linux_raid.c revision 2603474ff9be2418900581da1af5cccc9f13cae1
/*
* 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 <byteswap.h>
#include "libvolume_id.h"
#include "libvolume_id-private.h"
#include "util.h"
struct mdp0_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;
struct mdp1_super_block {
uint32_t magic;
uint32_t major_version;
uint32_t feature_map;
uint32_t pad0;
uint8_t set_uuid[16];
uint8_t set_name[32];
} PACKED;
#define MD_RESERVED_BYTES 0x10000
#define MD_SB_MAGIC 0xa92b4efc
static int volume_id_probe_linux_raid0(struct volume_id *id, uint64_t off, uint64_t size)
{
const uint8_t *buf;
struct mdp0_super_block *mdp0;
union {
uint32_t ints[4];
uint8_t bytes[16];
} uuid;
info("probing at offset 0x%llx, size 0x%llx\n",
(unsigned long long) off, (unsigned long long) size);
if (size < 0x10000)
return -1;
buf = volume_id_get_buffer(id, off, 0x800);
if (buf == NULL)
return -1;
mdp0 = (struct mdp0_super_block *) buf;
if (le32_to_cpu(mdp0->md_magic) == MD_SB_MAGIC) {
uuid.ints[0] = bswap_32(mdp0->set_uuid0);
if (le32_to_cpu(mdp0->minor_version >= 90)) {
uuid.ints[1] = bswap_32(mdp0->set_uuid1);
uuid.ints[2] = bswap_32(mdp0->set_uuid2);
uuid.ints[3] = bswap_32(mdp0->set_uuid3);
} else {
uuid.ints[1] = 0;
uuid.ints[2] = 0;
uuid.ints[3] = 0;
}
volume_id_set_uuid(id, uuid.bytes, 0, UUID_MD);
snprintf(id->type_version, sizeof(id->type_version)-1, "%u.%u.%u",
le32_to_cpu(mdp0->major_version),
le32_to_cpu(mdp0->minor_version),
le32_to_cpu(mdp0->patch_version));
} else if (be32_to_cpu(mdp0->md_magic) == MD_SB_MAGIC) {
uuid.ints[0] = mdp0->set_uuid0;
if (be32_to_cpu(mdp0->minor_version >= 90)) {
uuid.ints[1] = mdp0->set_uuid1;
uuid.ints[2] = mdp0->set_uuid2;
uuid.ints[3] = mdp0->set_uuid3;
} else {
uuid.ints[1] = 0;
uuid.ints[2] = 0;
uuid.ints[3] = 0;
}
volume_id_set_uuid(id, uuid.bytes, 0, UUID_MD);
snprintf(id->type_version, sizeof(id->type_version)-1, "%u.%u.%u",
be32_to_cpu(mdp0->major_version),
be32_to_cpu(mdp0->minor_version),
be32_to_cpu(mdp0->patch_version));
} else
return -1;
volume_id_set_usage(id, VOLUME_ID_RAID);
id->type = "linux_raid_member";
return 0;
}
static int volume_id_probe_linux_raid1(struct volume_id *id, uint64_t off, uint64_t size)
{
const uint8_t *buf;
struct mdp1_super_block *mdp1;
info("probing at offset 0x%llx, size 0x%llx\n",
(unsigned long long) off, (unsigned long long) size);
buf = volume_id_get_buffer(id, off, 0x800);
if (buf == NULL)
return -1;
mdp1 = (struct mdp1_super_block *) buf;
if (le32_to_cpu(mdp1->magic) != MD_SB_MAGIC)
return -1;
if (le32_to_cpu(mdp1->major_version) != 1)
return -1;
volume_id_set_uuid(id, mdp1->set_uuid, 0, UUID_MD);
volume_id_set_label_raw(id, mdp1->set_name, 32);
volume_id_set_label_string(id, mdp1->set_name, 32);
volume_id_set_usage(id, VOLUME_ID_RAID);
id->type = "linux_raid_member";
return 0;
}
int volume_id_probe_linux_raid(struct volume_id *id, uint64_t off, uint64_t size)
{
uint64_t sboff;
/* version 0 at the end of the device */
sboff = (size & ~(MD_RESERVED_BYTES - 1)) - MD_RESERVED_BYTES;
if (volume_id_probe_linux_raid0(id, off + sboff, size) == 0)
return 0;
/* version 1.0 at the end of the device */
sboff = (size & ~(0x1000 - 1)) - 0x2000;
if (volume_id_probe_linux_raid1(id, off + sboff, size) == 0)
strcpy(id->type_version, "1.0");
/* version 1.1 at the start of the device */
else if (volume_id_probe_linux_raid1(id, off, size) == 0)
strcpy(id->type_version, "1.1");
/* version 1.2 at 4k offset from the start */
else if (volume_id_probe_linux_raid1(id, off + 0x1000, size) == 0)
strcpy(id->type_version, "1.2");
else
return -1;
return 0;
}