe_acct { + unsigned nr_workers; + unsigned max_workers; + int index; + atomic_t nr_running; + struct io_wq_work_list work_list; + unsigned long flags; +}; + +enum { + IO_WQ_ACCT_BOUND, + IO_WQ_ACCT_UNBOUND, + IO_WQ_ACCT_NR, +}; + +/* + * Per-node worker thread pool + */ +struct io_wqe { + raw_spinlock_t lock; + struct io_wqe_acct acct[2]; + + int node; + + struct hlist_nulls_head free_list; + struct list_head all_list; + + struct wait_queue_entry wait; + + struct io_wq *wq; + struct io_wq_work *hash_tail[IO_WQ_NR_HASH_BUCKETS]; + + cpumask_var_t cpu_mask; +}; + +/* + * Per io_wq state + */ +struct io_wq { + unsigned long state; + + free_work_fn *free_work; + io_wq_work_fn *do_work; + + struct io_wq_hash *hash; + + atomic_t worker_refs; + struct completion worker_done; + + struct hlist_node cpuhp_node; + + struct task_struct *task; + + struct io_wqe *wqes[]; +}; + +static enum cpuhp_state io_wq_online; + +struct io_cb_cancel_data { + work_cancel_fn *fn; + void *data; + int nr_running; + int nr_pending; + bool cancel_all; +}; + +static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index); +static void io_wqe_dec_running(struct io_worker *worker); +static bool io_acct_cancel_pending_work(struct io_wqe *wqe, + struct io_wqe_acct *acct, + struct io_cb_cancel_data *match); +static void create_worker_cb(struct callback_head *cb); +static void io_wq_cancel_tw_create(struct io_wq *wq); + +static bool io_worker_get(struct io_worker *worker) +{ + return refcount_inc_not_zero(&worker->ref); +} + +static void io_worker_release(struct io_worker *worker) +{ + if (refcount_dec_and_test(&worker->ref)) + complete(&worker->ref_done); +} + +static inline struct io_wqe_acct *io_get_acct(struct io_wqe *wqe, bool bound) +{ + return &wqe->acct[bound ? IO_WQ_ACCT_BOUND : IO_WQ_ACCT_UNBOUND]; +} + +static inline struct io_wqe_acct *io_work_get_acct(struct io_wqe *wqe, + struct io_wq_work *work) +{ + return io_get_acct(wqe, !(work->flags & IO_WQ_WORK_UNBOUND)); +} + +static inline struct io_wqe_acct *io_wqe_get_acct(struct io_worker *worker) +{ + return io_get_acct(worker->wqe, worker->flags & IO_WORKER_F_BOUND); +} + +static void io_worker_ref_put(struct io_wq *wq) +{ + if (atomic_dec_and_test(&wq->worker_refs)) + complete(&wq->worker_done); +} + +static void io_worker_cancel_cb(struct io_worker *worker) +{ + struct io_wqe_acct *acct = io_wqe_get_acct(worker); + struct io_wqe *wqe = worker->wqe; + struct io_wq *wq = wqe->wq; + + atomic_dec(&acct->nr_running); + raw_spin_lock(&worker->wqe->lock); + acct->nr_workers--; + raw_spin_unlock(&worker->wqe->lock); + io_worker_ref_put(wq); + clear_bit_unlock(0, &worker->create_state); + io_worker_release(worker); +} + +static bool io_task_worker_match(struct callback_head *cb, void *data) +{ + struct io_worker *worker; + + if (cb->func != create_worker_cb) + return false; + worker = container_of(cb, struct io_worker, create_work); + return worker == data; +} + +static void io_worker_exit(struct io_worker *worker) +{ + struct io_wqe *wqe = worker->wqe; + struct io_wq *wq = wqe->wq; + + while (1) { + struct callback_head *cb = task_work_cancel_match(wq->task, + io_task_worker_match, worker); + + if (!cb) + break; + io_worker_cancel_cb(worker); + } + + if (refcount_dec_and_test(&worker->ref)) + complete(&worker->ref_done); + wait_for_completion(&worker->ref_done); + + raw_spin_lock(&wqe->lock); + if (worker->flags & IO_WORKER_F_FREE) + hlist_nulls_del_rcu(&worker->nulls_node); + list_del_rcu(&worker->all_list); + preempt_disable(); + io_wqe_dec_running(worker); + worker->flags = 0; + current->flags &= ~PF_IO_WORKER; + preempt_enable(); + raw_spin_unlock(&wqe->lock); + + kfree_rcu(worker, rcu); + io_worker_ref_put(wqe->wq); + do_exit(0); +} + +static inline bool io_acct_run_queue(struct io_wqe_acct *acct) +{ + if (!wq_list_empty(&acct->work_list) && + !test_bit(IO_ACCT_STALLED_BIT, &acct->flags)) + return true; + return false; +} + +/* + * Check head of free list for an available worker. If one isn't available, + * caller must create one. + */ +static bool io_wqe_activate_free_worker(struct io_wqe *wqe, + struct io_wqe_acct *acct) + __must_hold(RCU) +{ + struct hlist_nulls_node *n; + struct io_worker *worker; + + /* + * Iterate free_list and see if we can find an idle worker to + * activate. If a given worker is on the free_list but in the process + * of exiting, keep trying. + */ + hlist_nulls_for_each_entry_rcu(worker, n, &wqe->free_list, nulls_node) { + if (!io_worker_get(worker)) + continue; + if (io_wqe_get_acct(worker) != acct) { + io_worker_release(worker); + continue; + } + if (wake_up_process(worker->task)) { + io_worker_release(worker); + return true; + } + io_worker_release(worker); + } + + return false; +} + +/* + * We need a worker. If we find a free one, we're good. If not, and we're + * below the max number of workers, create one. + */ +static bool io_wqe_create_worker(struct io_wqe *wqe, struct io_wqe_acct *acct) +{ + /* + * Most likely an attempt to queue unbounded work on an io_wq that + * wasn't setup with any unbounded workers. + */ + if (unlikely(!acct->max_workers)) + pr_warn_once("io-wq is not configured for unbound workers"); + + raw_spin_lock(&wqe->lock); + if (acct->nr_workers >= acct->max_workers) { + raw_spin_unlock(&wqe->lock); + return true; + } + acct->nr_workers++; + raw_spin_unlock(&wqe->lock); + atomic_inc(&acct->nr_running); + atomic_inc(&wqe->wq->worker_refs); + return create_io_worker(wqe->wq, wqe, acct->index); +} + +static void io_wqe_inc_running(struct io_worker *worker) +{ + struct io_wqe_acct *acct = io_wqe_get_acct(worker); + + atomic_inc(&acct->nr_running); +} + +static void create_worker_cb(struct callback_head *cb) +{ + struct io_worker *worker; + struct io_wq *wq; + struct io_wqe *wqe; + struct io_wqe_acct *acct; + bool do_create = false; + + worker = container_of(cb, struct io_worker, create_work); + wqe = worker->wqe; + wq = wqe->wq; + acct = &wqe->acct[worker->create_index]; + raw_spin_lock(&wqe->lock); + if (acct->nr_workers < acct->max_workers) { + acct->nr_workers++; + do_create = true; + } + raw_spin_unlock(&wqe->lock); + if (do_create) { + create_io_worker(wq, wqe, worker->create_index); + } else { + atomic_dec(&acct->nr_running); + io_worker_ref_put(wq); + } + clear_bit_unlock(0, &worker->create_state); + io_worker_release(worker); +} + +static bool io_queue_worker_create(struct io_worker *worker, + struct io_wqe_acct *acct, + task_work_func_t func) +{ + struct io_wqe *wqe = worker->wqe; + struct io_wq *wq = wqe->wq; + + /* raced with exit, just ignore create call */ + if (test_bit(IO_WQ_BIT_EXIT, &wq->state)) + goto fail; + if (!io_worker_get(worker)) + goto fail; + /* + * create_state manages ownership of create_work/index. We should + * only need one entry per worker, as the worker going to sleep + * will trigger the condition, and waking will clear it once it + * runs the task_work. + */ + if (test_bit(0, &worker->create_state) || + test_and_set_bit_lock(0, &worker->create_state)) + goto fail_release; + + atomic_inc(&wq->worker_refs); + init_task_work(&worker->create_work, func); + worker->create_index = acct->index; + if (!task_work_add(wq->task, &worker->create_work, TWA_SIGNAL)) { + /* + * EXIT may have been set after checking it above, check after + * adding the task_work and remove any creation item if it is + * now set. wq exit does that too, but we can have added this + * work item after we canceled in io_wq_exit_workers(). + */ + if (test_bit(IO_WQ_BIT_EXIT, &wq->state)) + io_wq_cancel_tw_create(wq); + io_worker_ref_put(wq); + return true; + } + io_worker_ref_put(wq); + clear_bit_unlock(0, &worker->create_state); +fail_release: + io_worker_release(worker); +fail: + atomic_dec(&acct->nr_running); + io_worker_ref_put(wq); + return false; +} + +static void io_wqe_dec_running(struct io_worker *worker) + __must_hold(wqe->lock) +{ + struct io_wqe_acct *acct = io_wqe_get_acct(worker); + struct io_wqe *wqe = worker->wqe; + + if (!(worker->flags & IO_WORKER_F_UP)) + return; + + if (atomic_dec_and_test(&acct->nr_running) && io_acct_run_queue(acct)) { + atomic_inc(&acct->nr_running); + atomic_inc(&wqe->wq->worker_refs); + raw_spin_unlock(&wqe->lock); + io_queue_worker_create(worker, acct, create_worker_cb); + raw_spin_lock(&wqe->lock); + } +} + +/* + * Worker will start processing some work. Move it to the busy list, if + * it's currently on the freelist + */ +static void __io_worker_busy(struct io_wqe *wqe, struct io_worker *worker, + struct io_wq_work *work) + __must_hold(wqe->lock) +{ + if (worker->flags & IO_WORKER_F_FREE) { + worker->flags &= ~IO_WORKER_F_FREE; + hlist_nulls_del_init_rcu(&worker->nulls_node); + } +} + +/* + * No work, worker going to sleep. Move to freelist, and unuse mm if we + * have one attached. Dropping the mm may potentially sleep, so we drop + * the lock in that case and return success. Since the caller has to + * retry the loop in that case (we changed task state), we don't regrab + * the lock if we return success. + */ +static void __io_worker_idle(struct io_wqe *wqe, struct io_worker *worker) + __must_hold(wqe->lock) +{ + if (!(worker->flags & IO_WORKER_F_FREE)) { + worker->flags |= IO_WORKER_F_FREE; + hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list); + } +} + +static inline unsigned int io_get_work_hash(struct io_wq_work *work) +{ + return work->flags >> IO_WQ_HASH_SHIFT; +} + +static bool io_wait_on_hash(struct io_wqe *wqe, unsigned int hash) +{ + struct io_wq *wq = wqe->wq; + bool ret = false; + + spin_lock_irq(&wq->hash->wait.lock); + if (list_empty(&wqe->wait.entry)) { + __add_wait_queue(&wq->hash->wait, &wqe->wait); + if (!test_bit(hash, &wq->hash->map)) { + __set_current_state(TASK_RUNNING); + list_del_init(&wqe->wait.entry); + ret = true; + } + } + spin_unlock_irq(&wq->hash->wait.lock); + return ret; +} + +static struct io_wq_work *io_get_next_work(struct io_wqe_acct *acct, + struct io_worker *worker) + __must_hold(wqe->lock) +{ + struct io_wq_work_node *node, *prev; + struct io_wq_work *work, *tail; + unsigned int stall_hash = -1U; + struct io_wqe *wqe = worker->wqe; + + wq_list_for_each(node, prev, &acct->work_list) { + unsigned int hash; + + work = container_of(node, struct io_wq_work, list); + + /* not hashed, can run anytime */ + if (!io_wq_is_hashed(work)) { + wq_list_del(&acct->work_list, node, prev); + return work; + } + + hash = io_get_work_hash(work); + /* all items with this hash lie in [work, tail] */ + tail = wqe->hash_tail[hash]; + + /* hashed, can run if not already running */ + if (!test_and_set_bit(hash, &wqe->wq->hash->map)) { + wqe->hash_tail[hash] = NULL; + wq_list_cut(&acct->work_list, &tail->list, prev); + return work; + } + if (stall_hash == -1U) + stall_hash = hash; + /* fast forward to a next hash, for-each will fix up @prev */ + node = &tail->list; + } + + if (stall_hash != -1U) { + bool unstalled; + + /* + * Set this before dropping the lock to avoid racing with new + * work being added and clearing the stalled bit. + */ + set_bit(IO_ACCT_STALLED_BIT, &acct->flags); + raw_spin_unlock(&wqe->lock); + unstalled = io_wait_on_hash(wqe, stall_hash); + raw_spin_lock(&wqe->lock); + if (unstalled) { + clear_bit(IO_ACCT_STALLED_BIT, &acct->flags); + if (wq_has_sleeper(&wqe->wq->hash->wait)) + wake_up(&wqe->wq->hash->wait); + } + } + + return NULL; +} + +static bool io_flush_signals(void) +{ + if (unlikely(test_thread_flag(TIF_NOTIFY_SIGNAL))) { + __set_current_state(TASK_RUNNING); + tracehook_notify_signal(); + return true; + } + return false; +} + +static void io_assign_current_work(struct io_worker *worker, + struct io_wq_work *work) +{ + if (work) { + io_flush_signals(); + cond_resched(); + } + + spin_lock(&worker->lock); + worker->cur_work = work; + spin_unlock(&worker->lock); +} + +static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work); + +static void io_worker_handle_work(struct io_worker *worker) + __releases(wqe->lock) +{ + struct io_wqe_acct *acct = io_wqe_get_acct(worker); + struct io_wqe *wqe = worker->wqe; + struct io_wq *wq = wqe->wq; + bool do_kill = test_bit(IO_WQ_BIT_EXIT, &wq->state); + + do { + struct io_wq_work *work; +get_next: + /* + * If we got some work, mark us as busy. If we didn't, but + * the list isn't empty, it means we stalled on hashed work. + * Mark us stalled so we don't keep looking for work when we + * can't make progress, any work completion or insertion will + * clear the stalled flag. + */ + work = io_get_next_work(acct, worker); + if (work) + __io_worker_busy(wqe, worker, work); + + raw_spin_unlock(&wqe->lock); + if (!work) + break; + io_assign_current_work(worker, work); + __set_current_state(TASK_RUNNING); + + /* handle a whole dependent link */ + do { + struct io_wq_work *next_hashed, *linked; + unsigned int hash = io_get_work_hash(work); + + next_hashed = wq_next_work(work); + + if (unlikely(do_kill) && (work->flags & IO_WQ_WORK_UNBOUND)) + work->flags |= IO_WQ_WORK_CANCEL; + wq->do_work(work); + io_assign_current_work(worker, NULL); + + linked = wq->free_work(work); + work = next_hashed; + if (!work && linked && !io_wq_is_hashed(linked)) { + work = linked; + linked = NULL; + } + io_assign_current_work(worker, work); + if (linked) + io_wqe_enqueue(wqe, linked); + + if (hash != -1U && !next_hashed) { + /* serialize hash clear with wake_up() */ + spin_lock_irq(&wq->hash->wait.lock); + clear_bit(hash, &wq->hash->map); + clear_bit(IO_ACCT_STALLED_BIT, &acct->flags); + spin_unlock_irq(&wq->hash->wait.lock); + if (wq_has_sleeper(&wq->hash->wait)) + wake_up(&wq->hash->wait); + raw_spin_lock(&wqe->lock); + /* skip unnecessary unlock-lock wqe->lock */ + if (!work) + goto get_next; + raw_spin_unlock(&wqe->lock); + } + } while (work); + + raw_spin_lock(&wqe->lock); + } while (1); +} + +static int io_wqe_worker(void *data) +{ + struct io_worker *worker = data; + struct io_wqe_acct *acct = io_wqe_get_acct(worker); + struct io_wqe *wqe = worker->wqe; + struct io_wq *wq = wqe->wq; + bool last_timeout = false; + char buf[TASK_COMM_LEN]; + + worker->flags |= (IO_WORKER_F_UP | IO_WORKER_F_RUNNING); + + snprintf(buf, sizeof(buf), "iou-wrk-%d", wq->task->pid); + set_task_comm(current, buf); + + while (!test_bit(IO_WQ_BIT_EXIT, &wq->state)) { + long ret; + + set_current_state(TASK_INTERRUPTIBLE); +loop: + raw_spin_lock(&wqe->lock); + if (io_acct_run_queue(acct)) { + io_worker_handle_work(worker); + goto loop; + } + /* timed out, exit unless we're the last worker */ + if (last_timeout && acct->nr_workers > 1) { + acct->nr_workers--; + raw_spin_unlock(&wqe->lock); + __set_current_state(TASK_RUNNING); + break; + } + last_timeout = false; + __io_worker_idle(wqe, worker); + raw_spin_unlock(&wqe->lock); + if (io_flush_signals()) + continue; + ret = schedule_timeout(WORKER_IDLE_TIMEOUT); + if (signal_pending(current)) { + struct ksignal ksig; + + if (!get_signal(&ksig)) + continue; + break; + } + last_timeout = !ret; + } + + if (test_bit(IO_WQ_BIT_EXIT, &wq->state)) { + raw_spin_lock(&wqe->lock); + io_worker_handle_work(worker); + } + + io_worker_exit(worker); + return 0; +} + +/* + * Called when a worker is scheduled in. Mark us as currently running. + */ +void io_wq_worker_running(struct task_struct *tsk) +{ + struct io_worker *worker = tsk->pf_io_worker; + + if (!worker) + return; + if (!(worker->flags & IO_WORKER_F_UP)) + return; + if (worker->flags & IO_WORKER_F_RUNNING) + return; + worker->flags |= IO_WORKER_F_RUNNING; + io_wqe_inc_running(worker); +} + +/* + * Called when worker is going to sleep. If there are no workers currently + * running and we have work pending, wake up a free one or create a new one. + */ +void io_wq_worker_sleeping(struct task_struct *tsk) +{ + struct io_worker *worker = tsk->pf_io_worker; + + if (!worker) + return; + if (!(worker->flags & IO_WORKER_F_UP)) + return; + if (!(worker->flags & IO_WORKER_F_RUNNING)) + return; + + worker->flags &= ~IO_WORKER_F_RUNNING; + + raw_spin_lock(&worker->wqe->lock); + io_wqe_dec_running(worker); + raw_spin_unlock(&worker->wqe->lock); +} + +static void io_init_new_worker(struct io_wqe *wqe, struct io_worker *worker, + struct task_struct *tsk) +{ + tsk->pf_io_worker = worker; + worker->task = tsk; + set_cpus_allowed_ptr(tsk, wqe->cpu_mask); + tsk->flags |= PF_NO_SETAFFINITY; + + raw_spin_lock(&wqe->lock); + hlist_nulls_add_head_rcu(&worker->nulls_node, &wqe->free_list); + list_add_tail_rcu(&worker->all_list, &wqe->all_list); + worker->flags |= IO_WORKER_F_FREE; + raw_spin_unlock(&wqe->lock); + wake_up_new_task(tsk); +} + +static bool io_wq_work_match_all(struct io_wq_work *work, void *data) +{ + return true; +} + +static inline bool io_should_retry_thread(long err) +{ + /* + * Prevent perpetual task_work retry, if the task (or its group) is + * exiting. + */ + if (fatal_signal_pending(current)) + return false; + + switch (err) { + case -EAGAIN: + case -ERESTARTSYS: + case -ERESTARTNOINTR: + case -ERESTARTNOHAND: + return true; + default: + return false; + } +} + +static void create_worker_cont(struct callback_head *cb) +{ + struct io_worker *worker; + struct task_struct *tsk; + struct io_wqe *wqe; + + worker = container_of(cb, struct io_worker, create_work); + clear_bit_unlock(0, &worker->create_state); + wqe = worker->wqe; + tsk = create_io_thread(io_wqe_worker, worker, wqe->node); + if (!IS_ERR(tsk)) { + io_init_new_worker(wqe, worker, tsk); + io_worker_release(worker); + return; + } else if (!io_should_retry_thread(PTR_ERR(tsk))) { + struct io_wqe_acct *acct = io_wqe_get_acct(worker); + + atomic_dec(&acct->nr_running); + raw_spin_lock(&wqe->lock); + acct->nr_workers--; + if (!acct->nr_workers) { + struct io_cb_cancel_data match = { + .fn = io_wq_work_match_all, + .cancel_all = true, + }; + + while (io_acct_cancel_pending_work(wqe, acct, &match)) + raw_spin_lock(&wqe->lock); + } + raw_spin_unlock(&wqe->lock); + io_worker_ref_put(wqe->wq); + kfree(worker); + return; + } + + /* re-create attempts grab a new worker ref, drop the existing one */ + io_worker_release(worker); + schedule_work(&worker->work); +} + +static void io_workqueue_create(struct work_struct *work) +{ + struct io_worker *worker = container_of(work, struct io_worker, work); + struct io_wqe_acct *acct = io_wqe_get_acct(worker); + + if (!io_queue_worker_create(worker, acct, create_worker_cont)) + kfree(worker); +} + +static bool create_io_worker(struct io_wq *wq, struct io_wqe *wqe, int index) +{ + struct io_wqe_acct *acct = &wqe->acct[index]; + struct io_worker *worker; + struct task_struct *tsk; + + __set_current_state(TASK_RUNNING); + + worker = kzalloc_node(sizeof(*worker), GFP_KERNEL, wqe->node); + if (!worker) { +fail: + atomic_dec(&acct->nr_running); + raw_spin_lock(&wqe->lock); + acct->nr_workers--; + raw_spin_unlock(&wqe->lock); + io_worker_ref_put(wq); + return false; + } + + refcount_set(&worker->ref, 1); + worker->wqe = wqe; + spin_lock_init(&worker->lock); + init_completion(&worker->ref_done); + + if (index == IO_WQ_ACCT_BOUND) + worker->flags |= IO_WORKER_F_BOUND; + + tsk = create_io_thread(io_wqe_worker, worker, wqe->node); + if (!IS_ERR(tsk)) { + io_init_new_worker(wqe, worker, tsk); + } else if (!io_should_retry_thread(PTR_ERR(tsk))) { + kfree(worker); + goto fail; + } else { + INIT_WORK(&worker->work, io_workqueue_create); + schedule_work(&worker->work); + } + + return true; +} + +/* + * Iterate the passed in list and call the specific function for each + * worker that isn't exiting + */ +static bool io_wq_for_each_worker(struct io_wqe *wqe, + bool (*func)(struct io_worker *, void *), + void *data) +{ + struct io_worker *worker; + bool ret = false; + + list_for_each_entry_rcu(worker, &wqe->all_list, all_list) { + if (io_worker_get(worker)) { + /* no task if node is/was offline */ + if (worker->task) + ret = func(worker, data); + io_worker_release(worker); + if (ret) + break; + } + } + + return ret; +} + +static bool io_wq_worker_wake(struct io_worker *worker, void *data) +{ + set_notify_signal(worker->task); + wake_up_process(worker->task); + return false; +} + +static void io_run_cancel(struct io_wq_work *work, struct io_wqe *wqe) +{ + struct io_wq *wq = wqe->wq; + + do { + work->flags |= IO_WQ_WORK_CANCEL; + wq->do_work(work); + work = wq->free_work(work); + } while (work); +} + +static void io_wqe_insert_work(struct io_wqe *wqe, struct io_wq_work *work) +{ + struct io_wqe_acct *acct = io_work_get_acct(wqe, work); + unsigned int hash; + struct io_wq_work *tail; + + if (!io_wq_is_hashed(work)) { +append: + wq_list_add_tail(&work->list, &acct->work_list); + return; + } + + hash = io_get_work_hash(work); + tail = wqe->hash_tail[hash]; + wqe->hash_tail[hash] = work; + if (!tail) + goto append; + + wq_list_add_after(&work->list, &tail->list, &acct->work_list); +} + +static bool io_wq_work_match_item(struct io_wq_work *work, void *data) +{ + return work == data; +} + +static void io_wqe_enqueue(struct io_wqe *wqe, struct io_wq_work *work) +{ + struct io_wqe_acct *acct = io_work_get_acct(wqe, work); + unsigned work_flags = work->flags; + bool do_create; + + /* + * If io-wq is exiting for this task, or if the request has explicitly + * been marked as one that should not get executed, cancel it here. + */ + if (test_bit(IO_WQ_BIT_EXIT, &wqe->wq->state) || + (work->flags & IO_WQ_WORK_CANCEL)) { + io_run_cancel(work, wqe); + return; + } + + raw_spin_lock(&wqe->lock); + io_wqe_insert_work(wqe, work); + clear_bit(IO_ACCT_STALLED_BIT, &acct->flags); + + rcu_read_lock(); + do_create = !io_wqe_activate_free_worker(wqe, acct); + rcu_read_unlock(); + + raw_spin_unlock(&wqe->lock); + + if (do_create && ((work_flags & IO_WQ_WORK_CONCURRENT) || + !atomic_read(&acct->nr_running))) { + bool did_create; + + did_create = io_wqe_create_worker(wqe, acct); + if (likely(did_create)) + return; + + raw_spin_lock(&wqe->lock); + /* fatal condition, failed to create the first worker */ + if (!acct->nr_workers) { + struct io_cb_cancel_data match = { + .fn = io_wq_work_match_item, + .data = work, + .cancel_all = false, + }; + + if (io_acct_cancel_pending_work(wqe, acct, &match)) + raw_spin_lock(&wqe->lock); + } + raw_spin_unlock(&wqe->lock); + } +} + +void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work) +{ + struct io_wqe *wqe = wq->wqes[numa_node_id()]; + + io_wqe_enqueue(wqe, work); +} + +/* + * Work items that hash to the same value will not be done in parallel. + * Used to limit concurrent writes, generally hashed by inode. + */ +void io_wq_hash_work(struct io_wq_work *work, void *val) +{ + unsigned int bit; + + bit = hash_ptr(val, IO_WQ_HASH_ORDER); + work->flags |= (IO_WQ_WORK_HASHED | (bit << IO_WQ_HASH_SHIFT)); +} + +static bool io_wq_worker_cancel(struct io_worker *worker, void *data) +{ + struct io_cb_cancel_data *match = data; + + /* + * Hold the lock to avoid ->cur_work going out of scope, caller + * may dereference the passed in work. + */ + spin_lock(&worker->lock); + if (worker->cur_work && + match->fn(worker->cur_work, match->data)) { + set_notify_signal(worker->task); + match->nr_running++; + } + spin_unlock(&worker->lock); + + return match->nr_running && !match->cancel_all; +} + +static inline void io_wqe_remove_pending(struct io_wqe *wqe, + struct io_wq_work *work, + struct io_wq_work_node *prev) +{ + struct io_wqe_acct *acct = io_work_get_acct(wqe, work); + unsigned int hash = io_get_work_hash(work); + struct io_wq_work *prev_work = NULL; + + if (io_wq_is_hashed(work) && work == wqe->hash_tail[hash]) { + if (prev) + prev_work = container_of(prev, struct io_wq_work, list); + if (prev_work && io_get_work_hash(prev_work) == hash) + wqe->hash_tail[hash] = prev_work; + else + wqe->hash_tail[hash] = NULL; + } + wq_list_del(&acct->work_list, &work->list, prev); +} + +static bool io_acct_cancel_pending_work(struct io_wqe *wqe, + struct io_wqe_acct *acct, + struct io_cb_cancel_data *match) + __releases(wqe->lock) +{ + struct io_wq_work_node *node, *prev; + struct io_wq_work *work; + + wq_list_for_each(node, prev, &acct->work_list) { + work = container_of(node, struct io_wq_work, list); + if (!match->fn(work, match->data)) + continue; + io_wqe_remove_pending(wqe, work, prev); + raw_spin_unlock(&wqe->lock); + io_run_cancel(work, wqe); + match->nr_pending++; + /* not safe to continue after unlock */ + return true; + } + + return false; +} + +static void io_wqe_cancel_pending_work(struct io_wqe *wqe, + struct io_cb_cancel_data *match) +{ + int i; +retry: + raw_spin_lock(&wqe->lock); + for (i = 0; i < IO_WQ_ACCT_NR; i++) { + struct io_wqe_acct *acct = io_get_acct(wqe, i == 0); + + if (io_acct_cancel_pending_work(wqe, acct, match)) { + if (match->cancel_all) + goto retry; + return; + } + } + raw_spin_unlock(&wqe->lock); +} + +static void io_wqe_cancel_running_work(struct io_wqe *wqe, + struct io_cb_cancel_data *match) +{ + rcu_read_lock(); + io_wq_for_each_worker(wqe, io_wq_worker_cancel, match); + rcu_read_unlock(); +} + +enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel, + void *data, bool cancel_all) +{ + struct io_cb_cancel_data match = { + .fn = cancel, + .data = data, + .cancel_all = cancel_all, + }; + int node; + + /* + * First check pending list, if we're lucky we can just remove it + * from there. CANCEL_OK means that the work is returned as-new, + * no completion will be posted for it. + */ + for_each_node(node) { + struct io_wqe *wqe = wq->wqes[node]; + + io_wqe_cancel_pending_work(wqe, &match); + if (match.nr_pending && !match.cancel_all) + return IO_WQ_CANCEL_OK; + } + + /* + * Now check if a free (going busy) or busy worker has the work + * currently running. If we find it there, we'll return CANCEL_RUNNING + * as an indication that we attempt to signal cancellation. The + * completion will run normally in this case. + */ + for_each_node(node) { + struct io_wqe *wqe = wq->wqes[node]; + + io_wqe_cancel_running_work(wqe, &match); + if (match.nr_running && !match.cancel_all) + return IO_WQ_CANCEL_RUNNING; + } + + if (match.nr_running) + return IO_WQ_CANCEL_RUNNING; + if (match.nr_pending) + return IO_WQ_CANCEL_OK; + return IO_WQ_CANCEL_NOTFOUND; +} + +static int io_wqe_hash_wake(struct wait_queue_entry *wait, unsigned mode, + int sync, void *key) +{ + struct io_wqe *wqe = container_of(wait, struct io_wqe, wait); + int i; + + list_del_init(&wait->entry); + + rcu_read_lock(); + for (i = 0; i < IO_WQ_ACCT_NR; i++) { + struct io_wqe_acct *acct = &wqe->acct[i]; + + if (test_and_clear_bit(IO_ACCT_STALLED_BIT, &acct->flags)) + io_wqe_activate_free_worker(wqe, acct); + } + rcu_read_unlock(); + return 1; +} + +struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data) +{ + int ret, node, i; + struct io_wq *wq; + + if (WARN_ON_ONCE(!data->free_work || !data->do_work)) + return ERR_PTR(-EINVAL); + if (WARN_ON_ONCE(!bounded)) + return ERR_PTR(-EINVAL); + + wq = kzalloc(struct_size(wq, wqes, nr_node_ids), GFP_KERNEL); + if (!wq) + return ERR_PTR(-ENOMEM); + ret = cpuhp_state_add_instance_nocalls(io_wq_online, &wq->cpuhp_node); + if (ret) + goto err_wq; + + refcount_inc(&data->hash->refs); + wq->hash = data->hash; + wq->free_work = data->free_work; + wq->do_work = data->do_work; + + ret = -ENOMEM; + for_each_node(node) { + struct io_wqe *wqe; + int alloc_node = node; + + if (!node_online(alloc_node)) + alloc_node = NUMA_NO_NODE; + wqe = kzalloc_node(sizeof(struct io_wqe), GFP_KERNEL, alloc_node); + if (!wqe) + goto err; + wq->wqes[node] = wqe; + if (!alloc_cpumask_var(&wqe->cpu_mask, GFP_KERNEL)) + goto err; + cpumask_copy(wqe->cpu_mask, cpumask_of_node(node)); + wqe->node = alloc_node; + wqe->acct[IO_WQ_ACCT_BOUND].max_workers = bounded; + wqe->acct[IO_WQ_ACCT_UNBOUND].max_workers = + task_rlimit(current, RLIMIT_NPROC); + INIT_LIST_HEAD(&wqe->wait.entry); + wqe->wait.func = io_wqe_hash_wake; + for (i = 0; i < IO_WQ_ACCT_NR; i++) { + struct io_wqe_acct *acct = &wqe->acct[i]; + + acct->index = i; + atomic_set(&acct->nr_running, 0); + INIT_WQ_LIST(&acct->work_list); + } + wqe->wq = wq; + raw_spin_lock_init(&wqe->lock); + INIT_HLIST_NULLS_HEAD(&wqe->free_list, 0); + INIT_LIST_HEAD(&wqe->all_list); + } + + wq->task = get_task_struct(data->task); + atomic_set(&wq->worker_refs, 1); + init_completion(&wq->worker_done); + return wq; +err: + io_wq_put_hash(data->hash); + cpuhp_state_remove_instance_nocalls(io_wq_online, &wq->cpuhp_node); + for_each_node(node) { + if (!wq->wqes[node]) + continue; + free_cpumask_var(wq->wqes[node]->cpu_mask); + kfree(wq->wqes[node]); + } +err_wq: + kfree(wq); + return ERR_PTR(ret); +} + +static bool io_task_work_match(struct callback_head *cb, void *data) +{ + struct io_worker *worker; + + if (cb->func != create_worker_cb && cb->func != create_worker_cont) + return false; + worker = container_of(cb, struct io_worker, create_work); + return worker->wqe->wq == data; +} + +void io_wq_exit_start(struct io_wq *wq) +{ + set_bit(IO_WQ_BIT_EXIT, &wq->state); +} + +static void io_wq_cancel_tw_create(struct io_wq *wq) +{ + struct callback_head *cb; + + while ((cb = task_work_cancel_match(wq->task, io_task_work_match, wq)) != NULL) { + struct io_worker *worker; + + worker = container_of(cb, struct io_worker, create_work); + io_worker_cancel_cb(worker); + } +} + +static void io_wq_exit_workers(struct io_wq *wq) +{ + int node; + + if (!wq->task) + return; + + io_wq_cancel_tw_create(wq); + + rcu_read_lock(); + for_each_node(node) { + struct io_wqe *wqe = wq->wqes[node]; + + io_wq_for_each_worker(wqe, io_wq_worker_wake, NULL); + } + rcu_read_unlock(); + io_worker_ref_put(wq); + wait_for_completion(&wq->worker_done); + + for_each_node(node) { + spin_lock_irq(&wq->hash->wait.lock); + list_del_init(&wq->wqes[node]->wait.entry); + spin_unlock_irq(&wq->hash->wait.lock); + } + put_task_struct(wq->task); + wq->task = NULL; +} + +static void io_wq_destroy(struct io_wq *wq) +{ + int node; + + cpuhp_state_remove_instance_nocalls(io_wq_online, &wq->cpuhp_node); + + for_each_node(node) { + struct io_wqe *wqe = wq->wqes[node]; + struct io_cb_cancel_data match = { + .fn = io_wq_work_match_all, + .cancel_all = true, + }; + io_wqe_cancel_pending_work(wqe, &match); + free_cpumask_var(wqe->cpu_mask); + kfree(wqe); + } + io_wq_put_hash(wq->hash); + kfree(wq); +} + +void io_wq_put_and_exit(struct io_wq *wq) +{ + WARN_ON_ONCE(!test_bit(IO_WQ_BIT_EXIT, &wq->state)); + + io_wq_exit_workers(wq); + io_wq_destroy(wq); +} + +struct online_data { + unsigned int cpu; + bool online; +}; + +static bool io_wq_worker_affinity(struct io_worker *worker, void *data) +{ + struct online_data *od = data; + + if (od->online) + cpumask_set_cpu(od->cpu, worker->wqe->cpu_mask); + else + cpumask_clear_cpu(od->cpu, worker->wqe->cpu_mask); + return false; +} + +static int __io_wq_cpu_online(struct io_wq *wq, unsigned int cpu, bool online) +{ + struct online_data od = { + .cpu = cpu, + .online = online + }; + int i; + + rcu_read_lock(); + for_each_node(i) + io_wq_for_each_worker(wq->wqes[i], io_wq_worker_affinity, &od); + rcu_read_unlock(); + return 0; +} + +static int io_wq_cpu_online(unsigned int cpu, struct hlist_node *node) +{ + struct io_wq *wq = hlist_entry_safe(node, struct io_wq, cpuhp_node); + + return __io_wq_cpu_online(wq, cpu, true); +} + +static int io_wq_cpu_offline(unsigned int cpu, struct hlist_node *node) +{ + struct io_wq *wq = hlist_entry_safe(node, struct io_wq, cpuhp_node); + + return __io_wq_cpu_online(wq, cpu, false); +} + +int io_wq_cpu_affinity(struct io_wq *wq, cpumask_var_t mask) +{ + int i; + + rcu_read_lock(); + for_each_node(i) { + struct io_wqe *wqe = wq->wqes[i]; + + if (mask) + cpumask_copy(wqe->cpu_mask, mask); + else + cpumask_copy(wqe->cpu_mask, cpumask_of_node(i)); + } + rcu_read_unlock(); + return 0; +} + +/* + * Set max number of unbounded workers, returns old value. If new_count is 0, + * then just return the old value. + */ +int io_wq_max_workers(struct io_wq *wq, int *new_count) +{ + int prev[IO_WQ_ACCT_NR]; + bool first_node = true; + int i, node; + + BUILD_BUG_ON((int) IO_WQ_ACCT_BOUND != (int) IO_WQ_BOUND); + BUILD_BUG_ON((int) IO_WQ_ACCT_UNBOUND != (int) IO_WQ_UNBOUND); + BUILD_BUG_ON((int) IO_WQ_ACCT_NR != 2); + + for (i = 0; i < 2; i++) { + if (new_count[i] > task_rlimit(current, RLIMIT_NPROC)) + new_count[i] = task_rlimit(current, RLIMIT_NPROC); + } + + for (i = 0; i < IO_WQ_ACCT_NR; i++) + prev[i] = 0; + + rcu_read_lock(); + for_each_node(node) { + struct io_wqe *wqe = wq->wqes[node]; + struct io_wqe_acct *acct; + + raw_spin_lock(&wqe->lock); + for (i = 0; i < IO_WQ_ACCT_NR; i++) { + acct = &wqe->acct[i]; + if (first_node) + prev[i] = max_t(int, acct->max_workers, prev[i]); + if (new_count[i]) + acct->max_workers = new_count[i]; + } + raw_spin_unlock(&wqe->lock); + first_node = false; + } + rcu_read_unlock(); + + for (i = 0; i < IO_WQ_ACCT_NR; i++) + new_count[i] = prev[i]; + + return 0; +} + +static __init int io_wq_init(void) +{ + int ret; + + ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN, "io-wq/online", + io_wq_cpu_online, io_wq_cpu_offline); + if (ret < 0) + return ret; + io_wq_online = ret; + return 0; +} +subsys_initcall(io_wq_init); diff --git a/fs/io-wq.h b/io_uring/io-wq.h similarity index 81% rename from fs/io-wq.h rename to io_uring/io-wq.h index 75113bcd5889..bf5c4c533760 100644 --- a/fs/io-wq.h +++ b/io_uring/io-wq.h @@ -1,7 +1,7 @@ #ifndef INTERNAL_IO_WQ_H #define INTERNAL_IO_WQ_H

-#include <linux/io_uring.h> +#include <linux/refcount.h>

struct io_wq;

@@ -9,16 +9,8 @@ enum { IO_WQ_WORK_CANCEL = 1, IO_WQ_WORK_HASHED = 2, IO_WQ_WORK_UNBOUND = 4, - IO_WQ_WORK_NO_CANCEL = 8, IO_WQ_WORK_CONCURRENT = 16,

- IO_WQ_WORK_FILES = 32, - IO_WQ_WORK_FS = 64, - IO_WQ_WORK_MM = 128, - IO_WQ_WORK_CREDS = 256, - IO_WQ_WORK_BLKCG = 512, - IO_WQ_WORK_FSIZE = 1024, - IO_WQ_HASH_SHIFT = 24, /* upper 8 bits are used for hash key */ };

@@ -52,6 +44,7 @@ static inline void wq_list_add_after(struct io_wq_work_node *node, static inline void wq_list_add_tail(struct io_wq_work_node *node, struct io_wq_work_list *list) { + node->next = NULL; if (!list->first) { list->last = node; WRITE_ONCE(list->first, node); @@ -59,7 +52,6 @@ static inline void wq_list_add_tail(struct io_wq_work_node *node, list->last->next = node; list->last = node; } - node->next = NULL; }

static inline void wq_list_cut(struct io_wq_work_list *list, @@ -95,7 +87,6 @@ static inline void wq_list_del(struct io_wq_work_list *list,

struct io_wq_work { struct io_wq_work_node list; - struct io_identity *identity; unsigned flags; };

@@ -107,37 +98,48 @@ static inline struct io_wq_work *wq_next_work(struct io_wq_work *work) return container_of(work->list.next, struct io_wq_work, list); }

-typedef void (free_work_fn)(struct io_wq_work *); -typedef struct io_wq_work *(io_wq_work_fn)(struct io_wq_work *); +typedef struct io_wq_work *(free_work_fn)(struct io_wq_work *); +typedef void (io_wq_work_fn)(struct io_wq_work *);

-struct io_wq_data { - struct user_struct *user; +struct io_wq_hash { + refcount_t refs; + unsigned long map; + struct wait_queue_head wait; +}; + +static inline void io_wq_put_hash(struct io_wq_hash *hash) +{ + if (refcount_dec_and_test(&hash->refs)) + kfree(hash); +}

+struct io_wq_data { + struct io_wq_hash *hash; + struct task_struct *task; io_wq_work_fn *do_work; free_work_fn *free_work; };

struct io_wq *io_wq_create(unsigned bounded, struct io_wq_data *data); -bool io_wq_get(struct io_wq *wq, struct io_wq_data *data); -void io_wq_destroy(struct io_wq *wq); +void io_wq_exit_start(struct io_wq *wq); +void io_wq_put_and_exit(struct io_wq *wq);

void io_wq_enqueue(struct io_wq *wq, struct io_wq_work *work); void io_wq_hash_work(struct io_wq_work *work, void *val);

+int io_wq_cpu_affinity(struct io_wq *wq, cpumask_var_t mask); +int io_wq_max_workers(struct io_wq *wq, int *new_count); + static inline bool io_wq_is_hashed(struct io_wq_work *work) { return work->flags & IO_WQ_WORK_HASHED; }

-void io_wq_cancel_all(struct io_wq *wq); - typedef bool (work_cancel_fn)(struct io_wq_work *, void *);

enum io_wq_cancel io_wq_cancel_cb(struct io_wq *wq, work_cancel_fn *cancel, void *data, bool cancel_all);

-struct task_struct *io_wq_get_task(struct io_wq *wq); - #if defined(CONFIG_IO_WQ) extern void io_wq_worker_sleeping(struct task_struct *); extern void io_wq_worker_running(struct task_struct *); @@ -152,6 +154,7 @@ static inline void io_wq_worker_running(struct task_struct *tsk)

static inline bool io_wq_current_is_worker(void) { - return in_task() && (current->flags & PF_IO_WORKER); + return in_task() && (current->flags & PF_IO_WORKER) && + current->pf_io_worker; } #endif diff --git a/fs/io_uring.c b/io_uring/io_uring.c similarity index 51% rename from fs/io_uring.c rename to io_uring/io_uring.c index 1d8173741310..473dbd1830a3 100644 --- a/fs/io_uring.c +++ b/io_uring/io_uring.c @@ -11,7 +11,7 @@ * before writing the tail (using smp_load_acquire to read the tail will * do). It also needs a smp_mb() before updating CQ head (ordering the * entry load(s) with the head store), pairing with an implicit barrier - * through a control-dependency in io_get_cqring (smp_store_release to + * through a control-dependency in io_get_cqe (smp_store_release to * store head will do). Failure to do so could lead to reading invalid * CQ entries. * @@ -57,7 +57,6 @@ #include <linux/mman.h> #include <linux/percpu.h> #include <linux/slab.h> -#include <linux/kthread.h> #include <linux/blkdev.h> #include <linux/bvec.h> #include <linux/net.h> @@ -75,35 +74,43 @@ #include <linux/fsnotify.h> #include <linux/fadvise.h> #include <linux/eventpoll.h> -#include <linux/fs_struct.h> #include <linux/splice.h> #include <linux/task_work.h> #include <linux/pagemap.h> #include <linux/io_uring.h> -#include <linux/blk-cgroup.h> -#include <linux/audit.h> +#include <linux/tracehook.h>

#define CREATE_TRACE_POINTS #include <trace/events/io_uring.h>

#include <uapi/linux/io_uring.h>

-#include "internal.h" +#include "../fs/internal.h" #include "io-wq.h"

#define IORING_MAX_ENTRIES 32768 #define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES) +#define IORING_SQPOLL_CAP_ENTRIES_VALUE 8

-/* - * Shift of 9 is 512 entries, or exactly one page on 64-bit archs - */ -#define IORING_FILE_TABLE_SHIFT 9 -#define IORING_MAX_FILES_TABLE (1U << IORING_FILE_TABLE_SHIFT) -#define IORING_FILE_TABLE_MASK (IORING_MAX_FILES_TABLE - 1) -#define IORING_MAX_FIXED_FILES (64 * IORING_MAX_FILES_TABLE) +/* only define max */ +#define IORING_MAX_FIXED_FILES (1U << 15) #define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \ IORING_REGISTER_LAST + IORING_OP_LAST)

+#define IO_RSRC_TAG_TABLE_SHIFT (PAGE_SHIFT - 3) +#define IO_RSRC_TAG_TABLE_MAX (1U << IO_RSRC_TAG_TABLE_SHIFT) +#define IO_RSRC_TAG_TABLE_MASK (IO_RSRC_TAG_TABLE_MAX - 1) + +#define IORING_MAX_REG_BUFFERS (1U << 14) + +#define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \ + IOSQE_IO_HARDLINK | IOSQE_ASYNC | \ + IOSQE_BUFFER_SELECT) +#define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \ + REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS) + +#define IO_TCTX_REFS_CACHE_NR (1U << 10) + struct io_uring { u32 head ____cacheline_aligned_in_smp; u32 tail ____cacheline_aligned_in_smp; @@ -162,7 +169,7 @@ struct io_rings { * Written by the application, shouldn't be modified by the * kernel. */ - u32 cq_flags; + u32 cq_flags; /* * Number of completion events lost because the queue was full; * this should be avoided by the application by making sure @@ -187,36 +194,64 @@ struct io_rings { struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp; };

+enum io_uring_cmd_flags { + IO_URING_F_NONBLOCK = 1, + IO_URING_F_COMPLETE_DEFER = 2, +}; + struct io_mapped_ubuf { u64 ubuf; - size_t len; - struct bio_vec *bvec; + u64 ubuf_end; unsigned int nr_bvecs; unsigned long acct_pages; + struct bio_vec bvec[]; +}; + +struct io_ring_ctx; + +struct io_overflow_cqe { + struct io_uring_cqe cqe; + struct list_head list; +}; + +struct io_fixed_file { + /* file * with additional FFS_* flags */ + unsigned long file_ptr; +}; + +struct io_rsrc_put { + struct list_head list; + u64 tag; + union { + void *rsrc; + struct file *file; + struct io_mapped_ubuf *buf; + }; };

-struct fixed_file_table { - struct file **files; +struct io_file_table { + struct io_fixed_file *files; };

-struct fixed_file_ref_node { +struct io_rsrc_node { struct percpu_ref refs; struct list_head node; - struct list_head file_list; - struct fixed_file_data *file_data; + struct list_head rsrc_list; + struct io_rsrc_data *rsrc_data; struct llist_node llist; bool done; };

-struct fixed_file_data { - struct fixed_file_table *table; +typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc); + +struct io_rsrc_data { struct io_ring_ctx *ctx;

- struct fixed_file_ref_node *node; - struct percpu_ref refs; + u64 **tags; + unsigned int nr; + rsrc_put_fn *do_put; + atomic_t refs; struct completion done; - struct list_head ref_list; - spinlock_t lock; bool quiesce; };

@@ -235,33 +270,81 @@ struct io_restriction { bool registered; };

+enum { + IO_SQ_THREAD_SHOULD_STOP = 0, + IO_SQ_THREAD_SHOULD_PARK, +}; + struct io_sq_data { refcount_t refs; + atomic_t park_pending; struct mutex lock;

/* ctx's that are using this sqd */ struct list_head ctx_list; - struct list_head ctx_new_list; - struct mutex ctx_lock;

struct task_struct *thread; struct wait_queue_head wait; + + unsigned sq_thread_idle; + int sq_cpu; + pid_t task_pid; + pid_t task_tgid; + + unsigned long state; + struct completion exited; +}; + +#define IO_COMPL_BATCH 32 +#define IO_REQ_CACHE_SIZE 32 +#define IO_REQ_ALLOC_BATCH 8 + +struct io_submit_link { + struct io_kiocb *head; + struct io_kiocb *last; +}; + +struct io_submit_state { + struct blk_plug plug; + struct io_submit_link link; + + /* + * io_kiocb alloc cache + */ + void *reqs[IO_REQ_CACHE_SIZE]; + unsigned int free_reqs; + + bool plug_started; + + /* + * Batch completion logic + */ + struct io_kiocb *compl_reqs[IO_COMPL_BATCH]; + unsigned int compl_nr; + /* inline/task_work completion list, under ->uring_lock */ + struct list_head free_list; + + unsigned int ios_left; };

struct io_ring_ctx { + /* const or read-mostly hot data */ struct { struct percpu_ref refs; - } ____cacheline_aligned_in_smp;

- struct { + struct io_rings *rings; unsigned int flags; unsigned int compat: 1; - unsigned int limit_mem: 1; - unsigned int cq_overflow_flushed: 1; unsigned int drain_next: 1; unsigned int eventfd_async: 1; unsigned int restricted: 1; - unsigned int sqo_dead: 1; + unsigned int off_timeout_used: 1; + unsigned int drain_active: 1; + } ____cacheline_aligned_in_smp; + + /* submission data */ + struct { + struct mutex uring_lock;

/* * Ring buffer of indices into array of io_uring_sqe, which is @@ -275,101 +358,59 @@ struct io_ring_ctx { * array. */ u32 *sq_array; + struct io_uring_sqe *sq_sqes; unsigned cached_sq_head; unsigned sq_entries; - unsigned sq_mask; - unsigned sq_thread_idle; - unsigned cached_sq_dropped; - unsigned cached_cq_overflow; - unsigned long sq_check_overflow; - struct list_head defer_list; + + /* + * Fixed resources fast path, should be accessed only under + * uring_lock, and updated through io_uring_register(2) + */ + struct io_rsrc_node *rsrc_node; + struct io_file_table file_table; + unsigned nr_user_files; + unsigned nr_user_bufs; + struct io_mapped_ubuf **user_bufs; + + struct io_submit_state submit_state; struct list_head timeout_list; + struct list_head ltimeout_list; struct list_head cq_overflow_list; - - struct io_uring_sqe *sq_sqes; + struct xarray io_buffers; + struct xarray personalities; + u32 pers_next; + unsigned sq_thread_idle; } ____cacheline_aligned_in_smp;

- struct io_rings *rings; - - /* IO offload */ - struct io_wq *io_wq; - - /* - * For SQPOLL usage - we hold a reference to the parent task, so we - * have access to the ->files - */ - struct task_struct *sqo_task; - - /* Only used for accounting purposes */ - struct mm_struct *mm_account; - -#ifdef CONFIG_BLK_CGROUP - struct cgroup_subsys_state *sqo_blkcg_css; -#endif + /* IRQ completion list, under ->completion_lock */ + struct list_head locked_free_list; + unsigned int locked_free_nr;

+ const struct cred *sq_creds; /* cred used for __io_sq_thread() */ struct io_sq_data *sq_data; /* if using sq thread polling */

struct wait_queue_head sqo_sq_wait; - struct wait_queue_entry sqo_wait_entry; struct list_head sqd_list;

- /* - * If used, fixed file set. Writers must ensure that ->refs is dead, - * readers must ensure that ->refs is alive as long as the file* is - * used. Only updated through io_uring_register(2). - */ - struct fixed_file_data *file_data; - unsigned nr_user_files; - - /* if used, fixed mapped user buffers */ - unsigned nr_user_bufs; - struct io_mapped_ubuf *user_bufs; - - struct user_struct *user; - - const struct cred *creds; - -#ifdef CONFIG_AUDIT - kuid_t loginuid; - unsigned int sessionid; -#endif - - struct completion ref_comp; - struct completion sq_thread_comp; - - /* if all else fails... */ - struct io_kiocb *fallback_req; - -#if defined(CONFIG_UNIX) - struct socket *ring_sock; -#endif - - struct xarray io_buffers; - - struct xarray personalities; - u32 pers_next; + unsigned long check_cq_overflow;

struct { unsigned cached_cq_tail; unsigned cq_entries; - unsigned cq_mask; + struct eventfd_ctx *cq_ev_fd; + struct wait_queue_head poll_wait; + struct wait_queue_head cq_wait; + unsigned cq_extra; atomic_t cq_timeouts; unsigned cq_last_tm_flush; - unsigned long cq_check_overflow; - struct wait_queue_head cq_wait; - struct fasync_struct *cq_fasync; - struct eventfd_ctx *cq_ev_fd; - } ____cacheline_aligned_in_smp; - - struct { - struct mutex uring_lock; - wait_queue_head_t wait; } ____cacheline_aligned_in_smp;

struct { spinlock_t completion_lock;

+ spinlock_t timeout_lock; + /* * ->iopoll_list is protected by the ctx->uring_lock for * io_uring instances that don't use IORING_SETUP_SQPOLL. @@ -379,17 +420,62 @@ struct io_ring_ctx { struct list_head iopoll_list; struct hlist_head *cancel_hash; unsigned cancel_hash_bits; - bool poll_multi_file; - - spinlock_t inflight_lock; - struct list_head inflight_list; + bool poll_multi_queue; } ____cacheline_aligned_in_smp;

- struct delayed_work file_put_work; - struct llist_head file_put_llist; - - struct work_struct exit_work; struct io_restriction restrictions; + + /* slow path rsrc auxilary data, used by update/register */ + struct { + struct io_rsrc_node *rsrc_backup_node; + struct io_mapped_ubuf *dummy_ubuf; + struct io_rsrc_data *file_data; + struct io_rsrc_data *buf_data; + + struct delayed_work rsrc_put_work; + struct llist_head rsrc_put_llist; + struct list_head rsrc_ref_list; + spinlock_t rsrc_ref_lock; + }; + + /* Keep this last, we don't need it for the fast path */ + struct { + #if defined(CONFIG_UNIX) + struct socket *ring_sock; + #endif + /* hashed buffered write serialization */ + struct io_wq_hash *hash_map; + + /* Only used for accounting purposes */ + struct user_struct *user; + struct mm_struct *mm_account; + + /* ctx exit and cancelation */ + struct llist_head fallback_llist; + struct delayed_work fallback_work; + struct work_struct exit_work; + struct list_head tctx_list; + struct completion ref_comp; + u32 iowq_limits[2]; + bool iowq_limits_set; + }; +}; + +struct io_uring_task { + /* submission side */ + int cached_refs; + struct xarray xa; + struct wait_queue_head wait; + const struct io_ring_ctx *last; + struct io_wq *io_wq; + struct percpu_counter inflight; + atomic_t inflight_tracked; + atomic_t in_idle; + + spinlock_t task_lock; + struct io_wq_work_list task_list; + struct callback_head task_work; + bool task_running; };

/* @@ -398,20 +484,24 @@ struct io_ring_ctx { */ struct io_poll_iocb { struct file *file; - union { - struct wait_queue_head *head; - u64 addr; - }; + struct wait_queue_head *head; __poll_t events; - bool done; - bool canceled; struct wait_queue_entry wait; };

+struct io_poll_update { + struct file *file; + u64 old_user_data; + u64 new_user_data; + __poll_t events; + bool update_events; + bool update_user_data; +}; + struct io_close { struct file *file; - struct file *put_file; int fd; + u32 file_slot; };

struct io_timeout_data { @@ -419,6 +509,7 @@ struct io_timeout_data { struct hrtimer timer; struct timespec64 ts; enum hrtimer_mode mode; + u32 flags; };

struct io_accept { @@ -426,6 +517,7 @@ struct io_accept { struct sockaddr __user *addr; int __user *addr_len; int flags; + u32 file_slot; unsigned long nofile; };

@@ -447,11 +539,20 @@ struct io_timeout { u32 off; u32 target_seq; struct list_head list; + /* head of the link, used by linked timeouts only */ + struct io_kiocb *head; + /* for linked completions */ + struct io_kiocb *prev; };

struct io_timeout_rem { struct file *file; u64 addr; + + /* timeout update */ + struct timespec64 ts; + u32 flags; + bool ltimeout; };

struct io_rw { @@ -470,8 +571,9 @@ struct io_connect { struct io_sr_msg { struct file *file; union { - struct user_msghdr __user *umsg; - void __user *buf; + struct compat_msghdr __user *umsg_compat; + struct user_msghdr __user *umsg; + void __user *buf; }; int msg_flags; int bgid; @@ -482,13 +584,13 @@ struct io_sr_msg { struct io_open { struct file *file; int dfd; - bool ignore_nonblock; + u32 file_slot; struct filename *filename; struct open_how how; unsigned long nofile; };

-struct io_files_update { +struct io_rsrc_update { struct file *file; u64 arg; u32 nr_args; @@ -519,10 +621,10 @@ struct io_epoll {

struct io_splice { struct file *file_out; - struct file *file_in; loff_t off_out; loff_t off_in; u64 len; + int splice_fd_in; unsigned int flags; };

@@ -544,9 +646,52 @@ struct io_statx { struct statx __user *buffer; };

+struct io_shutdown { + struct file *file; + int how; +}; + +struct io_rename { + struct file *file; + int old_dfd; + int new_dfd; + struct filename *oldpath; + struct filename *newpath; + int flags; +}; + +struct io_unlink { + struct file *file; + int dfd; + int flags; + struct filename *filename; +}; + +struct io_mkdir { + struct file *file; + int dfd; + umode_t mode; + struct filename *filename; +}; + +struct io_symlink { + struct file *file; + int new_dfd; + struct filename *oldpath; + struct filename *newpath; +}; + +struct io_hardlink { + struct file *file; + int old_dfd; + int new_dfd; + struct filename *oldpath; + struct filename *newpath; + int flags; +}; + struct io_completion { struct file *file; - struct list_head list; u32 cflags; };

