/drivers/storage/classpnp/class.c

Large files files are truncated, but you can click here to view the full file

/*++

Copyright (C) Microsoft Corporation, 1991 - 1999

Module Name:

    class.c

Abstract:

    SCSI class driver routines

Environment:

    kernel mode only

Notes:


Revision History:

--*/

#define CLASS_INIT_GUID 1
#include "classp.h"
#include "debug.h"

#ifdef ALLOC_PRAGMA
    #pragma alloc_text(INIT, DriverEntry)
    #pragma alloc_text(PAGE, ClassAddDevice)
    #pragma alloc_text(PAGE, ClassClaimDevice)
    #pragma alloc_text(PAGE, ClassCreateDeviceObject)
    #pragma alloc_text(PAGE, ClassDispatchPnp)
    #pragma alloc_text(PAGE, ClassGetDescriptor)
    #pragma alloc_text(PAGE, ClassGetPdoId)
    #pragma alloc_text(PAGE, ClassInitialize)
    #pragma alloc_text(PAGE, ClassInitializeEx)
    #pragma alloc_text(PAGE, ClassInvalidateBusRelations)
    #pragma alloc_text(PAGE, ClassMarkChildMissing)
    #pragma alloc_text(PAGE, ClassMarkChildrenMissing)
    #pragma alloc_text(PAGE, ClassModeSense)
    #pragma alloc_text(PAGE, ClassPnpQueryFdoRelations)
    #pragma alloc_text(PAGE, ClassPnpStartDevice)
    #pragma alloc_text(PAGE, ClassQueryPnpCapabilities)
    #pragma alloc_text(PAGE, ClassQueryTimeOutRegistryValue)
    #pragma alloc_text(PAGE, ClassRemoveDevice)
    #pragma alloc_text(PAGE, ClassRetrieveDeviceRelations)
    #pragma alloc_text(PAGE, ClassUpdateInformationInRegistry)
    #pragma alloc_text(PAGE, ClassSendDeviceIoControlSynchronous)
    #pragma alloc_text(PAGE, ClassUnload)
    #pragma alloc_text(PAGE, ClasspAllocateReleaseRequest)
    #pragma alloc_text(PAGE, ClasspFreeReleaseRequest)
    #pragma alloc_text(PAGE, ClasspInitializeHotplugInfo)
    #pragma alloc_text(PAGE, ClasspRegisterMountedDeviceInterface)
    #pragma alloc_text(PAGE, ClasspScanForClassHacks)
    #pragma alloc_text(PAGE, ClasspScanForSpecialInRegistry)
#endif

ULONG ClassPnpAllowUnload = TRUE;


#define FirstDriveLetter 'C'
#define LastDriveLetter  'Z'



/*++////////////////////////////////////////////////////////////////////////////

DriverEntry()

Routine Description:

    Temporary entry point needed to initialize the class system dll.
    It doesn't do anything.

Arguments:

    DriverObject - Pointer to the driver object created by the system.

Return Value:

   STATUS_SUCCESS

--*/
NTSTATUS
NTAPI
DriverEntry(
    IN PDRIVER_OBJECT DriverObject,
    IN PUNICODE_STRING RegistryPath
    )
{
    return STATUS_SUCCESS;
}




/*++////////////////////////////////////////////////////////////////////////////

ClassInitialize()

Routine Description:

    This routine is called by a class driver during its
    DriverEntry routine to initialize the driver.

Arguments:

    Argument1          - Driver Object.
    Argument2          - Registry Path.
    InitializationData - Device-specific driver's initialization data.

Return Value:

    A valid return code for a DriverEntry routine.

--*/
ULONG
ClassInitialize(
    IN  PVOID            Argument1,
    IN  PVOID            Argument2,
    IN  PCLASS_INIT_DATA InitializationData
    )
{
    PDRIVER_OBJECT  DriverObject = Argument1;
    PUNICODE_STRING RegistryPath = Argument2;

    PCLASS_DRIVER_EXTENSION driverExtension;

    NTSTATUS        status;

    PAGED_CODE();
    
    DebugPrint((3,"\n\nSCSI Class Driver\n"));

    ClasspInitializeDebugGlobals();

    //
    // Validate the length of this structure. This is effectively a
    // version check.
    //

    if (InitializationData->InitializationDataSize != sizeof(CLASS_INIT_DATA)) {

        //
        // This DebugPrint is to help third-party driver writers
        //

        DebugPrint((0,"ClassInitialize: Class driver wrong version\n"));
        return (ULONG) STATUS_REVISION_MISMATCH;
    }

    //
    // Check that each required entry is not NULL. Note that Shutdown, Flush and Error
    // are not required entry points.
    //

    if ((!InitializationData->FdoData.ClassDeviceControl) ||
        (!((InitializationData->FdoData.ClassReadWriteVerification) ||
           (InitializationData->ClassStartIo))) ||
        (!InitializationData->ClassAddDevice) ||
        (!InitializationData->FdoData.ClassStartDevice)) {

        //
        // This DebugPrint is to help third-party driver writers
        //

        DebugPrint((0,
            "ClassInitialize: Class device-specific driver missing required "
            "FDO entry\n"));

        return (ULONG) STATUS_REVISION_MISMATCH;
    }

    if ((InitializationData->ClassEnumerateDevice) &&
        ((!InitializationData->PdoData.ClassDeviceControl) ||
         (!InitializationData->PdoData.ClassStartDevice) ||
         (!((InitializationData->PdoData.ClassReadWriteVerification) ||
            (InitializationData->ClassStartIo))))) {

