diff --git a/reactos/drivers/input/kbdclass/kbdclass.c b/reactos/drivers/input/kbdclass/kbdclass.c
index fb9ba439e1f..3c8158c5b37 100644
--- a/reactos/drivers/input/kbdclass/kbdclass.c
+++ b/reactos/drivers/input/kbdclass/kbdclass.c
@@ -19,6 +19,12 @@ static DRIVER_DISPATCH ClassDeviceControl;
 static DRIVER_DISPATCH IrpStub;
 static DRIVER_ADD_DEVICE ClassAddDevice;
 static DRIVER_STARTIO ClassStartIo;
+static DRIVER_CANCEL ClassCancelRoutine;
+static NTSTATUS
+HandleReadIrp(
+	IN PDEVICE_OBJECT DeviceObject,
+	IN PIRP Irp,
+	BOOLEAN IsInStartIo);
 
 static VOID NTAPI
 DriverUnload(IN PDRIVER_OBJECT DriverObject)
@@ -82,8 +88,14 @@ ClassRead(
 	IN PDEVICE_OBJECT DeviceObject,
 	IN PIRP Irp)
 {
+	PCLASS_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
+	KIRQL OldIrql;
+	NTSTATUS Status;
+
 	DPRINT("IRP_MJ_READ\n");
 
+	ASSERT(DeviceExtension->Common.IsClassDO);
+
 	if (!((PCOMMON_DEVICE_EXTENSION)DeviceObject->DeviceExtension)->IsClassDO)
 		return ForwardIrpAndForget(DeviceObject, Irp);
 
@@ -96,9 +108,10 @@ ClassRead(
 		return STATUS_BUFFER_TOO_SMALL;
 	}
 
-	IoMarkIrpPending(Irp);
-	IoStartPacket(DeviceObject, Irp, NULL, NULL);
-	return STATUS_PENDING;
+	KeAcquireSpinLock(&DeviceExtension->SpinLock, &OldIrql);
+	Status = HandleReadIrp(DeviceObject, Irp, FALSE);
+	KeReleaseSpinLock(&DeviceExtension->SpinLock, OldIrql);
+	return Status;
 }
 
 static NTSTATUS NTAPI
@@ -370,7 +383,6 @@ cleanup:
 	InitializeListHead(&DeviceExtension->ListHead);
 	KeInitializeSpinLock(&DeviceExtension->ListSpinLock);
 	KeInitializeSpinLock(&DeviceExtension->SpinLock);
-	DeviceExtension->ReadIsPending = FALSE;
 	DeviceExtension->InputCount = 0;
 	DeviceExtension->PortData = ExAllocatePoolWithTag(NonPagedPool, DeviceExtension->DriverExtension->DataQueueSize * sizeof(KEYBOARD_INPUT_DATA), CLASS_TAG);
 	if (!DeviceExtension->PortData)
@@ -454,56 +466,16 @@ ClassCallback(
 	IN OUT PULONG ConsumedCount)
 {
 	PCLASS_DEVICE_EXTENSION ClassDeviceExtension = ClassDeviceObject->DeviceExtension;
-	PIRP Irp = NULL;
 	KIRQL OldIrql;
 	SIZE_T InputCount = DataEnd - DataStart;
 	SIZE_T ReadSize;
 
+	DPRINT("ClassCallback()\n");
+
 	ASSERT(ClassDeviceExtension->Common.IsClassDO);
 
