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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
33/*
34 * Bits for request->gstate. The lower two bits carry MQ_RQ_* state value
35 * and the upper bits the generation number.
36 */
37enum mq_rq_state {
38 MQ_RQ_IDLE = 0,
39 MQ_RQ_IN_FLIGHT = 1,
40 MQ_RQ_COMPLETE = 2,
41
42 MQ_RQ_STATE_BITS = 2,
43 MQ_RQ_STATE_MASK = (1 << MQ_RQ_STATE_BITS) - 1,
44 MQ_RQ_GEN_INC = 1 << MQ_RQ_STATE_BITS,
45};
46
47void blk_mq_freeze_queue(struct request_queue *q);
48void blk_mq_free_queue(struct request_queue *q);
49int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
50void blk_mq_wake_waiters(struct request_queue *q);
51bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool);
52void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
53bool blk_mq_get_driver_tag(struct request *rq, struct blk_mq_hw_ctx **hctx,
54 bool wait);
55struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
56 struct blk_mq_ctx *start);
57
58/*
59 * Internal helpers for allocating/freeing the request map
60 */
61void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
62 unsigned int hctx_idx);
63void blk_mq_free_rq_map(struct blk_mq_tags *tags);
64struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
65 unsigned int hctx_idx,
66 unsigned int nr_tags,
67 unsigned int reserved_tags);
68int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
69 unsigned int hctx_idx, unsigned int depth);
70
71/*
72 * Internal helpers for request insertion into sw queues
73 */
74void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
75 bool at_head);
76void blk_mq_request_bypass_insert(struct request *rq, bool run_queue);
77void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
78 struct list_head *list);
79
80/* Used by blk_insert_cloned_request() to issue request directly */
81blk_status_t blk_mq_request_issue_directly(struct request *rq);
82
83/*
84 * CPU -> queue mappings
85 */
86extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);
87
88static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
89 int cpu)
90{
91 return q->queue_hw_ctx[q->mq_map[cpu]];
92}
93
94/*
95 * sysfs helpers
96 */
97extern void blk_mq_sysfs_init(struct request_queue *q);
98extern void blk_mq_sysfs_deinit(struct request_queue *q);
99extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q);
100extern int blk_mq_sysfs_register(struct request_queue *q);
101extern void blk_mq_sysfs_unregister(struct request_queue *q);
102extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
103
104void blk_mq_release(struct request_queue *q);
105
106/**
107 * blk_mq_rq_state() - read the current MQ_RQ_* state of a request
108 * @rq: target request.
109 */
110static inline int blk_mq_rq_state(struct request *rq)
111{
112 return READ_ONCE(rq->gstate) & MQ_RQ_STATE_MASK;
113}
114
115/**
116 * blk_mq_rq_update_state() - set the current MQ_RQ_* state of a request
117 * @rq: target request.
118 * @state: new state to set.
119 *
120 * Set @rq's state to @state. The caller is responsible for ensuring that
121 * there are no other updaters. A request can transition into IN_FLIGHT
122 * only from IDLE and doing so increments the generation number.
123 */
124static inline void blk_mq_rq_update_state(struct request *rq,
125 enum mq_rq_state state)
126{
127 u64 old_val = READ_ONCE(rq->gstate);
128 u64 new_val = (old_val & ~MQ_RQ_STATE_MASK) | state;
129
130 if (state == MQ_RQ_IN_FLIGHT) {
131 WARN_ON_ONCE((old_val & MQ_RQ_STATE_MASK) != MQ_RQ_IDLE);
132 new_val += MQ_RQ_GEN_INC;
133 }
134
135 /* avoid exposing interim values */
136 WRITE_ONCE(rq->gstate, new_val);
137}
138
139static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
140 unsigned int cpu)
141{
142 return per_cpu_ptr(q->queue_ctx, cpu);
143}
144
145/*
146 * This assumes per-cpu software queueing queues. They could be per-node
147 * as well, for instance. For now this is hardcoded as-is. Note that we don't
148 * care about preemption, since we know the ctx's are persistent. This does
149 * mean that we can't rely on ctx always matching the currently running CPU.
