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Re: Unifying /dev/{mem,kmem,zero,null} implementations

On Tue, Feb 19, 2008 at 06:18:53PM +0100, Manuel Bouyer wrote:
> On Tue, Feb 19, 2008 at 04:29:55PM +0100, Joerg Sonnenberger wrote:
> > Hi all,
> >
> > unifies the implementation of /dev/{mem,kmem,zero,null} in MI code and
> > makes it MPsafe. This is useful as writing to /dev/null is not that
> > unknown :-)
> > 
> > This needs quite a bit attention from portmasters and testing:
> > - the address returned by mmap of /dev/mem is not consistent on all
> > ports, I have no idea if it works on those where atop() doesn't exist.
> > - on i386, the special /dev/io semantic for COMPAT_10 and COMPAT_FREEBSD
> > is lost at the moment -- do we want to keep that? It would mean another
> > platform hook.
> If /dev/io is still used on FreeBSD this way, I think we want to keep it.
> I did use a FreeBSD binary-only tool which used /dev/io to drive the
> parallel port (which was connected to some chip programmer - I don't
> remember which one exactly).

In case it hasn't been noted, FreeBSD still uses /dev/io.


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