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
8 struct blk_mq_tag_set;
9
10 struct blk_mq_ctxs {
11 struct kobject kobj;
12 struct blk_mq_ctx __percpu *queue_ctx;
13 };
14
15 /**
16 * struct blk_mq_ctx - State for a software queue facing the submitting CPUs
17 */
18 struct blk_mq_ctx {
19 struct {
20 spinlock_t lock;
21 struct list_head rq_lists[HCTX_MAX_TYPES];
22 } ____cacheline_aligned_in_smp;
23
24 unsigned int cpu;
25 unsigned short index_hw[HCTX_MAX_TYPES];
26 struct blk_mq_hw_ctx *hctxs[HCTX_MAX_TYPES];
27
28 /* incremented at dispatch time */
29 unsigned long rq_dispatched[2];
30 unsigned long rq_merged;
31
32 /* incremented at completion time */
33 unsigned long ____cacheline_aligned_in_smp rq_completed[2];
34
35 struct request_queue *queue;
36 struct blk_mq_ctxs *ctxs;
37 struct kobject kobj;
38
39 ANDROID_OEM_DATA_ARRAY(1, 2);
40 } ____cacheline_aligned_in_smp;
41
42 void blk_mq_exit_queue(struct request_queue *q);
43 int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
44 void blk_mq_wake_waiters(struct request_queue *q);
45 bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *,
46 unsigned int);
47 void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
48 bool kick_requeue_list);
49 void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
50 struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
51 struct blk_mq_ctx *start);
52 void blk_mq_put_rq_ref(struct request *rq);
53
54 /*
55 * Internal helpers for allocating/freeing the request map
56 */
57 void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
58 unsigned int hctx_idx);
59 void blk_mq_free_rq_map(struct blk_mq_tags *tags, unsigned int flags);
60 struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
61 unsigned int hctx_idx,
62 unsigned int nr_tags,
63 unsigned int reserved_tags,
64 unsigned int flags);
65 int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
66 unsigned int hctx_idx, unsigned int depth);
67
68 /*
69 * Internal helpers for request insertion into sw queues
70 */
71 void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
72 bool at_head);
73 void blk_mq_request_bypass_insert(struct request *rq, bool at_head,
74 bool run_queue);
75 void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
76 struct list_head *list);
77
78 /* Used by blk_insert_cloned_request() to issue request directly */
79 blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last);
80 void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
81 struct list_head *list);
82
83 /*
84 * CPU -> queue mappings
85 */
86 extern int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int);
87
88 /*
89 * blk_mq_map_queue_type() - map (hctx_type,cpu) to hardware queue
90 * @q: request queue
91 * @type: the hctx type index
92 * @cpu: CPU
93 */
blk_mq_map_queue_type(struct request_queue * q,enum hctx_type type,unsigned int cpu)94 static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q,
95 enum hctx_type type,
96 unsigned int cpu)
97 {
98 return q->queue_hw_ctx[q->tag_set->map[type].mq_map[cpu]];
99 }
100
101 /*
102 * blk_mq_map_queue() - map (cmd_flags,type) to hardware queue
103 * @q: request queue
104 * @flags: request command flags
105 * @ctx: software queue cpu ctx
106 */
blk_mq_map_queue(struct request_queue * q,unsigned int flags,struct blk_mq_ctx * ctx)107 static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
108 unsigned int flags,
109 struct blk_mq_ctx *ctx)
110 {
111 enum hctx_type type = HCTX_TYPE_DEFAULT;
112
113 /*
114 * The caller ensure that if REQ_HIPRI, poll must be enabled.
115 */
116 if (flags & REQ_HIPRI)
117 type = HCTX_TYPE_POLL;
118 else if ((flags & REQ_OP_MASK) == REQ_OP_READ)
119 type = HCTX_TYPE_READ;
120
121 return ctx->hctxs[type];
122 }
123
124 /*
125 * sysfs helpers
126 */
127 extern void blk_mq_sysfs_init(struct request_queue *q);
128 extern void blk_mq_sysfs_deinit(struct request_queue *q);
129 extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q);
130 extern int blk_mq_sysfs_register(struct request_queue *q);
131 extern void blk_mq_sysfs_unregister(struct request_queue *q);
132 extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
133
134 void blk_mq_cancel_work_sync(struct request_queue *q);
135
136 void blk_mq_release(struct request_queue *q);
137
__blk_mq_get_ctx(struct request_queue * q,unsigned int cpu)138 static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
139 unsigned int cpu)
140 {
141 return per_cpu_ptr(q->queue_ctx, cpu);
142 }
143
144 /*
145 * This assumes per-cpu software queueing queues. They could be per-node
146 * as well, for instance. For now this is hardcoded as-is. Note that we don't
147 * care about preemption, since we know the ctx's are persistent. This does
148 * mean that we can't rely on ctx always matching the currently running CPU.
