Headroom is ample even for tall passengers and as you can see below, with the front seat adjusted to my driving position, there is good amount of legroom for a six foot plus passenger at the rear. (motorbeam.com)
Better headroom, decent amount of knee room and good amount of legroom compared to the previous Swift. (auto.ndtv.com)
There's a good amount of legroom and adequate headroom too. (autocarindia.com)