v4.19.13 snapshot.
diff --git a/fs/udf/lowlevel.c b/fs/udf/lowlevel.c
new file mode 100644
index 0000000..5c7ec12
--- /dev/null
+++ b/fs/udf/lowlevel.c
@@ -0,0 +1,67 @@
+/*
+ * lowlevel.c
+ *
+ * PURPOSE
+ * Low Level Device Routines for the UDF filesystem
+ *
+ * COPYRIGHT
+ * This file is distributed under the terms of the GNU General Public
+ * License (GPL). Copies of the GPL can be obtained from:
+ * ftp://prep.ai.mit.edu/pub/gnu/GPL
+ * Each contributing author retains all rights to their own work.
+ *
+ * (C) 1999-2001 Ben Fennema
+ *
+ * HISTORY
+ *
+ * 03/26/99 blf Created.
+ */
+
+#include "udfdecl.h"
+
+#include <linux/blkdev.h>
+#include <linux/cdrom.h>
+#include <linux/uaccess.h>
+
+#include "udf_sb.h"
+
+unsigned int udf_get_last_session(struct super_block *sb)
+{
+ struct cdrom_multisession ms_info;
+ unsigned int vol_desc_start;
+ struct block_device *bdev = sb->s_bdev;
+ int i;
+
+ vol_desc_start = 0;
+ ms_info.addr_format = CDROM_LBA;
+ i = ioctl_by_bdev(bdev, CDROMMULTISESSION, (unsigned long)&ms_info);
+
+ if (i == 0) {
+ udf_debug("XA disk: %s, vol_desc_start=%d\n",
+ ms_info.xa_flag ? "yes" : "no", ms_info.addr.lba);
+ if (ms_info.xa_flag) /* necessary for a valid ms_info.addr */
+ vol_desc_start = ms_info.addr.lba;
+ } else {
+ udf_debug("CDROMMULTISESSION not supported: rc=%d\n", i);
+ }
+ return vol_desc_start;
+}
+
+unsigned long udf_get_last_block(struct super_block *sb)
+{
+ struct block_device *bdev = sb->s_bdev;
+ unsigned long lblock = 0;
+
+ /*
+ * ioctl failed or returned obviously bogus value?
+ * Try using the device size...
+ */
+ if (ioctl_by_bdev(bdev, CDROM_LAST_WRITTEN, (unsigned long) &lblock) ||
+ lblock == 0)
+ lblock = i_size_read(bdev->bd_inode) >> sb->s_blocksize_bits;
+
+ if (lblock)
+ return lblock - 1;
+ else
+ return 0;
+}