pnp.c File Reference

#include "disk.h"

Include dependency graph for pnp.c:

Go to the source code of this file.

Macros
#define	FDO_NAME_FORMAT   "\\Device\\Harddisk%d\\DR%d"

Functions
NTSTATUS NTAPI	DiskAddDevice (IN PDRIVER_OBJECT DriverObject, IN PDEVICE_OBJECT PhysicalDeviceObject)
NTSTATUS NTAPI	DiskInitFdo (IN PDEVICE_OBJECT Fdo)
NTSTATUS NTAPI	DiskStopDevice (IN PDEVICE_OBJECT DeviceObject, IN UCHAR Type)
NTSTATUS	DiskGenerateDeviceName (IN ULONG DeviceNumber, OUT PCCHAR *RawName)
VOID	DiskCreateSymbolicLinks (IN PDEVICE_OBJECT DeviceObject)
VOID	DiskDeleteSymbolicLinks (IN PDEVICE_OBJECT DeviceObject)
NTSTATUS NTAPI	DiskRemoveDevice (IN PDEVICE_OBJECT DeviceObject, IN UCHAR Type)
NTSTATUS NTAPI	DiskStartFdo (IN PDEVICE_OBJECT Fdo)

Variables
PULONG	InitSafeBootMode
ULONG	diskDeviceSequenceNumber = 0
BOOLEAN	DiskIsPastReinit

Macro Definition Documentation

FDO_NAME_FORMAT

#define FDO_NAME_FORMAT   "\\Device\\Harddisk%d\\DR%d"

Function Documentation

DiskAddDevice()

NTSTATUS NTAPI DiskAddDevice	(	IN PDRIVER_OBJECT	DriverObject,
		IN PDEVICE_OBJECT	PhysicalDeviceObject
	)

Definition at line 53 of file pnp.c.

{
    ULONG rootPartitionMountable = FALSE;

    PCONFIGURATION_INFORMATION configurationInformation;
    ULONG diskCount;

    NTSTATUS status;

    PAGED_CODE();

    //
    // See if we should be allowing file systems to mount on partition zero.
    //

    TRY {
        HANDLE deviceKey = NULL;

        UNICODE_STRING diskKeyName;
        OBJECT_ATTRIBUTES objectAttributes = {0};
        HANDLE diskKey;

        RTL_QUERY_REGISTRY_TABLE queryTable[2] = { 0 };

        status = IoOpenDeviceRegistryKey(PhysicalDeviceObject,
                                         PLUGPLAY_REGKEY_DEVICE,
                                         KEY_READ,
                                         &deviceKey);

        if(!NT_SUCCESS(status)) {
            TracePrint((TRACE_LEVEL_ERROR, TRACE_FLAG_PNP, "DiskAddDevice: Error %#08lx opening device key "
                           "for pdo %p\n",
                        status, PhysicalDeviceObject));
            LEAVE;
        }

        RtlInitUnicodeString(&diskKeyName, L"Disk");
        InitializeObjectAttributes(&objectAttributes,
                                   &diskKeyName,
                                   OBJ_CASE_INSENSITIVE | OBJ_KERNEL_HANDLE,
                                   deviceKey,
                                   NULL);

        status = ZwOpenKey(&diskKey, KEY_READ, &objectAttributes);
        ZwClose(deviceKey);

        if(!NT_SUCCESS(status)) {
            TracePrint((TRACE_LEVEL_ERROR, TRACE_FLAG_PNP, "DiskAddDevice: Error %#08lx opening disk key "
                           "for pdo %p device key %p\n",
                        status, PhysicalDeviceObject, deviceKey));
            LEAVE;
        }

        queryTable[0].Flags = RTL_QUERY_REGISTRY_DIRECT | RTL_QUERY_REGISTRY_TYPECHECK;
        queryTable[0].Name = L"RootPartitionMountable";
        queryTable[0].EntryContext = &(rootPartitionMountable);
        queryTable[0].DefaultType = (REG_DWORD << RTL_QUERY_REGISTRY_TYPECHECK_SHIFT) | REG_NONE;

