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

DIOSECT

Prolog  

Control Block Contents  
   DIOSECT DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  


DIOSECT Prolog

 Name       : DIOSECT
 Description: Disk I/O Work Area
 DSECT      : DIOSECT
 Notes      : MODULE TYPE - Macro
 Function   : This is the bilingual macro
              containing the mapping of the disk I/O work
              area used primarily by module DMSDIO. DIOSECT
              describes the fields used by DMSDIO as a work
              area when reading and writing actual blocks of
              data on CMS disks. DIOSECT is pointed to by a
              V-constant in DMSNUC, and referenced indirectly
              by ADIOSECT in NUCON.

 

DIOSECT Control Block Content


DIOSECT DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      DIOSECT        Disk I/O Work Area
0000    0 Dbl-Word     8 IOOLD          IO-OLD-PSW (FROM INTERRUPT
                                        ROUTINE)
0008    8 Dbl-Word     8 DIOCSW         CSW (FROM INTERRUPT ROUTINE)
     WAIT CALLING SEQUENCE
0010   16 Signed       4 * (0)
0010   16 Character    8 PWAIT
0018   24 Character    4 *              FILLED IN TO CORRECT SYMBOLIC
                                        DISK NO.
001C   28 Signed       4 *
0020   32 Signed       4 *
0024   36 Signed       4 QQDSK1         1ST TWO BYTES ALWAYS = 0
          ..1. .11.      QQDSK2         QQDSK1+2 HALFWORD COPY OF 16TH
                                        TRACK DISK-ADDRESS CCW CHAIN
0050   80 Bitstring    7 SEEKADR        SEEK/SEARCH INFO (1ST 3 BYTES ARE
                                        0)
0057   87 Bitstring    1 SECTNUM        SECTOR NUMBER
     FBA CCWS FOR USE IN ONE-CMS-BLK OPERATIONS
     FULL MINIDISK NEXT OPERATION
     DEFINE EXTENT LIST
0070  112 Bitstring    1 FBACD1         MASK
0071  113 Bitstring    3 *              RESERVED
0074  116 Signed       4 FBACD1MO       MAJOR OFFSET
0078  120 Signed       4 FBACD1FB       FIRST BLOCK OFFSET
007C  124 Signed       4 FBACD1LB       LAST BLOCK OFFSET
     LOCATE LIST
0080  128 Bitstring    1 FBACL1         OPERATION
0081  129 Bitstring    1 *              AUX BYTE
0082  130 Signed       2 FBACL1NB       NUMBER OF BLKS
0084  132 Signed       4 FBACL1BO       BLOCK OFFSET
     I/O INFO
0088  136 Signed       4 LASTCYL        BECOMES 'LAST CYLINDER-NUMBER
                                        USED'
008C  140 Signed       4 LASTHED        BECOMES 'LAST HEAD-NUMBER USED'
0090  144 Bitstring    1 DEVTYP         Device type from the DEVTAB
0091  145 Bitstring    1 DIOFLAG        RDTK/WRTK FLAG:
          .1.. ....      DIODYBUF       X'40' DYnamic BUFfer obtained
          ..1. ....      DIOFLSB        X'20' Sense bytes stored on I/O
                                        error
          ...1 ....      DIOFLCSW       X'10' CSW stored on I/O error
          .... .1..      TOOBIG         X'04' BYTE-COUNT > 800
          .... ..1.      WRTKF          X'02' WRITING FIRST CHAIN LINK
          .... ...1      QQTRK          X'01' HANDLING FIRST CHAIN LINK
          ...1 1...      DIAGNUM        24 **** NUMBER ASSIGNED BY 'CP'
                                        FOR DIAGNOSE I/O ****
          .... .1..      DIOBKWTH       4 Default block width is 4..
0098  152 Dbl-Word     8 * (0)
0098  152 Bitstring   32 SENSB          SENSE INFORMATION
     MISCELLANEOUS STORAGE...
00C0  192 Dbl-Word     8 DOUBLE         (SCRATCH-AREA, FOR CVD USE ETC.)
     KEEP THE FOLLOWING THREE IN ORDER...
00C8  200 Signed       4 XRSAVE (15)    REGISTERS 0-14 SAVED HERE FOR
