mouclass.c

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/*
 * 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)
 */

#define INITGUID
#include "mouclass.h"

static DRIVER_UNLOAD DriverUnload;
static DRIVER_DISPATCH ClassCreate;
static DRIVER_DISPATCH ClassClose;
static DRIVER_DISPATCH ClassCleanup;
static DRIVER_DISPATCH ClassRead;
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)
{
    // nothing to do here yet
}

static NTSTATUS NTAPI
ClassCreate(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp)
{
    TRACE_(CLASS_NAME, "IRP_MJ_CREATE\n");

    if (!((PCOMMON_DEVICE_EXTENSION)DeviceObject->DeviceExtension)->IsClassDO)
        return ForwardIrpAndForget(DeviceObject, Irp);

    /* FIXME: open all associated Port devices */
    Irp->IoStatus.Status = STATUS_SUCCESS;
    Irp->IoStatus.Information = 0;
    IoCompleteRequest(Irp, IO_NO_INCREMENT);
    return STATUS_SUCCESS;
}

static NTSTATUS NTAPI
ClassClose(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp)
{
    TRACE_(CLASS_NAME, "IRP_MJ_CLOSE\n");

    if (!((PCOMMON_DEVICE_EXTENSION)DeviceObject->DeviceExtension)->IsClassDO)
        return ForwardIrpAndForget(DeviceObject, Irp);

    /* FIXME: close all associated Port devices */
    Irp->IoStatus.Status = STATUS_SUCCESS;
    Irp->IoStatus.Information = 0;
    IoCompleteRequest(Irp, IO_NO_INCREMENT);
    return STATUS_SUCCESS;
}

static NTSTATUS NTAPI
ClassCleanup(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp)
{
    TRACE_(CLASS_NAME, "IRP_MJ_CLEANUP\n");

    if (!((PCOMMON_DEVICE_EXTENSION)DeviceObject->DeviceExtension)->IsClassDO)
        return ForwardIrpAndForget(DeviceObject, Irp);

    /* FIXME: cleanup all associated Port devices */
    Irp->IoStatus.Status = STATUS_SUCCESS;
    Irp->IoStatus.Information = 0;
    IoCompleteRequest(Irp, IO_NO_INCREMENT);
    return STATUS_SUCCESS;
}

static NTSTATUS NTAPI
ClassRead(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp)
{
    PCLASS_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
    KIRQL OldIrql;
    NTSTATUS Status;

    TRACE_(CLASS_NAME, "IRP_MJ_READ\n");

    ASSERT(DeviceExtension->Common.IsClassDO);

    if (!((PCOMMON_DEVICE_EXTENSION)DeviceObject->DeviceExtension)->IsClassDO)
        return ForwardIrpAndForget(DeviceObject, Irp);

    if (IoGetCurrentIrpStackLocation(Irp)->Parameters.Read.Length < sizeof(MOUSE_INPUT_DATA))
    {
        Irp->IoStatus.Status = STATUS_BUFFER_TOO_SMALL;
        Irp->IoStatus.Information = 0;
        IoCompleteRequest(Irp, IO_NO_INCREMENT);

        return STATUS_BUFFER_TOO_SMALL;
    }

    KeAcquireSpinLock(&DeviceExtension->SpinLock, &OldIrql);
    Status = HandleReadIrp(DeviceObject, Irp, FALSE);
    KeReleaseSpinLock(&DeviceExtension->SpinLock, OldIrql);
    return Status;
}

static NTSTATUS NTAPI
ClassDeviceControl(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp)
{
    //PCLASS_DEVICE_EXTENSION DeviceExtension;
    NTSTATUS Status = STATUS_NOT_SUPPORTED;

    TRACE_(CLASS_NAME, "IRP_MJ_DEVICE_CONTROL\n");

    if (!((PCOMMON_DEVICE_EXTENSION)DeviceObject->DeviceExtension)->IsClassDO)
        return ForwardIrpAndForget(DeviceObject, Irp);

    //DeviceExtension = (PCLASS_DEVICE_EXTENSION)DeviceObject->DeviceExtension;

    switch (IoGetCurrentIrpStackLocation(Irp)->Parameters.DeviceIoControl.IoControlCode)
    {
        case IOCTL_MOUSE_QUERY_ATTRIBUTES:
        {
            /* FIXME: We hope that all devices will return the same result.
             * Ask only the first one */
            PLIST_ENTRY Head = &((PCLASS_DEVICE_EXTENSION)DeviceObject->DeviceExtension)->ListHead;
            if (Head->Flink != Head)
            {
                /* We have at least one device */
                PPORT_DEVICE_EXTENSION DevExt = CONTAINING_RECORD(Head->Flink, PORT_DEVICE_EXTENSION, ListEntry);
                IoGetCurrentIrpStackLocation(Irp)->MajorFunction = IRP_MJ_INTERNAL_DEVICE_CONTROL;
                IoSkipCurrentIrpStackLocation(Irp);
                return IoCallDriver(DevExt->DeviceObject, Irp);
            }
            break;
        }
        default:
            WARN_(CLASS_NAME, "IRP_MJ_DEVICE_CONTROL / unknown I/O control code 0x%lx\n",
                IoGetCurrentIrpStackLocation(Irp)->Parameters.DeviceIoControl.IoControlCode);
            ASSERT(FALSE);
            break;
    }

