xref: /kernel/linux/linux-5.10/fs/ntfs/usnjrnl.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * usnjrnl.h - NTFS kernel transaction log ($UsnJrnl) handling.  Part of the
4 *	       Linux-NTFS project.
5 *
6 * Copyright (c) 2005 Anton Altaparmakov
7 */
8
9#ifdef NTFS_RW
10
11#include <linux/fs.h>
12#include <linux/highmem.h>
13#include <linux/mm.h>
14
15#include "aops.h"
16#include "debug.h"
17#include "endian.h"
18#include "time.h"
19#include "types.h"
20#include "usnjrnl.h"
21#include "volume.h"
22
23/**
24 * ntfs_stamp_usnjrnl - stamp the transaction log ($UsnJrnl) on an ntfs volume
25 * @vol:	ntfs volume on which to stamp the transaction log
26 *
27 * Stamp the transaction log ($UsnJrnl) on the ntfs volume @vol and return
28 * 'true' on success and 'false' on error.
29 *
30 * This function assumes that the transaction log has already been loaded and
31 * consistency checked by a call to fs/ntfs/super.c::load_and_init_usnjrnl().
32 */
33bool ntfs_stamp_usnjrnl(ntfs_volume *vol)
34{
35	ntfs_debug("Entering.");
36	if (likely(!NVolUsnJrnlStamped(vol))) {
37		sle64 stamp;
38		struct page *page;
39		USN_HEADER *uh;
40
41		page = ntfs_map_page(vol->usnjrnl_max_ino->i_mapping, 0);
42		if (IS_ERR(page)) {
43			ntfs_error(vol->sb, "Failed to read from "
44					"$UsnJrnl/$DATA/$Max attribute.");
45			return false;
46		}
47		uh = (USN_HEADER*)page_address(page);
48		stamp = get_current_ntfs_time();
49		ntfs_debug("Stamping transaction log ($UsnJrnl): old "
50				"journal_id 0x%llx, old lowest_valid_usn "
51				"0x%llx, new journal_id 0x%llx, new "
52				"lowest_valid_usn 0x%llx.",
53				(long long)sle64_to_cpu(uh->journal_id),
54				(long long)sle64_to_cpu(uh->lowest_valid_usn),
55				(long long)sle64_to_cpu(stamp),
56				i_size_read(vol->usnjrnl_j_ino));
57		uh->lowest_valid_usn =
58				cpu_to_sle64(i_size_read(vol->usnjrnl_j_ino));
59		uh->journal_id = stamp;
60		flush_dcache_page(page);
61		set_page_dirty(page);
62		ntfs_unmap_page(page);
63		/* Set the flag so we do not have to do it again on remount. */
64		NVolSetUsnJrnlStamped(vol);
65	}
66	ntfs_debug("Done.");
67	return true;
68}
69
70#endif /* NTFS_RW */
71