Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

7 files changed, 1413 insertions, 0 deletions

diff --git a/kernel/net/ieee802154/6lowpan/6lowpan_i.h b/kernel/net/ieee802154/6lowpan/6lowpan_i.h
new file mode 100644
index 000000000..e50f69da7
--- /dev/null
+++ b/kernel/net/ieee802154/6lowpan/6lowpan_i.h
@@ -0,0 +1,72 @@
+#ifndef __IEEE802154_6LOWPAN_I_H__
+#define __IEEE802154_6LOWPAN_I_H__
+
+#include <linux/list.h>
+
+#include <net/ieee802154_netdev.h>
+#include <net/inet_frag.h>
+
+struct lowpan_create_arg {
+	u16 tag;
+	u16 d_size;
+	const struct ieee802154_addr *src;
+	const struct ieee802154_addr *dst;
+};
+
+/* Equivalent of ipv4 struct ip
+ */
+struct lowpan_frag_queue {
+	struct inet_frag_queue	q;
+
+	u16			tag;
+	u16			d_size;
+	struct ieee802154_addr	saddr;
+	struct ieee802154_addr	daddr;
+};
+
+static inline u32 ieee802154_addr_hash(const struct ieee802154_addr *a)
+{
+	switch (a->mode) {
+	case IEEE802154_ADDR_LONG:
+		return (((__force u64)a->extended_addr) >> 32) ^
+			(((__force u64)a->extended_addr) & 0xffffffff);
+	case IEEE802154_ADDR_SHORT:
+		return (__force u32)(a->short_addr);
+	default:
+		return 0;
+	}
+}
+
+struct lowpan_dev_record {
+	struct net_device *ldev;
+	struct list_head list;
+};
+
+/* private device info */
+struct lowpan_dev_info {
+	struct net_device	*real_dev; /* real WPAN device ptr */
+	struct mutex		dev_list_mtx; /* mutex for list ops */
+	u16			fragment_tag;
+};
+
+static inline struct
+lowpan_dev_info *lowpan_dev_info(const struct net_device *dev)
+{
+	return netdev_priv(dev);
+}
+
+extern struct list_head lowpan_devices;
+
+int lowpan_frag_rcv(struct sk_buff *skb, const u8 frag_type);
+void lowpan_net_frag_exit(void);
+int lowpan_net_frag_init(void);
+
+void lowpan_rx_init(void);
+void lowpan_rx_exit(void);
+
+int lowpan_header_create(struct sk_buff *skb, struct net_device *dev,
+			 unsigned short type, const void *_daddr,
+			 const void *_saddr, unsigned int len);
+netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *dev);
+
+#endif /* __IEEE802154_6LOWPAN_I_H__ */
diff --git a/kernel/net/ieee802154/6lowpan/Kconfig b/kernel/net/ieee802154/6lowpan/Kconfig
new file mode 100644
index 000000000..d24f985b0
--- /dev/null
+++ b/kernel/net/ieee802154/6lowpan/Kconfig
@@ -0,0 +1,5 @@
+config IEEE802154_6LOWPAN
+	tristate "6lowpan support over IEEE 802.15.4"
+	depends on 6LOWPAN
+	---help---
+	  IPv6 compression over IEEE 802.15.4.
diff --git a/kernel/net/ieee802154/6lowpan/Makefile b/kernel/net/ieee802154/6lowpan/Makefile
new file mode 100644
index 000000000..6bfb270a8
--- /dev/null
+++ b/kernel/net/ieee802154/6lowpan/Makefile
@@ -0,0 +1,3 @@
+obj-$(CONFIG_IEEE802154_6LOWPAN) += ieee802154_6lowpan.o
+
+ieee802154_6lowpan-y := core.o rx.o reassembly.o tx.o
diff --git a/kernel/net/ieee802154/6lowpan/core.c b/kernel/net/ieee802154/6lowpan/core.c
new file mode 100644
index 000000000..0ae5822ef
--- /dev/null
+++ b/kernel/net/ieee802154/6lowpan/core.c
@@ -0,0 +1,306 @@
+/* Copyright 2011, Siemens AG
+ * written by Alexander Smirnov <alex.bluesman.smirnov@gmail.com>
+ */
+
+/* Based on patches from Jon Smirl <jonsmirl@gmail.com>
+ * Copyright (c) 2011 Jon Smirl <jonsmirl@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+/* Jon's code is based on 6lowpan implementation for Contiki which is:
+ * Copyright (c) 2008, Swedish Institute of Computer Science.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/ieee802154.h>
+
+#include <net/ipv6.h>
+
+#include "6lowpan_i.h"
+
+LIST_HEAD(lowpan_devices);
+static int lowpan_open_count;
+
+static __le16 lowpan_get_pan_id(const struct net_device *dev)
+{
+	struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
+
+	return ieee802154_mlme_ops(real_dev)->get_pan_id(real_dev);
+}
+
+static __le16 lowpan_get_short_addr(const struct net_device *dev)
+{
+	struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
+
+	return ieee802154_mlme_ops(real_dev)->get_short_addr(real_dev);
+}
+
+static u8 lowpan_get_dsn(const struct net_device *dev)
+{
+	struct net_device *real_dev = lowpan_dev_info(dev)->real_dev;
+
+	return ieee802154_mlme_ops(real_dev)->get_dsn(real_dev);
+}
+
+static struct header_ops lowpan_header_ops = {
+	.create	= lowpan_header_create,
+};
+
+static struct lock_class_key lowpan_tx_busylock;
+static struct lock_class_key lowpan_netdev_xmit_lock_key;
+
+static void lowpan_set_lockdep_class_one(struct net_device *dev,
+					 struct netdev_queue *txq,
+					 void *_unused)
+{
+	lockdep_set_class(&txq->_xmit_lock,
+			  &lowpan_netdev_xmit_lock_key);
+}
+
+static int lowpan_dev_init(struct net_device *dev)
+{
+	netdev_for_each_tx_queue(dev, lowpan_set_lockdep_class_one, NULL);
+	dev->qdisc_tx_busylock = &lowpan_tx_busylock;
+	return 0;
+}
+
+static const struct net_device_ops lowpan_netdev_ops = {
+	.ndo_init		= lowpan_dev_init,
+	.ndo_start_xmit		= lowpan_xmit,
+};
+
+static struct ieee802154_mlme_ops lowpan_mlme = {
+	.get_pan_id = lowpan_get_pan_id,
+	.get_short_addr = lowpan_get_short_addr,
+	.get_dsn = lowpan_get_dsn,
+};
+
+static void lowpan_setup(struct net_device *dev)
+{
