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

#### IORBK

Prolog

Control Block Contents
IORBK DSECT

Storage Layout

Cross Reference (Contains links to field and bit definitions)

#### IORBK Prolog

     NAME       : HCPIORBK
     DESCRIPTION: I/O Request and Response Block
     DSECT      : IORBK
     FUNCTION   : THE I/O REQUEST AND RESPONSE BLOCK IS USED
                  TO REPRESENT AN I/O OPERATION.
     LOCATED BY : CACXUIOR FIELD OF CACBK - CTC UNSOLICITED IORBK
                  CACYUIOR FIELD OF CACBK - CTC UNSOLICITED IORBK
                  CPVIORS  FIELD OF CPVOL - PREFORMATTED PAGING IORBK
                  GSRIORBK FIELD OF GSRBK - IORBK'S FOR RECOVERY
                  IORFPNT  FIELD OF IORBK - FORWARD  IORBK POINTER
                  IORBPNT  FIELD OF IORBK - BACKWARD IORBK POINTER
                  IORPIOR  FIELD OF IORBK - NEXT PENDING INTERRUPTION IORBK
                  MDIDEOWD FIELD OF MDISK - DEVICE-END OWED IORBK
                  MDIDEPND FIELD OF MDISK - DEVICE-END PENDING IORBK
                  MDIQWAIT FILED OF MDISK - WAIT FOR "RELEASE" IORBK
                  MNDAIOR  FIELD OF MNDC  - MONITOR TAPE IORBK
                  PIOIOR   FIELD OF PIOBK - IORBK FOR THIS PIOBK
                  RDEVAIOR FIELD OF RDEV  - ACTIVE IORBK
                  RDEVNXTL FIELD OF RDEV  - NEXT LOWER  IORBK
                  RDEVNXTH FIELD OF RDEV  - NEXT HIGHER IORBK
                  RDEVNXTI FIELD OF RDEV  - NEXT IMMEDIATE IORBK
                  RDEVNXTW FIELD OF RDEV  - INTER-REQUIRED WAIT IORBK
                  VCTXDATN FIELD OF VCTCA - DEFERRED ATTENTION IORBK
                  VCTYDATN FIELD OF VCTCA - DEFERRED ATTENTION IORBK
                  VDEVAIOR FIELD OF VDEV  - ACTIVE IORBK
                  VDEVIORQ FIELD OF VDEV  - UNSOLICITED INTERRUPT IORBK
                  VDEVNIOR FIELD OF VDEV  - REDRIVE/SUSPENDED IORBK
                  VDEVPIOR FIELD OF VDEV  - PENDING INTERRUPT IORBK
                  VDEVSIOR FIELD OF VDEV  - PENDING SENSE DATA IORBK
                  VMDQIORF FIELD OF VMDBK - IORBK/TRQBK STACK
     CREATED BY : IORBK'S ARE DYNAMICALLY CREATED BY CALLING HCPFREE.
     DELETED BY : IORBK'S ARE DELETED BY CALLING HCPFRET.