 	KeAcquireSpinLock(&ClassDeviceExtension->SpinLock, &OldIrql);
-
-	DPRINT("ClassCallback()\n");
-	/* A filter driver might have consumed all the data already; I'm
-	 * not sure if they are supposed to move the packets when they
-	 * consume them though.
-	 */
-	if (ClassDeviceExtension->ReadIsPending == TRUE && InputCount)
-	{
-		/* A read request is waiting for input, so go straight to it */
-		NTSTATUS Status;
-		SIZE_T NumberOfEntries;
-
-		Irp = ClassDeviceObject->CurrentIrp;
-		ClassDeviceObject->CurrentIrp = NULL;
-
-		NumberOfEntries = MIN(
-			InputCount,
-			IoGetCurrentIrpStackLocation(Irp)->Parameters.Read.Length / sizeof(KEYBOARD_INPUT_DATA));
-
-		Status = FillEntries(
-			ClassDeviceObject,
-			Irp,
-			DataStart,
-			NumberOfEntries);
-
-		if (NT_SUCCESS(Status))
-		{
-			/* Go to next packet and complete this request with STATUS_SUCCESS */
-			Irp->IoStatus.Status = STATUS_SUCCESS;
-			Irp->IoStatus.Information = NumberOfEntries * sizeof(KEYBOARD_INPUT_DATA);
-
-			ClassDeviceExtension->ReadIsPending = FALSE;
-
-			/* Skip the packet we just sent away */
-			DataStart += NumberOfEntries;
-			(*ConsumedCount) += (ULONG)NumberOfEntries;
-			InputCount -= NumberOfEntries;
-		}
-	}
-
-	/* If we have data from the port driver and a higher service to send the data to */
-	if (InputCount != 0)
+	if (InputCount > 0)
 	{
 		if (ClassDeviceExtension->InputCount + InputCount > ClassDeviceExtension->DriverExtension->DataQueueSize)
 		{
@@ -529,20 +501,13 @@ ClassCallback(
 		ClassDeviceExtension->InputCount += ReadSize;
 
 		(*ConsumedCount) += (ULONG)ReadSize;
-	}
-	else
-	{
-		DPRINT("ClassCallback(): no more data to process\n");
-	}
 
+		/* Complete pending IRP (if any) */
+		if (ClassDeviceExtension->PendingIrp)
+			HandleReadIrp(ClassDeviceObject, ClassDeviceExtension->PendingIrp, FALSE);
+	}
 	KeReleaseSpinLock(&ClassDeviceExtension->SpinLock, OldIrql);
 
-	if (Irp != NULL)
-	{
-		IoStartNextPacket(ClassDeviceObject, FALSE);
-		IoCompleteRequest(Irp, IO_KEYBOARD_INCREMENT);
-	}
-
 	DPRINT("Leaving ClassCallback()\n");
 	return TRUE;
 }
@@ -693,6 +658,7 @@ ClassAddDevice(
 		DPRINT("IoCreateDevice() failed with status 0x%08lx\n", Status);
 		goto cleanup;
 	}
+	IoSetStartIoAttributes(Fdo, TRUE, TRUE);
 
 	DeviceExtension = (PPORT_DEVICE_EXTENSION)Fdo->DeviceExtension;
 	RtlZeroMemory(DeviceExtension, sizeof(PORT_DEVICE_EXTENSION));
@@ -753,26 +719,61 @@ cleanup:
 }
 
 static VOID NTAPI
-ClassStartIo(
+ClassCancelRoutine(
 	IN PDEVICE_OBJECT DeviceObject,
 	IN PIRP Irp)
+{
+	PCLASS_DEVICE_EXTENSION ClassDeviceExtension = DeviceObject->DeviceExtension;
+	KIRQL OldIrql;
+	BOOLEAN wasQueued = FALSE;
+
+	DPRINT("ClassCancelRoutine(DeviceObject %p, Irp %p)\n", DeviceObject, Irp);
+
+	ASSERT(ClassDeviceExtension->Common.IsClassDO);
+
+	KeAcquireSpinLock(&ClassDeviceExtension->SpinLock, &OldIrql);
+	IoAcquireCancelSpinLock(&OldIrql);
+	if (ClassDeviceExtension->PendingIrp == Irp)
+	{
+		ClassDeviceExtension->PendingIrp = NULL;
+		wasQueued = TRUE;
+	}
+	KeReleaseSpinLock(&ClassDeviceExtension->SpinLock, OldIrql);
+
+	if (wasQueued)
+	{
+		Irp->IoStatus.Status = STATUS_CANCELLED;
+		Irp->IoStatus.Information = 0;
+		IoCompleteRequest(Irp, IO_NO_INCREMENT);
+	}
+	else
+	{
+		/* Hm, this shouldn't happen */
+		ASSERT(FALSE);
+	}
+}
+
+static NTSTATUS
+HandleReadIrp(
+	IN PDEVICE_OBJECT DeviceObject,
+	IN PIRP Irp,
+	BOOLEAN IsInStartIo)
 {
 	PCLASS_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
+	NTSTATUS Status;
+
+	DPRINT("HandleReadIrp(DeviceObject %p, Irp %p)\n", DeviceObject, Irp);
 
