+
+ ovs_lock();
+ dp = get_dp(sock_net(skb->sk), ovs_header->dp_ifindex);
+ if (unlikely(!dp)) {
+ error = -ENODEV;
+ goto err_unlock_ovs;
+ }
+ /* Check that the flow exists. */
+ flow = ovs_flow_tbl_lookup(&dp->table, &key);
+ if (unlikely(!flow)) {
+ error = -ENOENT;
+ goto err_unlock_ovs;
+ }
+ /* The unmasked key has to be the same for flow updates. */
+ if (unlikely(!ovs_flow_cmp_unmasked_key(flow, &match))) {
+ error = -EEXIST;
+ goto err_unlock_ovs;
+ }
+ /* Update actions, if present. */
+ if (likely(acts)) {
+ old_acts = ovsl_dereference(flow->sf_acts);
+ rcu_assign_pointer(flow->sf_acts, acts);
+
+ if (unlikely(reply)) {
+ error = ovs_flow_cmd_fill_info(flow,
+ ovs_header->dp_ifindex,
+ reply, info->snd_portid,
+ info->snd_seq, 0,
+ OVS_FLOW_CMD_NEW);
+ BUG_ON(error < 0);
+ }
+ } else {
+ /* Could not alloc without acts before locking. */
+ reply = ovs_flow_cmd_build_info(flow, ovs_header->dp_ifindex,
+ info, OVS_FLOW_CMD_NEW, false);
+ if (unlikely(IS_ERR(reply))) {
+ error = PTR_ERR(reply);
+ goto err_unlock_ovs;
+ }
+ }
+
+ /* Clear stats. */
+ if (a[OVS_FLOW_ATTR_CLEAR])
+ ovs_flow_stats_clear(flow);