#### IORBK Control Block Content

#### IORBK DSECT

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      IORBK          I/O Request and Response Block
         WARNING - THE FIRST THREE DOUBLE WORDS MUST BE IDENTICAL TO THE TRQBK
         COPY FILE.
    0000    0 Signed       4 IORUSER        VIRTUAL USER TO BE CHARGED
    0004    4 Signed       4 IORIRA         I/O INTERRUPTION RETURN ADDR.
    0008    8 Signed       4 IORFPNT        POINTER TO NEXT QUEUED IORBK
    000C   12 Signed       4 IORBPNT        POINTER TO PREVIOUS QUEUED IORBK
    0010   16 Signed       4 IORDISPN (0)   DISPATCHING FLAGS
    0010   16 Bitstring    1 IORQSTAT       DISPATCHING QUEUING STATUS
              1... ....      IORQQUED       X'80' WAITING AFTER STARTING I/O
              .1.. ....      IORQACTV       X'40' ACTIVE IN CHANNEL
              ..1. ....      IORQDSP        X'20' DISPATCHER HAS CONTROL OF
                                            IORBK
              ...1 ....      IORACT         X'10' ACTIVE I/O
              .... ...1      IORQANCH       X'01' CHANNEL SCHEDULING QUEUE
                                            (ANCHOR)
    0011   17 Bitstring    1 *              RESERVED FOR FUTURE IBM USE
    0012   18 Bitstring    1 IORSCHED       SCHEDULING, UNSTACK CONTROL FLAGS
              1... ....      IORHIPRI       X'80' REQUEST TO GRANT A VERY
                                            HIGH DISPATCHER/SCHEDULER
                                            PRIORITY FOR THE VMDBK IDENTIFIED
                                            BY IORUSER
              .1.. ....      IORUCALL       X'40' UNSTACK IORBK WITH
                                            CALL-LINKAGE WHEN UNSTACKED BY
                                            THE DISPATCHER
              ..1. ....      IORFULLR       X'20' Target IRA is a fullreg
                                            entry point.
              .... ...1      IORIDTRQ       X'01' TRQBK IDENTIFIER (1=TRQBK,
                                            0=IORBK)
    0013   19 Bitstring    1 *              RESERVED FOR FUTURE IBM USE
    0014   20 Signed       4 *              RESERVED FOR FUTURE IBM USE
    0018   24 Signed       4 IORSAVE        LOCATION TO SAVE R13 FOR IORSYN
                                            HCPPAG USES THIS FIELD AS THE
                                            POINTER IN A SINGLY LINKED LIST
                                            OF IORBKS. HCPCPH USES THIS FIELD
                                            AS THE POINTER TO A HLTBLK.
                                            HCPCPH WILL RESTORE THIS FIELD TO
                                            ITS ORIGINAL VALUE WHEN HALT
                                            PROCESSING IS COMPLETE.
    001C   28 Signed       4 IORPIOR        PENDING INTERRUPTION LIST
    0020   32 Signed       4 IORTASK        ADDRESS OF RCWTASK/CONTASK CHAIN
    0024   36 Signed       4 IORRDFND       ADDR OF 3270 FULL SCREEN READ
    0028   40 Signed       2 IORTYGBL       E.R.P. GLOBAL RETRY COUNT
              00000801       IORMXGCT       2049 MAXIMUM GLOBAL RETRY COUNT
    002A   42 Signed       2 IORTYLCL       E.R.P. LOCAL RETRY COUNT
    002C   44 Signed       2 IORECLVL       E.R.P. RECURSION LEVEL
              0000000A       IORMXRCT       10 MAXIMUM RECURSIVE COUNT
    002E   46 Signed       2 IORETCOD       E.R.P. COMPLETION CODE
              00000000       IORRCOK        0 SUCCESSFUL COMPLETION
              00000004       IORRCDRV       4 REDRIVE / RESUME
              00000008       IORRCEOF       8 END-OF-FILE
              0000000C       IORRCFTL       12 FATAL I/O COMPLETION
              00000010       IORRCKIL       16 SEVERE I/O ERROR
              00000014       IORRCNCL       20 I/O CANCELLED
    0030   48 Signed       4 IORVDEV        ADDRESS OF VIRTUAL DEVICE BLOCK
         OPERATION REQUEST BLOCK
    0034   52 Bitstring   32 IORORB (0)     OPERATION REQUEST BLOCK
    0034   52 Signed       4 IORRDEV        ADDRESS OF REAL DEVICE BLOCK
                                            (PARM)
    0038   56 Signed       4 IOROCTL (0)    FOLLOWING ARE CONTROL FIELDS
    0038   56 Bitstring    2 IOROKF (0)     KEY AND FLAG BYTES
    0038   56 Bitstring    1 IOROKEY        KEY PLUS 4 REQUIRED ZEROS
    0039   57 Bitstring    1 IOROFPI        FETCH, PROTECT AND INITIAL STATUS
    003A   58 Bitstring    1 IOROLPM        LOGICAL PATH MASK
    003B   59 Bitstring    1 IOROORB7       BYTE 7 OF SYSTEM ORB
    003C   60 Signed       4 IORCCWS (0)    FIRST CHANNEL COMMAND WORD
    003C   60 Signed       4 IORCPA         CHANNEL PROGRAM ADDRESS
    0040   64 Bitstring   20 IORXOWDS (0)   Extended portion of the ORB
    0040   64 Signed       4 IOROWRD3 (0)   ORB word 3
    0040   64 Bitstring    1 IORPRTY        I/O priority for channel
                                            subsystem
    0041   65 Bitstring    1 IOROW3B1       ORB word 3 byte 1
    0042   66 Bitstring    1 IOROW3B2       ORB word 3 byte 2
    0043   67 Bitstring    1 IOROW3B3       ORB word 3 byte 3
    0044   68 Signed       4 *              Reserved for future hardware use
    0048   72 Signed       4 *              Reserved for future hardware use
    004C   76 Signed       4 *              Reserved for future hardware use
    0050   80 Signed       4 *              Reserved for future hardware use
         VIRTUAL MACHINE'S ORB CONTROLS
    0054   84 Signed       4 IORUCTL (0)    SAVED GUEST CONTROL FIELD VALUES
    0054   84 Bitstring    2 IORUKF (0)     KEY AND FLAG BYTES
    0054   84 Bitstring    1 IORUKEY        KEY PLUS 4 REQUIRED ZEROS
    0055   85 Bitstring    1 IORUFPI        FETCH, PROTECT AND INITIAL STATUS
    0056   86 Bitstring    1 IORULPM        LOGICAL PATH MASK
    0057   87 Bitstring    1 IORUORB7       BYTE 7 OF GUEST ORB
    0058   88 Signed       4 *              Reserved for IBM use
    005C   92 Signed       4 IORPOSCT       MONITOR DASD ACCESS ARM
                                            POSITIONING COUNT- number of
                                            SEEKS or LOCATEs in the channel
                                            program. Valid when IORDPOSD is
                                            ON.
    0060   96 Signed       4 IORPOSSM       MONITOR DASD ARM MOTION -
                                            distance between first and last
                                            seek or locate in the channel
                                            program in terms of cylinders.
                                            Valid when IORDPOSD is ON.
    0064  100 Signed       4 *              Reserved for IBM use
         INTERRUPT RESPONSE BLOCK
    0068  104 Bitstring   64 IORIRB (0)     INTERRUPTION RESPONSE BLOCK
    0068  104 Bitstring   12 IORSCSW (0)    SUBCHANNEL CSW AREA
    0068  104 Bitstring    2 IORSCTLS (0)   SUBCHANNEL CSW CONTROLS
    0068  104 Bitstring    1 IORSKEY        SCSW KEY, LOGOUT, COND CODE
    0069  105 Bitstring    1 IORFPIZN       CCW CONTROLS & INITIAL RESPONSES
    006A  106 Bitstring    2 IORFCAC (0)    FUNCTION AND ACTIVITY BYTES
    006A  106 Bitstring    1 IORFCTL        FUNCTION CONTROL BYTE
    006B  107 Bitstring    1 IORACTL        ACTIVITY CONTROL PART
    006C  108 Bitstring    8 IORCASC (0)    COMBINED CCW ADDRESS, DEVICE
                                            STATUS, SUBCHANNEL STATUS, AND
                                            RESIDUAL COUNT FIELDS
    006C  108 Signed       4 IORCCWA        SCSW CHANNEL CMD WORD ADDR
    0070  112 Bitstring    4 IORCSC (0)     COMBINED DEVICE STATUS,
                                            SUBCHANNEL STATUS, AND RESIDUAL
                                            COUNT FIELDS
    0070  112 Bitstring    2 IORSTFLG (0)   STATUS FLAG FIELDS TOGETHER
    0070  112 Bitstring    1 IORDVST        SCSW DEVICE STATUS BITS
    0071  113 Bitstring    1 IORSCST        SCSW SUBCHANNEL STATUS BITS
    0072  114 Signed       2 IORCNT         SCSW RESIDUAL CCW DATA COUNT
    0074  116 Signed       4 IORIRLG (0)    LIMITED SUBCHANNEL LOGOUT WORD
    0074  116 Bitstring    1 IORDETCT (0)   S/370 ERROR DETECT FIELD
    0074  116 Bitstring    1 IORECF         ERROR CHECK FLAGS
    0075  117 Bitstring    1 IORSOURC (0)   S/370 ERROR SOURCE FIELD
    0075  117 Bitstring    1 IORLPUM        LAST PATH USED
    0076  118 Signed       2 IORDCTI (0)    DEVICE CONNECT TIME
    0076  118 Bitstring    1 IORFVF         FIELD VALIDITY FLAGS
    0077  119 Bitstring    1 IORTMSEQ       TERMINATION AND SEQUENCE CODES
    0078  120 Signed       4 IORERW (0)     EXTENDED REPORT WORD
    0078  120 Bitstring    1 IORERWB0       EXTENDED REPORT WORD, BYTE 0
    0079  121 Bitstring    1 IORERWB1       Extended Report Word, Byte 1
    007A  122 Bitstring    1 IORERWB2       Extended Report Word, Byte 2
    007B  123 Bitstring    1 IORERWB3       Extended Report Word, Byte 3
    007C  124 Bitstring    8 IORFSA64 (0)   64 bit failing storage address
    007C  124 Signed       4 IORFSA         Failing-Storage Address
    0080  128 Signed       4 *              RESERVED FOR FUTURE HARDWARE USE
    0084  132 Signed       4 IOR2DCCW       Secondary CCW address
    0088  136 Bitstring   32 IORXTLOG       I/O EXTENDED LOGOUT AREA
    00A8  168 Signed       2 IORECYL        LAST CYLINDER USED IN CHANNEL
                                            PROGRAM Valid when IORDPOSD is
                                            turned on.
    00AA  170 Bitstring    6 IORSEEK (0)    BBCCHH FOR COUNT-KEY-DATA
    00AA  170 Bitstring    4 IORSBBCC (0)   BIN AND CYLINDER FOR
                                            COUNT-KEY-DATA
    00AA  170 Signed       2 IORBIN         BIN NUMBER FOR COUNT-KEY-DATA
    00AC  172 Signed       2 IORCYL         CYLINDER NUMBER FOR
                                            COUNT-KEY-DATA Valid when
                                            IORDPOSD is turned on.
    00AE  174 Signed       2 IORHEAD        HEAD NUMBER FOR COUNT-KEY-DATA
    00B0  176 Dbl-Word     8 IORSKCCW (0)   PRELIMINARY SEEK TO BE EXECUTED
    00B0  176 Dbl-Word     8 IORSCCW (0)    SENSE CCW TO BE EXECUTED
    00B0  176 Bitstring    1 IORCCWOC       CCW OPCODE
    00B1  177 Bitstring    1 *              CCW FLAG BYTE
    00B2  178 Signed       2 IORSCNT        CCW COUNT FIELD / SENSE BYTE
                                            COUNT
    00B4  180 Signed       4 *              CCW ADDRESS FIELD
    00B8  184 Signed       4 IOREXTN        POINTER TO EXTENSION DATA
    00BC  188 Signed       4 *              Reserved for IBM use
    00C0  192 Signed       4 IORRCTL (0)    CONTROLS PRESERVED FOR CHANNEL
