> I've already gotten mail suggesting I switch to OpenBSD.  Well, I'm
 > not currently looking at this solution, but why can't we have a
 > machine dependent bounce buffer solution while we wait for a machine
 > independent solution.  It's not like we don't have other machine
 > dependent code.

    Umm, since no one seems to have pointed it out....  Just cuz it
ain't in the master tree doesn't mean it doesn't exist.  ISA DMA has
been available for NetBSD for some time; I was using it in my 32MB 486
with an aha1542 without any difficulty for a couple of months.  I
don't know if its actively being maintained at this point, but you can
get it from ftp://bseis.eis.cs.tu-bs.de/pub/hannken/isadma-patch.