OpenCloudOS-Kernel/fs/btrfs/hash.h

44 lines
1.2 KiB
C

/*
* Copyright (C) 2007 Oracle. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#ifndef __HASH__
#define __HASH__
int __init btrfs_hash_init(void);
void btrfs_hash_exit(void);
const char* btrfs_crc32c_impl(void);
u32 btrfs_crc32c(u32 crc, const void *address, unsigned int length);
static inline u64 btrfs_name_hash(const char *name, int len)
{
return btrfs_crc32c((u32)~1, name, len);
}
/*
* Figure the key offset of an extended inode ref
*/
static inline u64 btrfs_extref_hash(u64 parent_objectid, const char *name,
int len)
{
return (u64) btrfs_crc32c(parent_objectid, name, len);
}
#endif