Line data Source code
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 : typedef unsigned int __bitwise blk_insert_t;
40 : #define BLK_MQ_INSERT_AT_HEAD ((__force blk_insert_t)0x01)
41 :
42 : void blk_mq_submit_bio(struct bio *bio);
43 : int blk_mq_poll(struct request_queue *q, blk_qc_t cookie, struct io_comp_batch *iob,
44 : unsigned int flags);
45 : void blk_mq_exit_queue(struct request_queue *q);
46 : int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
47 : void blk_mq_wake_waiters(struct request_queue *q);
48 : bool blk_mq_dispatch_rq_list(struct blk_mq_hw_ctx *hctx, struct list_head *,
49 : unsigned int);
50 : void blk_mq_add_to_requeue_list(struct request *rq, blk_insert_t insert_flags);
51 : void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
52 : struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
53 : struct blk_mq_ctx *start);
54 : void blk_mq_put_rq_ref(struct request *rq);
55 :
56 : /*
57 : * Internal helpers for allocating/freeing the request map
58 : */
59 : void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
60 : unsigned int hctx_idx);
61 : void blk_mq_free_rq_map(struct blk_mq_tags *tags);
62 : struct blk_mq_tags *blk_mq_alloc_map_and_rqs(struct blk_mq_tag_set *set,
63 : unsigned int hctx_idx, unsigned int depth);
64 : void blk_mq_free_map_and_rqs(struct blk_mq_tag_set *set,
65 : struct blk_mq_tags *tags,
66 : unsigned int hctx_idx);
67 : /*
68 : * Internal helpers for request insertion into sw queues
69 : */
70 : void blk_mq_request_bypass_insert(struct request *rq, blk_insert_t flags);
71 :
72 : /*
73 : * CPU -> queue mappings
74 : */
75 : extern int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int);
76 :
77 : /*
78 : * blk_mq_map_queue_type() - map (hctx_type,cpu) to hardware queue
79 : * @q: request queue
80 : * @type: the hctx type index
81 : * @cpu: CPU
82 : */
83 : static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q,
84 : enum hctx_type type,
85 : unsigned int cpu)
86 : {
87 0 : return xa_load(&q->hctx_table, q->tag_set->map[type].mq_map[cpu]);
88 : }
89 :
90 : static inline enum hctx_type blk_mq_get_hctx_type(blk_opf_t opf)
91 : {
92 0 : enum hctx_type type = HCTX_TYPE_DEFAULT;
93 :
94 : /*
95 : * The caller ensure that if REQ_POLLED, poll must be enabled.
96 : */
97 0 : if (opf & REQ_POLLED)
98 : type = HCTX_TYPE_POLL;
99 0 : else if ((opf & REQ_OP_MASK) == REQ_OP_READ)
100 0 : type = HCTX_TYPE_READ;
101 : return type;
102 : }
103 :
104 : /*
105 : * blk_mq_map_queue() - map (cmd_flags,type) to hardware queue
106 : * @q: request queue
107 : * @opf: operation type (REQ_OP_*) and flags (e.g. REQ_POLLED).
108 : * @ctx: software queue cpu ctx
109 : */
110 : static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
111 : blk_opf_t opf,
112 : struct blk_mq_ctx *ctx)
113 : {
114 0 : return ctx->hctxs[blk_mq_get_hctx_type(opf)];
115 : }
116 :
117 : /*
118 : * sysfs helpers
119 : */
120 : extern void blk_mq_sysfs_init(struct request_queue *q);
121 : extern void blk_mq_sysfs_deinit(struct request_queue *q);
122 : int blk_mq_sysfs_register(struct gendisk *disk);
123 : void blk_mq_sysfs_unregister(struct gendisk *disk);
124 : int blk_mq_sysfs_register_hctxs(struct request_queue *q);
125 : void blk_mq_sysfs_unregister_hctxs(struct request_queue *q);
126 : extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
127 : void blk_mq_free_plug_rqs(struct blk_plug *plug);
128 : void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule);
129 :
130 : void blk_mq_cancel_work_sync(struct request_queue *q);
131 :
132 : void blk_mq_release(struct request_queue *q);
133 :
134 : static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
135 : unsigned int cpu)
136 : {
137 0 : return per_cpu_ptr(q->queue_ctx, cpu);
138 : }
139 :
140 : /*
141 : * This assumes per-cpu software queueing queues. They could be per-node
142 : * as well, for instance. For now this is hardcoded as-is. Note that we don't
143 : * care about preemption, since we know the ctx's are persistent. This does
144 : * mean that we can't rely on ctx always matching the currently running CPU.
