1/*
2 * Copyright (C) 2012 Red Hat. All rights reserved.
3 *
4 * This file is released under the GPL.
5 */
6
7#ifndef DM_CACHE_POLICY_INTERNAL_H
8#define DM_CACHE_POLICY_INTERNAL_H
9
10#include "dm-cache-policy.h"
11
12/*----------------------------------------------------------------*/
13
14/*
15 * Little inline functions that simplify calling the policy methods.
16 */
17static inline int policy_map(struct dm_cache_policy *p, dm_oblock_t oblock,
18			     bool can_block, bool can_migrate, bool discarded_oblock,
19			     struct bio *bio, struct policy_locker *locker,
20			     struct policy_result *result)
21{
22	return p->map(p, oblock, can_block, can_migrate, discarded_oblock, bio, locker, result);
23}
24
25static inline int policy_lookup(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t *cblock)
26{
27	BUG_ON(!p->lookup);
28	return p->lookup(p, oblock, cblock);
29}
30
31static inline void policy_set_dirty(struct dm_cache_policy *p, dm_oblock_t oblock)
32{
33	if (p->set_dirty)
34		p->set_dirty(p, oblock);
35}
36
37static inline void policy_clear_dirty(struct dm_cache_policy *p, dm_oblock_t oblock)
38{
39	if (p->clear_dirty)
40		p->clear_dirty(p, oblock);
41}
42
43static inline int policy_load_mapping(struct dm_cache_policy *p,
44				      dm_oblock_t oblock, dm_cblock_t cblock,
45				      uint32_t hint, bool hint_valid)
46{
47	return p->load_mapping(p, oblock, cblock, hint, hint_valid);
48}
49
50static inline int policy_walk_mappings(struct dm_cache_policy *p,
51				      policy_walk_fn fn, void *context)
52{
53	return p->walk_mappings ? p->walk_mappings(p, fn, context) : 0;
54}
55
56static inline int policy_writeback_work(struct dm_cache_policy *p,
57					dm_oblock_t *oblock,
58					dm_cblock_t *cblock)
59{
60	return p->writeback_work ? p->writeback_work(p, oblock, cblock) : -ENOENT;
61}
62
63static inline void policy_remove_mapping(struct dm_cache_policy *p, dm_oblock_t oblock)
64{
65	p->remove_mapping(p, oblock);
66}
67
68static inline int policy_remove_cblock(struct dm_cache_policy *p, dm_cblock_t cblock)
69{
70	return p->remove_cblock(p, cblock);
71}
72
73static inline void policy_force_mapping(struct dm_cache_policy *p,
74					dm_oblock_t current_oblock, dm_oblock_t new_oblock)
75{
76	return p->force_mapping(p, current_oblock, new_oblock);
77}
78
79static inline dm_cblock_t policy_residency(struct dm_cache_policy *p)
80{
81	return p->residency(p);
82}
83
84static inline void policy_tick(struct dm_cache_policy *p)
85{
86	if (p->tick)
87		return p->tick(p);
88}
89
90static inline int policy_emit_config_values(struct dm_cache_policy *p, char *result, unsigned maxlen)
91{
92	ssize_t sz = 0;
93	if (p->emit_config_values)
94		return p->emit_config_values(p, result, maxlen);
95
96	DMEMIT("0");
97	return 0;
98}
99
100static inline int policy_set_config_value(struct dm_cache_policy *p,
101					  const char *key, const char *value)
102{
103	return p->set_config_value ? p->set_config_value(p, key, value) : -EINVAL;
104}
105
106/*----------------------------------------------------------------*/
107
108/*
109 * Creates a new cache policy given a policy name, a cache size, an origin size and the block size.
110 */
111struct dm_cache_policy *dm_cache_policy_create(const char *name, dm_cblock_t cache_size,
112					       sector_t origin_size, sector_t block_size);
113
114/*
115 * Destroys the policy.  This drops references to the policy module as well
116 * as calling it's destroy method.  So always use this rather than calling
117 * the policy->destroy method directly.
118 */
119void dm_cache_policy_destroy(struct dm_cache_policy *p);
120
121/*
122 * In case we've forgotten.
123 */
124const char *dm_cache_policy_get_name(struct dm_cache_policy *p);
125
126const unsigned *dm_cache_policy_get_version(struct dm_cache_policy *p);
127
128size_t dm_cache_policy_get_hint_size(struct dm_cache_policy *p);
129
130/*----------------------------------------------------------------*/
131
132#endif /* DM_CACHE_POLICY_INTERNAL_H */
133