> 128 k would be enough, the largest DMA buffer allocated by devices
> is 64k in size (soundcard) and ftape uses 3 32k area's. the scsi
> tape driver also uses quite some space, but also multiple 32k
> regions. floppy driver needs a small piece of dma memory (xxk?)
> and some network/scsi cards do.
I remain unconvinced that solving the problem for a limited
range of known hardware on an ISA bus is a good solution for
an OS that runs on many different system architectures for
which new hardware is being constantly developed by third parties.
I'm not convinced it is even a good solution for an ISA bus.
If you have something like an Adaptec 154x you don't really
want all your I/O going through bounce buffers. A good solution
would bias allocations to suitable memory where possible and
would be able to satisfy explicit requests for certain flavours
of pages.
Mike
-- .----------------------------------------------------------------------. | Mike Jagdis | Internet: mailto:mike@roan.co.uk | | Roan Technology Ltd. | | | 54A Peach Street, Wokingham | Telephone: +44 118 989 0403 | | RG40 1XG, ENGLAND | Fax: +44 118 989 1195 | `----------------------------------------------------------------------'