Patent ID: 8533429
Filing Date: 2013-09-10
Classification: G06F

Abstract:
1. A memory access control device comprising: a storage unit for storing data and a page table that indicates, for each of a plurality of pages, correspondence between a virtual page number and a physical page number, the virtual page number being part of a virtual address and indicating a page, and the physical page number being part of a physical address and indicating the page; a conversion unit that includes a buffer for storing, for each page in a subset of the plurality of pages, the virtual page number and the physical page number in correspondence, and a conversion processing unit configured to convert a virtual address included in an access request into a physical address corresponding to the virtual address included in the access request in accordance with content stored in the buffer; and a control unit configured (i) to transmit the virtual address included in the access request to the conversion processing unit for conversion into the physical address corresponding to the virtual address included in the access request and (ii) to obtain data from the storage unit in accordance with the physical address corresponding to the virtual address included in the access request as yielded by the conversion processing unit, wherein when the virtual page number of the virtual address included in the access request is not stored in the buffer, the conversion processing unit overwrites, in the buffer, (i) the virtual page number and the physical page number of a page from among the subset of the plurality of pages, the page from among the subset of the plurality of pages having a completed conversion count, indicating a number of times the virtual address of the page from among the subset of the plurality of pages has been converted to the physical address of the page from among the subset of the plurality of pages, which has reached a planned conversion count, with (ii) the virtual page number of the virtual address included in the access request and the physical page number corresponding, in the storage unit, to the virtual page number of the virtual address included in the access request.