1#ifndef INT_BLK_MQ_H
2#define INT_BLK_MQ_H
3
4struct blk_mq_tag_set;
5
6struct blk_mq_ctx {
7	struct {
8		spinlock_t		lock;
9		struct list_head	rq_list;
10	}  ____cacheline_aligned_in_smp;
11
12	unsigned int		cpu;
13	unsigned int		index_hw;
14
15	unsigned int		last_tag ____cacheline_aligned_in_smp;
16
17	/* incremented at dispatch time */
18	unsigned long		rq_dispatched[2];
19	unsigned long		rq_merged;
20
21	/* incremented at completion time */
22	unsigned long		____cacheline_aligned_in_smp rq_completed[2];
23
24	struct request_queue	*queue;
25	struct kobject		kobj;
26} ____cacheline_aligned_in_smp;
27
28void __blk_mq_complete_request(struct request *rq);
29void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
30void blk_mq_freeze_queue(struct request_queue *q);
31void blk_mq_free_queue(struct request_queue *q);
32void blk_mq_clone_flush_request(struct request *flush_rq,
33		struct request *orig_rq);
34int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
35void blk_mq_wake_waiters(struct request_queue *q);
36
37/*
38 * CPU hotplug helpers
39 */
40struct blk_mq_cpu_notifier;
41void blk_mq_init_cpu_notifier(struct blk_mq_cpu_notifier *notifier,
42			      int (*fn)(void *, unsigned long, unsigned int),
43			      void *data);
44void blk_mq_register_cpu_notifier(struct blk_mq_cpu_notifier *notifier);
45void blk_mq_unregister_cpu_notifier(struct blk_mq_cpu_notifier *notifier);
46void blk_mq_cpu_init(void);
47void blk_mq_enable_hotplug(void);
48void blk_mq_disable_hotplug(void);
49
50/*
51 * CPU -> queue mappings
52 */
53extern unsigned int *blk_mq_make_queue_map(struct blk_mq_tag_set *set);
54extern int blk_mq_update_queue_map(unsigned int *map, unsigned int nr_queues);
55extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);
56
57/*
58 * sysfs helpers
59 */
60extern int blk_mq_sysfs_register(struct request_queue *q);
61extern void blk_mq_sysfs_unregister(struct request_queue *q);
62
63extern void blk_mq_rq_timed_out(struct request *req, bool reserved);
64
65void blk_mq_release(struct request_queue *q);
66
67/*
68 * Basic implementation of sparser bitmap, allowing the user to spread
69 * the bits over more cachelines.
70 */
71struct blk_align_bitmap {
72	unsigned long word;
73	unsigned long depth;
74} ____cacheline_aligned_in_smp;
75
76static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
77					   unsigned int cpu)
78{
79	return per_cpu_ptr(q->queue_ctx, cpu);
80}
81
82/*
83 * This assumes per-cpu software queueing queues. They could be per-node
84 * as well, for instance. For now this is hardcoded as-is. Note that we don't
85 * care about preemption, since we know the ctx's are persistent. This does
86 * mean that we can't rely on ctx always matching the currently running CPU.
87 */
88static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
89{
90	return __blk_mq_get_ctx(q, get_cpu());
91}
92
93static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
94{
95	put_cpu();
96}
97
98struct blk_mq_alloc_data {
99	/* input parameter */
100	struct request_queue *q;
101	gfp_t gfp;
102	bool reserved;
103
104	/* input & output parameter */
105	struct blk_mq_ctx *ctx;
106	struct blk_mq_hw_ctx *hctx;
107};
108
109static inline void blk_mq_set_alloc_data(struct blk_mq_alloc_data *data,
110		struct request_queue *q, gfp_t gfp, bool reserved,
111		struct blk_mq_ctx *ctx,
112		struct blk_mq_hw_ctx *hctx)
113{
114	data->q = q;
115	data->gfp = gfp;
116	data->reserved = reserved;
117	data->ctx = ctx;
118	data->hctx = hctx;
119}
120
121static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
122{
123	return hctx->nr_ctx && hctx->tags;
124}
125
126#endif
127