Initial import

1 files changed, 7523 insertions, 0 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
new file mode 100644
index 000000000..aa82f9ab6
--- /dev/null
+++ b/net/core/dev.c
@@ -0,0 +1,7523 @@
+/*
+ * 	NET3	Protocol independent device support routines.
+ *
+ *		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.
+ *
+ *	Derived from the non IP parts of dev.c 1.0.19
+ * 		Authors:	Ross Biro
+ *				Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ *				Mark Evans, <evansmp@uhura.aston.ac.uk>
+ *
+ *	Additional Authors:
+ *		Florian la Roche <rzsfl@rz.uni-sb.de>
+ *		Alan Cox <gw4pts@gw4pts.ampr.org>
+ *		David Hinds <dahinds@users.sourceforge.net>
+ *		Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
+ *		Adam Sulmicki <adam@cfar.umd.edu>
+ *              Pekka Riikonen <priikone@poesidon.pspt.fi>
+ *
+ *	Changes:
+ *              D.J. Barrow     :       Fixed bug where dev->refcnt gets set
+ *              			to 2 if register_netdev gets called
+ *              			before net_dev_init & also removed a
+ *              			few lines of code in the process.
+ *		Alan Cox	:	device private ioctl copies fields back.
+ *		Alan Cox	:	Transmit queue code does relevant
+ *					stunts to keep the queue safe.
+ *		Alan Cox	:	Fixed double lock.
+ *		Alan Cox	:	Fixed promisc NULL pointer trap
+ *		????????	:	Support the full private ioctl range
+ *		Alan Cox	:	Moved ioctl permission check into
+ *					drivers
+ *		Tim Kordas	:	SIOCADDMULTI/SIOCDELMULTI
+ *		Alan Cox	:	100 backlog just doesn't cut it when
+ *					you start doing multicast video 8)
+ *		Alan Cox	:	Rewrote net_bh and list manager.
+ *		Alan Cox	: 	Fix ETH_P_ALL echoback lengths.
+ *		Alan Cox	:	Took out transmit every packet pass
+ *					Saved a few bytes in the ioctl handler
+ *		Alan Cox	:	Network driver sets packet type before
+ *					calling netif_rx. Saves a function
+ *					call a packet.
+ *		Alan Cox	:	Hashed net_bh()
+ *		Richard Kooijman:	Timestamp fixes.
+ *		Alan Cox	:	Wrong field in SIOCGIFDSTADDR
+ *		Alan Cox	:	Device lock protection.
+ *		Alan Cox	: 	Fixed nasty side effect of device close
+ *					changes.
+ *		Rudi Cilibrasi	:	Pass the right thing to
+ *					set_mac_address()
+ *		Dave Miller	:	32bit quantity for the device lock to
+ *					make it work out on a Sparc.
+ *		Bjorn Ekwall	:	Added KERNELD hack.
+ *		Alan Cox	:	Cleaned up the backlog initialise.
+ *		Craig Metz	:	SIOCGIFCONF fix if space for under
+ *					1 device.
+ *	    Thomas Bogendoerfer :	Return ENODEV for dev_open, if there
+ *					is no device open function.
+ *		Andi Kleen	:	Fix error reporting for SIOCGIFCONF
+ *	    Michael Chastain	:	Fix signed/unsigned for SIOCGIFCONF
+ *		Cyrus Durgin	:	Cleaned for KMOD
+ *		Adam Sulmicki   :	Bug Fix : Network Device Unload
+ *					A network device unload needs to purge
+ *					the backlog queue.
+ *	Paul Rusty Russell	:	SIOCSIFNAME
+ *              Pekka Riikonen  :	Netdev boot-time settings code
+ *              Andrew Morton   :       Make unregister_netdevice wait
+ *              			indefinitely on dev->refcnt
+ * 		J Hadi Salim	:	- Backlog queue sampling
+ *				        - netif_rx() feedback
+ */
+
+#include <asm/uaccess.h>
+#include <linux/bitops.h>
+#include <linux/capability.h>
+#include <linux/cpu.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/hash.h>
+#include <linux/slab.h>
+#include <linux/sched.h>
+#include <linux/mutex.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/sockios.h>
+#include <linux/errno.h>
+#include <linux/interrupt.h>
+#include <linux/if_ether.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/notifier.h>
+#include <linux/skbuff.h>
+#include <net/net_namespace.h>
+#include <net/sock.h>
+#include <linux/rtnetlink.h>
+#include <linux/stat.h>
+#include <net/dst.h>
+#include <net/pkt_sched.h>
+#include <net/checksum.h>
+#include <net/xfrm.h>
+#include <linux/highmem.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/netpoll.h>
+#include <linux/rcupdate.h>
+#include <linux/delay.h>
+#include <net/iw_handler.h>
+#include <asm/current.h>
+#include <linux/audit.h>
+#include <linux/dmaengine.h>
+#include <linux/err.h>
+#include <linux/ctype.h>
+#include <linux/if_arp.h>
+#include <linux/if_vlan.h>
+#include <linux/ip.h>
+#include <net/ip.h>
+#include <net/mpls.h>
+#include <linux/ipv6.h>
+#include <linux/in.h>
+#include <linux/jhash.h>
+#include <linux/random.h>
+#include <trace/events/napi.h>
+#include <trace/events/net.h>
+#include <trace/events/skb.h>
+#include <linux/pci.h>
+#include <linux/inetdevice.h>
+#include <linux/cpu_rmap.h>
+#include <linux/static_key.h>
+#include <linux/hashtable.h>
+#include <linux/vmalloc.h>
+#include <linux/if_macvlan.h>
+#include <linux/errqueue.h>
+#include <linux/hrtimer.h>
+
+#include "net-sysfs.h"
+
+/* Instead of increasing this, you should create a hash table. */
+#define MAX_GRO_SKBS 8
+
+/* This should be increased if a protocol with a bigger head is added. */
+#define GRO_MAX_HEAD (MAX_HEADER + 128)
+
+static DEFINE_SPINLOCK(ptype_lock);
+static DEFINE_SPINLOCK(offload_lock);
+struct list_head ptype_base[PTYPE_HASH_SIZE] __read_mostly;
+struct list_head ptype_all __read_mostly;	/* Taps */
+static struct list_head offload_base __read_mostly;
+
+static int netif_rx_internal(struct sk_buff *skb);
+static int call_netdevice_notifiers_info(unsigned long val,
+					 struct net_device *dev,
+					 struct netdev_notifier_info *info);
+
+/*
+ * The @dev_base_head list is protected by @dev_base_lock and the rtnl
+ * semaphore.
+ *
+ * Pure readers hold dev_base_lock for reading, or rcu_read_lock()
+ *
+ * Writers must hold the rtnl semaphore while they loop through the
+ * dev_base_head list, and hold dev_base_lock for writing when they do the
+ * actual updates.  This allows pure readers to access the list even
+ * while a writer is preparing to update it.
+ *
+ * To put it another way, dev_base_lock is held for writing only to
+ * protect against pure readers; the rtnl semaphore provides the
+ * protection against other writers.
+ *
+ * See, for example usages, register_netdevice() and
+ * unregister_netdevice(), which must be called with the rtnl
+ * semaphore held.
+ */
+DEFINE_RWLOCK(dev_base_lock);
+EXPORT_SYMBOL(dev_base_lock);
+
+/* protects napi_hash addition/deletion and napi_gen_id */
+static DEFINE_SPINLOCK(napi_hash_lock);
+
+static unsigned int napi_gen_id;
+static DEFINE_HASHTABLE(napi_hash, 8);
+
+static seqcount_t devnet_rename_seq;
+
+static inline void dev_base_seq_inc(struct net *net)
+{
+	while (++net->dev_base_seq == 0);
+}
+
+static inline struct hlist_head *dev_name_hash(struct net *net, const char *name)
+{
+	unsigned int hash = full_name_hash(name, strnlen(name, IFNAMSIZ));
+
+	return &net->dev_name_head[hash_32(hash, NETDEV_HASHBITS)];
+}
+
+static inline struct hlist_head *dev_index_hash(struct net *net, int ifindex)
+{
+	return &net->dev_index_head[ifindex & (NETDEV_HASHENTRIES - 1)];
+}
+
+static inline void rps_lock(struct softnet_data *sd)
+{
+#ifdef CONFIG_RPS
+	spin_lock(&sd->input_pkt_queue.lock);
+#endif
+}
+
+static inline void rps_unlock(struct softnet_data *sd)
+{
+#ifdef CONFIG_RPS
+	spin_unlock(&sd->input_pkt_queue.lock);
+#endif
+}
+
+/* Device list insertion */
+static void list_netdevice(struct net_device *dev)
+{
+	struct net *net = dev_net(dev);
+
+	ASSERT_RTNL();
+
+	write_lock_bh(&dev_base_lock);
+	list_add_tail_rcu(&dev->dev_list, &net->dev_base_head);
+	hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
+	hlist_add_head_rcu(&dev->index_hlist,
+			   dev_index_hash(net, dev->ifindex));
+	write_unlock_bh(&dev_base_lock);
+
+	dev_base_seq_inc(net);
+}
+
+/* Device list removal
+ * caller must respect a RCU grace period before freeing/reusing dev
+ */
+static void unlist_netdevice(struct net_device *dev)
+{
+	ASSERT_RTNL();
+
+	/* Unlink dev from the device chain */
+	write_lock_bh(&dev_base_lock);
+	list_del_rcu(&dev->dev_list);
+	hlist_del_rcu(&dev->name_hlist);
+	hlist_del_rcu(&dev->index_hlist);
+	write_unlock_bh(&dev_base_lock);
+
+	dev_base_seq_inc(dev_net(dev));
+}
+
+/*
+ *	Our notifier list
+ */
+
+static RAW_NOTIFIER_HEAD(netdev_chain);
+
+/*
+ *	Device drivers call our routines to queue packets here. We empty the
+ *	queue in the local softnet handler.
+ */
+
+DEFINE_PER_CPU_ALIGNED(struct softnet_data, softnet_data);
+EXPORT_PER_CPU_SYMBOL(softnet_data);
+
+#ifdef CONFIG_LOCKDEP
+/*
+ * register_netdevice() inits txq->_xmit_lock and sets lockdep class
+ * according to dev->type
+ */
+static const unsigned short netdev_lock_type[] =
+	{ARPHRD_NETROM, ARPHRD_ETHER, ARPHRD_EETHER, ARPHRD_AX25,
+	 ARPHRD_PRONET, ARPHRD_CHAOS, ARPHRD_IEEE802, ARPHRD_ARCNET,
+	 ARPHRD_APPLETLK, ARPHRD_DLCI, ARPHRD_ATM, ARPHRD_METRICOM,
+	 ARPHRD_IEEE1394, ARPHRD_EUI64, ARPHRD_INFINIBAND, ARPHRD_SLIP,
+	 ARPHRD_CSLIP, ARPHRD_SLIP6, ARPHRD_CSLIP6, ARPHRD_RSRVD,
+	 ARPHRD_ADAPT, ARPHRD_ROSE, ARPHRD_X25, ARPHRD_HWX25,
+	 ARPHRD_PPP, ARPHRD_CISCO, ARPHRD_LAPB, ARPHRD_DDCMP,
+	 ARPHRD_RAWHDLC, ARPHRD_TUNNEL, ARPHRD_TUNNEL6, ARPHRD_FRAD,
+	 ARPHRD_SKIP, ARPHRD_LOOPBACK, ARPHRD_LOCALTLK, ARPHRD_FDDI,
+	 ARPHRD_BIF, ARPHRD_SIT, ARPHRD_IPDDP, ARPHRD_IPGRE,
+	 ARPHRD_PIMREG, ARPHRD_HIPPI, ARPHRD_ASH, ARPHRD_ECONET,
+	 ARPHRD_IRDA, ARPHRD_FCPP, ARPHRD_FCAL, ARPHRD_FCPL,
+	 ARPHRD_FCFABRIC, ARPHRD_IEEE80211, ARPHRD_IEEE80211_PRISM,
+	 ARPHRD_IEEE80211_RADIOTAP, ARPHRD_PHONET, ARPHRD_PHONET_PIPE,
+	 ARPHRD_IEEE802154, ARPHRD_VOID, ARPHRD_NONE};
+
+static const char *const netdev_lock_name[] =
+	{"_xmit_NETROM", "_xmit_ETHER", "_xmit_EETHER", "_xmit_AX25",
+	 "_xmit_PRONET", "_xmit_CHAOS", "_xmit_IEEE802", "_xmit_ARCNET",
+	 "_xmit_APPLETLK", "_xmit_DLCI", "_xmit_ATM", "_xmit_METRICOM",
+	 "_xmit_IEEE1394", "_xmit_EUI64", "_xmit_INFINIBAND", "_xmit_SLIP",
+	 "_xmit_CSLIP", "_xmit_SLIP6", "_xmit_CSLIP6", "_xmit_RSRVD",
+	 "_xmit_ADAPT", "_xmit_ROSE", "_xmit_X25", "_xmit_HWX25",
+	 "_xmit_PPP", "_xmit_CISCO", "_xmit_LAPB", "_xmit_DDCMP",
+	 "_xmit_RAWHDLC", "_xmit_TUNNEL", "_xmit_TUNNEL6", "_xmit_FRAD",
+	 "_xmit_SKIP", "_xmit_LOOPBACK", "_xmit_LOCALTLK", "_xmit_FDDI",
+	 "_xmit_BIF", "_xmit_SIT", "_xmit_IPDDP", "_xmit_IPGRE",
+	 "_xmit_PIMREG", "_xmit_HIPPI", "_xmit_ASH", "_xmit_ECONET",
+	 "_xmit_IRDA", "_xmit_FCPP", "_xmit_FCAL", "_xmit_FCPL",
+	 "_xmit_FCFABRIC", "_xmit_IEEE80211", "_xmit_IEEE80211_PRISM",
+	 "_xmit_IEEE80211_RADIOTAP", "_xmit_PHONET", "_xmit_PHONET_PIPE",
+	 "_xmit_IEEE802154", "_xmit_VOID", "_xmit_NONE"};
+
+static struct lock_class_key netdev_xmit_lock_key[ARRAY_SIZE(netdev_lock_type)];
+static struct lock_class_key netdev_addr_lock_key[ARRAY_SIZE(netdev_lock_type)];
+
+static inline unsigned short netdev_lock_pos(unsigned short dev_type)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(netdev_lock_type); i++)
+		if (netdev_lock_type[i] == dev_type)
+			return i;
+	/* the last key is used by default */
+	return ARRAY_SIZE(netdev_lock_type) - 1;
+}
+
+static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
+						 unsigned short dev_type)
+{
+	int i;
+
+	i = netdev_lock_pos(dev_type);
+	lockdep_set_class_and_name(lock, &netdev_xmit_lock_key[i],
+				   netdev_lock_name[i]);
+}
+
+static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
+{
+	int i;
+
+	i = netdev_lock_pos(dev->type);
+	lockdep_set_class_and_name(&dev->addr_list_lock,
+				   &netdev_addr_lock_key[i],
+				   netdev_lock_name[i]);
+}
+#else
+static inline void netdev_set_xmit_lockdep_class(spinlock_t *lock,
+						 unsigned short dev_type)
+{
+}
+static inline void netdev_set_addr_lockdep_class(struct net_device *dev)
+{
+}
+#endif
+
+/*******************************************************************************
+
+		Protocol management and registration routines
+
+*******************************************************************************/
+
+/*
+ *	Add a protocol ID to the list. Now that the input handler is
+ *	smarter we can dispense with all the messy stuff that used to be
+ *	here.
+ *
+ *	BEWARE!!! Protocol handlers, mangling input packets,
+ *	MUST BE last in hash buckets and checking protocol handlers
+ *	MUST start from promiscuous ptype_all chain in net_bh.
+ *	It is true now, do not change it.
+ *	Explanation follows: if protocol handler, mangling packet, will
+ *	be the first on list, it is not able to sense, that packet
+ *	is cloned and should be copied-on-write, so that it will
+ *	change it and subsequent readers will get broken packet.
+ *							--ANK (980803)
+ */
+
+static inline struct list_head *ptype_head(const struct packet_type *pt)
+{
+	if (pt->type == htons(ETH_P_ALL))
+		return pt->dev ? &pt->dev->ptype_all : &ptype_all;
+	else
+		return pt->dev ? &pt->dev->ptype_specific :
+				 &ptype_base[ntohs(pt->type) & PTYPE_HASH_MASK];
+}
+
+/**
+ *	dev_add_pack - add packet handler
+ *	@pt: packet type declaration
+ *
+ *	Add a protocol handler to the networking stack. The passed &packet_type
+ *	is linked into kernel lists and may not be freed until it has been
+ *	removed from the kernel lists.
+ *
+ *	This call does not sleep therefore it can not
+ *	guarantee all CPU's that are in middle of receiving packets
+ *	will see the new packet type (until the next received packet).
+ */
+
+void dev_add_pack(struct packet_type *pt)
+{
+	struct list_head *head = ptype_head(pt);
+
+	spin_lock(&ptype_lock);
+	list_add_rcu(&pt->list, head);
+	spin_unlock(&ptype_lock);
+}
+EXPORT_SYMBOL(dev_add_pack);
+
+/**
+ *	__dev_remove_pack	 - remove packet handler
+ *	@pt: packet type declaration
+ *
+ *	Remove a protocol handler that was previously added to the kernel
+ *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
+ *	from the kernel lists and can be freed or reused once this function
+ *	returns.
+ *
+ *      The packet type might still be in use by receivers
+ *	and must not be freed until after all the CPU's have gone
+ *	through a quiescent state.
+ */
+void __dev_remove_pack(struct packet_type *pt)
+{
+	struct list_head *head = ptype_head(pt);
+	struct packet_type *pt1;
+
+	spin_lock(&ptype_lock);
+
+	list_for_each_entry(pt1, head, list) {
+		if (pt == pt1) {
+			list_del_rcu(&pt->list);
+			goto out;
+		}
+	}
+
+	pr_warn("dev_remove_pack: %p not found\n", pt);
+out:
+	spin_unlock(&ptype_lock);
+}
+EXPORT_SYMBOL(__dev_remove_pack);
+
+/**
+ *	dev_remove_pack	 - remove packet handler
+ *	@pt: packet type declaration
+ *
+ *	Remove a protocol handler that was previously added to the kernel
+ *	protocol handlers by dev_add_pack(). The passed &packet_type is removed
+ *	from the kernel lists and can be freed or reused once this function
+ *	returns.
+ *
+ *	This call sleeps to guarantee that no CPU is looking at the packet
+ *	type after return.
+ */
+void dev_remove_pack(struct packet_type *pt)
+{
+	__dev_remove_pack(pt);
+
+	synchronize_net();
+}
+EXPORT_SYMBOL(dev_remove_pack);
+
+
+/**
+ *	dev_add_offload - register offload handlers
+ *	@po: protocol offload declaration
+ *
+ *	Add protocol offload handlers to the networking stack. The passed
+ *	&proto_offload is linked into kernel lists and may not be freed until
+ *	it has been removed from the kernel lists.
+ *
+ *	This call does not sleep therefore it can not
+ *	guarantee all CPU's that are in middle of receiving packets
+ *	will see the new offload handlers (until the next received packet).
+ */
+void dev_add_offload(struct packet_offload *po)
+{
+	struct list_head *head = &offload_base;
+
+	spin_lock(&offload_lock);
+	list_add_rcu(&po->list, head);
+	spin_unlock(&offload_lock);
+}
+EXPORT_SYMBOL(dev_add_offload);
+
+/**
+ *	__dev_remove_offload	 - remove offload handler
+ *	@po: packet offload declaration
+ *
+ *	Remove a protocol offload handler that was previously added to the
+ *	kernel offload handlers by dev_add_offload(). The passed &offload_type
+ *	is removed from the kernel lists and can be freed or reused once this
+ *	function returns.
+ *
+ *      The packet type might still be in use by receivers
+ *	and must not be freed until after all the CPU's have gone
+ *	through a quiescent state.
+ */
+static void __dev_remove_offload(struct packet_offload *po)
+{
+	struct list_head *head = &offload_base;
+	struct packet_offload *po1;
+
+	spin_lock(&offload_lock);
+
+	list_for_each_entry(po1, head, list) {
+		if (po == po1) {
+			list_del_rcu(&po->list);
+			goto out;
+		}
+	}
+
+	pr_warn("dev_remove_offload: %p not found\n", po);
+out:
+	spin_unlock(&offload_lock);
+}
+
+/**
+ *	dev_remove_offload	 - remove packet offload handler
+ *	@po: packet offload declaration
+ *
+ *	Remove a packet offload handler that was previously added to the kernel
+ *	offload handlers by dev_add_offload(). The passed &offload_type is
+ *	removed from the kernel lists and can be freed or reused once this
+ *	function returns.
+ *
+ *	This call sleeps to guarantee that no CPU is looking at the packet
+ *	type after return.
+ */
+void dev_remove_offload(struct packet_offload *po)
+{
+	__dev_remove_offload(po);
+
+	synchronize_net();
+}
+EXPORT_SYMBOL(dev_remove_offload);
+
+/******************************************************************************
+
+		      Device Boot-time Settings Routines
+
+*******************************************************************************/
+
+/* Boot time configuration table */
+static struct netdev_boot_setup dev_boot_setup[NETDEV_BOOT_SETUP_MAX];
+
+/**
+ *	netdev_boot_setup_add	- add new setup entry
+ *	@name: name of the device
+ *	@map: configured settings for the device
+ *
+ *	Adds new setup entry to the dev_boot_setup list.  The function
+ *	returns 0 on error and 1 on success.  This is a generic routine to
+ *	all netdevices.
+ */
+static int netdev_boot_setup_add(char *name, struct ifmap *map)
+{
+	struct netdev_boot_setup *s;
+	int i;
+
+	s = dev_boot_setup;
+	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
+		if (s[i].name[0] == '\0' || s[i].name[0] == ' ') {
+			memset(s[i].name, 0, sizeof(s[i].name));
+			strlcpy(s[i].name, name, IFNAMSIZ);
+			memcpy(&s[i].map, map, sizeof(s[i].map));
+			break;
+		}
+	}
+
+	return i >= NETDEV_BOOT_SETUP_MAX ? 0 : 1;
+}
+
+/**
+ *	netdev_boot_setup_check	- check boot time settings
+ *	@dev: the netdevice
+ *
+ * 	Check boot time settings for the device.
+ *	The found settings are set for the device to be used
+ *	later in the device probing.
+ *	Returns 0 if no settings found, 1 if they are.
+ */
+int netdev_boot_setup_check(struct net_device *dev)
+{
+	struct netdev_boot_setup *s = dev_boot_setup;
+	int i;
+
+	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++) {
+		if (s[i].name[0] != '\0' && s[i].name[0] != ' ' &&
+		    !strcmp(dev->name, s[i].name)) {
+			dev->irq 	= s[i].map.irq;
+			dev->base_addr 	= s[i].map.base_addr;
+			dev->mem_start 	= s[i].map.mem_start;
+			dev->mem_end 	= s[i].map.mem_end;
+			return 1;
+		}
+	}
+	return 0;
+}
+EXPORT_SYMBOL(netdev_boot_setup_check);
+
+
+/**
+ *	netdev_boot_base	- get address from boot time settings
+ *	@prefix: prefix for network device
+ *	@unit: id for network device
+ *
+ * 	Check boot time settings for the base address of device.
+ *	The found settings are set for the device to be used
+ *	later in the device probing.
+ *	Returns 0 if no settings found.
+ */
+unsigned long netdev_boot_base(const char *prefix, int unit)
+{
+	const struct netdev_boot_setup *s = dev_boot_setup;
+	char name[IFNAMSIZ];
+	int i;
+
+	sprintf(name, "%s%d", prefix, unit);
+
+	/*
+	 * If device already registered then return base of 1
+	 * to indicate not to probe for this interface
+	 */
+	if (__dev_get_by_name(&init_net, name))
+		return 1;
+
+	for (i = 0; i < NETDEV_BOOT_SETUP_MAX; i++)
+		if (!strcmp(name, s[i].name))
+			return s[i].map.base_addr;
+	return 0;
+}
+
+/*
+ * Saves at boot time configured settings for any netdevice.
+ */
+int __init netdev_boot_setup(char *str)
+{
+	int ints[5];
+	struct ifmap map;
+
+	str = get_options(str, ARRAY_SIZE(ints), ints);
+	if (!str || !*str)
+		return 0;
+
+	/* Save settings */
+	memset(&map, 0, sizeof(map));
+	if (ints[0] > 0)
+		map.irq = ints[1];
+	if (ints[0] > 1)
+		map.base_addr = ints[2];
+	if (ints[0] > 2)
+		map.mem_start = ints[3];
+	if (ints[0] > 3)
+		map.mem_end = ints[4];
+
+	/* Add new entry to the list */
+	return netdev_boot_setup_add(str, &map);
+}
+
+__setup("netdev=", netdev_boot_setup);
+
+/*******************************************************************************
+
+			    Device Interface Subroutines
+
+*******************************************************************************/
+
+/**
+ *	dev_get_iflink	- get 'iflink' value of a interface
+ *	@dev: targeted interface
+ *
+ *	Indicates the ifindex the interface is linked to.
+ *	Physical interfaces have the same 'ifindex' and 'iflink' values.
+ */
+
+int dev_get_iflink(const struct net_device *dev)
+{
+	if (dev->netdev_ops && dev->netdev_ops->ndo_get_iflink)
+		return dev->netdev_ops->ndo_get_iflink(dev);
+
+	/* If dev->rtnl_link_ops is set, it's a virtual interface. */
+	if (dev->rtnl_link_ops)
+		return 0;
+
+	return dev->ifindex;
+}
+EXPORT_SYMBOL(dev_get_iflink);
+
+/**
+ *	__dev_get_by_name	- find a device by its name
+ *	@net: the applicable net namespace
+ *	@name: name to find
+ *
+ *	Find an interface by name. Must be called under RTNL semaphore
+ *	or @dev_base_lock. If the name is found a pointer to the device
+ *	is returned. If the name is not found then %NULL is returned. The
+ *	reference counters are not incremented so the caller must be
+ *	careful with locks.
+ */
+
+struct net_device *__dev_get_by_name(struct net *net, const char *name)
+{
+	struct net_device *dev;
+	struct hlist_head *head = dev_name_hash(net, name);
+
+	hlist_for_each_entry(dev, head, name_hlist)
+		if (!strncmp(dev->name, name, IFNAMSIZ))
+			return dev;
+
+	return NULL;
+}
+EXPORT_SYMBOL(__dev_get_by_name);
+
+/**
+ *	dev_get_by_name_rcu	- find a device by its name
+ *	@net: the applicable net namespace
+ *	@name: name to find
+ *
+ *	Find an interface by name.
+ *	If the name is found a pointer to the device is returned.
+ * 	If the name is not found then %NULL is returned.
+ *	The reference counters are not incremented so the caller must be
+ *	careful with locks. The caller must hold RCU lock.
+ */
+
+struct net_device *dev_get_by_name_rcu(struct net *net, const char *name)
+{
+	struct net_device *dev;
+	struct hlist_head *head = dev_name_hash(net, name);
+
+	hlist_for_each_entry_rcu(dev, head, name_hlist)
+		if (!strncmp(dev->name, name, IFNAMSIZ))
+			return dev;
+
+	return NULL;
+}
+EXPORT_SYMBOL(dev_get_by_name_rcu);
+
+/**
+ *	dev_get_by_name		- find a device by its name
+ *	@net: the applicable net namespace
+ *	@name: name to find
+ *
+ *	Find an interface by name. This can be called from any
+ *	context and does its own locking. The returned handle has
+ *	the usage count incremented and the caller must use dev_put() to
+ *	release it when it is no longer needed. %NULL is returned if no
+ *	matching device is found.
+ */
+
+struct net_device *dev_get_by_name(struct net *net, const char *name)
+{
+	struct net_device *dev;
+
+	rcu_read_lock();
+	dev = dev_get_by_name_rcu(net, name);
+	if (dev)
+		dev_hold(dev);
+	rcu_read_unlock();
+	return dev;
+}
+EXPORT_SYMBOL(dev_get_by_name);
+
+/**
+ *	__dev_get_by_index - find a device by its ifindex
+ *	@net: the applicable net namespace
+ *	@ifindex: index of device
+ *
+ *	Search for an interface by index. Returns %NULL if the device
+ *	is not found or a pointer to the device. The device has not
+ *	had its reference counter increased so the caller must be careful
+ *	about locking. The caller must hold either the RTNL semaphore
+ *	or @dev_base_lock.
+ */
+
+struct net_device *__dev_get_by_index(struct net *net, int ifindex)
+{
+	struct net_device *dev;
+	struct hlist_head *head = dev_index_hash(net, ifindex);
+
+	hlist_for_each_entry(dev, head, index_hlist)
+		if (dev->ifindex == ifindex)
+			return dev;
+
+	return NULL;
+}
+EXPORT_SYMBOL(__dev_get_by_index);
+
+/**
+ *	dev_get_by_index_rcu - find a device by its ifindex
+ *	@net: the applicable net namespace
+ *	@ifindex: index of device
+ *
+ *	Search for an interface by index. Returns %NULL if the device
+ *	is not found or a pointer to the device. The device has not
+ *	had its reference counter increased so the caller must be careful
+ *	about locking. The caller must hold RCU lock.
+ */
+
+struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex)
+{
+	struct net_device *dev;
+	struct hlist_head *head = dev_index_hash(net, ifindex);
+
+	hlist_for_each_entry_rcu(dev, head, index_hlist)
+		if (dev->ifindex == ifindex)
+			return dev;
+
+	return NULL;
+}
+EXPORT_SYMBOL(dev_get_by_index_rcu);
+
+
+/**
+ *	dev_get_by_index - find a device by its ifindex
+ *	@net: the applicable net namespace
+ *	@ifindex: index of device
+ *
+ *	Search for an interface by index. Returns NULL if the device
+ *	is not found or a pointer to the device. The device returned has
+ *	had a reference added and the pointer is safe until the user calls
+ *	dev_put to indicate they have finished with it.
+ */
+
+struct net_device *dev_get_by_index(struct net *net, int ifindex)
+{
+	struct net_device *dev;
+
+	rcu_read_lock();
+	dev = dev_get_by_index_rcu(net, ifindex);
+	if (dev)
+		dev_hold(dev);
+	rcu_read_unlock();
+	return dev;
+}
+EXPORT_SYMBOL(dev_get_by_index);
+
+/**
+ *	netdev_get_name - get a netdevice name, knowing its ifindex.
+ *	@net: network namespace
+ *	@name: a pointer to the buffer where the name will be stored.
+ *	@ifindex: the ifindex of the interface to get the name from.
+ *
+ *	The use of raw_seqcount_begin() and cond_resched() before
+ *	retrying is required as we want to give the writers a chance
+ *	to complete when CONFIG_PREEMPT is not set.
