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To: John-Mark Gurney <gurney_j@resnet.uoregon.edu>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Tue, 16 May 2006 14:27:07 PDT."
	<20060516212707.GI65555@funkthat.com> 
Date: Tue, 16 May 2006 23:30:33 +0200
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Sender: phk@critter.freebsd.dk
Cc: Maxim Sobolev <sobomax@FreeBSD.ORG>,
	"current@freebsd.org" <current@FreeBSD.ORG>
Subject: Re: Optional mmap(2) support for geom(4) providers 
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In message <20060516212707.GI65555@funkthat.com>, John-Mark Gurney writes:
>Maxim Sobolev wrote this message on Tue, May 16, 2006 at 01:24 -0700:
>> 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.
>
>Doing a seperate cdev that implements mmap is quite easy...
>
>For something like that it seems like you wouldn't need any of md's
>disk device features, would you?

I agree, md(4) will only get in the way of what is necessary.

Look at the adlink driver, it is much closer to what you want.

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk@FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.