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diff --git a/fs/ntfs/logfile.h b/fs/ntfs/logfile.h
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+/*
+ * logfile.h - Defines for NTFS kernel journal ($LogFile) handling.  Part of
+ *	       the Linux-NTFS project.
+ *
+ * Copyright (c) 2000-2005 Anton Altaparmakov
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifndef _LINUX_NTFS_LOGFILE_H
+#define _LINUX_NTFS_LOGFILE_H
+
+#ifdef NTFS_RW
+
+#include <linux/fs.h>
+
+#include "types.h"
+#include "endian.h"
+#include "layout.h"
+
+/*
+ * Journal ($LogFile) organization:
+ *
+ * Two restart areas present in the first two pages (restart pages, one restart
+ * area in each page).  When the volume is dismounted they should be identical,
+ * except for the update sequence array which usually has a different update
+ * sequence number.
+ *
+ * These are followed by log records organized in pages headed by a log record
+ * header going up to log file size.  Not all pages contain log records when a
+ * volume is first formatted, but as the volume ages, all records will be used.
+ * When the log file fills up, the records at the beginning are purged (by
+ * modifying the oldest_lsn to a higher value presumably) and writing begins
+ * at the beginning of the file.  Effectively, the log file is viewed as a
+ * circular entity.
+ *
+ * NOTE: Windows NT, 2000, and XP all use log file version 1.1 but they accept
+ * versions <= 1.x, including 0.-1.  (Yes, that is a minus one in there!)  We
+ * probably only want to support 1.1 as this seems to be the current version
+ * and we don't know how that differs from the older versions.  The only
+ * exception is if the journal is clean as marked by the two restart pages
+ * then it doesn't matter whether we are on an earlier version.  We can just
+ * reinitialize the logfile and start again with version 1.1.
+ */
+
+/* Some $LogFile related constants. */
+#define MaxLogFileSize		0x100000000ULL
+#define DefaultLogPageSize	4096
+#define MinLogRecordPages	48
+
+/*
+ * Log file restart page header (begins the restart area).
+ */
+typedef struct {
+/*Ofs*/
+/*  0	NTFS_RECORD; -- Unfolded here as gcc doesn't like unnamed structs. */
+/*  0*/	NTFS_RECORD_TYPE magic;	/* The magic is "RSTR". */
+/*  4*/	le16 usa_ofs;		/* See NTFS_RECORD definition in layout.h.
+				   When creating, set this to be immediately
+				   after this header structure (without any
+				   alignment). */
+/*  6*/	le16 usa_count;		/* See NTFS_RECORD definition in layout.h. */
+
+/*  8*/	leLSN chkdsk_lsn;	/* The last log file sequence number found by
+				   chkdsk.  Only used when the magic is changed
+				   to "CHKD".  Otherwise this is zero. */
+/* 16*/	le32 system_page_size;	/* Byte size of system pages when the log file
+				   was created, has to be >= 512 and a power of
+				   2.  Use this to calculate the required size
+				   of the usa (usa_count) and add it to usa_ofs.
+				   Then verify that the result is less than the
+				   value of the restart_area_offset. */
+/* 20*/	le32 log_page_size;	/* Byte size of log file pages, has to be >=
+				   512 and a power of 2.  The default is 4096
+				   and is used when the system page size is
+				   between 4096 and 8192.  Otherwise this is
+				   set to the system page size instead. */
+/* 24*/	le16 restart_area_offset;/* Byte offset from the start of this header to
+				   the RESTART_AREA.  Value has to be aligned
+				   to 8-byte boundary.  When creating, set this
+				   to be after the usa. */
+/* 26*/	sle16 minor_ver;	/* Log file minor version.  Only check if major
+				   version is 1. */
+/* 28*/	sle16 major_ver;	/* Log file major version.  We only support
+				   version 1.1. */
+/* sizeof() = 30 (0x1e) bytes */
+} __attribute__ ((__packed__)) RESTART_PAGE_HEADER;
+
+/*
+ * Constant for the log client indices meaning that there are no client records
+ * in this particular client array.  Also inside the client records themselves,
+ * this means that there are no client records preceding or following this one.
+ */
+#define LOGFILE_NO_CLIENT	cpu_to_le16(0xffff)
+#define LOGFILE_NO_CLIENT_CPU	0xffff
+
+/*
+ * These are the so far known RESTART_AREA_* flags (16-bit) which contain
+ * information about the log file in which they are present.
