From: Steven Smith <ssmith@weybridge.uk.xensource.com>
Date: Tue, 30 Jun 2009 11:55:47 +0000 (+0100)
Subject: patch bonding-vlan-fixes.patch
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=2bc3b0932c9b8df62945acd44e212d24e3fdb63b;p=people%2Fssmith%2Fnc2-2.6.27.git

patch bonding-vlan-fixes.patch
---

diff --git a/net/core/dev.c b/net/core/dev.c
index 024d008f..c2e59c5e 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -88,6 +88,7 @@
 #include <linux/errno.h>
 #include <linux/interrupt.h>
 #include <linux/if_ether.h>
+#include <linux/if_vlan.h>
 #include <linux/netdevice.h>
 #include <linux/etherdevice.h>
 #include <linux/ethtool.h>
@@ -2043,6 +2044,8 @@ int netif_rx_ni(struct sk_buff *skb)
 
 EXPORT_SYMBOL(netif_rx_ni);
 
+#include <../drivers/net/bonding/bonding.h>
+
 static void net_tx_action(struct softirq_action *h)
 {
 	struct softnet_data *sd = &__get_cpu_var(softnet_data);
@@ -2336,8 +2339,45 @@ int netif_receive_skb(struct sk_buff *skb)
 	if (orig_dev->master) {
 		if (skb_bond_should_drop(skb))
 			null_or_orig = orig_dev; /* deliver only exact match */
-		else
+		else {
 			skb->dev = orig_dev->master;
+
+			/* The bonding driver claims to support rx vlan h/w acceleration.
+			 * It actually just assumes the slave supports it and offloads the
+			 * the responsibility for the acceleration to the slave.
+			 * If the slave does not support rx vlan h/w acceleration
+			 * then the tagged frames will end up here.
+			 * When this happens we need to emulate the rx vlan h/w acceleration
+			 * feature that is missing in the slave.
+			 */
+			if (!(skb->dev->features & NETIF_F_HW_VLAN_RX) &&
+			    (skb->dev->master->features & NETIF_F_HW_VLAN_RX)) {
+
+				struct bonding *bond = skb->dev->master->priv;
+				struct vlan_group *grp = bond->vlgrp;
+				struct ethhdr *hdr = eth_hdr(skb);
+
+				if (hdr->h_proto == htons(ETH_P_8021Q) && grp &&
+				    skb->len >= VLAN_ETH_HLEN) {
+					struct vlan_ethhdr *vhdr = vlan_eth_hdr(skb);
+					u16 vtag = ntohs(vhdr->h_vlan_TCI);
+
+					/* Reset skb->data to the start of the frame */
+					__skb_push(skb, skb->data - skb_mac_header(skb));
+
+					/* Ditch the 4 byte vlan shim */
+					memmove(skb_mac_header(skb) + VLAN_HLEN, skb_mac_header(skb), ETH_ALEN * 2);
+					__skb_pull(skb, VLAN_HLEN);
+
+					/* Update the skb details */
+					skb->protocol = eth_type_trans(skb, skb->dev);
+
+					/* Pass up the stack as if it came from bond0 */
+					vlan_hwaccel_rx(skb, grp, vtag);
+					return NET_RX_SUCCESS;
+				}
+			}
+		}
 	}
 
 	__get_cpu_var(netdev_rx_stat).total++;