DH is tired of our 4 year old sleeping with us!
If your son is happy with it, a bed on the floor in the sleeping bag sounds nice.
Or, your husband can use a different bedroom. I know that sounds an awful lot like kicking daddy out, but I tell you, the nights that mine chose to move to another bedroom were actually the easiest on me because I stopped stressing about whether he was being kept awake or not. And after a few nights of peaceful rest, he became convinced as well. ETA: I did find it hard to stop the occasional chainsaw snores, but this was a reasonable tradeoff, I think. At least he was sleeping!
But that won't solve the problem of ds running races on your back and head at night. A little extra room might help, but he might still need to end up on the floor.
Maybe he'd feel better if you or his dad came in and slept on his floor? And he stayed in his own bed?
All ideas to consider.