Maybe you'd be better off just using gloves. I find gloves help prevent the callouses from rolling like you say. I only use them for some exercises where it gets too uncomfortable on the hands, otherwise I don't use them.
Straps take the weight off your hands, you need to grip the bars as hard as you can at all times. Do them same with all exercises involving gripping, it helps forearm strength.
I've used chalk in gymnastics on the bars etc, but it helped me to slip when swinging, it did help grip too if you squeeze hard enough. These bars were timber though mind you. If I didn't chalk it'd grip waaay to much.
Chalk on the metal bars might have a different effect, I've never tried it tbh.