snmp: add missing counters for RFC 4293

The IP MIB (RFC 4293) defines stats for InOctets, OutOctets, InMcastOctets and
OutMcastOctets:
http://tools.ietf.org/html/rfc4293
But it seems we don't track those in any way that easy to separate from other
protocols.  This patch adds those missing counters to the stats file. Tested
successfully by me

With help from Eric Dumazet.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/mcast.c b/net/ipv6/mcast.c
index a51fb33..4b48819 100644
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -1449,7 +1449,8 @@
 	int err;
 	struct flowi fl;
 
-	IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTREQUESTS);
+	IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUT, skb->len);
+
 	payload_len = (skb->tail - skb->network_header) - sizeof(*pip6);
 	mldlen = skb->tail - skb->transport_header;
 	pip6->payload_len = htons(payload_len);
@@ -1473,13 +1474,15 @@
 	if (err)
 		goto err_out;
 
+	payload_len = skb->len;
+
 	err = NF_HOOK(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, skb->dev,
 		      dst_output);
 out:
 	if (!err) {
 		ICMP6MSGOUT_INC_STATS_BH(net, idev, ICMPV6_MLD2_REPORT);
 		ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTMSGS);
-		IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_OUTMCASTPKTS);
+		IP6_UPD_PO_STATS_BH(net, idev, IPSTATS_MIB_OUTMCAST, payload_len);
 	} else
 		IP6_INC_STATS_BH(net, idev, IPSTATS_MIB_OUTDISCARDS);
 
@@ -1773,10 +1776,6 @@
 		     IPV6_TLV_PADN, 0 };
 	struct flowi fl;
 
-	rcu_read_lock();
-	IP6_INC_STATS(net, __in6_dev_get(dev),
-		      IPSTATS_MIB_OUTREQUESTS);
-	rcu_read_unlock();
 	if (type == ICMPV6_MGM_REDUCTION)
 		snd_addr = &in6addr_linklocal_allrouters;
 	else
@@ -1786,6 +1785,11 @@
 	payload_len = len + sizeof(ra);
 	full_len = sizeof(struct ipv6hdr) + payload_len;
 
+	rcu_read_lock();
+	IP6_UPD_PO_STATS(net, __in6_dev_get(dev),
+		      IPSTATS_MIB_OUT, full_len);
+	rcu_read_unlock();
+
 	skb = sock_alloc_send_skb(sk, LL_ALLOCATED_SPACE(dev) + full_len, 1, &err);
 
 	if (skb == NULL) {
@@ -1838,13 +1842,14 @@
 	if (err)
 		goto err_out;
 
+
 	err = NF_HOOK(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, skb->dev,
 		      dst_output);
 out:
 	if (!err) {
 		ICMP6MSGOUT_INC_STATS(net, idev, type);
 		ICMP6_INC_STATS(net, idev, ICMP6_MIB_OUTMSGS);
-		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTMCASTPKTS);
+		IP6_UPD_PO_STATS(net, idev, IPSTATS_MIB_OUTMCAST, full_len);
 	} else
 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);