+ */
+int netdev_get_name(struct net *net, char *name, int ifindex)
+{
+	struct net_device *dev;
+	unsigned int seq;
+
+retry:
+	seq = raw_seqcount_begin(&devnet_rename_seq);
+	rcu_read_lock();
+	dev = dev_get_by_index_rcu(net, ifindex);
+	if (!dev) {
+		rcu_read_unlock();
+		return -ENODEV;
+	}
+
+	strcpy(name, dev->name);
+	rcu_read_unlock();
+	if (read_seqcount_retry(&devnet_rename_seq, seq)) {
+		cond_resched();
+		goto retry;
+	}
+
+	return 0;
+}
+
+/**
+ *	dev_getbyhwaddr_rcu - find a device by its hardware address
+ *	@net: the applicable net namespace
+ *	@type: media type of device
+ *	@ha: hardware address
+ *
+ *	Search for an interface by MAC address. Returns NULL if the device
+ *	is not found or a pointer to the device.
+ *	The caller must hold RCU or RTNL.
+ *	The returned device has not had its ref count increased
+ *	and the caller must therefore be careful about locking
+ *
+ */
+
+struct net_device *dev_getbyhwaddr_rcu(struct net *net, unsigned short type,
+				       const char *ha)
+{
+	struct net_device *dev;
+
+	for_each_netdev_rcu(net, dev)
+		if (dev->type == type &&
+		    !memcmp(dev->dev_addr, ha, dev->addr_len))
+			return dev;
+
+	return NULL;
+}
+EXPORT_SYMBOL(dev_getbyhwaddr_rcu);
+
+struct net_device *__dev_getfirstbyhwtype(struct net *net, unsigned short type)
+{
+	struct net_device *dev;
+
+	ASSERT_RTNL();
+	for_each_netdev(net, dev)
+		if (dev->type == type)
+			return dev;
+
+	return NULL;
+}
+EXPORT_SYMBOL(__dev_getfirstbyhwtype);
+
+struct net_device *dev_getfirstbyhwtype(struct net *net, unsigned short type)
+{
+	struct net_device *dev, *ret = NULL;
+
+	rcu_read_lock();
+	for_each_netdev_rcu(net, dev)
+		if (dev->type == type) {
+			dev_hold(dev);
+			ret = dev;
+			break;
+		}
+	rcu_read_unlock();
+	return ret;
+}
+EXPORT_SYMBOL(dev_getfirstbyhwtype);
+
+/**
+ *	__dev_get_by_flags - find any device with given flags
+ *	@net: the applicable net namespace
+ *	@if_flags: IFF_* values
+ *	@mask: bitmask of bits in if_flags to check
+ *
+ *	Search for any interface with the given flags. Returns NULL if a device
+ *	is not found or a pointer to the device. Must be called inside
+ *	rtnl_lock(), and result refcount is unchanged.
+ */
+
+struct net_device *__dev_get_by_flags(struct net *net, unsigned short if_flags,
+				      unsigned short mask)
+{
+	struct net_device *dev, *ret;
+
+	ASSERT_RTNL();
+
+	ret = NULL;
+	for_each_netdev(net, dev) {
+		if (((dev->flags ^ if_flags) & mask) == 0) {
+			ret = dev;
+			break;
+		}
+	}
+	return ret;
+}
+EXPORT_SYMBOL(__dev_get_by_flags);
+
+/**
+ *	dev_valid_name - check if name is okay for network device
+ *	@name: name string
+ *
+ *	Network device names need to be valid file names to
+ *	to allow sysfs to work.  We also disallow any kind of
+ *	whitespace.
+ */
+bool dev_valid_name(const char *name)
+{
+	if (*name == '\0')
+		return false;
+	if (strlen(name) >= IFNAMSIZ)
+		return false;
+	if (!strcmp(name, ".") || !strcmp(name, ".."))
+		return false;
+
+	while (*name) {
+		if (*name == '/' || *name == ':' || isspace(*name))
+			return false;
+		name++;
+	}
+	return true;
+}
+EXPORT_SYMBOL(dev_valid_name);
+
+/**
+ *	__dev_alloc_name - allocate a name for a device
+ *	@net: network namespace to allocate the device name in
+ *	@name: name format string
+ *	@buf:  scratch buffer and result name string
+ *
+ *	Passed a format string - eg "lt%d" it will try and find a suitable
+ *	id. It scans list of devices to build up a free map, then chooses
+ *	the first empty slot. The caller must hold the dev_base or rtnl lock
+ *	while allocating the name and adding the device in order to avoid
+ *	duplicates.
+ *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
+ *	Returns the number of the unit assigned or a negative errno code.
+ */
+
+static int __dev_alloc_name(struct net *net, const char *name, char *buf)
+{
+	int i = 0;
+	const char *p;
+	const int max_netdevices = 8*PAGE_SIZE;
+	unsigned long *inuse;
+	struct net_device *d;
+
+	p = strnchr(name, IFNAMSIZ-1, '%');
+	if (p) {
+		/*
+		 * Verify the string as this thing may have come from
+		 * the user.  There must be either one "%d" and no other "%"
+		 * characters.
+		 */
+		if (p[1] != 'd' || strchr(p + 2, '%'))
+			return -EINVAL;
+
+		/* Use one page as a bit array of possible slots */
+		inuse = (unsigned long *) get_zeroed_page(GFP_ATOMIC);
+		if (!inuse)
+			return -ENOMEM;
+
+		for_each_netdev(net, d) {
+			if (!sscanf(d->name, name, &i))
+				continue;
+			if (i < 0 || i >= max_netdevices)
+				continue;
+
+			/*  avoid cases where sscanf is not exact inverse of printf */
+			snprintf(buf, IFNAMSIZ, name, i);
+			if (!strncmp(buf, d->name, IFNAMSIZ))
+				set_bit(i, inuse);
+		}
+
+		i = find_first_zero_bit(inuse, max_netdevices);
+		free_page((unsigned long) inuse);
+	}
+
+	if (buf != name)
+		snprintf(buf, IFNAMSIZ, name, i);
+	if (!__dev_get_by_name(net, buf))
+		return i;
+
+	/* It is possible to run out of possible slots
+	 * when the name is long and there isn't enough space left
+	 * for the digits, or if all bits are used.
+	 */
+	return -ENFILE;
+}
+
+/**
+ *	dev_alloc_name - allocate a name for a device
+ *	@dev: device
+ *	@name: name format string
+ *
+ *	Passed a format string - eg "lt%d" it will try and find a suitable
+ *	id. It scans list of devices to build up a free map, then chooses
+ *	the first empty slot. The caller must hold the dev_base or rtnl lock
+ *	while allocating the name and adding the device in order to avoid
+ *	duplicates.
+ *	Limited to bits_per_byte * page size devices (ie 32K on most platforms).
+ *	Returns the number of the unit assigned or a negative errno code.
+ */
+
+int dev_alloc_name(struct net_device *dev, const char *name)
+{
+	char buf[IFNAMSIZ];
+	struct net *net;
+	int ret;
+
+	BUG_ON(!dev_net(dev));
+	net = dev_net(dev);
+	ret = __dev_alloc_name(net, name, buf);
+	if (ret >= 0)
+		strlcpy(dev->name, buf, IFNAMSIZ);
+	return ret;
+}
+EXPORT_SYMBOL(dev_alloc_name);
+
+static int dev_alloc_name_ns(struct net *net,
+			     struct net_device *dev,
+			     const char *name)
+{
+	char buf[IFNAMSIZ];
+	int ret;
+
+	ret = __dev_alloc_name(net, name, buf);
+	if (ret >= 0)
+		strlcpy(dev->name, buf, IFNAMSIZ);
+	return ret;
+}
+
+static int dev_get_valid_name(struct net *net,
+			      struct net_device *dev,
+			      const char *name)
+{
+	BUG_ON(!net);
+
+	if (!dev_valid_name(name))
+		return -EINVAL;
+
+	if (strchr(name, '%'))
+		return dev_alloc_name_ns(net, dev, name);
+	else if (__dev_get_by_name(net, name))
+		return -EEXIST;
+	else if (dev->name != name)
+		strlcpy(dev->name, name, IFNAMSIZ);
+
+	return 0;
+}
+
+/**
+ *	dev_change_name - change name of a device
+ *	@dev: device
+ *	@newname: name (or format string) must be at least IFNAMSIZ
+ *
+ *	Change name of a device, can pass format strings "eth%d".
+ *	for wildcarding.
+ */
+int dev_change_name(struct net_device *dev, const char *newname)
+{
+	unsigned char old_assign_type;
+	char oldname[IFNAMSIZ];
+	int err = 0;
+	int ret;
+	struct net *net;
+
+	ASSERT_RTNL();
+	BUG_ON(!dev_net(dev));
+
+	net = dev_net(dev);
+	if (dev->flags & IFF_UP)
+		return -EBUSY;
+
+	write_seqcount_begin(&devnet_rename_seq);
+
+	if (strncmp(newname, dev->name, IFNAMSIZ) == 0) {
+		write_seqcount_end(&devnet_rename_seq);
+		return 0;
+	}
+
+	memcpy(oldname, dev->name, IFNAMSIZ);
+
+	err = dev_get_valid_name(net, dev, newname);
+	if (err < 0) {
+		write_seqcount_end(&devnet_rename_seq);
+		return err;
+	}
+
+	if (oldname[0] && !strchr(oldname, '%'))
+		netdev_info(dev, "renamed from %s\n", oldname);
+
+	old_assign_type = dev->name_assign_type;
+	dev->name_assign_type = NET_NAME_RENAMED;
+
+rollback:
+	ret = device_rename(&dev->dev, dev->name);
+	if (ret) {
+		memcpy(dev->name, oldname, IFNAMSIZ);
+		dev->name_assign_type = old_assign_type;
+		write_seqcount_end(&devnet_rename_seq);
+		return ret;
+	}
+
+	write_seqcount_end(&devnet_rename_seq);
+
+	netdev_adjacent_rename_links(dev, oldname);
+
+	write_lock_bh(&dev_base_lock);
+	hlist_del_rcu(&dev->name_hlist);
+	write_unlock_bh(&dev_base_lock);
+
+	synchronize_rcu();
+
+	write_lock_bh(&dev_base_lock);
+	hlist_add_head_rcu(&dev->name_hlist, dev_name_hash(net, dev->name));
+	write_unlock_bh(&dev_base_lock);
+
+	ret = call_netdevice_notifiers(NETDEV_CHANGENAME, dev);
+	ret = notifier_to_errno(ret);
+
+	if (ret) {
+		/* err >= 0 after dev_alloc_name() or stores the first errno */
+		if (err >= 0) {
+			err = ret;
+			write_seqcount_begin(&devnet_rename_seq);
+			memcpy(dev->name, oldname, IFNAMSIZ);
+			memcpy(oldname, newname, IFNAMSIZ);
+			dev->name_assign_type = old_assign_type;
+			old_assign_type = NET_NAME_RENAMED;
+			goto rollback;
+		} else {
+			pr_err("%s: name change rollback failed: %d\n",
+			       dev->name, ret);
+		}
+	}
+
+	return err;
+}
+
+/**
+ *	dev_set_alias - change ifalias of a device
+ *	@dev: device
+ *	@alias: name up to IFALIASZ
+ *	@len: limit of bytes to copy from info
+ *
+ *	Set ifalias for a device,
+ */
+int dev_set_alias(struct net_device *dev, const char *alias, size_t len)
+{
+	char *new_ifalias;
+
+	ASSERT_RTNL();
+
+	if (len >= IFALIASZ)
+		return -EINVAL;
+
+	if (!len) {
+		kfree(dev->ifalias);
+		dev->ifalias = NULL;
+		return 0;
+	}
+
+	new_ifalias = krealloc(dev->ifalias, len + 1, GFP_KERNEL);
+	if (!new_ifalias)
+		return -ENOMEM;
+	dev->ifalias = new_ifalias;
+
+	strlcpy(dev->ifalias, alias, len+1);
+	return len;
+}
+
+
+/**
+ *	netdev_features_change - device changes features
+ *	@dev: device to cause notification
+ *
+ *	Called to indicate a device has changed features.
+ */
+void netdev_features_change(struct net_device *dev)
+{
+	call_netdevice_notifiers(NETDEV_FEAT_CHANGE, dev);
+}
+EXPORT_SYMBOL(netdev_features_change);
+
+/**
+ *	netdev_state_change - device changes state
+ *	@dev: device to cause notification
+ *
+ *	Called to indicate a device has changed state. This function calls
+ *	the notifier chains for netdev_chain and sends a NEWLINK message
+ *	to the routing socket.
+ */
+void netdev_state_change(struct net_device *dev)
+{
+	if (dev->flags & IFF_UP) {
+		struct netdev_notifier_change_info change_info;
+
+		change_info.flags_changed = 0;
+		call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
+					      &change_info.info);
+		rtmsg_ifinfo(RTM_NEWLINK, dev, 0, GFP_KERNEL);
+	}
+}
+EXPORT_SYMBOL(netdev_state_change);
+
+/**
+ * 	netdev_notify_peers - notify network peers about existence of @dev
+ * 	@dev: network device
+ *
+ * Generate traffic such that interested network peers are aware of
+ * @dev, such as by generating a gratuitous ARP. This may be used when
+ * a device wants to inform the rest of the network about some sort of
+ * reconfiguration such as a failover event or virtual machine
+ * migration.
+ */
+void netdev_notify_peers(struct net_device *dev)
+{
+	rtnl_lock();
+	call_netdevice_notifiers(NETDEV_NOTIFY_PEERS, dev);
+	rtnl_unlock();
+}
+EXPORT_SYMBOL(netdev_notify_peers);
+
+static int __dev_open(struct net_device *dev)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+	int ret;
+
+	ASSERT_RTNL();
+
+	if (!netif_device_present(dev))
+		return -ENODEV;
+
+	/* Block netpoll from trying to do any rx path servicing.
+	 * If we don't do this there is a chance ndo_poll_controller
+	 * or ndo_poll may be running while we open the device
+	 */
+	netpoll_poll_disable(dev);
+
+	ret = call_netdevice_notifiers(NETDEV_PRE_UP, dev);
+	ret = notifier_to_errno(ret);
+	if (ret)
+		return ret;
+
+	set_bit(__LINK_STATE_START, &dev->state);
+
+	if (ops->ndo_validate_addr)
+		ret = ops->ndo_validate_addr(dev);
+
+	if (!ret && ops->ndo_open)
+		ret = ops->ndo_open(dev);
+
+	netpoll_poll_enable(dev);
+
+	if (ret)
+		clear_bit(__LINK_STATE_START, &dev->state);
+	else {
+		dev->flags |= IFF_UP;
+		dev_set_rx_mode(dev);
+		dev_activate(dev);
+		add_device_randomness(dev->dev_addr, dev->addr_len);
+	}
+
+	return ret;
+}
+
+/**
+ *	dev_open	- prepare an interface for use.
+ *	@dev:	device to open
+ *
+ *	Takes a device from down to up state. The device's private open
+ *	function is invoked and then the multicast lists are loaded. Finally
+ *	the device is moved into the up state and a %NETDEV_UP message is
+ *	sent to the netdev notifier chain.
+ *
+ *	Calling this function on an active interface is a nop. On a failure
+ *	a negative errno code is returned.
+ */
+int dev_open(struct net_device *dev)
+{
+	int ret;
+
+	if (dev->flags & IFF_UP)
+		return 0;
+
+	ret = __dev_open(dev);
+	if (ret < 0)
+		return ret;
+
+	rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
+	call_netdevice_notifiers(NETDEV_UP, dev);
+
+	return ret;
+}
+EXPORT_SYMBOL(dev_open);
+
+static int __dev_close_many(struct list_head *head)
+{
+	struct net_device *dev;
+
+	ASSERT_RTNL();
+	might_sleep();
+
+	list_for_each_entry(dev, head, close_list) {
+		/* Temporarily disable netpoll until the interface is down */
+		netpoll_poll_disable(dev);
+
+		call_netdevice_notifiers(NETDEV_GOING_DOWN, dev);
+
+		clear_bit(__LINK_STATE_START, &dev->state);
+
+		/* Synchronize to scheduled poll. We cannot touch poll list, it
+		 * can be even on different cpu. So just clear netif_running().
+		 *
+		 * dev->stop() will invoke napi_disable() on all of it's
+		 * napi_struct instances on this device.
+		 */
+		smp_mb__after_atomic(); /* Commit netif_running(). */
+	}
+
+	dev_deactivate_many(head);
+
+	list_for_each_entry(dev, head, close_list) {
+		const struct net_device_ops *ops = dev->netdev_ops;
+
+		/*
+		 *	Call the device specific close. This cannot fail.
+		 *	Only if device is UP
+		 *
+		 *	We allow it to be called even after a DETACH hot-plug
+		 *	event.
+		 */
+		if (ops->ndo_stop)
+			ops->ndo_stop(dev);
+
+		dev->flags &= ~IFF_UP;
+		netpoll_poll_enable(dev);
+	}
+
+	return 0;
+}
+
+static int __dev_close(struct net_device *dev)
+{
+	int retval;
+	LIST_HEAD(single);
+
+	list_add(&dev->close_list, &single);
+	retval = __dev_close_many(&single);
+	list_del(&single);
+
+	return retval;
+}
+
+int dev_close_many(struct list_head *head, bool unlink)
+{
+	struct net_device *dev, *tmp;
+
+	/* Remove the devices that don't need to be closed */
+	list_for_each_entry_safe(dev, tmp, head, close_list)
+		if (!(dev->flags & IFF_UP))
+			list_del_init(&dev->close_list);
+
+	__dev_close_many(head);
+
+	list_for_each_entry_safe(dev, tmp, head, close_list) {
+		rtmsg_ifinfo(RTM_NEWLINK, dev, IFF_UP|IFF_RUNNING, GFP_KERNEL);
+		call_netdevice_notifiers(NETDEV_DOWN, dev);
+		if (unlink)
+			list_del_init(&dev->close_list);
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL(dev_close_many);
+
+/**
+ *	dev_close - shutdown an interface.
+ *	@dev: device to shutdown
+ *
+ *	This function moves an active device into down state. A
+ *	%NETDEV_GOING_DOWN is sent to the netdev notifier chain. The device
+ *	is then deactivated and finally a %NETDEV_DOWN is sent to the notifier
+ *	chain.
+ */
+int dev_close(struct net_device *dev)
+{
+	if (dev->flags & IFF_UP) {
+		LIST_HEAD(single);
+
+		list_add(&dev->close_list, &single);
+		dev_close_many(&single, true);
+		list_del(&single);
+	}
+	return 0;
+}
+EXPORT_SYMBOL(dev_close);
+
+
+/**
+ *	dev_disable_lro - disable Large Receive Offload on a device
+ *	@dev: device
+ *
+ *	Disable Large Receive Offload (LRO) on a net device.  Must be
+ *	called under RTNL.  This is needed if received packets may be
+ *	forwarded to another interface.
+ */
+void dev_disable_lro(struct net_device *dev)
+{
+	struct net_device *lower_dev;
+	struct list_head *iter;
+
+	dev->wanted_features &= ~NETIF_F_LRO;
+	netdev_update_features(dev);
+
+	if (unlikely(dev->features & NETIF_F_LRO))
+		netdev_WARN(dev, "failed to disable LRO!\n");
+
+	netdev_for_each_lower_dev(dev, lower_dev, iter)
+		dev_disable_lro(lower_dev);
+}
+EXPORT_SYMBOL(dev_disable_lro);
+
+static int call_netdevice_notifier(struct notifier_block *nb, unsigned long val,
+				   struct net_device *dev)
+{
+	struct netdev_notifier_info info;
+
+	netdev_notifier_info_init(&info, dev);
+	return nb->notifier_call(nb, val, &info);
+}
+
+static int dev_boot_phase = 1;
+
+/**
+ *	register_netdevice_notifier - register a network notifier block
+ *	@nb: notifier
+ *
+ *	Register a notifier to be called when network device events occur.
+ *	The notifier passed is linked into the kernel structures and must
+ *	not be reused until it has been unregistered. A negative errno code
+ *	is returned on a failure.
+ *
+ * 	When registered all registration and up events are replayed
+ *	to the new notifier to allow device to have a race free
+ *	view of the network device list.
+ */
+
+int register_netdevice_notifier(struct notifier_block *nb)
+{
+	struct net_device *dev;
+	struct net_device *last;
+	struct net *net;
+	int err;
+
+	rtnl_lock();
+	err = raw_notifier_chain_register(&netdev_chain, nb);
+	if (err)
+		goto unlock;
+	if (dev_boot_phase)
+		goto unlock;
+	for_each_net(net) {
+		for_each_netdev(net, dev) {
+			err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
+			err = notifier_to_errno(err);
+			if (err)
+				goto rollback;
+
+			if (!(dev->flags & IFF_UP))
+				continue;
+
+			call_netdevice_notifier(nb, NETDEV_UP, dev);
+		}
+	}
+
+unlock:
+	rtnl_unlock();
+	return err;
+
+rollback:
+	last = dev;
+	for_each_net(net) {
+		for_each_netdev(net, dev) {
+			if (dev == last)
+				goto outroll;
+
+			if (dev->flags & IFF_UP) {
+				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
+							dev);
+				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
+			}
+			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
+		}
+	}
+
+outroll:
+	raw_notifier_chain_unregister(&netdev_chain, nb);
+	goto unlock;
+}
+EXPORT_SYMBOL(register_netdevice_notifier);
+
+/**
+ *	unregister_netdevice_notifier - unregister a network notifier block
+ *	@nb: notifier
+ *
+ *	Unregister a notifier previously registered by
+ *	register_netdevice_notifier(). The notifier is unlinked into the
+ *	kernel structures and may then be reused. A negative errno code
+ *	is returned on a failure.
+ *
+ * 	After unregistering unregister and down device events are synthesized
+ *	for all devices on the device list to the removed notifier to remove
+ *	the need for special case cleanup code.
+ */
+
+int unregister_netdevice_notifier(struct notifier_block *nb)
+{
+	struct net_device *dev;
+	struct net *net;
+	int err;
+
+	rtnl_lock();
+	err = raw_notifier_chain_unregister(&netdev_chain, nb);
+	if (err)
+		goto unlock;
+
+	for_each_net(net) {
+		for_each_netdev(net, dev) {
+			if (dev->flags & IFF_UP) {
+				call_netdevice_notifier(nb, NETDEV_GOING_DOWN,
+							dev);
+				call_netdevice_notifier(nb, NETDEV_DOWN, dev);
+			}
+			call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
+		}
+	}
+unlock:
+	rtnl_unlock();
+	return err;
+}
+EXPORT_SYMBOL(unregister_netdevice_notifier);
+
+/**
+ *	call_netdevice_notifiers_info - call all network notifier blocks
+ *	@val: value passed unmodified to notifier function
+ *	@dev: net_device pointer passed unmodified to notifier function
+ *	@info: notifier information data
+ *
+ *	Call all network notifier blocks.  Parameters and return value
+ *	are as for raw_notifier_call_chain().
+ */
+
+static int call_netdevice_notifiers_info(unsigned long val,
+					 struct net_device *dev,
+					 struct netdev_notifier_info *info)
+{
+	ASSERT_RTNL();
+	netdev_notifier_info_init(info, dev);
+	return raw_notifier_call_chain(&netdev_chain, val, info);
+}
+
+/**
+ *	call_netdevice_notifiers - call all network notifier blocks
+ *      @val: value passed unmodified to notifier function
+ *      @dev: net_device pointer passed unmodified to notifier function
+ *
+ *	Call all network notifier blocks.  Parameters and return value
+ *	are as for raw_notifier_call_chain().
+ */
+
+int call_netdevice_notifiers(unsigned long val, struct net_device *dev)
+{
+	struct netdev_notifier_info info;
+
+	return call_netdevice_notifiers_info(val, dev, &info);
+}
+EXPORT_SYMBOL(call_netdevice_notifiers);
+
+#ifdef CONFIG_NET_CLS_ACT
+static struct static_key ingress_needed __read_mostly;
+
+void net_inc_ingress_queue(void)
+{
+	static_key_slow_inc(&ingress_needed);
+}
+EXPORT_SYMBOL_GPL(net_inc_ingress_queue);
+
+void net_dec_ingress_queue(void)
+{
+	static_key_slow_dec(&ingress_needed);
+}
+EXPORT_SYMBOL_GPL(net_dec_ingress_queue);
+#endif
+
+static struct static_key netstamp_needed __read_mostly;
+#ifdef HAVE_JUMP_LABEL
+/* We are not allowed to call static_key_slow_dec() from irq context
+ * If net_disable_timestamp() is called from irq context, defer the
+ * static_key_slow_dec() calls.
+ */
+static atomic_t netstamp_needed_deferred;
+#endif
+
+void net_enable_timestamp(void)
+{
+#ifdef HAVE_JUMP_LABEL
+	int deferred = atomic_xchg(&netstamp_needed_deferred, 0);
+
+	if (deferred) {
+		while (--deferred)
+			static_key_slow_dec(&netstamp_needed);
+		return;
+	}
+#endif
+	static_key_slow_inc(&netstamp_needed);
+}
+EXPORT_SYMBOL(net_enable_timestamp);
+
+void net_disable_timestamp(void)
+{
+#ifdef HAVE_JUMP_LABEL
+	if (in_interrupt()) {
+		atomic_inc(&netstamp_needed_deferred);
+		return;
+	}
+#endif
+	static_key_slow_dec(&netstamp_needed);
+}
+EXPORT_SYMBOL(net_disable_timestamp);
+
+static inline void net_timestamp_set(struct sk_buff *skb)
+{
+	skb->tstamp.tv64 = 0;
+	if (static_key_false(&netstamp_needed))
+		__net_timestamp(skb);
+}
+
+#define net_timestamp_check(COND, SKB)			\
+	if (static_key_false(&netstamp_needed)) {		\
+		if ((COND) && !(SKB)->tstamp.tv64)	\
+			__net_timestamp(SKB);		\
+	}						\
+
+bool is_skb_forwardable(struct net_device *dev, struct sk_buff *skb)
+{
+	unsigned int len;
+
+	if (!(dev->flags & IFF_UP))
+		return false;
+
+	len = dev->mtu + dev->hard_header_len + VLAN_HLEN;
+	if (skb->len <= len)
+		return true;
+
+	/* if TSO is enabled, we don't care about the length as the packet
+	 * could be forwarded without being segmented before
+	 */
+	if (skb_is_gso(skb))
+		return true;
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(is_skb_forwardable);
+
+int __dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
+{
+	if (skb_orphan_frags(skb, GFP_ATOMIC) ||
+	    unlikely(!is_skb_forwardable(dev, skb))) {
+		atomic_long_inc(&dev->rx_dropped);
+		kfree_skb(skb);
+		return NET_RX_DROP;
+	}
+
+	skb_scrub_packet(skb, true);
+	skb->priority = 0;
+	skb->protocol = eth_type_trans(skb, dev);
+	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__dev_forward_skb);
+
+/**
+ * dev_forward_skb - loopback an skb to another netif
+ *
+ * @dev: destination network device
+ * @skb: buffer to forward
+ *
+ * return values:
+ *	NET_RX_SUCCESS	(no congestion)
+ *	NET_RX_DROP     (packet was dropped, but freed)
+ *
+ * dev_forward_skb can be used for injecting an skb from the
+ * start_xmit function of one device into the receive queue
+ * of another device.
+ *
+ * The receiving device may be in another namespace, so
+ * we have to clear all information in the skb that could
+ * impact namespace isolation.
+ */
+int dev_forward_skb(struct net_device *dev, struct sk_buff *skb)
+{
+	return __dev_forward_skb(dev, skb) ?: netif_rx_internal(skb);
+}
+EXPORT_SYMBOL_GPL(dev_forward_skb);
+
+static inline int deliver_skb(struct sk_buff *skb,
+			      struct packet_type *pt_prev,
+			      struct net_device *orig_dev)
+{
+	if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
+		return -ENOMEM;
+	atomic_inc(&skb->users);
+	return pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
+}
+
+static inline void deliver_ptype_list_skb(struct sk_buff *skb,
+					  struct packet_type **pt,
+					  struct net_device *orig_dev,
+					  __be16 type,
+					  struct list_head *ptype_list)
+{
+	struct packet_type *ptype, *pt_prev = *pt;
+
+	list_for_each_entry_rcu(ptype, ptype_list, list) {
+		if (ptype->type != type)
+			continue;
+		if (pt_prev)
+			deliver_skb(skb, pt_prev, orig_dev);
+		pt_prev = ptype;
+	}
+	*pt = pt_prev;
+}
+
+static inline bool skb_loop_sk(struct packet_type *ptype, struct sk_buff *skb)
+{
+	if (!ptype->af_packet_priv || !skb->sk)
+		return false;
+
+	if (ptype->id_match)
+		return ptype->id_match(ptype, skb->sk);
+	else if ((struct sock *)ptype->af_packet_priv == skb->sk)
+		return true;
+
+	return false;
+}
+
+/*
+ *	Support routine. Sends outgoing frames to any network
+ *	taps currently in use.
+ */
+
+static void dev_queue_xmit_nit(struct sk_buff *skb, struct net_device *dev)
+{
+	struct packet_type *ptype;
+	struct sk_buff *skb2 = NULL;
+	struct packet_type *pt_prev = NULL;
+	struct list_head *ptype_list = &ptype_all;
+
+	rcu_read_lock();
+again:
+	list_for_each_entry_rcu(ptype, ptype_list, list) {
+		/* Never send packets back to the socket
+		 * they originated from - MvS (miquels@drinkel.ow.org)
+		 */
+		if (skb_loop_sk(ptype, skb))
+			continue;
+
+		if (pt_prev) {
+			deliver_skb(skb2, pt_prev, skb->dev);
+			pt_prev = ptype;
+			continue;
+		}
+
+		/* need to clone skb, done only once */
+		skb2 = skb_clone(skb, GFP_ATOMIC);
+		if (!skb2)
+			goto out_unlock;
+
+		net_timestamp_set(skb2);
+
+		/* skb->nh should be correctly
+		 * set by sender, so that the second statement is
+		 * just protection against buggy protocols.
+		 */
+		skb_reset_mac_header(skb2);
+
+		if (skb_network_header(skb2) < skb2->data ||
+		    skb_network_header(skb2) > skb_tail_pointer(skb2)) {
+			net_crit_ratelimited("protocol %04x is buggy, dev %s\n",
+					     ntohs(skb2->protocol),
+					     dev->name);
+			skb_reset_network_header(skb2);
+		}
+
+		skb2->transport_header = skb2->network_header;
+		skb2->pkt_type = PACKET_OUTGOING;
+		pt_prev = ptype;
+	}
+
+	if (ptype_list == &ptype_all) {
+		ptype_list = &dev->ptype_all;
+		goto again;
+	}
+out_unlock:
+	if (pt_prev)
+		pt_prev->func(skb2, skb->dev, pt_prev, skb->dev);
+	rcu_read_unlock();
+}
+
+/**
+ * netif_setup_tc - Handle tc mappings on real_num_tx_queues change
+ * @dev: Network device
+ * @txq: number of queues available
+ *
+ * If real_num_tx_queues is changed the tc mappings may no longer be
+ * valid. To resolve this verify the tc mapping remains valid and if
+ * not NULL the mapping. With no priorities mapping to this
+ * offset/count pair it will no longer be used. In the worst case TC0
+ * is invalid nothing can be done so disable priority mappings. If is
+ * expected that drivers will fix this mapping if they can before
+ * calling netif_set_real_num_tx_queues.
