Type ASSEMBLE
Source Lines : 736
Fixes Applied : 4
Most Recent Version : Thursday, December 14, 1978
Last Fix ID : [HRC013DK]
Module
DMKPRG
Function
TO PROVIDE THE PROPER HANDLING FOR VARIOUS TYPES OF
PROGRAM INTERRUPTS WHICH MAY OCCUR.
Attributes
REUSEABLE, RESIDENT, FIRST-LEVEL INTERRUPT HANDLER
Operation
DMKPRGIN DETERMINES THE MODE OF THE MACHINE (PROBLEM OR
SUPERVISOR STATE), AND THE CAUSE OF THE PROGRAM INTERRUPTION
IF A PROGRAM INTERRUPT OCCURRED WITH THE MACHINE IN THE
SUPERVISOR STATE, REGISTERS ARE STORED IN THE DMKDMPGR AREA,
AND CONTROL IS TRANSFERRED TO DMKDMPDK TO DUMP THE
MACHINE.
IF THE INTERRUPT WAS CAUSED BY A PRIVILEGED OR INVALID
OPERATION, DMKPRGIN TRANSFERS TO DMKPRVLG FOR SIMULATION.
ANY PROGRAM INTERRUPT RECEIVED WHILE THE VIRTUAL MACHINE
IS IN PROBLEM STATE IS REFLECTED TO THE VIRTUAL MACHINE.
IF ANY PROGRAM INTERRUPT OCCURRS SUCH THAT THE OLD PSW
ADDRESS, MINUS THE INSTRUCTION LENGTH CODE, EQUALS THE
ADDRESS IN THE PROGRAM NEW PSW, A WARNING MESSAGE:
DMKPRG453W CP ENTERED; PROGRAM INTERRUPT LOOP
IS ISSUED, THE PSW'S ARE EXCHANGED AS IF THE INTERRUPT
WERE TO BE REFLECTED, AND THE VIRTUAL MACHINE IS PLACED
IN CP CONSOLE FUNCTION MODE VIA A CALL TO DMKCFMBK.
A PAGE EXCEPTION INTERRUPT IS HANDLED VIA A CALL TO
DMKPTRAN TO BRING IN THE REQUIRED VIRTUAL STORAGE PAGE.
AN ADDRESSING EXCEPTION IS GENERATED IF THE REFERENCED
ADDRESS IS OUTSIDE OF VIRTUAL STORAGE. IF THE INTERRUPT
WAS FOR AN EC-MODE VIRTUAL MACHINE RUNNING IN VIRTUAL
TRANSLATE MODE, DMKVATPX IS INVOKED VIA GOTO.
IF A VIRTUAL ECMODE MACHINE HAS REQUESTED PSEUDO PAGE FAULT
HANDLING AND IS ENABLED, A PSEUDO PAGE FAULT MAY BE GENER-
ATED IF THE 2ND LEVEL MEMORY PAGE IS NOT AVAILABLE. THE PAGE
FAULT IS HANDLED VIA A GOTO TO DMKVATPF.
OR AN ECMODE MACHINE RUNNING NON-TRANSLATE IS
TREATED IN THE SAME MANNER AS A PAGE EXCEPTION
INDICATES A VIRTUAL ADDRESSING ERROR HAS BEEN MADE, AND
AN ADDRESSING EXCEPTION IS GENERATED FOR THE VIRTUAL
IF THE VIRTUAL MACHINE IS RUNNING IN VIRTUAL
TRANSLATE MODE, DMKVATSX IS INVOKED VIA GOTO TO FIELD THE
INTERRUPT.
THE DMKPRGRF ENTRY POINT (INVOKED FROM DMKPSASV) PERFORMS
THE NECESSARY FUNCTIONS TO REFLECT AN SVC-INTERRUPT TO
THE VIRTUAL MACHINE (SEE LATER SECTION FOR DETAILS).
THE DMKPRGSM ENTRY POINT IS INVOKED VIA GOTO WHENEVER
A PROGRAM INTERRUPT MUST BE GENERATED FOR A VIRTUAL
MACHINE. THE VIRTUAL OLD PSW AND ILC DATA IS CONTAINED
IN THE VMBLOK - VMPSW AND VMPRGIL FIELDS. EXIT IS VIA
GOTO DMKDSPB.
Calls to Other Routines
DMKPTRAN - TO HANDLE PAGING EXCEPTION
DMKPRVLG - TO HANDLE PRIVILEGED INSTRUCTIONS
DMKDSPCH - TO DISPATCH A USER
DMKCFMBK - TO PLACE A VIRTUAL MACHINE IN CP CONSOLE MODE
DMKQCNWT - TO TYPE WARNING MESSAGE AT USER TERMINAL
DMKDMPDK - TO DUMP CORE IF PROGRAM INTERRUPT FROM CP
DMKVATPX - TO PROCESS PAGING EXCEPTION FOR V370R
DMKVATSX - TO PROCESS SEGMENT EXCEPTION FOR V370R
DMKVATPF - TO SIMULATE PSEUDO PAGE FAULT FOR V370R
DMKDSPB - TO NEW PSW ENTRY IN DISPATCHER
DMKDSPA - TO (POTENTIALLY) FAST RE-DISPATCH CURRENT USER
DMKPERIL -