145 : */
146 : static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
147 : {
148 0 : return __blk_mq_get_ctx(q, raw_smp_processor_id());
149 : }
150 :
151 : struct blk_mq_alloc_data {
152 : /* input parameter */
153 : struct request_queue *q;
154 : blk_mq_req_flags_t flags;
155 : unsigned int shallow_depth;
156 : blk_opf_t cmd_flags;
157 : req_flags_t rq_flags;
158 :
159 : /* allocate multiple requests/tags in one go */
160 : unsigned int nr_tags;
161 : struct request **cached_rq;
162 :
163 : /* input & output parameter */
164 : struct blk_mq_ctx *ctx;
165 : struct blk_mq_hw_ctx *hctx;
166 : };
167 :
168 : struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags,
169 : unsigned int reserved_tags, int node, int alloc_policy);
170 : void blk_mq_free_tags(struct blk_mq_tags *tags);
171 : int blk_mq_init_bitmaps(struct sbitmap_queue *bitmap_tags,
172 : struct sbitmap_queue *breserved_tags, unsigned int queue_depth,
173 : unsigned int reserved, int node, int alloc_policy);
174 :
175 : unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data);
176 : unsigned long blk_mq_get_tags(struct blk_mq_alloc_data *data, int nr_tags,
177 : unsigned int *offset);
178 : void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx,
179 : unsigned int tag);
180 : void blk_mq_put_tags(struct blk_mq_tags *tags, int *tag_array, int nr_tags);
181 : int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
182 : struct blk_mq_tags **tags, unsigned int depth, bool can_grow);
183 : void blk_mq_tag_resize_shared_tags(struct blk_mq_tag_set *set,
184 : unsigned int size);
185 : void blk_mq_tag_update_sched_shared_tags(struct request_queue *q);
186 :
187 : void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool);
188 : void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_tag_iter_fn *fn,
189 : void *priv);
190 : void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn,
191 : void *priv);
192 :
193 : static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt,
194 : struct blk_mq_hw_ctx *hctx)
195 : {
196 0 : if (!hctx)
197 0 : return &bt->ws[0];
198 0 : return sbq_wait_ptr(bt, &hctx->wait_index);
199 : }
200 :
201 : void __blk_mq_tag_busy(struct blk_mq_hw_ctx *);
202 : void __blk_mq_tag_idle(struct blk_mq_hw_ctx *);
203 :
204 : static inline void blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx)
205 : {
206 0 : if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
207 0 : __blk_mq_tag_busy(hctx);
208 : }
209 :
210 : static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx)
211 : {
212 0 : if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)
213 0 : __blk_mq_tag_idle(hctx);
214 : }
215 :
216 : static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags,
217 : unsigned int tag)
218 : {
219 : return tag < tags->nr_reserved_tags;
220 : }
221 :
222 : static inline bool blk_mq_is_shared_tags(unsigned int flags)
223 : {
224 0 : return flags & BLK_MQ_F_TAG_HCTX_SHARED;
225 : }
226 :
227 : static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
228 : {
229 0 : if (!(data->rq_flags & RQF_ELV))
230 0 : return data->hctx->tags;
231 0 : return data->hctx->sched_tags;
232 : }
233 :
234 : static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
235 : {
236 0 : return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
237 : }
238 :
239 : static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
240 : {
241 0 : return hctx->nr_ctx && hctx->tags;
242 : }
243 :
244 : unsigned int blk_mq_in_flight(struct request_queue *q,
245 : struct block_device *part);
246 : void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part,
247 : unsigned int inflight[2]);
248 :
249 : static inline void blk_mq_put_dispatch_budget(struct request_queue *q,
250 : int budget_token)
251 : {
252 0 : if (q->mq_ops->put_budget)
253 0 : q->mq_ops->put_budget(q, budget_token);