        //
        // This DebugPrint is to help third-party driver writers
        //

        DebugPrint((0, "ClassInitialize: Class device-specific missing "
                       "required PDO entry\n"));

        return (ULONG) STATUS_REVISION_MISMATCH;
    }

    if((InitializationData->FdoData.ClassStopDevice == NULL) ||
        ((InitializationData->ClassEnumerateDevice != NULL) &&
         (InitializationData->PdoData.ClassStopDevice == NULL))) {

        //
        // This DebugPrint is to help third-party driver writers
        //

        DebugPrint((0, "ClassInitialize: Class device-specific missing "
                       "required PDO entry\n"));
        ASSERT(FALSE);
        return (ULONG) STATUS_REVISION_MISMATCH;
    }

    //
    // Setup the default power handlers if the class driver didn't provide
    // any.
    //

    if(InitializationData->FdoData.ClassPowerDevice == NULL) {
        InitializationData->FdoData.ClassPowerDevice = ClassMinimalPowerHandler;
    }

    if((InitializationData->ClassEnumerateDevice != NULL) &&
       (InitializationData->PdoData.ClassPowerDevice == NULL)) {
        InitializationData->PdoData.ClassPowerDevice = ClassMinimalPowerHandler;
    }

    //
    // warn that unload is not supported
    //
    // ISSUE-2000/02/03-peterwie
    // We should think about making this a fatal error.
    //

    if(InitializationData->ClassUnload == NULL) {

        //
        // This DebugPrint is to help third-party driver writers
        //

        DebugPrint((0, "ClassInitialize: driver does not support unload %wZ\n",
                    RegistryPath));
    }

    //
    // Create an extension for the driver object
    //

    status = IoAllocateDriverObjectExtension(DriverObject,
                                             CLASS_DRIVER_EXTENSION_KEY,
                                             sizeof(CLASS_DRIVER_EXTENSION),
                                             &driverExtension);

    if(NT_SUCCESS(status)) {

        //
        // Copy the registry path into the driver extension so we can use it later
        //

        driverExtension->RegistryPath.Length = RegistryPath->Length;
        driverExtension->RegistryPath.MaximumLength = RegistryPath->MaximumLength;

        driverExtension->RegistryPath.Buffer =
            ExAllocatePoolWithTag(PagedPool,
                                  RegistryPath->MaximumLength,
                                  '1CcS');

        if(driverExtension->RegistryPath.Buffer == NULL) {

            status = STATUS_INSUFFICIENT_RESOURCES;
            return status;
        }

        RtlCopyUnicodeString(
            &(driverExtension->RegistryPath),
            RegistryPath);

        //
        // Copy the initialization data into the driver extension so we can reuse
        // it during our add device routine
        //

        RtlCopyMemory(
            &(driverExtension->InitData),
            InitializationData,
            sizeof(CLASS_INIT_DATA));

        driverExtension->DeviceCount = 0;

    } else if (status == STATUS_OBJECT_NAME_COLLISION) {

        //
        // The extension already exists - get a pointer to it
        //

        driverExtension = IoGetDriverObjectExtension(DriverObject,
                                                     CLASS_DRIVER_EXTENSION_KEY);

        ASSERT(driverExtension != NULL);

    } else {

        DebugPrint((1, "ClassInitialize: Class driver extension could not be "
                       "allocated %lx\n", status));
        return status;
    }

    //
    // Update driver object with entry points.
    //

    DriverObject->MajorFunction[IRP_MJ_CREATE] = ClassCreateClose;
    DriverObject->MajorFunction[IRP_MJ_CLOSE] = ClassCreateClose;
    DriverObject->MajorFunction[IRP_MJ_READ] = ClassReadWrite;
    DriverObject->MajorFunction[IRP_MJ_WRITE] = ClassReadWrite;
    DriverObject->MajorFunction[IRP_MJ_SCSI] = ClassInternalIoControl;
    DriverObject->MajorFunction[IRP_MJ_DEVICE_CONTROL] = ClassDeviceControlDispatch;
    DriverObject->MajorFunction[IRP_MJ_SHUTDOWN] = ClassShutdownFlush;
    DriverObject->MajorFunction[IRP_MJ_FLUSH_BUFFERS] = ClassShutdownFlush;
    DriverObject->MajorFunction[IRP_MJ_PNP] = ClassDispatchPnp;
    DriverObject->MajorFunction[IRP_MJ_POWER] = ClassDispatchPower;
    DriverObject->MajorFunction[IRP_MJ_SYSTEM_CONTROL] = ClassSystemControl;

    if (InitializationData->ClassStartIo) {
        DriverObject->DriverStartIo = ClasspStartIo;
    }

    if ((InitializationData->ClassUnload) && (ClassPnpAllowUnload == TRUE)) {
        DriverObject->DriverUnload = ClassUnload;
    } else {
        DriverObject->DriverUnload = NULL;
    }

    DriverObject->DriverExtension->AddDevice = ClassAddDevice;

    DbgPrint("Driver is ready to go\n");
    status = STATUS_SUCCESS;
    return status;
} // end ClassInitialize()

/*++////////////////////////////////////////////////////////////////////////////

ClassInitializeEx()

Routine Description:

    This routine is allows the caller to do any extra initialization or
    setup that is not done in ClassInitialize. The operation is
    controlled by the GUID that is passed and the contents of the Data
    parameter is dependent upon the GUID.

    This is the list of supported operations:

    Guid - GUID_CLASSPNP_QUERY_REGINFOEX
    Data - A PCLASS_QUERY_WMI_REGINFO_EX callback function pointer

        Initialized classpnp to callback a PCLASS_QUERY_WMI_REGINFO_EX
        callback instead of a PCLASS_QUERY_WMI_REGINFO callback. The
        former callback allows the driver to specify the name of the
        mof resource.

