Various methods and systems can be used to provide standard file system access to data that is originally accessed only by a proprietary interface. One such method involves querying an application (e.g., a database management system) for information identifying a location of each of several data objects within several volumes. The application provides a proprietary interface to the data objects stored on the volumes. The method then creates metadata, which associates each of several files within a new file system with the location of a respective one of the data objects within the volumes. The metadata can be created by an in-place conversion module implemented on a computing device. The method then provides the application with access to the files within the new file system, subsequent to creating the metadata.