btrfs-progs/kernel-lib/raid56.h

63 lines
2.1 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__
#include "kerncompat.h"
#include <stddef.h>
#include "kernel-lib/bitops.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