@@ -556,7 +701,8 @@ struct io_async_connect {

struct io_async_msghdr { struct iovec fast_iov[UIO_FASTIOV]; - struct iovec *iov; + /* points to an allocated iov, if NULL we use fast_iov instead */ + struct iovec *free_iov; struct sockaddr __user *uaddr; struct msghdr msg; struct sockaddr_storage addr; @@ -566,6 +712,7 @@ struct io_async_rw { struct iovec fast_iov[UIO_FASTIOV]; const struct iovec *free_iovec; struct iov_iter iter; + struct iov_iter_state iter_state; size_t bytes_done; struct wait_page_queue wpq; }; @@ -578,19 +725,24 @@ enum { REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT, REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,

- REQ_F_LINK_HEAD_BIT, - REQ_F_FAIL_LINK_BIT, + /* first byte is taken by user flags, shift it to not overlap */ + REQ_F_FAIL_BIT = 8, REQ_F_INFLIGHT_BIT, REQ_F_CUR_POS_BIT, REQ_F_NOWAIT_BIT, REQ_F_LINK_TIMEOUT_BIT, - REQ_F_ISREG_BIT, REQ_F_NEED_CLEANUP_BIT, REQ_F_POLLED_BIT, REQ_F_BUFFER_SELECTED_BIT, - REQ_F_NO_FILE_TABLE_BIT, - REQ_F_WORK_INITIALIZED_BIT, - REQ_F_LTIMEOUT_ACTIVE_BIT, + REQ_F_COMPLETE_INLINE_BIT, + REQ_F_REISSUE_BIT, + REQ_F_CREDS_BIT, + REQ_F_REFCOUNT_BIT, + REQ_F_ARM_LTIMEOUT_BIT, + /* keep async read/write and isreg together and in order */ + REQ_F_NOWAIT_READ_BIT, + REQ_F_NOWAIT_WRITE_BIT, + REQ_F_ISREG_BIT,

/* not a real bit, just to check we're not overflowing the space */ __REQ_F_LAST_BIT, @@ -610,11 +762,9 @@ enum { /* IOSQE_BUFFER_SELECT */ REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),

- /* head of a link */ - REQ_F_LINK_HEAD = BIT(REQ_F_LINK_HEAD_BIT), /* fail rest of links */ - REQ_F_FAIL_LINK = BIT(REQ_F_FAIL_LINK_BIT), - /* on inflight list */ + REQ_F_FAIL = BIT(REQ_F_FAIL_BIT), + /* on inflight list, should be cancelled and waited on exit reliably */ REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT), /* read/write uses file position */ REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT), @@ -622,20 +772,28 @@ enum { REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT), /* has or had linked timeout */ REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT), - /* regular file */ - REQ_F_ISREG = BIT(REQ_F_ISREG_BIT), /* needs cleanup */ REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT), /* already went through poll handler */ REQ_F_POLLED = BIT(REQ_F_POLLED_BIT), /* buffer already selected */ REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT), - /* doesn't need file table for this request */ - REQ_F_NO_FILE_TABLE = BIT(REQ_F_NO_FILE_TABLE_BIT), - /* io_wq_work is initialized */ - REQ_F_WORK_INITIALIZED = BIT(REQ_F_WORK_INITIALIZED_BIT), - /* linked timeout is active, i.e. prepared by link's head */ - REQ_F_LTIMEOUT_ACTIVE = BIT(REQ_F_LTIMEOUT_ACTIVE_BIT), + /* completion is deferred through io_comp_state */ + REQ_F_COMPLETE_INLINE = BIT(REQ_F_COMPLETE_INLINE_BIT), + /* caller should reissue async */ + REQ_F_REISSUE = BIT(REQ_F_REISSUE_BIT), + /* supports async reads */ + REQ_F_NOWAIT_READ = BIT(REQ_F_NOWAIT_READ_BIT), + /* supports async writes */ + REQ_F_NOWAIT_WRITE = BIT(REQ_F_NOWAIT_WRITE_BIT), + /* regular file */ + REQ_F_ISREG = BIT(REQ_F_ISREG_BIT), + /* has creds assigned */ + REQ_F_CREDS = BIT(REQ_F_CREDS_BIT), + /* skip refcounting if not set */ + REQ_F_REFCOUNT = BIT(REQ_F_REFCOUNT_BIT), + /* there is a linked timeout that has to be armed */ + REQ_F_ARM_LTIMEOUT = BIT(REQ_F_ARM_LTIMEOUT_BIT), };

struct async_poll { @@ -643,6 +801,21 @@ struct async_poll { struct io_poll_iocb *double_poll; };

+typedef void (*io_req_tw_func_t)(struct io_kiocb *req, bool *locked); + +struct io_task_work { + union { + struct io_wq_work_node node; + struct llist_node fallback_node; + }; + io_req_tw_func_t func; +}; + +enum { + IORING_RSRC_FILE = 0, + IORING_RSRC_BUFFER = 1, +}; + /* * NOTE! Each of the iocb union members has the file pointer * as the first entry in their struct definition. So you can @@ -654,6 +827,7 @@ struct io_kiocb { struct file *file; struct io_rw rw; struct io_poll_iocb poll; + struct io_poll_update poll_update; struct io_accept accept; struct io_sync sync; struct io_cancel cancel; @@ -663,13 +837,19 @@ struct io_kiocb { struct io_sr_msg sr_msg; struct io_open open; struct io_close close; - struct io_files_update files_update; + struct io_rsrc_update rsrc_update; struct io_fadvise fadvise; struct io_madvise madvise; struct io_epoll epoll; struct io_splice splice; struct io_provide_buf pbuf; struct io_statx statx; + struct io_shutdown shutdown; + struct io_rename rename; + struct io_unlink unlink; + struct io_mkdir mkdir; + struct io_symlink symlink; + struct io_hardlink hardlink; /* use only after cleaning per-op data, see io_clean_op() */ struct io_completion compl; }; @@ -685,70 +865,44 @@ struct io_kiocb {

struct io_ring_ctx *ctx; unsigned int flags; - refcount_t refs; + atomic_t refs; struct task_struct *task; u64 user_data;

- struct list_head link_list; + struct io_kiocb *link; + struct percpu_ref *fixed_rsrc_refs;

- /* - * 1. used with ctx->iopoll_list with reads/writes - * 2. to track reqs with ->files (see io_op_def::file_table) - */ + /* used with ctx->iopoll_list with reads/writes */ struct list_head inflight_entry; - - struct list_head iopoll_entry; - - struct percpu_ref *fixed_file_refs; - struct callback_head task_work; + struct io_task_work io_task_work; /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */ struct hlist_node hash_node; struct async_poll *apoll; struct io_wq_work work; -}; + const struct cred *creds;

-struct io_defer_entry { - struct list_head list; - struct io_kiocb *req; - u32 seq; + /* store used ubuf, so we can prevent reloading */ + struct io_mapped_ubuf *imu; + /* stores selected buf, valid IFF REQ_F_BUFFER_SELECTED is set */ + struct io_buffer *kbuf; + atomic_t poll_refs; };

-#define IO_IOPOLL_BATCH 8 - -struct io_comp_state { - unsigned int nr; - struct list_head list; +struct io_tctx_node { + struct list_head ctx_node; + struct task_struct *task; struct io_ring_ctx *ctx; };

-struct io_submit_state { - struct blk_plug plug; - - /* - * io_kiocb alloc cache - */ - void *reqs[IO_IOPOLL_BATCH]; - unsigned int free_reqs; - - /* - * Batch completion logic - */ - struct io_comp_state comp; - - /* - * File reference cache - */ - struct file *file; - unsigned int fd; - unsigned int has_refs; - unsigned int ios_left; +struct io_defer_entry { + struct list_head list; + struct io_kiocb *req; + u32 seq; };

struct io_op_def { /* needs req->file assigned */ unsigned needs_file : 1; - /* don't fail if file grab fails */ - unsigned needs_file_no_error : 1; /* hash wq insertion if file is a regular file */ unsigned hash_reg_file : 1; /* unbound wq insertion if file is a non-regular file */ @@ -760,11 +914,12 @@ struct io_op_def { unsigned pollout : 1; /* op supports buffer selection */ unsigned buffer_select : 1; - /* must always have async data allocated */ - unsigned needs_async_data : 1; + /* do prep async if is going to be punted */ + unsigned needs_async_setup : 1; + /* should block plug */ + unsigned plug : 1; /* size of async data needed, if any */ unsigned short async_size; - unsigned work_flags; };

static const struct io_op_def io_op_defs[] = { @@ -774,41 +929,36 @@ static const struct io_op_def io_op_defs[] = { .unbound_nonreg_file = 1, .pollin = 1, .buffer_select = 1, - .needs_async_data = 1, + .needs_async_setup = 1, + .plug = 1, .async_size = sizeof(struct io_async_rw), - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG | - IO_WQ_WORK_FILES, }, [IORING_OP_WRITEV] = { .needs_file = 1, .hash_reg_file = 1, .unbound_nonreg_file = 1, .pollout = 1, - .needs_async_data = 1, + .needs_async_setup = 1, + .plug = 1, .async_size = sizeof(struct io_async_rw), - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG | - IO_WQ_WORK_FSIZE | IO_WQ_WORK_FILES, }, [IORING_OP_FSYNC] = { .needs_file = 1, - .work_flags = IO_WQ_WORK_BLKCG, }, [IORING_OP_READ_FIXED] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollin = 1, + .plug = 1, .async_size = sizeof(struct io_async_rw), - .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_MM | - IO_WQ_WORK_FILES, }, [IORING_OP_WRITE_FIXED] = { .needs_file = 1, .hash_reg_file = 1, .unbound_nonreg_file = 1, .pollout = 1, + .plug = 1, .async_size = sizeof(struct io_async_rw), - .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_FSIZE | - IO_WQ_WORK_MM | IO_WQ_WORK_FILES, }, [IORING_OP_POLL_ADD] = { .needs_file = 1, @@ -817,126 +967,91 @@ static const struct io_op_def io_op_defs[] = { [IORING_OP_POLL_REMOVE] = {}, [IORING_OP_SYNC_FILE_RANGE] = { .needs_file = 1, - .work_flags = IO_WQ_WORK_BLKCG, }, [IORING_OP_SENDMSG] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollout = 1, - .needs_async_data = 1, + .needs_async_setup = 1, .async_size = sizeof(struct io_async_msghdr), - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG | - IO_WQ_WORK_FS, }, [IORING_OP_RECVMSG] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollin = 1, .buffer_select = 1, - .needs_async_data = 1, + .needs_async_setup = 1, .async_size = sizeof(struct io_async_msghdr), - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG | - IO_WQ_WORK_FS, }, [IORING_OP_TIMEOUT] = { - .needs_async_data = 1, .async_size = sizeof(struct io_timeout_data), - .work_flags = IO_WQ_WORK_MM, }, - [IORING_OP_TIMEOUT_REMOVE] = {}, + [IORING_OP_TIMEOUT_REMOVE] = { + /* used by timeout updates' prep() */ + }, [IORING_OP_ACCEPT] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollin = 1, - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_FILES, }, [IORING_OP_ASYNC_CANCEL] = {}, [IORING_OP_LINK_TIMEOUT] = { - .needs_async_data = 1, .async_size = sizeof(struct io_timeout_data), - .work_flags = IO_WQ_WORK_MM, }, [IORING_OP_CONNECT] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollout = 1, - .needs_async_data = 1, + .needs_async_setup = 1, .async_size = sizeof(struct io_async_connect), - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_FS, }, [IORING_OP_FALLOCATE] = { .needs_file = 1, - .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_FSIZE, - }, - [IORING_OP_OPENAT] = { - .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_BLKCG | - IO_WQ_WORK_FS, - }, - [IORING_OP_CLOSE] = { - .needs_file = 1, - .needs_file_no_error = 1, - .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_BLKCG, - }, - [IORING_OP_FILES_UPDATE] = { - .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_MM, - }, - [IORING_OP_STATX] = { - .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_MM | - IO_WQ_WORK_FS | IO_WQ_WORK_BLKCG, }, + [IORING_OP_OPENAT] = {}, + [IORING_OP_CLOSE] = {}, + [IORING_OP_FILES_UPDATE] = {}, + [IORING_OP_STATX] = {}, [IORING_OP_READ] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollin = 1, .buffer_select = 1, + .plug = 1, .async_size = sizeof(struct io_async_rw), - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG | - IO_WQ_WORK_FILES, }, [IORING_OP_WRITE] = { .needs_file = 1, .hash_reg_file = 1, .unbound_nonreg_file = 1, .pollout = 1, + .plug = 1, .async_size = sizeof(struct io_async_rw), - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG | - IO_WQ_WORK_FSIZE | IO_WQ_WORK_FILES, }, [IORING_OP_FADVISE] = { .needs_file = 1, - .work_flags = IO_WQ_WORK_BLKCG, - }, - [IORING_OP_MADVISE] = { - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG, }, + [IORING_OP_MADVISE] = {}, [IORING_OP_SEND] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollout = 1, - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG | - IO_WQ_WORK_FS, }, [IORING_OP_RECV] = { .needs_file = 1, .unbound_nonreg_file = 1, .pollin = 1, .buffer_select = 1, - .work_flags = IO_WQ_WORK_MM | IO_WQ_WORK_BLKCG | - IO_WQ_WORK_FS, }, [IORING_OP_OPENAT2] = { - .work_flags = IO_WQ_WORK_FILES | IO_WQ_WORK_FS | - IO_WQ_WORK_BLKCG, }, [IORING_OP_EPOLL_CTL] = { .unbound_nonreg_file = 1, - .work_flags = IO_WQ_WORK_FILES, }, [IORING_OP_SPLICE] = { .needs_file = 1, .hash_reg_file = 1, .unbound_nonreg_file = 1, - .work_flags = IO_WQ_WORK_BLKCG | IO_WQ_WORK_FILES, }, [IORING_OP_PROVIDE_BUFFERS] = {}, [IORING_OP_REMOVE_BUFFERS] = {}, @@ -945,43 +1060,47 @@ static const struct io_op_def io_op_defs[] = { .hash_reg_file = 1, .unbound_nonreg_file = 1, }, + [IORING_OP_SHUTDOWN] = { + .needs_file = 1, + }, + [IORING_OP_RENAMEAT] = {}, + [IORING_OP_UNLINKAT] = {}, };

-enum io_mem_account { - ACCT_LOCKED, - ACCT_PINNED, -}; +/* requests with any of those set should undergo io_disarm_next() */ +#define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)

-static void destroy_fixed_file_ref_node(struct fixed_file_ref_node *ref_node); -static struct fixed_file_ref_node *alloc_fixed_file_ref_node( - struct io_ring_ctx *ctx); +static bool io_disarm_next(struct io_kiocb *req); +static void io_uring_del_tctx_node(unsigned long index); +static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx, + struct task_struct *task, + bool cancel_all); +static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd); + +static void io_fill_cqe_req(struct io_kiocb *req, s32 res, u32 cflags);

-static void __io_complete_rw(struct io_kiocb *req, long res, long res2, - struct io_comp_state *cs); -static void io_cqring_fill_event(struct io_kiocb *req, long res); static void io_put_req(struct io_kiocb *req); -static void io_put_req_deferred(struct io_kiocb *req, int nr); -static void io_double_put_req(struct io_kiocb *req); -static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req); -static void __io_queue_linked_timeout(struct io_kiocb *req); +static void io_put_req_deferred(struct io_kiocb *req); +static void io_dismantle_req(struct io_kiocb *req); static void io_queue_linked_timeout(struct io_kiocb *req); -static int __io_sqe_files_update(struct io_ring_ctx *ctx, - struct io_uring_files_update *ip, - unsigned nr_args); -static void __io_clean_op(struct io_kiocb *req); -static struct file *io_file_get(struct io_submit_state *state, +static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type, + struct io_uring_rsrc_update2 *up, + unsigned nr_args); +static void io_clean_op(struct io_kiocb *req); +static struct file *io_file_get(struct io_ring_ctx *ctx, struct io_kiocb *req, int fd, bool fixed); -static void __io_queue_sqe(struct io_kiocb *req, struct io_comp_state *cs); -static void io_file_put_work(struct work_struct *work); +static void __io_queue_sqe(struct io_kiocb *req); +static void io_rsrc_put_work(struct work_struct *work);

-static ssize_t io_import_iovec(int rw, struct io_kiocb *req, - struct iovec **iovec, struct iov_iter *iter, - bool needs_lock); -static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec, - const struct iovec *fast_iov, - struct iov_iter *iter, bool force); -static void io_req_drop_files(struct io_kiocb *req); static void io_req_task_queue(struct io_kiocb *req); +static void io_submit_flush_completions(struct io_ring_ctx *ctx); +static int io_req_prep_async(struct io_kiocb *req); + +static int io_install_fixed_file(struct io_kiocb *req, struct file *file, + unsigned int issue_flags, u32 slot_index); +static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags); + +static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer);

static struct kmem_cache *req_cachep;

@@ -1000,21 +1119,67 @@ struct sock *io_uring_get_socket(struct file *file) } EXPORT_SYMBOL(io_uring_get_socket);

-static inline void io_clean_op(struct io_kiocb *req) +static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked) +{ + if (!*locked) { + mutex_lock(&ctx->uring_lock); + *locked = true; + } +} + +#define io_for_each_link(pos, head) \ + for (pos = (head); pos; pos = pos->link) + +/* + * Shamelessly stolen from the mm implementation of page reference checking, + * see commit f958d7b528b1 for details. + */ +#define req_ref_zero_or_close_to_overflow(req) \ + ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u) + +static inline bool req_ref_inc_not_zero(struct io_kiocb *req) { - if (req->flags & (REQ_F_NEED_CLEANUP | REQ_F_BUFFER_SELECTED)) - __io_clean_op(req); + WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT)); + return atomic_inc_not_zero(&req->refs); }

-static inline bool __io_match_files(struct io_kiocb *req, - struct files_struct *files) +static inline bool req_ref_put_and_test(struct io_kiocb *req) { - if (req->file && req->file->f_op == &io_uring_fops) + if (likely(!(req->flags & REQ_F_REFCOUNT))) return true;

- return ((req->flags & REQ_F_WORK_INITIALIZED) && - (req->work.flags & IO_WQ_WORK_FILES)) && - req->work.identity->files == files; + WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req)); + return atomic_dec_and_test(&req->refs); +} + +static inline void req_ref_get(struct io_kiocb *req) +{ + WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT)); + WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req)); + atomic_inc(&req->refs); +} + +static inline void __io_req_set_refcount(struct io_kiocb *req, int nr) +{ + if (!(req->flags & REQ_F_REFCOUNT)) { + req->flags |= REQ_F_REFCOUNT; + atomic_set(&req->refs, nr); + } +} + +static inline void io_req_set_refcount(struct io_kiocb *req) +{ + __io_req_set_refcount(req, 1); +} + +static inline void io_req_set_rsrc_node(struct io_kiocb *req) +{ + struct io_ring_ctx *ctx = req->ctx; + + if (!req->fixed_rsrc_refs) { + req->fixed_rsrc_refs = &ctx->rsrc_node->refs; + percpu_ref_get(req->fixed_rsrc_refs); + } }

static void io_refs_resurrect(struct percpu_ref *ref, struct completion *compl) @@ -1029,169 +1194,104 @@ static void io_refs_resurrect(struct percpu_ref *ref, struct completion *compl) percpu_ref_put(ref); }

-static bool io_match_task(struct io_kiocb *head, - struct task_struct *task, - struct files_struct *files) +static bool io_match_task(struct io_kiocb *head, struct task_struct *task, + bool cancel_all) + __must_hold(&req->ctx->timeout_lock) { - struct io_kiocb *link; + struct io_kiocb *req;

- if (task && head->task != task) { - /* in terms of cancelation, always match if req task is dead */ - if (head->task->flags & PF_EXITING) - return true; + if (task && head->task != task) return false; - } - if (!files) - return true; - if (__io_match_files(head, files)) + if (cancel_all) return true; - if (head->flags & REQ_F_LINK_HEAD) { - list_for_each_entry(link, &head->link_list, link_list) { - if (__io_match_files(link, files)) - return true; - } + + io_for_each_link(req, head) { + if (req->flags & REQ_F_INFLIGHT) + return true; } return false; }

- -static void io_sq_thread_drop_mm(void) +static bool io_match_linked(struct io_kiocb *head) { - struct mm_struct *mm = current->mm; + struct io_kiocb *req;

- if (mm) { - kthread_unuse_mm(mm); - mmput(mm); - current->mm = NULL; + io_for_each_link(req, head) { + if (req->flags & REQ_F_INFLIGHT) + return true; } + return false; }

-static int __io_sq_thread_acquire_mm(struct io_ring_ctx *ctx) +/* + * As io_match_task() but protected against racing with linked timeouts. + * User must not hold timeout_lock. + */ +static bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task, + bool cancel_all) { - struct mm_struct *mm; - - if (current->flags & PF_EXITING) - return -EFAULT; - if (current->mm) - return 0; + bool matched;

- /* Should never happen */ - if (unlikely(!(ctx->flags & IORING_SETUP_SQPOLL))) - return -EFAULT; + if (task && head->task != task) + return false; + if (cancel_all) + return true;

- task_lock(ctx->sqo_task); - mm = ctx->sqo_task->mm; - if (unlikely(!mm || !mmget_not_zero(mm))) - mm = NULL; - task_unlock(ctx->sqo_task); + if (head->flags & REQ_F_LINK_TIMEOUT) { + struct io_ring_ctx *ctx = head->ctx;

- if (mm) { - kthread_use_mm(mm); - return 0; + /* protect against races with linked timeouts */ + spin_lock_irq(&ctx->timeout_lock); + matched = io_match_linked(head); + spin_unlock_irq(&ctx->timeout_lock); + } else { + matched = io_match_linked(head); } + return matched; +}

- return -EFAULT; -} - -static int io_sq_thread_acquire_mm(struct io_ring_ctx *ctx, - struct io_kiocb *req) -{ - if (!(io_op_defs[req->opcode].work_flags & IO_WQ_WORK_MM)) - return 0; - return __io_sq_thread_acquire_mm(ctx); -} - -static void io_sq_thread_associate_blkcg(struct io_ring_ctx *ctx, - struct cgroup_subsys_state **cur_css) - +static inline void req_set_fail(struct io_kiocb *req) { -#ifdef CONFIG_BLK_CGROUP - /* puts the old one when swapping */ - if (*cur_css != ctx->sqo_blkcg_css) { - kthread_associate_blkcg(ctx->sqo_blkcg_css); - *cur_css = ctx->sqo_blkcg_css; - } -#endif -} - -static void io_sq_thread_unassociate_blkcg(void) -{ -#ifdef CONFIG_BLK_CGROUP - kthread_associate_blkcg(NULL); -#endif + req->flags |= REQ_F_FAIL; }

-static inline void req_set_fail_links(struct io_kiocb *req) +static inline void req_fail_link_node(struct io_kiocb *req, int res) { - if ((req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) == REQ_F_LINK) - req->flags |= REQ_F_FAIL_LINK; + req_set_fail(req); + req->result = res; }

-/* - * None of these are dereferenced, they are simply used to check if any of - * them have changed. If we're under current and check they are still the - * same, we're fine to grab references to them for actual out-of-line use. - */ -static void io_init_identity(struct io_identity *id) +static void io_ring_ctx_ref_free(struct percpu_ref *ref) { - id->files = current->files; - id->mm = current->mm; -#ifdef CONFIG_BLK_CGROUP - rcu_read_lock(); - id->blkcg_css = blkcg_css(); - rcu_read_unlock(); -#endif - id->creds = current_cred(); - id->nsproxy = current->nsproxy; - id->fs = current->fs; - id->fsize = rlimit(RLIMIT_FSIZE); -#ifdef CONFIG_AUDIT - id->loginuid = current->loginuid; - id->sessionid = current->sessionid; -#endif - refcount_set(&id->count, 1); -} + struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);

-static inline void __io_req_init_async(struct io_kiocb *req) -{ - memset(&req->work, 0, sizeof(req->work)); - req->flags |= REQ_F_WORK_INITIALIZED; + complete(&ctx->ref_comp); }

-/* - * Note: must call io_req_init_async() for the first time you - * touch any members of io_wq_work. - */ -static inline void io_req_init_async(struct io_kiocb *req) +static inline bool io_is_timeout_noseq(struct io_kiocb *req) { - struct io_uring_task *tctx = req->task->io_uring; - - if (req->flags & REQ_F_WORK_INITIALIZED) - return; - - __io_req_init_async(req); - - /* Grab a ref if this isn't our static identity */ - req->work.identity = tctx->identity; - if (tctx->identity != &tctx->__identity) - refcount_inc(&req->work.identity->count); + return !req->timeout.off; }

-static inline bool io_async_submit(struct io_ring_ctx *ctx) +static void io_fallback_req_func(struct work_struct *work) { - return ctx->flags & IORING_SETUP_SQPOLL; -} + struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, + fallback_work.work); + struct llist_node *node = llist_del_all(&ctx->fallback_llist); + struct io_kiocb *req, *tmp; + bool locked = false;

-static void io_ring_ctx_ref_free(struct percpu_ref *ref) -{ - struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs); + percpu_ref_get(&ctx->refs); + llist_for_each_entry_safe(req, tmp, node, io_task_work.fallback_node) + req->io_task_work.func(req, &locked);

- complete(&ctx->ref_comp); -} + if (locked) { + if (ctx->submit_state.compl_nr) + io_submit_flush_completions(ctx); + mutex_unlock(&ctx->uring_lock); + } + percpu_ref_put(&ctx->refs);

-static inline bool io_is_timeout_noseq(struct io_kiocb *req) -{ - return !req->timeout.off; }

static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) @@ -1203,10 +1303,6 @@ static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) if (!ctx) return NULL;

- ctx->fallback_req = kmem_cache_alloc(req_cachep, GFP_KERNEL); - if (!ctx->fallback_req) - goto err; - /* * Use 5 bits less than the max cq entries, that should give us around * 32 entries per hash list if totally full and uniformly spread. @@ -1222,6 +1318,12 @@ static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) goto err; __hash_init(ctx->cancel_hash, 1U << hash_bits);

+ ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL); + if (!ctx->dummy_ubuf) + goto err; + /* set invalid range, so io_import_fixed() fails meeting it */ + ctx->dummy_ubuf->ubuf = -1UL; + if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free, PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) goto err; @@ -1229,232 +1331,109 @@ static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) ctx->flags = p->flags; init_waitqueue_head(&ctx->sqo_sq_wait); INIT_LIST_HEAD(&ctx->sqd_list); - init_waitqueue_head(&ctx->cq_wait); + init_waitqueue_head(&ctx->poll_wait); INIT_LIST_HEAD(&ctx->cq_overflow_list); init_completion(&ctx->ref_comp); - init_completion(&ctx->sq_thread_comp); xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1); xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1); mutex_init(&ctx->uring_lock); - init_waitqueue_head(&ctx->wait); + init_waitqueue_head(&ctx->cq_wait); spin_lock_init(&ctx->completion_lock); + spin_lock_init(&ctx->timeout_lock); INIT_LIST_HEAD(&ctx->iopoll_list); INIT_LIST_HEAD(&ctx->defer_list); INIT_LIST_HEAD(&ctx->timeout_list); - spin_lock_init(&ctx->inflight_lock); - INIT_LIST_HEAD(&ctx->inflight_list); - INIT_DELAYED_WORK(&ctx->file_put_work, io_file_put_work); - init_llist_head(&ctx->file_put_llist); + INIT_LIST_HEAD(&ctx->ltimeout_list); + spin_lock_init(&ctx->rsrc_ref_lock); + INIT_LIST_HEAD(&ctx->rsrc_ref_list); + INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work); + init_llist_head(&ctx->rsrc_put_llist); + INIT_LIST_HEAD(&ctx->tctx_list); + INIT_LIST_HEAD(&ctx->submit_state.free_list); + INIT_LIST_HEAD(&ctx->locked_free_list); + INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func); return ctx; err: - if (ctx->fallback_req) - kmem_cache_free(req_cachep, ctx->fallback_req); + kfree(ctx->dummy_ubuf); kfree(ctx->cancel_hash); kfree(ctx); return NULL; }

+static void io_account_cq_overflow(struct io_ring_ctx *ctx) +{ + struct io_rings *r = ctx->rings; + + WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1); + ctx->cq_extra--; +} + static bool req_need_defer(struct io_kiocb *req, u32 seq) { if (unlikely(req->flags & REQ_F_IO_DRAIN)) { struct io_ring_ctx *ctx = req->ctx;

- return seq != ctx->cached_cq_tail - + READ_ONCE(ctx->cached_cq_overflow); + return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail; }

return false; }

-static void __io_commit_cqring(struct io_ring_ctx *ctx) -{ - struct io_rings *rings = ctx->rings; - - /* order cqe stores with ring update */ - smp_store_release(&rings->cq.tail, ctx->cached_cq_tail); -} +#define FFS_ASYNC_READ 0x1UL +#define FFS_ASYNC_WRITE 0x2UL +#ifdef CONFIG_64BIT +#define FFS_ISREG 0x4UL +#else +#define FFS_ISREG 0x0UL +#endif +#define FFS_MASK ~(FFS_ASYNC_READ|FFS_ASYNC_WRITE|FFS_ISREG)

-static void io_put_identity(struct io_uring_task *tctx, struct io_kiocb *req) +static inline bool io_req_ffs_set(struct io_kiocb *req) { - if (req->work.identity == &tctx->__identity) - return; - if (refcount_dec_and_test(&req->work.identity->count)) - kfree(req->work.identity); + return IS_ENABLED(CONFIG_64BIT) && (req->flags & REQ_F_FIXED_FILE); }

-static void io_req_clean_work(struct io_kiocb *req) +static void io_req_track_inflight(struct io_kiocb *req) { - if (!(req->flags & REQ_F_WORK_INITIALIZED)) - return; - - req->flags &= ~REQ_F_WORK_INITIALIZED; - - if (req->work.flags & IO_WQ_WORK_MM) { - mmdrop(req->work.identity->mm); - req->work.flags &= ~IO_WQ_WORK_MM; - } -#ifdef CONFIG_BLK_CGROUP - if (req->work.flags & IO_WQ_WORK_BLKCG) { - css_put(req->work.identity->blkcg_css); - req->work.flags &= ~IO_WQ_WORK_BLKCG; - } -#endif - if (req->work.flags & IO_WQ_WORK_CREDS) { - put_cred(req->work.identity->creds); - req->work.flags &= ~IO_WQ_WORK_CREDS; - } - if (req->work.flags & IO_WQ_WORK_FS) { - struct fs_struct *fs = req->work.identity->fs; - - spin_lock(&req->work.identity->fs->lock); - if (--fs->users) - fs = NULL; - spin_unlock(&req->work.identity->fs->lock); - if (fs) - free_fs_struct(fs); - req->work.flags &= ~IO_WQ_WORK_FS; + if (!(req->flags & REQ_F_INFLIGHT)) { + req->flags |= REQ_F_INFLIGHT; + atomic_inc(&req->task->io_uring->inflight_tracked); } - if (req->flags & REQ_F_INFLIGHT) - io_req_drop_files(req); - - io_put_identity(req->task->io_uring, req); }

-/* - * Create a private copy of io_identity, since some fields don't match - * the current context. - */ -static bool io_identity_cow(struct io_kiocb *req) +static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req) { - struct io_uring_task *tctx = req->task->io_uring; - const struct cred *creds = NULL; - struct io_identity *id; - - if (req->work.flags & IO_WQ_WORK_CREDS) - creds = req->work.identity->creds; - - id = kmemdup(req->work.identity, sizeof(*id), GFP_KERNEL); - if (unlikely(!id)) { - req->work.flags |= IO_WQ_WORK_CANCEL; - return false; - } - - /* - * We can safely just re-init the creds we copied Either the field - * matches the current one, or we haven't grabbed it yet. The only - * exception is ->creds, through registered personalities, so handle - * that one separately. - */ - io_init_identity(id); - if (creds) - id->creds = creds; - - /* add one for this request */ - refcount_inc(&id->count); + if (WARN_ON_ONCE(!req->link)) + return NULL;

- /* drop tctx and req identity references, if needed */ - if (tctx->identity != &tctx->__identity && - refcount_dec_and_test(&tctx->identity->count)) - kfree(tctx->identity); - if (req->work.identity != &tctx->__identity && - refcount_dec_and_test(&req->work.identity->count)) - kfree(req->work.identity); + req->flags &= ~REQ_F_ARM_LTIMEOUT; + req->flags |= REQ_F_LINK_TIMEOUT;

- req->work.identity = id; - tctx->identity = id; - return true; + /* linked timeouts should have two refs once prep'ed */ + io_req_set_refcount(req); + __io_req_set_refcount(req->link, 2); + return req->link; }

-static bool io_grab_identity(struct io_kiocb *req) +static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req) { - const struct io_op_def *def = &io_op_defs[req->opcode]; - struct io_identity *id = req->work.identity; - struct io_ring_ctx *ctx = req->ctx; - - if (def->work_flags & IO_WQ_WORK_FSIZE) { - if (id->fsize != rlimit(RLIMIT_FSIZE)) - return false; - req->work.flags |= IO_WQ_WORK_FSIZE; - } -#ifdef CONFIG_BLK_CGROUP - if (!(req->work.flags & IO_WQ_WORK_BLKCG) && - (def->work_flags & IO_WQ_WORK_BLKCG)) { - rcu_read_lock(); - if (id->blkcg_css != blkcg_css()) { - rcu_read_unlock(); - return false; - } - /* - * This should be rare, either the cgroup is dying or the task - * is moving cgroups. Just punt to root for the handful of ios. - */ - if (css_tryget_online(id->blkcg_css)) - req->work.flags |= IO_WQ_WORK_BLKCG; - rcu_read_unlock(); - } -#endif - if (!(req->work.flags & IO_WQ_WORK_CREDS)) { - if (id->creds != current_cred()) - return false; - get_cred(id->creds); - req->work.flags |= IO_WQ_WORK_CREDS; - } -#ifdef CONFIG_AUDIT - if (!uid_eq(current->loginuid, id->loginuid) || - current->sessionid != id->sessionid) - return false; -#endif - if (!(req->work.flags & IO_WQ_WORK_FS) && - (def->work_flags & IO_WQ_WORK_FS)) { - if (current->fs != id->fs) - return false; - spin_lock(&id->fs->lock); - if (!id->fs->in_exec) { - id->fs->users++; - req->work.flags |= IO_WQ_WORK_FS; - } else { - req->work.flags |= IO_WQ_WORK_CANCEL; - } - spin_unlock(&current->fs->lock); - } - if (!(req->work.flags & IO_WQ_WORK_FILES) && - (def->work_flags & IO_WQ_WORK_FILES) && - !(req->flags & REQ_F_NO_FILE_TABLE)) { - if (id->files != current->files || - id->nsproxy != current->nsproxy) - return false; - atomic_inc(&id->files->count); - get_nsproxy(id->nsproxy); - - if (!(req->flags & REQ_F_INFLIGHT)) { - req->flags |= REQ_F_INFLIGHT; - - spin_lock_irq(&ctx->inflight_lock); - list_add(&req->inflight_entry, &ctx->inflight_list); - spin_unlock_irq(&ctx->inflight_lock); - } - req->work.flags |= IO_WQ_WORK_FILES; - } - if (!(req->work.flags & IO_WQ_WORK_MM) && - (def->work_flags & IO_WQ_WORK_MM)) { - if (id->mm != current->mm) - return false; - mmgrab(id->mm); - req->work.flags |= IO_WQ_WORK_MM; - } - - return true; + if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT))) + return NULL; + return __io_prep_linked_timeout(req); }

static void io_prep_async_work(struct io_kiocb *req) { const struct io_op_def *def = &io_op_defs[req->opcode]; struct io_ring_ctx *ctx = req->ctx; - struct io_identity *id;

- io_req_init_async(req); - id = req->work.identity; + if (!(req->flags & REQ_F_CREDS)) { + req->flags |= REQ_F_CREDS; + req->creds = get_current_cred(); + }

+ req->work.list.next = NULL; + req->work.flags = 0; if (req->flags & REQ_F_FORCE_ASYNC) req->work.flags |= IO_WQ_WORK_CONCURRENT;

@@ -1465,92 +1444,77 @@ static void io_prep_async_work(struct io_kiocb *req) if (def->unbound_nonreg_file) req->work.flags |= IO_WQ_WORK_UNBOUND; } - - /* if we fail grabbing identity, we must COW, regrab, and retry */ - if (io_grab_identity(req)) - return; - - if (!io_identity_cow(req)) - return; - - /* can't fail at this point */ - if (!io_grab_identity(req)) - WARN_ON(1); }

static void io_prep_async_link(struct io_kiocb *req) { struct io_kiocb *cur;

- io_prep_async_work(req); - if (req->flags & REQ_F_LINK_HEAD) - list_for_each_entry(cur, &req->link_list, link_list) + if (req->flags & REQ_F_LINK_TIMEOUT) { + struct io_ring_ctx *ctx = req->ctx; + + spin_lock_irq(&ctx->timeout_lock); + io_for_each_link(cur, req) io_prep_async_work(cur); + spin_unlock_irq(&ctx->timeout_lock); + } else { + io_for_each_link(cur, req) + io_prep_async_work(cur); + } }

-static struct io_kiocb *__io_queue_async_work(struct io_kiocb *req) +static void io_queue_async_work(struct io_kiocb *req, bool *locked) { struct io_ring_ctx *ctx = req->ctx; struct io_kiocb *link = io_prep_linked_timeout(req); + struct io_uring_task *tctx = req->task->io_uring;

- trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req, - &req->work, req->flags); - io_wq_enqueue(ctx->io_wq, &req->work); - return link; -} + /* must not take the lock, NULL it as a precaution */ + locked = NULL;

-static void io_queue_async_work(struct io_kiocb *req) -{ - struct io_kiocb *link; + BUG_ON(!tctx); + BUG_ON(!tctx->io_wq);

/* init ->work of the whole link before punting */ io_prep_async_link(req); - link = __io_queue_async_work(req);

+ /* + * Not expected to happen, but if we do have a bug where this _can_ + * happen, catch it here and ensure the request is marked as + * canceled. That will make io-wq go through the usual work cancel + * procedure rather than attempt to run this request (or create a new + * worker for it). + */ + if (WARN_ON_ONCE(!same_thread_group(req->task, current))) + req->work.flags |= IO_WQ_WORK_CANCEL; + + trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req, + &req->work, req->flags); + io_wq_enqueue(tctx->io_wq, &req->work); if (link) io_queue_linked_timeout(link); }

static void io_kill_timeout(struct io_kiocb *req, int status) + __must_hold(&req->ctx->completion_lock) + __must_hold(&req->ctx->timeout_lock) { struct io_timeout_data *io = req->async_data; - int ret;

- ret = hrtimer_try_to_cancel(&io->timer); - if (ret != -1) { + if (hrtimer_try_to_cancel(&io->timer) != -1) { if (status) - req_set_fail_links(req); + req_set_fail(req); atomic_set(&req->ctx->cq_timeouts, atomic_read(&req->ctx->cq_timeouts) + 1); list_del_init(&req->timeout.list); - io_cqring_fill_event(req, status); - io_put_req_deferred(req, 1); - } -} - -/* - * Returns true if we found and killed one or more timeouts - */ -static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk, - struct files_struct *files) -{ - struct io_kiocb *req, *tmp; - int canceled = 0; - - spin_lock_irq(&ctx->completion_lock); - list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) { - if (io_match_task(req, tsk, files)) { - io_kill_timeout(req, -ECANCELED); - canceled++; - } + io_fill_cqe_req(req, status, 0); + io_put_req_deferred(req); } - spin_unlock_irq(&ctx->completion_lock); - return canceled != 0; }

-static void __io_queue_deferred(struct io_ring_ctx *ctx) +static void io_queue_deferred(struct io_ring_ctx *ctx) { - do { + while (!list_empty(&ctx->defer_list)) { struct io_defer_entry *de = list_first_entry(&ctx->defer_list, struct io_defer_entry, list);

@@ -1559,19 +1523,16 @@ static void __io_queue_deferred(struct io_ring_ctx *ctx) list_del_init(&de->list); io_req_task_queue(de->req); kfree(de); - } while (!list_empty(&ctx->defer_list)); + } }

static void io_flush_timeouts(struct io_ring_ctx *ctx) + __must_hold(&ctx->completion_lock) { + u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts); struct io_kiocb *req, *tmp; - u32 seq; - - if (list_empty(&ctx->timeout_list)) - return; - - seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);

+ spin_lock_irq(&ctx->timeout_lock); list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) { u32 events_needed, events_got;

@@ -1592,441 +1553,564 @@ static void io_flush_timeouts(struct io_ring_ctx *ctx)

io_kill_timeout(req, 0); } - ctx->cq_last_tm_flush = seq; + spin_unlock_irq(&ctx->timeout_lock); }

-static void io_commit_cqring(struct io_ring_ctx *ctx) +static void __io_commit_cqring_flush(struct io_ring_ctx *ctx) { - io_flush_timeouts(ctx); - __io_commit_cqring(ctx); + if (ctx->off_timeout_used) + io_flush_timeouts(ctx); + if (ctx->drain_active) + io_queue_deferred(ctx); +}

- if (unlikely(!list_empty(&ctx->defer_list))) - __io_queue_deferred(ctx); +static inline void io_commit_cqring(struct io_ring_ctx *ctx) +{ + if (unlikely(ctx->off_timeout_used || ctx->drain_active)) + __io_commit_cqring_flush(ctx); + /* order cqe stores with ring update */ + smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail); }

static inline bool io_sqring_full(struct io_ring_ctx *ctx) { struct io_rings *r = ctx->rings;

- return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == r->sq_ring_entries; + return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries; }

-static struct io_uring_cqe *io_get_cqring(struct io_ring_ctx *ctx) +static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx) +{ + return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head); +} + +static inline struct io_uring_cqe *io_get_cqe(struct io_ring_ctx *ctx) { struct io_rings *rings = ctx->rings; - unsigned tail; + unsigned tail, mask = ctx->cq_entries - 1;

- tail = ctx->cached_cq_tail; /* * writes to the cq entry need to come after reading head; the * control dependency is enough as we're using WRITE_ONCE to * fill the cq entry */ - if (tail - READ_ONCE(rings->cq.head) == rings->cq_ring_entries) + if (__io_cqring_events(ctx) == ctx->cq_entries) return NULL;

- ctx->cached_cq_tail++; - return &rings->cqes[tail & ctx->cq_mask]; + tail = ctx->cached_cq_tail++; + return &rings->cqes[tail & mask]; }

static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx) { - if (!ctx->cq_ev_fd) + if (likely(!ctx->cq_ev_fd)) return false; if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED) return false; - if (!ctx->eventfd_async) - return true; - return io_wq_current_is_worker(); + return !ctx->eventfd_async || io_wq_current_is_worker(); }

+/* + * This should only get called when at least one event has been posted. + * Some applications rely on the eventfd notification count only changing + * IFF a new CQE has been added to the CQ ring. There's no depedency on + * 1:1 relationship between how many times this function is called (and + * hence the eventfd count) and number of CQEs posted to the CQ ring. + */ static void io_cqring_ev_posted(struct io_ring_ctx *ctx) { - if (wq_has_sleeper(&ctx->cq_wait)) { - wake_up_interruptible(&ctx->cq_wait); - kill_fasync(&ctx->cq_fasync, SIGIO, POLL_IN); - } - if (waitqueue_active(&ctx->wait)) - wake_up(&ctx->wait); + /* + * wake_up_all() may seem excessive, but io_wake_function() and + * io_should_wake() handle the termination of the loop and only + * wake as many waiters as we need to. + */ + if (wq_has_sleeper(&ctx->cq_wait)) + wake_up_all(&ctx->cq_wait); if (ctx->sq_data && waitqueue_active(&ctx->sq_data->wait)) wake_up(&ctx->sq_data->wait); if (io_should_trigger_evfd(ctx)) eventfd_signal(ctx->cq_ev_fd, 1); + if (waitqueue_active(&ctx->poll_wait)) + wake_up_interruptible(&ctx->poll_wait); }

-static void io_cqring_mark_overflow(struct io_ring_ctx *ctx) +static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx) { - if (list_empty(&ctx->cq_overflow_list)) { - clear_bit(0, &ctx->sq_check_overflow); - clear_bit(0, &ctx->cq_check_overflow); - ctx->rings->sq_flags &= ~IORING_SQ_CQ_OVERFLOW; + /* see waitqueue_active() comment */ + smp_mb(); + + if (ctx->flags & IORING_SETUP_SQPOLL) { + if (waitqueue_active(&ctx->cq_wait)) + wake_up_all(&ctx->cq_wait); } + if (io_should_trigger_evfd(ctx)) + eventfd_signal(ctx->cq_ev_fd, 1); + if (waitqueue_active(&ctx->poll_wait)) + wake_up_interruptible(&ctx->poll_wait); }

/* Returns true if there are no backlogged entries after the flush */ -static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force, - struct task_struct *tsk, - struct files_struct *files) +static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force) { - struct io_rings *rings = ctx->rings; - struct io_kiocb *req, *tmp; - struct io_uring_cqe *cqe; - unsigned long flags; - LIST_HEAD(list); - - if (!force) { - if ((ctx->cached_cq_tail - READ_ONCE(rings->cq.head) == - rings->cq_ring_entries)) - return false; - } + bool all_flushed, posted;

- spin_lock_irqsave(&ctx->completion_lock, flags); + if (!force && __io_cqring_events(ctx) == ctx->cq_entries) + return false;

- cqe = NULL; - list_for_each_entry_safe(req, tmp, &ctx->cq_overflow_list, compl.list) { - if (!io_match_task(req, tsk, files)) - continue; + posted = false; + spin_lock(&ctx->completion_lock); + while (!list_empty(&ctx->cq_overflow_list)) { + struct io_uring_cqe *cqe = io_get_cqe(ctx); + struct io_overflow_cqe *ocqe;

- cqe = io_get_cqring(ctx); if (!cqe && !force) break; + ocqe = list_first_entry(&ctx->cq_overflow_list, + struct io_overflow_cqe, list); + if (cqe) + memcpy(cqe, &ocqe->cqe, sizeof(*cqe)); + else + io_account_cq_overflow(ctx);

- list_move(&req->compl.list, &list); - if (cqe) { - WRITE_ONCE(cqe->user_data, req->user_data); - WRITE_ONCE(cqe->res, req->result); - WRITE_ONCE(cqe->flags, req->compl.cflags); - } else { - ctx->cached_cq_overflow++; - WRITE_ONCE(ctx->rings->cq_overflow, - ctx->cached_cq_overflow); - } + posted = true; + list_del(&ocqe->list); + kfree(ocqe); }

- io_commit_cqring(ctx); - io_cqring_mark_overflow(ctx); - - spin_unlock_irqrestore(&ctx->completion_lock, flags); - io_cqring_ev_posted(ctx); - - while (!list_empty(&list)) { - req = list_first_entry(&list, struct io_kiocb, compl.list); - list_del(&req->compl.list); - io_put_req(req); + all_flushed = list_empty(&ctx->cq_overflow_list); + if (all_flushed) { + clear_bit(0, &ctx->check_cq_overflow); + WRITE_ONCE(ctx->rings->sq_flags, + ctx->rings->sq_flags & ~IORING_SQ_CQ_OVERFLOW); }

- return cqe != NULL; + if (posted) + io_commit_cqring(ctx); + spin_unlock(&ctx->completion_lock); + if (posted) + io_cqring_ev_posted(ctx); + return all_flushed; }

-static void io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force, - struct task_struct *tsk, - struct files_struct *files) +static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx) { - if (test_bit(0, &ctx->cq_check_overflow)) { + bool ret = true; + + if (test_bit(0, &ctx->check_cq_overflow)) { /* iopoll syncs against uring_lock, not completion_lock */ if (ctx->flags & IORING_SETUP_IOPOLL) mutex_lock(&ctx->uring_lock); - __io_cqring_overflow_flush(ctx, force, tsk, files); + ret = __io_cqring_overflow_flush(ctx, false); if (ctx->flags & IORING_SETUP_IOPOLL) mutex_unlock(&ctx->uring_lock); } + + return ret; }

-static void __io_cqring_fill_event(struct io_kiocb *req, long res, - unsigned int cflags) +/* must to be called somewhat shortly after putting a request */ +static inline void io_put_task(struct task_struct *task, int nr) { - struct io_ring_ctx *ctx = req->ctx; - struct io_uring_cqe *cqe; - - trace_io_uring_complete(ctx, req->user_data, res); + struct io_uring_task *tctx = task->io_uring;

- /* - * If we can't get a cq entry, userspace overflowed the - * submission (by quite a lot). Increment the overflow count in - * the ring. - */ - cqe = io_get_cqring(ctx); - if (likely(cqe)) { - WRITE_ONCE(cqe->user_data, req->user_data); - WRITE_ONCE(cqe->res, res); - WRITE_ONCE(cqe->flags, cflags); - } else if (ctx->cq_overflow_flushed || - atomic_read(&req->task->io_uring->in_idle)) { - /* - * If we're in ring overflow flush mode, or in task cancel mode, - * then we cannot store the request for later flushing, we need - * to drop it on the floor. - */ - ctx->cached_cq_overflow++; - WRITE_ONCE(ctx->rings->cq_overflow, ctx->cached_cq_overflow); + if (likely(task == current)) { + tctx->cached_refs += nr; } else { - if (list_empty(&ctx->cq_overflow_list)) { - set_bit(0, &ctx->sq_check_overflow); - set_bit(0, &ctx->cq_check_overflow); - ctx->rings->sq_flags |= IORING_SQ_CQ_OVERFLOW; - } - io_clean_op(req); - req->result = res; - req->compl.cflags = cflags; - refcount_inc(&req->refs); - list_add_tail(&req->compl.list, &ctx->cq_overflow_list); + percpu_counter_sub(&tctx->inflight, nr); + if (unlikely(atomic_read(&tctx->in_idle))) + wake_up(&tctx->wait); + put_task_struct_many(task, nr); } }

-static void io_cqring_fill_event(struct io_kiocb *req, long res) +static void io_task_refs_refill(struct io_uring_task *tctx) { - __io_cqring_fill_event(req, res, 0); + unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR; + + percpu_counter_add(&tctx->inflight, refill); + refcount_add(refill, &current->usage); + tctx->cached_refs += refill; }

-static void io_cqring_add_event(struct io_kiocb *req, long res, long cflags) +static inline void io_get_task_refs(int nr) { - struct io_ring_ctx *ctx = req->ctx; - unsigned long flags; - - spin_lock_irqsave(&ctx->completion_lock, flags); - __io_cqring_fill_event(req, res, cflags); - io_commit_cqring(ctx); - spin_unlock_irqrestore(&ctx->completion_lock, flags); + struct io_uring_task *tctx = current->io_uring;

- io_cqring_ev_posted(ctx); + tctx->cached_refs -= nr; + if (unlikely(tctx->cached_refs < 0)) + io_task_refs_refill(tctx); }

-static void io_submit_flush_completions(struct io_comp_state *cs) +static __cold void io_uring_drop_tctx_refs(struct task_struct *task) { - struct io_ring_ctx *ctx = cs->ctx; + struct io_uring_task *tctx = task->io_uring; + unsigned int refs = tctx->cached_refs;

- spin_lock_irq(&ctx->completion_lock); - while (!list_empty(&cs->list)) { - struct io_kiocb *req; + if (refs) { + tctx->cached_refs = 0; + percpu_counter_sub(&tctx->inflight, refs); + put_task_struct_many(task, refs); + } +}

- req = list_first_entry(&cs->list, struct io_kiocb, compl.list); - list_del(&req->compl.list); - __io_cqring_fill_event(req, req->result, req->compl.cflags); +static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data, + s32 res, u32 cflags) +{ + struct io_overflow_cqe *ocqe;

+ ocqe = kmalloc(sizeof(*ocqe), GFP_ATOMIC | __GFP_ACCOUNT); + if (!ocqe) { /* - * io_free_req() doesn't care about completion_lock unless one - * of these flags is set. REQ_F_WORK_INITIALIZED is in the list - * because of a potential deadlock with req->work.fs->lock + * If we're in ring overflow flush mode, or in task cancel mode, + * or cannot allocate an overflow entry, then we need to drop it + * on the floor. */ - if (req->flags & (REQ_F_FAIL_LINK|REQ_F_LINK_TIMEOUT - |REQ_F_WORK_INITIALIZED)) { - spin_unlock_irq(&ctx->completion_lock); - io_put_req(req); - spin_lock_irq(&ctx->completion_lock); - } else { - io_put_req(req); - } + io_account_cq_overflow(ctx); + return false; } - io_commit_cqring(ctx); - spin_unlock_irq(&ctx->completion_lock); + if (list_empty(&ctx->cq_overflow_list)) { + set_bit(0, &ctx->check_cq_overflow); + WRITE_ONCE(ctx->rings->sq_flags, + ctx->rings->sq_flags | IORING_SQ_CQ_OVERFLOW);

- io_cqring_ev_posted(ctx); - cs->nr = 0; + } + ocqe->cqe.user_data = user_data; + ocqe->cqe.res = res; + ocqe->cqe.flags = cflags; + list_add_tail(&ocqe->list, &ctx->cq_overflow_list); + return true; }

-static void __io_req_complete(struct io_kiocb *req, long res, unsigned cflags, - struct io_comp_state *cs) +static inline bool __io_fill_cqe(struct io_ring_ctx *ctx, u64 user_data, + s32 res, u32 cflags) { - if (!cs) { - io_cqring_add_event(req, res, cflags); - io_put_req(req); - } else { - io_clean_op(req); - req->result = res; - req->compl.cflags = cflags; - list_add_tail(&req->compl.list, &cs->list); - if (++cs->nr >= 32) - io_submit_flush_completions(cs); + struct io_uring_cqe *cqe; + + trace_io_uring_complete(ctx, user_data, res, cflags); + + /* + * If we can't get a cq entry, userspace overflowed the + * submission (by quite a lot). Increment the overflow count in + * the ring. + */ + cqe = io_get_cqe(ctx); + if (likely(cqe)) { + WRITE_ONCE(cqe->user_data, user_data); + WRITE_ONCE(cqe->res, res); + WRITE_ONCE(cqe->flags, cflags); + return true; } + return io_cqring_event_overflow(ctx, user_data, res, cflags); }

-static void io_req_complete(struct io_kiocb *req, long res) +static noinline void io_fill_cqe_req(struct io_kiocb *req, s32 res, u32 cflags) { - __io_req_complete(req, res, 0, NULL); + __io_fill_cqe(req->ctx, req->user_data, res, cflags); }

-static inline bool io_is_fallback_req(struct io_kiocb *req) +static noinline bool io_fill_cqe_aux(struct io_ring_ctx *ctx, u64 user_data, + s32 res, u32 cflags) { - return req == (struct io_kiocb *) - ((unsigned long) req->ctx->fallback_req & ~1UL); + ctx->cq_extra++; + return __io_fill_cqe(ctx, user_data, res, cflags); }

-static struct io_kiocb *io_get_fallback_req(struct io_ring_ctx *ctx) +static void io_req_complete_post(struct io_kiocb *req, s32 res, + u32 cflags) { - struct io_kiocb *req; - - req = ctx->fallback_req; - if (!test_and_set_bit_lock(0, (unsigned long *) &ctx->fallback_req)) - return req; + struct io_ring_ctx *ctx = req->ctx;

- return NULL; -} + spin_lock(&ctx->completion_lock); + __io_fill_cqe(ctx, req->user_data, res, cflags); + /* + * If we're the last reference to this request, add to our locked + * free_list cache. + */ + if (req_ref_put_and_test(req)) { + if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) { + if (req->flags & IO_DISARM_MASK) + io_disarm_next(req); + if (req->link) { + io_req_task_queue(req->link); + req->link = NULL; + } + } + io_dismantle_req(req); + io_put_task(req->task, 1); + list_add(&req->inflight_entry, &ctx->locked_free_list); + ctx->locked_free_nr++; + } else { + if (!percpu_ref_tryget(&ctx->refs)) + req = NULL; + } + io_commit_cqring(ctx); + spin_unlock(&ctx->completion_lock);

-static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx, - struct io_submit_state *state) + if (req) { + io_cqring_ev_posted(ctx); + percpu_ref_put(&ctx->refs); + } +} + +static inline bool io_req_needs_clean(struct io_kiocb *req) { - if (!state->free_reqs) { - gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; - size_t sz; - int ret; + return req->flags & IO_REQ_CLEAN_FLAGS; +} + +static inline void io_req_complete_state(struct io_kiocb *req, s32 res, + u32 cflags) +{ + if (io_req_needs_clean(req)) + io_clean_op(req); + req->result = res; + req->compl.cflags = cflags; + req->flags |= REQ_F_COMPLETE_INLINE; +}

- sz = min_t(size_t, state->ios_left, ARRAY_SIZE(state->reqs)); - ret = kmem_cache_alloc_bulk(req_cachep, gfp, sz, state->reqs); +static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags, + s32 res, u32 cflags) +{ + if (issue_flags & IO_URING_F_COMPLETE_DEFER) + io_req_complete_state(req, res, cflags); + else + io_req_complete_post(req, res, cflags); +}