#ifdef _MSC_VER
#pragma prefast(suppress:6309, "We don't have QueryRoutine so Context doesn't make any sense")
#endif
        status = RtlQueryRegistryValues(RTL_REGISTRY_HANDLE,
                                        diskKey,
                                        queryTable,
                                        NULL,
                                        NULL);

        if(!NT_SUCCESS(status)) {
            TracePrint((TRACE_LEVEL_ERROR, TRACE_FLAG_PNP, "DiskAddDevice: Error %#08lx reading value from "
                           "disk key %p for pdo %p\n",
                        status, diskKey, PhysicalDeviceObject));
        }

        ZwClose(diskKey);

    } FINALLY {

        //
        // Do nothing.
        //

        if(!NT_SUCCESS(status)) {
            TracePrint((TRACE_LEVEL_WARNING, TRACE_FLAG_PNP, "DiskAddDevice: Will %sallow file system to mount on "
                           "partition zero of disk %p\n",
                        (rootPartitionMountable ? "" : "not "),
                        PhysicalDeviceObject));
        }
    }

    //
    // Create device objects for disk
    //

    diskCount = 0;

    status = DiskCreateFdo(
                 DriverObject,
                 PhysicalDeviceObject,
                 &diskCount,
                 (BOOLEAN) !rootPartitionMountable
                 );

    //
    // Get the number of disks already initialized.
    //

    configurationInformation = IoGetConfigurationInformation();

    if (NT_SUCCESS(status)) {

        //
        // Increment system disk device count.
        //

        configurationInformation->DiskCount++;

    }

    return status;

} // end DiskAddDevice()

Referenced by DriverEntry().

DiskCreateSymbolicLinks()

VOID DiskCreateSymbolicLinks

(

IN PDEVICE_OBJECT

DeviceObject

)

Definition at line 676 of file pnp.c.

{
    PCOMMON_DEVICE_EXTENSION commonExtension = DeviceObject->DeviceExtension;
    PDISK_DATA diskData = commonExtension->DriverData;

    WCHAR wideSourceName[64] = { 0 };
    UNICODE_STRING unicodeSourceName;

    NTSTATUS status;

    PAGED_CODE();

    //
    // Build the destination for the link first using the device name
    // stored in the device object
    //

    NT_ASSERT(commonExtension->DeviceName.Buffer);

    if(!diskData->LinkStatus.WellKnownNameCreated) {
        //
        // Put together the source name using the partition and device number
        // in the device extension and disk data segment
        //

        status = RtlStringCchPrintfW(wideSourceName, sizeof(wideSourceName) / sizeof(wideSourceName[0]) - 1,
                                     L"\\Device\\Harddisk%d\\Partition0",
                                     commonExtension->PartitionZeroExtension->DeviceNumber);

        if (NT_SUCCESS(status)) {

            RtlInitUnicodeString(&unicodeSourceName, wideSourceName);

            TracePrint((TRACE_LEVEL_INFORMATION, TRACE_FLAG_PNP, "DiskCreateSymbolicLink: Linking %wZ to %wZ\n",
                       &unicodeSourceName,
                       &commonExtension->DeviceName));

            status = IoCreateSymbolicLink(&unicodeSourceName,
                                          &commonExtension->DeviceName);

            if(NT_SUCCESS(status)){
                diskData->LinkStatus.WellKnownNameCreated = TRUE;
            }
        }
    }

    if (!diskData->LinkStatus.PhysicalDriveLinkCreated) {

        //
        // Create a physical drive N link using the device number we saved
        // away during AddDevice.
        //

        status = RtlStringCchPrintfW(wideSourceName, sizeof(wideSourceName) / sizeof(wideSourceName[0]) - 1,
                                     L"\\DosDevices\\PhysicalDrive%d",
                                     commonExtension->PartitionZeroExtension->DeviceNumber);
        if (NT_SUCCESS(status)) {

            RtlInitUnicodeString(&unicodeSourceName, wideSourceName);

            TracePrint((TRACE_LEVEL_INFORMATION, TRACE_FLAG_PNP, "DiskCreateSymbolicLink: Linking %wZ to %wZ\n",
                        &unicodeSourceName,
                        &(commonExtension->DeviceName)));

            status = IoCreateSymbolicLink(&unicodeSourceName,
                                          &(commonExtension->DeviceName));

            if(NT_SUCCESS(status)) {
                diskData->LinkStatus.PhysicalDriveLinkCreated = TRUE;
            }
        }
    }


    return;
}

Referenced by DiskInitFdo().

