tapewmi.c

This sample is a working example of Exabyte2 Tape Minidriver. This module contains device-specific r

/*++

Copyright (C) Microsoft Corporation, 1999

Module Name:

    tapewmi.c

Abstract:

    This is the tape class driver - WMI support routines.

Environment:

    kernel mode only

Revision History:

--*/

#include "tape.h"

//
// List guids supported by Tape driver
//
GUIDREGINFO TapeWmiGuidList[] =
{
   {
      WMI_TAPE_DRIVE_PARAMETERS_GUID,
      1,
      0
   },

   {
      WMI_TAPE_MEDIA_PARAMETERS_GUID,
      1,
      0
   },

   {
      WMI_TAPE_PROBLEM_WARNING_GUID,
      1,
      WMIREG_FLAG_EVENT_ONLY_GUID
   },

   {
      WMI_TAPE_PROBLEM_IO_ERROR_GUID,
      1,
      WMIREG_FLAG_EXPENSIVE
   },

   {
      WMI_TAPE_PROBLEM_DEVICE_ERROR_GUID,
      1,
      WMIREG_FLAG_EXPENSIVE
   },

   {
      WMI_TAPE_SYMBOLIC_NAME_GUID,
      1,
      0
   }
};

GUID TapeDriveProblemEventGuid = WMI_TAPE_PROBLEM_WARNING_GUID;

//
// GUID index. It should match the guid list
// defined above
//
#define TapeDriveParametersGuid            0
#define TapeMediaCapacityGuid              1
#define TapeDriveProblemWarningGuid        2
#define TapeDriveProblemIoErrorGuid        3
#define TapeDriveProblemDevErrorGuid       4
#define TapeSymbolicNameGuid               5


#ifdef ALLOC_PRAGMA

#pragma alloc_text(PAGE, TapeWMIControl)
#pragma alloc_text(PAGE, TapeQueryWmiRegInfo)
#pragma alloc_text(PAGE, TapeQueryWmiDataBlock)
#pragma alloc_text(PAGE, TapeExecuteWmiMethod)
#pragma alloc_text(PAGE, TapeWmiFunctionControl)
#pragma alloc_text(PAGE, TapeSetWmiDataBlock)
#pragma alloc_text(PAGE, TapeSetWmiDataItem)
#pragma alloc_text(PAGE, TapeEnableDisableDrivePolling)

#endif


NTSTATUS
TapeQueryWmiRegInfo(
    IN PDEVICE_OBJECT DeviceObject,
    OUT ULONG *RegFlags,
    OUT PUNICODE_STRING InstanceName
    )
/*++

Routine Description:

    This routine is a callback into the driver to retrieve the list of
    guids or data blocks that the driver wants to register with WMI. This
    routine may not pend or block. Driver should NOT call
    ClassWmiCompleteRequest.

Arguments:

    DeviceObject is the device whose data block is being queried

    *RegFlags returns with a set of flags that describe the guids being
        registered for this device. If the device wants enable and disable
        collection callbacks before receiving queries for the registered
        guids then it should return the WMIREG_FLAG_EXPENSIVE flag. Also the
        returned flags may specify WMIREG_FLAG_INSTANCE_PDO in which case
        the instance name is determined from the PDO associated with the
        device object. Note that the PDO must have an associated devnode. If
        WMIREG_FLAG_INSTANCE_PDO is not set then Name must return a unique
        name for the device.

    InstanceName returns with the instance name for the guids if
        WMIREG_FLAG_INSTANCE_PDO is not set in the returned *RegFlags. The
        caller will call ExFreePool with the buffer returned.


Return Value:

    status

--*/
{

    PAGED_CODE();

   //
   // Use devnode for FDOs
   //
   *RegFlags = WMIREG_FLAG_INSTANCE_PDO;
   return STATUS_SUCCESS;
}

NTSTATUS
TapeQueryWmiDataBlock(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp,
    IN ULONG GuidIndex,
    IN ULONG BufferAvail,
    OUT PUCHAR Buffer
    )
/*++

Routine Description:

    This routine is a callback into the driver to query for the contents of
    a data block. When the driver has finished filling the data block it
    must call ClassWmiCompleteRequest to complete the irp. The driver can
    return STATUS_PENDING if the irp cannot be completed immediately.

Arguments:

    DeviceObject is the device whose data block is being queried

    Irp is the Irp that makes this request

    GuidIndex is the index into the list of guids provided when the
        device registered

    BufferAvail on has the maximum size available to write the data
        block.

