LRDA Back to Index page
 
Prolog 
Control Block Contents 
   LRDA DSECT
   LRDXILRE DSECT
Storage Layout 
Cross Reference (Contains links to field and bit definitions)
Programming Interface Information:
This information is NOT intended to be
used as Programming Interfaces of z/VM.


  LRDA Prolog Top of page
 
 NAME       : HCPLRDA
 DESCRIPTION: Locate Record (Extended) data area
 DSECT      : LRDA
 FUNCTION   : Maps the contents of the Locate Record
              (Extended) data area.
 LOCATED BY :
              HCCWADDR - The Locate Record CCW data address field
              contains the address of the locate
              record data area.
 CREATED BY :
              Storage for this control block cannot be
              specifically allocated/deallocated using
              HCPGETST/HCPRELST.
              Paging I/O manager -
              The data area resides in the HCPPIOBK which
              is allocated by HCPRDA.
              Track cache manager -
              Data area is part of a larger free storage
              area used to build ECKD channel programs
              which is allocated in modules HCPFMU/HCPFMP.
 DELETED BY :
              Storage for this control block cannot be
              specifically allocated/deallocated using
              HCPGETST/HCPRELST.
              Paging I/O manager -
              The data area resides in the HCPPIOBK which
              is allocated by HCPRDD.
              Track cache manager -
              Data area is part of a larger free storage
              area used to build ECKD channel programs
              which is deallocated in modules HCPFMU/HCPFMP.
 SERIALIZED :
              Paging I/O manager -
              EXPLCKFG - The paging I/O manager uses the exposure
              block lock to serialize this data area.
              Track cache manager -
              TCMTSLK  - Track cache lock
 RELOCATION CONSIDERATIONS : None
 COMMENTS   :
              Paging I/O manager -
              The Locate Record data area resides in the
              HCPPIOBK. Each Locate Record CCW address field
              contains the address of the Locate Record data
              area within that PIOBK.
              Track cache manager -
              None
 
 
  LRDA Control Block Content Top of page
 

 LRDA DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure LRDA Locate Record (Extended) data area 0000 0 Bitstring 16 LRDAREA (0) Locate record data area Byte 0 (Operation byte) Although defined as BITs, the contents of the operation byte are, architecturally, multiple codes. 0000 0 Bitstring 1 LRDOP Operation byte 11.. .... LRDOR X'C0' LRDOR Operation byte, bits 0 and 1 ------- Codes for use with LRDOR .... .... LRDORCA X'00' LRDORCA Orient on count area .1.. .... LRDORHA X'40' LRDORHA Orient on home address 1... .... LRDORDA X'80' LRDORDA Orient on data area 11.. .... LRDORIX X'C0' LRDORIX Orient on index ------- ..11 1111 LRDOOC X'3F' Operation byte, bits 2 through 7 ------- Codes for use with LRDOOC .... .... LRDOCOR X'00' Orient .... ...1 LRDOCWD X'01' Write data .... ..11 LRDOCFW X'03' Format write .... .11. LRDOCRD X'06' Read data .... 1.11 LRDOCWT X'0B' Write track .... 11.. LRDOCRT X'0C' Read tracks ...1 .11. LRDOCR X'16' Read ------- Byte 1 (Auxiliary byte) 0001 1 Bitstring 1 LRDAUX Auxiliary byte 1... .... LRDAVTLF X'80' LRDAVTLF Validate transfer length factor .1.. .... LRDATLFS X'40' LRDATLFS (TM) Transfer Length Factor Scope ..1. .... LRDICCWV X'20' LRDICCWV (TM) Imbedded CCW Op Code Valid ...1 .... LRDCBTMW X'10' LRDCBTMW (TM) CRC on track boundary (WRITE) .... 1... LRDCBTMR X'08' LRDCBTMR (TM) CRC on TCW boundary (READ) .... .1.. LRDILRCV X'04' LRDILRCV (TM) Imbedded Loc Record Count is valid .... ...1 LRDARCS X'01' LRDARCS Read count suffix Byte 2 (Zeros -- Locate Record) Byte 2 (Imbedded CCW op code -- Loc Rec Extended) 0002 2 Bitstring 1 LRDZEROS Must be zeros .... ..1. LRDICCW LRDZEROS LRDICCW (TM) Imbedded CCW Op Code (LRE only) Byte 3 (Record count) 0003 3 Bitstring 1 LRDRECCT Record count Bytes 4 through 7 (Seek address) 0004 4 Bitstring 4 LRDSEEK (0) Seek address (CCHH) 0004 4 Bitstring 2 LRDSCC CC of CCHH 0006 6 Bitstring 2 LRDSHH HH of CCHH Bytes 8 through 12 (Search argument) 0008 8 Bitstring 5 LRDSRCH (0) Search argument (CCHHR) 0008 8 Bitstring 4 LRDRCCCH (0) Cylinder and head (CCCCcccH) 0008 8 Bitstring 2 LRDRCC CC of CCHHR 000A 10 Bitstring 2 LRDRHH HH of CCHHR 000C 12 Bitstring 1 LRDRR R of CCHHR Byte 13 (Sector number) 000D 13 Bitstring 1 LRDSECT Sector number Bytes 14 and 15 (Transfer length factor) 000E 14 Bitstring 2 LRDTLF Transfer length factor Length equates 00000010 LRDBSIZE *-LRDAREA Size of LRDA in bytes 00000002 LRDSIZE ((*-LRDAREA)+7)/8 Size of LRDA in DWs Bytes 16 through 19 (Locate Record Extended) For Transport Mode support 0010 16 Bitstring 1 LRDXILRC (TM) Imbedded Locate Record Count 0011 17 Bitstring 1 LRDXOP (TM) Extended Operation Byte ..1. ..11 LRDXUT X'23' LRDXUT Update Tracks 0012 18 Bitstring 2 LRDXPLEN (TM) Extended Parameter Length Bytes 20-nn (Locate Record Extended Parameters) For Transport Mode support 0014 20 Bitstring 1 LRDXPARM (0) (TM) Extended Parameters 00000014 LRDXBSZ *-LRDAREA Size of Extended LRDA in bytes 00000003 LRDXDSZ (LRDXBSZ+7)/8 Size of Extended LRDA in DWs DSECT for mapping each Imbedded Locate Record entry For Transport Mode support
 LRDXILRE DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure LRDXILRE Locate Record (Extended) data area 0000 0 Bitstring 5 LRDXSRCH (0) Search argument (CCHHR) 0000 0 Bitstring 4 LRDXCCCH (0) Cylinder and head (CCCCcccH) 0000 0 Bitstring 2 LRDXCC CC 0002 2 Bitstring 2 LRDXHH CC 0004 4 Bitstring 1 LRDXR R 0005 5 Bitstring 1 LRDXCT Count 0006 6 Bitstring 2 LRDXTLF Transfer length factor 00000008 LRDXILRB *-LRDXILRE Byte size of Imbedded LR entry
 
