fstype/jfs_superblock.h

   1 /*
   2  *   Copyright (C) International Business Machines Corp., 2000-2003
   3  *
   4  *   This program is free software;  you can redistribute it and/or modify
   5  *   it under the terms of the GNU General Public License as published by
   6  *   the Free Software Foundation; either version 2 of the License, or
   7  *   (at your option) any later version.
   8  *
   9  *   This program is distributed in the hope that it will be useful,
  10  *   but WITHOUT ANY WARRANTY;  without even the implied warranty of
  11  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
  12  *   the GNU General Public License for more details.
  13  *
  14  *   You should have received a copy of the GNU General Public License
  15  *   along with this program;  if not, write to the Free Software
  16  *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  17  */
  18 #ifndef _H_JFS_SUPERBLOCK
  19 #define _H_JFS_SUPERBLOCK
  20
  21 struct timestruc_t {
  22         __le32 tv_sec;
  23         __le32 tv_nsec;
  24 };
  25
  26 /*
  27  * make the magic number something a human could read
  28  */
  29 #define JFS_MAGIC       "JFS1"  /* Magic word */
  30
  31 #define JFS_VERSION     2       /* Version number: Version 2 */
  32
  33 #define LV_NAME_SIZE    11      /* MUST BE 11 for OS/2 boot sector */
  34
  35 /*
  36  *      aggregate superblock
  37  *
  38  * The name superblock is too close to super_block, so the name has been
  39  * changed to jfs_superblock.  The utilities are still using the old name.
  40  */
  41 struct jfs_superblock {
  42         char s_magic[4];        /* 4: magic number */
  43         __le32 s_version;       /* 4: version number */
  44
  45         __le64 s_size;          /* 8: aggregate size in hardware/LVM blocks;
  46                                  * VFS: number of blocks
  47                                  */
  48         __le32 s_bsize;         /* 4: aggregate block size in bytes;
  49                                  * VFS: fragment size
  50                                  */
  51         __le16 s_l2bsize;       /* 2: log2 of s_bsize */
  52         __le16 s_l2bfactor;     /* 2: log2(s_bsize/hardware block size) */
  53         __le32 s_pbsize;        /* 4: hardware/LVM block size in bytes */
  54         __le16 s_l2pbsize;      /* 2: log2 of s_pbsize */
  55         __le16 pad;             /* 2: padding necessary for alignment */
  56
  57         __le32 s_agsize;        /* 4: allocation group size in aggr. blocks */
  58
  59         __le32 s_flag;          /* 4: aggregate attributes:
  60                                  *    see jfs_filsys.h
  61                                  */
  62         __le32 s_state;         /* 4: mount/unmount/recovery state:
  63                                  *    see jfs_filsys.h
  64                                  */
  65         __le32 s_compress;      /* 4: > 0 if data compression */
  66
  67         __le64 s_ait2;          /* 8: first extent of secondary
  68                                  *    aggregate inode table
  69                                  */
  70
  71         __le64 s_aim2;          /* 8: first extent of secondary
  72                                  *    aggregate inode map
  73                                  */
  74         __le32 s_logdev;        /* 4: device address of log */
  75         __le32 s_logserial;     /* 4: log serial number at aggregate mount */
  76         __le64 s_logpxd;        /* 8: inline log extent */
  77
  78         __le64 s_fsckpxd;       /* 8: inline fsck work space extent */
  79
  80         struct timestruc_t s_time;      /* 8: time last updated */
  81
  82         __le32 s_fsckloglen;    /* 4: Number of filesystem blocks reserved for
  83                                  *    the fsck service log.
  84                                  *    N.B. These blocks are divided among the
  85                                  *         versions kept.  This is not a per
  86                                  *         version size.
  87                                  *    N.B. These blocks are included in the
  88                                  *         length field of s_fsckpxd.
  89                                  */
  90         char s_fscklog;         /* 1: which fsck service log is most recent
  91                                  *    0 => no service log data yet
  92                                  *    1 => the first one
  93                                  *    2 => the 2nd one
  94                                  */
  95         char s_fpack[11];       /* 11: file system volume name
  96                                  *     N.B. This must be 11 bytes to
  97                                  *          conform with the OS/2 BootSector
  98                                  *          requirements
  99                                  *          Only used when s_version is 1
 100                                  */
 101
 102         /* extendfs() parameter under s_state & FM_EXTENDFS */
 103         __le64 s_xsize;         /* 8: extendfs s_size */
 104         __le64 s_xfsckpxd;      /* 8: extendfs fsckpxd */
 105         __le64 s_xlogpxd;       /* 8: extendfs logpxd */
 106         /* - 128 byte boundary - */
 107
 108         char s_uuid[16];        /* 16: 128-bit uuid for volume */
 109         char s_label[16];       /* 16: volume label */
 110         char s_loguuid[16];     /* 16: 128-bit uuid for log device */
 111
 112 };
 113
 114 #endif /*_H_JFS_SUPERBLOCK */