1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef INT_BLK_MQ_H 3 #define INT_BLK_MQ_H 4 5 #include "blk-stat.h" 6 #include "blk-mq-tag.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 /* incremented at dispatch time */ 29 unsigned long rq_dispatched[2]; 30 unsigned long rq_merged; 31 32 /* incremented at completion time */ 33 unsigned long ____cacheline_aligned_in_smp rq_completed[2]; 34 35 struct request_queue *queue; 36 struct blk_mq_ctxs *ctxs; 37 struct kobject kobj; 38 } ____cacheline_aligned_in_smp; 39 40 void blk_mq_exit_queue(struct request_queue *q); 41 int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr); 42 void blk_mq_wake_waiters(struct request_queue *q); 43 bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool); 44 void blk_mq_add_to_requeue_list(struct request *rq, bool at_head, 45 bool kick_requeue_list); 46 void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list); 47 bool blk_mq_get_driver_tag(struct request *rq); 48 struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx, 49 struct blk_mq_ctx *start); 50 51 /* 52 * Internal helpers for allocating/freeing the request map 53 */ 54 void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, 55 unsigned int hctx_idx); 56 void blk_mq_free_rq_map(struct blk_mq_tags *tags); 57 struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set, 58 unsigned int hctx_idx, 59 unsigned int nr_tags, 60 unsigned int reserved_tags); 61 int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, 62 unsigned int hctx_idx, unsigned int depth); 63 64 /* 65 * Internal helpers for request insertion into sw queues 66 */ 67 void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, 68 bool at_head); 69 void blk_mq_request_bypass_insert(struct request *rq, bool run_queue); 70 void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx, 71 struct list_head *list); 72 73 /* Used by blk_insert_cloned_request() to issue request directly */ 74 blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last); 75 void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx, 76 struct list_head *list); 77 78 /* 79 * CPU -> queue mappings 80 */ 81 extern int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int); 82 83 /* 84 * blk_mq_map_queue_type() - map (hctx_type,cpu) to hardware queue 85 * @q: request queue 86 * @type: the hctx type index 87 * @cpu: CPU 88 */ 89 static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q, 90 enum hctx_type type, 91 unsigned int cpu) 92 { 93 return q->queue_hw_ctx[q->tag_set->map[type].mq_map[cpu]]; 94 } 95 96 /* 97 * blk_mq_map_queue() - map (cmd_flags,type) to hardware queue 98 * @q: request queue 99 * @flags: request command flags 100 * @cpu: cpu ctx 101 */ 102 static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q, 103 unsigned int flags, 104 struct blk_mq_ctx *ctx) 105 { 106 enum hctx_type type = HCTX_TYPE_DEFAULT; 107 108 /* 109 * The caller ensure that if REQ_HIPRI, poll must be enabled. 110 */ 111 if (flags & REQ_HIPRI) 112 type = HCTX_TYPE_POLL; 113 else if ((flags & REQ_OP_MASK) == REQ_OP_READ) 114 type = HCTX_TYPE_READ; 115 116 return ctx->hctxs[type]; 117 } 118 119 /* 120 * sysfs helpers 121 */ 122 extern void blk_mq_sysfs_init(struct request_queue *q); 123 extern void blk_mq_sysfs_deinit(struct request_queue *q); 124 extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q); 125 extern int blk_mq_sysfs_register(struct request_queue *q); 126 extern void blk_mq_sysfs_unregister(struct request_queue *q); 127 extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx); 128 129 void blk_mq_release(struct request_queue *q); 130 131 /** 132 * blk_mq_rq_state() - read the current MQ_RQ_* state of a request 133 * @rq: target request. 