$IOCM Back to Index page
 
Prolog 
Control Block Contents 
   $IOCM 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.


  $IOCM Prolog Top of page
 
 NAME       : LGRIOCM
 DESCRIPTION: Relocation mapping for HCPIOCM
 DSECT      : $IOCM
 FUNCTION   : LGRIOCM describes those fields of the IOCM block
              that will be relocated to the destination system
              during guest relocation.
 LOCATED BY : This is a mapping of the RDODATA area within the
              RDOBK during guest relocation.
 CREATED BY : HCPRLFAF - AMSG/IOCM Formatter for LGR
 DELETED BY : HCPRLDRL - Release storage associated with an RDP
 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 HCPIOCM 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.
 
 
  $IOCM Control Block Content Top of page
 

 $IOCM DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure $IOCM Relocation mapping for HCPIOCM 00000001 $IOCM_VER 1 Mapping version number for this DSECT. Version is independent of the CP level and need only be changed when this DSECT is changed. The convention is to increment by 1. 0000 0 Signed 2 $IOCM_HDRL Header length (in bytes) 0002 2 Signed 2 $IOCM_BITL Length of mapped bits (in bytes) 0004 4 Signed 4 * Reserved for future use 00000008 $IOCM_HDLN *-$IOCM Length of header (bytes) Bit map: Contains the IOCM flags that are subject to relocation. These bits are defined sequentially, regardless of how they are defined in HCPIOCM. 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 $IOCM_BITS (0) Bit map area 0008 8 Bitstring 1 $IOCM0 1... .... $IOCMNBST X'80' $IOCMNBST IOCMFLAG 00000001 $IOCM_BLEN *-$IOCM_BITS Length of bit map area Data: Contains all HCPIOCM 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. 0009 9 Bitstring 1 $IOCM_DATA (0) Start of data map 0009 9 Bitstring 4 $IOCMNEXT Pointer to next IOCM block 000D 13 Bitstring 4 $IOCMBKID IDs storage area as an IOCM block 0011 17 Bitstring 2 $IOCMSCNT Sense data count 0013 19 Bitstring 32 $IOCMSNS Sense Data 0033 51 Bitstring 64 $IOCMIRB IRB data 00000073 $IOCM_LEN *-$IOCM Total length, in bytes 0000000F $IOCM_SZ ($IOCM_LEN+7)/8 Size in doublewords
 
 
  $IOCM Storage Layout Top of page
 
          
*** $IOCM - Relocation mapping for HCPIOCM
*
*     +-------------+-------------+---------------------------+
*   0 | $IOCM_HDRL  | $IOCM_BITL  |///////////////////////////|
*     +------+------+-------------+------+--------------------+
*   8 |$IOCM0|        $IOCMNEXT          |    $IOCMBKID-      |
*     +------+-------------+-------------+--------------------+
*  10 |-(00D)| $IOCMSCNT   |                                  |
*     +------+-------------+                                  |
*  18 |                                                       |
*     =                       $IOCMSNS                        =
*     |                    +----------------------------------+
*     |                    |                                  |
*     +--------------------+                                  |
*  38 |                                                       |
*     =                       $IOCMIRB                        =
*     |                    +----------------------------------+
*     |                    | 73
*     +--------------------+
*
*** $IOCM - Relocation mapping for HCPIOCM
 
 
  $IOCM Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
$IOCM_BITL     0002
$IOCM_BITS     0008
$IOCM_BLEN     0008 00000001
$IOCM_DATA     0009
$IOCM_HDLN     0004 00000008
$IOCM_HDRL     0000
$IOCM_LEN      0033 00000073
$IOCM_SZ       0033 0000000F
$IOCM_VER      0000 00000001
$IOCMBKID      000D
$IOCMIRB       0033
$IOCMNBST      0008 80
$IOCMNEXT      0009
$IOCMSCNT      0011
$IOCMSNS       0013
$IOCM0         0008
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:58:44 EDT.
Copyright IBM Corporation, 1990, 2022