isr.c

老外写的一个相当不错的虚拟显示器驱动

#include "Driver.h"


/*************************************************************************************************/
BOOLEAN EnableIRQ(IN PVOID SynchronizeContext)
{
	PFDO_DATA deviceExtension = (PFDO_DATA)SynchronizeContext;

	// TODO: Enable IRQ in the hardware.

	return TRUE;
}


/*************************************************************************************************/
BOOLEAN DisableIRQ(IN PVOID SynchronizeContext)
{
	PFDO_DATA deviceExtension = (PFDO_DATA)SynchronizeContext;

	// TODO: Disable IRQ in the hardware.

	return TRUE;
}


/*************************************************************************************************/
BOOLEAN IsrRoutine(IN PKINTERRUPT Interrupt, IN PVOID ServiceContext)
{
    PFDO_DATA deviceExtension = (PFDO_DATA)ServiceContext;
	
	// Disable further interrupts.
	DisableIRQ(deviceExtension);

	// Start DPC to handle the interrupt.
	KeInsertQueueDpc(&deviceExtension->DpcForPortIsr, NULL, NULL);

	return TRUE;
}


/*************************************************************************************************/
VOID DpcForIsrRoutine(PKDPC pDpc, PVOID pContext, PVOID pArg1, PVOID pArg2)
{
    PFDO_DATA deviceExtension = (PFDO_DATA)pContext;
	PIO_STACK_LOCATION IrpStack;
	PIRP Irp;
	PUCHAR Buffer;
	ULONG NumberOfBytesPutInTheBuffer;

	// Get an IRP from the queue.
	Irp = IoCsqRemoveNextIrp(&deviceExtension->CSReadQueue, NULL);

	if (Irp != NULL)
	{
		IrpStack = IoGetCurrentIrpStackLocation(Irp);

		// Get access to user buffer.
		Buffer = (PUCHAR)MmGetSystemAddressForMdl(Irp->MdlAddress);

		// Put something into the buffer. The size of the buffer is in IrpStack->Parameters.Read.Length
		NumberOfBytesPutInTheBuffer = IrpStack->Parameters.Read.Length;

		RtlFillMemory(Buffer, NumberOfBytesPutInTheBuffer, 0xaa);

		// Complete the IRP and return the number of bytes we actually put into the buffer.
		Irp->IoStatus.Information = NumberOfBytesPutInTheBuffer;
		Irp->IoStatus.Status = STATUS_SUCCESS;
		
		KeFlushIoBuffers(Irp->MdlAddress, TRUE, FALSE);
		IoCompleteRequest(Irp, IO_NO_INCREMENT);
	}

	// DCP routine finished, enable interrupts again.
	EnableIRQ(deviceExtension);
}