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
22int __init btrfs_hash_init(void);
23
24void btrfs_hash_exit(void);
25
26u32 btrfs_crc32c(u32 crc, const void *address, unsigned int length);
27
28static 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 */
36static 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