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