classp.h

This is the library for all storage drivers. It simplifies writing a storage driver by implementing

     */
    SCSI_REQUEST_BLOCK SrbTemplate;

    KSPIN_LOCK SpinLock;

    /*
     *  For non-removable media, we read the drive capacity at start time and cache it.
     *  This is so that ReadDriveCapacity failures at runtime (e.g. due to memory stress)
     *  don't cause I/O on the paging disk to start failing.
     */
    READ_CAPACITY_DATA_EX LastKnownDriveCapacityData;
    BOOLEAN IsCachedDriveCapDataValid;

    /*
     *  Circular array of timestamped logs of errors that occurred on this device.
     */
    ULONG ErrorLogNextIndex;
    CLASS_ERROR_LOG_DATA ErrorLogs[NUM_ERROR_LOG_ENTRIES];

    //
    // Number of outstanding critical Io requests from Mm
    //
    ULONG NumHighPriorityPagingIo;

    //
    // Maximum number of normal Io requests that can be interleaved with the critical ones
    //
    ULONG MaxInterleavedNormalIo;

    //
    // The timestamp when entering throttle mode
    //
    LARGE_INTEGER ThrottleStartTime;

    //
    // The timestamp when exiting throttle mode
    //
    LARGE_INTEGER ThrottleStopTime;

    //
    // The longest time ever spent in throttle mode
    //
    LARGE_INTEGER LongestThrottlePeriod;

    #if DBG
        ULONG DbgMaxPktId;

        /*
         *  Logging fields for ForceUnitAccess and Flush
         */
        BOOLEAN DbgInitFlushLogging;         // must reset this to 1 for each logging session
        ULONG DbgNumIORequests;
        ULONG DbgNumFUAs;       // num I/O requests with ForceUnitAccess bit set
        ULONG DbgNumFlushes;    // num SRB_FUNCTION_FLUSH_QUEUE
        ULONG DbgIOsSinceFUA;
        ULONG DbgIOsSinceFlush;
        ULONG DbgAveIOsToFUA;      // average number of I/O requests between FUAs
        ULONG DbgAveIOsToFlush;   // ...
        ULONG DbgMaxIOsToFUA;
        ULONG DbgMaxIOsToFlush;
        ULONG DbgMinIOsToFUA;
        ULONG DbgMinIOsToFlush;

        /*
         *  Debug log of previously sent packets (including retries).
         */
        ULONG DbgPacketLogNextIndex;
        TRANSFER_PACKET DbgPacketLogs[DBG_NUM_PACKET_LOG_ENTRIES];
    #endif

};


#define MIN(a, b)   ((a) < (b) ? (a) : (b))
#define MAX(a, b)   ((a) > (b) ? (a) : (b))


#define NOT_READY_RETRY_INTERVAL    10
#define MINIMUM_RETRY_UNITS ((LONGLONG)32)


/*
 *  Simple singly-linked-list queuing macros, with no synchronization.
 */
__inline VOID SimpleInitSlistHdr(SINGLE_LIST_ENTRY *SListHdr)
{
    SListHdr->Next = NULL;
}
__inline VOID SimplePushSlist(SINGLE_LIST_ENTRY *SListHdr, SINGLE_LIST_ENTRY *SListEntry)
{
    SListEntry->Next = SListHdr->Next;
    SListHdr->Next = SListEntry;
}
__inline SINGLE_LIST_ENTRY *SimplePopSlist(SINGLE_LIST_ENTRY *SListHdr)
{
    SINGLE_LIST_ENTRY *sListEntry = SListHdr->Next;
    if (sListEntry){
        SListHdr->Next = sListEntry->Next;
        sListEntry->Next = NULL;
    }
    return sListEntry;
}
__inline BOOLEAN SimpleIsSlistEmpty(SINGLE_LIST_ENTRY *SListHdr)
{
    return (SListHdr->Next == NULL);
}

NTSTATUS
DriverEntry(
    IN PDRIVER_OBJECT DriverObject,
    IN PUNICODE_STRING RegistryPath
    );

VOID
ClassUnload(
    IN PDRIVER_OBJECT DriverObject
    );

NTSTATUS
ClassCreateClose(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    );

NTSTATUS
ClasspCreateClose(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    );

VOID
ClasspCleanupProtectedLocks(
    IN PFILE_OBJECT_EXTENSION FsContext
    );

NTSTATUS
ClasspEjectionControl(
    IN PDEVICE_OBJECT Fdo,
    IN PIRP Irp,
    IN MEDIA_LOCK_TYPE LockType,
    IN BOOLEAN Lock
    );

NTSTATUS
ClassReadWrite(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    );

NTSTATUS
ClassDeviceControlDispatch(
    PDEVICE_OBJECT DeviceObject,
    PIRP Irp
    );

NTSTATUS
ClassDeviceControl(
    PDEVICE_OBJECT DeviceObject,
    PIRP Irp
    );

