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  */
policy_map(struct dm_cache_policy * p,dm_oblock_t oblock,bool can_block,bool can_migrate,bool discarded_oblock,struct bio * bio,struct policy_locker * locker,struct policy_result * result)17 static 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 
policy_lookup(struct dm_cache_policy * p,dm_oblock_t oblock,dm_cblock_t * cblock)25 static 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 
policy_set_dirty(struct dm_cache_policy * p,dm_oblock_t oblock)31 static 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 
policy_clear_dirty(struct dm_cache_policy * p,dm_oblock_t oblock)37 static 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 
policy_load_mapping(struct dm_cache_policy * p,dm_oblock_t oblock,dm_cblock_t cblock,uint32_t hint,bool hint_valid)43 static 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 
policy_walk_mappings(struct dm_cache_policy * p,policy_walk_fn fn,void * context)50 static 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 
policy_writeback_work(struct dm_cache_policy * p,dm_oblock_t * oblock,dm_cblock_t * cblock)56 static 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 
policy_remove_mapping(struct dm_cache_policy * p,dm_oblock_t oblock)63 static inline void policy_remove_mapping(struct dm_cache_policy *p, dm_oblock_t oblock)
64 {
65 	p->remove_mapping(p, oblock);
66 }
67 
policy_remove_cblock(struct dm_cache_policy * p,dm_cblock_t cblock)68 static inline int policy_remove_cblock(struct dm_cache_policy *p, dm_cblock_t cblock)
69 {
70 	return p->remove_cblock(p, cblock);
71 }
72 
policy_force_mapping(struct dm_cache_policy * p,dm_oblock_t current_oblock,dm_oblock_t new_oblock)73 static 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 
policy_residency(struct dm_cache_policy * p)79 static inline dm_cblock_t policy_residency(struct dm_cache_policy *p)
80 {
81 	return p->residency(p);
82 }
83 
policy_tick(struct dm_cache_policy * p)84 static inline void policy_tick(struct dm_cache_policy *p)
85 {
86 	if (p->tick)
87 		return p->tick(p);
88 }
89 
policy_emit_config_values(struct dm_cache_policy * p,char * result,unsigned maxlen)90 static 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 
policy_set_config_value(struct dm_cache_policy * p,const char * key,const char * value)100 static 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  */
111 struct 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  */
119 void dm_cache_policy_destroy(struct dm_cache_policy *p);
120 
121 /*
122  * In case we've forgotten.
123  */
124 const char *dm_cache_policy_get_name(struct dm_cache_policy *p);
125 
126 const unsigned *dm_cache_policy_get_version(struct dm_cache_policy *p);
127 
128 size_t dm_cache_policy_get_hint_size(struct dm_cache_policy *p);
129 
130 /*----------------------------------------------------------------*/
131 
132 #endif /* DM_CACHE_POLICY_INTERNAL_H */
133