 
  LRDA Storage Layout Top of page
 
          
*** LRDA - Locate Record (Extended) data area
*
*     +------+------+------+------+-------------+-------------+
*   0 |LRDOP |LRDAUX|:ZEROS|:RECCT|   LRDSCC    |   LRDSHH    |
*     +------+------+------+------+------+------+-------------+
*   8 |   LRDRCC    |   LRDRHH    |LRDRR |:SECT |   LRDTLF    |
*     +------+------+-------------+------+------+-------------+
*  10 |:XILRC|LRDXOP|  LRDXPLEN   |
*     +------+------+-------------+
*
*** LRDA - Locate Record (Extended) data area
          
*** LRDXILRE - Locate Record (Extended) data area
*
*     +-------------+-------------+------+------+-------------+
*   0 |   LRDXCC    |   LRDXHH    |LRDXR |LRDXCT|  LRDXTLF    |
*     +-------------+-------------+------+------+-------------+
*   8
*
*** LRDXILRE - Locate Record (Extended) data area
 
 
  LRDA Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
LRDARCS        0001 01
LRDAREA        0000
LRDATLFS       0001 40
LRDAUX         0001
LRDAVTLF       0001 80
LRDBSIZE       000E 00000010
LRDCBTMR       0001 08
LRDCBTMW       0001 10
LRDICCW        0002 02
LRDICCWV       0001 20
LRDILRCV       0001 04
LRDOCFW        0000 03
LRDOCOR        0000 00
LRDOCR         0000 16
LRDOCRD        0000 06
LRDOCRT        0000 0C
LRDOCWD        0000 01
LRDOCWT        0000 0B
LRDOOC         0000 3F
LRDOP          0000
LRDOR          0000 C0
LRDORCA        0000 00
LRDORDA        0000 80
LRDORHA        0000 40
LRDORIX        0000 C0
LRDRCC         0008
LRDRCCCH       0008
LRDRECCT       0003
LRDRHH         000A
LRDRR          000C
LRDSCC         0004
LRDSECT        000D
LRDSEEK        0004
LRDSHH         0006
LRDSIZE        000E 00000002
LRDSRCH        0008
LRDTLF         000E
LRDXBSZ        0014 00000014
LRDXCC         0000
LRDXCCCH       0000
LRDXCT         0005
LRDXDSZ        0014 00000003
LRDXHH         0002
LRDXILRB       0006 00000008
LRDXILRC       0010
LRDXOP         0011
LRDXPARM       0014
LRDXPLEN       0012
LRDXR          0004
LRDXSRCH       0000
LRDXTLF        0006
LRDXUT         0011 23
LRDZEROS       0002
 
This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:29:01 EDT.
Copyright IBM Corporation, 1990, 2020