> We did a driver port for an SBus FDDI card - starting from the card
> manufacturer's [1] solaris driver.  The original version sucked.  I then
> took out all the 'buffer loaning' stuff and added a data copy to both
> the transmit and receive paths.  New modified driver was much, much
> faster.

FDDI was just generally doomed that way.  

The cards which sun OEM'ed came with a supplier-proprietary driver for
which sources were very closely held even within sun; core
OS/networking developers within sun found it easier to disassemble the
object code when they ran across bugs..

						- Bill