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

ITRBK

Prolog  

Control Block Contents  
   ITRBK DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  


ITRBK Prolog

 Name       : HCPITRBK
 Description: Host DAT Table Iterator Control Block
 DSECT      : ITRBK
 Function   : Contains information for a specific call to
              the Host DAT Table Iterator, HCPHDITR,
              particularly parameters and match criteria for
              the routine to be called.
 Located by : Local register usage in HCPHDITR and HCPHDITR's
              callers
 Created by : Callers of HCPHDITR
 Deleted by : Callers of HCPHDITR
 Serialized : Local task serialization (only the owning task has
              the address of the corresponding ITRBK), called
              routine serialization is the responsibility of
              HCPHDITR's caller.
 Comments   : Used to pass input parameters to HCPHDITR, and
              to pass output from the called routine back out
              to HCPHDITR's callers.  Also used to save HCPHDITR
              internal information for lower level iterator
              routines (iterator uses recursive descent to
              traverse multi-level host DAT tables; by saving
              the information in the ITRBK, we only have to
              pass one pointer down in a register, instead of
              passing everything in registers).

 

ITRBK Control Block Content


ITRBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      ITRBK          Host DAT Table Iterator Control Block
      HCPHDITR input parameter section.  To be filled in by
      callers of HCPHDITR.
0000    0 Signed       8 ITRSVADD       HCPHDITR input starting virtual
                                        address. If ITRLVPAG was not
                                        specified, PX and BX bits will be
                                        ignored, the address will be
                                        rounded down to a segment
                                        boundary by HCPHDITR. If ITRLVPAG
                                        was specified, only the BX bits
                                        will be ignored, the address will
                                        be rounded down to a 4K page
                                        boundary HCPHDITR.
0008    8 Signed       8 ITREVADD       HCPHDITR input ending virtual
                                        address. If ITRLVPAG was not
                                        specified, PX and BX bits will be
                                        ignored, will be rounded up to
                                        the highest address in the ending
                                        segment (that is, the next higher
                                        segment boundary address minus
                                        one) by HCPHDITR. If ITRLVPAG was
                                        specified, only the BX bits will
                                        be ignored, the address will be
                                        rounded up the highest address in
                                        the ending 4K page (that is, the
                                        next higher 4K page boundary
                                        address minus one) by HCPHDITR.
0010   16 Signed       8 ITRLEVEL (0)   Defines iteration target level.
                                        Similar in definition to TT bits
                                        in R*TE/STE, with the addition of
                                        an additional (mutually
                                        exclusive) bit to indicate page
                                        table level iteration.
          00000000       ITRLVSEG       X'00' ITRLVSEG Iterate at segment
                                        table level
          00000004       ITRLVRTT       X'04' ITRLVRTT Iterate at region
                                        third table level
          00000008       ITRLVRST       X'08' ITRLVRST Iterate at region
                                        second table level
          0000000C       ITRLVRFT       X'0C' ITRLVRFT Iterate at region
                                        first table level
          00000010       ITRLVPAG       X'10' ITRLVPAG Iterate at page
                                        table level
            Allowable ITRLEVEL values and corresponding target
            levels:
            x'0000000000000000' - ITRLVSEG:
                                  Iterate at segment table level
            x'0000000000000004' - ITRLVRTT:
                                  Iterate at region third table
                                  level
            x'0000000000000008' - ITRLVRST:
                                  Iterate at region second table
                                  level
            x'000000000000000C' - ITRLVRFT:
                                  Iterate at region first table
                                  level
            x'0000000000000010' - ITRLVPAG:
                                  Iterate at page table level
0010   16 Bitstring    1 * (7)          Reserved for IBM use
0017   23 Bitstring    1 ITRLEVB7       Defines iteration target level:
0018   24 Signed       8 ITRCRMBZ       HCPHDITR table entry match
                                        criteria "Must Be Zero" bit mask
                                        (if both ITROPTE and ITROPCRI
                                        were specified). Bits which are
                                        one in this mask must be zero in
                                        a table entry for the target
                                        routine to be called for that
                                        table entry.
0020   32 Signed       8 ITRCRMBO       HCPHDITR table entry match
                                        criteria "Must Be Ones" bit mask
                                        (if both ITROPTE and ITROPCRI
                                        were specified). Bits which are
                                        one in this mask must also be one
                                        in a table entry for the target
                                        routine to be called for that
                                        table entry.
0028   40 Bitstring    1 ITROPTS        Option flags for HCPHDITR
          1... ....      ITROPTE        X'80' ITROPTE Iterate on table
                                        entries at the specified level.
                                        Target routine is called once per
                                        table found at the specified
                                        level which represents virtual
                                        addresses within the input
                                        virtual address range; the table
                                        entry address is passed as an
                                        argument to the target routine.
          .1.. ....      ITROPTBL       X'40' ITROPTBL Iterate on tables
                                        at the specified table level.
                                        Target routine is called once per
                                        table found at the specified
                                        level which represents virtual
                                        addresses within the input
                                        virtual address range; the table
                                        designation is passed as an
                                        argument to the target routine.
                                        Notes : One of ITROPTE or
                                        ITROPTBL *MUST* be specified,
                                        although they are mutually
                                        exclusive. Calls with both or
                                        neither set will result in an
                                        ABEND.
          ..1. ....      ITROPPTV       X'20' ITROPPTV Only has meaning
                                        if ITRLEVEL is set to indicate
                                        iteration at the page table
                                        level, or if ITRLEVEL is set to
                                        indicate iteration at the segment
                                        table level with ITROPTE set to
                                        indicate iteration at the segment
                                        table entry level. ITROPPTV set
                                        indicates that any page tables
                                        which have been paged out should
                                        be validated during processing.
          ...1 ....      ITROPCRI       X'10' ITROPCRI May only be set if
                                        ITRITTE is also set, to indicate
                                        iteration on table entries. The
                                        ITRCRMBZ and ITRCRMBO inputs
                                        specify table entry match
                                        criteria: ITRCRMBZ is a bit mask
                                        specifying bits which much be
                                        zero in a target table entry for
                                        the entry to be considered a
                                        match (bits which are one in
                                        ITRCRMBZ must be zero in a target
                                        table entry for it to be
                                        considered a match). ITRCRMBO is
                                        a bit mask specifying bits which
                                        much be ones in a target table
                                        entry for the entry to be
                                        considered a match (bits which
                                        are one in ITRCRMBO must also be
                                        one in a target table entry for
                                        it to be considered a match). The
                                        target routine is called only if
                                        the table entry matches the
                                        criteria.
0029   41 Bitstring    1 * (3)          reserved for IBM use
002C   44 Signed       4 ITRTARG        Address of target routine to be
                                        called for host DAT tables (or
                                        entries) which match the
                                        specified input criteria. Routine
                                        must have attribute SAVE=DYNamic.
0030   48 Bitstring    1 * (4)          reserved for IBM use
0034   52 Signed       4 ITRTROPT       Target routine R2 parameter
                                        options. Will be passed to the
                                        target routine in R2.
0038   56 Signed       4 ITRTRTOK       Target routine parameter token.
                                        Will be passed to the called
                                        routine in R3. If parameters are
                                        to be passed to, or back from,
                                        the called routine, this field
                                        may be used to pass a 32 bit
                                        parameter value, or may be used
                                        to pass the address of a
                                        parameter data area (obtaining,
                                        releasing, and serializing such a
                                        data area is entirely the
                                        responsibility of the caller and
                                        the called routine, not the
                                        iterator).
003C   60 Signed       4 ITRASCBK       Address of ASCBK from original
                                        HCPHDITR R8 input.
0040   64 Signed       4 *              Reserved for IBM use
      HCPHDITR output section.  Contains HCPHDITR processing
      information for return to HCPHDITR's caller.
0048   72 Signed       8 ITRCALCT       Running count of calls made to
                                        the target routine by HCPHDITR.
                                        Is only incremented, is not
                                        initialized to 0 by HCPHDITR,
                                        allowing the caller to use it as
                                        a running count of calls to the
                                        target routine across multiple
                                        invocations of HCPHDITR.
      HCPHDITR internal usage section.  Should not be used by
      callers of HCPHDITR.
0050   80 Bitstring    1 ITRSTAT        Iterator status byte
          1... ....      TRGRTERR       X'80' TRGRTERR The target routine
                                        returned a non-zero condition
                                        code or R15 return code
0051   81 Bitstring    1 * (7)          Reserved for IBM use
0058   88 Signed       4 ITRTRGCC       Target routine condition code
                                        (saved in IPM/SPM format)
005C   92 Signed       4 ITRTRGRC       Target routine R15 return code
      End of ITRBK
0060   96 Signed       4 ITR$END (0)    End of ITRBK control block
          00000060       ITRLEN         *-ITRBK Length of ITRBK in bytes
          0000000C       ITRSIZE        (ITRLEN+7)/8 Size of ITRBK in
                                        doublewords

