2 * volume_id - reads filesystem label and uuid
4 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
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.
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.
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
36 #include "volume_id.h"
41 struct ext2_super_block {
42 uint32_t inodes_count;
43 uint32_t blocks_count;
44 uint32_t r_blocks_count;
45 uint32_t free_blocks_count;
46 uint32_t free_inodes_count;
47 uint32_t first_data_block;
48 uint32_t log_block_size;
53 uint32_t feature_compat;
54 uint32_t feature_incompat;
55 uint32_t feature_ro_compat;
57 uint8_t volume_name[16];
58 } __attribute__((__packed__));
60 #define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x00000004
61 #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x00000008
62 #define EXT_SUPERBLOCK_OFFSET 0x400
64 int volume_id_probe_ext(struct volume_id *id, uint64_t off)
66 struct ext2_super_block *es;
68 dbg("probing at offset 0x%llx", (unsigned long long) off);
70 es = (struct ext2_super_block *) volume_id_get_buffer(id, off + EXT_SUPERBLOCK_OFFSET, 0x200);
74 if (es->magic[0] != 0123 ||
78 volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
79 volume_id_set_label_raw(id, es->volume_name, 16);
80 volume_id_set_label_string(id, es->volume_name, 16);
81 volume_id_set_uuid(id, es->uuid, UUID_DCE);
83 if ((le32_to_cpu(es->feature_compat) & EXT3_FEATURE_COMPAT_HAS_JOURNAL) != 0)