    Irp->IoStatus.Status = Status;
    Irp->IoStatus.Information = 0;
    IoCompleteRequest(Irp, IO_NO_INCREMENT);

    return Status;
}

static NTSTATUS NTAPI
IrpStub(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp)
{
    NTSTATUS Status = STATUS_NOT_SUPPORTED;

    if (!((PCOMMON_DEVICE_EXTENSION)DeviceObject->DeviceExtension)->IsClassDO)
    {
        /* Forward some IRPs to lower device */
        switch (IoGetCurrentIrpStackLocation(Irp)->MajorFunction)
        {
            case IRP_MJ_PNP:
            case IRP_MJ_INTERNAL_DEVICE_CONTROL:
                return ForwardIrpAndForget(DeviceObject, Irp);
            default:
            {
                ERR_(CLASS_NAME, "Port DO stub for major function 0x%lx\n",
                    IoGetCurrentIrpStackLocation(Irp)->MajorFunction);
                ASSERT(FALSE);
            }
        }
    }
    else
    {
        ERR_(CLASS_NAME, "Class DO stub for major function 0x%lx\n",
            IoGetCurrentIrpStackLocation(Irp)->MajorFunction);
        ASSERT(FALSE);
    }

    Irp->IoStatus.Status = Status;
    IoCompleteRequest(Irp, IO_NO_INCREMENT);
    return Status;
}

static NTSTATUS
ReadRegistryEntries(
    IN PUNICODE_STRING RegistryPath,
    IN PCLASS_DRIVER_EXTENSION DriverExtension)
{
    UNICODE_STRING ParametersRegistryKey;
    RTL_QUERY_REGISTRY_TABLE Parameters[4];
    NTSTATUS Status;

    ULONG DefaultConnectMultiplePorts = 1;
    ULONG DefaultDataQueueSize = 0x64;
    PCWSTR DefaultDeviceBaseName = L"PointerClass";

    ParametersRegistryKey.Length = 0;
    ParametersRegistryKey.MaximumLength = RegistryPath->Length + sizeof(L"\\Parameters") + sizeof(UNICODE_NULL);
    ParametersRegistryKey.Buffer = ExAllocatePoolWithTag(PagedPool, ParametersRegistryKey.MaximumLength, CLASS_TAG);
    if (!ParametersRegistryKey.Buffer)
    {
        WARN_(CLASS_NAME, "ExAllocatePoolWithTag() failed\n");
        return STATUS_NO_MEMORY;
    }
    RtlCopyUnicodeString(&ParametersRegistryKey, RegistryPath);
    RtlAppendUnicodeToString(&ParametersRegistryKey, L"\\Parameters");
    ParametersRegistryKey.Buffer[ParametersRegistryKey.Length / sizeof(WCHAR)] = UNICODE_NULL;

    RtlZeroMemory(Parameters, sizeof(Parameters));

    Parameters[0].Flags = RTL_QUERY_REGISTRY_DIRECT | RTL_REGISTRY_OPTIONAL;
    Parameters[0].Name = L"ConnectMultiplePorts";
    Parameters[0].EntryContext = &DriverExtension->ConnectMultiplePorts;
    Parameters[0].DefaultType = REG_DWORD;
    Parameters[0].DefaultData = &DefaultConnectMultiplePorts;
    Parameters[0].DefaultLength = sizeof(ULONG);

    Parameters[1].Flags = RTL_QUERY_REGISTRY_DIRECT | RTL_REGISTRY_OPTIONAL;
    Parameters[1].Name = L"MouseDataQueueSize";
    Parameters[1].EntryContext = &DriverExtension->DataQueueSize;
    Parameters[1].DefaultType = REG_DWORD;
    Parameters[1].DefaultData = &DefaultDataQueueSize;
    Parameters[1].DefaultLength = sizeof(ULONG);

    Parameters[2].Flags = RTL_QUERY_REGISTRY_DIRECT | RTL_REGISTRY_OPTIONAL;
    Parameters[2].Name = L"PointerDeviceBaseName";
    Parameters[2].EntryContext = &DriverExtension->DeviceBaseName;
    Parameters[2].DefaultType = REG_SZ;
    Parameters[2].DefaultData = (PVOID)DefaultDeviceBaseName;
    Parameters[2].DefaultLength = 0;

    Status = RtlQueryRegistryValues(
        RTL_REGISTRY_ABSOLUTE,
        ParametersRegistryKey.Buffer,
        Parameters,
        NULL,
        NULL);

    if (NT_SUCCESS(Status))
    {
        /* Check values */
        if (DriverExtension->ConnectMultiplePorts != 0
            && DriverExtension->ConnectMultiplePorts != 1)
        {
            DriverExtension->ConnectMultiplePorts = DefaultConnectMultiplePorts;
        }
        if (DriverExtension->DataQueueSize == 0)
        {
            DriverExtension->DataQueueSize = DefaultDataQueueSize;
        }
    }
    else if (Status == STATUS_OBJECT_NAME_NOT_FOUND)
    {
        /* Registry path doesn't exist. Set defaults */
        DriverExtension->ConnectMultiplePorts = DefaultConnectMultiplePorts;
        DriverExtension->DataQueueSize = DefaultDataQueueSize;
        if (RtlCreateUnicodeString(&DriverExtension->DeviceBaseName, DefaultDeviceBaseName))
            Status = STATUS_SUCCESS;
        else
            Status = STATUS_NO_MEMORY;
    }

