Programming Interface Information: This information is NOT intended to be
used as Programming Interfaces of z/VM.

XSUBK

Prolog
Control Block Contents
XSUBK DSECT
Storage Layout
Cross Reference

XSUBK Prolog

 NAME       : HCPXSUBK
 DESCRIPTION: Expanded Storage Usability Map
 DSECT      : XSUBK
 FUNCTION   : This map is used to keep track of the allocation
              of Expanded Storage. Each map corresponds to one
              increment of XSTORE and can therefore represent
              up to 64Meg of expanded storage.
 LOCATED BY : XDRUMAPT located in the HCPXDRBK.
 CREATED BY : HCPESCDI during initialization processing.
 DELETED BY : HCPESCDI if no expanded storage is configured
              to the system.

 

XSUBK Control Block Content

XSUBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      XSUBK          Expanded Storage Usability Map
     The following are bit maps that represents the allocation of one
     increment of Expanded Storage (up to 64 megabytes). Each bit position
     represents the allocation state of a block of XSTORE.
0000    0 Bitstring    1 XSUALMAP (2048)
                                        XSTORE availability map. When a
                                        bit's value is "1" then the
                                        corresponding block is allocated.
0800 2048 Bitstring    1 XSUERMAP (2048)
                                        XSTORE error map. When a bit's
                                        value is "1" then the
                                        corresponding block is in error.

 

XSUBK Storage Layout

          
*** XSUBK - Expanded Storage Usability Map
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       XSUALMAP                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 800 |                                                       |
*     =                       XSUERMAP                        =
*     |                                                       |
*     +-------------------------------------------------------+
*1000
*
*** XSUBK - Expanded Storage Usability Map

 

XSUBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
XSUALMAP       0000
XSUERMAP       0800

This information is based on z/VM V3R1.0.
Last updated on 30 Mar 2001 at 09:18:23 EDT.
Copyright IBM Corporation, 1990, 2001