Arguments:

    DriverObject
    Guid
    Data

Return Value:

    Status Code

--*/
ULONG
ClassInitializeEx(
    IN  PDRIVER_OBJECT   DriverObject,
    IN  LPGUID           Guid,
    IN  PVOID            Data
    )
{
    PCLASS_DRIVER_EXTENSION driverExtension;

    NTSTATUS        status;

    PAGED_CODE();

    driverExtension = IoGetDriverObjectExtension( DriverObject,
                                                  CLASS_DRIVER_EXTENSION_KEY
                                                  );
    if (IsEqualGUID(Guid, &ClassGuidQueryRegInfoEx))
    {
        PCLASS_QUERY_WMI_REGINFO_EX_LIST List;

        //
        // Indicate the device supports PCLASS_QUERY_REGINFO_EX
        // callback instead of PCLASS_QUERY_REGINFO callback.
        //
        List = (PCLASS_QUERY_WMI_REGINFO_EX_LIST)Data;

        if (List->Size == sizeof(CLASS_QUERY_WMI_REGINFO_EX_LIST))
        {
            driverExtension->ClassFdoQueryWmiRegInfoEx = List->ClassFdoQueryWmiRegInfoEx;
            driverExtension->ClassPdoQueryWmiRegInfoEx = List->ClassPdoQueryWmiRegInfoEx;
            status = STATUS_SUCCESS;
        } else {
            status = STATUS_INVALID_PARAMETER;
        }
    } else {
        status = STATUS_NOT_SUPPORTED;
    }

    return(status);

} // end ClassInitializeEx()

/*++////////////////////////////////////////////////////////////////////////////

ClassUnload()

Routine Description:

    called when there are no more references to the driver.  this allows
    drivers to be updated without rebooting.

Arguments:

    DriverObject - a pointer to the driver object that is being unloaded

Status:

--*/
VOID
ClassUnload(
    IN PDRIVER_OBJECT DriverObject
    )
{
    PCLASS_DRIVER_EXTENSION driverExtension;
    NTSTATUS status;

    PAGED_CODE();

    ASSERT( DriverObject->DeviceObject == NULL );

    driverExtension = IoGetDriverObjectExtension( DriverObject,
                                                  CLASS_DRIVER_EXTENSION_KEY
                                                  );

    ASSERT(driverExtension != NULL);
    ASSERT(driverExtension->RegistryPath.Buffer != NULL);
    ASSERT(driverExtension->InitData.ClassUnload != NULL);

    DebugPrint((1, "ClassUnload: driver unloading %wZ\n",
                &driverExtension->RegistryPath));

    //
    // attempt to process the driver's unload routine first.
    //

    driverExtension->InitData.ClassUnload(DriverObject);

    //
    // free own allocated resources and return
    //

    ExFreePool( driverExtension->RegistryPath.Buffer );
    driverExtension->RegistryPath.Buffer = NULL;
    driverExtension->RegistryPath.Length = 0;
    driverExtension->RegistryPath.MaximumLength = 0;

    return;
} // end ClassUnload()

/*++////////////////////////////////////////////////////////////////////////////

ClassAddDevice()

Routine Description:

    SCSI class driver add device routine.  This is called by pnp when a new
    physical device come into being.

    This routine will call out to the class driver to verify that it should
    own this device then will create and attach a device object and then hand
    it to the driver to initialize and create symbolic links

Arguments:

    DriverObject - a pointer to the driver object that this is being created for
    PhysicalDeviceObject - a pointer to the physical device object

Status: STATUS_NO_SUCH_DEVICE if the class driver did not want this device
    STATUS_SUCCESS if the creation and attachment was successful
    status of device creation and initialization

--*/
NTSTATUS
ClassAddDevice(
    IN PDRIVER_OBJECT DriverObject,
    IN PDEVICE_OBJECT PhysicalDeviceObject
    )
{
    PCLASS_DRIVER_EXTENSION driverExtension =
        IoGetDriverObjectExtension(DriverObject,
                                   CLASS_DRIVER_EXTENSION_KEY);

    NTSTATUS status;

    PAGED_CODE();

    DbgPrint("got a device\n");
    status = driverExtension->InitData.ClassAddDevice(DriverObject,
                                                      PhysicalDeviceObject);
    return status;
} // end ClassAddDevice()

/*++////////////////////////////////////////////////////////////////////////////

ClassDispatchPnp()

Routine Description:

    Storage class driver pnp routine.  This is called by the io system when
    a PNP request is sent to the device.

Arguments:

    DeviceObject - pointer to the device object

    Irp - pointer to the io request packet

Return Value:

    status

--*/
NTSTATUS
ClassDispatchPnp(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    )
{
    PCOMMON_DEVICE_EXTENSION commonExtension = DeviceObject->DeviceExtension;
    BOOLEAN isFdo = commonExtension->IsFdo;

    PCLASS_DRIVER_EXTENSION driverExtension;
    PCLASS_INIT_DATA initData;
    PCLASS_DEV_INFO devInfo;

    PIO_STACK_LOCATION irpStack = IoGetCurrentIrpStackLocation(Irp);
    PIO_STACK_LOCATION nextIrpStack = IoGetNextIrpStackLocation(Irp);

    NTSTATUS status = Irp->IoStatus.Status;
    BOOLEAN completeRequest = TRUE;
    BOOLEAN lockReleased = FALSE;

    ULONG isRemoved;

    PAGED_CODE();

    //
    // Extract all the useful information out of the driver object
    // extension
    //

    driverExtension = IoGetDriverObjectExtension(DeviceObject->DriverObject,
                                                 CLASS_DRIVER_EXTENSION_KEY);
    if (driverExtension){

        initData = &(driverExtension->InitData);

        if(isFdo) {
            devInfo = &(initData->FdoData);
        } else {
            devInfo = &(initData->PdoData);
        }

        isRemoved = ClassAcquireRemoveLock(DeviceObject, Irp);

