[PATCH 4.9 1/7] btrfs: mark compressed range uptodate only if all bio succeed

From: Greg Kroah-Hartman
Date: Fri Aug 06 2021 - 04:15:37 EST


From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>

[ Upstream commit 240246f6b913b0c23733cfd2def1d283f8cc9bbe ]

In compression write endio sequence, the range which the compressed_bio
writes is marked as uptodate if the last bio of the compressed (sub)bios
is completed successfully. There could be previous bio which may
have failed which is recorded in cb->errors.

Set the writeback range as uptodate only if cb->errors is zero, as opposed
to checking only the last bio's status.

Backporting notes: in all versions up to 4.4 the last argument is always
replaced by "!cb->errors".

CC: stable@xxxxxxxxxxxxxxx # 4.4+
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/btrfs/compression.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index d4d8b7e36b2f..2534e44cfd40 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -290,7 +290,7 @@ static void end_compressed_bio_write(struct bio *bio)
cb->start,
cb->start + cb->len - 1,
NULL,
- bio->bi_error ? 0 : 1);
+ !cb->errors);
cb->compressed_pages[0]->mapping = NULL;

end_compressed_writeback(inode, cb);
--
2.30.2