                                            PROGRAM RESUMPTION (EXCEPT CFLG)
    00C0  192 Signed       2 IORCCTL (0)    CONTROLS PRESERVED FOR CHANNEL
                                            PROGRAM CONTINUATION
    00C0  192 Bitstring    1 IORIFLG        SPECIAL INFORMATION BLOCK
              1... ....      IORCONT        X'80' CHANNEL PROGRAM
                                            CONTINUATION
              .1.. ....      IORMDLCK       X'40' MINI-DISK LOCK HELD FOR
                                            THIS REQUEST
              ..1. ....      IORTRTRM       X'20' TRACE CCW'S FOR TERMINAL
                                            OUTPUT
              ...1 ....      IORTRPRT       X'10' TRACE CCW'S FOR PRINTER
                                            OUTPUT
              ..11 ....      IORTRCCW       IORTRTRM+IORTRPRT TRACE CCW'S FOR
                                            THIS OPERAT'N
              .... 1...      IORRESUM       X'08' CHANNEL PROGRAM RESUMPTION
              .... .1..      IORVXA         X'04' VIRTUAL XA GUEST I/O
                                            REQUEST
              .... ..1.      IORDPOSD       X'02' MONITOR SEEK DATA IS VALID
                                            IORDPOSD validates that IORCYL,
                                            IORECYL, IORPOSCT, IORPOSSM, and
                                            IORDWRIT were filled in when the
                                            channel program was built.
              .... ...1      IORDWRIT       X'01' DASD WRITE OPERATION
                                            Indicates channel program is
                                            write-only OR mixed read/write.
                                            Valid when IORDPOSD is turned on.
    00C1  193 Bitstring    1 IORRFLG        I/O REQUEST CONTROL FLAGS
              1... ....      IORSYNCH       X'80' SYNCHRONOUS. MERGE
                                            SOLICITED STS. IORBK WILL NOT BE
                                            DISPATCHED UNTIL ALL SOLICITED
                                            STATUS IS RECIEVED.
              .1.. ....      IORDQUNS       X'40' DEQUEUE WITH UNSOLICITED
                                            STATUS. IF UNSOLICITED STATUS IS
                                            RECIEVED WHILE THIS IORBK IS
                                            START-PENDING OR ENQUEUED ON A
                                            REAL DEVICE, THE UNSOLICITED
                                            STATUS WILL BECOME THE COMPLETION
                                            STATUS FOR THIS IORBK. THIS DOES
                                            NOT APPLY TO UNSOLICITED
                                            ATTENTION FROM A CTCA. ATTENTION
                                            + BUSY FROM A CTCA IS SOLICITED
                                            WHEN THE SENSE DATA INDICATES
                                            THAT THE COMMANDS ON THE TWO
                                            SIDES OF THE ADAPTOR ARE
                                            CONFLICTING. WHEN THEY ARE NOT
                                            CONFLICTING, THE STATUS IS SIMPLY
                                            DISCARDED.
              ..1. ....      IORERPEQ       X'20' DETECT EQUIPMENT CHECKS
                                            WHICH MAY AFFECT OTHER I/O
                                            REQUESTS FOR THE SAME REAL
                                            DEVICE.
              ...1 ....      IORERPCP       X'10' PERFORM FULL CP I/O ERROR
                                            RECOVERY.
              .... 1...      IORERPNW       X'08' IF REAL DEVICE IS
                                            NOT-READY, DON'T WAIT FOR IT TO
                                            BECOME READY.
              .... .1..      IORUSRIO       X'04' USER (AS OPPOSED TO CP) IO
                                            OPERATION
              .... ..1.      IORHSCH0       X'02' GENERATE NON-FINAL IORBK
                                            FOR CC 0 FROM HOST
                                            HALT-SUBCHANNEL.
              .... ...1      IORDIAG        X'01' GUEST DIAGNOSE INTERFACE
                                            CCWS
    00C2  194 Bitstring    1 IORCFLG        I/O REQUEST COMPLETION FLAGS
              1... ....      IORUNSL        X'80' UNSOLICITED STATUS
              .1.. ....      IORCOPY        X'40' NON-FINAL SOLICITED STATUS
              ..1. ....      IORCCWTR       X'20' CCW TRANSLATION PERFORMED
              ...1 ....      IORNOERP       X'10' ERP INVOCATION NOT ALLOWED
                                            TO PREVENT ERP RECURSION
              .... 1...      IORFTRAN       X'08' Channel program translated
                                            by HCPFTRAN (fast CCW translate)
              .... .1..      IORFATL        X'04' UNRECOVERABLE I/O ERROR
              .... ..1.      IORERDAS       X'02' CALLED FOR DASDI ERRORS
              .... ...1      IORDIA98       X'01' DIAGNOSE X'98' CCW
                                            TRANSLATION
    00C3  195 Bitstring    1 IORCMD         COMMAND FIELD
              00000001       IORSTART       001 START REQUEST - ORB AT IORORB
              00000002       IORHALT        002 HALT REQUEST - CSWRESPN SET
                                            IN IOROFPI TO REQUEST A NON-FINAL
                                            IORBK WHEN CC 0 RECEIVED FOR HSCH
                                            INSTRUCTION.
              00000003       IORHALTD       003 HALTED START REQUEST
              00000004       IORCLEAR       004 CLEAR REQUEST
              00000005       IORMODFY       005 MODIFY REQUEST
              00000006       IORCANCL       006 CANCEL REQUEST
    00C4  196 Bitstring    1 IORSTAT        I/O REQUEST STATUS FLAGS
              1... ....      IORSNSRQ       X'80' SENSE WILL BE REQUIRED
              .1.. ....      IORSNSAC       X'40' SENSE CURRENTLY ACTIVE ON
                                            DEVICE
              ..1. ....      IORSNSIV       X'20' SENSE INFORMATION WILL BE
                                            INVALID
              ...1 ....      IORSNS         X'10' VALID SENSE INFORMATION
                                            PRESENT
              .... 1...      IORCSNAV       X'08' CONCURRENT SENSE DATA IS
                                            ALREADY AVAILABLE
              .... .1..      IOR9C00        X'04' SIO OPERATION
              .... ..1.      IORSIFCC       X'02' ADD INTERFACE CONTROL
                                            CHECK. A MISSING INTERRUPT WAS
                                            DETECTED OR THE DEVICE PRESENTED
                                            INVALID STATUS (ALERT THE USER SO
                                            THE DEVICE WILL BE FIXED)
              .... ...1      IORMBUPD       X'01' GUEST MEASUREMENT BLOCK
                                            UPDATED
    00C5  197 Bitstring    1 IORLMSGF       CFLF Inline Message flag byte
              1... ....      IORLFPSF       X'80' CFLF PSF CCW Simulation
                                            active
              .1.. ....      IORLFRLD       X'40' CFLF Lock Data queued
              ..1. ....      IORLFRID       X'20' CFLF User ID Data queued
              ...1 ....      IORLFATN       X'10' CFLF Attention Message
                                            queued
              .... 1...      IORLFRAD       X'08' CFLF Allocation data queued
              .... .1..      IORLFSSM       X'04' CFLF SSM CCW Simulation
                                            active
    00C6  198 Bitstring    1 IORDFLGS       General I/O Flags
              1... ....      IORD254        X'80' Diagnose 254 I/O request
              .1.. ....      IORDSIC        X'40' Diagnose knocked device out
                                            of SIC
              ..1. ....      IORDIFC        X'20' IFCC forced by IOSBS
              ...1 ....      IORCTRAN       X'10' HCPCTR did the CCW
                                            translation
              .... 1...      IORDCAN        X'08' Active Diagnose 254 request
                                            cancelled by HCPIOSCA
    00C7  199 Address      1 IORTYPE        I/O OPERATION REQUEST TYPE
              00000000       IORSIO         000 START I/O
              000000FE       IORCUSER       254 CHANGE IORUSER TO "SYSTEM"
              000000FF       IORSPECL       255 INFORMATIONAL IORBK
    00C8  200 Bitstring    1 IORXFLG        EXTENDED INFORMATION FLAG
              1... ....      IORCPSUS       X'80' SUSPENDED CHANNEL PROGRAM
              .1.. ....      IORLIFO        X'40' RECOVERY REQUEST - QUEUE IT
                                            LIFO
              ..1. ....      IORISAM        X'20' IORBK CONTAINS ISAM
                                            RCWTASKS
              ...1 ....      IORDISAB       X'10' IORBK CONTAINS DISABLE
                                            RCWTASK
              .... 1...      IORMALPM       X'08' I/O MAY AFFECT PATH MASK
                                            VALIDITY
              .... .1..      IORNOLPM       X'04' DISREGARD RDEVLPM ON SSCH'S
              .... ..1.      IORMSWSP       X'02' SPECIAL PROCESSING
              .... ...1      IORUNLOK       X'01' PAGES ARE NOT LOCKED
    00C9  201 Bitstring    1 IORITFLG       INTERRUPT FLAG
              1... ....      IORFKBSY       X'80' DEVICE STATUS BUSY SET BY
                                            HCPIOS
              .1.. ....      IORTSS         X'40' IORBK used for simulation
                                            by HCPTSS
              ..1. ....      IORHDVA        X'20' ISTAT on HSCH should be
                                            handled, not discarded. This
                                            status is due to the HDV Assist.
              ...1 ....      IORTRASH       X'10' IORBK to be discarded
              .... 1...      IOR370AC       X'08' Vestigial status from a 370
                                            Accommo- dation I/O. Status has
                                            already been presented in a 370
                                            CSW but is being preserved for a
                                            possible TSCH
              .... .1..      IORABUSY       X'04' 370 Accommodation busy. A
