The co-pilot notified Gatwick Air Traffic Control that they were returning, and was told to take up the holding pattern at Mayfield (10 nm SE of Gatwick) at 3,000 ft. This required several left turns. Unfortunately they could only turn right. ATC obliged with alternative directions. The crew reviewed the warnings displayed on the ECAM screen and responded with the necessary actions. ECAM provides a "help" facility to the pilots and instructed them to do a FLAPS 3 landing at 10 kt faster than normal reference air speed, and to allow for a 20% increase in landing distance. ATC guided them via right turns to intercept Runway 08 ILS centerline at about 8 NM.