- /* - * Bulk alloc is all-or-nothing. If we fail to get a batch, - * retry single alloc to be on the safe side. - */ - if (unlikely(ret <= 0)) { - state->reqs[0] = kmem_cache_alloc(req_cachep, gfp); - if (!state->reqs[0]) - goto fallback; - ret = 1; - } - state->free_reqs = ret; +static inline void io_req_complete(struct io_kiocb *req, s32 res) +{ + __io_req_complete(req, 0, res, 0); +} + +static void io_req_complete_failed(struct io_kiocb *req, s32 res) +{ + req_set_fail(req); + io_req_complete_post(req, res, 0); +} + +static void io_req_complete_fail_submit(struct io_kiocb *req) +{ + /* + * We don't submit, fail them all, for that replace hardlinks with + * normal links. Extra REQ_F_LINK is tolerated. + */ + req->flags &= ~REQ_F_HARDLINK; + req->flags |= REQ_F_LINK; + io_req_complete_failed(req, req->result); +} + +/* + * Don't initialise the fields below on every allocation, but do that in + * advance and keep them valid across allocations. + */ +static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx) +{ + req->ctx = ctx; + req->link = NULL; + req->async_data = NULL; + /* not necessary, but safer to zero */ + req->result = 0; +} + +static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx, + struct io_submit_state *state) +{ + spin_lock(&ctx->completion_lock); + list_splice_init(&ctx->locked_free_list, &state->free_list); + ctx->locked_free_nr = 0; + spin_unlock(&ctx->completion_lock); +} + +/* Returns true IFF there are requests in the cache */ +static bool io_flush_cached_reqs(struct io_ring_ctx *ctx) +{ + struct io_submit_state *state = &ctx->submit_state; + int nr; + + /* + * If we have more than a batch's worth of requests in our IRQ side + * locked cache, grab the lock and move them over to our submission + * side cache. + */ + if (READ_ONCE(ctx->locked_free_nr) > IO_COMPL_BATCH) + io_flush_cached_locked_reqs(ctx, state); + + nr = state->free_reqs; + while (!list_empty(&state->free_list)) { + struct io_kiocb *req = list_first_entry(&state->free_list, + struct io_kiocb, inflight_entry); + + list_del(&req->inflight_entry); + state->reqs[nr++] = req; + if (nr == ARRAY_SIZE(state->reqs)) + break; + } + + state->free_reqs = nr; + return nr != 0; +} + +/* + * A request might get retired back into the request caches even before opcode + * handlers and io_issue_sqe() are done with it, e.g. inline completion path. + * Because of that, io_alloc_req() should be called only under ->uring_lock + * and with extra caution to not get a request that is still worked on. + */ +static struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx) + __must_hold(&ctx->uring_lock) +{ + struct io_submit_state *state = &ctx->submit_state; + gfp_t gfp = GFP_KERNEL | __GFP_NOWARN; + int ret, i; + + BUILD_BUG_ON(ARRAY_SIZE(state->reqs) < IO_REQ_ALLOC_BATCH); + + if (likely(state->free_reqs || io_flush_cached_reqs(ctx))) + goto got_req; + + ret = kmem_cache_alloc_bulk(req_cachep, gfp, IO_REQ_ALLOC_BATCH, + state->reqs); + + /* + * Bulk alloc is all-or-nothing. If we fail to get a batch, + * retry single alloc to be on the safe side. + */ + if (unlikely(ret <= 0)) { + state->reqs[0] = kmem_cache_alloc(req_cachep, gfp); + if (!state->reqs[0]) + return NULL; + ret = 1; }

+ for (i = 0; i < ret; i++) + io_preinit_req(state->reqs[i], ctx); + state->free_reqs = ret; +got_req: state->free_reqs--; return state->reqs[state->free_reqs]; -fallback: - return io_get_fallback_req(ctx); }

-static inline void io_put_file(struct io_kiocb *req, struct file *file, - bool fixed) +static inline void io_put_file(struct file *file) { - if (fixed) - percpu_ref_put(req->fixed_file_refs); - else + if (file) fput(file); }

static void io_dismantle_req(struct io_kiocb *req) { - io_clean_op(req); + unsigned int flags = req->flags;

- if (req->async_data) + if (io_req_needs_clean(req)) + io_clean_op(req); + if (!(flags & REQ_F_FIXED_FILE)) + io_put_file(req->file); + if (req->fixed_rsrc_refs) + percpu_ref_put(req->fixed_rsrc_refs); + if (req->async_data) { kfree(req->async_data); - if (req->file) - io_put_file(req, req->file, (req->flags & REQ_F_FIXED_FILE)); - - io_req_clean_work(req); + req->async_data = NULL; + } }

static void __io_free_req(struct io_kiocb *req) { - struct io_uring_task *tctx = req->task->io_uring; struct io_ring_ctx *ctx = req->ctx;

io_dismantle_req(req); + io_put_task(req->task, 1);

- percpu_counter_dec(&tctx->inflight); - if (atomic_read(&tctx->in_idle)) - wake_up(&tctx->wait); - put_task_struct(req->task); + spin_lock(&ctx->completion_lock); + list_add(&req->inflight_entry, &ctx->locked_free_list); + ctx->locked_free_nr++; + spin_unlock(&ctx->completion_lock);

- if (likely(!io_is_fallback_req(req))) - kmem_cache_free(req_cachep, req); - else - clear_bit_unlock(0, (unsigned long *) &ctx->fallback_req); percpu_ref_put(&ctx->refs); }

-static void io_kill_linked_timeout(struct io_kiocb *req) +static inline void io_remove_next_linked(struct io_kiocb *req) { - struct io_ring_ctx *ctx = req->ctx; - struct io_kiocb *link; - bool cancelled = false; - unsigned long flags; + struct io_kiocb *nxt = req->link;

- spin_lock_irqsave(&ctx->completion_lock, flags); - link = list_first_entry_or_null(&req->link_list, struct io_kiocb, - link_list); - /* - * Can happen if a linked timeout fired and link had been like - * req -> link t-out -> link t-out [-> ...] - */ - if (link && (link->flags & REQ_F_LTIMEOUT_ACTIVE)) { - struct io_timeout_data *io = link->async_data; - int ret; - - list_del_init(&link->link_list); - ret = hrtimer_try_to_cancel(&io->timer); - if (ret != -1) { - io_cqring_fill_event(link, -ECANCELED); - io_commit_cqring(ctx); - cancelled = true; - } - } - req->flags &= ~REQ_F_LINK_TIMEOUT; - spin_unlock_irqrestore(&ctx->completion_lock, flags); - - if (cancelled) { - io_cqring_ev_posted(ctx); - io_put_req(link); - } + req->link = nxt->link; + nxt->link = NULL; }

-static struct io_kiocb *io_req_link_next(struct io_kiocb *req) +static bool io_kill_linked_timeout(struct io_kiocb *req) + __must_hold(&req->ctx->completion_lock) + __must_hold(&req->ctx->timeout_lock) { - struct io_kiocb *nxt; + struct io_kiocb *link = req->link;

- /* - * The list should never be empty when we are called here. But could - * potentially happen if the chain is messed up, check to be on the - * safe side. - */ - if (unlikely(list_empty(&req->link_list))) - return NULL; + if (link && link->opcode == IORING_OP_LINK_TIMEOUT) { + struct io_timeout_data *io = link->async_data;

- nxt = list_first_entry(&req->link_list, struct io_kiocb, link_list); - list_del_init(&req->link_list); - if (!list_empty(&nxt->link_list)) - nxt->flags |= REQ_F_LINK_HEAD; - return nxt; + io_remove_next_linked(req); + link->timeout.head = NULL; + if (hrtimer_try_to_cancel(&io->timer) != -1) { + list_del(&link->timeout.list); + io_fill_cqe_req(link, -ECANCELED, 0); + io_put_req_deferred(link); + return true; + } + } + return false; }

-/* - * Called if REQ_F_LINK_HEAD is set, and we fail the head request - */ static void io_fail_links(struct io_kiocb *req) + __must_hold(&req->ctx->completion_lock) { - struct io_ring_ctx *ctx = req->ctx; - unsigned long flags; + struct io_kiocb *nxt, *link = req->link;

- spin_lock_irqsave(&ctx->completion_lock, flags); - while (!list_empty(&req->link_list)) { - struct io_kiocb *link = list_first_entry(&req->link_list, - struct io_kiocb, link_list); + req->link = NULL; + while (link) { + long res = -ECANCELED;

- list_del_init(&link->link_list); - trace_io_uring_fail_link(req, link); + if (link->flags & REQ_F_FAIL) + res = link->result;

- io_cqring_fill_event(link, -ECANCELED); + nxt = link->link; + link->link = NULL;

- /* - * It's ok to free under spinlock as they're not linked anymore, - * but avoid REQ_F_WORK_INITIALIZED because it may deadlock on - * work.fs->lock. - */ - if (link->flags & REQ_F_WORK_INITIALIZED) - io_put_req_deferred(link, 2); - else - io_double_put_req(link); + trace_io_uring_fail_link(req, link); + io_fill_cqe_req(link, res, 0); + io_put_req_deferred(link); + link = nxt; } +}

- io_commit_cqring(ctx); - spin_unlock_irqrestore(&ctx->completion_lock, flags); +static bool io_disarm_next(struct io_kiocb *req) + __must_hold(&req->ctx->completion_lock) +{ + bool posted = false;

- io_cqring_ev_posted(ctx); + if (req->flags & REQ_F_ARM_LTIMEOUT) { + struct io_kiocb *link = req->link; + + req->flags &= ~REQ_F_ARM_LTIMEOUT; + if (link && link->opcode == IORING_OP_LINK_TIMEOUT) { + io_remove_next_linked(req); + io_fill_cqe_req(link, -ECANCELED, 0); + io_put_req_deferred(link); + posted = true; + } + } else if (req->flags & REQ_F_LINK_TIMEOUT) { + struct io_ring_ctx *ctx = req->ctx; + + spin_lock_irq(&ctx->timeout_lock); + posted = io_kill_linked_timeout(req); + spin_unlock_irq(&ctx->timeout_lock); + } + if (unlikely((req->flags & REQ_F_FAIL) && + !(req->flags & REQ_F_HARDLINK))) { + posted |= (req->link != NULL); + io_fail_links(req); + } + return posted; }

static struct io_kiocb *__io_req_find_next(struct io_kiocb *req) { - req->flags &= ~REQ_F_LINK_HEAD; - if (req->flags & REQ_F_LINK_TIMEOUT) - io_kill_linked_timeout(req); + struct io_kiocb *nxt;

/* * If LINK is set, we have dependent requests in this chain. If we @@ -2034,28 +2118,112 @@ static struct io_kiocb *__io_req_find_next(struct io_kiocb *req) * dependencies to the next request. In case of failure, fail the rest * of the chain. */ - if (likely(!(req->flags & REQ_F_FAIL_LINK))) - return io_req_link_next(req); - io_fail_links(req); - return NULL; + if (req->flags & IO_DISARM_MASK) { + struct io_ring_ctx *ctx = req->ctx; + bool posted; + + spin_lock(&ctx->completion_lock); + posted = io_disarm_next(req); + if (posted) + io_commit_cqring(req->ctx); + spin_unlock(&ctx->completion_lock); + if (posted) + io_cqring_ev_posted(ctx); + } + nxt = req->link; + req->link = NULL; + return nxt; }

-static struct io_kiocb *io_req_find_next(struct io_kiocb *req) +static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req) { - if (likely(!(req->flags & REQ_F_LINK_HEAD))) + if (likely(!(req->flags & (REQ_F_LINK|REQ_F_HARDLINK)))) return NULL; return __io_req_find_next(req); }

-static int io_req_task_work_add(struct io_kiocb *req, bool twa_signal_ok) +static void ctx_flush_and_put(struct io_ring_ctx *ctx, bool *locked) +{ + if (!ctx) + return; + if (*locked) { + if (ctx->submit_state.compl_nr) + io_submit_flush_completions(ctx); + mutex_unlock(&ctx->uring_lock); + *locked = false; + } + percpu_ref_put(&ctx->refs); +} + +static void tctx_task_work(struct callback_head *cb) +{ + bool locked = false; + struct io_ring_ctx *ctx = NULL; + struct io_uring_task *tctx = container_of(cb, struct io_uring_task, + task_work); + + while (1) { + struct io_wq_work_node *node; + + if (!tctx->task_list.first && locked && ctx->submit_state.compl_nr) + io_submit_flush_completions(ctx); + + spin_lock_irq(&tctx->task_lock); + node = tctx->task_list.first; + INIT_WQ_LIST(&tctx->task_list); + if (!node) + tctx->task_running = false; + spin_unlock_irq(&tctx->task_lock); + if (!node) + break; + + do { + struct io_wq_work_node *next = node->next; + struct io_kiocb *req = container_of(node, struct io_kiocb, + io_task_work.node); + + if (req->ctx != ctx) { + ctx_flush_and_put(ctx, &locked); + ctx = req->ctx; + /* if not contended, grab and improve batching */ + locked = mutex_trylock(&ctx->uring_lock); + percpu_ref_get(&ctx->refs); + } + req->io_task_work.func(req, &locked); + node = next; + } while (node); + + cond_resched(); + } + + ctx_flush_and_put(ctx, &locked); + + /* relaxed read is enough as only the task itself sets ->in_idle */ + if (unlikely(atomic_read(&tctx->in_idle))) + io_uring_drop_tctx_refs(current); +} + +static void io_req_task_work_add(struct io_kiocb *req) { struct task_struct *tsk = req->task; - struct io_ring_ctx *ctx = req->ctx; + struct io_uring_task *tctx = tsk->io_uring; enum task_work_notify_mode notify; - int ret; + struct io_wq_work_node *node; + unsigned long flags; + bool running; + + WARN_ON_ONCE(!tctx); + + spin_lock_irqsave(&tctx->task_lock, flags); + wq_list_add_tail(&req->io_task_work.node, &tctx->task_list); + running = tctx->task_running; + if (!running) + tctx->task_running = true; + spin_unlock_irqrestore(&tctx->task_lock, flags);

- if (tsk->flags & PF_EXITING) - return -ESRCH; + /* task_work already pending, we're done */ + if (running) + return;

/* * SQPOLL kernel thread doesn't need notification, just a wakeup. For @@ -2063,85 +2231,68 @@ static int io_req_task_work_add(struct io_kiocb *req, bool twa_signal_ok) * processing task_work. There's no reliable way to tell if TWA_RESUME * will do the job. */ - notify = TWA_NONE; - if (!(ctx->flags & IORING_SETUP_SQPOLL) && twa_signal_ok) - notify = TWA_SIGNAL; - - ret = task_work_add(tsk, &req->task_work, notify); - if (!ret) + notify = (req->ctx->flags & IORING_SETUP_SQPOLL) ? TWA_NONE : TWA_SIGNAL; + if (!task_work_add(tsk, &tctx->task_work, notify)) { wake_up_process(tsk); + return; + }

- return ret; -} - -static void __io_req_task_cancel(struct io_kiocb *req, int error) -{ - struct io_ring_ctx *ctx = req->ctx; - - spin_lock_irq(&ctx->completion_lock); - io_cqring_fill_event(req, error); - io_commit_cqring(ctx); - spin_unlock_irq(&ctx->completion_lock); + spin_lock_irqsave(&tctx->task_lock, flags); + tctx->task_running = false; + node = tctx->task_list.first; + INIT_WQ_LIST(&tctx->task_list); + spin_unlock_irqrestore(&tctx->task_lock, flags);

- io_cqring_ev_posted(ctx); - req_set_fail_links(req); - io_double_put_req(req); + while (node) { + req = container_of(node, struct io_kiocb, io_task_work.node); + node = node->next; + if (llist_add(&req->io_task_work.fallback_node, + &req->ctx->fallback_llist)) + schedule_delayed_work(&req->ctx->fallback_work, 1); + } }

-static void io_req_task_cancel(struct callback_head *cb) +static void io_req_task_cancel(struct io_kiocb *req, bool *locked) { - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); struct io_ring_ctx *ctx = req->ctx;

- mutex_lock(&ctx->uring_lock); - __io_req_task_cancel(req, -ECANCELED); - mutex_unlock(&ctx->uring_lock); - percpu_ref_put(&ctx->refs); + /* not needed for normal modes, but SQPOLL depends on it */ + io_tw_lock(ctx, locked); + io_req_complete_failed(req, req->result); }

-static void __io_req_task_submit(struct io_kiocb *req) +static void io_req_task_submit(struct io_kiocb *req, bool *locked) { struct io_ring_ctx *ctx = req->ctx;

- mutex_lock(&ctx->uring_lock); - if (!ctx->sqo_dead && !__io_sq_thread_acquire_mm(ctx)) - __io_queue_sqe(req, NULL); + io_tw_lock(ctx, locked); + /* req->task == current here, checking PF_EXITING is safe */ + if (likely(!(req->task->flags & PF_EXITING))) + __io_queue_sqe(req); else - __io_req_task_cancel(req, -EFAULT); - mutex_unlock(&ctx->uring_lock); - - if (ctx->flags & IORING_SETUP_SQPOLL) - io_sq_thread_drop_mm(); + io_req_complete_failed(req, -EFAULT); }

-static void io_req_task_submit(struct callback_head *cb) +static void io_req_task_queue_fail(struct io_kiocb *req, int ret) { - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); - struct io_ring_ctx *ctx = req->ctx; - - __io_req_task_submit(req); - percpu_ref_put(&ctx->refs); + req->result = ret; + req->io_task_work.func = io_req_task_cancel; + io_req_task_work_add(req); }

static void io_req_task_queue(struct io_kiocb *req) { - int ret; - - init_task_work(&req->task_work, io_req_task_submit); - percpu_ref_get(&req->ctx->refs); - - ret = io_req_task_work_add(req, true); - if (unlikely(ret)) { - struct task_struct *tsk; + req->io_task_work.func = io_req_task_submit; + io_req_task_work_add(req); +}

- init_task_work(&req->task_work, io_req_task_cancel); - tsk = io_wq_get_task(req->ctx->io_wq); - task_work_add(tsk, &req->task_work, TWA_NONE); - wake_up_process(tsk); - } +static void io_req_task_queue_reissue(struct io_kiocb *req) +{ + req->io_task_work.func = io_queue_async_work; + io_req_task_work_add(req); }

-static void io_queue_next(struct io_kiocb *req) +static inline void io_queue_next(struct io_kiocb *req) { struct io_kiocb *nxt = io_req_find_next(req);

@@ -2155,153 +2306,118 @@ static void io_free_req(struct io_kiocb *req) __io_free_req(req); }

-struct req_batch { - void *reqs[IO_IOPOLL_BATCH]; - int to_free; +static void io_free_req_work(struct io_kiocb *req, bool *locked) +{ + io_free_req(req); +}

+struct req_batch { struct task_struct *task; int task_refs; + int ctx_refs; };

static inline void io_init_req_batch(struct req_batch *rb) { - rb->to_free = 0; rb->task_refs = 0; + rb->ctx_refs = 0; rb->task = NULL; }

-static void __io_req_free_batch_flush(struct io_ring_ctx *ctx, - struct req_batch *rb) +static void io_req_free_batch_finish(struct io_ring_ctx *ctx, + struct req_batch *rb) { - kmem_cache_free_bulk(req_cachep, rb->to_free, rb->reqs); - percpu_ref_put_many(&ctx->refs, rb->to_free); - rb->to_free = 0; + if (rb->ctx_refs) + percpu_ref_put_many(&ctx->refs, rb->ctx_refs); + if (rb->task) + io_put_task(rb->task, rb->task_refs); }

-static void io_req_free_batch_finish(struct io_ring_ctx *ctx, - struct req_batch *rb) +static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req, + struct io_submit_state *state) { - if (rb->to_free) - __io_req_free_batch_flush(ctx, rb); - if (rb->task) { - struct io_uring_task *tctx = rb->task->io_uring; + io_queue_next(req); + io_dismantle_req(req);

- percpu_counter_sub(&tctx->inflight, rb->task_refs); - if (atomic_read(&tctx->in_idle)) - wake_up(&tctx->wait); - put_task_struct_many(rb->task, rb->task_refs); - rb->task = NULL; + if (req->task != rb->task) { + if (rb->task) + io_put_task(rb->task, rb->task_refs); + rb->task = req->task; + rb->task_refs = 0; } + rb->task_refs++; + rb->ctx_refs++; + + if (state->free_reqs != ARRAY_SIZE(state->reqs)) + state->reqs[state->free_reqs++] = req; + else + list_add(&req->inflight_entry, &state->free_list); }

-static void io_req_free_batch(struct req_batch *rb, struct io_kiocb *req) +static void io_submit_flush_completions(struct io_ring_ctx *ctx) + __must_hold(&ctx->uring_lock) { - if (unlikely(io_is_fallback_req(req))) { - io_free_req(req); - return; + struct io_submit_state *state = &ctx->submit_state; + int i, nr = state->compl_nr; + struct req_batch rb; + + spin_lock(&ctx->completion_lock); + for (i = 0; i < nr; i++) { + struct io_kiocb *req = state->compl_reqs[i]; + + __io_fill_cqe(ctx, req->user_data, req->result, + req->compl.cflags); } - if (req->flags & REQ_F_LINK_HEAD) - io_queue_next(req); + io_commit_cqring(ctx); + spin_unlock(&ctx->completion_lock); + io_cqring_ev_posted(ctx);

- if (req->task != rb->task) { - if (rb->task) { - struct io_uring_task *tctx = rb->task->io_uring; + io_init_req_batch(&rb); + for (i = 0; i < nr; i++) { + struct io_kiocb *req = state->compl_reqs[i];

- percpu_counter_sub(&tctx->inflight, rb->task_refs); - if (atomic_read(&tctx->in_idle)) - wake_up(&tctx->wait); - put_task_struct_many(rb->task, rb->task_refs); - } - rb->task = req->task; - rb->task_refs = 0; + if (req_ref_put_and_test(req)) + io_req_free_batch(&rb, req, &ctx->submit_state); } - rb->task_refs++;

- io_dismantle_req(req); - rb->reqs[rb->to_free++] = req; - if (unlikely(rb->to_free == ARRAY_SIZE(rb->reqs))) - __io_req_free_batch_flush(req->ctx, rb); + io_req_free_batch_finish(ctx, &rb); + state->compl_nr = 0; }

/* * Drop reference to request, return next in chain (if there is one) if this * was the last reference to this request. */ -static struct io_kiocb *io_put_req_find_next(struct io_kiocb *req) +static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req) { struct io_kiocb *nxt = NULL;

- if (refcount_dec_and_test(&req->refs)) { + if (req_ref_put_and_test(req)) { nxt = io_req_find_next(req); __io_free_req(req); } return nxt; }

-static void io_put_req(struct io_kiocb *req) +static inline void io_put_req(struct io_kiocb *req) { - if (refcount_dec_and_test(&req->refs)) + if (req_ref_put_and_test(req)) io_free_req(req); }

-static void io_put_req_deferred_cb(struct callback_head *cb) -{ - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); - - io_free_req(req); -} - -static void io_free_req_deferred(struct io_kiocb *req) +static inline void io_put_req_deferred(struct io_kiocb *req) { - int ret; - - init_task_work(&req->task_work, io_put_req_deferred_cb); - ret = io_req_task_work_add(req, true); - if (unlikely(ret)) { - struct task_struct *tsk; - - tsk = io_wq_get_task(req->ctx->io_wq); - task_work_add(tsk, &req->task_work, TWA_NONE); - wake_up_process(tsk); + if (req_ref_put_and_test(req)) { + req->io_task_work.func = io_free_req_work; + io_req_task_work_add(req); } }

-static inline void io_put_req_deferred(struct io_kiocb *req, int refs) -{ - if (refcount_sub_and_test(refs, &req->refs)) - io_free_req_deferred(req); -} - -static struct io_wq_work *io_steal_work(struct io_kiocb *req) -{ - struct io_kiocb *nxt; - - /* - * A ref is owned by io-wq in which context we're. So, if that's the - * last one, it's safe to steal next work. False negatives are Ok, - * it just will be re-punted async in io_put_work() - */ - if (refcount_read(&req->refs) != 1) - return NULL; - - nxt = io_req_find_next(req); - return nxt ? &nxt->work : NULL; -} - -static void io_double_put_req(struct io_kiocb *req) -{ - /* drop both submit and complete references */ - if (refcount_sub_and_test(2, &req->refs)) - io_free_req(req); -} - static unsigned io_cqring_events(struct io_ring_ctx *ctx) { - struct io_rings *rings = ctx->rings; - /* See comment at the top of this file */ smp_rmb(); - return ctx->cached_cq_tail - READ_ONCE(rings->cq.head); + return __io_cqring_events(ctx); }

static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx) @@ -2327,38 +2443,23 @@ static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req) { struct io_buffer *kbuf;

+ if (likely(!(req->flags & REQ_F_BUFFER_SELECTED))) + return 0; kbuf = (struct io_buffer *) (unsigned long) req->rw.addr; return io_put_kbuf(req, kbuf); }

static inline bool io_run_task_work(void) { - /* - * Not safe to run on exiting task, and the task_work handling will - * not add work to such a task. - */ - if (unlikely(current->flags & PF_EXITING)) - return false; - if (current->task_works) { + if (test_thread_flag(TIF_NOTIFY_SIGNAL) || current->task_works) { __set_current_state(TASK_RUNNING); - task_work_run(); + tracehook_notify_signal(); return true; }

return false; }

-static void io_iopoll_queue(struct list_head *again) -{ - struct io_kiocb *req; - - do { - req = list_first_entry(again, struct io_kiocb, iopoll_entry); - list_del(&req->iopoll_entry); - __io_complete_rw(req, -EAGAIN, 0, NULL); - } while (!list_empty(again)); -} - /* * Find and free completed poll iocbs */ @@ -2367,41 +2468,25 @@ static void io_iopoll_complete(struct io_ring_ctx *ctx, unsigned int *nr_events, { struct req_batch rb; struct io_kiocb *req; - LIST_HEAD(again);

/* order with ->result store in io_complete_rw_iopoll() */ smp_rmb();

io_init_req_batch(&rb); while (!list_empty(done)) { - int cflags = 0; - - req = list_first_entry(done, struct io_kiocb, iopoll_entry); - if (READ_ONCE(req->result) == -EAGAIN) { - req->result = 0; - req->iopoll_completed = 0; - list_move_tail(&req->iopoll_entry, &again); - continue; - } - list_del(&req->iopoll_entry); - - if (req->flags & REQ_F_BUFFER_SELECTED) - cflags = io_put_rw_kbuf(req); + req = list_first_entry(done, struct io_kiocb, inflight_entry); + list_del(&req->inflight_entry);

- __io_cqring_fill_event(req, req->result, cflags); + io_fill_cqe_req(req, req->result, io_put_rw_kbuf(req)); (*nr_events)++;

- if (refcount_dec_and_test(&req->refs)) - io_req_free_batch(&rb, req); + if (req_ref_put_and_test(req)) + io_req_free_batch(&rb, req, &ctx->submit_state); }

io_commit_cqring(ctx); - if (ctx->flags & IORING_SETUP_SQPOLL) - io_cqring_ev_posted(ctx); + io_cqring_ev_posted_iopoll(ctx); io_req_free_batch_finish(ctx, &rb); - - if (!list_empty(&again)) - io_iopoll_queue(&again); }

static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, @@ -2410,17 +2495,16 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, struct io_kiocb *req, *tmp; LIST_HEAD(done); bool spin; - int ret;

/* * Only spin for completions if we don't have multiple devices hanging * off our complete list, and we're under the requested amount. */ - spin = !ctx->poll_multi_file && *nr_events < min; + spin = !ctx->poll_multi_queue && *nr_events < min;

- ret = 0; - list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, iopoll_entry) { + list_for_each_entry_safe(req, tmp, &ctx->iopoll_list, inflight_entry) { struct kiocb *kiocb = &req->rw.kiocb; + int ret;

/* * Move completed and retryable entries to our local lists. @@ -2428,50 +2512,27 @@ static int io_do_iopoll(struct io_ring_ctx *ctx, unsigned int *nr_events, * and complete those lists first, if we have entries there. */ if (READ_ONCE(req->iopoll_completed)) { - list_move_tail(&req->iopoll_entry, &done); + list_move_tail(&req->inflight_entry, &done); continue; } if (!list_empty(&done)) break;

ret = kiocb->ki_filp->f_op->iopoll(kiocb, spin); - if (ret < 0) - break; + if (unlikely(ret < 0)) + return ret; + else if (ret) + spin = false;

/* iopoll may have completed current req */ if (READ_ONCE(req->iopoll_completed)) - list_move_tail(&req->iopoll_entry, &done); - - if (ret && spin) - spin = false; - ret = 0; + list_move_tail(&req->inflight_entry, &done); }

if (!list_empty(&done)) io_iopoll_complete(ctx, nr_events, &done);

- return ret; -} - -/* - * Poll for a minimum of 'min' events. Note that if min == 0 we consider that a - * non-spinning poll check - we'll still enter the driver poll loop, but only - * as a non-spinning completion check. - */ -static int io_iopoll_getevents(struct io_ring_ctx *ctx, unsigned int *nr_events, - long min) -{ - while (!list_empty(&ctx->iopoll_list) && !need_resched()) { - int ret; - - ret = io_do_iopoll(ctx, nr_events, min); - if (ret < 0) - return ret; - if (*nr_events >= min) - return 0; - } - - return 1; + return 0; }

/* @@ -2509,7 +2570,7 @@ static void io_iopoll_try_reap_events(struct io_ring_ctx *ctx) static int io_iopoll_check(struct io_ring_ctx *ctx, long min) { unsigned int nr_events = 0; - int iters = 0, ret = 0; + int ret = 0;

/* * We disallow the app entering submit/complete with polling, but we @@ -2517,17 +2578,16 @@ static int io_iopoll_check(struct io_ring_ctx *ctx, long min) * that got punted to a workqueue. */ mutex_lock(&ctx->uring_lock); + /* + * Don't enter poll loop if we already have events pending. + * If we do, we can potentially be spinning for commands that + * already triggered a CQE (eg in error). + */ + if (test_bit(0, &ctx->check_cq_overflow)) + __io_cqring_overflow_flush(ctx, false); + if (io_cqring_events(ctx)) + goto out; do { - /* - * Don't enter poll loop if we already have events pending. - * If we do, we can potentially be spinning for commands that - * already triggered a CQE (eg in error). - */ - if (test_bit(0, &ctx->cq_check_overflow)) - __io_cqring_overflow_flush(ctx, false, NULL, NULL); - if (io_cqring_events(ctx)) - break; - /* * If a submit got punted to a workqueue, we can have the * application entering polling for a command before it gets @@ -2538,18 +2598,21 @@ static int io_iopoll_check(struct io_ring_ctx *ctx, long min) * forever, while the workqueue is stuck trying to acquire the * very same mutex. */ - if (!(++iters & 7)) { + if (list_empty(&ctx->iopoll_list)) { + u32 tail = ctx->cached_cq_tail; + mutex_unlock(&ctx->uring_lock); io_run_task_work(); mutex_lock(&ctx->uring_lock); - } - - ret = io_iopoll_getevents(ctx, &nr_events, min); - if (ret <= 0) - break; - ret = 0; - } while (min && !nr_events && !need_resched());

+ /* some requests don't go through iopoll_list */ + if (tail != ctx->cached_cq_tail || + list_empty(&ctx->iopoll_list)) + break; + } + ret = io_do_iopoll(ctx, &nr_events, min); + } while (!ret && nr_events < min && !need_resched()); +out: mutex_unlock(&ctx->uring_lock); return ret; } @@ -2561,79 +2624,129 @@ static void kiocb_end_write(struct io_kiocb *req) * thread. */ if (req->flags & REQ_F_ISREG) { - struct inode *inode = file_inode(req->file); + struct super_block *sb = file_inode(req->file)->i_sb;

- __sb_writers_acquired(inode->i_sb, SB_FREEZE_WRITE); + __sb_writers_acquired(sb, SB_FREEZE_WRITE); + sb_end_write(sb); } - file_end_write(req->file); -} - -static void io_complete_rw_common(struct kiocb *kiocb, long res, - struct io_comp_state *cs) -{ - struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); - int cflags = 0; - - if (kiocb->ki_flags & IOCB_WRITE) - kiocb_end_write(req); - - if (res != req->result) - req_set_fail_links(req); - if (req->flags & REQ_F_BUFFER_SELECTED) - cflags = io_put_rw_kbuf(req); - __io_req_complete(req, res, cflags, cs); }

#ifdef CONFIG_BLOCK -static bool io_resubmit_prep(struct io_kiocb *req, int error) +static bool io_resubmit_prep(struct io_kiocb *req) { - req_set_fail_links(req); - return false; + struct io_async_rw *rw = req->async_data; + + if (!rw) + return !io_req_prep_async(req); + iov_iter_restore(&rw->iter, &rw->iter_state); + return true; } -#endif

-static bool io_rw_reissue(struct io_kiocb *req, long res) +static bool io_rw_should_reissue(struct io_kiocb *req) { -#ifdef CONFIG_BLOCK umode_t mode = file_inode(req->file)->i_mode; - int ret; + struct io_ring_ctx *ctx = req->ctx;

if (!S_ISBLK(mode) && !S_ISREG(mode)) return false; - if ((res != -EAGAIN && res != -EOPNOTSUPP) || io_wq_current_is_worker()) + if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() && + !(ctx->flags & IORING_SETUP_IOPOLL))) return false; /* * If ref is dying, we might be running poll reap from the exit work. * Don't attempt to reissue from that path, just let it fail with * -EAGAIN. */ - if (percpu_ref_is_dying(&req->ctx->refs)) + if (percpu_ref_is_dying(&ctx->refs)) + return false; + /* + * Play it safe and assume not safe to re-import and reissue if we're + * not in the original thread group (or in task context). + */ + if (!same_thread_group(req->task, current) || !in_task()) return false; + return true; +} +#else +static bool io_resubmit_prep(struct io_kiocb *req) +{ + return false; +} +static bool io_rw_should_reissue(struct io_kiocb *req) +{ + return false; +} +#endif + +static bool __io_complete_rw_common(struct io_kiocb *req, long res) +{ + if (req->rw.kiocb.ki_flags & IOCB_WRITE) { + kiocb_end_write(req); + fsnotify_modify(req->file); + } else { + fsnotify_access(req->file); + } + if (res != req->result) { + if ((res == -EAGAIN || res == -EOPNOTSUPP) && + io_rw_should_reissue(req)) { + req->flags |= REQ_F_REISSUE; + return true; + } + req_set_fail(req); + req->result = res; + } + return false; +}

- ret = io_sq_thread_acquire_mm(req->ctx, req); +static inline int io_fixup_rw_res(struct io_kiocb *req, unsigned res) +{ + struct io_async_rw *io = req->async_data;

- if (io_resubmit_prep(req, ret)) { - refcount_inc(&req->refs); - io_queue_async_work(req); - return true; + /* add previously done IO, if any */ + if (io && io->bytes_done > 0) { + if (res < 0) + res = io->bytes_done; + else + res += io->bytes_done; } + return res; +}

-#endif - return false; +static void io_req_task_complete(struct io_kiocb *req, bool *locked) +{ + unsigned int cflags = io_put_rw_kbuf(req); + int res = req->result; + + if (*locked) { + struct io_ring_ctx *ctx = req->ctx; + struct io_submit_state *state = &ctx->submit_state; + + io_req_complete_state(req, res, cflags); + state->compl_reqs[state->compl_nr++] = req; + if (state->compl_nr == ARRAY_SIZE(state->compl_reqs)) + io_submit_flush_completions(ctx); + } else { + io_req_complete_post(req, res, cflags); + } }

static void __io_complete_rw(struct io_kiocb *req, long res, long res2, - struct io_comp_state *cs) + unsigned int issue_flags) { - if (!io_rw_reissue(req, res)) - io_complete_rw_common(&req->rw.kiocb, res, cs); + if (__io_complete_rw_common(req, res)) + return; + __io_req_complete(req, issue_flags, io_fixup_rw_res(req, res), io_put_rw_kbuf(req)); }

static void io_complete_rw(struct kiocb *kiocb, long res, long res2) { struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);

- __io_complete_rw(req, res, res2, NULL); + if (__io_complete_rw_common(req, res)) + return; + req->result = io_fixup_rw_res(req, res); + req->io_task_work.func = io_req_task_complete; + io_req_task_work_add(req); }

static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2) @@ -2642,12 +2755,15 @@ static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2)

if (kiocb->ki_flags & IOCB_WRITE) kiocb_end_write(req); - - if (res != -EAGAIN && res != req->result) - req_set_fail_links(req); + if (unlikely(res != req->result)) { + if (res == -EAGAIN && io_rw_should_reissue(req)) { + req->flags |= REQ_F_REISSUE; + return; + } + }

WRITE_ONCE(req->result, res); - /* order with io_poll_complete() checking ->result */ + /* order with io_iopoll_complete() checking ->result */ smp_wmb(); WRITE_ONCE(req->iopoll_completed, 1); } @@ -2655,12 +2771,17 @@ static void io_complete_rw_iopoll(struct kiocb *kiocb, long res, long res2) /* * After the iocb has been issued, it's safe to be found on the poll list. * Adding the kiocb to the list AFTER submission ensures that we don't - * find it from a io_iopoll_getevents() thread before the issuer is done + * find it from a io_do_iopoll() thread before the issuer is done * accessing the kiocb cookie. */ static void io_iopoll_req_issued(struct io_kiocb *req) { struct io_ring_ctx *ctx = req->ctx; + const bool in_async = io_wq_current_is_worker(); + + /* workqueue context doesn't hold uring_lock, grab it now */ + if (unlikely(in_async)) + mutex_lock(&ctx->uring_lock);

/* * Track whether we have multiple files in our lists. This will impact @@ -2668,14 +2789,22 @@ static void io_iopoll_req_issued(struct io_kiocb *req) * different devices. */ if (list_empty(&ctx->iopoll_list)) { - ctx->poll_multi_file = false; - } else if (!ctx->poll_multi_file) { + ctx->poll_multi_queue = false; + } else if (!ctx->poll_multi_queue) { struct io_kiocb *list_req; + unsigned int queue_num0, queue_num1;

list_req = list_first_entry(&ctx->iopoll_list, struct io_kiocb, - iopoll_entry); - if (list_req->file != req->file) - ctx->poll_multi_file = true; + inflight_entry); + + if (list_req->file != req->file) { + ctx->poll_multi_queue = true; + } else { + queue_num0 = blk_qc_t_to_queue_num(list_req->rw.kiocb.ki_cookie); + queue_num1 = blk_qc_t_to_queue_num(req->rw.kiocb.ki_cookie); + if (queue_num0 != queue_num1) + ctx->poll_multi_queue = true; + } }

/* @@ -2683,61 +2812,28 @@ static void io_iopoll_req_issued(struct io_kiocb *req) * it to the front so we find it first. */ if (READ_ONCE(req->iopoll_completed)) - list_add(&req->iopoll_entry, &ctx->iopoll_list); + list_add(&req->inflight_entry, &ctx->iopoll_list); else - list_add_tail(&req->iopoll_entry, &ctx->iopoll_list); - - if ((ctx->flags & IORING_SETUP_SQPOLL) && - wq_has_sleeper(&ctx->sq_data->wait)) - wake_up(&ctx->sq_data->wait); -} - -static void __io_state_file_put(struct io_submit_state *state) -{ - if (state->has_refs) - fput_many(state->file, state->has_refs); - state->file = NULL; -} - -static inline void io_state_file_put(struct io_submit_state *state) -{ - if (state->file) - __io_state_file_put(state); -} + list_add_tail(&req->inflight_entry, &ctx->iopoll_list);

-/* - * Get as many references to a file as we have IOs left in this submission, - * assuming most submissions are for one file, or at least that each file - * has more than one submission. - */ -static struct file *__io_file_get(struct io_submit_state *state, int fd) -{ - if (!state) - return fget(fd); + if (unlikely(in_async)) { + /* + * If IORING_SETUP_SQPOLL is enabled, sqes are either handle + * in sq thread task context or in io worker task context. If + * current task context is sq thread, we don't need to check + * whether should wake up sq thread. + */ + if ((ctx->flags & IORING_SETUP_SQPOLL) && + wq_has_sleeper(&ctx->sq_data->wait)) + wake_up(&ctx->sq_data->wait);

- if (state->file) { - if (state->fd == fd) { - state->has_refs--; - return state->file; - } - __io_state_file_put(state); + mutex_unlock(&ctx->uring_lock); } - state->file = fget_many(fd, state->ios_left); - if (!state->file) - return NULL; - - state->fd = fd; - state->has_refs = state->ios_left - 1; - return state->file; }

static bool io_bdev_nowait(struct block_device *bdev) { -#ifdef CONFIG_BLOCK return !bdev || blk_queue_nowait(bdev_get_queue(bdev)); -#else - return true; -#endif }

/* @@ -2745,19 +2841,21 @@ static bool io_bdev_nowait(struct block_device *bdev) * any file. For now, just ensure that anything potentially problematic is done * inline. */ -static bool io_file_supports_async(struct file *file, int rw) +static bool __io_file_supports_nowait(struct file *file, int rw) { umode_t mode = file_inode(file)->i_mode;

if (S_ISBLK(mode)) { - if (io_bdev_nowait(file->f_inode->i_bdev)) + if (IS_ENABLED(CONFIG_BLOCK) && + io_bdev_nowait(I_BDEV(file->f_mapping->host))) return true; return false; } if (S_ISSOCK(mode)) return true; if (S_ISREG(mode)) { - if (io_bdev_nowait(file->f_inode->i_sb->s_bdev) && + if (IS_ENABLED(CONFIG_BLOCK) && + io_bdev_nowait(file->f_inode->i_sb->s_bdev) && file->f_op != &io_uring_fops) return true; return false; @@ -2776,20 +2874,36 @@ static bool io_file_supports_async(struct file *file, int rw) return file->f_op->write_iter != NULL; }

-static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe) +static bool io_file_supports_nowait(struct io_kiocb *req, int rw) +{ + if (rw == READ && (req->flags & REQ_F_NOWAIT_READ)) + return true; + else if (rw == WRITE && (req->flags & REQ_F_NOWAIT_WRITE)) + return true; + + return __io_file_supports_nowait(req->file, rw); +} + +static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, + int rw) { struct io_ring_ctx *ctx = req->ctx; struct kiocb *kiocb = &req->rw.kiocb; + struct file *file = req->file; unsigned ioprio; int ret;

- if (S_ISREG(file_inode(req->file)->i_mode)) + if (!io_req_ffs_set(req) && S_ISREG(file_inode(file)->i_mode)) req->flags |= REQ_F_ISREG;

kiocb->ki_pos = READ_ONCE(sqe->off); - if (kiocb->ki_pos == -1 && !(req->file->f_mode & FMODE_STREAM)) { - req->flags |= REQ_F_CUR_POS; - kiocb->ki_pos = req->file->f_pos; + if (kiocb->ki_pos == -1) { + if (!(file->f_mode & FMODE_STREAM)) { + req->flags |= REQ_F_CUR_POS; + kiocb->ki_pos = file->f_pos; + } else { + kiocb->ki_pos = 0; + } } kiocb->ki_hint = ki_hint_validate(file_write_hint(kiocb->ki_filp)); kiocb->ki_flags = iocb_flags(kiocb->ki_filp); @@ -2797,6 +2911,15 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe) if (unlikely(ret)) return ret;

+ /* + * If the file is marked O_NONBLOCK, still allow retry for it if it + * supports async. Otherwise it's impossible to use O_NONBLOCK files + * reliably. If not, or it IOCB_NOWAIT is set, don't retry. + */ + if ((kiocb->ki_flags & IOCB_NOWAIT) || + ((file->f_flags & O_NONBLOCK) && !io_file_supports_nowait(req, rw))) + req->flags |= REQ_F_NOWAIT; + ioprio = READ_ONCE(sqe->ioprio); if (ioprio) { ret = ioprio_check_cap(ioprio); @@ -2807,10 +2930,6 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe) } else kiocb->ki_ioprio = get_current_ioprio();

- /* don't allow async punt if RWF_NOWAIT was requested */ - if (kiocb->ki_flags & IOCB_NOWAIT) - req->flags |= REQ_F_NOWAIT; - if (ctx->flags & IORING_SETUP_IOPOLL) { if (!(kiocb->ki_flags & IOCB_DIRECT) || !kiocb->ki_filp->f_op->iopoll) @@ -2825,9 +2944,24 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe) kiocb->ki_complete = io_complete_rw; }

+ /* used for fixed read/write too - just read unconditionally */ + req->buf_index = READ_ONCE(sqe->buf_index); + req->imu = NULL; + + if (req->opcode == IORING_OP_READ_FIXED || + req->opcode == IORING_OP_WRITE_FIXED) { + struct io_ring_ctx *ctx = req->ctx; + u16 index; + + if (unlikely(req->buf_index >= ctx->nr_user_bufs)) + return -EFAULT; + index = array_index_nospec(req->buf_index, ctx->nr_user_bufs); + req->imu = ctx->user_bufs[index]; + io_req_set_rsrc_node(req); + } + req->rw.addr = READ_ONCE(sqe->addr); req->rw.len = READ_ONCE(sqe->len); - req->buf_index = READ_ONCE(sqe->buf_index); return 0; }

@@ -2853,48 +2987,49 @@ static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret) }

static void kiocb_done(struct kiocb *kiocb, ssize_t ret, - struct io_comp_state *cs) + unsigned int issue_flags) { struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb); - struct io_async_rw *io = req->async_data; - - /* add previously done IO, if any */ - if (io && io->bytes_done > 0) { - if (ret < 0) - ret = io->bytes_done; - else - ret += io->bytes_done; - }

if (req->flags & REQ_F_CUR_POS) req->file->f_pos = kiocb->ki_pos; - if (ret >= 0 && kiocb->ki_complete == io_complete_rw) - __io_complete_rw(req, ret, 0, cs); + if (ret >= 0 && (kiocb->ki_complete == io_complete_rw)) + __io_complete_rw(req, ret, 0, issue_flags); else io_rw_done(kiocb, ret); + + if (req->flags & REQ_F_REISSUE) { + req->flags &= ~REQ_F_REISSUE; + if (io_resubmit_prep(req)) { + io_req_task_queue_reissue(req); + } else { + unsigned int cflags = io_put_rw_kbuf(req); + struct io_ring_ctx *ctx = req->ctx; + + ret = io_fixup_rw_res(req, ret); + req_set_fail(req); + if (!(issue_flags & IO_URING_F_NONBLOCK)) { + mutex_lock(&ctx->uring_lock); + __io_req_complete(req, issue_flags, ret, cflags); + mutex_unlock(&ctx->uring_lock); + } else { + __io_req_complete(req, issue_flags, ret, cflags); + } + } + } }

-static ssize_t io_import_fixed(struct io_kiocb *req, int rw, - struct iov_iter *iter) +static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter, + struct io_mapped_ubuf *imu) { - struct io_ring_ctx *ctx = req->ctx; size_t len = req->rw.len; - struct io_mapped_ubuf *imu; - u16 index, buf_index = req->buf_index; + u64 buf_end, buf_addr = req->rw.addr; size_t offset; - u64 buf_addr;

- if (unlikely(buf_index >= ctx->nr_user_bufs)) - return -EFAULT; - index = array_index_nospec(buf_index, ctx->nr_user_bufs); - imu = &ctx->user_bufs[index]; - buf_addr = req->rw.addr; - - /* overflow */ - if (buf_addr + len < buf_addr) + if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end))) return -EFAULT; /* not inside the mapped region */ - if (buf_addr < imu->ubuf || buf_addr + len > imu->ubuf + imu->len) + if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end)) return -EFAULT;

/* @@ -2939,7 +3074,14 @@ static ssize_t io_import_fixed(struct io_kiocb *req, int rw, } }

- return len; + return 0; +} + +static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter) +{ + if (WARN_ON_ONCE(!req->imu)) + return -EFAULT; + return __io_import_fixed(req, rw, iter, req->imu); }

static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock) @@ -3080,16 +3222,14 @@ static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov, return __io_iov_buffer_select(req, iov, needs_lock); }

-static ssize_t __io_import_iovec(int rw, struct io_kiocb *req, - struct iovec **iovec, struct iov_iter *iter, - bool needs_lock) +static int io_import_iovec(int rw, struct io_kiocb *req, struct iovec **iovec, + struct iov_iter *iter, bool needs_lock) { void __user *buf = u64_to_user_ptr(req->rw.addr); size_t sqe_len = req->rw.len; + u8 opcode = req->opcode; ssize_t ret; - u8 opcode;

- opcode = req->opcode; if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED) { *iovec = NULL; return io_import_fixed(req, rw, iter); @@ -3114,10 +3254,8 @@ static ssize_t __io_import_iovec(int rw, struct io_kiocb *req,

if (req->flags & REQ_F_BUFFER_SELECT) { ret = io_iov_buffer_select(req, *iovec, needs_lock); - if (!ret) { - ret = (*iovec)->iov_len; - iov_iter_init(iter, rw, *iovec, 1, ret); - } + if (!ret) + iov_iter_init(iter, rw, *iovec, 1, (*iovec)->iov_len); *iovec = NULL; return ret; } @@ -3126,18 +3264,6 @@ static ssize_t __io_import_iovec(int rw, struct io_kiocb *req, req->ctx->compat); }

-static ssize_t io_import_iovec(int rw, struct io_kiocb *req, - struct iovec **iovec, struct iov_iter *iter, - bool needs_lock) -{ - struct io_async_rw *iorw = req->async_data; - - if (!iorw) - return __io_import_iovec(rw, req, iovec, iter, needs_lock); - *iovec = NULL; - return 0; -} - static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb) { return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos; @@ -3230,32 +3356,31 @@ static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec, } }

-static inline int __io_alloc_async_data(struct io_kiocb *req) +static inline int io_alloc_async_data(struct io_kiocb *req) { WARN_ON_ONCE(!io_op_defs[req->opcode].async_size); req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL); return req->async_data == NULL; }

-static int io_alloc_async_data(struct io_kiocb *req) -{ - if (!io_op_defs[req->opcode].needs_async_data) - return 0; - - return __io_alloc_async_data(req); -} - static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec, const struct iovec *fast_iov, struct iov_iter *iter, bool force) { - if (!force && !io_op_defs[req->opcode].needs_async_data) + if (!force && !io_op_defs[req->opcode].needs_async_setup) return 0; if (!req->async_data) { - if (__io_alloc_async_data(req)) + struct io_async_rw *iorw; + + if (io_alloc_async_data(req)) { + kfree(iovec); return -ENOMEM; + }

io_req_map_rw(req, iovec, fast_iov, iter); + iorw = req->async_data; + /* we've copied and mapped the iter, ensure state is saved */ + iov_iter_save_state(&iorw->iter, &iorw->iter_state); } return 0; } @@ -3264,9 +3389,9 @@ static inline int io_rw_prep_async(struct io_kiocb *req, int rw) { struct io_async_rw *iorw = req->async_data; struct iovec *iov = iorw->fast_iov; - ssize_t ret; + int ret;

- ret = __io_import_iovec(rw, req, &iov, &iorw->iter, false); + ret = io_import_iovec(rw, req, &iov, &iorw->iter, false); if (unlikely(ret < 0)) return ret;

@@ -3274,24 +3399,15 @@ static inline int io_rw_prep_async(struct io_kiocb *req, int rw) iorw->free_iovec = iov; if (iov) req->flags |= REQ_F_NEED_CLEANUP; + iov_iter_save_state(&iorw->iter, &iorw->iter_state); return 0; }

static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - ssize_t ret; - - ret = io_prep_rw(req, sqe); - if (ret) - return ret; - if (unlikely(!(req->file->f_mode & FMODE_READ))) return -EBADF; - - /* either don't need iovec imported or already have it */ - if (!req->async_data) - return 0; - return io_rw_prep_async(req, READ); + return io_prep_rw(req, sqe, READ); }

/* @@ -3310,7 +3426,6 @@ static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode, struct wait_page_queue *wpq; struct io_kiocb *req = wait->private; struct wait_page_key *key = arg; - int ret;

wpq = container_of(wait, struct wait_page_queue, wait);

@@ -3319,22 +3434,7 @@ static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,

req->rw.kiocb.ki_flags &= ~IOCB_WAITQ; list_del_init(&wait->entry); - - init_task_work(&req->task_work, io_req_task_submit); - percpu_ref_get(&req->ctx->refs); - - /* submit ref gets dropped, acquire a new one */ - refcount_inc(&req->refs); - ret = io_req_task_work_add(req, true); - if (unlikely(ret)) { - struct task_struct *tsk; - - /* queue just for cancelation */ - init_task_work(&req->task_work, io_req_task_cancel); - tsk = io_wq_get_task(req->ctx->io_wq); - task_work_add(tsk, &req->task_work, TWA_NONE); - wake_up_process(tsk); - } + io_req_task_queue(req); return 1; }

@@ -3381,7 +3481,7 @@ static bool io_rw_should_retry(struct io_kiocb *req) return true; }

-static int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter) +static inline int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter) { if (req->file->f_op->read_iter) return call_read_iter(req->file, &req->rw.kiocb, iter); @@ -3391,27 +3491,40 @@ static int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter) return -EINVAL; }

-static int io_read(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static bool need_read_all(struct io_kiocb *req) +{ + return req->flags & REQ_F_ISREG || + S_ISBLK(file_inode(req->file)->i_mode); +} + +static int io_read(struct io_kiocb *req, unsigned int issue_flags) { struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; struct kiocb *kiocb = &req->rw.kiocb; struct iov_iter __iter, *iter = &__iter; - struct iov_iter iter_cp; struct io_async_rw *rw = req->async_data; - ssize_t io_size, ret, ret2; - bool no_async; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; + struct iov_iter_state __state, *state; + ssize_t ret, ret2;

- if (rw) + if (rw) { iter = &rw->iter; - - ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock); - if (ret < 0) - return ret; - iter_cp = *iter; - io_size = iov_iter_count(iter); - req->result = io_size; - ret = 0; + state = &rw->iter_state; + /* + * We come here from an earlier attempt, restore our state to + * match in case it doesn't. It's cheap enough that we don't + * need to make this conditional. + */ + iov_iter_restore(iter, state); + iovec = NULL; + } else { + ret = io_import_iovec(READ, req, &iovec, iter, !force_nonblock); + if (ret < 0) + return ret; + state = &__state; + iov_iter_save_state(iter, state); + } + req->result = iov_iter_count(iter);

/* Ensure we clear previously set non-block flag */ if (!force_nonblock) @@ -3419,127 +3532,130 @@ static int io_read(struct io_kiocb *req, bool force_nonblock, else kiocb->ki_flags |= IOCB_NOWAIT;

- /* If the file doesn't support async, just async punt */ - no_async = force_nonblock && !io_file_supports_async(req->file, READ); - if (no_async) - goto copy_iov; + if (force_nonblock && !io_file_supports_nowait(req, READ)) { + ret = io_setup_async_rw(req, iovec, inline_vecs, iter, true); + return ret ?: -EAGAIN; + }

- ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), io_size); - if (unlikely(ret)) - goto out_free; + ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), req->result); + if (unlikely(ret)) { + kfree(iovec); + return ret; + }

ret = io_iter_do_read(req, iter);

- if (!ret) { - goto done; - } else if (ret == -EIOCBQUEUED) { - ret = 0; - goto out_free; - } else if (ret == -EAGAIN) { + if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) { + req->flags &= ~REQ_F_REISSUE; /* IOPOLL retry should happen for io-wq threads */ if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL)) goto done; - /* no retry on NONBLOCK marked file */ - if (req->file->f_flags & O_NONBLOCK) + /* no retry on NONBLOCK nor RWF_NOWAIT */ + if (req->flags & REQ_F_NOWAIT) goto done; - /* some cases will consume bytes even on error returns */ - *iter = iter_cp; ret = 0; - goto copy_iov; - } else if (ret < 0) { - /* make sure -ERESTARTSYS -> -EINTR is done */ + } else if (ret == -EIOCBQUEUED) { + goto out_free; + } else if (ret <= 0 || ret == req->result || !force_nonblock || + (req->flags & REQ_F_NOWAIT) || !need_read_all(req)) { + /* read all, failed, already did sync or don't want to retry */ goto done; }

- /* read it all, or we did blocking attempt. no retry. */ - if (!iov_iter_count(iter) || !force_nonblock || - (req->file->f_flags & O_NONBLOCK) || !(req->flags & REQ_F_ISREG)) - goto done; + /* + * Don't depend on the iter state matching what was consumed, or being + * untouched in case of error. Restore it and we'll advance it + * manually if we need to. + */ + iov_iter_restore(iter, state);

- io_size -= ret; -copy_iov: ret2 = io_setup_async_rw(req, iovec, inline_vecs, iter, true); - if (ret2) { - ret = ret2; - goto out_free; - } - if (no_async) - return -EAGAIN; - rw = req->async_data; - /* it's copied and will be cleaned with ->io */ - iovec = NULL; - /* now use our persistent iterator, if we aren't already */ - iter = &rw->iter; -retry: - rw->bytes_done += ret; - /* if we can retry, do so with the callbacks armed */ - if (!io_rw_should_retry(req)) { - kiocb->ki_flags &= ~IOCB_WAITQ; - return -EAGAIN; - } + if (ret2) + return ret2;

+ iovec = NULL; + rw = req->async_data; /* - * Now retry read with the IOCB_WAITQ parts set in the iocb. If we - * get -EIOCBQUEUED, then we'll get a notification when the desired - * page gets unlocked. We can also get a partial read here, and if we - * do, then just retry at the new offset. + * Now use our persistent iterator and state, if we aren't already. + * We've restored and mapped the iter to match. */ - ret = io_iter_do_read(req, iter); - if (ret == -EIOCBQUEUED) { - ret = 0; - goto out_free; - } else if (ret > 0 && ret < io_size) { + if (iter != &rw->iter) { + iter = &rw->iter; + state = &rw->iter_state; + } + + do { + /* + * We end up here because of a partial read, either from + * above or inside this loop. Advance the iter by the bytes + * that were consumed. + */ + iov_iter_advance(iter, ret); + if (!iov_iter_count(iter)) + break; + rw->bytes_done += ret; + iov_iter_save_state(iter, state); + + /* if we can retry, do so with the callbacks armed */ + if (!io_rw_should_retry(req)) { + kiocb->ki_flags &= ~IOCB_WAITQ; + return -EAGAIN; + } + + req->result = iov_iter_count(iter); + /* + * Now retry read with the IOCB_WAITQ parts set in the iocb. If + * we get -EIOCBQUEUED, then we'll get a notification when the + * desired page gets unlocked. We can also get a partial read + * here, and if we do, then just retry at the new offset. + */ + ret = io_iter_do_read(req, iter); + if (ret == -EIOCBQUEUED) + return 0; /* we got some bytes, but not all. retry. */ kiocb->ki_flags &= ~IOCB_WAITQ; - goto retry; - } + iov_iter_restore(iter, state); + } while (ret > 0); done: - kiocb_done(kiocb, ret, cs); - ret = 0; + kiocb_done(kiocb, ret, issue_flags); out_free: - /* it's reportedly faster than delegating the null check to kfree() */ + /* it's faster to check here then delegate to kfree */ if (iovec) kfree(iovec); - return ret; + return 0; }

static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - ssize_t ret; - - ret = io_prep_rw(req, sqe); - if (ret) - return ret; - if (unlikely(!(req->file->f_mode & FMODE_WRITE))) return -EBADF; - - /* either don't need iovec imported or already have it */ - if (!req->async_data) - return 0; - return io_rw_prep_async(req, WRITE); + return io_prep_rw(req, sqe, WRITE); }