DiskDeleteSymbolicLinks()

VOID DiskDeleteSymbolicLinks

(

IN PDEVICE_OBJECT

DeviceObject

)

Definition at line 780 of file pnp.c.

{
    PCOMMON_DEVICE_EXTENSION commonExtension = DeviceObject->DeviceExtension;
    PDISK_DATA diskData = commonExtension->DriverData;

    WCHAR wideLinkName[64] = { 0 };
    UNICODE_STRING unicodeLinkName;
    NTSTATUS status;

    PAGED_CODE();

    if(diskData->LinkStatus.WellKnownNameCreated) {

        status = RtlStringCchPrintfW(wideLinkName, sizeof(wideLinkName) / sizeof(wideLinkName[0]) - 1,
                                    L"\\Device\\Harddisk%d\\Partition0",
                                    commonExtension->PartitionZeroExtension->DeviceNumber);
        if (NT_SUCCESS(status)) {
            RtlInitUnicodeString(&unicodeLinkName, wideLinkName);
            IoDeleteSymbolicLink(&unicodeLinkName);
        }
        diskData->LinkStatus.WellKnownNameCreated = FALSE;
    }

    if(diskData->LinkStatus.PhysicalDriveLinkCreated) {

        status = RtlStringCchPrintfW(wideLinkName, sizeof(wideLinkName) / sizeof(wideLinkName[0]) - 1,
                                    L"\\DosDevices\\PhysicalDrive%d",
                                    commonExtension->PartitionZeroExtension->DeviceNumber);
        if (NT_SUCCESS(status)) {
            RtlInitUnicodeString(&unicodeLinkName, wideLinkName);
            IoDeleteSymbolicLink(&unicodeLinkName);
        }
        diskData->LinkStatus.PhysicalDriveLinkCreated = FALSE;
    }


    return;
}

Referenced by DiskRemoveDevice().

DiskGenerateDeviceName()

NTSTATUS DiskGenerateDeviceName	(	IN ULONG	DeviceNumber,
		OUT PCCHAR *	RawName
	)

Definition at line 612 of file pnp.c.

{
    CHAR rawName[64] = { 0 };
    NTSTATUS status;

    PAGED_CODE();

        status = RtlStringCchPrintfA(rawName, sizeof(rawName) - 1, FDO_NAME_FORMAT, DeviceNumber,
                                    diskDeviceSequenceNumber++);
        if (!NT_SUCCESS(status)) {
            TracePrint((TRACE_LEVEL_ERROR, TRACE_FLAG_PNP, "DiskGenerateDeviceName: Format FDO name failed with error: 0x%X\n", status));
            return status;
        }

    *RawName = ExAllocatePoolWithTag(PagedPool,
                                     strlen(rawName) + 1,
                                     DISK_TAG_NAME);

    if(*RawName == NULL) {
        return STATUS_INSUFFICIENT_RESOURCES;
    }

    status = RtlStringCchCopyA(*RawName, strlen(rawName) + 1, rawName);
    if (!NT_SUCCESS(status)) {
        TracePrint((TRACE_LEVEL_ERROR, TRACE_FLAG_PNP, "DiskGenerateDeviceName: Device name copy failed with error: 0x%X\n", status));
        FREE_POOL(*RawName);
        return status;
    }

    TracePrint((TRACE_LEVEL_INFORMATION, TRACE_FLAG_PNP, "DiskGenerateDeviceName: generated \"%s\"\n", rawName));

    return STATUS_SUCCESS;
}

Referenced by DiskCreateFdo().

