In order to manage the various types of attribute information within the
storage-device system, the storage-device system includes the following
databases within a file-access controlling memory: a database for
managing index information for managing contents of the files, and an
index retrieval program, a database for managing the attribute
information on the files, and a database for managing storage positions
of blocks configuring a file. When the storage-device system receives an
access request to a file, the utilization of these databases allows the
storage-device system to make the access to the access-target file.