LXR busybox/util-linux/volume_id/linux

   1/*
   2 * volume_id - reads filesystem label and uuid
   3 *
   4 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
   5 *
   6 *      This library is free software; you can redistribute it and/or
   7 *      modify it under the terms of the GNU Lesser General Public
   8 *      License as published by the Free Software Foundation; either
   9 *      version 2.1 of the License, or (at your option) any later version.
  10 *
  11 *      This library 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 GNU
  14 *      Lesser General Public License for more details.
  15 *
  16 *      You should have received a copy of the GNU Lesser General Public
  17 *      License along with this library; if not, write to the Free Software
  18 *      Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  19 */
  20//config:config FEATURE_VOLUMEID_LINUXRAID
  21//config:       bool "linuxraid"
  22//config:       default y
  23//config:       depends on VOLUMEID
  24
  25//kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_LINUXRAID) += linux_raid.o
  26
  27#include "volume_id_internal.h"
  28
  29struct mdp_super_block {
  30        uint32_t        md_magic;
  31        uint32_t        major_version;
  32        uint32_t        minor_version;
  33        uint32_t        patch_version;
  34        uint32_t        gvalid_words;
  35        uint32_t        set_uuid0;
  36        uint32_t        ctime;
  37        uint32_t        level;
  38        uint32_t        size;
  39        uint32_t        nr_disks;
  40        uint32_t        raid_disks;
  41        uint32_t        md_minor;
  42        uint32_t        not_persistent;
  43        uint32_t        set_uuid1;
  44        uint32_t        set_uuid2;
  45        uint32_t        set_uuid3;
  46} PACKED;
  47
  48#define MD_RESERVED_BYTES               0x10000
  49#define MD_MAGIC                        0xa92b4efc
  50
  51int FAST_FUNC volume_id_probe_linux_raid(struct volume_id *id /*,uint64_t off*/, uint64_t size)
  52{
  53        typedef uint32_t aliased_uint32_t FIX_ALIASING;
  54#define off ((uint64_t)0)
  55        uint64_t sboff;
  56        uint8_t uuid[16];
  57        struct mdp_super_block *mdp;
  58
  59        dbg("probing at offset 0x%llx, size 0x%llx",
  60            (unsigned long long) off, (unsigned long long) size);
  61
  62        if (size < 0x10000)
  63                return -1;
  64
  65        sboff = (size & ~(MD_RESERVED_BYTES - 1)) - MD_RESERVED_BYTES;
  66        mdp = volume_id_get_buffer(id, off + sboff, 0x800);
  67        if (mdp == NULL)
  68                return -1;
  69
  70        if (mdp->md_magic != cpu_to_le32(MD_MAGIC))
  71                return -1;
  72
  73        *(aliased_uint32_t*)uuid = mdp->set_uuid0;
  74        memcpy(&uuid[4], &mdp->set_uuid1, 12);
  75        volume_id_set_uuid(id, uuid, UUID_DCE);
  76
  77//      snprintf(id->type_version, sizeof(id->type_version)-1, "%u.%u.%u",
  78//              le32_to_cpu(mdp->major_version),
  79//              le32_to_cpu(mdp->minor_version),
  80//              le32_to_cpu(mdp->patch_version));
  81
  82        dbg("found raid signature");
  83//      volume_id_set_usage(id, VOLUME_ID_RAID);
  84        IF_FEATURE_BLKID_TYPE(id->type = "linux_raid_member";)
  85
  86        return 0;
  87}
  88