$MSTBK Back to Index page
Control Block Contents 
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.

  $MSTBK Prolog Top of page
 DESCRIPTION: Relocation mapping for HCPMSTBK
 DSECT      : $MSTBK
 FUNCTION   : LGRMSTBK describes those fields of the MSTBK 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 HCPMSTBK 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.
  $MSTBK Control Block Content Top of page

 $MSTBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure $MSTBK Relocation mapping for HCPMSTBK 00000001 $MST_VER 1 Mapping version number 0000 0 Signed 2 $MST_HDRL Header length (in bytes) 0002 2 Signed 2 $MST_BITL Length of mapped bits (in bytes) 0004 4 Signed 4 * Reserved for future use 00000008 $MST_HDLN *-$MSTBK Length of header (bytes) NOTES : This mapping is not intended to be comprehensive, since for the most part the MSTBKs 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 MSTBK, and will therefore be able to set flags and other data as required. Bit map: Contains the MSTBK flags that are subject to relocation. These bits are defined sequentially, regardless of how they are defined in HCPMSTBK. 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 $MST_BITS (0) Bit map area 00000000 $MST_BLEN *-$MST_BITS Length of bit map area Data: Contains all HCPMSTBK 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 $MST_DATA (0) Start of data map 0008 8 Bitstring 4 $MSTPTR -> RDO offset to next $MSTBK 000C 12 Bitstring 4 $MSTTLEN Message length 0010 16 Bitstring 6 $MSTCFRPM HCPCFRWT parameters 0016 22 Bitstring 4 $MSTTEXT -> RDO offset to message text block 0000001A $MST_LEN *-$MSTBK Fixed length, in bytes 00000004 $MST_SZ ($MST_LEN+7)/8 Size in doublewords
  $MSTBK Storage Layout Top of page
*** $MSTBK - Relocation mapping for HCPMSTBK
*     +-------------+-------------+---------------------------+
*   0 | $MST_HDRL   | $MST_BITL   |///////////////////////////|
*     +-------------+-------------+---------------------------+
*   8 |         $MSTPTR           |         $MSTTLEN          |
*     +---------------------------+-------------+-------------+
*  10 |               $MSTCFRPM                 | $MSTTEXT-   |
*     +-------------+---------------------------+-------------+
*  18 |   -(016)    | 1A
*     +-------------+
*** $MSTBK - Relocation mapping for HCPMSTBK
  $MSTBK Cross Reference Top of page
Symbol         Dspl Value
-------------- ---- -----
$MST_BITL      0002
$MST_BITS      0008
$MST_BLEN      0008 00000000
$MST_DATA      0008
$MST_HDLN      0004 00000008
$MST_HDRL      0000
$MST_LEN       0016 0000001A
$MST_SZ        0016 00000004
$MST_VER       0000 00000001
$MSTCFRPM      0010
$MSTPTR        0008
$MSTTEXT       0016
$MSTTLEN       000C
This information is based on z/VM 6.3.0 Last updated on 22 May 2013 at 13:56:36 EDT.
Copyright IBM Corporation, 1990, 2013