    ExFreePoolWithTag(ParametersRegistryKey.Buffer, CLASS_TAG);
    return Status;
}

static NTSTATUS
CreateClassDeviceObject(
    IN PDRIVER_OBJECT DriverObject,
    OUT PDEVICE_OBJECT *ClassDO OPTIONAL)
{
    PCLASS_DRIVER_EXTENSION DriverExtension;
    ULONG DeviceId = 0;
    ULONG PrefixLength;
    UNICODE_STRING DeviceNameU;
    PWSTR DeviceIdW = NULL; /* Pointer into DeviceNameU.Buffer */
    PDEVICE_OBJECT Fdo;
    PCLASS_DEVICE_EXTENSION DeviceExtension;
    NTSTATUS Status;

    TRACE_(CLASS_NAME, "CreateClassDeviceObject(0x%p)\n", DriverObject);

    /* Create new device object */
    DriverExtension = IoGetDriverObjectExtension(DriverObject, DriverObject);
    DeviceNameU.Length = 0;
    DeviceNameU.MaximumLength =
        wcslen(L"\\Device\\") * sizeof(WCHAR)    /* "\Device\" */
        + DriverExtension->DeviceBaseName.Length /* "PointerClass" */
        + 4 * sizeof(WCHAR)                      /* Id between 0 and 9999 */
        + sizeof(UNICODE_NULL);                  /* Final NULL char */
    DeviceNameU.Buffer = ExAllocatePoolWithTag(PagedPool, DeviceNameU.MaximumLength, CLASS_TAG);
    if (!DeviceNameU.Buffer)
    {
        WARN_(CLASS_NAME, "ExAllocatePoolWithTag() failed\n");
        return STATUS_NO_MEMORY;
    }
    Status = RtlAppendUnicodeToString(&DeviceNameU, L"\\Device\\");
    if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "RtlAppendUnicodeToString() failed with status 0x%08lx\n", Status);
        goto cleanup;
    }
    Status = RtlAppendUnicodeStringToString(&DeviceNameU, &DriverExtension->DeviceBaseName);
    if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "RtlAppendUnicodeStringToString() failed with status 0x%08lx\n", Status);
        goto cleanup;
    }
    PrefixLength = DeviceNameU.MaximumLength - 4 * sizeof(WCHAR) - sizeof(UNICODE_NULL);
    DeviceIdW = &DeviceNameU.Buffer[PrefixLength / sizeof(WCHAR)];
    while (DeviceId < 9999)
    {
        DeviceNameU.Length = (USHORT)(PrefixLength + swprintf(DeviceIdW, L"%lu", DeviceId) * sizeof(WCHAR));
        Status = IoCreateDevice(
            DriverObject,
            sizeof(CLASS_DEVICE_EXTENSION),
            &DeviceNameU,
            FILE_DEVICE_MOUSE,
            FILE_DEVICE_SECURE_OPEN,
            FALSE,
            &Fdo);
        if (NT_SUCCESS(Status))
            goto cleanup;
        else if (Status != STATUS_OBJECT_NAME_COLLISION)
        {
            WARN_(CLASS_NAME, "IoCreateDevice() failed with status 0x%08lx\n", Status);
            goto cleanup;
        }
        DeviceId++;
    }
    WARN_(CLASS_NAME, "Too many devices starting with '\\Device\\%wZ'\n", &DriverExtension->DeviceBaseName);
    Status = STATUS_TOO_MANY_NAMES;
cleanup:
    if (!NT_SUCCESS(Status))
    {
        ExFreePoolWithTag(DeviceNameU.Buffer, CLASS_TAG);
        return Status;
    }

    DeviceExtension = (PCLASS_DEVICE_EXTENSION)Fdo->DeviceExtension;
    RtlZeroMemory(DeviceExtension, sizeof(CLASS_DEVICE_EXTENSION));
    DeviceExtension->Common.IsClassDO = TRUE;
    DeviceExtension->DriverExtension = DriverExtension;
    InitializeListHead(&DeviceExtension->ListHead);
    KeInitializeSpinLock(&DeviceExtension->ListSpinLock);
    KeInitializeSpinLock(&DeviceExtension->SpinLock);
    DeviceExtension->InputCount = 0;
    DeviceExtension->PortData = ExAllocatePoolWithTag(NonPagedPool, DeviceExtension->DriverExtension->DataQueueSize * sizeof(MOUSE_INPUT_DATA), CLASS_TAG);
    if (!DeviceExtension->PortData)
    {
        ExFreePoolWithTag(DeviceNameU.Buffer, CLASS_TAG);
        return STATUS_NO_MEMORY;
    }
    DeviceExtension->DeviceName = DeviceNameU.Buffer;
    Fdo->Flags |= DO_POWER_PAGABLE;
    Fdo->Flags &= ~DO_DEVICE_INITIALIZING;
    Fdo->Flags |= DO_BUFFERED_IO;

