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	Version: linux-6.0.1 spark-3.0.0 hadoop-3.2.0-src hadoop-3.3.0-src spark-2.4.7 linux-4.15.13 hadoop-2.7.4-src Revert   Change

 // SPDX-License-Identifier: GPL-2.0
 /* Copyright (C) B.A.T.M.A.N. contributors:
  *
  * Marek Lindner, Simon Wunderlich, Antonio Quartulli
  */
 
 #include "translation-table.h"
 #include "main.h"
 
 #include <linux/atomic.h>
 #include <linux/bitops.h>
 #include <linux/build_bug.h>
 #include <linux/byteorder/generic.h>
 #include <linux/cache.h>
 #include <linux/compiler.h>
 #include <linux/container_of.h>
 #include <linux/crc32c.h>
 #include <linux/errno.h>
 #include <linux/etherdevice.h>
 #include <linux/gfp.h>
 #include <linux/if_ether.h>
 #include <linux/init.h>
 #include <linux/jhash.h>
 #include <linux/jiffies.h>
 #include <linux/kref.h>
 #include <linux/list.h>
 #include <linux/lockdep.h>
 #include <linux/net.h>
 #include <linux/netdevice.h>
 #include <linux/netlink.h>
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
 #include <linux/skbuff.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/stddef.h>
 #include <linux/string.h>
 #include <linux/workqueue.h>
 #include <net/genetlink.h>
 #include <net/netlink.h>
 #include <net/sock.h>
 #include <uapi/linux/batadv_packet.h>
 #include <uapi/linux/batman_adv.h>
 
 #include "bridge_loop_avoidance.h"
 #include "hard-interface.h"
 #include "hash.h"
 #include "log.h"
 #include "netlink.h"
 #include "originator.h"
 #include "soft-interface.h"
 #include "tvlv.h"
 
 static struct kmem_cache *batadv_tl_cache __read_mostly;
 static struct kmem_cache *batadv_tg_cache __read_mostly;
 static struct kmem_cache *batadv_tt_orig_cache __read_mostly;
 static struct kmem_cache *batadv_tt_change_cache __read_mostly;
 static struct kmem_cache *batadv_tt_req_cache __read_mostly;
 static struct kmem_cache *batadv_tt_roam_cache __read_mostly;
 
 /* hash class keys */
 static struct lock_class_key batadv_tt_local_hash_lock_class_key;
 static struct lock_class_key batadv_tt_global_hash_lock_class_key;
 
 static void batadv_send_roam_adv(struct batadv_priv *bat_priv, u8 *client,
                  unsigned short vid,
                  struct batadv_orig_node *orig_node);
 static void batadv_tt_purge(struct work_struct *work);
 static void
 batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry);
 static void batadv_tt_global_del(struct batadv_priv *bat_priv,
                  struct batadv_orig_node *orig_node,
                  const unsigned char *addr,
                  unsigned short vid, const char *message,
                  bool roaming);
 
 /**
  * batadv_compare_tt() - check if two TT entries are the same
  * @node: the list element pointer of the first TT entry
  * @data2: pointer to the tt_common_entry of the second TT entry
  *
  * Compare the MAC address and the VLAN ID of the two TT entries and check if
  * they are the same TT client.
  * Return: true if the two TT clients are the same, false otherwise
  */
 static bool batadv_compare_tt(const struct hlist_node *node, const void *data2)
 {
     const void *data1 = container_of(node, struct batadv_tt_common_entry,
                      hash_entry);
     const struct batadv_tt_common_entry *tt1 = data1;
     const struct batadv_tt_common_entry *tt2 = data2;
 
     return (tt1->vid == tt2->vid) && batadv_compare_eth(data1, data2);
 }
 
 /**
  * batadv_choose_tt() - return the index of the tt entry in the hash table
  * @data: pointer to the tt_common_entry object to map
  * @size: the size of the hash table
  *
  * Return: the hash index where the object represented by 'data' should be
  * stored at.
  */
 static inline u32 batadv_choose_tt(const void *data, u32 size)
 {
     const struct batadv_tt_common_entry *tt;
     u32 hash = 0;
 
     tt = data;
     hash = jhash(&tt->addr, ETH_ALEN, hash);
     hash = jhash(&tt->vid, sizeof(tt->vid), hash);
 
