block/blk-mq-tag.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef INT_BLK_MQ_TAG_H
   3 #define INT_BLK_MQ_TAG_H
   4
   5 #include "blk-mq.h"
   6
   7 /*
   8  * Tag address space map.
   9  */
  10 struct blk_mq_tags {
  11         unsigned int nr_tags;
  12         unsigned int nr_reserved_tags;
  13
  14         atomic_t active_queues;
  15
  16         struct sbitmap_queue bitmap_tags;
  17         struct sbitmap_queue breserved_tags;
  18
  19         struct request **rqs;
  20         struct request **static_rqs;
  21         struct list_head page_list;
  22 };
  23
  24
  25 extern struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags, unsigned int reserved_tags, int node, int alloc_policy);
  26 extern void blk_mq_free_tags(struct blk_mq_tags *tags);
  27
  28 extern unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data);
  29 extern void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, struct blk_mq_tags *tags,
  30                            struct blk_mq_ctx *ctx, unsigned int tag);
  31 extern int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
  32                                         struct blk_mq_tags **tags,
  33                                         unsigned int depth, bool can_grow);
  34 extern void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool);
  35 void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
  36                 void *priv);
  37
  38 static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt,
  39                                                  struct blk_mq_hw_ctx *hctx)
  40 {
  41         if (!hctx)
  42                 return &bt->ws[0];
  43         return sbq_wait_ptr(bt, &hctx->wait_index);
  44 }
  45
  46 enum {
  47         BLK_MQ_TAG_FAIL         = -1U,
  48         BLK_MQ_TAG_MIN          = 1,
  49         BLK_MQ_TAG_MAX          = BLK_MQ_TAG_FAIL - 1,
  50 };
  51
  52 extern bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *);
  53 extern void __blk_mq_tag_idle(struct blk_mq_hw_ctx *);
  54
  55 static inline bool blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx)
  56 {
  57         if (!(hctx->flags & BLK_MQ_F_TAG_SHARED))
  58                 return false;
  59
  60         return __blk_mq_tag_busy(hctx);
  61 }
  62
  63 static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx)
  64 {
  65         if (!(hctx->flags & BLK_MQ_F_TAG_SHARED))
  66                 return;
  67
  68         __blk_mq_tag_idle(hctx);
  69 }
  70
  71 /*
  72  * This helper should only be used for flush request to share tag
  73  * with the request cloned from, and both the two requests can't be
  74  * in flight at the same time. The caller has to make sure the tag
  75  * can't be freed.
  76  */
  77 static inline void blk_mq_tag_set_rq(struct blk_mq_hw_ctx *hctx,
  78                 unsigned int tag, struct request *rq)
  79 {
  80         hctx->tags->rqs[tag] = rq;
  81 }
  82
  83 static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags,
  84                                           unsigned int tag)
  85 {
  86         return tag < tags->nr_reserved_tags;
  87 }
  88
  89 #endif