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_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list); 51 struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx, 52 struct blk_mq_ctx *start); 53 void blk_mq_put_rq_ref(struct request *rq); 54 55 /* 56 * Internal helpers for allocating/freeing the request map 57 */ 58 void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, 59 unsigned int hctx_idx); 60 void blk_mq_free_rq_map(struct blk_mq_tags *tags); 61 struct blk_mq_tags *blk_mq_alloc_map_and_rqs(struct blk_mq_tag_set *set, 62 unsigned int hctx_idx, unsigned int depth); 63 void blk_mq_free_map_and_rqs(struct blk_mq_tag_set *set, 64 struct blk_mq_tags *tags, 65 unsigned int hctx_idx); 66 67 /* 68 * CPU -> queue mappings 69 */ 70 extern int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int); 71 72 /* 73 * blk_mq_map_queue_type() - map (hctx_type,cpu) to hardware queue 74 * @q: request queue 75 * @type: the hctx type index 76 * @cpu: CPU 77 */ 78 static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q, 79 enum hctx_type type, 80 unsigned int cpu) 81 { 82 return xa_load(&q->hctx_table, q->tag_set->map[type].mq_map[cpu]); 83 } 84 85 static inline enum hctx_type blk_mq_get_hctx_type(blk_opf_t opf) 86 { 87 enum hctx_type type = HCTX_TYPE_DEFAULT; 88 89 /* 90 * The caller ensure that if REQ_POLLED, poll must be enabled. 91 */ 92 if (opf & REQ_POLLED) 93 type = HCTX_TYPE_POLL; 94 else if ((opf & REQ_OP_MASK) == REQ_OP_READ) 95 type = HCTX_TYPE_READ; 96 return type; 97 } 98 99 /* 100 * blk_mq_map_queue() - map (cmd_flags,type) to hardware queue 101 * @q: request queue 102 * @opf: operation type (REQ_OP_*) and flags (e.g. REQ_POLLED). 103 * @ctx: software queue cpu ctx 104 */ 105 static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, 106 blk_opf_t opf, 107 struct blk_mq_ctx *ctx) 108 { 109 return ctx->hctxs[blk_mq_get_hctx_type(opf)]; 110 } 111 112 /* 113 * sysfs helpers 114 */ 115 extern void blk_mq_sysfs_init(struct request_queue *q); 116 extern void blk_mq_sysfs_deinit(struct request_queue *q); 117 int blk_mq_sysfs_register(struct gendisk *disk); 118 void blk_mq_sysfs_unregister(struct gendisk *disk); 119 int blk_mq_sysfs_register_hctxs(struct request_queue *q); 120 void blk_mq_sysfs_unregister_hctxs(struct request_queue *q); 121 extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx); 122 void blk_mq_free_plug_rqs(struct blk_plug *plug); 123 void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule); 124 125 void blk_mq_cancel_work_sync(struct request_queue *q); 126 127 void blk_mq_release(struct request_queue *q); 128 129 static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q, 130 unsigned int cpu) 131 { 132 return per_cpu_ptr(q->queue_ctx, cpu); 133 } 134 135 /* 136 * This assumes per-cpu software queueing queues. They could be per-node 137 * as well, for instance. For now this is hardcoded as-is. Note that we don't 138 * care about preemption, since we know the ctx's are persistent. This does 139 * mean that we can't rely on ctx always matching the currently running CPU. 140 */ 141 static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q) 142 { 143 return __blk_mq_get_ctx(q, raw_smp_processor_id()); 144 } 145 146 struct blk_mq_alloc_data { 147 /* input parameter */ 148 struct request_queue *q; 149 blk_mq_req_flags_t flags; 150 unsigned int shallow_depth; 151 blk_opf_t cmd_flags; 152 req_flags_t rq_flags; 153 154 /* allocate multiple requests/tags in one go */ 155 unsigned int nr_tags; 156 struct request **cached_rq; 157 158 /* input & output parameter */ 159 struct blk_mq_ctx *ctx; 160 struct blk_mq_hw_ctx *hctx; 161 }; 162 163 struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags, 164 unsigned int reserved_tags, int node, int alloc_policy); 165 void blk_mq_free_tags(struct blk_mq_tags *tags); 166 int blk_mq_init_bitmaps(struct sbitmap_queue *bitmap_tags, 167 struct sbitmap_queue *breserved_tags, unsigned int queue_depth, 168 unsigned int reserved, int node, int alloc_policy); 169 170 unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data); 171 unsigned long blk_mq_get_tags(struct blk_mq_alloc_data *data, int nr_tags, 172 unsigned int *offset); 173 void blk_mq_put_tag(struct blk_mq_tags *tags, struct blk_mq_ctx *ctx, 174 unsigned int tag); 175 void blk_mq_put_tags(struct blk_mq_tags *tags, int *tag_array, int nr_tags); 176 int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx, 177 struct blk_mq_tags **tags, unsigned int depth, bool