Creating a single subspace

The following is a simple illustration of how a server program can manage a single subspace.

Table 1. How a server program manages single subspaces.
Server program	Functions
STORAGE OBTAIN	Obtain storage in application server address space Receive storage to be used for subspaces
IARSUBSP IDENTIFY	Make storage ranges eligible for subspaces Specify storage that was previously obtained
IARSUBSP CREATE	Create the subspace Receive STOKEN
ALESERV ADD	Add the subspace to the DU-AL, specifying STOKEN Receive ALET
IARSUBSP ASSIGN	Assign the range of storage that a program running in the subspace can reference Specify STOKEN, storage portion
BSG	Branch to subspace Specify ALET Run application program in subspace
BSG	Branch back to full address space addressability Specify ALET 0
IARSUBSP UNASSIGN	Disassociate the range of storage from the subspace Specify STOKEN, storage range
ALESERV DELETE	Remove entry from the access list Specify ALET
IARSUBSP DELETE	Delete the subspace Specify STOKEN
IARSUBSP UNIDENTIFY	Make storage ranges ineligible for subspace usage Specify storage that was previously specified on IARSUBSP IDENTIFY
STORAGE RELEASE	Release storage in application server address space Specify storage