block/blk-mq.h

   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_ctx {
  11         struct {
  12                 spinlock_t              lock;
  13                 struct list_head        rq_list;
  14         }  ____cacheline_aligned_in_smp;
  15
  16         unsigned int            cpu;
  17         unsigned int            index_hw;
  18
  19         /* incremented at dispatch time */
  20         unsigned long           rq_dispatched[2];
  21         unsigned long           rq_merged;
  22
  23         /* incremented at completion time */
  24         unsigned long           ____cacheline_aligned_in_smp rq_completed[2];
  25
  26         struct request_queue    *queue;
  27         struct kobject          kobj;
  28 } ____cacheline_aligned_in_smp;
  29
  30 void blk_mq_freeze_queue(struct request_queue *q);
  31 void blk_mq_exit_queue(struct request_queue *q);
  32 int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
  33 void blk_mq_wake_waiters(struct request_queue *q);
  34 bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool);
  35 void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
  36 bool blk_mq_get_driver_tag(struct request *rq, struct blk_mq_hw_ctx **hctx,
  37                                 bool wait);
  38 struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
  39                                         struct blk_mq_ctx *start);
  40
  41 /*
  42  * Internal helpers for allocating/freeing the request map
  43  */
  44 void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
  45                      unsigned int hctx_idx);
  46 void blk_mq_free_rq_map(struct blk_mq_tags *tags);
  47 struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
  48                                         unsigned int hctx_idx,
  49                                         unsigned int nr_tags,
  50                                         unsigned int reserved_tags);
  51 int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
  52                      unsigned int hctx_idx, unsigned int depth);
  53
  54 /*
  55  * Internal helpers for request insertion into sw queues
  56  */
  57 void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
  58                                 bool at_head);
  59 void blk_mq_request_bypass_insert(struct request *rq, bool run_queue);
  60 void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
  61                                 struct list_head *list);
  62
  63 /* Used by blk_insert_cloned_request() to issue request directly */
  64 blk_status_t blk_mq_request_issue_directly(struct request *rq);
  65
  66 /*
  67  * CPU -> queue mappings
  68  */
  69 extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);
  70
  71 static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
  72                 int cpu)
  73 {
  74         return q->queue_hw_ctx[q->mq_map[cpu]];
  75 }
  76
  77 /*
  78  * sysfs helpers
  79  */
  80 extern void blk_mq_sysfs_init(struct request_queue *q);
  81 extern void blk_mq_sysfs_deinit(struct request_queue *q);
  82 extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q);
  83 extern int blk_mq_sysfs_register(struct request_queue *q);
  84 extern void blk_mq_sysfs_unregister(struct request_queue *q);
  85 extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
  86
  87 extern void blk_mq_rq_timed_out(struct request *req, bool reserved);
  88
  89 void blk_mq_release(struct request_queue *q);
  90
  91 static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
  92                                            unsigned int cpu)
  93 {
  94         return per_cpu_ptr(q->queue_ctx, cpu);
  95 }
  96
  97 /*
  98  * This assumes per-cpu software queueing queues. They could be per-node
  99  * as well, for instance. For now this is hardcoded as-is. Note that we don't
 100  * care about preemption, since we know the ctx's are persistent. This does
 101  * mean that we can't rely on ctx always matching the currently running CPU.
 102  */
 103 static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
 104 {
 105         return __blk_mq_get_ctx(q, get_cpu());
 106 }
 107
 108 static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
 109 {
 110         put_cpu();
 111 }
 112
 113 struct blk_mq_alloc_data {
 114         /* input parameter */
 115         struct request_queue *q;
 116         blk_mq_req_flags_t flags;
 117         unsigned int shallow_depth;
 118
 119         /* input & output parameter */
 120         struct blk_mq_ctx *ctx;
 121         struct blk_mq_hw_ctx *hctx;
 122 };
 123
 124 static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
 125 {
 126         if (data->flags & BLK_MQ_REQ_INTERNAL)
 127                 return data->hctx->sched_tags;
 128
 129         return data->hctx->tags;
 130 }
 131
 132 static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
 133 {
 134         return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
 135 }
 136
 137 static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
 138 {
 139         return hctx->nr_ctx && hctx->tags;
 140 }
 141
 142 void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
 143                       unsigned int inflight[2]);
 144 void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
 145                          unsigned int inflight[2]);
 146
 147 static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx)
 148 {
 149         struct request_queue *q = hctx->queue;
 150
 151         if (q->mq_ops->put_budget)
 152                 q->mq_ops->put_budget(hctx);
 153 }
 154
 155 static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx)
 156 {
 157         struct request_queue *q = hctx->queue;
 158
 159         if (q->mq_ops->get_budget)
 160                 return q->mq_ops->get_budget(hctx);
 161         return true;
 162 }
 163
 164 static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
 165                                            struct request *rq)
 166 {
 167         blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag);
 168         rq->tag = -1;
 169
 170         if (rq->rq_flags & RQF_MQ_INFLIGHT) {
 171                 rq->rq_flags &= ~RQF_MQ_INFLIGHT;
 172                 atomic_dec(&hctx->nr_active);
 173         }
 174 }
 175
 176 static inline void blk_mq_put_driver_tag_hctx(struct blk_mq_hw_ctx *hctx,
 177                                        struct request *rq)
 178 {
 179         if (rq->tag == -1 || rq->internal_tag == -1)
 180                 return;
 181
 182         __blk_mq_put_driver_tag(hctx, rq);
 183 }
 184
 185 static inline void blk_mq_put_driver_tag(struct request *rq)
 186 {
 187         struct blk_mq_hw_ctx *hctx;
 188
 189         if (rq->tag == -1 || rq->internal_tag == -1)
 190                 return;
 191
 192         hctx = blk_mq_map_queue(rq->q, rq->mq_ctx->cpu);
 193         __blk_mq_put_driver_tag(hctx, rq);
 194 }
 195
 196 #endif