--- /dev/null
+/*
+ * net/dsa/tag_qinq.c - QinQ tag format handling
+ * Copyright (c) 2010 Gabor Juhos <juhosg@openwrt.org>
+ *
+ * This file was based on:
+ * net/dsa/tag_edsa.c - Ethertype DSA tagging
+ * Copyright (c) 2008-2009 Marvell Semiconductor
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/etherdevice.h>
+#include <linux/list.h>
+#include <linux/netdevice.h>
+#include <linux/if_vlan.h>
+
+#include "dsa_priv.h"
+
+netdev_tx_t qinq_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+ struct dsa_slave_priv *p = netdev_priv(dev);
+ struct vlan_ethhdr *veth;
+ unsigned int len;
+ int ret;
+
+ if (skb_cow_head(skb, VLAN_HLEN) < 0)
+ goto out_free_skb;
+
+ veth = (struct vlan_ethhdr *)skb_push(skb, VLAN_HLEN);
+
+ /* Move the mac addresses to the beginning of the new header. */
+ memmove(skb->data, skb->data + VLAN_HLEN, 2 * VLAN_ETH_ALEN);
+ skb->mac_header -= VLAN_HLEN;
+
+ /* setup VLAN header fields */
+ veth->h_vlan_proto = htons(ETH_P_QINQ);
+ veth->h_vlan_TCI = htons(p->port);
+
+ len = skb->len;
+ skb->protocol = htons(ETH_P_QINQ);
+ skb->dev = p->parent->dst->master_netdev;
+
+ ret = dev_queue_xmit(skb);
+ if (unlikely(ret != NET_XMIT_SUCCESS))
+ goto out_dropped;
+
+ dev->stats.tx_packets++;
+ dev->stats.tx_bytes += len;
+
+ return NETDEV_TX_OK;
+
+ out_free_skb:
+ kfree_skb(skb);
+ out_dropped:
+ dev->stats.tx_dropped++;
+ return NETDEV_TX_OK;
+}
+
+static int qinq_rcv(struct sk_buff *skb, struct net_device *dev,
+ struct packet_type *pt, struct net_device *orig_dev)
+{
+ struct dsa_switch_tree *dst;
+ struct dsa_switch *ds;
+ struct vlan_hdr *vhdr;
+ int source_port;
+
+ dst = dev->dsa_ptr;
+ if (unlikely(dst == NULL))
+ goto out_drop;
+ ds = dst->ds[0];
+
+ skb = skb_unshare(skb, GFP_ATOMIC);
+ if (skb == NULL)
+ goto out;
+
+ if (unlikely(!pskb_may_pull(skb, VLAN_HLEN)))
+ goto out_drop;
+
+ vhdr = (struct vlan_hdr *)skb->data;
+ source_port = ntohs(vhdr->h_vlan_TCI) & VLAN_VID_MASK;
+ if (source_port >= DSA_MAX_PORTS || ds->ports[source_port] == NULL)
+ goto out_drop;
+
+ /* Remove the outermost VLAN tag and update checksum. */
+ skb_pull_rcsum(skb, VLAN_HLEN);
+ memmove(skb->data - ETH_HLEN,
+ skb->data - ETH_HLEN - VLAN_HLEN,
+ 2 * ETH_ALEN);
+
+ skb->dev = ds->ports[source_port];
+ skb_push(skb, ETH_HLEN);
+ skb->pkt_type = PACKET_HOST;
+ skb->protocol = eth_type_trans(skb, skb->dev);
+
+ skb->dev->stats.rx_packets++;
+ skb->dev->stats.rx_bytes += skb->len;
+
+ netif_receive_skb(skb);
+
+ return 0;
+
+ out_drop:
+ kfree_skb(skb);
+ out:
+ return 0;
+}
+
+static struct packet_type qinq_packet_type __read_mostly = {
+ .type = cpu_to_be16(ETH_P_QINQ),
+ .func = qinq_rcv,
+};
+
+static int __init qinq_init_module(void)
