Commit e9cd19c0 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jens Axboe
Browse files

block: simplify blk_recalc_rq_segments 



Return the segement and let the callers assign them, which makes the code
a littler more obvious.  Also pass the request instead of q plus bio
chain, allowing for the use of rq_for_each_bvec.

Reviewed-by: default avatarHannes Reinecke <hare@suse.com>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 14ccb66b

block/blk-core.c

+2 −2
Original line number Diff line number Diff line
@@ -1152,7 +1152,7 @@ static int blk_cloned_rq_check_limits(struct request_queue *q, 
	 * Recalculate it to check the request correctly on this queue's

	 * limitation.

	 */

	blk_recalc_rq_segments(rq);

	rq->nr_phys_segments = blk_recalc_rq_segments(rq);

	if (rq->nr_phys_segments > queue_max_segments(q)) {

		printk(KERN_ERR "%s: over max segments limit. (%hu > %hu)\n",

			__func__, rq->nr_phys_segments, queue_max_segments(q));
@@ -1421,7 +1421,7 @@ bool blk_update_request(struct request *req, blk_status_t error, 
		}



		/* recalculate the number of segments */

		blk_recalc_rq_segments(req);

		req->nr_phys_segments = blk_recalc_rq_segments(req);

	}



	return true;

block/blk-merge.c

+6 −15
Original line number Diff line number Diff line
@@ -310,17 +310,16 @@ void blk_queue_split(struct request_queue *q, struct bio **bio) 
}

EXPORT_SYMBOL(blk_queue_split);



static unsigned int __blk_recalc_rq_segments(struct request_queue *q,

					     struct bio *bio)

unsigned int blk_recalc_rq_segments(struct request *rq)

{

	unsigned int nr_phys_segs = 0;

	struct bvec_iter iter;

	struct req_iterator iter;

	struct bio_vec bv;



	if (!bio)

	if (!rq->bio)

		return 0;



	switch (bio_op(bio)) {

	switch (bio_op(rq->bio)) {

	case REQ_OP_DISCARD:

	case REQ_OP_SECURE_ERASE:

	case REQ_OP_WRITE_ZEROES:
@@ -329,19 +328,11 @@ static unsigned int __blk_recalc_rq_segments(struct request_queue *q, 
		return 1;

	}



	for_each_bio(bio) {

		bio_for_each_bvec(bv, bio, iter)

			bvec_split_segs(q, &bv, &nr_phys_segs, NULL, UINT_MAX);

	}



	rq_for_each_bvec(bv, rq, iter)

		bvec_split_segs(rq->q, &bv, &nr_phys_segs, NULL, UINT_MAX);

	return nr_phys_segs;

}



void blk_recalc_rq_segments(struct request *rq)

{

	rq->nr_phys_segments = __blk_recalc_rq_segments(rq->q, rq->bio);

}



static inline struct scatterlist *blk_next_sg(struct scatterlist **sg,

		struct scatterlist *sglist)

{

block/blk.h

+1 −1
Original line number Diff line number Diff line
@@ -211,7 +211,7 @@ struct request *attempt_back_merge(struct request_queue *q, struct request *rq); 
struct request *attempt_front_merge(struct request_queue *q, struct request *rq);

int blk_attempt_req_merge(struct request_queue *q, struct request *rq,

				struct request *next);

void blk_recalc_rq_segments(struct request *rq);

unsigned int blk_recalc_rq_segments(struct request *rq);

void blk_rq_set_mixed_merge(struct request *rq);

bool blk_rq_merge_ok(struct request *rq, struct bio *bio);

enum elv_merge blk_try_merge(struct request *rq, struct bio *bio);

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