     return hash % size;
 }
 
 /**
  * batadv_tt_hash_find() - look for a client in the given hash table
  * @hash: the hash table to search
  * @addr: the mac address of the client to look for
  * @vid: VLAN identifier
  *
  * Return: a pointer to the tt_common struct belonging to the searched client if
  * found, NULL otherwise.
  */
 static struct batadv_tt_common_entry *
 batadv_tt_hash_find(struct batadv_hashtable *hash, const u8 *addr,
             unsigned short vid)
 {
     struct hlist_head *head;
     struct batadv_tt_common_entry to_search, *tt, *tt_tmp = NULL;
     u32 index;
 
     if (!hash)
         return NULL;
 
     ether_addr_copy(to_search.addr, addr);
     to_search.vid = vid;
 
     index = batadv_choose_tt(&to_search, hash->size);
     head = &hash->table[index];
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(tt, head, hash_entry) {
         if (!batadv_compare_eth(tt, addr))
             continue;
 
         if (tt->vid != vid)
             continue;
 
         if (!kref_get_unless_zero(&tt->refcount))
             continue;
 
         tt_tmp = tt;
         break;
     }
     rcu_read_unlock();
 
     return tt_tmp;
 }
 
 /**
  * batadv_tt_local_hash_find() - search the local table for a given client
  * @bat_priv: the bat priv with all the soft interface information
  * @addr: the mac address of the client to look for
  * @vid: VLAN identifier
  *
  * Return: a pointer to the corresponding tt_local_entry struct if the client is
  * found, NULL otherwise.
  */
 static struct batadv_tt_local_entry *
 batadv_tt_local_hash_find(struct batadv_priv *bat_priv, const u8 *addr,
               unsigned short vid)
 {
     struct batadv_tt_common_entry *tt_common_entry;
     struct batadv_tt_local_entry *tt_local_entry = NULL;
 
     tt_common_entry = batadv_tt_hash_find(bat_priv->tt.local_hash, addr,
                           vid);
     if (tt_common_entry)
         tt_local_entry = container_of(tt_common_entry,
                           struct batadv_tt_local_entry,
                           common);
     return tt_local_entry;
 }
 
 /**
  * batadv_tt_global_hash_find() - search the global table for a given client
  * @bat_priv: the bat priv with all the soft interface information
  * @addr: the mac address of the client to look for
  * @vid: VLAN identifier
  *
  * Return: a pointer to the corresponding tt_global_entry struct if the client
  * is found, NULL otherwise.
  */
 struct batadv_tt_global_entry *
 batadv_tt_global_hash_find(struct batadv_priv *bat_priv, const u8 *addr,
                unsigned short vid)
 {
     struct batadv_tt_common_entry *tt_common_entry;
     struct batadv_tt_global_entry *tt_global_entry = NULL;
 
     tt_common_entry = batadv_tt_hash_find(bat_priv->tt.global_hash, addr,
                           vid);
     if (tt_common_entry)
         tt_global_entry = container_of(tt_common_entry,
                            struct batadv_tt_global_entry,
                            common);
     return tt_global_entry;
 }
 
 /**
  * batadv_tt_local_entry_free_rcu() - free the tt_local_entry
  * @rcu: rcu pointer of the tt_local_entry
  */
 static void batadv_tt_local_entry_free_rcu(struct rcu_head *rcu)
 {
     struct batadv_tt_local_entry *tt_local_entry;
 
     tt_local_entry = container_of(rcu, struct batadv_tt_local_entry,
                       common.rcu);
 
     kmem_cache_free(batadv_tl_cache, tt_local_entry);
 }
 
 /**
  * batadv_tt_local_entry_release() - release tt_local_entry from lists and queue
  *  for free after rcu grace period
  * @ref: kref pointer of the nc_node
  */
 static void batadv_tt_local_entry_release(struct kref *ref)
 {
     struct batadv_tt_local_entry *tt_local_entry;
 
     tt_local_entry = container_of(ref, struct batadv_tt_local_entry,
                       common.refcount);
 
     batadv_softif_vlan_put(tt_local_entry->vlan);
 
     call_rcu(&tt_local_entry->common.rcu, batadv_tt_local_entry_free_rcu);
 }
 
 /**
  * batadv_tt_local_entry_put() - decrement the tt_local_entry refcounter and
  *  possibly release it
  * @tt_local_entry: tt_local_entry to be free'd
  */
 static void
 batadv_tt_local_entry_put(struct batadv_tt_local_entry *tt_local_entry)
 {
     if (!tt_local_entry)
         return;
 
     kref_put(&tt_local_entry->common.refcount,
          batadv_tt_local_entry_release);
 }
 
