[NFS-Ganesha-Support] FSAL_CEPH - exporting subdirectories

I have a cephfs filesystem and I want to export a subdirectory of my cephfs tree. Is this possible or do I have to export the entire tree from the root? If it is possible, then is it also possible to define exports for multiple subdirectories of my cephfs FS such as /cephfs/exports/foo and /cephfs/exports/bar as 2 separate exports?