1/*
2  File: linux/mbcache.h
3
4  (C) 2001 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
5*/
6struct 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
23struct 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
36struct mb_cache *mb_cache_create(const char *, int);
37void mb_cache_shrink(struct block_device *);
38void mb_cache_destroy(struct mb_cache *);
39
40/* Functions on cache entries */
41
42struct mb_cache_entry *mb_cache_entry_alloc(struct mb_cache *, gfp_t);
43int mb_cache_entry_insert(struct mb_cache_entry *, struct block_device *,
44			  sector_t, unsigned int);
45void mb_cache_entry_release(struct mb_cache_entry *);
46void mb_cache_entry_free(struct mb_cache_entry *);
47struct mb_cache_entry *mb_cache_entry_get(struct mb_cache *,
48					  struct block_device *,
49					  sector_t);
50struct mb_cache_entry *mb_cache_entry_find_first(struct mb_cache *cache,
51						 struct block_device *,
52						 unsigned int);
53struct mb_cache_entry *mb_cache_entry_find_next(struct mb_cache_entry *,
54						struct block_device *,
55						unsigned int);
56