-static int io_write(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_write(struct io_kiocb *req, unsigned int issue_flags) { struct iovec inline_vecs[UIO_FASTIOV], *iovec = inline_vecs; struct kiocb *kiocb = &req->rw.kiocb; struct iov_iter __iter, *iter = &__iter; - struct iov_iter iter_cp; struct io_async_rw *rw = req->async_data; - ssize_t ret, ret2, io_size; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; + struct iov_iter_state __state, *state; + ssize_t ret, ret2;

- if (rw) + if (rw) { iter = &rw->iter; - - ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock); - if (ret < 0) - return ret; - iter_cp = *iter; - io_size = iov_iter_count(iter); - req->result = io_size; + state = &rw->iter_state; + iov_iter_restore(iter, state); + iovec = NULL; + } else { + ret = io_import_iovec(WRITE, req, &iovec, iter, !force_nonblock); + if (ret < 0) + return ret; + state = &__state; + iov_iter_save_state(iter, state); + } + req->result = iov_iter_count(iter);

/* Ensure we clear previously set non-block flag */ if (!force_nonblock) @@ -3548,7 +3664,7 @@ static int io_write(struct io_kiocb *req, bool force_nonblock, kiocb->ki_flags |= IOCB_NOWAIT;

/* If the file doesn't support async, just async punt */ - if (force_nonblock && !io_file_supports_async(req->file, WRITE)) + if (force_nonblock && !io_file_supports_nowait(req, WRITE)) goto copy_iov;

/* file path doesn't support NOWAIT for non-direct_IO */ @@ -3556,7 +3672,7 @@ static int io_write(struct io_kiocb *req, bool force_nonblock, (req->flags & REQ_F_ISREG)) goto copy_iov;

- ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), io_size); + ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), req->result); if (unlikely(ret)) goto out_free;

@@ -3581,28 +3697,36 @@ static int io_write(struct io_kiocb *req, bool force_nonblock, else ret2 = -EINVAL;

+ if (req->flags & REQ_F_REISSUE) { + req->flags &= ~REQ_F_REISSUE; + ret2 = -EAGAIN; + } + /* * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just * retry them without IOCB_NOWAIT. */ if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT)) ret2 = -EAGAIN; - /* no retry on NONBLOCK marked file */ - if (ret2 == -EAGAIN && (req->file->f_flags & O_NONBLOCK)) + /* no retry on NONBLOCK nor RWF_NOWAIT */ + if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT)) goto done; if (!force_nonblock || ret2 != -EAGAIN) { /* IOPOLL retry should happen for io-wq threads */ if ((req->ctx->flags & IORING_SETUP_IOPOLL) && ret2 == -EAGAIN) goto copy_iov; done: - kiocb_done(kiocb, ret2, cs); + kiocb_done(kiocb, ret2, issue_flags); } else { copy_iov: - /* some cases will consume bytes even on error returns */ - *iter = iter_cp; + iov_iter_restore(iter, state); ret = io_setup_async_rw(req, iovec, inline_vecs, iter, false); - if (!ret) + if (!ret) { + if (kiocb->ki_flags & IOCB_WRITE) + kiocb_end_write(req); return -EAGAIN; + } + return ret; } out_free: /* it's reportedly faster than delegating the null check to kfree() */ @@ -3611,37 +3735,160 @@ static int io_write(struct io_kiocb *req, bool force_nonblock, return ret; }

-static int __io_splice_prep(struct io_kiocb *req, +static int io_renameat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - struct io_splice* sp = &req->splice; - unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL; + struct io_rename *ren = &req->rename; + const char __user *oldf, *newf;

if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; + if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in) + return -EINVAL; + if (unlikely(req->flags & REQ_F_FIXED_FILE)) + return -EBADF;

- sp->file_in = NULL; - sp->len = READ_ONCE(sqe->len); - sp->flags = READ_ONCE(sqe->splice_flags); + ren->old_dfd = READ_ONCE(sqe->fd); + oldf = u64_to_user_ptr(READ_ONCE(sqe->addr)); + newf = u64_to_user_ptr(READ_ONCE(sqe->addr2)); + ren->new_dfd = READ_ONCE(sqe->len); + ren->flags = READ_ONCE(sqe->rename_flags);

- if (unlikely(sp->flags & ~valid_flags)) - return -EINVAL; + ren->oldpath = getname(oldf); + if (IS_ERR(ren->oldpath)) + return PTR_ERR(ren->oldpath);

- sp->file_in = io_file_get(NULL, req, READ_ONCE(sqe->splice_fd_in), - (sp->flags & SPLICE_F_FD_IN_FIXED)); - if (!sp->file_in) + ren->newpath = getname(newf); + if (IS_ERR(ren->newpath)) { + putname(ren->oldpath); + return PTR_ERR(ren->newpath); + } + + req->flags |= REQ_F_NEED_CLEANUP; + return 0; +} + +static int io_renameat(struct io_kiocb *req, unsigned int issue_flags) +{ + struct io_rename *ren = &req->rename; + int ret; + + if (issue_flags & IO_URING_F_NONBLOCK) + return -EAGAIN; + + ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd, + ren->newpath, ren->flags); + + req->flags &= ~REQ_F_NEED_CLEANUP; + if (ret < 0) + req_set_fail(req); + io_req_complete(req, ret); + return 0; +} + +static int io_unlinkat_prep(struct io_kiocb *req, + const struct io_uring_sqe *sqe) +{ + struct io_unlink *un = &req->unlink; + const char __user *fname; + + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; + if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index || + sqe->splice_fd_in) + return -EINVAL; + if (unlikely(req->flags & REQ_F_FIXED_FILE)) return -EBADF; + + un->dfd = READ_ONCE(sqe->fd); + + un->flags = READ_ONCE(sqe->unlink_flags); + if (un->flags & ~AT_REMOVEDIR) + return -EINVAL; + + fname = u64_to_user_ptr(READ_ONCE(sqe->addr)); + un->filename = getname(fname); + if (IS_ERR(un->filename)) + return PTR_ERR(un->filename); + req->flags |= REQ_F_NEED_CLEANUP; + return 0; +}

- if (!S_ISREG(file_inode(sp->file_in)->i_mode)) { - /* - * Splice operation will be punted aync, and here need to - * modify io_wq_work.flags, so initialize io_wq_work firstly. - */ - io_req_init_async(req); - req->work.flags |= IO_WQ_WORK_UNBOUND; - } +static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags) +{ + struct io_unlink *un = &req->unlink; + int ret; + + if (issue_flags & IO_URING_F_NONBLOCK) + return -EAGAIN; + + if (un->flags & AT_REMOVEDIR) + ret = do_rmdir(un->dfd, un->filename); + else + ret = do_unlinkat(un->dfd, un->filename); + + req->flags &= ~REQ_F_NEED_CLEANUP; + if (ret < 0) + req_set_fail(req); + io_req_complete(req, ret); + return 0; +} + +static int io_shutdown_prep(struct io_kiocb *req, + const struct io_uring_sqe *sqe) +{ +#if defined(CONFIG_NET) + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; + if (unlikely(sqe->ioprio || sqe->off || sqe->addr || sqe->rw_flags || + sqe->buf_index || sqe->splice_fd_in)) + return -EINVAL; + + req->shutdown.how = READ_ONCE(sqe->len); + return 0; +#else + return -EOPNOTSUPP; +#endif +} + +static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags) +{ +#if defined(CONFIG_NET) + struct socket *sock; + int ret; + + if (issue_flags & IO_URING_F_NONBLOCK) + return -EAGAIN; + + sock = sock_from_file(req->file, &ret); + if (unlikely(!sock)) + return ret; + + ret = __sys_shutdown_sock(sock, req->shutdown.how); + if (ret < 0) + req_set_fail(req); + io_req_complete(req, ret); + return 0; +#else + return -EOPNOTSUPP; +#endif +} + +static int __io_splice_prep(struct io_kiocb *req, + const struct io_uring_sqe *sqe) +{ + struct io_splice *sp = &req->splice; + unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;

+ if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; + + sp->len = READ_ONCE(sqe->len); + sp->flags = READ_ONCE(sqe->splice_flags); + if (unlikely(sp->flags & ~valid_flags)) + return -EINVAL; + sp->splice_fd_in = READ_ONCE(sqe->splice_fd_in); return 0; }

@@ -3653,60 +3900,75 @@ static int io_tee_prep(struct io_kiocb *req, return __io_splice_prep(req, sqe); }

-static int io_tee(struct io_kiocb *req, bool force_nonblock) +static int io_tee(struct io_kiocb *req, unsigned int issue_flags) { struct io_splice *sp = &req->splice; - struct file *in = sp->file_in; struct file *out = sp->file_out; unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED; + struct file *in; long ret = 0;

- if (force_nonblock) + if (issue_flags & IO_URING_F_NONBLOCK) return -EAGAIN; + + in = io_file_get(req->ctx, req, sp->splice_fd_in, + (sp->flags & SPLICE_F_FD_IN_FIXED)); + if (!in) { + ret = -EBADF; + goto done; + } + if (sp->len) ret = do_tee(in, out, sp->len, flags);

- io_put_file(req, in, (sp->flags & SPLICE_F_FD_IN_FIXED)); - req->flags &= ~REQ_F_NEED_CLEANUP; - + if (!(sp->flags & SPLICE_F_FD_IN_FIXED)) + io_put_file(in); +done: if (ret != sp->len) - req_set_fail_links(req); + req_set_fail(req); io_req_complete(req, ret); return 0; }

static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - struct io_splice* sp = &req->splice; + struct io_splice *sp = &req->splice;

sp->off_in = READ_ONCE(sqe->splice_off_in); sp->off_out = READ_ONCE(sqe->off); return __io_splice_prep(req, sqe); }

-static int io_splice(struct io_kiocb *req, bool force_nonblock) +static int io_splice(struct io_kiocb *req, unsigned int issue_flags) { struct io_splice *sp = &req->splice; - struct file *in = sp->file_in; struct file *out = sp->file_out; unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED; loff_t *poff_in, *poff_out; + struct file *in; long ret = 0;

- if (force_nonblock) + if (issue_flags & IO_URING_F_NONBLOCK) return -EAGAIN;

+ in = io_file_get(req->ctx, req, sp->splice_fd_in, + (sp->flags & SPLICE_F_FD_IN_FIXED)); + if (!in) { + ret = -EBADF; + goto done; + } + poff_in = (sp->off_in == -1) ? NULL : &sp->off_in; poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;

if (sp->len) ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);

- io_put_file(req, in, (sp->flags & SPLICE_F_FD_IN_FIXED)); - req->flags &= ~REQ_F_NEED_CLEANUP; - + if (!(sp->flags & SPLICE_F_FD_IN_FIXED)) + io_put_file(in); +done: if (ret != sp->len) - req_set_fail_links(req); + req_set_fail(req); io_req_complete(req, ret); return 0; } @@ -3714,24 +3976,21 @@ static int io_splice(struct io_kiocb *req, bool force_nonblock) /* * IORING_OP_NOP just posts a completion event, nothing else. */ -static int io_nop(struct io_kiocb *req, struct io_comp_state *cs) +static int io_nop(struct io_kiocb *req, unsigned int issue_flags) { struct io_ring_ctx *ctx = req->ctx;

if (unlikely(ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL;

- __io_req_complete(req, 0, 0, cs); + __io_req_complete(req, issue_flags, 0, 0); return 0; }

-static int io_prep_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe) +static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_ring_ctx *ctx = req->ctx;

- if (!req->file) - return -EBADF; - if (unlikely(ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index || @@ -3747,20 +4006,20 @@ static int io_prep_fsync(struct io_kiocb *req, const struct io_uring_sqe *sqe) return 0; }

-static int io_fsync(struct io_kiocb *req, bool force_nonblock) +static int io_fsync(struct io_kiocb *req, unsigned int issue_flags) { loff_t end = req->sync.off + req->sync.len; int ret;

/* fsync always requires a blocking context */ - if (force_nonblock) + if (issue_flags & IO_URING_F_NONBLOCK) return -EAGAIN;

ret = vfs_fsync_range(req->file, req->sync.off, end > 0 ? end : LLONG_MAX, req->sync.flags & IORING_FSYNC_DATASYNC); if (ret < 0) - req_set_fail_links(req); + req_set_fail(req); io_req_complete(req, ret); return 0; } @@ -3780,17 +4039,19 @@ static int io_fallocate_prep(struct io_kiocb *req, return 0; }

-static int io_fallocate(struct io_kiocb *req, bool force_nonblock) +static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags) { int ret;

/* fallocate always requiring blocking context */ - if (force_nonblock) + if (issue_flags & IO_URING_F_NONBLOCK) return -EAGAIN; ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off, req->sync.len); if (ret < 0) - req_set_fail_links(req); + req_set_fail(req); + else + fsnotify_modify(req->file); io_req_complete(req, ret); return 0; } @@ -3800,7 +4061,9 @@ static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe const char __user *fname; int ret;

- if (unlikely(sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)) + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; + if (unlikely(sqe->ioprio || sqe->buf_index)) return -EINVAL; if (unlikely(req->flags & REQ_F_FIXED_FILE)) return -EBADF; @@ -3817,20 +4080,21 @@ static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe req->open.filename = NULL; return ret; } + + req->open.file_slot = READ_ONCE(sqe->file_index); + if (req->open.file_slot && (req->open.how.flags & O_CLOEXEC)) + return -EINVAL; + req->open.nofile = rlimit(RLIMIT_NOFILE); - req->open.ignore_nonblock = false; req->flags |= REQ_F_NEED_CLEANUP; return 0; }

static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - u64 flags, mode; + u64 mode = READ_ONCE(sqe->len); + u64 flags = READ_ONCE(sqe->open_flags);

- if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) - return -EINVAL; - mode = READ_ONCE(sqe->len); - flags = READ_ONCE(sqe->open_flags); req->open.how = build_open_how(flags, mode); return __io_openat_prep(req, sqe); } @@ -3841,8 +4105,6 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) size_t len; int ret;

- if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) - return -EINVAL; how = u64_to_user_ptr(READ_ONCE(sqe->addr2)); len = READ_ONCE(sqe->len); if (len < OPEN_HOW_SIZE_VER0) @@ -3856,58 +4118,75 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return __io_openat_prep(req, sqe); }

-static int io_openat2(struct io_kiocb *req, bool force_nonblock) +static int io_openat2(struct io_kiocb *req, unsigned int issue_flags) { struct open_flags op; struct file *file; + bool resolve_nonblock, nonblock_set; + bool fixed = !!req->open.file_slot; int ret;

- if (force_nonblock && !req->open.ignore_nonblock) - return -EAGAIN; - ret = build_open_flags(&req->open.how, &op); if (ret) goto err; + nonblock_set = op.open_flag & O_NONBLOCK; + resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED; + if (issue_flags & IO_URING_F_NONBLOCK) { + /* + * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open, + * it'll always -EAGAIN + */ + if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE)) + return -EAGAIN; + op.lookup_flags |= LOOKUP_CACHED; + op.open_flag |= O_NONBLOCK; + }

- ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile); - if (ret < 0) - goto err; + if (!fixed) { + ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile); + if (ret < 0) + goto err; + }

file = do_filp_open(req->open.dfd, req->open.filename, &op); if (IS_ERR(file)) { - put_unused_fd(ret); - ret = PTR_ERR(file); /* - * A work-around to ensure that /proc/self works that way - * that it should - if we get -EOPNOTSUPP back, then assume - * that proc_self_get_link() failed us because we're in async - * context. We should be safe to retry this from the task - * itself with force_nonblock == false set, as it should not - * block on lookup. Would be nice to know this upfront and - * avoid the async dance, but doesn't seem feasible. + * We could hang on to this 'fd' on retrying, but seems like + * marginal gain for something that is now known to be a slower + * path. So just put it, and we'll get a new one when we retry. */ - if (ret == -EOPNOTSUPP && io_wq_current_is_worker()) { - req->open.ignore_nonblock = true; - refcount_inc(&req->refs); - io_req_task_queue(req); - return 0; - } - } else { - fsnotify_open(file); - fd_install(ret, file); + if (!fixed) + put_unused_fd(ret); + + ret = PTR_ERR(file); + /* only retry if RESOLVE_CACHED wasn't already set by application */ + if (ret == -EAGAIN && + (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK))) + return -EAGAIN; + goto err; } + + if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set) + file->f_flags &= ~O_NONBLOCK; + fsnotify_open(file); + + if (!fixed) + fd_install(ret, file); + else + ret = io_install_fixed_file(req, file, issue_flags, + req->open.file_slot - 1); err: putname(req->open.filename); req->flags &= ~REQ_F_NEED_CLEANUP; if (ret < 0) - req_set_fail_links(req); - io_req_complete(req, ret); + req_set_fail(req); + __io_req_complete(req, issue_flags, ret, 0); return 0; }

-static int io_openat(struct io_kiocb *req, bool force_nonblock) +static int io_openat(struct io_kiocb *req, unsigned int issue_flags) { - return io_openat2(req, force_nonblock); + return io_openat2(req, issue_flags); }

static int io_remove_buffers_prep(struct io_kiocb *req, @@ -3948,6 +4227,7 @@ static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf, kfree(nxt); if (++i == nbufs) return i; + cond_resched(); } i++; kfree(buf); @@ -3956,13 +4236,13 @@ static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf, return i; }

-static int io_remove_buffers(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags) { struct io_provide_buf *p = &req->pbuf; struct io_ring_ctx *ctx = req->ctx; struct io_buffer *head; int ret = 0; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;

io_ring_submit_lock(ctx, !force_nonblock);

@@ -3973,16 +4253,11 @@ static int io_remove_buffers(struct io_kiocb *req, bool force_nonblock, if (head) ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs); if (ret < 0) - req_set_fail_links(req); + req_set_fail(req);

- /* need to hold the lock to complete IOPOLL requests */ - if (ctx->flags & IORING_SETUP_IOPOLL) { - __io_req_complete(req, ret, 0, cs); - io_ring_submit_unlock(ctx, !force_nonblock); - } else { - io_ring_submit_unlock(ctx, !force_nonblock); - __io_req_complete(req, ret, 0, cs); - } + /* complete before unlock, IOPOLL may need the lock */ + __io_req_complete(req, issue_flags, ret, 0); + io_ring_submit_unlock(ctx, !force_nonblock); return 0; }

@@ -4049,13 +4324,13 @@ static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head) return i ? i : -ENOMEM; }

-static int io_provide_buffers(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags) { struct io_provide_buf *p = &req->pbuf; struct io_ring_ctx *ctx = req->ctx; struct io_buffer *head, *list; int ret = 0; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;

io_ring_submit_lock(ctx, !force_nonblock);

@@ -4065,21 +4340,16 @@ static int io_provide_buffers(struct io_kiocb *req, bool force_nonblock,

ret = io_add_buffers(p, &head); if (ret >= 0 && !list) { - ret = xa_insert(&ctx->io_buffers, p->bgid, head, GFP_KERNEL); + ret = xa_insert(&ctx->io_buffers, p->bgid, head, + GFP_KERNEL_ACCOUNT); if (ret < 0) __io_remove_buffers(ctx, head, p->bgid, -1U); } if (ret < 0) - req_set_fail_links(req); - - /* need to hold the lock to complete IOPOLL requests */ - if (ctx->flags & IORING_SETUP_IOPOLL) { - __io_req_complete(req, ret, 0, cs); - io_ring_submit_unlock(ctx, !force_nonblock); - } else { - io_ring_submit_unlock(ctx, !force_nonblock); - __io_req_complete(req, ret, 0, cs); - } + req_set_fail(req); + /* complete before unlock, IOPOLL may need the lock */ + __io_req_complete(req, issue_flags, ret, 0); + io_ring_submit_unlock(ctx, !force_nonblock); return 0; }

@@ -4089,7 +4359,7 @@ static int io_epoll_ctl_prep(struct io_kiocb *req, #if defined(CONFIG_EPOLL) if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in) return -EINVAL; - if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL))) + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL;

req->epoll.epfd = READ_ONCE(sqe->fd); @@ -4110,20 +4380,20 @@ static int io_epoll_ctl_prep(struct io_kiocb *req, #endif }

-static int io_epoll_ctl(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags) { #if defined(CONFIG_EPOLL) struct io_epoll *ie = &req->epoll; int ret; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;

ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock); if (force_nonblock && ret == -EAGAIN) return -EAGAIN;

if (ret < 0) - req_set_fail_links(req); - __io_req_complete(req, ret, 0, cs); + req_set_fail(req); + __io_req_complete(req, issue_flags, ret, 0); return 0; #else return -EOPNOTSUPP; @@ -4147,18 +4417,18 @@ static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) #endif }

-static int io_madvise(struct io_kiocb *req, bool force_nonblock) +static int io_madvise(struct io_kiocb *req, unsigned int issue_flags) { #if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU) struct io_madvise *ma = &req->madvise; int ret;

- if (force_nonblock) + if (issue_flags & IO_URING_F_NONBLOCK) return -EAGAIN;

ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice); if (ret < 0) - req_set_fail_links(req); + req_set_fail(req); io_req_complete(req, ret); return 0; #else @@ -4179,12 +4449,12 @@ static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return 0; }

-static int io_fadvise(struct io_kiocb *req, bool force_nonblock) +static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags) { struct io_fadvise *fa = &req->fadvise; int ret;

- if (force_nonblock) { + if (issue_flags & IO_URING_F_NONBLOCK) { switch (fa->advice) { case POSIX_FADV_NORMAL: case POSIX_FADV_RANDOM: @@ -4197,14 +4467,14 @@ static int io_fadvise(struct io_kiocb *req, bool force_nonblock)

ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice); if (ret < 0) - req_set_fail_links(req); - io_req_complete(req, ret); + req_set_fail(req); + __io_req_complete(req, issue_flags, ret, 0); return 0; }

static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL))) + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in) return -EINVAL; @@ -4220,89 +4490,96 @@ static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return 0; }

-static int io_statx(struct io_kiocb *req, bool force_nonblock) +static int io_statx(struct io_kiocb *req, unsigned int issue_flags) { struct io_statx *ctx = &req->statx; int ret;

- if (force_nonblock) + if (issue_flags & IO_URING_F_NONBLOCK) return -EAGAIN;

ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask, ctx->buffer);

if (ret < 0) - req_set_fail_links(req); + req_set_fail(req); io_req_complete(req, ret); return 0; }

static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - /* - * If we queue this for async, it must not be cancellable. That would - * leave the 'file' in an undeterminate state, and here need to modify - * io_wq_work.flags, so initialize io_wq_work firstly. - */ - io_req_init_async(req); - - if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; if (sqe->ioprio || sqe->off || sqe->addr || sqe->len || - sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in) + sqe->rw_flags || sqe->buf_index) return -EINVAL; if (req->flags & REQ_F_FIXED_FILE) return -EBADF;

req->close.fd = READ_ONCE(sqe->fd); - if ((req->file && req->file->f_op == &io_uring_fops)) - return -EBADF; + req->close.file_slot = READ_ONCE(sqe->file_index); + if (req->close.file_slot && req->close.fd) + return -EINVAL;

- req->close.put_file = NULL; return 0; }

-static int io_close(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_close(struct io_kiocb *req, unsigned int issue_flags) { + struct files_struct *files = current->files; struct io_close *close = &req->close; - int ret; + struct fdtable *fdt; + struct file *file = NULL; + int ret = -EBADF;

- /* might be already done during nonblock submission */ - if (!close->put_file) { - ret = close_fd_get_file(close->fd, &close->put_file); - if (ret < 0) - return (ret == -ENOENT) ? -EBADF : ret; + if (req->close.file_slot) { + ret = io_close_fixed(req, issue_flags); + goto err; + } + + spin_lock(&files->file_lock); + fdt = files_fdtable(files); + if (close->fd >= fdt->max_fds) { + spin_unlock(&files->file_lock); + goto err; + } + file = fdt->fd[close->fd]; + if (!file || file->f_op == &io_uring_fops) { + spin_unlock(&files->file_lock); + file = NULL; + goto err; }

/* if the file has a flush method, be safe and punt to async */ - if (close->put_file->f_op->flush && force_nonblock) { - /* not safe to cancel at this point */ - req->work.flags |= IO_WQ_WORK_NO_CANCEL; - /* was never set, but play safe */ - req->flags &= ~REQ_F_NOWAIT; - /* avoid grabbing files - we don't need the files */ - req->flags |= REQ_F_NO_FILE_TABLE; + if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) { + spin_unlock(&files->file_lock); return -EAGAIN; }

+ ret = __close_fd_get_file(close->fd, &file); + spin_unlock(&files->file_lock); + if (ret < 0) { + if (ret == -ENOENT) + ret = -EBADF; + goto err; + } + /* No ->flush() or already async, safely close from here */ - ret = filp_close(close->put_file, req->work.identity->files); + ret = filp_close(file, current->files); +err: if (ret < 0) - req_set_fail_links(req); - fput(close->put_file); - close->put_file = NULL; - __io_req_complete(req, ret, 0, cs); + req_set_fail(req); + if (file) + fput(file); + __io_req_complete(req, issue_flags, ret, 0); return 0; }

-static int io_prep_sfr(struct io_kiocb *req, const struct io_uring_sqe *sqe) +static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_ring_ctx *ctx = req->ctx;

- if (!req->file) - return -EBADF; - if (unlikely(ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index || @@ -4315,18 +4592,18 @@ static int io_prep_sfr(struct io_kiocb *req, const struct io_uring_sqe *sqe) return 0; }

-static int io_sync_file_range(struct io_kiocb *req, bool force_nonblock) +static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags) { int ret;

/* sync_file_range always requires a blocking context */ - if (force_nonblock) + if (issue_flags & IO_URING_F_NONBLOCK) return -EAGAIN;

ret = sync_file_range(req->file, req->sync.off, req->sync.len, req->sync.flags); if (ret < 0) - req_set_fail_links(req); + req_set_fail(req); io_req_complete(req, ret); return 0; } @@ -4340,55 +4617,65 @@ static int io_setup_async_msg(struct io_kiocb *req, if (async_msg) return -EAGAIN; if (io_alloc_async_data(req)) { - if (kmsg->iov != kmsg->fast_iov) - kfree(kmsg->iov); + kfree(kmsg->free_iov); return -ENOMEM; } async_msg = req->async_data; req->flags |= REQ_F_NEED_CLEANUP; memcpy(async_msg, kmsg, sizeof(*kmsg)); + if (async_msg->msg.msg_name) + async_msg->msg.msg_name = &async_msg->addr; + /* if were using fast_iov, set it to the new one */ + if (!async_msg->free_iov) + async_msg->msg.msg_iter.iov = async_msg->fast_iov; + return -EAGAIN; }

static int io_sendmsg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg) { - iomsg->iov = iomsg->fast_iov; iomsg->msg.msg_name = &iomsg->addr; + iomsg->free_iov = iomsg->fast_iov; return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg, - req->sr_msg.msg_flags, &iomsg->iov); + req->sr_msg.msg_flags, &iomsg->free_iov); }

-static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +static int io_sendmsg_prep_async(struct io_kiocb *req) { - struct io_async_msghdr *async_msg = req->async_data; - struct io_sr_msg *sr = &req->sr_msg; int ret;

+ ret = io_sendmsg_copy_hdr(req, req->async_data); + if (!ret) + req->flags |= REQ_F_NEED_CLEANUP; + return ret; +} + +static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +{ + struct io_sr_msg *sr = &req->sr_msg; + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; - if (unlikely(sqe->addr2 || sqe->splice_fd_in || sqe->ioprio)) + if (unlikely(sqe->addr2 || sqe->file_index)) + return -EINVAL; + if (unlikely(sqe->addr2 || sqe->file_index || sqe->ioprio)) return -EINVAL;

- sr->msg_flags = READ_ONCE(sqe->msg_flags); sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr)); sr->len = READ_ONCE(sqe->len); + sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL; + if (sr->msg_flags & MSG_DONTWAIT) + req->flags |= REQ_F_NOWAIT;

#ifdef CONFIG_COMPAT if (req->ctx->compat) sr->msg_flags |= MSG_CMSG_COMPAT; #endif - - if (!async_msg || !io_op_defs[req->opcode].needs_async_data) - return 0; - ret = io_sendmsg_copy_hdr(req, async_msg); - if (!ret) - req->flags |= REQ_F_NEED_CLEANUP; - return ret; + return 0; }

-static int io_sendmsg(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags) { struct io_async_msghdr iomsg, *kmsg; struct socket *sock; @@ -4400,46 +4687,37 @@ static int io_sendmsg(struct io_kiocb *req, bool force_nonblock, if (unlikely(!sock)) return ret;

- if (req->async_data) { - kmsg = req->async_data; - kmsg->msg.msg_name = &kmsg->addr; - /* if iov is set, it's allocated already */ - if (!kmsg->iov) - kmsg->iov = kmsg->fast_iov; - kmsg->msg.msg_iter.iov = kmsg->iov; - } else { + kmsg = req->async_data; + if (!kmsg) { ret = io_sendmsg_copy_hdr(req, &iomsg); if (ret) return ret; kmsg = &iomsg; }

- flags = req->sr_msg.msg_flags | MSG_NOSIGNAL; - if (flags & MSG_DONTWAIT) - req->flags |= REQ_F_NOWAIT; - else if (force_nonblock) + flags = req->sr_msg.msg_flags; + if (issue_flags & IO_URING_F_NONBLOCK) flags |= MSG_DONTWAIT; - if (flags & MSG_WAITALL) min_ret = iov_iter_count(&kmsg->msg.msg_iter);

ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags); - if (force_nonblock && ret == -EAGAIN) + if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN) return io_setup_async_msg(req, kmsg); if (ret == -ERESTARTSYS) ret = -EINTR;

- if (kmsg->iov != kmsg->fast_iov) - kfree(kmsg->iov); + /* fast path, check for non-NULL to avoid function call */ + if (kmsg->free_iov) + kfree(kmsg->free_iov); req->flags &= ~REQ_F_NEED_CLEANUP; if (ret < min_ret) - req_set_fail_links(req); - __io_req_complete(req, ret, 0, cs); + req_set_fail(req); + __io_req_complete(req, issue_flags, ret, 0); return 0; }

-static int io_send(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_send(struct io_kiocb *req, unsigned int issue_flags) { struct io_sr_msg *sr = &req->sr_msg; struct msghdr msg; @@ -4462,25 +4740,22 @@ static int io_send(struct io_kiocb *req, bool force_nonblock, msg.msg_controllen = 0; msg.msg_namelen = 0;

- flags = req->sr_msg.msg_flags | MSG_NOSIGNAL; - if (flags & MSG_DONTWAIT) - req->flags |= REQ_F_NOWAIT; - else if (force_nonblock) + flags = req->sr_msg.msg_flags; + if (issue_flags & IO_URING_F_NONBLOCK) flags |= MSG_DONTWAIT; - if (flags & MSG_WAITALL) min_ret = iov_iter_count(&msg.msg_iter);

msg.msg_flags = flags; ret = sock_sendmsg(sock, &msg); - if (force_nonblock && ret == -EAGAIN) + if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN) return -EAGAIN; if (ret == -ERESTARTSYS) ret = -EINTR;

if (ret < min_ret) - req_set_fail_links(req); - __io_req_complete(req, ret, 0, cs); + req_set_fail(req); + __io_req_complete(req, issue_flags, ret, 0); return 0; }

@@ -4500,15 +4775,14 @@ static int __io_recvmsg_copy_hdr(struct io_kiocb *req, if (req->flags & REQ_F_BUFFER_SELECT) { if (iov_len > 1) return -EINVAL; - if (copy_from_user(iomsg->iov, uiov, sizeof(*uiov))) + if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov))) return -EFAULT; - sr->len = iomsg->iov[0].iov_len; - iov_iter_init(&iomsg->msg.msg_iter, READ, iomsg->iov, 1, - sr->len); - iomsg->iov = NULL; + sr->len = iomsg->fast_iov[0].iov_len; + iomsg->free_iov = NULL; } else { + iomsg->free_iov = iomsg->fast_iov; ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV, - &iomsg->iov, &iomsg->msg.msg_iter, + &iomsg->free_iov, &iomsg->msg.msg_iter, false); if (ret > 0) ret = 0; @@ -4521,16 +4795,14 @@ static int __io_recvmsg_copy_hdr(struct io_kiocb *req, static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg) { - struct compat_msghdr __user *msg_compat; struct io_sr_msg *sr = &req->sr_msg; struct compat_iovec __user *uiov; compat_uptr_t ptr; compat_size_t len; int ret;

- msg_compat = (struct compat_msghdr __user *) sr->umsg; - ret = __get_compat_msghdr(&iomsg->msg, msg_compat, &iomsg->uaddr, - &ptr, &len); + ret = __get_compat_msghdr(&iomsg->msg, sr->umsg_compat, &iomsg->uaddr, + &ptr, &len); if (ret) return ret;

@@ -4547,11 +4819,11 @@ static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req, if (clen < 0) return -EINVAL; sr->len = clen; - iomsg->iov[0].iov_len = clen; - iomsg->iov = NULL; + iomsg->free_iov = NULL; } else { + iomsg->free_iov = iomsg->fast_iov; ret = __import_iovec(READ, (struct iovec __user *)uiov, len, - UIO_FASTIOV, &iomsg->iov, + UIO_FASTIOV, &iomsg->free_iov, &iomsg->msg.msg_iter, true); if (ret < 0) return ret; @@ -4565,7 +4837,6 @@ static int io_recvmsg_copy_hdr(struct io_kiocb *req, struct io_async_msghdr *iomsg) { iomsg->msg.msg_name = &iomsg->addr; - iomsg->iov = iomsg->fast_iov;

#ifdef CONFIG_COMPAT if (req->ctx->compat) @@ -4595,38 +4866,42 @@ static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req) return io_put_kbuf(req, req->sr_msg.kbuf); }

-static int io_recvmsg_prep(struct io_kiocb *req, - const struct io_uring_sqe *sqe) +static int io_recvmsg_prep_async(struct io_kiocb *req) { - struct io_async_msghdr *async_msg = req->async_data; - struct io_sr_msg *sr = &req->sr_msg; int ret;

+ ret = io_recvmsg_copy_hdr(req, req->async_data); + if (!ret) + req->flags |= REQ_F_NEED_CLEANUP; + return ret; +} + +static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +{ + struct io_sr_msg *sr = &req->sr_msg; + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; - if (unlikely(sqe->addr2 || sqe->splice_fd_in || sqe->ioprio)) + if (unlikely(sqe->addr2 || sqe->file_index)) + return -EINVAL; + if (unlikely(sqe->addr2 || sqe->file_index || sqe->ioprio)) return -EINVAL;

- sr->msg_flags = READ_ONCE(sqe->msg_flags); sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr)); sr->len = READ_ONCE(sqe->len); sr->bgid = READ_ONCE(sqe->buf_group); + sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL; + if (sr->msg_flags & MSG_DONTWAIT) + req->flags |= REQ_F_NOWAIT;

#ifdef CONFIG_COMPAT if (req->ctx->compat) sr->msg_flags |= MSG_CMSG_COMPAT; #endif - - if (!async_msg || !io_op_defs[req->opcode].needs_async_data) - return 0; - ret = io_recvmsg_copy_hdr(req, async_msg); - if (!ret) - req->flags |= REQ_F_NEED_CLEANUP; - return ret; + return 0; }

-static int io_recvmsg(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags) { struct io_async_msghdr iomsg, *kmsg; struct socket *sock; @@ -4634,19 +4909,14 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock, unsigned flags; int min_ret = 0; int ret, cflags = 0; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;

sock = sock_from_file(req->file, &ret); if (unlikely(!sock)) return ret;

- if (req->async_data) { - kmsg = req->async_data; - kmsg->msg.msg_name = &kmsg->addr; - /* if iov is set, it's allocated already */ - if (!kmsg->iov) - kmsg->iov = kmsg->fast_iov; - kmsg->msg.msg_iter.iov = kmsg->iov; - } else { + kmsg = req->async_data; + if (!kmsg) { ret = io_recvmsg_copy_hdr(req, &iomsg); if (ret) return ret; @@ -4658,16 +4928,14 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock, if (IS_ERR(kbuf)) return PTR_ERR(kbuf); kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr); - iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->iov, + kmsg->fast_iov[0].iov_len = req->sr_msg.len; + iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov, 1, req->sr_msg.len); }

- flags = req->sr_msg.msg_flags | MSG_NOSIGNAL; - if (flags & MSG_DONTWAIT) - req->flags |= REQ_F_NOWAIT; - else if (force_nonblock) + flags = req->sr_msg.msg_flags; + if (force_nonblock) flags |= MSG_DONTWAIT; - if (flags & MSG_WAITALL) min_ret = iov_iter_count(&kmsg->msg.msg_iter);

@@ -4680,17 +4948,17 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock,

if (req->flags & REQ_F_BUFFER_SELECTED) cflags = io_put_recv_kbuf(req); - if (kmsg->iov != kmsg->fast_iov) - kfree(kmsg->iov); + /* fast path, check for non-NULL to avoid function call */ + if (kmsg->free_iov) + kfree(kmsg->free_iov); req->flags &= ~REQ_F_NEED_CLEANUP; if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC)))) - req_set_fail_links(req); - __io_req_complete(req, ret, cflags, cs); + req_set_fail(req); + __io_req_complete(req, issue_flags, ret, cflags); return 0; }

-static int io_recv(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_recv(struct io_kiocb *req, unsigned int issue_flags) { struct io_buffer *kbuf; struct io_sr_msg *sr = &req->sr_msg; @@ -4701,6 +4969,7 @@ static int io_recv(struct io_kiocb *req, bool force_nonblock, unsigned flags; int min_ret = 0; int ret, cflags = 0; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;

sock = sock_from_file(req->file, &ret); if (unlikely(!sock)) @@ -4724,12 +4993,9 @@ static int io_recv(struct io_kiocb *req, bool force_nonblock, msg.msg_iocb = NULL; msg.msg_flags = 0;

- flags = req->sr_msg.msg_flags | MSG_NOSIGNAL; - if (flags & MSG_DONTWAIT) - req->flags |= REQ_F_NOWAIT; - else if (force_nonblock) + flags = req->sr_msg.msg_flags; + if (force_nonblock) flags |= MSG_DONTWAIT; - if (flags & MSG_WAITALL) min_ret = iov_iter_count(&msg.msg_iter);

@@ -4742,8 +5008,8 @@ static int io_recv(struct io_kiocb *req, bool force_nonblock, if (req->flags & REQ_F_BUFFER_SELECTED) cflags = io_put_recv_kbuf(req); if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC)))) - req_set_fail_links(req); - __io_req_complete(req, ret, cflags, cs); + req_set_fail(req); + __io_req_complete(req, issue_flags, ret, cflags); return 0; }

@@ -4751,48 +5017,79 @@ static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_accept *accept = &req->accept;

- if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; - if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->splice_fd_in) + if (sqe->ioprio || sqe->len || sqe->buf_index) return -EINVAL;

accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr)); accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2)); accept->flags = READ_ONCE(sqe->accept_flags); accept->nofile = rlimit(RLIMIT_NOFILE); + + accept->file_slot = READ_ONCE(sqe->file_index); + if (accept->file_slot && (accept->flags & SOCK_CLOEXEC)) + return -EINVAL; + if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK)) + return -EINVAL; + if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK)) + accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK; return 0; }

-static int io_accept(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_accept(struct io_kiocb *req, unsigned int issue_flags) { struct io_accept *accept = &req->accept; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0; - int ret; + bool fixed = !!accept->file_slot; + struct file *file; + int ret, fd;

if (req->file->f_flags & O_NONBLOCK) req->flags |= REQ_F_NOWAIT;

- ret = __sys_accept4_file(req->file, file_flags, accept->addr, - accept->addr_len, accept->flags, - accept->nofile); - if (ret == -EAGAIN && force_nonblock) - return -EAGAIN; - if (ret < 0) { + if (!fixed) { + fd = __get_unused_fd_flags(accept->flags, accept->nofile); + if (unlikely(fd < 0)) + return fd; + } + file = do_accept(req->file, file_flags, accept->addr, accept->addr_len, + accept->flags); + + if (IS_ERR(file)) { + if (!fixed) + put_unused_fd(fd); + ret = PTR_ERR(file); + if (ret == -EAGAIN && force_nonblock) + return -EAGAIN; if (ret == -ERESTARTSYS) ret = -EINTR; - req_set_fail_links(req); + req_set_fail(req); + } else if (!fixed) { + fd_install(fd, file); + ret = fd; + } else { + ret = io_install_fixed_file(req, file, issue_flags, + accept->file_slot - 1); } - __io_req_complete(req, ret, 0, cs); + __io_req_complete(req, issue_flags, ret, 0); return 0; }

+static int io_connect_prep_async(struct io_kiocb *req) +{ + struct io_async_connect *io = req->async_data; + struct io_connect *conn = &req->connect; + + return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address); +} + static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_connect *conn = &req->connect; - struct io_async_connect *io = req->async_data;

- if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in) @@ -4800,20 +5097,15 @@ static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)

conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr)); conn->addr_len = READ_ONCE(sqe->addr2); - - if (!io) - return 0; - - return move_addr_to_kernel(conn->addr, conn->addr_len, - &io->address); + return 0; }

-static int io_connect(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_connect(struct io_kiocb *req, unsigned int issue_flags) { struct io_async_connect __io, *io; unsigned file_flags; int ret; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;

if (req->async_data) { io = req->async_data; @@ -4837,7 +5129,6 @@ static int io_connect(struct io_kiocb *req, bool force_nonblock, ret = -ENOMEM; goto out; } - io = req->async_data; memcpy(req->async_data, &__io, sizeof(__io)); return -EAGAIN; } @@ -4845,248 +5136,352 @@ static int io_connect(struct io_kiocb *req, bool force_nonblock, ret = -EINTR; out: if (ret < 0) - req_set_fail_links(req); - __io_req_complete(req, ret, 0, cs); + req_set_fail(req); + __io_req_complete(req, issue_flags, ret, 0); return 0; } #else /* !CONFIG_NET */ -static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +#define IO_NETOP_FN(op) \ +static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \ +{ \ + return -EOPNOTSUPP; \ +} + +#define IO_NETOP_PREP(op) \ +IO_NETOP_FN(op) \ +static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \ +{ \ + return -EOPNOTSUPP; \ +} \ + +#define IO_NETOP_PREP_ASYNC(op) \ +IO_NETOP_PREP(op) \ +static int io_##op##_prep_async(struct io_kiocb *req) \ +{ \ + return -EOPNOTSUPP; \ +} + +IO_NETOP_PREP_ASYNC(sendmsg); +IO_NETOP_PREP_ASYNC(recvmsg); +IO_NETOP_PREP_ASYNC(connect); +IO_NETOP_PREP(accept); +IO_NETOP_FN(send); +IO_NETOP_FN(recv); +#endif /* CONFIG_NET */ + +struct io_poll_table { + struct poll_table_struct pt; + struct io_kiocb *req; + int nr_entries; + int error; +}; + +#define IO_POLL_CANCEL_FLAG BIT(31) +#define IO_POLL_RETRY_FLAG BIT(30) +#define IO_POLL_REF_MASK GENMASK(29, 0) + +/* + * We usually have 1-2 refs taken, 128 is more than enough and we want to + * maximise the margin between this amount and the moment when it overflows. + */ +#define IO_POLL_REF_BIAS 128 + +static bool io_poll_get_ownership_slowpath(struct io_kiocb *req) { - return -EOPNOTSUPP; + int v; + + /* + * poll_refs are already elevated and we don't have much hope for + * grabbing the ownership. Instead of incrementing set a retry flag + * to notify the loop that there might have been some change. + */ + v = atomic_fetch_or(IO_POLL_RETRY_FLAG, &req->poll_refs); + if (v & IO_POLL_REF_MASK) + return false; + return !(atomic_fetch_inc(&req->poll_refs) & IO_POLL_REF_MASK); }

-static int io_sendmsg(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +/* + * If refs part of ->poll_refs (see IO_POLL_REF_MASK) is 0, it's free. We can + * bump it and acquire ownership. It's disallowed to modify requests while not + * owning it, that prevents from races for enqueueing task_work's and b/w + * arming poll and wakeups. + */ +static inline bool io_poll_get_ownership(struct io_kiocb *req) { - return -EOPNOTSUPP; + if (unlikely(atomic_read(&req->poll_refs) >= IO_POLL_REF_BIAS)) + return io_poll_get_ownership_slowpath(req); + return !(atomic_fetch_inc(&req->poll_refs) & IO_POLL_REF_MASK); }

-static int io_send(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static void io_poll_mark_cancelled(struct io_kiocb *req) { - return -EOPNOTSUPP; + atomic_or(IO_POLL_CANCEL_FLAG, &req->poll_refs); }

-static int io_recvmsg_prep(struct io_kiocb *req, - const struct io_uring_sqe *sqe) +static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req) { - return -EOPNOTSUPP; + /* pure poll stashes this in ->async_data, poll driven retry elsewhere */ + if (req->opcode == IORING_OP_POLL_ADD) + return req->async_data; + return req->apoll->double_poll; }

-static int io_recvmsg(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req) { - return -EOPNOTSUPP; + if (req->opcode == IORING_OP_POLL_ADD) + return &req->poll; + return &req->apoll->poll; }

-static int io_recv(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static void io_poll_req_insert(struct io_kiocb *req) { - return -EOPNOTSUPP; + struct io_ring_ctx *ctx = req->ctx; + struct hlist_head *list; + + list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)]; + hlist_add_head(&req->hash_node, list); }

-static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events, + wait_queue_func_t wake_func) { - return -EOPNOTSUPP; + poll->head = NULL; +#define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP) + /* mask in events that we always want/need */ + poll->events = events | IO_POLL_UNMASK; + INIT_LIST_HEAD(&poll->wait.entry); + init_waitqueue_func_entry(&poll->wait, wake_func); }

-static int io_accept(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static inline void io_poll_remove_entry(struct io_poll_iocb *poll) { - return -EOPNOTSUPP; + struct wait_queue_head *head = smp_load_acquire(&poll->head); + + if (head) { + spin_lock_irq(&head->lock); + list_del_init(&poll->wait.entry); + poll->head = NULL; + spin_unlock_irq(&head->lock); + } }

-static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +static void io_poll_remove_entries(struct io_kiocb *req) { - return -EOPNOTSUPP; + struct io_poll_iocb *poll = io_poll_get_single(req); + struct io_poll_iocb *poll_double = io_poll_get_double(req); + + /* + * While we hold the waitqueue lock and the waitqueue is nonempty, + * wake_up_pollfree() will wait for us. However, taking the waitqueue + * lock in the first place can race with the waitqueue being freed. + * + * We solve this as eventpoll does: by taking advantage of the fact that + * all users of wake_up_pollfree() will RCU-delay the actual free. If + * we enter rcu_read_lock() and see that the pointer to the queue is + * non-NULL, we can then lock it without the memory being freed out from + * under us. + * + * Keep holding rcu_read_lock() as long as we hold the queue lock, in + * case the caller deletes the entry from the queue, leaving it empty. + * In that case, only RCU prevents the queue memory from being freed. + */ + rcu_read_lock(); + io_poll_remove_entry(poll); + if (poll_double) + io_poll_remove_entry(poll_double); + rcu_read_unlock(); }

-static int io_connect(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +/* + * All poll tw should go through this. Checks for poll events, manages + * references, does rewait, etc. + * + * Returns a negative error on failure. >0 when no action require, which is + * either spurious wakeup or multishot CQE is served. 0 when it's done with + * the request, then the mask is stored in req->result. + */ +static int io_poll_check_events(struct io_kiocb *req) { - return -EOPNOTSUPP; -} -#endif /* CONFIG_NET */ + struct io_ring_ctx *ctx = req->ctx; + struct io_poll_iocb *poll = io_poll_get_single(req); + int v;

-struct io_poll_table { - struct poll_table_struct pt; - struct io_kiocb *req; - int nr_entries; - int error; -}; + /* req->task == current here, checking PF_EXITING is safe */ + if (unlikely(req->task->flags & PF_EXITING)) + io_poll_mark_cancelled(req);

-static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll, - __poll_t mask, task_work_func_t func) -{ - bool twa_signal_ok; - int ret; + do { + v = atomic_read(&req->poll_refs);

- /* for instances that support it check for an event match first: */ - if (mask && !(mask & poll->events)) - return 0; + /* tw handler should be the owner, and so have some references */ + if (WARN_ON_ONCE(!(v & IO_POLL_REF_MASK))) + return 0; + if (v & IO_POLL_CANCEL_FLAG) + return -ECANCELED; + /* + * cqe.res contains only events of the first wake up + * and all others are be lost. Redo vfs_poll() to get + * up to date state. + */ + if ((v & IO_POLL_REF_MASK) != 1) + req->result = 0; + if (v & IO_POLL_RETRY_FLAG) { + req->result = 0; + /* + * We won't find new events that came in between + * vfs_poll and the ref put unless we clear the + * flag in advance. + */ + atomic_andnot(IO_POLL_RETRY_FLAG, &req->poll_refs); + v &= ~IO_POLL_RETRY_FLAG; + }

- trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask); + if (!req->result) { + struct poll_table_struct pt = { ._key = poll->events };

- list_del_init(&poll->wait.entry); + req->result = vfs_poll(req->file, &pt) & poll->events; + }

- req->result = mask; - init_task_work(&req->task_work, func); - percpu_ref_get(&req->ctx->refs); + /* multishot, just fill an CQE and proceed */ + if (req->result && !(poll->events & EPOLLONESHOT)) { + __poll_t mask = mangle_poll(req->result & poll->events); + bool filled;

- /* - * If we using the signalfd wait_queue_head for this wakeup, then - * it's not safe to use TWA_SIGNAL as we could be recursing on the - * tsk->sighand->siglock on doing the wakeup. Should not be needed - * either, as the normal wakeup will suffice. - */ - twa_signal_ok = (poll->head != &req->task->sighand->signalfd_wqh); + spin_lock(&ctx->completion_lock); + filled = io_fill_cqe_aux(ctx, req->user_data, mask, + IORING_CQE_F_MORE); + io_commit_cqring(ctx); + spin_unlock(&ctx->completion_lock); + if (unlikely(!filled)) + return -ECANCELED; + io_cqring_ev_posted(ctx); + } else if (req->result) { + return 0; + }

- /* - * If this fails, then the task is exiting. When a task exits, the - * work gets canceled, so just cancel this request as well instead - * of executing it. We can't safely execute it anyway, as we may not - * have the needed state needed for it anyway. - */ - ret = io_req_task_work_add(req, twa_signal_ok); - if (unlikely(ret)) { - struct task_struct *tsk; + /* force the next iteration to vfs_poll() */ + req->result = 0; + + /* + * Release all references, retry if someone tried to restart + * task_work while we were executing it. + */ + } while (atomic_sub_return(v & IO_POLL_REF_MASK, &req->poll_refs) & + IO_POLL_REF_MASK);

- WRITE_ONCE(poll->canceled, true); - tsk = io_wq_get_task(req->ctx->io_wq); - task_work_add(tsk, &req->task_work, TWA_NONE); - wake_up_process(tsk); - } return 1; }

-static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll) - __acquires(&req->ctx->completion_lock) +static void io_poll_task_func(struct io_kiocb *req, bool *locked) { struct io_ring_ctx *ctx = req->ctx; + int ret;

- if (!req->result && !READ_ONCE(poll->canceled)) { - struct poll_table_struct pt = { ._key = poll->events }; - - req->result = vfs_poll(req->file, &pt) & poll->events; - } + ret = io_poll_check_events(req); + if (ret > 0) + return;

- spin_lock_irq(&ctx->completion_lock); - if (!req->result && !READ_ONCE(poll->canceled)) { - add_wait_queue(poll->head, &poll->wait); - return true; + if (!ret) { + req->result = mangle_poll(req->result & req->poll.events); + } else { + req->result = ret; + req_set_fail(req); }

- return false; -} - -static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req) -{ - /* pure poll stashes this in ->async_data, poll driven retry elsewhere */ - if (req->opcode == IORING_OP_POLL_ADD) - return req->async_data; - return req->apoll->double_poll; -} - -static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req) -{ - if (req->opcode == IORING_OP_POLL_ADD) - return &req->poll; - return &req->apoll->poll; + io_poll_remove_entries(req); + spin_lock(&ctx->completion_lock); + hash_del(&req->hash_node); + spin_unlock(&ctx->completion_lock); + io_req_complete_post(req, req->result, 0); }

-static void io_poll_remove_double(struct io_kiocb *req) +static void io_apoll_task_func(struct io_kiocb *req, bool *locked) { - struct io_poll_iocb *poll = io_poll_get_double(req); + struct io_ring_ctx *ctx = req->ctx; + int ret;

- lockdep_assert_held(&req->ctx->completion_lock); + ret = io_poll_check_events(req); + if (ret > 0) + return;

- if (poll && poll->head) { - struct wait_queue_head *head = poll->head; + io_poll_remove_entries(req); + spin_lock(&ctx->completion_lock); + hash_del(&req->hash_node); + spin_unlock(&ctx->completion_lock);

- spin_lock(&head->lock); - list_del_init(&poll->wait.entry); - if (poll->wait.private) - refcount_dec(&req->refs); - poll->head = NULL; - spin_unlock(&head->lock); - } + if (!ret) + io_req_task_submit(req, locked); + else + io_req_complete_failed(req, ret); }

-static void io_poll_complete(struct io_kiocb *req, __poll_t mask, int error) +static void __io_poll_execute(struct io_kiocb *req, int mask) { - struct io_ring_ctx *ctx = req->ctx; + req->result = mask; + if (req->opcode == IORING_OP_POLL_ADD) + req->io_task_work.func = io_poll_task_func; + else + req->io_task_work.func = io_apoll_task_func;

- io_poll_remove_double(req); - req->poll.done = true; - io_cqring_fill_event(req, error ? error : mangle_poll(mask)); - io_commit_cqring(ctx); + trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask); + io_req_task_work_add(req); }

-static void io_poll_task_func(struct callback_head *cb) +static inline void io_poll_execute(struct io_kiocb *req, int res) { - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); - struct io_ring_ctx *ctx = req->ctx; - struct io_kiocb *nxt; - - if (io_poll_rewait(req, &req->poll)) { - spin_unlock_irq(&ctx->completion_lock); - } else { - hash_del(&req->hash_node); - io_poll_complete(req, req->result, 0); - spin_unlock_irq(&ctx->completion_lock); - - nxt = io_put_req_find_next(req); - io_cqring_ev_posted(ctx); - if (nxt) - __io_req_task_submit(nxt); - } + if (io_poll_get_ownership(req)) + __io_poll_execute(req, res); +}

- percpu_ref_put(&ctx->refs); +static void io_poll_cancel_req(struct io_kiocb *req) +{ + io_poll_mark_cancelled(req); + /* kick tw, which should complete the request */ + io_poll_execute(req, 0); }

-static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode, - int sync, void *key) +static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, + void *key) { struct io_kiocb *req = wait->private; - struct io_poll_iocb *poll = io_poll_get_single(req); + struct io_poll_iocb *poll = container_of(wait, struct io_poll_iocb, + wait); __poll_t mask = key_to_poll(key);

- /* for instances that support it check for an event match first: */ - if (mask && !(mask & poll->events)) - return 0; + if (unlikely(mask & POLLFREE)) { + io_poll_mark_cancelled(req); + /* we have to kick tw in case it's not already */ + io_poll_execute(req, 0);

- list_del_init(&wait->entry); + /* + * If the waitqueue is being freed early but someone is already + * holds ownership over it, we have to tear down the request as + * best we can. That means immediately removing the request from + * its waitqueue and preventing all further accesses to the + * waitqueue via the request. + */ + list_del_init(&poll->wait.entry);

- if (poll && poll->head) { - bool done; - - spin_lock(&poll->head->lock); - done = list_empty(&poll->wait.entry); - if (!done) - list_del_init(&poll->wait.entry); - /* make sure double remove sees this as being gone */ - wait->private = NULL; - spin_unlock(&poll->head->lock); - if (!done) { - /* use wait func handler, so it matches the rq type */ - poll->wait.func(&poll->wait, mode, sync, key); - } + /* + * Careful: this *must* be the last step, since as soon + * as req->head is NULL'ed out, the request can be + * completed and freed, since aio_poll_complete_work() + * will no longer need to take the waitqueue lock. + */ + smp_store_release(&poll->head, NULL); + return 1; } - refcount_dec(&req->refs); + + /* for instances that support it check for an event match first */ + if (mask && !(mask & poll->events)) + return 0; + + if (io_poll_get_ownership(req)) + __io_poll_execute(req, mask); return 1; }

-static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events, - wait_queue_func_t wake_func) -{ - poll->head = NULL; - poll->done = false; - poll->canceled = false; - poll->events = events; - INIT_LIST_HEAD(&poll->wait.entry); - init_waitqueue_func_entry(&poll->wait, wake_func); -} - static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt, struct wait_queue_head *head, struct io_poll_iocb **poll_ptr) @@ -5099,29 +5494,31 @@ static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt, * if this happens. */ if (unlikely(pt->nr_entries)) { - struct io_poll_iocb *poll_one = poll; + struct io_poll_iocb *first = poll;

+ /* double add on the same waitqueue head, ignore */ + if (first->head == head) + return; /* already have a 2nd entry, fail a third attempt */ if (*poll_ptr) { + if ((*poll_ptr)->head == head) + return; pt->error = -EINVAL; return; } - /* double add on the same waitqueue head, ignore */ - if (poll->head == head) - return; + poll = kmalloc(sizeof(*poll), GFP_ATOMIC); if (!poll) { pt->error = -ENOMEM; return; } - io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake); - refcount_inc(&req->refs); - poll->wait.private = req; + io_init_poll_iocb(poll, first->events, first->wait.func); *poll_ptr = poll; }

pt->nr_entries++; poll->head = head; + poll->wait.private = req;

if (poll->events & EPOLLEXCLUSIVE) add_wait_queue_exclusive(head, &poll->wait); @@ -5129,83 +5526,23 @@ static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt, add_wait_queue(head, &poll->wait); }

-static void io_async_queue_proc(struct file *file, struct wait_queue_head *head, +static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head, struct poll_table_struct *p) { struct io_poll_table *pt = container_of(p, struct io_poll_table, pt); - struct async_poll *apoll = pt->req->apoll; - - __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll); -} - -static void io_async_task_func(struct callback_head *cb) -{ - struct io_kiocb *req = container_of(cb, struct io_kiocb, task_work); - struct async_poll *apoll = req->apoll; - struct io_ring_ctx *ctx = req->ctx; - - trace_io_uring_task_run(req->ctx, req->opcode, req->user_data); - - if (io_poll_rewait(req, &apoll->poll)) { - spin_unlock_irq(&ctx->completion_lock); - percpu_ref_put(&ctx->refs); - return; - } - - /* If req is still hashed, it cannot have been canceled. Don't check. */ - if (hash_hashed(&req->hash_node)) - hash_del(&req->hash_node); - - io_poll_remove_double(req); - spin_unlock_irq(&ctx->completion_lock); - - if (!READ_ONCE(apoll->poll.canceled)) - __io_req_task_submit(req); - else - __io_req_task_cancel(req, -ECANCELED);

