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

#### MSABK

Prolog

Control Block Contents
MSABK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### MSABK Prolog

     NAME       : HCPMSABK
     DESCRIPTION: Map of Slot Allocation
     DSECT      : MSABK
     FUNCTION   : Slot bit map for page or spool EXTBK
     LOCATED BY : EXTSTRCT
     CREATED BY : - HCPPGU when extent is selected for
                  allocation.
                  - HCPPGT when reallocating spool slots
                  during IPL.
                  - HCPPGC when extent selected to use as
                  Dump space.
     DELETED BY : HCPRDD when a CP-owned device is detached
                  from the system.
     REFERENCES :
                  HCPEXTBK - Extent block
     SERIALIZED : Page or Spool allocation lock
     NOTES      : MSABK represents a maximum of 8000 slots.

#### MSABK Control Block Content

#### MSABK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      MSABK          Map of Slot Allocation
    0000    0 Bitstring 1000 MSASLOTS       Slot bit map...Each bit
                                            represents a slot in the EXTBK.
                                            If bit = 1, slot is in use. If
                                            bit = 0, slot is not in use.
              0000007D       MSASIZE        (*-MSABK+7)/8
              00001F40       MSAMAXSL       8000 Max number of slots per
                                            MSABK
         * end ASM version

#### MSABK Storage Layout

    *** MSABK - Map of Slot Allocation
    *
    *     +-------------------------------------------------------+
    *   0 |                                                       |
    *     =                       MSASLOTS                        =
    *     |                                                       |
    *     +-------------------------------------------------------+
    * 3E8
    *
    *** MSABK - Map of Slot Allocation

#### MSABK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    MSAMAXSL       0000 00001F40
    MSASIZE        0000 0000007D
    MSASLOTS       0000

This information is based on z/VM V6R1.0. Last updated on 18 Feb 2010 at 08:51:06 EDT.
Copyright IBM Corporation, 1990, 2008