/* raid5_recover.c - module to recover from faulty RAID4/5 arrays.  */
/*
 *  VAS_EBOOT  --  GRand Unified Bootloader
 *  Copyright (C) 2006,2007,2008  Free Software Foundation, Inc.
 *
 *  VAS_EBOOT is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  VAS_EBOOT 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 VAS_EBOOT.  If not, see <http://www.gnu.org/licenses/>.
 */

#include <VasEBoot/dl.h>
#include <VasEBoot/disk.h>
#include <VasEBoot/mm.h>
#include <VasEBoot/err.h>
#include <VasEBoot/misc.h>
#include <VasEBoot/diskfilter.h>
#include <VasEBoot/crypto.h>

VAS_EBOOT_MOD_LICENSE ("GPLv3+");

static VasEBoot_err_t
VasEBoot_raid5_recover (struct VasEBoot_diskfilter_segment *array, int disknr,
                    char *buf, VasEBoot_disk_addr_t sector, VasEBoot_size_t size)
{
  char *buf2;
  int i;

  size <<= VAS_EBOOT_DISK_SECTOR_BITS;
  buf2 = VasEBoot_malloc (size);
  if (!buf2)
    return VasEBoot_errno;

  VasEBoot_memset (buf, 0, size);

  for (i = 0; i < (int) array->node_count; i++)
    {
      VasEBoot_err_t err;

      if (i == disknr)
        continue;

      err = VasEBoot_diskfilter_read_node (&array->nodes[i], sector,
				       size >> VAS_EBOOT_DISK_SECTOR_BITS, buf2);

      if (err)
        {
          VasEBoot_free (buf2);
          return err;
        }

      VasEBoot_crypto_xor (buf, buf, buf2, size);
    }

  VasEBoot_free (buf2);

  return VAS_EBOOT_ERR_NONE;
}

VAS_EBOOT_MOD_INIT(raid5rec)
{
  VasEBoot_raid5_recover_func = VasEBoot_raid5_recover;
}

VAS_EBOOT_MOD_FINI(raid5rec)
{
  VasEBoot_raid5_recover_func = 0;
}