134 */ 135 static inline enum mq_rq_state blk_mq_rq_state(struct request *rq) 136 { 137 return READ_ONCE(rq->state); 138 } 139 140 static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q, 141 unsigned int cpu) 142 { 143 return per_cpu_ptr(q->queue_ctx, cpu); 144 } 145 146 /* 147 * This assumes per-cpu software queueing queues. They could be per-node 148 * as well, for instance. For now this is hardcoded as-is. Note that we don't 149 * care about preemption, since we know the ctx's are persistent. This does 150 * mean that we can't rely on ctx always matching the currently running CPU. 151 */ 152 static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q) 153 { 154 return __blk_mq_get_ctx(q, raw_smp_processor_id()); 155 } 156 157 struct blk_mq_alloc_data { 158 /* input parameter */ 159 struct request_queue *q; 160 blk_mq_req_flags_t flags; 161 unsigned int shallow_depth; 162 unsigned int cmd_flags; 163 164 /* input & output parameter */ 165 struct blk_mq_ctx *ctx; 166 struct blk_mq_hw_ctx *hctx; 167 }; 168 169 static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data) 170 { 171 if (data->flags & BLK_MQ_REQ_INTERNAL) 172 return data->hctx->sched_tags; 173 174 return data->hctx->tags; 175 } 176 177 static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx) 178 { 179 return test_bit(BLK_MQ_S_STOPPED, &hctx->state); 180 } 181 182 static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx) 183 { 184 return hctx->nr_ctx && hctx->tags; 185 } 186 187 unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part); 188 void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part, 189 unsigned int inflight[2]); 190 191 static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx) 192 { 193 struct request_queue *q = hctx->queue; 194 195 if (q->mq_ops->put_budget) 196 q->mq_ops->put_budget(hctx); 197 } 198 199 static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx) 200 { 201 struct request_queue *q = hctx->queue; 202 203 if (q->mq_ops->get_budget) 204 return q->mq_ops->get_budget(hctx); 205 return true; 206 } 207 208 static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, 209 struct request *rq) 210 { 211 blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag); 212 rq->tag = -1; 213 214 if (rq->rq_flags & RQF_MQ_INFLIGHT) { 215 rq->rq_flags &= ~RQF_MQ_INFLIGHT; 216 atomic_dec(&hctx->nr_active); 217 } 218 } 219 220 static inline void blk_mq_put_driver_tag(struct request *rq) 221 { 222 if (rq->tag == -1 || rq->internal_tag == -1) 223 return; 224 225 __blk_mq_put_driver_tag(rq->mq_hctx, rq); 226 } 227 228 static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap) 229 { 230 int cpu; 231 232 for_each_possible_cpu(cpu) 233 qmap->mq_map[cpu] = 0; 234 } 235 236 /* 237 * blk_mq_plug() - Get caller context plug 238 * @q: request queue 239 * @bio : the bio being submitted by the caller context 240 * 241 * Plugging, by design, may delay the insertion of BIOs into the elevator in 242 * order to increase BIO merging opportunities. This however can cause BIO 243 * insertion order to change from the order in which submit_bio() is being 244 * executed in the case of multiple contexts concurrently issuing BIOs to a 245 * device, even if these context are synchronized to tightly control BIO issuing 246 * order. While this is not a problem with regular block devices, this ordering 247 * change can cause write BIO failures with zoned block devices as these 248 * require sequential write patterns to zones. Prevent this from happening by 249 * ignoring the plug state of a BIO issuing context if the target request queue 250 * is for a zoned block device and the BIO to plug is a write operation. 251 * 252 * Return current->plug if the bio can be plugged and NULL otherwise 253 */ 254 static inline struct blk_plug *blk_mq_plug(struct request_queue *q, 255 struct bio *bio) 256 { 257 /* 258 * For regular block devices or read operations, use the context plug 259 * which may be NULL if blk_start_plug() was not executed. 260 */ 261 if (!blk_queue_is_zoned(q) || !op_is_write(bio_op(bio))) 262 return current->plug; 263 264 /* Zoned block device write operation case: do not plug the BIO */ 265 return NULL; 266 } 267 268 #endif 269