DBIRQ

Prolog  

Control Block Contents  
   DBIRQ DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  

DBIRQ Prolog

 NAME       : HCPDBIRQ
 DESCRIPTION: DASD BLOCK I/O SSCH REQUEST DATA
 DSECT      : DBIRQ
 FUNCTION   : This DSECT maps data for DASD block I/O
              system service to honor one IUCV SEND request,
              and for DIAGNOSE X'250' to honor one read/write
              request.
 LOCATED BY : BLKDBIAD field in HCPBLKIO
              BKIDBIRQ field in HCPBKIBK
 CREATED BY : HCPBIM, for *BLOCKIO
              HCPBIR, for DIAGNOSE X'250' read/write
              requests.
 DELETED BY : HCPBIM, for *BLOCKIO
              HCPBIR, for DIAGNOSE X'250' read/write
              requests.
 SERIALIZED : Unique task execution
              VMDBK dispatch lock.
              For *BLOCKIO, the chain of DBIRQs is
              protected by the BLKIO lock, in HCPBLKIO.
              For DIAGNOSE X'250', the chain of DBIRQs is
              protected by the BKIBK lock in HCPBKIBK.

DBIRQ Control Block Content

DBIRQ DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      DBIRQ          DASD BLOCK I/O SSCH REQUEST DATA
0000    0 Address      4 DBIPREV        Previous Outstanding DBIRQ
0004    4 Address      4 DBINEXT        Next Outstanding DBIRQ
0008    8 Address      4 DBIIORBK       IORBK Associated with Request
000C   12 Signed       4 *              Reserved for Future IBM Use
0010   16 Bitstring   24 DBIIRASV       Save area for interrupt return
          00000005       DBISIZE        (*-DBIRQ+7)/8 Size, in
                                        doublewords, of DBIRQ

DBIRQ Storage Layout

          
*** DBIRQ - DASD BLOCK I/O SSCH REQUEST DATA
*
*     +---------------------------+---------------------------+
*   0 |         DBIPREV           |         DBINEXT           |
*     +---------------------------+---------------------------+
*   8 |         DBIIORBK          |///////////////////////////|
*     +---------------------------+---------------------------+
*  10 |                                                       |
*     =                       DBIIRASV                        =
*     |                                                       |
*     +-------------------------------------------------------+
*  28
*
*** DBIRQ - DASD BLOCK I/O SSCH REQUEST DATA

DBIRQ Cross Reference

Symbol         Dspl Value
-------------- ---- -----
DBIIORBK       0008
DBIIRASV       0010
DBINEXT        0004
DBIPREV        0000
DBISIZE        0010 00000005