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To: Brooks Davis <brooks@freebsd.org>
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Subject: Re: PERFORCE change 213107 for review
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On 19 Jun 2012, at 01:29, Brooks Davis wrote:

> Change 213107 by brooks@brooks_ecr_current on 2012/06/19 00:28:56
>=20
> 	Allow non-PAGE_SIZE sized and aligned regions as long as they =
are
> 	smaller than a page.  This allows us to provide trivial access =
to things
> 	like the buttons and switches bytes.


For the regular read(2)/write(2) interface, non-page-aligned and -sized =
regions are fine, but for mmap(2) they are problematic. Perhaps we =
should allow them only if mmap(2) access isn't requested in the =
device.hints configuration -- or at least device_printf() a warning =
about mmap(2) being disallowed?

Robert=