+ */
+enum {
+	RESTART_VOLUME_IS_CLEAN	= cpu_to_le16(0x0002),
+	RESTART_SPACE_FILLER	= cpu_to_le16(0xffff), /* gcc: Force enum bit width to 16. */
+} __attribute__ ((__packed__));
+
+typedef le16 RESTART_AREA_FLAGS;
+
+/*
+ * Log file restart area record.  The offset of this record is found by adding
+ * the offset of the RESTART_PAGE_HEADER to the restart_area_offset value found
+ * in it.  See notes at restart_area_offset above.
+ */
+typedef struct {
+/*Ofs*/
+/*  0*/	leLSN current_lsn;	/* The current, i.e. last LSN inside the log
+				   when the restart area was last written.
+				   This happens often but what is the interval?
+				   Is it just fixed time or is it every time a
+				   check point is written or somethine else?
+				   On create set to 0. */
+/*  8*/	le16 log_clients;	/* Number of log client records in the array of
+				   log client records which follows this
+				   restart area.  Must be 1.  */
+/* 10*/	le16 client_free_list;	/* The index of the first free log client record
+				   in the array of log client records.
+				   LOGFILE_NO_CLIENT means that there are no
+				   free log client records in the array.
+				   If != LOGFILE_NO_CLIENT, check that
+				   log_clients > client_free_list.  On Win2k
+				   and presumably earlier, on a clean volume
+				   this is != LOGFILE_NO_CLIENT, and it should
+				   be 0, i.e. the first (and only) client
+				   record is free and thus the logfile is
+				   closed and hence clean.  A dirty volume
+				   would have left the logfile open and hence
+				   this would be LOGFILE_NO_CLIENT.  On WinXP
+				   and presumably later, the logfile is always
+				   open, even on clean shutdown so this should
+				   always be LOGFILE_NO_CLIENT. */
+/* 12*/	le16 client_in_use_list;/* The index of the first in-use log client
+				   record in the array of log client records.
+				   LOGFILE_NO_CLIENT means that there are no
+				   in-use log client records in the array.  If
+				   != LOGFILE_NO_CLIENT check that log_clients
+				   > client_in_use_list.  On Win2k and
+				   presumably earlier, on a clean volume this
+				   is LOGFILE_NO_CLIENT, i.e. there are no
+				   client records in use and thus the logfile
+				   is closed and hence clean.  A dirty volume
+				   would have left the logfile open and hence
+				   this would be != LOGFILE_NO_CLIENT, and it
+				   should be 0, i.e. the first (and only)
+				   client record is in use.  On WinXP and
+				   presumably later, the logfile is always
+				   open, even on clean shutdown so this should
+				   always be 0. */
+/* 14*/	RESTART_AREA_FLAGS flags;/* Flags modifying LFS behaviour.  On Win2k
+				   and presumably earlier this is always 0.  On
+				   WinXP and presumably later, if the logfile
+				   was shutdown cleanly, the second bit,
+				   RESTART_VOLUME_IS_CLEAN, is set.  This bit
+				   is cleared when the volume is mounted by
+				   WinXP and set when the volume is dismounted,
+				   thus if the logfile is dirty, this bit is
+				   clear.  Thus we don't need to check the
+				   Windows version to determine if the logfile
+				   is clean.  Instead if the logfile is closed,
+				   we know it must be clean.  If it is open and
+				   this bit is set, we also know it must be
+				   clean.  If on the other hand the logfile is
+				   open and this bit is clear, we can be almost
+				   certain that the logfile is dirty. */
+/* 16*/	le32 seq_number_bits;	/* How many bits to use for the sequence
+				   number.  This is calculated as 67 - the
+				   number of bits required to store the logfile
+				   size in bytes and this can be used in with
+				   the specified file_size as a consistency
+				   check. */
+/* 20*/	le16 restart_area_length;/* Length of the restart area including the
+				   client array.  Following checks required if
+				   version matches.  Otherwise, skip them.
+				   restart_area_offset + restart_area_length
+				   has to be <= system_page_size.  Also,
+				   restart_area_length has to be >=
+				   client_array_offset + (log_clients *
+				   sizeof(log client record)). */
+/* 22*/	le16 client_array_offset;/* Offset from the start of this record to
+				   the first log client record if versions are
+				   matched.  When creating, set this to be
+				   after this restart area structure, aligned
+				   to 8-bytes boundary.  If the versions do not
+				   match, this is ignored and the offset is
+				   assumed to be (sizeof(RESTART_AREA) + 7) &
+				   ~7, i.e. rounded up to first 8-byte
+				   boundary.  Either way, client_array_offset
+				   has to be aligned to an 8-byte boundary.
+				   Also, restart_area_offset +
+				   client_array_offset has to be <= 510.
