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Prolog Control Block Contents ASTE DSECT Storage Layout Cross Reference (Contains links to field and bit definitions) |
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NAME : HCPASTE
DESCRIPTION: ASN-Second-Table Entry
DSECT : ASTE
FUNCTION : The ASTE maps the storage associated with one entry
of an ASN-Second Table. The entry is used in ASN
and AR translation, and is also used to access
other information associated with an address space.
Notes : In ESA/390, CR0.15 is the address space control
bit. If set the ASTE length is 64 bytes.
Otherwise, the length is 16 bytes. The
first 16 bytes are mapped identically
regardless of the length.
Notes : In z/Arch, all ASTEs are 64 bytes in length,
CR0.15 does not apply. However, the z/Arch ASTE
is slightly different from the ESA/390 ASTE.
We need both the
z/Arch ASTE mapping (for host ASTEs and z/Arch
guest ASTEs) and the ESA/390 ASTE mapping (for
ESA/390 guest ASTEs). Since most of the ASTE
definition is identical for both ASTE formats,
the entire definition is not duplicated.
Instead, only the 3 words ( words 2, 3 and 6 )
which differ between the two formats are
defined separately.
LOCATED BY : ASN and AR translation
ASTEs for address spaces built by CP are located by
the ASCASTE pointer of the associated ASCBK.
An ASTE is part of an ASN second table (AST). The
beginning of the table is pointed to by:
- An ASN first table entry (AFTE)
The AST is indexed into by an ASN second index (ASX).
An ASTE may be directly pointed to by:
- An access list entry (ALE)
- CR5 (when the ASTE is the primary ASTE)
- An entry table entry (ETE)
There is also an ASTE within MWBK.
CREATED BY : ASTEs for address spaces built by CP are
initialized by HCPASMCR, though the storage
is managed by HCPVCB.
Within MWBK: HCPMWPBL - MAS work area build
The ASTE is also used to map guest ASN Second Table
Entries in guest storage.
DELETED BY : Once storage has been allocated as an ASTE for an
address space built by CP, it can never be used for
anything else. Though it may no longer represent an
ASTE for an active address space (HCPASMDS "destroys"
a space), the ASTE itself will be held in reserve
until it can be given out again as an ASTE (with a
different ASTE sequence number). The popular phrase
is "ASTEs are forever".
Within MWBK: HCPMWPDL - MAS work area delete
SERIALIZED : ASTEs for address spaces built by CP are generally
serialized by the ASCBK lock in the associated ASCBK.
Addtionally, for V=V guests, ASTASCE is
serialized by the owning virtual configuration's
VMDPTIL (in the base VMDBK) held exclusive (to
change).
The ASTALD field is serialized by the ALCBK lock in
ALCBK associated with the access list, if there is a
primary-space access list.
Within MWBK: See MWBK prologue.
When used to map guest storage, the user of the
DSECT is responsible for serialization.
RELOCATION CONSIDERATIONS : None
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| ASTE Control Block Content | Top of page |
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| ASTE Storage Layout | Top of page |
*** ASTE - ASN-Second-Table Entry
*
* +---------------------------+-------------+------+------+
* 0 | ASTATO | ASTAX |:ATL_0|:ATL_1|
* +---------------------------+-------------+------+------+
* 8 | ASTSTD | ASTLTD |
* +---------------------------+---------------------------+
* 10
*
*** ASTE - ASN-Second-Table Entry
*** Overlay for ASTSTD in ASTE
*
* +------+--------------------+
* 8 |:STDB0|////////////////////| C
* +------+--------------------+
*
*** Overlay for ASTSTD in ASTE
*** Overlay for ASTLTD in ASTE
*
* +------+--------------------+
* 8 ... C |:LTDB0|////////////////////|
* +------+--------------------+
* 10
*
*** Overlay for ASTLTD in ASTE
*** Overlay for ASTSTD in ASTE
*
* +-------------------------------------------------------+
* 8 | ASTASCE |
* +-------------------------------------------------------+
* 10
*
*** Overlay for ASTSTD in ASTE
*** Overlay for ASTASCE in ASTE
*
* +---------------------------+---------------------------+
* 8 | ASTASCE0 | ASTASCE1 |
* +---------------------------+---------------------------+
* 10 | ASTALD | ASTSN |
* +---------------------------+---------------------------+
* 18 | ASTGLTD | 1C
* +---------------------------+
*
*** Overlay for ASTASCE in ASTE
*** Overlay for ASTGLTD in ASTE
*
* +---------------------------+------+--------------------+
* 18 | ASTGLFTD |:STAT |////////////////////|
* +---------------------------+------+--------------------+
* 20 | ASTASTEO | ASTSCRSN |
* +---------------------------+---------------------------+
* 28 |///////////////////////////| ASTIN |
* +---------------------------+---------------------------+
* 30 |///////////////////////////////////////////////////////|
* |///////////////////////////////////////////////////////|
* +-------------------------------------------------------+
* 40
*
*** Overlay for ASTGLTD in ASTE
*** Overlay for ASTATO in ASTE
*
* +------+-------------+------+
* 0 |:ATOB0|/////////////|:ATOB3| 4
* +------+-------------+------+
*
*** Overlay for ASTATO in ASTE
*** Overlay for ASTATL in ASTE
*
* +------+------+
* 0 ... 6 |//////|:ATLB1|
* +------+------+
* 8
*
*** Overlay for ASTATL in ASTE
*** Overlay for ASTPRGM in ASTE
*
* +---------------------------+
* 18 ... 1C | ASTASCBK |
* +---------------------------+
* 20
*
*** Overlay for ASTPRGM in ASTE
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| ASTE Cross Reference | Top of page |
Symbol Dspl Value -------------- ---- ----- ASTALD 0010 ASTASCBK 001C ASTASCE 0008 ASTASCE0 0008 ASTASCE1 000C ASTASTEO 0020 ASTATL 0006 ASTATL_0 0006 ASTATL_1 0007 ASTATLB1 0007 ASTATLM 0004 000ASTW1 ASTATLZ 0007 0F ASTATO 0000 ASTATOB0 0000 ASTATOB3 0003 ASTATOM 0000 000ASTW0 ASTAT370 0003 03 ASTAX 0004 ASTBASI 0000 ASTBSALG 0000 00000010 ASTBSIZE 0030 00000002 ASTCA 0007 02 ASTEASIT 0020 ASTEID 0020 ASTEID1 0020 ASTEID2 0024 ASTEXALG 0000 00000040 ASTGLFTD 0018 ASTGLTD 0018 ASTIN 002C ASTINACT 001C 80 ASTINV 0000 80 ASTLEN 0030 00000040 ASTLTD 000C ASTLTDB0 000C ASTLTDSL 000C 80 ASTPRGM 001C ASTRA 0007 01 ASTSCRSN 0024 ASTSIZE 0030 00000008 ASTSN 0014 ASTSNJM 0014 00 ASTSNMAX 0014 000ASTSN ASTSTAT 001C ASTSTD 0008 ASTSTDB0 0008 ASTSTDSS 0008 80 ASTW0 0000 ASTW1 0004 |
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