commit
24a5d59f3477bcff4c069ff4d0ca9a3e037d0235 upstream.
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 <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
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)