dm_pcache.h

 1/* SPDX-License-Identifier: GPL-2.0-or-later */
 2#ifndef _DM_PCACHE_H
 3#define _DM_PCACHE_H
 4#include <linux/device-mapper.h>
 5
 6#include "../dm-core.h"
 7
 8#define CACHE_DEV_TO_PCACHE(cache_dev)		(container_of(cache_dev, struct dm_pcache, cache_dev))
 9#define BACKING_DEV_TO_PCACHE(backing_dev)	(container_of(backing_dev, struct dm_pcache, backing_dev))
10#define CACHE_TO_PCACHE(cache)			(container_of(cache, struct dm_pcache, cache))
11
12#define PCACHE_STATE_RUNNING			1
13#define PCACHE_STATE_STOPPING			2
14
15struct pcache_cache_dev;
16struct pcache_backing_dev;
17struct pcache_cache;
18struct pcache_cache_options;
19struct dm_pcache {
20	struct dm_target *ti;
21	struct pcache_cache_dev cache_dev;
22	struct pcache_backing_dev backing_dev;
23	struct pcache_cache cache;
24	struct pcache_cache_options opts;
25
26	spinlock_t			defered_req_list_lock;
27	struct list_head		defered_req_list;
28	struct workqueue_struct		*task_wq;
29
30	struct work_struct		defered_req_work;
31
32	atomic_t			state;
33	atomic_t			inflight_reqs;
34	wait_queue_head_t		inflight_wq;
35};
36
37static inline bool pcache_is_stopping(struct dm_pcache *pcache)
38{
39	return (atomic_read(&pcache->state) == PCACHE_STATE_STOPPING);
40}
41
42#define pcache_dev_err(pcache, fmt, ...)							\
43	pcache_err("%s " fmt, pcache->ti->table->md->name, ##__VA_ARGS__)
44#define pcache_dev_info(pcache, fmt, ...)							\
45	pcache_info("%s " fmt, pcache->ti->table->md->name, ##__VA_ARGS__)
46#define pcache_dev_debug(pcache, fmt, ...)							\
47	pcache_debug("%s " fmt, pcache->ti->table->md->name, ##__VA_ARGS__)
48
49struct pcache_request {
50	struct dm_pcache	*pcache;
51	struct bio		*bio;
52
53	u64			off;
54	u32			data_len;
55
56	struct kref		ref;
57	int			ret;
58
59	struct list_head	list_node;
60};
61
62void pcache_req_get(struct pcache_request *pcache_req);
63void pcache_req_put(struct pcache_request *pcache_req, int ret);
64
65void pcache_defer_reqs_kick(struct dm_pcache *pcache);
66
67#endif /* _DM_PCACHE_H */