                                            condition which causes busy for
                                            370 but not for ESA/XC was
                                            detected. Show the Busy only in
                                            the 370 CSW.
              .... ..1.      IORNODQ        X'02' Prevents previously queued
                                            "non- flush" recovery I/O from
                                            being dequeued during flush ERP's
    00CA  202 Bitstring    1 IORTFLG        TERMINAL CONTROL FLAG
              1... ....      IORCLSCR       X'80' CLEAR SCREEN & ISSUE FULL
                                            SCREEN I/O
    00CB  203 Bitstring    1 IORSWCC        WCC CHARACTER
              .... ...1      IORCSENQ       X'01' REQUEST ENQUEUED ON
                                            RDEVBLOK
              .... ..1.      IORCSWAD       X'02' REQUEST WAITING FOR
                                            AVAILABLE DEV
              .... .1..      IORCSWBY       X'04' REQUEST WAITING FOR BUSY TO
                                            CLEAR
              .... 1...      IORCSTRU       X'08' REQUEST STARTED, NOT
                                            CONFIRMED
              ...1 ....      IORCSTRC       X'10' REQUEST STARTED, CONFIRMED
              ..1. ....      IORCSPCM       X'20' PARTIAL COMPLETION (CE OR
                                            PCI)
              .1.. ....      IORCSHLT       X'40' DEVICE HALTED PRIOR TO
                                            COMPLETION
              1... ....      IORCSFCM       X'80' FULL COMPLETION (SEE
                                            IORTTERM)
    00CC  204 Bitstring    1 IORPFLG        PROCESSING FLAG
              1... ....      IORBKOUT       X'80' An end-user break-out
                                            occurred
              .1.. ....      IORIDONE       X'40' A break-out occurred after
                                            the I/O was complete
              ..1. ....      IORMULTI       X'20' This CP contains a
                                            multi-track CCW
              ...1 ....      IORWRKAL       X'10' WRKALLEG ON when I/O
                                            started
              .... 1...      IORPLV         X'08' MDC purge limits valid
              .... .1..      IORSCPQ        X'04' On state-change-pending
                                            queue
              .... ..1.      IORCIO         X'02' MDC I/O done on behalf of a
                                            guest channel program.
              .... ...1      IORUPVIO       X'01' Update virtual I/O request
                                            counters. Used by HCPIOV and
                                            HCPIOS to ensure that some
                                            counters are updated only once
                                            per guest start, regardless of
                                            the number of real starts done by
                                            CP.
    00CD  205 Bitstring    1 IORCRCLC       Used for enable completion for
                                            dialled ASCII terminals
    00CE  206 Bitstring    1 IORERMSG       ERROR MESSAGE CODE
              00000000       IORMREJ        000 COMMAND R  MESSAGE
              00000001       IORMIRQ        001 INTERVENTION REQUIRED MESSAGE
              00000002       IORMBUS        002 BUSOUT CHECK MESSAGE
              00000003       IORMEQP        003 EQUIPMENT CHECK MESSAGE
              00000004       IORMDTA        004 DATA CHECK MESSAGE
              00000005       IORMOVR        005 OVERRUN MESSAGE
              00000006       IORMTRK        006 TRACK CONDITION MESSAGE
              00000007       IORMSEK        007 SEEK CHECK MESSAGE
              00000008       IORMPRM        008 PERMANENT ERROR MESSAGE
              00000009       IORMTOV        009 TRACK OVERFLOW MESSAGE
              0000000A       IORMCNV        010 CONVERTOR CHECK MESSAGE
              0000000B       IORMCMP        011 COMPATIBILITY CHECK MESSAGE
              0000000C       IORMLDP        012 LOAD POINT MESSAGE
              0000000D       IORMPRT        013 PROTECTION CHECK MESSAGE
              0000000E       IORMNRF        014 NO RECORD FOUND MESSAGE
              0000000F       IORMEOC        015 END OF CYLINDER MESSAGE
              00000010       IORMBSN        016 BAD SENSE MESSAGE
              00000011       IORMUNK        017 UNKNOWN CCW MESSAGE
              00000012       IORMRCV        018 RECOVERY ERROR MESSAGE
              00000013       IORMPEB        019 PE BURST MESSAGE
              00000014       IORMCHN        020 CHANNEL ERROR MESSAGE
              00000015       IORMNDV        021 NO DEVICE MESSAGE
              00000016       IORMGAP        022 ERASE GAP ERROR MESSAGE
              00000017       IORMCTL        023 CONTROL CHECK MESSAGE
              00000018       IORMLDC        024 LOAD CHECK MESSAGE
              00000019       IORMFMT        025 FORMAT CHECK MESSAGE
              0000001A       IORDSEF        026 TAPE DATA SECURITY ERASE
                                            FAILED
              0000001B       IORMLST        027 LOST DATA MESSAGE
              0000001C       IORMTIM        028 TIME OUT MESSAGE
              0000001D       IORMPAR        029 PARITY CHECK MESSAGE
              0000001E       IORMUSP        030 UNIT SPECIFICATION
              0000001F       IORMDCK        031 DISPLAY CONTROL CHECK
              00000020       IORMOCK        032 OPERATION CHECK
              00000021       IORMEQPA       033 EQUPMENT CHECK WITH
                                            OPERATOR'S ACTION
              00000022       IORMUCS        034 UNUSUAL COMMAND SEQUENCE
              00000023       IORMOFF        035 DEVICE VARIED OFFLINE MESSAGE
              00000024       IORMWLB        036 DASD PACKED LABEL NOT MATCHED
              00000025       IORMELB        037 DASD LABEL CAN NOT BE READ
              00000026       IORMUNS        038 REPETITIVE UNSOLICITED DEVICE
                                            END
              00000027       IORMHDC        039 DASD POTENTIAL HEAD CRASH
              00000028       IORMSUP        040 COMMAND SUPPRESSION MESSSAGE
              0000002A       IORMINC        042 OPERATION INCOMPLETE
              00000057       IORMPEDP       087 MULTIPLE ENVIRONMENTAL DATA
                                            PRESENT
              0000005B       IORMCPRG       091 CHANNEL PROGRAM CHECK
              0000005F       IORMDLB        095 DASD LABEL DAMAGED
              000000EE       IORMBLFL       238 INDICATE BUFFER LOG FULL
              000000FE       IORMSGER       254 NON-CP (GUEST) ERROR
    00CF  207 Bitstring    1 IORRFLGE       I/O REQUEST EXTENDED FLAG
              1... ....      IORVMISF       X'80' CSE CHANNEL PROGRAM, DO NOT
                                            RETRY
              .1.. ....      IORFABST       X'40' FABRICATE A STORE
                                            SUBCHANNEL (STSCH)
              ..1. ....      IORDSO1        X'20' First CCW is a DSO.
              ...1 ....      IORIOA         X'10' IOASSIST INTERRUPT
              .... 1...      IORHLTED       X'08' The I/O was halted by a
                                            function internal to HCPCNS. The
                                            IRA for the I/O should go
                                            directly to HALTIO to process the
                                            I/O completion.
              .... .1..      IORVCAN        X'04' Virtual Cancel Request
                                            Occurred
    00D0  208 Bitstring   32 IORSDATA (0)   BUFFER FOR 32 BYTES OF SENSE DATA
    00D0  208 Bitstring    1 IORSDB00       BYTE 0 OF SENSE DATA
    00D1  209 Bitstring    1 IORSDB01       BYTE 1 OF SENSE DATA
    00D2  210 Bitstring    1 IORSDB02       BYTE 2 OF SENSE DATA
    00D3  211 Bitstring    1 IORSDB03       BYTE 3 OF SENSE DATA
    00D4  212 Bitstring    1 IORSDB04       BYTE 4 OF SENSE DATA
    00D5  213 Bitstring    1 IORSDB05       BYTE 5 OF SENSE DATA
    00D6  214 Bitstring    1 IORSDB06       BYTE 6 OF SENSE DATA
    00D7  215 Bitstring    1 IORSDB07       BYTE 7 OF SENSE DATA
    00D8  216 Bitstring    1 IORSDB08       BYTE 8 OF SENSE DATA
    00D9  217 Bitstring    1 IORSDB09       BYTE 9 OF SENSE DATA
    00DA  218 Bitstring    1 IORSDB10       BYTE 10 OF SENSE DATA
    00DB  219 Bitstring    1 IORSDB11       BYTE 11 OF SENSE DATA
    00DC  220 Bitstring    1 IORSDB12       BYTE 12 OF SENSE DATA
    00DD  221 Bitstring    1 IORSDB13       BYTE 13 OF SENSE DATA
    00DE  222 Bitstring    1 IORSDB14       BYTE 14 OF SENSE DATA
    00DF  223 Bitstring    1 IORSDB15       BYTE 15 OF SENSE DATA
    00E0  224 Bitstring    1 IORSDB16       BYTE 16 OF SENSE DATA
    00E1  225 Bitstring    1 IORSDB17       BYTE 17 OF SENSE DATA
    00E2  226 Bitstring    1 IORSDB18       BYTE 18 OF SENSE DATA
    00E3  227 Bitstring    1 IORSDB19       BYTE 19 OF SENSE DATA
    00E4  228 Bitstring    1 IORSDB20       BYTE 20 OF SENSE DATA
    00E5  229 Bitstring    1 IORSDB21       BYTE 21 OF SENSE DATA
    00E6  230 Bitstring    1 IORSDB22       BYTE 22 OF SENSE DATA
    00E7  231 Bitstring    1 IORSDB23       BYTE 23 OF SENSE DATA
    00E8  232 Bitstring    1 IORSDB24       BYTE 24 OF SENSE DATA
    00E9  233 Bitstring    1 IORSDB25       BYTE 25 OF SENSE DATA
    00EA  234 Bitstring    1 IORSDB26       BYTE 26 OF SENSE DATA
    00EB  235 Bitstring    1 IORSDB27       BYTE 27 OF SENSE DATA
    00EC  236 Bitstring    1 IORSDB28       BYTE 28 OF SENSE DATA
    00ED  237 Bitstring    1 IORSDB29       BYTE 29 OF SENSE DATA
    00EE  238 Bitstring    1 IORSDB30       BYTE 30 OF SENSE DATA
    00EF  239 Bitstring    1 IORSDB31       BYTE 31 OF SENSE DATA
    00F0  240 Bitstring    1 IOREFLGS       General I/O Flags
              1... ....      IORASSH        X'80' Assign owned by another
                                            guest
              .1.. ....      IORNSNS        X'40' Don't do sense on channel
                                            program chk
              ..1. ....      IORALOK        X'20' Assign lock is held
              ...1 ....      IOROPCT        X'10' Out-prioritized count
                                            already updated
    00F1  241 Bitstring    1 IORCPRI        Current priority of this I/O
                                            operation
