+++ /dev/null
-/* SPDX-License-Identifier: GPL-2.0-or-later */
-/*
- * logfile.h - Defines for NTFS kernel journal ($LogFile) handling. Part of
- * the Linux-NTFS project.
- *
- * Copyright (c) 2000-2005 Anton Altaparmakov
- */
-
-#ifndef _LINUX_NTFS_LOGFILE_H
-#define _LINUX_NTFS_LOGFILE_H
-
-#ifdef NTFS_RW
-
-#include <linux/fs.h>
-
-#include "types.h"
-#include "endian.h"
-#include "layout.h"
-
-/*
- * Journal ($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 */
projects / linux-2.6-microblaze.git / blobdiff