149 */
blk_mq_get_ctx(struct request_queue * q)150 static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
151 {
152 return __blk_mq_get_ctx(q, raw_smp_processor_id());
153 }
154
155 struct blk_mq_alloc_data {
156 /* input parameter */
157 struct request_queue *q;
158 blk_mq_req_flags_t flags;
159 unsigned int shallow_depth;
160 unsigned int cmd_flags;
161
162 /* input & output parameter */
163 struct blk_mq_ctx *ctx;
164 struct blk_mq_hw_ctx *hctx;
165 };
166
blk_mq_is_sbitmap_shared(unsigned int flags)167 static inline bool blk_mq_is_sbitmap_shared(unsigned int flags)
168 {
169 return flags & BLK_MQ_F_TAG_HCTX_SHARED;
170 }
171
blk_mq_tags_from_data(struct blk_mq_alloc_data * data)172 static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
173 {
174 if (data->q->elevator)
175 return data->hctx->sched_tags;
176
177 return data->hctx->tags;
178 }
179
blk_mq_hctx_stopped(struct blk_mq_hw_ctx * hctx)180 static 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
blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx * hctx)185 static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
186 {
187 return hctx->nr_ctx && hctx->tags;
188 }
189
190 unsigned int blk_mq_in_flight(struct request_queue *q,
191 struct block_device *part);
192 void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part,
193 unsigned int inflight[2]);
194
blk_mq_put_dispatch_budget(struct request_queue * q,int budget_token)195 static inline void blk_mq_put_dispatch_budget(struct request_queue *q,
196 int budget_token)
197 {
198 if (q->mq_ops->put_budget)
199 q->mq_ops->put_budget(q, budget_token);
200 }
201
blk_mq_get_dispatch_budget(struct request_queue * q)202 static inline int blk_mq_get_dispatch_budget(struct request_queue *q)
203 {
204 if (q->mq_ops->get_budget)
205 return q->mq_ops->get_budget(q);
206 return 0;
207 }
208
blk_mq_set_rq_budget_token(struct request * rq,int token)209 static inline void blk_mq_set_rq_budget_token(struct request *rq, int token)
210 {
211 if (token < 0)
212 return;
213
214 if (rq->q->mq_ops->set_rq_budget_token)
215 rq->q->mq_ops->set_rq_budget_token(rq, token);
216 }
217
blk_mq_get_rq_budget_token(struct request * rq)218 static inline int blk_mq_get_rq_budget_token(struct request *rq)
219 {
220 if (rq->q->mq_ops->get_rq_budget_token)
221 return rq->q->mq_ops->get_rq_budget_token(rq);
222 return -1;
223 }
224
__blk_mq_inc_active_requests(struct blk_mq_hw_ctx * hctx)225 static inline void __blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx)
226 {
227 if (blk_mq_is_sbitmap_shared(hctx->flags))
228 atomic_inc(&hctx->queue->nr_active_requests_shared_sbitmap);
229 else
230 atomic_inc(&hctx->nr_active);
231 }
232
__blk_mq_dec_active_requests(struct blk_mq_hw_ctx * hctx)233 static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx)
234 {
235 if (blk_mq_is_sbitmap_shared(hctx->flags))
236 atomic_dec(&hctx->queue->nr_active_requests_shared_sbitmap);
237 else
238 atomic_dec(&hctx->nr_active);
239 }
240
__blk_mq_active_requests(struct blk_mq_hw_ctx * hctx)241 static inline int __blk_mq_active_requests(struct blk_mq_hw_ctx *hctx)
242 {
243 if (blk_mq_is_sbitmap_shared(hctx->flags))
244 return atomic_read(&hctx->queue->nr_active_requests_shared_sbitmap);
245 return atomic_read(&hctx->nr_active);
246 }
__blk_mq_put_driver_tag(struct blk_mq_hw_ctx * hctx,struct request * rq)247 static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
248 struct request *rq)
249 {
250 blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag);
251 rq->tag = BLK_MQ_NO_TAG;
252
253 if (rq->rq_flags & RQF_MQ_INFLIGHT) {
254 rq->rq_flags &= ~RQF_MQ_INFLIGHT;
