diff options
| author | Omar Sandoval <osandov@fb.com> | 2020-04-16 14:46:12 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-06-20 10:23:23 +0200 |
| commit | 9cd3c1b207847c70d36363dd5fc63ff6e9475b03 (patch) | |
| tree | 80726e590584f24d95bf379b2b4253d37d842958 /fs | |
| parent | dacdd5c651b888b8f437ba2515d8df2342e71891 (diff) | |
btrfs: fix error handling when submitting direct I/O bio
[ Upstream commit 6d3113a193e3385c72240096fe397618ecab6e43 ]
In btrfs_submit_direct_hook(), if a direct I/O write doesn't span a RAID
stripe or chunk, we submit orig_bio without cloning it. In this case, we
don't increment pending_bios. Then, if btrfs_submit_dio_bio() fails, we
decrement pending_bios to -1, and we never complete orig_bio. Fix it by
initializing pending_bios to 1 instead of incrementing later.
Fixing this exposes another bug: we put orig_bio prematurely and then
put it again from end_io. Fix it by not putting orig_bio.
After this change, pending_bios is really more of a reference count, but
I'll leave that cleanup separate to keep the fix small.
Fixes: e65e15355429 ("btrfs: fix panic caused by direct IO")
CC: stable@vger.kernel.org # 4.4+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/inode.c | 6 |
1 files changed, 3 insertions, 3 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 548e9cd1a337..972475eeb2dd 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -8294,7 +8294,6 @@ static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip, bio->bi_private = dip; bio->bi_end_io = btrfs_end_dio_bio; btrfs_io_bio(bio)->logical = file_offset; - atomic_inc(&dip->pending_bios); while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) { if (map_length < submit_len + bvec->bv_len || @@ -8351,7 +8350,8 @@ submit: if (!ret) return 0; - bio_put(bio); + if (bio != orig_bio) + bio_put(bio); out_err: dip->errors = 1; /* @@ -8398,7 +8398,7 @@ static void btrfs_submit_direct(int rw, struct bio *dio_bio, io_bio->bi_private = dip; dip->orig_bio = io_bio; dip->dio_bio = dio_bio; - atomic_set(&dip->pending_bios, 0); + atomic_set(&dip->pending_bios, 1); btrfs_bio = btrfs_io_bio(io_bio); btrfs_bio->logical = file_offset; |