- percpu_ref_put(&ctx->refs); - kfree(apoll->double_poll); - kfree(apoll); -} - -static int io_async_wake(struct wait_queue_entry *wait, unsigned mode, int sync, - void *key) -{ - struct io_kiocb *req = wait->private; - struct io_poll_iocb *poll = &req->apoll->poll; - - trace_io_uring_poll_wake(req->ctx, req->opcode, req->user_data, - key_to_poll(key)); - - return __io_async_wake(req, poll, key_to_poll(key), io_async_task_func); -} - -static void io_poll_req_insert(struct io_kiocb *req) -{ - struct io_ring_ctx *ctx = req->ctx; - struct hlist_head *list; - - list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)]; - hlist_add_head(&req->hash_node, list); + __io_queue_proc(&pt->req->poll, pt, head, + (struct io_poll_iocb **) &pt->req->async_data); }

-static __poll_t __io_arm_poll_handler(struct io_kiocb *req, - struct io_poll_iocb *poll, - struct io_poll_table *ipt, __poll_t mask, - wait_queue_func_t wake_func) - __acquires(&ctx->completion_lock) +static int __io_arm_poll_handler(struct io_kiocb *req, + struct io_poll_iocb *poll, + struct io_poll_table *ipt, __poll_t mask) { struct io_ring_ctx *ctx = req->ctx; - bool cancel = false; - - if (req->file->f_op->may_pollfree) { - spin_lock_irq(&ctx->completion_lock); - return -EOPNOTSUPP; - }

INIT_HLIST_NODE(&req->hash_node); - io_init_poll_iocb(poll, mask, wake_func); + io_init_poll_iocb(poll, mask, io_poll_wake); poll->file = req->file; poll->wait.private = req;

@@ -5214,169 +5551,138 @@ static __poll_t __io_arm_poll_handler(struct io_kiocb *req, ipt->error = 0; ipt->nr_entries = 0;

+ /* + * Take the ownership to delay any tw execution up until we're done + * with poll arming. see io_poll_get_ownership(). + */ + atomic_set(&req->poll_refs, 1); mask = vfs_poll(req->file, &ipt->pt) & poll->events; - if (unlikely(!ipt->nr_entries) && !ipt->error) - ipt->error = -EINVAL; - - spin_lock_irq(&ctx->completion_lock); - if (ipt->error) - io_poll_remove_double(req); - if (likely(poll->head)) { - spin_lock(&poll->head->lock); - if (unlikely(list_empty(&poll->wait.entry))) { - if (ipt->error) - cancel = true; + + if (mask && (poll->events & EPOLLONESHOT)) { + io_poll_remove_entries(req); + /* no one else has access to the req, forget about the ref */ + return mask; + } + if (!mask && unlikely(ipt->error || !ipt->nr_entries)) { + io_poll_remove_entries(req); + if (!ipt->error) + ipt->error = -EINVAL; + return 0; + } + + spin_lock(&ctx->completion_lock); + io_poll_req_insert(req); + spin_unlock(&ctx->completion_lock); + + if (mask) { + /* can't multishot if failed, just queue the event we've got */ + if (unlikely(ipt->error || !ipt->nr_entries)) { + poll->events |= EPOLLONESHOT; ipt->error = 0; - mask = 0; } - if (mask || ipt->error) - list_del_init(&poll->wait.entry); - else if (cancel) - WRITE_ONCE(poll->canceled, true); - else if (!poll->done) /* actually waiting for an event */ - io_poll_req_insert(req); - spin_unlock(&poll->head->lock); + __io_poll_execute(req, mask); + return 0; }

- return mask; + /* + * Try to release ownership. If we see a change of state, e.g. + * poll was waken up, queue up a tw, it'll deal with it. + */ + if (atomic_cmpxchg(&req->poll_refs, 1, 0) != 1) + __io_poll_execute(req, 0); + return 0; +} + +static void io_async_queue_proc(struct file *file, struct wait_queue_head *head, + struct poll_table_struct *p) +{ + struct io_poll_table *pt = container_of(p, struct io_poll_table, pt); + struct async_poll *apoll = pt->req->apoll; + + __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll); }

-static bool io_arm_poll_handler(struct io_kiocb *req) +enum { + IO_APOLL_OK, + IO_APOLL_ABORTED, + IO_APOLL_READY +}; + +static int io_arm_poll_handler(struct io_kiocb *req) { const struct io_op_def *def = &io_op_defs[req->opcode]; struct io_ring_ctx *ctx = req->ctx; struct async_poll *apoll; struct io_poll_table ipt; - __poll_t mask, ret; - int rw; + __poll_t mask = EPOLLONESHOT | POLLERR | POLLPRI; + int ret;

if (!req->file || !file_can_poll(req->file)) - return false; + return IO_APOLL_ABORTED; if (req->flags & REQ_F_POLLED) - return false; - if (def->pollin) - rw = READ; - else if (def->pollout) - rw = WRITE; - else - return false; - /* if we can't nonblock try, then no point in arming a poll handler */ - if (!io_file_supports_async(req->file, rw)) - return false; + return IO_APOLL_ABORTED; + if (!def->pollin && !def->pollout) + return IO_APOLL_ABORTED; + + if (def->pollin) { + mask |= POLLIN | POLLRDNORM; + + /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */ + if ((req->opcode == IORING_OP_RECVMSG) && + (req->sr_msg.msg_flags & MSG_ERRQUEUE)) + mask &= ~POLLIN; + } else { + mask |= POLLOUT | POLLWRNORM; + }

apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC); if (unlikely(!apoll)) - return false; + return IO_APOLL_ABORTED; apoll->double_poll = NULL; - - req->flags |= REQ_F_POLLED; req->apoll = apoll; - - mask = 0; - if (def->pollin) - mask |= POLLIN | POLLRDNORM; - if (def->pollout) - mask |= POLLOUT | POLLWRNORM; - - /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */ - if ((req->opcode == IORING_OP_RECVMSG) && - (req->sr_msg.msg_flags & MSG_ERRQUEUE)) - mask &= ~POLLIN; - - mask |= POLLERR | POLLPRI; - + req->flags |= REQ_F_POLLED; ipt.pt._qproc = io_async_queue_proc;

- ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask, - io_async_wake); - if (ret || ipt.error) { - io_poll_remove_double(req); - spin_unlock_irq(&ctx->completion_lock); - kfree(apoll->double_poll); - kfree(apoll); - return false; - } - spin_unlock_irq(&ctx->completion_lock); - trace_io_uring_poll_arm(ctx, req->opcode, req->user_data, mask, - apoll->poll.events); - return true; -} - -static bool __io_poll_remove_one(struct io_kiocb *req, - struct io_poll_iocb *poll) -{ - bool do_complete = false; - - spin_lock(&poll->head->lock); - WRITE_ONCE(poll->canceled, true); - if (!list_empty(&poll->wait.entry)) { - list_del_init(&poll->wait.entry); - do_complete = true; - } - spin_unlock(&poll->head->lock); - hash_del(&req->hash_node); - return do_complete; -} - -static bool io_poll_remove_one(struct io_kiocb *req) -{ - bool do_complete; - - io_poll_remove_double(req); - - if (req->opcode == IORING_OP_POLL_ADD) { - do_complete = __io_poll_remove_one(req, &req->poll); - } else { - struct async_poll *apoll = req->apoll; - - /* non-poll requests have submit ref still */ - do_complete = __io_poll_remove_one(req, &apoll->poll); - if (do_complete) { - io_put_req(req); - kfree(apoll->double_poll); - kfree(apoll); - } - } - - if (do_complete) { - io_cqring_fill_event(req, -ECANCELED); - io_commit_cqring(req->ctx); - req_set_fail_links(req); - io_put_req_deferred(req, 1); - } + ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask); + if (ret || ipt.error) + return ret ? IO_APOLL_READY : IO_APOLL_ABORTED;

- return do_complete; + trace_io_uring_poll_arm(ctx, req, req->opcode, req->user_data, + mask, apoll->poll.events); + return IO_APOLL_OK; }

/* * Returns true if we found and killed one or more poll requests */ static bool io_poll_remove_all(struct io_ring_ctx *ctx, struct task_struct *tsk, - struct files_struct *files) + bool cancel_all) { struct hlist_node *tmp; struct io_kiocb *req; - int posted = 0, i; + bool found = false; + int i;

- spin_lock_irq(&ctx->completion_lock); + spin_lock(&ctx->completion_lock); for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) { struct hlist_head *list;

list = &ctx->cancel_hash[i]; hlist_for_each_entry_safe(req, tmp, list, hash_node) { - if (io_match_task(req, tsk, files)) - posted += io_poll_remove_one(req); + if (io_match_task_safe(req, tsk, cancel_all)) { + hlist_del_init(&req->hash_node); + io_poll_cancel_req(req); + found = true; + } } } - spin_unlock_irq(&ctx->completion_lock); - - if (posted) - io_cqring_ev_posted(ctx); - - return posted != 0; + spin_unlock(&ctx->completion_lock); + return found; }

-static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr) +static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, __u64 sqe_addr, + bool poll_only) + __must_hold(&ctx->completion_lock) { struct hlist_head *list; struct io_kiocb *req; @@ -5385,107 +5691,161 @@ static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr) hlist_for_each_entry(req, list, hash_node) { if (sqe_addr != req->user_data) continue; - if (io_poll_remove_one(req)) - return 0; - return -EALREADY; + if (poll_only && req->opcode != IORING_OP_POLL_ADD) + continue; + return req; } - - return -ENOENT; + return NULL; }

-static int io_poll_remove_prep(struct io_kiocb *req, - const struct io_uring_sqe *sqe) +static bool io_poll_disarm(struct io_kiocb *req) + __must_hold(&ctx->completion_lock) { - if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) - return -EINVAL; - if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index || - sqe->poll_events) - return -EINVAL; - - req->poll.addr = READ_ONCE(sqe->addr); - return 0; + if (!io_poll_get_ownership(req)) + return false; + io_poll_remove_entries(req); + hash_del(&req->hash_node); + return true; }

-/* - * Find a running poll command that matches one specified in sqe->addr, - * and remove it if found. - */ -static int io_poll_remove(struct io_kiocb *req) +static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr, + bool poll_only) + __must_hold(&ctx->completion_lock) { - struct io_ring_ctx *ctx = req->ctx; - u64 addr; - int ret; + struct io_kiocb *req = io_poll_find(ctx, sqe_addr, poll_only);

- addr = req->poll.addr; - spin_lock_irq(&ctx->completion_lock); - ret = io_poll_cancel(ctx, addr); - spin_unlock_irq(&ctx->completion_lock); - - if (ret < 0) - req_set_fail_links(req); - io_req_complete(req, ret); + if (!req) + return -ENOENT; + io_poll_cancel_req(req); return 0; }

-static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync, - void *key) +static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe, + unsigned int flags) { - struct io_kiocb *req = wait->private; - struct io_poll_iocb *poll = &req->poll; + u32 events;

- return __io_async_wake(req, poll, key_to_poll(key), io_poll_task_func); + events = READ_ONCE(sqe->poll32_events); +#ifdef __BIG_ENDIAN + events = swahw32(events); +#endif + if (!(flags & IORING_POLL_ADD_MULTI)) + events |= EPOLLONESHOT; + return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT)); }

-static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head, - struct poll_table_struct *p) +static int io_poll_update_prep(struct io_kiocb *req, + const struct io_uring_sqe *sqe) { - struct io_poll_table *pt = container_of(p, struct io_poll_table, pt); + struct io_poll_update *upd = &req->poll_update; + u32 flags; + + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) + return -EINVAL; + if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in) + return -EINVAL; + flags = READ_ONCE(sqe->len); + if (flags & ~(IORING_POLL_UPDATE_EVENTS | IORING_POLL_UPDATE_USER_DATA | + IORING_POLL_ADD_MULTI)) + return -EINVAL; + /* meaningless without update */ + if (flags == IORING_POLL_ADD_MULTI) + return -EINVAL; + + upd->old_user_data = READ_ONCE(sqe->addr); + upd->update_events = flags & IORING_POLL_UPDATE_EVENTS; + upd->update_user_data = flags & IORING_POLL_UPDATE_USER_DATA; + + upd->new_user_data = READ_ONCE(sqe->off); + if (!upd->update_user_data && upd->new_user_data) + return -EINVAL; + if (upd->update_events) + upd->events = io_poll_parse_events(sqe, flags); + else if (sqe->poll32_events) + return -EINVAL;

- __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data); + return 0; }

static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { struct io_poll_iocb *poll = &req->poll; - u32 events; + u32 flags;

if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; - if (sqe->addr || sqe->ioprio || sqe->off || sqe->len || sqe->buf_index) + if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->addr) + return -EINVAL; + flags = READ_ONCE(sqe->len); + if (flags & ~IORING_POLL_ADD_MULTI) return -EINVAL;

- events = READ_ONCE(sqe->poll32_events); -#ifdef __BIG_ENDIAN - events = swahw32(events); -#endif - poll->events = demangle_poll(events) | EPOLLERR | EPOLLHUP | - (events & EPOLLEXCLUSIVE); + io_req_set_refcount(req); + poll->events = io_poll_parse_events(sqe, flags); return 0; }

-static int io_poll_add(struct io_kiocb *req) +static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags) { struct io_poll_iocb *poll = &req->poll; - struct io_ring_ctx *ctx = req->ctx; struct io_poll_table ipt; - __poll_t mask; + int ret;

ipt.pt._qproc = io_poll_queue_proc;

- mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events, - io_poll_wake); + ret = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events); + if (!ret && ipt.error) + req_set_fail(req); + ret = ret ?: ipt.error; + if (ret) + __io_req_complete(req, issue_flags, ret, 0); + return 0; +}

- if (mask) { /* no async, we'd stolen it */ - ipt.error = 0; - io_poll_complete(req, mask, 0); +static int io_poll_update(struct io_kiocb *req, unsigned int issue_flags) +{ + struct io_ring_ctx *ctx = req->ctx; + struct io_kiocb *preq; + int ret2, ret = 0; + + spin_lock(&ctx->completion_lock); + preq = io_poll_find(ctx, req->poll_update.old_user_data, true); + if (!preq || !io_poll_disarm(preq)) { + spin_unlock(&ctx->completion_lock); + ret = preq ? -EALREADY : -ENOENT; + goto out; } - spin_unlock_irq(&ctx->completion_lock); + spin_unlock(&ctx->completion_lock);

- if (mask) { - io_cqring_ev_posted(ctx); - io_put_req(req); + if (req->poll_update.update_events || req->poll_update.update_user_data) { + /* only mask one event flags, keep behavior flags */ + if (req->poll_update.update_events) { + preq->poll.events &= ~0xffff; + preq->poll.events |= req->poll_update.events & 0xffff; + preq->poll.events |= IO_POLL_UNMASK; + } + if (req->poll_update.update_user_data) + preq->user_data = req->poll_update.new_user_data; + + ret2 = io_poll_add(preq, issue_flags); + /* successfully updated, don't complete poll request */ + if (!ret2) + goto out; } - return ipt.error; + req_set_fail(preq); + io_req_complete(preq, -ECANCELED); +out: + if (ret < 0) + req_set_fail(req); + /* complete update request, we're done with it */ + io_req_complete(req, ret); + return 0; +} + +static void io_req_task_timeout(struct io_kiocb *req, bool *locked) +{ + req_set_fail(req); + io_req_complete_post(req, -ETIME, 0); }

static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer) @@ -5496,88 +5856,182 @@ static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer) struct io_ring_ctx *ctx = req->ctx; unsigned long flags;

- spin_lock_irqsave(&ctx->completion_lock, flags); + spin_lock_irqsave(&ctx->timeout_lock, flags); list_del_init(&req->timeout.list); atomic_set(&req->ctx->cq_timeouts, atomic_read(&req->ctx->cq_timeouts) + 1); + spin_unlock_irqrestore(&ctx->timeout_lock, flags);

- io_cqring_fill_event(req, -ETIME); - io_commit_cqring(ctx); - spin_unlock_irqrestore(&ctx->completion_lock, flags); - - io_cqring_ev_posted(ctx); - req_set_fail_links(req); - io_put_req(req); + req->io_task_work.func = io_req_task_timeout; + io_req_task_work_add(req); return HRTIMER_NORESTART; }

-static int __io_timeout_cancel(struct io_kiocb *req) +static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx, + __u64 user_data) + __must_hold(&ctx->timeout_lock) { - struct io_timeout_data *io = req->async_data; - int ret; + struct io_timeout_data *io; + struct io_kiocb *req; + bool found = false;

- ret = hrtimer_try_to_cancel(&io->timer); - if (ret == -1) - return -EALREADY; + list_for_each_entry(req, &ctx->timeout_list, timeout.list) { + found = user_data == req->user_data; + if (found) + break; + } + if (!found) + return ERR_PTR(-ENOENT); + + io = req->async_data; + if (hrtimer_try_to_cancel(&io->timer) == -1) + return ERR_PTR(-EALREADY); list_del_init(&req->timeout.list); + return req; +} + +static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data) + __must_hold(&ctx->completion_lock) + __must_hold(&ctx->timeout_lock) +{ + struct io_kiocb *req = io_timeout_extract(ctx, user_data);

- req_set_fail_links(req); - io_cqring_fill_event(req, -ECANCELED); - io_put_req_deferred(req, 1); + if (IS_ERR(req)) + return PTR_ERR(req); + + req_set_fail(req); + io_fill_cqe_req(req, -ECANCELED, 0); + io_put_req_deferred(req); return 0; }

-static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data) +static clockid_t io_timeout_get_clock(struct io_timeout_data *data) +{ + switch (data->flags & IORING_TIMEOUT_CLOCK_MASK) { + case IORING_TIMEOUT_BOOTTIME: + return CLOCK_BOOTTIME; + case IORING_TIMEOUT_REALTIME: + return CLOCK_REALTIME; + default: + /* can't happen, vetted at prep time */ + WARN_ON_ONCE(1); + fallthrough; + case 0: + return CLOCK_MONOTONIC; + } +} + +static int io_linked_timeout_update(struct io_ring_ctx *ctx, __u64 user_data, + struct timespec64 *ts, enum hrtimer_mode mode) + __must_hold(&ctx->timeout_lock) { + struct io_timeout_data *io; struct io_kiocb *req; - int ret = -ENOENT; + bool found = false;

- list_for_each_entry(req, &ctx->timeout_list, timeout.list) { - if (user_data == req->user_data) { - ret = 0; + list_for_each_entry(req, &ctx->ltimeout_list, timeout.list) { + found = user_data == req->user_data; + if (found) break; - } } + if (!found) + return -ENOENT;

- if (ret == -ENOENT) - return ret; + io = req->async_data; + if (hrtimer_try_to_cancel(&io->timer) == -1) + return -EALREADY; + hrtimer_init(&io->timer, io_timeout_get_clock(io), mode); + io->timer.function = io_link_timeout_fn; + hrtimer_start(&io->timer, timespec64_to_ktime(*ts), mode); + return 0; +}

- return __io_timeout_cancel(req); +static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data, + struct timespec64 *ts, enum hrtimer_mode mode) + __must_hold(&ctx->timeout_lock) +{ + struct io_kiocb *req = io_timeout_extract(ctx, user_data); + struct io_timeout_data *data; + + if (IS_ERR(req)) + return PTR_ERR(req); + + req->timeout.off = 0; /* noseq */ + data = req->async_data; + list_add_tail(&req->timeout.list, &ctx->timeout_list); + hrtimer_init(&data->timer, io_timeout_get_clock(data), mode); + data->timer.function = io_timeout_fn; + hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode); + return 0; }

static int io_timeout_remove_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { + struct io_timeout_rem *tr = &req->timeout_rem; + if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL)) return -EINVAL; if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT))) return -EINVAL; - if (sqe->ioprio || sqe->buf_index || sqe->len || sqe->timeout_flags || - sqe->splice_fd_in) + if (sqe->ioprio || sqe->buf_index || sqe->len || sqe->splice_fd_in) + return -EINVAL; + + tr->ltimeout = false; + tr->addr = READ_ONCE(sqe->addr); + tr->flags = READ_ONCE(sqe->timeout_flags); + if (tr->flags & IORING_TIMEOUT_UPDATE_MASK) { + if (hweight32(tr->flags & IORING_TIMEOUT_CLOCK_MASK) > 1) + return -EINVAL; + if (tr->flags & IORING_LINK_TIMEOUT_UPDATE) + tr->ltimeout = true; + if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK|IORING_TIMEOUT_ABS)) + return -EINVAL; + if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2))) + return -EFAULT; + } else if (tr->flags) { + /* timeout removal doesn't support flags */ return -EINVAL; + }

- req->timeout_rem.addr = READ_ONCE(sqe->addr); return 0; }

+static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags) +{ + return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS + : HRTIMER_MODE_REL; +} + /* * Remove or update an existing timeout command */ -static int io_timeout_remove(struct io_kiocb *req) +static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags) { + struct io_timeout_rem *tr = &req->timeout_rem; struct io_ring_ctx *ctx = req->ctx; int ret;

- spin_lock_irq(&ctx->completion_lock); - ret = io_timeout_cancel(ctx, req->timeout_rem.addr); + if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE)) { + spin_lock(&ctx->completion_lock); + spin_lock_irq(&ctx->timeout_lock); + ret = io_timeout_cancel(ctx, tr->addr); + spin_unlock_irq(&ctx->timeout_lock); + spin_unlock(&ctx->completion_lock); + } else { + enum hrtimer_mode mode = io_translate_timeout_mode(tr->flags); + + spin_lock_irq(&ctx->timeout_lock); + if (tr->ltimeout) + ret = io_linked_timeout_update(ctx, tr->addr, &tr->ts, mode); + else + ret = io_timeout_update(ctx, tr->addr, &tr->ts, mode); + spin_unlock_irq(&ctx->timeout_lock); + }

- io_cqring_fill_event(req, ret); - io_commit_cqring(ctx); - spin_unlock_irq(&ctx->completion_lock); - io_cqring_ev_posted(ctx); if (ret < 0) - req_set_fail_links(req); - io_put_req(req); + req_set_fail(req); + io_req_complete_post(req, ret, 0); return 0; }

@@ -5596,38 +6050,52 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe, if (off && is_timeout_link) return -EINVAL; flags = READ_ONCE(sqe->timeout_flags); - if (flags & ~IORING_TIMEOUT_ABS) + if (flags & ~(IORING_TIMEOUT_ABS | IORING_TIMEOUT_CLOCK_MASK)) + return -EINVAL; + /* more than one clock specified is invalid, obviously */ + if (hweight32(flags & IORING_TIMEOUT_CLOCK_MASK) > 1) return -EINVAL;

+ INIT_LIST_HEAD(&req->timeout.list); req->timeout.off = off; + if (unlikely(off && !req->ctx->off_timeout_used)) + req->ctx->off_timeout_used = true;

if (!req->async_data && io_alloc_async_data(req)) return -ENOMEM;

data = req->async_data; data->req = req; + data->flags = flags;

if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr))) return -EFAULT;

- if (flags & IORING_TIMEOUT_ABS) - data->mode = HRTIMER_MODE_ABS; - else - data->mode = HRTIMER_MODE_REL; - INIT_LIST_HEAD(&req->timeout.list); - hrtimer_init(&data->timer, CLOCK_MONOTONIC, data->mode); + data->mode = io_translate_timeout_mode(flags); + hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode); + + if (is_timeout_link) { + struct io_submit_link *link = &req->ctx->submit_state.link; + + if (!link->head) + return -EINVAL; + if (link->last->opcode == IORING_OP_LINK_TIMEOUT) + return -EINVAL; + req->timeout.head = link->last; + link->last->flags |= REQ_F_ARM_LTIMEOUT; + } return 0; }

-static int io_timeout(struct io_kiocb *req) +static int io_timeout(struct io_kiocb *req, unsigned int issue_flags) { struct io_ring_ctx *ctx = req->ctx; struct io_timeout_data *data = req->async_data; struct list_head *entry; u32 tail, off = req->timeout.off;

- spin_lock_irq(&ctx->completion_lock); + spin_lock_irq(&ctx->timeout_lock);

/* * sqe->off holds how many events that need to occur for this @@ -5666,23 +6134,34 @@ static int io_timeout(struct io_kiocb *req) list_add(&req->timeout.list, entry); data->timer.function = io_timeout_fn; hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode); - spin_unlock_irq(&ctx->completion_lock); + spin_unlock_irq(&ctx->timeout_lock); return 0; }

+struct io_cancel_data { + struct io_ring_ctx *ctx; + u64 user_data; +}; + static bool io_cancel_cb(struct io_wq_work *work, void *data) { struct io_kiocb *req = container_of(work, struct io_kiocb, work); + struct io_cancel_data *cd = data;

- return req->user_data == (unsigned long) data; + return req->ctx == cd->ctx && req->user_data == cd->user_data; }

-static int io_async_cancel_one(struct io_ring_ctx *ctx, void *sqe_addr) +static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data, + struct io_ring_ctx *ctx) { + struct io_cancel_data data = { .ctx = ctx, .user_data = user_data, }; enum io_wq_cancel cancel_ret; int ret = 0;

- cancel_ret = io_wq_cancel_cb(ctx->io_wq, io_cancel_cb, sqe_addr, false); + if (!tctx || !tctx->io_wq) + return -ENOENT; + + cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, &data, false); switch (cancel_ret) { case IO_WQ_CANCEL_OK: ret = 0; @@ -5698,35 +6177,27 @@ static int io_async_cancel_one(struct io_ring_ctx *ctx, void *sqe_addr) return ret; }

-static void io_async_find_and_cancel(struct io_ring_ctx *ctx, - struct io_kiocb *req, __u64 sqe_addr, - int success_ret) +static int io_try_cancel_userdata(struct io_kiocb *req, u64 sqe_addr) { - unsigned long flags; + struct io_ring_ctx *ctx = req->ctx; int ret;

- ret = io_async_cancel_one(ctx, (void *) (unsigned long) sqe_addr); - if (ret != -ENOENT) { - spin_lock_irqsave(&ctx->completion_lock, flags); - goto done; - } + WARN_ON_ONCE(!io_wq_current_is_worker() && req->task != current);

- spin_lock_irqsave(&ctx->completion_lock, flags); - ret = io_timeout_cancel(ctx, sqe_addr); + ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx); if (ret != -ENOENT) - goto done; - ret = io_poll_cancel(ctx, sqe_addr); -done: - if (!ret) - ret = success_ret; - io_cqring_fill_event(req, ret); - io_commit_cqring(ctx); - spin_unlock_irqrestore(&ctx->completion_lock, flags); - io_cqring_ev_posted(ctx); + return ret;

- if (ret < 0) - req_set_fail_links(req); - io_put_req(req); + spin_lock(&ctx->completion_lock); + spin_lock_irq(&ctx->timeout_lock); + ret = io_timeout_cancel(ctx, sqe_addr); + spin_unlock_irq(&ctx->timeout_lock); + if (ret != -ENOENT) + goto out; + ret = io_poll_cancel(ctx, sqe_addr, false); +out: + spin_unlock(&ctx->completion_lock); + return ret; }

static int io_async_cancel_prep(struct io_kiocb *req, @@ -5744,52 +6215,72 @@ static int io_async_cancel_prep(struct io_kiocb *req, return 0; }

-static int io_async_cancel(struct io_kiocb *req) +static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags) { struct io_ring_ctx *ctx = req->ctx; + u64 sqe_addr = req->cancel.addr; + struct io_tctx_node *node; + int ret; + + ret = io_try_cancel_userdata(req, sqe_addr); + if (ret != -ENOENT) + goto done; + + /* slow path, try all io-wq's */ + io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK)); + ret = -ENOENT; + list_for_each_entry(node, &ctx->tctx_list, ctx_node) { + struct io_uring_task *tctx = node->task->io_uring;

- io_async_find_and_cancel(ctx, req, req->cancel.addr, 0); + ret = io_async_cancel_one(tctx, req->cancel.addr, ctx); + if (ret != -ENOENT) + break; + } + io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK)); +done: + if (ret < 0) + req_set_fail(req); + io_req_complete_post(req, ret, 0); return 0; }

-static int io_files_update_prep(struct io_kiocb *req, +static int io_rsrc_update_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { - if (unlikely(req->ctx->flags & IORING_SETUP_SQPOLL)) - return -EINVAL; if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT))) return -EINVAL; - if (sqe->ioprio || sqe->rw_flags) + if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in) return -EINVAL;

- req->files_update.offset = READ_ONCE(sqe->off); - req->files_update.nr_args = READ_ONCE(sqe->len); - if (!req->files_update.nr_args) + req->rsrc_update.offset = READ_ONCE(sqe->off); + req->rsrc_update.nr_args = READ_ONCE(sqe->len); + if (!req->rsrc_update.nr_args) return -EINVAL; - req->files_update.arg = READ_ONCE(sqe->addr); + req->rsrc_update.arg = READ_ONCE(sqe->addr); return 0; }

-static int io_files_update(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_files_update(struct io_kiocb *req, unsigned int issue_flags) { struct io_ring_ctx *ctx = req->ctx; - struct io_uring_files_update up; + struct io_uring_rsrc_update2 up; int ret;

- if (force_nonblock) - return -EAGAIN; - - up.offset = req->files_update.offset; - up.fds = req->files_update.arg; + up.offset = req->rsrc_update.offset; + up.data = req->rsrc_update.arg; + up.nr = 0; + up.tags = 0; + up.resv = 0; + up.resv2 = 0;

- mutex_lock(&ctx->uring_lock); - ret = __io_sqe_files_update(ctx, &up, req->files_update.nr_args); - mutex_unlock(&ctx->uring_lock); + io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK)); + ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE, + &up, req->rsrc_update.nr_args); + io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK));

if (ret < 0) - req_set_fail_links(req); - __io_req_complete(req, ret, 0, cs); + req_set_fail(req); + __io_req_complete(req, issue_flags, ret, 0); return 0; }

@@ -5809,11 +6300,11 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) case IORING_OP_POLL_ADD: return io_poll_add_prep(req, sqe); case IORING_OP_POLL_REMOVE: - return io_poll_remove_prep(req, sqe); + return io_poll_update_prep(req, sqe); case IORING_OP_FSYNC: - return io_prep_fsync(req, sqe); + return io_fsync_prep(req, sqe); case IORING_OP_SYNC_FILE_RANGE: - return io_prep_sfr(req, sqe); + return io_sfr_prep(req, sqe); case IORING_OP_SENDMSG: case IORING_OP_SEND: return io_sendmsg_prep(req, sqe); @@ -5839,7 +6330,7 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) case IORING_OP_CLOSE: return io_close_prep(req, sqe); case IORING_OP_FILES_UPDATE: - return io_files_update_prep(req, sqe); + return io_rsrc_update_prep(req, sqe); case IORING_OP_STATX: return io_statx_prep(req, sqe); case IORING_OP_FADVISE: @@ -5858,100 +6349,131 @@ static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) return io_remove_buffers_prep(req, sqe); case IORING_OP_TEE: return io_tee_prep(req, sqe); + case IORING_OP_SHUTDOWN: + return io_shutdown_prep(req, sqe); + case IORING_OP_RENAMEAT: + return io_renameat_prep(req, sqe); + case IORING_OP_UNLINKAT: + return io_unlinkat_prep(req, sqe); }

printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n", req->opcode); - return-EINVAL; + return -EINVAL; }

-static int io_req_defer_prep(struct io_kiocb *req, - const struct io_uring_sqe *sqe) +static int io_req_prep_async(struct io_kiocb *req) { - if (!sqe) + if (!io_op_defs[req->opcode].needs_async_setup) return 0; + if (WARN_ON_ONCE(req->async_data)) + return -EFAULT; if (io_alloc_async_data(req)) return -EAGAIN; - return io_req_prep(req, sqe); + + switch (req->opcode) { + case IORING_OP_READV: + return io_rw_prep_async(req, READ); + case IORING_OP_WRITEV: + return io_rw_prep_async(req, WRITE); + case IORING_OP_SENDMSG: + return io_sendmsg_prep_async(req); + case IORING_OP_RECVMSG: + return io_recvmsg_prep_async(req); + case IORING_OP_CONNECT: + return io_connect_prep_async(req); + } + printk_once(KERN_WARNING "io_uring: prep_async() bad opcode %d\n", + req->opcode); + return -EFAULT; }

static u32 io_get_sequence(struct io_kiocb *req) { - struct io_kiocb *pos; - struct io_ring_ctx *ctx = req->ctx; - u32 total_submitted, nr_reqs = 1; + u32 seq = req->ctx->cached_sq_head;

- if (req->flags & REQ_F_LINK_HEAD) - list_for_each_entry(pos, &req->link_list, link_list) - nr_reqs++; - - total_submitted = ctx->cached_sq_head - ctx->cached_sq_dropped; - return total_submitted - nr_reqs; + /* need original cached_sq_head, but it was increased for each req */ + io_for_each_link(req, req) + seq--; + return seq; }

-static int io_req_defer(struct io_kiocb *req, const struct io_uring_sqe *sqe) +static bool io_drain_req(struct io_kiocb *req) { + struct io_kiocb *pos; struct io_ring_ctx *ctx = req->ctx; struct io_defer_entry *de; int ret; u32 seq;

+ if (req->flags & REQ_F_FAIL) { + io_req_complete_fail_submit(req); + return true; + } + + /* + * If we need to drain a request in the middle of a link, drain the + * head request and the next request/link after the current link. + * Considering sequential execution of links, IOSQE_IO_DRAIN will be + * maintained for every request of our link. + */ + if (ctx->drain_next) { + req->flags |= REQ_F_IO_DRAIN; + ctx->drain_next = false; + } + /* not interested in head, start from the first linked */ + io_for_each_link(pos, req->link) { + if (pos->flags & REQ_F_IO_DRAIN) { + ctx->drain_next = true; + req->flags |= REQ_F_IO_DRAIN; + break; + } + } + /* Still need defer if there is pending req in defer list. */ + spin_lock(&ctx->completion_lock); if (likely(list_empty_careful(&ctx->defer_list) && - !(req->flags & REQ_F_IO_DRAIN))) - return 0; + !(req->flags & REQ_F_IO_DRAIN))) { + spin_unlock(&ctx->completion_lock); + ctx->drain_active = false; + return false; + } + spin_unlock(&ctx->completion_lock);

seq = io_get_sequence(req); /* Still a chance to pass the sequence check */ if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list)) - return 0; + return false;

- if (!req->async_data) { - ret = io_req_defer_prep(req, sqe); - if (ret) - return ret; - } + ret = io_req_prep_async(req); + if (ret) + goto fail; io_prep_async_link(req); de = kmalloc(sizeof(*de), GFP_KERNEL); - if (!de) - return -ENOMEM; + if (!de) { + ret = -ENOMEM; +fail: + io_req_complete_failed(req, ret); + return true; + }

- spin_lock_irq(&ctx->completion_lock); + spin_lock(&ctx->completion_lock); if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) { - spin_unlock_irq(&ctx->completion_lock); + spin_unlock(&ctx->completion_lock); kfree(de); - io_queue_async_work(req); - return -EIOCBQUEUED; + io_queue_async_work(req, NULL); + return true; }

trace_io_uring_defer(ctx, req, req->user_data); de->req = req; de->seq = seq; list_add_tail(&de->list, &ctx->defer_list); - spin_unlock_irq(&ctx->completion_lock); - return -EIOCBQUEUED; -} - -static void io_req_drop_files(struct io_kiocb *req) -{ - struct io_ring_ctx *ctx = req->ctx; - struct io_uring_task *tctx = req->task->io_uring; - unsigned long flags; - - if (req->work.flags & IO_WQ_WORK_FILES) { - put_files_struct(req->work.identity->files); - put_nsproxy(req->work.identity->nsproxy); - } - spin_lock_irqsave(&ctx->inflight_lock, flags); - list_del(&req->inflight_entry); - spin_unlock_irqrestore(&ctx->inflight_lock, flags); - req->flags &= ~REQ_F_INFLIGHT; - req->work.flags &= ~IO_WQ_WORK_FILES; - if (atomic_read(&tctx->in_idle)) - wake_up(&tctx->wait); + spin_unlock(&ctx->completion_lock); + return true; }

-static void __io_clean_op(struct io_kiocb *req) +static void io_clean_op(struct io_kiocb *req) { if (req->flags & REQ_F_BUFFER_SELECTED) { switch (req->opcode) { @@ -5965,7 +6487,6 @@ static void __io_clean_op(struct io_kiocb *req) kfree(req->sr_msg.kbuf); break; } - req->flags &= ~REQ_F_BUFFER_SELECTED; }

if (req->flags & REQ_F_NEED_CLEANUP) { @@ -5977,508 +6498,589 @@ static void __io_clean_op(struct io_kiocb *req) case IORING_OP_WRITE_FIXED: case IORING_OP_WRITE: { struct io_async_rw *io = req->async_data; - if (io->free_iovec) - kfree(io->free_iovec); + + kfree(io->free_iovec); break; } case IORING_OP_RECVMSG: case IORING_OP_SENDMSG: { struct io_async_msghdr *io = req->async_data; - if (io->iov != io->fast_iov) - kfree(io->iov); + + kfree(io->free_iov); break; } - case IORING_OP_SPLICE: - case IORING_OP_TEE: - io_put_file(req, req->splice.file_in, - (req->splice.flags & SPLICE_F_FD_IN_FIXED)); - break; case IORING_OP_OPENAT: case IORING_OP_OPENAT2: if (req->open.filename) putname(req->open.filename); break; + case IORING_OP_RENAMEAT: + putname(req->rename.oldpath); + putname(req->rename.newpath); + break; + case IORING_OP_UNLINKAT: + putname(req->unlink.filename); + break; } - req->flags &= ~REQ_F_NEED_CLEANUP; } + if ((req->flags & REQ_F_POLLED) && req->apoll) { + kfree(req->apoll->double_poll); + kfree(req->apoll); + req->apoll = NULL; + } + if (req->flags & REQ_F_INFLIGHT) { + struct io_uring_task *tctx = req->task->io_uring; + + atomic_dec(&tctx->inflight_tracked); + } + if (req->flags & REQ_F_CREDS) + put_cred(req->creds); + + req->flags &= ~IO_REQ_CLEAN_FLAGS; }

-static int io_issue_sqe(struct io_kiocb *req, bool force_nonblock, - struct io_comp_state *cs) +static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags) { struct io_ring_ctx *ctx = req->ctx; + const struct cred *creds = NULL; int ret;

+ if ((req->flags & REQ_F_CREDS) && req->creds != current_cred()) + creds = override_creds(req->creds); + switch (req->opcode) { case IORING_OP_NOP: - ret = io_nop(req, cs); + ret = io_nop(req, issue_flags); break; case IORING_OP_READV: case IORING_OP_READ_FIXED: case IORING_OP_READ: - ret = io_read(req, force_nonblock, cs); + ret = io_read(req, issue_flags); break; case IORING_OP_WRITEV: case IORING_OP_WRITE_FIXED: case IORING_OP_WRITE: - ret = io_write(req, force_nonblock, cs); + ret = io_write(req, issue_flags); break; case IORING_OP_FSYNC: - ret = io_fsync(req, force_nonblock); + ret = io_fsync(req, issue_flags); break; case IORING_OP_POLL_ADD: - ret = io_poll_add(req); + ret = io_poll_add(req, issue_flags); break; case IORING_OP_POLL_REMOVE: - ret = io_poll_remove(req); + ret = io_poll_update(req, issue_flags); break; case IORING_OP_SYNC_FILE_RANGE: - ret = io_sync_file_range(req, force_nonblock); + ret = io_sync_file_range(req, issue_flags); break; case IORING_OP_SENDMSG: - ret = io_sendmsg(req, force_nonblock, cs); + ret = io_sendmsg(req, issue_flags); break; case IORING_OP_SEND: - ret = io_send(req, force_nonblock, cs); + ret = io_send(req, issue_flags); break; case IORING_OP_RECVMSG: - ret = io_recvmsg(req, force_nonblock, cs); + ret = io_recvmsg(req, issue_flags); break; case IORING_OP_RECV: - ret = io_recv(req, force_nonblock, cs); + ret = io_recv(req, issue_flags); break; case IORING_OP_TIMEOUT: - ret = io_timeout(req); + ret = io_timeout(req, issue_flags); break; case IORING_OP_TIMEOUT_REMOVE: - ret = io_timeout_remove(req); + ret = io_timeout_remove(req, issue_flags); break; case IORING_OP_ACCEPT: - ret = io_accept(req, force_nonblock, cs); + ret = io_accept(req, issue_flags); break; case IORING_OP_CONNECT: - ret = io_connect(req, force_nonblock, cs); + ret = io_connect(req, issue_flags); break; case IORING_OP_ASYNC_CANCEL: - ret = io_async_cancel(req); + ret = io_async_cancel(req, issue_flags); break; case IORING_OP_FALLOCATE: - ret = io_fallocate(req, force_nonblock); + ret = io_fallocate(req, issue_flags); break; case IORING_OP_OPENAT: - ret = io_openat(req, force_nonblock); + ret = io_openat(req, issue_flags); break; case IORING_OP_CLOSE: - ret = io_close(req, force_nonblock, cs); + ret = io_close(req, issue_flags); break; case IORING_OP_FILES_UPDATE: - ret = io_files_update(req, force_nonblock, cs); + ret = io_files_update(req, issue_flags); break; case IORING_OP_STATX: - ret = io_statx(req, force_nonblock); + ret = io_statx(req, issue_flags); break; case IORING_OP_FADVISE: - ret = io_fadvise(req, force_nonblock); + ret = io_fadvise(req, issue_flags); break; case IORING_OP_MADVISE: - ret = io_madvise(req, force_nonblock); + ret = io_madvise(req, issue_flags); break; case IORING_OP_OPENAT2: - ret = io_openat2(req, force_nonblock); + ret = io_openat2(req, issue_flags); break; case IORING_OP_EPOLL_CTL: - ret = io_epoll_ctl(req, force_nonblock, cs); + ret = io_epoll_ctl(req, issue_flags); break; case IORING_OP_SPLICE: - ret = io_splice(req, force_nonblock); + ret = io_splice(req, issue_flags); break; case IORING_OP_PROVIDE_BUFFERS: - ret = io_provide_buffers(req, force_nonblock, cs); + ret = io_provide_buffers(req, issue_flags); break; case IORING_OP_REMOVE_BUFFERS: - ret = io_remove_buffers(req, force_nonblock, cs); + ret = io_remove_buffers(req, issue_flags); break; case IORING_OP_TEE: - ret = io_tee(req, force_nonblock); + ret = io_tee(req, issue_flags); + break; + case IORING_OP_SHUTDOWN: + ret = io_shutdown(req, issue_flags); + break; + case IORING_OP_RENAMEAT: + ret = io_renameat(req, issue_flags); + break; + case IORING_OP_UNLINKAT: + ret = io_unlinkat(req, issue_flags); break; default: ret = -EINVAL; break; }

+ if (creds) + revert_creds(creds); if (ret) return ret; - /* If the op doesn't have a file, we're not polling for it */ - if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file) { - const bool in_async = io_wq_current_is_worker(); - - /* workqueue context doesn't hold uring_lock, grab it now */ - if (in_async) - mutex_lock(&ctx->uring_lock); - + if ((ctx->flags & IORING_SETUP_IOPOLL) && req->file) io_iopoll_req_issued(req);

- if (in_async) - mutex_unlock(&ctx->uring_lock); - } - return 0; }

-static struct io_wq_work *io_wq_submit_work(struct io_wq_work *work) +static struct io_wq_work *io_wq_free_work(struct io_wq_work *work) +{ + struct io_kiocb *req = container_of(work, struct io_kiocb, work); + + req = io_put_req_find_next(req); + return req ? &req->work : NULL; +} + +static void io_wq_submit_work(struct io_wq_work *work) { struct io_kiocb *req = container_of(work, struct io_kiocb, work); struct io_kiocb *timeout; int ret = 0;

+ /* one will be dropped by ->io_free_work() after returning to io-wq */ + if (!(req->flags & REQ_F_REFCOUNT)) + __io_req_set_refcount(req, 2); + else + req_ref_get(req); + timeout = io_prep_linked_timeout(req); if (timeout) io_queue_linked_timeout(timeout);

- /* if NO_CANCEL is set, we must still run the work */ - if ((work->flags & (IO_WQ_WORK_CANCEL|IO_WQ_WORK_NO_CANCEL)) == - IO_WQ_WORK_CANCEL) { + /* either cancelled or io-wq is dying, so don't touch tctx->iowq */ + if (work->flags & IO_WQ_WORK_CANCEL) ret = -ECANCELED; - }

if (!ret) { do { - ret = io_issue_sqe(req, false, NULL); + ret = io_issue_sqe(req, 0); /* * We can get EAGAIN for polled IO even though we're * forcing a sync submission from here, since we can't * wait for request slots on the block side. */ - if (ret != -EAGAIN) + if (ret != -EAGAIN || !(req->ctx->flags & IORING_SETUP_IOPOLL)) break; cond_resched(); } while (1); }

- if (ret) { - struct io_ring_ctx *lock_ctx = NULL; - - if (req->ctx->flags & IORING_SETUP_IOPOLL) - lock_ctx = req->ctx; - - /* - * io_iopoll_complete() does not hold completion_lock to - * complete polled io, so here for polled io, we can not call - * io_req_complete() directly, otherwise there maybe concurrent - * access to cqring, defer_list, etc, which is not safe. Given - * that io_iopoll_complete() is always called under uring_lock, - * so here for polled io, we also get uring_lock to complete - * it. - */ - if (lock_ctx) - mutex_lock(&lock_ctx->uring_lock); - - req_set_fail_links(req); - io_req_complete(req, ret); - - if (lock_ctx) - mutex_unlock(&lock_ctx->uring_lock); - } + /* avoid locking problems by failing it from a clean context */ + if (ret) + io_req_task_queue_fail(req, ret); +}

- return io_steal_work(req); +static inline struct io_fixed_file *io_fixed_file_slot(struct io_file_table *table, + unsigned i) +{ + return &table->files[i]; }

static inline struct file *io_file_from_index(struct io_ring_ctx *ctx, int index) { - struct fixed_file_table *table; + struct io_fixed_file *slot = io_fixed_file_slot(&ctx->file_table, index);

- table = &ctx->file_data->table[index >> IORING_FILE_TABLE_SHIFT]; - return table->files[index & IORING_FILE_TABLE_MASK]; + return (struct file *) (slot->file_ptr & FFS_MASK); }

-static struct file *io_file_get(struct io_submit_state *state, - struct io_kiocb *req, int fd, bool fixed) +static void io_fixed_file_set(struct io_fixed_file *file_slot, struct file *file) +{ + unsigned long file_ptr = (unsigned long) file; + + if (__io_file_supports_nowait(file, READ)) + file_ptr |= FFS_ASYNC_READ; + if (__io_file_supports_nowait(file, WRITE)) + file_ptr |= FFS_ASYNC_WRITE; + if (S_ISREG(file_inode(file)->i_mode)) + file_ptr |= FFS_ISREG; + file_slot->file_ptr = file_ptr; +} + +static inline struct file *io_file_get_fixed(struct io_ring_ctx *ctx, + struct io_kiocb *req, int fd) { - struct io_ring_ctx *ctx = req->ctx; struct file *file; + unsigned long file_ptr;

- if (fixed) { - if (unlikely((unsigned int)fd >= ctx->nr_user_files)) - return NULL; - fd = array_index_nospec(fd, ctx->nr_user_files); - file = io_file_from_index(ctx, fd); - if (file) { - req->fixed_file_refs = &ctx->file_data->node->refs; - percpu_ref_get(req->fixed_file_refs); - } - } else { - trace_io_uring_file_get(ctx, fd); - file = __io_file_get(state, fd); - } + if (unlikely((unsigned int)fd >= ctx->nr_user_files)) + return NULL; + fd = array_index_nospec(fd, ctx->nr_user_files); + file_ptr = io_fixed_file_slot(&ctx->file_table, fd)->file_ptr; + file = (struct file *) (file_ptr & FFS_MASK); + file_ptr &= ~FFS_MASK; + /* mask in overlapping REQ_F and FFS bits */ + req->flags |= (file_ptr << REQ_F_NOWAIT_READ_BIT); + io_req_set_rsrc_node(req); + return file; +}

- if (file && file->f_op == &io_uring_fops && - !(req->flags & REQ_F_INFLIGHT)) { - io_req_init_async(req); - req->flags |= REQ_F_INFLIGHT; +static struct file *io_file_get_normal(struct io_ring_ctx *ctx, + struct io_kiocb *req, int fd) +{ + struct file *file = fget(fd);

- spin_lock_irq(&ctx->inflight_lock); - list_add(&req->inflight_entry, &ctx->inflight_list); - spin_unlock_irq(&ctx->inflight_lock); - } + trace_io_uring_file_get(ctx, fd);

+ /* we don't allow fixed io_uring files */ + if (file && unlikely(file->f_op == &io_uring_fops)) + io_req_track_inflight(req); return file; }

-static int io_req_set_file(struct io_submit_state *state, struct io_kiocb *req, - int fd) +static inline struct file *io_file_get(struct io_ring_ctx *ctx, + struct io_kiocb *req, int fd, bool fixed) { - bool fixed; + if (fixed) + return io_file_get_fixed(ctx, req, fd); + else + return io_file_get_normal(ctx, req, fd); +}

- fixed = (req->flags & REQ_F_FIXED_FILE) != 0; - if (unlikely(!fixed && io_async_submit(req->ctx))) - return -EBADF; +static void io_req_task_link_timeout(struct io_kiocb *req, bool *locked) +{ + struct io_kiocb *prev = req->timeout.prev; + int ret = -ENOENT;

- req->file = io_file_get(state, req, fd, fixed); - if (req->file || io_op_defs[req->opcode].needs_file_no_error) - return 0; - return -EBADF; + if (prev) { + if (!(req->task->flags & PF_EXITING)) + ret = io_try_cancel_userdata(req, prev->user_data); + io_req_complete_post(req, ret ?: -ETIME, 0); + io_put_req(prev); + } else { + io_req_complete_post(req, -ETIME, 0); + } }

static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer) { struct io_timeout_data *data = container_of(timer, struct io_timeout_data, timer); - struct io_kiocb *req = data->req; + struct io_kiocb *prev, *req = data->req; struct io_ring_ctx *ctx = req->ctx; - struct io_kiocb *prev = NULL; unsigned long flags;

- spin_lock_irqsave(&ctx->completion_lock, flags); + spin_lock_irqsave(&ctx->timeout_lock, flags); + prev = req->timeout.head; + req->timeout.head = NULL;

/* * We don't expect the list to be empty, that will only happen if we * race with the completion of the linked work. */ - if (!list_empty(&req->link_list)) { - prev = list_entry(req->link_list.prev, struct io_kiocb, - link_list); - list_del_init(&req->link_list); - if (!refcount_inc_not_zero(&prev->refs)) + if (prev) { + io_remove_next_linked(prev); + if (!req_ref_inc_not_zero(prev)) prev = NULL; } - list_del(&req->timeout.list); - spin_unlock_irqrestore(&ctx->completion_lock, flags); + req->timeout.prev = prev; + spin_unlock_irqrestore(&ctx->timeout_lock, flags);

- if (prev) { - io_async_find_and_cancel(ctx, req, prev->user_data, -ETIME); - io_put_req_deferred(prev, 1); - } else { - io_cqring_add_event(req, -ETIME, 0); - io_put_req_deferred(req, 1); - } + req->io_task_work.func = io_req_task_link_timeout; + io_req_task_work_add(req); return HRTIMER_NORESTART; }

-static void __io_queue_linked_timeout(struct io_kiocb *req) +static void io_queue_linked_timeout(struct io_kiocb *req) { + struct io_ring_ctx *ctx = req->ctx; + + spin_lock_irq(&ctx->timeout_lock); /* - * If the list is now empty, then our linked request finished before - * we got a chance to setup the timer + * If the back reference is NULL, then our linked request finished + * before we got a chance to setup the timer */ - if (!list_empty(&req->link_list)) { + if (req->timeout.head) { struct io_timeout_data *data = req->async_data;

data->timer.function = io_link_timeout_fn; hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode); + list_add_tail(&req->timeout.list, &ctx->ltimeout_list); } -} - -static void io_queue_linked_timeout(struct io_kiocb *req) -{ - struct io_ring_ctx *ctx = req->ctx; - - spin_lock_irq(&ctx->completion_lock); - __io_queue_linked_timeout(req); - spin_unlock_irq(&ctx->completion_lock); - + spin_unlock_irq(&ctx->timeout_lock); /* drop submission reference */ io_put_req(req); }

-static struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req) -{ - struct io_kiocb *nxt; - - if (!(req->flags & REQ_F_LINK_HEAD)) - return NULL; - if (req->flags & REQ_F_LINK_TIMEOUT) - return NULL; - - nxt = list_first_entry_or_null(&req->link_list, struct io_kiocb, - link_list); - if (!nxt || nxt->opcode != IORING_OP_LINK_TIMEOUT) - return NULL; - - nxt->flags |= REQ_F_LTIMEOUT_ACTIVE; - req->flags |= REQ_F_LINK_TIMEOUT; - return nxt; -} - -static void __io_queue_sqe(struct io_kiocb *req, struct io_comp_state *cs) +static void __io_queue_sqe(struct io_kiocb *req) + __must_hold(&req->ctx->uring_lock) { struct io_kiocb *linked_timeout; - const struct cred *old_creds = NULL; int ret;

-again: - linked_timeout = io_prep_linked_timeout(req); - - if ((req->flags & REQ_F_WORK_INITIALIZED) && - (req->work.flags & IO_WQ_WORK_CREDS) && - req->work.identity->creds != current_cred()) { - if (old_creds) - revert_creds(old_creds); - if (old_creds == req->work.identity->creds) - old_creds = NULL; /* restored original creds */ - else - old_creds = override_creds(req->work.identity->creds); - } - - ret = io_issue_sqe(req, true, cs); +issue_sqe: + ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);

/* * We async punt it if the file wasn't marked NOWAIT, or if the file * doesn't support non-blocking read/write attempts */ - if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) { - if (!io_arm_poll_handler(req)) { + if (likely(!ret)) { + if (req->flags & REQ_F_COMPLETE_INLINE) { + struct io_ring_ctx *ctx = req->ctx; + struct io_submit_state *state = &ctx->submit_state; + + state->compl_reqs[state->compl_nr++] = req; + if (state->compl_nr == ARRAY_SIZE(state->compl_reqs)) + io_submit_flush_completions(ctx); + return; + } + + linked_timeout = io_prep_linked_timeout(req); + if (linked_timeout) + io_queue_linked_timeout(linked_timeout); + } else if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) { + linked_timeout = io_prep_linked_timeout(req); + + switch (io_arm_poll_handler(req)) { + case IO_APOLL_READY: + if (linked_timeout) + io_queue_linked_timeout(linked_timeout); + goto issue_sqe; + case IO_APOLL_ABORTED: /* * Queued up for async execution, worker will release * submit reference when the iocb is actually submitted. */ - io_queue_async_work(req); + io_queue_async_work(req, NULL); + break; }

if (linked_timeout) io_queue_linked_timeout(linked_timeout); - } else if (likely(!ret)) { - /* drop submission reference */ - req = io_put_req_find_next(req); - if (linked_timeout) - io_queue_linked_timeout(linked_timeout); - - if (req) { - if (!(req->flags & REQ_F_FORCE_ASYNC)) - goto again; - io_queue_async_work(req); - } } else { - /* un-prep timeout, so it'll be killed as any other linked */ - req->flags &= ~REQ_F_LINK_TIMEOUT; - req_set_fail_links(req); - io_put_req(req); - io_req_complete(req, ret); + io_req_complete_failed(req, ret); } - - if (old_creds) - revert_creds(old_creds); }

-static void io_queue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, - struct io_comp_state *cs) +static inline void io_queue_sqe(struct io_kiocb *req) + __must_hold(&req->ctx->uring_lock) { - int ret; + if (unlikely(req->ctx->drain_active) && io_drain_req(req)) + return;

- ret = io_req_defer(req, sqe); - if (ret) { - if (ret != -EIOCBQUEUED) { -fail_req: - req_set_fail_links(req); - io_put_req(req); - io_req_complete(req, ret); - } - } else if (req->flags & REQ_F_FORCE_ASYNC) { - if (!req->async_data) { - ret = io_req_defer_prep(req, sqe); - if (unlikely(ret)) - goto fail_req; - } - io_queue_async_work(req); + if (likely(!(req->flags & (REQ_F_FORCE_ASYNC | REQ_F_FAIL)))) { + __io_queue_sqe(req); + } else if (req->flags & REQ_F_FAIL) { + io_req_complete_fail_submit(req); } else { - if (sqe) { - ret = io_req_prep(req, sqe); - if (unlikely(ret)) - goto fail_req; - } - __io_queue_sqe(req, cs); + int ret = io_req_prep_async(req); + + if (unlikely(ret)) + io_req_complete_failed(req, ret); + else + io_queue_async_work(req, NULL); } }

-static inline void io_queue_link_head(struct io_kiocb *req, - struct io_comp_state *cs) +/* + * Check SQE restrictions (opcode and flags). + * + * Returns 'true' if SQE is allowed, 'false' otherwise. + */ +static inline bool io_check_restriction(struct io_ring_ctx *ctx, + struct io_kiocb *req, + unsigned int sqe_flags) { - if (unlikely(req->flags & REQ_F_FAIL_LINK)) { - io_put_req(req); - io_req_complete(req, -ECANCELED); - } else - io_queue_sqe(req, NULL, cs); -} + if (likely(!ctx->restricted)) + return true;

-static int io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, - struct io_kiocb **link, struct io_comp_state *cs) -{ - struct io_ring_ctx *ctx = req->ctx; - int ret; + if (!test_bit(req->opcode, ctx->restrictions.sqe_op)) + return false;