 	ASSERT(DeviceExtension->Common.IsClassDO);
 
 	if (DeviceExtension->InputCount > 0)
 	{
-		KIRQL oldIrql;
-		NTSTATUS Status;
 		SIZE_T NumberOfEntries;
 
 		NumberOfEntries = MIN(
 			DeviceExtension->InputCount,
 			IoGetCurrentIrpStackLocation(Irp)->Parameters.Read.Length / sizeof(KEYBOARD_INPUT_DATA));
 
-		KeAcquireSpinLock(&DeviceExtension->SpinLock, &oldIrql);
-
 		Status = FillEntries(
 			DeviceObject,
 			Irp,
@@ -790,22 +791,55 @@ ClassStartIo(
 			}
 
 			DeviceExtension->InputCount -= NumberOfEntries;
-			DeviceExtension->ReadIsPending = FALSE;
 
 			Irp->IoStatus.Information = NumberOfEntries * sizeof(KEYBOARD_INPUT_DATA);
 		}
 
 		/* Go to next packet and complete this request */
 		Irp->IoStatus.Status = Status;
-		KeReleaseSpinLock(&DeviceExtension->SpinLock, oldIrql);
 
+		if (IsInStartIo)
+			IoStartNextPacket(DeviceObject, TRUE);
+
+		(VOID)IoSetCancelRoutine(Irp, NULL);
 		IoCompleteRequest(Irp, IO_KEYBOARD_INCREMENT);
-		IoStartNextPacket(DeviceObject, FALSE);
+		DeviceExtension->PendingIrp = NULL;
 	}
 	else
 	{
-		DeviceExtension->ReadIsPending = TRUE;
+		(VOID)IoSetCancelRoutine(Irp, ClassCancelRoutine);
+		if (Irp->Cancel && IoSetCancelRoutine(Irp, NULL))
+		{
+			DeviceExtension->PendingIrp = NULL;
+			Status = STATUS_CANCELLED;
+		}
+		else
+		{
+			IoMarkIrpPending(Irp);
+			DeviceExtension->PendingIrp = Irp;
+			Status = STATUS_PENDING;
+			if (!IsInStartIo)
+				IoStartPacket(DeviceObject, Irp, NULL, NULL);
+		}
 	}
+	return Status;
+}
+
+static VOID NTAPI
+ClassStartIo(
+	IN PDEVICE_OBJECT DeviceObject,
+	IN PIRP Irp)
+{
+	PCLASS_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
+	KIRQL OldIrql;
+
+	DPRINT("ClassStartIo(DeviceObject %p, Irp %p)\n", DeviceObject, Irp);
+
+	ASSERT(DeviceExtension->Common.IsClassDO);
+
+	KeAcquireSpinLock(&DeviceExtension->SpinLock, &OldIrql);
+	HandleReadIrp(DeviceObject, Irp, TRUE);
+	KeReleaseSpinLock(&DeviceExtension->SpinLock, OldIrql);
 }
 
 static VOID NTAPI
diff --git a/reactos/drivers/input/kbdclass/kbdclass.h b/reactos/drivers/input/kbdclass/kbdclass.h
index 67ebb57f131..b62f24ea946 100644
--- a/reactos/drivers/input/kbdclass/kbdclass.h
+++ b/reactos/drivers/input/kbdclass/kbdclass.h
@@ -59,7 +59,7 @@ typedef struct _CLASS_DEVICE_EXTENSION
 	LIST_ENTRY ListHead;
 	KSPIN_LOCK ListSpinLock;
 	KSPIN_LOCK SpinLock;
-	BOOLEAN ReadIsPending;
+	PIRP PendingIrp;
 	SIZE_T InputCount;
 	PKEYBOARD_INPUT_DATA PortData;
 	LPCWSTR DeviceName;
diff --git a/reactos/drivers/input/mouclass/mouclass.c b/reactos/drivers/input/mouclass/mouclass.c
index 9e39b986b40..82003c33a0b 100644
--- a/reactos/drivers/input/mouclass/mouclass.c
+++ b/reactos/drivers/input/mouclass/mouclass.c
@@ -1,9 +1,9 @@
-/* 
+/*
  * COPYRIGHT:       See COPYING in the top level directory
  * PROJECT:         ReactOS Mouse class driver
  * FILE:            drivers/mouclass/mouclass.c
  * PURPOSE:         Mouse class driver
- * 
+ *
  * PROGRAMMERS:     Hervé Poussineau (hpoussin@reactos.org)
  */
 
