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 u32 e_reusable:1;
22 /* Block number of hashed block - stable during lifetime of the entry */
23 sector_t e_block;
24 };
25
26 struct mb_cache *mb_cache_create(int bucket_bits);
27 void mb_cache_destroy(struct mb_cache *cache);
28
29 int mb_cache_entry_create(struct mb_cache *cache, gfp_t mask, u32 key,
30 sector_t block, bool reusable);
31 void __mb_cache_entry_free(struct mb_cache_entry *entry);
mb_cache_entry_put(struct mb_cache * cache,struct mb_cache_entry * entry)32 static inline int mb_cache_entry_put(struct mb_cache *cache,
33 struct mb_cache_entry *entry)
34 {
35 if (!atomic_dec_and_test(&entry->e_refcnt))
36 return 0;
37 __mb_cache_entry_free(entry);
38 return 1;
39 }
40
41 void mb_cache_entry_delete_block(struct mb_cache *cache, u32 key,
42 sector_t block);
43 struct mb_cache_entry *mb_cache_entry_get(struct mb_cache *cache, u32 key,
44 sector_t block);
45 struct mb_cache_entry *mb_cache_entry_find_first(struct mb_cache *cache,
46 u32 key);
47 struct mb_cache_entry *mb_cache_entry_find_next(struct mb_cache *cache,
48 struct mb_cache_entry *entry);
49 void mb_cache_entry_touch(struct mb_cache *cache,
50 struct mb_cache_entry *entry);
51
52 #endif /* _LINUX_MBCACHE_H */
53