    /* Add entry entry to HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\[DeviceBaseName] */
    RtlWriteRegistryValue(
        RTL_REGISTRY_DEVICEMAP,
        DriverExtension->DeviceBaseName.Buffer,
        DeviceExtension->DeviceName,
        REG_SZ,
        DriverExtension->RegistryPath.Buffer,
        DriverExtension->RegistryPath.MaximumLength);

    if (ClassDO)
        *ClassDO = Fdo;

    return STATUS_SUCCESS;
}

static NTSTATUS
FillEntries(
    IN PDEVICE_OBJECT ClassDeviceObject,
    IN PIRP Irp,
    IN PMOUSE_INPUT_DATA DataStart,
    IN SIZE_T NumberOfEntries)
{
    NTSTATUS Status = STATUS_SUCCESS;

    if (ClassDeviceObject->Flags & DO_BUFFERED_IO)
    {
        RtlCopyMemory(
            Irp->AssociatedIrp.SystemBuffer,
            DataStart,
            NumberOfEntries * sizeof(MOUSE_INPUT_DATA));
    }
    else if (ClassDeviceObject->Flags & DO_DIRECT_IO)
    {
        PVOID DestAddress = MmGetSystemAddressForMdlSafe(Irp->MdlAddress, NormalPagePriority);
        if (DestAddress)
        {
            RtlCopyMemory(
                DestAddress,
                DataStart,
                NumberOfEntries * sizeof(MOUSE_INPUT_DATA));
        }
        else
            Status = STATUS_UNSUCCESSFUL;
    }
    else
    {
        _SEH2_TRY
        {
            RtlCopyMemory(
                Irp->UserBuffer,
                DataStart,
                NumberOfEntries * sizeof(MOUSE_INPUT_DATA));
        }
        _SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
        {
            Status = _SEH2_GetExceptionCode();
        }
        _SEH2_END;
    }

    return Status;
}

static BOOLEAN NTAPI
ClassCallback(
    IN PDEVICE_OBJECT ClassDeviceObject,
    IN OUT PMOUSE_INPUT_DATA DataStart,
    IN PMOUSE_INPUT_DATA DataEnd,
    IN OUT PULONG ConsumedCount)
{
    PCLASS_DEVICE_EXTENSION ClassDeviceExtension = ClassDeviceObject->DeviceExtension;
    KIRQL OldIrql;
    SIZE_T InputCount = DataEnd - DataStart;
    SIZE_T ReadSize;

    TRACE_(CLASS_NAME, "ClassCallback()\n");

    ASSERT(ClassDeviceExtension->Common.IsClassDO);

    KeAcquireSpinLock(&ClassDeviceExtension->SpinLock, &OldIrql);
    if (InputCount > 0)
    {
        if (ClassDeviceExtension->InputCount + InputCount > ClassDeviceExtension->DriverExtension->DataQueueSize)
        {
            /*
             * We're exceeding the buffer, and data will be thrown away...
             * FIXME: What could we do, as we are at DISPATCH_LEVEL?
             */
            ReadSize = ClassDeviceExtension->DriverExtension->DataQueueSize - ClassDeviceExtension->InputCount;
        }
        else
            ReadSize = InputCount;

        /*
         * Move the input data from the port data queue to our class data
         * queue.
         */
        RtlCopyMemory(
            &ClassDeviceExtension->PortData[ClassDeviceExtension->InputCount],
            (PCHAR)DataStart,
            sizeof(MOUSE_INPUT_DATA) * ReadSize);

        /* Move the counter up */
        ClassDeviceExtension->InputCount += ReadSize;

        (*ConsumedCount) += (ULONG)ReadSize;

        /* Complete pending IRP (if any) */
        if (ClassDeviceExtension->PendingIrp)
            HandleReadIrp(ClassDeviceObject, ClassDeviceExtension->PendingIrp, FALSE);
    }
    KeReleaseSpinLock(&ClassDeviceExtension->SpinLock, OldIrql);

    TRACE_(CLASS_NAME, "Leaving ClassCallback()\n");
    return TRUE;
}

/* Send IOCTL_INTERNAL_*_CONNECT to port */
static NTSTATUS
ConnectPortDriver(
    IN PDEVICE_OBJECT PortDO,
    IN PDEVICE_OBJECT ClassDO)
{
    KEVENT Event;
    PIRP Irp;
    IO_STATUS_BLOCK IoStatus;
    CONNECT_DATA ConnectData;
    NTSTATUS Status;

    TRACE_(CLASS_NAME, "Connecting PortDO %p to ClassDO %p\n", PortDO, ClassDO);

    KeInitializeEvent(&Event, NotificationEvent, FALSE);

    ConnectData.ClassDeviceObject = ClassDO;
    ConnectData.ClassService      = ClassCallback;

    Irp = IoBuildDeviceIoControlRequest(
        IOCTL_INTERNAL_MOUSE_CONNECT,
        PortDO,
        &ConnectData, sizeof(CONNECT_DATA),
        NULL, 0,
        TRUE, &Event, &IoStatus);
    if (!Irp)
        return STATUS_INSUFFICIENT_RESOURCES;

