It sounds as if you're looking for the utilization level of SAN host filesystems.  Like you'd see in the output of "df" on a Unix machine.  If that's the case, you're not going to find that in OCI by default.  Since we don't instrument the SAN hosts, we don't collect that data.  There is a way to import it from any other database that might provide it, via the FSLU data source.  This associates capacity numbers with mount points or drive letters on the server, but does not tie it back to the storage LUN(s) underlying the mount point.