Commit 0d7cb52f authored Sep 13, 2024 by Keith Busch Committed by Jens Axboe Sep 13, 2024

blk-integrity: consider entire bio list for merging



If a bio is merged to a request, the entire bio list is merged, so don't
temporarily detach it from its list when counting segments. In most
cases, bi_next will already be NULL, so detaching is usually a no-op.
But if the bio does have a list, the current code is miscounting the
segments for the resulting merge.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Link: https://lore.kernel.org/r/20240913182854.2445457-5-kbusch@meta.com


Signed-off-by: Jens Axboe <axboe@kernel.dk>

parent d148d750

block/blk-integrity.c

+0 −4

Original line number	Diff line number	Diff line
		@@ -134,7 +134,6 @@ bool blk_integrity_merge_bio(struct request_queue q, struct request req,
		struct bio *bio)
		{
		int nr_integrity_segs;
		struct bio *next = bio->bi_next;

		if (blk_integrity_rq(req) == 0 && bio_integrity(bio) == NULL)
		return true;
		@@ -145,10 +144,7 @@ bool blk_integrity_merge_bio(struct request_queue q, struct request req,
		if (bio_integrity(req->bio)->bip_flags != bio_integrity(bio)->bip_flags)
		return false;

		bio->bi_next = NULL;
		nr_integrity_segs = blk_rq_count_integrity_sg(q, bio);
		bio->bi_next = next;

		if (req->nr_integrity_segments + nr_integrity_segs >
		q->limits.max_integrity_segments)
		return false;