        DebugPrint((2, "ClassDispatchPnp (%p,%p): minor code %#x for %s %p\n",
                       DeviceObject, Irp,
                       irpStack->MinorFunction,
                       isFdo ? "fdo" : "pdo",
                       DeviceObject));
        DebugPrint((2, "ClassDispatchPnp (%p,%p): previous %#x, current %#x\n",
                       DeviceObject, Irp,
                       commonExtension->PreviousState,
                       commonExtension->CurrentState));

        switch(irpStack->MinorFunction) {

            case IRP_MN_START_DEVICE: {

                //
                // if this is sent to the FDO we should forward it down the
                // attachment chain before we start the FDO.
                //

                if (isFdo) {
                    status = ClassForwardIrpSynchronous(commonExtension, Irp);
                }
                else {
                    status = STATUS_SUCCESS;
                }

                if (NT_SUCCESS(status)){
                    status = Irp->IoStatus.Status = ClassPnpStartDevice(DeviceObject);
                }

                break;
            }


            case IRP_MN_QUERY_DEVICE_RELATIONS: {

                DEVICE_RELATION_TYPE type =
                    irpStack->Parameters.QueryDeviceRelations.Type;

                PDEVICE_RELATIONS deviceRelations = NULL;

                if(!isFdo) {

                    if(type == TargetDeviceRelation) {

                        //
                        // Device relations has one entry built in to it's size.
                        //

                        status = STATUS_INSUFFICIENT_RESOURCES;

                        deviceRelations = ExAllocatePoolWithTag(PagedPool,
                                                         sizeof(DEVICE_RELATIONS),
                                                         '2CcS');

                        if(deviceRelations != NULL) {

                            RtlZeroMemory(deviceRelations,
                                          sizeof(DEVICE_RELATIONS));

                            Irp->IoStatus.Information = (ULONG_PTR) deviceRelations;

                            deviceRelations->Count = 1;
                            deviceRelations->Objects[0] = DeviceObject;
                            ObReferenceObject(deviceRelations->Objects[0]);

                            status = STATUS_SUCCESS;
                        }

                    } else {
                        //
                        // PDO's just complete enumeration requests without altering
                        // the status.
                        //

                        status = Irp->IoStatus.Status;
                    }

                    break;

                } else if (type == BusRelations) {

                    ASSERT(commonExtension->IsInitialized);

                    //
                    // Make sure we support enumeration
                    //

                    if(initData->ClassEnumerateDevice == NULL) {

                        //
                        // Just send the request down to the lower driver.  Perhaps
                        // It can enumerate children.
                        //

                    } else {

                        //
                        // Re-enumerate the device
                        //

                        status = ClassPnpQueryFdoRelations(DeviceObject, Irp);

                        if(!NT_SUCCESS(status)) {
                            completeRequest = TRUE;
                            break;
                        }
                    }
                }

                IoCopyCurrentIrpStackLocationToNext(Irp);
                ClassReleaseRemoveLock(DeviceObject, Irp);
                status = IoCallDriver(commonExtension->LowerDeviceObject, Irp);
                completeRequest = FALSE;

                break;
            }

            case IRP_MN_QUERY_ID: {

                BUS_QUERY_ID_TYPE idType = irpStack->Parameters.QueryId.IdType;
                UNICODE_STRING unicodeString;

                if(isFdo) {

                    //
                    // FDO's should just forward the query down to the lower
                    // device objects
                    //

                    IoCopyCurrentIrpStackLocationToNext(Irp);
                    ClassReleaseRemoveLock(DeviceObject, Irp);

                    status = IoCallDriver(commonExtension->LowerDeviceObject, Irp);
                    completeRequest = FALSE;
                    break;
                }

                //
                // PDO's need to give an answer - this is easy for now
                //

                RtlInitUnicodeString(&unicodeString, NULL);

                status = ClassGetPdoId(DeviceObject,
                                       idType,
                                       &unicodeString);

                if(status == STATUS_NOT_IMPLEMENTED) {
                    //
                    // The driver doesn't implement this ID (whatever it is).
                    // Use the status out of the IRP so that we don't mangle a
                    // response from someone else.
                    //

                    status = Irp->IoStatus.Status;
                } else if(NT_SUCCESS(status)) {
                    Irp->IoStatus.Information = (ULONG_PTR) unicodeString.Buffer;
                } else {
                    Irp->IoStatus.Information = (ULONG_PTR) NULL;
                }

                break;
            }

            case IRP_MN_QUERY_STOP_DEVICE:
            case IRP_MN_QUERY_REMOVE_DEVICE: {

                DebugPrint((2, "ClassDispatchPnp (%p,%p): Processing QUERY_%s irp\n",
                            DeviceObject, Irp,
                            ((irpStack->MinorFunction == IRP_MN_QUERY_STOP_DEVICE) ?
                             "STOP" : "REMOVE")));

                //
                // If this device is in use for some reason (paging, etc...)
                // then we need to fail the request.
                //

                if(commonExtension->PagingPathCount != 0) {

                    DebugPrint((1, "ClassDispatchPnp (%p,%p): device is in paging "
                                "path and cannot be removed\n",
                                DeviceObject, Irp));
                    status = STATUS_DEVICE_BUSY;
                    break;
                }

