Commit f8e85cf2 authored by Jens Axboe's avatar Jens Axboe
Browse files

io_uring: add support for IORING_OP_CONNECT 



This allows an application to call connect() in an async fashion. Like
other opcodes, we first try a non-blocking connect, then punt to async
context if we have to.

Note that we can still return -EINPROGRESS, and in that case the caller
should use IORING_OP_POLL_ADD to do an async wait for completion of the
connect request (just like for regular connect(2), except we can do it
async here too).

Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent bd3ded31

fs/io_uring.c

+36 −0
Original line number Diff line number Diff line
@@ -550,6 +550,7 @@ static inline bool io_prep_async_work(struct io_kiocb *req, 
		case IORING_OP_RECVMSG:

		case IORING_OP_ACCEPT:

		case IORING_OP_POLL_ADD:

		case IORING_OP_CONNECT:

			/*

			 * We know REQ_F_ISREG is not set on some of these

			 * opcodes, but this enables us to keep the check in
@@ -1974,6 +1975,38 @@ static int io_accept(struct io_kiocb *req, const struct io_uring_sqe *sqe, 
#endif

}



static int io_connect(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;

	unsigned file_flags;

	int addr_len, ret;



	if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL)))

		return -EINVAL;

	if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags)

		return -EINVAL;



	addr = (struct sockaddr __user *) (unsigned long) READ_ONCE(sqe->addr);

	addr_len = READ_ONCE(sqe->addr2);

	file_flags = force_nonblock ? O_NONBLOCK : 0;



	ret = __sys_connect_file(req->file, addr, addr_len, file_flags);

	if (ret == -EAGAIN && force_nonblock)

		return -EAGAIN;

	if (ret == -ERESTARTSYS)

		ret = -EINTR;

	if (ret < 0 && (req->flags & REQ_F_LINK))

		req->flags |= REQ_F_FAIL_LINK;

	io_cqring_add_event(req, ret);

	io_put_req_find_next(req, nxt);

	return 0;

#else

	return -EOPNOTSUPP;

#endif

}



static inline void io_poll_remove_req(struct io_kiocb *req)

{

	if (!RB_EMPTY_NODE(&req->rb_node)) {
@@ -2637,6 +2670,9 @@ static int io_issue_sqe(struct io_kiocb *req, struct io_kiocb **nxt, 
	case IORING_OP_ACCEPT:

		ret = io_accept(req, s->sqe, nxt, force_nonblock);

		break;

	case IORING_OP_CONNECT:

		ret = io_connect(req, s->sqe, nxt, force_nonblock);

		break;

	case IORING_OP_ASYNC_CANCEL:

		ret = io_async_cancel(req, s->sqe, nxt);

		break;

include/uapi/linux/io_uring.h

+1 −0
Original line number Diff line number Diff line
@@ -73,6 +73,7 @@ struct io_uring_sqe { 
#define IORING_OP_ACCEPT	13

#define IORING_OP_ASYNC_CANCEL	14

#define IORING_OP_LINK_TIMEOUT	15

#define IORING_OP_CONNECT	16



/*

 * sqe->fsync_flags

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