    00F2  242 Bitstring    2 IOROPTI        Times this segment has been
                                            out-prioritized
    00F4  244 Bitstring    1 IOROPRI        Original priority of this I/O
                                            operation
    00F5  245 Bitstring    3 *              Reserved for IBM use
    00F8  248 Signed       4 IORLOWTA       Lowest track affected by I/O
    00FC  252 Signed       4 IORHITA        Highest track affected by I/O
    0100  256 Address      4 IORPURGE       MDC purge block chain
    0104  260 Address      4 IORMIPTR       POINTER TO BLOCKS USED FOR
                                            HANDLING MISSING INTERRUPT
                                            CONDITIONS (HCPMIHDR)
    0108  264 Address      4 IORSUSND       ADDRESS OF ROUTINE TO ALLOW A
                                            SUSPENDED CHANNEL PROGRAM TO
                                            COMPLETE NOTE! ROUTINE IS CALLED
                                            BY STATIC LINKAGE ONLY
    010C  268 Signed       4 IORCPTCA       POINTER TO CHANNEL PROGRAM
                                            TRANSLATION COMMUNICATION AREA
    0110  272 Signed       4 IORMSGID       Message id
    0114  276 Signed       2 IORETRSN       Reason code for IORETCOD
         Only information that must be preserved for redrive processing may be
         added following this block comment.
              00000116       IORRDRVB       * IO REDRIVE FIELD BEGINNING
    0116  278 Bitstring    1 IORDFLG2       DASD FLAG 2
              1... ....      IORLREST       X'80' LOCATE RECORD EXTENDED
                                            TRANSLATED
              .1.. ....      IORSMRST       X'40' SUSPEND MULTIPATH
                                            RECONNECTION WAS TRANSLATED
              ..1. ....      IORMBSET       X'20' 'PREPARE FOR READ SUBSYSTEM
                                            DATA' CCW WITH SUBORDER OF
                                            MESSAGE BUFFER
              ...1 ....      IORCASET       X'10' 'PERFORM SUBSYSTEM
                                            FUNCTION' CCW WITH ORDER OF
                                            'CANCEL ASYNCH. FUNCTION'
              .... 1...      IORSKSV        X'08' SEEK ARGUMENT STORED BY
                                            ARMPS FROM A LOCATE RECORD OR
                                            SEEK
              .... .1..      IORRISET       X'04' A Read IPL CCW was
                                            translated
              .... ..1.      IORFLSET       X'02' A Locate CCW was translated
              .... ...1      IORCONCP       X'01' It's a CONCOPY channel
                                            program
    0117  279 Bitstring    1 IORPFLAG       DASD flags for redrive
              1... ....      IORVISET       X'80' Virtual I/O counter has
                                            been updated
              .1.. ....      IORVWSET       X'40' Virtual write I/O counter
                                            updated
              ..1. ....      IORPXUSD       X'20' Prefix CCW was translated
                                            and IORPREFX has valid data
              ...1 ....      IORPXSIM       X'10' Prefix CCW was simulated
              .... 1...      IORCPREF       X'08' CP has turned on the
                                            prefetch bit
                                            (IOROFPI/IORUFPI,CSWPREF) in the
                                            ORB (IORORB) for this guest I/O
                                            request.
    0118  280 Bitstring    4 IORPREFX (0)   Prefix CCW bytes 0-3
    0118  280 Bitstring    1 IORPXFMT       Prefix Format byte
    0119  281 Bitstring    1 IORPXVLD       Prefix Validity byte
              1... ....      IORPXDXV       X'80' Define Ext data valid
              .1.. ....      IORPXTSV       X'40' Time Stamp valid
              ..1. ....      IORPXVBA       X'20' Verify base address
    011A  282 Bitstring    1 IORPXBAA       Base address
    011B  283 Bitstring    1 IORPXAUX       Prefix Auxiliary byte
              1... ....      IORPXSMR       X'80' Suspend Multipath Reconnect
    011C  284 Bitstring   32 IORDEXNT       Define extent data
    013C  316 Signed       2 IORDEXDC       Define extent Data Count
    013E  318 Bitstring    1 IORDEXFG       Define extent CCW flags
              ..1. ....      IORDEXSL       X'20' Define extent sili bit
    013F  319 Bitstring    1 *              Reserved for future IBM use
    0140  320 Bitstring    1 IORFMASK       SET FILE MASK DATA
         The IORDESET and IORGENDX bits in IORDFLG are used together to keep
         track of define extents within a guest channel program. Their meanings
         are defined as follows:
                   IORDESET   IORGENDX    MEANING
                      0          0        No define extent in
                                          channel program
                      0          1        (not defined)
                      1          0        Guest define extent in
                                          channel program
                      1          1        No guest define extent,
                                          only host-inserted one.
    0141  321 Bitstring    1 IORDFLG        DASD FLAG
              1... ....      IORFMSET       X'80' FILE MASK CCW WAS
                                            TRANSLATED
              .1.. ....      IORDESET       X'40' DEFINE EXTENT CCW WAS
                                            TRANSLATED
              ..1. ....      IORSCSET       X'20' SPACE COUNT CCW WAS
                                            TRANSLATED
              ...1 ....      IORLRSET       X'10' LOCATE RECORD WAS
                                            TRANSLATED
              .... 1...      IORRASET       X'08' RESET ALLEGIENCE WAS
                                            SIMULATED
              .... .1..      IORSKSET       X'04' SEEK WAS SIMULATED
              .... ..1.      IORGCCWP       X'02' IORBK CONTAINS GLOBAL CCW
              .... ...1      IORGENDX       X'01' DEFINE EXTENT CCW WAS
                                            GENERATED TO BYPASS CU CACHE
    0142  322 Bitstring    1 IORRLCMD       LAST EXECUTED REAL COMMAND CODE
    0143  323 Bitstring    1 IORLRCNT       COUNT OF CCWS TRANSLATED AFTER A
                                            Locate Record or Locate CCW
    0144  324 Bitstring    8 IORLCFBA (0)   Locate CCW parameter data
    0144  324 Bitstring   24 IORLREC        Locate Record Data
    015C  348 Bitstring    4 *              Reserved for IBM use
    0160  352 Bitstring    4 IORSVW3        Save ORB Word 3
              0000004E       IORRDRSZ       (*-IORRDRVB) IORRDRV FIELD SIZE
                                            IN BYTES
              00000116       IORRDRV        IORRDRVB,IORRDRSZ IO REDRIVE
                                            FIELD
              0000002D       IORSIZE        (*-IORBK+7)/8 IORBLOK BLOCK SIZE
         The following macro invocations are to ensure that an assembly error is
         generated if an increase, or decrease, in the size of the IORBK should
         have resulted in a change to the number of MVC or XC instructions
         generated by the HCPIORCC macro.
              00000040       IORMAX         512/8 The maximum number of
                                            doublewords that can be handled
                                            by two MVC or XC instructions.
              00000020       IORMIN         256/8 The minimum number of
                                            doublewords that can be handled
                                            by one MVC or XC instructions.
    0034   52 Signed       4 IORDEVIB (0)   SCHIB LOCATION FOR STSCH/MSCH
    0034   52 Bitstring   52 IORSCHIB       AREA TO COLLECT A SCHIB
    0088  136 Signed       4 IORSCMBK (0)   OVERLAY FOR MEASUREMENT INFO
    0088  136 Signed       2 IORNSSCH       INITIAL/DELTA SSCH OR RSCH COUNT
    008A  138 Signed       2 IORNSAMP       INITIAL/DELTA SAMPLE COUNT
    008C  140 Signed       4 IORCNTIM       INITIAL/DELTA DEVICE-CONNECT TIME
    0090  144 Signed       4 IORFPTIM       INITIAL/DELTA FUNCTION-PENDING
                                            TIME
    0094  148 Signed       4 IORDDTIM       INITIAL/DELTA DEVICE-DISCONNECT
                                            TIME
    0098  152 Signed       4 IORCQTIM       INITIAL/DELTA
                                            CONTROL-UNIT-QUEUEING TIME
    009C  156 Signed       4 IORDATIM       Device-Active-Only-Time
    00A0  160 Signed       4 *              RESERVED FOR FUTURE HARDWARE USE
    00A4  164 Signed       4 *              RESERVED FOR FUTURE HARDWARE USE
         Definitions of Reason Codes (IORETRSN) for different return codes
         (IORETCOD):
         IORFRESN - Fatal reason code (IORETCOD = 12) IORCRESN - Cancel reason
         code (IORETCOD = 20)
         NOTES : All non-zero reason codes should be unique regardless of the
         return code. This is because the return code may change without the
         reason code being updated, which could lead to a misinterpretation of
         the residual reason code if duplicates were defined.
    0114  276 Signed       2 IORFRESN       Reason code for IORETCOD = fatal
              00000000       IORFOK         0 Fatal with no special
                                            processing
              00000004       IORFSCP        4 Fatal due to
                                            state-change-pending
    0114  276 Signed       2 IORCRESN       Reason code for IORETCOD =
                                            cancelled
              00000000       IORCNLST       0 Cancelled after being started
              00000008       IORCNLSP       8 Cancelled before being started,
                                            i.e. the subchannel was start
                                            pending
    00AA  170 Bitstring    4 IORPSFA        PSF CCW ADDRESS
    0068  104 Bitstring    1 IORDKEY        TYPE 1 Subchannel CRQBK Storage
                                            Key
    0069  105 Bitstring    1 *              Reserve
    006A  106 Bitstring    2 IORDFASC (0)   FCTL (BIT 17-19) ACTL (BIT 20-26)
    006A  106 Bitstring    1 IORDFCTL
    006B  107 Bitstring    1 IORDACTL
    006C  108 Bitstring    4 IORDCRQ        CRQBK address
    0070  112 Bitstring    1 *
    0071  113 Bitstring    1 IORDSC         TYPE 1 Status Control
    0072  114 Bitstring    2 *