                                        RDTK-WRTK
0104  260 Address      3 *              FIRST 3 BYTES OF R15 ERROR-CODE
0107  263 Address      1 ERRCODE        ERROR-CODE (IN R15 AT EXIT)
     KEEP THE FOLLOWING TWO IN ORDER..
0108  264 Signed       4 FREER0         NO. DBL-WORDS OF FREE STORAGE (IF
                                        ANY)
010C  268 Signed       4 DIOFREE        ADD. OF FREE STORAGE FOR BUFFER
                                        OR CCW'S
0110  272 Signed       2 DIOSNSCT       SENSE BYTE COUNT
0112  274 Signed       2 *              RESERVED
0120  288 Bitstring    1 DIAGRET        CP'S DIAGNOSE RETURN CODE IF
                                        NON-ZERO
0121  289 Bitstring    1 IOCOMM         SET TO READ (06) OR WRITE (05)
0122  290 Bitstring    1 LASTREC        NUMBER (1-14) OF THE LAST RECORD
                                        PROCESSED
0128  296 Dbl-Word     8 DIOCCW01 (128) CCW BUILD AREA FOR LONG
                                        OPERATIONS VA09499
          00000080       DIOCCWLN       (*-DIOCCW01)/8 Number of Dwords
                                        in work area
0528 1320 Signed       4 DIODIEPL (7)   Reserve storage for DISKDIE
                                        parameter list
0544 1348 Signed       4 *              Reserved
0548 1352 Dbl-Word     8 * (0)
0128  296 Signed       4 DIOBUFEN       Max number of SBILIST entries
                                        that can be built in the workarea
0130  304 Dbl-Word     8 DIOSBIOP (11)  SBIOP block build area
          0000000C       DIODWUSD       (*-DIOCCW01)/8 Number of d-words
                                        used
0188  392 Dbl-Word     8 DIOSBL01 (0)   SBILIST build area
          .111 .1..      DIOSBLMX       DIOCCWLN-DIODWUSD Number of
                                        SBILISTS buildable in static save
                                        area
     ECKD CCW CHAIN
0560 1376 Signed       4 * (0)          Set up alignment
0560 1376 Bitstring   16 DIODEX (0)     Define extent parameter list
0560 1376 Bitstring    1 DIOMASK        Mask byte
0561 1377 Bitstring    1 DIOATTRB       Extended CKD implemented
0562 1378 Signed       2 DIOBLKSZ       Maximum block size allowed
0564 1380 Bitstring    3 *              RESERVED /*VA59119*/
0567 1383 Bitstring    1 DIOGLOA7       Global attribute byte seven
                                        /*VA59119*/
          .1.. ....      DIOR0FMT       X'40' R0 is standard /*VA59119*/
0568 1384 Signed       2 DIOBEGCC       Beginning cylinder extent
056A 1386 Signed       2 DIOBEGHH       Beginning head extent
056C 1388 Signed       2 DIOENDCC       End cylinder extent
056E 1390 Signed       2 DIOENDHH       End head extent
0570 1392 Signed       4 * (0)          Set up alignment
0570 1392 Bitstring   16 DIOLOC (0)     Locate record parameter list
0570 1392 Bitstring    1 DIOOPBYT       OP code byte
0571 1393 Bitstring    1 DIOAUX         Auxiliary byte
0572 1394 Bitstring    1 *              RESERVED - SET TO ZEROS
0573 1395 Bitstring    1 DIORECNO       Number of records to process
0574 1396 Signed       2 DIOSEEKC       Seek cylinder
0576 1398 Signed       2 DIOSEEKH       Seek head
0578 1400 Signed       2 DIOSRCHC       Search cylinder
057A 1402 Signed       2 DIOSRCHH       Search head
057C 1404 Bitstring    1 DIOSRCHR       Search record number
057D 1405 Bitstring    1 DIOSSECT       Sector number
057E 1406 Signed       2 DIOTLF         Transfer length factor
     ** CMS EQUATE SYMBOLS

