Access control mechanism controlling access to and logical purging of access register translation lookaside buffer (ALB) in a computer system
US5574936A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 25, 1995 |
| Grant date | Nov 12, 1996 |
| Priority date | — |
| Expiry date | Jan 25, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F12/1036
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An access control apparatus in a computer system for controlling access to an ALB. A host ALBID register and a guest ALBID register is provided for storing a host and a guest ALB identifier (ALBID) and a host and a guest ALBID validity indicator. Control State Software generates and stores the host and guest ALBIDs in the host and guest ALBID registers and marks valid the host and guest ALBID validity indicator whenever a host or guest mode is initiated or a logical purge is requested by a logical processor and for storing the host or guest ALBID stored in the host and guest ALBID registers when an ALB entry is made in the ALB by a logical processor. Access to an ALB entry by a logical processor is permitted when the logical processor is in the host mode if the ALBID in the ALB entry matches the host ALBID stored and the valid indicator is marked valid in the host ALBID register and when the logical processor is in the guest mode if the ALBID in the ALB entry matches the guest ALBID stored and the valid indicator is marked valid in the guest ALBID register. A host logical purge is accomplished by marking invalid the host and guest validity indicators in the host and guest ALBID reg…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.