(in)appropriate uses for MAXBSIZE

Andriy Gapon avg at freebsd.org
Fri Apr 9 14:29:44 UTC 2010

on 09/04/2010 16:52 Scott Long said the following:
> Storage drivers are insulated from the details of MAXBSIZE by GEOM honoring
> the driver's advertised max-i/o-size attribute.  What I see when I grep through the
> sources are mostly uses in busdma attributes, which themselves probably came
> via cut-n-paste from prior drivers.  I can't come up with any explanation for that
> which makes good design sense, so I'll agree that storage drivers shouldn't
> reference MAXBSIZE.

Should DFLTPHYS be used there?
Or is there a better DMA-specific constant?
Or, perhaps, each driver should just use its won private constant based on its
hardware capabilities?

Andriy Gapon

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