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 hash chain bitlock */ 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 u32 e_referenced:1; 21 /* Block number of hashed block - stable during lifetime of the entry */ 22 sector_t e_block; 23 }; 24 25 struct mb_cache *mb_cache_create(int bucket_bits); 26 void mb_cache_destroy(struct mb_cache *cache); 27 28 int mb_cache_entry_create(struct mb_cache *cache, gfp_t mask, u32 key, 29 sector_t block); 30 void __mb_cache_entry_free(struct mb_cache_entry *entry); 31 static inline int mb_cache_entry_put(struct mb_cache *cache, 32 struct mb_cache_entry *entry) 33 { 34 if (!atomic_dec_and_test(&entry->e_refcnt)) 35 return 0; 36 __mb_cache_entry_free(entry); 37 return 1; 38 } 39 40 void mb_cache_entry_delete_block(struct mb_cache *cache, u32 key, 41 sector_t block); 42 struct mb_cache_entry *mb_cache_entry_find_first(struct mb_cache *cache, 43 u32 key); 44 struct mb_cache_entry *mb_cache_entry_find_next(struct mb_cache *cache, 45 struct mb_cache_entry *entry); 46 void mb_cache_entry_touch(struct mb_cache *cache, 47 struct mb_cache_entry *entry); 48 49 #endif /* _LINUX_MBCACHE_H */ 50