source: MondoRescue/branches/3.3/mindi-busybox/util-linux/volume_id/ocfs2.c@ 3621

/*
 * 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
 */

//kbuild:lib-$(CONFIG_FEATURE_VOLUMEID_OCFS2) += ocfs2.o

//config:
//config:config FEATURE_VOLUMEID_OCFS2
//config:   bool "ocfs2 filesystem"
//config:   default y
//config:   depends on VOLUMEID
//config:   help
//config:     TODO
//config:

#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 */
} PACKED;

int FAST_FUNC volume_id_probe_ocfs2(struct volume_id *id /*,uint64_t off*/)
{
#define off ((uint64_t)0)
    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);
    IF_FEATURE_BLKID_TYPE(id->type = "ocfs2";)
    return 0;
}