The documentation for CRI-O container runtime is lacking in OpenShift Docs.

The only documentation for CRI-O we see is in OpenShift 3.9 Release Notes.

https://docs.openshift.com/container-platform/3.9/release_notes/ocp_3_9_release_notes.html#ocp-39-crio

There is no documentation on how to configure storage for CRI-O.
And more documentation on below points would make docs better.

- Default storage driver for CRI-O and which other storage driver is supported.

- Can container-storage-setup be used with CRI-O as it is used with docker daemon.

  For example when starting CRI-O service, can it use container-storage-setup 
  to setup Volume Group/Logical Volume storage based on configuration in 
  /etc/containers/storage.conf 

- How to migrate existing OpenShift cluster with docker container runtime to CRI-O container runtime.

  For example: OCP 3.7 with docker to OCP 3.9 with CRI-O