CCWTT | Back to Index page

| Prolog Control Block Contents CCWTT DSECT CCWTTE 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.

CCWTT Prolog | Top of page

     NAME       : HCPCCWTT
     DESCRIPTION: Channel Program Translation Tables
     DSECT      : CCWTT
     FUNCTION   : Address translation table used by the CCW
                  Translation function.
     LOCATED BY : CPTTRTBL (data area in CPTCA)
                  CCW_TRANS_TBL_NEXT
     CREATED BY : HCPCCWTA Macro
     DELETED BY : HCPUNTFR
     SERIALIZED : BEING ACCESSED FOR A UNIQUE TASK
     REFERENCES : None
     COMMENTS   : The first table is contained in the
                  CPTCA.  Additional tables will be built
                  as required.  Note, for most cases we
                  expect to only need one table.
                  The translation table is basically an
                  array of addresses and some flags as
                  follows.
                  If the guest address being used is 64 bit
                  then virt 1 and virt 2 contain the high
                  log order address words.  If the guest
                  address is 31 bits then the address is
                  only contained in virt 2.
                  If the host address is absolute then it
                  is 64 bit and contained in Real 1 and
                  Real 2.  If the host address is logical
                  then it is 31 bit and is contained in
                  Real 2.  CCW_TRANS_TBL_HLOG will tell if
                  the Real address is host logical or host
                  absolute.  If CCW_TRANS_TBL_HLOG is '1'b
                  then the real address is host logical.
                  If CCW_TRANS_TBL_HLOG is '0'b then the
                  real address is host absolute.

CCWTT Control Block Content | Top of page

     CCWTT DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      CCWTT          Channel Program Translation Tables
    0000    0 Bitstring    1 CCW_TRANS_TBL (0)
                                            Translation table entries
    0000    0 Bitstring   24 CCW_TRANS_TBL_ENTRIES (10)
    00F0  240 Signed       4 CCW_TRANS_TBL_NEXT
                                            Next translation table
              0000001F       CCWSIZE        (*-CCWTT+7)/8 DW size of table
          The following DSECT defines each translation table entry

     CCWTTE DSECT
    Top of page

    Hex   Dec Type/Val   Lng Label (dup)    Comments
    ---- ---- --------- ---- -------------- --------
    0000    0 Structure      CCWTTE         Channel Program Translation Tables
    0000    0 Dbl-Word     8 CCW_TRANS_TBL_64ADR (0)
                                            64 bit virtual address
    0000    0 Signed       4 CCW_TRANS_TBL_VHI
                                            Hi order word 64 bit addr
    0004    4 Signed       4 CCW_TRANS_TBL_VADDR
                                            Virtual page address or lo order
                                            word 64 bit addr
          CCW_TRANS_TBL_R64AD holds a 64 bit Host Absolute address or
          a 31 bit Host Logical address.   If a host absolute address
          then CCW_TRANS_TBL_HLOG = 0,  if a host logical address
          then CCW_TRANS_TBL_HLOG = 1.
    0008    8 Dbl-Word     8 CCW_TRANS_TBL_R64AD (0)
                                            64 bit Host Absolute
    0008    8 Signed       4 CCW_TRANS_TBL_RHI
                                            Hi word Host Abs addr
    000C   12 Signed       4 CCW_TRANS_TBL_RADDR
                                            Low word host absolute address or
                                            a 31 bit host logical addre The
                                            contents of this field based on
                                            CCW_TRANS_TBL_HLOG
    0010   16 Bitstring    1 CCW_TRANS_TBL_FLAGS
                                            Address translation flags
              1... ....      CCW_TRANS_TBL_USED
                                            X'80' CCW_TRANS_TBL_USED Entry in
                                            use
              .1.. ....      CCW_TRANS_TBL_CKF
                                            X'40' CCW_TRANS_TBL_CKF Checked
                                            FETCH protect
              ..1. ....      CCW_TRANS_TBL_CKS
                                            X'20' CCW_TRANS_TBL_CKS Checked
                                            STORE protect
              ...1 ....      CCW_TRANS_TBL_FETCH
                                            X'10' CCW_TRANS_TBL_FETCH FETCH
                                            allowed
              .... 1...      CCW_TRANS_TBL_STORE
                                            X'08' CCW_TRANS_TBL_STORE STORE
                                            allowed
              .... .1..      CCW_TRANS_TBL_HLOG
                                            X'04' CCW_TRANS_TBL_HLOG ON =
                                            Host Logical ad OFF = Host
                                            Absolute addr
    0011   17 Bitstring    7 *              Reserved for future use
              00000018       CCWEL          *-CCWTTE
              0000000A       CCW_TRANS_TBL_ENTRY_NBR
                                            10 Number of table entries
              0000000A       CCWNE          CCW_TRANS_TBL_ENTRY_NBR

CCWTT Storage Layout | Top of page

    *** CCWTT - Channel Program Translation Tables
    *
    *     +-------------------------------------------------------+
    *   0 |                                                       |
    *     =                CCW_TRANS_TBL_ENTRIES                  =
    *     |                                                       |
    *     +---------------------------+---------------------------+
    *  F0 |    CCW_TRANS_TBL_NEXT     | F4
    *     +---------------------------+
    *
    *** CCWTT - Channel Program Translation Tables

    *** CCWTTE - Channel Program Translation Tables
    *
    *     +---------------------------+---------------------------+
    *   0 |    CCW_TRANS_TBL_VHI      |   CCW_TRANS_TBL_VADDR     |
    *     +---------------------------+---------------------------+
    *   8 |    CCW_TRANS_TBL_RHI      |   CCW_TRANS_TBL_RADDR     |
    *     +------+--------------------+---------------------------+
    *  10 |(010) |////////////////////////////////////////////////|
    *     +------+------------------------------------------------+
    *  18
    *
    *** CCWTTE - Channel Program Translation Tables

CCWTT Cross Reference | Top of page

    Symbol         Dspl Value
    -------------- ---- -----
    CCW_TRANS_TBL  0000
    CCW_TRANS_TBL_CKF
                   0010 40
    CCW_TRANS_TBL_CKS
                   0010 20
    CCW_TRANS_TBL_ENTRIES
                   0000
    CCW_TRANS_TBL_ENTRY_NBR
                   0011 0000000A
    CCW_TRANS_TBL_FLAGS
                   0010
    CCW_TRANS_TBL_FETCH
                   0010 10
    CCW_TRANS_TBL_HLOG
                   0010 04
    CCW_TRANS_TBL_NEXT
                   00F0
    CCW_TRANS_TBL_R64AD
                   0008
    CCW_TRANS_TBL_RHI
                   0008
    CCW_TRANS_TBL_RADDR
                   000C
    CCW_TRANS_TBL_STORE
                   0010 08
    CCW_TRANS_TBL_USED
                   0010 80
    CCW_TRANS_TBL_VHI
                   0000
    CCW_TRANS_TBL_VADDR
                   0004
    CCW_TRANS_TBL_64ADR
                   0000
    CCWEL          0011 00000018
    CCWNE          0011 0000000A
    CCWSIZE        00F0 0000001F

This information is based on z/VM 7.2.0 Last updated on 24 Jun 2020 at 09:27:15 EDT.
Copyright IBM Corporation, 1990, 2020