+ */
+static void netif_setup_tc(struct net_device *dev, unsigned int txq)
+{
+	int i;
+	struct netdev_tc_txq *tc = &dev->tc_to_txq[0];
+
+	/* If TC0 is invalidated disable TC mapping */
+	if (tc->offset + tc->count > txq) {
+		pr_warn("Number of in use tx queues changed invalidating tc mappings. Priority traffic classification disabled!\n");
+		dev->num_tc = 0;
+		return;
+	}
+
+	/* Invalidated prio to tc mappings set to TC0 */
+	for (i = 1; i < TC_BITMASK + 1; i++) {
+		int q = netdev_get_prio_tc_map(dev, i);
+
+		tc = &dev->tc_to_txq[q];
+		if (tc->offset + tc->count > txq) {
+			pr_warn("Number of in use tx queues changed. Priority %i to tc mapping %i is no longer valid. Setting map to 0\n",
+				i, q);
+			netdev_set_prio_tc_map(dev, i, 0);
+		}
+	}
+}
+
+#ifdef CONFIG_XPS
+static DEFINE_MUTEX(xps_map_mutex);
+#define xmap_dereference(P)		\
+	rcu_dereference_protected((P), lockdep_is_held(&xps_map_mutex))
+
+static struct xps_map *remove_xps_queue(struct xps_dev_maps *dev_maps,
+					int cpu, u16 index)
+{
+	struct xps_map *map = NULL;
+	int pos;
+
+	if (dev_maps)
+		map = xmap_dereference(dev_maps->cpu_map[cpu]);
+
+	for (pos = 0; map && pos < map->len; pos++) {
+		if (map->queues[pos] == index) {
+			if (map->len > 1) {
+				map->queues[pos] = map->queues[--map->len];
+			} else {
+				RCU_INIT_POINTER(dev_maps->cpu_map[cpu], NULL);
+				kfree_rcu(map, rcu);
+				map = NULL;
+			}
+			break;
+		}
+	}
+
+	return map;
+}
+
+static void netif_reset_xps_queues_gt(struct net_device *dev, u16 index)
+{
+	struct xps_dev_maps *dev_maps;
+	int cpu, i;
+	bool active = false;
+
+	mutex_lock(&xps_map_mutex);
+	dev_maps = xmap_dereference(dev->xps_maps);
+
+	if (!dev_maps)
+		goto out_no_maps;
+
+	for_each_possible_cpu(cpu) {
+		for (i = index; i < dev->num_tx_queues; i++) {
+			if (!remove_xps_queue(dev_maps, cpu, i))
+				break;
+		}
+		if (i == dev->num_tx_queues)
+			active = true;
+	}
+
+	if (!active) {
+		RCU_INIT_POINTER(dev->xps_maps, NULL);
+		kfree_rcu(dev_maps, rcu);
+	}
+
+	for (i = index; i < dev->num_tx_queues; i++)
+		netdev_queue_numa_node_write(netdev_get_tx_queue(dev, i),
+					     NUMA_NO_NODE);
+
+out_no_maps:
+	mutex_unlock(&xps_map_mutex);
+}
+
+static struct xps_map *expand_xps_map(struct xps_map *map,
+				      int cpu, u16 index)
+{
+	struct xps_map *new_map;
+	int alloc_len = XPS_MIN_MAP_ALLOC;
+	int i, pos;
+
+	for (pos = 0; map && pos < map->len; pos++) {
+		if (map->queues[pos] != index)
+			continue;
+		return map;
+	}
+
+	/* Need to add queue to this CPU's existing map */
+	if (map) {
+		if (pos < map->alloc_len)
+			return map;
+
+		alloc_len = map->alloc_len * 2;
+	}
+
+	/* Need to allocate new map to store queue on this CPU's map */
+	new_map = kzalloc_node(XPS_MAP_SIZE(alloc_len), GFP_KERNEL,
+			       cpu_to_node(cpu));
+	if (!new_map)
+		return NULL;
+
+	for (i = 0; i < pos; i++)
+		new_map->queues[i] = map->queues[i];
+	new_map->alloc_len = alloc_len;
+	new_map->len = pos;
+
+	return new_map;
+}
+
+int netif_set_xps_queue(struct net_device *dev, const struct cpumask *mask,
+			u16 index)
+{
+	struct xps_dev_maps *dev_maps, *new_dev_maps = NULL;
+	struct xps_map *map, *new_map;
+	int maps_sz = max_t(unsigned int, XPS_DEV_MAPS_SIZE, L1_CACHE_BYTES);
+	int cpu, numa_node_id = -2;
+	bool active = false;
+
+	mutex_lock(&xps_map_mutex);
+
+	dev_maps = xmap_dereference(dev->xps_maps);
+
+	/* allocate memory for queue storage */
+	for_each_online_cpu(cpu) {
+		if (!cpumask_test_cpu(cpu, mask))
+			continue;
+
+		if (!new_dev_maps)
+			new_dev_maps = kzalloc(maps_sz, GFP_KERNEL);
+		if (!new_dev_maps) {
+			mutex_unlock(&xps_map_mutex);
+			return -ENOMEM;
+		}
+
+		map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
+				 NULL;
+
+		map = expand_xps_map(map, cpu, index);
+		if (!map)
+			goto error;
+
+		RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
+	}
+
+	if (!new_dev_maps)
+		goto out_no_new_maps;
+
+	for_each_possible_cpu(cpu) {
+		if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu)) {
+			/* add queue to CPU maps */
+			int pos = 0;
+
+			map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
+			while ((pos < map->len) && (map->queues[pos] != index))
+				pos++;
+
+			if (pos == map->len)
+				map->queues[map->len++] = index;
+#ifdef CONFIG_NUMA
+			if (numa_node_id == -2)
+				numa_node_id = cpu_to_node(cpu);
+			else if (numa_node_id != cpu_to_node(cpu))
+				numa_node_id = -1;
+#endif
+		} else if (dev_maps) {
+			/* fill in the new device map from the old device map */
+			map = xmap_dereference(dev_maps->cpu_map[cpu]);
+			RCU_INIT_POINTER(new_dev_maps->cpu_map[cpu], map);
+		}
+
+	}
+
+	rcu_assign_pointer(dev->xps_maps, new_dev_maps);
+
+	/* Cleanup old maps */
+	if (dev_maps) {
+		for_each_possible_cpu(cpu) {
+			new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
+			map = xmap_dereference(dev_maps->cpu_map[cpu]);
+			if (map && map != new_map)
+				kfree_rcu(map, rcu);
+		}
+
+		kfree_rcu(dev_maps, rcu);
+	}
+
+	dev_maps = new_dev_maps;
+	active = true;
+
+out_no_new_maps:
+	/* update Tx queue numa node */
+	netdev_queue_numa_node_write(netdev_get_tx_queue(dev, index),
+				     (numa_node_id >= 0) ? numa_node_id :
+				     NUMA_NO_NODE);
+
+	if (!dev_maps)
+		goto out_no_maps;
+
+	/* removes queue from unused CPUs */
+	for_each_possible_cpu(cpu) {
+		if (cpumask_test_cpu(cpu, mask) && cpu_online(cpu))
+			continue;
+
+		if (remove_xps_queue(dev_maps, cpu, index))
+			active = true;
+	}
+
+	/* free map if not active */
+	if (!active) {
+		RCU_INIT_POINTER(dev->xps_maps, NULL);
+		kfree_rcu(dev_maps, rcu);
+	}
+
+out_no_maps:
+	mutex_unlock(&xps_map_mutex);
+
+	return 0;
+error:
+	/* remove any maps that we added */
+	for_each_possible_cpu(cpu) {
+		new_map = xmap_dereference(new_dev_maps->cpu_map[cpu]);
+		map = dev_maps ? xmap_dereference(dev_maps->cpu_map[cpu]) :
+				 NULL;
+		if (new_map && new_map != map)
+			kfree(new_map);
+	}
+
+	mutex_unlock(&xps_map_mutex);
+
+	kfree(new_dev_maps);
+	return -ENOMEM;
+}
+EXPORT_SYMBOL(netif_set_xps_queue);
+
+#endif
+/*
+ * Routine to help set real_num_tx_queues. To avoid skbs mapped to queues
+ * greater then real_num_tx_queues stale skbs on the qdisc must be flushed.
+ */
+int netif_set_real_num_tx_queues(struct net_device *dev, unsigned int txq)
+{
+	int rc;
+
+	if (txq < 1 || txq > dev->num_tx_queues)
+		return -EINVAL;
+
+	if (dev->reg_state == NETREG_REGISTERED ||
+	    dev->reg_state == NETREG_UNREGISTERING) {
+		ASSERT_RTNL();
+
+		rc = netdev_queue_update_kobjects(dev, dev->real_num_tx_queues,
+						  txq);
+		if (rc)
+			return rc;
+
+		if (dev->num_tc)
+			netif_setup_tc(dev, txq);
+
+		if (txq < dev->real_num_tx_queues) {
+			qdisc_reset_all_tx_gt(dev, txq);
+#ifdef CONFIG_XPS
+			netif_reset_xps_queues_gt(dev, txq);
+#endif
+		}
+	}
+
+	dev->real_num_tx_queues = txq;
+	return 0;
+}
+EXPORT_SYMBOL(netif_set_real_num_tx_queues);
+
+#ifdef CONFIG_SYSFS
+/**
+ *	netif_set_real_num_rx_queues - set actual number of RX queues used
+ *	@dev: Network device
+ *	@rxq: Actual number of RX queues
+ *
+ *	This must be called either with the rtnl_lock held or before
+ *	registration of the net device.  Returns 0 on success, or a
+ *	negative error code.  If called before registration, it always
+ *	succeeds.
+ */
+int netif_set_real_num_rx_queues(struct net_device *dev, unsigned int rxq)
+{
+	int rc;
+
+	if (rxq < 1 || rxq > dev->num_rx_queues)
+		return -EINVAL;
+
+	if (dev->reg_state == NETREG_REGISTERED) {
+		ASSERT_RTNL();
+
+		rc = net_rx_queue_update_kobjects(dev, dev->real_num_rx_queues,
+						  rxq);
+		if (rc)
+			return rc;
+	}
+
+	dev->real_num_rx_queues = rxq;
+	return 0;
+}
+EXPORT_SYMBOL(netif_set_real_num_rx_queues);
+#endif
+
+/**
+ * netif_get_num_default_rss_queues - default number of RSS queues
+ *
+ * This routine should set an upper limit on the number of RSS queues
+ * used by default by multiqueue devices.
+ */
+int netif_get_num_default_rss_queues(void)
+{
+	return min_t(int, DEFAULT_MAX_NUM_RSS_QUEUES, num_online_cpus());
+}
+EXPORT_SYMBOL(netif_get_num_default_rss_queues);
+
+static inline void __netif_reschedule(struct Qdisc *q)
+{
+	struct softnet_data *sd;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	sd = this_cpu_ptr(&softnet_data);
+	q->next_sched = NULL;
+	*sd->output_queue_tailp = q;
+	sd->output_queue_tailp = &q->next_sched;
+	raise_softirq_irqoff(NET_TX_SOFTIRQ);
+	local_irq_restore(flags);
+}
+
+void __netif_schedule(struct Qdisc *q)
+{
+	if (!test_and_set_bit(__QDISC_STATE_SCHED, &q->state))
+		__netif_reschedule(q);
+}
+EXPORT_SYMBOL(__netif_schedule);
+
+struct dev_kfree_skb_cb {
+	enum skb_free_reason reason;
+};
+
+static struct dev_kfree_skb_cb *get_kfree_skb_cb(const struct sk_buff *skb)
+{
+	return (struct dev_kfree_skb_cb *)skb->cb;
+}
+
+void netif_schedule_queue(struct netdev_queue *txq)
+{
+	rcu_read_lock();
+	if (!(txq->state & QUEUE_STATE_ANY_XOFF)) {
+		struct Qdisc *q = rcu_dereference(txq->qdisc);
+
+		__netif_schedule(q);
+	}
+	rcu_read_unlock();
+}
+EXPORT_SYMBOL(netif_schedule_queue);
+
+/**
+ *	netif_wake_subqueue - allow sending packets on subqueue
+ *	@dev: network device
+ *	@queue_index: sub queue index
+ *
+ * Resume individual transmit queue of a device with multiple transmit queues.
+ */
+void netif_wake_subqueue(struct net_device *dev, u16 queue_index)
+{
+	struct netdev_queue *txq = netdev_get_tx_queue(dev, queue_index);
+
+	if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &txq->state)) {
+		struct Qdisc *q;
+
+		rcu_read_lock();
+		q = rcu_dereference(txq->qdisc);
+		__netif_schedule(q);
+		rcu_read_unlock();
+	}
+}
+EXPORT_SYMBOL(netif_wake_subqueue);
+
+void netif_tx_wake_queue(struct netdev_queue *dev_queue)
+{
+	if (test_and_clear_bit(__QUEUE_STATE_DRV_XOFF, &dev_queue->state)) {
+		struct Qdisc *q;
+
+		rcu_read_lock();
+		q = rcu_dereference(dev_queue->qdisc);
+		__netif_schedule(q);
+		rcu_read_unlock();
+	}
+}
+EXPORT_SYMBOL(netif_tx_wake_queue);
+
+void __dev_kfree_skb_irq(struct sk_buff *skb, enum skb_free_reason reason)
+{
+	unsigned long flags;
+
+	if (likely(atomic_read(&skb->users) == 1)) {
+		smp_rmb();
+		atomic_set(&skb->users, 0);
+	} else if (likely(!atomic_dec_and_test(&skb->users))) {
+		return;
+	}
+	get_kfree_skb_cb(skb)->reason = reason;
+	local_irq_save(flags);
+	skb->next = __this_cpu_read(softnet_data.completion_queue);
+	__this_cpu_write(softnet_data.completion_queue, skb);
+	raise_softirq_irqoff(NET_TX_SOFTIRQ);
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL(__dev_kfree_skb_irq);
+
+void __dev_kfree_skb_any(struct sk_buff *skb, enum skb_free_reason reason)
+{
+	if (in_irq() || irqs_disabled())
+		__dev_kfree_skb_irq(skb, reason);
+	else
+		dev_kfree_skb(skb);
+}
+EXPORT_SYMBOL(__dev_kfree_skb_any);
+
+
+/**
+ * netif_device_detach - mark device as removed
+ * @dev: network device
+ *
+ * Mark device as removed from system and therefore no longer available.
+ */
+void netif_device_detach(struct net_device *dev)
+{
+	if (test_and_clear_bit(__LINK_STATE_PRESENT, &dev->state) &&
+	    netif_running(dev)) {
+		netif_tx_stop_all_queues(dev);
+	}
+}
+EXPORT_SYMBOL(netif_device_detach);
+
+/**
+ * netif_device_attach - mark device as attached
+ * @dev: network device
+ *
+ * Mark device as attached from system and restart if needed.
+ */
+void netif_device_attach(struct net_device *dev)
+{
+	if (!test_and_set_bit(__LINK_STATE_PRESENT, &dev->state) &&
+	    netif_running(dev)) {
+		netif_tx_wake_all_queues(dev);
+		__netdev_watchdog_up(dev);
+	}
+}
+EXPORT_SYMBOL(netif_device_attach);
+
+static void skb_warn_bad_offload(const struct sk_buff *skb)
+{
+	static const netdev_features_t null_features = 0;
+	struct net_device *dev = skb->dev;
+	const char *driver = "";
+
+	if (!net_ratelimit())
+		return;
+
+	if (dev && dev->dev.parent)
+		driver = dev_driver_string(dev->dev.parent);
+
+	WARN(1, "%s: caps=(%pNF, %pNF) len=%d data_len=%d gso_size=%d "
+	     "gso_type=%d ip_summed=%d\n",
+	     driver, dev ? &dev->features : &null_features,
+	     skb->sk ? &skb->sk->sk_route_caps : &null_features,
+	     skb->len, skb->data_len, skb_shinfo(skb)->gso_size,
+	     skb_shinfo(skb)->gso_type, skb->ip_summed);
+}
+
+/*
+ * Invalidate hardware checksum when packet is to be mangled, and
+ * complete checksum manually on outgoing path.
+ */
+int skb_checksum_help(struct sk_buff *skb)
+{
+	__wsum csum;
+	int ret = 0, offset;
+
+	if (skb->ip_summed == CHECKSUM_COMPLETE)
+		goto out_set_summed;
+
+	if (unlikely(skb_shinfo(skb)->gso_size)) {
+		skb_warn_bad_offload(skb);
+		return -EINVAL;
+	}
+
+	/* Before computing a checksum, we should make sure no frag could
+	 * be modified by an external entity : checksum could be wrong.
+	 */
+	if (skb_has_shared_frag(skb)) {
+		ret = __skb_linearize(skb);
+		if (ret)
+			goto out;
+	}
+
+	offset = skb_checksum_start_offset(skb);
+	BUG_ON(offset >= skb_headlen(skb));
+	csum = skb_checksum(skb, offset, skb->len - offset, 0);
+
+	offset += skb->csum_offset;
+	BUG_ON(offset + sizeof(__sum16) > skb_headlen(skb));
+
+	if (skb_cloned(skb) &&
+	    !skb_clone_writable(skb, offset + sizeof(__sum16))) {
+		ret = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
+		if (ret)
+			goto out;
+	}
+
+	*(__sum16 *)(skb->data + offset) = csum_fold(csum);
+out_set_summed:
+	skb->ip_summed = CHECKSUM_NONE;
+out:
+	return ret;
+}
+EXPORT_SYMBOL(skb_checksum_help);
+
+__be16 skb_network_protocol(struct sk_buff *skb, int *depth)
+{
+	__be16 type = skb->protocol;
+
+	/* Tunnel gso handlers can set protocol to ethernet. */
+	if (type == htons(ETH_P_TEB)) {
+		struct ethhdr *eth;
+
+		if (unlikely(!pskb_may_pull(skb, sizeof(struct ethhdr))))
+			return 0;
+
+		eth = (struct ethhdr *)skb_mac_header(skb);
+		type = eth->h_proto;
+	}
+
+	return __vlan_get_protocol(skb, type, depth);
+}
+
+/**
+ *	skb_mac_gso_segment - mac layer segmentation handler.
+ *	@skb: buffer to segment
+ *	@features: features for the output path (see dev->features)
+ */
+struct sk_buff *skb_mac_gso_segment(struct sk_buff *skb,
+				    netdev_features_t features)
+{
+	struct sk_buff *segs = ERR_PTR(-EPROTONOSUPPORT);
+	struct packet_offload *ptype;
+	int vlan_depth = skb->mac_len;
+	__be16 type = skb_network_protocol(skb, &vlan_depth);
+
+	if (unlikely(!type))
+		return ERR_PTR(-EINVAL);
+
+	__skb_pull(skb, vlan_depth);
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(ptype, &offload_base, list) {
+		if (ptype->type == type && ptype->callbacks.gso_segment) {
+			segs = ptype->callbacks.gso_segment(skb, features);
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	__skb_push(skb, skb->data - skb_mac_header(skb));
+
+	return segs;
+}
+EXPORT_SYMBOL(skb_mac_gso_segment);
+
+
+/* openvswitch calls this on rx path, so we need a different check.
+ */
+static inline bool skb_needs_check(struct sk_buff *skb, bool tx_path)
+{
+	if (tx_path)
+		return skb->ip_summed != CHECKSUM_PARTIAL;
+	else
+		return skb->ip_summed == CHECKSUM_NONE;
+}
+
+/**
+ *	__skb_gso_segment - Perform segmentation on skb.
+ *	@skb: buffer to segment
+ *	@features: features for the output path (see dev->features)
+ *	@tx_path: whether it is called in TX path
+ *
+ *	This function segments the given skb and returns a list of segments.
+ *
+ *	It may return NULL if the skb requires no segmentation.  This is
+ *	only possible when GSO is used for verifying header integrity.
+ */
+struct sk_buff *__skb_gso_segment(struct sk_buff *skb,
+				  netdev_features_t features, bool tx_path)
+{
+	if (unlikely(skb_needs_check(skb, tx_path))) {
+		int err;
+
+		skb_warn_bad_offload(skb);
+
+		err = skb_cow_head(skb, 0);
+		if (err < 0)
+			return ERR_PTR(err);
+	}
+
+	SKB_GSO_CB(skb)->mac_offset = skb_headroom(skb);
+	SKB_GSO_CB(skb)->encap_level = 0;
+
+	skb_reset_mac_header(skb);
+	skb_reset_mac_len(skb);
+
+	return skb_mac_gso_segment(skb, features);
+}
+EXPORT_SYMBOL(__skb_gso_segment);
+
+/* Take action when hardware reception checksum errors are detected. */
+#ifdef CONFIG_BUG
+void netdev_rx_csum_fault(struct net_device *dev)
+{
+	if (net_ratelimit()) {
+		pr_err("%s: hw csum failure\n", dev ? dev->name : "<unknown>");
+		dump_stack();
+	}
+}
+EXPORT_SYMBOL(netdev_rx_csum_fault);
+#endif
+
+/* Actually, we should eliminate this check as soon as we know, that:
+ * 1. IOMMU is present and allows to map all the memory.
+ * 2. No high memory really exists on this machine.
+ */
+
+static int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
+{
+#ifdef CONFIG_HIGHMEM
+	int i;
+	if (!(dev->features & NETIF_F_HIGHDMA)) {
+		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+			if (PageHighMem(skb_frag_page(frag)))
+				return 1;
+		}
+	}
+
+	if (PCI_DMA_BUS_IS_PHYS) {
+		struct device *pdev = dev->dev.parent;
+
+		if (!pdev)
+			return 0;
+		for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
+			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
+			dma_addr_t addr = page_to_phys(skb_frag_page(frag));
+			if (!pdev->dma_mask || addr + PAGE_SIZE - 1 > *pdev->dma_mask)
+				return 1;
+		}
+	}
+#endif
+	return 0;
+}
+
+/* If MPLS offload request, verify we are testing hardware MPLS features
+ * instead of standard features for the netdev.
+ */
+#if IS_ENABLED(CONFIG_NET_MPLS_GSO)
+static netdev_features_t net_mpls_features(struct sk_buff *skb,
+					   netdev_features_t features,
+					   __be16 type)
+{
+	if (eth_p_mpls(type))
+		features &= skb->dev->mpls_features;
+
+	return features;
+}
+#else
+static netdev_features_t net_mpls_features(struct sk_buff *skb,
+					   netdev_features_t features,
+					   __be16 type)
+{
+	return features;
+}
+#endif
+
+static netdev_features_t harmonize_features(struct sk_buff *skb,
+	netdev_features_t features)
+{
+	int tmp;
+	__be16 type;
+
+	type = skb_network_protocol(skb, &tmp);
+	features = net_mpls_features(skb, features, type);
+
+	if (skb->ip_summed != CHECKSUM_NONE &&
+	    !can_checksum_protocol(features, type)) {
+		features &= ~NETIF_F_ALL_CSUM;
+	} else if (illegal_highdma(skb->dev, skb)) {
+		features &= ~NETIF_F_SG;
+	}
+
+	return features;
+}
+
+netdev_features_t passthru_features_check(struct sk_buff *skb,
+					  struct net_device *dev,
+					  netdev_features_t features)
+{
+	return features;
+}
+EXPORT_SYMBOL(passthru_features_check);
+
+static netdev_features_t dflt_features_check(const struct sk_buff *skb,
+					     struct net_device *dev,
+					     netdev_features_t features)
+{
+	return vlan_features_check(skb, features);
+}
+
+netdev_features_t netif_skb_features(struct sk_buff *skb)
+{
+	struct net_device *dev = skb->dev;
+	netdev_features_t features = dev->features;
+	u16 gso_segs = skb_shinfo(skb)->gso_segs;
+
+	if (gso_segs > dev->gso_max_segs || gso_segs < dev->gso_min_segs)
+		features &= ~NETIF_F_GSO_MASK;
+
+	/* If encapsulation offload request, verify we are testing
+	 * hardware encapsulation features instead of standard
+	 * features for the netdev
+	 */
+	if (skb->encapsulation)
+		features &= dev->hw_enc_features;
+
+	if (skb_vlan_tagged(skb))
+		features = netdev_intersect_features(features,
+						     dev->vlan_features |
+						     NETIF_F_HW_VLAN_CTAG_TX |
+						     NETIF_F_HW_VLAN_STAG_TX);
+
+	if (dev->netdev_ops->ndo_features_check)
+		features &= dev->netdev_ops->ndo_features_check(skb, dev,
+								features);
+	else
+		features &= dflt_features_check(skb, dev, features);
+
+	return harmonize_features(skb, features);
+}
+EXPORT_SYMBOL(netif_skb_features);
+
+static int xmit_one(struct sk_buff *skb, struct net_device *dev,
+		    struct netdev_queue *txq, bool more)
+{
+	unsigned int len;
+	int rc;
+
+	if (!list_empty(&ptype_all) || !list_empty(&dev->ptype_all))
+		dev_queue_xmit_nit(skb, dev);
+
+	len = skb->len;
+	trace_net_dev_start_xmit(skb, dev);
+	rc = netdev_start_xmit(skb, dev, txq, more);
+	trace_net_dev_xmit(skb, rc, dev, len);
+
+	return rc;
+}
+
+struct sk_buff *dev_hard_start_xmit(struct sk_buff *first, struct net_device *dev,
+				    struct netdev_queue *txq, int *ret)
+{
+	struct sk_buff *skb = first;
+	int rc = NETDEV_TX_OK;
+
+	while (skb) {
+		struct sk_buff *next = skb->next;
+
+		skb->next = NULL;
+		rc = xmit_one(skb, dev, txq, next != NULL);
+		if (unlikely(!dev_xmit_complete(rc))) {
+			skb->next = next;
+			goto out;
+		}
+
+		skb = next;
+		if (netif_xmit_stopped(txq) && skb) {
+			rc = NETDEV_TX_BUSY;
+			break;
+		}
+	}
+
+out:
+	*ret = rc;
+	return skb;
+}
+
+static struct sk_buff *validate_xmit_vlan(struct sk_buff *skb,
+					  netdev_features_t features)
+{
+	if (skb_vlan_tag_present(skb) &&
+	    !vlan_hw_offload_capable(features, skb->vlan_proto))
+		skb = __vlan_hwaccel_push_inside(skb);
+	return skb;
+}
+
+static struct sk_buff *validate_xmit_skb(struct sk_buff *skb, struct net_device *dev)
+{
+	netdev_features_t features;
+
+	if (skb->next)
+		return skb;
+
+	features = netif_skb_features(skb);
+	skb = validate_xmit_vlan(skb, features);
+	if (unlikely(!skb))
+		goto out_null;
+
+	if (netif_needs_gso(skb, features)) {
+		struct sk_buff *segs;
+
+		segs = skb_gso_segment(skb, features);
+		if (IS_ERR(segs)) {
+			goto out_kfree_skb;
+		} else if (segs) {
+			consume_skb(skb);
+			skb = segs;
+		}
+	} else {
+		if (skb_needs_linearize(skb, features) &&
+		    __skb_linearize(skb))
+			goto out_kfree_skb;
+
+		/* If packet is not checksummed and device does not
+		 * support checksumming for this protocol, complete
+		 * checksumming here.
+		 */
+		if (skb->ip_summed == CHECKSUM_PARTIAL) {
+			if (skb->encapsulation)
+				skb_set_inner_transport_header(skb,
+							       skb_checksum_start_offset(skb));
+			else
+				skb_set_transport_header(skb,
+							 skb_checksum_start_offset(skb));
+			if (!(features & NETIF_F_ALL_CSUM) &&
+			    skb_checksum_help(skb))
+				goto out_kfree_skb;
+		}
+	}
+
+	return skb;
+
+out_kfree_skb:
+	kfree_skb(skb);
+out_null:
+	return NULL;
+}
+
+struct sk_buff *validate_xmit_skb_list(struct sk_buff *skb, struct net_device *dev)
+{
+	struct sk_buff *next, *head = NULL, *tail;
+
+	for (; skb != NULL; skb = next) {
+		next = skb->next;
+		skb->next = NULL;
+
+		/* in case skb wont be segmented, point to itself */
+		skb->prev = skb;
+
+		skb = validate_xmit_skb(skb, dev);
+		if (!skb)
+			continue;
+
+		if (!head)
+			head = skb;
+		else
+			tail->next = skb;
+		/* If skb was segmented, skb->prev points to
+		 * the last segment. If not, it still contains skb.
+		 */
+		tail = skb->prev;
+	}
+	return head;
+}
+
+static void qdisc_pkt_len_init(struct sk_buff *skb)
+{
+	const struct skb_shared_info *shinfo = skb_shinfo(skb);
+
+	qdisc_skb_cb(skb)->pkt_len = skb->len;
+
+	/* To get more precise estimation of bytes sent on wire,
+	 * we add to pkt_len the headers size of all segments
+	 */
+	if (shinfo->gso_size)  {
+		unsigned int hdr_len;
+		u16 gso_segs = shinfo->gso_segs;
+
+		/* mac layer + network layer */
+		hdr_len = skb_transport_header(skb) - skb_mac_header(skb);
+
+		/* + transport layer */
+		if (likely(shinfo->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)))
+			hdr_len += tcp_hdrlen(skb);
+		else
+			hdr_len += sizeof(struct udphdr);
+
+		if (shinfo->gso_type & SKB_GSO_DODGY)
+			gso_segs = DIV_ROUND_UP(skb->len - hdr_len,
+						shinfo->gso_size);
+
+		qdisc_skb_cb(skb)->pkt_len += (gso_segs - 1) * hdr_len;
+	}
+}
+
+static inline int __dev_xmit_skb(struct sk_buff *skb, struct Qdisc *q,
+				 struct net_device *dev,
+				 struct netdev_queue *txq)
+{
+	spinlock_t *root_lock = qdisc_lock(q);
+	bool contended;
+	int rc;
+
+	qdisc_pkt_len_init(skb);
+	qdisc_calculate_pkt_len(skb, q);
+	/*
+	 * Heuristic to force contended enqueues to serialize on a
+	 * separate lock before trying to get qdisc main lock.
+	 * This permits __QDISC___STATE_RUNNING owner to get the lock more
+	 * often and dequeue packets faster.
