ASCE Back to Index page
 
Prolog 
Control Block Contents 
   ASCE 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.


  ASCE Prolog Top of page
 
 NAME       : HCPASCE
 DESCRIPTION: Address-Space-Control Element
 DSECT      : ASCE
 FUNCTION   : This DSECT maps a z/Arch address-space-control
              element.  The format of an address-space-control
              element is architected, and described in the
              Principles of Operation.
 LOCATED BY : CR1      is the ASCE for the primary address space.
              CR7      is the ASCE for the secondary address space.
              CR13     is the ASCE for the home address space.
              ASTASCE  in an ASTE.
              VMDPASCE is the ASCE for a virtual CPU's current
              primary address space.
              PFXSXASC is the ASCE for the system-execution space.
 CREATED BY : HCPASMCR when an address space is created.
              HCPSSMCR when the system-execution address space is
              created.
              HCPFMUSG when the full track cache address space
              is created.
              HCPHDTMA when an address space is expanded.
              HCPHDTNL when an address space is compressed.
 DELETED BY : HCPASMDS when the address space is destroyed.
 RELOCATION CONSIDERATIONS : None
 
 
  ASCE Control Block Content Top of page
 

 ASCE DSECT Top of page
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure ASCE Address-Space-Control Element ASCE - 8 bytes, 64 bits 0000 0 Dbl-Word 8 ASCEALL (0) Entire ASCE 64-bit mask X'FFFFFFFFFFFFF000' Isolate STO, RTO or RSTO 00000AF0 ASCEMSK PFXGPFRA 64-bit mask in PFXPG 00FFFFFF ASCETOMH X'FFFFFFFF' High word of mask value 00000AF4 ASCEMSKL PFXGPFRA+4,4 Low word of mask in PFXPG 00FFF000 ASCETOML X'FFFFF000' Low word of mask value The next four masks are also used by the STD, RTD and RSD. 64-bit mask X'0000000000000200' 32-bit high X'00000000' 00000200 ASCEGSM X'00000200' Isolate subspace-group control bit 64-bit mask X'0000000000000100' 32-bit high X'00000000' 00000100 ASCEPSM X'00000100' Isolate private-space control bit 64-bit mask X'0000000000000080' 32-bit high X'00000000' 1... .... ASCESSM X'00000080' Isolate storage-alteration- event control bit 64-bit mask X'0000000000000040' 32-bit high X'00000000' .1.. .... ASCEXSM X'00000040' Isolate space-switch-event control bit 64-bit mask X'0000000000000020' 32-bit high X'00000000' ..1. .... ASCERBM X'00000020' Isolate real-space control bit - R=0: ASCE is an RTD or STD - R=1: ASCE is an RSD 64-bit mask X'000000000000000C' 32-bit high X'00000000' .... 11.. ASCEDTMK X'0000000C' Isolate designation type bits 00000002 ASCEDTSHF 2 Bits DT is offset from right edge of ASCE 64-bit mask X'0000000000000003' 32-bit high X'00000000' .... ..11 ASCETLMK X'00000003' Isolate table length bits 0000000C ASCETLBYT 12 Bits to shift (TL+1) to get number of bytes in table 0000 0 Signed 4 ASCEW0 (0) ASCE Word 0 0000 0 Bitstring 1 ASCEW0B0 (0) ASCE Word 0 Byte 0 0000 0 Bitstring 1 ASCEBYT0 ASCE Byte 0 0001 1 Bitstring 1 ASCEW0B1 (0) ASCE Word 0 Byte 1 0001 1 Bitstring 1 ASCEBYT1 ASCE Byte 1 0002 2 Bitstring 1 ASCEW0B2 (0) ASCE Word 0 Byte 2 0002 2 Bitstring 1 ASCEBYT2 ASCE Byte 2 0003 3 Bitstring 1 ASCEW0B3 (0) ASCE Word 0 Byte 3 0003 3 Bitstring 1 ASCEBYT3 ASCE Byte 3 0004 4 Signed 4 ASCEW1 (0) ASCE Word 1 0004 4 Bitstring 1 ASCEW1B0 (0) ASCE Word 1 Byte 0 0004 4 Bitstring 1 ASCEBYT4 ASCE Byte 4 0005 5 Bitstring 1 ASCEW1B1 (0) ASCE Word 1 Byte 1 0005 5 Bitstring 1 ASCEBYT5 ASCE Byte 5 0006 6 Bitstring 1 ASCEW1B2 (0) ASCE Word 1 Byte 2 0006 6 Bitstring 1 ASCEBYT6 ASCE Byte 6 .... ..1. ASCEGBIT X'02' Subspace-group control bit .... ...1 ASCEPBIT X'01' Private-space control bit 0007 7 Bitstring 1 ASCEW1B3 (0) ASCE Word 1 Byte 3 0007 7 Bitstring 1 ASCEBYT7 ASCE Byte 7 1... .... ASCESBIT X'80' Storage-alteration-event control bit .1.. .... ASCEXBIT X'40' Space-switch-event control bit ..1. .... ASCERBIT X'20' Real-space control bit - R=0: ASCE is an RTD or STD - R=1: ASCE is an RSD .... 11.. ASCETBIT X'0C' Designation type bits The following four designation type bits are valid only if the real-space control bit (ASCERBIT) = zero (R=0) .... 11.. ASCERFTD X'0C' ASCE is an RFT designation .... 1... ASCERSTD X'08' ASCE is an RST designation .... .1.. ASCERTTD X'04' ASCE is an RTT designation .... .... ASCESTD X'00' ASCE is an ST designation .... ..11 ASCELBIT X'03' Table length bits
 
