summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorOmar Sandoval <osandov@fb.com>2020-04-16 14:46:12 -0700
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2020-06-22 09:05:26 +0200
commit74bee8344b7defb5dd41de37290df51bc9e12f5e (patch)
tree459af8f7555d2f678f065c2d759a203bf28d2e51
parent3bd1e2596ba3c97cb183380284566ea52716ae8a (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>
-rw-r--r--fs/btrfs/inode.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index c69e5b255745..b4f295a058d8 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -8399,7 +8399,6 @@ static int btrfs_submit_direct_hook(struct btrfs_dio_private *dip)
/* bio split */
ASSERT(map_length <= INT_MAX);
- atomic_inc(&dip->pending_bios);
do {
clone_len = min_t(int, submit_len, map_length);
@@ -8450,7 +8449,8 @@ submit:
if (!status)
return 0;
- bio_put(bio);
+ if (bio != orig_bio)
+ bio_put(bio);
out_err:
dip->errors = 1;
/*
@@ -8491,7 +8491,7 @@ static void btrfs_submit_direct(struct bio *dio_bio, struct inode *inode,
bio->bi_private = dip;
dip->orig_bio = bio;
dip->dio_bio = dio_bio;
- atomic_set(&dip->pending_bios, 0);
+ atomic_set(&dip->pending_bios, 1);
io_bio = btrfs_io_bio(bio);
io_bio->logical = file_offset;