1 #ifndef BLK_MQ_H 2 #define BLK_MQ_H 3 4 #include <linux/blkdev.h> 5 #include <linux/sbitmap.h> 6 #include <linux/srcu.h> 7 8 struct blk_mq_tags; 9 struct blk_flush_queue; 10 11 struct blk_mq_hw_ctx { 12 struct { 13 spinlock_t lock; 14 struct list_head dispatch; 15 unsigned long state; /* BLK_MQ_S_* flags */ 16 } ____cacheline_aligned_in_smp; 17 18 struct work_struct run_work; 19 cpumask_var_t cpumask; 20 int next_cpu; 21 int next_cpu_batch; 22 23 unsigned long flags; /* BLK_MQ_F_* flags */ 24 25 void *sched_data; 26 struct request_queue *queue; 27 struct blk_flush_queue *fq; 28 29 void *driver_data; 30 31 struct sbitmap ctx_map; 32 33 struct blk_mq_ctx **ctxs; 34 unsigned int nr_ctx; 35 36 wait_queue_t dispatch_wait; 37 atomic_t wait_index; 38 39 struct blk_mq_tags *tags; 40 struct blk_mq_tags *sched_tags; 41 42 struct srcu_struct queue_rq_srcu; 43 44 unsigned long queued; 45 unsigned long run; 46 #define BLK_MQ_MAX_DISPATCH_ORDER 7 47 unsigned long dispatched[BLK_MQ_MAX_DISPATCH_ORDER]; 48 49 unsigned int numa_node; 50 unsigned int queue_num; 51 52 atomic_t nr_active; 53 54 struct delayed_work delay_work; 55 56 struct hlist_node cpuhp_dead; 57 struct kobject kobj; 58 59 unsigned long poll_considered; 60 unsigned long poll_invoked; 61 unsigned long poll_success; 62 }; 63 64 struct blk_mq_tag_set { 65 unsigned int *mq_map; 66 const struct blk_mq_ops *ops; 67 unsigned int nr_hw_queues; 68 unsigned int queue_depth; /* max hw supported */ 69 unsigned int reserved_tags; 70 unsigned int cmd_size; /* per-request extra data */ 71 int numa_node; 72 unsigned int timeout; 73 unsigned int flags; /* BLK_MQ_F_* */ 74 void *driver_data; 75 76 struct blk_mq_tags **tags; 77 78 struct mutex tag_list_lock; 79 struct list_head tag_list; 80 }; 81 82 struct blk_mq_queue_data { 83 struct request *rq; 84 struct list_head *list; 85 bool last; 86 }; 87 88 typedef int (queue_rq_fn)(struct blk_mq_hw_ctx *, const struct blk_mq_queue_data *); 89 typedef enum blk_eh_timer_return (timeout_fn)(struct request *, bool); 90 typedef int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int); 91 typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int); 92 typedef int (init_request_fn)(void *, struct request *, unsigned int, 93 unsigned int, unsigned int); 94 typedef void (exit_request_fn)(void *, struct request *, unsigned int, 95 unsigned int); 96 typedef int (reinit_request_fn)(void *, struct request *); 97 98 typedef void (busy_iter_fn)(struct blk_mq_hw_ctx *, struct request *, void *, 99 bool); 100 typedef void (busy_tag_iter_fn)(struct request *, void *, bool); 101 typedef int (poll_fn)(struct blk_mq_hw_ctx *, unsigned int); 102 typedef int (map_queues_fn)(struct blk_mq_tag_set *set); 103 104 105 struct blk_mq_ops { 106 /* 107 * Queue request 108 */ 109 queue_rq_fn *queue_rq; 110 111 /* 112 * Called on request timeout 113 */ 114 timeout_fn *timeout; 115 116 /* 117 * Called to poll for completion of a specific tag. 118 */ 119 poll_fn *poll; 120 121 softirq_done_fn *complete; 122 123 /* 124 * Called when the block layer side of a hardware queue has been 125 * set up, allowing the driver to allocate/init matching structures. 126 * Ditto for exit/teardown. 127 */ 128 init_hctx_fn *init_hctx; 129 exit_hctx_fn *exit_hctx; 130 131 /* 132 * Called for every command allocated by the block layer to allow 133 * the driver to set up driver specific data. 134 * 135 * Tag greater than or equal to queue_depth is for setting up 136 * flush request. 137 * 138 * Ditto for exit/teardown. 139 */ 140 init_request_fn *init_request; 141 exit_request_fn *exit_request; 142 reinit_request_fn *reinit_request; 143 144 map_queues_fn *map_queues; 145 }; 146 147 enum { 148 BLK_MQ_RQ_QUEUE_OK = 0, /* queued fine */ 149 BLK_MQ_RQ_QUEUE_BUSY = 1, /* requeue IO for later */ 150 BLK_MQ_RQ_QUEUE_ERROR = 2, /* end IO with error */ 151 152 BLK_MQ_F_SHOULD_MERGE = 1 << 0, 153 BLK_MQ_F_TAG_SHARED = 1 << 1, 154 BLK_MQ_F_SG_MERGE = 1 << 2, 155 BLK_MQ_F_DEFER_ISSUE = 1 << 4, 156 BLK_MQ_F_BLOCKING = 1 << 5, 157 BLK_MQ_F_NO_SCHED = 1 << 6, 158 BLK_MQ_F_ALLOC_POLICY_START_BIT = 8, 159 BLK_MQ_F_ALLOC_POLICY_BITS = 1, 160 161 BLK_MQ_S_STOPPED = 0, 162 BLK_MQ_S_TAG_ACTIVE = 1, 163 BLK_MQ_S_SCHED_RESTART = 2, 164 BLK_MQ_S_TAG_WAITING = 3, 165 166 BLK_MQ_MAX_DEPTH = 10240, 167 168 BLK_MQ_CPU_WORK_BATCH = 8, 169 }; 170 #define BLK_MQ_FLAG_TO_ALLOC_POLICY(flags) \ 171 ((flags >> BLK_MQ_F_ALLOC_POLICY_START_BIT) & \ 172 ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) 173 #define BLK_ALLOC_POLICY_TO_MQ_FLAG(policy) \ 174 ((policy & ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) \ 175 << BLK_MQ_F_ALLOC_POLICY_START_BIT) 176 177 struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *); 178 struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, 179 struct request_queue *q); 180 int blk_mq_register_dev(struct device *, struct request_queue *); 181 void blk_mq_unregister_dev(struct device *, struct request_queue *); 182 183 int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set); 184 void blk_mq_free_tag_set(struct blk_mq_tag_set *set); 185 186 void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule); 187 188 void blk_mq_free_request(struct request *rq); 189 bool blk_mq_can_queue(struct blk_mq_hw_ctx *); 190 191 enum { 192 BLK_MQ_REQ_NOWAIT = (1 << 0), /* return when out of requests */ 193 BLK_MQ_REQ_RESERVED = (1 << 1), /* allocate from reserved pool */ 194 BLK_MQ_REQ_INTERNAL = (1 << 2), /* allocate internal/sched tag */ 195 }; 196 197 struct request *blk_mq_alloc_request(struct request_queue *q, int rw, 198 unsigned int flags); 199 struct request *blk_mq_alloc_request_hctx(struct request_queue *q, int op, 200 unsigned int flags, unsigned int hctx_idx); 201 struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag); 202 203 enum { 204 BLK_MQ_UNIQUE_TAG_BITS = 16, 205 BLK_MQ_UNIQUE_TAG_MASK = (1 << BLK_MQ_UNIQUE_TAG_BITS) - 1, 206 }; 207 208 u32 blk_mq_unique_tag(struct request *rq); 209 210 static inline u16 blk_mq_unique_tag_to_hwq(u32 unique_tag) 211 { 212 return unique_tag >> BLK_MQ_UNIQUE_TAG_BITS; 213 } 214 215 static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag) 216 { 217 return unique_tag & BLK_MQ_UNIQUE_TAG_MASK; 218 } 219 220 221 int blk_mq_request_started(struct request *rq); 222 void blk_mq_start_request(struct request *rq); 223 void blk_mq_end_request(struct request *rq, int error); 224 void __blk_mq_end_request(struct request *rq, int error); 225 226 void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list); 227 void blk_mq_add_to_requeue_list(struct request *rq, bool at_head, 228 bool kick_requeue_list); 229 void blk_mq_kick_requeue_list(struct request_queue *q); 230 void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs); 231 void blk_mq_abort_requeue_list(struct request_queue *q); 232 void blk_mq_complete_request(struct request *rq, int error); 233 234 bool blk_mq_queue_stopped(struct request_queue *q); 235 void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx); 236 void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx); 237 void blk_mq_stop_hw_queues(struct request_queue *q); 238 void blk_mq_start_hw_queues(struct request_queue *q); 239 void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async); 240 void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async); 241 void blk_mq_run_hw_queues(struct request_queue *q, bool async); 242 void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs); 243 void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, 244 busy_tag_iter_fn *fn, void *priv); 245 void blk_mq_freeze_queue(struct request_queue *q); 246 void blk_mq_unfreeze_queue(struct request_queue *q); 247 void blk_mq_freeze_queue_start(struct request_queue *q); 248 void blk_mq_freeze_queue_wait(struct request_queue *q); 249 int blk_mq_freeze_queue_wait_timeout(struct request_queue *q, 250 unsigned long timeout); 251 int blk_mq_reinit_tagset(struct blk_mq_tag_set *set); 252 253 int blk_mq_map_queues(struct blk_mq_tag_set *set); 254 void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues); 255 256 /* 257 * Driver command data is immediately after the request. So subtract request 258 * size to get back to the original request, add request size to get the PDU. 259 */ 260 static inline struct request *blk_mq_rq_from_pdu(void *pdu) 261 { 262 return pdu - sizeof(struct request); 263 } 264 static inline void *blk_mq_rq_to_pdu(struct request *rq) 265 { 266 return rq + 1; 267 } 268 269 #define queue_for_each_hw_ctx(q, hctx, i) \ 270 for ((i) = 0; (i) < (q)->nr_hw_queues && \ 271 ({ hctx = (q)->queue_hw_ctx[i]; 1; }); (i)++) 272 273 #define hctx_for_each_ctx(hctx, ctx, i) \ 274 for ((i) = 0; (i) < (hctx)->nr_ctx && \ 275 ({ ctx = (hctx)->ctxs[(i)]; 1; }); (i)++) 276 277 #endif 278