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