xref: /openbmc/linux/block/blk-mq-sched.h (revision 3ca3af7d)
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 #include "blk-mq-tag.h"
8 
9 #define MAX_SCHED_RQ (16 * BLKDEV_DEFAULT_RQ)
10 
11 void blk_mq_sched_assign_ioc(struct request *rq);
12 
13 bool blk_mq_sched_try_merge(struct request_queue *q, struct bio *bio,
14 		unsigned int nr_segs, struct request **merged_request);
15 bool blk_mq_sched_bio_merge(struct request_queue *q, struct bio *bio,
16 		unsigned int nr_segs);
17 bool blk_mq_sched_try_insert_merge(struct request_queue *q, struct request *rq,
18 				   struct list_head *free);
19 void blk_mq_sched_mark_restart_hctx(struct blk_mq_hw_ctx *hctx);
20 void __blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx);
21 
22 void blk_mq_sched_insert_request(struct request *rq, bool at_head,
23 				 bool run_queue, bool async);
24 void blk_mq_sched_insert_requests(struct blk_mq_hw_ctx *hctx,
25 				  struct blk_mq_ctx *ctx,
26 				  struct list_head *list, bool run_queue_async);
27 
28 void blk_mq_sched_dispatch_requests(struct blk_mq_hw_ctx *hctx);
29 
30 int blk_mq_init_sched(struct request_queue *q, struct elevator_type *e);
31 void blk_mq_exit_sched(struct request_queue *q, struct elevator_queue *e);
32 void blk_mq_sched_free_rqs(struct request_queue *q);
33 
34 static inline void blk_mq_sched_restart(struct blk_mq_hw_ctx *hctx)
35 {
36 	if (test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state))
37 		__blk_mq_sched_restart(hctx);
38 }
39 
40 static inline bool bio_mergeable(struct bio *bio)
41 {
42 	return !(bio->bi_opf & REQ_NOMERGE_FLAGS);
43 }
44 
45 static inline bool
46 blk_mq_sched_allow_merge(struct request_queue *q, struct request *rq,
47 			 struct bio *bio)
48 {
49 	if (rq->rq_flags & RQF_ELV) {
50 		struct elevator_queue *e = q->elevator;
51 
52 		if (e->type->ops.allow_merge)
53 			return e->type->ops.allow_merge(q, rq, bio);
54 	}
55 	return true;
56 }
57 
58 static inline void blk_mq_sched_completed_request(struct request *rq, u64 now)
59 {
60 	if (rq->rq_flags & RQF_ELV) {
61 		struct elevator_queue *e = rq->q->elevator;
62 
63 		if (e->type->ops.completed_request)
64 			e->type->ops.completed_request(rq, now);
65 	}
66 }
67 
68 static inline void blk_mq_sched_requeue_request(struct request *rq)
69 {
70 	if (rq->rq_flags & RQF_ELV) {
71 		struct request_queue *q = rq->q;
72 		struct elevator_queue *e = q->elevator;
73 
74 		if ((rq->rq_flags & RQF_ELVPRIV) && e->type->ops.requeue_request)
75 			e->type->ops.requeue_request(rq);
76 	}
77 }
78 
79 static inline bool blk_mq_sched_has_work(struct blk_mq_hw_ctx *hctx)
80 {
81 	struct elevator_queue *e = hctx->queue->elevator;
82 
83 	if (e && e->type->ops.has_work)
84 		return e->type->ops.has_work(hctx);
85 
86 	return false;
87 }
88 
89 static inline bool blk_mq_sched_needs_restart(struct blk_mq_hw_ctx *hctx)
90 {
91 	return test_bit(BLK_MQ_S_SCHED_RESTART, &hctx->state);
92 }
93 
94 #endif
95