dmasampledevice.cpp

WDM设备驱动程序开发(武安河)配套光盘实例源码。DMA编程实例。

// DMASampleDevice.cpp
// Implementation of DMASampleDevice device class
//
// Generated by DriverWizard version DriverStudio 2.6.0 (Build 336)
// Requires Compuware's DriverWorks classes
//

#pragma warning(disable:4065) // Allow switch statement with no cases
		  
#include <vdw.h>
#include "..\DMASampleDeviceinterface.h"

#include "DMASample.h"
#include "DMASampleDevice.h"

#pragma hdrstop("DMASample.pch")

KTrace t("DMASample");

GUID DMASampleDevice_Guid = DMASampleDevice_CLASS_GUID;

DMASampleDevice::DMASampleDevice(PDEVICE_OBJECT Pdo, ULONG Unit) :
	KPnpDevice(Pdo, &DMASampleDevice_Guid)
{

	// Check constructor status
    if ( ! NT_SUCCESS(m_ConstructorStatus) )
	{
	    return;
	}

	// Remember our unit number
	m_Unit = Unit;

	// Initialize the lower device
	m_Lower.Initialize(this, Pdo);

    // Inform the base class of the lower edge device object
	SetLowerDevice(&m_Lower);

	// Initialize the PnP Policy settings to the "standard" policy
	SetPnpPolicy();

}

DMASampleDevice::~DMASampleDevice()
{
}

NTSTATUS DMASampleDevice::DefaultPnp(KIrp I) 
{
	I.ForceReuseOfCurrentStackLocationInCalldown();
	return m_Lower.PnpCall(this, I);
}

NTSTATUS DMASampleDevice::DefaultPower(KIrp I) 
{
	I.IndicatePowerIrpProcessed();
	I.CopyParametersDown();
	return m_Lower.PnpPowerCall(this, I);
}

NTSTATUS DMASampleDevice::SystemControl(KIrp I) 
{
	I.ForceReuseOfCurrentStackLocationInCalldown();
	return m_Lower.PnpCall(this, I);
}

VOID DMASampleDevice::Invalidate()
{
	// It is not necessary to release the system resource for the DMA adapter
	// object, since NT provides no mechanism for this.
	m_Buffer.Invalidate();
}

NTSTATUS DMASampleDevice::OnStartDevice(KIrp I)
{
	NTSTATUS status = STATUS_SUCCESS;

	I.Information() = 0;

	// The default Pnp policy has already cleared the IRP with the lower device
	// Initialize the physical device object.

	// Get the list of raw resources from the IRP
	PCM_RESOURCE_LIST pResListRaw = I.AllocatedResources();
	// Get the list of translated resources from the IRP
	PCM_RESOURCE_LIST pResListTranslated = I.TranslatedResources();

// TODO:	Check to ensure that the following parameters are correct for your hardware
//
#define MAX_DMA_LENGTH	0x100000	// 0x100000 is 1 MB

	// Initialize the device descriptor for the DMA object using the assigned resource
	DEVICE_DESCRIPTION dd;
	RtlZeroMemory(&dd, sizeof(dd));
	dd.Version = DEVICE_DESCRIPTION_VERSION;
	dd.Master = TRUE;
	dd.ScatterGather = FALSE;
	dd.DemandMode = TRUE;
	dd.AutoInitialize = FALSE;
	dd.Dma32BitAddresses = TRUE;
	dd.IgnoreCount = FALSE;
	dd.DmaChannel = 0;
	dd.InterfaceType = PCIBus;
	dd.DmaWidth = Width32Bits;	// PCI default width
	dd.DmaSpeed = Compatible;
	dd.MaximumLength = MAX_DMA_LENGTH;