DiskInitFdo()

NTSTATUS NTAPI DiskInitFdo

(

IN PDEVICE_OBJECT

Fdo

)

Definition at line 202 of file pnp.c.

{
    PFUNCTIONAL_DEVICE_EXTENSION fdoExtension = Fdo->DeviceExtension;
    PDISK_DATA diskData = (PDISK_DATA) fdoExtension->CommonExtension.DriverData;

    ULONG srbFlags = 0;
    ULONG timeOut = 0;
    ULONG bytesPerSector;

    PULONG dmSkew;

    NTSTATUS status = STATUS_SUCCESS;

    PAGED_CODE();

    //
    // Build the lookaside list for srb's for the physical disk. Should only
    // need a couple.  If this fails then we don't have an emergency SRB so
    // fail the call to initialize.
    //

    ClassInitializeSrbLookasideList((PCOMMON_DEVICE_EXTENSION) fdoExtension,
                                    PARTITION0_LIST_SIZE);

    if (fdoExtension->DeviceDescriptor->RemovableMedia)
    {
        SET_FLAG(Fdo->Characteristics, FILE_REMOVABLE_MEDIA);
    }

    //
    // Initialize the srb flags.
    //

    //
    // Because all requests share a common sense buffer, it is possible
    // for the buffer to be overwritten if the port driver completes
    // multiple failed requests that require a request sense before the
    // class driver's completion routine can consume the data in the buffer.
    // To prevent this, we allow the port driver to allocate a unique sense
    // buffer each time it needs one.  We are responsible for freeing this
    // buffer.  This also allows the adapter to be configured to support
    // additional sense data beyond the minimum 18 bytes.
    //

    SET_FLAG(fdoExtension->SrbFlags, SRB_FLAGS_PORT_DRIVER_ALLOCSENSE);

    if (fdoExtension->DeviceDescriptor->CommandQueueing &&
        fdoExtension->AdapterDescriptor->CommandQueueing) {

        SET_FLAG(fdoExtension->SrbFlags, SRB_FLAGS_QUEUE_ACTION_ENABLE);

    }

    //
    // Look for controllers that require special flags.
    //

    ClassScanForSpecial(fdoExtension, DiskBadControllers, DiskSetSpecialHacks);

    //
    // Clear buffer for drive geometry.
    //

    RtlZeroMemory(&(fdoExtension->DiskGeometry),
                  sizeof(DISK_GEOMETRY));

    //
    // Allocate request sense buffer.
    //

    fdoExtension->SenseData = ExAllocatePoolWithTag(NonPagedPoolNxCacheAligned,
                                                    SENSE_BUFFER_SIZE_EX,
                                                    DISK_TAG_START);

    if (fdoExtension->SenseData == NULL) {

        //
        // The buffer can not be allocated.
        //

        TracePrint((TRACE_LEVEL_ERROR, TRACE_FLAG_PNP, "DiskInitFdo: Can not allocate request sense buffer\n"));

        status = STATUS_INSUFFICIENT_RESOURCES;
        return status;
    }

    //
    // Set the buffer size of SenseData
    //

    fdoExtension->SenseDataLength = SENSE_BUFFER_SIZE_EX;

    //
    // Physical device object will describe the entire
    // device, starting at byte offset 0.
    //

    fdoExtension->CommonExtension.StartingOffset.QuadPart = (LONGLONG)(0);

    //
    // Set timeout value in seconds.
    //
    if ( (fdoExtension->MiniportDescriptor != NULL) &&
         (fdoExtension->MiniportDescriptor->IoTimeoutValue > 0) ) {
        //
        // use the value set by Storport miniport driver
        //
        fdoExtension->TimeOutValue = fdoExtension->MiniportDescriptor->IoTimeoutValue;
    } else {
        //
        // get timeout value from registry
        //
        timeOut = ClassQueryTimeOutRegistryValue(Fdo);

        if (timeOut) {
            fdoExtension->TimeOutValue = timeOut;
        } else {
            fdoExtension->TimeOutValue = SCSI_DISK_TIMEOUT;
        }
    }
    //
    // If this is a removable drive, build an entry in devicemap\scsi
    // indicating it's physicaldriveN name, set up the appropriate
    // update partitions routine and set the flags correctly.
    // note: only do this after the timeout value is set, above.
    //