@@ -19,6 +19,12 @@ static DRIVER_DISPATCH ClassDeviceControl;
 static DRIVER_DISPATCH IrpStub;
 static DRIVER_ADD_DEVICE ClassAddDevice;
 static DRIVER_STARTIO ClassStartIo;
+static DRIVER_CANCEL ClassCancelRoutine;
+static NTSTATUS
+HandleReadIrp(
+	IN PDEVICE_OBJECT DeviceObject,
+	IN PIRP Irp,
+	BOOLEAN IsInStartIo);
 
 static VOID NTAPI
 DriverUnload(IN PDRIVER_OBJECT DriverObject)
@@ -82,8 +88,14 @@ ClassRead(
 	IN PDEVICE_OBJECT DeviceObject,
 	IN PIRP Irp)
 {
+	PCLASS_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
+	KIRQL OldIrql;
+	NTSTATUS Status;
+
 	DPRINT("IRP_MJ_READ\n");
 
+	ASSERT(DeviceExtension->Common.IsClassDO);
+
 	if (!((PCOMMON_DEVICE_EXTENSION)DeviceObject->DeviceExtension)->IsClassDO)
 		return ForwardIrpAndForget(DeviceObject, Irp);
 
@@ -96,9 +108,10 @@ ClassRead(
 		return STATUS_BUFFER_TOO_SMALL;
 	}
 
-	IoMarkIrpPending(Irp);
-	IoStartPacket(DeviceObject, Irp, NULL, NULL);
-	return STATUS_PENDING;
+	KeAcquireSpinLock(&DeviceExtension->SpinLock, &OldIrql);
+	Status = HandleReadIrp(DeviceObject, Irp, FALSE);
+	KeReleaseSpinLock(&DeviceExtension->SpinLock, OldIrql);
+	return Status;
 }
 
 static NTSTATUS NTAPI
@@ -347,9 +360,8 @@ cleanup:
 	InitializeListHead(&DeviceExtension->ListHead);
 	KeInitializeSpinLock(&DeviceExtension->ListSpinLock);
 	KeInitializeSpinLock(&DeviceExtension->SpinLock);
-	DeviceExtension->ReadIsPending = FALSE;
 	DeviceExtension->InputCount = 0;
-	DeviceExtension->PortData = ExAllocatePoolWithTag(NonPagedPool, DeviceExtension->DriverExtension->DataQueueSize * sizeof(KEYBOARD_INPUT_DATA), CLASS_TAG);
+	DeviceExtension->PortData = ExAllocatePoolWithTag(NonPagedPool, DeviceExtension->DriverExtension->DataQueueSize * sizeof(MOUSE_INPUT_DATA), CLASS_TAG);
 	if (!DeviceExtension->PortData)
 	{
 		ExFreePoolWithTag(DeviceNameU.Buffer, CLASS_TAG);
@@ -430,56 +442,16 @@ ClassCallback(
 	IN OUT PULONG ConsumedCount)
 {
 	PCLASS_DEVICE_EXTENSION ClassDeviceExtension = ClassDeviceObject->DeviceExtension;
-	PIRP Irp = NULL;
 	KIRQL OldIrql;
 	SIZE_T InputCount = DataEnd - DataStart;
 	SIZE_T ReadSize;
 
+	DPRINT("ClassCallback()\n");
+
 	ASSERT(ClassDeviceExtension->Common.IsClassDO);
 