 /**
  * batadv_tt_global_entry_free_rcu() - free the tt_global_entry
  * @rcu: rcu pointer of the tt_global_entry
  */
 static void batadv_tt_global_entry_free_rcu(struct rcu_head *rcu)
 {
     struct batadv_tt_global_entry *tt_global_entry;
 
     tt_global_entry = container_of(rcu, struct batadv_tt_global_entry,
                        common.rcu);
 
     kmem_cache_free(batadv_tg_cache, tt_global_entry);
 }
 
 /**
  * batadv_tt_global_entry_release() - release tt_global_entry from lists and
  *  queue for free after rcu grace period
  * @ref: kref pointer of the nc_node
  */
 void batadv_tt_global_entry_release(struct kref *ref)
 {
     struct batadv_tt_global_entry *tt_global_entry;
 
     tt_global_entry = container_of(ref, struct batadv_tt_global_entry,
                        common.refcount);
 
     batadv_tt_global_del_orig_list(tt_global_entry);
 
     call_rcu(&tt_global_entry->common.rcu, batadv_tt_global_entry_free_rcu);
 }
 
 /**
  * batadv_tt_global_hash_count() - count the number of orig entries
  * @bat_priv: the bat priv with all the soft interface information
  * @addr: the mac address of the client to count entries for
  * @vid: VLAN identifier
  *
  * Return: the number of originators advertising the given address/data
  * (excluding our self).
  */
 int batadv_tt_global_hash_count(struct batadv_priv *bat_priv,
                 const u8 *addr, unsigned short vid)
 {
     struct batadv_tt_global_entry *tt_global_entry;
     int count;
 
     tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
     if (!tt_global_entry)
         return 0;
 
     count = atomic_read(&tt_global_entry->orig_list_count);
     batadv_tt_global_entry_put(tt_global_entry);
 
     return count;
 }
 
 /**
  * batadv_tt_local_size_mod() - change the size by v of the local table
  *  identified by vid
  * @bat_priv: the bat priv with all the soft interface information
  * @vid: the VLAN identifier of the sub-table to change
  * @v: the amount to sum to the local table size
  */
 static void batadv_tt_local_size_mod(struct batadv_priv *bat_priv,
                      unsigned short vid, int v)
 {
     struct batadv_softif_vlan *vlan;
 
     vlan = batadv_softif_vlan_get(bat_priv, vid);
     if (!vlan)
         return;
 
     atomic_add(v, &vlan->tt.num_entries);
 
     batadv_softif_vlan_put(vlan);
 }
 
 /**
  * batadv_tt_local_size_inc() - increase by one the local table size for the
  *  given vid
  * @bat_priv: the bat priv with all the soft interface information
  * @vid: the VLAN identifier
  */
 static void batadv_tt_local_size_inc(struct batadv_priv *bat_priv,
                      unsigned short vid)
 {
     batadv_tt_local_size_mod(bat_priv, vid, 1);
 }
 
 /**
  * batadv_tt_local_size_dec() - decrease by one the local table size for the
  *  given vid
  * @bat_priv: the bat priv with all the soft interface information
  * @vid: the VLAN identifier
  */
 static void batadv_tt_local_size_dec(struct batadv_priv *bat_priv,
                      unsigned short vid)
 {
     batadv_tt_local_size_mod(bat_priv, vid, -1);
 }
 
