LWKBK Back to Index page
 
Prolog 
Control Block Contents 
   LWKBK DSECT
   LWKCCWPG 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.


  LWKBK Prolog Top of page
 
 NAME       : HCPLWKBK
 DESCRIPTION: ISFC Link Work management structure
 DSECT      : LWKBK
 FUNCTION   :
              This block is used to manage a unit of work for
              an ISFC link.
 LOCATED BY :
              A given LWKBK belongs to a specific link work queue
              at any point in time.
 CREATED BY :
              ISFC Link Management.
 DELETED BY :
              ISFC Link Management.
 SERIALIZED :
              Each LWKBK instance is owned by a single task.
              The serialization that protects the associated
              link or device also protects this LWKBK.
 RELOCATION CONSIDERATIONS : None
 NOTES      :
              The LWKBK logically contains several distinct
              areas associated with a link data transfer.
 
 
  LWKBK Control Block Content Top of page
 

 LWKBK DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure LWKBK ISFC Link Work management structure LWKFPNT and LWKBPNT implement a double-linked, circular chain with the following anchors: - LNKWRK_PENDING used in HCPKCLCU. - LNKTX_PENDING used in HCPKCWDS, HCPKCWDC, and HCPKCWSD. - LNKRX_QUEUE used in HCPKCW's LNKRX_INSERT and LNKRX_REMOVE subroutines. LWKFPNT implements a single-linked chain with the following anchor: - KCMLWKBK used in HCPKCL's PUT_AVAIL and GET_AVAIL subroutines. 0000 0 Address 4 LWKFPNT Pointer to next LWKBK area 0004 4 Address 4 LWKBPNT Pointer to prev LWKBK area 0008 8 Bitstring 1 LWKTYPE Type of work page 00000001 LWK_WRITE 1 LWK_WRITE - Write Task 00000002 LWK_READ 2 LWK_READ - Read Task 0009 9 Bitstring 1 LWKSTAT Status of this work element 00000000 LWK_EMPTY 0 LWK_EMPTY - Empty (unused) 00000001 LWK_OPEN 1 LWK_OPEN - Open for new data 00000002 LWK_READY 2 LWK_READY - Ready for processing 00000003 LWK_ACTIVE 3 LWK_ACTIVE - I/O Active on LWK_LDVBK 00000004 LWK_WAIT 4 LWK_WAIT - Waiting for data exchange 00000005 LWK_POST 5 LWK_POST - Post processing after I/O 000A 10 Bitstring 1 LWKMODE Data Transfer Mode 00000001 LWK_SYNC 1 LWK_SYNC - Synchronous mode 00000002 LWK_ASYNC 2 LWK_ASYNC - Asynchronous mode 00000003 LWK_IMBED 3 LWK_IMBED - Imbedded (Synchronous) mode 000B 11 Bitstring 1 LWKTX_FLAG Send Processing flags 1... .... LWKTX_RESEND X'80' LWKTX_RESEND Resend LWKBK following error 000C 12 Bitstring 1 LWKRX_FLAG Receive Processing flags 1... .... LWKRX_STGREQ X'80' LWKRX_STGREQ Storage request in progress 000D 13 Bitstring 1 LWKSTGMS Storage Management status 000E 14 Signed 2 LWKSEQNO TX Sequence Number 0010 16 Address 4 LWKLNKBK Pointer to Link structure 0014 20 Address 4 LWKLDVBK Pointer to Device structure 0018 24 Address 8 LWK_CTLPAGE Pointer (HA) to CTL page 0020 32 Address 8 LWK_CTLNXT Pointer to Next CTL slot 0028 40 Address 8 LWK_CTLSTOP Pointer to End of CTL page 0030 48 Address 4 LWK_CCWPAGE Pointer (HL) to CCW page 0034 52 Bitstring 1 LWK_CCWFLAG CCW Processing flags 1... .... LWK_CCWOPEN X'80' LWK_CCWOPEN LWK_CCWNXT->CCW is open .1.. .... LWK_CCW4KFRM X'40' LWK_CCW4KFRM Last fragment was 4KB 0035 53 Bitstring 1 LWK_PRIORITY Priority (0=Low; 7=High) 0036 54 Signed 2 LWK_CCWCNT CCWs used for client data 0038 56 Address 4 LWK_CCWNXT Pointer to Next CCW slot 003C 60 Address 4 LWK_CCWSTOP Pointer to End of CCW area 0040 64 Address 4 LWK_IDANXT Pointer to Next IDAW slot 0044 68 Address 4 LWK_IDASTOP Pointer to End of IDAW area 0048 72 Dbl-Word 8 LWK_CCW1 CCW(1) may be Write (TXCTL) 0050 80 Dbl-Word 8 LWK_CCW2 CCW(2) may be Read (RXCTL) 0058 88 Dbl-Word 8 LWK_CCW3 CCW(3) may be NOP 0060 96 Bitstring 16 LWK_BUFFER Local buffer for ctl msgs 0070 112 Dbl-Word 8 LWKTOD TOD when TX LWKBK is enqueued or when RX LWKBK is received 0078 120 Address 8 LWKFRMAD HA pointer to available frames 0080 128 Signed 4 LWKBYTES Number of bytes installed (This includes CTLMAP plus the sum of all MBHMSGLN values) 0084 132 Signed 4 LWKREQUE Count of times re-queued 0088 136 Bitstring 8 LWKLINST Copy of LNKLINST for validation 0090 144 Signed 4 LWKREFCT Reference counter (CS updates) 0094 148 Signed 4 LWKMBHCT Number of messages installed The value of LWK_MAXMBH for DATAMAP is 64 0098 152 Address 4 LWKMBHBK (4) Array of pointers to MBHBK 00000198 LWKBKLN *-LWKBK Length of LWKBK in bytes 00000033 LWKBKSZ (LWKBKLN+7)/8 Size of LWKBK in doublewords LWKCCWPG - CCW Page (associated with LWKBK)
 LWKCCWPG DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure LWKCCWPG ISFC Link Work management structure 0000 0 Character 8 LWKCCW_TAG Eye Catcher (CCWPAGE:) 0008 8 Dbl-Word 8 LWKCCW1 First CCW (Read/Write MAP) The value of LWK_MAXCCW for DATAMAP is 250 0010 16 Dbl-Word 8 LWKCCW (250) CCW array for raw data frames 07E0 2016 Dbl-Word 8 LWKEOD Reserve space for EOD exchange 07E8 2024 Dbl-Word 8 LWKTIC Reserve space for TIC The value of LWK_MAXIDAW for DATAMAP is 250 07F0 2032 Address 8 LWKIDAL (250) IDAW list / MIDAW list Set limits for this transmission unit. 00000040 LWK_MAXMBH 64 Limit number of msgs per unit 000000FA LWK_MAXCCW 250 Limit CCWs per unit 000000FA LWK_MAXIDAW 250 Limit IDAWs per unit
 
