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jfs_superblock.h
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/*
* Copyright (c) International Business Machines Corp., 2000
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 3 of the License, or
* (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef _H_JFS_SUPERBLOCK
#define _H_JFS_SUPERBLOCK
/*
* jfs_superblock.h
*/
/*
* make the magic number something a human could read
*/
#define JFS_MAGIC "JFS1" /* Magic word: Version 1 */
#define JFS_VERSION 1 /* Version number: Version 1 */
#define LV_NAME_SIZE 11 /* MUST BE 11 for OS/2 boot sector */
/*
* aggregate superblock
*
* The name superblock is too close to super_block, so the name has been
* changed to jfs_superblock. The utilities are still using the old name.
*/
#ifdef _JFS_UTILITY
struct superblock
#else
struct jfs_superblock
#endif
{
char s_magic[4]; /* 4: magic number */
u32 s_version; /* 4: version number */
s64 s_size; /* 8: aggregate size in hardware/LVM blocks;
* VFS: number of blocks
*/
s32 s_bsize; /* 4: aggregate block size in bytes;
* VFS: fragment size
*/
s16 s_l2bsize; /* 2: log2 of s_bsize */
s16 s_l2bfactor; /* 2: log2(s_bsize/hardware block size) */
s32 s_pbsize; /* 4: hardware/LVM block size in bytes */
s16 s_l2pbsize; /* 2: log2 of s_pbsize */
s16 pad; /* 2: padding necessary for alignment */
u32 s_agsize; /* 4: allocation group size in aggr. blocks */
u32 s_flag; /* 4: aggregate attributes:
* see jfs_filsys.h
*/
u32 s_state; /* 4: mount/unmount/recovery state:
* see jfs_filsys.h
*/
s32 s_compress; /* 4: > 0 if data compression */
pxd_t s_ait2; /* 8: first extent of secondary
* aggregate inode table
*/
pxd_t s_aim2; /* 8: first extent of secondary
* aggregate inode map
*/
u32 s_logdev; /* 4: device address of log */
s32 s_logserial; /* 4: log serial number at aggregate mount */
pxd_t s_logpxd; /* 8: inline log extent */
pxd_t s_fsckpxd; /* 8: inline fsck work space extent */
struct timestruc_t s_time; /* 8: time last updated */
s32 s_fsckloglen; /* 4: Number of file system blocks reserved for
* the fsck service log.
* N.B. These blocks are divided among the
* versions kept. This is not a per
* version size.
* N.B. These blocks are included in the
* length field of s_fsckpxd.
*/
s8 s_fscklog; /* 1: which fsck service log is most recent
* 0 => no service log data yet
* 1 => the first one
* 2 => the 2nd one
*/
char s_fpack[11]; /* 11: file system volume name
* N.B. This must be 11 bytes to
* conform with the OS/2 BootSector
* requirements
*/
/* extendfs() parameter under s_state & FM_EXTENDFS */
s64 s_xsize; /* 8: extendfs s_size */
pxd_t s_xfsckpxd; /* 8: extendfs fsckpxd */
pxd_t s_xlogpxd; /* 8: extendfs logpxd */
/* - 128 byte boundary - */
/*
* DFS VFS support (preliminary)
*/
char s_attach; /* 1: VFS: flag: set when aggregate is attached
*/
u8 rsrvd4[7]; /* 7: reserved - set to 0 */
u64 totalUsable; /* 8: VFS: total of 1K blocks which are
* available to "normal" (non-root) users.
*/
u64 minFree; /* 8: VFS: # of 1K blocks held in reserve for
* exclusive use of root. This value can be 0,
* and if it is then totalUsable will be equal
* to # of blocks in aggregate. I believe this
* means that minFree + totalUsable = # blocks.
* In that case, we don't need to store both
* totalUsable and minFree since we can compute
* one from the other. I would guess minFree
* would be the one we should store, and
* totalUsable would be the one we should
* compute. (Just a guess...)
*/
u64 realFree; /* 8: VFS: # of free 1K blocks can be used by
* "normal" users. It may be this is something
* we should compute when asked for instead of
* storing in the superblock. I don't know how
* often this information is needed.
*/
/*
* graffiti area
*/
};
#endif /*_H_JFS_SUPERBLOCK */
jfs_superblock
Definition jfs_superblock.h:44
jfs_superblock::s_flag
u32 s_flag
Definition jfs_superblock.h:62
jfs_superblock::s_xlogpxd
pxd_t s_xlogpxd
Definition jfs_superblock.h:107
jfs_superblock::s_xfsckpxd
pxd_t s_xfsckpxd
Definition jfs_superblock.h:106
jfs_superblock::s_aim2
pxd_t s_aim2
Definition jfs_superblock.h:74
jfs_superblock::s_l2bfactor
s16 s_l2bfactor
Definition jfs_superblock.h:55
jfs_superblock::realFree
u64 realFree
Definition jfs_superblock.h:133
jfs_superblock::s_logdev
u32 s_logdev
Definition jfs_superblock.h:77
jfs_superblock::s_fpack
char s_fpack[11]
Definition jfs_superblock.h:98
jfs_superblock::s_logserial
s32 s_logserial
Definition jfs_superblock.h:78
jfs_superblock::s_state
u32 s_state
Definition jfs_superblock.h:65
jfs_superblock::s_agsize
u32 s_agsize
Definition jfs_superblock.h:60
jfs_superblock::pad
s16 pad
Definition jfs_superblock.h:58
jfs_superblock::s_logpxd
pxd_t s_logpxd
Definition jfs_superblock.h:79
jfs_superblock::s_attach
char s_attach
Definition jfs_superblock.h:113
jfs_superblock::s_l2pbsize
s16 s_l2pbsize
Definition jfs_superblock.h:57
jfs_superblock::s_size
s64 s_size
Definition jfs_superblock.h:48
jfs_superblock::minFree
u64 minFree
Definition jfs_superblock.h:120
jfs_superblock::s_pbsize
s32 s_pbsize
Definition jfs_superblock.h:56
jfs_superblock::s_time
struct timestruc_t s_time
Definition jfs_superblock.h:83
jfs_superblock::s_ait2
pxd_t s_ait2
Definition jfs_superblock.h:70
jfs_superblock::s_compress
s32 s_compress
Definition jfs_superblock.h:68
jfs_superblock::s_bsize
s32 s_bsize
Definition jfs_superblock.h:51
jfs_superblock::s_l2bsize
s16 s_l2bsize
Definition jfs_superblock.h:54
jfs_superblock::rsrvd4
u8 rsrvd4[7]
Definition jfs_superblock.h:115
jfs_superblock::totalUsable
u64 totalUsable
Definition jfs_superblock.h:117
jfs_superblock::s_magic
char s_magic[4]
Definition jfs_superblock.h:45
jfs_superblock::s_fsckpxd
pxd_t s_fsckpxd
Definition jfs_superblock.h:81
jfs_superblock::s_fsckloglen
s32 s_fsckloglen
Definition jfs_superblock.h:85
jfs_superblock::s_version
u32 s_version
Definition jfs_superblock.h:46
jfs_superblock::s_fscklog
s8 s_fscklog
Definition jfs_superblock.h:93
jfs_superblock::s_xsize
s64 s_xsize
Definition jfs_superblock.h:105
pxd_t
Definition jfs_types.h:151
timestruc_t
Definition jfs_types.h:96