1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef INT_BLK_MQ_H
3 #define INT_BLK_MQ_H
4
5 #include <linux/blk-mq.h>
6 #include "blk-stat.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 struct request_queue *queue;
29 struct blk_mq_ctxs *ctxs;
30 struct kobject kobj;
31 } ____cacheline_aligned_in_smp;
32
33 enum {
34 BLK_MQ_NO_TAG = -1U,
35 BLK_MQ_TAG_MIN = 1,
36 BLK_MQ_TAG_MAX = BLK_MQ_NO_TAG - 1,
37 };
38
39 #define BLK_MQ_CPU_WORK_BATCH (8)
40
41 typedef unsigned int __bitwise blk_insert_t;
42 #define BLK_MQ_INSERT_AT_HEAD ((__force blk_insert_t)0x01)
43
44 void blk_mq_submit_bio(struct bio *bio);
45 int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, struct io_comp_batch *iob,
46 unsigned int flags);
47 void blk_mq_exit_queue(struct request_queue *q);
48 int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
49 void blk_mq_wake_waiters(struct request_queue *q);
50 bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *,
51 unsigned int);
52 void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
53 struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
54 struct blk_mq_ctx *start);
55 void blk_mq_put_rq_ref(struct request *rq);
56
57 /*
58 * Internal helpers for allocating/freeing the request map
59 */
60 void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
61 unsigned int hctx_idx);
62 void blk_mq_free_rq_map(struct blk_mq_tags *tags);
63 struct blk_mq_tags *blk_mq_alloc_map_and_rqs(struct blk_mq_tag_set *set,
64 unsigned int hctx_idx, unsigned int depth);
65 void blk_mq_free_map_and_rqs(struct blk_mq_tag_set *set,
66 struct blk_mq_tags *tags,
67 unsigned int hctx_idx);
68
69 /*
70 * CPU -> queue mappings
71 */
72 extern int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int);
73
74 /*
75 * blk_mq_map_queue_type() - map (hctx_type,cpu) to hardware queue
76 * @q: request queue
77 * @type: the hctx type index
78 * @cpu: CPU
79 */
80 static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q,
81 enum hctx_type type,
82 unsigned int cpu)
83 {
84 return xa_load(&q->hctx_table, q->tag_set->map[type].mq_map[cpu]);
85 }
86
87 static inline enum hctx_type blk_mq_get_hctx_type(blk_opf_t opf)
88 {
89 enum hctx_type type = HCTX_TYPE_DEFAULT;
90
91 /*
92 * The caller ensure that if REQ_POLLED, poll must be enabled.
93 */
94 if (opf & REQ_POLLED)
95 type = HCTX_TYPE_POLL;
96 else if ((opf & REQ_OP_MASK) == REQ_OP_READ)
97 type = HCTX_TYPE_READ;
98 return type;
99 }
100
101 /*
102 * blk_mq_map_queue() - map (cmd_flags,type) to hardware queue
103 * @q: request queue
104 * @opf: operation type (REQ_OP_*) and flags (e.g. REQ_POLLED).
105 * @ctx: software queue cpu ctx
106 */
107 static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
108 blk_opf_t opf,
109 struct blk_mq_ctx *ctx)
110 {
111 return ctx->hctxs[blk_mq_get_hctx_type(opf)];
112 }
113
114 /*
115 * sysfs helpers
116 */
117 extern void blk_mq_sysfs_init(struct request_queue *q);
118 extern void blk_mq_sysfs_deinit(struct request_queue *q);
119 int blk_mq_sysfs_register(struct gendisk *disk);
120 void blk_mq_sysfs_unregister(struct gendisk *disk);
121 int blk_mq_sysfs_register_hctxs(struct request_queue *q);
122 void blk_mq_sysfs_unregister_hctxs(struct request_queue *q);
123 extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
124 void blk_mq_free_plug_rqs(struct blk_plug *plug);
125 void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule);
126
127 void blk_mq_cancel_work_sync(struct request_queue *q);
128
129 void blk_mq_release(struct request_queue *q);
130
131 static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
132 unsigned int cpu)
133 {
134 return per_cpu_ptr(q->queue_ctx, cpu);
135 }
136
137 /*
138 * This assumes per-cpu software queueing queues. They could be per-node
139 * as well, for instance. For now this is hardcoded as-is. Note that we don't
140 * care about preemption, since we know the ctx's are persistent. This does
141 * mean that we can't rely on ctx always matching the currently running CPU.
