fxfileobjectum.cpp

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/*++
 
Copyright (c) Microsoft Corporation
 
Module Name:
 
    FxFileObjectUm.hpp
 
Abstract:
 
    This module implements a frameworks managed FileObject
 
Author:
 
 
 
Environment:
 
    User mode only
 
Revision History:
 
 
 
--*/
 
#include "coreprivshared.hpp"
 
// Tracing support
extern "C" {
#include "FxFileObjectUm.tmh"
}
 
VOID
FxFileObject::SetFileObjectContext(
    _In_ MdFileObject WdmFileObject,
    _In_ WDF_FILEOBJECT_CLASS NormalizedFileClass,
    _In_ MdIrp Irp,
    _In_ FxDevice* Device
    )
{
    IWudfIoIrp* pIoIrp;
    HRESULT hrQi;
 
    UNREFERENCED_PARAMETER(WdmFileObject);
    UNREFERENCED_PARAMETER(NormalizedFileClass);
 
    ASSERT(NormalizedFileClass == WdfFileObjectWdfCannotUseFsContexts);
 
    //
    // In UMDF, fx file object is stored by host. Host passes it back to
    // framework as a parameter to irp dispatch routine.
    //
    hrQi = Irp->QueryInterface(IID_IWudfIoIrp, (PVOID*)&pIoIrp);
    FX_VERIFY(INTERNAL, CHECK_QI(hrQi, pIoIrp));
    pIoIrp->Release();
 
    pIoIrp->SetFrameworkFileObjectContext(Device->GetDeviceObject(),
                                          (IUnknown *) this);
}
 
VOID
FxFileObject::Initialize(
    _In_ MdIrp CreateIrp
    )
{
    FxIrp irp(CreateIrp);
    IWudfIoIrp* ioIrp = irp.GetIoIrp();
    IUnknown* pCxtFramework = NULL;
    FxFileObject* pRelatedFileObj = NULL;
 
    //
    // Get framework related file object.
    //
    ioIrp->GetFrameworkRelatedFileObjectContext(
                                    m_Device->GetDeviceObject(),
                                    &pCxtFramework
                                    );
    if (pCxtFramework != NULL) {
        pRelatedFileObj = (FxFileObject*) pCxtFramework;
 
        pRelatedFileObj->AddRef();
        this->m_RelatedFileObject = pRelatedFileObj;
    }
 
    return;
}
 
_Must_inspect_result_
NTSTATUS
FxFileObject::UpdateProcessKeepAliveCount(
    _In_ BOOLEAN Increment
    )
{
    MdFileObject pWdmFO = GetWdmFileObject();
    FxDevice* pDevice = GetDevice();
 
    if (pWdmFO == NULL) {
        FX_VERIFY(DRIVER(BadArgument, TODO), TRAPMSG("Cannot increment "
            "process keep alive count from a file object that doesn't "
            "have a WDM file object"));
        return STATUS_INVALID_PARAMETER;
    }
 
    //
    // Validate that driver set UmdfFsContextUsePolicy = CannotUseFsContexts
    //
    if (pDevice->m_FsContextUsePolicy != WdfCannotUseFsContexts) {
        FX_VERIFY(DRIVER(BadArgument, TODO), TRAPMSG("Cannot increment "
            "process keep alive count unless UmdfFsContextUsePolicy INF "
            "directive is set to WdfCannotUseFsContexts"));
        return STATUS_INVALID_DEVICE_REQUEST;
    }
 
    return pDevice->NtStatusFromHr(
        pDevice->GetDeviceStack2()->
            UpdateProcessKeepAliveCount(pWdmFO, Increment));
}