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

FCTBK

Prolog  

Control Block Contents  
   FCTBK DSECT

Storage Layout  

Cross Reference (Contains links to field and bit definitions)  


FCTBK Prolog

 Name       : HCPFCTBK
 Description: Fast CCW Translation BlocK
 DSECT      : FCTBK
 Function   : This block contains room to hold translated
              guest CCWs and control information.
 Located by : IORCPA.
 Created by : HCPFTRAN.
 Deleted by : HCPFTRAN, HCPFUNTR, HCPFUNFR
 Notes      : FCTBKs are obtained by HCPFGST
              FCTBKs are released by HCPFRST

 

FCTBK Control Block Content


FCTBK DSECT

Hex   Dec Type/Val   Lng Label (dup)    Comments
---- ---- --------- ---- -------------- --------
0000    0 Structure      FCTBK          Fast CCW Translation BlocK
0000    0 Dbl-Word     8 FCTWORKA (40)  Room for CCWS and Parms
          00000120       FCTFREES       ((*-FCTBK)-16-16) Save room for 2
                                        CCWs and TIC block when
                                        allocating free storage.
       Fixed trailer fields for (E)CKD and FBA.
0140  320 Bitstring   72 FCTTRLR (0)    Fixed information
       FBA Only trailer fields -
0140  320 Signed       4 FCTSEXT        Starting Record
0144  324 Signed       4 FCTLOCF        First host block # from most
                                        recent LOCATE
0148  328 Signed       4 FCTLOCL        Last host block # from most
                                        recent LOCATE
       (E)CKD Only trailer fields -
0140  320 Signed       4 FCTEOTR        End of track
0144  324 Signed       4 *              Reserved
0148  328 Signed       4 *              Reserved
       Common (E)CKD and FBA trailer fields -
014C  332 Signed       4 FCTEOGCP       End of guest channel program
0150  336 Signed       4 FCTEHLCP       Host Logical end of the channel
                                        program
0154  340 Address      4 FCTGCPA        Start of guest CCWs
0158  344 Character   44 FCTCLEAR (0)   Area that must be cleared
0158  344 Signed       4 FCTFLB64       Queue of 64 bit TLBs
015C  348 Signed       4 FCTTCHBK       Address of TCHBK
0160  352 Signed       4 FCTLAST        Last FCTBK queued or addr of this
                                        FCTBK if no additional FCTBKs
                                        queued
0164  356 Address      4 FCTTICAN       TIC anchor
0168  360 Signed       4 FCTUTRAN       Untrans Entry anchor
      The next 3 words are ORGed by MDC fields.  Only use these
      fields after calls to MDC.
016C  364 Signed       4 FCTEOHCP       Host Absolute end of channel
                                        program
0170  368 Signed       4 *              Only use this on pass 2
0174  372 Signed       4 *              Only use this on pass 2
       Redefinition of LOCF as used by HCPFTR
0144  324 Signed       4 FCTBLKAP       Blocks per "cylinder"
       Redefinition of TLB area for Full Track Caching
016C  364 Signed       2 FCTBKSZ (0)    ECKD block size
016C  364 Signed       2 FCTRDSZ        Size of read
016E  366 Signed       2 FCTHH          Head of seek arg
0170  368 Signed       2 FCTTCKEY (0)   MDC device ID
      FCTNCE is used to turn on the high order byte of FCTTCKEY.
      When FCTTCKEY is negative or zero, caching is bypassed.
0170  368 Bitstring    1 FCTMDCFL       1st byte of FCTTCKEY
          1... ....      FCTNCE         X'80' Not eligible for MDC
0171  369 Bitstring    1 *              2nd byte of FCTTCKEY
0172  370 Signed       2 FCTTPCYL       Tracks per cylinder
0174  372 Signed       2 FCTDL          Current record's length
          000FCTDL       FCTMDRSZ       X'DFEE' Max dasd record size that
                                        MDC will accept. This is the max
                                        value for 3390's - 57326 bytes of
                                        usable track capacity
0176  374 Signed       2 FCTRESID       Residual count
0178  376 Bitstring    1 FCTFLAG
          1... ....      FCTFMT1        X'80' Using format 1 CCWs
          1... ....      FCTPCI         X'80' Redefined for FTS: PCI
                                        encountered in CP
          .1.. ....      FCTOVRFL       X'40' We have overflowed
          ..1. ....      FCTNOSEK       X'20' No seeks allowed
          ...1 ....      FCTSEEKD       X'10' Seek or locate done
          .... 1...      FCTWRITE       X'08' CP has a write CCW
          .... .1..      FCTREAD        X'04' CP has a "read" CCW
          .... .1..      FCTBADLN       X'04' Redefined for FTS: Bad
                                        length on last CCW
          .... ..1.      FCTMULTI       X'02' Multitrack CCW
          .... ...1      FCTMSEEK       X'01' Multiple seeks
0179  377 Bitstring    1 FCTSTYPE       Guest storage mode and
                                        miscellaneous bits
          .1.. ....      FCTPASS2       X'40' HCPFTR is in PASS 2
          ..1. ....      FCTSPLIT       X'20' Used by FUN when it gets
                                        split status to avoid puging MDC
                                        if ok
          ...1 ....      FCTF2IDA       X'10' Guest using Fmt-2 IDAWs
          .... 1...      FCT2KIDA       X'08' Guest/Host IDAWs will be 2K
                                        boundary. The guest could be
                                        using format-1 or format-2/2K. In
                                        both cases CP will trans to
                                        format-2/2K. If the bit is off it
                                        means the guest is using fmt-2/4K
                                        IDAWs and so will CP.
017A  378 Bitstring    2 FCTHCC         Host cylinder address
017C  380 Signed       4 FCTVCCHH       Virtual track address
0180  384 Signed       4 FCTNEXT        Address of next FCTBK
0184  388 Signed       4 FCTFLEYE (0)   Word to define flag plus the
                                        eyecatcher
0184  388 Bitstring    1 FCTFLAG2       Second flag byte
          1... ....      FCTFBA         X'80' This is an FBA program
          .1.. ....      FCTDX          X'40' DX or SFM has been done
          ..1. ....      FCTR0          X'20' Oriented to Record zero
          ...1 ....      FCTDED         X'10' Dedicated device
          .... 1...      FCTDIDIO       X'08' I/O was done during MDC
                                        simulation
          .... .1..      FCTDCHN        X'04' This CCW is data chained
          .... ..1.      FCTCKDCN       X'02' CKD conversion mode
          .... ...1      FCTREGDF       X'01' Regular data format mode
0185  389 Character    3 FCTEYE         Eye catcher 'FCT'
          00000188       FCTEND         *
          00000188       FCTBSIZE       *-FCTBK Size in bytes
          00000031       FCTBKDWS       (((*-FCTBK)+7)/8) Size in
                                        doublewords
          0000002F       FCTBKFSZ       FCTBKDWS-2 Size minus trailer

