From mboxrd@z Thu Jan 1 00:00:00 1970 From: John Fastabend Subject: Re: [net-next PATCH v2 1/5] net: virtio dynamically disable/enable LRO Date: Tue, 22 Nov 2016 00:16:26 -0800 Message-ID: <5833FEDA.90701@gmail.com> References: <20161120024710.19187.31037.stgit@john-Precision-Tower-5810> <20161120024934.19187.8294.stgit@john-Precision-Tower-5810> <20161122012202-mutt-send-email-mst@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: daniel@iogearbox.net, eric.dumazet@gmail.com, kubakici@wp.pl, shm@cumulusnetworks.com, davem@davemloft.net, alexei.starovoitov@gmail.com, netdev@vger.kernel.org, bblanco@plumgrid.com, john.r.fastabend@intel.com, brouer@redhat.com, tgraf@suug.ch To: "Michael S. Tsirkin" Return-path: Received: from mail-pf0-f195.google.com ([209.85.192.195]:33034 "EHLO mail-pf0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755267AbcKVIQt (ORCPT ); Tue, 22 Nov 2016 03:16:49 -0500 Received: by mail-pf0-f195.google.com with SMTP id 144so941072pfv.0 for ; Tue, 22 Nov 2016 00:16:48 -0800 (PST) In-Reply-To: <20161122012202-mutt-send-email-mst@kernel.org> Sender: netdev-owner@vger.kernel.org List-ID: On 16-11-21 03:23 PM, Michael S. Tsirkin wrote: > On Sat, Nov 19, 2016 at 06:49:34PM -0800, John Fastabend wrote: >> This adds support for dynamically setting the LRO feature flag. The >> message to control guest features in the backend uses the >> CTRL_GUEST_OFFLOADS msg type. >> >> Signed-off-by: John Fastabend >> --- >> drivers/net/virtio_net.c | 45 ++++++++++++++++++++++++++++++++++++++++++++- >> 1 file changed, 44 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c >> index ca5239a..8189e5b 100644 >> --- a/drivers/net/virtio_net.c >> +++ b/drivers/net/virtio_net.c >> @@ -1419,6 +1419,41 @@ static void virtnet_init_settings(struct net_device *dev) >> .set_settings = virtnet_set_settings, >> }; >> >> +static int virtnet_set_features(struct net_device *netdev, >> + netdev_features_t features) >> +{ >> + struct virtnet_info *vi = netdev_priv(netdev); >> + struct virtio_device *vdev = vi->vdev; >> + struct scatterlist sg; >> + u64 offloads = 0; >> + >> + if (features & NETIF_F_LRO) >> + offloads |= (1 << VIRTIO_NET_F_GUEST_TSO4) | >> + (1 << VIRTIO_NET_F_GUEST_TSO6); >> + >> + if (features & NETIF_F_RXCSUM) >> + offloads |= (1 << VIRTIO_NET_F_GUEST_CSUM); >> + >> + if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS)) { >> + sg_init_one(&sg, &offloads, sizeof(uint64_t)); >> + if (!virtnet_send_command(vi, >> + VIRTIO_NET_CTRL_GUEST_OFFLOADS, >> + VIRTIO_NET_CTRL_GUEST_OFFLOADS_SET, >> + &sg)) { >> + dev_warn(&netdev->dev, >> + "Failed to set guest offloads by virtnet command.\n"); >> + return -EINVAL; >> + } >> + } else if (virtio_has_feature(vdev, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS) && >> + !virtio_has_feature(vdev, VIRTIO_F_VERSION_1)) { >> + dev_warn(&netdev->dev, >> + "No support for setting offloads pre version_1.\n"); >> + return -EINVAL; >> + } > > I don't get this last warning. VIRTIO_NET_F_CTRL_GUEST_OFFLOADS > was exposes by legacy devices, I don't think it's related to > VIRTIO_F_VERSION_1. > OK looks like I can just drop the else if branch here. Thanks, John