Type ASSEMBLE
Source Lines : 439
Fixes Applied : 7
Most Recent Version : Thursday, December 7, 1978
Last Fix ID : [HRC039DK]
Module
DMKVDR
Function
TO PERFORM THE NECESSARY FUNCTIONS TO RELEASE A REAL OR
VIRTUAL DEVICE FROM A VIRTUAL MACHINE.
Attributes
REENTRANT, PAGEABLE, CALLED VIA SVC
Operation
1. A CALL IS MADE TO DMKCFPRD TO RESET THE DEVICE AND
CLEAR ANY ACTIVE IOBLOK OR PENDING I/O INTERRUPTS.
2. CHECKS ARE THEN MADE TO SEE IF THE DEVICE IS DEDICATED,
A DISK STORAGE DEVICE, A UNIT RECORD DEVICE, A SPECIAL
DEVICE, OR A CONSOLE DEVICE. (IF NONE OF THESE, AN ABEND
VIA SVC 0 IS GENERATED, INDICATING AN INTERNAL CODING ERROR.)
3. DEDICATED DEVICE: THE RDEVBLOK ADDRESS IS OBTAINED FROM
THE VDEVBLOK, AND ITS ADDRESS IS THEN CLEARED. IF THE DEVICE
IS A TAPE, AN IOBLOK TO REWIND AND UNLOAD THE TAPE IS BUILT,
AND DMKIOSQR IS CALLED TO START THE OPERATION. IN ANY EVENT,
THE DMKACODV ACCOUNTING ROUTINE IS CALLED, THE DEDICATED FLAG
BITS IN THE RDEVBLOK AND VDEVBLOK ARE CLEARED, THE OPERATOR IS
SENT A MESSAGE THAT THE DEVICE HAS BEEN RELEASED (BY WHAT
USER), AND RETURN IS MADE.
4. DISK STORAGE DEVICE: THE RDEVBLOK ADDRESS IS OBTAINED
FROM THE VDEVBLOK, AND ITS ADDRESS (VDEVREAL) IS THEN CLEARED.
IF THE DEVICE IS A T-DISK, DMKACODV IS CALLED TO BUILD AN
ACCOUNTING RECORD. THEN DMKTDKRL IS CALLED TO RETURN THE
T-DISK SPACE TO THE SYSTEM, AND RETURN IS MADE. IF NOT, THE
COUNT OF LINKS TO THE DISK IN THE RDEVBLOK IS DECREMENTED, AND
THE CHAIN OF LINKS TO THE DISK ACCESSIBLE VIA THE VDEVBLOK IS
ADJUSTED TO DELETE THE CALLER'S USERID. RETURN IS THEN MADE.
5. UNIT RECORD DEVICE: IF NO FILES ARE OPEN, RETURN IS MADE.
IF YES, THEN DMKVSPCO IS CALLED TO CLOSE THE PRINTER OR PUNCH,
OR DMKVSPCR IS CALLED TO CLOSE THE READER, AND RETURN IS MADE.
6. SPECIAL DEVICE: IF THE DEVICE IA A VIRTUAL CHANNEL-
TO-CHANNEL ADAPTER (CTCA), DMKVCARS IS CALLED TO RESET THE
UNIT AND DISCONNECT IT FROM ANOTHER ADAPTER, IF NEEDED.
IF IT IS NOT A VIRTUAL CTCA, RETURN IS IMMEDIATE.
7. CONSOLE DEVICE: IF THE DEVICE IS NOT A 1052 TYPE DEVICE,
EXIT IS IMMEDIATELY MADE TO THE CALLER. IF CONSOLE SPOOL
FILE IS ACTIVE; CALL DMKVSPCO TO CLOSE THE FILE.
RETURN IS THEN MADE TO THE CALLER.
Calls to Other Routines
DMKCFPRD
DMKACODV
DMKCVTBH
DMKQCNWT
DMKFREE
DMKSCNRD
DMKSCNRN
DMKIOSQR
DMKTDKRL
DMKVSPCR
DMKVSPCO
DMKVCARS
DMKFRET
DMKPTRPW