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 delayed_work 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 hlist_node cpuhp_dead; 55 struct kobject kobj; 56 57 unsigned long poll_considered; 58 unsigned long poll_invoked; 59 unsigned long poll_success; 60 61 #ifdef CONFIG_BLK_DEBUG_FS 62 struct dentry *debugfs_dir; 63 struct dentry *sched_debugfs_dir; 64 #endif 65 }; 66 67 struct blk_mq_tag_set { 68 unsigned int *mq_map; 69 const struct blk_mq_ops *ops; 70 unsigned int nr_hw_queues; 71 unsigned int queue_depth; /* max hw supported */ 72 unsigned int reserved_tags; 73 unsigned int cmd_size; /* per-request extra data */ 74 int numa_node; 75 unsigned int timeout; 76 unsigned int flags; /* BLK_MQ_F_* */ 77 void *driver_data; 78 79 struct blk_mq_tags **tags; 80 81 struct mutex tag_list_lock; 82 struct list_head tag_list; 83 }; 84 85 struct blk_mq_queue_data { 86 struct request *rq; 87 bool last; 88 }; 89 90 typedef int (queue_rq_fn)(struct blk_mq_hw_ctx *, const struct blk_mq_queue_data *); 91 typedef enum blk_eh_timer_return (timeout_fn)(struct request *, bool); 92 typedef int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int); 93 typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int); 94 typedef int (init_request_fn)(struct blk_mq_tag_set *set, struct request *, 95 unsigned int, unsigned int); 96 typedef void (exit_request_fn)(struct blk_mq_tag_set *set, struct request *, 97 unsigned int); 98 typedef int (reinit_request_fn)(void *, struct request *); 99 100 typedef void (busy_iter_fn)(struct blk_mq_hw_ctx *, struct request *, void *, 101 bool); 102 typedef void (busy_tag_iter_fn)(struct request *, void *, bool); 103 typedef int (poll_fn)(struct blk_mq_hw_ctx *, unsigned int); 104 typedef int (map_queues_fn)(struct blk_mq_tag_set *set); 105 106 107 struct blk_mq_ops { 108 /* 109 * Queue request 110 */ 111 queue_rq_fn *queue_rq; 112 113 /* 114 * Called on request timeout 115 */ 116 timeout_fn *timeout; 117 118 /* 119 * Called to poll for completion of a specific tag. 120 */ 121 poll_fn *poll; 122 123 softirq_done_fn *complete; 124 125 /* 126 * Called when the block layer side of a hardware queue has been 127 * set up, allowing the driver to allocate/init matching structures. 128 * Ditto for exit/teardown. 129 */ 130 init_hctx_fn *init_hctx; 131 exit_hctx_fn *exit_hctx; 132 133 /* 134 * Called for every command allocated by the block layer to allow 135 * the driver to set up driver specific data. 136 * 137 * Tag greater than or equal to queue_depth is for setting up 138 * flush request. 139 * 140 * Ditto for exit/teardown. 141 */ 142 init_request_fn *init_request; 143 exit_request_fn *exit_request; 144 reinit_request_fn *reinit_request; 145 146 map_queues_fn *map_queues; 147 148 #ifdef CONFIG_BLK_DEBUG_FS 149 /* 150 * Used by the debugfs implementation to show driver-specific 151 * information about a request. 152 */ 153 void (*show_rq)(struct seq_file *m, struct request *rq); 154 #endif 155 }; 156 157 enum { 158 BLK_MQ_RQ_QUEUE_OK = 0, /* queued fine */ 159 BLK_MQ_RQ_QUEUE_BUSY = 1, /* requeue IO for later */ 160 BLK_MQ_RQ_QUEUE_ERROR = 2, /* end IO with error */ 161 162 BLK_MQ_F_SHOULD_MERGE = 1 << 0, 163 BLK_MQ_F_TAG_SHARED = 1 << 1, 164 BLK_MQ_F_SG_MERGE = 1 << 2, 165 BLK_MQ_F_BLOCKING = 1 << 5, 166 BLK_MQ_F_NO_SCHED = 1 << 6, 167 BLK_MQ_F_ALLOC_POLICY_START_BIT = 8, 168 BLK_MQ_F_ALLOC_POLICY_BITS = 1, 169 170 BLK_MQ_S_STOPPED = 0, 171 BLK_MQ_S_TAG_ACTIVE = 1, 172 BLK_MQ_S_SCHED_RESTART = 2, 173 BLK_MQ_S_TAG_WAITING = 3, 174 BLK_MQ_S_START_ON_RUN = 4, 175 176 BLK_MQ_MAX_DEPTH = 10240, 177 178 BLK_MQ_CPU_WORK_BATCH = 8, 179 }; 180 #define BLK_MQ_FLAG_TO_ALLOC_POLICY(flags) \ 181 ((flags >> BLK_MQ_F_ALLOC_POLICY_START_BIT) & \ 182 ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) 183 #define BLK_ALLOC_POLICY_TO_MQ_FLAG(policy) \ 184 ((policy & ((1 << BLK_MQ_F_ALLOC_POLICY_BITS) - 1)) \ 185 << BLK_MQ_F_ALLOC_POLICY_START_BIT) 186 187 struct request_queue *blk_mq_init_queue(struct blk_mq_tag_set *); 188 struct request_queue *blk_mq_init_allocated_queue(struct blk_mq_tag_set *set, 189 struct request_queue *q); 190 int blk_mq_register_dev(struct device *, struct request_queue *); 191 void blk_mq_unregister_dev(struct device *, struct request_queue *); 192 193 int blk_mq_alloc_tag_set(struct blk_mq_tag_set *set); 194 void blk_mq_free_tag_set(struct blk_mq_tag_set *set); 195 196 void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule); 197 198 void blk_mq_free_request(struct request *rq); 199 bool blk_mq_can_queue(struct blk_mq_hw_ctx *); 200 201 enum { 202 BLK_MQ_REQ_NOWAIT = (1 << 0), /* return when out of requests */ 203 BLK_MQ_REQ_RESERVED = (1 << 1), /* allocate from reserved pool */ 204 BLK_MQ_REQ_INTERNAL = (1 << 2), /* allocate internal/sched tag */ 205 }; 206 207 struct request *blk_mq_alloc_request(struct request_queue *q, int rw, 208 unsigned int flags); 209 struct request *blk_mq_alloc_request_hctx(struct request_queue *q, int op, 210 unsigned int flags, unsigned int hctx_idx); 211 struct request *blk_mq_tag_to_rq(struct blk_mq_tags *tags, unsigned int tag); 212 213 enum { 214 BLK_MQ_UNIQUE_TAG_BITS = 16, 215 BLK_MQ_UNIQUE_TAG_MASK = (1 << BLK_MQ_UNIQUE_TAG_BITS) - 1, 216 }; 217 218 u32 blk_mq_unique_tag(struct request *rq); 219 220 static inline u16 blk_mq_unique_tag_to_hwq(u32 unique_tag) 221 { 222 return unique_tag >> BLK_MQ_UNIQUE_TAG_BITS; 223 } 224 225 static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag) 226 { 227 return unique_tag & BLK_MQ_UNIQUE_TAG_MASK; 228 } 229 230 231 int blk_mq_request_started(struct request *rq); 232 void blk_mq_start_request(struct request *rq); 233 void blk_mq_end_request(struct request *rq, int error); 234 void __blk_mq_end_request(struct request *rq, int error); 235 236 void blk_mq_requeue_request(struct request *rq, bool kick_requeue_list); 237 void blk_mq_add_to_requeue_list(struct request *rq, bool at_head, 238 bool kick_requeue_list); 239 void blk_mq_kick_requeue_list(struct request_queue *q); 240 void blk_mq_delay_kick_requeue_list(struct request_queue *q, unsigned long msecs); 241 void blk_mq_complete_request(struct request *rq); 242 243 bool blk_mq_queue_stopped(struct request_queue *q); 244 void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx); 245 void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx); 246 void blk_mq_stop_hw_queues(struct request_queue *q); 247 void blk_mq_start_hw_queues(struct request_queue *q); 248 void blk_mq_start_stopped_hw_queue(struct blk_mq_hw_ctx *hctx, bool async); 249 void blk_mq_start_stopped_hw_queues(struct request_queue *q, bool async); 250 void blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs); 251 void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async); 252 void blk_mq_run_hw_queues(struct request_queue *q, bool async); 253 void blk_mq_delay_queue(struct blk_mq_hw_ctx *hctx, unsigned long msecs); 254 void blk_mq_tagset_busy_iter(struct blk_mq_tag_set *tagset, 255 busy_tag_iter_fn *fn, void *priv); 256 void blk_mq_freeze_queue(struct request_queue *q); 257 void blk_mq_unfreeze_queue(struct request_queue *q); 258 void blk_freeze_queue_start(struct request_queue *q); 259 void blk_mq_freeze_queue_wait(struct request_queue *q); 260 int blk_mq_freeze_queue_wait_timeout(struct request_queue *q, 261 unsigned long timeout); 262 int blk_mq_reinit_tagset(struct blk_mq_tag_set *set); 263 264 int blk_mq_map_queues(struct blk_mq_tag_set *set); 265 void blk_mq_update_nr_hw_queues(struct blk_mq_tag_set *set, int nr_hw_queues); 266 267 /* 268 * Driver command data is immediately after the request. So subtract request 269 * size to get back to the original request, add request size to get the PDU. 270 */ 271 static inline struct request *blk_mq_rq_from_pdu(void *pdu) 272 { 273 return pdu - sizeof(struct request); 274 } 275 static inline void *blk_mq_rq_to_pdu(struct request *rq) 276 { 277 return rq + 1; 278 } 279 280 #define queue_for_each_hw_ctx(q, hctx, i) \ 281 for ((i) = 0; (i) < (q)->nr_hw_queues && \ 282 ({ hctx = (q)->queue_hw_ctx[i]; 1; }); (i)++) 283 284 #define hctx_for_each_ctx(hctx, ctx, i) \ 285 for ((i) = 0; (i) < (hctx)->nr_ctx && \ 286 ({ ctx = (hctx)->ctxs[(i)]; 1; }); (i)++) 287 288 #endif 289