extras/volume_id/lib/jmicron_raid.c

   1 /*
   2  * volume_id - reads filesystem label and uuid
   3  *
   4  * Copyright (C) 2006 Kay Sievers <kay.sievers@vrfy.org>
   5  *
   6  * This program is free software: you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation, either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  18  */
  19
  20 #ifndef _GNU_SOURCE
  21 #define _GNU_SOURCE 1
  22 #endif
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <unistd.h>
  27 #include <string.h>
  28 #include <errno.h>
  29 #include <ctype.h>
  30
  31 #include "libvolume_id.h"
  32 #include "libvolume_id-private.h"
  33
  34 struct jmicron_meta {
  35         int8_t          signature[2];
  36         uint8_t         minor_version;
  37         uint8_t         major_version;
  38         uint16_t        checksum;
  39 } PACKED;
  40
  41 int volume_id_probe_jmicron_raid(struct volume_id *id, uint64_t off, uint64_t size)
  42 {
  43         const uint8_t *buf;
  44         uint64_t meta_off;
  45         struct jmicron_meta *jm;
  46
  47         info("probing at offset 0x%llx, size 0x%llx\n",
  48             (unsigned long long) off, (unsigned long long) size);
  49
  50         if (size < 0x10000)
  51                 return -1;
  52
  53         meta_off = ((size / 0x200)-1) * 0x200;
  54         buf = volume_id_get_buffer(id, off + meta_off, 0x200);
  55         if (buf == NULL)
  56                 return -1;
  57
  58         jm = (struct jmicron_meta *) buf;
  59         if (memcmp(jm->signature, "JM", 2) != 0)
  60                 return -1;
  61
  62         volume_id_set_usage(id, VOLUME_ID_RAID);
  63         snprintf(id->type_version, sizeof(id->type_version)-1, "%u.%u", jm->major_version, jm->minor_version);
  64         id->type = "jmicron_raid_member";
  65
  66         return 0;
  67 }