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

GCCW

Prolog  

Control Block Contents  
   GCCW DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  


GCCW Prolog

 NAME       : HCPGCCW
 DESCRIPTION: GUEST CHANNEL CONTROL WORD MAPPING
 DSECT      : GCCW
 FUNCTION   : PROVIDE SYMOLIC REFERENCES FOR THE FIELDS OF A CCW
              FOR A VIRTUAL MACHINE
 LOCATED BY : N/A
 CREATED BY : N/A
 DELETED BY : N/A

 

GCCW Control Block Content


GCCW DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      GCCW           GUEST CHANNEL CONTROL WORD
                                        MAPPING
0000    0 Dbl-Word     8 GCCWDWRD       CCW STRUCTURE
0000    0 Signed       4 GCCW0WD0 (0)   FIRST WORD OF CCW
0000    0 Bitstring    1 GCCW0CMD       CCW COMMAND CODE
0001    1 Address      3 GCCW0ADR       CCW ADDRESS (24-BIT)
0004    4 Signed       4 GCCW0WD1 (0)   SECOND WORD OF CCW
0004    4 Bitstring    1 GCCW0FLG       CONTROL OF CCW FLAGS
          1... ....      CCWDC          X'80' CHAIN DATA ADDRESS AND
                                        COUNT
          .1.. ....      CCWCC          X'40' COMMAND CHAIN
          ..1. ....      CCWSILI        X'20' SUPPRESS INCORRECT LENGTH
          ...1 ....      CCWSKIP        X'10' SUPPRESS INBOUND DATA
                                        TRANSFER
          .... 1...      CCWPCIR        X'08' REQUEST PC INTERRUPTION
          .... .1..      CCWIDA         X'04' INDIRECT DATA ADDRESSING
          .... ..11      CCWINVAL       X'03' I/O UNDEFINED PAIR OF BITS
          .... ..1.      CCWSUSPN       X'02' I/O SUSPENSION/RESUMPTION
          .... ...1      CCWUNDEF       X'01' I/O UNDEFINED BIT
0005    5 Bitstring    1 GCCW0SPL       FORMAT 0 "UNUSED" BYTE.
0006    6 Signed       2 GCCW0CNT       COUNT FOR I/O
0008    8 Dbl-Word     8 GCCW0NXT (0)   NEXT GUEST CCW
          00000007       GCCW0IS        B'0111' INSERT MASK
          00000080       GCCW0IDL       B'10000000' IDAL INVALID BITS
                                        MASK
          00000008       GCCW0LEN       8 LENGTH OF A FORMAT 0 CCW
0000    0 Signed       4 GCCW1WD0 (0)   FIRST WORD OF CCW
0000    0 Bitstring    1 GCCW1CMD       CCW COMMAND CODE
0001    1 Bitstring    1 GCCW1FLG       CONTROL OF CCW FLAGS
          1... ....      CCWDC          X'80' CHAIN DATA ADDRESS AND
                                        COUNT
          .1.. ....      CCWCC          X'40' COMMAND CHAIN
          ..1. ....      CCWSILI        X'20' SUPPRESS INCORRECT LENGTH
          ...1 ....      CCWSKIP        X'10' SUPPRESS INBOUND DATA
                                        TRANSFER
          .... 1...      CCWPCIR        X'08' REQUEST PC INTERRUPTION
          .... .1..      CCWIDA         X'04' INDIRECT DATA ADDRESSING
          .... ..11      CCWINVAL       X'03' I/O UNDEFINED PAIR OF BITS
          .... ..1.      CCWSUSPN       X'02' I/O SUSPENSION/RESUMPTION
          .... ...1      CCWUNDEF       X'01' I/O UNDEFINED BIT
0002    2 Signed       2 GCCW1CNT       COUNT FOR I/O
0004    4 Signed       4 GCCW1WD1 (0)   SECOND WORD OF CCW
0004    4 Address      4 GCCW1ADR       CCW ADDRESS (31-BIT)
0008    8 Dbl-Word     8 GCCW1NXT (0)   NEXT GUEST CCW
          0000000F       GCCW1IS        B'1111' INSERT MASK
          00000080       GCCW1IDL       B'10000000' IDAL INVALID BIT MASK
          00000008       GCCW1LEN       8 LENGTH OF A FORMAT 1 CCW

 

GCCW Storage Layout

          
*** GCCW - GUEST CHANNEL CONTROL WORD MAPPING
*
*     +-------------------------------------------------------+
*   0 |                       GCCWDWRD                        |
*     +-------------------------------------------------------+
*   8
*
*** GCCW - GUEST CHANNEL CONTROL WORD MAPPING
          
*** Overlay for GCCWDWRD in GCCW
*
*     +------+--------------------+------+------+-------------+
*   0 |:W0CMD|     GCCW0ADR       |:W0FLG|:W0SPL|  GCCW0CNT   |
*     +------+--------------------+------+------+-------------+
*
*** Overlay for GCCWDWRD in GCCW
          
*** Overlay for GCCWDWRD in GCCW
*
*     +------+------+-------------+---------------------------+
*   0 |:W1CMD|:W1FLG|  GCCW1CNT   |         GCCW1ADR          |
*     +------+------+-------------+---------------------------+
*
*** Overlay for GCCWDWRD in GCCW

 

GCCW Cross Reference

Symbol         Dspl Value
-------------- ---- -----
CCWCC          0004 40
CCWCC          0001 40
CCWDC          0004 80
CCWDC          0001 80
CCWIDA         0004 04
CCWIDA         0001 04
CCWINVAL       0004 03
CCWINVAL       0001 03
CCWPCIR        0004 08
CCWPCIR        0001 08
CCWSILI        0004 20
CCWSILI        0001 20
CCWSKIP        0004 10
CCWSKIP        0001 10
CCWSUSPN       0004 02
CCWSUSPN       0001 02
CCWUNDEF       0004 01
CCWUNDEF       0001 01
GCCWDWRD       0000
GCCW0ADR       0001
GCCW0CMD       0000
GCCW0CNT       0006
GCCW0FLG       0004
GCCW0IDL       0008 00000080
GCCW0IS        0008 00000007
GCCW0LEN       0008 00000008
GCCW0NXT       0008
GCCW0SPL       0005
GCCW0WD0       0000
GCCW0WD1       0004
GCCW1ADR       0004
GCCW1CMD       0000
GCCW1CNT       0002
GCCW1FLG       0001
GCCW1IDL       0008 00000080
GCCW1IS        0008 0000000F
GCCW1LEN       0008 00000008
GCCW1NXT       0008
GCCW1WD0       0000
GCCW1WD1       0004

This information is based on z/VM V4R2.0. Last updated on 17 Oct 2001 at 15:23:00 EDT.
Copyright IBM Corporation, 1990, 2001