+	 */
+	contended = qdisc_is_running(q);
+	if (unlikely(contended))
+		spin_lock(&q->busylock);
+
+	spin_lock(root_lock);
+	if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
+		kfree_skb(skb);
+		rc = NET_XMIT_DROP;
+	} else if ((q->flags & TCQ_F_CAN_BYPASS) && !qdisc_qlen(q) &&
+		   qdisc_run_begin(q)) {
+		/*
+		 * This is a work-conserving queue; there are no old skbs
+		 * waiting to be sent out; and the qdisc is not running -
+		 * xmit the skb directly.
+		 */
+
+		qdisc_bstats_update(q, skb);
+
+		if (sch_direct_xmit(skb, q, dev, txq, root_lock, true)) {
+			if (unlikely(contended)) {
+				spin_unlock(&q->busylock);
+				contended = false;
+			}
+			__qdisc_run(q);
+		} else
+			qdisc_run_end(q);
+
+		rc = NET_XMIT_SUCCESS;
+	} else {
+		rc = q->enqueue(skb, q) & NET_XMIT_MASK;
+		if (qdisc_run_begin(q)) {
+			if (unlikely(contended)) {
+				spin_unlock(&q->busylock);
+				contended = false;
+			}
+			__qdisc_run(q);
+		}
+	}
+	spin_unlock(root_lock);
+	if (unlikely(contended))
+		spin_unlock(&q->busylock);
+	return rc;
+}
+
+#if IS_ENABLED(CONFIG_CGROUP_NET_PRIO)
+static void skb_update_prio(struct sk_buff *skb)
+{
+	struct netprio_map *map = rcu_dereference_bh(skb->dev->priomap);
+
+	if (!skb->priority && skb->sk && map) {
+		unsigned int prioidx = skb->sk->sk_cgrp_prioidx;
+
+		if (prioidx < map->priomap_len)
+			skb->priority = map->priomap[prioidx];
+	}
+}
+#else
+#define skb_update_prio(skb)
+#endif
+
+DEFINE_PER_CPU(int, xmit_recursion);
+EXPORT_SYMBOL(xmit_recursion);
+
+#define RECURSION_LIMIT 10
+
+/**
+ *	dev_loopback_xmit - loop back @skb
+ *	@skb: buffer to transmit
+ */
+int dev_loopback_xmit(struct sock *sk, struct sk_buff *skb)
+{
+	skb_reset_mac_header(skb);
+	__skb_pull(skb, skb_network_offset(skb));
+	skb->pkt_type = PACKET_LOOPBACK;
+	skb->ip_summed = CHECKSUM_UNNECESSARY;
+	WARN_ON(!skb_dst(skb));
+	skb_dst_force(skb);
+	netif_rx_ni(skb);
+	return 0;
+}
+EXPORT_SYMBOL(dev_loopback_xmit);
+
+/**
+ *	__dev_queue_xmit - transmit a buffer
+ *	@skb: buffer to transmit
+ *	@accel_priv: private data used for L2 forwarding offload
+ *
+ *	Queue a buffer for transmission to a network device. The caller must
+ *	have set the device and priority and built the buffer before calling
+ *	this function. The function can be called from an interrupt.
+ *
+ *	A negative errno code is returned on a failure. A success does not
+ *	guarantee the frame will be transmitted as it may be dropped due
+ *	to congestion or traffic shaping.
+ *
+ * -----------------------------------------------------------------------------------
+ *      I notice this method can also return errors from the queue disciplines,
+ *      including NET_XMIT_DROP, which is a positive value.  So, errors can also
+ *      be positive.
+ *
+ *      Regardless of the return value, the skb is consumed, so it is currently
+ *      difficult to retry a send to this method.  (You can bump the ref count
+ *      before sending to hold a reference for retry if you are careful.)
+ *
+ *      When calling this method, interrupts MUST be enabled.  This is because
+ *      the BH enable code must have IRQs enabled so that it will not deadlock.
+ *          --BLG
+ */
+static int __dev_queue_xmit(struct sk_buff *skb, void *accel_priv)
+{
+	struct net_device *dev = skb->dev;
+	struct netdev_queue *txq;
+	struct Qdisc *q;
+	int rc = -ENOMEM;
+
+	skb_reset_mac_header(skb);
+
+	if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_SCHED_TSTAMP))
+		__skb_tstamp_tx(skb, NULL, skb->sk, SCM_TSTAMP_SCHED);
+
+	/* Disable soft irqs for various locks below. Also
+	 * stops preemption for RCU.
+	 */
+	rcu_read_lock_bh();
+
+	skb_update_prio(skb);
+
+	/* If device/qdisc don't need skb->dst, release it right now while
+	 * its hot in this cpu cache.
+	 */
+	if (dev->priv_flags & IFF_XMIT_DST_RELEASE)
+		skb_dst_drop(skb);
+	else
+		skb_dst_force(skb);
+
+	txq = netdev_pick_tx(dev, skb, accel_priv);
+	q = rcu_dereference_bh(txq->qdisc);
+
+#ifdef CONFIG_NET_CLS_ACT
+	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_EGRESS);
+#endif
+	trace_net_dev_queue(skb);
+	if (q->enqueue) {
+		rc = __dev_xmit_skb(skb, q, dev, txq);
+		goto out;
+	}
+
+	/* The device has no queue. Common case for software devices:
+	   loopback, all the sorts of tunnels...
+
+	   Really, it is unlikely that netif_tx_lock protection is necessary
+	   here.  (f.e. loopback and IP tunnels are clean ignoring statistics
+	   counters.)
+	   However, it is possible, that they rely on protection
+	   made by us here.
+
+	   Check this and shot the lock. It is not prone from deadlocks.
+	   Either shot noqueue qdisc, it is even simpler 8)
+	 */
+	if (dev->flags & IFF_UP) {
+		int cpu = smp_processor_id(); /* ok because BHs are off */
+
+		if (txq->xmit_lock_owner != cpu) {
+
+			if (__this_cpu_read(xmit_recursion) > RECURSION_LIMIT)
+				goto recursion_alert;
+
+			skb = validate_xmit_skb(skb, dev);
+			if (!skb)
+				goto drop;
+
+			HARD_TX_LOCK(dev, txq, cpu);
+
+			if (!netif_xmit_stopped(txq)) {
+				__this_cpu_inc(xmit_recursion);
+				skb = dev_hard_start_xmit(skb, dev, txq, &rc);
+				__this_cpu_dec(xmit_recursion);
+				if (dev_xmit_complete(rc)) {
+					HARD_TX_UNLOCK(dev, txq);
+					goto out;
+				}
+			}
+			HARD_TX_UNLOCK(dev, txq);
+			net_crit_ratelimited("Virtual device %s asks to queue packet!\n",
+					     dev->name);
+		} else {
+			/* Recursion is detected! It is possible,
+			 * unfortunately
+			 */
+recursion_alert:
+			net_crit_ratelimited("Dead loop on virtual device %s, fix it urgently!\n",
+					     dev->name);
+		}
+	}
+
+	rc = -ENETDOWN;
+drop:
+	rcu_read_unlock_bh();
+
+	atomic_long_inc(&dev->tx_dropped);
+	kfree_skb_list(skb);
+	return rc;
+out:
+	rcu_read_unlock_bh();
+	return rc;
+}
+
+int dev_queue_xmit_sk(struct sock *sk, struct sk_buff *skb)
+{
+	return __dev_queue_xmit(skb, NULL);
+}
+EXPORT_SYMBOL(dev_queue_xmit_sk);
+
+int dev_queue_xmit_accel(struct sk_buff *skb, void *accel_priv)
+{
+	return __dev_queue_xmit(skb, accel_priv);
+}
+EXPORT_SYMBOL(dev_queue_xmit_accel);
+
+
+/*=======================================================================
+			Receiver routines
+  =======================================================================*/
+
+int netdev_max_backlog __read_mostly = 1000;
+EXPORT_SYMBOL(netdev_max_backlog);
+
+int netdev_tstamp_prequeue __read_mostly = 1;
+int netdev_budget __read_mostly = 300;
+int weight_p __read_mostly = 64;            /* old backlog weight */
+
+/* Called with irq disabled */
+static inline void ____napi_schedule(struct softnet_data *sd,
+				     struct napi_struct *napi)
+{
+	list_add_tail(&napi->poll_list, &sd->poll_list);
+	__raise_softirq_irqoff(NET_RX_SOFTIRQ);
+}
+
+#ifdef CONFIG_RPS
+
+/* One global table that all flow-based protocols share. */
+struct rps_sock_flow_table __rcu *rps_sock_flow_table __read_mostly;
+EXPORT_SYMBOL(rps_sock_flow_table);
+u32 rps_cpu_mask __read_mostly;
+EXPORT_SYMBOL(rps_cpu_mask);
+
+struct static_key rps_needed __read_mostly;
+
+static struct rps_dev_flow *
+set_rps_cpu(struct net_device *dev, struct sk_buff *skb,
+	    struct rps_dev_flow *rflow, u16 next_cpu)
+{
+	if (next_cpu < nr_cpu_ids) {
+#ifdef CONFIG_RFS_ACCEL
+		struct netdev_rx_queue *rxqueue;
+		struct rps_dev_flow_table *flow_table;
+		struct rps_dev_flow *old_rflow;
+		u32 flow_id;
+		u16 rxq_index;
+		int rc;
+
+		/* Should we steer this flow to a different hardware queue? */
+		if (!skb_rx_queue_recorded(skb) || !dev->rx_cpu_rmap ||
+		    !(dev->features & NETIF_F_NTUPLE))
+			goto out;
+		rxq_index = cpu_rmap_lookup_index(dev->rx_cpu_rmap, next_cpu);
+		if (rxq_index == skb_get_rx_queue(skb))
+			goto out;
+
+		rxqueue = dev->_rx + rxq_index;
+		flow_table = rcu_dereference(rxqueue->rps_flow_table);
+		if (!flow_table)
+			goto out;
+		flow_id = skb_get_hash(skb) & flow_table->mask;
+		rc = dev->netdev_ops->ndo_rx_flow_steer(dev, skb,
+							rxq_index, flow_id);
+		if (rc < 0)
+			goto out;
+		old_rflow = rflow;
+		rflow = &flow_table->flows[flow_id];
+		rflow->filter = rc;
+		if (old_rflow->filter == rflow->filter)
+			old_rflow->filter = RPS_NO_FILTER;
+	out:
+#endif
+		rflow->last_qtail =
+			per_cpu(softnet_data, next_cpu).input_queue_head;
+	}
+
+	rflow->cpu = next_cpu;
+	return rflow;
+}
+
+/*
+ * get_rps_cpu is called from netif_receive_skb and returns the target
+ * CPU from the RPS map of the receiving queue for a given skb.
+ * rcu_read_lock must be held on entry.
+ */
+static int get_rps_cpu(struct net_device *dev, struct sk_buff *skb,
+		       struct rps_dev_flow **rflowp)
+{
+	const struct rps_sock_flow_table *sock_flow_table;
+	struct netdev_rx_queue *rxqueue = dev->_rx;
+	struct rps_dev_flow_table *flow_table;
+	struct rps_map *map;
+	int cpu = -1;
+	u32 tcpu;
+	u32 hash;
+
+	if (skb_rx_queue_recorded(skb)) {
+		u16 index = skb_get_rx_queue(skb);
+
+		if (unlikely(index >= dev->real_num_rx_queues)) {
+			WARN_ONCE(dev->real_num_rx_queues > 1,
+				  "%s received packet on queue %u, but number "
+				  "of RX queues is %u\n",
+				  dev->name, index, dev->real_num_rx_queues);
+			goto done;
+		}
+		rxqueue += index;
+	}
+
+	/* Avoid computing hash if RFS/RPS is not active for this rxqueue */
+
+	flow_table = rcu_dereference(rxqueue->rps_flow_table);
+	map = rcu_dereference(rxqueue->rps_map);
+	if (!flow_table && !map)
+		goto done;
+
+	skb_reset_network_header(skb);
+	hash = skb_get_hash(skb);
+	if (!hash)
+		goto done;
+
+	sock_flow_table = rcu_dereference(rps_sock_flow_table);
+	if (flow_table && sock_flow_table) {
+		struct rps_dev_flow *rflow;
+		u32 next_cpu;
+		u32 ident;
+
+		/* First check into global flow table if there is a match */
+		ident = sock_flow_table->ents[hash & sock_flow_table->mask];
+		if ((ident ^ hash) & ~rps_cpu_mask)
+			goto try_rps;
+
+		next_cpu = ident & rps_cpu_mask;
+
+		/* OK, now we know there is a match,
+		 * we can look at the local (per receive queue) flow table
+		 */
+		rflow = &flow_table->flows[hash & flow_table->mask];
+		tcpu = rflow->cpu;
+
+		/*
+		 * If the desired CPU (where last recvmsg was done) is
+		 * different from current CPU (one in the rx-queue flow
+		 * table entry), switch if one of the following holds:
+		 *   - Current CPU is unset (>= nr_cpu_ids).
+		 *   - Current CPU is offline.
+		 *   - The current CPU's queue tail has advanced beyond the
+		 *     last packet that was enqueued using this table entry.
+		 *     This guarantees that all previous packets for the flow
+		 *     have been dequeued, thus preserving in order delivery.
+		 */
+		if (unlikely(tcpu != next_cpu) &&
+		    (tcpu >= nr_cpu_ids || !cpu_online(tcpu) ||
+		     ((int)(per_cpu(softnet_data, tcpu).input_queue_head -
+		      rflow->last_qtail)) >= 0)) {
+			tcpu = next_cpu;
+			rflow = set_rps_cpu(dev, skb, rflow, next_cpu);
+		}
+
+		if (tcpu < nr_cpu_ids && cpu_online(tcpu)) {
+			*rflowp = rflow;
+			cpu = tcpu;
+			goto done;
+		}
+	}
+
+try_rps:
+
+	if (map) {
+		tcpu = map->cpus[reciprocal_scale(hash, map->len)];
+		if (cpu_online(tcpu)) {
+			cpu = tcpu;
+			goto done;
+		}
+	}
+
+done:
+	return cpu;
+}
+
+#ifdef CONFIG_RFS_ACCEL
+
+/**
+ * rps_may_expire_flow - check whether an RFS hardware filter may be removed
+ * @dev: Device on which the filter was set
+ * @rxq_index: RX queue index
+ * @flow_id: Flow ID passed to ndo_rx_flow_steer()
+ * @filter_id: Filter ID returned by ndo_rx_flow_steer()
+ *
+ * Drivers that implement ndo_rx_flow_steer() should periodically call
+ * this function for each installed filter and remove the filters for
+ * which it returns %true.
+ */
+bool rps_may_expire_flow(struct net_device *dev, u16 rxq_index,
+			 u32 flow_id, u16 filter_id)
+{
+	struct netdev_rx_queue *rxqueue = dev->_rx + rxq_index;
+	struct rps_dev_flow_table *flow_table;
+	struct rps_dev_flow *rflow;
+	bool expire = true;
+	unsigned int cpu;
+
+	rcu_read_lock();
+	flow_table = rcu_dereference(rxqueue->rps_flow_table);
+	if (flow_table && flow_id <= flow_table->mask) {
+		rflow = &flow_table->flows[flow_id];
+		cpu = ACCESS_ONCE(rflow->cpu);
+		if (rflow->filter == filter_id && cpu < nr_cpu_ids &&
+		    ((int)(per_cpu(softnet_data, cpu).input_queue_head -
+			   rflow->last_qtail) <
+		     (int)(10 * flow_table->mask)))
+			expire = false;
+	}
+	rcu_read_unlock();
+	return expire;
+}
+EXPORT_SYMBOL(rps_may_expire_flow);
+
+#endif /* CONFIG_RFS_ACCEL */
+
+/* Called from hardirq (IPI) context */
+static void rps_trigger_softirq(void *data)
+{
+	struct softnet_data *sd = data;
+
+	____napi_schedule(sd, &sd->backlog);
+	sd->received_rps++;
+}
+
+#endif /* CONFIG_RPS */
+
+/*
+ * Check if this softnet_data structure is another cpu one
+ * If yes, queue it to our IPI list and return 1
+ * If no, return 0
+ */
+static int rps_ipi_queued(struct softnet_data *sd)
+{
+#ifdef CONFIG_RPS
+	struct softnet_data *mysd = this_cpu_ptr(&softnet_data);
+
+	if (sd != mysd) {
+		sd->rps_ipi_next = mysd->rps_ipi_list;
+		mysd->rps_ipi_list = sd;
+
+		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
+		return 1;
+	}
+#endif /* CONFIG_RPS */
+	return 0;
+}
+
+#ifdef CONFIG_NET_FLOW_LIMIT
+int netdev_flow_limit_table_len __read_mostly = (1 << 12);
+#endif
+
+static bool skb_flow_limit(struct sk_buff *skb, unsigned int qlen)
+{
+#ifdef CONFIG_NET_FLOW_LIMIT
+	struct sd_flow_limit *fl;
+	struct softnet_data *sd;
+	unsigned int old_flow, new_flow;
+
+	if (qlen < (netdev_max_backlog >> 1))
+		return false;
+
+	sd = this_cpu_ptr(&softnet_data);
+
+	rcu_read_lock();
+	fl = rcu_dereference(sd->flow_limit);
+	if (fl) {
+		new_flow = skb_get_hash(skb) & (fl->num_buckets - 1);
+		old_flow = fl->history[fl->history_head];
+		fl->history[fl->history_head] = new_flow;
+
+		fl->history_head++;
+		fl->history_head &= FLOW_LIMIT_HISTORY - 1;
+
+		if (likely(fl->buckets[old_flow]))
+			fl->buckets[old_flow]--;
+
+		if (++fl->buckets[new_flow] > (FLOW_LIMIT_HISTORY >> 1)) {
+			fl->count++;
+			rcu_read_unlock();
+			return true;
+		}
+	}
+	rcu_read_unlock();
+#endif
+	return false;
+}
+
+/*
+ * enqueue_to_backlog is called to queue an skb to a per CPU backlog
+ * queue (may be a remote CPU queue).
+ */
+static int enqueue_to_backlog(struct sk_buff *skb, int cpu,
+			      unsigned int *qtail)
+{
+	struct softnet_data *sd;
+	unsigned long flags;
+	unsigned int qlen;
+
+	sd = &per_cpu(softnet_data, cpu);
+
+	local_irq_save(flags);
+
+	rps_lock(sd);
+	qlen = skb_queue_len(&sd->input_pkt_queue);
+	if (qlen <= netdev_max_backlog && !skb_flow_limit(skb, qlen)) {
+		if (qlen) {
+enqueue:
+			__skb_queue_tail(&sd->input_pkt_queue, skb);
+			input_queue_tail_incr_save(sd, qtail);
+			rps_unlock(sd);
+			local_irq_restore(flags);
+			return NET_RX_SUCCESS;
+		}
+
+		/* Schedule NAPI for backlog device
+		 * We can use non atomic operation since we own the queue lock
+		 */
+		if (!__test_and_set_bit(NAPI_STATE_SCHED, &sd->backlog.state)) {
+			if (!rps_ipi_queued(sd))
+				____napi_schedule(sd, &sd->backlog);
+		}
+		goto enqueue;
+	}
+
+	sd->dropped++;
+	rps_unlock(sd);
+
+	local_irq_restore(flags);
+
+	atomic_long_inc(&skb->dev->rx_dropped);
+	kfree_skb(skb);
+	return NET_RX_DROP;
+}
+
+static int netif_rx_internal(struct sk_buff *skb)
+{
+	int ret;
+
+	net_timestamp_check(netdev_tstamp_prequeue, skb);
+
+	trace_netif_rx(skb);
+#ifdef CONFIG_RPS
+	if (static_key_false(&rps_needed)) {
+		struct rps_dev_flow voidflow, *rflow = &voidflow;
+		int cpu;
+
+		preempt_disable();
+		rcu_read_lock();
+
+		cpu = get_rps_cpu(skb->dev, skb, &rflow);
+		if (cpu < 0)
+			cpu = smp_processor_id();
+
+		ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
+
+		rcu_read_unlock();
+		preempt_enable();
+	} else
+#endif
+	{
+		unsigned int qtail;
+		ret = enqueue_to_backlog(skb, get_cpu(), &qtail);
+		put_cpu();
+	}
+	return ret;
+}
+
+/**
+ *	netif_rx	-	post buffer to the network code
+ *	@skb: buffer to post
+ *
+ *	This function receives a packet from a device driver and queues it for
+ *	the upper (protocol) levels to process.  It always succeeds. The buffer
+ *	may be dropped during processing for congestion control or by the
+ *	protocol layers.
+ *
+ *	return values:
+ *	NET_RX_SUCCESS	(no congestion)
+ *	NET_RX_DROP     (packet was dropped)
+ *
+ */
+
+int netif_rx(struct sk_buff *skb)
+{
+	trace_netif_rx_entry(skb);
+
+	return netif_rx_internal(skb);
+}
+EXPORT_SYMBOL(netif_rx);
+
+int netif_rx_ni(struct sk_buff *skb)
+{
+	int err;
+
+	trace_netif_rx_ni_entry(skb);
+
+	preempt_disable();
+	err = netif_rx_internal(skb);
+	if (local_softirq_pending())
+		do_softirq();
+	preempt_enable();
+
+	return err;
+}
+EXPORT_SYMBOL(netif_rx_ni);
+
+static void net_tx_action(struct softirq_action *h)
+{
+	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
+
+	if (sd->completion_queue) {
+		struct sk_buff *clist;
+
+		local_irq_disable();
+		clist = sd->completion_queue;
+		sd->completion_queue = NULL;
+		local_irq_enable();
+
+		while (clist) {
+			struct sk_buff *skb = clist;
+			clist = clist->next;
+
+			WARN_ON(atomic_read(&skb->users));
+			if (likely(get_kfree_skb_cb(skb)->reason == SKB_REASON_CONSUMED))
+				trace_consume_skb(skb);
+			else
+				trace_kfree_skb(skb, net_tx_action);
+			__kfree_skb(skb);
+		}
+	}
+
+	if (sd->output_queue) {
+		struct Qdisc *head;
+
+		local_irq_disable();
+		head = sd->output_queue;
+		sd->output_queue = NULL;
+		sd->output_queue_tailp = &sd->output_queue;
+		local_irq_enable();
+
+		while (head) {
+			struct Qdisc *q = head;
+			spinlock_t *root_lock;
+
+			head = head->next_sched;
+
+			root_lock = qdisc_lock(q);
+			if (spin_trylock(root_lock)) {
+				smp_mb__before_atomic();
+				clear_bit(__QDISC_STATE_SCHED,
+					  &q->state);
+				qdisc_run(q);
+				spin_unlock(root_lock);
+			} else {
+				if (!test_bit(__QDISC_STATE_DEACTIVATED,
+					      &q->state)) {
+					__netif_reschedule(q);
+				} else {
+					smp_mb__before_atomic();
+					clear_bit(__QDISC_STATE_SCHED,
+						  &q->state);
+				}
+			}
+		}
+	}
+}
+
+#if (defined(CONFIG_BRIDGE) || defined(CONFIG_BRIDGE_MODULE)) && \
+    (defined(CONFIG_ATM_LANE) || defined(CONFIG_ATM_LANE_MODULE))
+/* This hook is defined here for ATM LANE */
+int (*br_fdb_test_addr_hook)(struct net_device *dev,
+			     unsigned char *addr) __read_mostly;
+EXPORT_SYMBOL_GPL(br_fdb_test_addr_hook);
+#endif
+
+#ifdef CONFIG_NET_CLS_ACT
+/* TODO: Maybe we should just force sch_ingress to be compiled in
+ * when CONFIG_NET_CLS_ACT is? otherwise some useless instructions
+ * a compare and 2 stores extra right now if we dont have it on
+ * but have CONFIG_NET_CLS_ACT
+ * NOTE: This doesn't stop any functionality; if you dont have
+ * the ingress scheduler, you just can't add policies on ingress.
+ *
+ */
+static int ing_filter(struct sk_buff *skb, struct netdev_queue *rxq)
+{
+	struct net_device *dev = skb->dev;
+	u32 ttl = G_TC_RTTL(skb->tc_verd);
+	int result = TC_ACT_OK;
+	struct Qdisc *q;
+
+	if (unlikely(MAX_RED_LOOP < ttl++)) {
+		net_warn_ratelimited("Redir loop detected Dropping packet (%d->%d)\n",
+				     skb->skb_iif, dev->ifindex);
+		return TC_ACT_SHOT;
+	}
+
+	skb->tc_verd = SET_TC_RTTL(skb->tc_verd, ttl);
+	skb->tc_verd = SET_TC_AT(skb->tc_verd, AT_INGRESS);
+
+	q = rcu_dereference(rxq->qdisc);
+	if (q != &noop_qdisc) {
+		spin_lock(qdisc_lock(q));
+		if (likely(!test_bit(__QDISC_STATE_DEACTIVATED, &q->state)))
+			result = qdisc_enqueue_root(skb, q);
+		spin_unlock(qdisc_lock(q));
+	}
+
+	return result;
+}
+
+static inline struct sk_buff *handle_ing(struct sk_buff *skb,
+					 struct packet_type **pt_prev,
+					 int *ret, struct net_device *orig_dev)
+{
+	struct netdev_queue *rxq = rcu_dereference(skb->dev->ingress_queue);
+
+	if (!rxq || rcu_access_pointer(rxq->qdisc) == &noop_qdisc)
+		return skb;
+
+	if (*pt_prev) {
+		*ret = deliver_skb(skb, *pt_prev, orig_dev);
+		*pt_prev = NULL;
+	}
+
+	switch (ing_filter(skb, rxq)) {
+	case TC_ACT_SHOT:
+	case TC_ACT_STOLEN:
+		kfree_skb(skb);
+		return NULL;
+	}
+
+	return skb;
+}
+#endif
+
+/**
+ *	netdev_rx_handler_register - register receive handler
+ *	@dev: device to register a handler for
+ *	@rx_handler: receive handler to register
+ *	@rx_handler_data: data pointer that is used by rx handler
+ *
+ *	Register a receive handler for a device. This handler will then be
+ *	called from __netif_receive_skb. A negative errno code is returned
+ *	on a failure.
+ *
+ *	The caller must hold the rtnl_mutex.
+ *
+ *	For a general description of rx_handler, see enum rx_handler_result.
+ */
+int netdev_rx_handler_register(struct net_device *dev,
+			       rx_handler_func_t *rx_handler,
+			       void *rx_handler_data)
+{
+	ASSERT_RTNL();
+
+	if (dev->rx_handler)
+		return -EBUSY;
+
+	/* Note: rx_handler_data must be set before rx_handler */
+	rcu_assign_pointer(dev->rx_handler_data, rx_handler_data);
+	rcu_assign_pointer(dev->rx_handler, rx_handler);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(netdev_rx_handler_register);
+
+/**
+ *	netdev_rx_handler_unregister - unregister receive handler
+ *	@dev: device to unregister a handler from
+ *
+ *	Unregister a receive handler from a device.
+ *
+ *	The caller must hold the rtnl_mutex.
+ */
+void netdev_rx_handler_unregister(struct net_device *dev)
+{
+
+	ASSERT_RTNL();
+	RCU_INIT_POINTER(dev->rx_handler, NULL);
+	/* a reader seeing a non NULL rx_handler in a rcu_read_lock()
+	 * section has a guarantee to see a non NULL rx_handler_data
+	 * as well.
+	 */
+	synchronize_net();
+	RCU_INIT_POINTER(dev->rx_handler_data, NULL);
+}
+EXPORT_SYMBOL_GPL(netdev_rx_handler_unregister);
+
+/*
+ * Limit the use of PFMEMALLOC reserves to those protocols that implement
+ * the special handling of PFMEMALLOC skbs.
+ */
+static bool skb_pfmemalloc_protocol(struct sk_buff *skb)
+{
+	switch (skb->protocol) {
+	case htons(ETH_P_ARP):
+	case htons(ETH_P_IP):
+	case htons(ETH_P_IPV6):
+	case htons(ETH_P_8021Q):
+	case htons(ETH_P_8021AD):
+		return true;
+	default:
+		return false;
+	}
+}
+
+static int __netif_receive_skb_core(struct sk_buff *skb, bool pfmemalloc)
+{
+	struct packet_type *ptype, *pt_prev;
+	rx_handler_func_t *rx_handler;
+	struct net_device *orig_dev;
+	bool deliver_exact = false;
+	int ret = NET_RX_DROP;
+	__be16 type;
+
+	net_timestamp_check(!netdev_tstamp_prequeue, skb);
+
+	trace_netif_receive_skb(skb);
+
+	orig_dev = skb->dev;
+
+	skb_reset_network_header(skb);
+	if (!skb_transport_header_was_set(skb))
+		skb_reset_transport_header(skb);
+	skb_reset_mac_len(skb);
+
+	pt_prev = NULL;
+
+	rcu_read_lock();
+
+another_round:
+	skb->skb_iif = skb->dev->ifindex;
+
+	__this_cpu_inc(softnet_data.processed);
+
+	if (skb->protocol == cpu_to_be16(ETH_P_8021Q) ||
+	    skb->protocol == cpu_to_be16(ETH_P_8021AD)) {
+		skb = skb_vlan_untag(skb);
+		if (unlikely(!skb))
+			goto unlock;
+	}
+
+#ifdef CONFIG_NET_CLS_ACT
+	if (skb->tc_verd & TC_NCLS) {
+		skb->tc_verd = CLR_TC_NCLS(skb->tc_verd);
+		goto ncls;
+	}
+#endif
+
+	if (pfmemalloc)
+		goto skip_taps;
+
+	list_for_each_entry_rcu(ptype, &ptype_all, list) {
+		if (pt_prev)
+			ret = deliver_skb(skb, pt_prev, orig_dev);
+		pt_prev = ptype;
+	}
+
+	list_for_each_entry_rcu(ptype, &skb->dev->ptype_all, list) {
+		if (pt_prev)
+			ret = deliver_skb(skb, pt_prev, orig_dev);
+		pt_prev = ptype;
+	}
+
+skip_taps:
+#ifdef CONFIG_NET_CLS_ACT
+	if (static_key_false(&ingress_needed)) {
+		skb = handle_ing(skb, &pt_prev, &ret, orig_dev);
+		if (!skb)
+			goto unlock;
+	}
+
+	skb->tc_verd = 0;
+ncls:
+#endif
+	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
+		goto drop;
+
+	if (skb_vlan_tag_present(skb)) {
+		if (pt_prev) {
+			ret = deliver_skb(skb, pt_prev, orig_dev);
+			pt_prev = NULL;
+		}
+		if (vlan_do_receive(&skb))
+			goto another_round;
+		else if (unlikely(!skb))
+			goto unlock;
+	}
+
+	rx_handler = rcu_dereference(skb->dev->rx_handler);
+	if (rx_handler) {
+		if (pt_prev) {
+			ret = deliver_skb(skb, pt_prev, orig_dev);
+			pt_prev = NULL;
+		}
+		switch (rx_handler(&skb)) {
+		case RX_HANDLER_CONSUMED:
+			ret = NET_RX_SUCCESS;
+			goto unlock;
+		case RX_HANDLER_ANOTHER:
+			goto another_round;
+		case RX_HANDLER_EXACT:
+			deliver_exact = true;
+		case RX_HANDLER_PASS:
+			break;
+		default:
+			BUG();
+		}
+	}
+
+	if (unlikely(skb_vlan_tag_present(skb))) {
+		if (skb_vlan_tag_get_id(skb))
+			skb->pkt_type = PACKET_OTHERHOST;
+		/* Note: we might in the future use prio bits
+		 * and set skb->priority like in vlan_do_receive()
+		 * For the time being, just ignore Priority Code Point
+		 */
+		skb->vlan_tci = 0;
+	}
+
+	type = skb->protocol;
+
+	/* deliver only exact match when indicated */
+	if (likely(!deliver_exact)) {
+		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
+				       &ptype_base[ntohs(type) &
+						   PTYPE_HASH_MASK]);
+	}
+
+	deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
+			       &orig_dev->ptype_specific);
+
+	if (unlikely(skb->dev != orig_dev)) {
+		deliver_ptype_list_skb(skb, &pt_prev, orig_dev, type,
+				       &skb->dev->ptype_specific);
+	}
+
+	if (pt_prev) {
+		if (unlikely(skb_orphan_frags(skb, GFP_ATOMIC)))
+			goto drop;
+		else
+			ret = pt_prev->func(skb, skb->dev, pt_prev, orig_dev);
+	} else {
+drop:
+		atomic_long_inc(&skb->dev->rx_dropped);
+		kfree_skb(skb);
+		/* Jamal, now you will not able to escape explaining
+		 * me how you were going to use this. :-)
+		 */
+		ret = NET_RX_DROP;
+	}
+
+unlock:
+	rcu_read_unlock();
+	return ret;
+}
+
+static int __netif_receive_skb(struct sk_buff *skb)
+{
+	int ret;
+
+	if (sk_memalloc_socks() && skb_pfmemalloc(skb)) {
+		unsigned long pflags = current->flags;
+
+		/*
+		 * PFMEMALLOC skbs are special, they should
+		 * - be delivered to SOCK_MEMALLOC sockets only
+		 * - stay away from userspace
+		 * - have bounded memory usage
+		 *
+		 * Use PF_MEMALLOC as this saves us from propagating the allocation
+		 * context down to all allocation sites.
