DVIOP | Back to Index page |
Prolog Control Block Contents DVIOP DSECT DVIENTRY DSECT Storage Layout Cross Reference (Contains links to field and bit definitions) |
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DVIOP Prolog | Top of page |
NAME : HCPDVIOP DESCRIPTION: DASD Virtual I/O Parameter List DSECT : DVIOP FUNCTION : Contains information specific to DASD virtual I/O requests, including minidisk caching interface parameters. LOCATED BY : DVCOPPTR in the DVCPL control block. The DVCPL control block is located by DBCDVCPL located in the DBCWK control block. All CMS block i/o handlers (Diag X'18', Diag X'A4', Diag X'250' and *BLOCKIO) have a register pointing to the DBCWK block. CREATED BY : HCPDPCUT macro (for diagnose X'A4', *BLOCKIO, diagnose x'18', and diagnose x'250') (created in module HCPDBC) HCPZIW (for CP i/o to CMS files) DELETED BY : When used as by *BLOCKIO, Diagnose x'A4', Diagnose X'18', and Diagnose x'250', it is deleted by HCPDPSCU. RELOCATION CONSIDERATIONS : None NOTES : - This parameter list is used as a communication block between virtual I/O (diagnoses and *BLOCKIO), the channel program builder (HCPDPSRW or HCPDCCWB) and the cache back end processor (HCPBIUCB). - It is used as the common descriptor for an I/O request through *BLOCKIO, diagnose X'A4' diagnose X'18', and diagnose x'250'. It also is used as the common descriptor for an I/O request to read records from a CMS file. - The physical parameter list contains a DVIOP header, which points to a variable sized linked list of DVIENTRYs, one per DASD record. - The DVIOP contains general information about the request and information common to all blocks associated with this DVIOP. A DVIOP represents one i/o to be performed. A DVIENTRY represents one block or record that is part of that i/o. - The cache back end processor will process up to one DVIOP at a time (or just a portion of that DVIOP if requested) and relinquish access to all tracks in the cache for a given DVIOP. Any cache invalidation required is also performed. |
DVIOP Control Block Content | Top of page |
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DVIOP Storage Layout | Top of page |
*** DVIOP - DASD Virtual I/O Parameter List * * +---------------------------+---------------------------+ * 0 | DVIOPNXT | DVIENPTR | * +---------------------------+-------------+-------------+ * 8 | DVIENDEN | DVIDEVNO | DVICYLNO | * +------+------+------+------+-------------+-------------+ * 10 |:PLFLG|:OPRC |:HDROP|//////| DVICHPRG | * +------+------+------+------+---------------------------+ * 18 | DVICHSIZ | DVIBLKSZ | DVITRIED | * +-------------+-------------+-------------+-------------+ * 20 | DVIBLKCT | DVIECYL |/////////////| * +---------------------------+-------------+-------------+ * 28 * *** DVIOP - DASD Virtual I/O Parameter List *** DVIENTRY - DASD Virtual I/O Parameter List * * +---------------------------+---------------------------+ * 0 | DVINEXT | DVIPREV | * +------+------+------+------+-------------+------+------+ * 8 |:IORC |:CCWFG|:STSEC|:RWFLG| DVICCFLD |:HED1 |:HED2 | * +------+------+------+------+-------------+------+------+ * 10 |:RECNO|:PRVDD|/////////////| DVIHDARG | DVIBLKOV | * +------+------+-------------+-------------+-------------+ * 18 | DVIIDAWA | * +-------------------------------------------------------+ * 20 | DVIIDAWB | * +---------------------------+---------------------------+ * 28 | DVIPLPTR | DVIRTRAK | * +---------------------------+---------------------------+ * 30 | DVIFTKEY | DVIDVTRK | * +---------------------------+---------------------------+ * 38 | DVIASITA |///////////////////////////| * +---------------------------+---------------------------+ * 40 * *** DVIENTRY - DASD Virtual I/O Parameter List |
DVIOP Cross Reference | Top of page |
Symbol Dspl Value -------------- ---- ----- DVIADCPE 0008 0000002C DVIALSPE 0008 00000024 DVIALTRE 0008 00000020 DVIASITA 0038 DVIBDBLK 0008 00000004 DVIBDBUF 0008 00000008 DVIBDPLA 0008 00000038 DVIBDPLC 0008 0000003C DVIBDPLG 0008 00000040 DVIBDPLP 0008 00000034 DVIBDSVC 0008 00000010 DVIBLKCT 0020 DVIBLKID 000E DVIBLKOV 0016 DVIBLKSZ 001A DVIBLLEN 0040 00000040 DVICCFLD 000C DVICCWFG 0009 DVICHPRG 0014 DVICHSIZ 0018 DVICYLNO 000E DVIDEVNO 000C DVIDIA18 0010 10 DVIDVCYL 000C DVIDVTRK 0034 DVIDWLEN 0040 00000040 DVIDWSIZ 0026 00000005 DVID250 0010 02 DVIECYL 0024 DVIENDEN 0008 DVIENPTR 0004 DVIFAIL 0012 20 DVIFBABN 000C DVIFBALR 0010 01 DVIFTKEY 0030 DVIHDARG 0014 DVIHDROP 0012 DVIHEDNO 000E DVIHED1 000E DVIHED2 000F DVIHED2R 000F DVIIDAWA 0018 DVIIDAWB 0020 DVIIDLEN 0010 00000003 DVIIORC 0008 DVIISFBA 0010 04 DVIMXBLK 0010 08 DVINCLEN 0008 0000001C DVINEXT 0000 DVINOTPR 0008 00000030 DVIOPNXT 0000 DVIOPRC 0011 DVIOPSIZ 0026 00000028 DVIPAGER 0008 00000018 DVIPLFLG 0010 DVIPLPTR 0028 DVIPREV 0004 DVIPREXC 0008 00000014 DVIPRVDD 0011 DVIPRVSH 0011 20 DVIPRVSI 0011 40 DVIPRVSS 0011 80 DVIRBILD 0010 40 DVIRCOK 0008 00000000 DVIRDINS 0010 80 DVIRDONL 0008 0000000C DVIREAD 0012 40 DVIRECNO 0010 DVIRTRAK 002C DVIRWFLG 000B DVISEVER 0008 000000FF DVISILIB 0010 20 DVISPECE 0008 00000028 DVISRCID 000C DVISTSEC 000A DVITRIED 001C DVIWRITE 0012 80 |
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