NTSTATUS
ClassDispatchPnp(
    PDEVICE_OBJECT DeviceObject,
    PIRP Irp
    );

NTSTATUS
ClassPnpStartDevice(
    IN PDEVICE_OBJECT DeviceObject
    );

NTSTATUS
ClassInternalIoControl (
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    );

NTSTATUS
ClassShutdownFlush(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    );

NTSTATUS
ClassSystemControl(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    );

//
// Class internal routines
//

NTSTATUS
ClassAddDevice(
    IN PDRIVER_OBJECT DriverObject,
    IN OUT PDEVICE_OBJECT PhysicalDeviceObject
    );

NTSTATUS
ClasspSendSynchronousCompletion(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp,
    IN PVOID Context
    );

VOID
RetryRequest(
    PDEVICE_OBJECT DeviceObject,
    PIRP Irp,
    PSCSI_REQUEST_BLOCK Srb,
    BOOLEAN Associated,
    ULONG RetryInterval
    );

NTSTATUS
ClassIoCompletion(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp,
    IN PVOID Context
    );

NTSTATUS
ClassPnpQueryFdoRelations(
    IN PDEVICE_OBJECT Fdo,
    IN PIRP Irp
    );

NTSTATUS
ClassRetrieveDeviceRelations(
    IN PDEVICE_OBJECT Fdo,
    IN DEVICE_RELATION_TYPE RelationType,
    OUT PDEVICE_RELATIONS *DeviceRelations
    );

NTSTATUS
ClassGetPdoId(
    IN PDEVICE_OBJECT Pdo,
    IN BUS_QUERY_ID_TYPE IdType,
    IN PUNICODE_STRING IdString
    );

NTSTATUS
ClassQueryPnpCapabilities(
    IN PDEVICE_OBJECT PhysicalDeviceObject,
    IN PDEVICE_CAPABILITIES Capabilities
    );

VOID
ClasspStartIo(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    );

NTSTATUS
ClasspPagingNotificationCompletion(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp,
    IN PDEVICE_OBJECT RealDeviceObject
    );

NTSTATUS
ClasspMediaChangeCompletion(
    PDEVICE_OBJECT DeviceObject,
    PIRP Irp,
    PVOID Context
    );

PFILE_OBJECT_EXTENSION
ClasspGetFsContext(
    IN PCOMMON_DEVICE_EXTENSION CommonExtension,
    IN PFILE_OBJECT FileObject
    );

NTSTATUS
ClasspMcnControl(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension,
    IN PIRP Irp,
    IN PSCSI_REQUEST_BLOCK Srb
    );

VOID
ClasspRegisterMountedDeviceInterface(
    IN PDEVICE_OBJECT DeviceObject
    );

NTSTATUS
ClasspDisableTimer(
    PDEVICE_OBJECT DeviceObject
    );

NTSTATUS
ClasspEnableTimer(
    PDEVICE_OBJECT DeviceObject
    );

//
// routines for dictionary list support
//

VOID
InitializeDictionary(
    IN PDICTIONARY Dictionary
    );

BOOLEAN
TestDictionarySignature(
    IN PDICTIONARY Dictionary
    );

NTSTATUS
AllocateDictionaryEntry(
    IN PDICTIONARY Dictionary,
    IN ULONGLONG Key,
    IN ULONG Size,
    IN ULONG Tag,
    OUT PVOID *Entry
    );

PVOID
GetDictionaryEntry(
    IN PDICTIONARY Dictionary,
    IN ULONGLONG Key
    );

VOID
FreeDictionaryEntry(
    IN PDICTIONARY Dictionary,
    IN PVOID Entry
    );


NTSTATUS
ClasspAllocateReleaseRequest(
    IN PDEVICE_OBJECT Fdo
    );

VOID
ClasspFreeReleaseRequest(
    IN PDEVICE_OBJECT Fdo
    );

NTSTATUS
ClassReleaseQueueCompletion(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp,
    IN PVOID Context
    );

VOID
ClasspReleaseQueue(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP ReleaseQueueIrp
    );

VOID
ClasspDisablePowerNotification(
    PFUNCTIONAL_DEVICE_EXTENSION FdoExtension
);

//
// class power routines
//

NTSTATUS
ClassDispatchPower(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    );

NTSTATUS
ClassMinimalPowerHandler(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp
    );

//
// Child list routines
//

VOID
ClassAddChild(
    IN PFUNCTIONAL_DEVICE_EXTENSION Parent,
    IN PPHYSICAL_DEVICE_EXTENSION Child,
    IN BOOLEAN AcquireLock
    );

PPHYSICAL_DEVICE_EXTENSION
ClassRemoveChild(
    IN PFUNCTIONAL_DEVICE_EXTENSION Parent,
    IN PPHYSICAL_DEVICE_EXTENSION Child,
    IN BOOLEAN AcquireLock
    );

VOID
ClasspRetryDpcTimer(
    IN PCLASS_PRIVATE_FDO_DATA FdoData
    );