 /**
  * batadv_tt_global_size_mod() - change the size by v of the global table
  *  for orig_node identified by vid
  * @orig_node: the originator for which the table has to be modified
  * @vid: the VLAN identifier
  * @v: the amount to sum to the global table size
  */
 static void batadv_tt_global_size_mod(struct batadv_orig_node *orig_node,
                       unsigned short vid, int v)
 {
     struct batadv_orig_node_vlan *vlan;
 
     vlan = batadv_orig_node_vlan_new(orig_node, vid);
     if (!vlan)
         return;
 
     if (atomic_add_return(v, &vlan->tt.num_entries) == 0) {
         spin_lock_bh(&orig_node->vlan_list_lock);
         if (!hlist_unhashed(&vlan->list)) {
             hlist_del_init_rcu(&vlan->list);
             batadv_orig_node_vlan_put(vlan);
         }
         spin_unlock_bh(&orig_node->vlan_list_lock);
     }
 
     batadv_orig_node_vlan_put(vlan);
 }
 
 /**
  * batadv_tt_global_size_inc() - increase by one the global table size for the
  *  given vid
  * @orig_node: the originator which global table size has to be decreased
  * @vid: the vlan identifier
  */
 static void batadv_tt_global_size_inc(struct batadv_orig_node *orig_node,
                       unsigned short vid)
 {
     batadv_tt_global_size_mod(orig_node, vid, 1);
 }
 
 /**
  * batadv_tt_global_size_dec() - decrease by one the global table size for the
  *  given vid
  * @orig_node: the originator which global table size has to be decreased
  * @vid: the vlan identifier
  */
 static void batadv_tt_global_size_dec(struct batadv_orig_node *orig_node,
                       unsigned short vid)
 {
     batadv_tt_global_size_mod(orig_node, vid, -1);
 }
 
 /**
  * batadv_tt_orig_list_entry_free_rcu() - free the orig_entry
  * @rcu: rcu pointer of the orig_entry
  */
 static void batadv_tt_orig_list_entry_free_rcu(struct rcu_head *rcu)
 {
     struct batadv_tt_orig_list_entry *orig_entry;
 
     orig_entry = container_of(rcu, struct batadv_tt_orig_list_entry, rcu);
 
     kmem_cache_free(batadv_tt_orig_cache, orig_entry);
 }
 
 /**
  * batadv_tt_orig_list_entry_release() - release tt orig entry from lists and
  *  queue for free after rcu grace period
  * @ref: kref pointer of the tt orig entry
  */
 static void batadv_tt_orig_list_entry_release(struct kref *ref)
 {
     struct batadv_tt_orig_list_entry *orig_entry;
 
     orig_entry = container_of(ref, struct batadv_tt_orig_list_entry,
                   refcount);
 
     batadv_orig_node_put(orig_entry->orig_node);
     call_rcu(&orig_entry->rcu, batadv_tt_orig_list_entry_free_rcu);
 }
 
 /**
  * batadv_tt_orig_list_entry_put() - decrement the tt orig entry refcounter and
  *  possibly release it
  * @orig_entry: tt orig entry to be free'd
  */
 static void
 batadv_tt_orig_list_entry_put(struct batadv_tt_orig_list_entry *orig_entry)
 {
     if (!orig_entry)
         return;
 
     kref_put(&orig_entry->refcount, batadv_tt_orig_list_entry_release);
 }
 
 /**
  * batadv_tt_local_event() - store a local TT event (ADD/DEL)
  * @bat_priv: the bat priv with all the soft interface information
  * @tt_local_entry: the TT entry involved in the event
  * @event_flags: flags to store in the event structure
  */
 static void batadv_tt_local_event(struct batadv_priv *bat_priv,
                   struct batadv_tt_local_entry *tt_local_entry,
                   u8 event_flags)
 {
     struct batadv_tt_change_node *tt_change_node, *entry, *safe;
     struct batadv_tt_common_entry *common = &tt_local_entry->common;
     u8 flags = common->flags | event_flags;
     bool event_removed = false;
     bool del_op_requested, del_op_entry;
 
     tt_change_node = kmem_cache_alloc(batadv_tt_change_cache, GFP_ATOMIC);
     if (!tt_change_node)
         return;
 
     tt_change_node->change.flags = flags;
     memset(tt_change_node->change.reserved, 0,
            sizeof(tt_change_node->change.reserved));
     ether_addr_copy(tt_change_node->change.addr, common->addr);
     tt_change_node->change.vid = htons(common->vid);
 
     del_op_requested = flags & BATADV_TT_CLIENT_DEL;
 
     /* check for ADD+DEL or DEL+ADD events */
     spin_lock_bh(&bat_priv->tt.changes_list_lock);
     list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
                  list) {
         if (!batadv_compare_eth(entry->change.addr, common->addr))
             continue;
 
