[PATCH 3/3] f2fs: fix inode rwsem regression

Goldwyn Rodrigues
2019-09-11T16:45:32Z

From: Goldwyn Rodrigues <rgoldwyn@suse.com>

This is similar to 942491c9e6d6 ("xfs: fix AIM7 regression")
Apparently our current rwsem code doesn't like doing the trylock, then
lock for real scheme. So change our read/write methods to just do the
trylock for the RWF_NOWAIT case.

We don't need a check for IOCB_NOWAIT and !direct-IO because it
is checked in generic_write_checks().

Fixes: b91050a80cec ("f2fs: add nowait aio support")
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@suse.com>
---
fs/f2fs/file.c | 10 +++-------
1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 3e58a6f697dd..c6f3ef815c05 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -3134,16 +3134,12 @@ static ssize_t f2fs_file_write_iter(struct kiocb *iocb, struct iov_iter *from)
goto out;
}

- if ((iocb->ki_flags & IOCB_NOWAIT) && !(iocb->ki_flags & IOCB_DIRECT)) {
- ret = -EINVAL;
- goto out;
- }
-
- if (!inode_trylock(inode)) {
- if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (iocb->ki_flags & IOCB_NOWAIT) {
+ if (!inode_trylock(inode)) {
ret = -EAGAIN;
goto out;
}
+ } else {
inode_lock(inode);
}

--
2.16.4