+	dev->addr_len		= IEEE802154_ADDR_LEN;
+	memset(dev->broadcast, 0xff, IEEE802154_ADDR_LEN);
+	dev->type		= ARPHRD_6LOWPAN;
+	/* Frame Control + Sequence Number + Address fields + Security Header */
+	dev->hard_header_len	= 2 + 1 + 20 + 14;
+	dev->needed_tailroom	= 2; /* FCS */
+	dev->mtu		= IPV6_MIN_MTU;
+	dev->tx_queue_len	= 0;
+	dev->flags		= IFF_BROADCAST | IFF_MULTICAST;
+	dev->watchdog_timeo	= 0;
+
+	dev->netdev_ops		= &lowpan_netdev_ops;
+	dev->header_ops		= &lowpan_header_ops;
+	dev->ml_priv		= &lowpan_mlme;
+	dev->destructor		= free_netdev;
+	dev->features		|= NETIF_F_NETNS_LOCAL;
+}
+
+static int lowpan_validate(struct nlattr *tb[], struct nlattr *data[])
+{
+	if (tb[IFLA_ADDRESS]) {
+		if (nla_len(tb[IFLA_ADDRESS]) != IEEE802154_ADDR_LEN)
+			return -EINVAL;
+	}
+	return 0;
+}
+
+static int lowpan_newlink(struct net *src_net, struct net_device *dev,
+			  struct nlattr *tb[], struct nlattr *data[])
+{
+	struct net_device *real_dev;
+	struct lowpan_dev_record *entry;
+	int ret;
+
+	ASSERT_RTNL();
+
+	pr_debug("adding new link\n");
+
+	if (!tb[IFLA_LINK] ||
+	    !net_eq(dev_net(dev), &init_net))
+		return -EINVAL;
+	/* find and hold real wpan device */
+	real_dev = dev_get_by_index(dev_net(dev), nla_get_u32(tb[IFLA_LINK]));
+	if (!real_dev)
+		return -ENODEV;
+	if (real_dev->type != ARPHRD_IEEE802154) {
+		dev_put(real_dev);
+		return -EINVAL;
+	}
+
+	lowpan_dev_info(dev)->real_dev = real_dev;
+	mutex_init(&lowpan_dev_info(dev)->dev_list_mtx);
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry) {
+		dev_put(real_dev);
+		lowpan_dev_info(dev)->real_dev = NULL;
+		return -ENOMEM;
+	}
+
+	entry->ldev = dev;
+
+	/* Set the lowpan hardware address to the wpan hardware address. */
+	memcpy(dev->dev_addr, real_dev->dev_addr, IEEE802154_ADDR_LEN);
+
+	mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
+	INIT_LIST_HEAD(&entry->list);
+	list_add_tail(&entry->list, &lowpan_devices);
+	mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
+
+	ret = register_netdevice(dev);
+	if (ret >= 0) {
+		if (!lowpan_open_count)
+			lowpan_rx_init();
+		lowpan_open_count++;
+	}
+
+	return ret;
+}
+
+static void lowpan_dellink(struct net_device *dev, struct list_head *head)
+{
+	struct lowpan_dev_info *lowpan_dev = lowpan_dev_info(dev);
+	struct net_device *real_dev = lowpan_dev->real_dev;
+	struct lowpan_dev_record *entry, *tmp;
+
+	ASSERT_RTNL();
+
+	lowpan_open_count--;
+	if (!lowpan_open_count)
+		lowpan_rx_exit();
+
+	mutex_lock(&lowpan_dev_info(dev)->dev_list_mtx);
+	list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
+		if (entry->ldev == dev) {
+			list_del(&entry->list);
+			kfree(entry);
+		}
+	}
+	mutex_unlock(&lowpan_dev_info(dev)->dev_list_mtx);
+
+	mutex_destroy(&lowpan_dev_info(dev)->dev_list_mtx);
+
+	unregister_netdevice_queue(dev, head);
+
+	dev_put(real_dev);
+}
+
+static struct rtnl_link_ops lowpan_link_ops __read_mostly = {
+	.kind		= "lowpan",
+	.priv_size	= sizeof(struct lowpan_dev_info),
+	.setup		= lowpan_setup,
+	.newlink	= lowpan_newlink,
+	.dellink	= lowpan_dellink,
+	.validate	= lowpan_validate,
+};
+
+static inline int __init lowpan_netlink_init(void)
+{
+	return rtnl_link_register(&lowpan_link_ops);
+}
+
+static inline void lowpan_netlink_fini(void)
+{
+	rtnl_link_unregister(&lowpan_link_ops);
+}
+
+static int lowpan_device_event(struct notifier_block *unused,
+			       unsigned long event, void *ptr)
+{
+	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
+	LIST_HEAD(del_list);
+	struct lowpan_dev_record *entry, *tmp;
+
+	if (dev->type != ARPHRD_IEEE802154)
+		goto out;
+
+	if (event == NETDEV_UNREGISTER) {
+		list_for_each_entry_safe(entry, tmp, &lowpan_devices, list) {
+			if (lowpan_dev_info(entry->ldev)->real_dev == dev)
+				lowpan_dellink(entry->ldev, &del_list);
+		}
+
+		unregister_netdevice_many(&del_list);
+	}
+
+out:
+	return NOTIFY_DONE;
+}
+
+static struct notifier_block lowpan_dev_notifier = {
+	.notifier_call = lowpan_device_event,
+};
+
+static int __init lowpan_init_module(void)
+{
+	int err = 0;
+
+	err = lowpan_net_frag_init();
+	if (err < 0)
+		goto out;
+
+	err = lowpan_netlink_init();
+	if (err < 0)
+		goto out_frag;
+
+	err = register_netdevice_notifier(&lowpan_dev_notifier);
+	if (err < 0)
+		goto out_pack;
+
+	return 0;
+
+out_pack:
+	lowpan_netlink_fini();
+out_frag:
+	lowpan_net_frag_exit();
+out:
+	return err;
+}
+
+static void __exit lowpan_cleanup_module(void)
+{
+	lowpan_netlink_fini();
+
+	lowpan_net_frag_exit();
+
+	unregister_netdevice_notifier(&lowpan_dev_notifier);
+}
+
+module_init(lowpan_init_module);
+module_exit(lowpan_cleanup_module);
+MODULE_LICENSE("GPL");
+MODULE_ALIAS_RTNL_LINK("lowpan");
diff --git a/kernel/net/ieee802154/6lowpan/reassembly.c b/kernel/net/ieee802154/6lowpan/reassembly.c
new file mode 100644
index 000000000..f46e4d130
--- /dev/null
+++ b/kernel/net/ieee802154/6lowpan/reassembly.c
@@ -0,0 +1,585 @@
+/*	6LoWPAN fragment reassembly
+ *
+ *
+ *	Authors:
+ *	Alexander Aring		<aar@pengutronix.de>
+ *
+ *	Based on: net/ipv6/reassembly.c
+ *
+ *	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.