    if (TEST_FLAG(Fdo->Characteristics, FILE_REMOVABLE_MEDIA)) {

        ClassUpdateInformationInRegistry( Fdo,
                                          "PhysicalDrive",
                                          fdoExtension->DeviceNumber,
                                          NULL,
                                          0);
        //
        // Enable media change notification for removable disks
        //
        ClassInitializeMediaChangeDetection(fdoExtension,
                                            (PUCHAR)"Disk");

    } else {

        SET_FLAG(fdoExtension->DeviceFlags, DEV_SAFE_START_UNIT);
        SET_FLAG(fdoExtension->SrbFlags, SRB_FLAGS_NO_QUEUE_FREEZE);

    }

    //
    // The commands we send during the init could cause the flags to change
    // in case of any error.  Save the SRB flags locally and restore it at
    // the end of this function, so that the class driver can get it.
    //

    srbFlags = fdoExtension->SrbFlags;


    //
    // Read the drive capacity.  Don't use the disk version of the routine here
    // since we don't know the disk signature yet - the disk version will
    // attempt to determine the BIOS reported geometry.
    //

    (VOID)ClassReadDriveCapacity(Fdo);

    //
    // Set up sector size fields.
    //
    // Stack variables will be used to update
    // the partition device extensions.
    //
    // The device extension field SectorShift is
    // used to calculate sectors in I/O transfers.
    //
    // The DiskGeometry structure is used to service
    // IOCTls used by the format utility.
    //

    bytesPerSector = fdoExtension->DiskGeometry.BytesPerSector;

    //
    // Make sure sector size is not zero.
    //

    if (bytesPerSector == 0) {

        //
        // Default sector size for disk is 512.
        //

        bytesPerSector = fdoExtension->DiskGeometry.BytesPerSector = 512;
        fdoExtension->SectorShift = 9;
    }

    //
    // Determine is DM Driver is loaded on an IDE drive that is
    // under control of Atapi - this could be either a crashdump or
    // an Atapi device is sharing the controller with an IDE disk.
    //

    HalExamineMBR(fdoExtension->CommonExtension.DeviceObject,
                  fdoExtension->DiskGeometry.BytesPerSector,
                  (ULONG)0x54,
                  (PVOID *)&dmSkew);

    if (dmSkew) {

        //
        // Update the device extension, so that the call to IoReadPartitionTable
        // will get the correct information. Any I/O to this disk will have
        // to be skewed by *dmSkew sectors aka DMByteSkew.
        //

        fdoExtension->DMSkew     = *dmSkew;
        fdoExtension->DMActive   = TRUE;
        fdoExtension->DMByteSkew = fdoExtension->DMSkew * bytesPerSector;

        FREE_POOL(dmSkew);
    }

#if defined(_X86_) || defined(_AMD64_)

    //
    // Try to read the signature off the disk and determine the correct drive
    // geometry based on that.  This requires rereading the disk size to get
    // the cylinder count updated correctly.
    //

    if(!TEST_FLAG(Fdo->Characteristics, FILE_REMOVABLE_MEDIA)) {

        DiskReadSignature(Fdo);
        DiskReadDriveCapacity(Fdo);

        if (diskData->GeometrySource == DiskGeometryUnknown)
        {
            //
            // Neither the  BIOS  nor the port driver could provide us with a  reliable
            // geometry.  Before we use the default,  look to see if it was partitioned
            // under Windows NT4 [or earlier] and apply the one that was used back then
            //

            if (DiskIsNT4Geometry(fdoExtension))
            {
                diskData->RealGeometry = fdoExtension->DiskGeometry;
                diskData->RealGeometry.SectorsPerTrack   = 0x20;
                diskData->RealGeometry.TracksPerCylinder = 0x40;
                fdoExtension->DiskGeometry = diskData->RealGeometry;

                diskData->GeometrySource = DiskGeometryFromNT4;
            }
        }
    }

#endif

    DiskCreateSymbolicLinks(Fdo);