 
  LWKBK Storage Layout Top of page
 
          
*** LWKBK - ISFC Link Work management structure
*
*     +---------------------------+---------------------------+
*   0 |         LWKFPNT           |         LWKBPNT           |
*     +------+------+------+------+------+------+-------------+
*   8 |:TYPE |:STAT |:MODE |(00B) |(00C) |:STGMS|  LWKSEQNO   |
*     +------+------+------+------+------+------+-------------+
*  10 |         LWKLNKBK          |         LWKLDVBK          |
*     +---------------------------+---------------------------+
*  18 |                     LWK_CTLPAGE                       |
*     +-------------------------------------------------------+
*  20 |                      LWK_CTLNXT                       |
*     +-------------------------------------------------------+
*  28 |                     LWK_CTLSTOP                       |
*     +---------------------------+------+------+-------------+
*  30 |       LWK_CCWPAGE         |(034) |(035) | LWK_CCWCNT  |
*     +---------------------------+------+------+-------------+
*  38 |        LWK_CCWNXT         |       LWK_CCWSTOP         |
*     +---------------------------+---------------------------+
*  40 |        LWK_IDANXT         |       LWK_IDASTOP         |
*     +---------------------------+---------------------------+
*  48 |                       LWK_CCW1                        |
*     +-------------------------------------------------------+
*  50 |                       LWK_CCW2                        |
*     +-------------------------------------------------------+
*  58 |                       LWK_CCW3                        |
*     +-------------------------------------------------------+
*  60 |                      LWK_BUFFER                       |
*     |                                                       |
*     +-------------------------------------------------------+
*  70 |                        LWKTOD                         |
*     +-------------------------------------------------------+
*  78 |                       LWKFRMAD                        |
*     +---------------------------+---------------------------+
*  80 |         LWKBYTES          |         LWKREQUE          |
*     +---------------------------+---------------------------+
*  88 |                       LWKLINST                        |
*     +---------------------------+---------------------------+
*  90 |         LWKREFCT          |         LWKMBHCT          |
*     +---------------------------+---------------------------+
*  98 |                       LWKMBHBK                        |
*     |                                                       |
*     +-------------------------------------------------------+
*  A8
*
*** LWKBK - ISFC Link Work management structure
          