 

FCTBK Storage Layout

          
*** FCTBK - Fast CCW Translation BlocK
*
*     +-------------------------------------------------------+
*   0 |                                                       |
*     =                       FCTWORKA                        =
*     |                                                       |
*     +---------------------------+---------------------------+
* 140 |         FCTSEXT           |         FCTLOCF           |
*     +---------------------------+---------------------------+
* 148 |         FCTLOCL           | 14C
*     +---------------------------+
*
*** FCTBK - Fast CCW Translation BlocK
          
*** Overlay for FCTTRLR in FCTBK
*
*     +---------------------------+---------------------------+
* 140 |         FCTEOTR           |///////////////////////////|
*     +---------------------------+---------------------------+
* 148 |///////////////////////////|         FCTEOGCP          |
*     +---------------------------+---------------------------+
* 150 |         FCTEHLCP          |         FCTGCPA           |
*     +---------------------------+---------------------------+
* 158 |         FCTFLB64          |         FCTTCHBK          |
*     +---------------------------+---------------------------+
* 160 |         FCTLAST           |         FCTTICAN          |
*     +---------------------------+---------------------------+
* 168 |         FCTUTRAN          |         FCTEOHCP          |
*     +---------------------------+---------------------------+
* 170 |///////////////////////////|///////////////////////////|
*     +---------------------------+---------------------------+
* 178
*
*** Overlay for FCTTRLR in FCTBK
          
*** Overlay for FCTLOCF in FCTBK
*
*                                 +---------------------------+
* 140 ...                     144 |         FCTBLKAP          |
*                                 +---------------------------+
* 148
*
*** Overlay for FCTLOCF in FCTBK
          
*** Overlay for FCTEOHCP in FCTBK
*
*                                 +-------------+-------------+
* 168 ...                     16C |  FCTRDSZ    |   FCTHH     |
*     +------+------+-------------+-------------+-------------+
* 170 |:MDCFL|//////|  FCTTPCYL   |   FCTDL     |  FCTRESID   |
*     +------+------+-------------+-------------+-------------+
* 178 |:FLAG |:STYPE|   FCTHCC    |         FCTVCCHH          |
*     +------+------+-------------+------+--------------------+
* 180 |         FCTNEXT           |:FLAG2|      FCTEYE        |
*     +---------------------------+------+--------------------+
* 188
*
*** Overlay for FCTEOHCP in FCTBK

 

FCTBK Cross Reference

Symbol         Dspl Value
-------------- ---- -----
FCTBADLN       0178 04
FCTBKDWS       0185 00000031
FCTBKFSZ       0185 0000002F
FCTBKSZ        016C
FCTBLKAP       0144
FCTBSIZE       0185 00000188
FCTCKDCN       0184 02
FCTCLEAR       0158
FCTDCHN        0184 04
FCTDED         0184 10
FCTDIDIO       0184 08
FCTDL          0174
FCTDX          0184 40
FCTEHLCP       0150
FCTEND         0185 00000188
FCTEOGCP       014C
FCTEOHCP       016C
FCTEOTR        0140
FCTEYE         0185
FCTFBA         0184 80
FCTFLAG        0178
FCTFLAG2       0184
FCTFLB64       0158
FCTFLEYE       0184
FCTFMT1        0178 80
FCTFREES       0000 00000120
FCTF2IDA       0179 10
FCTGCPA        0154
FCTHCC         017A
FCTHH          016E
FCTLAST        0160
FCTLOCF        0144
FCTLOCL        0148
FCTMDCFL       0170
FCTMDRSZ       0174 000FCTDL
FCTMSEEK       0178 01
FCTMULTI       0178 02
FCTNCE         0170 80
FCTNEXT        0180
FCTNOSEK       0178 20
FCTOVRFL       0178 40
FCTPASS2       0179 40
FCTPCI         0178 80
FCTRDSZ        016C
FCTREAD        0178 04
FCTREGDF       0184 01
FCTRESID       0176
FCTR0          0184 20
FCTSEEKD       0178 10
FCTSEXT        0140
FCTSPLIT       0179 20
FCTSTYPE       0179
FCTTCHBK       015C
FCTTCKEY       0170
FCTTICAN       0164
FCTTPCYL       0172
FCTTRLR        0140
FCTUTRAN       0168
FCTVCCHH       017C
FCTWORKA       0000
FCTWRITE       0178 08
FCT2KIDA       0179 08

This information is based on z/VM V5R2.0. Last updated on 12 Apr 2006 at 16:55:20 EDT.
Copyright IBM Corporation, 1990, 2005