    //
    // Get the SCSI address if it's available for use with SMART ioctls.
    // SMART ioctls are used for failure prediction, so we need to get
    // the SCSI address before initializing failure prediction.
    //

    {
        PIRP irp;
        KEVENT event;
        IO_STATUS_BLOCK statusBlock = { 0 };

        KeInitializeEvent(&event, SynchronizationEvent, FALSE);

        irp = IoBuildDeviceIoControlRequest(IOCTL_SCSI_GET_ADDRESS,
                                            fdoExtension->CommonExtension.LowerDeviceObject,
                                            NULL,
                                            0L,
                                            &(diskData->ScsiAddress),
                                            sizeof(SCSI_ADDRESS),
                                            FALSE,
                                            &event,
                                            &statusBlock);

        status = STATUS_UNSUCCESSFUL;

        if(irp != NULL) {

            status = IoCallDriver(fdoExtension->CommonExtension.LowerDeviceObject, irp);

            if(status == STATUS_PENDING) {
                KeWaitForSingleObject(&event,
                                      Executive,
                                      KernelMode,
                                      FALSE,
                                      NULL);
                status = statusBlock.Status;
            }
        }
    }

    //
    // Determine the type of disk and enable failure prediction in the hardware
    // and enable failure prediction polling.
    //

    if (InitSafeBootMode == 0) // __REACTOS__
    {
        DiskDetectFailurePrediction(fdoExtension,
                                    &diskData->FailurePredictionCapability,
                                    NT_SUCCESS(status));

        if (diskData->FailurePredictionCapability != FailurePredictionNone)
        {
            //
            // Cool, we've got some sort of failure prediction, enable it
            // at the hardware and then enable polling for it
            //

            //
            // By default we allow performance to be degradeded if failure
            // prediction is enabled.
            //

            diskData->AllowFPPerfHit = TRUE;

            //
            // Enable polling only after Atapi and SBP2 add support for the new
            // SRB flag that indicates that the request should not reset the
            // drive spin down idle timer.
            //

            status = DiskEnableDisableFailurePredictPolling(fdoExtension,
                                          TRUE,
                                          DISK_DEFAULT_FAILURE_POLLING_PERIOD);

            TracePrint((TRACE_LEVEL_INFORMATION, TRACE_FLAG_PNP, "DiskInitFdo: Failure Prediction Poll enabled as "
                           "%d for device %p, Status = %lx\n",
                     diskData->FailurePredictionCapability,
                     Fdo,
                     status));
        }
    } else {

        //
        // In safe boot mode we do not enable failure prediction, as perhaps
        // it is the reason why normal boot does not work
        //

        diskData->FailurePredictionCapability = FailurePredictionNone;

    }

    //
    // Initialize the verify mutex
    //

    KeInitializeMutex(&diskData->VerifyMutex, MAX_SECTORS_PER_VERIFY);

    //
    // Initialize the flush group context
    //

    RtlZeroMemory(&diskData->FlushContext, sizeof(DISK_GROUP_CONTEXT));

    InitializeListHead(&diskData->FlushContext.CurrList);
    InitializeListHead(&diskData->FlushContext.NextList);

    KeInitializeSpinLock(&diskData->FlushContext.Spinlock);
    KeInitializeEvent(&diskData->FlushContext.Event, SynchronizationEvent, FALSE);


    //
    // Restore the saved value
    //
    fdoExtension->SrbFlags = srbFlags;

    return STATUS_SUCCESS;

} // end DiskInitFdo()

Referenced by DriverEntry().

DiskRemoveDevice()

NTSTATUS NTAPI DiskRemoveDevice	(	IN PDEVICE_OBJECT	DeviceObject,
		IN UCHAR	Type
	)

Definition at line 843 of file pnp.c.

