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 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 enum hctx_type type = HCTX_TYPE_DEFAULT; 93 94 /* 95 * The caller ensure that if REQ_POLLED, poll must be enabled. 96 */ 97 if (opf & REQ_POLLED) 98 type = HCTX_TYPE_POLL; 99 else if ((opf & REQ_OP_MASK) == REQ_OP_READ) 100 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 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 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 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 if (!hctx) 197 return &bt->ws[0]; 198 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 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) 207 __blk_mq_tag_busy(hctx); 208 } 209 210 static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx) 211 { 212 if (hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED) 213 __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 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 if (!(data->rq_flags & RQF_ELV)) 230 return data->hctx->tags; 231 return data->hctx->sched_tags; 232 } 233 234 static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx) 235 { 236 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 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 if (q->mq_ops->put_budget) 253 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 if (q->mq_ops->get_budget) 259 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 if (rq->q->mq_ops->set_rq_budget_token) 269 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 if (rq->q->mq_ops->get_rq_budget_token) 275 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 if (blk_mq_is_shared_tags(hctx->flags)) 282 atomic_inc(&hctx->queue->nr_active_requests_shared_tags); 283 else 284 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 if (blk_mq_is_shared_tags(hctx->flags)) 291 atomic_sub(val, &hctx->queue->nr_active_requests_shared_tags); 292 else 293 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 if (blk_mq_is_shared_tags(hctx->flags)) 304 return atomic_read(&hctx->queue->nr_active_requests_shared_tags); 305 return atomic_read(&hctx->nr_active); 306 } 307 static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, 308 struct request *rq) 309 { 310 blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag); 311 rq->tag = BLK_MQ_NO_TAG; 312 313 if (rq->rq_flags & RQF_MQ_INFLIGHT) { 314 rq->rq_flags &= ~RQF_MQ_INFLIGHT; 315 __blk_mq_dec_active_requests(hctx); 316 } 317 } 318 319 static inline void blk_mq_put_driver_tag(struct request *rq) 320 { 321 if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG) 322 return; 323 324 __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 static inline bool blk_mq_get_driver_tag(struct request *rq) 330 { 331 struct blk_mq_hw_ctx *hctx = rq->mq_hctx; 332 333 if (rq->tag != BLK_MQ_NO_TAG && 334 !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) { 335 hctx->tags->rqs[rq->tag] = rq; 336 return true; 337 } 338 339 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 for_each_possible_cpu(cpu) 347 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 return current->plug; 379 } 380 381 /* Free all requests on the list */ 382 static inline void blk_mq_free_requests(struct list_head *list) 383 { 384 while (!list_empty(list)) { 385 struct request *rq = list_entry_rq(list->next); 386 387 list_del_init(&rq->queuelist); 388 blk_mq_free_request(rq); 389 } 390 } 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 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 if (!hctx || !(hctx->flags & BLK_MQ_F_TAG_QUEUE_SHARED)) 402 return true; 403 404 /* 405 * Don't try dividing an ant 406 */ 407 if (bt->sb.depth == 1) 408 return true; 409 410 if (blk_mq_is_shared_tags(hctx->flags)) { 411 struct request_queue *q = hctx->queue; 412 413 if (!test_bit(QUEUE_FLAG_HCTX_ACTIVE, &q->queue_flags)) 414 return true; 415 } else { 416 if (!test_bit(BLK_MQ_S_TAG_ACTIVE, &hctx->state)) 417 return true; 418 } 419 420 users = atomic_read(&hctx->tags->active_queues); 421 422 if (!users) 423 return true; 424 425 /* 426 * Allow at least some tags 427 */ 428 depth = max((bt->sb.depth + users - 1) / users, 4U); 429 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 454