255 __blk_mq_dec_active_requests(hctx);
256 }
257 }
258
blk_mq_put_driver_tag(struct request * rq)259 static inline void blk_mq_put_driver_tag(struct request *rq)
260 {
261 if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG)
262 return;
263
264 __blk_mq_put_driver_tag(rq->mq_hctx, rq);
265 }
266
267 bool blk_mq_get_driver_tag(struct request *rq);
268
blk_mq_clear_mq_map(struct blk_mq_queue_map * qmap)269 static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap)
270 {
271 int cpu;
272
273 for_each_possible_cpu(cpu)
274 qmap->mq_map[cpu] = 0;
275 }
276
277 /*
278 * blk_mq_plug() - Get caller context plug
279 * @q: request queue
280 * @bio : the bio being submitted by the caller context
281 *
282 * Plugging, by design, may delay the insertion of BIOs into the elevator in
283 * order to increase BIO merging opportunities. This however can cause BIO
284 * insertion order to change from the order in which submit_bio() is being
285 * executed in the case of multiple contexts concurrently issuing BIOs to a
286 * device, even if these context are synchronized to tightly control BIO issuing
287 * order. While this is not a problem with regular block devices, this ordering
288 * change can cause write BIO failures with zoned block devices as these
289 * require sequential write patterns to zones. Prevent this from happening by
290 * ignoring the plug state of a BIO issuing context if the target request queue
291 * is for a zoned block device and the BIO to plug is a write operation.
292 *
293 * Return current->plug if the bio can be plugged and NULL otherwise
294 */
blk_mq_plug(struct request_queue * q,struct bio * bio)295 static inline struct blk_plug *blk_mq_plug(struct request_queue *q,
296 struct bio *bio)
297 {
298 /*
299 * For regular block devices or read operations, use the context plug
300 * which may be NULL if blk_start_plug() was not executed.
301 */
302 if (!blk_queue_is_zoned(q) || !op_is_write(bio_op(bio)))
303 return current->plug;
304
305 /* Zoned block device write operation case: do not plug the BIO */
306 return NULL;
307 }
308
309 /* Free all requests on the list */
blk_mq_free_requests(struct list_head * list)310 static inline void blk_mq_free_requests(struct list_head *list)
311 {
312 while (!list_empty(list)) {
313 struct request *rq = list_entry_rq(list->next);
314
315 list_del_init(&rq->queuelist);
316 blk_mq_free_request(rq);
317 }
318 }
319
320 /*
321 * For shared tag users, we track the number of currently active users
322 * and attempt to provide a fair share of the tag depth for each of them.
323 */
hctx_may_queue(struct blk_mq_hw_ctx * hctx,struct sbitmap_queue * bt)324 static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx,
325 struct sbitmap_queue *bt)
326 {
327 unsigned int depth, users;
328
329 if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED))
330 return true;
331
332 /*
333 * Don't try dividing an ant
334 */
335 if (bt->sb.depth == 1)
336 return true;
337
338 if (blk_mq_is_sbitmap_shared(hctx->flags)) {
339 struct request_queue *q = hctx->queue;
340 struct blk_mq_tag_set *set = q->tag_set;
341
342 if (!test_bit(QUEUE_FLAG_HCTX_ACTIVE, &q->queue_flags))
343 return true;
344 users = atomic_read(&set->active_queues_shared_sbitmap);
345 } else {
346 if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state))
347 return true;
348 users = atomic_read(&hctx->tags->active_queues);
349 }
350
351 if (!users)
352 return true;
353
354 /*
355 * Allow at least some tags
356 */
357 depth = max((bt->sb.depth + users - 1) / users, 4U);
358 return __blk_mq_active_requests(hctx) < depth;
359 }
360
361
362 #endif
363