{
    PCOMMON_DEVICE_EXTENSION commonExtension = DeviceObject->DeviceExtension;
    PFUNCTIONAL_DEVICE_EXTENSION fdoExtension = DeviceObject->DeviceExtension;

    PAGED_CODE();

    //
    // Handle query and cancel
    //

    if((Type == IRP_MN_QUERY_REMOVE_DEVICE) ||
       (Type == IRP_MN_CANCEL_REMOVE_DEVICE)) {
        return STATUS_SUCCESS;
    }

    //
    // Delete our object directory.
    //

    if(fdoExtension->DeviceDirectory != NULL) {
        ZwMakeTemporaryObject(fdoExtension->DeviceDirectory);
        ZwClose(fdoExtension->DeviceDirectory);
        fdoExtension->DeviceDirectory = NULL;
    }

    if(Type == IRP_MN_REMOVE_DEVICE) {

        FREE_POOL(fdoExtension->SenseData);

        IoGetConfigurationInformation()->DiskCount--;

    }

    DiskDeleteSymbolicLinks(DeviceObject);

    if (Type == IRP_MN_REMOVE_DEVICE)
    {
        ClassDeleteSrbLookasideList(commonExtension);
    }

    return STATUS_SUCCESS;
}

Referenced by DriverEntry().

DiskStartFdo()

NTSTATUS NTAPI DiskStartFdo

(

IN PDEVICE_OBJECT

Fdo

)

Definition at line 911 of file pnp.c.

{
    PFUNCTIONAL_DEVICE_EXTENSION fdoExtension = Fdo->DeviceExtension;
    PCOMMON_DEVICE_EXTENSION commonExtension = &(fdoExtension->CommonExtension);
    PDISK_DATA diskData = commonExtension->DriverData;
    STORAGE_HOTPLUG_INFO hotplugInfo = { 0 };
    DISK_CACHE_INFORMATION cacheInfo = { 0 };
    ULONG isPowerProtected = 0;
    NTSTATUS status;

    PAGED_CODE();

    //
    // Get the hotplug information, so we can turn off write cache if needed
    //
    // NOTE: Capabilities info is not good enough to determine hotplugedness
    //       as  we cannot determine device relations  information and other
    //       dependencies. Get the hotplug info instead
    //

    {
        PIRP irp;
        KEVENT event;
        IO_STATUS_BLOCK statusBlock = { 0 };

        KeInitializeEvent(&event, SynchronizationEvent, FALSE);

        irp = IoBuildDeviceIoControlRequest(IOCTL_STORAGE_GET_HOTPLUG_INFO,
                                            Fdo,
                                            NULL,
                                            0L,
                                            &hotplugInfo,
                                            sizeof(STORAGE_HOTPLUG_INFO),
                                            FALSE,
                                            &event,
                                            &statusBlock);

        if (irp != NULL) {

            // send to self -- classpnp handles this
            status = IoCallDriver(Fdo, irp);
            if (status == STATUS_PENDING) {
                KeWaitForSingleObject(&event,
                                      Executive,
                                      KernelMode,
                                      FALSE,
                                      NULL);

                status = statusBlock.Status;
            }
            NT_ASSERT(NT_SUCCESS(status));
        }
    }

    //
    // Clear the DEV_WRITE_CACHE flag now  and set
    // it below only if we read that from the disk
    //
    CLEAR_FLAG(fdoExtension->DeviceFlags, DEV_WRITE_CACHE);
    ADJUST_FUA_FLAG(fdoExtension);

    diskData->WriteCacheOverride = DiskWriteCacheDefault;

    //
    // Look into the registry to  see if the user
    // has chosen to override the default setting
    //
    ClassGetDeviceParameter(fdoExtension,
                            DiskDeviceParameterSubkey,
                            DiskDeviceUserWriteCacheSetting,
                            (PULONG)&diskData->WriteCacheOverride);

    if (diskData->WriteCacheOverride == DiskWriteCacheDefault)
    {
        //
        // The user has not overridden the default settings
        //
        if (TEST_FLAG(fdoExtension->ScanForSpecialFlags, CLASS_SPECIAL_DISABLE_WRITE_CACHE))
        {
            //
            // This flag indicates that we have faulty firmware and this
            // may cause the filesystem to refuse to mount on this media
            //
            TracePrint((TRACE_LEVEL_WARNING, TRACE_FLAG_PNP, "DiskStartFdo: Turning off write cache for %p due to a firmware issue\n", Fdo));