*** LWKCCWPG - ISFC Link Work management structure
*
*     +-------------------------------------------------------+
*   0 |                      LWKCCW_TAG                       |
*     +-------------------------------------------------------+
*   8 |                       LWKCCW1                         |
*     +-------------------------------------------------------+
*  10 |                                                       |
*     =                        LWKCCW                         =
*     |                                                       |
*     +-------------------------------------------------------+
* 7E0 |                        LWKEOD                         |
*     +-------------------------------------------------------+
* 7E8 |                        LWKTIC                         |
*     +-------------------------------------------------------+
* 7F0 |                                                       |
*     =                       LWKIDAL                         =
*     |                                                       |
*     +-------------------------------------------------------+
* FC0
*
*** LWKCCWPG - ISFC Link Work management structure
 
 
  LWKBK Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
LWK_ACTIVE     0009 00000003
LWK_ASYNC      000A 00000002
LWK_BUFFER     0060
LWK_CCWCNT     0036
LWK_CCWFLAG    0034
LWK_CCWNXT     0038
LWK_CCWOPEN    0034 80
LWK_CCWPAGE    0030
LWK_CCWSTOP    003C
LWK_CCW1       0048
LWK_CCW2       0050
LWK_CCW3       0058
LWK_CCW4KFRM   0034 40
LWK_CTLNXT     0020
LWK_CTLPAGE    0018
LWK_CTLSTOP    0028
LWK_EMPTY      0009 00000000
LWK_IDANXT     0040
LWK_IDASTOP    0044
LWK_IMBED      000A 00000003
LWK_MAXCCW     07F0 000000FA
LWK_MAXIDAW    07F0 000000FA
LWK_MAXMBH     07F0 00000040
LWK_OPEN       0009 00000001
LWK_POST       0009 00000005
LWK_PRIORITY   0035
LWK_READ       0008 00000002
LWK_READY      0009 00000002
LWK_SYNC       000A 00000001
LWK_WAIT       0009 00000004
LWK_WRITE      0008 00000001
LWKBKLN        0098 00000198
LWKBKSZ        0098 00000033
LWKBPNT        0004
LWKBYTES       0080
LWKCCW         0010
LWKCCW_TAG     0000
LWKCCW1        0008
LWKEOD         07E0
LWKFPNT        0000
LWKFRMAD       0078
LWKIDAL        07F0
LWKLDVBK       0014
LWKLINST       0088
LWKLNKBK       0010
LWKMBHBK       0098
LWKMBHCT       0094
LWKMODE        000A
LWKREFCT       0090
LWKREQUE       0084
LWKRX_FLAG     000C
LWKRX_STGREQ   000C 80
LWKSEQNO       000E
LWKSTAT        0009
LWKSTGMS       000D
LWKTIC         07E8
LWKTOD         0070
LWKTX_FLAG     000B
LWKTX_RESEND   000B 80
LWKTYPE        0008
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:52:28 EDT.
Copyright IBM Corporation, 1990, 2022