xref: /linux/drivers/md/dm-pcache/dm_pcache.h (revision 55a42f78ffd386e01a5404419f8c5ded7db70a21)
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 
15 struct pcache_cache_dev;
16 struct pcache_backing_dev;
17 struct pcache_cache;
18 struct pcache_cache_options;
19 struct 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 
37 static 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 
49 struct 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 
62 void pcache_req_get(struct pcache_request *pcache_req);
63 void pcache_req_put(struct pcache_request *pcache_req, int ret);
64 
65 void pcache_defer_reqs_kick(struct dm_pcache *pcache);
66 
67 #endif /* _DM_PCACHE_H */
68