+				   Finally, client_array_offset + (log_clients
+				   * sizeof(log client record)) has to be <=
+				   system_page_size.  On Win2k and presumably
+				   earlier, this is 0x30, i.e. immediately
+				   following this record.  On WinXP and
+				   presumably later, this is 0x40, i.e. there
+				   are 16 extra bytes between this record and
+				   the client array.  This probably means that
+				   the RESTART_AREA record is actually bigger
+				   in WinXP and later. */
+/* 24*/	sle64 file_size;	/* Usable byte size of the log file.  If the
+				   restart_area_offset + the offset of the
+				   file_size are > 510 then corruption has
+				   occurred.  This is the very first check when
+				   starting with the restart_area as if it
+				   fails it means that some of the above values
+				   will be corrupted by the multi sector
+				   transfer protection.  The file_size has to
+				   be rounded down to be a multiple of the
+				   log_page_size in the RESTART_PAGE_HEADER and
+				   then it has to be at least big enough to
+				   store the two restart pages and 48 (0x30)
+				   log record pages. */
+/* 32*/	le32 last_lsn_data_length;/* Length of data of last LSN, not including
+				   the log record header.  On create set to
+				   0. */
+/* 36*/	le16 log_record_header_length;/* Byte size of the log record header.
+				   If the version matches then check that the
+				   value of log_record_header_length is a
+				   multiple of 8, i.e.
+				   (log_record_header_length + 7) & ~7 ==
+				   log_record_header_length.  When creating set
+				   it to sizeof(LOG_RECORD_HEADER), aligned to
+				   8 bytes. */
+/* 38*/	le16 log_page_data_offset;/* Offset to the start of data in a log record
+				   page.  Must be a multiple of 8.  On create
+				   set it to immediately after the update
+				   sequence array of the log record page. */
+/* 40*/	le32 restart_log_open_count;/* A counter that gets incremented every
+				   time the logfile is restarted which happens
+				   at mount time when the logfile is opened.
+				   When creating set to a random value.  Win2k
+				   sets it to the low 32 bits of the current
+				   system time in NTFS format (see time.h). */
+/* 44*/	le32 reserved;		/* Reserved/alignment to 8-byte boundary. */
+/* sizeof() = 48 (0x30) bytes */
+} __attribute__ ((__packed__)) RESTART_AREA;
+
+/*
+ * Log client record.  The offset of this record is found by adding the offset
+ * of the RESTART_AREA to the client_array_offset value found in it.
+ */
+typedef struct {
+/*Ofs*/
+/*  0*/	leLSN oldest_lsn;	/* Oldest LSN needed by this client.  On create
+				   set to 0. */
+/*  8*/	leLSN client_restart_lsn;/* LSN at which this client needs to restart
+				   the volume, i.e. the current position within
+				   the log file.  At present, if clean this
+				   should = current_lsn in restart area but it
+				   probably also = current_lsn when dirty most
+				   of the time.  At create set to 0. */
+/* 16*/	le16 prev_client;	/* The offset to the previous log client record
+				   in the array of log client records.
+				   LOGFILE_NO_CLIENT means there is no previous
+				   client record, i.e. this is the first one.
+				   This is always LOGFILE_NO_CLIENT. */
+/* 18*/	le16 next_client;	/* The offset to the next log client record in
+				   the array of log client records.
+				   LOGFILE_NO_CLIENT means there are no next
+				   client records, i.e. this is the last one.
+				   This is always LOGFILE_NO_CLIENT. */
+/* 20*/	le16 seq_number;	/* On Win2k and presumably earlier, this is set
+				   to zero every time the logfile is restarted
+				   and it is incremented when the logfile is
+				   closed at dismount time.  Thus it is 0 when
+				   dirty and 1 when clean.  On WinXP and
+				   presumably later, this is always 0. */
+/* 22*/	u8 reserved[6];		/* Reserved/alignment. */
+/* 28*/	le32 client_name_length;/* Length of client name in bytes.  Should
+				   always be 8. */
+/* 32*/	ntfschar client_name[64];/* Name of the client in Unicode.  Should
+				   always be "NTFS" with the remaining bytes
+				   set to 0. */
+/* sizeof() = 160 (0xa0) bytes */
+} __attribute__ ((__packed__)) LOG_CLIENT_RECORD;
+
+extern bool ntfs_check_logfile(struct inode *log_vi,
+		RESTART_PAGE_HEADER **rp);
+
+extern bool ntfs_is_logfile_clean(struct inode *log_vi,
+		const RESTART_PAGE_HEADER *rp);
+
+extern bool ntfs_empty_logfile(struct inode *log_vi);
+
+#endif /* NTFS_RW */
+
+#endif /* _LINUX_NTFS_LOGFILE_H */