#### IORBK Storage Layout

    *** IORBK - I/O Request and Response Block
    *
    *     +---------------------------+---------------------------+
    *   0 |         IORUSER           |          IORIRA           |
    *     +---------------------------+---------------------------+
    *   8 |         IORFPNT           |         IORBPNT           |
    *     +------+------+------+------+---------------------------+
    *  10 |:QSTAT|//////|:SCHED|//////|///////////////////////////|
    *     +------+------+------+------+---------------------------+
    *  18 |         IORSAVE           |         IORPIOR           |
    *     +---------------------------+---------------------------+
    *  20 |         IORTASK           |         IORRDFND          |
    *     +-------------+-------------+-------------+-------------+
    *  28 |  IORTYGBL   |  IORTYLCL   |  IORECLVL   |  IORETCOD   |
    *     +-------------+-------------+-------------+-------------+
    *  30 |         IORVDEV           |         IORRDEV           |
    *     +------+------+------+------+---------------------------+
    *  38 |:OKEY |:OFPI |:OLPM |:OORB7|          IORCPA           |
    *     +------+------+------+------+---------------------------+
    *  40 |:PRTY |:OW3B1|:OW3B2|:OW3B3|///////////////////////////|
    *     +------+------+------+------+---------------------------+
    *  48 |///////////////////////////|///////////////////////////|
    *     +---------------------------+------+------+------+------+
    *  50 |///////////////////////////|:UKEY |:UFPI |:ULPM |:UORB7|
    *     +---------------------------+------+------+------+------+
    *  58 |///////////////////////////|         IORPOSCT          |
    *     +---------------------------+---------------------------+
    *  60 |         IORPOSSM          |///////////////////////////|
    *     +------+------+------+------+---------------------------+
    *  68 |:SKEY |:FPIZN|:FCTL |:ACTL |         IORCCWA           |
    *     +------+------+------+------+------+------+------+------+
    *  70 |:DVST |:SCST |   IORCNT    |IORECF|:LPUM |IORFVF|:TMSEQ|
    *     +------+------+------+------+------+------+------+------+
    *  78 |:ERWB0|:ERWB1|:ERWB2|:ERWB3|          IORFSA           |
    *     +------+------+------+------+---------------------------+
    *  80 |///////////////////////////|         IOR2DCCW          |
    *     +---------------------------+---------------------------+
    *  88 |                                                       |
    *     =                       IORXTLOG                        =
    *     |                                                       |
    *     +-------------+-------------+-------------+-------------+
    *  A8 |  IORECYL    |   IORBIN    |   IORCYL    |  IORHEAD    |
    *     +------+------+-------------+-------------+-------------+
    *  B0 |:CCWOC|//////|  IORSCNT    |///////////////////////////|
    *     +------+------+-------------+---------------------------+
    *  B8 |         IOREXTN           |///////////////////////////|
    *     +------+------+------+------+------+------+------+------+
    *  C0 |:IFLG |:RFLG |:CFLG |IORCMD|:STAT |:LMSGF|:DFLGS|:TYPE |
    *     +------+------+------+------+------+------+------+------+
    *  C8 |:XFLG |:ITFLG|:TFLG |:SWCC |:PFLG |:CRCLC|:ERMSG|:RFLGE|
    *     +------+------+------+------+------+------+------+------+
    *  D0 |:SDB00|:SDB01|:SDB02|:SDB03|:SDB04|:SDB05|:SDB06|:SDB07|
    *     +------+------+------+------+------+------+------+------+
    *  D8 |:SDB08|:SDB09|:SDB10|:SDB11|:SDB12|:SDB13|:SDB14|:SDB15|
    *     +------+------+------+------+------+------+------+------+
    *  E0 |:SDB16|:SDB17|:SDB18|:SDB19|:SDB20|:SDB21|:SDB22|:SDB23|
    *     +------+------+------+------+------+------+------+------+
    *  E8 |:SDB24|:SDB25|:SDB26|:SDB27|:SDB28|:SDB29|:SDB30|:SDB31|
    *     +------+------+------+------+------+------+------+------+
    *  F0 |:EFLGS|:CPRI |  IOROPTI    |:OPRI |////////////////////|
    *     +------+------+-------------+------+--------------------+
    *  F8 |         IORLOWTA          |         IORHITA           |
    *     +---------------------------+---------------------------+
    * 100 |         IORPURGE          |         IORMIPTR          |
    *     +---------------------------+---------------------------+
    * 108 |         IORSUSND          |         IORCPTCA          |
    *     +---------------------------+-------------+------+------+
    * 110 |         IORMSGID          |  IORETRSN   |:DFLG2|:PFLAG|
    *     +------+------+------+------+-------------+------+------+
    * 118 |:PXFMT|:PXVLD|:PXBAA|:PXAUX|                           |
    *     +------+------+------+------+                           |
    * 120 |                                                       |
    *     =                       IORDEXNT                        =
    *     |                           +-------------+------+------+
    * 138 |                           |  IORDEXDC   |:DEXFG|//////|
    *     +------+------+------+------+-------------+------+------+
    * 140 |:FMASK|:DFLG |:RLCMD|:LRCNT|                           |
    *     +------+------+------+------+                           |
    * 148 |                                                       |
    *     =                       IORLREC                         =
    *     |                           +---------------------------+
    * 158 |                           |///////////////////////////|
    *     +---------------------------+---------------------------+
    * 160 |         IORSVW3           | 164
    *     +---------------------------+
    *
    *** IORBK - I/O Request and Response Block

