What does "you'll be in your whack" mean?

Another colorful expression from that British movie I mentioned earlier. The context of the quote here is that there are these guys trying to smuggle ecstasy pills, and there's another guy hosting their meeting in exchange for a below-the-table bribe, though he's not directly involved himself. The host is anxious and wants them to move on quickly from the spot he's providing, as he's a civilian -- he doesn't "want to get nicked." One of the smugglers retorts back to him, "Don't worry, you'll be in your whack", in what sounds like a Cockney English accent.

So my questions are: What does this phrase mean, exactly? What does the whack add to the meaning? Is it common amongst certain types of British English speakers?

Solution 1:

Green's Dictionary of Slang has in whack (with) as taking equal shares, and also whack as a share or portion. I think that is what is meant here; "you'll get your share".

Among the numerous other meanings of whack is also a prison sentence, and the phrase cop your whack means "to get your just deserts". Perhaps this sentence is a play on the multiple meanings; "you'll get your share of the good things - and the bad".