vdpa: Restore vlan filtering state

This patch introduces vhost_vdpa_net_load_single_vlan()
and vhost_vdpa_net_load_vlan() to restore the vlan
filtering state at device's startup.

Co-developed-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Eugenio Pérez <eperezma@redhat.com>
Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
Message-Id: <e76a29f77bb3f386e4a643c8af94b77b775d1752.1690106284.git.yin31149@gmail.com>
Tested-by: Lei Yang <leiyang@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

net/vhost-vdpa.c

@@ -968,6 +968,50 @@ static int vhost_vdpa_net_load_rx(VhostVDPAState *s,
     return 0;
 }
 
+static int vhost_vdpa_net_load_single_vlan(VhostVDPAState *s,
+                                           const VirtIONet *n,
+                                           uint16_t vid)
+{
+    const struct iovec data = {
+        .iov_base = &vid,
+        .iov_len = sizeof(vid),
+    };
+    ssize_t dev_written = vhost_vdpa_net_load_cmd(s, VIRTIO_NET_CTRL_VLAN,
+                                                  VIRTIO_NET_CTRL_VLAN_ADD,
+                                                  &data, 1);
+    if (unlikely(dev_written < 0)) {
+        return dev_written;
+    }
+    if (unlikely(*s->status != VIRTIO_NET_OK)) {
+        return -EIO;
+    }
+
+    return 0;
+}
+
+static int vhost_vdpa_net_load_vlan(VhostVDPAState *s,
+                                    const VirtIONet *n)
+{
+    int r;
+
+    if (!virtio_vdev_has_feature(&n->parent_obj, VIRTIO_NET_F_CTRL_VLAN)) {
+        return 0;
+    }
+
+    for (int i = 0; i < MAX_VLAN >> 5; i++) {
+        for (int j = 0; n->vlans[i] && j <= 0x1f; j++) {
+            if (n->vlans[i] & (1U << j)) {
+                r = vhost_vdpa_net_load_single_vlan(s, n, (i << 5) + j);
+                if (unlikely(r != 0)) {
+                    return r;
+                }
+            }
+        }
+    }
+
+    return 0;
+}
+
 static int vhost_vdpa_net_load(NetClientState *nc)
 {
     VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
@@ -998,6 +1042,10 @@ static int vhost_vdpa_net_load(NetClientState *nc)
     if (unlikely(r)) {
         return r;
     }
+    r = vhost_vdpa_net_load_vlan(s, n);
+    if (unlikely(r)) {
+        return r;
+    }
 
     return 0;
 }