| 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) Andre Masella <andre@masella.no-ip.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 | /* All these values are taken from ocfs2-tools's ocfs2_fs.h */ |
| 24 | #define OCFS2_VOL_UUID_LEN 16 |
| 25 | #define OCFS2_MAX_VOL_LABEL_LEN 64 |
| 26 | #define OCFS2_SUPERBLOCK_OFFSET 0x2000 |
| 27 | |
| 28 | |
| 29 | /* This is the superblock. The OCFS2 header files have structs in structs. |
| 30 | This is one has been simplified since we only care about the superblock. |
| 31 | */ |
| 32 | |
| 33 | struct ocfs2_super_block { |
| 34 | uint8_t i_signature[8]; /* Signature for validation */ |
| 35 | uint32_t i_generation; /* Generation number */ |
| 36 | int16_t i_suballoc_slot; /* Slot suballocator this inode belongs to */ |
| 37 | uint16_t i_suballoc_bit; /* Bit offset in suballocator block group */ |
| 38 | uint32_t i_reserved0; |
| 39 | uint32_t i_clusters; /* Cluster count */ |
| 40 | uint32_t i_uid; /* Owner UID */ |
| 41 | uint32_t i_gid; /* Owning GID */ |
| 42 | uint64_t i_size; /* Size in bytes */ |
| 43 | uint16_t i_mode; /* File mode */ |
| 44 | uint16_t i_links_count; /* Links count */ |
| 45 | uint32_t i_flags; /* File flags */ |
| 46 | uint64_t i_atime; /* Access time */ |
| 47 | uint64_t i_ctime; /* Creation time */ |
| 48 | uint64_t i_mtime; /* Modification time */ |
| 49 | uint64_t i_dtime; /* Deletion time */ |
| 50 | uint64_t i_blkno; /* Offset on disk, in blocks */ |
| 51 | uint64_t i_last_eb_blk; /* Pointer to last extent block */ |
| 52 | uint32_t i_fs_generation; /* Generation per fs-instance */ |
| 53 | uint32_t i_atime_nsec; |
| 54 | uint32_t i_ctime_nsec; |
| 55 | uint32_t i_mtime_nsec; |
| 56 | uint64_t i_reserved1[9]; |
| 57 | uint64_t i_pad1; /* Generic way to refer to this 64bit union */ |
| 58 | /* Normally there is a union of the different block types, but we only care about the superblock. */ |
| 59 | uint16_t s_major_rev_level; |
| 60 | uint16_t s_minor_rev_level; |
| 61 | uint16_t s_mnt_count; |
| 62 | int16_t s_max_mnt_count; |
| 63 | uint16_t s_state; /* File system state */ |
| 64 | uint16_t s_errors; /* Behaviour when detecting errors */ |
| 65 | uint32_t s_checkinterval; /* Max time between checks */ |
| 66 | uint64_t s_lastcheck; /* Time of last check */ |
| 67 | uint32_t s_creator_os; /* OS */ |
| 68 | uint32_t s_feature_compat; /* Compatible feature set */ |
| 69 | uint32_t s_feature_incompat; /* Incompatible feature set */ |
| 70 | uint32_t s_feature_ro_compat; /* Readonly-compatible feature set */ |
| 71 | uint64_t s_root_blkno; /* Offset, in blocks, of root directory dinode */ |
| 72 | uint64_t s_system_dir_blkno; /* Offset, in blocks, of system directory dinode */ |
| 73 | uint32_t s_blocksize_bits; /* Blocksize for this fs */ |
| 74 | uint32_t s_clustersize_bits; /* Clustersize for this fs */ |
| 75 | uint16_t s_max_slots; /* Max number of simultaneous mounts before tunefs required */ |
| 76 | uint16_t s_reserved1; |
| 77 | uint32_t s_reserved2; |
| 78 | uint64_t s_first_cluster_group; /* Block offset of 1st cluster group header */ |
| 79 | uint8_t s_label[OCFS2_MAX_VOL_LABEL_LEN]; /* Label for mounting, etc. */ |
| 80 | uint8_t s_uuid[OCFS2_VOL_UUID_LEN]; /* 128-bit uuid */ |
| 81 | } __attribute__((__packed__)); |
| 82 | |
| 83 | int volume_id_probe_ocfs2(struct volume_id *id, uint64_t off) |
| 84 | { |
| 85 | struct ocfs2_super_block *os; |
| 86 | |
| 87 | dbg("probing at offset 0x%llx", (unsigned long long) off); |
| 88 | |
| 89 | os = volume_id_get_buffer(id, off + OCFS2_SUPERBLOCK_OFFSET, 0x200); |
| 90 | if (os == NULL) |
| 91 | return -1; |
| 92 | |
| 93 | if (memcmp(os->i_signature, "OCFSV2", 6) != 0) { |
| 94 | return -1; |
| 95 | } |
| 96 | |
| 97 | volume_id_set_usage(id, VOLUME_ID_FILESYSTEM); |
| 98 | volume_id_set_label_raw(id, os->s_label, OCFS2_MAX_VOL_LABEL_LEN < VOLUME_ID_LABEL_SIZE ? |
| 99 | OCFS2_MAX_VOL_LABEL_LEN : VOLUME_ID_LABEL_SIZE); |
| 100 | volume_id_set_label_string(id, os->s_label, OCFS2_MAX_VOL_LABEL_LEN < VOLUME_ID_LABEL_SIZE ? |
| 101 | OCFS2_MAX_VOL_LABEL_LEN : VOLUME_ID_LABEL_SIZE); |
| 102 | volume_id_set_uuid(id, os->s_uuid, UUID_DCE); |
| 103 | id->type = "ocfs2"; |
| 104 | return 0; |
| 105 | } |