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: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2019-11-23 14:24:24 -07:00
parent bd3ded3146
commit f8e85cf255
2 changed files with 37 additions and 0 deletions

View file

@ -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;

View file

@ -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