Commit c16b52a0 authored by Keith Busch's avatar Keith Busch Committed by Jens Axboe
Browse files

blk-integrity: use iterator for mapping sg 



Modify blk_rq_map_integrity_sg to use the blk-mq mapping iterator. This
produces more efficient code and converges the integrity mapping
implementations to reduce future maintenance burdens.

The function implementation moves from blk-integrity.c to blk-mq-dma.c
in order to use the types and functions private to that file.

Signed-off-by: default avatarKeith Busch <kbusch@kernel.org>
Reviewed-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20250813153153.3260897-8-kbusch@meta.com


Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent fec9b16d

block/blk-integrity.c

+0 −58
Original line number Diff line number Diff line
@@ -122,64 +122,6 @@ int blk_get_meta_cap(struct block_device *bdev, unsigned int cmd, 
				   NULL);

}



/**

 * blk_rq_map_integrity_sg - Map integrity metadata into a scatterlist

 * @rq:		request to map

 * @sglist:	target scatterlist

 *

 * Description: Map the integrity vectors in request into a

 * scatterlist.  The scatterlist must be big enough to hold all

 * elements.  I.e. sized using blk_rq_count_integrity_sg() or

 * rq->nr_integrity_segments.

 */

int blk_rq_map_integrity_sg(struct request *rq, struct scatterlist *sglist)

{

	struct bio_vec iv, ivprv = { NULL };

	struct request_queue *q = rq->q;

	struct scatterlist *sg = NULL;

	struct bio *bio = rq->bio;

	unsigned int segments = 0;

	struct bvec_iter iter;

	int prev = 0;



	bio_for_each_integrity_vec(iv, bio, iter) {

		if (prev) {

			if (!biovec_phys_mergeable(q, &ivprv, &iv))

				goto new_segment;

			if (sg->length + iv.bv_len > queue_max_segment_size(q))

				goto new_segment;



			sg->length += iv.bv_len;

		} else {

new_segment:

			if (!sg)

				sg = sglist;

			else {

				sg_unmark_end(sg);

				sg = sg_next(sg);

			}



			sg_set_page(sg, iv.bv_page, iv.bv_len, iv.bv_offset);

			segments++;

		}



		prev = 1;

		ivprv = iv;

	}



	if (sg)

		sg_mark_end(sg);



	/*

	 * Something must have been wrong if the figured number of segment

	 * is bigger than number of req's physical integrity segments

	 */

	BUG_ON(segments > rq->nr_integrity_segments);

	BUG_ON(segments > queue_max_integrity_segments(q));

	return segments;

}

EXPORT_SYMBOL(blk_rq_map_integrity_sg);



int blk_rq_integrity_map_user(struct request *rq, void __user *ubuf,

			      ssize_t bytes)

{

block/blk-mq-dma.c

+45 −0
Original line number Diff line number Diff line
@@ -379,4 +379,49 @@ bool blk_rq_integrity_dma_map_iter_next(struct request *req, 
	return blk_dma_map_direct(req, dma_dev, iter, &vec);

}

EXPORT_SYMBOL_GPL(blk_rq_integrity_dma_map_iter_next);



/**

 * blk_rq_map_integrity_sg - Map integrity metadata into a scatterlist

 * @rq:		request to map

 * @sglist:	target scatterlist

 *

 * Description: Map the integrity vectors in request into a

 * scatterlist.  The scatterlist must be big enough to hold all

 * elements.  I.e. sized using blk_rq_count_integrity_sg() or

 * rq->nr_integrity_segments.

 */

int blk_rq_map_integrity_sg(struct request *rq, struct scatterlist *sglist)

{

	struct request_queue *q = rq->q;

	struct scatterlist *sg = NULL;

	struct bio *bio = rq->bio;

	unsigned int segments = 0;

	struct phys_vec vec;



	struct blk_map_iter iter = {

		.bio = bio,

		.iter = bio_integrity(bio)->bip_iter,

		.bvecs = bio_integrity(bio)->bip_vec,

		.is_integrity = true,

	};



	while (blk_map_iter_next(rq, &iter, &vec)) {

		sg = blk_next_sg(&sg, sglist);

		sg_set_page(sg, phys_to_page(vec.paddr), vec.len,

				offset_in_page(vec.paddr));

		segments++;

	}



	if (sg)

	        sg_mark_end(sg);



	/*

	 * Something must have been wrong if the figured number of segment

	 * is bigger than number of req's physical integrity segments

	 */

	BUG_ON(segments > rq->nr_integrity_segments);

	BUG_ON(segments > queue_max_integrity_segments(q));

	return segments;

}

EXPORT_SYMBOL(blk_rq_map_integrity_sg);

#endif