can_grow); 178 void blk_mq_tag_resize_shared_tags(struct blk_mq_tag_set *set, 179 unsigned int size); 180 void blk_mq_tag_update_sched_shared_tags(struct request_queue *q); 181 182 void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool); 183 void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_tag_iter_fn *fn, 184 void *priv); 185 void blk_mq_all_tag_iter(struct blk_mq_tags *tags, busy_tag_iter_fn *fn, 186 void *priv); 187 188 static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt, 189 struct blk_mq_hw_ctx *hctx) 190 { 191 if (!hctx) 192 return &bt->ws[0]; 193 return sbq_wait_ptr(bt, &hctx->wait_index); 194 } 195 196 void __blk_mq_tag_busy(struct blk_mq_hw_ctx *); 197 void __blk_mq_tag_idle(struct blk_mq_hw_ctx *); 198 199 static inline void blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx) 200 { 201 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) 202 __blk_mq_tag_busy(hctx); 203 } 204 205 static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) 206 { 207 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) 208 __blk_mq_tag_idle(hctx); 209 } 210 211 static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags, 212 unsigned int tag) 213 { 214 return tag < tags->nr_reserved_tags; 215 } 216 217 static inline bool blk_mq_is_shared_tags(unsigned int flags) 218 { 219 return flags & BLK_MQ_F_TAG_HCTX_SHARED; 220 } 221 222 static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data) 223 { 224 if (data->rq_flags & RQF_SCHED_TAGS) 225 return data->hctx->sched_tags; 226 return data->hctx->tags; 227 } 228 229 static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx) 230 { 231 return test_bit(BLK_MQ_S_STOPPED, &hctx->state); 232 } 233 234 static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx) 235 { 236 return hctx->nr_ctx && hctx->tags; 237 } 238 239 unsigned int blk_mq_in_flight(struct request_queue *q, 240 struct block_device *part); 241 void blk_mq_in_flight_rw(struct request_queue *q, struct block_device *part, 242 unsigned int inflight[2]); 243 244 static inline void blk_mq_put_dispatch_budget(struct request_queue *q, 245 int budget_token) 246 { 247 if (q->mq_ops->put_budget) 248 q->mq_ops->put_budget(q, budget_token); 249 } 250 251 static inline int blk_mq_get_dispatch_budget(struct request_queue *q) 252 { 253 if (q->mq_ops->get_budget) 254 return q->mq_ops->get_budget(q); 255 return 0; 256 } 257 258 static inline void blk_mq_set_rq_budget_token(struct request *rq, int token) 259 { 260 if (token < 0) 261 return; 262 263 if (rq->q->mq_ops->set_rq_budget_token) 264 rq->q->mq_ops->set_rq_budget_token(rq, token); 265 } 266 267 static inline int blk_mq_get_rq_budget_token(struct request *rq) 268 { 269 if (rq->q->mq_ops->get_rq_budget_token) 270 return rq->q->mq_ops->get_rq_budget_token(rq); 271 return -1; 272 } 273 274 static inline void __blk_mq_add_active_requests(struct blk_mq_hw_ctx *hctx, 275 int val) 276 { 277 if (blk_mq_is_shared_tags(hctx->flags)) 278 atomic_add(val, &hctx->queue->nr_active_requests_shared_tags); 279 else 280 atomic_add(val, &hctx->nr_active); 281 } 282 283 static inline void __blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx) 284 { 285 __blk_mq_add_active_requests(hctx, 1); 286 } 287 288 static inline void __blk_mq_sub_active_requests(struct blk_mq_hw_ctx *hctx, 289 int val) 290 { 291 if (blk_mq_is_shared_tags(hctx->flags)) 292 atomic_sub(val, &hctx->queue->nr_active_requests_shared_tags); 293 else 294 atomic_sub(val, &hctx->nr_active); 295 } 296 297 static inline void __blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx) 298 { 299 __blk_mq_sub_active_requests(hctx, 1); 300 } 301 302 static inline void blk_mq_add_active_requests(struct blk_mq_hw_ctx *hctx, 303 int val) 304 { 305 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) 306 __blk_mq_add_active_requests(hctx, val); 307 } 308 309 static inline void blk_mq_inc_active_requests(struct blk_mq_hw_ctx *hctx) 310 { 311 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) 312 __blk_mq_inc_active_requests(hctx); 313 } 314 315 static inline void blk_mq_sub_active_requests(struct blk_mq_hw_ctx *hctx, 316 int val) 317 { 318 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) 319 __blk_mq_sub_active_requests(hctx, val); 320 } 321 322 static inline void blk_mq_dec_active_requests(struct blk_mq_hw_ctx *hctx) 323 { 324 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) 325 __blk_mq_dec_active_requests(hctx); 326 } 327 328 static inline int __blk_mq_active_requests(struct blk_mq_hw_ctx *hctx) 329 { 330 if (blk_mq_is_shared_tags(hctx->flags)) 331 return atomic_read(&hctx->queue->nr_active_requests_shared_tags); 332 return atomic_read(&hctx->nr_active); 333 } 334 static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, 335 struct request *rq) 336 { 337 blk_mq_dec_active_requests(hctx); 338 blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag); 339 rq->tag = BLK_MQ_NO_TAG; 340 } 341 342 static inline void blk_mq_put_driver_tag(struct request *rq) 343 { 344 if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG) 345 return; 346 347 __blk_mq_put_driver_tag(rq->mq_hctx, rq); 348 } 349 350 bool __blk_mq_alloc_driver_tag(struct request *rq); 351 352 static inline bool blk_mq_get_driver_tag(struct request *rq) 353 { 354 if (rq->tag == BLK_MQ_NO_TAG && !__blk_mq_alloc_driver_tag(rq)) 355 return false; 356 357 return true; 358 } 359 360 static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap) 361 { 362 int cpu; 363 364 for_each_possible_cpu(cpu) 365 qmap->mq_map[cpu] = 0; 366 } 367 368 /* 369 * blk_mq_plug() - Get caller context plug 370 * @bio : the bio being submitted by the caller context 371 * 372 * Plugging, by design, may delay the insertion of BIOs into the elevator in 373 * order to increase BIO merging opportunities. This however can cause BIO 374 * insertion order to change from the order in which submit_bio() is being 375 * executed in the case of multiple contexts concurrently issuing BIOs to a 376 * device, even if these context are synchronized to tightly control BIO issuing 377 * order. While this is not a problem with regular block devices, this ordering 378 * change can cause write BIO failures with zoned block devices as these 379 * require sequential write patterns to zones. Prevent this from happening by 380 * ignoring the plug state of a BIO issuing context if it is for a zoned block 381 * device and the BIO to plug is a write operation. 382 * 383 * Return current->plug if the bio can be plugged and NULL otherwise 384 */ 385 static inline struct blk_plug *blk_mq_plug( struct bio *bio) 386 { 387 /* Zoned block device write operation case: do not plug the BIO */ 388 if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) && 389 bdev_op_is_zoned_write(bio->bi_bdev, bio_op(bio))) 390 return NULL; 391 392 /* 393 * For regular block devices or read operations, use the context plug 394 * which may be NULL if blk_start_plug() was not executed. 395 */ 396 return current->plug; 397 } 398 399 /* Free all requests on the list */ 400 static inline void blk_mq_free_requests(struct list_head *list) 401 { 402 while (!list_empty(list)) { 403 struct request *rq = list_entry_rq(list->next); 404 405 list_del_init(&rq->queuelist); 406 blk_mq_free_request(rq); 407 } 408 } 409 410 /* 411 * For shared tag users, we track the number of currently active users 412 * and attempt to provide a fair share of the tag depth for each of them. 413 */ 414 static inline bool hctx_may_queue(struct blk_mq_hw_ctx *hctx, 415 struct sbitmap_queue *bt) 416 { 417 unsigned int depth, users; 418 419 if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) 420 return true; 421 422 /* 423 * Don't try dividing an ant 424 */ 425 if (bt->sb.depth == 1) 426 return true; 427 428 if (blk_mq_is_shared_tags(hctx->flags)) { 429 struct request_queue *q = hctx->queue; 430 431 if (!test_bit(QUEUE_FLAG_HCTX_ACTIVE, &q->queue_flags)) 432 return true; 433 } else { 434 if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) 435 return true; 436 } 437 438 users = READ_ONCE(hctx->tags->active_queues); 439 if (!users) 440 return true; 441 442 /* 443 * Allow at least some tags 444 */ 445 depth = max((bt->sb.depth + users - 1) / users, 4U); 446 return __blk_mq_active_requests(hctx) < depth; 447 } 448 449 /* run the code block in @dispatch_ops with rcu/srcu read lock held */ 450 #define __blk_mq_run_dispatch_ops(q, check_sleep, dispatch_ops) \ 451 do { \ 452 if ((q)->tag_set->flags & BLK_MQ_F_BLOCKING) { \ 453 struct blk_mq_tag_set *__tag_set = (q)->tag_set; \ 454 int srcu_idx; \ 455 \ 456 might_sleep_if(check_sleep); \ 457 srcu_idx = srcu_read_lock(__tag_set->srcu); \ 458 (dispatch_ops); \ 459 srcu_read_unlock(__tag_set->srcu, srcu_idx); \ 460 } else { \ 461 rcu_read_lock(); \ 462 (dispatch_ops); \ 463 rcu_read_unlock(); \ 464 } \ 465 } while (0) 466 467 #define blk_mq_run_dispatch_ops(q, dispatch_ops) \ 468 __blk_mq_run_dispatch_ops(q, true, dispatch_ops) \ 469 470 #endif 471