 

ITRBK Storage Layout

          
*** ITRBK - Host DAT Table Iterator Control Block
*
*     +-------------------------------------------------------+
*   0 |                       ITRSVADD                        |
*     +-------------------------------------------------------+
*   8 |                       ITREVADD                        |
*     +------------------------------------------------+------+
*  10 |////////////////////////////////////////////////|:LEVB7|
*     +------------------------------------------------+------+
*  18 |                       ITRCRMBZ                        |
*     +-------------------------------------------------------+
*  20 |                       ITRCRMBO                        |
*     +------+--------------------+---------------------------+
*  28 |:OPTS |////////////////////|         ITRTARG           |
*     +------+--------------------+---------------------------+
*  30 |///////////////////////////|         ITRTROPT          |
*     +---------------------------+---------------------------+
*  38 |         ITRTRTOK          |         ITRASCBK          |
*     +---------------------------+---------------------------+
*  40 |///////////////////////////|///////////////////////////|
*     +---------------------------+---------------------------+
*  48 |                       ITRCALCT                        |
*     +------+------------------------------------------------+
*  50 |:STAT |////////////////////////////////////////////////|
*     +------+--------------------+---------------------------+
*  58 |         ITRTRGCC          |         ITRTRGRC          |
*     +---------------------------+---------------------------+
*
*** ITRBK - Host DAT Table Iterator Control Block

 

ITRBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
ITR$END        0060
ITRASCBK       003C
ITRCALCT       0048
ITRCRMBO       0020
ITRCRMBZ       0018
ITREVADD       0008
ITRLEN         0060 00000060
ITRLEVB7       0017
ITRLEVEL       0010
ITRLVPAG       0010 00000010
ITRLVRFT       0010 0000000C
ITRLVRST       0010 00000008
ITRLVRTT       0010 00000004
ITRLVSEG       0010 00000000
ITROPCRI       0028 10
ITROPPTV       0028 20
ITROPTBL       0028 40
ITROPTE        0028 80
ITROPTS        0028
ITRSIZE        0060 0000000C
ITRSTAT        0050
ITRSVADD       0000
ITRTARG        002C
ITRTRGCC       0058
ITRTRGRC       005C
ITRTROPT       0034
ITRTRTOK       0038
TRGRTERR       0050 80

This information is based on z/VM V5R4.0. Last updated on 18 Feb 2010 at 03:46:59 EDT.
Copyright IBM Corporation, 1990, 2009