+ */
+
+#define pr_fmt(fmt) "6LoWPAN: " fmt
+
+#include <linux/net.h>
+#include <linux/list.h>
+#include <linux/netdevice.h>
+#include <linux/random.h>
+#include <linux/jhash.h>
+#include <linux/skbuff.h>
+#include <linux/slab.h>
+#include <linux/export.h>
+
+#include <net/ieee802154_netdev.h>
+#include <net/6lowpan.h>
+#include <net/ipv6.h>
+#include <net/inet_frag.h>
+
+#include "6lowpan_i.h"
+
+static const char lowpan_frags_cache_name[] = "lowpan-frags";
+
+struct lowpan_frag_info {
+	u16 d_tag;
+	u16 d_size;
+	u8 d_offset;
+};
+
+static struct lowpan_frag_info *lowpan_cb(struct sk_buff *skb)
+{
+	return (struct lowpan_frag_info *)skb->cb;
+}
+
+static struct inet_frags lowpan_frags;
+
+static int lowpan_frag_reasm(struct lowpan_frag_queue *fq,
+			     struct sk_buff *prev, struct net_device *dev);
+
+static unsigned int lowpan_hash_frag(u16 tag, u16 d_size,
+				     const struct ieee802154_addr *saddr,
+				     const struct ieee802154_addr *daddr)
+{
+	net_get_random_once(&lowpan_frags.rnd, sizeof(lowpan_frags.rnd));
+	return jhash_3words(ieee802154_addr_hash(saddr),
+			    ieee802154_addr_hash(daddr),
+			    (__force u32)(tag + (d_size << 16)),
+			    lowpan_frags.rnd);
+}
+
+static unsigned int lowpan_hashfn(const struct inet_frag_queue *q)
+{
+	const struct lowpan_frag_queue *fq;
+
+	fq = container_of(q, struct lowpan_frag_queue, q);
+	return lowpan_hash_frag(fq->tag, fq->d_size, &fq->saddr, &fq->daddr);
+}
+
+static bool lowpan_frag_match(const struct inet_frag_queue *q, const void *a)
+{
+	const struct lowpan_frag_queue *fq;
+	const struct lowpan_create_arg *arg = a;
+
+	fq = container_of(q, struct lowpan_frag_queue, q);
+	return	fq->tag == arg->tag && fq->d_size == arg->d_size &&
+		ieee802154_addr_equal(&fq->saddr, arg->src) &&
+		ieee802154_addr_equal(&fq->daddr, arg->dst);
+}
+
+static void lowpan_frag_init(struct inet_frag_queue *q, const void *a)
+{
+	const struct lowpan_create_arg *arg = a;
+	struct lowpan_frag_queue *fq;
+
+	fq = container_of(q, struct lowpan_frag_queue, q);
+
+	fq->tag = arg->tag;
+	fq->d_size = arg->d_size;
+	fq->saddr = *arg->src;
+	fq->daddr = *arg->dst;
+}
+
+static void lowpan_frag_expire(unsigned long data)
+{
+	struct frag_queue *fq;
+	struct net *net;
+
+	fq = container_of((struct inet_frag_queue *)data, struct frag_queue, q);
+	net = container_of(fq->q.net, struct net, ieee802154_lowpan.frags);
+
+	spin_lock(&fq->q.lock);
+
+	if (fq->q.flags & INET_FRAG_COMPLETE)
+		goto out;
+
+	inet_frag_kill(&fq->q, &lowpan_frags);
+out:
+	spin_unlock(&fq->q.lock);
+	inet_frag_put(&fq->q, &lowpan_frags);
+}
+
+static inline struct lowpan_frag_queue *
+fq_find(struct net *net, const struct lowpan_frag_info *frag_info,
+	const struct ieee802154_addr *src,
+	const struct ieee802154_addr *dst)
+{
+	struct inet_frag_queue *q;
+	struct lowpan_create_arg arg;
+	unsigned int hash;
+	struct netns_ieee802154_lowpan *ieee802154_lowpan =
+		net_ieee802154_lowpan(net);
+
+	arg.tag = frag_info->d_tag;
+	arg.d_size = frag_info->d_size;
+	arg.src = src;
+	arg.dst = dst;
+
+	hash = lowpan_hash_frag(frag_info->d_tag, frag_info->d_size, src, dst);
+
+	q = inet_frag_find(&ieee802154_lowpan->frags,
+			   &lowpan_frags, &arg, hash);
+	if (IS_ERR_OR_NULL(q)) {
+		inet_frag_maybe_warn_overflow(q, pr_fmt());
+		return NULL;
+	}
+	return container_of(q, struct lowpan_frag_queue, q);
+}
+
+static int lowpan_frag_queue(struct lowpan_frag_queue *fq,
+			     struct sk_buff *skb, const u8 frag_type)
+{
+	struct sk_buff *prev, *next;
+	struct net_device *dev;
+	int end, offset;
+
+	if (fq->q.flags & INET_FRAG_COMPLETE)
+		goto err;
+
+	offset = lowpan_cb(skb)->d_offset << 3;
+	end = lowpan_cb(skb)->d_size;
+
+	/* Is this the final fragment? */
+	if (offset + skb->len == end) {
+		/* If we already have some bits beyond end
+		 * or have different end, the segment is corrupted.
