fVMBusCookie
status = fVMBus->open_channel(fVMBusCookie, fChannelID, fRingGPADL, txTotalLength,
status_t status = fVMBus->close_channel(fVMBusCookie, fChannelID);
fVMBus->signal_channel(fVMBusCookie, fChannelID);
return fVMBus->allocate_gpadl(fVMBusCookie, fChannelID, length, _buffer, _gpadl);
return fVMBus->free_gpadl(fVMBusCookie, fChannelID, gpadl);
gDeviceManager->get_driver(parent, (driver_module_info**)&fVMBus, (void**)&fVMBusCookie);
fVMBus->signal_channel(fVMBusCookie, fChannelID);
return fVMBus->get_version(fVMBusCookie);
hyperv_bus fVMBusCookie;