/*++ Copyright (c) 1989, 1990, 1991 Microsoft Corporation Module Name: devctx.c Abstract: This module contains code which implements the DEVICE_CONTEXT object. Routines are provided to reference, and dereference transport device context objects. Currently, there is no need to create them or destroy them, as this is handled at configuration time. If it is later required to dynamically load/unload the transport provider's device object and associated context, then we can add the create and destroy functions. The transport device context object is a structure which contains a system-defined DEVICE_OBJECT followed by information which is maintained by the transport provider, called the context. Author: David Beaver (dbeaver) 1 -July 1991 Environment: Kernel mode Revision History: --*/ #include "precomp.h" #pragma hdrstop #ifdef ALLOC_PRAGMA #ifndef _PNP_POWER #pragma alloc_text(INIT,NbfCreateDeviceContext) #else #pragma alloc_text(PAGE,NbfCreateDeviceContext) #endif #endif VOID NbfRefDeviceContext( IN PDEVICE_CONTEXT DeviceContext ) /*++ Routine Description: This routine increments the reference count on a device context. Arguments: DeviceContext - Pointer to a transport device context object. Return Value: none. --*/ { IF_NBFDBG (NBF_DEBUG_DEVCTX) { NbfPrint0 ("NbfRefDeviceContext: Entered.\n"); } ASSERT (DeviceContext->ReferenceCount > 0); // not perfect, but... (VOID)InterlockedIncrement (&DeviceContext->ReferenceCount); } /* NbfRefDeviceContext */ VOID NbfDerefDeviceContext( IN PDEVICE_CONTEXT DeviceContext ) /*++ Routine Description: This routine dereferences a device context by decrementing the reference count contained in the structure. Currently, we don't do anything special when the reference count drops to zero, but we could dynamically unload stuff then. Arguments: DeviceContext - Pointer to a transport device context object. Return Value: none. --*/ { LONG result; IF_NBFDBG (NBF_DEBUG_DEVCTX) { NbfPrint0 ("NbfDerefDeviceContext: Entered.\n"); } result = InterlockedDecrement (&DeviceContext->ReferenceCount); ASSERT (result >= 0); if (result == 0) { NbfDestroyDeviceContext (DeviceContext); } } /* NbfDerefDeviceContext */ NTSTATUS NbfCreateDeviceContext( IN PDRIVER_OBJECT DriverObject, IN PUNICODE_STRING DeviceName, IN OUT PDEVICE_CONTEXT *DeviceContext ) /*++ Routine Description: This routine creates and initializes a device context structure. Arguments: DriverObject - pointer to the IO subsystem supplied driver object. DeviceContext - Pointer to a pointer to a transport device context object. DeviceName - pointer to the name of the device this device object points to. Return Value: STATUS_SUCCESS if all is well; STATUS_INSUFFICIENT_RESOURCES otherwise. --*/ { NTSTATUS status; PDEVICE_OBJECT deviceObject; PDEVICE_CONTEXT deviceContext; USHORT i; // // Create the device object for NETBEUI. // status = IoCreateDevice( DriverObject, sizeof (DEVICE_CONTEXT) - sizeof (DEVICE_OBJECT) + (DeviceName->Length + sizeof(UNICODE_NULL)), DeviceName, FILE_DEVICE_TRANSPORT, 0, FALSE, &deviceObject); if (!NT_SUCCESS(status)) { return status; } deviceObject->Flags |= DO_DIRECT_IO; deviceContext = (PDEVICE_CONTEXT)deviceObject; // // Initialize our part of the device context. // RtlZeroMemory( ((PUCHAR)deviceContext) + sizeof(DEVICE_OBJECT), sizeof(DEVICE_CONTEXT) - sizeof(DEVICE_OBJECT)); // // Copy over the device name. // deviceContext->DeviceNameLength = DeviceName->Length + sizeof(WCHAR); deviceContext->DeviceName = (PWCHAR)(deviceContext+1); RtlCopyMemory( deviceContext->DeviceName, DeviceName->Buffer, DeviceName->Length); deviceContext->DeviceName[DeviceName->Length/sizeof(WCHAR)] = UNICODE_NULL; // // Initialize device context fields. // deviceContext->NetmanVariables = NULL; // no variables yet. // // Initialize the reference count. // deviceContext->ReferenceCount = 1; #if DBG { UINT Counter; for (Counter = 0; Counter < NUMBER_OF_DCREFS; Counter++) { deviceContext->RefTypes[Counter] = 0; } // This reference is removed by the caller. deviceContext->RefTypes[DCREF_CREATION] = 1; } #endif // // initialize the various fields in the device context // KeInitializeSpinLock (&deviceContext->Interlock); KeInitializeSpinLock (&deviceContext->SpinLock); KeInitializeSpinLock (&deviceContext->LinkSpinLock); KeInitializeSpinLock (&deviceContext->TimerSpinLock); KeInitializeSpinLock (&deviceContext->LoopbackSpinLock); KeInitializeSpinLock (&deviceContext->SendPoolListLock); KeInitializeSpinLock (&deviceContext->RcvPoolListLock); deviceContext->LinkTreeRoot = NULL; deviceContext->LastLink = NULL; deviceContext->LinkTreeElements = 0; deviceContext->LoopbackLinks[0] = NULL; deviceContext->LoopbackLinks[1] = NULL; deviceContext->LoopbackInProgress = FALSE; KeInitializeDpc( &deviceContext->LoopbackDpc, NbfProcessLoopbackQueue, (PVOID)deviceContext ); deviceContext->WanThreadQueued = FALSE; ExInitializeWorkItem( &deviceContext->WanDelayedQueueItem, NbfProcessWanDelayedQueue, (PVOID)deviceContext); deviceContext->UniqueIdentifier = 1; deviceContext->ControlChannelIdentifier = 1; InitializeListHead (&deviceContext->ConnectionPool); InitializeListHead (&deviceContext->AddressPool); InitializeListHead (&deviceContext->AddressFilePool); InitializeListHead (&deviceContext->AddressDatabase); InitializeListHead (&deviceContext->LinkPool); InitializeListHead (&deviceContext->LinkDeferred); InitializeListHead (&deviceContext->PacketWaitQueue); InitializeListHead (&deviceContext->PacketizeQueue); InitializeListHead (&deviceContext->DataAckQueue); InitializeListHead (&deviceContext->DeferredRrQueue); InitializeListHead (&deviceContext->RequestPool); InitializeListHead (&deviceContext->UIFramePool); deviceContext->PacketPool.Next = NULL; deviceContext->ReceivePacketPool.Next = NULL; deviceContext->ReceiveBufferPool.Next = NULL; InitializeListHead (&deviceContext->ReceiveInProgress); InitializeListHead (&deviceContext->ShortList); InitializeListHead (&deviceContext->LongList); InitializeListHead (&deviceContext->PurgeList); InitializeListHead (&deviceContext->LoopbackQueue); InitializeListHead (&deviceContext->FindNameQueue); InitializeListHead (&deviceContext->StatusQueryQueue); InitializeListHead (&deviceContext->IrpCompletionQueue); InitializeListHead (&deviceContext->QueryIndicationQueue); InitializeListHead (&deviceContext->DatagramIndicationQueue); deviceContext->IndicationQueuesInUse = FALSE; // // Equivalent to setting ShortListActive, DataAckQueueActive, // and LinkDeferredActive to FALSE. // deviceContext->a.AnyActive = 0; deviceContext->ProcessingShortTimer = FALSE; deviceContext->DataAckQueueChanged = FALSE; deviceContext->StalledConnectionCount = (USHORT)0; deviceContext->EasilyDisconnected = FALSE; // // Initialize provider statistics. // deviceContext->Statistics.Version = 0x0100; #if 0 deviceContext->Information.Version = 2; // BUGBUG: define TDI_VERSION in TDI.H. deviceContext->Information.MaxTsduSize = NBF_MAX_TSDU_SIZE; deviceContext->Information.MaxDatagramSize = NBF_MAX_DATAGRAM_SIZE; deviceContext->Information.MaxConnectionUserData = NBF_MAX_CONNECTION_USER_DATA; deviceContext->Information.ServiceFlags = NBF_SERVICE_FLAGS; deviceContext->Information.TransmittedTsdus = 0; deviceContext->Information.ReceivedTsdus = 0; deviceContext->Information.TransmissionErrors = 0; deviceContext->Information.ReceiveErrors = 0; deviceContext->Information.MinimumLookaheadData = NBF_MIN_LOOKAHEAD_DATA; deviceContext->Information.MaximumLookaheadData = NBF_MAX_LOOKAHEAD_DATA; deviceContext->Information.DiscardedFrames = 0; deviceContext->Information.OversizeTsdusReceived = 0; deviceContext->Information.UndersizeTsdusReceived = 0; deviceContext->Information.MulticastTsdusReceived = 0; deviceContext->Information.BroadcastTsdusReceived = 0; deviceContext->Information.MulticastTsdusTransmitted = 0; deviceContext->Information.BroadcastTsdusTransmitted = 0; deviceContext->Information.SendTimeouts = 0; deviceContext->Information.ReceiveTimeouts = 0; deviceContext->Information.ConnectionIndicationsReceived = 0; deviceContext->Information.ConnectionIndicationsAccepted = 0; deviceContext->Information.ConnectionsInitiated = 0; deviceContext->Information.ConnectionsAccepted = 0; #endif deviceContext->State = DEVICECONTEXT_STATE_OPENING; // // Loopback buffer is not allocated. // deviceContext->LookaheadContiguous = NULL; // // Initialize the resource that guards address ACLs. // ExInitializeResource (&deviceContext->AddressResource); // // No LSNs are in use. // for (i=0; i<(NETBIOS_SESSION_LIMIT+1); i++) { deviceContext->LsnTable[i] = 0; } deviceContext->NextLsnStart = 1; // // No addresses are in use. // for (i=0; i<256; i++) { deviceContext->AddressCounts[i] = 0; } // // set the netbios multicast address for this network type // for (i=0; iLocalAddress.Address [i] = 0; // set later deviceContext->NetBIOSAddress.Address [i] = 0; } deviceContext->Type = NBF_DEVICE_CONTEXT_SIGNATURE; deviceContext->Size = sizeof (DEVICE_CONTEXT); *DeviceContext = deviceContext; return STATUS_SUCCESS; } VOID NbfDestroyDeviceContext( IN PDEVICE_CONTEXT DeviceContext ) /*++ Routine Description: This routine destroys a device context structure. Arguments: DeviceContext - Pointer to a pointer to a transport device context object. Return Value: None. --*/ { ExDeleteResource (&DeviceContext->AddressResource); IoDeleteDevice ((PDEVICE_OBJECT)DeviceContext); return; }