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include vpicd.inc
 
mov     eax, IRQHand    ; IRQ handle
mov     ebx, VM         ; current VM handle
VxDcall VPICD_Set_Int_Request
 
The VPICD_Set_Int_Request service sets a virtual interrupt request for the
specified IRQ and virtual machine. Setting the request causes the system to
simulate an interrupt. Although the simulation may occur immediately, in
many cases it may not until a later point in time.
 
Parameter  Description
────────────────────────────────────────────────────────────────────────────
 
IRQHand    Specifies the handle identifying the IRQ to set.
 
VM         Specifies the handle identifying the virtual machine.
 
Return Value
 
This service has no return value.
 
Comments
 
The interrupt is not simulated immediately if any of the following
conditions are present:
 
♦  The virtual machine has interrupts disabled
 
♦  The virtual machine has masked the IRQ
 
♦  A higher priority virtual IRQ is in service
 
♦  The virtual machine is suspended, or not able to run
 
However, since the interrupt may be simulated immediately, a virtual device
that has a virtual interrupt handler must be able to handle a call to the
handler before this service returns.
 
Setting an interrupt request does not guarantee that the interrupt will be
simulated. For example, if the VM has masked the interrupt and never unmasks
it, the interrupt is never simulated. Also, a call to the
VPICD_Clear_Int_Request service made before the virtual interrupt is
simulated prevents the interrupt simulation.
 
The virtual VPIC device simulates a level-triggered PIC. This means that
once a virtual EOI occurs, another interrupt will be simulated immediately
unless the virtual interrupt request is cleared.
 
Uses
 
Flags
 
See Also
 
VPICD_Clear_Int_Request
 
 
                                      ♦