blk-mq.h revision 5d12f905cc50c0810628d0deedd478ec2db48659
1#ifndef BLK_MQ_H 2#define BLK_MQ_H 3 4#include <linux/blkdev.h> 5 6struct blk_mq_tags; 7 8struct blk_mq_cpu_notifier { 9 struct list_head list; 10 void *data; 11 void (*notify)(void *data, unsigned long action, unsigned int cpu); 12}; 13 14struct blk_mq_hw_ctx { 15 struct { 16 spinlock_t lock; 17 struct list_head dispatch; 18 } ____cacheline_aligned_in_smp; 19 20 unsigned long state; /* BLK_MQ_S_* flags */ 21 struct delayed_work delayed_work; 22 23 unsigned long flags; /* BLK_MQ_F_* flags */ 24 25 struct request_queue *queue; 26 unsigned int queue_num; 27 28 void *driver_data; 29 30 unsigned int nr_ctx; 31 struct blk_mq_ctx **ctxs; 32 unsigned int nr_ctx_map; 33 unsigned long *ctx_map; 34 35 struct request **rqs; 36 struct list_head page_list; 37 struct blk_mq_tags *tags; 38 39 unsigned long queued; 40 unsigned long run; 41#define BLK_MQ_MAX_DISPATCH_ORDER 10 42 unsigned long dispatched[BLK_MQ_MAX_DISPATCH_ORDER]; 43 44 unsigned int queue_depth; 45 unsigned int numa_node; 46 unsigned int cmd_size; /* per-request extra data */ 47 48 struct blk_mq_cpu_notifier cpu_notifier; 49 struct kobject kobj; 50}; 51 52struct blk_mq_reg { 53 struct blk_mq_ops *ops; 54 unsigned int nr_hw_queues; 55 unsigned int queue_depth; 56 unsigned int reserved_tags; 57 unsigned int cmd_size; /* per-request extra data */ 58 int numa_node; 59 unsigned int timeout; 60 unsigned int flags; /* BLK_MQ_F_* */ 61}; 62 63typedef int (queue_rq_fn)(struct blk_mq_hw_ctx *, struct request *); 64typedef struct blk_mq_hw_ctx *(map_queue_fn)(struct request_queue *, const int); 65typedef struct blk_mq_hw_ctx *(alloc_hctx_fn)(struct blk_mq_reg *,unsigned int); 66typedef void (free_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int); 67typedef int (init_hctx_fn)(struct blk_mq_hw_ctx *, void *, unsigned int); 68typedef void (exit_hctx_fn)(struct blk_mq_hw_ctx *, unsigned int); 69 70struct blk_mq_ops { 71 /* 72 * Queue request 73 */ 74 queue_rq_fn *queue_rq; 75 76 /* 77 * Map to specific hardware queue 78 */ 79 map_queue_fn *map_queue; 80 81 /* 82 * Called on request timeout 83 */ 84 rq_timed_out_fn *timeout; 85 86 softirq_done_fn *complete; 87 88 /* 89 * Override for hctx allocations (should probably go) 90 */ 91 alloc_hctx_fn *alloc_hctx; 92 free_hctx_fn *free_hctx; 93 94 /* 95 * Called when the block layer side of a hardware queue has been 96 * set up, allowing the driver to allocate/init matching structures. 97 * Ditto for exit/teardown. 98 */ 99 init_hctx_fn *init_hctx; 100 exit_hctx_fn *exit_hctx; 101}; 102 103enum { 104 BLK_MQ_RQ_QUEUE_OK = 0, /* queued fine */ 105 BLK_MQ_RQ_QUEUE_BUSY = 1, /* requeue IO for later */ 106 BLK_MQ_RQ_QUEUE_ERROR = 2, /* end IO with error */ 107 108 BLK_MQ_F_SHOULD_MERGE = 1 << 0, 109 BLK_MQ_F_SHOULD_SORT = 1 << 1, 110 BLK_MQ_F_SHOULD_IPI = 1 << 2, 111 112 BLK_MQ_S_STOPPED = 0, 113 114 BLK_MQ_MAX_DEPTH = 2048, 115}; 116 117struct request_queue *blk_mq_init_queue(struct blk_mq_reg *, void *); 118int blk_mq_register_disk(struct gendisk *); 119void blk_mq_unregister_disk(struct gendisk *); 120int blk_mq_init_commands(struct request_queue *, int (*init)(void *data, struct blk_mq_hw_ctx *, struct request *, unsigned int), void *data); 121void blk_mq_free_commands(struct request_queue *, void (*free)(void *data, struct blk_mq_hw_ctx *, struct request *, unsigned int), void *data); 122 123void blk_mq_flush_plug_list(struct blk_plug *plug, bool from_schedule); 124 125void blk_mq_insert_request(struct request_queue *, struct request *, 126 bool, bool); 127void blk_mq_run_queues(struct request_queue *q, bool async); 128void blk_mq_free_request(struct request *rq); 129bool blk_mq_can_queue(struct blk_mq_hw_ctx *); 130struct request *blk_mq_alloc_request(struct request_queue *q, int rw, gfp_t gfp); 131struct request *blk_mq_alloc_reserved_request(struct request_queue *q, int rw, gfp_t gfp); 132struct request *blk_mq_rq_from_tag(struct request_queue *q, unsigned int tag); 133 134struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *, const int ctx_index); 135struct blk_mq_hw_ctx *blk_mq_alloc_single_hw_queue(struct blk_mq_reg *, unsigned int); 136void blk_mq_free_single_hw_queue(struct blk_mq_hw_ctx *, unsigned int); 137 138void blk_mq_end_io(struct request *rq, int error); 139 140void blk_mq_complete_request(struct request *rq); 141 142void blk_mq_stop_hw_queue(struct blk_mq_hw_ctx *hctx); 143void blk_mq_start_hw_queue(struct blk_mq_hw_ctx *hctx); 144void blk_mq_stop_hw_queues(struct request_queue *q); 145void blk_mq_start_stopped_hw_queues(struct request_queue *q); 146 147/* 148 * Driver command data is immediately after the request. So subtract request 149 * size to get back to the original request. 150 */ 151static inline struct request *blk_mq_rq_from_pdu(void *pdu) 152{ 153 return pdu - sizeof(struct request); 154} 155static inline void *blk_mq_rq_to_pdu(struct request *rq) 156{ 157 return (void *) rq + sizeof(*rq); 158} 159 160static inline struct request *blk_mq_tag_to_rq(struct blk_mq_hw_ctx *hctx, 161 unsigned int tag) 162{ 163 return hctx->rqs[tag]; 164} 165 166#define queue_for_each_hw_ctx(q, hctx, i) \ 167 for ((i) = 0; (i) < (q)->nr_hw_queues && \ 168 ({ hctx = (q)->queue_hw_ctx[i]; 1; }); (i)++) 169 170#define queue_for_each_ctx(q, ctx, i) \ 171 for ((i) = 0; (i) < (q)->nr_queues && \ 172 ({ ctx = per_cpu_ptr((q)->queue_ctx, (i)); 1; }); (i)++) 173 174#define hctx_for_each_ctx(hctx, ctx, i) \ 175 for ((i) = 0; (i) < (hctx)->nr_ctx && \ 176 ({ ctx = (hctx)->ctxs[(i)]; 1; }); (i)++) 177 178#define blk_ctx_sum(q, sum) \ 179({ \ 180 struct blk_mq_ctx *__x; \ 181 unsigned int __ret = 0, __i; \ 182 \ 183 queue_for_each_ctx((q), __x, __i) \ 184 __ret += sum; \ 185 __ret; \ 186}) 187 188#endif 189