+		 */
+		if (end < fq->q.len ||
+		    ((fq->q.flags & INET_FRAG_LAST_IN) && end != fq->q.len))
+			goto err;
+		fq->q.flags |= INET_FRAG_LAST_IN;
+		fq->q.len = end;
+	} else {
+		if (end > fq->q.len) {
+			/* Some bits beyond end -> corruption. */
+			if (fq->q.flags & INET_FRAG_LAST_IN)
+				goto err;
+			fq->q.len = end;
+		}
+	}
+
+	/* Find out which fragments are in front and at the back of us
+	 * in the chain of fragments so far.  We must know where to put
+	 * this fragment, right?
+	 */
+	prev = fq->q.fragments_tail;
+	if (!prev || lowpan_cb(prev)->d_offset < lowpan_cb(skb)->d_offset) {
+		next = NULL;
+		goto found;
+	}
+	prev = NULL;
+	for (next = fq->q.fragments; next != NULL; next = next->next) {
+		if (lowpan_cb(next)->d_offset >= lowpan_cb(skb)->d_offset)
+			break;	/* bingo! */
+		prev = next;
+	}
+
+found:
+	/* Insert this fragment in the chain of fragments. */
+	skb->next = next;
+	if (!next)
+		fq->q.fragments_tail = skb;
+	if (prev)
+		prev->next = skb;
+	else
+		fq->q.fragments = skb;
+
+	dev = skb->dev;
+	if (dev)
+		skb->dev = NULL;
+
+	fq->q.stamp = skb->tstamp;
+	if (frag_type == LOWPAN_DISPATCH_FRAG1) {
+		/* Calculate uncomp. 6lowpan header to estimate full size */
+		fq->q.meat += lowpan_uncompress_size(skb, NULL);
+		fq->q.flags |= INET_FRAG_FIRST_IN;
+	} else {
+		fq->q.meat += skb->len;
+	}
+	add_frag_mem_limit(&fq->q, skb->truesize);
+
+	if (fq->q.flags == (INET_FRAG_FIRST_IN | INET_FRAG_LAST_IN) &&
+	    fq->q.meat == fq->q.len) {
+		int res;
+		unsigned long orefdst = skb->_skb_refdst;
+
+		skb->_skb_refdst = 0UL;
+		res = lowpan_frag_reasm(fq, prev, dev);
+		skb->_skb_refdst = orefdst;
+		return res;
+	}
+
+	return -1;
+err:
+	kfree_skb(skb);
+	return -1;
+}
+
+/*	Check if this packet is complete.
+ *	Returns NULL on failure by any reason, and pointer
+ *	to current nexthdr field in reassembled frame.
+ *
+ *	It is called with locked fq, and caller must check that
+ *	queue is eligible for reassembly i.e. it is not COMPLETE,
+ *	the last and the first frames arrived and all the bits are here.
+ */
+static int lowpan_frag_reasm(struct lowpan_frag_queue *fq, struct sk_buff *prev,
+			     struct net_device *dev)
+{
+	struct sk_buff *fp, *head = fq->q.fragments;
+	int sum_truesize;
+
+	inet_frag_kill(&fq->q, &lowpan_frags);
+
+	/* Make the one we just received the head. */
+	if (prev) {
+		head = prev->next;
+		fp = skb_clone(head, GFP_ATOMIC);
+
+		if (!fp)
+			goto out_oom;
+
+		fp->next = head->next;
+		if (!fp->next)
+			fq->q.fragments_tail = fp;
+		prev->next = fp;
+
+		skb_morph(head, fq->q.fragments);
+		head->next = fq->q.fragments->next;
+
+		consume_skb(fq->q.fragments);
+		fq->q.fragments = head;
+	}
+
+	/* Head of list must not be cloned. */
+	if (skb_unclone(head, GFP_ATOMIC))
+		goto out_oom;
+
+	/* If the first fragment is fragmented itself, we split
+	 * it to two chunks: the first with data and paged part
+	 * and the second, holding only fragments.
+	 */
+	if (skb_has_frag_list(head)) {
+		struct sk_buff *clone;
+		int i, plen = 0;
+
+		clone = alloc_skb(0, GFP_ATOMIC);
+		if (!clone)
+			goto out_oom;
+		clone->next = head->next;
+		head->next = clone;
+		skb_shinfo(clone)->frag_list = skb_shinfo(head)->frag_list;
+		skb_frag_list_init(head);
+		for (i = 0; i < skb_shinfo(head)->nr_frags; i++)
+			plen += skb_frag_size(&skb_shinfo(head)->frags[i]);
+		clone->len = head->data_len - plen;
+		clone->data_len = clone->len;
+		head->data_len -= clone->len;
+		head->len -= clone->len;
+		add_frag_mem_limit(&fq->q, clone->truesize);
+	}
+
+	WARN_ON(head == NULL);
+
+	sum_truesize = head->truesize;
+	for (fp = head->next; fp;) {
+		bool headstolen;
+		int delta;
+		struct sk_buff *next = fp->next;
+
+		sum_truesize += fp->truesize;
+		if (skb_try_coalesce(head, fp, &headstolen, &delta)) {
+			kfree_skb_partial(fp, headstolen);
+		} else {
+			if (!skb_shinfo(head)->frag_list)
+				skb_shinfo(head)->frag_list = fp;
+			head->data_len += fp->len;
+			head->len += fp->len;
+			head->truesize += fp->truesize;
+		}
+		fp = next;
+	}
+	sub_frag_mem_limit(&fq->q, sum_truesize);
+
+	head->next = NULL;
+	head->dev = dev;
+	head->tstamp = fq->q.stamp;
+
+	fq->q.fragments = NULL;
+	fq->q.fragments_tail = NULL;
+
+	return 1;
+out_oom:
+	net_dbg_ratelimited("lowpan_frag_reasm: no memory for reassembly\n");
+	return -1;
+}
+
+static int lowpan_get_frag_info(struct sk_buff *skb, const u8 frag_type,
