NCL has cigar bars on their 'Jewel' class ships...Jewel, Gem, Pearl.

Smoking is a very contentious subject anyway, especially since the Star Princess fire a couple of years ago, however there are no completely smoke free ships. Most allow smoking on balconies & in casino's, all allow it on sections of the outside deckspaces...ie either the port or starboard side.

Your best bet would be to check each cruise line individually once you have decided on which itinerary would suit you the best and then marry up the smoking rules on the ships doing that itinerary as best you can.