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 struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx, 48 struct blk_mq_ctx *start); 49 50 /* 51 * Internal helpers for allocating/freeing the request map 52 */ 53 void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, 54 unsigned int hctx_idx); 55 void blk_mq_free_rq_map(struct blk_mq_tags *tags); 56 struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set, 57 unsigned int hctx_idx, 58 unsigned int nr_tags, 59 unsigned int reserved_tags); 60 int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags, 61 unsigned int hctx_idx, unsigned int depth); 62 63 /* 64 * Internal helpers for request insertion into sw queues 65 */ 66 void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq, 67 bool at_head); 68 void blk_mq_request_bypass_insert(struct request *rq, bool at_head, 69 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 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 unsigned int cmd_flags; 154 155 /* input & output parameter */ 156 struct blk_mq_ctx *ctx; 157 struct blk_mq_hw_ctx *hctx; 158 }; 159 160 static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data) 161 { 162 if (data->flags & BLK_MQ_REQ_INTERNAL) 163 return data->hctx->sched_tags; 164 165 return data->hctx->tags; 166 } 167 168 static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx) 169 { 170 return test_bit(BLK_MQ_S_STOPPED, &hctx->state); 171 } 172 173 static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx) 174 { 175 return hctx->nr_ctx && hctx->tags; 176 } 177 178 unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part); 179 void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part, 180 unsigned int inflight[2]); 181 182 static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx) 183 { 184 struct request_queue *q = hctx->queue; 185 186 if (q->mq_ops->put_budget) 187 q->mq_ops->put_budget(hctx); 188 } 189 190 static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx) 191 { 192 struct request_queue *q = hctx->queue; 193 194 if (q->mq_ops->get_budget) 195 return q->mq_ops->get_budget(hctx); 196 return true; 197 } 198 199 static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx, 200 struct request *rq) 201 { 202 blk_mq_put_tag(hctx->tags, rq->mq_ctx, rq->tag); 203 rq->tag = BLK_MQ_NO_TAG; 204 205 if (rq->rq_flags & RQF_MQ_INFLIGHT) { 206 rq->rq_flags &= ~RQF_MQ_INFLIGHT; 207 atomic_dec(&hctx->nr_active); 208 } 209 } 210 211 static inline void blk_mq_put_driver_tag(struct request *rq) 212 { 213 if (rq->tag == BLK_MQ_NO_TAG || rq->internal_tag == BLK_MQ_NO_TAG) 214 return; 215 216 __blk_mq_put_driver_tag(rq->mq_hctx, rq); 217 } 218 219 static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap) 220 { 221 int cpu; 222 223 for_each_possible_cpu(cpu) 224 qmap->mq_map[cpu] = 0; 225 } 226 227 /* 228 * blk_mq_plug() - Get caller context plug 229 * @q: request queue 230 * @bio : the bio being submitted by the caller context 231 * 232 * Plugging, by design, may delay the insertion of BIOs into the elevator in 233 * order to increase BIO merging opportunities. This however can cause BIO 234 * insertion order to change from the order in which submit_bio() is being 235 * executed in the case of multiple contexts concurrently issuing BIOs to a 236 * device, even if these context are synchronized to tightly control BIO issuing 237 * order. While this is not a problem with regular block devices, this ordering 238 * change can cause write BIO failures with zoned block devices as these 239 * require sequential write patterns to zones. Prevent this from happening by 240 * ignoring the plug state of a BIO issuing context if the target request queue 241 * is for a zoned block device and the BIO to plug is a write operation. 242 * 243 * Return current->plug if the bio can be plugged and NULL otherwise 244 */ 245 static inline struct blk_plug *blk_mq_plug(struct request_queue *q, 246 struct bio *bio) 247 { 248 /* 249 * For regular block devices or read operations, use the context plug 250 * which may be NULL if blk_start_plug() was not executed. 251 */ 252 if (!blk_queue_is_zoned(q) || !op_is_write(bio_op(bio))) 253 return current->plug; 254 255 /* Zoned block device write operation case: do not plug the BIO */ 256 return NULL; 257 } 258 259 #endif 260