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.
 RELOCATION CONSIDERATIONS : None

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