[vioser]: Handle surprise removal for serial ports

When the Virtio serial port gets surprise removed, let's complete the pending read request sent by QGA with STATUS_DELETE_PENDING. If QGA is run as a service, it reports an error, closes handles to all Virtio serial devices and starts waiting for their reappearance. Closing the handles permits the PnP Manager to remove the serial devices. If the handles stayed open, the system would hang indefinitely.

Signed-Off-By: Martin Drab <[email protected]>

Author: Martin Drab

vioserial/sys/Port.c

@@ -14,13 +14,15 @@ EVT_WDF_REQUEST_CANCEL VIOSerialPortReadRequestCancel;
 EVT_WDF_DEVICE_D0_ENTRY VIOSerialPortEvtDeviceD0Entry;
 EVT_WDF_DEVICE_D0_EXIT VIOSerialPortEvtDeviceD0Exit;
 EVT_WDF_DEVICE_QUERY_REMOVE VIOSerialPortEvtDeviceQueryRemove;
+EVT_WDF_DEVICE_SURPRISE_REMOVAL VIOSerialPortEvtDeviceSurpriseRemoval;
 
 #ifdef ALLOC_PRAGMA
 #pragma alloc_text(PAGE, VIOSerialDeviceListCreatePdo)
 #pragma alloc_text(PAGE, VIOSerialPortWrite)
 #pragma alloc_text(PAGE, VIOSerialPortDeviceControl)
 #pragma alloc_text(PAGE, VIOSerialPortEvtDeviceD0Entry)
 #pragma alloc_text(PAGE, VIOSerialPortEvtDeviceQueryRemove)
+#pragma alloc_text(PAGE, VIOSerialPortEvtDeviceSurpriseRemoval)
 #endif
 
 PVIOSERIAL_PORT
@@ -364,6 +366,7 @@ VIOSerialDeviceListCreatePdo(IN WDFCHILDLIST DeviceList,
         PnpPowerCallbacks.EvtDeviceD0Entry = VIOSerialPortEvtDeviceD0Entry;
         PnpPowerCallbacks.EvtDeviceD0Exit = VIOSerialPortEvtDeviceD0Exit;
         PnpPowerCallbacks.EvtDeviceQueryRemove = VIOSerialPortEvtDeviceQueryRemove;
+        PnpPowerCallbacks.EvtDeviceSurpriseRemoval = VIOSerialPortEvtDeviceSurpriseRemoval;
         WdfDeviceInitSetPnpPowerEventCallbacks(ChildInit, &PnpPowerCallbacks);
 
         WDF_OBJECT_ATTRIBUTES_INIT_CONTEXT_TYPE(&attributes, RAWPDO_VIOSERIAL_PORT);
@@ -1292,6 +1295,33 @@ NTSTATUS VIOSerialPortEvtDeviceQueryRemove(WDFDEVICE Device)
     return STATUS_SUCCESS;
 }
 
+VOID VIOSerialPortEvtDeviceSurpriseRemoval(WDFDEVICE Device)
+{
+    WDFREQUEST readRequest = NULL;
+    PRAWPDO_VIOSERIAL_PORT pdoData = RawPdoSerialPortGetData(Device);
+    PVIOSERIAL_PORT port = pdoData->port;
+
+    TraceEvents(TRACE_LEVEL_INFORMATION, DBG_PNP, "--> %s\n", __FUNCTION__);
+
+    WdfSpinLockAcquire(port->InBufLock);
+    readRequest = port->PendingReadRequest;
+    port->PendingReadRequest = NULL;
+    if (readRequest != NULL)
+    {
+        if (WdfRequestUnmarkCancelable(readRequest) != STATUS_CANCELLED)
+        {
+            WdfRequestCompleteWithInformation(readRequest, STATUS_DELETE_PENDING, 0L);
+        }
+    }
+
+    port->Removed = TRUE;
+    WdfSpinLockRelease(port->InBufLock);
+
+    TraceEvents(TRACE_LEVEL_INFORMATION, DBG_PNP, "<-- %s\n", __FUNCTION__);
+
+    return;
+}
+
 NTSTATUS VIOSerialPortEvtDeviceD0Entry(IN WDFDEVICE Device, IN WDF_POWER_DEVICE_STATE PreviousState)
 {
     PVIOSERIAL_PORT port = RawPdoSerialPortGetData(Device)->port;