+				struct lowpan_frag_info *frag_info)
+{
+	bool fail;
+	u8 pattern = 0, low = 0;
+	__be16 d_tag = 0;
+
+	fail = lowpan_fetch_skb(skb, &pattern, 1);
+	fail |= lowpan_fetch_skb(skb, &low, 1);
+	frag_info->d_size = (pattern & 7) << 8 | low;
+	fail |= lowpan_fetch_skb(skb, &d_tag, 2);
+	frag_info->d_tag = ntohs(d_tag);
+
+	if (frag_type == LOWPAN_DISPATCH_FRAGN) {
+		fail |= lowpan_fetch_skb(skb, &frag_info->d_offset, 1);
+	} else {
+		skb_reset_network_header(skb);
+		frag_info->d_offset = 0;
+	}
+
+	if (unlikely(fail))
+		return -EIO;
+
+	return 0;
+}
+
+int lowpan_frag_rcv(struct sk_buff *skb, const u8 frag_type)
+{
+	struct lowpan_frag_queue *fq;
+	struct net *net = dev_net(skb->dev);
+	struct lowpan_frag_info *frag_info = lowpan_cb(skb);
+	struct ieee802154_addr source, dest;
+	int err;
+
+	source = mac_cb(skb)->source;
+	dest = mac_cb(skb)->dest;
+
+	err = lowpan_get_frag_info(skb, frag_type, frag_info);
+	if (err < 0)
+		goto err;
+
+	if (frag_info->d_size > IPV6_MIN_MTU) {
+		net_warn_ratelimited("lowpan_frag_rcv: datagram size exceeds MTU\n");
+		goto err;
+	}
+
+	fq = fq_find(net, frag_info, &source, &dest);
+	if (fq != NULL) {
+		int ret;
+
+		spin_lock(&fq->q.lock);
+		ret = lowpan_frag_queue(fq, skb, frag_type);
+		spin_unlock(&fq->q.lock);
+
+		inet_frag_put(&fq->q, &lowpan_frags);
+		return ret;
+	}
+
+err:
+	kfree_skb(skb);
+	return -1;
+}
+EXPORT_SYMBOL(lowpan_frag_rcv);
+
+#ifdef CONFIG_SYSCTL
+static int zero;
+
+static struct ctl_table lowpan_frags_ns_ctl_table[] = {
+	{
+		.procname	= "6lowpanfrag_high_thresh",
+		.data		= &init_net.ieee802154_lowpan.frags.high_thresh,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &init_net.ieee802154_lowpan.frags.low_thresh
+	},
+	{
+		.procname	= "6lowpanfrag_low_thresh",
+		.data		= &init_net.ieee802154_lowpan.frags.low_thresh,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_minmax,
+		.extra1		= &zero,
+		.extra2		= &init_net.ieee802154_lowpan.frags.high_thresh
+	},
+	{
+		.procname	= "6lowpanfrag_time",
+		.data		= &init_net.ieee802154_lowpan.frags.timeout,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
+	{ }
+};
+
+/* secret interval has been deprecated */
+static int lowpan_frags_secret_interval_unused;
+static struct ctl_table lowpan_frags_ctl_table[] = {
+	{
+		.procname	= "6lowpanfrag_secret_interval",
+		.data		= &lowpan_frags_secret_interval_unused,
+		.maxlen		= sizeof(int),
+		.mode		= 0644,
+		.proc_handler	= proc_dointvec_jiffies,
+	},
+	{ }
+};
+
+static int __net_init lowpan_frags_ns_sysctl_register(struct net *net)
+{
+	struct ctl_table *table;
+	struct ctl_table_header *hdr;
+	struct netns_ieee802154_lowpan *ieee802154_lowpan =
+		net_ieee802154_lowpan(net);
+
+	table = lowpan_frags_ns_ctl_table;
+	if (!net_eq(net, &init_net)) {
+		table = kmemdup(table, sizeof(lowpan_frags_ns_ctl_table),
+				GFP_KERNEL);
+		if (table == NULL)
+			goto err_alloc;
+
+		table[0].data = &ieee802154_lowpan->frags.high_thresh;
+		table[0].extra1 = &ieee802154_lowpan->frags.low_thresh;
+		table[0].extra2 = &init_net.ieee802154_lowpan.frags.high_thresh;
+		table[1].data = &ieee802154_lowpan->frags.low_thresh;
+		table[1].extra2 = &ieee802154_lowpan->frags.high_thresh;
+		table[2].data = &ieee802154_lowpan->frags.timeout;
+
+		/* Don't export sysctls to unprivileged users */
+		if (net->user_ns != &init_user_ns)
+			table[0].procname = NULL;
+	}
+
+	hdr = register_net_sysctl(net, "net/ieee802154/6lowpan", table);
+	if (hdr == NULL)
+		goto err_reg;
+
+	ieee802154_lowpan->sysctl.frags_hdr = hdr;
+	return 0;
+
+err_reg:
+	if (!net_eq(net, &init_net))
+		kfree(table);
+err_alloc:
+	return -ENOMEM;
+}
+
+static void __net_exit lowpan_frags_ns_sysctl_unregister(struct net *net)
+{
+	struct ctl_table *table;
+	struct netns_ieee802154_lowpan *ieee802154_lowpan =
+		net_ieee802154_lowpan(net);
+
+	table = ieee802154_lowpan->sysctl.frags_hdr->ctl_table_arg;
+	unregister_net_sysctl_table(ieee802154_lowpan->sysctl.frags_hdr);
+	if (!net_eq(net, &init_net))
+		kfree(table);
+}
+
+static struct ctl_table_header *lowpan_ctl_header;
+
+static int __init lowpan_frags_sysctl_register(void)
+{
+	lowpan_ctl_header = register_net_sysctl(&init_net,
+						"net/ieee802154/6lowpan",
+						lowpan_frags_ctl_table);
+	return lowpan_ctl_header == NULL ? -ENOMEM : 0;
+}
+
+static void lowpan_frags_sysctl_unregister(void)
+{
+	unregister_net_sysctl_table(lowpan_ctl_header);
+}
+#else