                //
                // Check with the class driver to see if the query operation
                // can succeed.
                //

                if(irpStack->MinorFunction == IRP_MN_QUERY_STOP_DEVICE) {
                    status = devInfo->ClassStopDevice(DeviceObject,
                                                      irpStack->MinorFunction);
                } else {
                    status = devInfo->ClassRemoveDevice(DeviceObject,
                                                        irpStack->MinorFunction);
                }

                if(NT_SUCCESS(status)) {

                    //
                    // ASSERT that we never get two queries in a row, as
                    // this will severly mess up the state machine
                    //
                    ASSERT(commonExtension->CurrentState != irpStack->MinorFunction);
                    commonExtension->PreviousState = commonExtension->CurrentState;
                    commonExtension->CurrentState = irpStack->MinorFunction;

                    if(isFdo) {
                        DebugPrint((2, "ClassDispatchPnp (%p,%p): Forwarding QUERY_"
                                    "%s irp\n", DeviceObject, Irp,
                                    ((irpStack->MinorFunction == IRP_MN_QUERY_STOP_DEVICE) ?
                                     "STOP" : "REMOVE")));
                        status = ClassForwardIrpSynchronous(commonExtension, Irp);
                    }
                }
                DebugPrint((2, "ClassDispatchPnp (%p,%p): Final status == %x\n",
                            DeviceObject, Irp, status));

                break;
            }

            case IRP_MN_CANCEL_STOP_DEVICE:
            case IRP_MN_CANCEL_REMOVE_DEVICE: {

                //
                // Check with the class driver to see if the query or cancel
                // operation can succeed.
                //

                if(irpStack->MinorFunction == IRP_MN_CANCEL_STOP_DEVICE) {
                    status = devInfo->ClassStopDevice(DeviceObject,
                                                      irpStack->MinorFunction);
                    ASSERTMSG("ClassDispatchPnp !! CANCEL_STOP_DEVICE should "
                              "never be failed\n", NT_SUCCESS(status));
                } else {
                    status = devInfo->ClassRemoveDevice(DeviceObject,
                                                        irpStack->MinorFunction);
                    ASSERTMSG("ClassDispatchPnp !! CANCEL_REMOVE_DEVICE should "
                              "never be failed\n", NT_SUCCESS(status));
                }

                Irp->IoStatus.Status = status;

                //
                // We got a CANCEL - roll back to the previous state only
                // if the current state is the respective QUERY state.
                //

                if(((irpStack->MinorFunction == IRP_MN_CANCEL_STOP_DEVICE) &&
                    (commonExtension->CurrentState == IRP_MN_QUERY_STOP_DEVICE)
                    ) ||
                   ((irpStack->MinorFunction == IRP_MN_CANCEL_REMOVE_DEVICE) &&
                    (commonExtension->CurrentState == IRP_MN_QUERY_REMOVE_DEVICE)
                    )
                   ) {

                    commonExtension->CurrentState =
                        commonExtension->PreviousState;
                    commonExtension->PreviousState = 0xff;

                }

                if(isFdo) {
                    IoCopyCurrentIrpStackLocationToNext(Irp);
                    ClassReleaseRemoveLock(DeviceObject, Irp);
                    status = IoCallDriver(commonExtension->LowerDeviceObject, Irp);
                    completeRequest = FALSE;
                } else {
                    status = STATUS_SUCCESS;
                }

                break;
            }

            case IRP_MN_STOP_DEVICE: {

                //
                // These all mean nothing to the class driver currently.  The
                // port driver will handle all queueing when necessary.
                //

                DebugPrint((2, "ClassDispatchPnp (%p,%p): got stop request for %s\n",
                            DeviceObject, Irp,
                            (isFdo ? "fdo" : "pdo")
                            ));

                ASSERT(commonExtension->PagingPathCount == 0);

                //
                // ISSUE-2000/02/03-peterwie
                // if we stop the timer here then it means no class driver can
                // do i/o in its ClassStopDevice routine.  This is because the
                // retry (among other things) is tied into the tick handler
                // and disabling retries could cause the class driver to deadlock.
                // Currently no class driver we're aware of issues i/o in its
                // Stop routine but this is a case we may want to defend ourself
                // against.
                //

                if (DeviceObject->Timer) {
                    IoStopTimer(DeviceObject);
                }

                status = devInfo->ClassStopDevice(DeviceObject, IRP_MN_STOP_DEVICE);

                ASSERTMSG("ClassDispatchPnp !! STOP_DEVICE should "
                          "never be failed\n", NT_SUCCESS(status));

                if(isFdo) {
                    status = ClassForwardIrpSynchronous(commonExtension, Irp);
                }

                if(NT_SUCCESS(status)) {
                    commonExtension->CurrentState = irpStack->MinorFunction;
                    commonExtension->PreviousState = 0xff;
                }

                break;
            }

            case IRP_MN_REMOVE_DEVICE:
            case IRP_MN_SURPRISE_REMOVAL: {

                PDEVICE_OBJECT lowerDeviceObject = commonExtension->LowerDeviceObject;
                UCHAR removeType = irpStack->MinorFunction;

                if (commonExtension->PagingPathCount != 0) {
                    DBGTRACE(ClassDebugWarning, ("ClassDispatchPnp (%p,%p): paging device is getting removed!", DeviceObject, Irp));
                }

                //
                // Release the lock for this IRP before calling in.
                //
                ClassReleaseRemoveLock(DeviceObject, Irp);
                lockReleased = TRUE;

                /*
                 *  If a timer was started on the device, stop it.
                 */
                if (DeviceObject->Timer) {
                    IoStopTimer(DeviceObject);
                }

                /*
                 *  "Fire-and-forget" the remove irp to the lower stack.
                 *  Don't touch the irp (or the irp stack!) after this.
                 */
                if (isFdo) {
                    IoCopyCurrentIrpStackLocationToNext(Irp);
                    status = IoCallDriver(commonExtension->LowerDeviceObject, Irp);
                    ASSERT(NT_SUCCESS(status));
                    completeRequest = FALSE;
                }
                else {
                    status = STATUS_SUCCESS;
                }

