I-:Ij ..... Ul t1 (1) m "0 t1 0 \,Q t1 I» 51 H t:I ci' (1) t1 t1 C "C ci' I» t:I PI ...... ..... t:I \Q PSA • This is the entry point W to refh,ct SVC interrupts
(when DMKSVC could not reflect it) and to reflect privileqed instructions that
cannot be simulated by
DMKPRVLG Invalid operation code
is in GR O. The VMINST field of the VMBLOK contains
the image of the privileged instruction that caused the
interrupt • Program I nterwpt ----------------Process
Determine machine mode and cause of interrupt If in supervisor mode, go to DMKDMPDK to take CP dump ---..J------------- . ...r-..... If invalid operation, go to DMKPRGRF routine ••••••• ------- If recognizable privileged instruction, simulate it If privileged instruction is not recognized,
issue SVC 0 and dump CP If pag,ng exception, call DMKPTRAN to
bring page with requested address
into real storage. If proqram interrupt occurs in virtual problem mode, reflect the
interrupt back to the virtual machine _______ . ___ . _____ VMBLOI<: t VMINSTj SWPTABLE Virtual Storage OUTPUT ---------------.-, VMBLOI<: [VM_ r User's Page 0

.... I .... N IoQ 0 g .., (1) ..,.J tJI III ... III "0 '" PI W IoQ .....a .... 0 IoQ en "cS en c+ (D • I:"" 0 IoQ .... n PI "0 t1 0 t.7" ..... (D • t::t (D c+ (D t1 • .... t:f I» c+ .... 0 I I ... 0 ..... d • (1) .... INPUT------------------------__ GR 2 REOUEST GPRl CORTABLE I Virtual Address
PAGTABLE PAGCORE real page
address INPUT ------- __ PAGING DEVICE tit Bits defined for CORFLAG CORIOLCK EOU X'SO' Page locked for 1/0 CORCFLCK EOU X'40' Page locked by console function CORFLUSH EOU X'20' Page is in flush list CORFREE EOU X'10' Page is in free list CORSHARE EOU X'OS' Page is shared CORRSV EOU X'04' Page is reserved CORDISA EOU X'01' Page disabled - not available • Request For
Real Storage ....-------- .. ----- PROCI:SS ------, «It Bits defined for SWPFLAG - SWPTRANS EOU X'80' SWPRECMP EOU X'40' SWPALLOC EOU X'20' SWPSHR EOU X'10' SWPREFl EOU X'OS' SWPCHGl EOU X '04' SWPREF2 EOU X'02' SWPCHG2 EOU X'01' Translate address Is requested page already in sto, age? • i Determine page selection ,---- __ Is page available from lists? {ES • i YES OUTPUT--------, PAGING DEVICE Rei ease pages Allocate DASD space =====1:==:;:==:=::::':: Schedu Ie page 1/0 Mark page free
Lock - if requested
Form address
GR 2 Real Address
Return to requester ................ RITURN Page in transit
Page permanently assigned
Page enqueued for allocation Page shared
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