btrfs-progs/kernel-lib/raid56.h
Qu Wenruo 05734124f2 btrfs-progs: Introduce wrapper to recover raid56 data
Introduce a wrapper to recover raid56 data.

The logical is the same with kernel one, but with different interfaces,
since kernel ones cares the performance while in btrfs we don't care
that much.

And the interface is more caller friendly inside btrfs-progs.

Signed-off-by: Qu Wenruo <quwenruo@cn.fujitsu.com>
Signed-off-by: David Sterba <dsterba@suse.com>
2017-07-03 13:35:11 +02:00

59 lines
2 KiB
C

/*
* 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.
*/
/*
* Original headers from kernel library for RAID5/6 calculations, not from
* btrfs kernel header.
*/
#ifndef __BTRFS_PROGS_RAID56_H__
#define __BTRFS_PROGS_RAID56_H__
void raid6_gen_syndrome(int disks, size_t bytes, void **ptrs);
int raid5_gen_result(int nr_devs, size_t stripe_len, int dest, void **data);
/*
* Headers synchronized from kernel include/linux/raid/pq.h
* No modification at all.
*
* Galois field tables.
*/
extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256)));
extern const u8 raid6_vgfmul[256][32] __attribute__((aligned(256)));
extern const u8 raid6_gfexp[256] __attribute__((aligned(256)));
extern const u8 raid6_gfinv[256] __attribute__((aligned(256)));
extern const u8 raid6_gfexi[256] __attribute__((aligned(256)));
/* Recover raid6 with 2 data stripes corrupted */
int raid6_recov_data2(int nr_devs, size_t stripe_len, int dest1, int dest2,
void **data);
/* Recover data and P */
int raid6_recov_datap(int nr_devs, size_t stripe_len, int dest1, void **data);
/*
* Recover raid56 data
* @dest1/2 can be -1 to indicate correct data
*
* Return >0 for unrecoverable case.
* Return 0 for recoverable case, And recovered data will be stored into @data
* Return <0 for fatal error
*/
int raid56_recov(int nr_devs, size_t stripe_len, u64 profile, int dest1,
int dest2, void **data);
#endif