+		 */
+		current->flags |= PF_MEMALLOC;
+		ret = __netif_receive_skb_core(skb, true);
+		tsk_restore_flags(current, pflags, PF_MEMALLOC);
+	} else
+		ret = __netif_receive_skb_core(skb, false);
+
+	return ret;
+}
+
+static int netif_receive_skb_internal(struct sk_buff *skb)
+{
+	net_timestamp_check(netdev_tstamp_prequeue, skb);
+
+	if (skb_defer_rx_timestamp(skb))
+		return NET_RX_SUCCESS;
+
+#ifdef CONFIG_RPS
+	if (static_key_false(&rps_needed)) {
+		struct rps_dev_flow voidflow, *rflow = &voidflow;
+		int cpu, ret;
+
+		rcu_read_lock();
+
+		cpu = get_rps_cpu(skb->dev, skb, &rflow);
+
+		if (cpu >= 0) {
+			ret = enqueue_to_backlog(skb, cpu, &rflow->last_qtail);
+			rcu_read_unlock();
+			return ret;
+		}
+		rcu_read_unlock();
+	}
+#endif
+	return __netif_receive_skb(skb);
+}
+
+/**
+ *	netif_receive_skb - process receive buffer from network
+ *	@skb: buffer to process
+ *
+ *	netif_receive_skb() is the main receive data processing function.
+ *	It always succeeds. The buffer may be dropped during processing
+ *	for congestion control or by the protocol layers.
+ *
+ *	This function may only be called from softirq context and interrupts
+ *	should be enabled.
+ *
+ *	Return values (usually ignored):
+ *	NET_RX_SUCCESS: no congestion
+ *	NET_RX_DROP: packet was dropped
+ */
+int netif_receive_skb_sk(struct sock *sk, struct sk_buff *skb)
+{
+	trace_netif_receive_skb_entry(skb);
+
+	return netif_receive_skb_internal(skb);
+}
+EXPORT_SYMBOL(netif_receive_skb_sk);
+
+/* Network device is going away, flush any packets still pending
+ * Called with irqs disabled.
+ */
+static void flush_backlog(void *arg)
+{
+	struct net_device *dev = arg;
+	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
+	struct sk_buff *skb, *tmp;
+
+	rps_lock(sd);
+	skb_queue_walk_safe(&sd->input_pkt_queue, skb, tmp) {
+		if (skb->dev == dev) {
+			__skb_unlink(skb, &sd->input_pkt_queue);
+			kfree_skb(skb);
+			input_queue_head_incr(sd);
+		}
+	}
+	rps_unlock(sd);
+
+	skb_queue_walk_safe(&sd->process_queue, skb, tmp) {
+		if (skb->dev == dev) {
+			__skb_unlink(skb, &sd->process_queue);
+			kfree_skb(skb);
+			input_queue_head_incr(sd);
+		}
+	}
+}
+
+static int napi_gro_complete(struct sk_buff *skb)
+{
+	struct packet_offload *ptype;
+	__be16 type = skb->protocol;
+	struct list_head *head = &offload_base;
+	int err = -ENOENT;
+
+	BUILD_BUG_ON(sizeof(struct napi_gro_cb) > sizeof(skb->cb));
+
+	if (NAPI_GRO_CB(skb)->count == 1) {
+		skb_shinfo(skb)->gso_size = 0;
+		goto out;
+	}
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(ptype, head, list) {
+		if (ptype->type != type || !ptype->callbacks.gro_complete)
+			continue;
+
+		err = ptype->callbacks.gro_complete(skb, 0);
+		break;
+	}
+	rcu_read_unlock();
+
+	if (err) {
+		WARN_ON(&ptype->list == head);
+		kfree_skb(skb);
+		return NET_RX_SUCCESS;
+	}
+
+out:
+	return netif_receive_skb_internal(skb);
+}
+
+/* napi->gro_list contains packets ordered by age.
+ * youngest packets at the head of it.
+ * Complete skbs in reverse order to reduce latencies.
+ */
+void napi_gro_flush(struct napi_struct *napi, bool flush_old)
+{
+	struct sk_buff *skb, *prev = NULL;
+
+	/* scan list and build reverse chain */
+	for (skb = napi->gro_list; skb != NULL; skb = skb->next) {
+		skb->prev = prev;
+		prev = skb;
+	}
+
+	for (skb = prev; skb; skb = prev) {
+		skb->next = NULL;
+
+		if (flush_old && NAPI_GRO_CB(skb)->age == jiffies)
+			return;
+
+		prev = skb->prev;
+		napi_gro_complete(skb);
+		napi->gro_count--;
+	}
+
+	napi->gro_list = NULL;
+}
+EXPORT_SYMBOL(napi_gro_flush);
+
+static void gro_list_prepare(struct napi_struct *napi, struct sk_buff *skb)
+{
+	struct sk_buff *p;
+	unsigned int maclen = skb->dev->hard_header_len;
+	u32 hash = skb_get_hash_raw(skb);
+
+	for (p = napi->gro_list; p; p = p->next) {
+		unsigned long diffs;
+
+		NAPI_GRO_CB(p)->flush = 0;
+
+		if (hash != skb_get_hash_raw(p)) {
+			NAPI_GRO_CB(p)->same_flow = 0;
+			continue;
+		}
+
+		diffs = (unsigned long)p->dev ^ (unsigned long)skb->dev;
+		diffs |= p->vlan_tci ^ skb->vlan_tci;
+		if (maclen == ETH_HLEN)
+			diffs |= compare_ether_header(skb_mac_header(p),
+						      skb_mac_header(skb));
+		else if (!diffs)
+			diffs = memcmp(skb_mac_header(p),
+				       skb_mac_header(skb),
+				       maclen);
+		NAPI_GRO_CB(p)->same_flow = !diffs;
+	}
+}
+
+static void skb_gro_reset_offset(struct sk_buff *skb)
+{
+	const struct skb_shared_info *pinfo = skb_shinfo(skb);
+	const skb_frag_t *frag0 = &pinfo->frags[0];
+
+	NAPI_GRO_CB(skb)->data_offset = 0;
+	NAPI_GRO_CB(skb)->frag0 = NULL;
+	NAPI_GRO_CB(skb)->frag0_len = 0;
+
+	if (skb_mac_header(skb) == skb_tail_pointer(skb) &&
+	    pinfo->nr_frags &&
+	    !PageHighMem(skb_frag_page(frag0))) {
+		NAPI_GRO_CB(skb)->frag0 = skb_frag_address(frag0);
+		NAPI_GRO_CB(skb)->frag0_len = skb_frag_size(frag0);
+	}
+}
+
+static void gro_pull_from_frag0(struct sk_buff *skb, int grow)
+{
+	struct skb_shared_info *pinfo = skb_shinfo(skb);
+
+	BUG_ON(skb->end - skb->tail < grow);
+
+	memcpy(skb_tail_pointer(skb), NAPI_GRO_CB(skb)->frag0, grow);
+
+	skb->data_len -= grow;
+	skb->tail += grow;
+
+	pinfo->frags[0].page_offset += grow;
+	skb_frag_size_sub(&pinfo->frags[0], grow);
+
+	if (unlikely(!skb_frag_size(&pinfo->frags[0]))) {
+		skb_frag_unref(skb, 0);
+		memmove(pinfo->frags, pinfo->frags + 1,
+			--pinfo->nr_frags * sizeof(pinfo->frags[0]));
+	}
+}
+
+static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
+{
+	struct sk_buff **pp = NULL;
+	struct packet_offload *ptype;
+	__be16 type = skb->protocol;
+	struct list_head *head = &offload_base;
+	int same_flow;
+	enum gro_result ret;
+	int grow;
+
+	if (!(skb->dev->features & NETIF_F_GRO))
+		goto normal;
+
+	if (skb_is_gso(skb) || skb_has_frag_list(skb) || skb->csum_bad)
+		goto normal;
+
+	gro_list_prepare(napi, skb);
+
+	rcu_read_lock();
+	list_for_each_entry_rcu(ptype, head, list) {
+		if (ptype->type != type || !ptype->callbacks.gro_receive)
+			continue;
+
+		skb_set_network_header(skb, skb_gro_offset(skb));
+		skb_reset_mac_len(skb);
+		NAPI_GRO_CB(skb)->same_flow = 0;
+		NAPI_GRO_CB(skb)->flush = 0;
+		NAPI_GRO_CB(skb)->free = 0;
+		NAPI_GRO_CB(skb)->udp_mark = 0;
+		NAPI_GRO_CB(skb)->gro_remcsum_start = 0;
+
+		/* Setup for GRO checksum validation */
+		switch (skb->ip_summed) {
+		case CHECKSUM_COMPLETE:
+			NAPI_GRO_CB(skb)->csum = skb->csum;
+			NAPI_GRO_CB(skb)->csum_valid = 1;
+			NAPI_GRO_CB(skb)->csum_cnt = 0;
+			break;
+		case CHECKSUM_UNNECESSARY:
+			NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1;
+			NAPI_GRO_CB(skb)->csum_valid = 0;
+			break;
+		default:
+			NAPI_GRO_CB(skb)->csum_cnt = 0;
+			NAPI_GRO_CB(skb)->csum_valid = 0;
+		}
+
+		pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
+		break;
+	}
+	rcu_read_unlock();
+
+	if (&ptype->list == head)
+		goto normal;
+
+	same_flow = NAPI_GRO_CB(skb)->same_flow;
+	ret = NAPI_GRO_CB(skb)->free ? GRO_MERGED_FREE : GRO_MERGED;
+
+	if (pp) {
+		struct sk_buff *nskb = *pp;
+
+		*pp = nskb->next;
+		nskb->next = NULL;
+		napi_gro_complete(nskb);
+		napi->gro_count--;
+	}
+
+	if (same_flow)
+		goto ok;
+
+	if (NAPI_GRO_CB(skb)->flush)
+		goto normal;
+
+	if (unlikely(napi->gro_count >= MAX_GRO_SKBS)) {
+		struct sk_buff *nskb = napi->gro_list;
+
+		/* locate the end of the list to select the 'oldest' flow */
+		while (nskb->next) {
+			pp = &nskb->next;
+			nskb = *pp;
+		}
+		*pp = NULL;
+		nskb->next = NULL;
+		napi_gro_complete(nskb);
+	} else {
+		napi->gro_count++;
+	}
+	NAPI_GRO_CB(skb)->count = 1;
+	NAPI_GRO_CB(skb)->age = jiffies;
+	NAPI_GRO_CB(skb)->last = skb;
+	skb_shinfo(skb)->gso_size = skb_gro_len(skb);
+	skb->next = napi->gro_list;
+	napi->gro_list = skb;
+	ret = GRO_HELD;
+
+pull:
+	grow = skb_gro_offset(skb) - skb_headlen(skb);
+	if (grow > 0)
+		gro_pull_from_frag0(skb, grow);
+ok:
+	return ret;
+
+normal:
+	ret = GRO_NORMAL;
+	goto pull;
+}
+
+struct packet_offload *gro_find_receive_by_type(__be16 type)
+{
+	struct list_head *offload_head = &offload_base;
+	struct packet_offload *ptype;
+
+	list_for_each_entry_rcu(ptype, offload_head, list) {
+		if (ptype->type != type || !ptype->callbacks.gro_receive)
+			continue;
+		return ptype;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(gro_find_receive_by_type);
+
+struct packet_offload *gro_find_complete_by_type(__be16 type)
+{
+	struct list_head *offload_head = &offload_base;
+	struct packet_offload *ptype;
+
+	list_for_each_entry_rcu(ptype, offload_head, list) {
+		if (ptype->type != type || !ptype->callbacks.gro_complete)
+			continue;
+		return ptype;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL(gro_find_complete_by_type);
+
+static gro_result_t napi_skb_finish(gro_result_t ret, struct sk_buff *skb)
+{
+	switch (ret) {
+	case GRO_NORMAL:
+		if (netif_receive_skb_internal(skb))
+			ret = GRO_DROP;
+		break;
+
+	case GRO_DROP:
+		kfree_skb(skb);
+		break;
+
+	case GRO_MERGED_FREE:
+		if (NAPI_GRO_CB(skb)->free == NAPI_GRO_FREE_STOLEN_HEAD)
+			kmem_cache_free(skbuff_head_cache, skb);
+		else
+			__kfree_skb(skb);
+		break;
+
+	case GRO_HELD:
+	case GRO_MERGED:
+		break;
+	}
+
+	return ret;
+}
+
+gro_result_t napi_gro_receive(struct napi_struct *napi, struct sk_buff *skb)
+{
+	trace_napi_gro_receive_entry(skb);
+
+	skb_gro_reset_offset(skb);
+
+	return napi_skb_finish(dev_gro_receive(napi, skb), skb);
+}
+EXPORT_SYMBOL(napi_gro_receive);
+
+static void napi_reuse_skb(struct napi_struct *napi, struct sk_buff *skb)
+{
+	if (unlikely(skb->pfmemalloc)) {
+		consume_skb(skb);
+		return;
+	}
+	__skb_pull(skb, skb_headlen(skb));
+	/* restore the reserve we had after netdev_alloc_skb_ip_align() */
+	skb_reserve(skb, NET_SKB_PAD + NET_IP_ALIGN - skb_headroom(skb));
+	skb->vlan_tci = 0;
+	skb->dev = napi->dev;
+	skb->skb_iif = 0;
+	skb->encapsulation = 0;
+	skb_shinfo(skb)->gso_type = 0;
+	skb->truesize = SKB_TRUESIZE(skb_end_offset(skb));
+
+	napi->skb = skb;
+}
+
+struct sk_buff *napi_get_frags(struct napi_struct *napi)
+{
+	struct sk_buff *skb = napi->skb;
+
+	if (!skb) {
+		skb = napi_alloc_skb(napi, GRO_MAX_HEAD);
+		napi->skb = skb;
+	}
+	return skb;
+}
+EXPORT_SYMBOL(napi_get_frags);
+
+static gro_result_t napi_frags_finish(struct napi_struct *napi,
+				      struct sk_buff *skb,
+				      gro_result_t ret)
+{
+	switch (ret) {
+	case GRO_NORMAL:
+	case GRO_HELD:
+		__skb_push(skb, ETH_HLEN);
+		skb->protocol = eth_type_trans(skb, skb->dev);
+		if (ret == GRO_NORMAL && netif_receive_skb_internal(skb))
+			ret = GRO_DROP;
+		break;
+
+	case GRO_DROP:
+	case GRO_MERGED_FREE:
+		napi_reuse_skb(napi, skb);
+		break;
+
+	case GRO_MERGED:
+		break;
+	}
+
+	return ret;
+}
+
+/* Upper GRO stack assumes network header starts at gro_offset=0
+ * Drivers could call both napi_gro_frags() and napi_gro_receive()
+ * We copy ethernet header into skb->data to have a common layout.
+ */
+static struct sk_buff *napi_frags_skb(struct napi_struct *napi)
+{
+	struct sk_buff *skb = napi->skb;
+	const struct ethhdr *eth;
+	unsigned int hlen = sizeof(*eth);
+
+	napi->skb = NULL;
+
+	skb_reset_mac_header(skb);
+	skb_gro_reset_offset(skb);
+
+	eth = skb_gro_header_fast(skb, 0);
+	if (unlikely(skb_gro_header_hard(skb, hlen))) {
+		eth = skb_gro_header_slow(skb, hlen, 0);
+		if (unlikely(!eth)) {
+			napi_reuse_skb(napi, skb);
+			return NULL;
+		}
+	} else {
+		gro_pull_from_frag0(skb, hlen);
+		NAPI_GRO_CB(skb)->frag0 += hlen;
+		NAPI_GRO_CB(skb)->frag0_len -= hlen;
+	}
+	__skb_pull(skb, hlen);
+
+	/*
+	 * This works because the only protocols we care about don't require
+	 * special handling.
+	 * We'll fix it up properly in napi_frags_finish()
+	 */
+	skb->protocol = eth->h_proto;
+
+	return skb;
+}
+
+gro_result_t napi_gro_frags(struct napi_struct *napi)
+{
+	struct sk_buff *skb = napi_frags_skb(napi);
+
+	if (!skb)
+		return GRO_DROP;
+
+	trace_napi_gro_frags_entry(skb);
+
+	return napi_frags_finish(napi, skb, dev_gro_receive(napi, skb));
+}
+EXPORT_SYMBOL(napi_gro_frags);
+
+/* Compute the checksum from gro_offset and return the folded value
+ * after adding in any pseudo checksum.
+ */
+__sum16 __skb_gro_checksum_complete(struct sk_buff *skb)
+{
+	__wsum wsum;
+	__sum16 sum;
+
+	wsum = skb_checksum(skb, skb_gro_offset(skb), skb_gro_len(skb), 0);
+
+	/* NAPI_GRO_CB(skb)->csum holds pseudo checksum */
+	sum = csum_fold(csum_add(NAPI_GRO_CB(skb)->csum, wsum));
+	if (likely(!sum)) {
+		if (unlikely(skb->ip_summed == CHECKSUM_COMPLETE) &&
+		    !skb->csum_complete_sw)
+			netdev_rx_csum_fault(skb->dev);
+	}
+
+	NAPI_GRO_CB(skb)->csum = wsum;
+	NAPI_GRO_CB(skb)->csum_valid = 1;
+
+	return sum;
+}
+EXPORT_SYMBOL(__skb_gro_checksum_complete);
+
+/*
+ * net_rps_action_and_irq_enable sends any pending IPI's for rps.
+ * Note: called with local irq disabled, but exits with local irq enabled.
+ */
+static void net_rps_action_and_irq_enable(struct softnet_data *sd)
+{
+#ifdef CONFIG_RPS
+	struct softnet_data *remsd = sd->rps_ipi_list;
+
+	if (remsd) {
+		sd->rps_ipi_list = NULL;
+
+		local_irq_enable();
+
+		/* Send pending IPI's to kick RPS processing on remote cpus. */
+		while (remsd) {
+			struct softnet_data *next = remsd->rps_ipi_next;
+
+			if (cpu_online(remsd->cpu))
+				smp_call_function_single_async(remsd->cpu,
+							   &remsd->csd);
+			remsd = next;
+		}
+	} else
+#endif
+		local_irq_enable();
+}
+
+static bool sd_has_rps_ipi_waiting(struct softnet_data *sd)
+{
+#ifdef CONFIG_RPS
+	return sd->rps_ipi_list != NULL;
+#else
+	return false;
+#endif
+}
+
+static int process_backlog(struct napi_struct *napi, int quota)
+{
+	int work = 0;
+	struct softnet_data *sd = container_of(napi, struct softnet_data, backlog);
+
+	/* Check if we have pending ipi, its better to send them now,
+	 * not waiting net_rx_action() end.
+	 */
+	if (sd_has_rps_ipi_waiting(sd)) {
+		local_irq_disable();
+		net_rps_action_and_irq_enable(sd);
+	}
+
+	napi->weight = weight_p;
+	local_irq_disable();
+	while (1) {
+		struct sk_buff *skb;
+
+		while ((skb = __skb_dequeue(&sd->process_queue))) {
+			local_irq_enable();
+			__netif_receive_skb(skb);
+			local_irq_disable();
+			input_queue_head_incr(sd);
+			if (++work >= quota) {
+				local_irq_enable();
+				return work;
+			}
+		}
+
+		rps_lock(sd);
+		if (skb_queue_empty(&sd->input_pkt_queue)) {
+			/*
+			 * Inline a custom version of __napi_complete().
+			 * only current cpu owns and manipulates this napi,
+			 * and NAPI_STATE_SCHED is the only possible flag set
+			 * on backlog.
+			 * We can use a plain write instead of clear_bit(),
+			 * and we dont need an smp_mb() memory barrier.
+			 */
+			napi->state = 0;
+			rps_unlock(sd);
+
+			break;
+		}
+
+		skb_queue_splice_tail_init(&sd->input_pkt_queue,
+					   &sd->process_queue);
+		rps_unlock(sd);
+	}
+	local_irq_enable();
+
+	return work;
+}
+
+/**
+ * __napi_schedule - schedule for receive
+ * @n: entry to schedule
+ *
+ * The entry's receive function will be scheduled to run.
+ * Consider using __napi_schedule_irqoff() if hard irqs are masked.
+ */
+void __napi_schedule(struct napi_struct *n)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	____napi_schedule(this_cpu_ptr(&softnet_data), n);
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL(__napi_schedule);
+
+/**
+ * __napi_schedule_irqoff - schedule for receive
+ * @n: entry to schedule
+ *
+ * Variant of __napi_schedule() assuming hard irqs are masked
+ */
+void __napi_schedule_irqoff(struct napi_struct *n)
+{
+	____napi_schedule(this_cpu_ptr(&softnet_data), n);
+}
+EXPORT_SYMBOL(__napi_schedule_irqoff);
+
+void __napi_complete(struct napi_struct *n)
+{
+	BUG_ON(!test_bit(NAPI_STATE_SCHED, &n->state));
+
+	list_del_init(&n->poll_list);
+	smp_mb__before_atomic();
+	clear_bit(NAPI_STATE_SCHED, &n->state);
+}
+EXPORT_SYMBOL(__napi_complete);
+
+void napi_complete_done(struct napi_struct *n, int work_done)
+{
+	unsigned long flags;
+
+	/*
+	 * don't let napi dequeue from the cpu poll list
+	 * just in case its running on a different cpu
+	 */
+	if (unlikely(test_bit(NAPI_STATE_NPSVC, &n->state)))
+		return;
+
+	if (n->gro_list) {
+		unsigned long timeout = 0;
+
+		if (work_done)
+			timeout = n->dev->gro_flush_timeout;
+
+		if (timeout)
+			hrtimer_start(&n->timer, ns_to_ktime(timeout),
+				      HRTIMER_MODE_REL_PINNED);
+		else
+			napi_gro_flush(n, false);
+	}
+	if (likely(list_empty(&n->poll_list))) {
+		WARN_ON_ONCE(!test_and_clear_bit(NAPI_STATE_SCHED, &n->state));
+	} else {
+		/* If n->poll_list is not empty, we need to mask irqs */
+		local_irq_save(flags);
+		__napi_complete(n);
+		local_irq_restore(flags);
+	}
+}
+EXPORT_SYMBOL(napi_complete_done);
+
+/* must be called under rcu_read_lock(), as we dont take a reference */
+struct napi_struct *napi_by_id(unsigned int napi_id)
+{
+	unsigned int hash = napi_id % HASH_SIZE(napi_hash);
+	struct napi_struct *napi;
+
+	hlist_for_each_entry_rcu(napi, &napi_hash[hash], napi_hash_node)
+		if (napi->napi_id == napi_id)
+			return napi;
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(napi_by_id);
+
+void napi_hash_add(struct napi_struct *napi)
+{
+	if (!test_and_set_bit(NAPI_STATE_HASHED, &napi->state)) {
+
+		spin_lock(&napi_hash_lock);
+
+		/* 0 is not a valid id, we also skip an id that is taken
+		 * we expect both events to be extremely rare
+		 */
+		napi->napi_id = 0;
+		while (!napi->napi_id) {
+			napi->napi_id = ++napi_gen_id;
+			if (napi_by_id(napi->napi_id))
+				napi->napi_id = 0;
+		}
+
+		hlist_add_head_rcu(&napi->napi_hash_node,
+			&napi_hash[napi->napi_id % HASH_SIZE(napi_hash)]);
+
+		spin_unlock(&napi_hash_lock);
+	}
+}
+EXPORT_SYMBOL_GPL(napi_hash_add);
+
+/* Warning : caller is responsible to make sure rcu grace period
+ * is respected before freeing memory containing @napi
+ */
+void napi_hash_del(struct napi_struct *napi)
+{
+	spin_lock(&napi_hash_lock);
+
+	if (test_and_clear_bit(NAPI_STATE_HASHED, &napi->state))
+		hlist_del_rcu(&napi->napi_hash_node);
+
+	spin_unlock(&napi_hash_lock);
+}
+EXPORT_SYMBOL_GPL(napi_hash_del);
+
+static enum hrtimer_restart napi_watchdog(struct hrtimer *timer)
+{
+	struct napi_struct *napi;
+
+	napi = container_of(timer, struct napi_struct, timer);
+	if (napi->gro_list)
+		napi_schedule(napi);
+
+	return HRTIMER_NORESTART;
+}
+
+void netif_napi_add(struct net_device *dev, struct napi_struct *napi,
+		    int (*poll)(struct napi_struct *, int), int weight)
+{
+	INIT_LIST_HEAD(&napi->poll_list);
+	hrtimer_init(&napi->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_PINNED);
+	napi->timer.function = napi_watchdog;
+	napi->gro_count = 0;
+	napi->gro_list = NULL;
+	napi->skb = NULL;
+	napi->poll = poll;
+	if (weight > NAPI_POLL_WEIGHT)
+		pr_err_once("netif_napi_add() called with weight %d on device %s\n",
+			    weight, dev->name);
+	napi->weight = weight;
+	list_add(&napi->dev_list, &dev->napi_list);
+	napi->dev = dev;
+#ifdef CONFIG_NETPOLL
+	spin_lock_init(&napi->poll_lock);
+	napi->poll_owner = -1;
+#endif
+	set_bit(NAPI_STATE_SCHED, &napi->state);
+}
+EXPORT_SYMBOL(netif_napi_add);
+
+void napi_disable(struct napi_struct *n)
+{
+	might_sleep();
+	set_bit(NAPI_STATE_DISABLE, &n->state);
+
+	while (test_and_set_bit(NAPI_STATE_SCHED, &n->state))
+		msleep(1);
+
+	hrtimer_cancel(&n->timer);
+
+	clear_bit(NAPI_STATE_DISABLE, &n->state);
+}
+EXPORT_SYMBOL(napi_disable);
+
+void netif_napi_del(struct napi_struct *napi)
+{
+	list_del_init(&napi->dev_list);
+	napi_free_frags(napi);
+
+	kfree_skb_list(napi->gro_list);
+	napi->gro_list = NULL;
+	napi->gro_count = 0;
+}
+EXPORT_SYMBOL(netif_napi_del);
+
+static int napi_poll(struct napi_struct *n, struct list_head *repoll)
+{
+	void *have;
+	int work, weight;
+
+	list_del_init(&n->poll_list);
+
+	have = netpoll_poll_lock(n);
+
+	weight = n->weight;
+
+	/* This NAPI_STATE_SCHED test is for avoiding a race
+	 * with netpoll's poll_napi().  Only the entity which
+	 * obtains the lock and sees NAPI_STATE_SCHED set will
+	 * actually make the ->poll() call.  Therefore we avoid
+	 * accidentally calling ->poll() when NAPI is not scheduled.
+	 */
+	work = 0;
+	if (test_bit(NAPI_STATE_SCHED, &n->state)) {
+		work = n->poll(n, weight);
+		trace_napi_poll(n);
+	}
+
+	WARN_ON_ONCE(work > weight);
+
+	if (likely(work < weight))
+		goto out_unlock;
+
+	/* Drivers must not modify the NAPI state if they
+	 * consume the entire weight.  In such cases this code
+	 * still "owns" the NAPI instance and therefore can
+	 * move the instance around on the list at-will.
+	 */
+	if (unlikely(napi_disable_pending(n))) {
+		napi_complete(n);
+		goto out_unlock;
+	}
+
+	if (n->gro_list) {
+		/* flush too old packets
+		 * If HZ < 1000, flush all packets.
+		 */
+		napi_gro_flush(n, HZ >= 1000);
+	}
+
+	/* Some drivers may have called napi_schedule
+	 * prior to exhausting their budget.
+	 */
+	if (unlikely(!list_empty(&n->poll_list))) {
+		pr_warn_once("%s: Budget exhausted after napi rescheduled\n",
+			     n->dev ? n->dev->name : "backlog");
+		goto out_unlock;
+	}
+
+	list_add_tail(&n->poll_list, repoll);
+
+out_unlock:
+	netpoll_poll_unlock(have);
+
+	return work;
+}
+
+static void net_rx_action(struct softirq_action *h)
+{
+	struct softnet_data *sd = this_cpu_ptr(&softnet_data);
+	unsigned long time_limit = jiffies + 2;
+	int budget = netdev_budget;
+	LIST_HEAD(list);
+	LIST_HEAD(repoll);
+
+	local_irq_disable();
+	list_splice_init(&sd->poll_list, &list);
+	local_irq_enable();
+
+	for (;;) {
+		struct napi_struct *n;
+
+		if (list_empty(&list)) {
+			if (!sd_has_rps_ipi_waiting(sd) && list_empty(&repoll))
+				return;
+			break;
+		}
+
+		n = list_first_entry(&list, struct napi_struct, poll_list);
+		budget -= napi_poll(n, &repoll);
+
+		/* If softirq window is exhausted then punt.