142 */
143 static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
144 {
145 return __blk_mq_get_ctx(q, raw_smp_processor_id());
146 }
147
148 struct blk_mq_alloc_data {
149 /* input parameter */
150 struct request_queue *q;
151 blk_mq_req_flags_t flags;
152 unsigned int shallow_depth;
153 blk_opf_t cmd_flags;
154 req_flags_t rq_flags;
155
156 /* allocate multiple requests/tags in one go */
157 unsigned int nr_tags;
158 struct request **cached_rq;
159
160 /* input & output parameter */
161 struct blk_mq_ctx *ctx;
162 struct blk_mq_hw_ctx *hctx;
163 };
164
165 struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags,
166 unsigned int reserved_tags, int node, int alloc_policy);
167 void blk_mq_free_tags(struct blk_mq_tags *tags);
168 int blk_mq_init_bitmaps(struct sbitmap_queue *bitmap_tags,
169 struct sbitmap_queue *breserved_tags, unsigned int queue_depth,
170 unsigned int reserved, int node, int alloc_policy);
171
172 unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data);
173 unsigned long blk_mq_get_tags(struct blk_mq_alloc_data *data, int nr_tags,
174 unsigned int *offset);
175 void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx,
176 unsigned int tag);
177 void blk_mq_put_tags(struct blk_mq_tags *tags, int *tag_array, int nr_tags);
178 int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
179 struct blk_mq_tags **tags, unsigned int depth, bool can_grow);
180 void blk_mq_tag_resize_shared_tags(struct blk_mq_tag_set *set,
181 unsigned int size);
182 void blk_mq_tag_update_sched_shared_tags(struct request_queue *q);
183
184 void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool);
185 void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_tag_iter_fn *fn,
186 void *priv);
187 void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn,
188 void *priv);
189
190 static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt,
191 struct blk_mq_hw_ctx *hctx)
192 {
193 if (!hctx)
194 return &bt->ws[0];
195 return sbq_wait_ptr(bt, &hctx->wait_index);
196 }
197
198 void __blk_mq_tag_busy(struct blk_mq_hw_ctx *);
199 void __blk_mq_tag_idle(struct blk_mq_hw_ctx *);
200
201 static inline void blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx)
202 {
203 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
204 __blk_mq_tag_busy(hctx);
205 }
206
207 static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx)
208 {
209 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
210 __blk_mq_tag_idle(hctx);
211 }
212
213 static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags,
214 unsigned int tag)
215 {
216 return tag < tags->nr_reserved_tags;
217 }
218
219 static inline bool blk_mq_is_shared_tags(unsigned int flags)
220 {
221 return flags & BLK_MQ_F_TAG_HCTX_SHARED;
222 }
223
224 static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
225 {
226 if (data->rq_flags & RQF_SCHED_TAGS)
227 return data->hctx->sched_tags;
228 return data->hctx->tags;
229 }
230
231 static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
232 {
233 return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
234 }
235
236 static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
237 {
238 return hctx->nr_ctx && hctx->tags;
239 }
240
241 unsigned int blk_mq_in_flight(struct request_queue *q,
242 struct block_device *part);
243 void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part,
244 unsigned int inflight[2]);
245
246 static inline void blk_mq_put_dispatch_budget(struct request_queue *q,
247 int budget_token)
248 {
249 if (q->mq_ops->put_budget)
250 q->mq_ops->put_budget(q, budget_token);
251 }
252
253 static inline int blk_mq_get_dispatch_budget(struct request_queue *q)
254 {
255 if (q->mq_ops->get_budget)
256 return q->mq_ops->get_budget(q);
257 return 0;
258 }
259
260 static inline void blk_mq_set_rq_budget_token(struct request *rq, int token)
261 {
262 if (token < 0)
263 return;
264
265 if (rq->q->mq_ops->set_rq_budget_token)
266 rq->q->mq_ops->set_rq_budget_token(rq, token);
267 }
268
269 static inline int blk_mq_get_rq_budget_token(struct request *rq)
270 {
271 if (rq->q->mq_ops->get_rq_budget_token)
272 return rq->q->mq_ops->get_rq_budget_token(rq);
273 return -1;
274 }
275
276 static inline void __blk_mq_add_active_requests(struct blk_mq_hw_ctx *hctx,
277 int val)
278 {
279 if (blk_mq_is_shared_tags(hctx->flags))
280 atomic_add(val, &hctx->queue->nr_active_requests_shared_tags);
281 else
282 atomic_add(val, &hctx->nr_active);
283 }
284
