Memory area management method

A memory area management method for data management of a storage device by a logical data management layer including an exclusive control manager, the method comprising the steps of:

• obtaining an exclusive write control over a data management layer from said exclusive control manager;
• obtaining a page management structure for the data management layer provided with said exclusive write control;
• obtaining all memory areas managed by said page management structure and creating a list of memory areas that are obtainable;
• determining whether one or more memory areas are not obtainable based on said list;
• and
• if it has been determined that one or more memory areas are not obtainable, reconfiguring said page management structure based on said list,
• wherein the memory size of said data management layer is changed when said data management layer is mounted at the first access to said data management layer and when the memory size of said storage device has been changed.

A memory area management method for data management of a storage device by a logical data management layer including an exclusive control manager, the method comprising the steps of:

• obtaining an exclusive write control over the last memory area from said exclusive control manager;
• obtaining a page management structure for the memory area provided with said exclusive control;
• obtaining all memory areas managed by said page management structure and creating a list of memory areas that are actually obtainable;
• determining whether one of more memory areas are not obtainable based on said list;
• if it has been determined that one or more memory areas are not obtainable, reconfiguring the page management structure based on said list;
• if said page management structure reconfigured does not include any available memory area, obtaining an exclusive write control over the data management layer from said exclusive control manager;
• obtaining a segment management structure for the data management layer provided with-said exclusive control;
• and
• obtaining an exclusive write control over the last memory area from said exclusive control manager and removing the segment provided with the exclusive write control from said segment management structure,
• wherein memory size change on said data management layer is processed upon detection of a change in the capacity of said storage device.

A computer comprising:

• an interface to be coupled to a storage device including a group of plurality of memory areas each of which stores data used by an application;
• and,
• a main board coupled to the interface;
• wherein:
• the main board is configured to include a processor for executing an application and a memory coupled to the processor,
• if data in a first memory area among the memory areas is not used by the application, the processor specifies a memory area among the group of the memory areas,
• copies, to the first memory area, data in the specified memory area, erases data which has been stored in the specified memory area,
• sets the specified memory area to a second memory area as memory area where data has been erased,
• compares between number of a group of second memory areas and predetermined number of memory areas,
• allocates a new memory area from the group of the second memory areas to the application, the new memory area is located other than predetermined number of second memory areas from tail of the group of the second areas, if the number of a group of second memory areas are more than predetermined number of memory areas, and,
• sends, to the application, an instruction indicating that if the number of a group of second memory areas are less than predetermined number of memory areas.