Pipe reads or writes need to enable nonblocking attempts, if either
O_NONBLOCK is set on the file, or IOCB_NOWAIT is set in the iocb being
passed in. The latter isn't currently true, ensure we check for both
before waiting on data or space.
Fixes: afed6271f5b0 ("pipe: set FMODE_NOWAIT on pipes")
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
With the pipe nonblock rework, these two hunsk from one of the other
patches was inadvertently dropped. We obviously need to check both,
or files without O_NONBLOCK but IOCB_NOWAIT set in the iocb will still
block on space/data when writing/reading to/from a pipe.
I can just include this in the io_uring changes as it directly impacts
io_uring (breaking a few test cases), or you guys can queue it up on
the VFS side. Would be great to get this in -rc2 as it's stalling
the regression testing with the vanilla kernels.
diff --git a/fs/pipe.c b/fs/pipe.c
index ceb17d2dfa19..c88611c612ba 100644
--- a/fs/pipe.c
+++ b/fs/pipe.c
@@ -342,7 +342,7 @@ pipe_read(struct kiocb *iocb, struct iov_iter *to)
break;
if (ret)
break;
- if (filp->f_flags & O_NONBLOCK) {
+ if (filp->f_flags & O_NONBLOCK || iocb->ki_flags & IOCB_NOWAIT) {
ret = -EAGAIN;
break;
}
@@ -547,7 +547,7 @@ pipe_write(struct kiocb *iocb, struct iov_iter *from)
continue;
/* Wait for buffer space to become available. */
- if (filp->f_flags & O_NONBLOCK) {
+ if (filp->f_flags & O_NONBLOCK || iocb->ki_flags & IOCB_NOWAIT) {
if (!ret)
ret = -EAGAIN;
break;
--
Jens Axboe