254 : }
255 :
256 : static inline int blk_mq_get_dispatch_budget(struct request_queue *q)
257 : {
258 0 : if (q->mq_ops->get_budget)
259 0 : return q->mq_ops->get_budget(q);
260 : return 0;
261 : }
262 :
263 : static inline void blk_mq_set_rq_budget_token(struct request *rq, int token)
264 : {
265 : if (token < 0)
266 : return;
267 :
268 0 : if (rq->q->mq_ops->set_rq_budget_token)
269 0 : rq->q->mq_ops->set_rq_budget_token(rq, token);
270 : }
271 :
272 : static inline int blk_mq_get_rq_budget_token(struct request *rq)
273 : {
274 0 : if (rq->q->mq_ops->get_rq_budget_token)
275 0 : return rq->q->mq_ops->get_rq_budget_token(rq);
276 : return -1;
277 : }
278 :
279 : static inline void __blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx)
280 : {
281 0 : if (blk_mq_is_shared_tags(hctx->flags))
282 0 : atomic_inc(&hctx->queue->nr_active_requests_shared_tags);
283 : else
284 0 : atomic_inc(&hctx->nr_active);
285 : }
286 :
287 : static inline void __blk_mq_sub_active_requests(struct blk_mq_hw_ctx *hctx,
288 : int val)
289 : {
290 0 : if (blk_mq_is_shared_tags(hctx->flags))
291 0 : atomic_sub(val, &hctx->queue->nr_active_requests_shared_tags);
292 : else
293 0 : atomic_sub(val, &hctx->nr_active);
294 : }
295 :
296 : static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx)
297 : {
298 : __blk_mq_sub_active_requests(hctx, 1);
299 : }
300 :
301 : static inline int __blk_mq_active_requests(struct blk_mq_hw_ctx *hctx)
302 : {
303 0 : if (blk_mq_is_shared_tags(hctx->flags))
304 0 : return atomic_read(&hctx->queue->nr_active_requests_shared_tags);
305 0 : return atomic_read(&hctx->nr_active);
306 : }
307 0 : static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
308 : struct request *rq)
309 : {
310 0 : blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag);
311 0 : rq->tag = BLK_MQ_NO_TAG;
312 :
313 0 : if (rq->rq_flags & RQF_MQ_INFLIGHT) {
314 0 : rq->rq_flags &= ~RQF_MQ_INFLIGHT;
315 : __blk_mq_dec_active_requests(hctx);
316 : }
317 0 : }
318 :
319 : static inline void blk_mq_put_driver_tag(struct request *rq)
320 : {
321 0 : if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG)
322 : return;
323 :
324 0 : __blk_mq_put_driver_tag(rq->mq_hctx, rq);
325 : }
326 :
327 : bool __blk_mq_get_driver_tag(struct blk_mq_hw_ctx *hctx, struct request *rq);
328 :
329 0 : static inline bool blk_mq_get_driver_tag(struct request *rq)
330 : {
331 0 : struct blk_mq_hw_ctx *hctx = rq->mq_hctx;
332 :
333 0 : if (rq->tag != BLK_MQ_NO_TAG &&
334 0 : !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) {
335 0 : hctx->tags->rqs[rq->tag] = rq;
336 0 : return true;
337 : }
338 :
339 0 : return __blk_mq_get_driver_tag(hctx, rq);
340 : }
341 :
342 : static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap)
343 : {
344 : int cpu;
345 :
346 0 : for_each_possible_cpu(cpu)
347 0 : qmap->mq_map[cpu] = 0;
348 : }
349 :
350 : /*
351 : * blk_mq_plug() - Get caller context plug
352 : * @bio : the bio being submitted by the caller context
353 : *
354 : * Plugging, by design, may delay the insertion of BIOs into the elevator in
355 : * order to increase BIO merging opportunities. This however can cause BIO
356 : * insertion order to change from the order in which submit_bio() is being
357 : * executed in the case of multiple contexts concurrently issuing BIOs to a
358 : * device, even if these context are synchronized to tightly control BIO issuing
359 : * order. While this is not a problem with regular block devices, this ordering
360 : * change can cause write BIO failures with zoned block devices as these
361 : * require sequential write patterns to zones. Prevent this from happening by
362 : * ignoring the plug state of a BIO issuing context if it is for a zoned block
363 : * device and the BIO to plug is a write operation.
