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#include "blk-mq-tag.h"
   7
   8struct blk_mq_tag_set;
   9
  10struct blk_mq_ctxs {
  11        struct kobject kobj;
  12        struct blk_mq_ctx __percpu      *queue_ctx;
  13};
  14
  15/**
  16 * struct blk_mq_ctx - State for a software queue facing the submitting CPUs
  17 */
  18struct blk_mq_ctx {
  19        struct {
  20                spinlock_t              lock;
  21                struct list_head        rq_lists[HCTX_MAX_TYPES];
  22        } ____cacheline_aligned_in_smp;
  23
  24        unsigned int            cpu;
  25        unsigned short          index_hw[HCTX_MAX_TYPES];
  26        struct blk_mq_hw_ctx    *hctxs[HCTX_MAX_TYPES];
  27
  28        /* incremented at dispatch time */
  29        unsigned long           rq_dispatched[2];
  30        unsigned long           rq_merged;
  31
  32        /* incremented at completion time */
  33        unsigned long           ____cacheline_aligned_in_smp rq_completed[2];
  34
  35        struct request_queue    *queue;
  36        struct blk_mq_ctxs      *ctxs;
  37        struct kobject          kobj;
  38} ____cacheline_aligned_in_smp;
  39
  40void blk_mq_exit_queue(struct request_queue *q);
  41int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
  42void blk_mq_wake_waiters(struct request_queue *q);
  43bool blk_mq_dispatch_rq_list(struct request_queue *, struct list_head *, bool);
  44void blk_mq_add_to_requeue_list(struct request *rq, bool at_head,
  45                                bool kick_requeue_list);
  46void blk_mq_flush_busy_ctxs(struct blk_mq_hw_ctx *hctx, struct list_head *list);
  47bool blk_mq_get_driver_tag(struct request *rq);
  48struct request *blk_mq_dequeue_from_ctx(struct blk_mq_hw_ctx *hctx,
  49                                        struct blk_mq_ctx *start);
  50
  51/*
  52 * Internal helpers for allocating/freeing the request map
  53 */
  54void blk_mq_free_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
  55                     unsigned int hctx_idx);
  56void blk_mq_free_rq_map(struct blk_mq_tags *tags);
  57struct blk_mq_tags *blk_mq_alloc_rq_map(struct blk_mq_tag_set *set,
  58                                        unsigned int hctx_idx,
  59                                        unsigned int nr_tags,
  60                                        unsigned int reserved_tags);
  61int blk_mq_alloc_rqs(struct blk_mq_tag_set *set, struct blk_mq_tags *tags,
  62                     unsigned int hctx_idx, unsigned int depth);
  63
  64/*
  65 * Internal helpers for request insertion into sw queues
  66 */
  67void __blk_mq_insert_request(struct blk_mq_hw_ctx *hctx, struct request *rq,
  68                                bool at_head);
  69void blk_mq_request_bypass_insert(struct request *rq, bool run_queue);
  70void blk_mq_insert_requests(struct blk_mq_hw_ctx *hctx, struct blk_mq_ctx *ctx,
  71                                struct list_head *list);
  72
  73/* Used by blk_insert_cloned_request() to issue request directly */
  74blk_status_t blk_mq_request_issue_directly(struct request *rq, bool last);
  75void blk_mq_try_issue_list_directly(struct blk_mq_hw_ctx *hctx,
  76                                    struct list_head *list);
  77
  78/*
  79 * CPU -> queue mappings
  80 */
  81extern int blk_mq_hw_queue_to_node(struct blk_mq_queue_map *qmap, unsigned int);
  82
  83/*
  84 * blk_mq_map_queue_type() - map (hctx_type,cpu) to hardware queue
  85 * @q: request queue
  86 * @type: the hctx type index
  87 * @cpu: CPU
  88 */
  89static inline struct blk_mq_hw_ctx *blk_mq_map_queue_type(struct request_queue *q,
  90                                                          enum hctx_type type,
  91                                                          unsigned int cpu)
  92{
  93        return q->queue_hw_ctx[q->tag_set->map[type].mq_map[cpu]];
  94}
  95
  96/*
  97 * blk_mq_map_queue() - map (cmd_flags,type) to hardware queue
  98 * @q: request queue
  99 * @flags: request command flags
 100 * @cpu: cpu ctx
 101 */
 102static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
 103                                                     unsigned int flags,
 104                                                     struct blk_mq_ctx *ctx)
 105{
 106        enum hctx_type type = HCTX_TYPE_DEFAULT;
 107
 108        /*
 109         * The caller ensure that if REQ_HIPRI, poll must be enabled.
