dm: remove check that prevents mapping empty bios

Remove the check that the size of the cloned bio is not zero because a
subsequent patch needs to send zero-sized barriers down this path.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 8498dc4..7d9ca70 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -637,11 +637,6 @@ static void __map_bio(struct dm_target *ti, struct bio *clone,
        sector_t sector;
        struct mapped_device *md;
 
-       /*
-        * Sanity checks.
-        */
-       BUG_ON(!clone->bi_size);
-
        clone->bi_end_io = clone_endio;
        clone->bi_private = tio;