 	KeAcquireSpinLock(&ClassDeviceExtension->SpinLock, &OldIrql);
-
-	DPRINT("ClassCallback()\n");
-	/* A filter driver might have consumed all the data already; I'm
-	 * not sure if they are supposed to move the packets when they
-	 * consume them though.
-	 */
-	if (ClassDeviceExtension->ReadIsPending == TRUE && InputCount)
-	{
-		/* A read request is waiting for input, so go straight to it */
-		NTSTATUS Status;
-		SIZE_T NumberOfEntries;
-
-		Irp = ClassDeviceObject->CurrentIrp;
-		ClassDeviceObject->CurrentIrp = NULL;
-
-		NumberOfEntries = MIN(
-			InputCount,
-			IoGetCurrentIrpStackLocation(Irp)->Parameters.Read.Length / sizeof(MOUSE_INPUT_DATA));
-
-		Status = FillEntries(
-			ClassDeviceObject,
-			Irp,
-			DataStart,
-			NumberOfEntries);
-
-		if (NT_SUCCESS(Status))
-		{
-			/* Go to next packet and complete this request with STATUS_SUCCESS */
-			Irp->IoStatus.Status = STATUS_SUCCESS;
-			Irp->IoStatus.Information = NumberOfEntries * sizeof(MOUSE_INPUT_DATA);
-
-			ClassDeviceExtension->ReadIsPending = FALSE;
-
-			/* Skip the packet we just sent away */
-			DataStart += NumberOfEntries;
-			(*ConsumedCount) += (ULONG)NumberOfEntries;
-			InputCount -= NumberOfEntries;
-		}
-	}
-
-	/* If we have data from the port driver and a higher service to send the data to */
-	if (InputCount != 0)
+	if (InputCount > 0)
 	{
 		if (ClassDeviceExtension->InputCount + InputCount > ClassDeviceExtension->DriverExtension->DataQueueSize)
 		{
@@ -505,20 +477,13 @@ ClassCallback(
 		ClassDeviceExtension->InputCount += ReadSize;
 
 		(*ConsumedCount) += (ULONG)ReadSize;
-	}
-	else
-	{
-		DPRINT("ClassCallback(): no more data to process\n");
-	}
 
+		/* Complete pending IRP (if any) */
+		if (ClassDeviceExtension->PendingIrp)
+			HandleReadIrp(ClassDeviceObject, ClassDeviceExtension->PendingIrp, FALSE);
+	}
 	KeReleaseSpinLock(&ClassDeviceExtension->SpinLock, OldIrql);
 
-	if (Irp != NULL)
-	{
-		IoStartNextPacket(ClassDeviceObject, FALSE);
-		IoCompleteRequest(Irp, IO_MOUSE_INCREMENT);
-	}
-
 	DPRINT("Leaving ClassCallback()\n");
 	return TRUE;
 }
@@ -669,6 +634,7 @@ ClassAddDevice(
 		DPRINT("IoCreateDevice() failed with status 0x%08lx\n", Status);
 		goto cleanup;
 	}
+	IoSetStartIoAttributes(Fdo, TRUE, TRUE);
 
 	DeviceExtension = (PPORT_DEVICE_EXTENSION)Fdo->DeviceExtension;
 	RtlZeroMemory(DeviceExtension, sizeof(PORT_DEVICE_EXTENSION));
@@ -729,26 +695,61 @@ cleanup:
 }
 
 static VOID NTAPI
-ClassStartIo(
+ClassCancelRoutine(
 	IN PDEVICE_OBJECT DeviceObject,
 	IN PIRP Irp)
+{
+	PCLASS_DEVICE_EXTENSION ClassDeviceExtension = DeviceObject->DeviceExtension;
+	KIRQL OldIrql;
+	BOOLEAN wasQueued = FALSE;
+
+	DPRINT("ClassCancelRoutine(DeviceObject %p, Irp %p)\n", DeviceObject, Irp);
+
+	ASSERT(ClassDeviceExtension->Common.IsClassDO);
+
+	KeAcquireSpinLock(&ClassDeviceExtension->SpinLock, &OldIrql);
+	IoAcquireCancelSpinLock(&OldIrql);
+	if (ClassDeviceExtension->PendingIrp == Irp)
+	{
+		ClassDeviceExtension->PendingIrp = NULL;
+		wasQueued = TRUE;
+	}
+	KeReleaseSpinLock(&ClassDeviceExtension->SpinLock, OldIrql);
+
+	if (wasQueued)
+	{
+		Irp->IoStatus.Status = STATUS_CANCELLED;
+		Irp->IoStatus.Information = 0;
+		IoCompleteRequest(Irp, IO_NO_INCREMENT);
+	}
+	else
+	{
+		/* Hm, this shouldn't happen */
+		ASSERT(FALSE);
+	}
+}
+
+static NTSTATUS
+HandleReadIrp(
+	IN PDEVICE_OBJECT DeviceObject,
+	IN PIRP Irp,
+	BOOLEAN IsInStartIo)
 {
 	PCLASS_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
+	NTSTATUS Status;
+
+	DPRINT("HandleReadIrp(DeviceObject %p, Irp %p)\n", DeviceObject, Irp);
 