                /*
                 *  Do our own cleanup and call the class driver's remove
                 *  cleanup routine.
                 *  For IRP_MN_REMOVE_DEVICE, this also deletes our device object,
                 *  so don't touch the extension after this.
                 */
                commonExtension->PreviousState = commonExtension->CurrentState;
                commonExtension->CurrentState = removeType;
                ClassRemoveDevice(DeviceObject, removeType);

                break;
            }

            case IRP_MN_DEVICE_USAGE_NOTIFICATION: {

                switch(irpStack->Parameters.UsageNotification.Type) {

                    case DeviceUsageTypePaging: {

                        BOOLEAN setPagable;

                        if((irpStack->Parameters.UsageNotification.InPath) &&
                           (commonExtension->CurrentState != IRP_MN_START_DEVICE)) {

                            //
                            // Device isn't started.  Don't allow adding a
                            // paging file, but allow a removal of one.
                            //

                            status = STATUS_DEVICE_NOT_READY;
                            break;
                        }

                        ASSERT(commonExtension->IsInitialized);

                        //
                        // need to synchronize this now...
                        //

                        KeEnterCriticalRegion();
                        status = KeWaitForSingleObject(&commonExtension->PathCountEvent,
                                                       Executive, KernelMode,
                                                       FALSE, NULL);
                        ASSERT(NT_SUCCESS(status));
                        status = STATUS_SUCCESS;

                        //
                        // If the volume is removable we should try to lock it in
                        // place or unlock it once per paging path count
                        //

                        if (commonExtension->IsFdo){
                            status = ClasspEjectionControl(
                                            DeviceObject,
                                            Irp,
                                            InternalMediaLock,
                                            (BOOLEAN)irpStack->Parameters.UsageNotification.InPath);
                        }

                        if (!NT_SUCCESS(status)){
                            KeSetEvent(&commonExtension->PathCountEvent, IO_NO_INCREMENT, FALSE);
                            KeLeaveCriticalRegion();
                            break;
                        }

                        //
                        // if removing last paging device, need to set DO_POWER_PAGABLE
                        // bit here, and possible re-set it below on failure.
                        //

                        setPagable = FALSE;

                        if (!irpStack->Parameters.UsageNotification.InPath &&
                            commonExtension->PagingPathCount == 1
                            ) {

                            //
                            // removing last paging file
                            // must have DO_POWER_PAGABLE bits set, but only
                            // if noone set the DO_POWER_INRUSH bit
                            //


                            if (TEST_FLAG(DeviceObject->Flags, DO_POWER_INRUSH)) {
                                DebugPrint((2, "ClassDispatchPnp (%p,%p): Last "
                                            "paging file removed, but "
                                            "DO_POWER_INRUSH was set, so NOT "
                                            "setting DO_POWER_PAGABLE\n",
                                            DeviceObject, Irp));
                            } else {
                                DebugPrint((2, "ClassDispatchPnp (%p,%p): Last "
                                            "paging file removed, "
                                            "setting DO_POWER_PAGABLE\n",
                                            DeviceObject, Irp));
                                SET_FLAG(DeviceObject->Flags, DO_POWER_PAGABLE);
                                setPagable = TRUE;
                            }

                        }

                        //
                        // forward the irp before finishing handling the
                        // special cases
                        //

                        status = ClassForwardIrpSynchronous(commonExtension, Irp);

                        //
                        // now deal with the failure and success cases.
                        // note that we are not allowed to fail the irp
                        // once it is sent to the lower drivers.
                        //

                        if (NT_SUCCESS(status)) {

                            IoAdjustPagingPathCount(
                                &commonExtension->PagingPathCount,
                                irpStack->Parameters.UsageNotification.InPath);

                            if (irpStack->Parameters.UsageNotification.InPath) {
                                if (commonExtension->PagingPathCount == 1) {
                                    DebugPrint((2, "ClassDispatchPnp (%p,%p): "
                                                "Clearing PAGABLE bit\n",
                                                DeviceObject, Irp));
                                    CLEAR_FLAG(DeviceObject->Flags, DO_POWER_PAGABLE);
                                }
                            }

                        } else {

                            //
                            // cleanup the changes done above
                            //

                            if (setPagable == TRUE) {
                                DebugPrint((2, "ClassDispatchPnp (%p,%p): Unsetting "
                                            "PAGABLE bit due to irp failure\n",
                                            DeviceObject, Irp));
                                CLEAR_FLAG(DeviceObject->Flags, DO_POWER_PAGABLE);
                                setPagable = FALSE;
                            }

                            //
                            // relock or unlock the media if needed.
                            //

                            if (commonExtension->IsFdo) {

                                ClasspEjectionControl(
                                        DeviceObject,
                                        Irp,
                                        InternalMediaLock,
                                        (BOOLEAN)!irpStack->Parameters.UsageNotification.InPath);
                            }
                        }

                        //
                        // set the event so the next one can occur.
                        //

                        KeSetEvent(&commonExtension->PathCountEvent,
                                   IO_NO_INCREMENT, FALSE);
                        KeLeaveCriticalRegion();
                        break;
                    }

                    case DeviceUsageTypeHibernation: {

                        IoAdjustPagingPathCount(
                            &commonExtension->HibernationPathCount,
                            irpStack->Parameters.UsageNotification.InPath
                            );
                        status = ClassForwardIrpSynchronous(commonExtension, Irp);
                        if (!NT_SUCCESS(status)) {
                            IoAdjustPagingPathCount(
                                &commonExtension->HibernationPathCount,
                                !irpStack->Parameters.UsageNotification.InPath
                                );
                        }

