Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / net / core / dev.c
diff --git a/kernel/net/core/dev.c b/kernel/net/core/dev.c
new file mode 100644 (file)
index 0000000..349de9d
--- /dev/null
@@ -0,0 +1,7571 @@
+/*
+ *     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 DEFINE_MUTEX(devnet_rename_mutex);
+
+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
+       raw_spin_lock(&sd->input_pkt_queue.raw_lock);
+#endif
+}
+
+static inline void rps_unlock(struct softnet_data *sd)
+{
+#ifdef CONFIG_RPS
+       raw_spin_unlock(&sd->input_pkt_queue.raw_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)) {
+               mutex_lock(&devnet_rename_mutex);
+               mutex_unlock(&devnet_rename_mutex);
+               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;
+
+       mutex_lock(&devnet_rename_mutex);
+       __raw_write_seqcount_begin(&devnet_rename_seq);
+
+       if (strncmp(newname, dev->name, IFNAMSIZ) == 0)
+               goto outunlock;
+
+       memcpy(oldname, dev->name, IFNAMSIZ);
+
+       err = dev_get_valid_name(net, dev, newname);
+       if (err < 0)
+               goto outunlock;
+
+       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;
+               err = ret;
+               goto outunlock;
+       }
+
+       __raw_write_seqcount_end(&devnet_rename_seq);
+       mutex_unlock(&devnet_rename_mutex);
+
+       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;
+                       mutex_lock(&devnet_rename_mutex);
+                       __raw_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;
+
+outunlock:
+       __raw_write_seqcount_end(&devnet_rename_seq);
+       mutex_unlock(&devnet_rename_mutex);
+       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);
+       preempt_check_resched_rt();
+}
+
+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);
+       preempt_check_resched_rt();
+}
+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);
+       preempt_check_resched_rt();
+
+       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;
+
+               migrate_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();
+               migrate_enable();
+       } else
+#endif
+       {
+               unsigned int qtail;
+               ret = enqueue_to_backlog(skb, get_cpu_light(), &qtail);
+               put_cpu_light();
+       }
+       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);
+
+       local_bh_disable();
+       err = netif_rx_internal(skb);
+       local_bh_enable();
+
+       return err;
+}
+EXPORT_SYMBOL(netif_rx_ni);
+
+#ifdef CONFIG_PREEMPT_RT_FULL
+/*
+ * RT runs ksoftirqd as a real time thread and the root_lock is a
+ * "sleeping spinlock". If the trylock fails then we can go into an
+ * infinite loop when ksoftirqd preempted the task which actually
+ * holds the lock, because we requeue q and raise NET_TX softirq
+ * causing ksoftirqd to loop forever.
+ *
+ * It's safe to use spin_lock on RT here as softirqs run in thread
+ * context and cannot deadlock against the thread which is holding
+ * root_lock.
+ *
+ * On !RT the trylock might fail, but there we bail out from the
+ * softirq loop after 10 attempts which we can't do on RT. And the
+ * task holding root_lock cannot be preempted, so the only downside of
+ * that trylock is that we need 10 loops to decide that we should have
+ * given up in the first one :)
+ */
+static inline int take_root_lock(spinlock_t *lock)
+{
+       spin_lock(lock);
+       return 1;
+}
+#else
+static inline int take_root_lock(spinlock_t *lock)
+{
+       return spin_trylock(lock);
+}
+#endif
+
+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 (take_root_lock(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);
+                       __skb_queue_tail(&sd->tofree_queue, 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);
+                       __skb_queue_tail(&sd->tofree_queue, skb);
+                       input_queue_head_incr(sd);
+               }
+       }
+
+       if (!skb_queue_empty(&sd->tofree_queue))
+               raise_softirq_irqoff(NET_RX_SOFTIRQ);
+}
+
+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();
+               preempt_check_resched_rt();
+
+               /* 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();
+       preempt_check_resched_rt();
+}
+
+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);
+       preempt_check_resched_rt();
+}
+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();
+       preempt_check_resched_rt();
+
+       /* 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);
+       }
+       while ((skb = __skb_dequeue(&oldsd->tofree_queue))) {
+               kfree_skb(skb);
+       }
+
+       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_raw(&sd->input_pkt_queue);
+               skb_queue_head_init_raw(&sd->process_queue);
+               skb_queue_head_init_raw(&sd->tofree_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);