+static inline int lowpan_frags_ns_sysctl_register(struct net *net)
+{
+	return 0;
+}
+
+static inline void lowpan_frags_ns_sysctl_unregister(struct net *net)
+{
+}
+
+static inline int __init lowpan_frags_sysctl_register(void)
+{
+	return 0;
+}
+
+static inline void lowpan_frags_sysctl_unregister(void)
+{
+}
+#endif
+
+static int __net_init lowpan_frags_init_net(struct net *net)
+{
+	struct netns_ieee802154_lowpan *ieee802154_lowpan =
+		net_ieee802154_lowpan(net);
+
+	ieee802154_lowpan->frags.high_thresh = IPV6_FRAG_HIGH_THRESH;
+	ieee802154_lowpan->frags.low_thresh = IPV6_FRAG_LOW_THRESH;
+	ieee802154_lowpan->frags.timeout = IPV6_FRAG_TIMEOUT;
+
+	inet_frags_init_net(&ieee802154_lowpan->frags);
+
+	return lowpan_frags_ns_sysctl_register(net);
+}
+
+static void __net_exit lowpan_frags_exit_net(struct net *net)
+{
+	struct netns_ieee802154_lowpan *ieee802154_lowpan =
+		net_ieee802154_lowpan(net);
+
+	lowpan_frags_ns_sysctl_unregister(net);
+	inet_frags_exit_net(&ieee802154_lowpan->frags, &lowpan_frags);
+}
+
+static struct pernet_operations lowpan_frags_ops = {
+	.init = lowpan_frags_init_net,
+	.exit = lowpan_frags_exit_net,
+};
+
+int __init lowpan_net_frag_init(void)
+{
+	int ret;
+
+	ret = lowpan_frags_sysctl_register();
+	if (ret)
+		return ret;
+
+	ret = register_pernet_subsys(&lowpan_frags_ops);
+	if (ret)
+		goto err_pernet;
+
+	lowpan_frags.hashfn = lowpan_hashfn;
+	lowpan_frags.constructor = lowpan_frag_init;
+	lowpan_frags.destructor = NULL;
+	lowpan_frags.skb_free = NULL;
+	lowpan_frags.qsize = sizeof(struct frag_queue);
+	lowpan_frags.match = lowpan_frag_match;
+	lowpan_frags.frag_expire = lowpan_frag_expire;
+	lowpan_frags.frags_cache_name = lowpan_frags_cache_name;
+	ret = inet_frags_init(&lowpan_frags);
+	if (ret)
+		goto err_pernet;
+
+	return ret;
+err_pernet:
+	lowpan_frags_sysctl_unregister();
+	return ret;
+}
+
+void lowpan_net_frag_exit(void)
+{
+	inet_frags_fini(&lowpan_frags);
+	lowpan_frags_sysctl_unregister();
+	unregister_pernet_subsys(&lowpan_frags_ops);
+}
diff --git a/kernel/net/ieee802154/6lowpan/rx.c b/kernel/net/ieee802154/6lowpan/rx.c
new file mode 100644
index 000000000..4be1d289a
--- /dev/null
+++ b/kernel/net/ieee802154/6lowpan/rx.c
@@ -0,0 +1,171 @@
+/* This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/if_arp.h>
+
+#include <net/6lowpan.h>
+#include <net/ieee802154_netdev.h>
+
+#include "6lowpan_i.h"
+
+static int lowpan_give_skb_to_devices(struct sk_buff *skb,
+				      struct net_device *dev)
+{
+	struct lowpan_dev_record *entry;
+	struct sk_buff *skb_cp;
+	int stat = NET_RX_SUCCESS;
+
+	skb->protocol = htons(ETH_P_IPV6);
+	skb->pkt_type = PACKET_HOST;
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(entry, &lowpan_devices, list)
+		if (lowpan_dev_info(entry->ldev)->real_dev == skb->dev) {
+			skb_cp = skb_copy(skb, GFP_ATOMIC);
+			if (!skb_cp) {
+				kfree_skb(skb);
+				rcu_read_unlock();
+				return NET_RX_DROP;
+			}
+
+			skb_cp->dev = entry->ldev;
+			stat = netif_rx(skb_cp);
+			if (stat == NET_RX_DROP)
+				break;
+		}
+	rcu_read_unlock();
+
+	consume_skb(skb);
+
+	return stat;
+}
+
+static int
+iphc_decompress(struct sk_buff *skb, const struct ieee802154_hdr *hdr)
+{
+	u8 iphc0, iphc1;
+	struct ieee802154_addr_sa sa, da;
+	void *sap, *dap;
+
+	raw_dump_table(__func__, "raw skb data dump", skb->data, skb->len);
+	/* at least two bytes will be used for the encoding */
+	if (skb->len < 2)
+		return -EINVAL;
+
+	if (lowpan_fetch_skb_u8(skb, &iphc0))
+		return -EINVAL;
+
+	if (lowpan_fetch_skb_u8(skb, &iphc1))
+		return -EINVAL;
+
+	ieee802154_addr_to_sa(&sa, &hdr->source);
+	ieee802154_addr_to_sa(&da, &hdr->dest);
+
+	if (sa.addr_type == IEEE802154_ADDR_SHORT)
+		sap = &sa.short_addr;
+	else
+		sap = &sa.hwaddr;
+
+	if (da.addr_type == IEEE802154_ADDR_SHORT)
+		dap = &da.short_addr;
+	else
+		dap = &da.hwaddr;
+
+	return lowpan_header_decompress(skb, skb->dev, sap, sa.addr_type,
+					IEEE802154_ADDR_LEN, dap, da.addr_type,
+					IEEE802154_ADDR_LEN, iphc0, iphc1);
+}
+
+static int lowpan_rcv(struct sk_buff *skb, struct net_device *dev,
+		      struct packet_type *pt, struct net_device *orig_dev)
+{
+	struct ieee802154_hdr hdr;
+	int ret;
+
+	skb = skb_share_check(skb, GFP_ATOMIC);
+	if (!skb)
+		goto drop;
+
+	if (!netif_running(dev))
+		goto drop_skb;
+
+	if (skb->pkt_type == PACKET_OTHERHOST)
+		goto drop_skb;
+
+	if (dev->type != ARPHRD_IEEE802154)
+		goto drop_skb;
+
+	if (ieee802154_hdr_peek_addrs(skb, &hdr) < 0)