                        break;
                    }

                    case DeviceUsageTypeDumpFile: {
                        IoAdjustPagingPathCount(
                            &commonExtension->DumpPathCount,
                            irpStack->Parameters.UsageNotification.InPath
                            );
                        status = ClassForwardIrpSynchronous(commonExtension, Irp);
                        if (!NT_SUCCESS(status)) {
                            IoAdjustPagingPathCount(
                                &commonExtension->DumpPathCount,
                                !irpStack->Parameters.UsageNotification.InPath
                                );
                        }

                        break;
                    }

                    default: {
                        status = STATUS_INVALID_PARAMETER;
                        break;
                    }
                }
                break;
            }

            case IRP_MN_QUERY_CAPABILITIES: {

                DebugPrint((2, "ClassDispatchPnp (%p,%p): QueryCapabilities\n",
                            DeviceObject, Irp));

                if(!isFdo) {

                    status = ClassQueryPnpCapabilities(
                                DeviceObject,
                                irpStack->Parameters.DeviceCapabilities.Capabilities
                                );

                    break;

                } else {

                    PDEVICE_CAPABILITIES deviceCapabilities;
                    PFUNCTIONAL_DEVICE_EXTENSION fdoExtension;
                    PCLASS_PRIVATE_FDO_DATA fdoData;

                    fdoExtension = DeviceObject->DeviceExtension;
                    fdoData = fdoExtension->PrivateFdoData;
                    deviceCapabilities =
                        irpStack->Parameters.DeviceCapabilities.Capabilities;

                    //
                    // forward the irp before handling the special cases
                    //

                    status = ClassForwardIrpSynchronous(commonExtension, Irp);
                    if (!NT_SUCCESS(status)) {
                        break;
                    }

                    //
                    // we generally want to remove the device from the hotplug
                    // applet, which requires the SR-OK bit to be set.
                    // only when the user specifies that they are capable of
                    // safely removing things do we want to clear this bit
                    // (saved in WriteCacheEnableOverride)
                    //
                    // setting of this bit is done either above, or by the
                    // lower driver.
                    //
                    // note: may not be started, so check we have FDO data first.
                    //

                    if (fdoData &&
                        fdoData->HotplugInfo.WriteCacheEnableOverride) {
                        if (deviceCapabilities->SurpriseRemovalOK) {
                            DebugPrint((1, "Classpnp: Clearing SR-OK bit in "
                                        "device capabilities due to hotplug "
                                        "device or media\n"));
                        }
                        deviceCapabilities->SurpriseRemovalOK = FALSE;
                    }
                    break;

                } // end QUERY_CAPABILITIES for FDOs

                ASSERT(FALSE);
                break;


            } // end QUERY_CAPABILITIES

            default: {

                if (isFdo){
                    IoCopyCurrentIrpStackLocationToNext(Irp);

                    ClassReleaseRemoveLock(DeviceObject, Irp);
                    status = IoCallDriver(commonExtension->LowerDeviceObject, Irp);

                    completeRequest = FALSE;
                }

                break;
            }
        }
    }
    else {
        ASSERT(driverExtension);
        status = STATUS_INTERNAL_ERROR;
    }

    if (completeRequest){
        Irp->IoStatus.Status = status;

        if (!lockReleased){
            ClassReleaseRemoveLock(DeviceObject, Irp);
        }

        ClassCompleteRequest(DeviceObject, Irp, IO_NO_INCREMENT);

        DBGTRACE(ClassDebugTrace, ("ClassDispatchPnp (%p,%p): leaving with previous %#x, current %#x.", DeviceObject, Irp, commonExtension->PreviousState, commonExtension->CurrentState));
    }
    else {
        /*
         *  The irp is already completed so don't touch it.
         *  This may be a remove so don't touch the device extension.
         */
        DBGTRACE(ClassDebugTrace, ("ClassDispatchPnp (%p,%p): leaving.", DeviceObject, Irp));
    }

    return status;
} // end ClassDispatchPnp()

/*++////////////////////////////////////////////////////////////////////////////

ClassPnpStartDevice()

Routine Description:

    Storage class driver routine for IRP_MN_START_DEVICE requests.
    This routine kicks off any device specific initialization

Arguments:

    DeviceObject - a pointer to the device object

    Irp - a pointer to the io request packet

Return Value:

    none

--*/
NTSTATUS ClassPnpStartDevice(IN PDEVICE_OBJECT DeviceObject)
{
    PCLASS_DRIVER_EXTENSION driverExtension;
    PCLASS_INIT_DATA initData;

    PCLASS_DEV_INFO devInfo;

    PCOMMON_DEVICE_EXTENSION commonExtension = DeviceObject->DeviceExtension;
    PFUNCTIONAL_DEVICE_EXTENSION fdoExtension = DeviceObject->DeviceExtension;
    BOOLEAN isFdo = commonExtension->IsFdo;

    BOOLEAN isMountedDevice = TRUE;
    UNICODE_STRING  interfaceName;

    BOOLEAN timerStarted;

    NTSTATUS status = STATUS_SUCCESS;

    PAGED_CODE();

    driverExtension = IoGetDriverObjectExtension(DeviceObject->DriverObject,
                                                 CLASS_DRIVER_EXTENSION_KEY);

    initData = &(driverExtension->InitData);
    if(isFdo) {
        devInfo = &(initData->FdoData);
    } else {
        devInfo = &(initData->PdoData);
    }

    ASSERT(devInfo->ClassInitDevice != NULL);
    ASSERT(devInfo->ClassStartDevice != NULL);

    if (!commonExtension->IsInitialized){

        //
        // perform FDO/PDO specific initialization
        //

        if (isFdo){
            STORAGE_PROPERTY_ID propertyId;