    Status = IoCallDriver(PortDO, Irp);

    if (Status == STATUS_PENDING)
        KeWaitForSingleObject(&Event, Suspended, KernelMode, FALSE, NULL);
    else
        IoStatus.Status = Status;

    if (NT_SUCCESS(IoStatus.Status))
    {
        ObReferenceObject(PortDO);
        ExInterlockedInsertTailList(
            &((PCLASS_DEVICE_EXTENSION)ClassDO->DeviceExtension)->ListHead,
            &((PPORT_DEVICE_EXTENSION)PortDO->DeviceExtension)->ListEntry,
            &((PCLASS_DEVICE_EXTENSION)ClassDO->DeviceExtension)->ListSpinLock);
        if (ClassDO->StackSize <= PortDO->StackSize)
        {
            /* Increase the stack size, in case we have to
             * forward some IRPs to the port device object
             */
            ClassDO->StackSize = PortDO->StackSize + 1;
        }
    }

    return IoStatus.Status;
}

/* Send IOCTL_INTERNAL_*_DISCONNECT to port + destroy the Port DO */
static VOID
DestroyPortDriver(
    IN PDEVICE_OBJECT PortDO)
{
    PPORT_DEVICE_EXTENSION DeviceExtension;
    PCLASS_DEVICE_EXTENSION ClassDeviceExtension;
    PCLASS_DRIVER_EXTENSION DriverExtension;
    KEVENT Event;
    PIRP Irp;
    IO_STATUS_BLOCK IoStatus;
    KIRQL OldIrql;
    NTSTATUS Status;

    TRACE_(CLASS_NAME, "Destroying PortDO %p\n", PortDO);

    DeviceExtension = (PPORT_DEVICE_EXTENSION)PortDO->DeviceExtension;
    ClassDeviceExtension = DeviceExtension->ClassDO->DeviceExtension;
    DriverExtension = IoGetDriverObjectExtension(PortDO->DriverObject, PortDO->DriverObject);

    /* Send IOCTL_INTERNAL_*_DISCONNECT */
    KeInitializeEvent(&Event, NotificationEvent, FALSE);
    Irp = IoBuildDeviceIoControlRequest(
        IOCTL_INTERNAL_MOUSE_DISCONNECT,
        PortDO,
        NULL, 0,
        NULL, 0,
        TRUE, &Event, &IoStatus);
    if (Irp)
    {
        Status = IoCallDriver(PortDO, Irp);
        if (Status == STATUS_PENDING)
            KeWaitForSingleObject(&Event, Suspended, KernelMode, FALSE, NULL);
    }

    /* Remove from ClassDeviceExtension->ListHead list */
    KeAcquireSpinLock(&ClassDeviceExtension->ListSpinLock, &OldIrql);
    RemoveHeadList(DeviceExtension->ListEntry.Blink);
    KeReleaseSpinLock(&ClassDeviceExtension->ListSpinLock, OldIrql);

    /* Remove entry from HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP\[DeviceBaseName] */
    RtlDeleteRegistryValue(
        RTL_REGISTRY_DEVICEMAP,
        DriverExtension->DeviceBaseName.Buffer,
        ClassDeviceExtension->DeviceName);

    if (DeviceExtension->LowerDevice)
        IoDetachDevice(DeviceExtension->LowerDevice);
    ObDereferenceObject(PortDO);

    if (!DriverExtension->ConnectMultiplePorts && DeviceExtension->ClassDO)
    {
        ExFreePoolWithTag(ClassDeviceExtension->PortData, CLASS_TAG);
        ExFreePoolWithTag((PVOID)ClassDeviceExtension->DeviceName, CLASS_TAG);
        IoDeleteDevice(DeviceExtension->ClassDO);
    }

    IoDeleteDevice(PortDO);
}

static NTSTATUS NTAPI
ClassAddDevice(
    IN PDRIVER_OBJECT DriverObject,
    IN PDEVICE_OBJECT Pdo)
{
    PCLASS_DRIVER_EXTENSION DriverExtension;
    PDEVICE_OBJECT Fdo = NULL;
    PPORT_DEVICE_EXTENSION DeviceExtension = NULL;
    NTSTATUS Status;

    TRACE_(CLASS_NAME, "ClassAddDevice called. Pdo = 0x%p\n", Pdo);

    DriverExtension = IoGetDriverObjectExtension(DriverObject, DriverObject);

    if (Pdo == NULL)
        /* We may get a NULL Pdo at the first call as we're a legacy driver. Ignore it */
        return STATUS_SUCCESS;