+		goto drop_skb;
+
+	/* check that it's our buffer */
+	if (skb->data[0] == LOWPAN_DISPATCH_IPV6) {
+		/* Pull off the 1-byte of 6lowpan header. */
+		skb_pull(skb, 1);
+		return lowpan_give_skb_to_devices(skb, NULL);
+	} else {
+		switch (skb->data[0] & 0xe0) {
+		case LOWPAN_DISPATCH_IPHC:	/* ipv6 datagram */
+			ret = iphc_decompress(skb, &hdr);
+			if (ret < 0)
+				goto drop_skb;
+
+			return lowpan_give_skb_to_devices(skb, NULL);
+		case LOWPAN_DISPATCH_FRAG1:	/* first fragment header */
+			ret = lowpan_frag_rcv(skb, LOWPAN_DISPATCH_FRAG1);
+			if (ret == 1) {
+				ret = iphc_decompress(skb, &hdr);
+				if (ret < 0)
+					goto drop_skb;
+
+				return lowpan_give_skb_to_devices(skb, NULL);
+			} else if (ret == -1) {
+				return NET_RX_DROP;
+			} else {
+				return NET_RX_SUCCESS;
+			}
+		case LOWPAN_DISPATCH_FRAGN:	/* next fragments headers */
+			ret = lowpan_frag_rcv(skb, LOWPAN_DISPATCH_FRAGN);
+			if (ret == 1) {
+				ret = iphc_decompress(skb, &hdr);
+				if (ret < 0)
+					goto drop_skb;
+
+				return lowpan_give_skb_to_devices(skb, NULL);
+			} else if (ret == -1) {
+				return NET_RX_DROP;
+			} else {
+				return NET_RX_SUCCESS;
+			}
+		default:
+			break;
+		}
+	}
+
+drop_skb:
+	kfree_skb(skb);
+drop:
+	return NET_RX_DROP;
+}
+
+static struct packet_type lowpan_packet_type = {
+	.type = htons(ETH_P_IEEE802154),
+	.func = lowpan_rcv,
+};
+
+void lowpan_rx_init(void)
+{
+	dev_add_pack(&lowpan_packet_type);
+}
+
+void lowpan_rx_exit(void)
+{
+	dev_remove_pack(&lowpan_packet_type);
+}
diff --git a/kernel/net/ieee802154/6lowpan/tx.c b/kernel/net/ieee802154/6lowpan/tx.c
new file mode 100644
index 000000000..2349070bd
--- /dev/null
+++ b/kernel/net/ieee802154/6lowpan/tx.c
@@ -0,0 +1,271 @@
+/* This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <net/6lowpan.h>
+#include <net/ieee802154_netdev.h>
+
+#include "6lowpan_i.h"
+
+/* don't save pan id, it's intra pan */
+struct lowpan_addr {
+	u8 mode;
+	union {
+		/* IPv6 needs big endian here */
+		__be64 extended_addr;
+		__be16 short_addr;
+	} u;
+};
+
+struct lowpan_addr_info {
+	struct lowpan_addr daddr;
+	struct lowpan_addr saddr;
+};
+
+static inline struct
+lowpan_addr_info *lowpan_skb_priv(const struct sk_buff *skb)
+{
+	WARN_ON_ONCE(skb_headroom(skb) < sizeof(struct lowpan_addr_info));
+	return (struct lowpan_addr_info *)(skb->data -
+			sizeof(struct lowpan_addr_info));
+}
+
+int lowpan_header_create(struct sk_buff *skb, struct net_device *dev,
+			 unsigned short type, const void *_daddr,
+			 const void *_saddr, unsigned int len)
+{
+	const u8 *saddr = _saddr;
+	const u8 *daddr = _daddr;
+	struct lowpan_addr_info *info;
+
+	/* TODO:
+	 * if this package isn't ipv6 one, where should it be routed?
+	 */
+	if (type != ETH_P_IPV6)
+		return 0;
+
+	if (!saddr)
+		saddr = dev->dev_addr;
+
+	raw_dump_inline(__func__, "saddr", (unsigned char *)saddr, 8);
+	raw_dump_inline(__func__, "daddr", (unsigned char *)daddr, 8);
+
+	info = lowpan_skb_priv(skb);
+
+	/* TODO: Currently we only support extended_addr */
+	info->daddr.mode = IEEE802154_ADDR_LONG;
+	memcpy(&info->daddr.u.extended_addr, daddr,
+	       sizeof(info->daddr.u.extended_addr));
+	info->saddr.mode = IEEE802154_ADDR_LONG;
+	memcpy(&info->saddr.u.extended_addr, saddr,
+	       sizeof(info->daddr.u.extended_addr));
+
+	return 0;
+}
+
+static struct sk_buff*
+lowpan_alloc_frag(struct sk_buff *skb, int size,
+		  const struct ieee802154_hdr *master_hdr)
+{
+	struct net_device *real_dev = lowpan_dev_info(skb->dev)->real_dev;
+	struct sk_buff *frag;
+	int rc;
+
+	frag = alloc_skb(real_dev->hard_header_len +
+			 real_dev->needed_tailroom + size,
+			 GFP_ATOMIC);
+
+	if (likely(frag)) {
+		frag->dev = real_dev;
+		frag->priority = skb->priority;
+		skb_reserve(frag, real_dev->hard_header_len);
+		skb_reset_network_header(frag);
+		*mac_cb(frag) = *mac_cb(skb);
+
+		rc = dev_hard_header(frag, real_dev, 0, &master_hdr->dest,
+				     &master_hdr->source, size);
+		if (rc < 0) {
+			kfree_skb(frag);
+			return ERR_PTR(rc);
+		}
+	} else {
+		frag = ERR_PTR(-ENOMEM);
+	}
+
+	return frag;
+}
+
+static int
+lowpan_xmit_fragment(struct sk_buff *skb, const struct ieee802154_hdr *wpan_hdr,
+		     u8 *frag_hdr, int frag_hdrlen,
+		     int offset, int len)
+{
+	struct sk_buff *frag;
+
+	raw_dump_inline(__func__, " fragment header", frag_hdr, frag_hdrlen);
+
+	frag = lowpan_alloc_frag(skb, frag_hdrlen + len, wpan_hdr);