- /* - * If we already have a head request, queue this one for async - * submittal once the head completes. If we don't have a head but - * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be - * submitted sync once the chain is complete. If none of those - * conditions are true (normal request), then just queue it. - */ - if (*link) { - struct io_kiocb *head = *link; + if ((sqe_flags & ctx->restrictions.sqe_flags_required) != + ctx->restrictions.sqe_flags_required) + return false;

- /* - * Taking sequential execution of a link, draining both sides - * of the link also fullfils IOSQE_IO_DRAIN semantics for all - * requests in the link. So, it drains the head and the - * next after the link request. The last one is done via - * drain_next flag to persist the effect across calls. - */ - if (req->flags & REQ_F_IO_DRAIN) { - head->flags |= REQ_F_IO_DRAIN; - ctx->drain_next = 1; - } - ret = io_req_defer_prep(req, sqe); - if (unlikely(ret)) { - /* fail even hard links since we don't submit */ - head->flags |= REQ_F_FAIL_LINK; - return ret; - } - trace_io_uring_link(ctx, req, head); - list_add_tail(&req->link_list, &head->link_list); + if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed | + ctx->restrictions.sqe_flags_required)) + return false;

- /* last request of a link, enqueue the link */ - if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) { - io_queue_link_head(head, cs); - *link = NULL; + return true; +} + +static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, + const struct io_uring_sqe *sqe) + __must_hold(&ctx->uring_lock) +{ + struct io_submit_state *state; + unsigned int sqe_flags; + int personality, ret = 0; + + /* req is partially pre-initialised, see io_preinit_req() */ + req->opcode = READ_ONCE(sqe->opcode); + /* same numerical values with corresponding REQ_F_*, safe to copy */ + req->flags = sqe_flags = READ_ONCE(sqe->flags); + req->user_data = READ_ONCE(sqe->user_data); + req->file = NULL; + req->fixed_rsrc_refs = NULL; + req->task = current; + + /* enforce forwards compatibility on users */ + if (unlikely(sqe_flags & ~SQE_VALID_FLAGS)) + return -EINVAL; + if (unlikely(req->opcode >= IORING_OP_LAST)) + return -EINVAL; + if (!io_check_restriction(ctx, req, sqe_flags)) + return -EACCES; + + if ((sqe_flags & IOSQE_BUFFER_SELECT) && + !io_op_defs[req->opcode].buffer_select) + return -EOPNOTSUPP; + if (unlikely(sqe_flags & IOSQE_IO_DRAIN)) + ctx->drain_active = true; + + personality = READ_ONCE(sqe->personality); + if (personality) { + req->creds = xa_load(&ctx->personalities, personality); + if (!req->creds) + return -EINVAL; + get_cred(req->creds); + req->flags |= REQ_F_CREDS; + } + state = &ctx->submit_state; + + /* + * Plug now if we have more than 1 IO left after this, and the target + * is potentially a read/write to block based storage. + */ + if (!state->plug_started && state->ios_left > 1 && + io_op_defs[req->opcode].plug) { + blk_start_plug(&state->plug); + state->plug_started = true; + } + + if (io_op_defs[req->opcode].needs_file) { + req->file = io_file_get(ctx, req, READ_ONCE(sqe->fd), + (sqe_flags & IOSQE_FIXED_FILE)); + if (unlikely(!req->file)) + ret = -EBADF; + } + + state->ios_left--; + return ret; +} + +static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req, + const struct io_uring_sqe *sqe) + __must_hold(&ctx->uring_lock) +{ + struct io_submit_link *link = &ctx->submit_state.link; + int ret; + + ret = io_init_req(ctx, req, sqe); + if (unlikely(ret)) { +fail_req: + /* fail even hard links since we don't submit */ + if (link->head) { + /* + * we can judge a link req is failed or cancelled by if + * REQ_F_FAIL is set, but the head is an exception since + * it may be set REQ_F_FAIL because of other req's failure + * so let's leverage req->result to distinguish if a head + * is set REQ_F_FAIL because of its failure or other req's + * failure so that we can set the correct ret code for it. + * init result here to avoid affecting the normal path. + */ + if (!(link->head->flags & REQ_F_FAIL)) + req_fail_link_node(link->head, -ECANCELED); + } else if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) { + /* + * the current req is a normal req, we should return + * error and thus break the submittion loop. + */ + io_req_complete_failed(req, ret); + return ret; } + req_fail_link_node(req, ret); } else { - if (unlikely(ctx->drain_next)) { - req->flags |= REQ_F_IO_DRAIN; - ctx->drain_next = 0; + ret = io_req_prep(req, sqe); + if (unlikely(ret)) + goto fail_req; + } + + /* don't need @sqe from now on */ + trace_io_uring_submit_sqe(ctx, req, req->opcode, req->user_data, + req->flags, true, + ctx->flags & IORING_SETUP_SQPOLL); + + /* + * If we already have a head request, queue this one for async + * submittal once the head completes. If we don't have a head but + * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be + * submitted sync once the chain is complete. If none of those + * conditions are true (normal request), then just queue it. + */ + if (link->head) { + struct io_kiocb *head = link->head; + + if (!(req->flags & REQ_F_FAIL)) { + ret = io_req_prep_async(req); + if (unlikely(ret)) { + req_fail_link_node(req, ret); + if (!(head->flags & REQ_F_FAIL)) + req_fail_link_node(head, -ECANCELED); + } } - if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) { - req->flags |= REQ_F_LINK_HEAD; - INIT_LIST_HEAD(&req->link_list); + trace_io_uring_link(ctx, req, head); + link->last->link = req; + link->last = req;

- ret = io_req_defer_prep(req, sqe); - if (unlikely(ret)) - req->flags |= REQ_F_FAIL_LINK; - *link = req; + /* last request of a link, enqueue the link */ + if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) { + link->head = NULL; + io_queue_sqe(head); + } + } else { + if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) { + link->head = req; + link->last = req; } else { - io_queue_sqe(req, sqe, cs); + io_queue_sqe(req); } }

@@ -6488,29 +7090,27 @@ static int io_submit_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, /* * Batched submission is done, ensure local IO is flushed out. */ -static void io_submit_state_end(struct io_submit_state *state) +static void io_submit_state_end(struct io_submit_state *state, + struct io_ring_ctx *ctx) { - if (!list_empty(&state->comp.list)) - io_submit_flush_completions(&state->comp); - blk_finish_plug(&state->plug); - io_state_file_put(state); - if (state->free_reqs) - kmem_cache_free_bulk(req_cachep, state->free_reqs, state->reqs); + if (state->link.head) + io_queue_sqe(state->link.head); + if (state->compl_nr) + io_submit_flush_completions(ctx); + if (state->plug_started) + blk_finish_plug(&state->plug); }

/* * Start submission side cache. */ static void io_submit_state_start(struct io_submit_state *state, - struct io_ring_ctx *ctx, unsigned int max_ios) -{ - blk_start_plug(&state->plug); - state->comp.nr = 0; - INIT_LIST_HEAD(&state->comp.list); - state->comp.ctx = ctx; - state->free_reqs = 0; - state->file = NULL; + unsigned int max_ios) +{ + state->plug_started = false; state->ios_left = max_ios; + /* set only head, no need to init link_last in advance */ + state->link.head = NULL; }

static void io_commit_sqring(struct io_ring_ctx *ctx) @@ -6526,7 +7126,7 @@ static void io_commit_sqring(struct io_ring_ctx *ctx) }

/* - * Fetch an sqe, if one is available. Note that sqe_ptr will point to memory + * Fetch an sqe, if one is available. Note this returns a pointer to memory * that is mapped by userspace. This means that care needs to be taken to * ensure that reads are stable, as we cannot rely on userspace always * being a good citizen. If members of the sqe are validated and then later @@ -6535,8 +7135,8 @@ static void io_commit_sqring(struct io_ring_ctx *ctx) */ static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx) { - u32 *sq_array = ctx->sq_array; - unsigned head; + unsigned head, mask = ctx->sq_entries - 1; + unsigned sq_idx = ctx->cached_sq_head++ & mask;

/* * The cached sq head (or cq tail) serves two purposes: @@ -6546,423 +7146,256 @@ static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx) * 2) allows the kernel side to track the head on its own, even * though the application is the one updating it. */ - head = READ_ONCE(sq_array[ctx->cached_sq_head & ctx->sq_mask]); + head = READ_ONCE(ctx->sq_array[sq_idx]); if (likely(head < ctx->sq_entries)) return &ctx->sq_sqes[head];

/* drop invalid entries */ - ctx->cached_sq_dropped++; - WRITE_ONCE(ctx->rings->sq_dropped, ctx->cached_sq_dropped); + ctx->cq_extra--; + WRITE_ONCE(ctx->rings->sq_dropped, + READ_ONCE(ctx->rings->sq_dropped) + 1); return NULL; }

-static inline void io_consume_sqe(struct io_ring_ctx *ctx) -{ - ctx->cached_sq_head++; -} - -/* - * Check SQE restrictions (opcode and flags). - * - * Returns 'true' if SQE is allowed, 'false' otherwise. - */ -static inline bool io_check_restriction(struct io_ring_ctx *ctx, - struct io_kiocb *req, - unsigned int sqe_flags) -{ - if (!ctx->restricted) - return true; - - if (!test_bit(req->opcode, ctx->restrictions.sqe_op)) - return false; - - if ((sqe_flags & ctx->restrictions.sqe_flags_required) != - ctx->restrictions.sqe_flags_required) - return false; - - if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed | - ctx->restrictions.sqe_flags_required)) - return false; - - return true; -} - -#define SQE_VALID_FLAGS (IOSQE_FIXED_FILE|IOSQE_IO_DRAIN|IOSQE_IO_LINK| \ - IOSQE_IO_HARDLINK | IOSQE_ASYNC | \ - IOSQE_BUFFER_SELECT) - -static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, - const struct io_uring_sqe *sqe, - struct io_submit_state *state) -{ - unsigned int sqe_flags; - int id, ret; - - req->opcode = READ_ONCE(sqe->opcode); - req->user_data = READ_ONCE(sqe->user_data); - req->async_data = NULL; - req->file = NULL; - req->ctx = ctx; - req->flags = 0; - /* one is dropped after submission, the other at completion */ - refcount_set(&req->refs, 2); - req->task = current; - req->result = 0; - - if (unlikely(req->opcode >= IORING_OP_LAST)) - return -EINVAL; - - if (unlikely(io_sq_thread_acquire_mm(ctx, req))) - return -EFAULT; - - sqe_flags = READ_ONCE(sqe->flags); - /* enforce forwards compatibility on users */ - if (unlikely(sqe_flags & ~SQE_VALID_FLAGS)) - return -EINVAL; - - if (unlikely(!io_check_restriction(ctx, req, sqe_flags))) - return -EACCES; - - if ((sqe_flags & IOSQE_BUFFER_SELECT) && - !io_op_defs[req->opcode].buffer_select) - return -EOPNOTSUPP; - - id = READ_ONCE(sqe->personality); - if (id) { - struct io_identity *iod; - - iod = xa_load(&ctx->personalities, id); - if (unlikely(!iod)) - return -EINVAL; - refcount_inc(&iod->count); - - __io_req_init_async(req); - get_cred(iod->creds); - req->work.identity = iod; - req->work.flags |= IO_WQ_WORK_CREDS; - } - - /* same numerical values with corresponding REQ_F_*, safe to copy */ - req->flags |= sqe_flags; - - if (!io_op_defs[req->opcode].needs_file) - return 0; - - ret = io_req_set_file(state, req, READ_ONCE(sqe->fd)); - state->ios_left--; - return ret; -} - static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) + __must_hold(&ctx->uring_lock) { - struct io_submit_state state; - struct io_kiocb *link = NULL; - int i, submitted = 0; - - /* if we have a backlog and couldn't flush it all, return BUSY */ - if (test_bit(0, &ctx->sq_check_overflow)) { - if (!__io_cqring_overflow_flush(ctx, false, NULL, NULL)) - return -EBUSY; - } + int submitted = 0;

/* make sure SQ entry isn't read before tail */ nr = min3(nr, ctx->sq_entries, io_sqring_entries(ctx)); - if (!percpu_ref_tryget_many(&ctx->refs, nr)) return -EAGAIN; + io_get_task_refs(nr);

- percpu_counter_add(&current->io_uring->inflight, nr); - refcount_add(nr, &current->usage); - - io_submit_state_start(&state, ctx, nr); - - for (i = 0; i < nr; i++) { + io_submit_state_start(&ctx->submit_state, nr); + while (submitted < nr) { const struct io_uring_sqe *sqe; struct io_kiocb *req; - int err;

- sqe = io_get_sqe(ctx); - if (unlikely(!sqe)) { - io_consume_sqe(ctx); - break; - } - req = io_alloc_req(ctx, &state); + req = io_alloc_req(ctx); if (unlikely(!req)) { if (!submitted) submitted = -EAGAIN; break; } - io_consume_sqe(ctx); + sqe = io_get_sqe(ctx); + if (unlikely(!sqe)) { + list_add(&req->inflight_entry, &ctx->submit_state.free_list); + break; + } /* will complete beyond this point, count as submitted */ submitted++; - - err = io_init_req(ctx, req, sqe, &state); - if (unlikely(err)) { -fail_req: - io_put_req(req); - io_req_complete(req, err); + if (io_submit_sqe(ctx, req, sqe)) break; - } - - trace_io_uring_submit_sqe(ctx, req->opcode, req->user_data, - true, io_async_submit(ctx)); - err = io_submit_sqe(req, sqe, &link, &state.comp); - if (err) - goto fail_req; }

if (unlikely(submitted != nr)) { int ref_used = (submitted == -EAGAIN) ? 0 : submitted; - struct io_uring_task *tctx = current->io_uring; int unused = nr - ref_used;

+ current->io_uring->cached_refs += unused; percpu_ref_put_many(&ctx->refs, unused); - percpu_counter_sub(&tctx->inflight, unused); - put_task_struct_many(current, unused); } - if (link) - io_queue_link_head(link, &state.comp); - io_submit_state_end(&state);

+ io_submit_state_end(&ctx->submit_state, ctx); /* Commit SQ ring head once we've consumed and submitted all SQEs */ io_commit_sqring(ctx);

return submitted; }

-static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx) +static inline bool io_sqd_events_pending(struct io_sq_data *sqd) { - /* Tell userspace we may need a wakeup call */ - spin_lock_irq(&ctx->completion_lock); - ctx->rings->sq_flags |= IORING_SQ_NEED_WAKEUP; - spin_unlock_irq(&ctx->completion_lock); + return READ_ONCE(sqd->state); }

-static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx) +static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx) { - spin_lock_irq(&ctx->completion_lock); - ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP; - spin_unlock_irq(&ctx->completion_lock); + /* Tell userspace we may need a wakeup call */ + spin_lock(&ctx->completion_lock); + WRITE_ONCE(ctx->rings->sq_flags, + ctx->rings->sq_flags | IORING_SQ_NEED_WAKEUP); + spin_unlock(&ctx->completion_lock); }

-static int io_sq_wake_function(struct wait_queue_entry *wqe, unsigned mode, - int sync, void *key) +static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx) { - struct io_ring_ctx *ctx = container_of(wqe, struct io_ring_ctx, sqo_wait_entry); - int ret; - - ret = autoremove_wake_function(wqe, mode, sync, key); - if (ret) { - unsigned long flags; - - spin_lock_irqsave(&ctx->completion_lock, flags); - ctx->rings->sq_flags &= ~IORING_SQ_NEED_WAKEUP; - spin_unlock_irqrestore(&ctx->completion_lock, flags); - } - return ret; + spin_lock(&ctx->completion_lock); + WRITE_ONCE(ctx->rings->sq_flags, + ctx->rings->sq_flags & ~IORING_SQ_NEED_WAKEUP); + spin_unlock(&ctx->completion_lock); }

-enum sq_ret { - SQT_IDLE = 1, - SQT_SPIN = 2, - SQT_DID_WORK = 4, -}; - -static enum sq_ret __io_sq_thread(struct io_ring_ctx *ctx, - unsigned long start_jiffies, bool cap_entries) +static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries) { - unsigned long timeout = start_jiffies + ctx->sq_thread_idle; - struct io_sq_data *sqd = ctx->sq_data; unsigned int to_submit; int ret = 0;

-again: - if (!list_empty(&ctx->iopoll_list)) { - unsigned nr_events = 0; - - mutex_lock(&ctx->uring_lock); - if (!list_empty(&ctx->iopoll_list) && !need_resched()) - io_do_iopoll(ctx, &nr_events, 0); - mutex_unlock(&ctx->uring_lock); - } - to_submit = io_sqring_entries(ctx); + /* if we're handling multiple rings, cap submit size for fairness */ + if (cap_entries && to_submit > IORING_SQPOLL_CAP_ENTRIES_VALUE) + to_submit = IORING_SQPOLL_CAP_ENTRIES_VALUE;

- /* - * If submit got -EBUSY, flag us as needing the application - * to enter the kernel to reap and flush events. - */ - if (!to_submit || ret == -EBUSY || need_resched()) { - /* - * Drop cur_mm before scheduling, we can't hold it for - * long periods (or over schedule()). Do this before - * adding ourselves to the waitqueue, as the unuse/drop - * may sleep. - */ - io_sq_thread_drop_mm(); + if (!list_empty(&ctx->iopoll_list) || to_submit) { + unsigned nr_events = 0; + const struct cred *creds = NULL;

- /* - * We're polling. If we're within the defined idle - * period, then let us spin without work before going - * to sleep. The exception is if we got EBUSY doing - * more IO, we should wait for the application to - * reap events and wake us up. - */ - if (!list_empty(&ctx->iopoll_list) || need_resched() || - (!time_after(jiffies, timeout) && ret != -EBUSY && - !percpu_ref_is_dying(&ctx->refs))) - return SQT_SPIN; + if (ctx->sq_creds != current_cred()) + creds = override_creds(ctx->sq_creds);

- prepare_to_wait(&sqd->wait, &ctx->sqo_wait_entry, - TASK_INTERRUPTIBLE); + mutex_lock(&ctx->uring_lock); + if (!list_empty(&ctx->iopoll_list)) + io_do_iopoll(ctx, &nr_events, 0);

/* - * While doing polled IO, before going to sleep, we need - * to check if there are new reqs added to iopoll_list, - * it is because reqs may have been punted to io worker - * and will be added to iopoll_list later, hence check - * the iopoll_list again. + * Don't submit if refs are dying, good for io_uring_register(), + * but also it is relied upon by io_ring_exit_work() */ - if ((ctx->flags & IORING_SETUP_IOPOLL) && - !list_empty_careful(&ctx->iopoll_list)) { - finish_wait(&sqd->wait, &ctx->sqo_wait_entry); - goto again; - } + if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) && + !(ctx->flags & IORING_SETUP_R_DISABLED)) + ret = io_submit_sqes(ctx, to_submit); + mutex_unlock(&ctx->uring_lock);

- to_submit = io_sqring_entries(ctx); - if (!to_submit || ret == -EBUSY) - return SQT_IDLE; + if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait)) + wake_up(&ctx->sqo_sq_wait); + if (creds) + revert_creds(creds); }

- finish_wait(&sqd->wait, &ctx->sqo_wait_entry); - io_ring_clear_wakeup_flag(ctx); - - /* if we're handling multiple rings, cap submit size for fairness */ - if (cap_entries && to_submit > 8) - to_submit = 8; - - mutex_lock(&ctx->uring_lock); - if (likely(!percpu_ref_is_dying(&ctx->refs) && !ctx->sqo_dead)) - ret = io_submit_sqes(ctx, to_submit); - mutex_unlock(&ctx->uring_lock); + return ret; +}

- if (!io_sqring_full(ctx) && wq_has_sleeper(&ctx->sqo_sq_wait)) - wake_up(&ctx->sqo_sq_wait); +static void io_sqd_update_thread_idle(struct io_sq_data *sqd) +{ + struct io_ring_ctx *ctx; + unsigned sq_thread_idle = 0;

- return SQT_DID_WORK; + list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) + sq_thread_idle = max(sq_thread_idle, ctx->sq_thread_idle); + sqd->sq_thread_idle = sq_thread_idle; }

-static void io_sqd_init_new(struct io_sq_data *sqd) +static bool io_sqd_handle_event(struct io_sq_data *sqd) { - struct io_ring_ctx *ctx; + bool did_sig = false; + struct ksignal ksig;

- while (!list_empty(&sqd->ctx_new_list)) { - ctx = list_first_entry(&sqd->ctx_new_list, struct io_ring_ctx, sqd_list); - init_wait(&ctx->sqo_wait_entry); - ctx->sqo_wait_entry.func = io_sq_wake_function; - list_move_tail(&ctx->sqd_list, &sqd->ctx_list); - complete(&ctx->sq_thread_comp); + if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) || + signal_pending(current)) { + mutex_unlock(&sqd->lock); + if (signal_pending(current)) + did_sig = get_signal(&ksig); + cond_resched(); + mutex_lock(&sqd->lock); } + return did_sig || test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state); }

static int io_sq_thread(void *data) { - struct cgroup_subsys_state *cur_css = NULL; - const struct cred *old_cred = NULL; struct io_sq_data *sqd = data; struct io_ring_ctx *ctx; - unsigned long start_jiffies; + unsigned long timeout = 0; + char buf[TASK_COMM_LEN]; + DEFINE_WAIT(wait);

- start_jiffies = jiffies; - while (!kthread_should_stop()) { - enum sq_ret ret = 0; - bool cap_entries; + snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid); + set_task_comm(current, buf);

- /* - * Any changes to the sqd lists are synchronized through the - * kthread parking. This synchronizes the thread vs users, - * the users are synchronized on the sqd->ctx_lock. - */ - if (kthread_should_park()) { - kthread_parkme(); - /* - * When sq thread is unparked, in case the previous park operation - * comes from io_put_sq_data(), which means that sq thread is going - * to be stopped, so here needs to have a check. - */ - if (kthread_should_stop()) + if (sqd->sq_cpu != -1) + set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu)); + else + set_cpus_allowed_ptr(current, cpu_online_mask); + current->flags |= PF_NO_SETAFFINITY; + + mutex_lock(&sqd->lock); + while (1) { + bool cap_entries, sqt_spin = false; + + if (io_sqd_events_pending(sqd) || signal_pending(current)) { + if (io_sqd_handle_event(sqd)) break; + timeout = jiffies + sqd->sq_thread_idle; }

- if (unlikely(!list_empty(&sqd->ctx_new_list))) - io_sqd_init_new(sqd); - cap_entries = !list_is_singular(&sqd->ctx_list); - list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) { - if (current->cred != ctx->creds) { - if (old_cred) - revert_creds(old_cred); - old_cred = override_creds(ctx->creds); - } - io_sq_thread_associate_blkcg(ctx, &cur_css); -#ifdef CONFIG_AUDIT - current->loginuid = ctx->loginuid; - current->sessionid = ctx->sessionid; -#endif + int ret = __io_sq_thread(ctx, cap_entries);

- ret |= __io_sq_thread(ctx, start_jiffies, cap_entries); - - io_sq_thread_drop_mm(); + if (!sqt_spin && (ret > 0 || !list_empty(&ctx->iopoll_list))) + sqt_spin = true; } + if (io_run_task_work()) + sqt_spin = true;

- if (ret & SQT_SPIN) { - io_run_task_work(); - io_sq_thread_drop_mm(); + if (sqt_spin || !time_after(jiffies, timeout)) { cond_resched(); - } else if (ret == SQT_IDLE) { - if (kthread_should_park()) - continue; - list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) + if (sqt_spin) + timeout = jiffies + sqd->sq_thread_idle; + continue; + } + + prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE); + if (!io_sqd_events_pending(sqd) && !current->task_works) { + bool needs_sched = true; + + list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) { io_ring_set_wakeup_flag(ctx); - schedule(); - start_jiffies = jiffies; + + if ((ctx->flags & IORING_SETUP_IOPOLL) && + !list_empty_careful(&ctx->iopoll_list)) { + needs_sched = false; + break; + } + if (io_sqring_entries(ctx)) { + needs_sched = false; + break; + } + } + + if (needs_sched) { + mutex_unlock(&sqd->lock); + schedule(); + mutex_lock(&sqd->lock); + } list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) io_ring_clear_wakeup_flag(ctx); } + + finish_wait(&sqd->wait, &wait); + timeout = jiffies + sqd->sq_thread_idle; }

+ io_uring_cancel_generic(true, sqd); + sqd->thread = NULL; + list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) + io_ring_set_wakeup_flag(ctx); io_run_task_work(); - io_sq_thread_drop_mm(); - - if (cur_css) - io_sq_thread_unassociate_blkcg(); - if (old_cred) - revert_creds(old_cred); - - kthread_parkme(); + mutex_unlock(&sqd->lock);

- return 0; + complete(&sqd->exited); + do_exit(0); }

struct io_wait_queue { struct wait_queue_entry wq; struct io_ring_ctx *ctx; - unsigned to_wait; + unsigned cq_tail; unsigned nr_timeouts; };

static inline bool io_should_wake(struct io_wait_queue *iowq) { struct io_ring_ctx *ctx = iowq->ctx; + int dist = ctx->cached_cq_tail - (int) iowq->cq_tail;

/* * Wake up if we have enough events, or if a timeout occurred since we * started waiting. For timeouts, we always want to return to userspace, * regardless of event count. */ - return io_cqring_events(ctx) >= iowq->to_wait || - atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts; + return dist >= 0 || atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts; }

static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode, @@ -6975,7 +7408,7 @@ static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode, * Cannot safely flush overflowed CQEs from here, ensure we wake up * the task, and the next invocation will do it. */ - if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->cq_check_overflow)) + if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->check_cq_overflow)) return autoremove_wake_function(curr, mode, wake_flags, key); return -1; } @@ -6986,43 +7419,60 @@ static int io_run_task_work_sig(void) return 1; if (!signal_pending(current)) return 0; - if (current->jobctl & JOBCTL_TASK_WORK) { - spin_lock_irq(&current->sighand->siglock); - current->jobctl &= ~JOBCTL_TASK_WORK; - recalc_sigpending(); - spin_unlock_irq(&current->sighand->siglock); - return 1; - } + if (test_thread_flag(TIF_NOTIFY_SIGNAL)) + return -ERESTARTSYS; return -EINTR; }

+/* when returns >0, the caller should retry */ +static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx, + struct io_wait_queue *iowq, + ktime_t timeout) +{ + int ret; + + /* make sure we run task_work before checking for signals */ + ret = io_run_task_work_sig(); + if (ret || io_should_wake(iowq)) + return ret; + /* let the caller flush overflows, retry */ + if (test_bit(0, &ctx->check_cq_overflow)) + return 1; + + if (!schedule_hrtimeout(&timeout, HRTIMER_MODE_ABS)) + return -ETIME; + return 1; +} + /* * Wait until events become available, if we don't already have some. The * application must reap them itself, as they reside on the shared cq ring. */ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, - const sigset_t __user *sig, size_t sigsz) -{ - struct io_wait_queue iowq = { - .wq = { - .private = current, - .func = io_wake_function, - .entry = LIST_HEAD_INIT(iowq.wq.entry), - }, - .ctx = ctx, - .to_wait = min_events, - }; + const sigset_t __user *sig, size_t sigsz, + struct __kernel_timespec __user *uts) +{ + struct io_wait_queue iowq; struct io_rings *rings = ctx->rings; - int ret = 0; + ktime_t timeout = KTIME_MAX; + int ret;

do { - io_cqring_overflow_flush(ctx, false, NULL, NULL); + io_cqring_overflow_flush(ctx); if (io_cqring_events(ctx) >= min_events) return 0; if (!io_run_task_work()) break; } while (1);

+ if (uts) { + struct timespec64 ts; + + if (get_timespec64(&ts, uts)) + return -EFAULT; + timeout = ktime_add_ns(timespec64_to_ktime(ts), ktime_get_ns()); + } + if (sig) { #ifdef CONFIG_COMPAT if (in_compat_syscall()) @@ -7036,33 +7486,267 @@ static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events, return ret; }

+ init_waitqueue_func_entry(&iowq.wq, io_wake_function); + iowq.wq.private = current; + INIT_LIST_HEAD(&iowq.wq.entry); + iowq.ctx = ctx; iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts); + iowq.cq_tail = READ_ONCE(ctx->rings->cq.head) + min_events; + trace_io_uring_cqring_wait(ctx, min_events); do { - io_cqring_overflow_flush(ctx, false, NULL, NULL); - prepare_to_wait_exclusive(&ctx->wait, &iowq.wq, + /* if we can't even flush overflow, don't wait for more */ + if (!io_cqring_overflow_flush(ctx)) { + ret = -EBUSY; + break; + } + prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq, TASK_INTERRUPTIBLE); - /* make sure we run task_work before checking for signals */ - ret = io_run_task_work_sig(); - if (ret > 0) { - finish_wait(&ctx->wait, &iowq.wq); - continue; + ret = io_cqring_wait_schedule(ctx, &iowq, timeout); + finish_wait(&ctx->cq_wait, &iowq.wq); + cond_resched(); + } while (ret > 0); + + restore_saved_sigmask_unless(ret == -EINTR); + + return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0; +} + +static void io_free_page_table(void **table, size_t size) +{ + unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); + + for (i = 0; i < nr_tables; i++) + kfree(table[i]); + kfree(table); +} + +static void **io_alloc_page_table(size_t size) +{ + unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); + size_t init_size = size; + void **table; + + table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT); + if (!table) + return NULL; + + for (i = 0; i < nr_tables; i++) { + unsigned int this_size = min_t(size_t, size, PAGE_SIZE); + + table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT); + if (!table[i]) { + io_free_page_table(table, init_size); + return NULL; } - else if (ret < 0) + size -= this_size; + } + return table; +} + +static void io_rsrc_node_destroy(struct io_rsrc_node *ref_node) +{ + percpu_ref_exit(&ref_node->refs); + kfree(ref_node); +} + +static void io_rsrc_node_ref_zero(struct percpu_ref *ref) +{ + struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs); + struct io_ring_ctx *ctx = node->rsrc_data->ctx; + unsigned long flags; + bool first_add = false; + unsigned long delay = HZ; + + spin_lock_irqsave(&ctx->rsrc_ref_lock, flags); + node->done = true; + + /* if we are mid-quiesce then do not delay */ + if (node->rsrc_data->quiesce) + delay = 0; + + while (!list_empty(&ctx->rsrc_ref_list)) { + node = list_first_entry(&ctx->rsrc_ref_list, + struct io_rsrc_node, node); + /* recycle ref nodes in order */ + if (!node->done) + break; + list_del(&node->node); + first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist); + } + spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags); + + if (first_add) + mod_delayed_work(system_wq, &ctx->rsrc_put_work, delay); +} + +static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx) +{ + struct io_rsrc_node *ref_node; + + ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL); + if (!ref_node) + return NULL; + + if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero, + 0, GFP_KERNEL)) { + kfree(ref_node); + return NULL; + } + INIT_LIST_HEAD(&ref_node->node); + INIT_LIST_HEAD(&ref_node->rsrc_list); + ref_node->done = false; + return ref_node; +} + +static void io_rsrc_node_switch(struct io_ring_ctx *ctx, + struct io_rsrc_data *data_to_kill) +{ + WARN_ON_ONCE(!ctx->rsrc_backup_node); + WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node); + + if (data_to_kill) { + struct io_rsrc_node *rsrc_node = ctx->rsrc_node; + + rsrc_node->rsrc_data = data_to_kill; + spin_lock_irq(&ctx->rsrc_ref_lock); + list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list); + spin_unlock_irq(&ctx->rsrc_ref_lock); + + atomic_inc(&data_to_kill->refs); + percpu_ref_kill(&rsrc_node->refs); + ctx->rsrc_node = NULL; + } + + if (!ctx->rsrc_node) { + ctx->rsrc_node = ctx->rsrc_backup_node; + ctx->rsrc_backup_node = NULL; + } +} + +static int io_rsrc_node_switch_start(struct io_ring_ctx *ctx) +{ + if (ctx->rsrc_backup_node) + return 0; + ctx->rsrc_backup_node = io_rsrc_node_alloc(ctx); + return ctx->rsrc_backup_node ? 0 : -ENOMEM; +} + +static int io_rsrc_ref_quiesce(struct io_rsrc_data *data, struct io_ring_ctx *ctx) +{ + int ret; + + /* As we may drop ->uring_lock, other task may have started quiesce */ + if (data->quiesce) + return -ENXIO; + + data->quiesce = true; + do { + ret = io_rsrc_node_switch_start(ctx); + if (ret) break; - if (io_should_wake(&iowq)) + io_rsrc_node_switch(ctx, data); + + /* kill initial ref, already quiesced if zero */ + if (atomic_dec_and_test(&data->refs)) break; - if (test_bit(0, &ctx->cq_check_overflow)) { - finish_wait(&ctx->wait, &iowq.wq); - continue; + mutex_unlock(&ctx->uring_lock); + flush_delayed_work(&ctx->rsrc_put_work); + ret = wait_for_completion_interruptible(&data->done); + if (!ret) { + mutex_lock(&ctx->uring_lock); + if (atomic_read(&data->refs) > 0) { + /* + * it has been revived by another thread while + * we were unlocked + */ + mutex_unlock(&ctx->uring_lock); + } else { + break; + } + } + + atomic_inc(&data->refs); + /* wait for all works potentially completing data->done */ + flush_delayed_work(&ctx->rsrc_put_work); + reinit_completion(&data->done); + + ret = io_run_task_work_sig(); + mutex_lock(&ctx->uring_lock); + } while (ret >= 0); + data->quiesce = false; + + return ret; +} + +static u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx) +{ + unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK; + unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT; + + return &data->tags[table_idx][off]; +} + +static void io_rsrc_data_free(struct io_rsrc_data *data) +{ + size_t size = data->nr * sizeof(data->tags[0][0]); + + if (data->tags) + io_free_page_table((void **)data->tags, size); + kfree(data); +} + +static int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put, + u64 __user *utags, unsigned nr, + struct io_rsrc_data **pdata) +{ + struct io_rsrc_data *data; + int ret = -ENOMEM; + unsigned i; + + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0])); + if (!data->tags) { + kfree(data); + return -ENOMEM; + } + + data->nr = nr; + data->ctx = ctx; + data->do_put = do_put; + if (utags) { + ret = -EFAULT; + for (i = 0; i < nr; i++) { + u64 *tag_slot = io_get_tag_slot(data, i); + + if (copy_from_user(tag_slot, &utags[i], + sizeof(*tag_slot))) + goto fail; } - schedule(); - } while (1); - finish_wait(&ctx->wait, &iowq.wq); + }

- restore_saved_sigmask_unless(ret == -EINTR); + atomic_set(&data->refs, 1); + init_completion(&data->done); + *pdata = data; + return 0; +fail: + io_rsrc_data_free(data); + return ret; +}

- return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0; +static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files) +{ + table->files = kvcalloc(nr_files, sizeof(table->files[0]), + GFP_KERNEL_ACCOUNT); + return !!table->files; +} + +static void io_free_file_tables(struct io_file_table *table) +{ + kvfree(table->files); + table->files = NULL; }

static void __io_sqe_files_unregister(struct io_ring_ctx *ctx) @@ -7086,129 +7770,97 @@ static void __io_sqe_files_unregister(struct io_ring_ctx *ctx) fput(file); } #endif + io_free_file_tables(&ctx->file_table); + io_rsrc_data_free(ctx->file_data); + ctx->file_data = NULL; + ctx->nr_user_files = 0; }

-static void io_file_ref_kill(struct percpu_ref *ref) +static int io_sqe_files_unregister(struct io_ring_ctx *ctx) { - struct fixed_file_data *data; + unsigned nr = ctx->nr_user_files; + int ret;

- data = container_of(ref, struct fixed_file_data, refs); - complete(&data->done); -} + if (!ctx->file_data) + return -ENXIO;

-static void io_sqe_files_set_node(struct fixed_file_data *file_data, - struct fixed_file_ref_node *ref_node) -{ - spin_lock_bh(&file_data->lock); - file_data->node = ref_node; - list_add_tail(&ref_node->node, &file_data->ref_list); - spin_unlock_bh(&file_data->lock); - percpu_ref_get(&file_data->refs); + /* + * Quiesce may unlock ->uring_lock, and while it's not held + * prevent new requests using the table. + */ + ctx->nr_user_files = 0; + ret = io_rsrc_ref_quiesce(ctx->file_data, ctx); + ctx->nr_user_files = nr; + if (!ret) + __io_sqe_files_unregister(ctx); + return ret; }

- -static void io_sqe_files_kill_node(struct fixed_file_data *data) +static void io_sq_thread_unpark(struct io_sq_data *sqd) + __releases(&sqd->lock) { - struct fixed_file_ref_node *ref_node = NULL; + WARN_ON_ONCE(sqd->thread == current);

- spin_lock_bh(&data->lock); - ref_node = data->node; - spin_unlock_bh(&data->lock); - if (ref_node) - percpu_ref_kill(&ref_node->refs); + /* + * Do the dance but not conditional clear_bit() because it'd race with + * other threads incrementing park_pending and setting the bit. + */ + clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state); + if (atomic_dec_return(&sqd->park_pending)) + set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state); + mutex_unlock(&sqd->lock); }

-static int io_file_ref_quiesce(struct fixed_file_data *data, - struct io_ring_ctx *ctx) +static void io_sq_thread_park(struct io_sq_data *sqd) + __acquires(&sqd->lock) { - int ret; - struct fixed_file_ref_node *backup_node; - - if (data->quiesce) - return -ENXIO; - - data->quiesce = true; - do { - backup_node = alloc_fixed_file_ref_node(ctx); - if (!backup_node) - break; - - io_sqe_files_kill_node(data); - percpu_ref_kill(&data->refs); - flush_delayed_work(&ctx->file_put_work); - - ret = wait_for_completion_interruptible(&data->done); - if (!ret) - break; - - percpu_ref_resurrect(&data->refs); - io_sqe_files_set_node(data, backup_node); - backup_node = NULL; - reinit_completion(&data->done); - mutex_unlock(&ctx->uring_lock); - ret = io_run_task_work_sig(); - mutex_lock(&ctx->uring_lock); - - if (ret < 0) - break; - backup_node = alloc_fixed_file_ref_node(ctx); - ret = -ENOMEM; - if (!backup_node) - break; - } while (1); - data->quiesce = false; + WARN_ON_ONCE(sqd->thread == current);

- if (backup_node) - destroy_fixed_file_ref_node(backup_node); - return ret; + atomic_inc(&sqd->park_pending); + set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state); + mutex_lock(&sqd->lock); + if (sqd->thread) + wake_up_process(sqd->thread); }

-static int io_sqe_files_unregister(struct io_ring_ctx *ctx) +static void io_sq_thread_stop(struct io_sq_data *sqd) { - struct fixed_file_data *data = ctx->file_data; - unsigned nr_tables, i; - int ret; + WARN_ON_ONCE(sqd->thread == current); + WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state));

- /* - * percpu_ref_is_dying() is to stop parallel files unregister - * Since we possibly drop uring lock later in this function to - * run task work. - */ - if (!data || percpu_ref_is_dying(&data->refs)) - return -ENXIO; - ret = io_file_ref_quiesce(data, ctx); - if (ret) - return ret; - - __io_sqe_files_unregister(ctx); - nr_tables = DIV_ROUND_UP(ctx->nr_user_files, IORING_MAX_FILES_TABLE); - for (i = 0; i < nr_tables; i++) - kfree(data->table[i].files); - kfree(data->table); - percpu_ref_exit(&data->refs); - kfree(data); - ctx->file_data = NULL; - ctx->nr_user_files = 0; - return 0; + set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state); + mutex_lock(&sqd->lock); + if (sqd->thread) + wake_up_process(sqd->thread); + mutex_unlock(&sqd->lock); + wait_for_completion(&sqd->exited); }

static void io_put_sq_data(struct io_sq_data *sqd) { if (refcount_dec_and_test(&sqd->refs)) { - /* - * The park is a bit of a work-around, without it we get - * warning spews on shutdown with SQPOLL set and affinity - * set to a single CPU. - */ - if (sqd->thread) { - kthread_park(sqd->thread); - kthread_stop(sqd->thread); - } + WARN_ON_ONCE(atomic_read(&sqd->park_pending));

+ io_sq_thread_stop(sqd); kfree(sqd); } }

+static void io_sq_thread_finish(struct io_ring_ctx *ctx) +{ + struct io_sq_data *sqd = ctx->sq_data; + + if (sqd) { + io_sq_thread_park(sqd); + list_del_init(&ctx->sqd_list); + io_sqd_update_thread_idle(sqd); + io_sq_thread_unpark(sqd); + + io_put_sq_data(sqd); + ctx->sq_data = NULL; + } +} + static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p) { struct io_ring_ctx *ctx_attach; @@ -7229,92 +7881,46 @@ static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p) fdput(f); return ERR_PTR(-EINVAL); } + if (sqd->task_tgid != current->tgid) { + fdput(f); + return ERR_PTR(-EPERM); + }

refcount_inc(&sqd->refs); fdput(f); return sqd; }

-static struct io_sq_data *io_get_sq_data(struct io_uring_params *p) +static struct io_sq_data *io_get_sq_data(struct io_uring_params *p, + bool *attached) { struct io_sq_data *sqd;

- if (p->flags & IORING_SETUP_ATTACH_WQ) - return io_attach_sq_data(p); + *attached = false; + if (p->flags & IORING_SETUP_ATTACH_WQ) { + sqd = io_attach_sq_data(p); + if (!IS_ERR(sqd)) { + *attached = true; + return sqd; + } + /* fall through for EPERM case, setup new sqd/task */ + if (PTR_ERR(sqd) != -EPERM) + return sqd; + }

sqd = kzalloc(sizeof(*sqd), GFP_KERNEL); if (!sqd) return ERR_PTR(-ENOMEM);

+ atomic_set(&sqd->park_pending, 0); refcount_set(&sqd->refs, 1); INIT_LIST_HEAD(&sqd->ctx_list); - INIT_LIST_HEAD(&sqd->ctx_new_list); - mutex_init(&sqd->ctx_lock); mutex_init(&sqd->lock); init_waitqueue_head(&sqd->wait); + init_completion(&sqd->exited); return sqd; }

-static void io_sq_thread_unpark(struct io_sq_data *sqd) - __releases(&sqd->lock) -{ - if (!sqd->thread) - return; - kthread_unpark(sqd->thread); - mutex_unlock(&sqd->lock); -} - -static void io_sq_thread_park(struct io_sq_data *sqd) - __acquires(&sqd->lock) -{ - if (!sqd->thread) - return; - mutex_lock(&sqd->lock); - kthread_park(sqd->thread); -} - -static void io_sq_thread_stop(struct io_ring_ctx *ctx) -{ - struct io_sq_data *sqd = ctx->sq_data; - - if (sqd) { - if (sqd->thread) { - /* - * We may arrive here from the error branch in - * io_sq_offload_create() where the kthread is created - * without being waked up, thus wake it up now to make - * sure the wait will complete. - */ - wake_up_process(sqd->thread); - wait_for_completion(&ctx->sq_thread_comp); - - io_sq_thread_park(sqd); - } - - mutex_lock(&sqd->ctx_lock); - list_del(&ctx->sqd_list); - mutex_unlock(&sqd->ctx_lock); - - if (sqd->thread) { - finish_wait(&sqd->wait, &ctx->sqo_wait_entry); - io_sq_thread_unpark(sqd); - } - - io_put_sq_data(sqd); - ctx->sq_data = NULL; - } -} - -static void io_finish_async(struct io_ring_ctx *ctx) -{ - io_sq_thread_stop(ctx); - - if (ctx->io_wq) { - io_wq_destroy(ctx->io_wq); - ctx->io_wq = NULL; - } -} - #if defined(CONFIG_UNIX) /* * Ensure the UNIX gc is aware of our file set, so we are certain that @@ -7342,7 +7948,7 @@ static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset) skb->scm_io_uring = 1;

nr_files = 0; - fpl->user = get_uid(ctx->user); + fpl->user = get_uid(current_user()); for (i = 0; i < nr; i++) { struct file *file = io_file_from_index(ctx, i + offset);

@@ -7418,35 +8024,9 @@ static int io_sqe_files_scm(struct io_ring_ctx *ctx) } #endif

-static int io_sqe_alloc_file_tables(struct fixed_file_data *file_data, - unsigned nr_tables, unsigned nr_files) -{ - int i; - - for (i = 0; i < nr_tables; i++) { - struct fixed_file_table *table = &file_data->table[i]; - unsigned this_files; - - this_files = min(nr_files, IORING_MAX_FILES_TABLE); - table->files = kcalloc(this_files, sizeof(struct file *), - GFP_KERNEL_ACCOUNT); - if (!table->files) - break; - nr_files -= this_files; - } - - if (i == nr_tables) - return 0; - - for (i = 0; i < nr_tables; i++) { - struct fixed_file_table *table = &file_data->table[i]; - kfree(table->files); - } - return 1; -} - -static void io_ring_file_put(struct io_ring_ctx *ctx, struct file *file) +static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) { + struct file *file = prsrc->file; #if defined(CONFIG_UNIX) struct sock *sock = ctx->ring_sock->sk; struct sk_buff_head list, *head = &sock->sk_receive_queue; @@ -7507,117 +8087,61 @@ static void io_ring_file_put(struct io_ring_ctx *ctx, struct file *file) #endif }

-struct io_file_put { - struct list_head list; - struct file *file; -}; - -static void __io_file_put_work(struct fixed_file_ref_node *ref_node) +static void __io_rsrc_put_work(struct io_rsrc_node *ref_node) { - struct fixed_file_data *file_data = ref_node->file_data; - struct io_ring_ctx *ctx = file_data->ctx; - struct io_file_put *pfile, *tmp; + struct io_rsrc_data *rsrc_data = ref_node->rsrc_data; + struct io_ring_ctx *ctx = rsrc_data->ctx; + struct io_rsrc_put *prsrc, *tmp; + + list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) { + list_del(&prsrc->list); + + if (prsrc->tag) { + bool lock_ring = ctx->flags & IORING_SETUP_IOPOLL;

- list_for_each_entry_safe(pfile, tmp, &ref_node->file_list, list) { - list_del(&pfile->list); - io_ring_file_put(ctx, pfile->file); - kfree(pfile); + io_ring_submit_lock(ctx, lock_ring); + spin_lock(&ctx->completion_lock); + io_fill_cqe_aux(ctx, prsrc->tag, 0, 0); + io_commit_cqring(ctx); + spin_unlock(&ctx->completion_lock); + io_cqring_ev_posted(ctx); + io_ring_submit_unlock(ctx, lock_ring); + } + + rsrc_data->do_put(ctx, prsrc); + kfree(prsrc); }

- percpu_ref_exit(&ref_node->refs); - kfree(ref_node); - percpu_ref_put(&file_data->refs); + io_rsrc_node_destroy(ref_node); + if (atomic_dec_and_test(&rsrc_data->refs)) + complete(&rsrc_data->done); }

-static void io_file_put_work(struct work_struct *work) +static void io_rsrc_put_work(struct work_struct *work) { struct io_ring_ctx *ctx; struct llist_node *node;

- ctx = container_of(work, struct io_ring_ctx, file_put_work.work); - node = llist_del_all(&ctx->file_put_llist); + ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work); + node = llist_del_all(&ctx->rsrc_put_llist);

while (node) { - struct fixed_file_ref_node *ref_node; + struct io_rsrc_node *ref_node; struct llist_node *next = node->next;

- ref_node = llist_entry(node, struct fixed_file_ref_node, llist); - __io_file_put_work(ref_node); + ref_node = llist_entry(node, struct io_rsrc_node, llist); + __io_rsrc_put_work(ref_node); node = next; } }

-static void io_file_data_ref_zero(struct percpu_ref *ref) -{ - struct fixed_file_ref_node *ref_node; - struct fixed_file_data *data; - struct io_ring_ctx *ctx; - bool first_add = false; - int delay = HZ; - - ref_node = container_of(ref, struct fixed_file_ref_node, refs); - data = ref_node->file_data; - ctx = data->ctx; - - spin_lock_bh(&data->lock); - ref_node->done = true; - - while (!list_empty(&data->ref_list)) { - ref_node = list_first_entry(&data->ref_list, - struct fixed_file_ref_node, node); - /* recycle ref nodes in order */ - if (!ref_node->done) - break; - list_del(&ref_node->node); - first_add |= llist_add(&ref_node->llist, &ctx->file_put_llist); - } - spin_unlock_bh(&data->lock); - - if (percpu_ref_is_dying(&data->refs)) - delay = 0; - - if (!delay) - mod_delayed_work(system_wq, &ctx->file_put_work, 0); - else if (first_add) - queue_delayed_work(system_wq, &ctx->file_put_work, delay); -} - -static struct fixed_file_ref_node *alloc_fixed_file_ref_node( - struct io_ring_ctx *ctx) -{ - struct fixed_file_ref_node *ref_node; - - ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL); - if (!ref_node) - return NULL; - - if (percpu_ref_init(&ref_node->refs, io_file_data_ref_zero, - 0, GFP_KERNEL)) { - kfree(ref_node); - return NULL; - } - INIT_LIST_HEAD(&ref_node->node); - INIT_LIST_HEAD(&ref_node->file_list); - ref_node->file_data = ctx->file_data; - ref_node->done = false; - return ref_node; -} - -static void destroy_fixed_file_ref_node(struct fixed_file_ref_node *ref_node) -{ - percpu_ref_exit(&ref_node->refs); - kfree(ref_node); -} - static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, - unsigned nr_args) + unsigned nr_args, u64 __user *tags) { __s32 __user *fds = (__s32 __user *) arg; - unsigned nr_tables, i; struct file *file; - int fd, ret = -ENOMEM; - struct fixed_file_ref_node *ref_node; - struct fixed_file_data *file_data; + int fd, ret; + unsigned i;

if (ctx->file_data) return -EBUSY; @@ -7627,44 +8151,34 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, return -EMFILE; if (nr_args > rlimit(RLIMIT_NOFILE)) return -EMFILE; + ret = io_rsrc_node_switch_start(ctx); + if (ret) + return ret; + ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args, + &ctx->file_data); + if (ret) + return ret;

- file_data = kzalloc(sizeof(*ctx->file_data), GFP_KERNEL_ACCOUNT); - if (!file_data) - return -ENOMEM; - file_data->ctx = ctx; - init_completion(&file_data->done); - INIT_LIST_HEAD(&file_data->ref_list); - spin_lock_init(&file_data->lock); - - nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE); - file_data->table = kcalloc(nr_tables, sizeof(*file_data->table), - GFP_KERNEL_ACCOUNT); - if (!file_data->table) - goto out_free; - - if (percpu_ref_init(&file_data->refs, io_file_ref_kill, - PERCPU_REF_ALLOW_REINIT, GFP_KERNEL)) + ret = -ENOMEM; + if (!io_alloc_file_tables(&ctx->file_table, nr_args)) goto out_free;

- if (io_sqe_alloc_file_tables(file_data, nr_tables, nr_args)) - goto out_ref; - ctx->file_data = file_data; - for (i = 0; i < nr_args; i++, ctx->nr_user_files++) { - struct fixed_file_table *table; - unsigned index; - if (copy_from_user(&fd, &fds[i], sizeof(fd))) { ret = -EFAULT; goto out_fput; } /* allow sparse sets */ - if (fd == -1) + if (fd == -1) { + ret = -EINVAL; + if (unlikely(*io_get_tag_slot(ctx->file_data, i))) + goto out_fput; continue; + }

file = fget(fd); ret = -EBADF; - if (!file) + if (unlikely(!file)) goto out_fput;

/* @@ -7678,24 +8192,16 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, fput(file); goto out_fput; } - table = &file_data->table[i >> IORING_FILE_TABLE_SHIFT]; - index = i & IORING_FILE_TABLE_MASK; - table->files[index] = file; + io_fixed_file_set(io_fixed_file_slot(&ctx->file_table, i), file); }

ret = io_sqe_files_scm(ctx); if (ret) { - io_sqe_files_unregister(ctx); + __io_sqe_files_unregister(ctx); return ret; }

- ref_node = alloc_fixed_file_ref_node(ctx); - if (!ref_node) { - io_sqe_files_unregister(ctx); - return -ENOMEM; - } - - io_sqe_files_set_node(file_data, ref_node); + io_rsrc_node_switch(ctx, NULL); return ret; out_fput: for (i = 0; i < ctx->nr_user_files; i++) { @@ -7703,14 +8209,10 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, if (file) fput(file); } - for (i = 0; i < nr_tables; i++) - kfree(file_data->table[i].files); + io_free_file_tables(&ctx->file_table); ctx->nr_user_files = 0; -out_ref: - percpu_ref_exit(&file_data->refs); out_free: - kfree(file_data->table); - kfree(file_data); + io_rsrc_data_free(ctx->file_data); ctx->file_data = NULL; return ret; } @@ -7745,76 +8247,172 @@ static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file, skb = NULL; } } - spin_unlock_irq(&head->lock); + spin_unlock_irq(&head->lock); + + if (skb) { + fput(file); + return 0; + } + + return __io_sqe_files_scm(ctx, 1, index); +#else + return 0; +#endif +} + +static int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx, + struct io_rsrc_node *node, void *rsrc) +{ + u64 *tag_slot = io_get_tag_slot(data, idx); + struct io_rsrc_put *prsrc; + + prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL); + if (!prsrc) + return -ENOMEM; + + prsrc->tag = *tag_slot; + *tag_slot = 0; + prsrc->rsrc = rsrc; + list_add(&prsrc->list, &node->rsrc_list); + return 0; +} + +static int io_install_fixed_file(struct io_kiocb *req, struct file *file, + unsigned int issue_flags, u32 slot_index) +{ + struct io_ring_ctx *ctx = req->ctx; + bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK; + bool needs_switch = false; + struct io_fixed_file *file_slot; + int ret = -EBADF; + + io_ring_submit_lock(ctx, !force_nonblock); + if (file->f_op == &io_uring_fops) + goto err; + ret = -ENXIO; + if (!ctx->file_data) + goto err; + ret = -EINVAL; + if (slot_index >= ctx->nr_user_files) + goto err; + + slot_index = array_index_nospec(slot_index, ctx->nr_user_files); + file_slot = io_fixed_file_slot(&ctx->file_table, slot_index); + + if (file_slot->file_ptr) { + struct file *old_file; + + ret = io_rsrc_node_switch_start(ctx); + if (ret) + goto err; + + old_file = (struct file *)(file_slot->file_ptr & FFS_MASK); + ret = io_queue_rsrc_removal(ctx->file_data, slot_index, + ctx->rsrc_node, old_file); + if (ret) + goto err; + file_slot->file_ptr = 0; + needs_switch = true; + } + + *io_get_tag_slot(ctx->file_data, slot_index) = 0; + io_fixed_file_set(file_slot, file); + ret = io_sqe_file_register(ctx, file, slot_index); + if (ret) { + file_slot->file_ptr = 0; + goto err; + }

- if (skb) { + ret = 0; +err: + if (needs_switch) + io_rsrc_node_switch(ctx, ctx->file_data); + io_ring_submit_unlock(ctx, !force_nonblock); + if (ret) fput(file); - return 0; - } - - return __io_sqe_files_scm(ctx, 1, index); -#else - return 0; -#endif + return ret; }

-static int io_queue_file_removal(struct fixed_file_data *data, - struct file *file) +static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags) { - struct io_file_put *pfile; - struct fixed_file_ref_node *ref_node = data->node; + unsigned int offset = req->close.file_slot - 1; + struct io_ring_ctx *ctx = req->ctx; + struct io_fixed_file *file_slot; + struct file *file; + int ret;

- pfile = kzalloc(sizeof(*pfile), GFP_KERNEL); - if (!pfile) - return -ENOMEM; + io_ring_submit_lock(ctx, !(issue_flags & IO_URING_F_NONBLOCK)); + ret = -ENXIO; + if (unlikely(!ctx->file_data)) + goto out; + ret = -EINVAL; + if (offset >= ctx->nr_user_files) + goto out; + ret = io_rsrc_node_switch_start(ctx); + if (ret) + goto out; + + offset = array_index_nospec(offset, ctx->nr_user_files); + file_slot = io_fixed_file_slot(&ctx->file_table, offset); + ret = -EBADF; + if (!file_slot->file_ptr) + goto out;

- pfile->file = file; - list_add(&pfile->list, &ref_node->file_list); + file = (struct file *)(file_slot->file_ptr & FFS_MASK); + ret = io_queue_rsrc_removal(ctx->file_data, offset, ctx->rsrc_node, file); + if (ret) + goto out;

- return 0; + file_slot->file_ptr = 0; + io_rsrc_node_switch(ctx, ctx->file_data); + ret = 0; +out: + io_ring_submit_unlock(ctx, !(issue_flags & IO_URING_F_NONBLOCK)); + return ret; }

static int __io_sqe_files_update(struct io_ring_ctx *ctx, - struct io_uring_files_update *up, + struct io_uring_rsrc_update2 *up, unsigned nr_args) { - struct fixed_file_data *data = ctx->file_data; - struct fixed_file_ref_node *ref_node; + u64 __user *tags = u64_to_user_ptr(up->tags); + __s32 __user *fds = u64_to_user_ptr(up->data); + struct io_rsrc_data *data = ctx->file_data; + struct io_fixed_file *file_slot; struct file *file; - __s32 __user *fds; - int fd, i, err; - __u32 done; + int fd, i, err = 0; + unsigned int done; bool needs_switch = false;

- if (check_add_overflow(up->offset, nr_args, &done)) - return -EOVERFLOW; - if (done > ctx->nr_user_files) + if (!ctx->file_data) + return -ENXIO; + if (up->offset + nr_args > ctx->nr_user_files) return -EINVAL;

- ref_node = alloc_fixed_file_ref_node(ctx); - if (!ref_node) - return -ENOMEM; - - done = 0; - fds = u64_to_user_ptr(up->fds); - while (nr_args) { - struct fixed_file_table *table; - unsigned index; + for (done = 0; done < nr_args; done++) { + u64 tag = 0;

