Method to control i/o accesses in a multi-tasking virtual memory virtual machine type data processing system

Abstract From the Canadian patent

A method for accessing information in a page segmented virtual memory data processing system in which virtual machines running UNIX type operating systems are concurrently established and in, which a memory manager controls the transfer of information between primary and secondary storage devices in response to the occurrence of page faults. The method establishes a plurality of data structures in a dynamic manner in response to a Supervisor call to "map" a file. The mapping process assigns a new segment of virtual memory to the mapped file and correlates, in one data structure the virtual, address of each page of data in the new segment to a disk file address where that page is actually …