[PATCH V6 16/30] dm: clone bio via bio_clone_chunk_bioset

Ming Lei
2018-06-09T12:30:00Z

The incoming bio will become very big after multipage bvec is enabled,
so we can't clone bio page by page.

This patch uses the introduced bio_clone_chunk_bioset(), so the incoming
bio can be cloned successfully. This way is safe because device mapping
won't modify the bio vector on the cloned multipage bio.

Signed-off-by: Ming Lei <ming.lei@redhat.com>
---
drivers/md/dm.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 98dff36b89a3..13ca3574d972 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -1582,8 +1582,8 @@ static blk_qc_t __split_and_process_bio(struct mapped_device *md,
* the usage of io->orig_bio in dm_remap_zone_report()
* won't be affected by this reassignment.
*/
- struct bio *b = bio_clone_bioset(bio, GFP_NOIO,
- &md->queue->bio_split);
+ struct bio *b = bio_clone_chunk_bioset(bio, GFP_NOIO,
+ &md->queue->bio_split);
ci.io->orig_bio = b;
bio_advance(bio, (bio_sectors(bio) - ci.sector_count) << 9);
bio_chain(b, bio);
--
2.9.5