Programming Interface Information: This information is NOT intended to be
used as Programming Interfaces of z/VM.

IOPBK

Prolog
Control Block Contents
IOPBK DSECT
Storage Layout
Cross Reference

IOPBK Prolog

 NAME       : HCPIOPBK
 DESCRIPTION: I/O Passthrough Block
 DSECT      : IOPBK
 FUNCTION   : A IOPBK contains information related to the
              execution of a virtual machine eligible to use
              the SIE Assist for its dedicated I/O.
 LOCATED BY : VMDIOPBK  Field of the preferred guest's Origin
              VMDBK
              The first part of the IOPBK is a TRQBK, so it may
              also appear on the timer supervisor queue, or be
              stacked on the VMDBK.
 CREATED BY : HCPBVM    When a user logs on in the V=R area.
 DELETED BY : HCPUSO    When the V=R user logs off.

 

IOPBK Control Block Content

IOPBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      IOPBK          I/O Passthrough Block
     OPTRQBK DS (TRQSIZE)D Timer Request Block
0000    0 Dbl-Word     8 IOPTRQBK (7)   Timer Request Block
     <CMT>* DS (LKWRDSIZ)D Lockword for synchronizing
0038   56 Dbl-Word     8 IOPLKWRD (3)   Lockword for synchronizing the
                                        timer exit and the cancellation
                                        routine
0050   80 Signed       4 IOPTMCNT       count of entries to CFM while I/O
                                        Passthrough was active
0054   84 Signed       4 IOPXTCNT       count of timer expirations before
                                        cancellations
0058   88 Signed       4 IOPQQCNT       count of cancellations in less
                                        than 1024 microseconds
005C   92 Signed       4 IOPLLCNT       count of cancellation after more
                                        than 64 sec
0060   96 Signed       4 IOPXCNTS (16)  array of counts of cancellations
                                        in interval with lower bound
                                        1024*(2**i) microseconds (i = 0 .
                                        15)
00A0  160 Signed       4 IOPIFSNT       Address of the 16K block assigned
                                        to this user for use as the
                                        subchannel number table
00A4  164 Bitstring    1 IOPACTZN       Active zone number
00A5  165 Bitstring    1 * (3)          Reserved
00A8  168 Signed       4 IOPCLRCC       CLEAR CHANNEL CONDITION CODE
00AC  172 Signed       4 *              Reserved for Future IBM Use
00B0  176 Dbl-Word     8 *              Reserved for Future IBM Use
          000000B8       IOPLEN         *-IOPBK Size of the IOPBK in
                                        bytes
          00000017       IOPSIZE        (IOPLEN+7)/8 Size of the IOPBK in
                                        doublewords

 

IOPBK Storage Layout

          
*** IOPBK - I/O Passthrough Block
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       IOPTRQBK                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  38 |                                                       |
*     =                       IOPLKWRD                        =
*     |                                                       |
*     +---------------------------+---------------------------+
*  50 |         IOPTMCNT          |         IOPXTCNT          |
*     +---------------------------+---------------------------+
*  58 |         IOPQQCNT          |         IOPLLCNT          |
*     +---------------------------+---------------------------+
*  60 |                                                       |
*     =                       IOPXCNTS                        =
*     |                                                       |
*     +---------------------------+------+--------------------+
*  A0 |         IOPIFSNT          |:ACTZN|////////////////////|
*     +---------------------------+------+--------------------+
*  A8 |         IOPCLRCC          |///////////////////////////|
*     +---------------------------+---------------------------+
*  B0 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  B8
*
*** IOPBK - I/O Passthrough Block

 

IOPBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
IOPACTZN       00A4
IOPCLRCC       00A8
IOPIFSNT       00A0
IOPLEN         00B0 000000B8
IOPLKWRD       0038
IOPLLCNT       005C
IOPQQCNT       0058
IOPSIZE        00B0 00000017
IOPTMCNT       0050
IOPTRQBK       0000
IOPXCNTS       0060
IOPXTCNT       0054

This information is based on z/VM V3R1.0.
Last updated on 29 Mar 2001 at 15:54:21 EDT.
Copyright IBM Corporation, 1990, 2001