SUBBK | Back to Index page

| Prolog Control Block Contents SUBBK DSECT Storage Layout Cross Reference (Contains links to field and bit definitions) |
Programming Interface Information: This information is NOT intended to be used as Programming Interfaces of z/VM.

SUBBK Prolog | Top of page

     NAME       : DMSSUBBK
     DESCRIPTION: Subpool descriptor block
     DSECT      : SUBBK
     FUNCTION   : Mapping macro which maps information
                  about storage management subpools. CMS defines
                  a SUBBK for each subpool it creates.

SUBBK Control Block Content | Top of page

     SUBBK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      SUBBK          Subpool descriptor block
    0000    0 Signed       4 SUBFORWD       Forward pointer for Private
                                            SUBBKs
    0004    4 Signed       4 SUBBACKW       Backward pointer for Private
                                            SUBBKs
    0008    8 Signed       4 SUBSHFOR       Forward pointer for Shared SUBBKs
    000C   12 Signed       4 SUBSHBAC       Backward pointer for Shared
                                            SUBBKs
    0010   16 Signed       4 SUBPARTP       Anchor for chain of paritally
                                            allocated pages
    0014   20 Signed       4 SUBFULLP       Anchor for chain of fully
                                            allocated pages
    0018   24 Character    8 SUBPNAME       Name of the subpool
    0020   32 Bitstring    1 SUBPFLAG       Flags to define the described
                                            page
              1... ....      SUBLASTP       X'80' Last partial page added is
                                            still active
              .1.. ....      SUBPSYST       X'40' System subpool, survives
                                            ABEND
              .... .1..      SUBPNEW        X'04' Most recent created subpool
                                            on this SVC level
              .... ..11      SUBPGLOB       X'03' The subpool is GLOBAL
              .... ..1.      SUBPSHAR       X'02' The subpool is SHARED
              .... ...1      SUBPPRIV       X'01' The subpool is PRIVATE
          IF YOU ARE MOVING THESE BITS PLEASE NOTE
          NOTES      :  The following bits have a corresponding bit in the SPPL
                 byte of the SPPL. The bits are in the same locations:
            SPPLFG1       SUBPFLAG    Bit Position (in both)
            -------       --------    ----------------------
                 SPPLSYS       SUBPSYST        X'40'
                 SPPLGLO       SUBPGLOB        X'03'
                 SPPLSHA       SUBPSHAR        X'02'
                 SPPLPRI       SUBPPRIV        X'01'
    0021   33 Bitstring    1 SUBPKEY        Storage key for the described
                                            subpool
    0022   34 Signed       2 SUBLASTO       Size of last piece causing new
                                            part pg
    0024   36 Signed       4 SUBTAILP       Tail pointer-partially allocated
                                            chain
    0028   40 Signed       4 SUBFPTHD       Head pointer for full-partial
                                            chain
    002C   44 Signed       4 SUBFPTTL       Tail pointer for full-partial
                                            chain
              00000030       SUBSIZEB       *-SUBBK Size of a SUBBK in bytes
              00000006       SUBSIZED       (SUBSIZEB+7)/8 Size of a SUBBK in
                                            D-words

SUBBK Storage Layout | Top of page

    *** SUBBK - Subpool descriptor block
    *
    *     +---------------------------+---------------------------+
    *   0 |         SUBFORWD          |         SUBBACKW          |
    *     +---------------------------+---------------------------+
    *   8 |         SUBSHFOR          |         SUBSHBAC          |
    *     +---------------------------+---------------------------+
    *  10 |         SUBPARTP          |         SUBFULLP          |
    *     +---------------------------+---------------------------+
    *  18 |                       SUBPNAME                        |
    *     +------+------+-------------+---------------------------+
    *  20 |:PFLAG|:PKEY |  SUBLASTO   |         SUBTAILP          |
    *     +------+------+-------------+---------------------------+
    *  28 |         SUBFPTHD          |         SUBFPTTL          |
    *     +---------------------------+---------------------------+
    *  30
    *
    *** SUBBK - Subpool descriptor block

SUBBK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    SUBBACKW       0004
    SUBFORWD       0000
    SUBFPTHD       0028
    SUBFPTTL       002C
    SUBFULLP       0014
    SUBLASTO       0022
    SUBLASTP       0020 80
    SUBPARTP       0010
    SUBPFLAG       0020
    SUBPGLOB       0020 03
    SUBPKEY        0021
    SUBPNAME       0018
    SUBPNEW        0020 04
    SUBPPRIV       0020 01
    SUBPSHAR       0020 02
    SUBPSYST       0020 40
    SUBSHBAC       000C
    SUBSHFOR       0008
    SUBSIZEB       002C 00000030
    SUBSIZED       002C 00000006
    SUBTAILP       0024

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:36:14 EDT.
Copyright IBM Corporation, 1990, 2020