include/linux/mbcache.h

   1 /*
   2   File: linux/mbcache.h
   3
   4   (C) 2001 by Andreas Gruenbacher, <a.gruenbacher@computer.org>
   5 */
   6
   7 /* Hardwire the number of additional indexes */
   8 #define MB_CACHE_INDEXES_COUNT 1
   9
  10 struct mb_cache_entry;
  11
  12 struct mb_cache_op {
  13         int (*free)(struct mb_cache_entry *, int);
  14 };
  15
  16 struct mb_cache {
  17         struct list_head                c_cache_list;
  18         const char                      *c_name;
  19         struct mb_cache_op              c_op;
  20         atomic_t                        c_entry_count;
  21         int                             c_bucket_bits;
  22 #ifndef MB_CACHE_INDEXES_COUNT
  23         int                             c_indexes_count;
  24 #endif
  25         kmem_cache_t                    *c_entry_cache;
  26         struct list_head                *c_block_hash;
  27         struct list_head                *c_indexes_hash[0];
  28 };
  29
  30 struct mb_cache_entry_index {
  31         struct list_head                o_list;
  32         unsigned int                    o_key;
  33 };
  34
  35 struct mb_cache_entry {
  36         struct list_head                e_lru_list;
  37         struct mb_cache                 *e_cache;
  38         atomic_t                        e_used;
  39         struct block_device             *e_bdev;
  40         sector_t                        e_block;
  41         struct list_head                e_block_list;
  42         struct mb_cache_entry_index     e_indexes[0];
  43 };
  44
  45 /* Functions on caches */
  46
  47 struct mb_cache * mb_cache_create(const char *, struct mb_cache_op *, size_t,
  48                                   int, int);
  49 void mb_cache_shrink(struct mb_cache *, struct block_device *);
  50 void mb_cache_destroy(struct mb_cache *);
  51
  52 /* Functions on cache entries */
  53
  54 struct mb_cache_entry *mb_cache_entry_alloc(struct mb_cache *);
  55 int mb_cache_entry_insert(struct mb_cache_entry *, struct block_device *,
  56                           sector_t, unsigned int[]);
  57 void mb_cache_entry_rehash(struct mb_cache_entry *, unsigned int[]);
  58 void mb_cache_entry_release(struct mb_cache_entry *);
  59 void mb_cache_entry_takeout(struct mb_cache_entry *);
  60 void mb_cache_entry_free(struct mb_cache_entry *);
  61 struct mb_cache_entry *mb_cache_entry_dup(struct mb_cache_entry *);
  62 struct mb_cache_entry *mb_cache_entry_get(struct mb_cache *,
  63                                           struct block_device *,
  64                                           sector_t);
  65 #if !defined(MB_CACHE_INDEXES_COUNT) || (MB_CACHE_INDEXES_COUNT > 0)
  66 struct mb_cache_entry *mb_cache_entry_find_first(struct mb_cache *cache, int,
  67                                                  struct block_device *,
  68                                                  unsigned int);
  69 struct mb_cache_entry *mb_cache_entry_find_next(struct mb_cache_entry *, int,
  70                                                 struct block_device *,
  71                                                 unsigned int);
  72 #endif