 

DIOSECT Storage Layout

          
*** DIOSECT - Disk I/O Work Area
*
*     +-------------------------------------------------------+
*   0 |                        IOOLD                          |
*     +-------------------------------------------------------+
*   8 |                        DIOCSW                         |
*     +-------------------------------------------------------+
*  10 |                        PWAIT                          |
*     +---------------------------+---------------------------+
*  18 |///////////////////////////|///////////////////////////|
*     +---------------------------+---------------------------+
*  20 |///////////////////////////|          QQDSK1           |
*     +---------------------------+---------------------------+
*  28 |///////////////////////////////////////////////////////|
*     =///////////////////////////////////////////////////////=
*     |///////////////////////////////////////////////////////|
*     +------------------------------------------------+------+
*  50 |                    SEEKADR                     |:TNUM |
*     +------------------------------------------------+------+
*  58 |///////////////////////////////////////////////////////|
*     =///////////////////////////////////////////////////////=
*     |///////////////////////////////////////////////////////|
*     +------+--------------------+---------------------------+
*  70 |FBACD1|////////////////////|         FBACD1MO          |
*     +------+--------------------+---------------------------+
*  78 |         FBACD1FB          |         FBACD1LB          |
*     +------+------+-------------+---------------------------+
*  80 |FBACL1|//////|  FBACL1NB   |         FBACL1BO          |
*     +------+------+-------------+---------------------------+
*  88 |         LASTCYL           |         LASTHED           |
*     +------+------+-------------+---------------------------+
*  90 |DEVTYP|:FLAG |/////////////////////////////////////////|
*     +------+------+-----------------------------------------+
*  98 |                                                       |
*     =                        SENSB                          =
*     |                                                       |
*     +-------------------------------------------------------+
*  B8 |///////////////////////////////////////////////////////|
*     +-------------------------------------------------------+
*  C0 |                        DOUBLE                         |
*     +-------------------------------------------------------+
*  C8 |                                                       |
*     =                        XRSAVE                         =
*     |                           +--------------------+------+
* 100 |                           |////////////////////|:CODE |
*     +---------------------------+--------------------+------+
* 108 |          FREER0           |         DIOFREE           |
*     +-------------+-------------+---------------------------+
* 110 |  DIOSNSCT   |/////////////|///////////////////////////|
*     +-------------+-------------+///////////////////////////|
*     |///////////////////////////////////////////////////////|
*     +------+------+------+----------------------------------+
* 120 |:GRET |IOCOMM|:TREC |//////////////////////////////////|
*     +------+------+------+----------------------------------+
* 128 |                                                       |
*     =                       DIOCCW01                        =
*     |                                                       |
*     +-------------------------------------------------------+
* 528 |                                                       |
*     =                       DIODIEPL                        =
*     |                           +---------------------------+
* 540 |                           |///////////////////////////|
*     +---------------------------+---------------------------+
* 548 |///////////////////////////////////////////////////////|
*     =///////////////////////////////////////////////////////=
*     |///////////////////////////////////////////////////////|
*     +------+------+-------------+--------------------+------+
* 560 |:MASK |:ATTRB|  DIOBLKSZ   |////////////////////|:GLOA7|
*     +------+------+-------------+-------------+------+------+
* 568 |  DIOBEGCC   |  DIOBEGHH   |  DIOENDCC   |  DIOENDHH   |
*     +------+------+------+------+-------------+-------------+
* 570 |:OPBYT|DIOAUX|//////|:RECNO|  DIOSEEKC   |  DIOSEEKH   |
*     +------+------+------+------+------+------+-------------+
* 578 |  DIOSRCHC   |  DIOSRCHH   |:SRCHR|:SSECT|   DIOTLF    |
*     +-------------+-------------+------+------+-------------+
* 580
*
*** DIOSECT - Disk I/O Work Area
          
*** Overlay for DIOCCW01 in DIOSECT
*
*     +---------------------------+---------------------------+
* 128 |         DIOBUFEN          |///////////////////////////|
*     +---------------------------+---------------------------+
* 130 |                                                       |
*     =                       DIOSBIOP                        =
*     |                                                       |
*     +-------------------------------------------------------+
*
*** Overlay for DIOCCW01 in DIOSECT

 

DIOSECT Cross Reference

Symbol         Dspl Value
-------------- ---- -----
DEVTYP         0090
DIAGNUM        0091 18
DIAGRET        0120
DIOATTRB       0561
DIOAUX         0571
DIOBEGCC       0568
DIOBEGHH       056A
DIOBKWTH       0091 04
DIOBLKSZ       0562
DIOBUFEN       0128
DIOCCWLN       0128 00000080
DIOCCW01       0128
DIOCSW         0008
DIODEX         0560
DIODIEPL       0528
DIODWUSD       0130 0000000C
DIODYBUF       0091 40
DIOENDCC       056C
DIOENDHH       056E
DIOFLAG        0091
DIOFLCSW       0091 10
DIOFLSB        0091 20
DIOFREE        010C
DIOGLOA7       0567
DIOLOC         0570
DIOMASK        0560
DIOOPBYT       0570
DIORECNO       0573
DIOR0FMT       0567 40
DIOSBIOP       0130
DIOSBLMX       0188 74
DIOSBL01       0188
DIOSEEKC       0574
DIOSEEKH       0576
DIOSNSCT       0110
DIOSRCHC       0578
DIOSRCHH       057A
DIOSRCHR       057C
DIOSSECT       057D
DIOTLF         057E
DOUBLE         00C0
ERRCODE        0107
FBACD1         0070
FBACD1FB       0078
FBACD1LB       007C
FBACD1MO       0074
FBACL1         0080
FBACL1BO       0084
FBACL1NB       0082
FREER0         0108
IOCOMM         0121
IOOLD          0000
LASTCYL        0088
LASTHED        008C
LASTREC        0122
PWAIT          0010
QQDSK1         0024
QQDSK2         0024 26
QQTRK          0091 01
SECTNUM        0057
SEEKADR        0050
SENSB          0098
TOOBIG         0091 04
WRTKF          0091 02
XRSAVE         00C8

This information is based on z/VM V4R3.0.
Last updated on 1 May 2002 at 14:16:08 EDT.
Copyright IBM Corporation, 1990, 2002