+		 * Allow this to run for 2 jiffies since which will allow
+		 * an average latency of 1.5/HZ.
+		 */
+		if (unlikely(budget <= 0 ||
+			     time_after_eq(jiffies, time_limit))) {
+			sd->time_squeeze++;
+			break;
+		}
+	}
+
+	local_irq_disable();
+
+	list_splice_tail_init(&sd->poll_list, &list);
+	list_splice_tail(&repoll, &list);
+	list_splice(&list, &sd->poll_list);
+	if (!list_empty(&sd->poll_list))
+		__raise_softirq_irqoff(NET_RX_SOFTIRQ);
+
+	net_rps_action_and_irq_enable(sd);
+}
+
+struct netdev_adjacent {
+	struct net_device *dev;
+
+	/* upper master flag, there can only be one master device per list */
+	bool master;
+
+	/* counter for the number of times this device was added to us */
+	u16 ref_nr;
+
+	/* private field for the users */
+	void *private;
+
+	struct list_head list;
+	struct rcu_head rcu;
+};
+
+static struct netdev_adjacent *__netdev_find_adj(struct net_device *dev,
+						 struct net_device *adj_dev,
+						 struct list_head *adj_list)
+{
+	struct netdev_adjacent *adj;
+
+	list_for_each_entry(adj, adj_list, list) {
+		if (adj->dev == adj_dev)
+			return adj;
+	}
+	return NULL;
+}
+
+/**
+ * netdev_has_upper_dev - Check if device is linked to an upper device
+ * @dev: device
+ * @upper_dev: upper device to check
+ *
+ * Find out if a device is linked to specified upper device and return true
+ * in case it is. Note that this checks only immediate upper device,
+ * not through a complete stack of devices. The caller must hold the RTNL lock.
+ */
+bool netdev_has_upper_dev(struct net_device *dev,
+			  struct net_device *upper_dev)
+{
+	ASSERT_RTNL();
+
+	return __netdev_find_adj(dev, upper_dev, &dev->all_adj_list.upper);
+}
+EXPORT_SYMBOL(netdev_has_upper_dev);
+
+/**
+ * netdev_has_any_upper_dev - Check if device is linked to some device
+ * @dev: device
+ *
+ * Find out if a device is linked to an upper device and return true in case
+ * it is. The caller must hold the RTNL lock.
+ */
+static bool netdev_has_any_upper_dev(struct net_device *dev)
+{
+	ASSERT_RTNL();
+
+	return !list_empty(&dev->all_adj_list.upper);
+}
+
+/**
+ * netdev_master_upper_dev_get - Get master upper device
+ * @dev: device
+ *
+ * Find a master upper device and return pointer to it or NULL in case
+ * it's not there. The caller must hold the RTNL lock.
+ */
+struct net_device *netdev_master_upper_dev_get(struct net_device *dev)
+{
+	struct netdev_adjacent *upper;
+
+	ASSERT_RTNL();
+
+	if (list_empty(&dev->adj_list.upper))
+		return NULL;
+
+	upper = list_first_entry(&dev->adj_list.upper,
+				 struct netdev_adjacent, list);
+	if (likely(upper->master))
+		return upper->dev;
+	return NULL;
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_get);
+
+void *netdev_adjacent_get_private(struct list_head *adj_list)
+{
+	struct netdev_adjacent *adj;
+
+	adj = list_entry(adj_list, struct netdev_adjacent, list);
+
+	return adj->private;
+}
+EXPORT_SYMBOL(netdev_adjacent_get_private);
+
+/**
+ * netdev_upper_get_next_dev_rcu - Get the next dev from upper list
+ * @dev: device
+ * @iter: list_head ** of the current position
+ *
+ * Gets the next device from the dev's upper list, starting from iter
+ * position. The caller must hold RCU read lock.
+ */
+struct net_device *netdev_upper_get_next_dev_rcu(struct net_device *dev,
+						 struct list_head **iter)
+{
+	struct netdev_adjacent *upper;
+
+	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
+
+	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
+
+	if (&upper->list == &dev->adj_list.upper)
+		return NULL;
+
+	*iter = &upper->list;
+
+	return upper->dev;
+}
+EXPORT_SYMBOL(netdev_upper_get_next_dev_rcu);
+
+/**
+ * netdev_all_upper_get_next_dev_rcu - Get the next dev from upper list
+ * @dev: device
+ * @iter: list_head ** of the current position
+ *
+ * Gets the next device from the dev's upper list, starting from iter
+ * position. The caller must hold RCU read lock.
+ */
+struct net_device *netdev_all_upper_get_next_dev_rcu(struct net_device *dev,
+						     struct list_head **iter)
+{
+	struct netdev_adjacent *upper;
+
+	WARN_ON_ONCE(!rcu_read_lock_held() && !lockdep_rtnl_is_held());
+
+	upper = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
+
+	if (&upper->list == &dev->all_adj_list.upper)
+		return NULL;
+
+	*iter = &upper->list;
+
+	return upper->dev;
+}
+EXPORT_SYMBOL(netdev_all_upper_get_next_dev_rcu);
+
+/**
+ * netdev_lower_get_next_private - Get the next ->private from the
+ *				   lower neighbour list
+ * @dev: device
+ * @iter: list_head ** of the current position
+ *
+ * Gets the next netdev_adjacent->private from the dev's lower neighbour
+ * list, starting from iter position. The caller must hold either hold the
+ * RTNL lock or its own locking that guarantees that the neighbour lower
+ * list will remain unchainged.
+ */
+void *netdev_lower_get_next_private(struct net_device *dev,
+				    struct list_head **iter)
+{
+	struct netdev_adjacent *lower;
+
+	lower = list_entry(*iter, struct netdev_adjacent, list);
+
+	if (&lower->list == &dev->adj_list.lower)
+		return NULL;
+
+	*iter = lower->list.next;
+
+	return lower->private;
+}
+EXPORT_SYMBOL(netdev_lower_get_next_private);
+
+/**
+ * netdev_lower_get_next_private_rcu - Get the next ->private from the
+ *				       lower neighbour list, RCU
+ *				       variant
+ * @dev: device
+ * @iter: list_head ** of the current position
+ *
+ * Gets the next netdev_adjacent->private from the dev's lower neighbour
+ * list, starting from iter position. The caller must hold RCU read lock.
+ */
+void *netdev_lower_get_next_private_rcu(struct net_device *dev,
+					struct list_head **iter)
+{
+	struct netdev_adjacent *lower;
+
+	WARN_ON_ONCE(!rcu_read_lock_held());
+
+	lower = list_entry_rcu((*iter)->next, struct netdev_adjacent, list);
+
+	if (&lower->list == &dev->adj_list.lower)
+		return NULL;
+
+	*iter = &lower->list;
+
+	return lower->private;
+}
+EXPORT_SYMBOL(netdev_lower_get_next_private_rcu);
+
+/**
+ * netdev_lower_get_next - Get the next device from the lower neighbour
+ *                         list
+ * @dev: device
+ * @iter: list_head ** of the current position
+ *
+ * Gets the next netdev_adjacent from the dev's lower neighbour
+ * list, starting from iter position. The caller must hold RTNL lock or
+ * its own locking that guarantees that the neighbour lower
+ * list will remain unchainged.
+ */
+void *netdev_lower_get_next(struct net_device *dev, struct list_head **iter)
+{
+	struct netdev_adjacent *lower;
+
+	lower = list_entry((*iter)->next, struct netdev_adjacent, list);
+
+	if (&lower->list == &dev->adj_list.lower)
+		return NULL;
+
+	*iter = &lower->list;
+
+	return lower->dev;
+}
+EXPORT_SYMBOL(netdev_lower_get_next);
+
+/**
+ * netdev_lower_get_first_private_rcu - Get the first ->private from the
+ *				       lower neighbour list, RCU
+ *				       variant
+ * @dev: device
+ *
+ * Gets the first netdev_adjacent->private from the dev's lower neighbour
+ * list. The caller must hold RCU read lock.
+ */
+void *netdev_lower_get_first_private_rcu(struct net_device *dev)
+{
+	struct netdev_adjacent *lower;
+
+	lower = list_first_or_null_rcu(&dev->adj_list.lower,
+			struct netdev_adjacent, list);
+	if (lower)
+		return lower->private;
+	return NULL;
+}
+EXPORT_SYMBOL(netdev_lower_get_first_private_rcu);
+
+/**
+ * netdev_master_upper_dev_get_rcu - Get master upper device
+ * @dev: device
+ *
+ * Find a master upper device and return pointer to it or NULL in case
+ * it's not there. The caller must hold the RCU read lock.
+ */
+struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev)
+{
+	struct netdev_adjacent *upper;
+
+	upper = list_first_or_null_rcu(&dev->adj_list.upper,
+				       struct netdev_adjacent, list);
+	if (upper && likely(upper->master))
+		return upper->dev;
+	return NULL;
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu);
+
+static int netdev_adjacent_sysfs_add(struct net_device *dev,
+			      struct net_device *adj_dev,
+			      struct list_head *dev_list)
+{
+	char linkname[IFNAMSIZ+7];
+	sprintf(linkname, dev_list == &dev->adj_list.upper ?
+		"upper_%s" : "lower_%s", adj_dev->name);
+	return sysfs_create_link(&(dev->dev.kobj), &(adj_dev->dev.kobj),
+				 linkname);
+}
+static void netdev_adjacent_sysfs_del(struct net_device *dev,
+			       char *name,
+			       struct list_head *dev_list)
+{
+	char linkname[IFNAMSIZ+7];
+	sprintf(linkname, dev_list == &dev->adj_list.upper ?
+		"upper_%s" : "lower_%s", name);
+	sysfs_remove_link(&(dev->dev.kobj), linkname);
+}
+
+static inline bool netdev_adjacent_is_neigh_list(struct net_device *dev,
+						 struct net_device *adj_dev,
+						 struct list_head *dev_list)
+{
+	return (dev_list == &dev->adj_list.upper ||
+		dev_list == &dev->adj_list.lower) &&
+		net_eq(dev_net(dev), dev_net(adj_dev));
+}
+
+static int __netdev_adjacent_dev_insert(struct net_device *dev,
+					struct net_device *adj_dev,
+					struct list_head *dev_list,
+					void *private, bool master)
+{
+	struct netdev_adjacent *adj;
+	int ret;
+
+	adj = __netdev_find_adj(dev, adj_dev, dev_list);
+
+	if (adj) {
+		adj->ref_nr++;
+		return 0;
+	}
+
+	adj = kmalloc(sizeof(*adj), GFP_KERNEL);
+	if (!adj)
+		return -ENOMEM;
+
+	adj->dev = adj_dev;
+	adj->master = master;
+	adj->ref_nr = 1;
+	adj->private = private;
+	dev_hold(adj_dev);
+
+	pr_debug("dev_hold for %s, because of link added from %s to %s\n",
+		 adj_dev->name, dev->name, adj_dev->name);
+
+	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list)) {
+		ret = netdev_adjacent_sysfs_add(dev, adj_dev, dev_list);
+		if (ret)
+			goto free_adj;
+	}
+
+	/* Ensure that master link is always the first item in list. */
+	if (master) {
+		ret = sysfs_create_link(&(dev->dev.kobj),
+					&(adj_dev->dev.kobj), "master");
+		if (ret)
+			goto remove_symlinks;
+
+		list_add_rcu(&adj->list, dev_list);
+	} else {
+		list_add_tail_rcu(&adj->list, dev_list);
+	}
+
+	return 0;
+
+remove_symlinks:
+	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
+		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
+free_adj:
+	kfree(adj);
+	dev_put(adj_dev);
+
+	return ret;
+}
+
+static void __netdev_adjacent_dev_remove(struct net_device *dev,
+					 struct net_device *adj_dev,
+					 struct list_head *dev_list)
+{
+	struct netdev_adjacent *adj;
+
+	adj = __netdev_find_adj(dev, adj_dev, dev_list);
+
+	if (!adj) {
+		pr_err("tried to remove device %s from %s\n",
+		       dev->name, adj_dev->name);
+		BUG();
+	}
+
+	if (adj->ref_nr > 1) {
+		pr_debug("%s to %s ref_nr-- = %d\n", dev->name, adj_dev->name,
+			 adj->ref_nr-1);
+		adj->ref_nr--;
+		return;
+	}
+
+	if (adj->master)
+		sysfs_remove_link(&(dev->dev.kobj), "master");
+
+	if (netdev_adjacent_is_neigh_list(dev, adj_dev, dev_list))
+		netdev_adjacent_sysfs_del(dev, adj_dev->name, dev_list);
+
+	list_del_rcu(&adj->list);
+	pr_debug("dev_put for %s, because link removed from %s to %s\n",
+		 adj_dev->name, dev->name, adj_dev->name);
+	dev_put(adj_dev);
+	kfree_rcu(adj, rcu);
+}
+
+static int __netdev_adjacent_dev_link_lists(struct net_device *dev,
+					    struct net_device *upper_dev,
+					    struct list_head *up_list,
+					    struct list_head *down_list,
+					    void *private, bool master)
+{
+	int ret;
+
+	ret = __netdev_adjacent_dev_insert(dev, upper_dev, up_list, private,
+					   master);
+	if (ret)
+		return ret;
+
+	ret = __netdev_adjacent_dev_insert(upper_dev, dev, down_list, private,
+					   false);
+	if (ret) {
+		__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __netdev_adjacent_dev_link(struct net_device *dev,
+				      struct net_device *upper_dev)
+{
+	return __netdev_adjacent_dev_link_lists(dev, upper_dev,
+						&dev->all_adj_list.upper,
+						&upper_dev->all_adj_list.lower,
+						NULL, false);
+}
+
+static void __netdev_adjacent_dev_unlink_lists(struct net_device *dev,
+					       struct net_device *upper_dev,
+					       struct list_head *up_list,
+					       struct list_head *down_list)
+{
+	__netdev_adjacent_dev_remove(dev, upper_dev, up_list);
+	__netdev_adjacent_dev_remove(upper_dev, dev, down_list);
+}
+
+static void __netdev_adjacent_dev_unlink(struct net_device *dev,
+					 struct net_device *upper_dev)
+{
+	__netdev_adjacent_dev_unlink_lists(dev, upper_dev,
+					   &dev->all_adj_list.upper,
+					   &upper_dev->all_adj_list.lower);
+}
+
+static int __netdev_adjacent_dev_link_neighbour(struct net_device *dev,
+						struct net_device *upper_dev,
+						void *private, bool master)
+{
+	int ret = __netdev_adjacent_dev_link(dev, upper_dev);
+
+	if (ret)
+		return ret;
+
+	ret = __netdev_adjacent_dev_link_lists(dev, upper_dev,
+					       &dev->adj_list.upper,
+					       &upper_dev->adj_list.lower,
+					       private, master);
+	if (ret) {
+		__netdev_adjacent_dev_unlink(dev, upper_dev);
+		return ret;
+	}
+
+	return 0;
+}
+
+static void __netdev_adjacent_dev_unlink_neighbour(struct net_device *dev,
+						   struct net_device *upper_dev)
+{
+	__netdev_adjacent_dev_unlink(dev, upper_dev);
+	__netdev_adjacent_dev_unlink_lists(dev, upper_dev,
+					   &dev->adj_list.upper,
+					   &upper_dev->adj_list.lower);
+}
+
+static int __netdev_upper_dev_link(struct net_device *dev,
+				   struct net_device *upper_dev, bool master,
+				   void *private)
+{
+	struct netdev_adjacent *i, *j, *to_i, *to_j;
+	int ret = 0;
+
+	ASSERT_RTNL();
+
+	if (dev == upper_dev)
+		return -EBUSY;
+
+	/* To prevent loops, check if dev is not upper device to upper_dev. */
+	if (__netdev_find_adj(upper_dev, dev, &upper_dev->all_adj_list.upper))
+		return -EBUSY;
+
+	if (__netdev_find_adj(dev, upper_dev, &dev->adj_list.upper))
+		return -EEXIST;
+
+	if (master && netdev_master_upper_dev_get(dev))
+		return -EBUSY;
+
+	ret = __netdev_adjacent_dev_link_neighbour(dev, upper_dev, private,
+						   master);
+	if (ret)
+		return ret;
+
+	/* Now that we linked these devs, make all the upper_dev's
+	 * all_adj_list.upper visible to every dev's all_adj_list.lower an
+	 * versa, and don't forget the devices itself. All of these
+	 * links are non-neighbours.
+	 */
+	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
+		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
+			pr_debug("Interlinking %s with %s, non-neighbour\n",
+				 i->dev->name, j->dev->name);
+			ret = __netdev_adjacent_dev_link(i->dev, j->dev);
+			if (ret)
+				goto rollback_mesh;
+		}
+	}
+
+	/* add dev to every upper_dev's upper device */
+	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
+		pr_debug("linking %s's upper device %s with %s\n",
+			 upper_dev->name, i->dev->name, dev->name);
+		ret = __netdev_adjacent_dev_link(dev, i->dev);
+		if (ret)
+			goto rollback_upper_mesh;
+	}
+
+	/* add upper_dev to every dev's lower device */
+	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
+		pr_debug("linking %s's lower device %s with %s\n", dev->name,
+			 i->dev->name, upper_dev->name);
+		ret = __netdev_adjacent_dev_link(i->dev, upper_dev);
+		if (ret)
+			goto rollback_lower_mesh;
+	}
+
+	call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
+	return 0;
+
+rollback_lower_mesh:
+	to_i = i;
+	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
+		if (i == to_i)
+			break;
+		__netdev_adjacent_dev_unlink(i->dev, upper_dev);
+	}
+
+	i = NULL;
+
+rollback_upper_mesh:
+	to_i = i;
+	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list) {
+		if (i == to_i)
+			break;
+		__netdev_adjacent_dev_unlink(dev, i->dev);
+	}
+
+	i = j = NULL;
+
+rollback_mesh:
+	to_i = i;
+	to_j = j;
+	list_for_each_entry(i, &dev->all_adj_list.lower, list) {
+		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list) {
+			if (i == to_i && j == to_j)
+				break;
+			__netdev_adjacent_dev_unlink(i->dev, j->dev);
+		}
+		if (i == to_i)
+			break;
+	}
+
+	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
+
+	return ret;
+}
+
+/**
+ * netdev_upper_dev_link - Add a link to the upper device
+ * @dev: device
+ * @upper_dev: new upper device
+ *
+ * Adds a link to device which is upper to this one. The caller must hold
+ * the RTNL lock. On a failure a negative errno code is returned.
+ * On success the reference counts are adjusted and the function
+ * returns zero.
+ */
+int netdev_upper_dev_link(struct net_device *dev,
+			  struct net_device *upper_dev)
+{
+	return __netdev_upper_dev_link(dev, upper_dev, false, NULL);
+}
+EXPORT_SYMBOL(netdev_upper_dev_link);
+
+/**
+ * netdev_master_upper_dev_link - Add a master link to the upper device
+ * @dev: device
+ * @upper_dev: new upper device
+ *
+ * Adds a link to device which is upper to this one. In this case, only
+ * one master upper device can be linked, although other non-master devices
+ * might be linked as well. The caller must hold the RTNL lock.
+ * On a failure a negative errno code is returned. On success the reference
+ * counts are adjusted and the function returns zero.
+ */
+int netdev_master_upper_dev_link(struct net_device *dev,
+				 struct net_device *upper_dev)
+{
+	return __netdev_upper_dev_link(dev, upper_dev, true, NULL);
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_link);
+
+int netdev_master_upper_dev_link_private(struct net_device *dev,
+					 struct net_device *upper_dev,
+					 void *private)
+{
+	return __netdev_upper_dev_link(dev, upper_dev, true, private);
+}
+EXPORT_SYMBOL(netdev_master_upper_dev_link_private);
+
+/**
+ * netdev_upper_dev_unlink - Removes a link to upper device
+ * @dev: device
+ * @upper_dev: new upper device
+ *
+ * Removes a link to device which is upper to this one. The caller must hold
+ * the RTNL lock.
+ */
+void netdev_upper_dev_unlink(struct net_device *dev,
+			     struct net_device *upper_dev)
+{
+	struct netdev_adjacent *i, *j;
+	ASSERT_RTNL();
+
+	__netdev_adjacent_dev_unlink_neighbour(dev, upper_dev);
+
+	/* Here is the tricky part. We must remove all dev's lower
+	 * devices from all upper_dev's upper devices and vice
+	 * versa, to maintain the graph relationship.
+	 */
+	list_for_each_entry(i, &dev->all_adj_list.lower, list)
+		list_for_each_entry(j, &upper_dev->all_adj_list.upper, list)
+			__netdev_adjacent_dev_unlink(i->dev, j->dev);
+
+	/* remove also the devices itself from lower/upper device
+	 * list
+	 */
+	list_for_each_entry(i, &dev->all_adj_list.lower, list)
+		__netdev_adjacent_dev_unlink(i->dev, upper_dev);
+
+	list_for_each_entry(i, &upper_dev->all_adj_list.upper, list)
+		__netdev_adjacent_dev_unlink(dev, i->dev);
+
+	call_netdevice_notifiers(NETDEV_CHANGEUPPER, dev);
+}
+EXPORT_SYMBOL(netdev_upper_dev_unlink);
+
+/**
+ * netdev_bonding_info_change - Dispatch event about slave change
+ * @dev: device
+ * @bonding_info: info to dispatch
+ *
+ * Send NETDEV_BONDING_INFO to netdev notifiers with info.
+ * The caller must hold the RTNL lock.
+ */
+void netdev_bonding_info_change(struct net_device *dev,
+				struct netdev_bonding_info *bonding_info)
+{
+	struct netdev_notifier_bonding_info	info;
+
+	memcpy(&info.bonding_info, bonding_info,
+	       sizeof(struct netdev_bonding_info));
+	call_netdevice_notifiers_info(NETDEV_BONDING_INFO, dev,
+				      &info.info);
+}
+EXPORT_SYMBOL(netdev_bonding_info_change);
+
+static void netdev_adjacent_add_links(struct net_device *dev)
+{
+	struct netdev_adjacent *iter;
+
+	struct net *net = dev_net(dev);
+
+	list_for_each_entry(iter, &dev->adj_list.upper, list) {
+		if (!net_eq(net,dev_net(iter->dev)))
+			continue;
+		netdev_adjacent_sysfs_add(iter->dev, dev,
+					  &iter->dev->adj_list.lower);
+		netdev_adjacent_sysfs_add(dev, iter->dev,
+					  &dev->adj_list.upper);
+	}
+
+	list_for_each_entry(iter, &dev->adj_list.lower, list) {
+		if (!net_eq(net,dev_net(iter->dev)))
+			continue;
+		netdev_adjacent_sysfs_add(iter->dev, dev,
+					  &iter->dev->adj_list.upper);
+		netdev_adjacent_sysfs_add(dev, iter->dev,
+					  &dev->adj_list.lower);
+	}
+}
+
+static void netdev_adjacent_del_links(struct net_device *dev)
+{
+	struct netdev_adjacent *iter;
+
+	struct net *net = dev_net(dev);
+
+	list_for_each_entry(iter, &dev->adj_list.upper, list) {
+		if (!net_eq(net,dev_net(iter->dev)))
+			continue;
+		netdev_adjacent_sysfs_del(iter->dev, dev->name,
+					  &iter->dev->adj_list.lower);
+		netdev_adjacent_sysfs_del(dev, iter->dev->name,
+					  &dev->adj_list.upper);
+	}
+
+	list_for_each_entry(iter, &dev->adj_list.lower, list) {
+		if (!net_eq(net,dev_net(iter->dev)))
+			continue;
+		netdev_adjacent_sysfs_del(iter->dev, dev->name,
+					  &iter->dev->adj_list.upper);
+		netdev_adjacent_sysfs_del(dev, iter->dev->name,
+					  &dev->adj_list.lower);
+	}
+}
+
+void netdev_adjacent_rename_links(struct net_device *dev, char *oldname)
+{
+	struct netdev_adjacent *iter;
+
+	struct net *net = dev_net(dev);
+
+	list_for_each_entry(iter, &dev->adj_list.upper, list) {
+		if (!net_eq(net,dev_net(iter->dev)))
+			continue;
+		netdev_adjacent_sysfs_del(iter->dev, oldname,
+					  &iter->dev->adj_list.lower);
+		netdev_adjacent_sysfs_add(iter->dev, dev,
+					  &iter->dev->adj_list.lower);
+	}
+
+	list_for_each_entry(iter, &dev->adj_list.lower, list) {
+		if (!net_eq(net,dev_net(iter->dev)))
+			continue;
+		netdev_adjacent_sysfs_del(iter->dev, oldname,
+					  &iter->dev->adj_list.upper);
+		netdev_adjacent_sysfs_add(iter->dev, dev,
+					  &iter->dev->adj_list.upper);
+	}
+}
+
+void *netdev_lower_dev_get_private(struct net_device *dev,
+				   struct net_device *lower_dev)
+{
+	struct netdev_adjacent *lower;
+
+	if (!lower_dev)
+		return NULL;
+	lower = __netdev_find_adj(dev, lower_dev, &dev->adj_list.lower);
+	if (!lower)
+		return NULL;
+
+	return lower->private;
+}
+EXPORT_SYMBOL(netdev_lower_dev_get_private);
+
+
+int dev_get_nest_level(struct net_device *dev,
+		       bool (*type_check)(struct net_device *dev))
+{
+	struct net_device *lower = NULL;
+	struct list_head *iter;
+	int max_nest = -1;
+	int nest;
+
+	ASSERT_RTNL();
+
+	netdev_for_each_lower_dev(dev, lower, iter) {
+		nest = dev_get_nest_level(lower, type_check);
+		if (max_nest < nest)
+			max_nest = nest;
+	}
+
+	if (type_check(dev))
+		max_nest++;
+
+	return max_nest;
+}
+EXPORT_SYMBOL(dev_get_nest_level);
+
+static void dev_change_rx_flags(struct net_device *dev, int flags)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+
+	if (ops->ndo_change_rx_flags)
+		ops->ndo_change_rx_flags(dev, flags);
+}
+
+static int __dev_set_promiscuity(struct net_device *dev, int inc, bool notify)
+{
+	unsigned int old_flags = dev->flags;
+	kuid_t uid;
+	kgid_t gid;
+
+	ASSERT_RTNL();
+
+	dev->flags |= IFF_PROMISC;
+	dev->promiscuity += inc;
+	if (dev->promiscuity == 0) {
+		/*
+		 * Avoid overflow.
+		 * If inc causes overflow, untouch promisc and return error.
+		 */
+		if (inc < 0)
+			dev->flags &= ~IFF_PROMISC;
+		else {
+			dev->promiscuity -= inc;
+			pr_warn("%s: promiscuity touches roof, set promiscuity failed. promiscuity feature of device might be broken.\n",
+				dev->name);
+			return -EOVERFLOW;
+		}
+	}
+	if (dev->flags != old_flags) {
+		pr_info("device %s %s promiscuous mode\n",
+			dev->name,
+			dev->flags & IFF_PROMISC ? "entered" : "left");
+		if (audit_enabled) {
+			current_uid_gid(&uid, &gid);
+			audit_log(current->audit_context, GFP_ATOMIC,
+				AUDIT_ANOM_PROMISCUOUS,
+				"dev=%s prom=%d old_prom=%d auid=%u uid=%u gid=%u ses=%u",
+				dev->name, (dev->flags & IFF_PROMISC),
+				(old_flags & IFF_PROMISC),
+				from_kuid(&init_user_ns, audit_get_loginuid(current)),
+				from_kuid(&init_user_ns, uid),
+				from_kgid(&init_user_ns, gid),
+				audit_get_sessionid(current));
+		}
+
+		dev_change_rx_flags(dev, IFF_PROMISC);
+	}
+	if (notify)
+		__dev_notify_flags(dev, old_flags, IFF_PROMISC);
+	return 0;
+}
+
+/**
+ *	dev_set_promiscuity	- update promiscuity count on a device
+ *	@dev: device
+ *	@inc: modifier
+ *
+ *	Add or remove promiscuity from a device. While the count in the device
+ *	remains above zero the interface remains promiscuous. Once it hits zero
+ *	the device reverts back to normal filtering operation. A negative inc
+ *	value is used to drop promiscuity on the device.
+ *	Return 0 if successful or a negative errno code on error.
+ */
+int dev_set_promiscuity(struct net_device *dev, int inc)
+{
+	unsigned int old_flags = dev->flags;
+	int err;
+
+	err = __dev_set_promiscuity(dev, inc, true);
+	if (err < 0)
+		return err;
+	if (dev->flags != old_flags)
+		dev_set_rx_mode(dev);
+	return err;
+}
+EXPORT_SYMBOL(dev_set_promiscuity);
+
+static int __dev_set_allmulti(struct net_device *dev, int inc, bool notify)
+{
+	unsigned int old_flags = dev->flags, old_gflags = dev->gflags;
+
+	ASSERT_RTNL();
+
+	dev->flags |= IFF_ALLMULTI;
+	dev->allmulti += inc;
+	if (dev->allmulti == 0) {
+		/*
+		 * Avoid overflow.
+		 * If inc causes overflow, untouch allmulti and return error.
+		 */
+		if (inc < 0)
+			dev->flags &= ~IFF_ALLMULTI;
+		else {
+			dev->allmulti -= inc;
+			pr_warn("%s: allmulti touches roof, set allmulti failed. allmulti feature of device might be broken.\n",
+				dev->name);
+			return -EOVERFLOW;
+		}
+	}
+	if (dev->flags ^ old_flags) {
+		dev_change_rx_flags(dev, IFF_ALLMULTI);
+		dev_set_rx_mode(dev);
+		if (notify)
+			__dev_notify_flags(dev, old_flags,
+					   dev->gflags ^ old_gflags);
+	}
+	return 0;
+}
+
+/**
+ *	dev_set_allmulti	- update allmulti count on a device
+ *	@dev: device
+ *	@inc: modifier
+ *
+ *	Add or remove reception of all multicast frames to a device. While the
+ *	count in the device remains above zero the interface remains listening
+ *	to all interfaces. Once it hits zero the device reverts back to normal
+ *	filtering operation. A negative @inc value is used to drop the counter
+ *	when releasing a resource needing all multicasts.
+ *	Return 0 if successful or a negative errno code on error.
+ */
+
+int dev_set_allmulti(struct net_device *dev, int inc)
+{
+	return __dev_set_allmulti(dev, inc, true);
+}
+EXPORT_SYMBOL(dev_set_allmulti);
+
+/*
+ *	Upload unicast and multicast address lists to device and
+ *	configure RX filtering. When the device doesn't support unicast
+ *	filtering it is put in promiscuous mode while unicast addresses
+ *	are present.
