From the Carnical website and it might be changed further by next year:
"8. COMPLIANCE WITH RULES, SOLICITATION, SMOKING, DRINKING, ILLEGAL ACTIVITY
(a) Guest agrees during the course of the voyage to follow the directions of the ship’s Master, or his authorized officer. Guest further agrees not to solicit anyone on the vessel for any commercial or professional purposes. Guest agrees that any violation of this Clause may subject guest to disembarkation.
(b) Guest acknowledges that Carnival’s vessels contain non-smoking sections. Guest agrees to refrain from smoking in those sections and agrees that Carnival has the right to disembark the Guest for failure to observe Carnival’s non-smoking policy.
(c) Carnival has designated the Spa stateroom and suite accommodations as an entirely smoke free environment. Guest booked in a Spa cabin agrees to strictly comply with this non-smoking policy and refrain from smoking or allowing any other Guests from smoking in the Spa cabin. Guest further acknowledges and agrees that any violation of this policy shall, in the sole discretion of Carnival, constitute a material breach of this cruise contract. In the event of such breach, Guest forfeits all rights hereunder, including the right to occupy the Spa Cabin and remain on board. Carnival reserves the right to move the Guest(s) to a non-Spa cabin or to disembark the Guest(s), at any port, as determined by Carnival. Carnival shall not be liable for any refund or other compensation or damages whatsoever to any Guest vacated from the Spa Cabin or disembarked pursuant to this provision, or who disembarks because another Guest is so disembarked, and all such Guests forfeit all rights under Carnival’s “Vacation Guarantee.” Guest and Carnival further agree that any violation of the non-smoking policy would also cause Carnival to incur damages, including but not limited to, loss of Guest goodwill, revenue, cleaning, maintenance and/or other costs. Guest and Carnival expressly acknowledge the difficulty of ascertaining the amount of such damages, and therefore agree that a reasonable estimate of the damages for any violation of the non-smoking policy is $250. Guest authorizes a charge in this amount as liquidated damages, as well as repatriation expenses (including airfare) against Guest’s on board charge account, without further notice, for any violation of the non-smoking policy.".