[PATCH AUTOSEL 4.20 42/77] dm: fix clone_bio() to trigger blk_recount_segments()

From: Sasha Levin
Date: Thu Feb 14 2019 - 21:39:50 EST


From: Mike Snitzer <snitzer@xxxxxxxxxx>

[ Upstream commit 57c36519e4b949f89381053f7283f5d605595b42 ]

DM's clone_bio() now benefits from using bio_trim() by fixing the fact
that clone_bio() wasn't clearing BIO_SEG_VALID like bio_trim() does;
which triggers blk_recount_segments() via bio_phys_segments().

Reviewed-by: Ming Lei <ming.lei@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/md/dm.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 63a7c416b224..7138e69d40e0 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1318,7 +1318,7 @@ static int clone_bio(struct dm_target_io *tio, struct bio *bio,

__bio_clone_fast(clone, bio);

- if (unlikely(bio_integrity(bio) != NULL)) {
+ if (bio_integrity(bio)) {
int r;

if (unlikely(!dm_target_has_integrity(tio->ti->type) &&
@@ -1334,11 +1334,7 @@ static int clone_bio(struct dm_target_io *tio, struct bio *bio,
return r;
}

- bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector));
- clone->bi_iter.bi_size = to_bytes(len);
-
- if (unlikely(bio_integrity(bio) != NULL))
- bio_integrity_trim(clone);
+ bio_trim(clone, sector - clone->bi_iter.bi_sector, len);

return 0;
}
--
2.19.1