+ */
+void __dev_set_rx_mode(struct net_device *dev)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+
+	/* dev_open will call this function so the list will stay sane. */
+	if (!(dev->flags&IFF_UP))
+		return;
+
+	if (!netif_device_present(dev))
+		return;
+
+	if (!(dev->priv_flags & IFF_UNICAST_FLT)) {
+		/* Unicast addresses changes may only happen under the rtnl,
+		 * therefore calling __dev_set_promiscuity here is safe.
+		 */
+		if (!netdev_uc_empty(dev) && !dev->uc_promisc) {
+			__dev_set_promiscuity(dev, 1, false);
+			dev->uc_promisc = true;
+		} else if (netdev_uc_empty(dev) && dev->uc_promisc) {
+			__dev_set_promiscuity(dev, -1, false);
+			dev->uc_promisc = false;
+		}
+	}
+
+	if (ops->ndo_set_rx_mode)
+		ops->ndo_set_rx_mode(dev);
+}
+
+void dev_set_rx_mode(struct net_device *dev)
+{
+	netif_addr_lock_bh(dev);
+	__dev_set_rx_mode(dev);
+	netif_addr_unlock_bh(dev);
+}
+
+/**
+ *	dev_get_flags - get flags reported to userspace
+ *	@dev: device
+ *
+ *	Get the combination of flag bits exported through APIs to userspace.
+ */
+unsigned int dev_get_flags(const struct net_device *dev)
+{
+	unsigned int flags;
+
+	flags = (dev->flags & ~(IFF_PROMISC |
+				IFF_ALLMULTI |
+				IFF_RUNNING |
+				IFF_LOWER_UP |
+				IFF_DORMANT)) |
+		(dev->gflags & (IFF_PROMISC |
+				IFF_ALLMULTI));
+
+	if (netif_running(dev)) {
+		if (netif_oper_up(dev))
+			flags |= IFF_RUNNING;
+		if (netif_carrier_ok(dev))
+			flags |= IFF_LOWER_UP;
+		if (netif_dormant(dev))
+			flags |= IFF_DORMANT;
+	}
+
+	return flags;
+}
+EXPORT_SYMBOL(dev_get_flags);
+
+int __dev_change_flags(struct net_device *dev, unsigned int flags)
+{
+	unsigned int old_flags = dev->flags;
+	int ret;
+
+	ASSERT_RTNL();
+
+	/*
+	 *	Set the flags on our device.
+	 */
+
+	dev->flags = (flags & (IFF_DEBUG | IFF_NOTRAILERS | IFF_NOARP |
+			       IFF_DYNAMIC | IFF_MULTICAST | IFF_PORTSEL |
+			       IFF_AUTOMEDIA)) |
+		     (dev->flags & (IFF_UP | IFF_VOLATILE | IFF_PROMISC |
+				    IFF_ALLMULTI));
+
+	/*
+	 *	Load in the correct multicast list now the flags have changed.
+	 */
+
+	if ((old_flags ^ flags) & IFF_MULTICAST)
+		dev_change_rx_flags(dev, IFF_MULTICAST);
+
+	dev_set_rx_mode(dev);
+
+	/*
+	 *	Have we downed the interface. We handle IFF_UP ourselves
+	 *	according to user attempts to set it, rather than blindly
+	 *	setting it.
+	 */
+
+	ret = 0;
+	if ((old_flags ^ flags) & IFF_UP)
+		ret = ((old_flags & IFF_UP) ? __dev_close : __dev_open)(dev);
+
+	if ((flags ^ dev->gflags) & IFF_PROMISC) {
+		int inc = (flags & IFF_PROMISC) ? 1 : -1;
+		unsigned int old_flags = dev->flags;
+
+		dev->gflags ^= IFF_PROMISC;
+
+		if (__dev_set_promiscuity(dev, inc, false) >= 0)
+			if (dev->flags != old_flags)
+				dev_set_rx_mode(dev);
+	}
+
+	/* NOTE: order of synchronization of IFF_PROMISC and IFF_ALLMULTI
+	   is important. Some (broken) drivers set IFF_PROMISC, when
+	   IFF_ALLMULTI is requested not asking us and not reporting.
+	 */
+	if ((flags ^ dev->gflags) & IFF_ALLMULTI) {
+		int inc = (flags & IFF_ALLMULTI) ? 1 : -1;
+
+		dev->gflags ^= IFF_ALLMULTI;
+		__dev_set_allmulti(dev, inc, false);
+	}
+
+	return ret;
+}
+
+void __dev_notify_flags(struct net_device *dev, unsigned int old_flags,
+			unsigned int gchanges)
+{
+	unsigned int changes = dev->flags ^ old_flags;
+
+	if (gchanges)
+		rtmsg_ifinfo(RTM_NEWLINK, dev, gchanges, GFP_ATOMIC);
+
+	if (changes & IFF_UP) {
+		if (dev->flags & IFF_UP)
+			call_netdevice_notifiers(NETDEV_UP, dev);
+		else
+			call_netdevice_notifiers(NETDEV_DOWN, dev);
+	}
+
+	if (dev->flags & IFF_UP &&
+	    (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) {
+		struct netdev_notifier_change_info change_info;
+
+		change_info.flags_changed = changes;
+		call_netdevice_notifiers_info(NETDEV_CHANGE, dev,
+					      &change_info.info);
+	}
+}
+
+/**
+ *	dev_change_flags - change device settings
+ *	@dev: device
+ *	@flags: device state flags
+ *
+ *	Change settings on device based state flags. The flags are
+ *	in the userspace exported format.
+ */
+int dev_change_flags(struct net_device *dev, unsigned int flags)
+{
+	int ret;
+	unsigned int changes, old_flags = dev->flags, old_gflags = dev->gflags;
+
+	ret = __dev_change_flags(dev, flags);
+	if (ret < 0)
+		return ret;
+
+	changes = (old_flags ^ dev->flags) | (old_gflags ^ dev->gflags);
+	__dev_notify_flags(dev, old_flags, changes);
+	return ret;
+}
+EXPORT_SYMBOL(dev_change_flags);
+
+static int __dev_set_mtu(struct net_device *dev, int new_mtu)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+
+	if (ops->ndo_change_mtu)
+		return ops->ndo_change_mtu(dev, new_mtu);
+
+	dev->mtu = new_mtu;
+	return 0;
+}
+
+/**
+ *	dev_set_mtu - Change maximum transfer unit
+ *	@dev: device
+ *	@new_mtu: new transfer unit
+ *
+ *	Change the maximum transfer size of the network device.
+ */
+int dev_set_mtu(struct net_device *dev, int new_mtu)
+{
+	int err, orig_mtu;
+
+	if (new_mtu == dev->mtu)
+		return 0;
+
+	/*	MTU must be positive.	 */
+	if (new_mtu < 0)
+		return -EINVAL;
+
+	if (!netif_device_present(dev))
+		return -ENODEV;
+
+	err = call_netdevice_notifiers(NETDEV_PRECHANGEMTU, dev);
+	err = notifier_to_errno(err);
+	if (err)
+		return err;
+
+	orig_mtu = dev->mtu;
+	err = __dev_set_mtu(dev, new_mtu);
+
+	if (!err) {
+		err = call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
+		err = notifier_to_errno(err);
+		if (err) {
+			/* setting mtu back and notifying everyone again,
+			 * so that they have a chance to revert changes.
+			 */
+			__dev_set_mtu(dev, orig_mtu);
+			call_netdevice_notifiers(NETDEV_CHANGEMTU, dev);
+		}
+	}
+	return err;
+}
+EXPORT_SYMBOL(dev_set_mtu);
+
+/**
+ *	dev_set_group - Change group this device belongs to
+ *	@dev: device
+ *	@new_group: group this device should belong to
+ */
+void dev_set_group(struct net_device *dev, int new_group)
+{
+	dev->group = new_group;
+}
+EXPORT_SYMBOL(dev_set_group);
+
+/**
+ *	dev_set_mac_address - Change Media Access Control Address
+ *	@dev: device
+ *	@sa: new address
+ *
+ *	Change the hardware (MAC) address of the device
+ */
+int dev_set_mac_address(struct net_device *dev, struct sockaddr *sa)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+	int err;
+
+	if (!ops->ndo_set_mac_address)
+		return -EOPNOTSUPP;
+	if (sa->sa_family != dev->type)
+		return -EINVAL;
+	if (!netif_device_present(dev))
+		return -ENODEV;
+	err = ops->ndo_set_mac_address(dev, sa);
+	if (err)
+		return err;
+	dev->addr_assign_type = NET_ADDR_SET;
+	call_netdevice_notifiers(NETDEV_CHANGEADDR, dev);
+	add_device_randomness(dev->dev_addr, dev->addr_len);
+	return 0;
+}
+EXPORT_SYMBOL(dev_set_mac_address);
+
+/**
+ *	dev_change_carrier - Change device carrier
+ *	@dev: device
+ *	@new_carrier: new value
+ *
+ *	Change device carrier
+ */
+int dev_change_carrier(struct net_device *dev, bool new_carrier)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+
+	if (!ops->ndo_change_carrier)
+		return -EOPNOTSUPP;
+	if (!netif_device_present(dev))
+		return -ENODEV;
+	return ops->ndo_change_carrier(dev, new_carrier);
+}
+EXPORT_SYMBOL(dev_change_carrier);
+
+/**
+ *	dev_get_phys_port_id - Get device physical port ID
+ *	@dev: device
+ *	@ppid: port ID
+ *
+ *	Get device physical port ID
+ */
+int dev_get_phys_port_id(struct net_device *dev,
+			 struct netdev_phys_item_id *ppid)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+
+	if (!ops->ndo_get_phys_port_id)
+		return -EOPNOTSUPP;
+	return ops->ndo_get_phys_port_id(dev, ppid);
+}
+EXPORT_SYMBOL(dev_get_phys_port_id);
+
+/**
+ *	dev_get_phys_port_name - Get device physical port name
+ *	@dev: device
+ *	@name: port name
+ *
+ *	Get device physical port name
+ */
+int dev_get_phys_port_name(struct net_device *dev,
+			   char *name, size_t len)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+
+	if (!ops->ndo_get_phys_port_name)
+		return -EOPNOTSUPP;
+	return ops->ndo_get_phys_port_name(dev, name, len);
+}
+EXPORT_SYMBOL(dev_get_phys_port_name);
+
+/**
+ *	dev_new_index	-	allocate an ifindex
+ *	@net: the applicable net namespace
+ *
+ *	Returns a suitable unique value for a new device interface
+ *	number.  The caller must hold the rtnl semaphore or the
+ *	dev_base_lock to be sure it remains unique.
+ */
+static int dev_new_index(struct net *net)
+{
+	int ifindex = net->ifindex;
+	for (;;) {
+		if (++ifindex <= 0)
+			ifindex = 1;
+		if (!__dev_get_by_index(net, ifindex))
+			return net->ifindex = ifindex;
+	}
+}
+
+/* Delayed registration/unregisteration */
+static LIST_HEAD(net_todo_list);
+DECLARE_WAIT_QUEUE_HEAD(netdev_unregistering_wq);
+
+static void net_set_todo(struct net_device *dev)
+{
+	list_add_tail(&dev->todo_list, &net_todo_list);
+	dev_net(dev)->dev_unreg_count++;
+}
+
+static void rollback_registered_many(struct list_head *head)
+{
+	struct net_device *dev, *tmp;
+	LIST_HEAD(close_head);
+
+	BUG_ON(dev_boot_phase);
+	ASSERT_RTNL();
+
+	list_for_each_entry_safe(dev, tmp, head, unreg_list) {
+		/* Some devices call without registering
+		 * for initialization unwind. Remove those
+		 * devices and proceed with the remaining.
+		 */
+		if (dev->reg_state == NETREG_UNINITIALIZED) {
+			pr_debug("unregister_netdevice: device %s/%p never was registered\n",
+				 dev->name, dev);
+
+			WARN_ON(1);
+			list_del(&dev->unreg_list);
+			continue;
+		}
+		dev->dismantle = true;
+		BUG_ON(dev->reg_state != NETREG_REGISTERED);
+	}
+
+	/* If device is running, close it first. */
+	list_for_each_entry(dev, head, unreg_list)
+		list_add_tail(&dev->close_list, &close_head);
+	dev_close_many(&close_head, true);
+
+	list_for_each_entry(dev, head, unreg_list) {
+		/* And unlink it from device chain. */
+		unlist_netdevice(dev);
+
+		dev->reg_state = NETREG_UNREGISTERING;
+	}
+
+	synchronize_net();
+
+	list_for_each_entry(dev, head, unreg_list) {
+		struct sk_buff *skb = NULL;
+
+		/* Shutdown queueing discipline. */
+		dev_shutdown(dev);
+
+
+		/* Notify protocols, that we are about to destroy
+		   this device. They should clean all the things.
+		*/
+		call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
+
+		if (!dev->rtnl_link_ops ||
+		    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
+			skb = rtmsg_ifinfo_build_skb(RTM_DELLINK, dev, ~0U,
+						     GFP_KERNEL);
+
+		/*
+		 *	Flush the unicast and multicast chains
+		 */
+		dev_uc_flush(dev);
+		dev_mc_flush(dev);
+
+		if (dev->netdev_ops->ndo_uninit)
+			dev->netdev_ops->ndo_uninit(dev);
+
+		if (skb)
+			rtmsg_ifinfo_send(skb, dev, GFP_KERNEL);
+
+		/* Notifier chain MUST detach us all upper devices. */
+		WARN_ON(netdev_has_any_upper_dev(dev));
+
+		/* Remove entries from kobject tree */
+		netdev_unregister_kobject(dev);
+#ifdef CONFIG_XPS
+		/* Remove XPS queueing entries */
+		netif_reset_xps_queues_gt(dev, 0);
+#endif
+	}
+
+	synchronize_net();
+
+	list_for_each_entry(dev, head, unreg_list)
+		dev_put(dev);
+}
+
+static void rollback_registered(struct net_device *dev)
+{
+	LIST_HEAD(single);
+
+	list_add(&dev->unreg_list, &single);
+	rollback_registered_many(&single);
+	list_del(&single);
+}
+
+static netdev_features_t netdev_fix_features(struct net_device *dev,
+	netdev_features_t features)
+{
+	/* Fix illegal checksum combinations */
+	if ((features & NETIF_F_HW_CSUM) &&
+	    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
+		netdev_warn(dev, "mixed HW and IP checksum settings.\n");
+		features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
+	}
+
+	/* TSO requires that SG is present as well. */
+	if ((features & NETIF_F_ALL_TSO) && !(features & NETIF_F_SG)) {
+		netdev_dbg(dev, "Dropping TSO features since no SG feature.\n");
+		features &= ~NETIF_F_ALL_TSO;
+	}
+
+	if ((features & NETIF_F_TSO) && !(features & NETIF_F_HW_CSUM) &&
+					!(features & NETIF_F_IP_CSUM)) {
+		netdev_dbg(dev, "Dropping TSO features since no CSUM feature.\n");
+		features &= ~NETIF_F_TSO;
+		features &= ~NETIF_F_TSO_ECN;
+	}
+
+	if ((features & NETIF_F_TSO6) && !(features & NETIF_F_HW_CSUM) &&
+					 !(features & NETIF_F_IPV6_CSUM)) {
+		netdev_dbg(dev, "Dropping TSO6 features since no CSUM feature.\n");
+		features &= ~NETIF_F_TSO6;
+	}
+
+	/* TSO ECN requires that TSO is present as well. */
+	if ((features & NETIF_F_ALL_TSO) == NETIF_F_TSO_ECN)
+		features &= ~NETIF_F_TSO_ECN;
+
+	/* Software GSO depends on SG. */
+	if ((features & NETIF_F_GSO) && !(features & NETIF_F_SG)) {
+		netdev_dbg(dev, "Dropping NETIF_F_GSO since no SG feature.\n");
+		features &= ~NETIF_F_GSO;
+	}
+
+	/* UFO needs SG and checksumming */
+	if (features & NETIF_F_UFO) {
+		/* maybe split UFO into V4 and V6? */
+		if (!((features & NETIF_F_GEN_CSUM) ||
+		    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
+			    == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
+			netdev_dbg(dev,
+				"Dropping NETIF_F_UFO since no checksum offload features.\n");
+			features &= ~NETIF_F_UFO;
+		}
+
+		if (!(features & NETIF_F_SG)) {
+			netdev_dbg(dev,
+				"Dropping NETIF_F_UFO since no NETIF_F_SG feature.\n");
+			features &= ~NETIF_F_UFO;
+		}
+	}
+
+#ifdef CONFIG_NET_RX_BUSY_POLL
+	if (dev->netdev_ops->ndo_busy_poll)
+		features |= NETIF_F_BUSY_POLL;
+	else
+#endif
+		features &= ~NETIF_F_BUSY_POLL;
+
+	return features;
+}
+
+int __netdev_update_features(struct net_device *dev)
+{
+	netdev_features_t features;
+	int err = 0;
+
+	ASSERT_RTNL();
+
+	features = netdev_get_wanted_features(dev);
+
+	if (dev->netdev_ops->ndo_fix_features)
+		features = dev->netdev_ops->ndo_fix_features(dev, features);
+
+	/* driver might be less strict about feature dependencies */
+	features = netdev_fix_features(dev, features);
+
+	if (dev->features == features)
+		return 0;
+
+	netdev_dbg(dev, "Features changed: %pNF -> %pNF\n",
+		&dev->features, &features);
+
+	if (dev->netdev_ops->ndo_set_features)
+		err = dev->netdev_ops->ndo_set_features(dev, features);
+
+	if (unlikely(err < 0)) {
+		netdev_err(dev,
+			"set_features() failed (%d); wanted %pNF, left %pNF\n",
+			err, &features, &dev->features);
+		return -1;
+	}
+
+	if (!err)
+		dev->features = features;
+
+	return 1;
+}
+
+/**
+ *	netdev_update_features - recalculate device features
+ *	@dev: the device to check
+ *
+ *	Recalculate dev->features set and send notifications if it
+ *	has changed. Should be called after driver or hardware dependent
+ *	conditions might have changed that influence the features.
+ */
+void netdev_update_features(struct net_device *dev)
+{
+	if (__netdev_update_features(dev))
+		netdev_features_change(dev);
+}
+EXPORT_SYMBOL(netdev_update_features);
+
+/**
+ *	netdev_change_features - recalculate device features
+ *	@dev: the device to check
+ *
+ *	Recalculate dev->features set and send notifications even
+ *	if they have not changed. Should be called instead of
+ *	netdev_update_features() if also dev->vlan_features might
+ *	have changed to allow the changes to be propagated to stacked
+ *	VLAN devices.
+ */
+void netdev_change_features(struct net_device *dev)
+{
+	__netdev_update_features(dev);
+	netdev_features_change(dev);
+}
+EXPORT_SYMBOL(netdev_change_features);
+
+/**
+ *	netif_stacked_transfer_operstate -	transfer operstate
+ *	@rootdev: the root or lower level device to transfer state from
+ *	@dev: the device to transfer operstate to
+ *
+ *	Transfer operational state from root to device. This is normally
+ *	called when a stacking relationship exists between the root
+ *	device and the device(a leaf device).
+ */
+void netif_stacked_transfer_operstate(const struct net_device *rootdev,
+					struct net_device *dev)
+{
+	if (rootdev->operstate == IF_OPER_DORMANT)
+		netif_dormant_on(dev);
+	else
+		netif_dormant_off(dev);
+
+	if (netif_carrier_ok(rootdev)) {
+		if (!netif_carrier_ok(dev))
+			netif_carrier_on(dev);
+	} else {
+		if (netif_carrier_ok(dev))
+			netif_carrier_off(dev);
+	}
+}
+EXPORT_SYMBOL(netif_stacked_transfer_operstate);
+
+#ifdef CONFIG_SYSFS
+static int netif_alloc_rx_queues(struct net_device *dev)
+{
+	unsigned int i, count = dev->num_rx_queues;
+	struct netdev_rx_queue *rx;
+	size_t sz = count * sizeof(*rx);
+
+	BUG_ON(count < 1);
+
+	rx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
+	if (!rx) {
+		rx = vzalloc(sz);
+		if (!rx)
+			return -ENOMEM;
+	}
+	dev->_rx = rx;
+
+	for (i = 0; i < count; i++)
+		rx[i].dev = dev;
+	return 0;
+}
+#endif
+
+static void netdev_init_one_queue(struct net_device *dev,
+				  struct netdev_queue *queue, void *_unused)
+{
+	/* Initialize queue lock */
+	spin_lock_init(&queue->_xmit_lock);
+	netdev_set_xmit_lockdep_class(&queue->_xmit_lock, dev->type);
+	queue->xmit_lock_owner = -1;
+	netdev_queue_numa_node_write(queue, NUMA_NO_NODE);
+	queue->dev = dev;
+#ifdef CONFIG_BQL
+	dql_init(&queue->dql, HZ);
+#endif
+}
+
+static void netif_free_tx_queues(struct net_device *dev)
+{
+	kvfree(dev->_tx);
+}
+
+static int netif_alloc_netdev_queues(struct net_device *dev)
+{
+	unsigned int count = dev->num_tx_queues;
+	struct netdev_queue *tx;
+	size_t sz = count * sizeof(*tx);
+
+	BUG_ON(count < 1 || count > 0xffff);
+
+	tx = kzalloc(sz, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
+	if (!tx) {
+		tx = vzalloc(sz);
+		if (!tx)
+			return -ENOMEM;
+	}
+	dev->_tx = tx;
+
+	netdev_for_each_tx_queue(dev, netdev_init_one_queue, NULL);
+	spin_lock_init(&dev->tx_global_lock);
+
+	return 0;
+}
+
+/**
+ *	register_netdevice	- register a network device
+ *	@dev: device to register
+ *
+ *	Take a completed network device structure and add it to the kernel
+ *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
+ *	chain. 0 is returned on success. A negative errno code is returned
+ *	on a failure to set up the device, or if the name is a duplicate.
+ *
+ *	Callers must hold the rtnl semaphore. You may want
+ *	register_netdev() instead of this.
+ *
+ *	BUGS:
+ *	The locking appears insufficient to guarantee two parallel registers
+ *	will not get the same name.
+ */
+
+int register_netdevice(struct net_device *dev)
+{
+	int ret;
+	struct net *net = dev_net(dev);
+
+	BUG_ON(dev_boot_phase);
+	ASSERT_RTNL();
+
+	might_sleep();
+
+	/* When net_device's are persistent, this will be fatal. */
+	BUG_ON(dev->reg_state != NETREG_UNINITIALIZED);
+	BUG_ON(!net);
+
+	spin_lock_init(&dev->addr_list_lock);
+	netdev_set_addr_lockdep_class(dev);
+
+	ret = dev_get_valid_name(net, dev, dev->name);
+	if (ret < 0)
+		goto out;
+
+	/* Init, if this function is available */
+	if (dev->netdev_ops->ndo_init) {
+		ret = dev->netdev_ops->ndo_init(dev);
+		if (ret) {
+			if (ret > 0)
+				ret = -EIO;
+			goto out;
+		}
+	}
+
+	if (((dev->hw_features | dev->features) &
+	     NETIF_F_HW_VLAN_CTAG_FILTER) &&
+	    (!dev->netdev_ops->ndo_vlan_rx_add_vid ||
+	     !dev->netdev_ops->ndo_vlan_rx_kill_vid)) {
+		netdev_WARN(dev, "Buggy VLAN acceleration in driver!\n");
+		ret = -EINVAL;
+		goto err_uninit;
+	}
+
+	ret = -EBUSY;
+	if (!dev->ifindex)
+		dev->ifindex = dev_new_index(net);
+	else if (__dev_get_by_index(net, dev->ifindex))
+		goto err_uninit;
+
+	/* Transfer changeable features to wanted_features and enable
+	 * software offloads (GSO and GRO).
+	 */
+	dev->hw_features |= NETIF_F_SOFT_FEATURES;
+	dev->features |= NETIF_F_SOFT_FEATURES;
+	dev->wanted_features = dev->features & dev->hw_features;
+
+	if (!(dev->flags & IFF_LOOPBACK)) {
+		dev->hw_features |= NETIF_F_NOCACHE_COPY;
+	}
+
+	/* Make NETIF_F_HIGHDMA inheritable to VLAN devices.
+	 */
+	dev->vlan_features |= NETIF_F_HIGHDMA;
+
+	/* Make NETIF_F_SG inheritable to tunnel devices.
+	 */
+	dev->hw_enc_features |= NETIF_F_SG;
+
+	/* Make NETIF_F_SG inheritable to MPLS.
+	 */
+	dev->mpls_features |= NETIF_F_SG;
+
+	ret = call_netdevice_notifiers(NETDEV_POST_INIT, dev);
+	ret = notifier_to_errno(ret);
+	if (ret)
+		goto err_uninit;
+
+	ret = netdev_register_kobject(dev);
+	if (ret)
+		goto err_uninit;
+	dev->reg_state = NETREG_REGISTERED;
+
+	__netdev_update_features(dev);
+
+	/*
+	 *	Default initial state at registry is that the
+	 *	device is present.
+	 */
+
+	set_bit(__LINK_STATE_PRESENT, &dev->state);
+
+	linkwatch_init_dev(dev);
+
+	dev_init_scheduler(dev);
+	dev_hold(dev);
+	list_netdevice(dev);
+	add_device_randomness(dev->dev_addr, dev->addr_len);
+
+	/* If the device has permanent device address, driver should
+	 * set dev_addr and also addr_assign_type should be set to
+	 * NET_ADDR_PERM (default value).
+	 */
+	if (dev->addr_assign_type == NET_ADDR_PERM)
+		memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len);
+
+	/* Notify protocols, that a new device appeared. */
+	ret = call_netdevice_notifiers(NETDEV_REGISTER, dev);
+	ret = notifier_to_errno(ret);
+	if (ret) {
+		rollback_registered(dev);
+		dev->reg_state = NETREG_UNREGISTERED;
+	}
+	/*
+	 *	Prevent userspace races by waiting until the network
+	 *	device is fully setup before sending notifications.
+	 */
+	if (!dev->rtnl_link_ops ||
+	    dev->rtnl_link_state == RTNL_LINK_INITIALIZED)
+		rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
+
+out:
+	return ret;
+
+err_uninit:
+	if (dev->netdev_ops->ndo_uninit)
+		dev->netdev_ops->ndo_uninit(dev);
+	goto out;
+}
+EXPORT_SYMBOL(register_netdevice);
+
+/**
+ *	init_dummy_netdev	- init a dummy network device for NAPI
+ *	@dev: device to init
+ *
+ *	This takes a network device structure and initialize the minimum
+ *	amount of fields so it can be used to schedule NAPI polls without
+ *	registering a full blown interface. This is to be used by drivers
+ *	that need to tie several hardware interfaces to a single NAPI
+ *	poll scheduler due to HW limitations.
+ */
+int init_dummy_netdev(struct net_device *dev)
+{
+	/* Clear everything. Note we don't initialize spinlocks
+	 * are they aren't supposed to be taken by any of the
+	 * NAPI code and this dummy netdev is supposed to be
+	 * only ever used for NAPI polls
+	 */
+	memset(dev, 0, sizeof(struct net_device));
+
+	/* make sure we BUG if trying to hit standard
+	 * register/unregister code path
+	 */
+	dev->reg_state = NETREG_DUMMY;
+
+	/* NAPI wants this */
+	INIT_LIST_HEAD(&dev->napi_list);
+
+	/* a dummy interface is started by default */
+	set_bit(__LINK_STATE_PRESENT, &dev->state);
+	set_bit(__LINK_STATE_START, &dev->state);
+
+	/* Note : We dont allocate pcpu_refcnt for dummy devices,
+	 * because users of this 'device' dont need to change
+	 * its refcount.
+	 */
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(init_dummy_netdev);
+
+
+/**
+ *	register_netdev	- register a network device
+ *	@dev: device to register
+ *
+ *	Take a completed network device structure and add it to the kernel
+ *	interfaces. A %NETDEV_REGISTER message is sent to the netdev notifier
+ *	chain. 0 is returned on success. A negative errno code is returned
+ *	on a failure to set up the device, or if the name is a duplicate.
+ *
+ *	This is a wrapper around register_netdevice that takes the rtnl semaphore
+ *	and expands the device name if you passed a format string to
+ *	alloc_netdev.
+ */
+int register_netdev(struct net_device *dev)
+{
+	int err;
+
+	rtnl_lock();
+	err = register_netdevice(dev);
+	rtnl_unlock();
+	return err;
+}
+EXPORT_SYMBOL(register_netdev);
+
+int netdev_refcnt_read(const struct net_device *dev)
+{
+	int i, refcnt = 0;
+
+	for_each_possible_cpu(i)
+		refcnt += *per_cpu_ptr(dev->pcpu_refcnt, i);
+	return refcnt;
+}
+EXPORT_SYMBOL(netdev_refcnt_read);
+
+/**
+ * netdev_wait_allrefs - wait until all references are gone.
+ * @dev: target net_device
+ *
+ * This is called when unregistering network devices.
+ *
+ * Any protocol or device that holds a reference should register
+ * for netdevice notification, and cleanup and put back the
+ * reference if they receive an UNREGISTER event.
+ * We can get stuck here if buggy protocols don't correctly
+ * call dev_put.
+ */
+static void netdev_wait_allrefs(struct net_device *dev)
+{
+	unsigned long rebroadcast_time, warning_time;
+	int refcnt;
+
+	linkwatch_forget_dev(dev);
+
+	rebroadcast_time = warning_time = jiffies;
+	refcnt = netdev_refcnt_read(dev);
+
+	while (refcnt != 0) {
+		if (time_after(jiffies, rebroadcast_time + 1 * HZ)) {
+			rtnl_lock();
+
+			/* Rebroadcast unregister notification */
+			call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
+
+			__rtnl_unlock();
+			rcu_barrier();
+			rtnl_lock();
+
+			call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
+			if (test_bit(__LINK_STATE_LINKWATCH_PENDING,
+				     &dev->state)) {
+				/* We must not have linkwatch events
+				 * pending on unregister. If this
+				 * happens, we simply run the queue
+				 * unscheduled, resulting in a noop
+				 * for this device.
+				 */
+				linkwatch_run_queue();
+			}
+
+			__rtnl_unlock();
+
+			rebroadcast_time = jiffies;
+		}
+
+		msleep(250);
+
+		refcnt = netdev_refcnt_read(dev);
+
+		if (time_after(jiffies, warning_time + 10 * HZ)) {
+			pr_emerg("unregister_netdevice: waiting for %s to become free. Usage count = %d\n",
+				 dev->name, refcnt);
+			warning_time = jiffies;
+		}
+	}
+}
+
+/* The sequence is:
+ *
+ *	rtnl_lock();
+ *	...
