linux/drivers/md/dm-cache-policy-internal.h
Mike Snitzer 4e7f506f64 dm cache: policy change version from string to integer set
Separate dm cache policy version string into 3 unsigned numbers
corresponding to major, minor and patchlevel and store them at the end
of the on-disk metadata so we know which version of the policy generated
the hints in case a future version wants to use them differently.

Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
2013-03-20 17:21:27 +00:00

127 lines
3.5 KiB
C

/*
* Copyright (C) 2012 Red Hat. All rights reserved.
*
* This file is released under the GPL.
*/
#ifndef DM_CACHE_POLICY_INTERNAL_H
#define DM_CACHE_POLICY_INTERNAL_H
#include "dm-cache-policy.h"
/*----------------------------------------------------------------*/
/*
* Little inline functions that simplify calling the policy methods.
*/
static inline int 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_result *result)
{
return p->map(p, oblock, can_block, can_migrate, discarded_oblock, bio, result);
}
static inline int policy_lookup(struct dm_cache_policy *p, dm_oblock_t oblock, dm_cblock_t *cblock)
{
BUG_ON(!p->lookup);
return p->lookup(p, oblock, cblock);
}
static inline void policy_set_dirty(struct dm_cache_policy *p, dm_oblock_t oblock)
{
if (p->set_dirty)
p->set_dirty(p, oblock);
}
static inline void policy_clear_dirty(struct dm_cache_policy *p, dm_oblock_t oblock)
{
if (p->clear_dirty)
p->clear_dirty(p, oblock);
}
static inline int policy_load_mapping(struct dm_cache_policy *p,
dm_oblock_t oblock, dm_cblock_t cblock,
uint32_t hint, bool hint_valid)
{
return p->load_mapping(p, oblock, cblock, hint, hint_valid);
}
static inline int policy_walk_mappings(struct dm_cache_policy *p,
policy_walk_fn fn, void *context)
{
return p->walk_mappings ? p->walk_mappings(p, fn, context) : 0;
}
static inline int policy_writeback_work(struct dm_cache_policy *p,
dm_oblock_t *oblock,
dm_cblock_t *cblock)
{
return p->writeback_work ? p->writeback_work(p, oblock, cblock) : -ENOENT;
}
static inline void policy_remove_mapping(struct dm_cache_policy *p, dm_oblock_t oblock)
{
return p->remove_mapping(p, oblock);
}
static inline void policy_force_mapping(struct dm_cache_policy *p,
dm_oblock_t current_oblock, dm_oblock_t new_oblock)
{
return p->force_mapping(p, current_oblock, new_oblock);
}
static inline dm_cblock_t policy_residency(struct dm_cache_policy *p)
{
return p->residency(p);
}
static inline void policy_tick(struct dm_cache_policy *p)
{
if (p->tick)
return p->tick(p);
}
static inline int policy_emit_config_values(struct dm_cache_policy *p, char *result, unsigned maxlen)
{
ssize_t sz = 0;
if (p->emit_config_values)
return p->emit_config_values(p, result, maxlen);
DMEMIT("0");
return 0;
}
static inline int policy_set_config_value(struct dm_cache_policy *p,
const char *key, const char *value)
{
return p->set_config_value ? p->set_config_value(p, key, value) : -EINVAL;
}
/*----------------------------------------------------------------*/
/*
* Creates a new cache policy given a policy name, a cache size, an origin size and the block size.
*/
struct dm_cache_policy *dm_cache_policy_create(const char *name, dm_cblock_t cache_size,
sector_t origin_size, sector_t block_size);
/*
* Destroys the policy. This drops references to the policy module as well
* as calling it's destroy method. So always use this rather than calling
* the policy->destroy method directly.
*/
void dm_cache_policy_destroy(struct dm_cache_policy *p);
/*
* In case we've forgotten.
*/
const char *dm_cache_policy_get_name(struct dm_cache_policy *p);
const unsigned *dm_cache_policy_get_version(struct dm_cache_policy *p);
size_t dm_cache_policy_get_hint_size(struct dm_cache_policy *p);
/*----------------------------------------------------------------*/
#endif /* DM_CACHE_POLICY_INTERNAL_H */