+{
+ dev_add_pack(&qinq_packet_type);
+ return 0;
+}
+module_init(qinq_init_module);
+
+static void __exit qinq_cleanup_module(void)
+{
+ dev_remove_pack(&qinq_packet_type);
+}
+module_exit(qinq_cleanup_module);
--- /dev/null
+--- a/include/linux/if_ether.h
++++ b/include/linux/if_ether.h
+@@ -81,6 +81,7 @@
+ #define ETH_P_1588 0x88F7 /* IEEE 1588 Timesync */
+ #define ETH_P_FCOE 0x8906 /* Fibre Channel over Ethernet */
+ #define ETH_P_FIP 0x8914 /* FCoE Initialization Protocol */
++#define ETH_P_QINQ 0x9100 /* QinQ VLAN Stacking Protocol */
+ #define ETH_P_EDSA 0xDADA /* Ethertype DSA [ NOT AN OFFICIALLY REGISTERED ID ] */
+
+ /*
+--- a/net/dsa/dsa_priv.h
++++ b/net/dsa/dsa_priv.h
+@@ -174,6 +174,9 @@ netdev_tx_t dsa_xmit(struct sk_buff *skb
+ /* tag_edsa.c */
+ netdev_tx_t edsa_xmit(struct sk_buff *skb, struct net_device *dev);
+
++/* tag_qinq.c */
++netdev_tx_t qinq_xmit(struct sk_buff *skb, struct net_device *dev);
++
+ /* tag_trailer.c */
+ netdev_tx_t trailer_xmit(struct sk_buff *skb, struct net_device *dev);
+
+--- a/net/dsa/Kconfig
++++ b/net/dsa/Kconfig
+@@ -23,6 +23,10 @@ config NET_DSA_TAG_TRAILER
+ bool
+ default n
+
++config NET_DSA_TAG_QINQ
++ bool
++ default y
++
+
+ # switch drivers
+ config NET_DSA_MV88E6XXX
+--- a/net/dsa/Makefile
++++ b/net/dsa/Makefile
+@@ -1,6 +1,7 @@
+ # tagging formats
+ obj-$(CONFIG_NET_DSA_TAG_DSA) += tag_dsa.o
+ obj-$(CONFIG_NET_DSA_TAG_EDSA) += tag_edsa.o
++obj-$(CONFIG_NET_DSA_TAG_QINQ) += tag_qinq.o
+ obj-$(CONFIG_NET_DSA_TAG_TRAILER) += tag_trailer.o
+
+ # switch drivers
+--- a/net/dsa/slave.c
++++ b/net/dsa/slave.c
+@@ -321,6 +321,19 @@ static const struct net_device_ops edsa_
+ .ndo_do_ioctl = dsa_slave_ioctl,
+ };
+ #endif
++#ifdef CONFIG_NET_DSA_TAG_QINQ
++static const struct net_device_ops qinq_netdev_ops = {
++ .ndo_init = dsa_slave_init,
++ .ndo_open = dsa_slave_open,
++ .ndo_stop = dsa_slave_close,
++ .ndo_start_xmit = qinq_xmit,
++ .ndo_change_rx_flags = dsa_slave_change_rx_flags,
++ .ndo_set_rx_mode = dsa_slave_set_rx_mode,
++ .ndo_set_multicast_list = dsa_slave_set_rx_mode,
++ .ndo_set_mac_address = dsa_slave_set_mac_address,
++ .ndo_do_ioctl = dsa_slave_ioctl,
++};
++#endif
+ #ifdef CONFIG_NET_DSA_TAG_TRAILER
+ static const struct net_device_ops trailer_netdev_ops = {
+ .ndo_init = dsa_slave_init,
+@@ -366,6 +379,11 @@ dsa_slave_create(struct dsa_switch *ds,
+ slave_dev->netdev_ops = &edsa_netdev_ops;
+ break;
+ #endif
++#ifdef CONFIG_NET_DSA_TAG_QINQ
++ case htons(ETH_P_QINQ):
++ slave_dev->netdev_ops = &qinq_netdev_ops;
++ break;
++#endif
+ #ifdef CONFIG_NET_DSA_TAG_TRAILER
+ case htons(ETH_P_TRAILER):
+ slave_dev->netdev_ops = &trailer_netdev_ops;