- err = 0; - if (copy_from_user(&fd, &fds[done], sizeof(fd))) { + if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) || + copy_from_user(&fd, &fds[done], sizeof(fd))) { err = -EFAULT; break; } - i = array_index_nospec(up->offset, ctx->nr_user_files); - table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT]; - index = i & IORING_FILE_TABLE_MASK; - if (table->files[index]) { - file = table->files[index]; - err = io_queue_file_removal(data, file); + if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) { + err = -EINVAL; + break; + } + if (fd == IORING_REGISTER_FILES_SKIP) + continue; + + i = array_index_nospec(up->offset + done, ctx->nr_user_files); + file_slot = io_fixed_file_slot(&ctx->file_table, i); + + if (file_slot->file_ptr) { + file = (struct file *)(file_slot->file_ptr & FFS_MASK); + err = io_queue_rsrc_removal(data, i, ctx->rsrc_node, file); if (err) break; - table->files[index] = NULL; + file_slot->file_ptr = 0; needs_switch = true; } if (fd != -1) { @@ -7836,106 +8434,61 @@ static int __io_sqe_files_update(struct io_ring_ctx *ctx, err = -EBADF; break; } - table->files[index] = file; + *io_get_tag_slot(data, i) = tag; + io_fixed_file_set(file_slot, file); err = io_sqe_file_register(ctx, file, i); if (err) { - table->files[index] = NULL; + file_slot->file_ptr = 0; fput(file); break; } } - nr_args--; - done++; - up->offset++; }

- if (needs_switch) { - percpu_ref_kill(&data->node->refs); - io_sqe_files_set_node(data, ref_node); - } else - destroy_fixed_file_ref_node(ref_node); - + if (needs_switch) + io_rsrc_node_switch(ctx, data); return done ? done : err; }

-static int io_sqe_files_update(struct io_ring_ctx *ctx, void __user *arg, - unsigned nr_args) -{ - struct io_uring_files_update up; - - if (!ctx->file_data) - return -ENXIO; - if (!nr_args) - return -EINVAL; - if (copy_from_user(&up, arg, sizeof(up))) - return -EFAULT; - if (up.resv) - return -EINVAL; - - return __io_sqe_files_update(ctx, &up, nr_args); -} - -static void io_free_work(struct io_wq_work *work) -{ - struct io_kiocb *req = container_of(work, struct io_kiocb, work); - - /* Consider that io_steal_work() relies on this ref */ - io_put_req(req); -} - -static int io_init_wq_offload(struct io_ring_ctx *ctx, - struct io_uring_params *p) +static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx, + struct task_struct *task) { + struct io_wq_hash *hash; struct io_wq_data data; - struct fd f; - struct io_ring_ctx *ctx_attach; unsigned int concurrency; - int ret = 0; - - data.user = ctx->user; - data.free_work = io_free_work; - data.do_work = io_wq_submit_work;

- if (!(p->flags & IORING_SETUP_ATTACH_WQ)) { - /* Do QD, or 4 * CPUS, whatever is smallest */ - concurrency = min(ctx->sq_entries, 4 * num_online_cpus()); - - ctx->io_wq = io_wq_create(concurrency, &data); - if (IS_ERR(ctx->io_wq)) { - ret = PTR_ERR(ctx->io_wq); - ctx->io_wq = NULL; + mutex_lock(&ctx->uring_lock); + hash = ctx->hash_map; + if (!hash) { + hash = kzalloc(sizeof(*hash), GFP_KERNEL); + if (!hash) { + mutex_unlock(&ctx->uring_lock); + return ERR_PTR(-ENOMEM); } - return ret; + refcount_set(&hash->refs, 1); + init_waitqueue_head(&hash->wait); + ctx->hash_map = hash; } + mutex_unlock(&ctx->uring_lock);

- f = fdget(p->wq_fd); - if (!f.file) - return -EBADF; - - if (f.file->f_op != &io_uring_fops) { - ret = -EINVAL; - goto out_fput; - } + data.hash = hash; + data.task = task; + data.free_work = io_wq_free_work; + data.do_work = io_wq_submit_work;

- ctx_attach = f.file->private_data; - /* @io_wq is protected by holding the fd */ - if (!io_wq_get(ctx_attach->io_wq, &data)) { - ret = -EINVAL; - goto out_fput; - } + /* Do QD, or 4 * CPUS, whatever is smallest */ + concurrency = min(ctx->sq_entries, 4 * num_online_cpus());

- ctx->io_wq = ctx_attach->io_wq; -out_fput: - fdput(f); - return ret; + return io_wq_create(concurrency, &data); }

-static int io_uring_alloc_task_context(struct task_struct *task) +static int io_uring_alloc_task_context(struct task_struct *task, + struct io_ring_ctx *ctx) { struct io_uring_task *tctx; int ret;

- tctx = kmalloc(sizeof(*tctx), GFP_KERNEL); + tctx = kzalloc(sizeof(*tctx), GFP_KERNEL); if (unlikely(!tctx)) return -ENOMEM;

@@ -7945,14 +8498,22 @@ static int io_uring_alloc_task_context(struct task_struct *task) return ret; }

+ tctx->io_wq = io_init_wq_offload(ctx, task); + if (IS_ERR(tctx->io_wq)) { + ret = PTR_ERR(tctx->io_wq); + percpu_counter_destroy(&tctx->inflight); + kfree(tctx); + return ret; + } + xa_init(&tctx->xa); init_waitqueue_head(&tctx->wait); - tctx->last = NULL; atomic_set(&tctx->in_idle, 0); - tctx->sqpoll = false; - io_init_identity(&tctx->__identity); - tctx->identity = &tctx->__identity; + atomic_set(&tctx->inflight_tracked, 0); task->io_uring = tctx; + spin_lock_init(&tctx->task_lock); + INIT_WQ_LIST(&tctx->task_list); + init_task_work(&tctx->task_work, tctx_task_work); return 0; }

@@ -7961,9 +8522,9 @@ void __io_uring_free(struct task_struct *tsk) struct io_uring_task *tctx = tsk->io_uring;

WARN_ON_ONCE(!xa_empty(&tctx->xa)); - WARN_ON_ONCE(refcount_read(&tctx->identity->count) != 1); - if (tctx->identity != &tctx->__identity) - kfree(tctx->identity); + WARN_ON_ONCE(tctx->io_wq); + WARN_ON_ONCE(tctx->cached_refs); + percpu_counter_destroy(&tctx->inflight); kfree(tctx); tsk->io_uring = NULL; @@ -7974,54 +8535,71 @@ static int io_sq_offload_create(struct io_ring_ctx *ctx, { int ret;

+ /* Retain compatibility with failing for an invalid attach attempt */ + if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) == + IORING_SETUP_ATTACH_WQ) { + struct fd f; + + f = fdget(p->wq_fd); + if (!f.file) + return -ENXIO; + if (f.file->f_op != &io_uring_fops) { + fdput(f); + return -EINVAL; + } + fdput(f); + } if (ctx->flags & IORING_SETUP_SQPOLL) { + struct task_struct *tsk; struct io_sq_data *sqd; + bool attached;

- ret = -EPERM; - if (!capable(CAP_SYS_ADMIN)) - goto err; - - sqd = io_get_sq_data(p); + sqd = io_get_sq_data(p, &attached); if (IS_ERR(sqd)) { ret = PTR_ERR(sqd); goto err; }

+ ctx->sq_creds = get_current_cred(); ctx->sq_data = sqd; - io_sq_thread_park(sqd); - mutex_lock(&sqd->ctx_lock); - list_add(&ctx->sqd_list, &sqd->ctx_new_list); - mutex_unlock(&sqd->ctx_lock); - io_sq_thread_unpark(sqd); - ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle); if (!ctx->sq_thread_idle) ctx->sq_thread_idle = HZ;

- if (sqd->thread) - goto done; + io_sq_thread_park(sqd); + list_add(&ctx->sqd_list, &sqd->ctx_list); + io_sqd_update_thread_idle(sqd); + /* don't attach to a dying SQPOLL thread, would be racy */ + ret = (attached && !sqd->thread) ? -ENXIO : 0; + io_sq_thread_unpark(sqd); + + if (ret < 0) + goto err; + if (attached) + return 0;

if (p->flags & IORING_SETUP_SQ_AFF) { int cpu = p->sq_thread_cpu;

ret = -EINVAL; - if (cpu >= nr_cpu_ids) - goto err; - if (!cpu_online(cpu)) - goto err; - - sqd->thread = kthread_create_on_cpu(io_sq_thread, sqd, - cpu, "io_uring-sq"); + if (cpu >= nr_cpu_ids || !cpu_online(cpu)) + goto err_sqpoll; + sqd->sq_cpu = cpu; } else { - sqd->thread = kthread_create(io_sq_thread, sqd, - "io_uring-sq"); + sqd->sq_cpu = -1; } - if (IS_ERR(sqd->thread)) { - ret = PTR_ERR(sqd->thread); - sqd->thread = NULL; - goto err; + + sqd->task_pid = current->pid; + sqd->task_tgid = current->tgid; + tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE); + if (IS_ERR(tsk)) { + ret = PTR_ERR(tsk); + goto err_sqpoll; } - ret = io_uring_alloc_task_context(sqd->thread); + + sqd->thread = tsk; + ret = io_uring_alloc_task_context(tsk, ctx); + wake_up_new_task(tsk); if (ret) goto err; } else if (p->flags & IORING_SETUP_SQ_AFF) { @@ -8030,26 +8608,14 @@ static int io_sq_offload_create(struct io_ring_ctx *ctx, goto err; }

-done: - ret = io_init_wq_offload(ctx, p); - if (ret) - goto err; - return 0; +err_sqpoll: + complete(&ctx->sq_data->exited); err: - io_finish_async(ctx); + io_sq_thread_finish(ctx); return ret; }

-static void io_sq_offload_start(struct io_ring_ctx *ctx) -{ - struct io_sq_data *sqd = ctx->sq_data; - - ctx->flags &= ~IORING_SETUP_R_DISABLED; - if ((ctx->flags & IORING_SETUP_SQPOLL) && sqd && sqd->thread) - wake_up_process(sqd->thread); -} - static inline void __io_unaccount_mem(struct user_struct *user, unsigned long nr_pages) { @@ -8075,37 +8641,27 @@ static inline int __io_account_mem(struct user_struct *user, return 0; }

-static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages, - enum io_mem_account acct) +static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) { - if (ctx->limit_mem) + if (ctx->user) __io_unaccount_mem(ctx->user, nr_pages);

- if (ctx->mm_account) { - if (acct == ACCT_LOCKED) - ctx->mm_account->locked_vm -= nr_pages; - else if (acct == ACCT_PINNED) - atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm); - } + if (ctx->mm_account) + atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm); }

-static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages, - enum io_mem_account acct) +static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages) { int ret;

- if (ctx->limit_mem) { + if (ctx->user) { ret = __io_account_mem(ctx->user, nr_pages); if (ret) return ret; }

- if (ctx->mm_account) { - if (acct == ACCT_LOCKED) - ctx->mm_account->locked_vm += nr_pages; - else if (acct == ACCT_PINNED) - atomic64_add(nr_pages, &ctx->mm_account->pinned_vm); - } + if (ctx->mm_account) + atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);

return 0; } @@ -8124,10 +8680,9 @@ static void io_mem_free(void *ptr)

static void *io_mem_alloc(size_t size) { - gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP | - __GFP_NORETRY; + gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP;

- return (void *) __get_free_pages(gfp_flags, get_order(size)); + return (void *) __get_free_pages(gfp, get_order(size)); }

static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries, @@ -8159,41 +8714,58 @@ static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries, return off; }

-static unsigned long ring_pages(unsigned sq_entries, unsigned cq_entries) +static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot) { - size_t pages; - - pages = (size_t)1 << get_order( - rings_size(sq_entries, cq_entries, NULL)); - pages += (size_t)1 << get_order( - array_size(sizeof(struct io_uring_sqe), sq_entries)); + struct io_mapped_ubuf *imu = *slot; + unsigned int i;

- return pages; + if (imu != ctx->dummy_ubuf) { + for (i = 0; i < imu->nr_bvecs; i++) + unpin_user_page(imu->bvec[i].bv_page); + if (imu->acct_pages) + io_unaccount_mem(ctx, imu->acct_pages); + kvfree(imu); + } + *slot = NULL; }

-static int io_sqe_buffer_unregister(struct io_ring_ctx *ctx) +static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc) { - int i, j; + io_buffer_unmap(ctx, &prsrc->buf); + prsrc->buf = NULL; +}

- if (!ctx->user_bufs) - return -ENXIO; +static void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx) +{ + unsigned int i;

- for (i = 0; i < ctx->nr_user_bufs; i++) { - struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; + for (i = 0; i < ctx->nr_user_bufs; i++) + io_buffer_unmap(ctx, &ctx->user_bufs[i]); + kfree(ctx->user_bufs); + io_rsrc_data_free(ctx->buf_data); + ctx->user_bufs = NULL; + ctx->buf_data = NULL; + ctx->nr_user_bufs = 0; +}

- for (j = 0; j < imu->nr_bvecs; j++) - unpin_user_page(imu->bvec[j].bv_page); +static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx) +{ + unsigned nr = ctx->nr_user_bufs; + int ret;

- if (imu->acct_pages) - io_unaccount_mem(ctx, imu->acct_pages, ACCT_PINNED); - kvfree(imu->bvec); - imu->nr_bvecs = 0; - } + if (!ctx->buf_data) + return -ENXIO;

- kfree(ctx->user_bufs); - ctx->user_bufs = NULL; + /* + * Quiesce may unlock ->uring_lock, and while it's not held + * prevent new requests using the table. + */ ctx->nr_user_bufs = 0; - return 0; + ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx); + ctx->nr_user_bufs = nr; + if (!ret) + __io_sqe_buffers_unregister(ctx); + return ret; }

static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst, @@ -8245,7 +8817,7 @@ static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,

/* check previously registered pages */ for (i = 0; i < ctx->nr_user_bufs; i++) { - struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; + struct io_mapped_ubuf *imu = ctx->user_bufs[i];

for (j = 0; j < imu->nr_bvecs; j++) { if (!PageCompound(imu->bvec[j].bv_page)) @@ -8264,6 +8836,7 @@ static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages, { int i, ret;

+ imu->acct_pages = 0; for (i = 0; i < nr_pages; i++) { if (!PageCompound(pages[i])) { imu->acct_pages++; @@ -8283,147 +8856,252 @@ static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages, if (!imu->acct_pages) return 0;

- ret = io_account_mem(ctx, imu->acct_pages, ACCT_PINNED); + ret = io_account_mem(ctx, imu->acct_pages); if (ret) imu->acct_pages = 0; return ret; }

-static int io_sqe_buffer_register(struct io_ring_ctx *ctx, void __user *arg, - unsigned nr_args) +static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov, + struct io_mapped_ubuf **pimu, + struct page **last_hpage) { + struct io_mapped_ubuf *imu = NULL; struct vm_area_struct **vmas = NULL; struct page **pages = NULL; + unsigned long off, start, end, ubuf; + size_t size; + int ret, pret, nr_pages, i; + + if (!iov->iov_base) { + *pimu = ctx->dummy_ubuf; + return 0; + } + + ubuf = (unsigned long) iov->iov_base; + end = (ubuf + iov->iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT; + start = ubuf >> PAGE_SHIFT; + nr_pages = end - start; + + *pimu = NULL; + ret = -ENOMEM; + + pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL); + if (!pages) + goto done; + + vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *), + GFP_KERNEL); + if (!vmas) + goto done; + + imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL); + if (!imu) + goto done; + + ret = 0; + mmap_read_lock(current->mm); + pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM, + pages, vmas); + if (pret == nr_pages) { + /* don't support file backed memory */ + for (i = 0; i < nr_pages; i++) { + struct vm_area_struct *vma = vmas[i]; + + if (vma_is_shmem(vma)) + continue; + if (vma->vm_file && + !is_file_hugepages(vma->vm_file)) { + ret = -EOPNOTSUPP; + break; + } + } + } else { + ret = pret < 0 ? pret : -EFAULT; + } + mmap_read_unlock(current->mm); + if (ret) { + /* + * if we did partial map, or found file backed vmas, + * release any pages we did get + */ + if (pret > 0) + unpin_user_pages(pages, pret); + goto done; + } + + ret = io_buffer_account_pin(ctx, pages, pret, imu, last_hpage); + if (ret) { + unpin_user_pages(pages, pret); + goto done; + } + + off = ubuf & ~PAGE_MASK; + size = iov->iov_len; + for (i = 0; i < nr_pages; i++) { + size_t vec_len; + + vec_len = min_t(size_t, size, PAGE_SIZE - off); + imu->bvec[i].bv_page = pages[i]; + imu->bvec[i].bv_len = vec_len; + imu->bvec[i].bv_offset = off; + off = 0; + size -= vec_len; + } + /* store original address for later verification */ + imu->ubuf = ubuf; + imu->ubuf_end = ubuf + iov->iov_len; + imu->nr_bvecs = nr_pages; + *pimu = imu; + ret = 0; +done: + if (ret) + kvfree(imu); + kvfree(pages); + kvfree(vmas); + return ret; +} + +static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args) +{ + ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL); + return ctx->user_bufs ? 0 : -ENOMEM; +} + +static int io_buffer_validate(struct iovec *iov) +{ + unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1); + + /* + * Don't impose further limits on the size and buffer + * constraints here, we'll -EINVAL later when IO is + * submitted if they are wrong. + */ + if (!iov->iov_base) + return iov->iov_len ? -EFAULT : 0; + if (!iov->iov_len) + return -EFAULT; + + /* arbitrary limit, but we need something */ + if (iov->iov_len > SZ_1G) + return -EFAULT; + + if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp)) + return -EOVERFLOW; + + return 0; +} + +static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg, + unsigned int nr_args, u64 __user *tags) +{ struct page *last_hpage = NULL; - int i, j, got_pages = 0; - int ret = -EINVAL; + struct io_rsrc_data *data; + int i, ret; + struct iovec iov;

if (ctx->user_bufs) return -EBUSY; - if (!nr_args || nr_args > UIO_MAXIOV) + if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS) return -EINVAL; + ret = io_rsrc_node_switch_start(ctx); + if (ret) + return ret; + ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data); + if (ret) + return ret; + ret = io_buffers_map_alloc(ctx, nr_args); + if (ret) { + io_rsrc_data_free(data); + return ret; + }

- ctx->user_bufs = kcalloc(nr_args, sizeof(struct io_mapped_ubuf), - GFP_KERNEL); - if (!ctx->user_bufs) - return -ENOMEM; - - for (i = 0; i < nr_args; i++) { - struct io_mapped_ubuf *imu = &ctx->user_bufs[i]; - unsigned long off, start, end, ubuf; - int pret, nr_pages; - struct iovec iov; - size_t size; - + for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) { ret = io_copy_iov(ctx, &iov, arg, i); if (ret) - goto err; + break; + ret = io_buffer_validate(&iov); + if (ret) + break; + if (!iov.iov_base && *io_get_tag_slot(data, i)) { + ret = -EINVAL; + break; + }

- /* - * Don't impose further limits on the size and buffer - * constraints here, we'll -EINVAL later when IO is - * submitted if they are wrong. - */ - ret = -EFAULT; - if (!iov.iov_base || !iov.iov_len) - goto err; + ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i], + &last_hpage); + if (ret) + break; + }

- /* arbitrary limit, but we need something */ - if (iov.iov_len > SZ_1G) - goto err; + WARN_ON_ONCE(ctx->buf_data);

- ubuf = (unsigned long) iov.iov_base; - end = (ubuf + iov.iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT; - start = ubuf >> PAGE_SHIFT; - nr_pages = end - start; + ctx->buf_data = data; + if (ret) + __io_sqe_buffers_unregister(ctx); + else + io_rsrc_node_switch(ctx, NULL); + return ret; +}

- ret = 0; - if (!pages || nr_pages > got_pages) { - kvfree(vmas); - kvfree(pages); - pages = kvmalloc_array(nr_pages, sizeof(struct page *), - GFP_KERNEL); - vmas = kvmalloc_array(nr_pages, - sizeof(struct vm_area_struct *), - GFP_KERNEL); - if (!pages || !vmas) { - ret = -ENOMEM; - goto err; - } - got_pages = nr_pages; - } +static int __io_sqe_buffers_update(struct io_ring_ctx *ctx, + struct io_uring_rsrc_update2 *up, + unsigned int nr_args) +{ + u64 __user *tags = u64_to_user_ptr(up->tags); + struct iovec iov, __user *iovs = u64_to_user_ptr(up->data); + struct page *last_hpage = NULL; + bool needs_switch = false; + __u32 done; + int i, err; + + if (!ctx->buf_data) + return -ENXIO; + if (up->offset + nr_args > ctx->nr_user_bufs) + return -EINVAL;

- imu->bvec = kvmalloc_array(nr_pages, sizeof(struct bio_vec), - GFP_KERNEL); - ret = -ENOMEM; - if (!imu->bvec) - goto err; + for (done = 0; done < nr_args; done++) { + struct io_mapped_ubuf *imu; + int offset = up->offset + done; + u64 tag = 0;

- ret = 0; - mmap_read_lock(current->mm); - pret = pin_user_pages(ubuf, nr_pages, - FOLL_WRITE | FOLL_LONGTERM, - pages, vmas); - if (pret == nr_pages) { - /* don't support file backed memory */ - for (j = 0; j < nr_pages; j++) { - struct vm_area_struct *vma = vmas[j]; - - if (vma->vm_file && - !is_file_hugepages(vma->vm_file)) { - ret = -EOPNOTSUPP; - break; - } - } - } else { - ret = pret < 0 ? pret : -EFAULT; - } - mmap_read_unlock(current->mm); - if (ret) { - /* - * if we did partial map, or found file backed vmas, - * release any pages we did get - */ - if (pret > 0) - unpin_user_pages(pages, pret); - kvfree(imu->bvec); - goto err; + err = io_copy_iov(ctx, &iov, iovs, done); + if (err) + break; + if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) { + err = -EFAULT; + break; } - - ret = io_buffer_account_pin(ctx, pages, pret, imu, &last_hpage); - if (ret) { - unpin_user_pages(pages, pret); - kvfree(imu->bvec); - goto err; + err = io_buffer_validate(&iov); + if (err) + break; + if (!iov.iov_base && tag) { + err = -EINVAL; + break; } + err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage); + if (err) + break;

- off = ubuf & ~PAGE_MASK; - size = iov.iov_len; - for (j = 0; j < nr_pages; j++) { - size_t vec_len; - - vec_len = min_t(size_t, size, PAGE_SIZE - off); - imu->bvec[j].bv_page = pages[j]; - imu->bvec[j].bv_len = vec_len; - imu->bvec[j].bv_offset = off; - off = 0; - size -= vec_len; + i = array_index_nospec(offset, ctx->nr_user_bufs); + if (ctx->user_bufs[i] != ctx->dummy_ubuf) { + err = io_queue_rsrc_removal(ctx->buf_data, i, + ctx->rsrc_node, ctx->user_bufs[i]); + if (unlikely(err)) { + io_buffer_unmap(ctx, &imu); + break; + } + ctx->user_bufs[i] = NULL; + needs_switch = true; } - /* store original address for later verification */ - imu->ubuf = ubuf; - imu->len = iov.iov_len; - imu->nr_bvecs = nr_pages;

- ctx->nr_user_bufs++; + ctx->user_bufs[i] = imu; + *io_get_tag_slot(ctx->buf_data, offset) = tag; } - kvfree(pages); - kvfree(vmas); - return 0; -err: - kvfree(pages); - kvfree(vmas); - io_sqe_buffer_unregister(ctx); - return ret; + + if (needs_switch) + io_rsrc_node_switch(ctx, ctx->buf_data); + return done ? done : err; }

static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg) @@ -8440,6 +9118,7 @@ static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg) ctx->cq_ev_fd = eventfd_ctx_fdget(fd); if (IS_ERR(ctx->cq_ev_fd)) { int ret = PTR_ERR(ctx->cq_ev_fd); + ctx->cq_ev_fd = NULL; return ret; } @@ -8467,26 +9146,68 @@ static void io_destroy_buffers(struct io_ring_ctx *ctx) __io_remove_buffers(ctx, buf, index, -1U); }

-static void io_ring_ctx_free(struct io_ring_ctx *ctx) +static void io_req_cache_free(struct list_head *list) { - io_finish_async(ctx); - io_sqe_buffer_unregister(ctx); + struct io_kiocb *req, *nxt;

- if (ctx->sqo_task) { - put_task_struct(ctx->sqo_task); - ctx->sqo_task = NULL; + list_for_each_entry_safe(req, nxt, list, inflight_entry) { + list_del(&req->inflight_entry); + kmem_cache_free(req_cachep, req); } +}

-#ifdef CONFIG_BLK_CGROUP - if (ctx->sqo_blkcg_css) - css_put(ctx->sqo_blkcg_css); -#endif +static void io_req_caches_free(struct io_ring_ctx *ctx) +{ + struct io_submit_state *state = &ctx->submit_state; + + mutex_lock(&ctx->uring_lock); + + if (state->free_reqs) { + kmem_cache_free_bulk(req_cachep, state->free_reqs, state->reqs); + state->free_reqs = 0; + } + + io_flush_cached_locked_reqs(ctx, state); + io_req_cache_free(&state->free_list); + mutex_unlock(&ctx->uring_lock); +} + +static void io_wait_rsrc_data(struct io_rsrc_data *data) +{ + if (data && !atomic_dec_and_test(&data->refs)) + wait_for_completion(&data->done); +} + +static void io_ring_ctx_free(struct io_ring_ctx *ctx) +{ + io_sq_thread_finish(ctx); + + /* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */ + io_wait_rsrc_data(ctx->buf_data); + io_wait_rsrc_data(ctx->file_data);

mutex_lock(&ctx->uring_lock); - io_sqe_files_unregister(ctx); + if (ctx->buf_data) + __io_sqe_buffers_unregister(ctx); + if (ctx->file_data) + __io_sqe_files_unregister(ctx); + if (ctx->rings) + __io_cqring_overflow_flush(ctx, true); mutex_unlock(&ctx->uring_lock); io_eventfd_unregister(ctx); io_destroy_buffers(ctx); + if (ctx->sq_creds) + put_cred(ctx->sq_creds); + + /* there are no registered resources left, nobody uses it */ + if (ctx->rsrc_node) + io_rsrc_node_destroy(ctx->rsrc_node); + if (ctx->rsrc_backup_node) + io_rsrc_node_destroy(ctx->rsrc_backup_node); + flush_delayed_work(&ctx->rsrc_put_work); + + WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list)); + WARN_ON_ONCE(!llist_empty(&ctx->rsrc_put_llist));

#if defined(CONFIG_UNIX) if (ctx->ring_sock) { @@ -8494,6 +9215,7 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx) sock_release(ctx->ring_sock); } #endif + WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list));

if (ctx->mm_account) { mmdrop(ctx->mm_account); @@ -8505,9 +9227,11 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx)

percpu_ref_exit(&ctx->refs); free_uid(ctx->user); - put_cred(ctx->creds); + io_req_caches_free(ctx); + if (ctx->hash_map) + io_wq_put_hash(ctx->hash_map); kfree(ctx->cancel_hash); - kmem_cache_free(req_cachep, ctx->fallback_req); + kfree(ctx->dummy_ubuf); kfree(ctx); }

@@ -8516,7 +9240,7 @@ static __poll_t io_uring_poll(struct file *file, poll_table *wait) struct io_ring_ctx *ctx = file->private_data; __poll_t mask = 0;

- poll_wait(file, &ctx->cq_wait, wait); + poll_wait(file, &ctx->poll_wait, wait); /* * synchronizes with barrier from wq_has_sleeper call in * io_commit_cqring @@ -8538,38 +9262,63 @@ static __poll_t io_uring_poll(struct file *file, poll_table *wait) * Users may get EPOLLIN meanwhile seeing nothing in cqring, this * pushs them to do the flush. */ - if (io_cqring_events(ctx) || test_bit(0, &ctx->cq_check_overflow)) + if (io_cqring_events(ctx) || test_bit(0, &ctx->check_cq_overflow)) mask |= EPOLLIN | EPOLLRDNORM;

return mask; }

-static int io_uring_fasync(int fd, struct file *file, int on) -{ - struct io_ring_ctx *ctx = file->private_data; - - return fasync_helper(fd, file, on, &ctx->cq_fasync); -} - static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id) { - struct io_identity *iod; + const struct cred *creds;

- iod = xa_erase(&ctx->personalities, id); - if (iod) { - put_cred(iod->creds); - if (refcount_dec_and_test(&iod->count)) - kfree(iod); + creds = xa_erase(&ctx->personalities, id); + if (creds) { + put_cred(creds); return 0; }

return -EINVAL; }

+struct io_tctx_exit { + struct callback_head task_work; + struct completion completion; + struct io_ring_ctx *ctx; +}; + +static void io_tctx_exit_cb(struct callback_head *cb) +{ + struct io_uring_task *tctx = current->io_uring; + struct io_tctx_exit *work; + + work = container_of(cb, struct io_tctx_exit, task_work); + /* + * When @in_idle, we're in cancellation and it's racy to remove the + * node. It'll be removed by the end of cancellation, just ignore it. + * tctx can be NULL if the queueing of this task_work raced with + * work cancelation off the exec path. + */ + if (tctx && !atomic_read(&tctx->in_idle)) + io_uring_del_tctx_node((unsigned long)work->ctx); + complete(&work->completion); +} + +static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data) +{ + struct io_kiocb *req = container_of(work, struct io_kiocb, work); + + return req->ctx == data; +} + static void io_ring_exit_work(struct work_struct *work) { - struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, - exit_work); + struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work); + unsigned long timeout = jiffies + HZ * 60 * 5; + unsigned long interval = HZ / 20; + struct io_tctx_exit exit; + struct io_tctx_node *node; + int ret;

/* * If we're doing polled IO and end up having requests being @@ -8578,53 +9327,100 @@ static void io_ring_exit_work(struct work_struct *work) * as nobody else will be looking for them. */ do { - io_iopoll_try_reap_events(ctx); - } while (!wait_for_completion_timeout(&ctx->ref_comp, HZ/20)); + io_uring_try_cancel_requests(ctx, NULL, true); + if (ctx->sq_data) { + struct io_sq_data *sqd = ctx->sq_data; + struct task_struct *tsk; + + io_sq_thread_park(sqd); + tsk = sqd->thread; + if (tsk && tsk->io_uring && tsk->io_uring->io_wq) + io_wq_cancel_cb(tsk->io_uring->io_wq, + io_cancel_ctx_cb, ctx, true); + io_sq_thread_unpark(sqd); + } + + if (WARN_ON_ONCE(time_after(jiffies, timeout))) { + /* there is little hope left, don't run it too often */ + interval = HZ * 60; + } + } while (!wait_for_completion_timeout(&ctx->ref_comp, interval)); + + init_completion(&exit.completion); + init_task_work(&exit.task_work, io_tctx_exit_cb); + exit.ctx = ctx; + /* + * Some may use context even when all refs and requests have been put, + * and they are free to do so while still holding uring_lock or + * completion_lock, see io_req_task_submit(). Apart from other work, + * this lock/unlock section also waits them to finish. + */ + mutex_lock(&ctx->uring_lock); + while (!list_empty(&ctx->tctx_list)) { + WARN_ON_ONCE(time_after(jiffies, timeout)); + + node = list_first_entry(&ctx->tctx_list, struct io_tctx_node, + ctx_node); + /* don't spin on a single task if cancellation failed */ + list_rotate_left(&ctx->tctx_list); + ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL); + if (WARN_ON_ONCE(ret)) + continue; + wake_up_process(node->task); + + mutex_unlock(&ctx->uring_lock); + wait_for_completion(&exit.completion); + mutex_lock(&ctx->uring_lock); + } + mutex_unlock(&ctx->uring_lock); + spin_lock(&ctx->completion_lock); + spin_unlock(&ctx->completion_lock); + io_ring_ctx_free(ctx); }

-static bool io_cancel_ctx_cb(struct io_wq_work *work, void *data) +/* Returns true if we found and killed one or more timeouts */ +static bool io_kill_timeouts(struct io_ring_ctx *ctx, struct task_struct *tsk, + bool cancel_all) { - struct io_kiocb *req = container_of(work, struct io_kiocb, work); + struct io_kiocb *req, *tmp; + int canceled = 0;

- return req->ctx == data; + spin_lock(&ctx->completion_lock); + spin_lock_irq(&ctx->timeout_lock); + list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) { + if (io_match_task(req, tsk, cancel_all)) { + io_kill_timeout(req, -ECANCELED); + canceled++; + } + } + spin_unlock_irq(&ctx->timeout_lock); + if (canceled != 0) + io_commit_cqring(ctx); + spin_unlock(&ctx->completion_lock); + if (canceled != 0) + io_cqring_ev_posted(ctx); + return canceled != 0; }

static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) { unsigned long index; - struct io_identify *iod; + struct creds *creds;

mutex_lock(&ctx->uring_lock); percpu_ref_kill(&ctx->refs); - /* if force is set, the ring is going away. always drop after that */ - - if (WARN_ON_ONCE((ctx->flags & IORING_SETUP_SQPOLL) && !ctx->sqo_dead)) - ctx->sqo_dead = 1; - - ctx->cq_overflow_flushed = 1; if (ctx->rings) - __io_cqring_overflow_flush(ctx, true, NULL, NULL); + __io_cqring_overflow_flush(ctx, true); + xa_for_each(&ctx->personalities, index, creds) + io_unregister_personality(ctx, index); mutex_unlock(&ctx->uring_lock);

- io_kill_timeouts(ctx, NULL, NULL); - io_poll_remove_all(ctx, NULL, NULL); - - if (ctx->io_wq) - io_wq_cancel_cb(ctx->io_wq, io_cancel_ctx_cb, ctx, true); + io_kill_timeouts(ctx, NULL, true); + io_poll_remove_all(ctx, NULL, true);

/* if we failed setting up the ctx, we might not have any rings */ io_iopoll_try_reap_events(ctx); - xa_for_each(&ctx->personalities, index, iod) - io_unregister_personality(ctx, index); - - /* - * Do this upfront, so we won't have a grace period where the ring - * is closed but resources aren't reaped yet. This can cause - * spurious failure in setting up a new ring. - */ - io_unaccount_mem(ctx, ring_pages(ctx->sq_entries, ctx->cq_entries), - ACCT_LOCKED);

INIT_WORK(&ctx->exit_work, io_ring_exit_work); /* @@ -8647,352 +9443,290 @@ static int io_uring_release(struct inode *inode, struct file *file)

struct io_task_cancel { struct task_struct *task; - struct files_struct *files; + bool all; };

static bool io_cancel_task_cb(struct io_wq_work *work, void *data) { struct io_kiocb *req = container_of(work, struct io_kiocb, work); struct io_task_cancel *cancel = data; - bool ret; - - if (cancel->files && (req->flags & REQ_F_LINK_TIMEOUT)) { - unsigned long flags; - struct io_ring_ctx *ctx = req->ctx;

- /* protect against races with linked timeouts */ - spin_lock_irqsave(&ctx->completion_lock, flags); - ret = io_match_task(req, cancel->task, cancel->files); - spin_unlock_irqrestore(&ctx->completion_lock, flags); - } else { - ret = io_match_task(req, cancel->task, cancel->files); - } - return ret; + return io_match_task_safe(req, cancel->task, cancel->all); }

-static void io_cancel_defer_files(struct io_ring_ctx *ctx, - struct task_struct *task, - struct files_struct *files) +static bool io_cancel_defer_files(struct io_ring_ctx *ctx, + struct task_struct *task, bool cancel_all) { - struct io_defer_entry *de = NULL; + struct io_defer_entry *de; LIST_HEAD(list);

- spin_lock_irq(&ctx->completion_lock); + spin_lock(&ctx->completion_lock); list_for_each_entry_reverse(de, &ctx->defer_list, list) { - if (io_match_task(de->req, task, files)) { + if (io_match_task_safe(de->req, task, cancel_all)) { list_cut_position(&list, &ctx->defer_list, &de->list); break; } } - spin_unlock_irq(&ctx->completion_lock); + spin_unlock(&ctx->completion_lock); + if (list_empty(&list)) + return false;

while (!list_empty(&list)) { de = list_first_entry(&list, struct io_defer_entry, list); list_del_init(&de->list); - req_set_fail_links(de->req); - io_put_req(de->req); - io_req_complete(de->req, -ECANCELED); + io_req_complete_failed(de->req, -ECANCELED); kfree(de); } + return true; }

-static int io_uring_count_inflight(struct io_ring_ctx *ctx, - struct task_struct *task, - struct files_struct *files) -{ - struct io_kiocb *req; - int cnt = 0; - - spin_lock_irq(&ctx->inflight_lock); - list_for_each_entry(req, &ctx->inflight_list, inflight_entry) - cnt += io_match_task(req, task, files); - spin_unlock_irq(&ctx->inflight_lock); - return cnt; -} - -static void io_uring_cancel_files(struct io_ring_ctx *ctx, - struct task_struct *task, - struct files_struct *files) +static bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx) { - while (!list_empty_careful(&ctx->inflight_list)) { - struct io_task_cancel cancel = { .task = task, .files = files }; - DEFINE_WAIT(wait); - int inflight; - - inflight = io_uring_count_inflight(ctx, task, files); - if (!inflight) - break; + struct io_tctx_node *node; + enum io_wq_cancel cret; + bool ret = false;

- io_wq_cancel_cb(ctx->io_wq, io_cancel_task_cb, &cancel, true); - io_poll_remove_all(ctx, task, files); - io_kill_timeouts(ctx, task, files); - /* cancellations _may_ trigger task work */ - io_run_task_work(); + mutex_lock(&ctx->uring_lock); + list_for_each_entry(node, &ctx->tctx_list, ctx_node) { + struct io_uring_task *tctx = node->task->io_uring;

- prepare_to_wait(&task->io_uring->wait, &wait, - TASK_UNINTERRUPTIBLE); - if (inflight == io_uring_count_inflight(ctx, task, files)) - schedule(); - finish_wait(&task->io_uring->wait, &wait); + /* + * io_wq will stay alive while we hold uring_lock, because it's + * killed after ctx nodes, which requires to take the lock. + */ + if (!tctx || !tctx->io_wq) + continue; + cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true); + ret |= (cret != IO_WQ_CANCEL_NOTFOUND); } + mutex_unlock(&ctx->uring_lock); + + return ret; }

-static void __io_uring_cancel_task_requests(struct io_ring_ctx *ctx, - struct task_struct *task) +static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx, + struct task_struct *task, + bool cancel_all) { + struct io_task_cancel cancel = { .task = task, .all = cancel_all, }; + struct io_uring_task *tctx = task ? task->io_uring : NULL; + while (1) { - struct io_task_cancel cancel = { .task = task, .files = NULL, }; enum io_wq_cancel cret; bool ret = false;

- cret = io_wq_cancel_cb(ctx->io_wq, io_cancel_task_cb, &cancel, true); - if (cret != IO_WQ_CANCEL_NOTFOUND) - ret = true; + if (!task) { + ret |= io_uring_try_cancel_iowq(ctx); + } else if (tctx && tctx->io_wq) { + /* + * Cancels requests of all rings, not only @ctx, but + * it's fine as the task is in exit/exec. + */ + cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb, + &cancel, true); + ret |= (cret != IO_WQ_CANCEL_NOTFOUND); + }

/* SQPOLL thread does its own polling */ - if (!(ctx->flags & IORING_SETUP_SQPOLL)) { + if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) || + (ctx->sq_data && ctx->sq_data->thread == current)) { while (!list_empty_careful(&ctx->iopoll_list)) { io_iopoll_try_reap_events(ctx); ret = true; } }

- ret |= io_poll_remove_all(ctx, task, NULL); - ret |= io_kill_timeouts(ctx, task, NULL); + ret |= io_cancel_defer_files(ctx, task, cancel_all); + ret |= io_poll_remove_all(ctx, task, cancel_all); + ret |= io_kill_timeouts(ctx, task, cancel_all); + if (task) + ret |= io_run_task_work(); if (!ret) break; - io_run_task_work(); cond_resched(); } }

-static void io_disable_sqo_submit(struct io_ring_ctx *ctx) -{ - mutex_lock(&ctx->uring_lock); - ctx->sqo_dead = 1; - if (ctx->flags & IORING_SETUP_R_DISABLED) - io_sq_offload_start(ctx); - mutex_unlock(&ctx->uring_lock); - - /* make sure callers enter the ring to get error */ - if (ctx->rings) - io_ring_set_wakeup_flag(ctx); -} - -/* - * We need to iteratively cancel requests, in case a request has dependent - * hard links. These persist even for failure of cancelations, hence keep - * looping until none are found. - */ -static void io_uring_cancel_task_requests(struct io_ring_ctx *ctx, - struct files_struct *files) -{ - struct task_struct *task = current; - - if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) { - io_disable_sqo_submit(ctx); - task = ctx->sq_data->thread; - atomic_inc(&task->io_uring->in_idle); - io_sq_thread_park(ctx->sq_data); - } - - io_cancel_defer_files(ctx, task, files); - io_cqring_overflow_flush(ctx, true, task, files); - - if (!files) - __io_uring_cancel_task_requests(ctx, task); - else - io_uring_cancel_files(ctx, task, files); - - if ((ctx->flags & IORING_SETUP_SQPOLL) && ctx->sq_data) { - atomic_dec(&task->io_uring->in_idle); - io_sq_thread_unpark(ctx->sq_data); - } -} - -/* - * Note that this task has used io_uring. We use it for cancelation purposes. - */ -static int io_uring_add_task_file(struct io_ring_ctx *ctx, struct file *file) +static int __io_uring_add_tctx_node(struct io_ring_ctx *ctx) { struct io_uring_task *tctx = current->io_uring; + struct io_tctx_node *node; int ret;

if (unlikely(!tctx)) { - ret = io_uring_alloc_task_context(current); + ret = io_uring_alloc_task_context(current, ctx); if (unlikely(ret)) return ret; + tctx = current->io_uring; - } - if (tctx->last != file) { - void *old = xa_load(&tctx->xa, (unsigned long)file); + if (ctx->iowq_limits_set) { + unsigned int limits[2] = { ctx->iowq_limits[0], + ctx->iowq_limits[1], };

- if (!old) { - get_file(file); - ret = xa_err(xa_store(&tctx->xa, (unsigned long)file, - file, GFP_KERNEL)); - if (ret) { - fput(file); + ret = io_wq_max_workers(tctx->io_wq, limits); + if (ret) return ret; - } } - tctx->last = file; } + if (!xa_load(&tctx->xa, (unsigned long)ctx)) { + node = kmalloc(sizeof(*node), GFP_KERNEL); + if (!node) + return -ENOMEM; + node->ctx = ctx; + node->task = current;

- /* - * This is race safe in that the task itself is doing this, hence it - * cannot be going through the exit/cancel paths at the same time. - * This cannot be modified while exit/cancel is running. - */ - if (!tctx->sqpoll && (ctx->flags & IORING_SETUP_SQPOLL)) - tctx->sqpoll = true; + ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx, + node, GFP_KERNEL)); + if (ret) { + kfree(node); + return ret; + }

+ mutex_lock(&ctx->uring_lock); + list_add(&node->ctx_node, &ctx->tctx_list); + mutex_unlock(&ctx->uring_lock); + } + tctx->last = ctx; return 0; }

/* - * Remove this io_uring_file -> task mapping. + * Note that this task has used io_uring. We use it for cancelation purposes. */ -static void io_uring_del_task_file(struct file *file) +static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx) { struct io_uring_task *tctx = current->io_uring;

- if (tctx->last == file) - tctx->last = NULL; - file = xa_erase(&tctx->xa, (unsigned long)file); - if (file) - fput(file); + if (likely(tctx && tctx->last == ctx)) + return 0; + return __io_uring_add_tctx_node(ctx); }

-static void io_uring_remove_task_files(struct io_uring_task *tctx) +/* + * Remove this io_uring_file -> task mapping. + */ +static void io_uring_del_tctx_node(unsigned long index) { - struct file *file; - unsigned long index; + struct io_uring_task *tctx = current->io_uring; + struct io_tctx_node *node;

- xa_for_each(&tctx->xa, index, file) - io_uring_del_task_file(file); -} + if (!tctx) + return; + node = xa_erase(&tctx->xa, index); + if (!node) + return;

-void __io_uring_files_cancel(struct files_struct *files) -{ - struct io_uring_task *tctx = current->io_uring; - struct file *file; - unsigned long index; + WARN_ON_ONCE(current != node->task); + WARN_ON_ONCE(list_empty(&node->ctx_node));

- /* make sure overflow events are dropped */ - atomic_inc(&tctx->in_idle); - xa_for_each(&tctx->xa, index, file) - io_uring_cancel_task_requests(file->private_data, files); - atomic_dec(&tctx->in_idle); + mutex_lock(&node->ctx->uring_lock); + list_del(&node->ctx_node); + mutex_unlock(&node->ctx->uring_lock);

- if (files) - io_uring_remove_task_files(tctx); + if (tctx->last == node->ctx) + tctx->last = NULL; + kfree(node); }

-static s64 tctx_inflight(struct io_uring_task *tctx) +static void io_uring_clean_tctx(struct io_uring_task *tctx) { + struct io_wq *wq = tctx->io_wq; + struct io_tctx_node *node; unsigned long index; - struct file *file; - s64 inflight; - - inflight = percpu_counter_sum(&tctx->inflight); - if (!tctx->sqpoll) - return inflight;

- /* - * If we have SQPOLL rings, then we need to iterate and find them, and - * add the pending count for those. - */ - xa_for_each(&tctx->xa, index, file) { - struct io_ring_ctx *ctx = file->private_data; - - if (ctx->flags & IORING_SETUP_SQPOLL) { - struct io_uring_task *__tctx = ctx->sqo_task->io_uring; - - inflight += percpu_counter_sum(&__tctx->inflight); - } + xa_for_each(&tctx->xa, index, node) { + io_uring_del_tctx_node(index); + cond_resched(); + } + if (wq) { + /* + * Must be after io_uring_del_task_file() (removes nodes under + * uring_lock) to avoid race with io_uring_try_cancel_iowq(). + */ + io_wq_put_and_exit(wq); + tctx->io_wq = NULL; } +}

- return inflight; +static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked) +{ + if (tracked) + return atomic_read(&tctx->inflight_tracked); + return percpu_counter_sum(&tctx->inflight); }

/* - * Find any io_uring fd that this task has registered or done IO on, and cancel - * requests. + * Find any io_uring ctx that this task has registered or done IO on, and cancel + * requests. @sqd should be not-null IFF it's an SQPOLL thread cancellation. */ -void __io_uring_task_cancel(void) +static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd) { struct io_uring_task *tctx = current->io_uring; - DEFINE_WAIT(wait); + struct io_ring_ctx *ctx; s64 inflight; + DEFINE_WAIT(wait);

- /* make sure overflow events are dropped */ - atomic_inc(&tctx->in_idle); + WARN_ON_ONCE(sqd && sqd->thread != current);

- /* trigger io_disable_sqo_submit() */ - if (tctx->sqpoll) - __io_uring_files_cancel(NULL); + if (!current->io_uring) + return; + if (tctx->io_wq) + io_wq_exit_start(tctx->io_wq);

+ atomic_inc(&tctx->in_idle); do { + io_uring_drop_tctx_refs(current); /* read completions before cancelations */ - inflight = tctx_inflight(tctx); + inflight = tctx_inflight(tctx, !cancel_all); if (!inflight) break; - __io_uring_files_cancel(NULL); - - prepare_to_wait(&tctx->wait, &wait, TASK_UNINTERRUPTIBLE); - - /* - * If we've seen completions, retry without waiting. This - * avoids a race where a completion comes in before we did - * prepare_to_wait(). - */ - if (inflight == tctx_inflight(tctx)) - schedule(); - finish_wait(&tctx->wait, &wait); - } while (1); - - atomic_dec(&tctx->in_idle); - - io_uring_remove_task_files(tctx); -} - -static int io_uring_flush(struct file *file, void *data) -{ - struct io_uring_task *tctx = current->io_uring; - struct io_ring_ctx *ctx = file->private_data; - - if (fatal_signal_pending(current) || (current->flags & PF_EXITING)) - io_uring_cancel_task_requests(ctx, NULL);

- if (!tctx) - return 0; + if (!sqd) { + struct io_tctx_node *node; + unsigned long index;

- /* we should have cancelled and erased it before PF_EXITING */ - WARN_ON_ONCE((current->flags & PF_EXITING) && - xa_load(&tctx->xa, (unsigned long)file)); + xa_for_each(&tctx->xa, index, node) { + /* sqpoll task will cancel all its requests */ + if (node->ctx->sq_data) + continue; + io_uring_try_cancel_requests(node->ctx, current, + cancel_all); + } + } else { + list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) + io_uring_try_cancel_requests(ctx, current, + cancel_all); + }

- /* - * fput() is pending, will be 2 if the only other ref is our potential - * task file note. If the task is exiting, drop regardless of count. - */ - if (atomic_long_read(&file->f_count) != 2) - return 0; + prepare_to_wait(&tctx->wait, &wait, TASK_INTERRUPTIBLE); + io_run_task_work(); + io_uring_drop_tctx_refs(current);

- if (ctx->flags & IORING_SETUP_SQPOLL) { - /* there is only one file note, which is owned by sqo_task */ - WARN_ON_ONCE(ctx->sqo_task != current && - xa_load(&tctx->xa, (unsigned long)file)); - /* sqo_dead check is for when this happens after cancellation */ - WARN_ON_ONCE(ctx->sqo_task == current && !ctx->sqo_dead && - !xa_load(&tctx->xa, (unsigned long)file)); + /* + * If we've seen completions, retry without waiting. This + * avoids a race where a completion comes in before we did + * prepare_to_wait(). + */ + if (inflight == tctx_inflight(tctx, !cancel_all)) + schedule(); + finish_wait(&tctx->wait, &wait); + } while (1);

- io_disable_sqo_submit(ctx); + io_uring_clean_tctx(tctx); + if (cancel_all) { + /* + * We shouldn't run task_works after cancel, so just leave + * ->in_idle set for normal exit. + */ + atomic_dec(&tctx->in_idle); + /* for exec all current's requests should be gone, kill tctx */ + __io_uring_free(current); } +}

- if (!(ctx->flags & IORING_SETUP_SQPOLL) || ctx->sqo_task == current) - io_uring_del_task_file(file); - return 0; +void __io_uring_cancel(bool cancel_all) +{ + io_uring_cancel_generic(cancel_all, NULL); }

static void *io_uring_validate_mmap_request(struct file *file, @@ -9067,60 +9801,84 @@ static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,

static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx) { - int ret = 0; DEFINE_WAIT(wait);

do { if (!io_sqring_full(ctx)) break; - prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);

- if (unlikely(ctx->sqo_dead)) { - ret = -EOWNERDEAD; - break; - } - if (!io_sqring_full(ctx)) break; - schedule(); } while (!signal_pending(current));

finish_wait(&ctx->sqo_sq_wait, &wait); - return ret; + return 0; +} + +static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz, + struct __kernel_timespec __user **ts, + const sigset_t __user **sig) +{ + struct io_uring_getevents_arg arg; + + /* + * If EXT_ARG isn't set, then we have no timespec and the argp pointer + * is just a pointer to the sigset_t. + */ + if (!(flags & IORING_ENTER_EXT_ARG)) { + *sig = (const sigset_t __user *) argp; + *ts = NULL; + return 0; + } + + /* + * EXT_ARG is set - ensure we agree on the size of it and copy in our + * timespec and sigset_t pointers if good. + */ + if (*argsz != sizeof(arg)) + return -EINVAL; + if (copy_from_user(&arg, argp, sizeof(arg))) + return -EFAULT; + if (arg.pad) + return -EINVAL; + *sig = u64_to_user_ptr(arg.sigmask); + *argsz = arg.sigmask_sz; + *ts = u64_to_user_ptr(arg.ts); + return 0; }

SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, - u32, min_complete, u32, flags, const sigset_t __user *, sig, - size_t, sigsz) + u32, min_complete, u32, flags, const void __user *, argp, + size_t, argsz) { struct io_ring_ctx *ctx; - long ret = -EBADF; int submitted = 0; struct fd f; + long ret;

io_run_task_work();

- if (flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP | - IORING_ENTER_SQ_WAIT)) + if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP | + IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG))) return -EINVAL;

f = fdget(fd); - if (!f.file) + if (unlikely(!f.file)) return -EBADF;

ret = -EOPNOTSUPP; - if (f.file->f_op != &io_uring_fops) + if (unlikely(f.file->f_op != &io_uring_fops)) goto out_fput;

ret = -ENXIO; ctx = f.file->private_data; - if (!percpu_ref_tryget(&ctx->refs)) + if (unlikely(!percpu_ref_tryget(&ctx->refs))) goto out_fput;

ret = -EBADFD; - if (ctx->flags & IORING_SETUP_R_DISABLED) + if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED)) goto out;

/* @@ -9130,9 +9888,9 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, */ ret = 0; if (ctx->flags & IORING_SETUP_SQPOLL) { - io_cqring_overflow_flush(ctx, false, NULL, NULL); + io_cqring_overflow_flush(ctx);

- if (unlikely(ctx->sqo_dead)) { + if (unlikely(ctx->sq_data->thread == NULL)) { ret = -EOWNERDEAD; goto out; } @@ -9145,7 +9903,7 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, } submitted = to_submit; } else if (to_submit) { - ret = io_uring_add_task_file(ctx, f.file); + ret = io_uring_add_tctx_node(ctx); if (unlikely(ret)) goto out; mutex_lock(&ctx->uring_lock); @@ -9156,6 +9914,13 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, goto out; } if (flags & IORING_ENTER_GETEVENTS) { + const sigset_t __user *sig; + struct __kernel_timespec __user *ts; + + ret = io_get_ext_arg(flags, argp, &argsz, &ts, &sig); + if (unlikely(ret)) + goto out; + min_complete = min(min_complete, ctx->cq_entries);

/* @@ -9168,7 +9933,7 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, !(ctx->flags & IORING_SETUP_SQPOLL)) { ret = io_iopoll_check(ctx, min_complete); } else { - ret = io_cqring_wait(ctx, min_complete, sig, sigsz); + ret = io_cqring_wait(ctx, min_complete, sig, argsz, ts); } }

@@ -9181,9 +9946,8 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,

#ifdef CONFIG_PROC_FS static int io_uring_show_cred(struct seq_file *m, unsigned int id, - const struct io_identity *iod) + const struct cred *cred) { - const struct cred *cred = iod->creds; struct user_namespace *uns = seq_user_ns(m); struct group_info *gi; kernel_cap_t cap; @@ -9227,18 +9991,18 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) */ has_lock = mutex_trylock(&ctx->uring_lock);

- if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) + if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) { sq = ctx->sq_data; + if (!sq->thread) + sq = NULL; + }

seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1); seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1); seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files); for (i = 0; has_lock && i < ctx->nr_user_files; i++) { - struct fixed_file_table *table; - struct file *f; + struct file *f = io_file_from_index(ctx, i);

- table = &ctx->file_data->table[i >> IORING_FILE_TABLE_SHIFT]; - f = table->files[i & IORING_FILE_TABLE_MASK]; if (f) seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname); else @@ -9246,21 +10010,21 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) } seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs); for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) { - struct io_mapped_ubuf *buf = &ctx->user_bufs[i]; + struct io_mapped_ubuf *buf = ctx->user_bufs[i]; + unsigned int len = buf->ubuf_end - buf->ubuf;

- seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, - (unsigned int) buf->len); + seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len); } if (has_lock && !xa_empty(&ctx->personalities)) { unsigned long index; - const struct io_identity *iod; + const struct cred *cred;

seq_printf(m, "Personalities:\n"); - xa_for_each(&ctx->personalities, index, iod) - io_uring_show_cred(m, index, iod); + xa_for_each(&ctx->personalities, index, cred) + io_uring_show_cred(m, index, cred); } seq_printf(m, "PollList:\n"); - spin_lock_irq(&ctx->completion_lock); + spin_lock(&ctx->completion_lock); for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) { struct hlist_head *list = &ctx->cancel_hash[i]; struct io_kiocb *req; @@ -9269,7 +10033,7 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) seq_printf(m, " op=%d, task_works=%d\n", req->opcode, req->task->task_works != NULL); } - spin_unlock_irq(&ctx->completion_lock); + spin_unlock(&ctx->completion_lock); if (has_lock) mutex_unlock(&ctx->uring_lock); } @@ -9287,14 +10051,12 @@ static void io_uring_show_fdinfo(struct seq_file *m, struct file *f)

static const struct file_operations io_uring_fops = { .release = io_uring_release, - .flush = io_uring_flush, .mmap = io_uring_mmap, #ifndef CONFIG_MMU .get_unmapped_area = io_uring_nommu_get_unmapped_area, .mmap_capabilities = io_uring_nommu_mmap_capabilities, #endif .poll = io_uring_poll, - .fasync = io_uring_fasync, #ifdef CONFIG_PROC_FS .show_fdinfo = io_uring_show_fdinfo, #endif @@ -9324,8 +10086,6 @@ static int io_allocate_scq_urings(struct io_ring_ctx *ctx, rings->cq_ring_mask = p->cq_entries - 1; rings->sq_ring_entries = p->sq_entries; rings->cq_ring_entries = p->cq_entries; - ctx->sq_mask = rings->sq_ring_mask; - ctx->cq_mask = rings->cq_ring_mask;

size = array_size(sizeof(struct io_uring_sqe), p->sq_entries); if (size == SIZE_MAX) { @@ -9352,7 +10112,7 @@ static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file) if (fd < 0) return fd;

- ret = io_uring_add_task_file(ctx, file); + ret = io_uring_add_tctx_node(ctx); if (ret) { put_unused_fd(fd); return ret; @@ -9395,10 +10155,8 @@ static struct file *io_uring_get_file(struct io_ring_ctx *ctx) static int io_uring_create(unsigned entries, struct io_uring_params *p, struct io_uring_params __user *params) { - struct user_struct *user = NULL; struct io_ring_ctx *ctx; struct file *file; - bool limit_mem; int ret;

if (!entries) @@ -9438,34 +10196,12 @@ static int io_uring_create(unsigned entries, struct io_uring_params *p, p->cq_entries = 2 * p->sq_entries; }

- user = get_uid(current_user()); - limit_mem = !capable(CAP_IPC_LOCK); - - if (limit_mem) { - ret = __io_account_mem(user, - ring_pages(p->sq_entries, p->cq_entries)); - if (ret) { - free_uid(user); - return ret; - } - } - ctx = io_ring_ctx_alloc(p); - if (!ctx) { - if (limit_mem) - __io_unaccount_mem(user, ring_pages(p->sq_entries, - p->cq_entries)); - free_uid(user); + if (!ctx) return -ENOMEM; - } ctx->compat = in_compat_syscall(); - ctx->user = user; - ctx->creds = get_current_cred(); -#ifdef CONFIG_AUDIT - ctx->loginuid = current->loginuid; - ctx->sessionid = current->sessionid; -#endif - ctx->sqo_task = get_task_struct(current); + if (!capable(CAP_IPC_LOCK)) + ctx->user = get_uid(current_user());

