Did you resolve your disk space issue?
The filling of your disk has surely caused corruption in your FlowFile repository. If you are not worried about losing data that was queued in your dataflow, you could simply delete your FlowFile and content repositories and NiFi will generate new empty repositories on startup.
any other logs or details. how much disk space? ram? how many nodes? where is zookeeper running? are you using ambari? which version of NiFi? HDF?