150 */
151static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
152{
153 return __blk_mq_get_ctx(q, get_cpu());
154}
155
156static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
157{
158 put_cpu();
159}
160
161struct blk_mq_alloc_data {
162 /* input parameter */
163 struct request_queue *q;
164 blk_mq_req_flags_t flags;
165 unsigned int shallow_depth;
166
167 /* input & output parameter */
168 struct blk_mq_ctx *ctx;
169 struct blk_mq_hw_ctx *hctx;
170};
171
172static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
173{
174 if (data->flags & BLK_MQ_REQ_INTERNAL)
175 return data->hctx->sched_tags;
176
177 return data->hctx->tags;
178}
179
180static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
181{
182 return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
183}
184
185static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
186{
187 return hctx->nr_ctx && hctx->tags;
188}
189
190void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
191 unsigned int inflight[2]);
192void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
193 unsigned int inflight[2]);
194
195static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx)
196{
197 struct request_queue *q = hctx->queue;
198
199 if (q->mq_ops->put_budget)
200 q->mq_ops->put_budget(hctx);
201}
202
203static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx)
204{
205 struct request_queue *q = hctx->queue;
206
207 if (q->mq_ops->get_budget)
208 return q->mq_ops->get_budget(hctx);
209 return true;
210}
211
212static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
213 struct request *rq)
214{
215 blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag);
216 rq->tag = -1;
217
218 if (rq->rq_flags & RQF_MQ_INFLIGHT) {
219 rq->rq_flags &= ~RQF_MQ_INFLIGHT;
220 atomic_dec(&hctx->nr_active);
221 }
222}
223
224static inline void blk_mq_put_driver_tag_hctx(struct blk_mq_hw_ctx *hctx,
225 struct request *rq)
226{
227 if (rq->tag == -1 || rq->internal_tag == -1)
228 return;
229
230 __blk_mq_put_driver_tag(hctx, rq);
231}
232
233static inline void blk_mq_put_driver_tag(struct request *rq)
234{
235 struct blk_mq_hw_ctx *hctx;
236
237 if (rq->tag == -1 || rq->internal_tag == -1)
238 return;
239
240 hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu);
241 __blk_mq_put_driver_tag(hctx, rq);
242}
243
244#endif
1#ifndef INT_BLK_MQ_H
2#define INT_BLK_MQ_H
3
4#include "blk-stat.h"
5
6struct blk_mq_tag_set;
7
8struct blk_mq_ctx {
9 struct {
10 spinlock_t lock;
11 struct list_head rq_list;
12 } ____cacheline_aligned_in_smp;
13
14 unsigned int cpu;
15 unsigned int index_hw;
16
17 /* incremented at dispatch time */
18 unsigned long rq_dispatched[2];
19 unsigned long rq_merged;
20
21 /* incremented at completion time */
22 unsigned long ____cacheline_aligned_in_smp rq_completed[2];
23 struct blk_rq_stat stat[2];
24
25 struct request_queue *queue;
26 struct kobject kobj;
27} ____cacheline_aligned_in_smp;
28
29void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
30void blk_mq_freeze_queue(struct request_queue *q);
31void blk_mq_free_queue(struct request_queue *q);
32int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
33void blk_mq_wake_waiters(struct request_queue *q);
34bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *, struct list_head *);
35
36/*
37 * CPU hotplug helpers
38 */
39void blk_mq_enable_hotplug(void);
40void blk_mq_disable_hotplug(void);
41
42/*
43 * CPU -> queue mappings
44 */
45extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);
46
47static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
48 int cpu)
49{
50 return q->queue_hw_ctx[q->mq_map[cpu]];
51}
52
53/*
54 * sysfs helpers
55 */
56extern int blk_mq_sysfs_register(struct request_queue *q);
57extern void blk_mq_sysfs_unregister(struct request_queue *q);
58extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
59
60extern void blk_mq_rq_timed_out(struct request *req, bool reserved);
61
62void blk_mq_release(struct request_queue *q);
63
64static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
65 unsigned int cpu)
66{
67 return per_cpu_ptr(q->queue_ctx, cpu);
68}
69
70/*
71 * This assumes per-cpu software queueing queues. They could be per-node
72 * as well, for instance. For now this is hardcoded as-is. Note that we don't
73 * care about preemption, since we know the ctx's are persistent. This does
74 * mean that we can't rely on ctx always matching the currently running CPU.
75 */
76static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
77{
78 return __blk_mq_get_ctx(q, get_cpu());
79}
80
81static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
82{
83 put_cpu();
84}
85
86struct blk_mq_alloc_data {
87 /* input parameter */
88 struct request_queue *q;
89 unsigned int flags;
90
91 /* input & output parameter */
92 struct blk_mq_ctx *ctx;
93 struct blk_mq_hw_ctx *hctx;
94};
95
96static inline void blk_mq_set_alloc_data(struct blk_mq_alloc_data *data,
97 struct request_queue *q, unsigned int flags,
98 struct blk_mq_ctx *ctx, struct blk_mq_hw_ctx *hctx)
99{
100 data->q = q;
101 data->flags = flags;
102 data->ctx = ctx;
103 data->hctx = hctx;
104}
105
106static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
107{
108 return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
109}
110
111static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
112{
113 return hctx->nr_ctx && hctx->tags;
114}
115
116#endif