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Date: Tue, 16 May 2006 01:24:06 -0700
From: Maxim Sobolev <sobomax@FreeBSD.ORG>
To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Cc: "current@freebsd.org" <current@FreeBSD.ORG>
Subject: Re: Optional mmap(2) support for geom(4) providers
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On Tue, May 16, 2006 at 07:40:36AM +0200, Poul-Henning Kamp wrote:
> In message <4468DC05.9080808@sippysoft.com>, Maxim Sobolev writes:
> >Poul-Henning Kamp wrote:
> >> In message <44681D92.80309@sippysoft.com>, Maxim Sobolev writes:
> >>> Hi,
> >>>
> >>> I would like to extend md(4) with support for mmap(4) operations, 
> >> 
> >> Uhm, how exactly would that work ?
> >
> >Just like ioctl(2) works: geom_dev will accept mmap requests and pass it 
> >to the underlying provider for execution if that provider has mmap 
> >handler in its g_class.
> 
> No, I meant: how will you use this ?

Well, in my particular case I would like to experiment with
dynamic exporting of shared ELF objects from the kernel into
userspace. md(4) seems like a good fit, but dlopen(3) uses
mmap, so that it doesn't work OOB. There can be other uses
as well.

-Maxim