LXR linux/drivers/md/dm-cache-policy-internal.h

   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        return p->remove_mapping(p, oblock);
  65}
  66
  67static inline void policy_force_mapping(struct dm_cache_policy *p,
  68                                        dm_oblock_t current_oblock, dm_oblock_t new_oblock)
  69{
  70        return p->force_mapping(p, current_oblock, new_oblock);
  71}
  72
  73static inline dm_cblock_t policy_residency(struct dm_cache_policy *p)
  74{
  75        return p->residency(p);
  76}
  77
  78static inline void policy_tick(struct dm_cache_policy *p)
  79{
  80        if (p->tick)
  81                return p->tick(p);
  82}
  83
  84static inline int policy_emit_config_values(struct dm_cache_policy *p, char *result, unsigned maxlen)
  85{
  86        ssize_t sz = 0;
  87        if (p->emit_config_values)
  88                return p->emit_config_values(p, result, maxlen);
  89
  90        DMEMIT("0");
  91        return 0;
  92}
  93
  94static inline int policy_set_config_value(struct dm_cache_policy *p,
  95                                          const char *key, const char *value)
  96{
  97        return p->set_config_value ? p->set_config_value(p, key, value) : -EINVAL;
  98}
  99
 100/*----------------------------------------------------------------*/
 101
 102/*
 103 * Creates a new cache policy given a policy name, a cache size, an origin size and the block size.
 104 */
 105struct dm_cache_policy *dm_cache_policy_create(const char *name, dm_cblock_t cache_size,
 106                                               sector_t origin_size, sector_t block_size);
 107
 108/*
 109 * Destroys the policy.  This drops references to the policy module as well
 110 * as calling it's destroy method.  So always use this rather than calling
 111 * the policy->destroy method directly.
 112 */
 113void dm_cache_policy_destroy(struct dm_cache_policy *p);
 114
 115/*
 116 * In case we've forgotten.
 117 */
 118const char *dm_cache_policy_get_name(struct dm_cache_policy *p);
 119
 120const unsigned *dm_cache_policy_get_version(struct dm_cache_policy *p);
 121
 122size_t dm_cache_policy_get_hint_size(struct dm_cache_policy *p);
 123
 124/*----------------------------------------------------------------*/
 125
 126#endif /* DM_CACHE_POLICY_INTERNAL_H */
 127