From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Samudrala, Sridhar" Subject: Re: [PATCH net-next 1/2] virtio_net: Introduce VIRTIO_NET_F_MASTER feature bit Date: Wed, 3 Jan 2018 10:17:50 -0800 Message-ID: <14a13fdd-94b3-57ea-1c4b-ca3df0ca8232@intel.com> References: <1514939738-22423-1-git-send-email-sridhar.samudrala@intel.com> <1514939738-22423-2-git-send-email-sridhar.samudrala@intel.com> <20180103191101-mutt-send-email-mst@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 8bit Cc: stephen@networkplumber.org, netdev@vger.kernel.org, virtualization@lists.linux-foundation.org, virtio-dev@lists.oasis-open.org, jesse.brandeburg@intel.com To: "Michael S. Tsirkin" Return-path: Received: from mga03.intel.com ([134.134.136.65]:57638 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751204AbeACSRv (ORCPT ); Wed, 3 Jan 2018 13:17:51 -0500 In-Reply-To: <20180103191101-mutt-send-email-mst@kernel.org> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 1/3/2018 9:43 AM, Michael S. Tsirkin wrote: > On Tue, Jan 02, 2018 at 04:35:37PM -0800, Sridhar Samudrala wrote: >> This feature bit can be used by hypervisor to indicate virtio_net device to >> act as a master for a directly attached passthru device with the same MAC >> address. >> >> Signed-off-by: Sridhar Samudrala >> --- >> drivers/net/virtio_net.c | 3 ++- >> include/uapi/linux/virtio_net.h | 1 + >> 2 files changed, 3 insertions(+), 1 deletion(-) >> >> diff --git a/drivers/net/virtio_net.c b/drivers/net/virtio_net.c >> index 6fb7b658a6cc..46844a1d9a62 100644 >> --- a/drivers/net/virtio_net.c >> +++ b/drivers/net/virtio_net.c >> @@ -2796,7 +2796,8 @@ static struct virtio_device_id id_table[] = { >> VIRTIO_NET_F_CTRL_RX, VIRTIO_NET_F_CTRL_VLAN, \ >> VIRTIO_NET_F_GUEST_ANNOUNCE, VIRTIO_NET_F_MQ, \ >> VIRTIO_NET_F_CTRL_MAC_ADDR, \ >> - VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS >> + VIRTIO_NET_F_MTU, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, \ >> + VIRTIO_NET_F_MASTER >> >> static unsigned int features[] = { >> VIRTNET_FEATURES, >> diff --git a/include/uapi/linux/virtio_net.h b/include/uapi/linux/virtio_net.h >> index fc353b518288..a9b4e0836786 100644 >> --- a/include/uapi/linux/virtio_net.h >> +++ b/include/uapi/linux/virtio_net.h >> @@ -56,6 +56,7 @@ >> #define VIRTIO_NET_F_MQ 22 /* Device supports Receive Flow >> * Steering */ >> #define VIRTIO_NET_F_CTRL_MAC_ADDR 23 /* Set MAC address */ >> +#define VIRTIO_NET_F_MASTER 62 /* act as master for a VF device */ > Well the virtio hardware doesn't really know whether it's a master or > the slave of a bond. In fact quite possibly down the road we'll add a > virtual device on top as others seem to want to do - that other one will > be the master then. > > And we do nothing do check it's a VF. > > So maybe a better name would be > > #define VIRTIO_NET_F_BACKUP 62 /* Act as backup for another device with the same MAC */ Yes. BACKUP  does make more sense as virtio is only used as a BACKUP datapath when the other device is unplugged. > >> >> #ifndef VIRTIO_NET_NO_LEGACY >> #define VIRTIO_NET_F_GSO 6 /* Host handles pkts w/ any GSO type */ >> -- >> 2.14.3