Commit 764f612c authored by Ming Lei's avatar Ming Lei Committed by Jens Axboe
Browse files

blk-merge: don't compute bi_phys_segments from bi_vcnt for cloned bio 



It isn't correct to figure out req->bi_phys_segments from bio->bi_vcnt
if the bio is cloned.

Signed-off-by: default avatarMing Lei <ming.lei@canonical.com>
Tested-by: default avatarJeff Mahoney <jeffm@suse.com>
Signed-off-by: default avatarJens Axboe <axboe@fb.com>
parent b8839b8c

block/blk-merge.c

+6 −2
Original line number Diff line number Diff line
@@ -97,14 +97,18 @@ void blk_recalc_rq_segments(struct request *rq) 


void blk_recount_segments(struct request_queue *q, struct bio *bio)

{

	if (test_bit(QUEUE_FLAG_NO_SG_MERGE, &q->queue_flags) &&

	bool no_sg_merge = !!test_bit(QUEUE_FLAG_NO_SG_MERGE,

			&q->queue_flags);



	if (no_sg_merge && !bio_flagged(bio, BIO_CLONED) &&

			bio->bi_vcnt < queue_max_segments(q))

		bio->bi_phys_segments = bio->bi_vcnt;

	else {

		struct bio *nxt = bio->bi_next;



		bio->bi_next = NULL;

		bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio, false);

		bio->bi_phys_segments = __blk_recalc_rq_segments(q, bio,

				no_sg_merge);

		bio->bi_next = nxt;

	}