LXR linux/block/blk-mq-tag.h

   1#ifndef INT_BLK_MQ_TAG_H
   2#define INT_BLK_MQ_TAG_H
   3
   4#include "blk-mq.h"
   5
   6/*
   7 * Tag address space map.
   8 */
   9#ifdef __GENKSYMS__
  10struct blk_mq_tags;
  11#else
  12struct blk_mq_tags {
  13        unsigned int nr_tags;
  14        unsigned int nr_reserved_tags;
  15
  16        atomic_t active_queues;
  17
  18        struct sbitmap_queue bitmap_tags;
  19        struct sbitmap_queue breserved_tags;
  20
  21        struct request **rqs;
  22        struct request **static_rqs;
  23        struct list_head page_list;
  24};
  25#endif
  26
  27
  28extern struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags, unsigned int reserved_tags, int node, int alloc_policy);
  29extern void blk_mq_free_tags(struct blk_mq_tags *tags);
  30
  31extern unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data);
  32extern void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, struct blk_mq_tags *tags,
  33                           struct blk_mq_ctx *ctx, unsigned int tag);
  34extern bool blk_mq_has_free_tags(struct blk_mq_tags *tags);
  35extern int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
  36                                        struct blk_mq_tags **tags,
  37                                        unsigned int depth, bool can_grow);
  38extern void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool);
  39void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
  40                void *priv);
  41
  42static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt,
  43                                                 struct blk_mq_hw_ctx *hctx)
  44{
  45        if (!hctx)
  46                return &bt->ws[0];
  47        return sbq_wait_ptr(bt, &hctx->wait_index);
  48}
  49
  50enum {
  51        BLK_MQ_TAG_CACHE_MIN    = 1,
  52        BLK_MQ_TAG_CACHE_MAX    = 64,
  53};
  54
  55enum {
  56        BLK_MQ_TAG_FAIL         = -1U,
  57        BLK_MQ_TAG_MIN          = BLK_MQ_TAG_CACHE_MIN,
  58        BLK_MQ_TAG_MAX          = BLK_MQ_TAG_FAIL - 1,
  59};
  60
  61extern bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *);
  62extern void __blk_mq_tag_idle(struct blk_mq_hw_ctx *);
  63
  64static inline bool blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx)
  65{
  66        if (!(hctx->flags & BLK_MQ_F_TAG_SHARED))
  67                return false;
  68
  69        return __blk_mq_tag_busy(hctx);
  70}
  71
  72static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx)
  73{
  74        if (!(hctx->flags & BLK_MQ_F_TAG_SHARED))
  75                return;
  76
  77        __blk_mq_tag_idle(hctx);
  78}
  79
  80/*
  81 * This helper should only be used for flush request to share tag
  82 * with the request cloned from, and both the two requests can't be
  83 * in flight at the same time. The caller has to make sure the tag
  84 * can't be freed.
  85 */
  86static inline void blk_mq_tag_set_rq(struct blk_mq_hw_ctx *hctx,
  87                unsigned int tag, struct request *rq)
  88{
  89        hctx->tags->rqs[tag] = rq;
  90}
  91
  92static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags,
  93                                          unsigned int tag)
  94{
  95        return tag < tags->nr_reserved_tags;
  96}
  97
  98#endif
  99