Data Migration API - DMAPI

A horrible X/Open standard for HSM
still used a lot (Cray/SGI DMF, Veritas, IBM)

XFS is the only Linux filesystem with DMAPI support
there was an OpenXDSM project, but it's dead now

DMAPI is incompatible with Linux mount semantics
need to take special care when mounting
thus not part of XFS in Linus' 2.5 tree, only in SGI's tree