 
  ASCE Storage Layout Top of page
 
          
*** ASCE - Address-Space-Control Element
*
*
*** ASCE - Address-Space-Control Element
          
*** Overlay for ASCE in ASCE
*
*     +------+------+------+------+------+------+------+------+
*   0 |:EBYT0|:EBYT1|:EBYT2|:EBYT3|:EBYT4|:EBYT5|:EBYT6|:EBYT7|
*     +------+------+------+------+------+------+------+------+
*   8
*
*** Overlay for ASCE in ASCE
 
 
  ASCE Cross Reference Top of page
 
 
Symbol         Dspl Value
-------------- ---- -----
ASCEALL        0000
ASCEBYT0       0000
ASCEBYT1       0001
ASCEBYT2       0002
ASCEBYT3       0003
ASCEBYT4       0004
ASCEBYT5       0005
ASCEBYT6       0006
ASCEBYT7       0007
ASCEDTMK       0000 0C
ASCEDTSHF      0000 00000002
ASCEGBIT       0006 02
ASCEGSM        0000 00000200
ASCELBIT       0007 03
ASCEMSK        0000 00000AF0
ASCEMSKL       0000 00000AF4
ASCEPBIT       0006 01
ASCEPSM        0000 00000100
ASCERBIT       0007 20
ASCERBM        0000 20
ASCERFTD       0007 0C
ASCERSTD       0007 08
ASCERTTD       0007 04
ASCESBIT       0007 80
ASCESSM        0000 80
ASCESTD        0007 00
ASCETBIT       0007 0C
ASCETLBYT      0000 0000000C
ASCETLMK       0000 03
ASCETOMH       0000 00FFFFFF
ASCETOML       0000 00FFF000
ASCEW0         0000
ASCEW0B0       0000
ASCEW0B1       0001
ASCEW0B2       0002
ASCEW0B3       0003
ASCEW1         0004
ASCEW1B0       0004
ASCEW1B1       0005
ASCEW1B2       0006
ASCEW1B3       0007
ASCEXBIT       0007 40
ASCEXSM        0000 40
 
This information is based on z/VM 7.3.0 Last updated on 22 Jun 2022 at 15:58:16 EDT.
Copyright IBM Corporation, 1990, 2022