Re: [RFC v2] virtio: add virtio-over-PCI driver

From: Ira Snyder <iws@ovro.caltech.edu>
To: Grant Likely <grant.likely@secretlab.ca>
Cc: Arnd Bergmann <arnd@arndb.de>,
	Jan-Bernd Themann <THEMANN@de.ibm.com>,
	netdev@vger.kernel.org, Rusty Russell <rusty@rustcorp.com.au>,
	linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org
Subject: Re: [RFC v2] virtio: add virtio-over-PCI driver
Date: Thu, 11 Jun 2009 08:10:13 -0700	[thread overview]
Message-ID: <20090611151013.GA9323@ovro.caltech.edu> (raw)
In-Reply-To: <fa686aa40906110722y1b4b8c22l7ccdd32d6684324d@mail.gmail.com>

On Thu, Jun 11, 2009 at 08:22:54AM -0600, Grant Likely wrote:
> On Tue, Apr 14, 2009 at 3:53 PM, Ira Snyder<iws@ovro.caltech.edu> wrote:
> > On Tue, Apr 14, 2009 at 02:28:26PM -0600, Grant Likely wrote:
> >> On Mon, Feb 23, 2009 at 6:00 PM, Ira Snyder <iws@ovro.caltech.edu> wrote:
> >> > This adds support to Linux for using virtio between two computers linked by
> >> > a PCI interface. This allows the use of virtio_net to create a familiar,
> >> > fast interface for communication. It should be possible to use other virtio
> >> > devices in the future, but this has not been tested.
> >>
> >> Hey Ira,
> >>
> >> I like this a lot.  I need to do much the same thing on one of my
> >> platforms, so I'm going to use your patch as my starting point.  Have
> >> you made many changes since you posted this version of your patch?
> >> I'd like to collaborate on the development and help to get it
> >> mainlined.
> >>
> >
> > This would be great. I'd really appreciate the help. I haven't had time
> > to make any changes since I last posted the patch. I started work on
> > converting all of the usage of struct vop_loc_* to just use the on-wire
> > structures, but I didn't get very far before other work got in the way.
> >
> >> In my case I've got an MPC5200 as the 'host' and a Xilinx Virtex
> >> (ppc440) as the 'client'.  I intend set aside a region of the Xilinx
> >> Virtex's memory space for the shared queues.  I'm starting work on it
> >> now, and I'll provide you with feedback and/or patches as I make
> >> progress.
> >>
> >
> > I'm looking forward to seeing your implementation. If you have any
> > questions, I'd be happy to attempt to answer them :)
> 
> Hey Ira,
> 
> I've been slowly hacking on your virtio-over-pci stuff.  I've got an
> initial series of cleanup patches which address some of the comments
> from this thread.  Before I send them to you, have you made any
> changes on your end?  They likely won't apply without changes to the
> core code, so I'd like to sync up with you first.
> 

I haven't made any changes to the code since you've last seen it. I've
been busy with other stuff for quite a while now. I can't wait to see
what you've done :)

At least for the use of the 83xx DMA controller, the DMA_SLAVE mode
patch I posted up about a week ago (to the ppcdev list) could make the
DMA setup much simpler. It hasn't been accepted to mainline yet.

Ira