            //
            // allocate a private extension for class data
            //

            if (fdoExtension->PrivateFdoData == NULL) {
                fdoExtension->PrivateFdoData =
                    ExAllocatePoolWithTag(NonPagedPool,
                                          sizeof(CLASS_PRIVATE_FDO_DATA),
                                          CLASS_TAG_PRIVATE_DATA
                                          );
            }

            if (fdoExtension->PrivateFdoData == NULL) {
                DebugPrint((0, "ClassPnpStartDevice: Cannot allocate for "
                            "private fdo data\n"));
                return STATUS_INSUFFICIENT_RESOURCES;
            }

            //
            // initialize the struct's various fields.
            //

            RtlZeroMemory(fdoExtension->PrivateFdoData,
                          sizeof(CLASS_PRIVATE_FDO_DATA)
                          );
            KeInitializeTimer(&fdoExtension->PrivateFdoData->Retry.Timer);
            KeInitializeDpc(&fdoExtension->PrivateFdoData->Retry.Dpc,
                            ClasspRetryRequestDpc,
                            DeviceObject);
            KeInitializeSpinLock(&fdoExtension->PrivateFdoData->Retry.Lock);
            fdoExtension->PrivateFdoData->Retry.Granularity =
                KeQueryTimeIncrement();
            commonExtension->Reserved4 = (ULONG_PTR)(' GPH'); // debug aid

            //
            // NOTE: the old interface allowed the class driver to allocate
            // this.  this was unsafe for low-memory conditions. allocate one
            // unconditionally now, and modify our internal functions to use
            // our own exclusively as it is the only safe way to do this.
            //

            status = ClasspAllocateReleaseQueueIrp(fdoExtension);
            if (!NT_SUCCESS(status)) {
                DebugPrint((0, "ClassPnpStartDevice: Cannot allocate the "
                            "private release queue irp\n"));
                return status;
            }

            //
            // Call port driver to get adapter capabilities.
            //

            propertyId = StorageAdapterProperty;

            status = ClassGetDescriptor(
                        commonExtension->LowerDeviceObject,
                        &propertyId,
                        &fdoExtension->AdapterDescriptor);

            if(!NT_SUCCESS(status)) {

                //
                // This DebugPrint is to help third-party driver writers
                //

                DebugPrint((0, "ClassPnpStartDevice: ClassGetDescriptor "
                               "[ADAPTER] failed %lx\n", status));
                return status;
            }

            //
            // Call port driver to get device descriptor.
            //

            propertyId = StorageDeviceProperty;

            status = ClassGetDescriptor(
                        commonExtension->LowerDeviceObject,
                        &propertyId,
                        &fdoExtension->DeviceDescriptor);

            if(!NT_SUCCESS(status)) {

                //
                // This DebugPrint is to help third-party driver writers
                //

                DebugPrint((0, "ClassPnpStartDevice: ClassGetDescriptor "
                               "[DEVICE] failed %lx\n", status));
                return status;
            }

            ClasspScanForSpecialInRegistry(fdoExtension);
            ClassScanForSpecial(fdoExtension,
                                ClassBadItems,
                                ClasspScanForClassHacks);

            //
            // allow perf to be re-enabled after a given number of failed IOs
            // require this number to be at least CLASS_PERF_RESTORE_MINIMUM
            //

            {
                ULONG t = 0;
                ClassGetDeviceParameter(fdoExtension,
                                        CLASSP_REG_SUBKEY_NAME,
                                        CLASSP_REG_PERF_RESTORE_VALUE_NAME,
                                        &t);
                if (t >= CLASS_PERF_RESTORE_MINIMUM) {
                    fdoExtension->PrivateFdoData->Perf.ReEnableThreshhold = t;
                }
            }


            //
            // compatibility comes first.  writable cd media will not
            // get a SYNCH_CACHE on power down.
            //

            if (fdoExtension->DeviceObject->DeviceType != FILE_DEVICE_DISK) {
                SET_FLAG(fdoExtension->PrivateFdoData->HackFlags,
                         FDO_HACK_NO_SYNC_CACHE);
            }

            //
            // initialize the hotplug information only after the ScanForSpecial
            // routines, as it relies upon the hack flags.
            //

            status = ClasspInitializeHotplugInfo(fdoExtension);

            if (!NT_SUCCESS(status)) {
                DebugPrint((1, "ClassPnpStartDevice: Could not initialize "
                            "hotplug information %lx\n", status));
                return status;
            }

            /*
             *  Allocate/initialize TRANSFER_PACKETs and related resources.
             */
            status = InitializeTransferPackets(DeviceObject);
        }

        //
        // ISSUE - drivers need to disable write caching on the media
        //         if hotplug and !useroverride.  perhaps we should
        //         allow registration of a callback to enable/disable
        //         write cache instead.
        //

        if (NT_SUCCESS(status)){
            status = devInfo->ClassInitDevice(DeviceObject);
        }

    }

    if (!NT_SUCCESS(status)){

        //
        // Just bail out - the remove that comes down will clean up the
        // initialized scraps.
        //

        return status;
    } else {
        commonExtension->IsInitialized = TRUE;

        if (commonExtension->IsFdo) {
            fdoExtension->PrivateFdoData->Perf.OriginalSrbFlags = fdoExtension->SrbFlags;
        }

    }

    //
    // If device requests autorun functionality or a once a second callback
    // then enable the once per second timer.
    //
    // NOTE: This assumes that ClassInitializeMediaChangeDetection is always
    //       called in the context of the ClassInitDevice callback. If called
    //       after then this check will have already been made and the
    //       once a second timer will not have been enabled.
    //
    if ((isFdo) &&
        ((initData-…

Large files files are truncated, but you can click here to view the full file