jfs_superblock.h

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/*
 *   Copyright (C) International Business Machines Corp., 2000-2003
 *
 *   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 2 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, write to the Free Software
 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
#ifndef _H_JFS_SUPERBLOCK
#define _H_JFS_SUPERBLOCK

/*
 * make the magic number something a human could read
 */
#define JFS_MAGIC   "JFS1"  /* Magic word */

#define JFS_VERSION 2   /* Version number: Version 2 */

#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.
 */
struct jfs_superblock {
    char s_magic[4];    /* 4: magic number */
    __le32 s_version;   /* 4: version number */

    __le64 s_size;      /* 8: aggregate size in hardware/LVM blocks;
                 * VFS: number of blocks
                 */
    __le32 s_bsize;     /* 4: aggregate block size in bytes;
                 * VFS: fragment size
                 */
    __le16 s_l2bsize;   /* 2: log2 of s_bsize */
    __le16 s_l2bfactor; /* 2: log2(s_bsize/hardware block size) */
    __le32 s_pbsize;    /* 4: hardware/LVM block size in bytes */
    __le16 s_l2pbsize;  /* 2: log2 of s_pbsize */
    __le16 pad;     /* 2: padding necessary for alignment */

    __le32 s_agsize;    /* 4: allocation group size in aggr. blocks */

    __le32 s_flag;      /* 4: aggregate attributes:
                 *    see jfs_filsys.h
                 */
    __le32 s_state;     /* 4: mount/unmount/recovery state:
                 *    see jfs_filsys.h
                 */
    __le32 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
                 */
    __le32 s_logdev;        /* 4: device address of log */
    __le32 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 */

    __le32 s_fsckloglen;    /* 4: Number of filesystem 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
                 *          Only used when s_version is 1
                 */

    /* extendfs() parameter under s_state & FM_EXTENDFS */
    __le64 s_xsize;     /* 8: extendfs s_size */
    pxd_t s_xfsckpxd;   /* 8: extendfs fsckpxd */
    pxd_t s_xlogpxd;    /* 8: extendfs logpxd */
    /* - 128 byte boundary - */

    char s_uuid[16];    /* 16: 128-bit uuid for volume */
    char s_label[16];   /* 16: volume label */
    char s_loguuid[16]; /* 16: 128-bit uuid for log device */

};

extern int readSuper(struct super_block *, struct buffer_head **);
extern int updateSuper(struct super_block *, uint);
extern void jfs_error(struct super_block *, const char *, ...);
extern int jfs_mount(struct super_block *);
extern int jfs_mount_rw(struct super_block *, int);
extern int jfs_umount(struct super_block *);
extern int jfs_umount_rw(struct super_block *);
extern int jfs_extendfs(struct super_block *, s64, int);

extern struct task_struct *jfsIOthread;
extern struct task_struct *jfsSyncThread;

#endif /*_H_JFS_SUPERBLOCK */