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[V5,3/4] virtio-net: notify guest to annouce itself

Message ID 20120316085511.4947.14490.stgit@amd-6168-8-1.englab.nay.redhat.com
State New
Headers show

Commit Message

Jason Wang March 16, 2012, 8:55 a.m. UTC 
It's hard to track all mac addresses and their usage (vlan, bondings,
ipv6) in qemu to send proper gratuitous packet. The better choice is
to let guest to send them.

So, this patch introduces a new rw config status bit of virtio-net,
VIRTIO_NET_S_ANNOUNCE which is used to notify guest to announce
presence of its link through config update interrupt. When gust have
done the announcement, it should clear that bit. The feature is negotiated by
a new feature bit VIRTIO_NET_F_ANNOUNCE.

Signed-off-by: Jason Wang <jasowang@redhat.com>
---
 hw/virtio-net.c |   19 +++++++++++++++++++
 hw/virtio-net.h |    3 +++
 2 files changed, 22 insertions(+), 0 deletions(-)
diff mbox

Patch

diff --git a/hw/virtio-net.c b/hw/virtio-net.c
index bc5e3a8..c1dbd49 100644
--- a/hw/virtio-net.c
+++ b/hw/virtio-net.c
@@ -95,6 +95,10 @@  static void virtio_net_set_config(VirtIODevice *vdev, const uint8_t *config)
         memcpy(n->mac, netcfg.mac, ETH_ALEN);
         qemu_format_nic_info_str(&n->nic->nc, n->mac);
     }
+
+    /* ignore write to RO byte */
+    memcpy((uint8_t *)&n->status + 1, (uint8_t *)&netcfg.status + 1,
+           sizeof(uint8_t));
 }
 
 static bool virtio_net_started(VirtIONet *n, uint8_t status)
@@ -983,6 +987,20 @@  static void virtio_net_cleanup(VLANClientState *nc)
     n->nic = NULL;
 }
 
+static int virtio_net_announce(VLANClientState *nc)
+{
+    VirtIONet *n = DO_UPCAST(NICState, nc, nc)->opaque;
+
+    if (n->vdev.guest_features & (0x1 << VIRTIO_NET_F_GUEST_ANNOUNCE)
+        && virtio_net_started(n, n->vdev.status)) {
+        n->status |= VIRTIO_NET_S_ANNOUNCE;
+        virtio_notify_config(&n->vdev);
+        return 0;
+    }
+
+    return -1;
+}
+
 static NetClientInfo net_virtio_info = {
     .type = NET_CLIENT_TYPE_NIC,
     .size = sizeof(NICState),
@@ -990,6 +1008,7 @@  static NetClientInfo net_virtio_info = {
     .receive = virtio_net_receive,
         .cleanup = virtio_net_cleanup,
     .link_status_changed = virtio_net_set_link_status,
+    .announce = virtio_net_announce,
 };
 
 VirtIODevice *virtio_net_init(DeviceState *dev, NICConf *conf,
diff --git a/hw/virtio-net.h b/hw/virtio-net.h
index 4468741..f3acbd1 100644
--- a/hw/virtio-net.h
+++ b/hw/virtio-net.h
@@ -44,8 +44,10 @@ 
 #define VIRTIO_NET_F_CTRL_RX    18      /* Control channel RX mode support */
 #define VIRTIO_NET_F_CTRL_VLAN  19      /* Control channel VLAN filtering */
 #define VIRTIO_NET_F_CTRL_RX_EXTRA 20   /* Extra RX mode control support */
+#define VIRTIO_NET_F_GUEST_ANNOUNCE 21  /* Guest can announce itself */
 
 #define VIRTIO_NET_S_LINK_UP    1       /* Link is up */
+#define VIRTIO_NET_S_ANNOUNCE   0x100   /* Announcement is needed */
 
 #define TX_TIMER_INTERVAL 150000 /* 150 us */
 
@@ -176,6 +178,7 @@  struct virtio_net_ctrl_mac {
         DEFINE_PROP_BIT("guest_tso6", _state, _field, VIRTIO_NET_F_GUEST_TSO6, true), \
         DEFINE_PROP_BIT("guest_ecn", _state, _field, VIRTIO_NET_F_GUEST_ECN, true), \
         DEFINE_PROP_BIT("guest_ufo", _state, _field, VIRTIO_NET_F_GUEST_UFO, true), \
+        DEFINE_PROP_BIT("guest_announce", _state, _field, VIRTIO_NET_F_GUEST_ANNOUNCE, true), \
         DEFINE_PROP_BIT("host_tso4", _state, _field, VIRTIO_NET_F_HOST_TSO4, true), \
         DEFINE_PROP_BIT("host_tso6", _state, _field, VIRTIO_NET_F_HOST_TSO6, true), \
         DEFINE_PROP_BIT("host_ecn", _state, _field, VIRTIO_NET_F_HOST_ECN, true), \