[PATCH 3.18 096/183] dm: fix missed error code if .end_io isnt implemented by target_type

Greg Kroah-Hartman
2015-01-25T18:45:05Z

From: zhendong chen <alex.chen@huawei.com>

commit 5164bece1673cdf04782f8ed3fba70743700f5da upstream.

In bio-based DM's clone_endio(), when target_type doesn't implement
.end_io (e.g. linear) r will be always be initialized 0. So if a
WRITE SAME bio fails WRITE SAME will not be disabled as intended.

Fix this by initializing r to error, rather than 0, in clone_endio().

Signed-off-by: Alex Chen <alex.chen@huawei.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Fixes: 7eee4ae2db ("dm: disable WRITE SAME if it fails")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/md/dm.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -899,7 +899,7 @@ static void disable_write_same(struct ma

static void clone_endio(struct bio *bio, int error)
{
- int r = 0;
+ int r = error;
struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone);
struct dm_io *io = tio->io;
struct mapped_device *md = tio->io->md;