From mboxrd@z Thu Jan  1 00:00:00 1970
From: Laszlo Ersek <lersek@redhat.com>
Subject: Re: Features and bug-fixes that went in Linux 3.2
Date: Thu, 12 Jan 2012 18:02:46 +0100
Message-ID: <4F0F1236.6010705@redhat.com>
References: <20120109213039.GC4773@phenom.dumpdata.com>	<6035A0D088A63A46850C3988ED045A4B09AFCB@BITCOM1.int.sbss.com.au>
	<1326148662.29084.77.camel@dagon.hellion.org.uk>
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii"; Format="flowed"
Content-Transfer-Encoding: 7bit
Return-path: <xen-devel-bounces@lists.xensource.com>
In-Reply-To: <1326148662.29084.77.camel@dagon.hellion.org.uk>
List-Unsubscribe: <http://lists.xensource.com/mailman/options/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/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: Ian Campbell <Ian.Campbell@citrix.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>, James Harper <james.harper@bendigoit.com.au>, "xen-devel@lists.xensource.com" <xen-devel@lists.xensource.com>, Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>, "xen-users@lists.xensource.com" <xen-users@lists.xensource.com>
List-Id: xen-devel@lists.xenproject.org

On 01/09/12 23:37, Ian Campbell wrote:
> On Mon, 2012-01-09 at 22:26 +0000, James Harper wrote:
>>>   - Initial work laid out for netback page-flipping (also called zero-copying).
>>
>> Isn't this how it used to work originally?
>
> Some of the original infrastructure for doing this was not upstreamable
> (the PageForeign stuff) so while upstream netback I decided to go with a
> simpler/less-intrusive copying mode so we could have some sort of
> networking support in mainline.
>
> I've been working on re-laying the necessary infrastructure to allow for
> page flipping/mapping mode in upstream (as well as fixing another
> generic class of bug) -- you can see the "skb frag destructor" patches
> on the netdev list.

(Ultimately I found it here:

     http://lwn.net/Articles/474791/

.)

Ian, do you think the NFS fix in

     http://article.gmane.org/gmane.linux.nfs/45955

for problem

     http://marc.info/?l=linux-nfs&m=122424132729720&w=2

would be technically feasible to port to 2.6.18, based on the existing 
PageForeign stuff instead of parts 1-5 of the series?

Thanks
Laszlo