Programming Interface Information:
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used as Programming Interfaces of z/VM. |
HALBK
PrologControl Block Contents
HALBK DSECT
Storage Layout
Cross Reference
HALBK Prolog
NAME : HCPHALBK DESCRIPTION: Host-ART lookaside block DSECT : HALBK FUNCTION : The HALBK maps ALETs to I-ASITs for host-access-register translation. SERIALIZED : Each task is responsible for its own serialization COMMENTS : This block is meant to be used with the HCPHALM macro. The user must: - acquire HALBK storage - have an active HCPUSING on the block - fill in the header. Then HCPHALM may be used to search and manipulate entries in this block. The count of the number of entries in the HALBK must fit in a fullword; that's the only restriction on HALBK size. If, however, the total size of the HALBK (header + (entry length * number of entries)) could be greater than 509 doublewords, the PAGES=DECIDE option should be used on the HCPGETST and HCPRELST macros.
HALBK Control Block Content
HALBK DSECT
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure HALBK Host-ART lookaside block 0000 0 Character 16 HALHDR HALBK header 0010 16 Character 16 HALENTRY HALBK entry (there can be more than one of these). Mapping of the HALBK header 0000 0 Signed 4 HALMXENT Maximum number of HALBK .entries 0004 4 Address 4 HALVMDBK Address of the base VMDBK .associated with the access .list to which the ALETs .belong. 0008 8 Character 8 * Reserved for IBM use. Mapping of HALBK entries 0010 16 Bitstring 1 HALSTATE State flag for the entry 00000000 HALINVAL X'00' The entry is invalid (does .not contain an ALET/i-ASIT .pair). 00000001 HALVALID X'01' The entry is valid (does .contain an ALET/i-ASIT .pair). 00000000 * 0011 17 Bitstring 3 * Reserved for IBM use 0014 20 Signed 4 HALALET ALET 0018 24 Character 8 HALIASIT I-ASIT associated with .HALALET 0020 32 Signed 4 HALNEXT (0) Next entry in the list Length equate 00000004 HALSIZE (*-HALBK+7)/8 Length of HALBK in DWs
HALBK Storage Layout
*** HALBK - Host-ART lookaside block * * +-------------------------------------------------------+ * 0 | HALHDR | * | | * +-------------------------------------------------------+ * 10 | HALENTRY | * | | * +-------------------------------------------------------+ * 20 * *** HALBK - Host-ART lookaside block *** Overlay for HALHDR in HALBK * * +---------------------------+---------------------------+ * 0 | HALMXENT | HALVMDBK | * +---------------------------+---------------------------+ * 8 |///////////////////////////////////////////////////////| * +-------------------------------------------------------+ * 10 * *** Overlay for HALHDR in HALBK *** Overlay for HALENTRY in HALBK * * +------+--------------------+---------------------------+ * 10 |:STATE|////////////////////| HALALET | * +------+--------------------+---------------------------+ * 18 | HALIASIT | * +-------------------------------------------------------+ * *** Overlay for HALENTRY in HALBK
HALBK Cross Reference
Symbol Dspl Value -------------- ---- ----- * 0010 00000000 HALALET 0014 HALENTRY 0010 HALHDR 0000 HALIASIT 0018 HALINVAL 0010 00000000 HALMXENT 0000 HALNEXT 0020 HALSIZE 0020 00000004 HALSTATE 0010 HALVALID 0010 00000001 HALVMDBK 0004
Last updated on 29 Mar 2001 at 15:51:19 EDT.
Copyright IBM Corporation, 1990, 2001