    /* Create new device object */
    Status = IoCreateDevice(
        DriverObject,
        sizeof(PORT_DEVICE_EXTENSION),
        NULL,
        Pdo->DeviceType,
        Pdo->Characteristics & FILE_DEVICE_SECURE_OPEN ? FILE_DEVICE_SECURE_OPEN : 0,
        FALSE,
        &Fdo);
    if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "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));
    DeviceExtension->Common.IsClassDO = FALSE;
    DeviceExtension->DeviceObject = Fdo;
    DeviceExtension->PnpState = dsStopped;
    Status = IoAttachDeviceToDeviceStackSafe(Fdo, Pdo, &DeviceExtension->LowerDevice);
    if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "IoAttachDeviceToDeviceStackSafe() failed with status 0x%08lx\n", Status);
        goto cleanup;
    }
    if (DeviceExtension->LowerDevice->Flags & DO_POWER_PAGABLE)
        Fdo->Flags |= DO_POWER_PAGABLE;
    if (DeviceExtension->LowerDevice->Flags & DO_BUFFERED_IO)
        Fdo->Flags |= DO_BUFFERED_IO;
    if (DeviceExtension->LowerDevice->Flags & DO_DIRECT_IO)
        Fdo->Flags |= DO_DIRECT_IO;

    if (DriverExtension->ConnectMultiplePorts)
        DeviceExtension->ClassDO = DriverExtension->MainClassDeviceObject;
    else
    {
        /* We need a new class device object for this Fdo */
        Status = CreateClassDeviceObject(
            DriverObject,
            &DeviceExtension->ClassDO);
        if (!NT_SUCCESS(Status))
        {
            WARN_(CLASS_NAME, "CreateClassDeviceObject() failed with status 0x%08lx\n", Status);
            goto cleanup;
        }
    }
    Status = ConnectPortDriver(Fdo, DeviceExtension->ClassDO);
    if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "ConnectPortDriver() failed with status 0x%08lx\n", Status);
        goto cleanup;
    }
    Fdo->Flags &= ~DO_DEVICE_INITIALIZING;

    /* Register interface ; ignore the error (if any) as having
     * a registred interface is not so important... */
    Status = IoRegisterDeviceInterface(
        Pdo,
        &GUID_DEVINTERFACE_MOUSE,
        NULL,
        &DeviceExtension->InterfaceName);
    if (!NT_SUCCESS(Status))
        DeviceExtension->InterfaceName.Length = 0;

    return STATUS_SUCCESS;

cleanup:
    if (Fdo)
        DestroyPortDriver(Fdo);
    return Status;
}

static VOID NTAPI
ClassCancelRoutine(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp)
{
    PCLASS_DEVICE_EXTENSION ClassDeviceExtension = DeviceObject->DeviceExtension;
    KIRQL OldIrql;
    BOOLEAN wasQueued = FALSE;

    TRACE_(CLASS_NAME, "ClassCancelRoutine(DeviceObject %p, Irp %p)\n", DeviceObject, Irp);

    ASSERT(ClassDeviceExtension->Common.IsClassDO);

    IoReleaseCancelSpinLock(Irp->CancelIrql);

    KeAcquireSpinLock(&ClassDeviceExtension->SpinLock, &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
    {
        DPRINT1("Cancelled IRP is not pending. Race condition?\n");
    }
}

static NTSTATUS
HandleReadIrp(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp,
    BOOLEAN IsInStartIo)
{
    PCLASS_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
    NTSTATUS Status;
    KIRQL OldIrql;

    TRACE_(CLASS_NAME, "HandleReadIrp(DeviceObject %p, Irp %p)\n", DeviceObject, Irp);

    ASSERT(DeviceExtension->Common.IsClassDO);

    if (DeviceExtension->InputCount > 0)
    {
        SIZE_T NumberOfEntries;

        NumberOfEntries = MIN(
            DeviceExtension->InputCount,
            IoGetCurrentIrpStackLocation(Irp)->Parameters.Read.Length / sizeof(MOUSE_INPUT_DATA));

        Status = FillEntries(
            DeviceObject,
            Irp,
            DeviceExtension->PortData,
            NumberOfEntries);

        if (NT_SUCCESS(Status))
        {
            if (DeviceExtension->InputCount > NumberOfEntries)
            {
                RtlMoveMemory(
                    &DeviceExtension->PortData[0],
                    &DeviceExtension->PortData[NumberOfEntries],
                    (DeviceExtension->InputCount - NumberOfEntries) * sizeof(MOUSE_INPUT_DATA));
            }

            DeviceExtension->InputCount -= NumberOfEntries;

            Irp->IoStatus.Information = NumberOfEntries * sizeof(MOUSE_INPUT_DATA);
        }

        /* Go to next packet and complete this request */
        Irp->IoStatus.Status = Status;

        (VOID)IoSetCancelRoutine(Irp, NULL);
        IoCompleteRequest(Irp, IO_MOUSE_INCREMENT);
        DeviceExtension->PendingIrp = NULL;
    }
    else
    {
        IoAcquireCancelSpinLock(&OldIrql);
        if (Irp->Cancel)
        {
            DeviceExtension->PendingIrp = NULL;
            Status = STATUS_CANCELLED;
        }
        else
        {
            IoMarkIrpPending(Irp);
            DeviceExtension->PendingIrp = Irp;
            (VOID)IoSetCancelRoutine(Irp, ClassCancelRoutine);
            Status = STATUS_PENDING;
        }
        IoReleaseCancelSpinLock(OldIrql);
    }
    return Status;
}

static NTSTATUS NTAPI
ClassPnp(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp)
{
    PPORT_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
    PIO_STACK_LOCATION IrpSp = IoGetCurrentIrpStackLocation(Irp);
    OBJECT_ATTRIBUTES ObjectAttributes;
    IO_STATUS_BLOCK Iosb;
    NTSTATUS Status;
    
    switch (IrpSp->MinorFunction)
    {
        case IRP_MN_START_DEVICE:
            Status = ForwardIrpAndWait(DeviceObject, Irp);
            if (NT_SUCCESS(Status))
            {
                InitializeObjectAttributes(&ObjectAttributes,
                                           &DeviceExtension->InterfaceName,
                                           OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
                                           NULL,
                                           NULL);

