Programming Interface Information:
This information is NOT intended to be
used as Programming Interfaces of z/VM. |
BKIBK
Control Block Contents
BKIBK DSECT
Cross Reference (Contains links to field and bit definitions)
BKIBK Prolog
NAME : HCPBKIBK DESCRIPTION: Block I/O Block for DIAGNOSE X'250' DSECT : BKIBK FUNCTION : Main control block for the DIAGNOSE X'250' function; all other information can be found from this block. LOCATED BY : VDEVBKIA CREATED BY : HCPBICIN, during the initialization of the DIAGNOSE X'250' block I/O environment DELETED BY : HCPBICRE, during the removal of the DIAGNOSE X'250' block I/O environment SERIALIZED : The block I/O block lock, BKILOCK. COMMENTS : Refer to the description of the VDEVBKIA field for information on the serialization for pointing to this block from the appropriate VDEV. There is one BKIBK for each VDEV for which a DIAGNOSE X'250' environment is initialized.
BKIBK Control Block Content
BKIBK DSECT
Hex Dec Type/Val Lng Label (dup) Comments ---- ---- --------- ---- -------------- -------- 0000 0 Structure BKIBK Block I/O Block for DIAGNOSE X'250' 0000 0 Bitstring 1 BKISTAT Block I/O function status .1.. .... BKIRESET X'40' A reset operation is pending. Note: this flag is set for serviceability - it is not checked, since BKIRMPD is always set as well by the time reset/remove status needs to be recognized. 0001 1 Bitstring 1 BKIFLAGS Device status flags .... .1.. BKIRMPD X'04' A REMOVE request is pending .... ...1 BKIDEVRD X'01' Virtual device is read only 0002 2 Bitstring 2 * Reserved for IBM use 0004 4 Signed 4 BKIOFFCP CP offset for CMS disk BKIDBCCT indicates processes in HCPDBC. It is used to indicate that outstanding i/o is being done maybe by the minidisk cache i/o handler (HCPFTUAD). Thus BKIDBIRQ and BKIDBCCT BOTH must be 0 to indicate there is no outstanding Diag 250 for this device. 0008 8 Signed 4 BKIDBCCT Count of processes in HCPDBC 000C 12 Signed 4 BKIDBIRQ Chain of outstanding DBIRQs 0010 16 Signed 4 BKIDBCWK Chain of outstanding i/o requests 0014 20 Signed 4 BKIBLKSZ Block size of user's disk 0018 24 Signed 4 BKIOFFST User's requested offset 001C 28 Signed 2 BKIVDEVN Virtual device number 001E 30 Bitstring 2 * Reserved for future IBM use 0020 32 Signed 4 BKISTART User's starting block 0024 36 Signed 4 BKIEND User's ending block 0028 40 Signed 4 BKIVDEVA Virtual device block address 002C 44 Signed 4 BKIDINFO Address of device information 0030 48 Signed 4 BKISAVBK Caller's save block 0034 52 Signed 4 BKIRMVMD Address of the VMDBK on which .the RESET or REMOVE was .issued. 0038 56 Signed 4 * Reserved for IBM use 0040 64 Dbl-Word 8 BKILOCK (3) BKIBK lock 0058 88 Signed 4 * Reserved for IBM use 005C 92 Signed 4 * Reserved for IBM use 0060 96 Signed 4 * Reserved for IBM Use 0064 100 Signed 4 * Reserved for IBM use 0000000D BKISIZE (*-BKIBK+7)/8 Length of BKIBK in DWs
BKIBK Storage Layout
*** BKIBK - Block I/O Block for DIAGNOSE X'250' * * +------+------+-------------+---------------------------+ * 0 |:STAT |:FLAGS|/////////////| BKIOFFCP | * +------+------+-------------+---------------------------+ * 8 | BKIDBCCT | BKIDBIRQ | * +---------------------------+---------------------------+ * 10 | BKIDBCWK | BKIBLKSZ | * +---------------------------+-------------+-------------+ * 18 | BKIOFFST | BKIVDEVN |/////////////| * +---------------------------+-------------+-------------+ * 20 | BKISTART | BKIEND | * +---------------------------+---------------------------+ * 28 | BKIVDEVA | BKIDINFO | * +---------------------------+---------------------------+ * 30 | BKISAVBK | BKIRMVMD | * +---------------------------+---------------------------+ * 38 |///////////////////////////|///////////////////////////| * +---------------------------+---------------------------+ * 40 | | * = BKILOCK = * | | * +---------------------------+---------------------------+ * 58 |///////////////////////////|///////////////////////////| * +---------------------------+---------------------------+ * 60 |///////////////////////////|///////////////////////////| * +---------------------------+---------------------------+ * 68 * *** BKIBK - Block I/O Block for DIAGNOSE X'250'
BKIBK Cross Reference
Symbol Dspl Value -------------- ---- ----- BKIBLKSZ 0014 BKIDBCCT 0008 BKIDBCWK 0010 BKIDBIRQ 000C BKIDEVRD 0001 01 BKIDINFO 002C BKIEND 0024 BKIFLAGS 0001 BKILOCK 0040 BKIOFFCP 0004 BKIOFFST 0018 BKIRESET 0000 40 BKIRMPD 0001 04 BKIRMVMD 0034 BKISAVBK 0030 BKISIZE 0064 0000000D BKISTART 0020 BKISTAT 0000 BKIVDEVA 0028 BKIVDEVN 001C
Last updated on 5 Jun 2001 at 12:59:36 EDT.
Copyright IBM Corporation, 1990, 2001