         /* DEL+ADD in the same orig interval have no effect and can be
          * removed to avoid silly behaviour on the receiver side. The
          * other way around (ADD+DEL) can happen in case of roaming of
          * a client still in the NEW state. Roaming of NEW clients is
          * now possible due to automatically recognition of "temporary"
          * clients
          */
         del_op_entry = entry->change.flags & BATADV_TT_CLIENT_DEL;
         if (!del_op_requested && del_op_entry)
             goto del;
         if (del_op_requested && !del_op_entry)
             goto del;
 
         /* this is a second add in the same originator interval. It
          * means that flags have been changed: update them!
          */
         if (!del_op_requested && !del_op_entry)
             entry->change.flags = flags;
 
         continue;
 del:
         list_del(&entry->list);
         kmem_cache_free(batadv_tt_change_cache, entry);
         kmem_cache_free(batadv_tt_change_cache, tt_change_node);
         event_removed = true;
         goto unlock;
     }
 
     /* track the change in the OGMinterval list */
     list_add_tail(&tt_change_node->list, &bat_priv->tt.changes_list);
 
 unlock:
     spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 
     if (event_removed)
         atomic_dec(&bat_priv->tt.local_changes);
     else
         atomic_inc(&bat_priv->tt.local_changes);
 }
 
 /**
  * batadv_tt_len() - compute length in bytes of given number of tt changes
  * @changes_num: number of tt changes
  *
  * Return: computed length in bytes.
  */
 static int batadv_tt_len(int changes_num)
 {
     return changes_num * sizeof(struct batadv_tvlv_tt_change);
 }
 
 /**
  * batadv_tt_entries() - compute the number of entries fitting in tt_len bytes
  * @tt_len: available space
  *
  * Return: the number of entries.
  */
 static u16 batadv_tt_entries(u16 tt_len)
 {
     return tt_len / batadv_tt_len(1);
 }
 
 /**
  * batadv_tt_local_table_transmit_size() - calculates the local translation
  *  table size when transmitted over the air
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Return: local translation table size in bytes.
  */
 static int batadv_tt_local_table_transmit_size(struct batadv_priv *bat_priv)
 {
     u16 num_vlan = 0;
     u16 tt_local_entries = 0;
     struct batadv_softif_vlan *vlan;
     int hdr_size;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
         num_vlan++;
         tt_local_entries += atomic_read(&vlan->tt.num_entries);
     }
     rcu_read_unlock();
 
     /* header size of tvlv encapsulated tt response payload */
     hdr_size = sizeof(struct batadv_unicast_tvlv_packet);
     hdr_size += sizeof(struct batadv_tvlv_hdr);
     hdr_size += sizeof(struct batadv_tvlv_tt_data);
     hdr_size += num_vlan * sizeof(struct batadv_tvlv_tt_vlan_data);
 
     return hdr_size + batadv_tt_len(tt_local_entries);
 }
 
 static int batadv_tt_local_init(struct batadv_priv *bat_priv)
 {
     if (bat_priv->tt.local_hash)
         return 0;
 
     bat_priv->tt.local_hash = batadv_hash_new(1024);
 
     if (!bat_priv->tt.local_hash)
         return -ENOMEM;
 
     batadv_hash_set_lock_class(bat_priv->tt.local_hash,
                    &batadv_tt_local_hash_lock_class_key);
 
     return 0;
 }
 
 static void batadv_tt_global_free(struct batadv_priv *bat_priv,
                   struct batadv_tt_global_entry *tt_global,
                   const char *message)
 {
     struct batadv_tt_global_entry *tt_removed_entry;
     struct hlist_node *tt_removed_node;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Deleting global tt entry %pM (vid: %d): %s\n",
            tt_global->common.addr,
            batadv_print_vid(tt_global->common.vid), message);
 
     tt_removed_node = batadv_hash_remove(bat_priv->tt.global_hash,
                          batadv_compare_tt,
                          batadv_choose_tt,
                          &tt_global->common);
     if (!tt_removed_node)
         return;
 
     /* drop reference of remove hash entry */
     tt_removed_entry = hlist_entry(tt_removed_node,
                        struct batadv_tt_global_entry,
                        common.hash_entry);
     batadv_tt_global_entry_put(tt_removed_entry);
 }
 
