[PATCH] dm: block size bug with 64 bit devs

With 32 bit sector_t the block device size _in bytes_ is also cut to
32 bit in __set_size when the block device is mount (a filesystem
mounted). The argument should be cast to loff_t before expanding the
sector count to a byte count and calling i_size_write.

[Christophe Saout]

drivers/md/dm.c

@@ -674,7 +674,7 @@ static void __set_size(struct gendisk *disk, sector_t size)
 	bdev = bdget_disk(disk, 0);
 	if (bdev) {
 		down(&bdev->bd_inode->i_sem);
-		i_size_write(bdev->bd_inode, size << SECTOR_SHIFT);
+		i_size_write(bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
 		up(&bdev->bd_inode->i_sem);
 		bdput(bdev);
 	}