net sched filters: pass netlink message flags in event notification

Userland client should be able to read an event, and reflect it back to
the kernel, therefore it needs to extract complete set of netlink flags.

For example, this will allow "tc monitor" to distinguish Add and Replace
operations.
Signed-off-by: NRoman Mashak <mrv@mojatatu.com>
Signed-off-by: NJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/sched/cls_api.c

@@ -112,7 +112,7 @@ static void tfilter_notify_chain(struct net *net, struct sk_buff *oskb,
 
 	for (it_chain = chain; (tp = rtnl_dereference(*it_chain)) != NULL;
 	     it_chain = &tp->next)
-		tfilter_notify(net, oskb, n, tp, 0, event, false);
+		tfilter_notify(net, oskb, n, tp, n->nlmsg_flags, event, false);
 }
 
 /* Select new prio value from the range, managed by kernel. */
@@ -430,7 +430,8 @@ static int tfilter_notify(struct net *net, struct sk_buff *oskb,
 	if (!skb)
 		return -ENOBUFS;
 
-	if (tcf_fill_node(net, skb, tp, fh, portid, n->nlmsg_seq, 0, event) <= 0) {
+	if (tcf_fill_node(net, skb, tp, fh, portid, n->nlmsg_seq,
+			  n->nlmsg_flags, event) <= 0) {
 		kfree_skb(skb);
 		return -EINVAL;
 	}