| Steve Kondik | 2111ad7 | 2013-07-07 12:07:44 -0700 | [diff] [blame] | 1 | /* |
| 2 | * cache.h : deal with indexed LRU caches |
| 3 | * |
| 4 | * Copyright (c) 2008-2010 Jean-Pierre Andre |
| 5 | * |
| 6 | * This program/include file is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU General Public License as published |
| 8 | * by the Free Software Foundation; either version 2 of the License, or |
| 9 | * (at your option) any later version. |
| 10 | * |
| 11 | * This program/include file is distributed in the hope that it will be |
| 12 | * useful, but WITHOUT ANY WARRANTY; without even the implied warranty |
| 13 | * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | * GNU General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU General Public License |
| 17 | * along with this program (in the main directory of the NTFS-3G |
| 18 | * distribution in the file COPYING); if not, write to the Free Software |
| 19 | * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 20 | */ |
| 21 | |
| 22 | #ifndef _NTFS_CACHE_H_ |
| 23 | #define _NTFS_CACHE_H_ |
| 24 | |
| 25 | #include "volume.h" |
| 26 | |
| 27 | struct CACHED_GENERIC { |
| 28 | struct CACHED_GENERIC *next; |
| 29 | struct CACHED_GENERIC *previous; |
| 30 | void *variable; |
| 31 | size_t varsize; |
| 32 | union ALIGNMENT payload[0]; |
| 33 | } ; |
| 34 | |
| 35 | struct CACHED_INODE { |
| 36 | struct CACHED_INODE *next; |
| 37 | struct CACHED_INODE *previous; |
| 38 | const char *pathname; |
| 39 | size_t varsize; |
| 40 | union ALIGNMENT payload[0]; |
| 41 | /* above fields must match "struct CACHED_GENERIC" */ |
| 42 | u64 inum; |
| 43 | } ; |
| 44 | |
| 45 | struct CACHED_NIDATA { |
| 46 | struct CACHED_NIDATA *next; |
| 47 | struct CACHED_NIDATA *previous; |
| 48 | const char *pathname; /* not used */ |
| 49 | size_t varsize; /* not used */ |
| 50 | union ALIGNMENT payload[0]; |
| 51 | /* above fields must match "struct CACHED_GENERIC" */ |
| 52 | u64 inum; |
| 53 | ntfs_inode *ni; |
| 54 | } ; |
| 55 | |
| 56 | struct CACHED_LOOKUP { |
| 57 | struct CACHED_LOOKUP *next; |
| 58 | struct CACHED_LOOKUP *previous; |
| 59 | const char *name; |
| 60 | size_t namesize; |
| 61 | union ALIGNMENT payload[0]; |
| 62 | /* above fields must match "struct CACHED_GENERIC" */ |
| 63 | u64 parent; |
| 64 | u64 inum; |
| 65 | } ; |
| 66 | |
| 67 | enum { |
| 68 | CACHE_FREE = 1, |
| 69 | CACHE_NOHASH = 2 |
| 70 | } ; |
| 71 | |
| 72 | typedef int (*cache_compare)(const struct CACHED_GENERIC *cached, |
| 73 | const struct CACHED_GENERIC *item); |
| 74 | typedef void (*cache_free)(const struct CACHED_GENERIC *cached); |
| 75 | typedef int (*cache_hash)(const struct CACHED_GENERIC *cached); |
| 76 | |
| 77 | struct HASH_ENTRY { |
| 78 | struct HASH_ENTRY *next; |
| 79 | struct CACHED_GENERIC *entry; |
| 80 | } ; |
| 81 | |
| 82 | struct CACHE_HEADER { |
| 83 | const char *name; |
| 84 | struct CACHED_GENERIC *most_recent_entry; |
| 85 | struct CACHED_GENERIC *oldest_entry; |
| 86 | struct CACHED_GENERIC *free_entry; |
| 87 | struct HASH_ENTRY *free_hash; |
| 88 | struct HASH_ENTRY **first_hash; |
| 89 | cache_free dofree; |
| 90 | cache_hash dohash; |
| 91 | unsigned long reads; |
| 92 | unsigned long writes; |
| 93 | unsigned long hits; |
| 94 | int fixed_size; |
| 95 | int max_hash; |
| 96 | struct CACHED_GENERIC entry[0]; |
| 97 | } ; |
| 98 | |
| 99 | /* cast to generic, avoiding gcc warnings */ |
| 100 | #define GENERIC(pstr) ((const struct CACHED_GENERIC*)(const void*)(pstr)) |
| 101 | |
| 102 | struct CACHED_GENERIC *ntfs_fetch_cache(struct CACHE_HEADER *cache, |
| 103 | const struct CACHED_GENERIC *wanted, |
| 104 | cache_compare compare); |
| 105 | struct CACHED_GENERIC *ntfs_enter_cache(struct CACHE_HEADER *cache, |
| 106 | const struct CACHED_GENERIC *item, |
| 107 | cache_compare compare); |
| 108 | int ntfs_invalidate_cache(struct CACHE_HEADER *cache, |
| 109 | const struct CACHED_GENERIC *item, |
| 110 | cache_compare compare, int flags); |
| 111 | int ntfs_remove_cache(struct CACHE_HEADER *cache, |
| 112 | struct CACHED_GENERIC *item, int flags); |
| 113 | |
| 114 | void ntfs_create_lru_caches(ntfs_volume *vol); |
| 115 | void ntfs_free_lru_caches(ntfs_volume *vol); |
| 116 | |
| 117 | #endif /* _NTFS_CACHE_H_ */ |
| 118 | |