busybox/util-linux/volume_id/ocfs2.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

106 lines
4.3 KiB
C

/*
* volume_id - reads filesystem label and uuid
*
* Copyright (C) Andre Masella <andre@masella.no-ip.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"
/* All these values are taken from ocfs2-tools's ocfs2_fs.h */
#define OCFS2_VOL_UUID_LEN 16
#define OCFS2_MAX_VOL_LABEL_LEN 64
#define OCFS2_SUPERBLOCK_OFFSET 0x2000
/* This is the superblock. The OCFS2 header files have structs in structs.
This is one has been simplified since we only care about the superblock.
*/
struct ocfs2_super_block {
uint8_t i_signature[8]; /* Signature for validation */
uint32_t i_generation; /* Generation number */
int16_t i_suballoc_slot; /* Slot suballocator this inode belongs to */
uint16_t i_suballoc_bit; /* Bit offset in suballocator block group */
uint32_t i_reserved0;
uint32_t i_clusters; /* Cluster count */
uint32_t i_uid; /* Owner UID */
uint32_t i_gid; /* Owning GID */
uint64_t i_size; /* Size in bytes */
uint16_t i_mode; /* File mode */
uint16_t i_links_count; /* Links count */
uint32_t i_flags; /* File flags */
uint64_t i_atime; /* Access time */
uint64_t i_ctime; /* Creation time */
uint64_t i_mtime; /* Modification time */
uint64_t i_dtime; /* Deletion time */
uint64_t i_blkno; /* Offset on disk, in blocks */
uint64_t i_last_eb_blk; /* Pointer to last extent block */
uint32_t i_fs_generation; /* Generation per fs-instance */
uint32_t i_atime_nsec;
uint32_t i_ctime_nsec;
uint32_t i_mtime_nsec;
uint64_t i_reserved1[9];
uint64_t i_pad1; /* Generic way to refer to this 64bit union */
/* Normally there is a union of the different block types, but we only care about the superblock. */
uint16_t s_major_rev_level;
uint16_t s_minor_rev_level;
uint16_t s_mnt_count;
int16_t s_max_mnt_count;
uint16_t s_state; /* File system state */
uint16_t s_errors; /* Behaviour when detecting errors */
uint32_t s_checkinterval; /* Max time between checks */
uint64_t s_lastcheck; /* Time of last check */
uint32_t s_creator_os; /* OS */
uint32_t s_feature_compat; /* Compatible feature set */
uint32_t s_feature_incompat; /* Incompatible feature set */
uint32_t s_feature_ro_compat; /* Readonly-compatible feature set */
uint64_t s_root_blkno; /* Offset, in blocks, of root directory dinode */
uint64_t s_system_dir_blkno; /* Offset, in blocks, of system directory dinode */
uint32_t s_blocksize_bits; /* Blocksize for this fs */
uint32_t s_clustersize_bits; /* Clustersize for this fs */
uint16_t s_max_slots; /* Max number of simultaneous mounts before tunefs required */
uint16_t s_reserved1;
uint32_t s_reserved2;
uint64_t s_first_cluster_group; /* Block offset of 1st cluster group header */
uint8_t s_label[OCFS2_MAX_VOL_LABEL_LEN]; /* Label for mounting, etc. */
uint8_t s_uuid[OCFS2_VOL_UUID_LEN]; /* 128-bit uuid */
} __attribute__((__packed__));
int volume_id_probe_ocfs2(struct volume_id *id, uint64_t off)
{
struct ocfs2_super_block *os;
dbg("probing at offset 0x%llx", (unsigned long long) off);
os = volume_id_get_buffer(id, off + OCFS2_SUPERBLOCK_OFFSET, 0x200);
if (os == NULL)
return -1;
if (memcmp(os->i_signature, "OCFSV2", 6) != 0) {
return -1;
}
volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
volume_id_set_label_raw(id, os->s_label, OCFS2_MAX_VOL_LABEL_LEN < VOLUME_ID_LABEL_SIZE ?
OCFS2_MAX_VOL_LABEL_LEN : VOLUME_ID_LABEL_SIZE);
volume_id_set_label_string(id, os->s_label, OCFS2_MAX_VOL_LABEL_LEN < VOLUME_ID_LABEL_SIZE ?
OCFS2_MAX_VOL_LABEL_LEN : VOLUME_ID_LABEL_SIZE);
volume_id_set_uuid(id, os->s_uuid, UUID_DCE);
id->type = "ocfs2";
return 0;
}