path: root/block/blk-mq.h (plain)
blob: c55bcf67b9560fba32e4e53318ba149dba4320ad

1	#ifndef INT_BLK_MQ_H
2	#define INT_BLK_MQ_H
3
4	struct blk_mq_tag_set;
5
6	struct 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	/* incremented at dispatch time */
16	unsigned long rq_dispatched[2];
17	unsigned long rq_merged;
18
19	/* incremented at completion time */
20	unsigned long ____cacheline_aligned_in_smp rq_completed[2];
21
22	struct request_queue *queue;
23	struct kobject kobj;
24	} ____cacheline_aligned_in_smp;
25
26	void blk_mq_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async);
27	void blk_mq_freeze_queue(struct request_queue *q);
28	void blk_mq_free_queue(struct request_queue *q);
29	int blk_mq_update_nr_requests(struct request_queue *q, unsigned int nr);
30	void blk_mq_wake_waiters(struct request_queue *q);
31
32	/*
33	* CPU hotplug helpers
34	*/
35	void blk_mq_enable_hotplug(void);
36	void blk_mq_disable_hotplug(void);
37
38	/*
39	* CPU -> queue mappings
40	*/
41	int blk_mq_map_queues(struct blk_mq_tag_set *set);
42	extern int blk_mq_hw_queue_to_node(unsigned int *map, unsigned int);
43
44	static inline struct blk_mq_hw_ctx *blk_mq_map_queue(struct request_queue *q,
45	int cpu)
46	{
47	return q->queue_hw_ctx[q->mq_map[cpu]];
48	}
49
50	/*
51	* sysfs helpers
52	*/
53	extern void blk_mq_sysfs_init(struct request_queue *q);
54	extern int blk_mq_sysfs_register(struct request_queue *q);
55	extern void blk_mq_sysfs_unregister(struct request_queue *q);
56	extern void blk_mq_hctx_kobj_init(struct blk_mq_hw_ctx *hctx);
57
58	extern void blk_mq_rq_timed_out(struct request *req, bool reserved);
59
60	void blk_mq_release(struct request_queue *q);
61
62	static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q,
63	unsigned int cpu)
64	{
65	return per_cpu_ptr(q->queue_ctx, cpu);
66	}
67
68	/*
69	* This assumes per-cpu software queueing queues. They could be per-node
70	* as well, for instance. For now this is hardcoded as-is. Note that we don't
71	* care about preemption, since we know the ctx's are persistent. This does
72	* mean that we can't rely on ctx always matching the currently running CPU.
73	*/
74	static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q)
75	{
76	return __blk_mq_get_ctx(q, get_cpu());
77	}
78
79	static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx)
80	{
81	put_cpu();
82	}
83
84	struct blk_mq_alloc_data {
85	/* input parameter */
86	struct request_queue *q;
87	unsigned int flags;
88
89	/* input & output parameter */
90	struct blk_mq_ctx *ctx;
91	struct blk_mq_hw_ctx *hctx;
92	};
93
94	static inline void blk_mq_set_alloc_data(struct blk_mq_alloc_data *data,
95	struct request_queue *q, unsigned int flags,
96	struct blk_mq_ctx *ctx, struct blk_mq_hw_ctx *hctx)
97	{
98	data->q = q;
99	data->flags = flags;
100	data->ctx = ctx;
101	data->hctx = hctx;
102	}
103
104	static inline bool blk_mq_hw_queue_mapped(struct blk_mq_hw_ctx *hctx)
105	{
106	return hctx->nr_ctx && hctx->tags;
107	}
108
109	#endif
110