From 24a5d59f3477bcff4c069ff4d0ca9a3e037d0235 Mon Sep 17 00:00:00 2001 From: Jan Kara Date: Thu, 18 Jun 2009 12:33:16 +0200 Subject: [PATCH] udf: Use device size when drive reported bogus number of written blocks Some drives report 0 as the number of written blocks when there are some blocks recorded. Use device size in such case so that we can automagically mount such media. Signed-off-by: Jan Kara --- fs/udf/lowlevel.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/fs/udf/lowlevel.c b/fs/udf/lowlevel.c index 703843f30ffd..1b88fd5df05d 100644 --- a/fs/udf/lowlevel.c +++ b/fs/udf/lowlevel.c @@ -56,7 +56,12 @@ unsigned long udf_get_last_block(struct super_block *sb) struct block_device *bdev = sb->s_bdev; unsigned long lblock = 0; - if (ioctl_by_bdev(bdev, CDROM_LAST_WRITTEN, (unsigned long) &lblock)) + /* + * 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 = bdev->bd_inode->i_size >> sb->s_blocksize_bits; if (lblock)