From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:59113) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZkIZQ-00060Y-4n for qemu-devel@nongnu.org; Thu, 08 Oct 2015 17:17:49 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZkIZL-0007II-4u for qemu-devel@nongnu.org; Thu, 08 Oct 2015 17:17:48 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45359) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZkIZK-0007I8-Vi for qemu-devel@nongnu.org; Thu, 08 Oct 2015 17:17:43 -0400 Date: Fri, 9 Oct 2015 00:17:37 +0300 From: "Michael S. Tsirkin" Message-ID: <1444338957-15293-16-git-send-email-mst@redhat.com> References: <1444338957-15293-1-git-send-email-mst@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1444338957-15293-1-git-send-email-mst@redhat.com> Subject: [Qemu-devel] [PULL 15/25] vhost user: add support of live migration List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Peter Maydell , Jason Wang , Thibaut Collet From: Thibaut Collet Some vhost user backends are able to support live migration. To provide this service the following features must be added: 1. Add the VIRTIO_NET_F_GUEST_ANNOUNCE capability to vhost-net when netdev backend is vhost-user. 2. Provide a nop receive callback to vhost-user. This callback is called by: * qemu_announce_self after a migration to send fake RARP to avoid network outage for peers talking to the migrated guest. - For guest with GUEST_ANNOUNCE capabilities, guest already sends GARP when the bit VIRTIO_NET_S_ANNOUNCE is set. => These packets must be discarded. - For guest without GUEST_ANNOUNCE capabilities, migration termination is notified when the guest sends packets. => These packets can be discarded. * virtio_net_tx_bh with a dummy boot to send fake bootp/dhcp request. BIOS guest manages virtio driver to send 4 bootp/dhcp request in case of dummy boot. => These packets must be discarded. Signed-off-by: Thibaut Collet Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- hw/net/vhost_net.c | 2 ++ net/vhost-user.c | 10 ++++++++++ 2 files changed, 12 insertions(+) diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c index 1ab4133..840f443 100644 --- a/hw/net/vhost_net.c +++ b/hw/net/vhost_net.c @@ -85,6 +85,8 @@ static const int user_feature_bits[] = { VIRTIO_NET_F_CTRL_MAC_ADDR, VIRTIO_NET_F_CTRL_GUEST_OFFLOADS, + VIRTIO_NET_F_GUEST_ANNOUNCE, + VIRTIO_NET_F_MQ, VHOST_INVALID_FEATURE_BIT diff --git a/net/vhost-user.c b/net/vhost-user.c index 9b38431..87917a5 100644 --- a/net/vhost-user.c +++ b/net/vhost-user.c @@ -103,6 +103,15 @@ err: return -1; } +static ssize_t vhost_user_receive(NetClientState *nc, const uint8_t *buf, + size_t size) +{ + /* Discard the request that is received and managed by backend + * by an other way. + */ + return size; +} + static void vhost_user_cleanup(NetClientState *nc) { VhostUserState *s = DO_UPCAST(VhostUserState, nc, nc); @@ -132,6 +141,7 @@ static bool vhost_user_has_ufo(NetClientState *nc) static NetClientInfo net_vhost_user_info = { .type = NET_CLIENT_OPTIONS_KIND_VHOST_USER, .size = sizeof(VhostUserState), + .receive = vhost_user_receive, .cleanup = vhost_user_cleanup, .has_vnet_hdr = vhost_user_has_vnet_hdr, .has_ufo = vhost_user_has_ufo, -- MST