WDF內部IOCTL不返回輸出

我目前正在編寫一個公開虛擬COM端口的驅動程序。在驅動程序中，我從端口FDO向下發送從PDO IO隊列處理的內部IOCTL。出於某種原因，輸出數據不會寫入所提供的輸出存儲器。WDF內部IOCTL不返回輸出

我已經通過windbg確認IoCtl_Vcp_GetPortInfo（見下文）被調用，並按預期工作。該請求通過STATUS_SUCCESS完成。在我調用WdfRequestComplete的時候，輸出緩衝區有有效的數據。但是，當控制權返回到GetPortInfo（見下文）時，所提供的緩衝區未被覆蓋。我用接收緩衝區的訪問硬件斷點證實了這一點。它不會在WdfIoTargetSendInteralIoctlSynchronously調用期間讀取或寫入。

負責發送IOCTL的代碼如下：

NTSTATUS GetPortInfo(WDFDEVICE device, _Out_ PVCH_PORT_INFO port_info) 
{ 
     NTSTATUS status; 
     WDFIOTARGET io_target; 
     WDF_MEMORY_DESCRIPTOR output_descriptor; 
     PVOID buffer = ExAllocatePoolWithTag(NonPagedPool, sizeof(VCH_PORT_INFO), VCH_POOL_TAG); 

     //WDF_MEMORY_DESCRIPTOR_INIT_BUFFER(&output_descriptor, port_info, sizeof(VCH_PORT_INFO)); 
     WDF_MEMORY_DESCRIPTOR_INIT_BUFFER(&output_descriptor, buffer, sizeof(VCH_PORT_INFO)); 

     io_target = WdfDeviceGetIoTarget(device); 
     status = WdfIoTargetSendInternalIoctlSynchronously(io_target, NULL, IOCTL_VCP_INTERNAL_GET_PORT_INFO, NULL, &output_descriptor, NULL, NULL); 
     DbgBreakPoint(); 
     if (!NT_SUCCESS(status)) 
       return status; 

     memcpy(port_info, buffer, sizeof(VCH_PORT_INFO)); 
     ExFreePoolWithTag(buffer, VCH_POOL_TAG); 

     return STATUS_SUCCESS; 
}

處理該IOCTL的代碼：

NTSTATUS IoCtl_Vcp_GetPortInfo(WDFDEVICE device, WDFREQUEST request) 
{ 
     NTSTATUS status; 
     PVCH_PORT_INFO buffer; 
     PPORT_PDO_DESCRIPTOR descriptor = PortPdoGetContext(device); 

     status = WdfRequestRetrieveOutputBuffer(request, sizeof(VCH_PORT_INFO), (PVOID*)&buffer, NULL); 
     if (!NT_SUCCESS(status)) 
       return status; 

     buffer->Address = descriptor->Address; 
     buffer->ForceComIndex = FALSE; // TODO: Implement 
     buffer->Writeable = descriptor->Writeable; 
     DbgBreakPoint(); 
     return STATUS_SUCCESS; 
}

的IOCTL代碼定義：

#define DEVICE_TYPE_VIRTUAL_COM_PORT 0xC51 
#define IOCTL_VCP_INTERNAL_GET_PORT_INFO CTL_CODE(DEVICE_TYPE_VIRTUAL_COM_PORT, 0x30, METHOD_BUFFERED, FILE_READ_DATA)

來源

2016-07-27 GregoryComer

設置請求帶有輸出字節數的完成信息修復了問題。

來源

2016-07-27 21:10:43 GregoryComer

WDF內部IOCTL不返回輸出

回答

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