xref: /linux/block/blk-mq-sched.h (revision b1a54551dd9ed5ef1763b97b35a0999ca002b95c)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef BLK_MQ_SCHED_H
3 #define BLK_MQ_SCHED_H
4 
5 #include "elevator.h"
6 #include "blk-mq.h"
7 
8 #define MAX_SCHED_RQ (16 * BLKDEV_DEFAULT_RQ)
9 
10 bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio,
11 		unsigned int nr_segs, struct request **merged_request);
12 bool blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio,
13 		unsigned int nr_segs);
14 bool blk_mq_sched_try_insert_merge(struct request_queue *q, struct request *rq,
15 				   struct list_head *free);
16 void blk_mq_sched_mark_restart_hctx(struct blk_mq_hw_ctx *hctx);
17 void __blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx);
18 
19 void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx);
20 
21 int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e);
22 void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e);
23 void blk_mq_sched_free_rqs(struct request_queue *q);
24 
25 static inline void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx)
26 {
27 	if (test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state))
28 		__blk_mq_sched_restart(hctx);
29 }
30 
31 static inline bool bio_mergeable(struct bio *bio)
32 {
33 	return !(bio->bi_opf & REQ_NOMERGE_FLAGS);
34 }
35 
36 static inline bool
37 blk_mq_sched_allow_merge(struct request_queue *q, struct request *rq,
38 			 struct bio *bio)
39 {
40 	if (rq->rq_flags & RQF_USE_SCHED) {
41 		struct elevator_queue *e = q->elevator;
42 
43 		if (e->type->ops.allow_merge)
44 			return e->type->ops.allow_merge(q, rq, bio);
45 	}
46 	return true;
47 }
48 
49 static inline void blk_mq_sched_completed_request(struct request *rq, u64 now)
50 {
51 	if (rq->rq_flags & RQF_USE_SCHED) {
52 		struct elevator_queue *e = rq->q->elevator;
53 
54 		if (e->type->ops.completed_request)
55 			e->type->ops.completed_request(rq, now);
56 	}
57 }
58 
59 static inline void blk_mq_sched_requeue_request(struct request *rq)
60 {
61 	if (rq->rq_flags & RQF_USE_SCHED) {
62 		struct request_queue *q = rq->q;
63 		struct elevator_queue *e = q->elevator;
64 
65 		if (e->type->ops.requeue_request)
66 			e->type->ops.requeue_request(rq);
67 	}
68 }
69 
70 static inline bool blk_mq_sched_has_work(struct blk_mq_hw_ctx *hctx)
71 {
72 	struct elevator_queue *e = hctx->queue->elevator;
73 
74 	if (e && e->type->ops.has_work)
75 		return e->type->ops.has_work(hctx);
76 
77 	return false;
78 }
79 
80 static inline bool blk_mq_sched_needs_restart(struct blk_mq_hw_ctx *hctx)
81 {
82 	return test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
83 }
84 
85 #endif
86