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 */
10struct 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
25extern struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags, unsigned int reserved_tags, int node, int alloc_policy);
26extern void blk_mq_free_tags(struct blk_mq_tags *tags);
27
28extern unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data);
29extern 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);
31extern bool blk_mq_has_free_tags(struct blk_mq_tags *tags);
32extern int blk_mq_tag_update_depth(struct blk_mq_hw_ctx *hctx,
33					struct blk_mq_tags **tags,
34					unsigned int depth, bool can_grow);
35extern void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool);
36void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
37		void *priv);
38
39static inline struct sbq_wait_state *bt_wait_ptr(struct sbitmap_queue *bt,
40						 struct blk_mq_hw_ctx *hctx)
41{
42	if (!hctx)
43		return &bt->ws[0];
44	return sbq_wait_ptr(bt, &hctx->wait_index);
45}
46
47enum {
48	BLK_MQ_TAG_FAIL		= -1U,
49	BLK_MQ_TAG_MIN		= 1,
50	BLK_MQ_TAG_MAX		= BLK_MQ_TAG_FAIL - 1,
51};
52
53extern bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *);
54extern void __blk_mq_tag_idle(struct blk_mq_hw_ctx *);
55
56static inline bool blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx)
57{
58	if (!(hctx->flags & BLK_MQ_F_TAG_SHARED))
59		return false;
60
61	return __blk_mq_tag_busy(hctx);
62}
63
64static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx)
65{
66	if (!(hctx->flags & BLK_MQ_F_TAG_SHARED))
67		return;
68
69	__blk_mq_tag_idle(hctx);
70}
71
72/*
73 * This helper should only be used for flush request to share tag
74 * with the request cloned from, and both the two requests can't be
75 * in flight at the same time. The caller has to make sure the tag
76 * can't be freed.
77 */
78static inline void blk_mq_tag_set_rq(struct blk_mq_hw_ctx *hctx,
79		unsigned int tag, struct request *rq)
80{
81	hctx->tags->rqs[tag] = rq;
82}
83
84static inline bool blk_mq_tag_is_reserved(struct blk_mq_tags *tags,
85					  unsigned int tag)
86{
87	return tag < tags->nr_reserved_tags;
88}
89
90#endif