US Patent 8073816 Volume format conversion

Data storage volumes, such as a file system on a storage system, may utilize a particular operating system format. Converting a volume to a different format may be desirable at times. However, this can be time consuming and resource intensive if data needs to be copied. Accordingly, substantially copying-free, in-place conversion of a data-storage volume from a first format to a second format is provided herein. In one embodiment, it is determined whether the volume can be converted, for example, by comparing compatibility of features between the first and second formats. A desired feature list is retrieved and respective features are checked for compatibility. Access to the volume is blocked during the conversion, and the volume is converted if the features are found to be compatible. If the conversion is successful, post conversion operations are performed, including unblocking the volume and notifying clients that the volume is available for access.