linux-imx

/*

 *   Copyright (C) International Business Machines Corp., 2000-2004

 *   Portions Copyright (C) Christoph Hellwig, 2001-2002

 *

 *   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_LOGMGR

#define _H_JFS_LOGMGR

​

#include "jfs_filsys.h"

#include "jfs_lock.h"

​

/*

 *  log manager configuration parameters

 */

​

/* log page size */

#define LOGPSIZE    4096

#define L2LOGPSIZE  12

​

#define LOGPAGES    16  /* Log pages per mounted file system */

​

/*

 *  log logical volume

 *

 * a log is used to make the commit operation on journalled

 * files within the same logical volume group atomic.

 * a log is implemented with a logical volume.

 * there is one log per logical volume group.

 *

 * block 0 of the log logical volume is not used (ipl etc).

 * block 1 contains a log "superblock" and is used by logFormat(),

 * lmLogInit(), lmLogShutdown(), and logRedo() to record status

 * of the log but is not otherwise used during normal processing.

 * blocks 2 - (N-1) are used to contain log records.

 *

 * when a volume group is varied-on-line, logRedo() must have

 * been executed before the file systems (logical volumes) in

 * the volume group can be mounted.

 */

/*

 *  log superblock (block 1 of logical volume)

 */

#define LOGSUPER_B  1

#define LOGSTART_B  2

​

#define LOGMAGIC    0x87654321

#define LOGVERSION  1

​

#define MAX_ACTIVE  128 /* Max active file systems sharing log */

​

struct logsuper {

    __le32 magic;       /* 4: log lv identifier */

    __le32 version;     /* 4: version number */

    __le32 serial;      /* 4: log open/mount counter */

    __le32 size;        /* 4: size in number of LOGPSIZE blocks */

    __le32 bsize;       /* 4: logical block size in byte */

    __le32 l2bsize;     /* 4: log2 of bsize */

​

    __le32 flag;        /* 4: option */

    __le32 state;       /* 4: state - see below */

​

    __le32 end;     /* 4: addr of last log record set by logredo */

    char uuid[16];      /* 16: 128-bit journal uuid */

    char label[16];     /* 16: journal label */

    struct {

        char uuid[16];

    } active[MAX_ACTIVE];   /* 2048: active file systems list */

};

​

#define NULL_UUID "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0"

​

/* log flag: commit option (see jfs_filsys.h) */

​

/* log state */

#define LOGMOUNT    0   /* log mounted by lmLogInit() */

#define LOGREDONE   1   /* log shutdown by lmLogShutdown().

                 * log redo completed by logredo().

                 */

#define LOGWRAP     2   /* log wrapped */