linux_raid.c revision b5e694267142042228a6cac99ecad6c4b4ef8759
/*
* volume_id - reads filesystem label and uuid
*
* Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
*
* This program 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 version 2 of the License.
*/
#ifndef _GNU_SOURCE
#define _GNU_SOURCE 1
#endif
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <ctype.h>
#include "libvolume_id.h"
#include "util.h"
struct mdp_super_block {
uint32_t md_magic;
uint32_t major_version;
uint32_t minor_version;
uint32_t patch_version;
uint32_t gvalid_words;
uint32_t set_uuid0;
uint32_t ctime;
uint32_t level;
uint32_t size;
uint32_t nr_disks;
uint32_t raid_disks;
uint32_t md_minor;
uint32_t not_persistent;
uint32_t set_uuid1;
uint32_t set_uuid2;
uint32_t set_uuid3;
} PACKED *mdp;
#define MD_RESERVED_BYTES 0x10000
#define MD_MAGIC 0xa92b4efc
int volume_id_probe_linux_raid(struct volume_id *id, uint64_t off, uint64_t size)
{
const uint8_t *buf;
uint64_t sboff;
uint8_t uuid[16];
dbg("probing at offset 0x%llx, size 0x%llx",
(unsigned long long) off, (unsigned long long) size);
if (size < 0x10000)
return -1;
sboff = (size & ~(MD_RESERVED_BYTES - 1)) - MD_RESERVED_BYTES;
buf = volume_id_get_buffer(id, off + sboff, 0x800);
if (buf == NULL)
return -1;
mdp = (struct mdp_super_block *) buf;
if (le32_to_cpu(mdp->md_magic) != MD_MAGIC)
return -1;
memcpy(uuid, &mdp->set_uuid0, 4);
memcpy(&uuid[4], &mdp->set_uuid1, 12);
volume_id_set_uuid(id, uuid, UUID_DCE);
snprintf(id->type_version, sizeof(id->type_version)-1, "%u.%u.%u",
le32_to_cpu(mdp->major_version),
le32_to_cpu(mdp->minor_version),
le32_to_cpu(mdp->patch_version));
dbg("found raid signature");
volume_id_set_usage(id, VOLUME_ID_RAID);
id->type = "linux_raid_member";
return 0;
}