NTFS: Stamp the transaction log ($UsnJrnl), aka user space journal, if it

[pandora-kernel.git] / fs / ntfs / usnjrnl.c

diff --git a/fs/ntfs/usnjrnl.c b/fs/ntfs/usnjrnl.c
new file mode 100644 (file)
index 0000000..7777324
--- /dev/null
+++ b/fs/ntfs/usnjrnl.c
@@ -0,0 +1,84 @@
+/*
+ * usnjrnl.h - NTFS kernel transaction log ($UsnJrnl) handling.  Part of the
+ *            Linux-NTFS project.
+ *
+ * Copyright (c) 2005 Anton Altaparmakov
+ *
+ * This program/include file is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program/include file is distributed in the hope that it will be
+ * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program (in the main directory of the Linux-NTFS
+ * distribution in the file COPYING); if not, write to the Free Software
+ * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#ifdef NTFS_RW
+
+#include <linux/fs.h>
+#include <linux/highmem.h>
+#include <linux/mm.h>
+
+#include "aops.h"
+#include "debug.h"
+#include "endian.h"
+#include "time.h"
+#include "types.h"
+#include "usnjrnl.h"
+#include "volume.h"
+
+/**
+ * ntfs_stamp_usnjrnl - stamp the transaction log ($UsnJrnl) on an ntfs volume
+ * @vol:       ntfs volume on which to stamp the transaction log
+ *
+ * Stamp the transaction log ($UsnJrnl) on the ntfs volume @vol and return
+ * TRUE on success and FALSE on error.
+ *
+ * This function assumes that the transaction log has already been loaded and
+ * consistency checked by a call to fs/ntfs/super.c::load_and_init_usnjrnl().
+ */
+BOOL ntfs_stamp_usnjrnl(ntfs_volume *vol)
+{
+       ntfs_debug("Entering.");
+       if (likely(!NVolUsnJrnlStamped(vol))) {
+               sle64 stamp;
+               struct page *page;
+               USN_HEADER *uh;
+
+               page = ntfs_map_page(vol->usnjrnl_max_ino->i_mapping, 0);
+               if (IS_ERR(page)) {
+                       ntfs_error(vol->sb, "Failed to read from "
+                                       "$UsnJrnl/$DATA/$Max attribute.");
+                       return FALSE;
+               }
+               uh = (USN_HEADER*)page_address(page);
+               stamp = get_current_ntfs_time();
+               ntfs_debug("Stamping transaction log ($UsnJrnl): old "
+                               "journal_id 0x%llx, old lowest_valid_usn "
+                               "0x%llx, new journal_id 0x%llx, new "
+                               "lowest_valid_usn 0x%llx.",
+                               (long long)sle64_to_cpu(uh->journal_id),
+                               (long long)sle64_to_cpu(uh->lowest_valid_usn),
+                               (long long)sle64_to_cpu(stamp),
+                               i_size_read(vol->usnjrnl_j_ino));
+               uh->lowest_valid_usn =
+                               cpu_to_sle64(i_size_read(vol->usnjrnl_j_ino));
+               uh->journal_id = stamp;
+               flush_dcache_page(page);
+               set_page_dirty(page);
+               ntfs_unmap_page(page);
+               /* Set the flag so we do not have to do it again on remount. */
+               NVolSetUsnJrnlStamped(vol);
+       }
+       ntfs_debug("Done.");
+       return TRUE;
+}
+
+#endif /* NTFS_RW */