Commit c5b85625 authored by Jens Axboe's avatar Jens Axboe

io_uring: allow O_NONBLOCK async retry

We can assume that O_NONBLOCK is always honored, even if we don't
have a ->read/write_iter() for the file type. Also unify the read/write
checking for allowing async punt, having the write side factoring in the
REQ_F_NOWAIT flag as well.

Cc: stable@vger.kernel.org
Fixes: 490e8967 ("io_uring: only force async punt if poll based retry can't handle it")
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent f5fa38c5
...@@ -2061,6 +2061,10 @@ static bool io_file_supports_async(struct file *file, int rw) ...@@ -2061,6 +2061,10 @@ static bool io_file_supports_async(struct file *file, int rw)
if (S_ISREG(mode) && file->f_op != &io_uring_fops) if (S_ISREG(mode) && file->f_op != &io_uring_fops)
return true; return true;
/* any ->read/write should understand O_NONBLOCK */
if (file->f_flags & O_NONBLOCK)
return true;
if (!(file->f_mode & FMODE_NOWAIT)) if (!(file->f_mode & FMODE_NOWAIT))
return false; return false;
...@@ -2103,8 +2107,7 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe, ...@@ -2103,8 +2107,7 @@ static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe,
kiocb->ki_ioprio = get_current_ioprio(); kiocb->ki_ioprio = get_current_ioprio();
/* don't allow async punt if RWF_NOWAIT was requested */ /* don't allow async punt if RWF_NOWAIT was requested */
if ((kiocb->ki_flags & IOCB_NOWAIT) || if (kiocb->ki_flags & IOCB_NOWAIT)
(req->file->f_flags & O_NONBLOCK))
req->flags |= REQ_F_NOWAIT; req->flags |= REQ_F_NOWAIT;
if (force_nonblock) if (force_nonblock)
...@@ -2745,7 +2748,8 @@ static int io_write(struct io_kiocb *req, bool force_nonblock) ...@@ -2745,7 +2748,8 @@ static int io_write(struct io_kiocb *req, bool force_nonblock)
if (ret) if (ret)
goto out_free; goto out_free;
/* any defer here is final, must blocking retry */ /* any defer here is final, must blocking retry */
if (!file_can_poll(req->file)) if (!(req->flags & REQ_F_NOWAIT) &&
!file_can_poll(req->file))
req->flags |= REQ_F_MUST_PUNT; req->flags |= REQ_F_MUST_PUNT;
return -EAGAIN; return -EAGAIN;
} }
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment