Re: [PATCH] virtio-net: put virtio net header inline with data

From: Rusty Russell <rusty@rustcorp.com.au>
To: "Michael S. Tsirkin" <mst@redhat.com>, netdev@vger.kernel.org
Cc: Cong Wang <amwang@redhat.com>,
	linux-kernel@vger.kernel.org,
	virtualization@lists.linux-foundation.org,
	Dave Jones <davej@redhat.com>,
	"David S. Miller" <davem@davemloft.net>
Subject: Re: [PATCH] virtio-net: put virtio net header inline with data
Date: Tue, 09 Jul 2013 11:46:23 +0930	[thread overview]
Message-ID: <871u78eavc.fsf@rustcorp.com.au> (raw)
In-Reply-To: <20130708101259.GA16074@redhat.com>

"Michael S. Tsirkin" <mst@redhat.com> writes:
> For small packets we can simplify xmit processing
> by linearizing buffers with the header:
> most packets seem to have enough head room
> we can use for this purpose.
> Since existing hypervisors require that header
> is the first s/g element, we need a feature bit
> for this.
>
> Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
> ---
>
> Note: this needs to be applied on top of patch
> defining VIRTIO_F_ANY_LAYOUT - bit to be
> selected by Rusty.
>
> The following patch should work for any definition of
> VIRTIO_F_ANY_LAYOUT - I used bit 31 for testing.
> Rusty, could you please pick a valid bit for VIRTIO_F_ANY_LAYOUT
> and squeeze this patch into 3.11?

Sorry, it's too late.

First, I've been a bit lax in sending patches via DaveM, and this is
definitely his territory (ie. more net than virtio).

Secondly, it needs baking and testing time.

Cheers,
Rusty.