Methods and apparatus for backup and restore of thin provisioning volume

Methods and apparatuses for backing up virtual volumes effectively by eliminating transfer and preservation of parts of virtual volumes, which contain no data. By representing virtual volumes as virtual files in a virtual file system, it is thereby possible to avoid needlessly backing up empty data space in the virtual volume. In one implementation, a storage system includes multiple virtual volumes and a virtual file system as well as a storage system control module. Each virtual volume in the multiple virtual volumes is represented as a virtual file within the virtual file system with each virtual file representing data actually stored within the virtual volume; and the storage system control module facilitates backing up a selected virtual volume, the operations involving accessing the virtual file system on the storage system; and reading the virtual file corresponding to the selected virtual volume.