1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef BLK_INTERNAL_H 3 #define BLK_INTERNAL_H 4 5 #include <linux/idr.h> 6 #include <linux/blk-mq.h> 7 #include "blk-mq.h" 8 9 /* Amount of time in which a process may batch requests */ 10 #define BLK_BATCH_TIME (HZ/50UL) 11 12 /* Number of requests a "batching" process may submit */ 13 #define BLK_BATCH_REQ 32 14 15 /* Max future timer expiry for timeouts */ 16 #define BLK_MAX_TIMEOUT (5 * HZ) 17 18 #ifdef CONFIG_DEBUG_FS 19 extern struct dentry *blk_debugfs_root; 20 #endif 21 22 struct blk_flush_queue { 23 unsigned int flush_queue_delayed:1; 24 unsigned int flush_pending_idx:1; 25 unsigned int flush_running_idx:1; 26 unsigned long flush_pending_since; 27 struct list_head flush_queue[2]; 28 struct list_head flush_data_in_flight; 29 struct request *flush_rq; 30 31 /* 32 * flush_rq shares tag with this rq, both can't be active 33 * at the same time 34 */ 35 struct request *orig_rq; 36 spinlock_t mq_flush_lock; 37 }; 38 39 extern struct kmem_cache *blk_requestq_cachep; 40 extern struct kmem_cache *request_cachep; 41 extern struct kobj_type blk_queue_ktype; 42 extern struct ida blk_queue_ida; 43 44 static inline struct blk_flush_queue *blk_get_flush_queue( 45 struct request_queue *q, struct blk_mq_ctx *ctx) 46 { 47 if (q->mq_ops) 48 return blk_mq_map_queue(q, ctx->cpu)->fq; 49 return q->fq; 50 } 51 52 static inline void __blk_get_queue(struct request_queue *q) 53 { 54 kobject_get(&q->kobj); 55 } 56 57 struct blk_flush_queue *blk_alloc_flush_queue(struct request_queue *q, 58 int node, int cmd_size); 59 void blk_free_flush_queue(struct blk_flush_queue *q); 60 61 int blk_init_rl(struct request_list *rl, struct request_queue *q, 62 gfp_t gfp_mask); 63 void blk_exit_rl(struct request_queue *q, struct request_list *rl); 64 void blk_rq_bio_prep(struct request_queue *q, struct request *rq, 65 struct bio *bio); 66 void blk_queue_bypass_start(struct request_queue *q); 67 void blk_queue_bypass_end(struct request_queue *q); 68 void __blk_queue_free_tags(struct request_queue *q); 69 void blk_freeze_queue(struct request_queue *q); 70 71 static inline void blk_queue_enter_live(struct request_queue *q) 72 { 73 /* 74 * Given that running in generic_make_request() context 75 * guarantees that a live reference against q_usage_counter has 76 * been established, further references under that same context 77 * need not check that the queue has been frozen (marked dead). 78 */ 79 percpu_ref_get(&q->q_usage_counter); 80 } 81 82 #ifdef CONFIG_BLK_DEV_INTEGRITY 83 void blk_flush_integrity(void); 84 bool __bio_integrity_endio(struct bio *); 85 static inline bool bio_integrity_endio(struct bio *bio) 86 { 87 if (bio_integrity(bio)) 88 return __bio_integrity_endio(bio); 89 return true; 90 } 91 #else 92 static inline void blk_flush_integrity(void) 93 { 94 } 95 static inline bool bio_integrity_endio(struct bio *bio) 96 { 97 return true; 98 } 99 #endif 100 101 void blk_timeout_work(struct work_struct *work); 102 unsigned long blk_rq_timeout(unsigned long timeout); 103 void blk_add_timer(struct request *req); 104 void blk_delete_timer(struct request *); 105 106 107 bool bio_attempt_front_merge(struct request_queue *q, struct request *req, 108 struct bio *bio); 109 bool bio_attempt_back_merge(struct request_queue *q, struct request *req, 110 struct bio *bio); 111 bool bio_attempt_discard_merge(struct request_queue *q, struct request *req, 112 struct bio *bio); 113 bool blk_attempt_plug_merge(struct request_queue *q, struct bio *bio, 114 unsigned int *request_count, 115 struct request **same_queue_rq); 116 unsigned int blk_plug_queued_count(struct request_queue *q); 117 118 void blk_account_io_start(struct request *req, bool new_io); 119 void blk_account_io_completion(struct request *req, unsigned int bytes); 120 void blk_account_io_done(struct request *req); 121 122 /* 123 * Internal atomic flags for request handling 124 */ 125 enum rq_atomic_flags { 126 /* 127 * Keep these two bits first - not because we depend on the 128 * value of them, but we do depend on them being in the same 129 * byte of storage to ensure ordering on writes. Keeping them 130 * first will achieve that nicely. 