1 /*
2 * Copyright (C) 2007 Oracle. All rights reserved.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
7 *
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
12 *
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
17 */
18
19 #ifndef __HASH__
20 #define __HASH__
21
22 int __init btrfs_hash_init(void);
23
24 void btrfs_hash_exit(void);
25
26 u32 btrfs_crc32c(u32 crc, const void *address, unsigned int length);
27
btrfs_name_hash(const char * name,int len)28 static inline u64 btrfs_name_hash(const char *name, int len)
29 {
30 return btrfs_crc32c((u32)~1, name, len);
31 }
32
33 /*
34 * Figure the key offset of an extended inode ref
35 */
btrfs_extref_hash(u64 parent_objectid,const char * name,int len)36 static inline u64 btrfs_extref_hash(u64 parent_objectid, const char *name,
37 int len)
38 {
39 return (u64) btrfs_crc32c(parent_objectid, name, len);
40 }
41
42 #endif
43