So this implies that there is really only one mapping outstanding at any point in time (less the cache issue). Right? So why is there a map count as an fmr attribute? Its seems like just an arbitrary limit put on how many times you can map an fmr before unmaping. -and- once you unmap you can start mapping again up to the map count... ??
On Thu, 2006-02-23 at 12:39 -0800, Roland Dreier wrote: > Steve> Lets say a FMR is allocated with a map count of 4. And the > Steve> FMR is mapped 4 times, then unmapped. Are the underlying > Steve> MRs still valid and setup for RDMA from the HW perspective? > Steve> Or are they marked "INVALID" as part of unmapping? IE: Do > Steve> they remain valid up to unmap or up to dealloc of the FMR > > They are not valid after the unmap operation. In fact, old mappings > are probably not valid after the FMR is remapped; the issue for > Mellanox hardware is that the old mapping might still be hanging > around in an internal cache somewhere. However the unmap_fmr > operation flushes all these caches, so all old mappings are gone after > an FMR is unmapped. > > - R. _______________________________________________ openib-general mailing list [email protected] http://openib.org/mailman/listinfo/openib-general To unsubscribe, please visit http://openib.org/mailman/listinfo/openib-general