    *** Overlay for IORORB in IORBK
    *
    *                                 +---------------------------+
    *     ...                      34 |                           |
    *     +---------------------------+                           |
    *  38 |                                                       |
    *     =                       IORSCHIB                        =
    *     |                                                       |
    *     +-------------------------------------------------------+
    *  68
    *
    *** Overlay for IORORB in IORBK

    *** Overlay for IORXTLOG in IORBK
    *
    *     +-------------+-------------+---------------------------+
    *  88 |  IORNSSCH   |  IORNSAMP   |         IORCNTIM          |
    *     +-------------+-------------+---------------------------+
    *  90 |         IORFPTIM          |         IORDDTIM          |
    *     +---------------------------+---------------------------+
    *  98 |         IORCQTIM          |         IORDATIM          |
    *     +---------------------------+---------------------------+
    *  A0 |///////////////////////////|///////////////////////////|
    *     +---------------------------+---------------------------+
    *  A8
    *
    *** Overlay for IORXTLOG in IORBK

    *** Overlay for IORETRSN in IORBK
    *
    *                                 +-------------+
    * 110 ...                     114 |  IORFRESN   | 116
    *                                 +-------------+
    *
    *** Overlay for IORETRSN in IORBK

    *** Overlay for IORETRSN in IORBK
    *
    *                                 +-------------+
    * 110 ...                     114 |  IORCRESN   | 116
    *                                 +-------------+
    *
    *** Overlay for IORETRSN in IORBK

    *** Overlay for IORSBBCC in IORBK
    *
    *                   +---------------------------+
    *  A8 ...        AA |         IORPSFA           | AE
    *                   +---------------------------+
    *
    *** Overlay for IORSBBCC in IORBK

    *** Overlay for IORSCSW in IORBK
    *
    *     +------+------+------+------+---------------------------+
    *  68 |:DKEY |//////|:DFCTL|:DACTL|         IORDCRQ           |
    *     +------+------+------+------+---------------------------+
    *  70 |//////|IORDSC|/////////////| 74
    *     +------+------+-------------+
    *
    *** Overlay for IORSCSW in IORBK

