From: Justin Pettit <jpettit@nicira.com>
Date: Thu, 26 Jun 2008 06:22:39 +0000 (-0700)
Subject: Fix VLAN modification action in kernel switch.
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=58dc4ead3b2640e155161574e16c2198adb31991;p=openvswitch

Fix VLAN modification action in kernel switch.

A number of errors were uncovered when we actually tried playing with VLAN tags on real traffic.  This fixes endian, sk_buff, and other issues.  Unrelated to VLAN tagging, this also protects some printk calls with net_ratelimit.
---

diff --git a/datapath/datapath.c b/datapath/datapath.c
index 00dbac7c..84036448 100644
--- a/datapath/datapath.c
+++ b/datapath/datapath.c
@@ -443,10 +443,7 @@ static void
 do_port_input(struct net_bridge_port *p, struct sk_buff *skb) 
 {
 	/* Push the Ethernet header back on. */
-	if (skb->protocol == htons(ETH_P_8021Q))
-		skb_push(skb, VLAN_ETH_HLEN);
-	else
-		skb_push(skb, ETH_HLEN);
+	skb_push(skb, ETH_HLEN);
 	fwd_port_input(p->dp->chain, skb, p->port_no);
 }
 
diff --git a/datapath/forward.c b/datapath/forward.c
index 44967203..e0b07011 100644
--- a/datapath/forward.c
+++ b/datapath/forward.c
@@ -87,10 +87,16 @@ void execute_actions(struct datapath *dp, struct sk_buff *skb,
 			max_len = ntohs(a->arg.output.max_len);
 		} else {
 			if (!make_writable(&skb)) {
-				printk("make_writable failed\n");
+				if (net_ratelimit())
+				    printk("make_writable failed\n");
 				break;
 			}
 			skb = execute_setter(skb, eth_proto, key, a);
+			if (!skb) {
+				if (net_ratelimit())
+					printk("execute_setter lost skb\n");
+				return;
+			}
 		}
 	}
 	if (prev_port != -1)
@@ -199,17 +205,23 @@ static struct sk_buff *vlan_pull_tag(struct sk_buff *skb)
 static struct sk_buff *modify_vlan(struct sk_buff *skb, 
 		const struct sw_flow_key *key, const struct ofp_action *a)
 {
-	uint16_t new_id = a->arg.vlan_id;
+	uint16_t new_id = ntohs(a->arg.vlan_id);
 
 	if (new_id != OFP_VLAN_NONE) {
 		if (key->dl_vlan != htons(OFP_VLAN_NONE)) {
 			/* Modify vlan id, but maintain other TCI values */
 			struct vlan_ethhdr *vh = vlan_eth_hdr(skb);
 			vh->h_vlan_TCI = (vh->h_vlan_TCI 
-					& ~(htons(VLAN_VID_MASK))) | htons(new_id);
+					& ~(htons(VLAN_VID_MASK))) | a->arg.vlan_id;
 		} else  {
 			/* Add vlan header */
-			skb = vlan_put_tag(skb, new_id);
+
+			/* xxx The vlan_put_tag function, doesn't seem to work
+			 * xxx reliably when it attempts to use the hardware-accelerated
+			 * xxx version.  We'll directly use the software version
+			 * xxx until the problem can be diagnosed.
+			 */
+			skb = __vlan_put_tag(skb, new_id);
 		}
 	} else  {
 		/* Remove an existing vlan header if it exists */
@@ -603,7 +615,7 @@ make_writable(struct sk_buff **pskb)
 	if (skb_shared(*pskb) || skb_cloned(*pskb))
 		goto copy_skb;
 
-	return pskb_may_pull(*pskb, 64); /* FIXME? */
+	return pskb_may_pull(*pskb, 40); /* FIXME? */
 
 copy_skb:
 	nskb = skb_copy(*pskb, GFP_ATOMIC);