From owner-freebsd-hackers@FreeBSD.ORG  Sat Dec  3 11:03:37 2011
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To: Filippo Sironi <filippo.sironi@gmail.com>
From: "Poul-Henning Kamp" <phk@phk.freebsd.dk>
In-Reply-To: Your message of "Sat, 03 Dec 2011 11:37:01 +0100."
	<0011FD6A-E29D-4F67-913C-897BA1B2F56F@gmail.com>
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Date: Sat, 03 Dec 2011 11:03:35 +0000
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Cc: freebsd-hackers@freebsd.org
Subject: Re: mmap implementation for cdev
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In message <0011FD6A-E29D-4F67-913C-897BA1B2F56F@gmail.com>, Filippo Sironi wri
tes:
>I need to access the memory both from user space and kernel space, I =
>cannot do that (simply) with an mmap or thread-specific storage if I =
>recall correctly.

Have you looked how shm_open(2) and friends are implemented ?  That
might allow you to.

-- 
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.