CMPBK Back to Index page
 
Prolog 
Control Block Contents 
   CMPBK 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.


  CMPBK Prolog Top of page
 
 NAME       : HCPCMPBK
 DESCRIPTION: Component Id Block
 DSECT      : CMPBK
 FUNCTION   : The Component Id Block is used by customers and
              vendors as an anchor for whatever they want.
 LOCATED BY : XCTBK.XCTCMPAD
              CMPBK.CMPFWD
 CREATED BY : HCPZXCAC, called by HCPXSERV ALLOCATE
 DELETED BY : HCPZXCDC, called by HCPXSERV DEALLOCATE
 REFERENCES : None
 SERIALIZED : Changes to the chain of CMPBKs are typically done
              by HCPZXU under the exclusive lock XCTCMPLK.
              Searches of the chain of CMPBKs are typically done
              by HCPZXU under the shared lock XCTCMPLK.
              Changes to the contents of CMPBKs are typically done
              under the control of user code.  The CMPBKLK is
              provided for serialization to the contents of the CMPBK.
              Control over the CMPBKLK should be by means of the
              HCPXSERV macro operands LOCKEXCL, LOCKSHR, etc.
 RELOCATION CONSIDERATIONS : None
 
 
  CMPBK Control Block Content Top of page
 

 CMPBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure CMPBK Component Id Block The IBM fields should remain at the front of the block 0000 0 Dbl-Word 8 CMPBKLK (3) Lock word to serialize access to this CMPBK 0018 24 Address 4 CMPFWD Address of the next CMPBK 001C 28 Signed 1 CMPEXTNQ Size of extension at CMPEXTND in Number of Quad-words. The maximum allowed value for CMPEXTNQ is 240, which gives a maximum size for a CMPBK of x'60' + 240*16 = 3936 bytes which allows for a little growth up to 4072 bytes. 001D 29 Character 3 CMPID The component Id 0020 32 Character 8 * Reserved for IBM use 0028 40 Character 8 * Reserved for IBM use 0030 48 Character 8 * Reserved for IBM use 0038 56 Character 8 * Reserved for IBM use The user fields should remain at the end of the block 0040 64 Dbl-Word 8 CMPUSRD1 Reserved for non-IBM use 0048 72 Dbl-Word 8 CMPUSRD2 Reserved for non-IBM use 0050 80 Signed 4 CMPUSRF1 Reserved for non-IBM use 0054 84 Signed 4 CMPUSRF2 Reserved for non-IBM use 0058 88 Signed 2 CMPUSRH1 Reserved for non-IBM use 005A 90 Signed 2 CMPUSRH2 Reserved for non-IBM use 005C 92 Bitstring 1 CMPUSRX1 Reserved for non-IBM use 005D 93 Bitstring 1 CMPUSRX2 Reserved for non-IBM use 005E 94 Bitstring 1 CMPUSRX3 Reserved for non-IBM use 005F 95 Bitstring 1 CMPUSRX4 Reserved for non-IBM use 0060 96 Dbl-Word 8 CMPEXTND (0) Start of variable length data The CMPBK may be extended at allocation time in units of quad-words (16 bytes) 00000060 CMPBSIZE *-CMPBK Size of CMPBK in bytes 0000000C CMPSIZE (*-CMPBK+7)/8 Size in double words
 
 
  CMPBK Storage Layout Top of page
 
          
*** CMPBK - Component Id Block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       CMPBKLK                         =
*     |                                                       |
*     +---------------------------+------+--------------------+
*  18 |          CMPFWD           |:EXTNQ|       CMPID        |
*     +---------------------------+------+--------------------+
*  20 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  28 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  30 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  38 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  40 |                       CMPUSRD1                        |
*     +-------------------------------------------------------+
*  48 |                       CMPUSRD2                        |
*     +---------------------------+---------------------------+
*  50 |         CMPUSRF1          |         CMPUSRF2          |
*     +-------------+-------------+------+------+------+------+
*  58 |  CMPUSRH1   |  CMPUSRH2   |:USRX1|:USRX2|:USRX3|:USRX4|
*     +-------------+-------------+------+------+------+------+
*
*** CMPBK - Component Id Block
 
 
  CMPBK Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
CMPBKLK        0000
CMPBSIZE       0060 00000060
CMPEXTND       0060
CMPEXTNQ       001C
CMPFWD         0018
CMPID          001D
CMPSIZE        0060 0000000C
CMPUSRD1       0040
CMPUSRD2       0048
CMPUSRF1       0050
CMPUSRF2       0054
CMPUSRH1       0058
CMPUSRH2       005A
CMPUSRX1       005C
CMPUSRX2       005D
CMPUSRX3       005E
CMPUSRX4       005F
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:48:10 EDT.
Copyright IBM Corporation, 1990, 2022