cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

usnjrnl.c (1969B)

      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 */