1 #ifndef _LINUX_MBCACHE_H 2 #define _LINUX_MBCACHE_H 3 4 #include <linux/hash.h> 5 #include <linux/list_bl.h> 6 #include <linux/list.h> 7 #include <linux/atomic.h> 8 #include <linux/fs.h> 9 10 struct mb_cache; 11 12 struct mb_cache_entry { 13 /* List of entries in cache - protected by cache->c_list_lock */ 14 struct list_head e_list; 15 /* Hash table list - protected by bitlock in e_hash_list_head */ 16 struct hlist_bl_node e_hash_list; 17 atomic_t e_refcnt; 18 /* Key in hash - stable during lifetime of the entry */ 19 u32 e_key; 20 /* Block number of hashed block - stable during lifetime of the entry */ 21 sector_t e_block; 22 /* 23 * Head of hash list (for list bit lock) - stable. Combined with 24 * referenced bit of entry 25 */ 26 unsigned long _e_hash_list_head; 27 }; 28 29 struct mb_cache *mb_cache_create(int bucket_bits); 30 void mb_cache_destroy(struct mb_cache *cache); 31 32 int mb_cache_entry_create(struct mb_cache *cache, gfp_t mask, u32 key, 33 sector_t block); 34 void __mb_cache_entry_free(struct mb_cache_entry *entry); 35 static inline int mb_cache_entry_put(struct mb_cache *cache, 36 struct mb_cache_entry *entry) 37 { 38 if (!atomic_dec_and_test(&entry->e_refcnt)) 39 return 0; 40 __mb_cache_entry_free(entry); 41 return 1; 42 } 43 44 void mb_cache_entry_delete_block(struct mb_cache *cache, u32 key, 45 sector_t block); 46 struct mb_cache_entry *mb_cache_entry_find_first(struct mb_cache *cache, 47 u32 key); 48 struct mb_cache_entry *mb_cache_entry_find_next(struct mb_cache *cache, 49 struct mb_cache_entry *entry); 50 void mb_cache_entry_touch(struct mb_cache *cache, 51 struct mb_cache_entry *entry); 52 53 #endif /* _LINUX_MBCACHE_H */ 54