| Denis Vlasenko | de7684a | 2008-02-18 21:08:49 +0000 | [diff] [blame^] | 1 | /* |
| 2 | * volume_id - reads filesystem label and uuid |
| 3 | * |
| 4 | * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org> |
| 5 | * |
| 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. |
| 10 | * |
| 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. |
| 15 | * |
| 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 |
| 19 | */ |
| 20 | |
| 21 | #include "volume_id_internal.h" |
| 22 | |
| 23 | struct ext2_super_block { |
| 24 | uint32_t inodes_count; |
| 25 | uint32_t blocks_count; |
| 26 | uint32_t r_blocks_count; |
| 27 | uint32_t free_blocks_count; |
| 28 | uint32_t free_inodes_count; |
| 29 | uint32_t first_data_block; |
| 30 | uint32_t log_block_size; |
| 31 | uint32_t dummy3[7]; |
| 32 | uint8_t magic[2]; |
| 33 | uint16_t state; |
| 34 | uint32_t dummy5[8]; |
| 35 | uint32_t feature_compat; |
| 36 | uint32_t feature_incompat; |
| 37 | uint32_t feature_ro_compat; |
| 38 | uint8_t uuid[16]; |
| 39 | uint8_t volume_name[16]; |
| 40 | } __attribute__((__packed__)); |
| 41 | |
| 42 | #define EXT3_FEATURE_COMPAT_HAS_JOURNAL 0x00000004 |
| 43 | #define EXT3_FEATURE_INCOMPAT_JOURNAL_DEV 0x00000008 |
| 44 | #define EXT_SUPERBLOCK_OFFSET 0x400 |
| 45 | |
| 46 | int volume_id_probe_ext(struct volume_id *id, uint64_t off) |
| 47 | { |
| 48 | struct ext2_super_block *es; |
| 49 | |
| 50 | dbg("probing at offset 0x%llx", (unsigned long long) off); |
| 51 | |
| 52 | es = volume_id_get_buffer(id, off + EXT_SUPERBLOCK_OFFSET, 0x200); |
| 53 | if (es == NULL) |
| 54 | return -1; |
| 55 | |
| 56 | if (es->magic[0] != 0123 || |
| 57 | es->magic[1] != 0357) |
| 58 | return -1; |
| 59 | |
| 60 | volume_id_set_usage(id, VOLUME_ID_FILESYSTEM); |
| 61 | volume_id_set_label_raw(id, es->volume_name, 16); |
| 62 | volume_id_set_label_string(id, es->volume_name, 16); |
| 63 | volume_id_set_uuid(id, es->uuid, UUID_DCE); |
| 64 | |
| 65 | if ((le32_to_cpu(es->feature_compat) & EXT3_FEATURE_COMPAT_HAS_JOURNAL) != 0) |
| 66 | id->type = "ext3"; |
| 67 | else |
| 68 | id->type = "ext2"; |
| 69 | |
| 70 | return 0; |
| 71 | } |