            diskData->WriteCacheOverride = DiskWriteCacheDisable;
        }
        else if (hotplugInfo.DeviceHotplug && !hotplugInfo.WriteCacheEnableOverride)
        {
            //
            // This flag indicates that the device is hotpluggable making it unsafe to enable caching
            //
            TracePrint((TRACE_LEVEL_WARNING, TRACE_FLAG_PNP, "DiskStartFdo: Turning off write cache for %p due to hotpluggable device\n", Fdo));

            diskData->WriteCacheOverride = DiskWriteCacheDisable;
        }
        else if (hotplugInfo.MediaHotplug)
        {
            //
            // This flag indicates that the media in the device cannot be reliably locked
            //
            TracePrint((TRACE_LEVEL_WARNING, TRACE_FLAG_PNP, "DiskStartFdo: Turning off write cache for %p due to unlockable media\n", Fdo));

            diskData->WriteCacheOverride = DiskWriteCacheDisable;
        }
        else
        {
            //
            // Even though the device does  not seem to have any obvious problems
            // we leave it to the user to modify the previous write cache setting
            //
        }
    }

    //
    // Query the disk to see if write cache is enabled
    // and  set the DEV_WRITE_CACHE flag appropriately
    //

    status = DiskGetCacheInformation(fdoExtension, &cacheInfo);

    if (NT_SUCCESS(status))
    {
        if (cacheInfo.WriteCacheEnabled == TRUE)
        {
            SET_FLAG(fdoExtension->DeviceFlags, DEV_WRITE_CACHE);
            ADJUST_FUA_FLAG(fdoExtension);

            if (diskData->WriteCacheOverride == DiskWriteCacheDisable)
            {
                //
                // Write cache is currently enabled on this
                // device, but we would like to turn it off
                //
                cacheInfo.WriteCacheEnabled = FALSE;

                DiskSetCacheInformation(fdoExtension, &cacheInfo);
            }
        }
        else
        {
            if (diskData->WriteCacheOverride == DiskWriteCacheEnable)
            {
                //
                // Write cache is currently disabled on this
                // device, but we  would  like to turn it on
                //
                cacheInfo.WriteCacheEnabled = TRUE;

                DiskSetCacheInformation(fdoExtension, &cacheInfo);
            }
        }
    }

    //
    // Query the registry to see if this disk is power-protected or not
    //

    CLEAR_FLAG(fdoExtension->DeviceFlags, DEV_POWER_PROTECTED);

    ClassGetDeviceParameter(fdoExtension, DiskDeviceParameterSubkey, DiskDeviceCacheIsPowerProtected, &isPowerProtected);

    if (isPowerProtected == 1)
    {
        SET_FLAG(fdoExtension->DeviceFlags, DEV_POWER_PROTECTED);
    }

    ADJUST_FUA_FLAG(fdoExtension);

    return STATUS_SUCCESS;

} // end DiskStartFdo()

Referenced by DriverEntry().

DiskStopDevice()

NTSTATUS NTAPI DiskStopDevice	(	IN PDEVICE_OBJECT	DeviceObject,
		IN UCHAR	Type
	)

Definition at line 600 of file pnp.c.

{
    UNREFERENCED_PARAMETER(DeviceObject);
    UNREFERENCED_PARAMETER(Type);
    return STATUS_SUCCESS;
}

Referenced by DriverEntry().

Variable Documentation

diskDeviceSequenceNumber

ULONG diskDeviceSequenceNumber = 0

Definition at line 35 of file pnp.c.

Referenced by DiskGenerateDeviceName().

DiskIsPastReinit

BOOLEAN DiskIsPastReinit

Definition at line 81 of file disk.c.

Referenced by DiskDriverReinit().

InitSafeBootMode

PULONG InitSafeBootMode

Definition at line 71 of file init.c.

Referenced by DiskInitFdo().