From mboxrd@z Thu Jan  1 00:00:00 1970
From: Christoph Egger <Christoph.Egger@amd.com>
Subject: Re: [PATCH][TOOLS] libxc: mmap fixes for BSD
Date: Tue, 10 Jun 2008 16:37:24 +0200
Message-ID: <200806101637.25049.Christoph.Egger@amd.com>
References: <C4744C94.21E33%keir.fraser@eu.citrix.com>
Mime-Version: 1.0
Content-Type: text/plain;
  charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
Return-path: <xen-devel-bounces@lists.xensource.com>
In-Reply-To: <C4744C94.21E33%keir.fraser@eu.citrix.com>
Content-Disposition: inline
List-Unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
List-Post: <mailto:xen-devel@lists.xensource.com>
List-Help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-Subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>,
	<mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
Sender: xen-devel-bounces@lists.xensource.com
Errors-To: xen-devel-bounces@lists.xensource.com
To: xen-devel@lists.xensource.com
Cc: Keir Fraser <keir.fraser@eu.citrix.com>
List-Id: xen-devel@lists.xenproject.org

On Tuesday 10 June 2008 16:21:56 Keir Fraser wrote:
> On 10/6/08 15:09, "Christoph Egger" <Christoph.Egger@amd.com> wrote:
> > On BSD, mmap()ing files works on on-disk files but not on
> > pseudo filesystems like kernfs or procfs.
> > Therefore, attached patch mmap()s anonymous memory.
> >
> > Linux equivalents are sysfs and procfs to above BSD's pseudo-filesystem=
s.
> > On Linux, mmap is implemented for sysfs but it is questionable to me
> > how write operations work since (most) files in sysfs have
> > static content. So this patch may fix some problems
> > with a Linux Dom0, too.
>
> We can hide special setup in mmap(/proc/xen/privcmd) that is necessary for
> later foreign mapping operations. Perhaps xc_map_foreign_ranges() interfa=
ce
> could be changed so that it does the mmap(), then fills in the .va field =
in
> the array of entries that it is passed, and finally return the address it
> got from mmap()?
>
> This would make xc_map_foreign_ranges() similar to our other xc_map*()
> functions, which all hide the mmap() invocation inside their
> implementation.

That's fine with me.

Christoph

=2D-=20
AMD Saxony, Dresden, Germany
Operating System Research Center

Legal Information:
AMD Saxony Limited Liability Company & Co. KG
Sitz (Gesch=E4ftsanschrift):
   Wilschdorfer Landstr. 101, 01109 Dresden, Deutschland
Registergericht Dresden: HRA 4896
vertretungsberechtigter Komplement=E4r:
   AMD Saxony LLC (Sitz Wilmington, Delaware, USA)
Gesch=E4ftsf=FChrer der AMD Saxony LLC:
   Dr. Hans-R. Deppe, Thomas McCoy