How to get columns from system tables or views like sys.database_files (SQL Server 2012)

Question

How can I write a query to return all columns of, for example, the sys.database_files table? I see many suggestions for using information_schema.columns for getting table names for user databases/tables, but i can't figure out how to do this for system tables.

I see that the sys.database_files is a view under the master table. I'm using SQL Server 2012.