LXR linux/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
   7struct blk_mq_tag_set;
   8
   9struct blk_mq_ctx {
  10        struct {
  11                spinlock_t              lock;
  12                struct list_head        rq_list;
  13        }  ____cacheline_aligned_in_smp;
  14
  15        unsigned int            cpu;
  16        unsigned int            index_hw;
  17
  18        /* incremented at dispatch time */
  19        unsigned long           rq_dispatched[2];
  20        unsigned long           rq_merged;
  21
  22        /* incremented at completion time */
  23        unsigned long           ____cacheline_aligned_in_smp rq_completed[2];
  24
  25        struct request_queue    *queue;
  26        struct kobject          kobj;
  27} ____cacheline_aligned_in_smp;
  28
  29void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
  30void blk_mq_freeze_queue(struct request_queue *q);
  31void blk_mq_free_queue(struct request_queue *q);
  32int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
  33void blk_mq_wake_waiters(struct request_queue *q);
  34bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *);
  35void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
  36bool blk_mq_hctx_has_pending(struct blk_mq_hw_ctx *hctx);
  37bool blk_mq_get_driver_tag(struct request *rq, struct blk_mq_hw_ctx **hctx,
  38                                bool wait);
  39
  40/*
  41 * Internal helpers for allocating/freeing the request map
  42 */
  43void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
  44                     unsigned int hctx_idx);
  45void blk_mq_free_rq_map(struct blk_mq_tags *tags);
  46struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
  47                                        unsigned int hctx_idx,
  48                                        unsigned int nr_tags,
  49                                        unsigned int reserved_tags);
  50int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
  51                     unsigned int hctx_idx, unsigned int depth);
  52
  53/*
  54 * Internal helpers for request insertion into sw queues
  55 */
  56void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
  57                                bool at_head);
  58void blk_mq_request_bypass_insert(struct request *rq);
  59void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
  60                                struct list_head *list);
  61
  62/*
  63 * CPU -> queue mappings
  64 */
  65extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);
  66
  67static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
  68                int cpu)
  69{
  70        return q->queue_hw_ctx[q->mq_map[cpu]];
  71}
  72
  73/*
  74 * sysfs helpers
  75 */
  76extern void blk_mq_sysfs_init(struct request_queue *q);
  77extern void blk_mq_sysfs_deinit(struct request_queue *q);
  78extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q);
  79extern int blk_mq_sysfs_register(struct request_queue *q);
  80extern void blk_mq_sysfs_unregister(struct request_queue *q);
  81extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
  82
  83extern void blk_mq_rq_timed_out(struct request *req, bool reserved);
  84
  85void blk_mq_release(struct request_queue *q);
  86
  87static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
  88                                           unsigned int cpu)
  89{
  90        return per_cpu_ptr(q->queue_ctx, cpu);
  91}
  92
  93/*
  94 * This assumes per-cpu software queueing queues. They could be per-node
  95 * as well, for instance. For now this is hardcoded as-is. Note that we don't
  96 * care about preemption, since we know the ctx's are persistent. This does
  97 * mean that we can't rely on ctx always matching the currently running CPU.
  98 */
  99static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
 100{
 101        return __blk_mq_get_ctx(q, get_cpu());
 102}
 103
 104static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
 105{
 106        put_cpu();
 107}
 108
 109struct blk_mq_alloc_data {
 110        /* input parameter */
 111        struct request_queue *q;
 112        unsigned int flags;
 113        unsigned int shallow_depth;
 114
 115        /* input & output parameter */
 116        struct blk_mq_ctx *ctx;
 117        struct blk_mq_hw_ctx *hctx;
 118};
 119
 120static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
 121{
 122        if (data->flags & BLK_MQ_REQ_INTERNAL)
 123                return data->hctx->sched_tags;
 124
 125        return data->hctx->tags;
 126}
 127
 128static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
 129{
 130        return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
 131}
 132
 133static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
 134{
 135        return hctx->nr_ctx && hctx->tags;
 136}
 137
 138void blk_mq_in_flight(struct request_queue *q, struct hd_struct *part,
 139                        unsigned int inflight[2]);
 140
 141#endif
 142