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

#### ACSBK

Prolog

Control Block Contents
ACSBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### ACSBK Prolog

     Name       : HCPACSBK
     Description: CP Access Block
     DSECT      : ACSBK
     Function   : The ACSBK contains information about each
                  mini-disk accessed by CP.
     Located by : ACSPKBK.ACSPKPT(i)
     Created by : HCPZIOC2
     Deleted by : HCPZIOC2
                  - HCPZIOL2

#### ACSBK Control Block Content

#### ACSBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      ACSBK          CP Access Block
    0000    0 Address      4 ACSVDEV        A( VDEV )
    0004    4 Address      4 ACSRDEV        A( RDEV )
    0008    8 Character    8 ACSUID         Uid that owns the mini-disk
    0010   16 Bitstring    2 ACSVADDR       The mini-disk address
    0012   18 Signed       2 ACSBLKSZ       Size of blocks on the mini-disk
    0014   20 Signed       4 ACSBLKSF       Number of blocks formatted
    0018   24 Signed       4 ACSBLKSU       Number of blocks used
    001C   28 Address      4 ACSDVTAB       A( dev characteristics in HCPBST)
    0020   32 Address      4 ACSOFB         A( chain of OFBKs )
    0024   36 Address      4 ACSFSH         A( chain of FSHEADs )
    0028   40 Dbl-Word     8 ACSCDS         Label for Compare-Double-and-Swap
    0030   48 Signed       4 *              Reserved
    0034   52 Address      4 ACSCPEBK       A( CPEBK ), if any
    0038   56 Address      4 ACSVMDBK       A( VMDBK ) if mapped to virtual
                                            memory
    003C   60 Address      4 ACSBTMAP       A( bit map for virtual memory )
    0040   64 Character    6 ACSMDLAB       CMS Label of minidisk
    0046   70 Signed       2 *              Reserved for future IBM use
    0048   72 Signed       4 ACSSCYL        Real cylinder or block where
                                            mdisk starts
    004C   76 Signed       4 ACSECYL        Real cylinder or block where
                                            mdisk ends
              00000050       ACSBSIZB       (*-ACSBK) Size in bytes
              0000000A       ACSBSIZD       (*-ACSBK+7)/8 Size in d-words
    0028   40 Signed       2 *              Reserved
    002A   42 Bitstring    1 ACSMODE        Disk access mode (DDEVMODE)
    002B   43 Bitstring    1 ACSFLAG1       Flags
              .1.. ....      ACSRELSE       X'40' RELEASE issued for this
                                            minidisk
    002C   44 Address      4 ACSPOPEN       A( chain of pre-open DRBKs ) End
                                            of CDS area

#### ACSBK Storage Layout

    *** ACSBK - CP Access Block
    *
    *     +---------------------------+---------------------------+
    *   0 |         ACSVDEV           |         ACSRDEV           |
    *     +---------------------------+---------------------------+
    *   8 |                        ACSUID                         |
    *     +-------------+-------------+---------------------------+
    *  10 |  ACSVADDR   |  ACSBLKSZ   |         ACSBLKSF          |
    *     +-------------+-------------+---------------------------+
    *  18 |         ACSBLKSU          |         ACSDVTAB          |
    *     +---------------------------+---------------------------+
    *  20 |          ACSOFB           |          ACSFSH           |
    *     +---------------------------+---------------------------+
    *  28 |                        ACSCDS                         |
    *     +---------------------------+---------------------------+
    *  30 |///////////////////////////|         ACSCPEBK          |
    *     +---------------------------+---------------------------+
    *  38 |         ACSVMDBK          |         ACSBTMAP          |
    *     +---------------------------+-------------+-------------+
    *  40 |                ACSMDLAB                 |/////////////|
    *     +---------------------------+-------------+-------------+
    *  48 |         ACSSCYL           |         ACSECYL           |
    *     +---------------------------+---------------------------+
    *  50
    *
    *** ACSBK - CP Access Block

    *** Overlay for ACSCDS in ACSBK
    *
    *     +-------------+------+------+---------------------------+
    *  28 |/////////////|:MODE |:FLAG1|         ACSPOPEN          |
    *     +-------------+------+------+---------------------------+
    *  30
    *
    *** Overlay for ACSCDS in ACSBK

#### ACSBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    ACSBLKSF       0014
    ACSBLKSU       0018
    ACSBLKSZ       0012
    ACSBSIZB       004C 00000050
    ACSBSIZD       004C 0000000A
    ACSBTMAP       003C
    ACSCDS         0028
    ACSCPEBK       0034
    ACSDVTAB       001C
    ACSECYL        004C
    ACSFLAG1       002B
    ACSFSH         0024
    ACSMDLAB       0040
    ACSMODE        002A
    ACSOFB         0020
    ACSPOPEN       002C
    ACSRDEV        0004
    ACSRELSE       002B 40
    ACSSCYL        0048
    ACSUID         0008
    ACSVADDR       0010
    ACSVDEV        0000
    ACSVMDBK       0038

This information is based on z/VM V5R2.0. Last updated on 12 Apr 2006 at 16:38:55 EDT.
Copyright IBM Corporation, 1990, 2005