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mirror of https://github.com/systemd/systemd-stable.git synced 2024-12-24 21:34:08 +03:00
systemd-stable/extras/volume_id/lib/lvm.c

98 lines
2.0 KiB
C

/*
* 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 lvm1_super_block {
uint8_t id[2];
} PACKED;
struct lvm2_super_block {
uint8_t id[8];
uint64_t sector_xl;
uint32_t crc_xl;
uint32_t offset_xl;
uint8_t type[8];
} PACKED;
#define LVM1_SB_OFF 0x400
#define LVM1_MAGIC "HM"
int volume_id_probe_lvm1(struct volume_id *id, uint64_t off, uint64_t size)
{
const uint8_t *buf;
struct lvm1_super_block *lvm;
info("probing at offset 0x%llx", (unsigned long long) off);
buf = volume_id_get_buffer(id, off + LVM1_SB_OFF, 0x800);
if (buf == NULL)
return -1;
lvm = (struct lvm1_super_block *) buf;
if (memcmp(lvm->id, LVM1_MAGIC, 2) != 0)
return -1;
volume_id_set_usage(id, VOLUME_ID_RAID);
id->type = "LVM1_member";
return 0;
}
#define LVM2_LABEL_ID "LABELONE"
#define LVM2LABEL_SCAN_SECTORS 4
int volume_id_probe_lvm2(struct volume_id *id, uint64_t off, uint64_t size)
{
const uint8_t *buf;
unsigned int soff;
struct lvm2_super_block *lvm;
dbg("probing at offset 0x%llx", (unsigned long long) off);
buf = volume_id_get_buffer(id, off, LVM2LABEL_SCAN_SECTORS * 0x200);
if (buf == NULL)
return -1;
for (soff = 0; soff < LVM2LABEL_SCAN_SECTORS * 0x200; soff += 0x200) {
lvm = (struct lvm2_super_block *) &buf[soff];
if (memcmp(lvm->id, LVM2_LABEL_ID, 8) == 0)
goto found;
}
return -1;
found:
memcpy(id->type_version, lvm->type, 8);
volume_id_set_usage(id, VOLUME_ID_RAID);
id->type = "LVM2_member";
return 0;
}