1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 * Copyright (C) 2012 Red Hat. All rights reserved.
  4 *
  5 * This file is released under the GPL.
  6 */
  7
  8#ifndef DM_CACHE_POLICY_INTERNAL_H
  9#define DM_CACHE_POLICY_INTERNAL_H
 10
 11#include <linux/vmalloc.h>
 12#include "dm-cache-policy.h"
 13
 14/*----------------------------------------------------------------*/
 15
 16static inline int policy_lookup(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t *cblock,
 17				int data_dir, bool fast_copy, bool *background_queued)
 18{
 19	return p->lookup(p, oblock, cblock, data_dir, fast_copy, background_queued);
 20}
 21
 22static inline int policy_lookup_with_work(struct dm_cache_policy *p,
 23					  dm_oblock_t oblock, dm_cblock_t *cblock,
 24					  int data_dir, bool fast_copy,
 25					  struct policy_work **work)
 26{
 27	if (!p->lookup_with_work) {
 28		*work = NULL;
 29		return p->lookup(p, oblock, cblock, data_dir, fast_copy, NULL);
 30	}
 31
 32	return p->lookup_with_work(p, oblock, cblock, data_dir, fast_copy, work);
 33}
 34
 35static inline int policy_get_background_work(struct dm_cache_policy *p,
 36					     bool idle, struct policy_work **result)
 37{
 38	return p->get_background_work(p, idle, result);
 39}
 40
 41static inline void policy_complete_background_work(struct dm_cache_policy *p,
 42						   struct policy_work *work,
 43						   bool success)
 44{
 45	return p->complete_background_work(p, work, success);
 46}
 47
 48static inline void policy_set_dirty(struct dm_cache_policy *p, dm_cblock_t cblock)
 49{
 50	p->set_dirty(p, cblock);
 51}
 52
 53static inline void policy_clear_dirty(struct dm_cache_policy *p, dm_cblock_t cblock)
 54{
 55	p->clear_dirty(p, cblock);
 56}
 57
 58static inline int policy_load_mapping(struct dm_cache_policy *p,
 59				      dm_oblock_t oblock, dm_cblock_t cblock,
 60				      bool dirty, uint32_t hint, bool hint_valid)
 61{
 62	return p->load_mapping(p, oblock, cblock, dirty, hint, hint_valid);
 63}
 64
 65static inline int policy_invalidate_mapping(struct dm_cache_policy *p,
 66					    dm_cblock_t cblock)
 67{
 68	return p->invalidate_mapping(p, cblock);
 69}
 70
 71static inline uint32_t policy_get_hint(struct dm_cache_policy *p,
 72				       dm_cblock_t cblock)
 73{
 74	return p->get_hint ? p->get_hint(p, cblock) : 0;
 75}
 76
 77static inline dm_cblock_t policy_residency(struct dm_cache_policy *p)
 78{
 79	return p->residency(p);
 80}
 81
 82static inline void policy_tick(struct dm_cache_policy *p, bool can_block)
 83{
 84	if (p->tick)
 85		return p->tick(p, can_block);
 86}
 87
 88static inline int policy_emit_config_values(struct dm_cache_policy *p, char *result,
 89					    unsigned int maxlen, ssize_t *sz_ptr)
 90{
 91	ssize_t sz = *sz_ptr;
 92
 93	if (p->emit_config_values)
 94		return p->emit_config_values(p, result, maxlen, sz_ptr);
 95
 96	DMEMIT("0 ");
 97	*sz_ptr = sz;
 98	return 0;
 99}
100
101static inline int policy_set_config_value(struct dm_cache_policy *p,
102					  const char *key, const char *value)
103{
104	return p->set_config_value ? p->set_config_value(p, key, value) : -EINVAL;
105}
106
107static inline void policy_allow_migrations(struct dm_cache_policy *p, bool allow)
108{
109	return p->allow_migrations(p, allow);
110}
111
112/*----------------------------------------------------------------*/
113
114/*
115 * Some utility functions commonly used by policies and the core target.
116 */
117static inline size_t bitset_size_in_bytes(unsigned int nr_entries)
118{
119	return sizeof(unsigned long) * dm_div_up(nr_entries, BITS_PER_LONG);
120}
121
122static inline unsigned long *alloc_bitset(unsigned int nr_entries)
123{
124	size_t s = bitset_size_in_bytes(nr_entries);
125
126	return vzalloc(s);
127}
128
129static inline void clear_bitset(void *bitset, unsigned int nr_entries)
130{
131	size_t s = bitset_size_in_bytes(nr_entries);
132
133	memset(bitset, 0, s);
134}
135
136static inline void free_bitset(unsigned long *bits)
137{
138	vfree(bits);
139}
140
141/*----------------------------------------------------------------*/
142
143/*
144 * Creates a new cache policy given a policy name, a cache size, an origin size and the block size.
145 */
146struct dm_cache_policy *dm_cache_policy_create(const char *name, dm_cblock_t cache_size,
147					       sector_t origin_size, sector_t block_size);
148
149/*
150 * Destroys the policy.  This drops references to the policy module as well
151 * as calling it's destroy method.  So always use this rather than calling
152 * the policy->destroy method directly.
153 */
154void dm_cache_policy_destroy(struct dm_cache_policy *p);
155
156/*
157 * In case we've forgotten.
158 */
159const char *dm_cache_policy_get_name(struct dm_cache_policy *p);
160
161const unsigned int *dm_cache_policy_get_version(struct dm_cache_policy *p);
162
163size_t dm_cache_policy_get_hint_size(struct dm_cache_policy *p);
164
165/*----------------------------------------------------------------*/
166
167#endif /* DM_CACHE_POLICY_INTERNAL_H */