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 bool blk_mq_has_free_tags(struct blk_mq_tags *tags);
32 extern 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);
35 extern void blk_mq_tag_wakeup_all(struct blk_mq_tags *tags, bool);
36 void blk_mq_queue_tag_busy_iter(struct request_queue *q, busy_iter_fn *fn,
37 		void *priv);
38 
bt_wait_ptr(struct sbitmap_queue * bt,struct blk_mq_hw_ctx * hctx)39 static 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 
47 enum {
48 	BLK_MQ_TAG_FAIL		= -1U,
49 	BLK_MQ_TAG_MIN		= 1,
50 	BLK_MQ_TAG_MAX		= BLK_MQ_TAG_FAIL - 1,
51 };
52 
53 extern bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *);
54 extern void __blk_mq_tag_idle(struct blk_mq_hw_ctx *);
55 
blk_mq_tag_busy(struct blk_mq_hw_ctx * hctx)56 static 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 
blk_mq_tag_idle(struct blk_mq_hw_ctx * hctx)64 static 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  */
blk_mq_tag_set_rq(struct blk_mq_hw_ctx * hctx,unsigned int tag,struct request * rq)78 static 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 
blk_mq_tag_is_reserved(struct blk_mq_tags * tags,unsigned int tag)84 static 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
91