busybox/util-linux/volume_id/ocfs2.c
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   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.
  30This is one has been simplified since we only care about the superblock.
  31*/
  32
  33struct 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} PACKED;
  82
  83int FAST_FUNC volume_id_probe_ocfs2(struct volume_id *id /*,uint64_t off*/)
  84{
  85#define off ((uint64_t)0)
  86        struct ocfs2_super_block *os;
  87
  88        dbg("probing at offset 0x%llx", (unsigned long long) off);
  89
  90        os = volume_id_get_buffer(id, off + OCFS2_SUPERBLOCK_OFFSET, 0x200);
  91        if (os == NULL)
  92                return -1;
  93
  94        if (memcmp(os->i_signature, "OCFSV2", 6) != 0) {
  95                return -1;
  96        }
  97
  98//      volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
  99//      volume_id_set_label_raw(id, os->s_label, OCFS2_MAX_VOL_LABEL_LEN < VOLUME_ID_LABEL_SIZE ?
 100//                                      OCFS2_MAX_VOL_LABEL_LEN : VOLUME_ID_LABEL_SIZE);
 101        volume_id_set_label_string(id, os->s_label, OCFS2_MAX_VOL_LABEL_LEN < VOLUME_ID_LABEL_SIZE ?
 102                                        OCFS2_MAX_VOL_LABEL_LEN : VOLUME_ID_LABEL_SIZE);
 103        volume_id_set_uuid(id, os->s_uuid, UUID_DCE);
 104//      id->type = "ocfs2";
 105        return 0;
 106}
 107