mirror of
https://github.com/reactos/reactos.git
synced 2025-03-10 18:24:02 +00:00
1f377076d7
Not all files are included, but these are necessary to compile cdrom driver. So far it can only be statically linked with drivers, a proper implementation requires wdfldr helper driver
119 lines
3.6 KiB
C++
119 lines
3.6 KiB
C++
/*++
|
|
|
|
Copyright (c) Microsoft. All rights reserved.
|
|
|
|
Module Name:
|
|
|
|
EventQueueKm.cpp
|
|
|
|
Abstract:
|
|
|
|
This module implements kernel mode specific functionality of event queue
|
|
|
|
This functionality needed to be separated out since the KM portion takes
|
|
a reference on driver object because KM MxWorkItem::_Free does not wait for
|
|
callback to return (i.e. rundown synchronously).
|
|
|
|
MxWorkItem::_Free in UM currently waits for callback to return (i.e. runs
|
|
down synchronously) hence does not need a reference on driver/devstack
|
|
object (see comments on top of MxWorkItemUm.h file).
|
|
|
|
In future if UM work-item is made similar to km workitem, UMDF may need to
|
|
ensure that modules stay loaded, though the mechanism to ensure that would
|
|
likely be different from a reference on the driver. It would likely be a
|
|
reference on the devicestack object.
|
|
|
|
Environment:
|
|
|
|
Kernel mode only
|
|
|
|
Revision History:
|
|
|
|
|
|
|
|
|
|
--*/
|
|
|
|
#include "pnppriv.hpp"
|
|
|
|
VOID
|
|
FxWorkItemEventQueue::QueueWorkItem(
|
|
VOID
|
|
)
|
|
{
|
|
//
|
|
// The work item will take a reference on KMDF itself. This will keep KMDF's
|
|
// image around (but not necessarily prevent DriverUnload from being called)
|
|
// so that the code after we set the done event will be in memory and not
|
|
// unloaded. We must do this because there is no explicit reference between
|
|
// the client driver and KMDF, so when the io manager calls the client's
|
|
// DriverUnload, it has no way of managing KMDF's ref count to stay in memory
|
|
// when the loader unloads KMDF explicitly in response to DriverUnload.
|
|
//
|
|
// We manually take a reference on the client so that we provide the same
|
|
// functionality that IO workitems do. The client driver's image will have
|
|
// a reference on it after it has returned.
|
|
//
|
|
|
|
|
|
|
|
|
|
Mx::MxReferenceObject(m_PkgPnp->GetDriverGlobals()->Driver->GetDriverObject());
|
|
|
|
//
|
|
// Prevent FxDriverGlobals from being deleted until the workitem finishes
|
|
// its work. In case of a bus driver with a PDO in removed
|
|
// state, if the bus is removed, the removal of PDO may happen in a workitem
|
|
// and may result in unload routine being called before the PDO package is
|
|
// deallocated. Since FxPool deallocation code touches FxDriverGlobals
|
|
// (a pointer of which is located in the header of each FxPool allocated
|
|
// object), taking this ref prevents the globals from going away until a
|
|
// corresponding deref at the end of workitem.
|
|
//
|
|
m_PkgPnp->GetDriverGlobals()->ADDREF((PVOID)_WorkItemCallback);
|
|
|
|
m_WorkItem.Enqueue(
|
|
(PMX_WORKITEM_ROUTINE) _WorkItemCallback,
|
|
(FxEventQueue*) this);
|
|
}
|
|
|
|
VOID
|
|
FxWorkItemEventQueue::_WorkItemCallback(
|
|
__in MdDeviceObject DeviceObject,
|
|
__in PVOID Context
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
This is the work item that attempts to run the machine on a thread
|
|
separate from the one the caller was using. It implements step 9 above.
|
|
|
|
--*/
|
|
{
|
|
FxWorkItemEventQueue* This = (FxWorkItemEventQueue*) Context;
|
|
PFX_DRIVER_GLOBALS pFxDriverGlobals;
|
|
|
|
UNREFERENCED_PARAMETER(DeviceObject);
|
|
|
|
MdDriverObject pDriverObject;
|
|
|
|
pFxDriverGlobals = This->m_PkgPnp->GetDriverGlobals();
|
|
|
|
//
|
|
// Capture the driver object before we call the EventQueueWoker() because
|
|
// the time it returns, This could be freed.
|
|
|
|
|
|
|
|
pDriverObject = pFxDriverGlobals->Driver->GetDriverObject();
|
|
|
|
This->EventQueueWorker();
|
|
|
|
//
|
|
// Release the ref on FxDriverGlobals taken before queuing this workitem.
|
|
//
|
|
pFxDriverGlobals->RELEASE((PVOID)_WorkItemCallback);
|
|
|
|
Mx::MxDereferenceObject(pDriverObject);
|
|
}
|
|
|