Patent · US Expired

Memory management and protection system for virtual memory in computer system

US5627987A · kind A · utility

46Cited by
14References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 23, 1993
Grant dateMay 6, 1997
Priority date
Expiry dateFeb 23, 2013

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F2212/656
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A memory management and protection system for realizing a high speed execution and a proper and flexible memory access control for multiple programs sharing an identical logical address space. In the system, the memory access is permitted according to a segment identifier identifying a segment in the logical address space, and a memory protection information for a region in each segment including a target right permission to indicate assigned rights to make a memory access from the region to each of the segments, and an execution permission to indicate a type of the memory access permitted by the right permission. Alternatively, a memory access can be permitted by using an access control list to be attached to each address table entry, which stores a plurality of program numbers identifying programs which are permitted to make accesses to the logical address stored in each address table entry, among which one that matches with the current program number is to be searched. Also, it is preferable to allocate a plurality of programs within a limit of available memory protection capacity to an identical logical address space, without any overlap between adjacently allocated address reg…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.