works with device-mapper storage driver?

Just stumbled across this tool and it really seems to solve a common problem. Was using the default Docker setup on CentOS (device-mapper [1] with loop-lvm) and of course the loop file was quickly full.

I since configured Docker to use a proper direct-lvm thinpool volume and it's working fine so far.

So my question is if it's still possible to somehow use this cleanup tool with a devicemapper thin pool since using df on the lvm thinpool volume won't work... at least I don't know how...

[1] https://docs.docker.com/engine/userguide/storagedriver/device-mapper-driver/