Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef INT_BLK_MQ_H
3#define INT_BLK_MQ_H
4
5#include "blk-stat.h"
6#include "blk-mq-tag.h"
7
8struct blk_mq_tag_set;
9
10/**
11 * struct blk_mq_ctx - State for a software queue facing the submitting CPUs
12 */
13struct blk_mq_ctx {
14 struct {
15 spinlock_t lock;
16 struct list_head rq_list;
17 } ____cacheline_aligned_in_smp;
18
19 unsigned int cpu;
20 unsigned int index_hw;
21
22 /* incremented at dispatch time */
23 unsigned long rq_dispatched[2];
24 unsigned long rq_merged;
25
26 /* incremented at completion time */
27 unsigned long ____cacheline_aligned_in_smp rq_completed[2];
28
29 struct request_queue *queue;
30 struct kobject kobj;
31} ____cacheline_aligned_in_smp;
32
33void blk_mq_freeze_queue(struct request_queue *q);
34void blk_mq_free_queue(struct request_queue *q);
35int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
36void blk_mq_wake_waiters(struct request_queue *q);
37bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool);
38void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
39bool blk_mq_get_driver_tag(struct request *rq);
40struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
41 struct blk_mq_ctx *start);
42
43/*
44 * Internal helpers for allocating/freeing the request map
45 */
46void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
47 unsigned int hctx_idx);
48void blk_mq_free_rq_map(struct blk_mq_tags *tags);
49struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
50 unsigned int hctx_idx,
51 unsigned int nr_tags,
52 unsigned int reserved_tags);
53int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
54 unsigned int hctx_idx, unsigned int depth);
55
56/*
57 * Internal helpers for request insertion into sw queues
58 */
59void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
60 bool at_head);
61void blk_mq_request_bypass_insert(struct request *rq, bool run_queue);
62void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
63 struct list_head *list);
64
65/* Used by blk_insert_cloned_request() to issue request directly */
66blk_status_t blk_mq_request_issue_directly(struct request *rq);
67void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
68 struct list_head *list);
69
70/*
71 * CPU -> queue mappings
72 */
73extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);
74
75static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
76 int cpu)
77{
78 return q->queue_hw_ctx[q->mq_map[cpu]];
79}
80
81/*
82 * sysfs helpers
83 */
84extern void blk_mq_sysfs_init(struct request_queue *q);
85extern void blk_mq_sysfs_deinit(struct request_queue *q);
86extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q);
87extern int blk_mq_sysfs_register(struct request_queue *q);
88extern void blk_mq_sysfs_unregister(struct request_queue *q);
89extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
90
91void blk_mq_release(struct request_queue *q);
92
93/**
94 * blk_mq_rq_state() - read the current MQ_RQ_* state of a request
95 * @rq: target request.
96 */
97static inline enum mq_rq_state blk_mq_rq_state(struct request *rq)
98{
99 return READ_ONCE(rq->state);
100}
101
102static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
103 unsigned int cpu)
104{
105 return per_cpu_ptr(q->queue_ctx, cpu);
106}
107
108/*
109 * This assumes per-cpu software queueing queues. They could be per-node
110 * as well, for instance. For now this is hardcoded as-is. Note that we don't
111 * care about preemption, since we know the ctx's are persistent. This does
112 * mean that we can't rely on ctx always matching the currently running CPU.
113 */
114static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
115{
116 return __blk_mq_get_ctx(q, get_cpu());
117}
118
119static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
120{
121 put_cpu();
122}
123
124struct blk_mq_alloc_data {
125 /* input parameter */
126 struct request_queue *q;
127 blk_mq_req_flags_t flags;
128 unsigned int shallow_depth;
129
130 /* input & output parameter */
131 struct blk_mq_ctx *ctx;
132 struct blk_mq_hw_ctx *hctx;
133};
134
135static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
136{
137 if (data->flags & BLK_MQ_REQ_INTERNAL)
138 return data->hctx->sched_tags;
139
140 return data->hctx->tags;
141}
142
143static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
144{
145 return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
146}
147
148static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
149{
150 return hctx->nr_ctx && hctx->tags;
151}
152
153void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
154 unsigned int inflight[2]);
155void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
156 unsigned int inflight[2]);
157
158static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx)
159{
160 struct request_queue *q = hctx->queue;
161
162 if (q->mq_ops->put_budget)
163 q->mq_ops->put_budget(hctx);
164}
165
166static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx)
167{
168 struct request_queue *q = hctx->queue;
169
170 if (q->mq_ops->get_budget)
171 return q->mq_ops->get_budget(hctx);
172 return true;
173}
174
175static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
176 struct request *rq)
177{
178 blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag);
179 rq->tag = -1;
180
181 if (rq->rq_flags & RQF_MQ_INFLIGHT) {
182 rq->rq_flags &= ~RQF_MQ_INFLIGHT;
183 atomic_dec(&hctx->nr_active);
184 }
185}
186
187static inline void blk_mq_put_driver_tag_hctx(struct blk_mq_hw_ctx *hctx,
188 struct request *rq)
189{
190 if (rq->tag == -1 || rq->internal_tag == -1)
191 return;
192
193 __blk_mq_put_driver_tag(hctx, rq);
194}
195
196static inline void blk_mq_put_driver_tag(struct request *rq)
197{
198 struct blk_mq_hw_ctx *hctx;
199
200 if (rq->tag == -1 || rq->internal_tag == -1)
201 return;
202
203 hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu);
204 __blk_mq_put_driver_tag(hctx, rq);
205}
206
207static inline void blk_mq_clear_mq_map(struct blk_mq_tag_set *set)
208{
209 int cpu;
210
211 for_each_possible_cpu(cpu)
212 set->mq_map[cpu] = 0;
213}
214
215#endif