1 /*
2   File: linux/mbcache.h
3 
4   (C) 2001 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
5 */
6 struct mb_cache_entry {
7 	struct list_head		e_lru_list;
8 	struct mb_cache			*e_cache;
9 	unsigned short			e_used;
10 	unsigned short			e_queued;
11 	atomic_t			e_refcnt;
12 	struct block_device		*e_bdev;
13 	sector_t			e_block;
14 	struct hlist_bl_node		e_block_list;
15 	struct {
16 		struct hlist_bl_node	o_list;
17 		unsigned int		o_key;
18 	} e_index;
19 	struct hlist_bl_head		*e_block_hash_p;
20 	struct hlist_bl_head		*e_index_hash_p;
21 };
22 
23 struct mb_cache {
24 	struct list_head		c_cache_list;
25 	const char			*c_name;
26 	atomic_t			c_entry_count;
27 	int				c_max_entries;
28 	int				c_bucket_bits;
29 	struct kmem_cache		*c_entry_cache;
30 	struct hlist_bl_head		*c_block_hash;
31 	struct hlist_bl_head		*c_index_hash;
32 };
33 
34 /* Functions on caches */
35 
36 struct mb_cache *mb_cache_create(const char *, int);
37 void mb_cache_shrink(struct block_device *);
38 void mb_cache_destroy(struct mb_cache *);
39 
40 /* Functions on cache entries */
41 
42 struct mb_cache_entry *mb_cache_entry_alloc(struct mb_cache *, gfp_t);
43 int mb_cache_entry_insert(struct mb_cache_entry *, struct block_device *,
44 			  sector_t, unsigned int);
45 void mb_cache_entry_release(struct mb_cache_entry *);
46 void mb_cache_entry_free(struct mb_cache_entry *);
47 struct mb_cache_entry *mb_cache_entry_get(struct mb_cache *,
48 					  struct block_device *,
49 					  sector_t);
50 struct mb_cache_entry *mb_cache_entry_find_first(struct mb_cache *cache,
51 						 struct block_device *,
52 						 unsigned int);
53 struct mb_cache_entry *mb_cache_entry_find_next(struct mb_cache_entry *,
54 						struct block_device *,
55 						unsigned int);
56