Not familiar with the Airbus but on the Boeing you still have the autopilot and AT. So you are still RVSM compliant.
You will become non RNAV compliant and will need to request for vectors and/or use conventional navigation.
EU airspace requires you to be RNP 5 so continuing might not be an option. Each EU state will have to agree to take you, if not, a tech stop or return to land will be the only choice.
Also the other issues Ollie has mentioned.