131 */ 132 REQ_ATOM_COMPLETE = 0, 133 REQ_ATOM_STARTED, 134 135 REQ_ATOM_POLL_SLEPT, 136 }; 137 138 /* 139 * EH timer and IO completion will both attempt to 'grab' the request, make 140 * sure that only one of them succeeds 141 */ 142 static inline int blk_mark_rq_complete(struct request *rq) 143 { 144 return test_and_set_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); 145 } 146 147 static inline void blk_clear_rq_complete(struct request *rq) 148 { 149 clear_bit(REQ_ATOM_COMPLETE, &rq->atomic_flags); 150 } 151 152 /* 153 * Internal elevator interface 154 */ 155 #define ELV_ON_HASH(rq) ((rq)->rq_flags & RQF_HASHED) 156 157 void blk_insert_flush(struct request *rq); 158 159 static inline void elv_activate_rq(struct request_queue *q, struct request *rq) 160 { 161 struct elevator_queue *e = q->elevator; 162 163 if (e->type->ops.sq.elevator_activate_req_fn) 164 e->type->ops.sq.elevator_activate_req_fn(q, rq); 165 } 166 167 static inline void elv_deactivate_rq(struct request_queue *q, struct request *rq) 168 { 169 struct elevator_queue *e = q->elevator; 170 171 if (e->type->ops.sq.elevator_deactivate_req_fn) 172 e->type->ops.sq.elevator_deactivate_req_fn(q, rq); 173 } 174 175 struct hd_struct *__disk_get_part(struct gendisk *disk, int partno); 176 177 #ifdef CONFIG_FAIL_IO_TIMEOUT 178 int blk_should_fake_timeout(struct request_queue *); 179 ssize_t part_timeout_show(struct device *, struct device_attribute *, char *); 180 ssize_t part_timeout_store(struct device *, struct device_attribute *, 181 const char *, size_t); 182 #else 183 static inline int blk_should_fake_timeout(struct request_queue *q) 184 { 185 return 0; 186 } 187 #endif 188 189 int ll_back_merge_fn(struct request_queue *q, struct request *req, 190 struct bio *bio); 191 int ll_front_merge_fn(struct request_queue *q, struct request *req, 192 struct bio *bio); 193 struct request *attempt_back_merge(struct request_queue *q, struct request *rq); 194 struct request *attempt_front_merge(struct request_queue *q, struct request *rq); 195 int blk_attempt_req_merge(struct request_queue *q, struct request *rq, 196 struct request *next); 197 void blk_recalc_rq_segments(struct request *rq); 198 void blk_rq_set_mixed_merge(struct request *rq); 199 bool blk_rq_merge_ok(struct request *rq, struct bio *bio); 200 enum elv_merge blk_try_merge(struct request *rq, struct bio *bio); 201 202 void blk_queue_congestion_threshold(struct request_queue *q); 203 204 int blk_dev_init(void); 205 206 207 /* 208 * Return the threshold (number of used requests) at which the queue is 209 * considered to be congested. It include a little hysteresis to keep the 210 * context switch rate down. 211 */ 212 static inline int queue_congestion_on_threshold(struct request_queue *q) 213 { 214 return q->nr_congestion_on; 215 } 216 217 /* 218 * The threshold at which a queue is considered to be uncongested 219 */ 220 static inline int queue_congestion_off_threshold(struct request_queue *q) 221 { 222 return q->nr_congestion_off; 223 } 224 225 extern int blk_update_nr_requests(struct request_queue *, unsigned int); 226 227 /* 228 * Contribute to IO statistics IFF: 229 * 230 * a) it's attached to a gendisk, and 231 * b) the