From: Jens Axboe axboe@kernel.dk
mainline inclusion from mainline-5.5-rc1 commit 17f2fe35d080d8f64e86a60cdcd3a97edcbc213b category: feature bugzilla: https://bugzilla.openeuler.org/show_bug.cgi?id=27 CVE: NA ---------------------------
This allows an application to call accept4() in an async fashion. Like other opcodes, we first try a non-blocking accept, then punt to async context if we have to.
Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Zhihao Cheng chengzhihao1@huawei.com 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 | 37 +++++++++++++++++++++++++++++++++++ include/uapi/linux/io_uring.h | 7 ++++++- 2 files changed, 43 insertions(+), 1 deletion(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c index 7cf028b1de47..18b42f21aadd 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1685,6 +1685,40 @@ static int io_recvmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe, #endif }
+static int io_accept(struct io_kiocb *req, const struct io_uring_sqe *sqe, + struct io_kiocb **nxt, bool force_nonblock) +{ +#if defined(CONFIG_NET) + struct sockaddr __user *addr; + int __user *addr_len; + unsigned file_flags; + int flags, ret; + + if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) + return -EINVAL; + if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index) + return -EINVAL; + + addr = (struct sockaddr __user *) (unsigned long) READ_ONCE(sqe->addr); + addr_len = (int __user *) (unsigned long) READ_ONCE(sqe->addr2); + flags = READ_ONCE(sqe->accept_flags); + file_flags = force_nonblock ? O_NONBLOCK : 0; + + ret = __sys_accept4_file(req->file, file_flags, addr, addr_len, flags); + if (ret == -EAGAIN && force_nonblock) { + req->work.flags |= IO_WQ_WORK_NEEDS_FILES; + return -EAGAIN; + } + if (ret < 0 && (req->flags & REQ_F_LINK)) + req->flags |= REQ_F_FAIL_LINK; + io_cqring_add_event(req->ctx, sqe->user_data, ret); + io_put_req(req, nxt); + return 0; +#else + return -EOPNOTSUPP; +#endif +} + static void io_poll_remove_one(struct io_kiocb *req) { struct io_poll_iocb *poll = &req->poll; @@ -2172,6 +2206,9 @@ static int __io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req, case IORING_OP_TIMEOUT_REMOVE: ret = io_timeout_remove(req, s->sqe); break; + case IORING_OP_ACCEPT: + ret = io_accept(req, s->sqe, 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 6dc5ced1c37a..f82d90e617a6 100644 --- a/include/uapi/linux/io_uring.h +++ b/include/uapi/linux/io_uring.h @@ -19,7 +19,10 @@ struct io_uring_sqe { __u8 flags; /* IOSQE_ flags */ __u16 ioprio; /* ioprio for the request */ __s32 fd; /* file descriptor to do IO on */ - __u64 off; /* offset into file */ + union { + __u64 off; /* offset into file */ + __u64 addr2; + }; __u64 addr; /* pointer to buffer or iovecs */ __u32 len; /* buffer size or number of iovecs */ union { @@ -29,6 +32,7 @@ struct io_uring_sqe { __u32 sync_range_flags; __u32 msg_flags; __u32 timeout_flags; + __u32 accept_flags; }; __u64 user_data; /* data to be passed back at completion time */ union { @@ -65,6 +69,7 @@ struct io_uring_sqe { #define IORING_OP_RECVMSG 10 #define IORING_OP_TIMEOUT 11 #define IORING_OP_TIMEOUT_REMOVE 12 +#define IORING_OP_ACCEPT 13
/* * sqe->fsync_flags