#### IORBK Cross Reference

    Symbol         Dspl Value
    -------------- ---- -----
    IORABUSY       00C9 04
    IORACT         0010 10
    IORACTL        006B
    IORALOK        00F0 20
    IORASSH        00F0 80
    IORBIN         00AA
    IORBKOUT       00CC 80
    IORBPNT        000C
    IORCANCL       00C3 00000006
    IORCASC        006C
    IORCASET       0116 10
    IORCCTL        00C0
    IORCCWA        006C
    IORCCWOC       00B0
    IORCCWS        003C
    IORCCWTR       00C2 20
    IORCFLG        00C2
    IORCIO         00CC 02
    IORCLEAR       00C3 00000004
    IORCLSCR       00CA 80
    IORCMD         00C3
    IORCNLSP       0114 00000008
    IORCNLST       0114 00000000
    IORCNT         0072
    IORCNTIM       008C
    IORCONCP       0116 01
    IORCONT        00C0 80
    IORCOPY        00C2 40
    IORCPA         003C
    IORCPREF       0117 08
    IORCPRI        00F1
    IORCPSUS       00C8 80
    IORCPTCA       010C
    IORCQTIM       0098
    IORCRCLC       00CD
    IORCRESN       0114
    IORCSC         0070
    IORCSENQ       00CB 01
    IORCSFCM       00CB 80
    IORCSHLT       00CB 40
    IORCSNAV       00C4 08
    IORCSPCM       00CB 20
    IORCSTRC       00CB 10
    IORCSTRU       00CB 08
    IORCSWAD       00CB 02
    IORCSWBY       00CB 04
    IORCTRAN       00C6 10
    IORCUSER       00C7 000000FE
    IORCYL         00AC
    IORDACTL       006B
    IORDATIM       009C
    IORDCAN        00C6 08
    IORDCRQ        006C
    IORDCTI        0076
    IORDDTIM       0094
    IORDESET       0141 40
    IORDETCT       0074
    IORDEVIB       0034
    IORDEXDC       013C
    IORDEXFG       013E
    IORDEXNT       011C
    IORDEXSL       013E 20
    IORDFASC       006A
    IORDFCTL       006A
    IORDFLG        0141
    IORDFLGS       00C6
    IORDFLG2       0116
    IORDIAG        00C1 01
    IORDIA98       00C2 01
    IORDIFC        00C6 20
    IORDISAB       00C8 10
    IORDISPN       0010
    IORDKEY        0068
    IORDPOSD       00C0 02
    IORDQUNS       00C1 40
    IORDSC         0071
    IORDSEF        00CE 0000001A
    IORDSIC        00C6 40
    IORDSO1        00CF 20
    IORDVST        0070
    IORDWRIT       00C0 01
    IORD254        00C6 80
    IORECF         0074
    IORECLVL       002C
    IORECYL        00A8
    IOREFLGS       00F0
    IORERDAS       00C2 02
    IORERMSG       00CE
    IORERPCP       00C1 10
    IORERPEQ       00C1 20
    IORERPNW       00C1 08
    IORERW         0078
    IORERWB0       0078
    IORERWB1       0079
    IORERWB2       007A
    IORERWB3       007B
    IORETCOD       002E
    IORETRSN       0114
    IOREXTN        00B8
    IORFABST       00CF 40
    IORFATL        00C2 04
    IORFCAC        006A
    IORFCTL        006A
    IORFKBSY       00C9 80
    IORFLSET       0116 02
    IORFMASK       0140
    IORFMSET       0141 80
    IORFOK         0114 00000000
    IORFPIZN       0069
    IORFPNT        0008
    IORFPTIM       0090
    IORFRESN       0114
    IORFSA         007C
    IORFSA64       007C
    IORFSCP        0114 00000004
    IORFTRAN       00C2 08
    IORFULLR       0012 20
    IORFVF         0076
    IORGCCWP       0141 02
    IORGENDX       0141 01
    IORHALT        00C3 00000002
    IORHALTD       00C3 00000003
    IORHDVA        00C9 20
    IORHEAD        00AE
    IORHIPRI       0012 80
    IORHITA        00FC
    IORHLTED       00CF 08
    IORHSCH0       00C1 02
    IORIDONE       00CC 40
    IORIDTRQ       0012 01
    IORIFLG        00C0
    IORIOA         00CF 10
    IORIRA         0004
    IORIRB         0068
    IORIRLG        0074
    IORISAM        00C8 20
    IORITFLG       00C9
    IORLCFBA       0144
    IORLFATN       00C5 10
    IORLFPSF       00C5 80
    IORLFRAD       00C5 08
    IORLFRID       00C5 20
    IORLFRLD       00C5 40
    IORLFSSM       00C5 04
    IORLIFO        00C8 40
    IORLMSGF       00C5
    IORLOWTA       00F8
    IORLPUM        0075
    IORLRCNT       0143
    IORLREC        0144
    IORLREST       0116 80
    IORLRSET       0141 10
    IORMALPM       00C8 08
    IORMAX         0160 00000040
    IORMBLFL       00CE 000000EE
    IORMBSET       0116 20
    IORMBSN        00CE 00000010
    IORMBUPD       00C4 01
    IORMBUS        00CE 00000002
    IORMCHN        00CE 00000014
    IORMCMP        00CE 0000000B
    IORMCNV        00CE 0000000A
    IORMCPRG       00CE 0000005B
    IORMCTL        00CE 00000017
    IORMDCK        00CE 0000001F
    IORMDLB        00CE 0000005F
    IORMDLCK       00C0 40
    IORMDTA        00CE 00000004
    IORMELB        00CE 00000025
    IORMEOC        00CE 0000000F
    IORMEQP        00CE 00000003
    IORMEQPA       00CE 00000021
    IORMFMT        00CE 00000019
    IORMGAP        00CE 00000016
    IORMHDC        00CE 00000027
    IORMIN         0160 00000020
    IORMINC        00CE 0000002A
    IORMIPTR       0104
    IORMIRQ        00CE 00000001
    IORMLDC        00CE 00000018
    IORMLDP        00CE 0000000C
    IORMLST        00CE 0000001B
    IORMNDV        00CE 00000015
    IORMNRF        00CE 0000000E
    IORMOCK        00CE 00000020
    IORMODFY       00C3 00000005
    IORMOFF        00CE 00000023
    IORMOVR        00CE 00000005
    IORMPAR        00CE 0000001D
    IORMPEB        00CE 00000013
    IORMPEDP       00CE 00000057
    IORMPRM        00CE 00000008
    IORMPRT        00CE 0000000D
    IORMRCV        00CE 00000012
    IORMREJ        00CE 00000000
    IORMSEK        00CE 00000007
    IORMSGER       00CE 000000FE
    IORMSGID       0110
    IORMSUP        00CE 00000028
    IORMSWSP       00C8 02
    IORMTIM        00CE 0000001C
    IORMTOV        00CE 00000009
    IORMTRK        00CE 00000006
    IORMUCS        00CE 00000022
    IORMULTI       00CC 20
    IORMUNK        00CE 00000011
    IORMUNS        00CE 00000026
    IORMUSP        00CE 0000001E
    IORMWLB        00CE 00000024
    IORMXGCT       0028 00000801
    IORMXRCT       002C 0000000A
    IORNODQ        00C9 02
    IORNOERP       00C2 10
    IORNOLPM       00C8 04
    IORNSAMP       008A
    IORNSNS        00F0 40
    IORNSSCH       0088
    IOROCTL        0038
    IOROFPI        0039
    IOROKEY        0038
    IOROKF         0038
    IOROLPM        003A
    IOROORB7       003B
    IOROPCT        00F0 10
    IOROPRI        00F4
    IOROPTI        00F2
    IORORB         0034
    IOROWRD3       0040
    IOROW3B1       0041
    IOROW3B2       0042
    IOROW3B3       0043
    IORPFLAG       0117
    IORPFLG        00CC
    IORPIOR        001C
    IORPLV         00CC 08
    IORPOSCT       005C
    IORPOSSM       0060
    IORPREFX       0118
    IORPRTY        0040
    IORPSFA        00AA
    IORPURGE       0100
    IORPXAUX       011B
    IORPXBAA       011A
    IORPXDXV       0119 80
    IORPXFMT       0118
    IORPXSIM       0117 10
    IORPXSMR       011B 80
    IORPXTSV       0119 40
    IORPXUSD       0117 20
    IORPXVBA       0119 20
    IORPXVLD       0119
    IORQACTV       0010 40
    IORQANCH       0010 01
    IORQDSP        0010 20
    IORQQUED       0010 80
    IORQSTAT       0010
    IORRASET       0141 08
    IORRCDRV       002E 00000004
    IORRCEOF       002E 00000008
    IORRCFTL       002E 0000000C
    IORRCKIL       002E 00000010
    IORRCNCL       002E 00000014
    IORRCOK        002E 00000000
    IORRCTL        00C0
    IORRDEV        0034
    IORRDFND       0024
    IORRDRSZ       0160 0000004E
    IORRDRV        0160 00000116
    IORRDRVB       0114 00000116
    IORRESUM       00C0 08
    IORRFLG        00C1
    IORRFLGE       00CF
    IORRISET       0116 04
    IORRLCMD       0142
    IORSAVE        0018
    IORSBBCC       00AA
    IORSCCW        00B0
    IORSCHED       0012
    IORSCHIB       0034
    IORSCMBK       0088
    IORSCNT        00B2
    IORSCPQ        00CC 04
    IORSCSET       0141 20
    IORSCST        0071
    IORSCSW        0068
    IORSCTLS       0068
    IORSDATA       00D0
    IORSDB00       00D0
    IORSDB01       00D1
    IORSDB02       00D2
    IORSDB03       00D3
    IORSDB04       00D4
    IORSDB05       00D5
    IORSDB06       00D6
    IORSDB07       00D7
    IORSDB08       00D8
    IORSDB09       00D9
    IORSDB10       00DA
    IORSDB11       00DB
    IORSDB12       00DC
    IORSDB13       00DD
    IORSDB14       00DE
    IORSDB15       00DF
    IORSDB16       00E0
    IORSDB17       00E1
    IORSDB18       00E2
    IORSDB19       00E3
    IORSDB20       00E4
    IORSDB21       00E5
    IORSDB22       00E6
    IORSDB23       00E7
    IORSDB24       00E8
    IORSDB25       00E9
    IORSDB26       00EA
    IORSDB27       00EB
    IORSDB28       00EC
    IORSDB29       00ED
    IORSDB30       00EE
    IORSDB31       00EF
    IORSEEK        00AA
    IORSIFCC       00C4 02
    IORSIO         00C7 00000000
    IORSIZE        0160 0000002D
    IORSKCCW       00B0
    IORSKEY        0068
    IORSKSET       0141 04
    IORSKSV        0116 08
    IORSMRST       0116 40
    IORSNS         00C4 10
    IORSNSAC       00C4 40
    IORSNSIV       00C4 20
    IORSNSRQ       00C4 80
    IORSOURC       0075
    IORSPECL       00C7 000000FF
    IORSTART       00C3 00000001
    IORSTAT        00C4
    IORSTFLG       0070
    IORSUSND       0108
    IORSVW3        0160
    IORSWCC        00CB
    IORSYNCH       00C1 80
    IORTASK        0020
    IORTFLG        00CA
    IORTMSEQ       0077
    IORTRASH       00C9 10
    IORTRCCW       00C0 30
    IORTRPRT       00C0 10
    IORTRTRM       00C0 20
    IORTSS         00C9 40
    IORTYGBL       0028
    IORTYLCL       002A
    IORTYPE        00C7
    IORUCALL       0012 40
    IORUCTL        0054
    IORUFPI        0055
    IORUKEY        0054
    IORUKF         0054
    IORULPM        0056
    IORUNLOK       00C8 01
    IORUNSL        00C2 80
    IORUORB7       0057
    IORUPVIO       00CC 01
    IORUSER        0000
    IORUSRIO       00C1 04
    IORVCAN        00CF 04
    IORVDEV        0030
    IORVISET       0117 80
    IORVMISF       00CF 80
    IORVWSET       0117 40
    IORVXA         00C0 04
    IORWRKAL       00CC 10
    IORXFLG        00C8
    IORXOWDS       0040
    IORXTLOG       0088
    IOR2DCCW       0084
    IOR370AC       00C9 08
    IOR9C00        00C4 04

This information is based on z/VM V4R3.0. Last updated on 30 Apr 2002 at 17:05:49 EDT.
Copyright IBM Corporation, 1990, 2002