Information Processing Apparatus and Driver

Abstract

According to one embodiment, an information processing apparatus includes a memory that comprises a buffer area, a first external storage, a second external storage and a driver. The driver is configured to control the first and second external storages in units of predetermined blocks. The driver comprises a cache reservation module configured to (i) reserve a cache area in the memory, the cache area being logically between the buffer area and the first external storage and between the buffer area and the second external storage and (ii) manage the cache area. The cache area operates as a primary cache for the second external storage and a cache for the first external storage. Part or the entire first external storage is used as a secondary cache for the second external storage. The buffer area is used to transfer data between the driver and a host system that requests data reads/writes.

What is claimed is: 
     
         1 . An information processing apparatus comprising:
 a memory comprising a buffer area;   a first external storage separate from the memory;   a second external storage separate from the memory; and   a driver configured to control the first and second external storages in units of predetermined blocks,   wherein the driver comprises a cache reservation module configured to reserve a cache area in the memory, the cache area being logically between the buffer area and the first external storage and between the buffer area and the second external storage, and the cache reservation module is configured to manage the cache area in units of the predetermined blocks, using the cache area, secured on the memory by the cache reservation module, as a primary cache for the second external storage and a cache for the first external storage, and using part or the entire first external storage as a secondary cache for the second external storage, the buffer area being reserved in order to transfer data between the driver and a host system that requests for data writing and data reading.   
     
     
         2 . A driver stored in a non-transitory computer readable medium which operates in an information processing apparatus comprising a memory comprising a buffer area which is reserved in order to transfer data between the driver and a host system that requests for data writing and data reading, a first external storage and a second external storage, the driver being configured to control the first and second external storages in units of predetermined blocks, the driver comprising:
 a cache reservation module configured to reserve a cache area in the memory, the cache area being logically between the buffer area and the first external storage and between the buffer area and the second external storage, the driver being configured to manage the cache area in units of the predetermined blocks using the cache area, secured on the memory by the cache reservation module, as a primary cache for the second external storage and as a cache for the first external storage, and using part or the entire first external storage as a secondary cache for the second external storage.