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         struct list_head                e_lru_list;
  12         struct mb_cache                 *e_cache;
  13         unsigned short                  e_used;
  14         unsigned short                  e_queued;
  15         struct block_device             *e_bdev;
  16         sector_t                        e_block;
  17         struct list_head                e_block_list;
  18         struct {
  19                 struct list_head        o_list;
  20                 unsigned int            o_key;
  21         } e_indexes[0];
  22 };
  23
  24 struct mb_cache_op {
  25         int (*free)(struct mb_cache_entry *, gfp_t);
  26 };
  27
  28 /* Functions on caches */
  29
  30 struct mb_cache * mb_cache_create(const char *, struct mb_cache_op *, size_t,
  31                                   int, int);
  32 void mb_cache_shrink(struct block_device *);
  33 void mb_cache_destroy(struct mb_cache *);
  34
  35 /* Functions on cache entries */
  36
  37 struct mb_cache_entry *mb_cache_entry_alloc(struct mb_cache *);
  38 int mb_cache_entry_insert(struct mb_cache_entry *, struct block_device *,
  39                           sector_t, unsigned int[]);
  40 void mb_cache_entry_release(struct mb_cache_entry *);
  41 void mb_cache_entry_free(struct mb_cache_entry *);
  42 struct mb_cache_entry *mb_cache_entry_get(struct mb_cache *,
  43                                           struct block_device *,
  44                                           sector_t);
  45 #if !defined(MB_CACHE_INDEXES_COUNT) || (MB_CACHE_INDEXES_COUNT > 0)
  46 struct mb_cache_entry *mb_cache_entry_find_first(struct mb_cache *cache, int,
  47                                                  struct block_device *,
  48                                                  unsigned int);
  49 struct mb_cache_entry *mb_cache_entry_find_next(struct mb_cache_entry *, int,
  50                                                 struct block_device *,
  51                                                 unsigned int);
  52 #endif