    Buffer on return is filled with the returned data block


Return Value:

    status

--*/
{
   NTSTATUS status = STATUS_SUCCESS;
   PFUNCTIONAL_DEVICE_EXTENSION fdoExtension = DeviceObject->DeviceExtension;
   PCOMMON_DEVICE_EXTENSION commonExtension = DeviceObject->DeviceExtension;
   PTAPE_INIT_DATA_EX tapeInitData;
   ULONG sizeNeeded;
   ULONG wmiMethod;
   TAPE_WMI_OPERATIONS  wmiWorkItem;
   TAPE_PROCESS_COMMAND_ROUTINE commandRoutine;
   
   PAGED_CODE();

   DebugPrint((3, 
               "TapeQueryWmiDataBlock : Device %p, Irp %p, GuidIndex %d",
               "  BufferAvail %lx Buffer %lx\n",   
               DeviceObject, Irp, GuidIndex, BufferAvail, Buffer));

   tapeInitData = (PTAPE_INIT_DATA_EX) (fdoExtension->CommonExtension.DriverData);
   switch (GuidIndex) {
      case TapeDriveParametersGuid: {
         TAPE_GET_DRIVE_PARAMETERS dataBuffer;
         PWMI_TAPE_DRIVE_PARAMETERS outBuffer;

         sizeNeeded = sizeof(WMI_TAPE_DRIVE_PARAMETERS);
         if (BufferAvail < sizeNeeded) {
            status = STATUS_BUFFER_TOO_SMALL;
            break;
         }
  
         RtlZeroMemory(&dataBuffer, sizeof(TAPE_GET_DRIVE_PARAMETERS));
         commandRoutine = tapeInitData->GetDriveParameters;
         status = TapeWMIControl(DeviceObject, commandRoutine,
                                 (PUCHAR)&dataBuffer);

         if (NT_SUCCESS(status)) {
            outBuffer = (PWMI_TAPE_DRIVE_PARAMETERS)Buffer;
            outBuffer->MaximumBlockSize = dataBuffer.MaximumBlockSize;
            outBuffer->MinimumBlockSize = dataBuffer.MinimumBlockSize;
            outBuffer->DefaultBlockSize = dataBuffer.DefaultBlockSize;
            outBuffer->MaximumPartitionCount = dataBuffer.MaximumPartitionCount;
            if ((dataBuffer.FeaturesLow) & TAPE_DRIVE_COMPRESSION) {
               outBuffer->CompressionCapable = TRUE;
            } else {
               outBuffer->CompressionCapable = FALSE;
            }
            outBuffer->CompressionEnabled = dataBuffer.Compression;
            outBuffer->HardwareErrorCorrection = dataBuffer.ECC;
            outBuffer->ReportSetmarks = dataBuffer.ReportSetmarks;
         }

         break;
      }

      case TapeMediaCapacityGuid: {
         TAPE_GET_MEDIA_PARAMETERS dataBuffer;
         PWMI_TAPE_MEDIA_PARAMETERS outBuffer;

         sizeNeeded = sizeof(WMI_TAPE_MEDIA_PARAMETERS);
         if (BufferAvail < sizeNeeded) {
            status = STATUS_BUFFER_TOO_SMALL;
            break;
         } 

         RtlZeroMemory(&dataBuffer, sizeof(TAPE_GET_MEDIA_PARAMETERS));
         commandRoutine = tapeInitData->GetMediaParameters;      
         status = TapeWMIControl(DeviceObject, commandRoutine,
                                 (PUCHAR)&dataBuffer);

         if (NT_SUCCESS(status)) {
            outBuffer = (PWMI_TAPE_MEDIA_PARAMETERS)Buffer;
            outBuffer->AvailableCapacity = dataBuffer.Remaining.QuadPart;
            outBuffer->MaximumCapacity = dataBuffer.Capacity.QuadPart;
            outBuffer->BlockSize = dataBuffer.BlockSize;
            outBuffer->PartitionCount = dataBuffer.PartitionCount;
            outBuffer->MediaWriteProtected = dataBuffer.WriteProtected;
         }

         break;
      }

      case TapeSymbolicNameGuid: {

          //
          // We need buffer large enough to put the string TapeN
          // where N is an integer. We'll take 32 wide chars
          //
          sizeNeeded = sizeof(WCHAR) * 32;
          if (BufferAvail < sizeNeeded) {
              status = STATUS_BUFFER_TOO_SMALL;
              break;
          }