 110         */
 111        if (flags & REQ_HIPRI)
 112                type = HCTX_TYPE_POLL;
 113        else if ((flags & REQ_OP_MASK) == REQ_OP_READ)
 114                type = HCTX_TYPE_READ;
 115        
 116        return ctx->hctxs[type];
 117}
 118
 119/*
 120 * sysfs helpers
 121 */
 122extern void blk_mq_sysfs_init(struct request_queue *q);
 123extern void blk_mq_sysfs_deinit(struct request_queue *q);
 124extern int __blk_mq_register_dev(struct device *dev, struct request_queue *q);
 125extern int blk_mq_sysfs_register(struct request_queue *q);
 126extern void blk_mq_sysfs_unregister(struct request_queue *q);
 127extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
 128
 129void blk_mq_release(struct request_queue *q);
 130
 131/**
 132 * blk_mq_rq_state() - read the current MQ_RQ_* state of a request
 133 * @rq: target request.
 134 */
 135static inline enum mq_rq_state blk_mq_rq_state(struct request *rq)
 136{
 137        return READ_ONCE(rq->state);
 138}
 139
 140static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
 141                                           unsigned int cpu)
 142{
 143        return per_cpu_ptr(q->queue_ctx, cpu);
 144}
 145
 146/*
 147 * This assumes per-cpu software queueing queues. They could be per-node
 148 * as well, for instance. For now this is hardcoded as-is. Note that we don't
 149 * care about preemption, since we know the ctx's are persistent. This does
 150 * mean that we can't rely on ctx always matching the currently running CPU.
 151 */
 152static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
 153{
 154        return __blk_mq_get_ctx(q, get_cpu());
 155}
 156
 157static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
 158{
 159        put_cpu();
 160}
 161
 162struct blk_mq_alloc_data {
 163        /* input parameter */
 164        struct request_queue *q;
 165        blk_mq_req_flags_t flags;
 166        unsigned int shallow_depth;
 167        unsigned int cmd_flags;
 168
 169        /* input & output parameter */
 170        struct blk_mq_ctx *ctx;
 171        struct blk_mq_hw_ctx *hctx;
 172};
 173
 174static inline struct blk_mq_tags *blk_mq_tags_from_data(struct blk_mq_alloc_data *data)
 175{
 176        if (data->flags & BLK_MQ_REQ_INTERNAL)
 177                return data->hctx->sched_tags;
 178
 179        return data->hctx->tags;
 180}
 181
 182static inline bool blk_mq_hctx_stopped(struct blk_mq_hw_ctx *hctx)
 183{
 184        return test_bit(BLK_MQ_S_STOPPED, &hctx->state);
 185}
 186
 187static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
 188{
 189        return hctx->nr_ctx && hctx->tags;
 190}
 191
 192unsigned int blk_mq_in_flight(struct request_queue *q, struct hd_struct *part);
 193void blk_mq_in_flight_rw(struct request_queue *q, struct hd_struct *part,
 194                         unsigned int inflight[2]);
 195
 196static inline void blk_mq_put_dispatch_budget(struct blk_mq_hw_ctx *hctx)
 197{
 198        struct request_queue *q = hctx->queue;
 199
 200        if (q->mq_ops->put_budget)
 201                q->mq_ops->put_budget(hctx);
 202}
 203
 204static inline bool blk_mq_get_dispatch_budget(struct blk_mq_hw_ctx *hctx)
 205{
 206        struct request_queue *q = hctx->queue;
 207
 208        if (q->mq_ops->get_budget)
 209                return q->mq_ops->get_budget(hctx);
 210        return true;
 211}
 212
 213static inline void __blk_mq_put_driver_tag(struct blk_mq_hw_ctx *hctx,
 214                                           struct request *rq)
 215{
 216        blk_mq_put_tag(hctx, hctx->tags, rq->mq_ctx, rq->tag);
 217        rq->tag = -1;
 218
 219        if (rq->rq_flags & RQF_MQ_INFLIGHT) {
 220                rq->rq_flags &= ~RQF_MQ_INFLIGHT;
 221                atomic_dec(&hctx->nr_active);
 222        }
 223}
 224
 225static inline void blk_mq_put_driver_tag(struct request *rq)
 226{
 227        if (rq->tag == -1 || rq->internal_tag == -1)
 228                return;
 229
 230        __blk_mq_put_driver_tag(rq->mq_hctx, rq);
 231}
 232
 233static inline void blk_mq_clear_mq_map(struct blk_mq_queue_map *qmap)
 234{
 235        int cpu;
 236
 237        for_each_possible_cpu(cpu)
 238                qmap->mq_map[cpu] = 0;
 239}
 240
 241#endif
 242