	// Initialize the DMA adapter object
	m_Dma.Initialize(&dd, m_Lower.TopOfStack());

	m_Buffer.Initialize(&m_Dma,1024);

	return status;
}

NTSTATUS DMASampleDevice::OnStopDevice(KIrp I)
{
	// Device stopped, release the system resources.
	Invalidate();

	return STATUS_SUCCESS;
}

NTSTATUS DMASampleDevice::OnRemoveDevice(KIrp I)
{
	// Device removed, release the system resources.
	Invalidate();

	return STATUS_SUCCESS;
}

VOID DMASampleDevice::CancelQueuedIrp(KIrp I)
{
	KDeviceQueue dq(DeviceQueue());

	// Test if the IRP is the current IRP.
	if ( (PIRP)I == CurrentIrp() )
	{
		CurrentIrp() = NULL;
		CancelSpinLock::Release(I.CancelIrql());
	    I.Information() = 0;
		I.Status() = STATUS_CANCELLED;
		PnpNextIrp(I);
	}
	// See if the IRP can be removed from the device queue.
	else if (dq.RemoveSpecificEntry(I))
	{
		CancelSpinLock::Release(I.CancelIrql());
	    I.Information() = 0;
		I.PnpComplete(this, STATUS_CANCELLED);
	}
	else
	{
		CancelSpinLock::Release(I.CancelIrql());
	}
}

VOID DMASampleDevice::StartIo(KIrp I)
{
	if ( !I.TestAndSetCancelRoutine(
		LinkTo(CancelQueuedIrp),
		NULL,
		CurrentIrp()) )
	{
		return;
	}

	switch (I.MajorFunction())
	{
		case IRP_MJ_READ:
			SerialRead(I);
			break;
		case IRP_MJ_WRITE:
			SerialWrite(I);
			break;
		default:
			ASSERT(FALSE);
			PnpNextIrp(I);
			break;
	}
}

NTSTATUS DMASampleDevice::Create(KIrp I)
{
	NTSTATUS status;

	status = I.PnpComplete(this, STATUS_SUCCESS, IO_NO_INCREMENT);

	return status;
}

NTSTATUS DMASampleDevice::Close(KIrp I)
{
	NTSTATUS status;

	status = I.PnpComplete(this, STATUS_SUCCESS, IO_NO_INCREMENT);

    return status;
}

NTSTATUS DMASampleDevice::CleanUp(KIrp I)
{
    KDeviceQueue dq(DeviceQueue());
	dq.PnpCleanUp(this, I.FileObject());
	return I.PnpComplete(this, STATUS_SUCCESS);
}

void DMASampleDevice::SerialRead(KIrp I)
{
	NTSTATUS status		= STATUS_SUCCESS;

	m_CurrentTransfer = new(NonPagedPool) KDmaTransfer(this, &m_Dma);

	if ( m_CurrentTransfer == NULL )
	{
		status = STATUS_INSUFFICIENT_RESOURCES;
		DbgPrint("unable to allocate transfer object: %x\n", status);

		I.Information() = 0;
		I.Status() = status;
		PnpNextIrp(I);
	}

	status = m_CurrentTransfer->Initiate(
		this,
		&m_Dma,
		I.Mdl(),
		(I.MajorFunction() == IRP_MJ_READ) ? FromDeviceToMemory : FromMemoryToDevice,
		LinkTo(OnDmaReady),
		&m_Buffer
		);	//运行Initiate后，系统将首次调用OnDmaReady
	// If the transfer cannot be initiated, complete it with an error status.
	if ( ! NT_SUCCESS(status) )
	{
		DbgPrint("unable to initiate transfer: %x\n", status);

		delete m_CurrentTransfer;
		m_CurrentTransfer = NULL;

		I.Information() = 0;
		I.Status() = status;
		PnpNextIrp(I);
	}
}

NTSTATUS DMASampleDevice::Read(KIrp I) 
{
	if (I.ReadSize() == 0)
	{
		I.Information() = 0;
		return I.PnpComplete(this, STATUS_SUCCESS);
	}

	return QueueIrp(I, LinkTo(CancelQueuedIrp));
}

void DMASampleDevice::SerialWrite(KIrp I)
{
	NTSTATUS status		= STATUS_SUCCESS;

