Commit fd2d3326 authored by Jens Axboe's avatar Jens Axboe
Browse files

blk-mq: add support for carrying internal tag information in blk_qc_t 



No functional change in this patch, just in preparation for having
two types of tags available to the block layer for a single request.

Signed-off-by: default avatarJens Axboe <axboe@fb.com>
Reviewed-by: default avatarOmar Sandoval <osandov@fb.com>
parent cc71a6f4

block/blk-mq.c

+8 −3
Original line number Diff line number Diff line
@@ -1308,6 +1308,11 @@ static struct request *blk_mq_map_request(struct request_queue *q, 
	return rq;

}



static blk_qc_t request_to_qc_t(struct blk_mq_hw_ctx *hctx, struct request *rq)

{

	return blk_tag_to_qc_t(rq->tag, hctx->queue_num, false);

}



static void blk_mq_try_issue_directly(struct request *rq, blk_qc_t *cookie)

{

	int ret;
@@ -1318,7 +1323,7 @@ static void blk_mq_try_issue_directly(struct request *rq, blk_qc_t *cookie) 
		.list = NULL,

		.last = 1

	};

	blk_qc_t new_cookie = blk_tag_to_qc_t(rq->tag, hctx->queue_num);

	blk_qc_t new_cookie = request_to_qc_t(hctx, rq);



	if (blk_mq_hctx_stopped(hctx))

		goto insert;
@@ -1387,7 +1392,7 @@ static blk_qc_t blk_mq_make_request(struct request_queue *q, struct bio *bio) 


	wbt_track(&rq->issue_stat, wb_acct);



	cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num);

	cookie = request_to_qc_t(data.hctx, rq);



	if (unlikely(is_flush_fua)) {

		blk_mq_bio_to_request(rq, bio);
@@ -1496,7 +1501,7 @@ static blk_qc_t blk_sq_make_request(struct request_queue *q, struct bio *bio) 


	wbt_track(&rq->issue_stat, wb_acct);



	cookie = blk_tag_to_qc_t(rq->tag, data.hctx->queue_num);

	cookie = request_to_qc_t(data.hctx, rq);



	if (unlikely(is_flush_fua)) {

		blk_mq_bio_to_request(rq, bio);

include/linux/blk_types.h

+17 −5
Original line number Diff line number Diff line
@@ -234,20 +234,27 @@ static inline bool op_is_sync(unsigned int op) 
typedef unsigned int blk_qc_t;

#define BLK_QC_T_NONE		-1U

#define BLK_QC_T_SHIFT		16

#define BLK_QC_T_INTERNAL	(1U << 31)



static inline bool blk_qc_t_valid(blk_qc_t cookie)

{

	return cookie != BLK_QC_T_NONE;

}



static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num)

static inline blk_qc_t blk_tag_to_qc_t(unsigned int tag, unsigned int queue_num,

				       bool internal)

{

	return tag | (queue_num << BLK_QC_T_SHIFT);

	blk_qc_t ret = tag | (queue_num << BLK_QC_T_SHIFT);



	if (internal)

		ret |= BLK_QC_T_INTERNAL;



	return ret;

}



static inline unsigned int blk_qc_t_to_queue_num(blk_qc_t cookie)

{

	return cookie >> BLK_QC_T_SHIFT;

	return (cookie & ~BLK_QC_T_INTERNAL) >> BLK_QC_T_SHIFT;

}



static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie)
@@ -255,6 +262,11 @@ static inline unsigned int blk_qc_t_to_tag(blk_qc_t cookie) 
	return cookie & ((1u << BLK_QC_T_SHIFT) - 1);

}



static inline bool blk_qc_t_is_internal(blk_qc_t cookie)

{

	return (cookie & BLK_QC_T_INTERNAL) != 0;

}



struct blk_issue_stat {

	u64 time;

};