                Status = ZwOpenFile(&DeviceExtension->FileHandle,
                                    FILE_READ_DATA,
                                    &ObjectAttributes,
                                    &Iosb,
                                    0,
                                    0);
                if (!NT_SUCCESS(Status))
                    DeviceExtension->FileHandle = NULL;
            }
            else
                DeviceExtension->FileHandle = NULL;
            Irp->IoStatus.Status = Status;
            IoCompleteRequest(Irp, IO_NO_INCREMENT);
            return Status;
            
        case IRP_MN_REMOVE_DEVICE:
        case IRP_MN_STOP_DEVICE:
            if (DeviceExtension->FileHandle)
            {
                ZwClose(DeviceExtension->FileHandle);
                DeviceExtension->FileHandle = NULL;
            }
            Status = STATUS_SUCCESS;
            break;

        default:
            Status = Irp->IoStatus.Status;
            break;
    }

    Irp->IoStatus.Status = Status;
    if (NT_SUCCESS(Status) || Status == STATUS_NOT_SUPPORTED)
    {
        IoSkipCurrentIrpStackLocation(Irp);
        return IoCallDriver(DeviceExtension->LowerDevice, Irp);
    }
    else
    {
        IoCompleteRequest(Irp, IO_NO_INCREMENT);
        return Status;
    }
}

static VOID NTAPI
ClassStartIo(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp)
{
    PCLASS_DEVICE_EXTENSION DeviceExtension = DeviceObject->DeviceExtension;
    KIRQL OldIrql;

    TRACE_(CLASS_NAME, "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
SearchForLegacyDrivers(
    IN PDRIVER_OBJECT DriverObject,
    IN PVOID Context, /* PCLASS_DRIVER_EXTENSION */
    IN ULONG Count)
{
    UNICODE_STRING DeviceMapKeyU = RTL_CONSTANT_STRING(L"\\REGISTRY\\MACHINE\\HARDWARE\\DEVICEMAP");
    PCLASS_DRIVER_EXTENSION DriverExtension;
    UNICODE_STRING PortBaseName = { 0, 0, NULL };
    PKEY_VALUE_BASIC_INFORMATION KeyValueInformation = NULL;
    OBJECT_ATTRIBUTES ObjectAttributes;
    HANDLE hDeviceMapKey = (HANDLE)-1;
    HANDLE hPortKey = (HANDLE)-1;
    ULONG Index = 0;
    ULONG Size, ResultLength;
    NTSTATUS Status;

    TRACE_(CLASS_NAME, "SearchForLegacyDrivers(%p %p %lu)\n",
        DriverObject, Context, Count);

    if (Count != 1)
        return;
    DriverExtension = (PCLASS_DRIVER_EXTENSION)Context;

    /* Create port base name, by replacing Class by Port at the end of the class base name */
    Status = DuplicateUnicodeString(
        RTL_DUPLICATE_UNICODE_STRING_NULL_TERMINATE,
        &DriverExtension->DeviceBaseName,
        &PortBaseName);
    if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "DuplicateUnicodeString() failed with status 0x%08lx\n", Status);
        goto cleanup;
    }
    PortBaseName.Length -= (sizeof(L"Class") - sizeof(UNICODE_NULL));
    RtlAppendUnicodeToString(&PortBaseName, L"Port");

    /* Allocate memory */
    Size = sizeof(KEY_VALUE_BASIC_INFORMATION) + MAX_PATH;
    KeyValueInformation = ExAllocatePoolWithTag(PagedPool, Size, CLASS_TAG);
    if (!KeyValueInformation)
    {
        WARN_(CLASS_NAME, "ExAllocatePoolWithTag() failed\n");
        Status = STATUS_NO_MEMORY;
        goto cleanup;
    }

    /* Open HKEY_LOCAL_MACHINE\HARDWARE\DEVICEMAP */
    InitializeObjectAttributes(&ObjectAttributes, &DeviceMapKeyU, OBJ_KERNEL_HANDLE | OBJ_CASE_INSENSITIVE, NULL, NULL);
    Status = ZwOpenKey(&hDeviceMapKey, 0, &ObjectAttributes);
    if (Status == STATUS_OBJECT_NAME_NOT_FOUND)
    {
        INFO_(CLASS_NAME, "HKLM\\HARDWARE\\DEVICEMAP is non-existent\n");
        Status = STATUS_SUCCESS;
        goto cleanup;
    }
    else if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "ZwOpenKey() failed with status 0x%08lx\n", Status);
        goto cleanup;
    }