 	ASSERT(DeviceExtension->Common.IsClassDO);
 
 	if (DeviceExtension->InputCount > 0)
 	{
-		KIRQL oldIrql;
-		NTSTATUS Status;
 		SIZE_T NumberOfEntries;
 
 		NumberOfEntries = MIN(
 			DeviceExtension->InputCount,
 			IoGetCurrentIrpStackLocation(Irp)->Parameters.Read.Length / sizeof(MOUSE_INPUT_DATA));
 
-		KeAcquireSpinLock(&DeviceExtension->SpinLock, &oldIrql);
-
 		Status = FillEntries(
 			DeviceObject,
 			Irp,
@@ -766,22 +767,55 @@ ClassStartIo(
 			}
 
 			DeviceExtension->InputCount -= NumberOfEntries;
-			DeviceExtension->ReadIsPending = FALSE;
 
 			Irp->IoStatus.Information = NumberOfEntries * sizeof(MOUSE_INPUT_DATA);
 		}
 
 		/* Go to next packet and complete this request */
 		Irp->IoStatus.Status = Status;
-		KeReleaseSpinLock(&DeviceExtension->SpinLock, oldIrql);
 
+		if (IsInStartIo)
+			IoStartNextPacket(DeviceObject, TRUE);
+
+		(VOID)IoSetCancelRoutine(Irp, NULL);
 		IoCompleteRequest(Irp, IO_MOUSE_INCREMENT);
-		IoStartNextPacket(DeviceObject, FALSE);
+		DeviceExtension->PendingIrp = NULL;
 	}
 	else
 	{
-		DeviceExtension->ReadIsPending = TRUE;
+		(VOID)IoSetCancelRoutine(Irp, ClassCancelRoutine);
+		if (Irp->Cancel && IoSetCancelRoutine(Irp, NULL))
+		{
+			DeviceExtension->PendingIrp = NULL;
+			Status = STATUS_CANCELLED;
+		}
+		else
+		{
+			IoMarkIrpPending(Irp);
+			DeviceExtension->PendingIrp = Irp;
+			Status = STATUS_PENDING;
+			if (!IsInStartIo)
+				IoStartPacket(DeviceObject, Irp, NULL, NULL);
+		}
 	}
+	return Status;
+}
+
+static VOID NTAPI
+ClassStartIo(
+	IN PDEVICE_OBJECT DeviceObject,
+	IN PIRP Irp)
+{
+	PCLASS_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
+	KIRQL OldIrql;
+
+	DPRINT("ClassStartIo(DeviceObject %p, Irp %p)\n", DeviceObject, Irp);
+
+	ASSERT(DeviceExtension->Common.IsClassDO);
+
+	KeAcquireSpinLock(&DeviceExtension->SpinLock, &OldIrql);
+	HandleReadIrp(DeviceObject, Irp, TRUE);
+	KeReleaseSpinLock(&DeviceExtension->SpinLock, OldIrql);
 }
 
 static VOID NTAPI
diff --git a/reactos/drivers/input/mouclass/mouclass.h b/reactos/drivers/input/mouclass/mouclass.h
index 3723c6bd6ec..feba1b05c4b 100644
--- a/reactos/drivers/input/mouclass/mouclass.h
+++ b/reactos/drivers/input/mouclass/mouclass.h
@@ -59,7 +59,7 @@ typedef struct _CLASS_DEVICE_EXTENSION
 	LIST_ENTRY ListHead;
 	KSPIN_LOCK ListSpinLock;
 	KSPIN_LOCK SpinLock;
-	BOOLEAN ReadIsPending;
+	PIRP PendingIrp;
 	SIZE_T InputCount;
 	PMOUSE_INPUT_DATA PortData;
 	LPCWSTR DeviceName;