VOID
ClasspRetryRequestDpc(
    IN PKDPC Dpc,
    IN PDEVICE_OBJECT DeviceObject,
    IN PVOID Arg1,
    IN PVOID Arg2
    );

VOID
ClassFreeOrReuseSrb(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension,
    IN PSCSI_REQUEST_BLOCK Srb
    );

VOID
ClassRetryRequest(
    IN PDEVICE_OBJECT SelfDeviceObject,
    IN PIRP           Irp,
    IN LARGE_INTEGER  TimeDelta100ns // in 100ns units
    );

VOID
ClasspBuildRequestEx(
    IN PFUNCTIONAL_DEVICE_EXTENSION Fdo,
    IN PIRP Irp,
    IN PSCSI_REQUEST_BLOCK Srb
    );

NTSTATUS
ClasspAllocateReleaseQueueIrp(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension
    );

NTSTATUS
ClasspInitializeGesn(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension,
    IN PMEDIA_CHANGE_DETECTION_INFO Info
    );

VOID
ClasspSendNotification(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension,
    IN const GUID * Guid,
    IN ULONG  ExtraDataSize,
    IN PVOID  ExtraData
    );

VOID
ClassSendEjectionNotification(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension
    );

VOID
ClasspScanForSpecialInRegistry(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension
    );

VOID
ClasspScanForClassHacks(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension,
    IN ULONG_PTR Data
    );

NTSTATUS
ClasspInitializeHotplugInfo(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension
    );

VOID
ClasspPerfIncrementErrorCount(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension
    );
VOID
ClasspPerfIncrementSuccessfulIo(
    IN PFUNCTIONAL_DEVICE_EXTENSION FdoExtension
    );

NTSTATUS ClasspUpdateDiskProperties(
    IN PDEVICE_OBJECT Fdo
    );


PTRANSFER_PACKET NewTransferPacket(PDEVICE_OBJECT Fdo);
VOID DestroyTransferPacket(PTRANSFER_PACKET Pkt);
VOID EnqueueFreeTransferPacket(PDEVICE_OBJECT Fdo, PTRANSFER_PACKET Pkt);
PTRANSFER_PACKET DequeueFreeTransferPacket(PDEVICE_OBJECT Fdo, BOOLEAN AllocIfNeeded);
VOID SetupReadWriteTransferPacket(PTRANSFER_PACKET pkt, PVOID Buf, ULONG Len, LARGE_INTEGER DiskLocation, PIRP OriginalIrp);
NTSTATUS SubmitTransferPacket(PTRANSFER_PACKET Pkt);
NTSTATUS TransferPktComplete(IN PDEVICE_OBJECT NullFdo, IN PIRP Irp, IN PVOID Context);
NTSTATUS ServiceTransferRequest(PDEVICE_OBJECT Fdo, PIRP Irp);
VOID TransferPacketRetryTimerDpc(IN PKDPC Dpc, IN PVOID DeferredContext, IN PVOID SystemArgument1, IN PVOID SystemArgument2);
BOOLEAN InterpretTransferPacketError(PTRANSFER_PACKET Pkt);
BOOLEAN RetryTransferPacket(PTRANSFER_PACKET Pkt);
VOID EnqueueDeferredClientIrp(PCLASS_PRIVATE_FDO_DATA FdoData, PIRP Irp);
PIRP DequeueDeferredClientIrp(PCLASS_PRIVATE_FDO_DATA FdoData);
VOID InitLowMemRetry(PTRANSFER_PACKET Pkt, PVOID BufPtr, ULONG Len, LARGE_INTEGER TargetLocation);
BOOLEAN StepLowMemRetry(PTRANSFER_PACKET Pkt);
VOID SetupEjectionTransferPacket(TRANSFER_PACKET *Pkt, BOOLEAN PreventMediaRemoval, PKEVENT SyncEventPtr, PIRP OriginalIrp);
VOID SetupModeSenseTransferPacket(TRANSFER_PACKET *Pkt, PKEVENT SyncEventPtr, PVOID ModeSenseBuffer, UCHAR ModeSenseBufferLen, UCHAR PageMode, PIRP OriginalIrp);
VOID SetupDriveCapacityTransferPacket(TRANSFER_PACKET *Pkt, PVOID ReadCapacityBuffer, ULONG ReadCapacityBufferLen, PKEVENT SyncEventPtr, PIRP OriginalIrp, BOOLEAN Use16ByteCdb);
PMDL BuildDeviceInputMdl(PVOID Buffer, ULONG BufferLen);
VOID FreeDeviceInputMdl(PMDL Mdl);
NTSTATUS InitializeTransferPackets(PDEVICE_OBJECT Fdo);
VOID DestroyAllTransferPackets(PDEVICE_OBJECT Fdo);
VOID InterpretCapacityData(PDEVICE_OBJECT Fdo, PREAD_CAPACITY_DATA_EX ReadCapacityData);


extern LIST_ENTRY AllFdosList;