Programming Interface Information:
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ITRBK
Control Block Contents
ITRBK DSECT
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' Iterate at segment table level 00000004 ITRLVRTT X'04' Iterate at region third table level 00000008 ITRLVRST X'08' Iterate at region second table level 0000000C ITRLVRFT X'0C' Iterate at region first table level 0000000C ITRLVPAG X'0C' 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 zero in this mask must also 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' 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' 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' May only be set if ITRLEVEL is set to indicate iteration at the page table level. If set, indicates that any page tables which have been paged out should be validated during processing. ...1 .... ITROPCRI X'10' 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 zero in ITRCRMBZ must also 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 attributes RESident, DYNamic, LONGreg, and can be MP (the default) or non-MP (if ITRTRNMP is set in ITRTRATT) 0030 48 Bitstring 1 ITRTRATT Target routine attribute flags 1... .... ITRTRNMP X'80' Target routine is non-MP (master only). If not set, the target routine is assumed to be MP. 0031 49 Bitstring 1 * (3) 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 R1. 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' 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$END (0) End of ITRBK control block 00000060 ITRLEN *-ITRBK Length of ITRBK in bytes 0000000C ITRSIZE (ITRLEN+7)/8 Size of ITRBK in doublewords
ITRBK Storage Layout
*** ITRBK - Host DAT Table Iterator Control Block * * +-------------------------------------------------------+ * 0 | ITRSVADD | * +-------------------------------------------------------+ * 8 | ITREVADD | * +------------------------------------------------+------+ * 10 |////////////////////////////////////////////////|:LEVB7| * +------------------------------------------------+------+ * 18 | ITRCRMBZ | * +-------------------------------------------------------+ * 20 | ITRCRMBO | * +------+--------------------+---------------------------+ * 28 |:OPTS |////////////////////| ITRTARG | * +------+--------------------+---------------------------+ * 30 |:TRATT|////////////////////| ITRTROPT | * +------+--------------------+---------------------------+ * 38 | ITRTRTOK | ITRASCBK | * +---------------------------+---------------------------+ * 40 |///////////////////////////|///////////////////////////| * +---------------------------+---------------------------+ * 48 | ITRCALCT | * +------+------------------------------------------------+ * 50 |:STAT |////////////////////////////////////////////////| * +------+--------------------+---------------------------+ * 58 | ITRTRGCC | ITRTRGRC | * +---------------------------+---------------------------+ * *** ITRBK - Host DAT Table Iterator Control Block
ITRBK Cross Reference
Symbol Dspl Value -------------- ---- ----- ITR$END 0060 ITRASCBK 003C ITRCALCT 0048 ITRCRMBO 0020 ITRCRMBZ 0018 ITREVADD 0008 ITRLEN 0060 00000060 ITRLEVB7 0017 ITRLEVEL 0010 ITRLVPAG 0010 0000000C 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 ITRTRATT 0030 ITRTRGCC 0058 ITRTRGRC 005C ITRTRNMP 0030 80 ITRTROPT 0034 ITRTRTOK 0038 TRGRTERR 0050 80
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