$GSDBK | Back to Index page

| Prolog Control Block Contents $GSDBK 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.

$GSDBK Prolog | Top of page

     NAME       : LGRGSDBK
     DESCRIPTION: Relocation mapping for HCPGSDBK
     DSECT      : $GSDBK
     FUNCTION   : LGRGSDBK describes those fields of the GSDBK that
                  will be migrated to the destination system during
                  guest relocation.
     LOCATED BY : This is a mapping of the RDODATA area within the
                  RDOBK during guest relocation.
     RELOCATION CONSIDERATIONS : This control block is used during live guest
                  relocation.  It is used to relocate a control block
                  defined in a corresponding HCP COPY file.  Any
                  fields or bits defined in HCPGSDBK which are
                  required on the destination system must be defined
                  here, and code must be added to migrate the field
                  or bit during a relocation.

$GSDBK Control Block Content | Top of page

     $GSDBK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      $GSDBK         Relocation mapping for HCPGSDBK
              00000001       $GSD_VER       1 Mapping version number
    0000    0 Signed       2 $GSD_HDRL      Header length (in bytes)
    0002    2 Signed       2 $GSD_BITL      Length of mapped bits (in bytes)
    0004    4 Signed       4 *              Reserved for future use
              00000008       $GSD_HDLN      *-$GSDBK Length of header (bytes)
          NOTES      : This mapping is not intended to be comprehensive,
                since for the most part the GSDBKs that will be
                relocated contain simple character strings. The
                decoding routine(s) on the destination system will
                be aware of the context for the incoming GSDBK, and
                will therefore be able to set flags and other data
                as required.
          Bit map: Contains the GSDBK flags that are subject to
                   relocation. These bits are defined sequentially,
                   regardless of how they are defined in HCPGSDBK.
                   This yields a consistent mapping that ensures
                   compatibility when a guest is relocated between
                   systems at differing service levels.
                   Names in the comments column indicate the control
                   block byte which contains the flag. This name is
                   subject to change if the flag definition changes.
             ====> NEVER change bits which already exist here.
             ====> NEVER change the order of bits in this section.
             ====> ALWAYS add new bits at the end of this section,
                   together with new flag bytes as required.
          Special note concerning GSDFLAG:
                   GSDFLAG is relocated as a byte field, not as
                   individual bits. See the note in the prolog of
                   HCPGSDBK for more details.
    0008    8 Signed       2 $GSD_BITS (0)  Bit map area
    0008    8 Bitstring    1 $GSD0
              1... ....      $GSDCFMDG      X'80' $GSDCFMDG GSDTYPE
              .1.. ....      $GSDCFMCP      X'40' $GSDCFMCP GSDTYPE
              ..1. ....      $GSDCFMTR      X'20' $GSDCFMTR GSDTYPE
              ...1 ....      $GSD2305       X'10' $GSD2305 GSDTYPE
              .... 1...      $GSDREIPL      X'08' $GSDREIPL GSDTYPE
              .... .1..      $GSDIPLOG      X'04' $GSDIPLOG GSDTYPE
              .... ..1.      $GSDLOGIP      X'02' $GSDLOGIP GSDTYPE
              .... ...1      $GSDIRECT      X'01' $GSDIRECT GSDTYPE
              00000001       $GSD_BLEN      *-$GSD_BITS Length of bit map
                                            area
          Data:    Contains all HCPGSDBK data that is subject to
                   relocation, except for flag bits, which are
                   handled separately.
                   All fields are defined as XLnn to avoid alignment
                   warnings and to pack the data efficiently.
             ====> NEVER change fields which already exist here.
             ====> NEVER change the order of fields in this section.
             ====> ALWAYS add new fields at the end of this section.
    0009    9 Bitstring    1 $GSD_DATA (0)  Start of data map
    0009    9 Bitstring    4 $GSDNEXT       -> RDO offset to next $GSDBK
    000D   13 Bitstring    1 $GSDFLAG       GSDBK flags
    000E   14 Bitstring    2 $GSDSCAN       Byte disp of next fld in GSDDATA
    0010   16 Bitstring    2 $GSDDCNT       Length of GSDDATA in bytes
    0012   18 Bitstring    4 $GSDDATA       -> RDO offset to variable data
              00000016       $GSD_LEN       *-$GSDBK Total length, in bytes
              00000003       $GSD_SZ        ($GSD_LEN+7)/8 Size in
                                            doublewords

$GSDBK Storage Layout | Top of page

    *** $GSDBK - Relocation mapping for HCPGSDBK
    *
    *     +-------------+-------------+---------------------------+
    *   0 | $GSD_HDRL   | $GSD_BITL   |///////////////////////////|
    *     +------+------+-------------+------+------+-------------+
    *   8 |$GSD0 |         $GSDNEXT          |:DFLAG|  $GSDSCAN   |
    *     +------+------+--------------------+------+-------------+
    *  10 |  $GSDDCNT   |         $GSDDATA          | 16
    *     +-------------+---------------------------+
    *
    *** $GSDBK - Relocation mapping for HCPGSDBK

$GSDBK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    $GSD_BITL      0002
    $GSD_BITS      0008
    $GSD_BLEN      0008 00000001
    $GSD_DATA      0009
    $GSD_HDLN      0004 00000008
    $GSD_HDRL      0000
    $GSD_LEN       0012 00000016
    $GSD_SZ        0012 00000003
    $GSD_VER       0000 00000001
    $GSDCFMCP      0008 40
    $GSDCFMDG      0008 80
    $GSDCFMTR      0008 20
    $GSDDATA       0012
    $GSDDCNT       0010
    $GSDFLAG       000D
    $GSDIPLOG      0008 04
    $GSDIRECT      0008 01
    $GSDLOGIP      0008 02
    $GSDNEXT       0009
    $GSDREIPL      0008 08
    $GSDSCAN       000E
    $GSD0          0008
    $GSD2305       0008 10

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:32:04 EDT.
Copyright IBM Corporation, 1990, 2020