1. A method for reading data from a non-volatile mass storage device, comprising: operating a non-volatile mass storage device in a direct data file storage (DFS) mode where a host system sends a file identifier and an offset address to a direct data file interface of the non-volatile mass storage device and wherein the non-volatile mass storage device generates a file directory and a file index table; when the non-volatile mass storage device detects that it is inserted into a legacy host system, operating the non-volatile mass storage device in a logical configuration mode by performing a logical configuration for the non-volatile mass storage device, wherein the logical configuration is performed by a memory controller of the non-volatile mass storage device and during the logical configuration a logical index is created by the memory controller, where the logical index includes an entry for each file that is identified in the file directory, which is maintained by the memory controller; and each entry specifies an address for a file identified in the file directory within a virtual logical address space for the non-volatile mass storage device maintained by the memory controller, and a corresponding entry location in the file directory; and operating the non-volatile mass storage device such that data identified by the virtual logical address is read by the host system.