System for providing application programs with direct addressability into a shared dataspace

Claim 1

In an operating system executing on a computer, a method of sharing dataspaces among a plurality of applications executing in the computer, the method comprising steps of: (a) initializing a Dataspace Services (DataServ) Subsystem in the computer, the initializing step further comprising the steps of obtaining storage for a DataServ Router Table (DSRT) in an Extended Common Storage Area (ECSA) provided by the operating system, anchoring the DSRT by storing a pointer thereto in a SubSystem Communications Vector Table (SSCVT) residing in the ESCA, wherein the SSCVT is accessible through the operating system; (b) executing a DataServ task in the computer, the executing step further comprising the steps of obtaining storage for a DataServ Vector Table (DSVT) in the ECSA, storing a job name for the DataServ task and a pointer to the DSVT in the DSRT, creating one or more dataspaces by invoking a utility of the operating system which returns STOKENs identifying the created dataspaces, obtaining storage for Dataspace Information Elements (DSIEs) in the ECSA, storing a pointer to the DSIEs in the DSVT, and storing the STOKENs in the DSIEs associated with the created dataspaces; (c) executing an application in the computer, the executing step further comprising the steps of accessing the SSCVT via the operating system to retrieve the pointer to the DSRT, searching the DSRT for the job name of a particular DataServ task, accessing the DSRT to retrieve the pointer to the DSVT associated with the job name and thus the particular DataServ task, accessing the DSVT to retrieve the pointer to the DSIEs, searching the DSIEs for a name of a particular dataspace, accessing the DSIE to retrieve the STOKEN associated with the particular dataspace, and using the STOKEN to provide direct addressability to the dataspace; and (d) repeating the executing step (c) for a plurality of applications.

Claim 17

A method of sharing data residing in a data-only address space among a plurality of applications executing in a computer, the method comprising the steps of: (a) initializing the data-only address space, the initializing step further comprising the steps of allocating the data-only address space in a memory location of the computer, loading data therein, allocating one or more control blocks in globally accessible memory locations of the computer, storing information in the control blocks that identifies the data-only address space, and establishing an anchor at a fixed location in the globally accessible memory that points to the control blocks; (b) executing an application, the executing step further comprising accessing the anchor at the fixed location, determining the globally accessible memory locations of the control blocks, accessing the control blocks at the determined locations, retrieving the information in the control blocks, resolving the information stored in the control blocks into an address for the memory location of the data-only address space, wherein the resolving step further comprises: (1) invoking a ALESERV macro-instruction to add an STOKEN identifying the dataspace to an access list attached to the application, wherein the ALESERV macro-instruction returns an access list index for the STOKEN, (2) switching into an access register (AR) address space control (ASC) mode so that the application can directly address the dataspace, and (3) loading the dataspace into an access register so the contents of both a general purpose register and the access register are resolved to a specific location in the dataspace, and accessing the data in the data-only address spaces using the address; and (c) repeating the executing step (b) for a plurality of applications.

Claim 18

A method of sharing data residing in a data-only address space among a plurality of applications executing in a computer, the method comprising the steps of: (a) initializing the data-only address space, the initializing step further comprising the steps of allocating the data-only address space in a memory location of the computer, loading data therein, allocating one or more control blocks in globally accessible memory locations of the computer, storing information in the control blocks that identifies the data-only address space, and establishing an anchor at a fixed location in the globally accessible memory that points to the control blocks; (b) executing an application, the executing step further comprising accessing the anchor at the fixed location, determining the globally accessible memory locations of the control blocks, accessing the control blocks at the determined locations, retrieving the information in the control blocks, resolving the information stored in the control blocks into an address for the memory location of the data-only address space, wherein the resolving step further comprises: (1) invoking a ALESERV macro-instruction to add an STOKEN identifying the dataspace to an access list attached to the application, wherein the ALESERV macro-instruction returns an access list index for the STOKEN, (2) switching into an access register (AR) address space control (ASC) mode so that the application can directly address the dataspace, and (3) loading the dataspace into an access register so the contents of both a general purpose register and the access register are resolved to a specific location in the dataspace, and accessing the data in the data-only address spaces using the address; and (c) repeating the executing step (b) for a plurality of applications.

Claim 19

An apparatus for sharing a dataspace stored in a memory of a computer among a plurality of applications executing in the computer, comprising: (a) a dataspace services task, executing in the computer, for establishing a dataspace in the memory of the computer; (b) one or more control blocks, stored in globally accessible locations in the memory of the computer and anchored by a pointer in a fixed location, for storing information therein identifying the dataspace services task and the dataspace established thereby; and (c) an application interface, linked to each of a plurality of applications executing in the computer, comprising means for resolving the information stored in the control blocks into an address for the dataspace, wherein the means for resolving further comprises: (1) means for invoking a ALESERV macro-instruction to add an STOKEN identifying the dataspace to an access list attached to the application, wherein the ALESERV macro-instruction returns an access list index for the STOKEN, (2) means for switching into an access register (AR) address space control (ASC) mode so that the application can directly address the dataspace, and (3) means for loading the access list index of the STOKEN identifying the dataspace into an access register so the contents of both a general purpose register and the access register are resolved to a specific location in the dataspace, and means for transferring data between the dataspace and one of the applications.

Claim 20

An apparatus for sharing a dataspace stored in a memory of a computer among a plurality of applications executing in the computer, comprising: (a) a dataspace services task, executing in the computer, for establishing a dataspace in the memory of the computer; (b) one or more control blocks, stored in globally accessible locations in the memory of the computer and anchored by a pointer in a fixed location, for storing information therein identifying the dataspace services task and the dataspace established thereby; and (c) an application interface, linked to each of a plurality of applications executing in the computer, comprising means for resolving the information stored in the control blocks into an address for the dataspace, wherein the means for resolving further comprises: (1) means for invoking a ALESERV macro-instruction to add an STOKEN identifying the dataspace to an access list attached to the application, wherein the ALESERV macro-instruction returns an access list index for the STOKEN, (2) means for switching into an access register (AR) address space control (ASC) mode so that the application can directly address the dataspace, and (3) means for loading the access list index of the STOKEN identifying the dataspace into an access register so the contents of both a general purpose register and the access register are resolved to a specific location in the dataspace, and means for transferring data between the dataspace and one of the applications.