1 #ifndef INT_BLK_MQ_TAG_H
2 #define INT_BLK_MQ_TAG_H
3
4 #include "blk-mq.h"
5
6 enum {
7 BT_WAIT_QUEUES = 8,
8 BT_WAIT_BATCH = 8,
9 };
10
11 struct bt_wait_state {
12 atomic_t wait_cnt;
13 wait_queue_head_t wait;
14 } ____cacheline_aligned_in_smp;
15
16 #define TAG_TO_INDEX(bt, tag) ((tag) >> (bt)->bits_per_word)
17 #define TAG_TO_BIT(bt, tag) ((tag) & ((1 << (bt)->bits_per_word) - 1))
18
19 struct blk_mq_bitmap_tags {
20 unsigned int depth;
21 unsigned int wake_cnt;
22 unsigned int bits_per_word;
23
24 unsigned int map_nr;
25 struct blk_align_bitmap *map;
26
27 atomic_t wake_index;
28 struct bt_wait_state *bs;
29 };
30
31 /*
32 * Tag address space map.
33 */
34 struct blk_mq_tags {
35 unsigned int nr_tags;
36 unsigned int nr_reserved_tags;
37
38 atomic_t active_queues;
39
40 struct blk_mq_bitmap_tags bitmap_tags;
41 struct blk_mq_bitmap_tags breserved_tags;
42
43 struct request **rqs;
44 struct list_head page_list;
45 };
46
47
48 extern struct blk_mq_tags *blk_mq_init_tags(unsigned int nr_tags, unsigned int reserved_tags, int node);
49 extern void blk_mq_free_tags(struct blk_mq_tags *tags);
50
51 extern unsigned int blk_mq_get_tag(struct blk_mq_alloc_data *data);
52 extern void blk_mq_put_tag(struct blk_mq_hw_ctx *hctx, unsigned int tag, unsigned int *last_tag);
53 extern bool blk_mq_has_free_tags(struct blk_mq_tags *tags);
54 extern ssize_t blk_mq_tag_sysfs_show(struct blk_mq_tags *tags, char *page);
55 extern void blk_mq_tag_init_last_tag(struct blk_mq_tags *tags, unsigned int *last_tag);
56 extern int blk_mq_tag_update_depth(struct blk_mq_tags *tags, unsigned int depth);
57
58 enum {
59 BLK_MQ_TAG_CACHE_MIN = 1,
60 BLK_MQ_TAG_CACHE_MAX = 64,
61 };
62
63 enum {
64 BLK_MQ_TAG_FAIL = -1U,
65 BLK_MQ_TAG_MIN = BLK_MQ_TAG_CACHE_MIN,
66 BLK_MQ_TAG_MAX = BLK_MQ_TAG_FAIL - 1,
67 };
68
69 extern bool __blk_mq_tag_busy(struct blk_mq_hw_ctx *);
70 extern void __blk_mq_tag_idle(struct blk_mq_hw_ctx *);
71
blk_mq_tag_busy(struct blk_mq_hw_ctx * hctx)72 static inline bool blk_mq_tag_busy(struct blk_mq_hw_ctx *hctx)
73 {
74 if (!(hctx->flags & BLK_MQ_F_TAG_SHARED))
75 return false;
76
77 return __blk_mq_tag_busy(hctx);
78 }
79
blk_mq_tag_idle(struct blk_mq_hw_ctx * hctx)80 static inline void blk_mq_tag_idle(struct blk_mq_hw_ctx *hctx)
81 {
82 if (!(hctx->flags & BLK_MQ_F_TAG_SHARED))
83 return;
84
85 __blk_mq_tag_idle(hctx);
86 }
87
88 /*
89 * This helper should only be used for flush request to share tag
90 * with the request cloned from, and both the two requests can't be
91 * in flight at the same time. The caller has to make sure the tag
92 * can't be freed.
93 */
blk_mq_tag_set_rq(struct blk_mq_hw_ctx * hctx,unsigned int tag,struct request * rq)94 static inline void blk_mq_tag_set_rq(struct blk_mq_hw_ctx *hctx,
95 unsigned int tag, struct request *rq)
96 {
97 hctx->tags->rqs[tag] = rq;
98 }
99
100 #endif
101