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 <linux/vmalloc.h>
11#include "dm-cache-policy.h"
12
13/*----------------------------------------------------------------*/
14
15static inline int policy_lookup(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t *cblock,
16 int data_dir, bool fast_copy, bool *background_queued)
17{
18 return p->lookup(p, oblock, cblock, data_dir, fast_copy, background_queued);
19}
20
21static inline int policy_lookup_with_work(struct dm_cache_policy *p,
22 dm_oblock_t oblock, dm_cblock_t *cblock,
23 int data_dir, bool fast_copy,
24 struct policy_work **work)
25{
26 if (!p->lookup_with_work) {
27 *work = NULL;
28 return p->lookup(p, oblock, cblock, data_dir, fast_copy, NULL);
29 }
30
31 return p->lookup_with_work(p, oblock, cblock, data_dir, fast_copy, work);
32}
33
34static inline int policy_get_background_work(struct dm_cache_policy *p,
35 bool idle, struct policy_work **result)
36{
37 return p->get_background_work(p, idle, result);
38}
39
40static inline void policy_complete_background_work(struct dm_cache_policy *p,
41 struct policy_work *work,
42 bool success)
43{
44 return p->complete_background_work(p, work, success);
45}
46
47static inline void policy_set_dirty(struct dm_cache_policy *p, dm_cblock_t cblock)
48{
49 p->set_dirty(p, cblock);
50}
51
52static inline void policy_clear_dirty(struct dm_cache_policy *p, dm_cblock_t cblock)
53{
54 p->clear_dirty(p, cblock);
55}
56
57static inline int policy_load_mapping(struct dm_cache_policy *p,
58 dm_oblock_t oblock, dm_cblock_t cblock,
59 bool dirty, uint32_t hint, bool hint_valid)
60{
61 return p->load_mapping(p, oblock, cblock, dirty, hint, hint_valid);
62}
63
64static inline int policy_invalidate_mapping(struct dm_cache_policy *p,
65 dm_cblock_t cblock)
66{
67 return p->invalidate_mapping(p, cblock);
68}
69
70static inline uint32_t policy_get_hint(struct dm_cache_policy *p,
71 dm_cblock_t cblock)
72{
73 return p->get_hint ? p->get_hint(p, cblock) : 0;
74}
75
76static inline dm_cblock_t policy_residency(struct dm_cache_policy *p)
77{
78 return p->residency(p);
79}
80
81static inline void policy_tick(struct dm_cache_policy *p, bool can_block)
82{
83 if (p->tick)
84 return p->tick(p, can_block);
85}
86
87static inline int policy_emit_config_values(struct dm_cache_policy *p, char *result,
88 unsigned maxlen, ssize_t *sz_ptr)
89{
90 ssize_t sz = *sz_ptr;
91 if (p->emit_config_values)
92 return p->emit_config_values(p, result, maxlen, sz_ptr);
93
94 DMEMIT("0 ");
95 *sz_ptr = sz;
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
105static inline void policy_allow_migrations(struct dm_cache_policy *p, bool allow)
106{
107 return p->allow_migrations(p, allow);
108}
109
110/*----------------------------------------------------------------*/
111
112/*
113 * Some utility functions commonly used by policies and the core target.
114 */
115static inline size_t bitset_size_in_bytes(unsigned nr_entries)
116{
117 return sizeof(unsigned long) * dm_div_up(nr_entries, BITS_PER_LONG);
118}
119
120static inline unsigned long *alloc_bitset(unsigned nr_entries)
121{
122 size_t s = bitset_size_in_bytes(nr_entries);
123 return vzalloc(s);
124}
125
126static inline void clear_bitset(void *bitset, unsigned nr_entries)
127{
128 size_t s = bitset_size_in_bytes(nr_entries);
129 memset(bitset, 0, s);
130}
131
132static inline void free_bitset(unsigned long *bits)
133{
134 vfree(bits);
135}
136
137/*----------------------------------------------------------------*/
138
139/*
140 * Creates a new cache policy given a policy name, a cache size, an origin size and the block size.
141 */
142struct dm_cache_policy *dm_cache_policy_create(const char *name, dm_cblock_t cache_size,
143 sector_t origin_size, sector_t block_size);
144
145/*
146 * Destroys the policy. This drops references to the policy module as well
147 * as calling it's destroy method. So always use this rather than calling
148 * the policy->destroy method directly.
149 */
150void dm_cache_policy_destroy(struct dm_cache_policy *p);
151
152/*
153 * In case we've forgotten.
154 */
155const char *dm_cache_policy_get_name(struct dm_cache_policy *p);
156
157const unsigned *dm_cache_policy_get_version(struct dm_cache_policy *p);
158
159size_t dm_cache_policy_get_hint_size(struct dm_cache_policy *p);
160
161/*----------------------------------------------------------------*/
162
163#endif /* DM_CACHE_POLICY_INTERNAL_H */
164