US Patent 8626970 Controlling access by a configuration to an adapter function

Access to an input/output adapter by a configuration is controlled. For each requested access to an adapter, checks are made to determine whether the configuration is authorized to access the adapter. If it is not authorized, then access is denied. If it is authorized, but access should be temporarily blocked, then instruction execution is altered to indicate such. If access is permitted, but should be blocked for another reason (other than temporarily), then access is denied.