From: Alexander Duyck <aduyck@mirantis.com>
Date: Wed, 9 Mar 2016 17:24:23 +0000 (-0800)
Subject: gro: Defer clearing of flush bit in tunnel paths
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=c194cf93c164ed1c71142485ee0f70f9f2d1fe35;p=openwrt%2Fstaging%2Fblogic.git

gro: Defer clearing of flush bit in tunnel paths

This patch updates the GRO handlers for GRE, VXLAN, GENEVE, and FOU so that
we do not clear the flush bit until after we have called the next level GRO
handler.  Previously this was being cleared before parsing through the list
of frames, however this resulted in several paths where either the bit
needed to be reset but wasn't as in the case of FOU, or cases where it was
being set as in GENEVE.  By just deferring the clearing of the bit until
after the next level protocol has been parsed we can avoid any unnecessary
bit twiddling and avoid bugs.

Signed-off-by: Alexander Duyck <aduyck@mirantis.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/geneve.c b/drivers/net/geneve.c
index 33185b9a435e..192631a345df 100644
--- a/drivers/net/geneve.c
+++ b/drivers/net/geneve.c
@@ -463,8 +463,6 @@ static struct sk_buff **geneve_gro_receive(struct sk_buff **head,
 			goto out;
 	}
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		if (!NAPI_GRO_CB(p)->same_flow)
 			continue;
@@ -481,14 +479,13 @@ static struct sk_buff **geneve_gro_receive(struct sk_buff **head,
 
 	rcu_read_lock();
 	ptype = gro_find_receive_by_type(type);
-	if (!ptype) {
-		flush = 1;
+	if (!ptype)
 		goto out_unlock;
-	}
 
 	skb_gro_pull(skb, gh_len);
 	skb_gro_postpull_rcsum(skb, gh, gh_len);
 	pp = ptype->callbacks.gro_receive(head, skb);
+	flush = 0;
 
 out_unlock:
 	rcu_read_unlock();
diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 8eda76f9e474..800106a7246c 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -591,8 +591,6 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head,
 
 	skb_gro_pull(skb, sizeof(struct vxlanhdr)); /* pull vxlan header */
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		if (!NAPI_GRO_CB(p)->same_flow)
 			continue;
@@ -606,6 +604,7 @@ static struct sk_buff **vxlan_gro_receive(struct sk_buff **head,
 	}
 
 	pp = eth_gro_receive(head, skb);
+	flush = 0;
 
 out:
 	skb_gro_remcsum_cleanup(skb, &grc);
diff --git a/net/ipv4/fou.c b/net/ipv4/fou.c
index 88dab0c1670c..780484243e14 100644
--- a/net/ipv4/fou.c
+++ b/net/ipv4/fou.c
@@ -319,8 +319,6 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
 
 	skb_gro_pull(skb, hdrlen);
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		const struct guehdr *guehdr2;
 
@@ -352,6 +350,7 @@ static struct sk_buff **gue_gro_receive(struct sk_buff **head,
 		goto out_unlock;
 
 	pp = ops->callbacks.gro_receive(head, skb);
+	flush = 0;
 
 out_unlock:
 	rcu_read_unlock();
diff --git a/net/ipv4/gre_offload.c b/net/ipv4/gre_offload.c
index 47f4c544c916..540866dbd27d 100644
--- a/net/ipv4/gre_offload.c
+++ b/net/ipv4/gre_offload.c
@@ -175,8 +175,6 @@ static struct sk_buff **gre_gro_receive(struct sk_buff **head,
 					     null_compute_pseudo);
 	}
 
-	flush = 0;
-
 	for (p = *head; p; p = p->next) {
 		const struct gre_base_hdr *greh2;
 
@@ -213,6 +211,7 @@ static struct sk_buff **gre_gro_receive(struct sk_buff **head,
 	skb_gro_postpull_rcsum(skb, greh, grehlen);
 
 	pp = ptype->callbacks.gro_receive(head, skb);
+	flush = 0;
 
 out_unlock:
 	rcu_read_unlock();