    /* Open sub key */
    InitializeObjectAttributes(&ObjectAttributes, &PortBaseName, OBJ_KERNEL_HANDLE | OBJ_CASE_INSENSITIVE, hDeviceMapKey, NULL);
    Status = ZwOpenKey(&hPortKey, KEY_QUERY_VALUE, &ObjectAttributes);
    if (Status == STATUS_OBJECT_NAME_NOT_FOUND)
    {
        INFO_(CLASS_NAME, "HKLM\\HARDWARE\\DEVICEMAP\\%wZ is non-existent\n", &PortBaseName);
        Status = STATUS_SUCCESS;
        goto cleanup;
    }
    else if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "ZwOpenKey() failed with status 0x%08lx\n", Status);
        goto cleanup;
    }

    /* Read each value name */
    while (ZwEnumerateValueKey(hPortKey, Index++, KeyValueBasicInformation, KeyValueInformation, Size, &ResultLength) == STATUS_SUCCESS)
    {
        UNICODE_STRING PortName;
        PDEVICE_OBJECT PortDeviceObject = NULL;
        PFILE_OBJECT FileObject = NULL;

        PortName.Length = PortName.MaximumLength = (USHORT)KeyValueInformation->NameLength;
        PortName.Buffer = KeyValueInformation->Name;

        /* Open the device object pointer */
        Status = IoGetDeviceObjectPointer(&PortName, FILE_READ_ATTRIBUTES, &FileObject, &PortDeviceObject);
        if (!NT_SUCCESS(Status))
        {
            WARN_(CLASS_NAME, "IoGetDeviceObjectPointer(%wZ) failed with status 0x%08lx\n", &PortName, Status);
            continue;
        }
        INFO_(CLASS_NAME, "Legacy driver found\n");

        Status = ClassAddDevice(DriverObject, PortDeviceObject);
        if (!NT_SUCCESS(Status))
        {
            /* FIXME: Log the error */
            WARN_(CLASS_NAME, "ClassAddDevice() failed with status 0x%08lx\n", Status);
        }

        ObDereferenceObject(FileObject);
    }

cleanup:
    if (KeyValueInformation != NULL)
        ExFreePoolWithTag(KeyValueInformation, CLASS_TAG);
    if (hDeviceMapKey != (HANDLE)-1)
        ZwClose(hDeviceMapKey);
    if (hPortKey != (HANDLE)-1)
        ZwClose(hPortKey);
}

/*
 * Standard DriverEntry method.
 */
NTSTATUS NTAPI
DriverEntry(
    IN PDRIVER_OBJECT DriverObject,
    IN PUNICODE_STRING RegistryPath)
{
    PCLASS_DRIVER_EXTENSION DriverExtension;
    ULONG i;
    NTSTATUS Status;

    Status = IoAllocateDriverObjectExtension(
        DriverObject,
        DriverObject,
        sizeof(CLASS_DRIVER_EXTENSION),
        (PVOID*)&DriverExtension);
    if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "IoAllocateDriverObjectExtension() failed with status 0x%08lx\n", Status);
        return Status;
    }
    RtlZeroMemory(DriverExtension, sizeof(CLASS_DRIVER_EXTENSION));

    Status = DuplicateUnicodeString(
        RTL_DUPLICATE_UNICODE_STRING_NULL_TERMINATE,
        RegistryPath,
        &DriverExtension->RegistryPath);
    if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "DuplicateUnicodeString() failed with status 0x%08lx\n", Status);
        return Status;
    }

    Status = ReadRegistryEntries(RegistryPath, DriverExtension);
    if (!NT_SUCCESS(Status))
    {
        WARN_(CLASS_NAME, "ReadRegistryEntries() failed with status 0x%08lx\n", Status);
        return Status;
    }

    if (DriverExtension->ConnectMultiplePorts == 1)
    {
        Status = CreateClassDeviceObject(
            DriverObject,
            &DriverExtension->MainClassDeviceObject);
        if (!NT_SUCCESS(Status))
        {
            WARN_(CLASS_NAME, "CreateClassDeviceObject() failed with status 0x%08lx\n", Status);
            return Status;
        }
    }

    DriverObject->DriverExtension->AddDevice = ClassAddDevice;
    DriverObject->DriverUnload = DriverUnload;

    for (i = 0; i <= IRP_MJ_MAXIMUM_FUNCTION; i++)
        DriverObject->MajorFunction[i] = IrpStub;

    DriverObject->MajorFunction[IRP_MJ_CREATE]         = ClassCreate;
    DriverObject->MajorFunction[IRP_MJ_CLOSE]          = ClassClose;
    DriverObject->MajorFunction[IRP_MJ_CLEANUP]        = ClassCleanup;
    DriverObject->MajorFunction[IRP_MJ_READ]           = ClassRead;
    DriverObject->MajorFunction[IRP_MJ_PNP]            = ClassPnp;
    DriverObject->MajorFunction[IRP_MJ_DEVICE_CONTROL] = ClassDeviceControl;
    DriverObject->MajorFunction[IRP_MJ_INTERNAL_DEVICE_CONTROL] = ForwardIrpAndForget;
    DriverObject->DriverStartIo                        = ClassStartIo;

    /* We will detect the legacy devices later */
    IoRegisterDriverReinitialization(
        DriverObject,
        SearchForLegacyDrivers,
        DriverExtension);

    return STATUS_SUCCESS;
}