+ *	register_netdevice(x1);
+ *	register_netdevice(x2);
+ *	...
+ *	unregister_netdevice(y1);
+ *	unregister_netdevice(y2);
+ *      ...
+ *	rtnl_unlock();
+ *	free_netdev(y1);
+ *	free_netdev(y2);
+ *
+ * We are invoked by rtnl_unlock().
+ * This allows us to deal with problems:
+ * 1) We can delete sysfs objects which invoke hotplug
+ *    without deadlocking with linkwatch via keventd.
+ * 2) Since we run with the RTNL semaphore not held, we can sleep
+ *    safely in order to wait for the netdev refcnt to drop to zero.
+ *
+ * We must not return until all unregister events added during
+ * the interval the lock was held have been completed.
+ */
+void netdev_run_todo(void)
+{
+	struct list_head list;
+
+	/* Snapshot list, allow later requests */
+	list_replace_init(&net_todo_list, &list);
+
+	__rtnl_unlock();
+
+
+	/* Wait for rcu callbacks to finish before next phase */
+	if (!list_empty(&list))
+		rcu_barrier();
+
+	while (!list_empty(&list)) {
+		struct net_device *dev
+			= list_first_entry(&list, struct net_device, todo_list);
+		list_del(&dev->todo_list);
+
+		rtnl_lock();
+		call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
+		__rtnl_unlock();
+
+		if (unlikely(dev->reg_state != NETREG_UNREGISTERING)) {
+			pr_err("network todo '%s' but state %d\n",
+			       dev->name, dev->reg_state);
+			dump_stack();
+			continue;
+		}
+
+		dev->reg_state = NETREG_UNREGISTERED;
+
+		on_each_cpu(flush_backlog, dev, 1);
+
+		netdev_wait_allrefs(dev);
+
+		/* paranoia */
+		BUG_ON(netdev_refcnt_read(dev));
+		BUG_ON(!list_empty(&dev->ptype_all));
+		BUG_ON(!list_empty(&dev->ptype_specific));
+		WARN_ON(rcu_access_pointer(dev->ip_ptr));
+		WARN_ON(rcu_access_pointer(dev->ip6_ptr));
+		WARN_ON(dev->dn_ptr);
+
+		if (dev->destructor)
+			dev->destructor(dev);
+
+		/* Report a network device has been unregistered */
+		rtnl_lock();
+		dev_net(dev)->dev_unreg_count--;
+		__rtnl_unlock();
+		wake_up(&netdev_unregistering_wq);
+
+		/* Free network device */
+		kobject_put(&dev->dev.kobj);
+	}
+}
+
+/* Convert net_device_stats to rtnl_link_stats64.  They have the same
+ * fields in the same order, with only the type differing.
+ */
+void netdev_stats_to_stats64(struct rtnl_link_stats64 *stats64,
+			     const struct net_device_stats *netdev_stats)
+{
+#if BITS_PER_LONG == 64
+	BUILD_BUG_ON(sizeof(*stats64) != sizeof(*netdev_stats));
+	memcpy(stats64, netdev_stats, sizeof(*stats64));
+#else
+	size_t i, n = sizeof(*stats64) / sizeof(u64);
+	const unsigned long *src = (const unsigned long *)netdev_stats;
+	u64 *dst = (u64 *)stats64;
+
+	BUILD_BUG_ON(sizeof(*netdev_stats) / sizeof(unsigned long) !=
+		     sizeof(*stats64) / sizeof(u64));
+	for (i = 0; i < n; i++)
+		dst[i] = src[i];
+#endif
+}
+EXPORT_SYMBOL(netdev_stats_to_stats64);
+
+/**
+ *	dev_get_stats	- get network device statistics
+ *	@dev: device to get statistics from
+ *	@storage: place to store stats
+ *
+ *	Get network statistics from device. Return @storage.
+ *	The device driver may provide its own method by setting
+ *	dev->netdev_ops->get_stats64 or dev->netdev_ops->get_stats;
+ *	otherwise the internal statistics structure is used.
+ */
+struct rtnl_link_stats64 *dev_get_stats(struct net_device *dev,
+					struct rtnl_link_stats64 *storage)
+{
+	const struct net_device_ops *ops = dev->netdev_ops;
+
+	if (ops->ndo_get_stats64) {
+		memset(storage, 0, sizeof(*storage));
+		ops->ndo_get_stats64(dev, storage);
+	} else if (ops->ndo_get_stats) {
+		netdev_stats_to_stats64(storage, ops->ndo_get_stats(dev));
+	} else {
+		netdev_stats_to_stats64(storage, &dev->stats);
+	}
+	storage->rx_dropped += atomic_long_read(&dev->rx_dropped);
+	storage->tx_dropped += atomic_long_read(&dev->tx_dropped);
+	return storage;
+}
+EXPORT_SYMBOL(dev_get_stats);
+
+struct netdev_queue *dev_ingress_queue_create(struct net_device *dev)
+{
+	struct netdev_queue *queue = dev_ingress_queue(dev);
+
+#ifdef CONFIG_NET_CLS_ACT
+	if (queue)
+		return queue;
+	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
+	if (!queue)
+		return NULL;
+	netdev_init_one_queue(dev, queue, NULL);
+	RCU_INIT_POINTER(queue->qdisc, &noop_qdisc);
+	queue->qdisc_sleeping = &noop_qdisc;
+	rcu_assign_pointer(dev->ingress_queue, queue);
+#endif
+	return queue;
+}
+
+static const struct ethtool_ops default_ethtool_ops;
+
+void netdev_set_default_ethtool_ops(struct net_device *dev,
+				    const struct ethtool_ops *ops)
+{
+	if (dev->ethtool_ops == &default_ethtool_ops)
+		dev->ethtool_ops = ops;
+}
+EXPORT_SYMBOL_GPL(netdev_set_default_ethtool_ops);
+
+void netdev_freemem(struct net_device *dev)
+{
+	char *addr = (char *)dev - dev->padded;
+
+	kvfree(addr);
+}
+
+/**
+ *	alloc_netdev_mqs - allocate network device
+ *	@sizeof_priv:		size of private data to allocate space for
+ *	@name:			device name format string
+ *	@name_assign_type: 	origin of device name
+ *	@setup:			callback to initialize device
+ *	@txqs:			the number of TX subqueues to allocate
+ *	@rxqs:			the number of RX subqueues to allocate
+ *
+ *	Allocates a struct net_device with private data area for driver use
+ *	and performs basic initialization.  Also allocates subqueue structs
+ *	for each queue on the device.
+ */
+struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name,
+		unsigned char name_assign_type,
+		void (*setup)(struct net_device *),
+		unsigned int txqs, unsigned int rxqs)
+{
+	struct net_device *dev;
+	size_t alloc_size;
+	struct net_device *p;
+
+	BUG_ON(strlen(name) >= sizeof(dev->name));
+
+	if (txqs < 1) {
+		pr_err("alloc_netdev: Unable to allocate device with zero queues\n");
+		return NULL;
+	}
+
+#ifdef CONFIG_SYSFS
+	if (rxqs < 1) {
+		pr_err("alloc_netdev: Unable to allocate device with zero RX queues\n");
+		return NULL;
+	}
+#endif
+
+	alloc_size = sizeof(struct net_device);
+	if (sizeof_priv) {
+		/* ensure 32-byte alignment of private area */
+		alloc_size = ALIGN(alloc_size, NETDEV_ALIGN);
+		alloc_size += sizeof_priv;
+	}
+	/* ensure 32-byte alignment of whole construct */
+	alloc_size += NETDEV_ALIGN - 1;
+
+	p = kzalloc(alloc_size, GFP_KERNEL | __GFP_NOWARN | __GFP_REPEAT);
+	if (!p)
+		p = vzalloc(alloc_size);
+	if (!p)
+		return NULL;
+
+	dev = PTR_ALIGN(p, NETDEV_ALIGN);
+	dev->padded = (char *)dev - (char *)p;
+
+	dev->pcpu_refcnt = alloc_percpu(int);
+	if (!dev->pcpu_refcnt)
+		goto free_dev;
+
+	if (dev_addr_init(dev))
+		goto free_pcpu;
+
+	dev_mc_init(dev);
+	dev_uc_init(dev);
+
+	dev_net_set(dev, &init_net);
+
+	dev->gso_max_size = GSO_MAX_SIZE;
+	dev->gso_max_segs = GSO_MAX_SEGS;
+	dev->gso_min_segs = 0;
+
+	INIT_LIST_HEAD(&dev->napi_list);
+	INIT_LIST_HEAD(&dev->unreg_list);
+	INIT_LIST_HEAD(&dev->close_list);
+	INIT_LIST_HEAD(&dev->link_watch_list);
+	INIT_LIST_HEAD(&dev->adj_list.upper);
+	INIT_LIST_HEAD(&dev->adj_list.lower);
+	INIT_LIST_HEAD(&dev->all_adj_list.upper);
+	INIT_LIST_HEAD(&dev->all_adj_list.lower);
+	INIT_LIST_HEAD(&dev->ptype_all);
+	INIT_LIST_HEAD(&dev->ptype_specific);
+	dev->priv_flags = IFF_XMIT_DST_RELEASE | IFF_XMIT_DST_RELEASE_PERM;
+	setup(dev);
+
+	dev->num_tx_queues = txqs;
+	dev->real_num_tx_queues = txqs;
+	if (netif_alloc_netdev_queues(dev))
+		goto free_all;
+
+#ifdef CONFIG_SYSFS
+	dev->num_rx_queues = rxqs;
+	dev->real_num_rx_queues = rxqs;
+	if (netif_alloc_rx_queues(dev))
+		goto free_all;
+#endif
+
+	strcpy(dev->name, name);
+	dev->name_assign_type = name_assign_type;
+	dev->group = INIT_NETDEV_GROUP;
+	if (!dev->ethtool_ops)
+		dev->ethtool_ops = &default_ethtool_ops;
+	return dev;
+
+free_all:
+	free_netdev(dev);
+	return NULL;
+
+free_pcpu:
+	free_percpu(dev->pcpu_refcnt);
+free_dev:
+	netdev_freemem(dev);
+	return NULL;
+}
+EXPORT_SYMBOL(alloc_netdev_mqs);
+
+/**
+ *	free_netdev - free network device
+ *	@dev: device
+ *
+ *	This function does the last stage of destroying an allocated device
+ * 	interface. The reference to the device object is released.
+ *	If this is the last reference then it will be freed.
+ */
+void free_netdev(struct net_device *dev)
+{
+	struct napi_struct *p, *n;
+
+	netif_free_tx_queues(dev);
+#ifdef CONFIG_SYSFS
+	kvfree(dev->_rx);
+#endif
+
+	kfree(rcu_dereference_protected(dev->ingress_queue, 1));
+
+	/* Flush device addresses */
+	dev_addr_flush(dev);
+
+	list_for_each_entry_safe(p, n, &dev->napi_list, dev_list)
+		netif_napi_del(p);
+
+	free_percpu(dev->pcpu_refcnt);
+	dev->pcpu_refcnt = NULL;
+
+	/*  Compatibility with error handling in drivers */
+	if (dev->reg_state == NETREG_UNINITIALIZED) {
+		netdev_freemem(dev);
+		return;
+	}
+
+	BUG_ON(dev->reg_state != NETREG_UNREGISTERED);
+	dev->reg_state = NETREG_RELEASED;
+
+	/* will free via device release */
+	put_device(&dev->dev);
+}
+EXPORT_SYMBOL(free_netdev);
+
+/**
+ *	synchronize_net -  Synchronize with packet receive processing
+ *
+ *	Wait for packets currently being received to be done.
+ *	Does not block later packets from starting.
+ */
+void synchronize_net(void)
+{
+	might_sleep();
+	if (rtnl_is_locked())
+		synchronize_rcu_expedited();
+	else
+		synchronize_rcu();
+}
+EXPORT_SYMBOL(synchronize_net);
+
+/**
+ *	unregister_netdevice_queue - remove device from the kernel
+ *	@dev: device
+ *	@head: list
+ *
+ *	This function shuts down a device interface and removes it
+ *	from the kernel tables.
+ *	If head not NULL, device is queued to be unregistered later.
+ *
+ *	Callers must hold the rtnl semaphore.  You may want
+ *	unregister_netdev() instead of this.
+ */
+
+void unregister_netdevice_queue(struct net_device *dev, struct list_head *head)
+{
+	ASSERT_RTNL();
+
+	if (head) {
+		list_move_tail(&dev->unreg_list, head);
+	} else {
+		rollback_registered(dev);
+		/* Finish processing unregister after unlock */
+		net_set_todo(dev);
+	}
+}
+EXPORT_SYMBOL(unregister_netdevice_queue);
+
+/**
+ *	unregister_netdevice_many - unregister many devices
+ *	@head: list of devices
+ *
+ *  Note: As most callers use a stack allocated list_head,
+ *  we force a list_del() to make sure stack wont be corrupted later.
+ */
+void unregister_netdevice_many(struct list_head *head)
+{
+	struct net_device *dev;
+
+	if (!list_empty(head)) {
+		rollback_registered_many(head);
+		list_for_each_entry(dev, head, unreg_list)
+			net_set_todo(dev);
+		list_del(head);
+	}
+}
+EXPORT_SYMBOL(unregister_netdevice_many);
+
+/**
+ *	unregister_netdev - remove device from the kernel
+ *	@dev: device
+ *
+ *	This function shuts down a device interface and removes it
+ *	from the kernel tables.
+ *
+ *	This is just a wrapper for unregister_netdevice that takes
+ *	the rtnl semaphore.  In general you want to use this and not
+ *	unregister_netdevice.
+ */
+void unregister_netdev(struct net_device *dev)
+{
+	rtnl_lock();
+	unregister_netdevice(dev);
+	rtnl_unlock();
+}
+EXPORT_SYMBOL(unregister_netdev);
+
+/**
+ *	dev_change_net_namespace - move device to different nethost namespace
+ *	@dev: device
+ *	@net: network namespace
+ *	@pat: If not NULL name pattern to try if the current device name
+ *	      is already taken in the destination network namespace.
+ *
+ *	This function shuts down a device interface and moves it
+ *	to a new network namespace. On success 0 is returned, on
+ *	a failure a netagive errno code is returned.
+ *
+ *	Callers must hold the rtnl semaphore.
+ */
+
+int dev_change_net_namespace(struct net_device *dev, struct net *net, const char *pat)
+{
+	int err;
+
+	ASSERT_RTNL();
+
+	/* Don't allow namespace local devices to be moved. */
+	err = -EINVAL;
+	if (dev->features & NETIF_F_NETNS_LOCAL)
+		goto out;
+
+	/* Ensure the device has been registrered */
+	if (dev->reg_state != NETREG_REGISTERED)
+		goto out;
+
+	/* Get out if there is nothing todo */
+	err = 0;
+	if (net_eq(dev_net(dev), net))
+		goto out;
+
+	/* Pick the destination device name, and ensure
+	 * we can use it in the destination network namespace.
+	 */
+	err = -EEXIST;
+	if (__dev_get_by_name(net, dev->name)) {
+		/* We get here if we can't use the current device name */
+		if (!pat)
+			goto out;
+		if (dev_get_valid_name(net, dev, pat) < 0)
+			goto out;
+	}
+
+	/*
+	 * And now a mini version of register_netdevice unregister_netdevice.
+	 */
+
+	/* If device is running close it first. */
+	dev_close(dev);
+
+	/* And unlink it from device chain */
+	err = -ENODEV;
+	unlist_netdevice(dev);
+
+	synchronize_net();
+
+	/* Shutdown queueing discipline. */
+	dev_shutdown(dev);
+
+	/* Notify protocols, that we are about to destroy
+	   this device. They should clean all the things.
+
+	   Note that dev->reg_state stays at NETREG_REGISTERED.
+	   This is wanted because this way 8021q and macvlan know
+	   the device is just moving and can keep their slaves up.
+	*/
+	call_netdevice_notifiers(NETDEV_UNREGISTER, dev);
+	rcu_barrier();
+	call_netdevice_notifiers(NETDEV_UNREGISTER_FINAL, dev);
+	rtmsg_ifinfo(RTM_DELLINK, dev, ~0U, GFP_KERNEL);
+
+	/*
+	 *	Flush the unicast and multicast chains
+	 */
+	dev_uc_flush(dev);
+	dev_mc_flush(dev);
+
+	/* Send a netdev-removed uevent to the old namespace */
+	kobject_uevent(&dev->dev.kobj, KOBJ_REMOVE);
+	netdev_adjacent_del_links(dev);
+
+	/* Actually switch the network namespace */
+	dev_net_set(dev, net);
+
+	/* If there is an ifindex conflict assign a new one */
+	if (__dev_get_by_index(net, dev->ifindex))
+		dev->ifindex = dev_new_index(net);
+
+	/* Send a netdev-add uevent to the new namespace */
+	kobject_uevent(&dev->dev.kobj, KOBJ_ADD);
+	netdev_adjacent_add_links(dev);
+
+	/* Fixup kobjects */
+	err = device_rename(&dev->dev, dev->name);
+	WARN_ON(err);
+
+	/* Add the device back in the hashes */
+	list_netdevice(dev);
+
+	/* Notify protocols, that a new device appeared. */
+	call_netdevice_notifiers(NETDEV_REGISTER, dev);
+
+	/*
+	 *	Prevent userspace races by waiting until the network
+	 *	device is fully setup before sending notifications.
+	 */
+	rtmsg_ifinfo(RTM_NEWLINK, dev, ~0U, GFP_KERNEL);
+
+	synchronize_net();
+	err = 0;
+out:
+	return err;
+}
+EXPORT_SYMBOL_GPL(dev_change_net_namespace);
+
+static int dev_cpu_callback(struct notifier_block *nfb,
+			    unsigned long action,
+			    void *ocpu)
+{
+	struct sk_buff **list_skb;
+	struct sk_buff *skb;
+	unsigned int cpu, oldcpu = (unsigned long)ocpu;
+	struct softnet_data *sd, *oldsd;
+
+	if (action != CPU_DEAD && action != CPU_DEAD_FROZEN)
+		return NOTIFY_OK;
+
+	local_irq_disable();
+	cpu = smp_processor_id();
+	sd = &per_cpu(softnet_data, cpu);
+	oldsd = &per_cpu(softnet_data, oldcpu);
+
+	/* Find end of our completion_queue. */
+	list_skb = &sd->completion_queue;
+	while (*list_skb)
+		list_skb = &(*list_skb)->next;
+	/* Append completion queue from offline CPU. */
+	*list_skb = oldsd->completion_queue;
+	oldsd->completion_queue = NULL;
+
+	/* Append output queue from offline CPU. */
+	if (oldsd->output_queue) {
+		*sd->output_queue_tailp = oldsd->output_queue;
+		sd->output_queue_tailp = oldsd->output_queue_tailp;
+		oldsd->output_queue = NULL;
+		oldsd->output_queue_tailp = &oldsd->output_queue;
+	}
+	/* Append NAPI poll list from offline CPU, with one exception :
+	 * process_backlog() must be called by cpu owning percpu backlog.
+	 * We properly handle process_queue & input_pkt_queue later.
+	 */
+	while (!list_empty(&oldsd->poll_list)) {
+		struct napi_struct *napi = list_first_entry(&oldsd->poll_list,
+							    struct napi_struct,
+							    poll_list);
+
+		list_del_init(&napi->poll_list);
+		if (napi->poll == process_backlog)
+			napi->state = 0;
+		else
+			____napi_schedule(sd, napi);
+	}
+
+	raise_softirq_irqoff(NET_TX_SOFTIRQ);
+	local_irq_enable();
+
+	/* Process offline CPU's input_pkt_queue */
+	while ((skb = __skb_dequeue(&oldsd->process_queue))) {
+		netif_rx_ni(skb);
+		input_queue_head_incr(oldsd);
+	}
+	while ((skb = skb_dequeue(&oldsd->input_pkt_queue))) {
+		netif_rx_ni(skb);
+		input_queue_head_incr(oldsd);
+	}
+
+	return NOTIFY_OK;
+}
+
+
+/**
+ *	netdev_increment_features - increment feature set by one
+ *	@all: current feature set
+ *	@one: new feature set
+ *	@mask: mask feature set
+ *
+ *	Computes a new feature set after adding a device with feature set
+ *	@one to the master device with current feature set @all.  Will not
+ *	enable anything that is off in @mask. Returns the new feature set.
+ */
+netdev_features_t netdev_increment_features(netdev_features_t all,
+	netdev_features_t one, netdev_features_t mask)
+{
+	if (mask & NETIF_F_GEN_CSUM)
+		mask |= NETIF_F_ALL_CSUM;
+	mask |= NETIF_F_VLAN_CHALLENGED;
+
+	all |= one & (NETIF_F_ONE_FOR_ALL|NETIF_F_ALL_CSUM) & mask;
+	all &= one | ~NETIF_F_ALL_FOR_ALL;
+
+	/* If one device supports hw checksumming, set for all. */
+	if (all & NETIF_F_GEN_CSUM)
+		all &= ~(NETIF_F_ALL_CSUM & ~NETIF_F_GEN_CSUM);
+
+	return all;
+}
+EXPORT_SYMBOL(netdev_increment_features);
+
+static struct hlist_head * __net_init netdev_create_hash(void)
+{
+	int i;
+	struct hlist_head *hash;
+
+	hash = kmalloc(sizeof(*hash) * NETDEV_HASHENTRIES, GFP_KERNEL);
+	if (hash != NULL)
+		for (i = 0; i < NETDEV_HASHENTRIES; i++)
+			INIT_HLIST_HEAD(&hash[i]);
+
+	return hash;
+}
+
+/* Initialize per network namespace state */
+static int __net_init netdev_init(struct net *net)
+{
+	if (net != &init_net)
+		INIT_LIST_HEAD(&net->dev_base_head);
+
+	net->dev_name_head = netdev_create_hash();
+	if (net->dev_name_head == NULL)
+		goto err_name;
+
+	net->dev_index_head = netdev_create_hash();
+	if (net->dev_index_head == NULL)
+		goto err_idx;
+
+	return 0;
+
+err_idx:
+	kfree(net->dev_name_head);
+err_name:
+	return -ENOMEM;
+}
+
+/**
+ *	netdev_drivername - network driver for the device
+ *	@dev: network device
+ *
+ *	Determine network driver for device.
+ */
+const char *netdev_drivername(const struct net_device *dev)
+{
+	const struct device_driver *driver;
+	const struct device *parent;
+	const char *empty = "";
+
+	parent = dev->dev.parent;
+	if (!parent)
+		return empty;
+
+	driver = parent->driver;
+	if (driver && driver->name)
+		return driver->name;
+	return empty;
+}
+
+static void __netdev_printk(const char *level, const struct net_device *dev,
+			    struct va_format *vaf)
+{
+	if (dev && dev->dev.parent) {
+		dev_printk_emit(level[1] - '0',
+				dev->dev.parent,
+				"%s %s %s%s: %pV",
+				dev_driver_string(dev->dev.parent),
+				dev_name(dev->dev.parent),
+				netdev_name(dev), netdev_reg_state(dev),
+				vaf);
+	} else if (dev) {
+		printk("%s%s%s: %pV",
+		       level, netdev_name(dev), netdev_reg_state(dev), vaf);
+	} else {
+		printk("%s(NULL net_device): %pV", level, vaf);
+	}
+}
+
+void netdev_printk(const char *level, const struct net_device *dev,
+		   const char *format, ...)
+{
+	struct va_format vaf;
+	va_list args;
+
+	va_start(args, format);
+
+	vaf.fmt = format;
+	vaf.va = &args;
+
+	__netdev_printk(level, dev, &vaf);
+
+	va_end(args);
+}
+EXPORT_SYMBOL(netdev_printk);
+
+#define define_netdev_printk_level(func, level)			\
+void func(const struct net_device *dev, const char *fmt, ...)	\
+{								\
+	struct va_format vaf;					\
+	va_list args;						\
+								\
+	va_start(args, fmt);					\
+								\
+	vaf.fmt = fmt;						\
+	vaf.va = &args;						\
+								\
+	__netdev_printk(level, dev, &vaf);			\
+								\
+	va_end(args);						\
+}								\
+EXPORT_SYMBOL(func);
+
+define_netdev_printk_level(netdev_emerg, KERN_EMERG);
+define_netdev_printk_level(netdev_alert, KERN_ALERT);
+define_netdev_printk_level(netdev_crit, KERN_CRIT);
+define_netdev_printk_level(netdev_err, KERN_ERR);
+define_netdev_printk_level(netdev_warn, KERN_WARNING);
+define_netdev_printk_level(netdev_notice, KERN_NOTICE);
+define_netdev_printk_level(netdev_info, KERN_INFO);
+
+static void __net_exit netdev_exit(struct net *net)
+{
+	kfree(net->dev_name_head);
+	kfree(net->dev_index_head);
+}
+
+static struct pernet_operations __net_initdata netdev_net_ops = {
+	.init = netdev_init,
+	.exit = netdev_exit,
+};
+
+static void __net_exit default_device_exit(struct net *net)
+{
+	struct net_device *dev, *aux;
+	/*
+	 * Push all migratable network devices back to the
+	 * initial network namespace
+	 */
+	rtnl_lock();
+	for_each_netdev_safe(net, dev, aux) {
+		int err;
+		char fb_name[IFNAMSIZ];
+
+		/* Ignore unmoveable devices (i.e. loopback) */
+		if (dev->features & NETIF_F_NETNS_LOCAL)
+			continue;
+
+		/* Leave virtual devices for the generic cleanup */
+		if (dev->rtnl_link_ops)
+			continue;
+
+		/* Push remaining network devices to init_net */
+		snprintf(fb_name, IFNAMSIZ, "dev%d", dev->ifindex);
+		err = dev_change_net_namespace(dev, &init_net, fb_name);
+		if (err) {
+			pr_emerg("%s: failed to move %s to init_net: %d\n",
+				 __func__, dev->name, err);
+			BUG();
+		}
+	}
+	rtnl_unlock();
+}
+
+static void __net_exit rtnl_lock_unregistering(struct list_head *net_list)
+{
+	/* Return with the rtnl_lock held when there are no network
+	 * devices unregistering in any network namespace in net_list.
+	 */
+	struct net *net;
+	bool unregistering;
+	DEFINE_WAIT_FUNC(wait, woken_wake_function);
+
+	add_wait_queue(&netdev_unregistering_wq, &wait);
+	for (;;) {
+		unregistering = false;
+		rtnl_lock();
+		list_for_each_entry(net, net_list, exit_list) {
+			if (net->dev_unreg_count > 0) {
+				unregistering = true;
+				break;
+			}
+		}
+		if (!unregistering)
+			break;
+		__rtnl_unlock();
+
+		wait_woken(&wait, TASK_UNINTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
+	}
+	remove_wait_queue(&netdev_unregistering_wq, &wait);
+}
+
+static void __net_exit default_device_exit_batch(struct list_head *net_list)
+{
+	/* At exit all network devices most be removed from a network
+	 * namespace.  Do this in the reverse order of registration.
+	 * Do this across as many network namespaces as possible to
+	 * improve batching efficiency.
+	 */
+	struct net_device *dev;
+	struct net *net;
+	LIST_HEAD(dev_kill_list);
+
+	/* To prevent network device cleanup code from dereferencing
+	 * loopback devices or network devices that have been freed
+	 * wait here for all pending unregistrations to complete,
+	 * before unregistring the loopback device and allowing the
+	 * network namespace be freed.
+	 *
+	 * The netdev todo list containing all network devices
+	 * unregistrations that happen in default_device_exit_batch
+	 * will run in the rtnl_unlock() at the end of
+	 * default_device_exit_batch.
+	 */
+	rtnl_lock_unregistering(net_list);
+	list_for_each_entry(net, net_list, exit_list) {
+		for_each_netdev_reverse(net, dev) {
+			if (dev->rtnl_link_ops && dev->rtnl_link_ops->dellink)
+				dev->rtnl_link_ops->dellink(dev, &dev_kill_list);
+			else
+				unregister_netdevice_queue(dev, &dev_kill_list);
+		}
+	}
+	unregister_netdevice_many(&dev_kill_list);
+	rtnl_unlock();
+}
+
+static struct pernet_operations __net_initdata default_device_ops = {
+	.exit = default_device_exit,
+	.exit_batch = default_device_exit_batch,
+};
+
+/*
+ *	Initialize the DEV module. At boot time this walks the device list and
+ *	unhooks any devices that fail to initialise (normally hardware not
+ *	present) and leaves us with a valid list of present and active devices.
+ *
+ */
+
+/*
+ *       This is called single threaded during boot, so no need
+ *       to take the rtnl semaphore.
+ */
+static int __init net_dev_init(void)
+{
+	int i, rc = -ENOMEM;
+
+	BUG_ON(!dev_boot_phase);
+
+	if (dev_proc_init())
+		goto out;
+
+	if (netdev_kobject_init())
+		goto out;
+
+	INIT_LIST_HEAD(&ptype_all);
+	for (i = 0; i < PTYPE_HASH_SIZE; i++)
+		INIT_LIST_HEAD(&ptype_base[i]);
+
+	INIT_LIST_HEAD(&offload_base);
+
+	if (register_pernet_subsys(&netdev_net_ops))
+		goto out;
+
+	/*
+	 *	Initialise the packet receive queues.
+	 */
+
+	for_each_possible_cpu(i) {
+		struct softnet_data *sd = &per_cpu(softnet_data, i);
+
+		skb_queue_head_init(&sd->input_pkt_queue);
+		skb_queue_head_init(&sd->process_queue);
+		INIT_LIST_HEAD(&sd->poll_list);
+		sd->output_queue_tailp = &sd->output_queue;
+#ifdef CONFIG_RPS
+		sd->csd.func = rps_trigger_softirq;
+		sd->csd.info = sd;
+		sd->cpu = i;
+#endif
+
+		sd->backlog.poll = process_backlog;
+		sd->backlog.weight = weight_p;
+	}
+
+	dev_boot_phase = 0;
+
+	/* The loopback device is special if any other network devices
+	 * is present in a network namespace the loopback device must
+	 * be present. Since we now dynamically allocate and free the
+	 * loopback device ensure this invariant is maintained by
+	 * keeping the loopback device as the first device on the
+	 * list of network devices.  Ensuring the loopback devices
+	 * is the first device that appears and the last network device
+	 * that disappears.
+	 */
+	if (register_pernet_device(&loopback_net_ops))
+		goto out;
+
+	if (register_pernet_device(&default_device_ops))
+		goto out;
+
+	open_softirq(NET_TX_SOFTIRQ, net_tx_action);
+	open_softirq(NET_RX_SOFTIRQ, net_rx_action);
+
+	hotcpu_notifier(dev_cpu_callback, 0);
+	dst_init();
+	rc = 0;
+out:
+	return rc;
+}
+
+subsys_initcall(net_dev_init);