+	if (IS_ERR(frag))
+		return -PTR_ERR(frag);
+
+	memcpy(skb_put(frag, frag_hdrlen), frag_hdr, frag_hdrlen);
+	memcpy(skb_put(frag, len), skb_network_header(skb) + offset, len);
+
+	raw_dump_table(__func__, " fragment dump", frag->data, frag->len);
+
+	return dev_queue_xmit(frag);
+}
+
+static int
+lowpan_xmit_fragmented(struct sk_buff *skb, struct net_device *dev,
+		       const struct ieee802154_hdr *wpan_hdr)
+{
+	u16 dgram_size, dgram_offset;
+	__be16 frag_tag;
+	u8 frag_hdr[5];
+	int frag_cap, frag_len, payload_cap, rc;
+	int skb_unprocessed, skb_offset;
+
+	dgram_size = lowpan_uncompress_size(skb, &dgram_offset) -
+		     skb->mac_len;
+	frag_tag = htons(lowpan_dev_info(dev)->fragment_tag);
+	lowpan_dev_info(dev)->fragment_tag++;
+
+	frag_hdr[0] = LOWPAN_DISPATCH_FRAG1 | ((dgram_size >> 8) & 0x07);
+	frag_hdr[1] = dgram_size & 0xff;
+	memcpy(frag_hdr + 2, &frag_tag, sizeof(frag_tag));
+
+	payload_cap = ieee802154_max_payload(wpan_hdr);
+
+	frag_len = round_down(payload_cap - LOWPAN_FRAG1_HEAD_SIZE -
+			      skb_network_header_len(skb), 8);
+
+	skb_offset = skb_network_header_len(skb);
+	skb_unprocessed = skb->len - skb->mac_len - skb_offset;
+
+	rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
+				  LOWPAN_FRAG1_HEAD_SIZE, 0,
+				  frag_len + skb_network_header_len(skb));
+	if (rc) {
+		pr_debug("%s unable to send FRAG1 packet (tag: %d)",
+			 __func__, ntohs(frag_tag));
+		goto err;
+	}
+
+	frag_hdr[0] &= ~LOWPAN_DISPATCH_FRAG1;
+	frag_hdr[0] |= LOWPAN_DISPATCH_FRAGN;
+	frag_cap = round_down(payload_cap - LOWPAN_FRAGN_HEAD_SIZE, 8);
+
+	do {
+		dgram_offset += frag_len;
+		skb_offset += frag_len;
+		skb_unprocessed -= frag_len;
+		frag_len = min(frag_cap, skb_unprocessed);
+
+		frag_hdr[4] = dgram_offset >> 3;
+
+		rc = lowpan_xmit_fragment(skb, wpan_hdr, frag_hdr,
+					  LOWPAN_FRAGN_HEAD_SIZE, skb_offset,
+					  frag_len);
+		if (rc) {
+			pr_debug("%s unable to send a FRAGN packet. (tag: %d, offset: %d)\n",
+				 __func__, ntohs(frag_tag), skb_offset);
+			goto err;
+		}
+	} while (skb_unprocessed > frag_cap);
+
+	consume_skb(skb);
+	return NET_XMIT_SUCCESS;
+
+err:
+	kfree_skb(skb);
+	return rc;
+}
+
+static int lowpan_header(struct sk_buff *skb, struct net_device *dev)
+{
+	struct ieee802154_addr sa, da;
+	struct ieee802154_mac_cb *cb = mac_cb_init(skb);
+	struct lowpan_addr_info info;
+	void *daddr, *saddr;
+
+	memcpy(&info, lowpan_skb_priv(skb), sizeof(info));
+
+	/* TODO: Currently we only support extended_addr */
+	daddr = &info.daddr.u.extended_addr;
+	saddr = &info.saddr.u.extended_addr;
+
+	lowpan_header_compress(skb, dev, ETH_P_IPV6, daddr, saddr, skb->len);
+
+	cb->type = IEEE802154_FC_TYPE_DATA;
+
+	/* prepare wpan address data */
+	sa.mode = IEEE802154_ADDR_LONG;
+	sa.pan_id = ieee802154_mlme_ops(dev)->get_pan_id(dev);
+	sa.extended_addr = ieee802154_devaddr_from_raw(saddr);
+
+	/* intra-PAN communications */
+	da.pan_id = sa.pan_id;
+
+	/* if the destination address is the broadcast address, use the
+	 * corresponding short address
+	 */
+	if (lowpan_is_addr_broadcast((const u8 *)daddr)) {
+		da.mode = IEEE802154_ADDR_SHORT;
+		da.short_addr = cpu_to_le16(IEEE802154_ADDR_BROADCAST);
+		cb->ackreq = false;
+	} else {
+		da.mode = IEEE802154_ADDR_LONG;
+		da.extended_addr = ieee802154_devaddr_from_raw(daddr);
+		cb->ackreq = true;
+	}
+
+	return dev_hard_header(skb, lowpan_dev_info(dev)->real_dev,
+			ETH_P_IPV6, (void *)&da, (void *)&sa, 0);
+}
+
+netdev_tx_t lowpan_xmit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct ieee802154_hdr wpan_hdr;
+	int max_single, ret;
+
+	pr_debug("package xmit\n");
+
+	/* We must take a copy of the skb before we modify/replace the ipv6
+	 * header as the header could be used elsewhere
+	 */
+	skb = skb_unshare(skb, GFP_ATOMIC);
+	if (!skb)
+		return NET_XMIT_DROP;
+
+	ret = lowpan_header(skb, dev);
+	if (ret < 0) {
+		kfree_skb(skb);
+		return NET_XMIT_DROP;
+	}
+
+	if (ieee802154_hdr_peek(skb, &wpan_hdr) < 0) {
+		kfree_skb(skb);
+		return NET_XMIT_DROP;
+	}
+
+	max_single = ieee802154_max_payload(&wpan_hdr);
+
+	if (skb_tail_pointer(skb) - skb_network_header(skb) <= max_single) {
+		skb->dev = lowpan_dev_info(dev)->real_dev;
+		return dev_queue_xmit(skb);
+	} else {
+		netdev_tx_t rc;
+
+		pr_debug("frame is too big, fragmentation is needed\n");
+		rc = lowpan_xmit_fragmented(skb, dev, &wpan_hdr);
+
+		return rc < 0 ? NET_XMIT_DROP : rc;
+	}
+}