From: Gao Feng <gfree.wind@gmail.com>
Date: Mon, 21 Nov 2016 23:00:32 +0800
Subject: batman-adv: Treat NET_XMIT_CN as transmit successfully

The tc could return NET_XMIT_CN as one congestion notification, but
it does not mean the packet is lost. Other modules like ipvlan,
macvlan, and others treat NET_XMIT_CN as success too.

So batman-adv should add the NET_XMIT_CN check.

Signed-off-by: Gao Feng <gfree.wind@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>

Origin: upstream, https://git.open-mesh.org/batman-adv.git/commit/1120b81c74187f489c08fc9438305071def089cc

diff --git a/net/batman-adv/distributed-arp-table.c b/net/batman-adv/distributed-arp-table.c
index 49576c5a3fe306a42c28c3901d2b2c6cce7d0b8e..3641765d55df049a5dbac35d322ebc537a0f0322 100644
--- a/net/batman-adv/distributed-arp-table.c
+++ b/net/batman-adv/distributed-arp-table.c
@@ -659,7 +659,8 @@ static bool batadv_dat_send_data(struct batadv_priv *bat_priv,
 		}
 
 		send_status = batadv_send_unicast_skb(tmp_skb, neigh_node);
-		if (send_status == NET_XMIT_SUCCESS) {
+		if (send_status == NET_XMIT_SUCCESS ||
+		    send_status == NET_XMIT_CN) {
 			/* count the sent packet */
 			switch (packet_subtype) {
 			case BATADV_P_DAT_DHT_GET:
diff --git a/net/batman-adv/fragmentation.c b/net/batman-adv/fragmentation.c
index 11149e5be4e0ef9dfe2872e1d8d1f6dbb4ccdb14..d33f16b9b8ac13ba630bf9ac8c5f4f0ca79fc878 100644
--- a/net/batman-adv/fragmentation.c
+++ b/net/batman-adv/fragmentation.c
@@ -517,7 +517,7 @@ int batadv_frag_send_packet(struct sk_buff *skb,
 		batadv_add_counter(bat_priv, BATADV_CNT_FRAG_TX_BYTES,
 				   skb_fragment->len + ETH_HLEN);
 		ret = batadv_send_unicast_skb(skb_fragment, neigh_node);
-		if (ret != NET_XMIT_SUCCESS) {
+		if (ret != NET_XMIT_SUCCESS && ret != NET_XMIT_CN) {
 			ret = NET_XMIT_DROP;
 			goto put_primary_if;
 		}
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index 6713bdf414cdacdaf36ecd6ac516f99e079fb51e..6b08b26da4d94be9c8c5e9dc708ddc18d8282428 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -262,7 +262,7 @@ static int batadv_recv_my_icmp_packet(struct batadv_priv *bat_priv,
 		icmph->ttl = BATADV_TTL;
 
 		res = batadv_send_skb_to_orig(skb, orig_node, NULL);
-		if (res == NET_XMIT_SUCCESS)
+		if (res == NET_XMIT_SUCCESS || res == NET_XMIT_CN)
 			ret = NET_RX_SUCCESS;
 
 		/* skb was consumed */
@@ -330,7 +330,7 @@ static int batadv_recv_icmp_ttl_exceeded(struct batadv_priv *bat_priv,
 	icmp_packet->ttl = BATADV_TTL;
 
 	res = batadv_send_skb_to_orig(skb, orig_node, NULL);
-	if (res == NET_RX_SUCCESS)
+	if (res == NET_RX_SUCCESS || res == NET_XMIT_CN)
 		ret = NET_XMIT_SUCCESS;
 
 	/* skb was consumed */
@@ -424,7 +424,7 @@ int batadv_recv_icmp_packet(struct sk_buff *skb,
 
 	/* route it */
 	res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
-	if (res == NET_XMIT_SUCCESS)
+	if (res == NET_XMIT_SUCCESS || res == NET_XMIT_CN)
 		ret = NET_RX_SUCCESS;
 
 	/* skb was consumed */
@@ -719,14 +719,14 @@ static int batadv_route_unicast_packet(struct sk_buff *skb,
 
 	len = skb->len;
 	res = batadv_send_skb_to_orig(skb, orig_node, recv_if);
-	if (res == NET_XMIT_SUCCESS)
+	if (res == NET_XMIT_SUCCESS || res == NET_XMIT_CN)
 		ret = NET_RX_SUCCESS;
 
 	/* skb was consumed */
 	skb = NULL;
 
 	/* translate transmit result into receive result */
-	if (res == NET_XMIT_SUCCESS) {
+	if (res == NET_XMIT_SUCCESS || res == NET_XMIT_CN) {
 		/* skb was transmitted and consumed */
 		batadv_inc_counter(bat_priv, BATADV_CNT_FORWARD);
 		batadv_add_counter(bat_priv, BATADV_CNT_FORWARD_BYTES,
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 7b3494ae6ad93fd0d32391e5c88f5d636f43acd5..60516bbb7e8391f3063ba1e48c81288ffc7bef49 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -386,7 +386,7 @@ send:
 			ret = batadv_send_skb_via_tt(bat_priv, skb, dst_hint,
 						     vid);
 		}
-		if (ret != NET_XMIT_SUCCESS)
+		if (ret != NET_XMIT_SUCCESS && ret != NET_XMIT_CN)
 			goto dropped_freed;
 	}
 
diff --git a/net/batman-adv/tp_meter.c b/net/batman-adv/tp_meter.c
index 981e8c5b07e9398c68df711d1d7b54e6e9333ead..c367c8316a822c70ee397bbe1266cd38f24a279b 100644
--- a/net/batman-adv/tp_meter.c
+++ b/net/batman-adv/tp_meter.c
@@ -615,7 +615,7 @@ static int batadv_tp_send_msg(struct batadv_tp_vars *tp_vars, const u8 *src,
 	batadv_tp_fill_prerandom(tp_vars, data, data_len);
 
 	r = batadv_send_skb_to_orig(skb, orig_node, NULL);
-	if (r == NET_XMIT_SUCCESS)
+	if (r == NET_XMIT_SUCCESS || r == NET_XMIT_CN)
 		return 0;
 
 	return BATADV_TP_REASON_CANT_SEND;