	// Declare a memory object
	KMemory Mem(I.Mdl());
	// Use the memory object to create a pointer to the caller's buffer
	PVOID	pSBuffer	= Mem.MapToSystemSpace();
	//应用程序输出缓冲区在内核模式中的地址

	PVOID	pDBuffer	= m_Buffer.VirtualAddress();//公用缓冲区的内核模式地址
	ULONG   dwTotalSize = I.WriteSize(CURRENT);	//所写数据的字节长度
	ULONG   dwBytesSent = 0;

	if (dwTotalSize > 1024) dwBytesSent = 1024;
	else dwBytesSent = dwTotalSize;
	RtlCopyMemory(pDBuffer, pSBuffer, dwBytesSent);
	//将应用程序写缓冲区数据拷贝至公用缓冲区，模仿DMA操作

	I.Information() = dwBytesSent;
	I.Status() = status;

	PnpNextIrp(I);
}

NTSTATUS DMASampleDevice::Write(KIrp I) 
{
	if (I.WriteSize() == 0)
	{
		I.Information() = 0;
		return I.PnpComplete(this, STATUS_SUCCESS);
	}

	return QueueIrp(I, LinkTo(CancelQueuedIrp));
}

VOID DMASampleDevice::IsrProxyTimer(PVOID Arg1, PVOID Arg2)
{
	m_CurrentTransfer->Continue(UseTransferSize);
	//当DMA传输完成后，将产生中断，运行Continue，系统将再次调用OnDmaReady
}

VOID DMASampleDevice::StartDMA(ULONG PAddress,ULONG NBytes)
{
	// Normally at this point we would use the transfer descriptors to set up
	// the hardware for the next DMA.  Once the transfer was setup, it would be
	// initiated and once the transfer was complete, the interrupt would be
	// signaled. We simply set up a timer to emmulate this process.

	//由于并不存在实际的DMA操作，产生不了DMA中断，只好启动一个1秒的定时器，
	//来模拟DMA中断
	LONGLONG DueTime = -10000000;		// 100ns units (1sec)
	m_IsrProxyTimer.Set(
		DueTime,
		LinkTo(IsrProxyTimer),
		this
		);
}

VOID DMASampleDevice::OnDmaReady(KDmaTransfer* pXfer, KIrp I)
{
	t << "Entering OnDmaReady\n";

	// All KDmaTransfer callbacks must first check to see if there are any bytes
	// left to transfer.
	if (pXfer->BytesRemaining() == 0)
	{	// 一次DMA传输完成
		// If there are no bytes left to transfer, the callback must call
		// Terminate(). Then it completes the IRP with STATUS_SUCCESS.
		t << "terminating transfer\n";
		pXfer->Terminate();
	
		I.Information() = I.ReadSize(CURRENT);
		I.Status() = STATUS_SUCCESS;
		PnpNextIrp(I);

		m_CurrentTransfer = NULL;
		delete pXfer;
		return;
	}

	// We must get the descriptor for the physical memory location for
	// the DMA transfer.

	PTRANSFER_DESCRIPTOR ptd;

	while (pXfer->SequenceTransferDescriptors(&ptd)) {
		// program the h/w using  ppTD
		t << "Physical address 0x" << ptd->td_PhysAddr.LowPart << ". Length is 0x"
			<< ptd->td_Length << "." << EOL;
	}

	// If this is the first time through, then start the DMA going.
	// We only want to do this ONCE for a given Read transfer.  That
	// way, our data will be collected smoothly, without interruptions
	// or dropouts.
	if ((ULONG) pXfer->BytesRemaining() == I.ReadSize())
		StartDMA(ptd->td_PhysAddr.LowPart,ptd->td_Length);
	//首次调用OnDmaReady，应启动DMA传输
}