$SCABK | Back to Index page

| Prolog Control Block Contents $SCABK 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.

$SCABK Prolog | Top of page

     NAME       : LGRSCABK
     DESCRIPTION: Relocation mapping for HCPSCABK
     DSECT      : $SCABK
     FUNCTION   : LGRSCABK describes those fields of the SCABK 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 HCPSCABK 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.

$SCABK Control Block Content | Top of page

     $SCABK DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      $SCABK         Relocation mapping for HCPSCABK
              00000001       $SCA_VER       1 Mapping version number
    0000    0 Signed       2 $SCA_HDRL      Header length (in bytes)
    0002    2 Signed       2 $SCA_BITL      Length of mapped bits (in bytes)
    0004    4 Signed       2 $SCA_DATL      Length of mapped data (in bytes)
    0006    6 Signed       2 *              Reserved for future use
              00000008       $SCA_HDLN      *-$SCABK Length of header (bytes)
          Bit map: Contains the SCABK flags that are subject to
                   relocation. These bits are defined sequentially,
                   regardless of how they are defined in HCPSCABK.
                   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.
    0008    8 Signed       2 $SCA_BITS (0)  Bit map area
              00000000       $SCA_BLEN      *-$SCA_BITS Length of bit map
                                            area
          Data:    Contains all HCPSCABK 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.
                   together with new flag bytes as required.
    0008    8 Bitstring    1 $SCA_DATA (0)  Start of data map
    0008    8 Bitstring    8 $SCAMCN        Mask of valid virtual CPU addrs
    0010   16 Bitstring    2 $SCAXCOF       Offset to SCAXCALL data
              00000012       $SCA_LEN       *-$SCABK Length of fixed area (is
                                            also the offset to $SCAXC)
              00000003       $SCA_SZ        ($SCA_LEN+7)/8 Size of fixed area
                                            (DW)
          Mapping for SCAXCALL data.
    0012   18 Bitstring    1 $SCAXC (0)     This data appears VMDCPUCT+1
                                            times
    0012   18 Bitstring    4 $SCAXCPUA      vCPU address
    0016   22 Bitstring    1 $SCAXCALL      SCAXCALL value for vCPU
              00000005       $SCAXCLEN      *-$SCAXC Length of a single entry

$SCABK Storage Layout | Top of page

    *** $SCABK - Relocation mapping for HCPSCABK
    *
    *     +-------------+-------------+-------------+-------------+
    *   0 | $SCA_HDRL   | $SCA_BITL   | $SCA_DATL   |/////////////|
    *     +-------------+-------------+-------------+-------------+
    *   8 |                       $SCAMCN                         |
    *     +-------------+---------------------------+------+------+
    *  10 |  $SCAXCOF   |        $SCAXCPUA          |(016) | 17
    *     +-------------+---------------------------+------+
    *
    *** $SCABK - Relocation mapping for HCPSCABK

$SCABK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    $SCA_BITL      0002
    $SCA_BITS      0008
    $SCA_BLEN      0008 00000000
    $SCA_DATA      0008
    $SCA_DATL      0004
    $SCA_HDLN      0006 00000008
    $SCA_HDRL      0000
    $SCA_LEN       0010 00000012
    $SCA_SZ        0010 00000003
    $SCA_VER       0000 00000001
    $SCAMCN        0008
    $SCAXC         0012
    $SCAXCALL      0016
    $SCAXCLEN      0016 00000005
    $SCAXCOF       0010
    $SCAXCPUA      0012

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:32:10 EDT.
Copyright IBM Corporation, 1990, 2020