There are a number of cleanups that should be done for the ost_id members of various structures.

Access/copying the individual _id and _seq fields should be replaced with the _oi field, and compatibility macros for accessing the individual fields should be removed.

POID/DOID macros should be introduced to print out the _oi fields, similar to PFID/DFID is used for lu_fid fields. Johann had a patch for doing some of this in http://review.whamcloud.com/2004 that needs to be refreshed and resubmitted.