          RtlZeroMemory(Buffer, sizeof(WCHAR) * 32);
          swprintf((PWCHAR)(Buffer + sizeof(USHORT)),  L"Tape%d", 
                   fdoExtension->DeviceNumber);
          *((PUSHORT)Buffer) = wcslen((PWCHAR)(Buffer + sizeof(USHORT))) * sizeof(WCHAR);

          status = STATUS_SUCCESS;
          break;
      }

      case TapeDriveProblemIoErrorGuid: {
         sizeNeeded = sizeof(WMI_TAPE_PROBLEM_WARNING);
         if (BufferAvail < sizeNeeded) {
            status = STATUS_BUFFER_TOO_SMALL;
            break;
         }

         commandRoutine = tapeInitData->TapeWMIOperations;
         wmiWorkItem.Method = TAPE_QUERY_IO_ERROR_DATA;
         wmiWorkItem.DataBufferSize = BufferAvail;
         wmiWorkItem.DataBuffer = Buffer;
         status = TapeWMIControl(DeviceObject, commandRoutine,
                                 (PUCHAR)&wmiWorkItem);
         break;
      }

      case TapeDriveProblemDevErrorGuid: {
         sizeNeeded = sizeof(WMI_TAPE_PROBLEM_WARNING);
         if (BufferAvail < sizeNeeded) {
            status = STATUS_BUFFER_TOO_SMALL;
            break;
         }

         commandRoutine = tapeInitData->TapeWMIOperations;
         wmiWorkItem.Method = TAPE_QUERY_DEVICE_ERROR_DATA;
         wmiWorkItem.DataBufferSize = BufferAvail;
         wmiWorkItem.DataBuffer = Buffer;
         status = TapeWMIControl(DeviceObject, commandRoutine,
                                 (PUCHAR)&wmiWorkItem);
         break;
      }

      default:{
         sizeNeeded = 0;
         status = STATUS_WMI_GUID_NOT_FOUND;
         break;
      }
   } // switch (GuidIndex)

   DebugPrint((3, "TapeQueryWmiData : Device %p, Irp %p, ",
                  "GuidIndex %d, status %x\n",
                  DeviceObject, Irp, GuidIndex, status));

   status = ClassWmiCompleteRequest(DeviceObject,
                                    Irp,
                                    status,
                                    sizeNeeded,
                                    IO_NO_INCREMENT);

   return status;
}

NTSTATUS
TapeExecuteWmiMethod(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp,
    IN ULONG GuidIndex,
    IN ULONG MethodId,
    IN ULONG InBufferSize,
    IN ULONG OutBufferSize,
    IN PUCHAR Buffer
    )
/*++

Routine Description:

    This routine is a callback into the driver to execute a method. When the
    driver has finished filling the data block it must call
    ClassWmiCompleteRequest to complete the irp. The driver can
    return STATUS_PENDING if the irp cannot be completed immediately.

Arguments:

    DeviceObject is the device whose data block is being queried

    Irp is the Irp that makes this request

    GuidIndex is the index into the list of guids provided when the
        device registered

    MethodId has the id of the method being called

    InBufferSize has the size of the data block passed in as the input to
        the method.

    OutBufferSize on entry has the maximum size available to write the
        returned data block.

    Buffer is filled with the returned data block


Return Value:

    status

--*/
{
   NTSTATUS status = STATUS_SUCCESS;

   PAGED_CODE();

   status = ClassWmiCompleteRequest(DeviceObject,
                                    Irp,
                                    status,
                                    0,
                                    IO_NO_INCREMENT);

   return status;
}

NTSTATUS
TapeWmiFunctionControl(
    IN PDEVICE_OBJECT DeviceObject,
    IN PIRP Irp,
    IN ULONG GuidIndex,
    IN CLASSENABLEDISABLEFUNCTION Function,
    IN BOOLEAN Enable
    )
/*++

Routine Description:

    This routine is a callback into the driver to enabled or disable event
    generation or data block collection. A device should only expect a
    single enable when the first event or data consumer enables events or
    data collection and a single disable when the last event or data
    consumer disables events or data collection. Data blocks will only
    receive collection enable/disable if they were registered as requiring
    it.

    This function can be used to enable\disable event generation. The event
    mentioned here is Tape Drive Problem Warning event. This event is disabled
    by default. If any application is interested in being notified of drive 
    problems, it can enable this event generation.
    
Arguments:

    DeviceObject is the device whose data block is being queried

    GuidIndex is the index into the list of guids provided when the
        device registered

    Function specifies which functionality is being enabled or disabled

    Enable is TRUE then the function is being enabled else disabled

Return Value: