From: Jens Axboe axboe@kernel.dk
mainline inclusion from mainline-5.6-rc1 commit c1ca757bd6f4632c510714631ddcc2d13030fe1e category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27 CVE: NA ---------------------------
This adds support for doing madvise(2) through io_uring. We assume that any operation can block, and hence punt everything async. This could be improved, but hard to make bullet proof. The async punt ensures it's safe.
Reviewed-by: Pavel Begunkov asml.silence@gmail.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: yangerkun yangerkun@huawei.com Reviewed-by: zhangyi (F) yi.zhang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- fs/io_uring.c | 59 +++++++++++++++++++++++++++++++++++ include/uapi/linux/io_uring.h | 1 + 2 files changed, 60 insertions(+)
diff --git a/fs/io_uring.c b/fs/io_uring.c index c47ab9ce390e..17bf101c270a 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -408,6 +408,13 @@ struct io_fadvise { u32 advice; };
+struct io_madvise { + struct file *file; + u64 addr; + u32 len; + u32 advice; +}; + struct io_async_connect { struct sockaddr_storage address; }; @@ -461,6 +468,7 @@ struct io_kiocb { struct io_close close; struct io_files_update files_update; struct io_fadvise fadvise; + struct io_madvise madvise; };
struct io_async_ctx *io; @@ -680,6 +688,10 @@ static const struct io_op_def io_op_defs[] = { /* IORING_OP_FADVISE */ .needs_file = 1, }, + { + /* IORING_OP_MADVISE */ + .needs_mm = 1, + }, };
static void io_wq_submit_work(struct io_wq_work **workptr); @@ -2446,6 +2458,42 @@ static int io_openat(struct io_kiocb *req, struct io_kiocb **nxt, return 0; }
+static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) +{ +#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU) + if (sqe->ioprio || sqe->buf_index || sqe->off) + return -EINVAL; + + req->madvise.addr = READ_ONCE(sqe->addr); + req->madvise.len = READ_ONCE(sqe->len); + req->madvise.advice = READ_ONCE(sqe->fadvise_advice); + return 0; +#else + return -EOPNOTSUPP; +#endif +} + +static int io_madvise(struct io_kiocb *req, struct io_kiocb **nxt, + bool force_nonblock) +{ +#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU) + struct io_madvise *ma = &req->madvise; + int ret; + + if (force_nonblock) + return -EAGAIN; + + ret = do_madvise(ma->addr, ma->len, ma->advice); + if (ret < 0) + req_set_fail_links(req); + io_cqring_add_event(req, ret); + io_put_req_find_next(req, nxt); + return 0; +#else + return -EOPNOTSUPP; +#endif +} + static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { if (sqe->ioprio || sqe->buf_index || sqe->addr) @@ -3763,6 +3811,9 @@ static int io_req_defer_prep(struct io_kiocb *req, case IORING_OP_FADVISE: ret = io_fadvise_prep(req, sqe); break; + case IORING_OP_MADVISE: + ret = io_madvise_prep(req, sqe); + break; default: printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n", req->opcode); @@ -3967,6 +4018,14 @@ static int io_issue_sqe(struct io_kiocb *req, const struct io_uring_sqe *sqe, } ret = io_fadvise(req, nxt, force_nonblock); break; + case IORING_OP_MADVISE: + if (sqe) { + ret = io_madvise_prep(req, sqe); + if (ret) + break; + } + ret = io_madvise(req, nxt, force_nonblock); + break; default: ret = -EINVAL; break; diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h index f86d1c776078..8ad3cece5440 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -88,6 +88,7 @@ enum { IORING_OP_READ, IORING_OP_WRITE, IORING_OP_FADVISE, + IORING_OP_MADVISE,
/* this goes last, obviously */ IORING_OP_LAST,