/* * This is just grabbed for accounting purposes. When a process exits, @@ -9476,35 +10212,6 @@ static int io_uring_create(unsigned entries, struct io_uring_params *p, mmgrab(current->mm); ctx->mm_account = current->mm;

-#ifdef CONFIG_BLK_CGROUP - /* - * The sq thread will belong to the original cgroup it was inited in. - * If the cgroup goes offline (e.g. disabling the io controller), then - * issued bios will be associated with the closest cgroup later in the - * block layer. - */ - rcu_read_lock(); - ctx->sqo_blkcg_css = blkcg_css(); - ret = css_tryget_online(ctx->sqo_blkcg_css); - rcu_read_unlock(); - if (!ret) { - /* don't init against a dying cgroup, have the user try again */ - ctx->sqo_blkcg_css = NULL; - ret = -ENODEV; - goto err; - } -#endif - - /* - * Account memory _before_ installing the file descriptor. Once - * the descriptor is installed, it can get closed at any time. Also - * do this before hitting the general error path, as ring freeing - * will un-account as well. - */ - io_account_mem(ctx, ring_pages(p->sq_entries, p->cq_entries), - ACCT_LOCKED); - ctx->limit_mem = limit_mem; - ret = io_allocate_scq_urings(ctx, p); if (ret) goto err; @@ -9512,9 +10219,11 @@ static int io_uring_create(unsigned entries, struct io_uring_params *p, ret = io_sq_offload_create(ctx, p); if (ret) goto err; - - if (!(p->flags & IORING_SETUP_R_DISABLED)) - io_sq_offload_start(ctx); + /* always set a rsrc node */ + ret = io_rsrc_node_switch_start(ctx); + if (ret) + goto err; + io_rsrc_node_switch(ctx, NULL);

memset(&p->sq_off, 0, sizeof(p->sq_off)); p->sq_off.head = offsetof(struct io_rings, sq.head); @@ -9537,7 +10246,9 @@ static int io_uring_create(unsigned entries, struct io_uring_params *p, p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP | IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS | IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL | - IORING_FEAT_POLL_32BITS; + IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED | + IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS | + IORING_FEAT_RSRC_TAGS;

if (copy_to_user(params, p, sizeof(*p))) { ret = -EFAULT; @@ -9556,7 +10267,6 @@ static int io_uring_create(unsigned entries, struct io_uring_params *p, */ ret = io_uring_install_fd(ctx, file); if (ret < 0) { - io_disable_sqo_submit(ctx); /* fput will clean it up */ fput(file); return ret; @@ -9565,7 +10275,6 @@ static int io_uring_create(unsigned entries, struct io_uring_params *p, trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags); return ret; err: - io_disable_sqo_submit(ctx); io_ring_ctx_wait_and_kill(ctx); return ret; } @@ -9643,22 +10352,16 @@ static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args)

static int io_register_personality(struct io_ring_ctx *ctx) { - struct io_identity *iod; + const struct cred *creds; u32 id; int ret;

- iod = kmalloc(sizeof(*iod), GFP_KERNEL); - if (unlikely(!iod)) - return -ENOMEM; - - io_init_identity(iod); - iod->creds = get_current_cred(); + creds = get_current_cred();

- ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)iod, + ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds, XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL); if (ret < 0) { - put_cred(iod->creds); - kfree(iod); + put_cred(creds); return ret; } return id; @@ -9742,24 +10445,273 @@ static int io_register_enable_rings(struct io_ring_ctx *ctx) if (ctx->restrictions.registered) ctx->restricted = 1;

- io_sq_offload_start(ctx); + ctx->flags &= ~IORING_SETUP_R_DISABLED; + if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait)) + wake_up(&ctx->sq_data->wait); + return 0; +} + +static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type, + struct io_uring_rsrc_update2 *up, + unsigned nr_args) +{ + __u32 tmp; + int err; + + if (check_add_overflow(up->offset, nr_args, &tmp)) + return -EOVERFLOW; + err = io_rsrc_node_switch_start(ctx); + if (err) + return err; + + switch (type) { + case IORING_RSRC_FILE: + return __io_sqe_files_update(ctx, up, nr_args); + case IORING_RSRC_BUFFER: + return __io_sqe_buffers_update(ctx, up, nr_args); + } + return -EINVAL; +} + +static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg, + unsigned nr_args) +{ + struct io_uring_rsrc_update2 up; + + if (!nr_args) + return -EINVAL; + memset(&up, 0, sizeof(up)); + if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update))) + return -EFAULT; + if (up.resv || up.resv2) + return -EINVAL; + return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args); +} + +static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg, + unsigned size, unsigned type) +{ + struct io_uring_rsrc_update2 up; + + if (size != sizeof(up)) + return -EINVAL; + if (copy_from_user(&up, arg, sizeof(up))) + return -EFAULT; + if (!up.nr || up.resv || up.resv2) + return -EINVAL; + return __io_register_rsrc_update(ctx, type, &up, up.nr); +} + +static int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg, + unsigned int size, unsigned int type) +{ + struct io_uring_rsrc_register rr; + + /* keep it extendible */ + if (size != sizeof(rr)) + return -EINVAL; + + memset(&rr, 0, sizeof(rr)); + if (copy_from_user(&rr, arg, size)) + return -EFAULT; + if (!rr.nr || rr.resv || rr.resv2) + return -EINVAL; + + switch (type) { + case IORING_RSRC_FILE: + return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data), + rr.nr, u64_to_user_ptr(rr.tags)); + case IORING_RSRC_BUFFER: + return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data), + rr.nr, u64_to_user_ptr(rr.tags)); + } + return -EINVAL; +} + +static int io_register_iowq_aff(struct io_ring_ctx *ctx, void __user *arg, + unsigned len) +{ + struct io_uring_task *tctx = current->io_uring; + cpumask_var_t new_mask; + int ret; + + if (!tctx || !tctx->io_wq) + return -EINVAL; + + if (!alloc_cpumask_var(&new_mask, GFP_KERNEL)) + return -ENOMEM; + + cpumask_clear(new_mask); + if (len > cpumask_size()) + len = cpumask_size(); + +#ifdef CONFIG_COMPAT + if (in_compat_syscall()) { + ret = compat_get_bitmap(cpumask_bits(new_mask), + (const compat_ulong_t __user *)arg, + len * 8 /* CHAR_BIT */); + } else { + ret = copy_from_user(new_mask, arg, len); + } +#else + ret = copy_from_user(new_mask, arg, len); +#endif + + if (ret) { + free_cpumask_var(new_mask); + return -EFAULT; + } + + ret = io_wq_cpu_affinity(tctx->io_wq, new_mask); + free_cpumask_var(new_mask); + return ret; +} + +static int io_unregister_iowq_aff(struct io_ring_ctx *ctx) +{ + struct io_uring_task *tctx = current->io_uring; + + if (!tctx || !tctx->io_wq) + return -EINVAL; + + return io_wq_cpu_affinity(tctx->io_wq, NULL); +} + +static int io_register_iowq_max_workers(struct io_ring_ctx *ctx, + void __user *arg) + __must_hold(&ctx->uring_lock) +{ + struct io_tctx_node *node; + struct io_uring_task *tctx = NULL; + struct io_sq_data *sqd = NULL; + __u32 new_count[2]; + int i, ret; + + if (copy_from_user(new_count, arg, sizeof(new_count))) + return -EFAULT; + for (i = 0; i < ARRAY_SIZE(new_count); i++) + if (new_count[i] > INT_MAX) + return -EINVAL; + + if (ctx->flags & IORING_SETUP_SQPOLL) { + sqd = ctx->sq_data; + if (sqd) { + /* + * Observe the correct sqd->lock -> ctx->uring_lock + * ordering. Fine to drop uring_lock here, we hold + * a ref to the ctx. + */ + refcount_inc(&sqd->refs); + mutex_unlock(&ctx->uring_lock); + mutex_lock(&sqd->lock); + mutex_lock(&ctx->uring_lock); + if (sqd->thread) + tctx = sqd->thread->io_uring; + } + } else { + tctx = current->io_uring; + } + + BUILD_BUG_ON(sizeof(new_count) != sizeof(ctx->iowq_limits)); + + for (i = 0; i < ARRAY_SIZE(new_count); i++) + if (new_count[i]) + ctx->iowq_limits[i] = new_count[i]; + ctx->iowq_limits_set = true; + + ret = -EINVAL; + if (tctx && tctx->io_wq) { + ret = io_wq_max_workers(tctx->io_wq, new_count); + if (ret) + goto err; + } else { + memset(new_count, 0, sizeof(new_count)); + } + + if (sqd) { + mutex_unlock(&sqd->lock); + io_put_sq_data(sqd); + } + + if (copy_to_user(arg, new_count, sizeof(new_count))) + return -EFAULT; + + /* that's it for SQPOLL, only the SQPOLL task creates requests */ + if (sqd) + return 0; + + /* now propagate the restriction to all registered users */ + list_for_each_entry(node, &ctx->tctx_list, ctx_node) { + struct io_uring_task *tctx = node->task->io_uring; + + if (WARN_ON_ONCE(!tctx->io_wq)) + continue; + + for (i = 0; i < ARRAY_SIZE(new_count); i++) + new_count[i] = ctx->iowq_limits[i]; + /* ignore errors, it always returns zero anyway */ + (void)io_wq_max_workers(tctx->io_wq, new_count); + } return 0; +err: + if (sqd) { + mutex_unlock(&sqd->lock); + io_put_sq_data(sqd); + } + return ret; }

static bool io_register_op_must_quiesce(int op) { switch (op) { + case IORING_REGISTER_BUFFERS: + case IORING_UNREGISTER_BUFFERS: + case IORING_REGISTER_FILES: case IORING_UNREGISTER_FILES: case IORING_REGISTER_FILES_UPDATE: case IORING_REGISTER_PROBE: case IORING_REGISTER_PERSONALITY: case IORING_UNREGISTER_PERSONALITY: + case IORING_REGISTER_FILES2: + case IORING_REGISTER_FILES_UPDATE2: + case IORING_REGISTER_BUFFERS2: + case IORING_REGISTER_BUFFERS_UPDATE: + case IORING_REGISTER_IOWQ_AFF: + case IORING_UNREGISTER_IOWQ_AFF: + case IORING_REGISTER_IOWQ_MAX_WORKERS: return false; default: return true; } }

+static int io_ctx_quiesce(struct io_ring_ctx *ctx) +{ + long ret; + + percpu_ref_kill(&ctx->refs); + + /* + * Drop uring mutex before waiting for references to exit. If another + * thread is currently inside io_uring_enter() it might need to grab the + * uring_lock to make progress. If we hold it here across the drain + * wait, then we can deadlock. It's safe to drop the mutex here, since + * no new references will come in after we've killed the percpu ref. + */ + mutex_unlock(&ctx->uring_lock); + do { + ret = wait_for_completion_interruptible(&ctx->ref_comp); + if (!ret) + break; + ret = io_run_task_work_sig(); + } while (ret >= 0); + mutex_lock(&ctx->uring_lock); + + if (ret) + io_refs_resurrect(&ctx->refs, &ctx->ref_comp); + return ret; +} + static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, void __user *arg, unsigned nr_args) __releases(ctx->uring_lock) @@ -9775,58 +10727,32 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, if (percpu_ref_is_dying(&ctx->refs)) return -ENXIO;

- if (io_register_op_must_quiesce(opcode)) { - percpu_ref_kill(&ctx->refs); - - /* - * Drop uring mutex before waiting for references to exit. If - * another thread is currently inside io_uring_enter() it might - * need to grab the uring_lock to make progress. If we hold it - * here across the drain wait, then we can deadlock. It's safe - * to drop the mutex here, since no new references will come in - * after we've killed the percpu ref. - */ - mutex_unlock(&ctx->uring_lock); - do { - ret = wait_for_completion_interruptible(&ctx->ref_comp); - if (!ret) - break; - ret = io_run_task_work_sig(); - if (ret < 0) - break; - } while (1); - mutex_lock(&ctx->uring_lock); - - if (ret) { - io_refs_resurrect(&ctx->refs, &ctx->ref_comp); - return ret; - } - } - if (ctx->restricted) { - if (opcode >= IORING_REGISTER_LAST) { - ret = -EINVAL; - goto out; - } + if (opcode >= IORING_REGISTER_LAST) + return -EINVAL; + opcode = array_index_nospec(opcode, IORING_REGISTER_LAST); + if (!test_bit(opcode, ctx->restrictions.register_op)) + return -EACCES; + }

- if (!test_bit(opcode, ctx->restrictions.register_op)) { - ret = -EACCES; - goto out; - } + if (io_register_op_must_quiesce(opcode)) { + ret = io_ctx_quiesce(ctx); + if (ret) + return ret; }

switch (opcode) { case IORING_REGISTER_BUFFERS: - ret = io_sqe_buffer_register(ctx, arg, nr_args); + ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL); break; case IORING_UNREGISTER_BUFFERS: ret = -EINVAL; if (arg || nr_args) break; - ret = io_sqe_buffer_unregister(ctx); + ret = io_sqe_buffers_unregister(ctx); break; case IORING_REGISTER_FILES: - ret = io_sqe_files_register(ctx, arg, nr_args); + ret = io_sqe_files_register(ctx, arg, nr_args, NULL); break; case IORING_UNREGISTER_FILES: ret = -EINVAL; @@ -9835,7 +10761,7 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, ret = io_sqe_files_unregister(ctx); break; case IORING_REGISTER_FILES_UPDATE: - ret = io_sqe_files_update(ctx, arg, nr_args); + ret = io_register_files_update(ctx, arg, nr_args); break; case IORING_REGISTER_EVENTFD: case IORING_REGISTER_EVENTFD_ASYNC: @@ -9883,12 +10809,43 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, case IORING_REGISTER_RESTRICTIONS: ret = io_register_restrictions(ctx, arg, nr_args); break; + case IORING_REGISTER_FILES2: + ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE); + break; + case IORING_REGISTER_FILES_UPDATE2: + ret = io_register_rsrc_update(ctx, arg, nr_args, + IORING_RSRC_FILE); + break; + case IORING_REGISTER_BUFFERS2: + ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER); + break; + case IORING_REGISTER_BUFFERS_UPDATE: + ret = io_register_rsrc_update(ctx, arg, nr_args, + IORING_RSRC_BUFFER); + break; + case IORING_REGISTER_IOWQ_AFF: + ret = -EINVAL; + if (!arg || !nr_args) + break; + ret = io_register_iowq_aff(ctx, arg, nr_args); + break; + case IORING_UNREGISTER_IOWQ_AFF: + ret = -EINVAL; + if (arg || nr_args) + break; + ret = io_unregister_iowq_aff(ctx); + break; + case IORING_REGISTER_IOWQ_MAX_WORKERS: + ret = -EINVAL; + if (!arg || nr_args != 2) + break; + ret = io_register_iowq_max_workers(ctx, arg); + break; default: ret = -EINVAL; break; }

-out: if (io_register_op_must_quiesce(opcode)) { /* bring the ctx back to life */ percpu_ref_reinit(&ctx->refs); @@ -9914,6 +10871,8 @@ SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,

ctx = f.file->private_data;

+ io_run_task_work(); + mutex_lock(&ctx->uring_lock); ret = __io_uring_register(ctx, opcode, arg, nr_args); mutex_unlock(&ctx->uring_lock); @@ -9960,12 +10919,27 @@ static int __init io_uring_init(void) BUILD_BUG_SQE_ELEM(28, __u32, splice_flags); BUILD_BUG_SQE_ELEM(32, __u64, user_data); BUILD_BUG_SQE_ELEM(40, __u16, buf_index); + BUILD_BUG_SQE_ELEM(40, __u16, buf_group); BUILD_BUG_SQE_ELEM(42, __u16, personality); BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in); + BUILD_BUG_SQE_ELEM(44, __u32, file_index); + + BUILD_BUG_ON(sizeof(struct io_uring_files_update) != + sizeof(struct io_uring_rsrc_update)); + BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) > + sizeof(struct io_uring_rsrc_update2)); + + /* ->buf_index is u16 */ + BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16)); + + /* should fit into one byte */ + BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8));

BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST); - BUILD_BUG_ON(__REQ_F_LAST_BIT >= 8 * sizeof(int)); - req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC); + BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int)); + + req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC | + SLAB_ACCOUNT); return 0; }; __initcall(io_uring_init); diff --git a/kernel/exit.c b/kernel/exit.c index d612cb5b5943..26a81ea63156 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -764,7 +764,7 @@ void __noreturn do_exit(long code) schedule(); }

- io_uring_files_cancel(tsk->files); + io_uring_files_cancel(); exit_signals(tsk); /* sets PF_EXITING */

/* sync mm's RSS info before statistics gathering */ diff --git a/kernel/fork.c b/kernel/fork.c index 6e836b048662..0e141623a95d 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -950,6 +950,7 @@ static struct task_struct *dup_task_struct(struct task_struct *orig, int node) tsk->splice_pipe = NULL; tsk->task_frag.page = NULL; tsk->wake_q.next = NULL; + tsk->pf_io_worker = NULL;

account_kernel_stack(tsk, 1);

diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 62d14fba4ca6..a2ea3b0ab334 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -21,7 +21,7 @@ #include <asm/tlb.h>

#include "../workqueue_internal.h" -#include "../../fs/io-wq.h" +#include "../../io_uring/io-wq.h" #include "../smpboot.h"

#include "pelt.h"

From: Guo Xuenan guoxuenan@huawei.com

Offering: HULK hulk inclusion category: bugfix bugzilla: 186692,https://gitee.com/openeuler/kernel/issues/I5930C

-------------------

when set up sq ring size with IORING_MAX_ENTRIES, io_submit_sqes may looping ~32768 times which may trigger soft lockups. add cond_resched condition to avoid this bad situation.

set sq ring size 32768 to perform stress test as follows:

watchdog: BUG: soft lockup - CPU#3 stuck for 26s! [poc:691] Modules linked in: CPU: 3 PID: 691 Comm: poc Not tainted 5.18.0+ #9 Hardware name: linux,dummy-virt (DT) pstate: 60000005 (nZCv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : arch_local_irq_enable+0xc/0x28 lr : io_issue_sqe+0x870/0x28e8 sp : ffff80000e0f7800 x29: ffff80000e0f7800 x28: ffff0000cf850dd0 x27: ffff0000cf2c2000 x26: ffff8000096f4b20 x25: ffff0000cd769c00 x24: ffff0000c12b6650 x23: ffff800009dad958 x22: 00000006fc23ac00 x21: ffff0000cd769c08 x20: 1ffff00001c1ef1a x19: ffff0000cd767e00 x18: 0000000000000000 x17: ffff800008032b74 x16: ffff800008636448 x15: 0000fffff7166568 x14: ffff80000861edf0 x13: ffff600019e58449 x12: 1fffe00019e58448 x11: 1fffe00019e58448 x10: ffff600019e58448 x9 : dfff800000000000 x8 : ffff0000cf2c2244 x7 : 0000000000000001 x6 : ffff600019e58449 x5 : ffff600019e58449 x4 : ffff600019e58449 x3 : ffff8000086306c0 x2 : 0000000000000001 x1 : ffff0000cf2c2244 x0 : 00000000000000e0 Call trace: arch_local_irq_enable+0xc/0x28 io_submit_sqes+0x530/0x29d8 __arm64_sys_io_uring_enter+0x380/0xd18 invoke_syscall+0x64/0x180 el0_svc_common.constprop.2+0x178/0x208 do_el0_svc+0x84/0xa0 el0_svc+0x48/0x1a0 el0t_64_sync_handler+0x90/0xb8 el0t_64_sync+0x180/0x184 Kernel panic - not syncing: softlockup: hung tasks CPU: 3 PID: 691 Comm: poc Tainted: G L 5.18.0+ #9 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0x218/0x228 show_stack+0x20/0x68 dump_stack_lvl+0x68/0x84 dump_stack+0x1c/0x38 panic+0x1ec/0x3ec watchdog_timer_fn+0x28c/0x300 __hrtimer_run_queues+0x1d8/0x498 hrtimer_interrupt+0x238/0x558 arch_timer_handler_virt+0x48/0x60 handle_percpu_devid_irq+0xdc/0x270 generic_handle_domain_irq+0x50/0x70 gic_handle_irq+0x8c/0x4bc call_on_irq_stack+0x2c/0x38 do_interrupt_handler+0xc4/0xc8 el1_interrupt+0x48/0xb0 el1h_64_irq_handler+0x18/0x28 el1h_64_irq+0x74/0x78 arch_local_irq_enable+0xc/0x28 io_submit_sqes+0x530/0x29d8 __arm64_sys_io_uring_enter+0x380/0xd18 invoke_syscall+0x64/0x180 el0_svc_common.constprop.2+0x178/0x208 do_el0_svc+0x84/0xa0 el0_svc+0x48/0x1a0 el0t_64_sync_handler+0x90/0xb8 el0t_64_sync+0x180/0x184 SMP: stopping secondary CPUs Kernel Offset: disabled CPU features: 0x110,00008f09,00001006 Memory Limit: none ---[ end Kernel panic - not syncing: softlockup: hung tasks ]---

Link: https://lore.kernel.org/all/d4bc3afb-02d5-1793-cffa-e15b2bdb0028@huawei.com/ Signed-off-by: Guo Xuenan guoxuenan@huawei.com

Conflict: io_uring/io_uring.c

Signed-off-by: Li Lingfeng lilingfeng3@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- io_uring/io_uring.c | 4 ++++ 1 file changed, 4 insertions(+)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index a200750b536c..315031bb38e2 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -7190,6 +7190,10 @@ static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr) submitted++; if (io_submit_sqe(ctx, req, sqe)) break; + + /* to avoid doing too much in one submit round */ + if (submitted > IORING_MAX_ENTRIES / 2) + cond_resched(); }

if (unlikely(submitted != nr)) {

From: Sergey Shtylyov s.shtylyov@omp.ru

stable inclusion from stable-v5.10.150 commit 904f881b57360cf85de962d84d8614d94431f60e category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I6D0XA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

--------------------------------

cpufreq_get_hw_max_freq() returns max frequency in kHz as *unsigned int*, while freq_inv_set_max_ratio() gets passed this frequency in Hz as 'u64'. Multiplying max frequency by 1000 can potentially result in overflow -- multiplying by 1000ULL instead should avoid that...

Found by Linux Verification Center (linuxtesting.org) with the SVACE static analysis tool.

Fixes: cd0ed03a8903 ("arm64: use activity monitors for frequency invariance") Signed-off-by: Sergey Shtylyov s.shtylyov@omp.ru Link: https://lore.kernel.org/r/01493d64-2bce-d968-86dc-11a122a9c07d@omp.ru Signed-off-by: Will Deacon will@kernel.org

conflicts: arch/arm64/kernel/topology.c

Signed-off-by: Lin Yujun linyujun809@huawei.com Reviewed-by: Zhang Jianhua chris.zjh@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- arch/arm64/kernel/topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/topology.c b/arch/arm64/kernel/topology.c index 3084a81250fe..0c9f986e3c6b 100644 --- a/arch/arm64/kernel/topology.c +++ b/arch/arm64/kernel/topology.c @@ -252,7 +252,7 @@ static int __init init_amu_fie(void) for_each_present_cpu(cpu) { if (!freq_counters_valid(cpu) || freq_inv_set_max_ratio(cpu, - cpufreq_get_hw_max_freq(cpu) * 1000, + cpufreq_get_hw_max_freq(cpu) * 1000ULL, arch_timer_get_rate())) continue;

From: Li Nan linan122@huawei.com

hulk inclusion category: bugfix bugzilla: 188284, https://gitee.com/openeuler/kernel/issues/I6ECB2 CVE: NA

--------------------------------

There is no input check when echo md/safe_mode_delay, and overflow will occur. There is risk of overflow in strict_strtoul_scaled(), too. Fixed it by using kstrtoul instead of parsing word one by one.

Signed-off-by: Li Nan linan122@huawei.com Reviewed-by: Hou Tao houtao1@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- drivers/md/md.c | 66 ++++++++++++++++++++++++++++++++----------------- 1 file changed, 43 insertions(+), 23 deletions(-)

diff --git a/drivers/md/md.c b/drivers/md/md.c index 8658e3df3b24..1af74721e67c 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -3846,35 +3846,51 @@ static int analyze_sbs(struct mddev *mddev) */ int strict_strtoul_scaled(const char *cp, unsigned long *res, int scale) { - unsigned long result = 0; - long decimals = -1; - while (isdigit(*cp) || (*cp == '.' && decimals < 0)) { - if (*cp == '.') - decimals = 0; - else if (decimals < scale) { - unsigned int value; - value = *cp - '0'; - result = result * 10 + value; - if (decimals >= 0) - decimals++; - } - cp++; - } - if (*cp == '\n') - cp++; - if (*cp) + unsigned long result = 0, decimals = 0; + char *pos, *str; + int rv; + + str = kmemdup_nul(cp, strlen(cp), GFP_KERNEL); + if (!str) + return -ENOMEM; + pos = strchr(str, '.'); + if (pos) { + int cnt = scale; + + *pos = '\0'; + while (isdigit(*(++pos))) { + if (cnt) { + decimals = decimals * 10 + *pos - '0'; + cnt--; + } + } + if (*pos == '\n') + pos++; + if (*pos) { + kfree(str); + return -EINVAL; + } + decimals *= int_pow(10, cnt); + } + + rv = kstrtoul(str, 10, &result); + kfree(str); + if (rv) + return rv; + + if (result > (ULONG_MAX - decimals) / (unsigned int)int_pow(10, scale)) return -EINVAL; - if (decimals < 0) - decimals = 0; - *res = result * int_pow(10, scale - decimals); - return 0; + *res = result * int_pow(10, scale) + decimals; + + return rv; }

static ssize_t safe_delay_show(struct mddev *mddev, char *page) { - int msec = (mddev->safemode_delay*1000)/HZ; - return sprintf(page, "%d.%03d\n", msec/1000, msec%1000); + unsigned int msec = ((unsigned long)mddev->safemode_delay*1000)/HZ; + + return sprintf(page, "%u.%03u\n", msec/1000, msec%1000); } static ssize_t safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len) @@ -3888,10 +3904,14 @@ safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len)

if (strict_strtoul_scaled(cbuf, &msec, 3) < 0) return -EINVAL; + if (msec > UINT_MAX) + return -EINVAL; + if (msec == 0) mddev->safemode_delay = 0; else { unsigned long old_delay = mddev->safemode_delay; + /* HZ <= 1000, so new_delay < UINT_MAX, too */ unsigned long new_delay = (msec*HZ)/1000;

if (new_delay == 0)

From: Zhong Jinghua zhongjinghua@huawei.com

Offering: HULK hulk inclusion category: bugfix bugzilla: 188413, https://gitee.com/openeuler/kernel/issues/I6GWYG

----------------------------------------

A panic error is like below:

nbd_genl_connect nbd_dev_add first_minor = index << part_shift; // index =-1 ... __device_add_disk blk_alloc_devt *devt = MKDEV(disk->major, disk->first_minor + part->partno); // part->partno = 0， first_minor = 11...110000 major is covered

There, index < 0 will reassign an index, but here disk->first_minor is assigned -1 << part_shift.

This causes to the creation of the device with the same major and minor device numbers each time the incoming index<0, and this will lead to creation of kobject failed: Warning: kobject_add_internal failed for 4095:1048544 with -EEXIST, don't try to register things with the same name in the same directory.

Fix it by moving the first_minor assignment down to after getting the new index.

Fixes: 60141517d289 ("nbd: Fix use-after-free in blk_mq_free_rqs") Signed-off-by: Zhong Jinghua zhongjinghua@huawei.com Reviewed-by: Yu Kuai yukuai3@huawei.com Reviewed-by: Hou Tao houtao1@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- drivers/block/nbd.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index ebcdb6025be3..b1ebd503eb5d 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -1771,7 +1771,6 @@ static int nbd_dev_add(int index) struct gendisk *disk; struct request_queue *q; int err = -ENOMEM; - int first_minor = index << part_shift;

nbd = kzalloc(sizeof(struct nbd_device), GFP_KERNEL); if (!nbd) @@ -1835,7 +1834,7 @@ static int nbd_dev_add(int index) refcount_set(&nbd->refs, 1); INIT_LIST_HEAD(&nbd->list); disk->major = NBD_MAJOR; - disk->first_minor = first_minor; + disk->first_minor = index << part_shift; disk->fops = &nbd_fops; disk->private_data = nbd; sprintf(disk->disk_name, "nbd%d", index);

From: Eric Dumazet edumazet@google.com

stable inclusion from stable-v5.10.166 commit cf9a2ce0383e2cb182d223d2ece17f964432367e category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I6H5DD CVE: NA

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

--------------------------------

[ Upstream commit ea4fdbaa2f7798cb25adbe4fd52ffc6356f097bb ]

As reported by syzbot and hinted by Vinicius, I should not have added a qdisc_synchronize() call in taprio_reset()

taprio_reset() can be called with qdisc spinlock held (and BH disabled) as shown in included syzbot report [1].

Only taprio_destroy() needed this synchronization, as explained in the blamed commit changelog.

[1]

BUG: scheduling while atomic: syz-executor150/5091/0x00000202 2 locks held by syz-executor150/5091: Modules linked in: Preemption disabled at: [<0000000000000000>] 0x0 Kernel panic - not syncing: scheduling while atomic: panic_on_warn set ... CPU: 1 PID: 5091 Comm: syz-executor150 Not tainted 6.2.0-rc3-syzkaller-00219-g010a74f52203 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106 panic+0x2cc/0x626 kernel/panic.c:318 check_panic_on_warn.cold+0x19/0x35 kernel/panic.c:238 __schedule_bug.cold+0xd5/0xfe kernel/sched/core.c:5836 schedule_debug kernel/sched/core.c:5865 [inline] __schedule+0x34e4/0x5450 kernel/sched/core.c:6500 schedule+0xde/0x1b0 kernel/sched/core.c:6682 schedule_timeout+0x14e/0x2a0 kernel/time/timer.c:2167 schedule_timeout_uninterruptible kernel/time/timer.c:2201 [inline] msleep+0xb6/0x100 kernel/time/timer.c:2322 qdisc_synchronize include/net/sch_generic.h:1295 [inline] taprio_reset+0x93/0x270 net/sched/sch_taprio.c:1703 qdisc_reset+0x10c/0x770 net/sched/sch_generic.c:1022 dev_reset_queue+0x92/0x130 net/sched/sch_generic.c:1285 netdev_for_each_tx_queue include/linux/netdevice.h:2464 [inline] dev_deactivate_many+0x36d/0x9f0 net/sched/sch_generic.c:1351 dev_deactivate+0xed/0x1b0 net/sched/sch_generic.c:1374 qdisc_graft+0xe4a/0x1380 net/sched/sch_api.c:1080 tc_modify_qdisc+0xb6b/0x19a0 net/sched/sch_api.c:1689 rtnetlink_rcv_msg+0x43e/0xca0 net/core/rtnetlink.c:6141 netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2564 netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline] netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1356 netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1932 sock_sendmsg_nosec net/socket.c:714 [inline] sock_sendmsg+0xd3/0x120 net/socket.c:734 ____sys_sendmsg+0x712/0x8c0 net/socket.c:2476 ___sys_sendmsg+0x110/0x1b0 net/socket.c:2530 __sys_sendmsg+0xf7/0x1c0 net/socket.c:2559 do_syscall_x64 arch/x86/entry/common.c:50 [inline]

Fixes: 3a415d59c1db ("net/sched: sch_taprio: fix possible use-after-free") Link: https://lore.kernel.org/netdev/167387581653.2747.13878941339893288655.git-pa... Reported-by: syzbot syzkaller@googlegroups.com Signed-off-by: Eric Dumazet edumazet@google.com Cc: Vinicius Costa Gomes vinicius.gomes@intel.com Link: https://lore.kernel.org/r/20230123084552.574396-1-edumazet@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zhengchao Shao shaozhengchao@huawei.com Reviewed-by: Yue Haibing yuehaibing@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- net/sched/sch_taprio.c | 1 - 1 file changed, 1 deletion(-)

diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c index 696dc9b96272..abef2e4d6000 100644 --- a/net/sched/sch_taprio.c +++ b/net/sched/sch_taprio.c @@ -1621,7 +1621,6 @@ static void taprio_reset(struct Qdisc *sch) int i;

hrtimer_cancel(&q->advance_timer); - qdisc_synchronize(sch);

if (q->qdiscs) { for (i = 0; i < dev->num_tx_queues; i++)

From: Todd Kjos tkjos@google.com

stable inclusion from stable-v5.10.157 commit 23e9d815fad84c1bee3742a8de4bd39510435362 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6DKVG CVE: CVE-2023-20938

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

--------------------------------

commit 6d98eb95b450a75adb4516a1d33652dc78d2b20c upstream.

Transactions are copied from the sender to the target first and objects like BINDER_TYPE_PTR and BINDER_TYPE_FDA are then fixed up. This means there is a short period where the sender's version of these objects are visible to the target prior to the fixups.

Instead of copying all of the data first, copy data only after any needed fixups have been applied.

Fixes: 457b9a6f09f0 ("Staging: android: add binder driver") Reviewed-by: Martijn Coenen maco@android.com Acked-by: Christian Brauner christian.brauner@ubuntu.com Signed-off-by: Todd Kjos tkjos@google.com Link: https://lore.kernel.org/r/20211130185152.437403-3-tkjos@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org [cmllamas: fix trivial merge conflict] Signed-off-by: Carlos Llamas cmllamas@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Huafei lihuafei1@huawei.com Reviewed-by: Zheng Yejian zhengyejian1@huawei.com Reviewed-by: Xiu Jianfeng xiujianfeng@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- drivers/android/binder.c | 94 ++++++++++++++++++++++++++++++---------- 1 file changed, 70 insertions(+), 24 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c index a867fd47ac46..c3e3ef6a1888 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -2008,15 +2008,21 @@ static void binder_cleanup_transaction(struct binder_transaction *t, /** * binder_get_object() - gets object and checks for valid metadata * @proc: binder_proc owning the buffer + * @u: sender's user pointer to base of buffer * @buffer: binder_buffer that we're parsing. * @offset: offset in the @buffer at which to validate an object. * @object: struct binder_object to read into * - * Return: If there's a valid metadata object at @offset in @buffer, the + * Copy the binder object at the given offset into @object. If @u is + * provided then the copy is from the sender's buffer. If not, then + * it is copied from the target's @buffer. + * + * Return: If there's a valid metadata object at @offset, the * size of that object. Otherwise, it returns zero. The object * is read into the struct binder_object pointed to by @object. */ static size_t binder_get_object(struct binder_proc *proc, + const void __user *u, struct binder_buffer *buffer, unsigned long offset, struct binder_object *object) @@ -2026,10 +2032,16 @@ static size_t binder_get_object(struct binder_proc *proc, size_t object_size = 0;

read_size = min_t(size_t, sizeof(*object), buffer->data_size - offset); - if (offset > buffer->data_size || read_size < sizeof(*hdr) || - binder_alloc_copy_from_buffer(&proc->alloc, object, buffer, - offset, read_size)) + if (offset > buffer->data_size || read_size < sizeof(*hdr)) return 0; + if (u) { + if (copy_from_user(object, u + offset, read_size)) + return 0; + } else { + if (binder_alloc_copy_from_buffer(&proc->alloc, object, buffer, + offset, read_size)) + return 0; + }

/* Ok, now see if we read a complete object. */ hdr = &object->hdr; @@ -2102,7 +2114,7 @@ static struct binder_buffer_object *binder_validate_ptr( b, buffer_offset, sizeof(object_offset))) return NULL; - object_size = binder_get_object(proc, b, object_offset, object); + object_size = binder_get_object(proc, NULL, b, object_offset, object); if (!object_size || object->hdr.type != BINDER_TYPE_PTR) return NULL; if (object_offsetp) @@ -2167,7 +2179,8 @@ static bool binder_validate_fixup(struct binder_proc *proc, unsigned long buffer_offset; struct binder_object last_object; struct binder_buffer_object *last_bbo; - size_t object_size = binder_get_object(proc, b, last_obj_offset, + size_t object_size = binder_get_object(proc, NULL, b, + last_obj_offset, &last_object); if (object_size != sizeof(*last_bbo)) return false; @@ -2282,7 +2295,7 @@ static void binder_transaction_buffer_release(struct binder_proc *proc, if (!binder_alloc_copy_from_buffer(&proc->alloc, &object_offset, buffer, buffer_offset, sizeof(object_offset))) - object_size = binder_get_object(proc, buffer, + object_size = binder_get_object(proc, NULL, buffer, object_offset, &object); if (object_size == 0) { pr_err("transaction release %d bad object at offset %lld, size %zd\n", @@ -2848,6 +2861,7 @@ static void binder_transaction(struct binder_proc *proc, binder_size_t off_start_offset, off_end_offset; binder_size_t off_min; binder_size_t sg_buf_offset, sg_buf_end_offset; + binder_size_t user_offset = 0; struct binder_proc *target_proc = NULL; struct binder_thread *target_thread = NULL; struct binder_node *target_node = NULL; @@ -2862,6 +2876,8 @@ static void binder_transaction(struct binder_proc *proc, int t_debug_id = atomic_inc_return(&binder_last_id); char *secctx = NULL; u32 secctx_sz = 0; + const void __user *user_buffer = (const void __user *) + (uintptr_t)tr->data.ptr.buffer;

e = binder_transaction_log_add(&binder_transaction_log); e->debug_id = t_debug_id; @@ -3173,19 +3189,6 @@ static void binder_transaction(struct binder_proc *proc, t->buffer->clear_on_free = !!(t->flags & TF_CLEAR_BUF); trace_binder_transaction_alloc_buf(t->buffer);

- if (binder_alloc_copy_user_to_buffer( - &target_proc->alloc, - t->buffer, 0, - (const void __user *) - (uintptr_t)tr->data.ptr.buffer, - tr->data_size)) { - binder_user_error("%d:%d got transaction with invalid data ptr\n", - proc->pid, thread->pid); - return_error = BR_FAILED_REPLY; - return_error_param = -EFAULT; - return_error_line = __LINE__; - goto err_copy_data_failed; - } if (binder_alloc_copy_user_to_buffer( &target_proc->alloc, t->buffer, @@ -3230,6 +3233,7 @@ static void binder_transaction(struct binder_proc *proc, size_t object_size; struct binder_object object; binder_size_t object_offset; + binder_size_t copy_size;

if (binder_alloc_copy_from_buffer(&target_proc->alloc, &object_offset, @@ -3241,8 +3245,27 @@ static void binder_transaction(struct binder_proc *proc, return_error_line = __LINE__; goto err_bad_offset; } - object_size = binder_get_object(target_proc, t->buffer, - object_offset, &object); + + /* + * Copy the source user buffer up to the next object + * that will be processed. + */ + copy_size = object_offset - user_offset; + if (copy_size && (user_offset > object_offset || + binder_alloc_copy_user_to_buffer( + &target_proc->alloc, + t->buffer, user_offset, + user_buffer + user_offset, + copy_size))) { + binder_user_error("%d:%d got transaction with invalid data ptr\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EFAULT; + return_error_line = __LINE__; + goto err_copy_data_failed; + } + object_size = binder_get_object(target_proc, user_buffer, + t->buffer, object_offset, &object); if (object_size == 0 || object_offset < off_min) { binder_user_error("%d:%d got transaction with invalid offset (%lld, min %lld max %lld) or object.\n", proc->pid, thread->pid, @@ -3254,6 +3277,11 @@ static void binder_transaction(struct binder_proc *proc, return_error_line = __LINE__; goto err_bad_offset; } + /* + * Set offset to the next buffer fragment to be + * copied + */ + user_offset = object_offset + object_size;

hdr = &object.hdr; off_min = object_offset + object_size; @@ -3349,9 +3377,14 @@ static void binder_transaction(struct binder_proc *proc, } ret = binder_translate_fd_array(fda, parent, t, thread, in_reply_to); - if (ret < 0) { + if (!ret) + ret = binder_alloc_copy_to_buffer(&target_proc->alloc, + t->buffer, + object_offset, + fda, sizeof(*fda)); + if (ret) { return_error = BR_FAILED_REPLY; - return_error_param = ret; + return_error_param = ret > 0 ? -EINVAL : ret; return_error_line = __LINE__; goto err_translate_failed; } @@ -3421,6 +3454,19 @@ static void binder_transaction(struct binder_proc *proc, goto err_bad_object_type; } } + /* Done processing objects, copy the rest of the buffer */ + if (binder_alloc_copy_user_to_buffer( + &target_proc->alloc, + t->buffer, user_offset, + user_buffer + user_offset, + tr->data_size - user_offset)) { + binder_user_error("%d:%d got transaction with invalid data ptr\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = -EFAULT; + return_error_line = __LINE__; + goto err_copy_data_failed; + } tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE; t->work.type = BINDER_WORK_TRANSACTION;

From: Todd Kjos tkjos@google.com

stable inclusion from stable-v5.10.157 commit c9d3f25a7f4e3aab3dfd91885e3d428bccdcb0e1 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6DKVG CVE: CVE-2023-20938

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

--------------------------------

commit 09184ae9b5756cc469db6fd1d1cfdcffbf627c2d upstream.

BINDER_TYPE_PTR objects point to memory areas in the source process to be copied into the target buffer as part of a transaction. This implements a scatter- gather model where non-contiguous memory in a source process is "gathered" into a contiguous region in the target buffer.

The data can include pointers that must be fixed up to correctly point to the copied data. To avoid making source process pointers visible to the target process, this patch defers the copy until the fixups are known and then copies and fixeups are done together.

There is a special case of BINDER_TYPE_FDA which applies the fixup later in the target process context. In this case the user data is skipped (so no untranslated fds become visible to the target).

Reviewed-by: Martijn Coenen maco@android.com Signed-off-by: Todd Kjos tkjos@google.com Link: https://lore.kernel.org/r/20211130185152.437403-5-tkjos@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org [cmllamas: fix trivial merge conflict] Signed-off-by: Carlos Llamas cmllamas@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Huafei lihuafei1@huawei.com Reviewed-by: Zheng Yejian zhengyejian1@huawei.com Reviewed-by: Xiu Jianfeng xiujianfeng@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- drivers/android/binder.c | 299 +++++++++++++++++++++++++++++++++++---- 1 file changed, 274 insertions(+), 25 deletions(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 772be91c3949..288ffdff9bbf 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -2633,7 +2633,246 @@ static int binder_translate_fd(u32 fd, binder_size_t fd_offset, return ret; }

-static int binder_translate_fd_array(struct binder_fd_array_object *fda, +/** + * struct binder_ptr_fixup - data to be fixed-up in target buffer + * @offset offset in target buffer to fixup + * @skip_size bytes to skip in copy (fixup will be written later) + * @fixup_data data to write at fixup offset + * @node list node + * + * This is used for the pointer fixup list (pf) which is created and consumed + * during binder_transaction() and is only accessed locally. No + * locking is necessary. + * + * The list is ordered by @offset. + */ +struct binder_ptr_fixup { + binder_size_t offset; + size_t skip_size; + binder_uintptr_t fixup_data; + struct list_head node; +}; + +/** + * struct binder_sg_copy - scatter-gather data to be copied + * @offset offset in target buffer + * @sender_uaddr user address in source buffer + * @length bytes to copy + * @node list node + * + * This is used for the sg copy list (sgc) which is created and consumed + * during binder_transaction() and is only accessed locally. No + * locking is necessary. + * + * The list is ordered by @offset. + */ +struct binder_sg_copy { + binder_size_t offset; + const void __user *sender_uaddr; + size_t length; + struct list_head node; +}; + +/** + * binder_do_deferred_txn_copies() - copy and fixup scatter-gather data + * @alloc: binder_alloc associated with @buffer + * @buffer: binder buffer in target process + * @sgc_head: list_head of scatter-gather copy list + * @pf_head: list_head of pointer fixup list + * + * Processes all elements of @sgc_head, applying fixups from @pf_head + * and copying the scatter-gather data from the source process' user + * buffer to the target's buffer. It is expected that the list creation + * and processing all occurs during binder_transaction() so these lists + * are only accessed in local context. + * + * Return: 0=success, else -errno + */ +static int binder_do_deferred_txn_copies(struct binder_alloc *alloc, + struct binder_buffer *buffer, + struct list_head *sgc_head, + struct list_head *pf_head) +{ + int ret = 0; + struct binder_sg_copy *sgc, *tmpsgc; + struct binder_ptr_fixup *pf = + list_first_entry_or_null(pf_head, struct binder_ptr_fixup, + node); + + list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) { + size_t bytes_copied = 0; + + while (bytes_copied < sgc->length) { + size_t copy_size; + size_t bytes_left = sgc->length - bytes_copied; + size_t offset = sgc->offset + bytes_copied; + + /* + * We copy up to the fixup (pointed to by pf) + */ + copy_size = pf ? min(bytes_left, (size_t)pf->offset - offset) + : bytes_left; + if (!ret && copy_size) + ret = binder_alloc_copy_user_to_buffer( + alloc, buffer, + offset, + sgc->sender_uaddr + bytes_copied, + copy_size); + bytes_copied += copy_size; + if (copy_size != bytes_left) { + BUG_ON(!pf); + /* we stopped at a fixup offset */ + if (pf->skip_size) { + /* + * we are just skipping. This is for + * BINDER_TYPE_FDA where the translated + * fds will be fixed up when we get + * to target context. + */ + bytes_copied += pf->skip_size; + } else { + /* apply the fixup indicated by pf */ + if (!ret) + ret = binder_alloc_copy_to_buffer( + alloc, buffer, + pf->offset, + &pf->fixup_data, + sizeof(pf->fixup_data)); + bytes_copied += sizeof(pf->fixup_data); + } + list_del(&pf->node); + kfree(pf); + pf = list_first_entry_or_null(pf_head, + struct binder_ptr_fixup, node); + } + } + list_del(&sgc->node); + kfree(sgc); + } + BUG_ON(!list_empty(pf_head)); + BUG_ON(!list_empty(sgc_head)); + + return ret > 0 ? -EINVAL : ret; +} + +/** + * binder_cleanup_deferred_txn_lists() - free specified lists + * @sgc_head: list_head of scatter-gather copy list + * @pf_head: list_head of pointer fixup list + * + * Called to clean up @sgc_head and @pf_head if there is an + * error. + */ +static void binder_cleanup_deferred_txn_lists(struct list_head *sgc_head, + struct list_head *pf_head) +{ + struct binder_sg_copy *sgc, *tmpsgc; + struct binder_ptr_fixup *pf, *tmppf; + + list_for_each_entry_safe(sgc, tmpsgc, sgc_head, node) { + list_del(&sgc->node); + kfree(sgc); + } + list_for_each_entry_safe(pf, tmppf, pf_head, node) { + list_del(&pf->node); + kfree(pf); + } +} + +/** + * binder_defer_copy() - queue a scatter-gather buffer for copy + * @sgc_head: list_head of scatter-gather copy list + * @offset: binder buffer offset in target process + * @sender_uaddr: user address in source process + * @length: bytes to copy + * + * Specify a scatter-gather block to be copied. The actual copy must + * be deferred until all the needed fixups are identified and queued. + * Then the copy and fixups are done together so un-translated values + * from the source are never visible in the target buffer. + * + * We are guaranteed that repeated calls to this function will have + * monotonically increasing @offset values so the list will naturally + * be ordered. + * + * Return: 0=success, else -errno + */ +static int binder_defer_copy(struct list_head *sgc_head, binder_size_t offset, + const void __user *sender_uaddr, size_t length) +{ + struct binder_sg_copy *bc = kzalloc(sizeof(*bc), GFP_KERNEL); + + if (!bc) + return -ENOMEM; + + bc->offset = offset; + bc->sender_uaddr = sender_uaddr; + bc->length = length; + INIT_LIST_HEAD(&bc->node); + + /* + * We are guaranteed that the deferred copies are in-order + * so just add to the tail. + */ + list_add_tail(&bc->node, sgc_head); + + return 0; +} + +/** + * binder_add_fixup() - queue a fixup to be applied to sg copy + * @pf_head: list_head of binder ptr fixup list + * @offset: binder buffer offset in target process + * @fixup: bytes to be copied for fixup + * @skip_size: bytes to skip when copying (fixup will be applied later) + * + * Add the specified fixup to a list ordered by @offset. When copying + * the scatter-gather buffers, the fixup will be copied instead of + * data from the source buffer. For BINDER_TYPE_FDA fixups, the fixup + * will be applied later (in target process context), so we just skip + * the bytes specified by @skip_size. If @skip_size is 0, we copy the + * value in @fixup. + * + * This function is called *mostly* in @offset order, but there are + * exceptions. Since out-of-order inserts are relatively uncommon, + * we insert the new element by searching backward from the tail of + * the list. + * + * Return: 0=success, else -errno + */ +static int binder_add_fixup(struct list_head *pf_head, binder_size_t offset, + binder_uintptr_t fixup, size_t skip_size) +{ + struct binder_ptr_fixup *pf = kzalloc(sizeof(*pf), GFP_KERNEL); + struct binder_ptr_fixup *tmppf; + + if (!pf) + return -ENOMEM; + + pf->offset = offset; + pf->fixup_data = fixup; + pf->skip_size = skip_size; + INIT_LIST_HEAD(&pf->node); + + /* Fixups are *mostly* added in-order, but there are some + * exceptions. Look backwards through list for insertion point. + */ + list_for_each_entry_reverse(tmppf, pf_head, node) { + if (tmppf->offset < pf->offset) { + list_add(&pf->node, &tmppf->node); + return 0; + } + } + /* + * if we get here, then the new offset is the lowest so + * insert at the head + */ + list_add(&pf->node, pf_head); + return 0; +} + +static int binder_translate_fd_array(struct list_head *pf_head, + struct binder_fd_array_object *fda, const void __user *sender_ubuffer, struct binder_buffer_object *parent, struct binder_buffer_object *sender_uparent, @@ -2645,6 +2884,7 @@ static int binder_translate_fd_array(struct binder_fd_array_object *fda, binder_size_t fda_offset; const void __user *sender_ufda_base; struct binder_proc *proc = thread->proc; + int ret;

fd_buf_size = sizeof(u32) * fda->num_fds; if (fda->num_fds >= SIZE_MAX / sizeof(u32)) { @@ -2676,9 +2916,12 @@ static int binder_translate_fd_array(struct binder_fd_array_object *fda, proc->pid, thread->pid); return -EINVAL; } + ret = binder_add_fixup(pf_head, fda_offset, 0, fda->num_fds * sizeof(u32)); + if (ret) + return ret; + for (fdi = 0; fdi < fda->num_fds; fdi++) { u32 fd; - int ret; binder_size_t offset = fda_offset + fdi * sizeof(fd); binder_size_t sender_uoffset = fdi * sizeof(fd);

@@ -2692,7 +2935,8 @@ static int binder_translate_fd_array(struct binder_fd_array_object *fda, return 0; }

-static int binder_fixup_parent(struct binder_transaction *t, +static int binder_fixup_parent(struct list_head *pf_head, + struct binder_transaction *t, struct binder_thread *thread, struct binder_buffer_object *bp, binder_size_t off_start_offset, @@ -2738,14 +2982,7 @@ static int binder_fixup_parent(struct binder_transaction *t, } buffer_offset = bp->parent_offset + (uintptr_t)parent->buffer - (uintptr_t)b->user_data; - if (binder_alloc_copy_to_buffer(&target_proc->alloc, b, buffer_offset, - &bp->buffer, sizeof(bp->buffer))) { - binder_user_error("%d:%d got transaction with invalid parent offset\n", - proc->pid, thread->pid); - return -EINVAL; - } - - return 0; + return binder_add_fixup(pf_head, buffer_offset, bp->buffer, 0); }

/** @@ -2880,8 +3117,12 @@ static void binder_transaction(struct binder_proc *proc, int t_debug_id = atomic_inc_return(&binder_last_id); char *secctx = NULL; u32 secctx_sz = 0; + struct list_head sgc_head; + struct list_head pf_head; const void __user *user_buffer = (const void __user *) (uintptr_t)tr->data.ptr.buffer; + INIT_LIST_HEAD(&sgc_head); + INIT_LIST_HEAD(&pf_head);

e = binder_transaction_log_add(&binder_transaction_log); e->debug_id = t_debug_id; @@ -3398,8 +3639,8 @@ static void binder_transaction(struct binder_proc *proc, return_error_line = __LINE__; goto err_bad_parent; } - ret = binder_translate_fd_array(fda, user_buffer, - parent, + ret = binder_translate_fd_array(&pf_head, fda, + user_buffer, parent, &user_object.bbo, t, thread, in_reply_to); if (!ret) @@ -3431,19 +3672,14 @@ static void binder_transaction(struct binder_proc *proc, return_error_line = __LINE__; goto err_bad_offset; } - if (binder_alloc_copy_user_to_buffer( - &target_proc->alloc, - t->buffer, - sg_buf_offset, - (const void __user *) - (uintptr_t)bp->buffer, - bp->length)) { - binder_user_error("%d:%d got transaction with invalid offsets ptr\n", - proc->pid, thread->pid); - return_error_param = -EFAULT; + ret = binder_defer_copy(&sgc_head, sg_buf_offset, + (const void __user *)(uintptr_t)bp->buffer, + bp->length); + if (ret) { return_error = BR_FAILED_REPLY; + return_error_param = ret; return_error_line = __LINE__; - goto err_copy_data_failed; + goto err_translate_failed; } /* Fixup buffer pointer to target proc address space */ bp->buffer = (uintptr_t) @@ -3452,7 +3688,8 @@ static void binder_transaction(struct binder_proc *proc,

num_valid = (buffer_offset - off_start_offset) / sizeof(binder_size_t); - ret = binder_fixup_parent(t, thread, bp, + ret = binder_fixup_parent(&pf_head, t, + thread, bp, off_start_offset, num_valid, last_fixup_obj_off, @@ -3492,6 +3729,17 @@ static void binder_transaction(struct binder_proc *proc, return_error_line = __LINE__; goto err_copy_data_failed; } + + ret = binder_do_deferred_txn_copies(&target_proc->alloc, t->buffer, + &sgc_head, &pf_head); + if (ret) { + binder_user_error("%d:%d got transaction with invalid offsets ptr\n", + proc->pid, thread->pid); + return_error = BR_FAILED_REPLY; + return_error_param = ret; + return_error_line = __LINE__; + goto err_copy_data_failed; + } tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE; t->work.type = BINDER_WORK_TRANSACTION;

@@ -3558,6 +3806,7 @@ static void binder_transaction(struct binder_proc *proc, err_bad_offset: err_bad_parent: err_copy_data_failed: + binder_cleanup_deferred_txn_lists(&sgc_head, &pf_head); binder_free_txn_fixups(t); trace_binder_transaction_failed_buffer_release(t->buffer); binder_transaction_buffer_release(target_proc, NULL, t->buffer,

From: Alessandro Astone ales.astone@gmail.com

stable inclusion from stable-v5.10.157 commit 017de842533f4334d646f1d480f591f4ca9f5c7a category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6DKVG CVE: CVE-2023-20938

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

--------------------------------

commit 2d1746e3fda0c3612143d7c06f8e1d1830c13e23 upstream.

When handling BINDER_TYPE_FDA object we are pushing a parent fixup with a certain skip_size but no scatter-gather copy object, since the copy is handled standalone. If BINDER_TYPE_FDA is the last children the scatter-gather copy loop will never stop to skip it, thus we are left with an item in the parent fixup list. This will trigger the BUG_ON().

This is reproducible in android when playing a video. We receive a transaction that looks like this: obj[0] BINDER_TYPE_PTR, parent obj[1] BINDER_TYPE_PTR, child obj[2] BINDER_TYPE_PTR, child obj[3] BINDER_TYPE_FDA, child

Fixes: 09184ae9b575 ("binder: defer copies of pre-patched txn data") Acked-by: Todd Kjos tkjos@google.com Cc: stable stable@kernel.org Signed-off-by: Alessandro Astone ales.astone@gmail.com Link: https://lore.kernel.org/r/20220415120015.52684-2-ales.astone@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Carlos Llamas cmllamas@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Li Huafei lihuafei1@huawei.com Reviewed-by: Zheng Yejian zhengyejian1@huawei.com Reviewed-by: Xiu Jianfeng xiujianfeng@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- drivers/android/binder.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/android/binder.c b/drivers/android/binder.c index 80a0ba89c503..0fc6b3e2761a 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -2695,6 +2695,7 @@ static int binder_do_deferred_txn_copies(struct binder_alloc *alloc, { int ret = 0; struct binder_sg_copy *sgc, *tmpsgc; + struct binder_ptr_fixup *tmppf; struct binder_ptr_fixup *pf = list_first_entry_or_null(pf_head, struct binder_ptr_fixup, node); @@ -2749,7 +2750,11 @@ static int binder_do_deferred_txn_copies(struct binder_alloc *alloc, list_del(&sgc->node); kfree(sgc); } - BUG_ON(!list_empty(pf_head)); + list_for_each_entry_safe(pf, tmppf, pf_head, node) { + BUG_ON(pf->skip_size == 0); + list_del(&pf->node); + kfree(pf); + } BUG_ON(!list_empty(sgc_head));

return ret > 0 ? -EINVAL : ret;

From: Rodrigo Branco bsdaemon@google.com

stable inclusion from stable-v5.10.163 commit 67e39c4f4cb318cfbbf8982ab016c649ed97edaf category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6CU98 CVE: CVE-2023-0045

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

--------------------------------

commit a664ec9158eeddd75121d39c9a0758016097fa96 upstream.

We missed the window between the TIF flag update and the next reschedule.

Signed-off-by: Rodrigo Branco bsdaemon@google.com Reviewed-by: Borislav Petkov (AMD) bp@alien8.de Signed-off-by: Ingo Molnar mingo@kernel.org Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yuyao Lin linyuyao1@huawei.com Reviewed-by: Wang Weiyang wangweiyang2@huawei.com Reviewed-by: Wei Li liwei391@huawei.com Signed-off-by: Jialin Zhang zhangjialin11@huawei.com --- arch/x86/kernel/cpu/bugs.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 29ae372eb949..25f3fad210e0 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -1889,6 +1889,8 @@ static int ib_prctl_set(struct task_struct *task, unsigned long ctrl) if (ctrl == PR_SPEC_FORCE_DISABLE) task_set_spec_ib_force_disable(task); task_update_spec_tif(task); + if (task == current) + indirect_branch_prediction_barrier(); break; default: return -ERANGE;