2 * volume_id - reads filesystem label and uuid
4 * Copyright (C) Andre Masella <andre@masella.no-ip.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
35 #include <asm/types.h>
37 #include "volume_id.h"
43 /* All these values are taken from ocfs2-tools's ocfs2_fs.h */
44 #define OCFS2_VOL_UUID_LEN 16
45 #define OCFS2_MAX_VOL_LABEL_LEN 64
46 #define OCFS2_SUPERBLOCK_OFFSET 0x2000
49 /* This is the superblock. The OCFS2 header files have structs in structs.
50 This is one has been simplified since we only care about the superblock.
53 struct ocfs2_super_block {
54 __u8 i_signature[8]; /* Signature for validation */
55 __u32 i_generation; /* Generation number */
56 __s16 i_suballoc_slot; /* Slot suballocator this inode belongs to */
57 __u16 i_suballoc_bit; /* Bit offset in suballocator block group */
59 __u32 i_clusters; /* Cluster count */
60 __u32 i_uid; /* Owner UID */
61 __u32 i_gid; /* Owning GID */
62 __u64 i_size; /* Size in bytes */
63 __u16 i_mode; /* File mode */
64 __u16 i_links_count; /* Links count */
65 __u32 i_flags; /* File flags */
66 __u64 i_atime; /* Access time */
67 __u64 i_ctime; /* Creation time */
68 __u64 i_mtime; /* Modification time */
69 __u64 i_dtime; /* Deletion time */
70 __u64 i_blkno; /* Offset on disk, in blocks */
71 __u64 i_last_eb_blk; /* Pointer to last extent block */
72 __u32 i_fs_generation; /* Generation per fs-instance */
77 __u64 i_pad1; /* Generic way to refer to this 64bit union */
78 /* Normally there is a union of the different block types, but we only care about the superblock. */
79 __u16 s_major_rev_level;
80 __u16 s_minor_rev_level;
82 __s16 s_max_mnt_count;
83 __u16 s_state; /* File system state */
84 __u16 s_errors; /* Behaviour when detecting errors */
85 __u32 s_checkinterval; /* Max time between checks */
86 __u64 s_lastcheck; /* Time of last check */
87 __u32 s_creator_os; /* OS */
88 __u32 s_feature_compat; /* Compatible feature set */
89 __u32 s_feature_incompat; /* Incompatible feature set */
90 __u32 s_feature_ro_compat; /* Readonly-compatible feature set */
91 __u64 s_root_blkno; /* Offset, in blocks, of root directory dinode */
92 __u64 s_system_dir_blkno; /* Offset, in blocks, of system directory dinode */
93 __u32 s_blocksize_bits; /* Blocksize for this fs */
94 __u32 s_clustersize_bits; /* Clustersize for this fs */
95 __u16 s_max_slots; /* Max number of simultaneous mounts before tunefs required */
98 __u64 s_first_cluster_group; /* Block offset of 1st cluster group header */
99 __u8 s_label[OCFS2_MAX_VOL_LABEL_LEN]; /* Label for mounting, etc. */
100 __u8 s_uuid[OCFS2_VOL_UUID_LEN]; /* 128-bit uuid */
101 } __attribute__((__packed__));
103 int volume_id_probe_ocfs2(struct volume_id *id, __u64 off)
105 struct ocfs2_super_block *os;
107 dbg("probing at offset 0x%llx", (unsigned long long) off);
109 os = (struct ocsf2_super_block *) volume_id_get_buffer(id, off + OCFS2_SUPERBLOCK_OFFSET, 0x200);
113 if (strcmp(os->i_signature, "OCFSV2") != 0) {
117 volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
118 volume_id_set_label_raw(id, os->s_label, OCFS2_MAX_VOL_LABEL_LEN < VOLUME_ID_LABEL_SIZE ?
119 OCFS2_MAX_VOL_LABEL_LEN : VOLUME_ID_LABEL_SIZE);
120 volume_id_set_label_string(id, os->s_label, OCFS2_MAX_VOL_LABEL_LEN < VOLUME_ID_LABEL_SIZE ?
121 OCFS2_MAX_VOL_LABEL_LEN : VOLUME_ID_LABEL_SIZE);
122 volume_id_set_uuid(id, os->s_uuid, UUID_DCE);