FCTBK | Back to Index page

| Prolog Control Block Contents FCTBK 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.

FCTBK Prolog | Top of page

     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
     RELOCATION CONSIDERATIONS : None
     NOTES      : FCTBKs are obtained by HCPFGST
                  FCTBKs are released by HCPFRST

FCTBK Control Block Content | Top of page

     FCTBK DSECT
    Top of page

    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    1 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 Bitstring    1 FCT_2 (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' FCTNCE 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' FCTMDRSZ 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' FCTFMT1 Using format 1 CCWs
              1... ....      FCTPCI         X'80' FCTPCI Redefined for FTS:
                                            PCI encountered in CP
              .1.. ....      FCTOVRFL       X'40' FCTOVRFL We have overflowed
              ..1. ....      FCTNOSEK       X'20' FCTNOSEK No seeks allowed
              ...1 ....      FCTSEEKD       X'10' FCTSEEKD Seek or locate
                                            done
              .... 1...      FCTWRITE       X'08' FCTWRITE CP has a write CCW
              .... .1..      FCTREAD        X'04' FCTREAD CP has a "read" CCW
              .... .1..      FCTBADLN       X'04' FCTBADLN Redefined for FTS:
                                            Bad length on last CCW
              .... ..1.      FCTMULTI       X'02' FCTMULTI Multitrack CCW
              .... ...1      FCTMSEEK       X'01' FCTMSEEK Multiple seeks
    0179  377 Bitstring    1 FCTSTYPE       Guest storage mode and
                                            miscellaneous bits
              .1.. ....      FCTPASS2       X'40' FCTPASS2 HCPFTR is in PASS
                                            2
              ..1. ....      FCTSPLIT       X'20' FCTSPLIT Used by FUN when
                                            it gets split status to avoid
                                            puging MDC if ok
              ...1 ....      FCTF2IDA       X'10' FCTF2IDA Guest using Fmt-2
                                            IDAWs
              .... 1...      FCT2KIDA       X'08' FCT2KIDA 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.
              .... ...1      FCTMIDA        X'01' FCTMIDA Current CCW using
                                            MIDAWs
    017A  378 Bitstring    2 *              IBM RESERVED
    017C  380 Signed       4 FCTVCCCH       Virtual ccccCCCh address
    0180  384 Signed       4 FCTNEXT        Address of next FCTBK
    0184  388 Bitstring    1 FCTFLAG2       Second flag byte
              1... ....      FCTFBA         X'80' FCTFBA This is an FBA
                                            program
              .1.. ....      FCTDX          X'40' FCTDX DX or SFM has been
                                            done
              ..1. ....      FCTR0          X'20' FCTR0 Oriented to Record
                                            zero
              ...1 ....      FCTDED         X'10' FCTDED Dedicated device
              .... 1...      FCTDIDIO       X'08' FCTDIDIO I/O was done
                                            during MDC simulation
              .... .1..      FCTDCHN        X'04' FCTDCHN This CCW is data
                                            chained
              .... ..1.      FCTCKDCN       X'02' FCTCKDCN CKD conversion
                                            mode
              .... ...1      FCTREGDF       X'01' FCTREGDF Regular data
                                            format mode
    0185  389 Bitstring    1 FCTFLAG3       Third flag byte
              1... ....      FCTPREFX       X'80' FCTPREFX Prefix CCW is
                                            present
              .1.. ....      FCTCANTS       X'40' FCTCANTS A CCW that can be
                                            timestamped is present in the
                                            channel program
    0186  390 Bitstring    2 *              IBM RESERVED
    0188  392 Signed       4 FCTHOST_CYL32  Host cylinder 0CCCcccc
              ST_CYL32       FCTCLEAR       00034 FCT_2,*-FCT_2 Area to clear
    018C  396 Signed       4 FCTCCCH1       CCCH work area
    0190  400 Signed       4 FCTCCCH2       CCCH work area
    0194  404 Signed       4 FCTFLEYE (0)   Word to include reserved byte
                                            plus eyecatcher
    0194  404 Bitstring    1 *              IBM RESERVED
    0195  405 Character    3 FCTEYE         Eye catcher 'FCT'
              00000198       FCTEND         *
              00000198       FCTBSIZE       *-FCTBK Size in bytes
              00000033       FCTBKDWS       (((*-FCTBK)+7)/8) Size in
                                            doublewords
              00000031       FCTBKFSZ       FCTBKDWS-2 Size minus trailer

FCTBK Storage Layout | Top of page

    *** 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|/////////////|         FCTVCCCH          |
    *     +------+------+-------------+------+------+-------------+
    * 180 |         FCTNEXT           |:FLAG2|:FLAG3|/////////////|
    *     +---------------------------+------+------+-------------+
    * 188 |      FCTHOST_CYL32        |         FCTCCCH1          |
    *     +---------------------------+------+--------------------+
    * 190 |         FCTCCCH2          |//////|      FCTEYE        |
    *     +---------------------------+------+--------------------+
    * 198
    *
    *** Overlay for FCTEOHCP in FCTBK

FCTBK Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    FCT_2          0158
    FCTBADLN       0178 04
    FCTBKDWS       0195 00000033
    FCTBKFSZ       0195 00000031
    FCTBKSZ        016C
    FCTBLKAP       0144
    FCTBSIZE       0195 00000198
    FCTCANTS       0185 40
    FCTCCCH1       018C
    FCTCCCH2       0190
    FCTCKDCN       0184 02
    FCTCLEAR       0188 ST_CYL32
    FCTDCHN        0184 04
    FCTDED         0184 10
    FCTDIDIO       0184 08
    FCTDL          0174
    FCTDX          0184 40
    FCTEHLCP       0150
    FCTEND         0195 00000198
    FCTEOGCP       014C
    FCTEOHCP       016C
    FCTEOTR        0140
    FCTEYE         0195
    FCTFBA         0184 80
    FCTFLAG        0178
    FCTFLAG2       0184
    FCTFLAG3       0185
    FCTFLB64       0158
    FCTFLEYE       0194
    FCTFMT1        0178 80
    FCTFREES       0000 00000120
    FCTF2IDA       0179 10
    FCTGCPA        0154
    FCTHH          016E
    FCTHOST_CYL32  0188
    FCTLAST        0160
    FCTLOCF        0144
    FCTLOCL        0148
    FCTMDCFL       0170
    FCTMDRSZ       0174 000FCTDL
    FCTMIDA        0179 01
    FCTMSEEK       0178 01
    FCTMULTI       0178 02
    FCTNCE         0170 80
    FCTNEXT        0180
    FCTNOSEK       0178 20
    FCTOVRFL       0178 40
    FCTPASS2       0179 40
    FCTPCI         0178 80
    FCTPREFX       0185 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
    FCTVCCCH       017C
    FCTWORKA       0000
    FCTWRITE       0178 08
    FCT2KIDA       0179 08

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:28:12 EDT.
Copyright IBM Corporation, 1990, 2020