364 : *
365 : * Return current->plug if the bio can be plugged and NULL otherwise
366 : */
367 : static inline struct blk_plug *blk_mq_plug( struct bio *bio)
368 : {
369 : /* Zoned block device write operation case: do not plug the BIO */
370 : if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
371 : bdev_op_is_zoned_write(bio->bi_bdev, bio_op(bio)))
372 : return NULL;
373 :
374 : /*
375 : * For regular block devices or read operations, use the context plug
376 : * which may be NULL if blk_start_plug() was not executed.
377 : */
378 0 : return current->plug;
379 : }
380 :
381 : /* Free all requests on the list */
382 0 : static inline void blk_mq_free_requests(struct list_head *list)
383 : {
384 0 : while (!list_empty(list)) {
385 0 : struct request *rq = list_entry_rq(list->next);
386 :
387 0 : list_del_init(&rq->queuelist);
388 0 : blk_mq_free_request(rq);
389 : }
390 0 : }
391 :
392 : /*
393 : * For shared tag users, we track the number of currently active users
394 : * and attempt to provide a fair share of the tag depth for each of them.
395 : */
396 0 : static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx,
397 : struct sbitmap_queue *bt)
398 : {
399 : unsigned int depth, users;
400 :
401 0 : if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED))
402 : return true;
403 :
404 : /*
405 : * Don't try dividing an ant
406 : */
407 0 : if (bt->sb.depth == 1)
408 : return true;
409 :
410 0 : if (blk_mq_is_shared_tags(hctx->flags)) {
411 0 : struct request_queue *q = hctx->queue;
412 :
413 0 : if (!test_bit(QUEUE_FLAG_HCTX_ACTIVE, &q->queue_flags))
414 : return true;
415 : } else {
416 0 : if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state))
417 : return true;
418 : }
419 :
420 0 : users = atomic_read(&hctx->tags->active_queues);
421 :
422 0 : if (!users)
423 : return true;
424 :
425 : /*
426 : * Allow at least some tags
427 : */
428 0 : depth = max((bt->sb.depth + users - 1) / users, 4U);
429 0 : return __blk_mq_active_requests(hctx) < depth;
430 : }
431 :
432 : /* run the code block in @dispatch_ops with rcu/srcu read lock held */
433 : #define __blk_mq_run_dispatch_ops(q, check_sleep, dispatch_ops) \
434 : do { \
435 : if ((q)->tag_set->flags & BLK_MQ_F_BLOCKING) { \
436 : struct blk_mq_tag_set *__tag_set = (q)->tag_set; \
437 : int srcu_idx; \
438 : \
439 : might_sleep_if(check_sleep); \
440 : srcu_idx = srcu_read_lock(__tag_set->srcu); \
441 : (dispatch_ops); \
442 : srcu_read_unlock(__tag_set->srcu, srcu_idx); \
443 : } else { \
444 : rcu_read_lock(); \
445 : (dispatch_ops); \
446 : rcu_read_unlock(); \
447 : } \
448 : } while (0)
449 :
450 : #define blk_mq_run_dispatch_ops(q, dispatch_ops) \
451 : __blk_mq_run_dispatch_ops(q, true, dispatch_ops) \
452 :
453 : #endif
|
