busybox/util-linux/volume_id/lvm.c
Denis Vlasenko de7684a309 support for mount by label (not yet tested)
Also adds findfs applet. Closes bug 1143.
2008-02-18 21:08:49 +00:00

92 lines
2.3 KiB
C

/*
* volume_id - reads filesystem label and uuid
*
* Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "volume_id_internal.h"
struct lvm1_super_block {
uint8_t id[2];
} __attribute__((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];
} __attribute__((packed));
#define LVM1_SB_OFF 0x400
#define LVM1_MAGIC "HM"
int volume_id_probe_lvm1(struct volume_id *id, uint64_t off)
{
const uint8_t *buf;
struct lvm1_super_block *lvm;
dbg("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)
{
const uint8_t *buf;
unsigned 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;
}