[CentOS-virt] using an lvm for kvm vm

Is there a simple way to directly install a vm on an lvm (or proably seperate LVM's for root and swap)? For example something like:

lvcreate -L 10G -n testvm_root vg_myvg lvcreate -L 1G -n testvm_swap

Then somehow setup the VM to be able to directly install and boot the vm from these LV's. How do I do this?

Could you then pause the virtual machine and safely take an LVM snapshot, continue the VM and then mount the snapshot on the host and do a backup?

This would be for CentOS/Redhat 6.

Thanks, Nataraj