1/*
2 * usnjrnl.h - NTFS kernel transaction log ($UsnJrnl) handling.  Part of the
3 *	       Linux-NTFS project.
4 *
5 * Copyright (c) 2005 Anton Altaparmakov
6 *
7 * This program/include file is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License as published
9 * by the Free Software Foundation; either version 2 of the License, or
10 * (at your option) any later version.
11 *
12 * This program/include file is distributed in the hope that it will be
13 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
14 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program (in the main directory of the Linux-NTFS
19 * distribution in the file COPYING); if not, write to the Free Software
20 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
21 */
22
23#ifdef NTFS_RW
24
25#include <linux/fs.h>
26#include <linux/highmem.h>
27#include <linux/mm.h>
28
29#include "aops.h"
30#include "debug.h"
31#include "endian.h"
32#include "time.h"
33#include "types.h"
34#include "usnjrnl.h"
35#include "volume.h"
36
37/**
38 * ntfs_stamp_usnjrnl - stamp the transaction log ($UsnJrnl) on an ntfs volume
39 * @vol:	ntfs volume on which to stamp the transaction log
40 *
41 * Stamp the transaction log ($UsnJrnl) on the ntfs volume @vol and return
42 * 'true' on success and 'false' on error.
43 *
44 * This function assumes that the transaction log has already been loaded and
45 * consistency checked by a call to fs/ntfs/super.c::load_and_init_usnjrnl().
46 */
47bool ntfs_stamp_usnjrnl(ntfs_volume *vol)
48{
49	ntfs_debug("Entering.");
50	if (likely(!NVolUsnJrnlStamped(vol))) {
51		sle64 stamp;
52		struct page *page;
53		USN_HEADER *uh;
54
55		page = ntfs_map_page(vol->usnjrnl_max_ino->i_mapping, 0);
56		if (IS_ERR(page)) {
57			ntfs_error(vol->sb, "Failed to read from "
58					"$UsnJrnl/$DATA/$Max attribute.");
59			return false;
60		}
61		uh = (USN_HEADER*)page_address(page);
62		stamp = get_current_ntfs_time();
63		ntfs_debug("Stamping transaction log ($UsnJrnl): old "
64				"journal_id 0x%llx, old lowest_valid_usn "
65				"0x%llx, new journal_id 0x%llx, new "
66				"lowest_valid_usn 0x%llx.",
67				(long long)sle64_to_cpu(uh->journal_id),
68				(long long)sle64_to_cpu(uh->lowest_valid_usn),
69				(long long)sle64_to_cpu(stamp),
70				i_size_read(vol->usnjrnl_j_ino));
71		uh->lowest_valid_usn =
72				cpu_to_sle64(i_size_read(vol->usnjrnl_j_ino));
73		uh->journal_id = stamp;
74		flush_dcache_page(page);
75		set_page_dirty(page);
76		ntfs_unmap_page(page);
77		/* Set the flag so we do not have to do it again on remount. */
78		NVolSetUsnJrnlStamped(vol);
79	}
80	ntfs_debug("Done.");
81	return true;
82}
83
84#endif /* NTFS_RW */
85