Some background:
   Looking @ the comments in
https://review.openstack.org/#/c/192736/8/nova/virt/libvirt/driver.py

we need a way to construct the fully qualified path for a 'network' type disk
which can then be passed to qemu-img for the rebase cmd.

Checking with some folks offline and on IRC, i was suggested to bring this up here.

Is there a way in libvirt to get the full path of network disk that can work with
qemu-img given the virDomain pointer ?

thanx,
deepak