linux-stable/include/linux/mbcache.h

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#ifndef _LINUX_MBCACHE_H
#define _LINUX_MBCACHE_H
#include <linux/hash.h>
#include <linux/list_bl.h>
#include <linux/list.h>
#include <linux/atomic.h>
#include <linux/fs.h>
struct mb_cache;
struct mb_cache_entry {
/* List of entries in cache - protected by cache->c_list_lock */
struct list_head e_list;
/* Hash table list - protected by hash chain bitlock */
struct hlist_bl_node e_hash_list;
atomic_t e_refcnt;
/* Key in hash - stable during lifetime of the entry */
u32 e_key;
u32 e_referenced:1;
u32 e_reusable:1;
/* Block number of hashed block - stable during lifetime of the entry */
sector_t e_block;
};
struct mb_cache *mb_cache_create(int bucket_bits);
void mb_cache_destroy(struct mb_cache *cache);
int mb_cache_entry_create(struct mb_cache *cache, gfp_t mask, u32 key,
sector_t block, bool reusable);
void __mb_cache_entry_free(struct mb_cache_entry *entry);
static inline int mb_cache_entry_put(struct mb_cache *cache,
struct mb_cache_entry *entry)
{
if (!atomic_dec_and_test(&entry->e_refcnt))
return 0;
__mb_cache_entry_free(entry);
return 1;
}
void mb_cache_entry_delete_block(struct mb_cache *cache, u32 key,
sector_t block);
struct mb_cache_entry *mb_cache_entry_get(struct mb_cache *cache, u32 key,
sector_t block);
struct mb_cache_entry *mb_cache_entry_find_first(struct mb_cache *cache,
u32 key);
struct mb_cache_entry *mb_cache_entry_find_next(struct mb_cache *cache,
struct mb_cache_entry *entry);
void mb_cache_entry_touch(struct mb_cache *cache,
struct mb_cache_entry *entry);
#endif /* _LINUX_MBCACHE_H */