285 static inline void __blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx)
286 {
287 __blk_mq_add_active_requests(hctx, 1);
288 }
289
290 static inline void __blk_mq_sub_active_requests(struct blk_mq_hw_ctx *hctx,
291 int val)
292 {
293 if (blk_mq_is_shared_tags(hctx->flags))
294 atomic_sub(val, &hctx->queue->nr_active_requests_shared_tags);
295 else
296 atomic_sub(val, &hctx->nr_active);
297 }
298
299 static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx)
300 {
301 __blk_mq_sub_active_requests(hctx, 1);
302 }
303
304 static inline void blk_mq_add_active_requests(struct blk_mq_hw_ctx *hctx,
305 int val)
306 {
307 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
308 __blk_mq_add_active_requests(hctx, val);
309 }
310
311 static inline void blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx)
312 {
313 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
314 __blk_mq_inc_active_requests(hctx);
315 }
316
317 static inline void blk_mq_sub_active_requests(struct blk_mq_hw_ctx *hctx,
318 int val)
319 {
320 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
321 __blk_mq_sub_active_requests(hctx, val);
322 }
323
324 static inline void blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx)
325 {
326 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
327 __blk_mq_dec_active_requests(hctx);
328 }
329
330 static inline int __blk_mq_active_requests(struct blk_mq_hw_ctx *hctx)
331 {
332 if (blk_mq_is_shared_tags(hctx->flags))
333 return atomic_read(&hctx->queue->nr_active_requests_shared_tags);
334 return atomic_read(&hctx->nr_active);
335 }
336 static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
337 struct request *rq)
338 {
339 blk_mq_dec_active_requests(hctx);
340 blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag);
341 rq->tag = BLK_MQ_NO_TAG;
342 }
343
344 static inline void blk_mq_put_driver_tag(struct request *rq)
345 {
346 if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG)
347 return;
348
349 __blk_mq_put_driver_tag(rq->mq_hctx, rq);
350 }
351
352 bool __blk_mq_alloc_driver_tag(struct request *rq);
353
354 static inline bool blk_mq_get_driver_tag(struct request *rq)
355 {
356 if (rq->tag == BLK_MQ_NO_TAG && !__blk_mq_alloc_driver_tag(rq))
357 return false;
358
359 return true;
360 }
361
362 static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap)
363 {
364 int cpu;
365
366 for_each_possible_cpu(cpu)
367 qmap->mq_map[cpu] = 0;
368 }
369
370 /* Free all requests on the list */
371 static inline void blk_mq_free_requests(struct list_head *list)
372 {
373 while (!list_empty(list)) {
374 struct request *rq = list_entry_rq(list->next);
375
376 list_del_init(&rq->queuelist);
377 blk_mq_free_request(rq);
378 }
379 }
380
381 /*
382 * For shared tag users, we track the number of currently active users
383 * and attempt to provide a fair share of the tag depth for each of them.
384 */
385 static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx,
386 struct sbitmap_queue *bt)
387 {
388 unsigned int depth, users;
389
390 if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED))
391 return true;
392
393 /*
394 * Don't try dividing an ant
395 */
396 if (bt->sb.depth == 1)
397 return true;
398
399 if (blk_mq_is_shared_tags(hctx->flags)) {
400 struct request_queue *q = hctx->queue;
401
402 if (!test_bit(QUEUE_FLAG_HCTX_ACTIVE, &q->queue_flags))
403 return true;
404 } else {
405 if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state))
406 return true;
407 }
408
409 users = READ_ONCE(hctx->tags->active_queues);
410 if (!users)
411 return true;
412
413 /*
414 * Allow at least some tags
415 */
416 depth = max((bt->sb.depth + users - 1) / users, 4U);
417 return __blk_mq_active_requests(hctx) < depth;
418 }
419
420 /* run the code block in @dispatch_ops with rcu/srcu read lock held */
421 #define __blk_mq_run_dispatch_ops(q, check_sleep, dispatch_ops) \
422 do { \
423 if ((q)->tag_set->flags & BLK_MQ_F_BLOCKING) { \
424 struct blk_mq_tag_set *__tag_set = (q)->tag_set; \
425 int srcu_idx; \
426 \
427 might_sleep_if(check_sleep); \
428 srcu_idx = srcu_read_lock(__tag_set->srcu); \
429 (dispatch_ops); \
430 srcu_read_unlock(__tag_set->srcu, srcu_idx); \
431 } else { \
432 rcu_read_lock(); \
433 (dispatch_ops); \
434 rcu_read_unlock(); \
435 } \
436 } while (0)
437
438 #define blk_mq_run_dispatch_ops(q, dispatch_ops) \
439 __blk_mq_run_dispatch_ops(q, true, dispatch_ops) \
440
441 #endif
442
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.