queue had IO stats enabled when this request was started, and 232 * c) it's a file system request 233 */ 234 static inline int blk_do_io_stat(struct request *rq) 235 { 236 return rq->rq_disk && 237 (rq->rq_flags & RQF_IO_STAT) && 238 !blk_rq_is_passthrough(rq); 239 } 240 241 static inline void req_set_nomerge(struct request_queue *q, struct request *req) 242 { 243 req->cmd_flags |= REQ_NOMERGE; 244 if (req == q->last_merge) 245 q->last_merge = NULL; 246 } 247 248 /* 249 * Internal io_context interface 250 */ 251 void get_io_context(struct io_context *ioc); 252 struct io_cq *ioc_lookup_icq(struct io_context *ioc, struct request_queue *q); 253 struct io_cq *ioc_create_icq(struct io_context *ioc, struct request_queue *q, 254 gfp_t gfp_mask); 255 void ioc_clear_queue(struct request_queue *q); 256 257 int create_task_io_context(struct task_struct *task, gfp_t gfp_mask, int node); 258 259 /** 260 * rq_ioc - determine io_context for request allocation 261 * @bio: request being allocated is for this bio (can be %NULL) 262 * 263 * Determine io_context to use for request allocation for @bio. May return 264 * %NULL if %current->io_context doesn't exist. 265 */ 266 static inline struct io_context *rq_ioc(struct bio *bio) 267 { 268 #ifdef CONFIG_BLK_CGROUP 269 if (bio && bio->bi_ioc) 270 return bio->bi_ioc; 271 #endif 272 return current->io_context; 273 } 274 275 /** 276 * create_io_context - try to create task->io_context 277 * @gfp_mask: allocation mask 278 * @node: allocation node 279 * 280 * If %current->io_context is %NULL, allocate a new io_context and install 281 * it. Returns the current %current->io_context which may be %NULL if 282 * allocation failed. 283 * 284 * Note that this function can't be called with IRQ disabled because 285 * task_lock which protects %current->io_context is IRQ-unsafe. 286 */ 287 static inline struct io_context *create_io_context(gfp_t gfp_mask, int node) 288 { 289 WARN_ON_ONCE(irqs_disabled()); 290 if (unlikely(!current->io_context)) 291 create_task_io_context(current, gfp_mask, node); 292 return current->io_context; 293 } 294 295 /* 296 * Internal throttling interface 297 */ 298 #ifdef CONFIG_BLK_DEV_THROTTLING 299 extern void blk_throtl_drain(struct request_queue *q); 300 extern int blk_throtl_init(struct request_queue *q); 301 extern void blk_throtl_exit(struct request_queue *q); 302 extern void blk_throtl_register_queue(struct request_queue *q); 303 #else /* CONFIG_BLK_DEV_THROTTLING */ 304 static inline void blk_throtl_drain(struct request_queue *q) { } 305 static inline int blk_throtl_init(struct request_queue *q) { return 0; } 306 static inline void blk_throtl_exit(struct request_queue *q) { } 307 static inline void blk_throtl_register_queue(struct request_queue *q) { } 308 #endif /* CONFIG_BLK_DEV_THROTTLING */ 309 #ifdef CONFIG_BLK_DEV_THROTTLING_LOW 310 extern ssize_t blk_throtl_sample_time_show(struct request_queue *q, char *page); 311 extern ssize_t blk_throtl_sample_time_store(struct request_queue *q, 312 const char *page, size_t count); 313 extern void blk_throtl_bio_endio(struct bio *bio); 314 extern void blk_throtl_stat_add(struct request *rq, u64 time); 315 #else 316 static inline void blk_throtl_bio_endio(struct bio *bio) { } 317 static inline void blk_throtl_stat_add(struct request *rq, u64 time) { } 318 #endif 319 320 #ifdef CONFIG_BOUNCE 321 extern int init_emergency_isa_pool(void); 322 extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); 323 #else 324 static inline int init_emergency_isa_pool(void) 325 { 326 return 0; 327 } 328 static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) 329 { 330 } 331 #endif /* CONFIG_BOUNCE */ 332 333 #endif /* BLK_INTERNAL_H */ 334