 /**
  * batadv_tt_local_add() - add a new client to the local table or update an
  *  existing client
  * @soft_iface: netdev struct of the mesh interface
  * @addr: the mac address of the client to add
  * @vid: VLAN identifier
  * @ifindex: index of the interface where the client is connected to (useful to
  *  identify wireless clients)
  * @mark: the value contained in the skb->mark field of the received packet (if
  *  any)
  *
  * Return: true if the client was successfully added, false otherwise.
  */
 bool batadv_tt_local_add(struct net_device *soft_iface, const u8 *addr,
              unsigned short vid, int ifindex, u32 mark)
 {
     struct batadv_priv *bat_priv = netdev_priv(soft_iface);
     struct batadv_tt_local_entry *tt_local;
     struct batadv_tt_global_entry *tt_global = NULL;
     struct net *net = dev_net(soft_iface);
     struct batadv_softif_vlan *vlan;
     struct net_device *in_dev = NULL;
     struct batadv_hard_iface *in_hardif = NULL;
     struct hlist_head *head;
     struct batadv_tt_orig_list_entry *orig_entry;
     int hash_added, table_size, packet_size_max;
     bool ret = false;
     bool roamed_back = false;
     u8 remote_flags;
     u32 match_mark;
 
     if (ifindex != BATADV_NULL_IFINDEX)
         in_dev = dev_get_by_index(net, ifindex);
 
     if (in_dev)
         in_hardif = batadv_hardif_get_by_netdev(in_dev);
 
     tt_local = batadv_tt_local_hash_find(bat_priv, addr, vid);
 
     if (!is_multicast_ether_addr(addr))
         tt_global = batadv_tt_global_hash_find(bat_priv, addr, vid);
 
     if (tt_local) {
         tt_local->last_seen = jiffies;
         if (tt_local->common.flags & BATADV_TT_CLIENT_PENDING) {
             batadv_dbg(BATADV_DBG_TT, bat_priv,
                    "Re-adding pending client %pM (vid: %d)\n",
                    addr, batadv_print_vid(vid));
             /* whatever the reason why the PENDING flag was set,
              * this is a client which was enqueued to be removed in
              * this orig_interval. Since it popped up again, the
              * flag can be reset like it was never enqueued
              */
             tt_local->common.flags &= ~BATADV_TT_CLIENT_PENDING;
             goto add_event;
         }
 
         if (tt_local->common.flags & BATADV_TT_CLIENT_ROAM) {
             batadv_dbg(BATADV_DBG_TT, bat_priv,
                    "Roaming client %pM (vid: %d) came back to its original location\n",
                    addr, batadv_print_vid(vid));
             /* the ROAM flag is set because this client roamed away
              * and the node got a roaming_advertisement message. Now
              * that the client popped up again at its original
              * location such flag can be unset
              */
             tt_local->common.flags &= ~BATADV_TT_CLIENT_ROAM;
             roamed_back = true;
         }
         goto check_roaming;
     }
 
     /* Ignore the client if we cannot send it in a full table response. */
     table_size = batadv_tt_local_table_transmit_size(bat_priv);
     table_size += batadv_tt_len(1);
     packet_size_max = atomic_read(&bat_priv->packet_size_max);
     if (table_size > packet_size_max) {
         net_ratelimited_function(batadv_info, soft_iface,
                      "Local translation table size (%i) exceeds maximum packet size (%i); Ignoring new local tt entry: %pM\n",
                      table_size, packet_size_max, addr);
         goto out;
     }
 
     tt_local = kmem_cache_alloc(batadv_tl_cache, GFP_ATOMIC);
     if (!tt_local)
         goto out;
 
     /* increase the refcounter of the related vlan */
     vlan = batadv_softif_vlan_get(bat_priv, vid);
     if (!vlan) {
         net_ratelimited_function(batadv_info, soft_iface,
                      "adding TT local entry %pM to non-existent VLAN %d\n",
                      addr, batadv_print_vid(vid));
         kmem_cache_free(batadv_tl_cache, tt_local);
         tt_local = NULL;
         goto out;
     }
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Creating new local tt entry: %pM (vid: %d, ttvn: %d)\n",
            addr, batadv_print_vid(vid),
            (u8)atomic_read(&bat_priv->tt.vn));
 
     ether_addr_copy(tt_local->common.addr, addr);
     /* The local entry has to be marked as NEW to avoid to send it in
      * a full table response going out before the next ttvn increment
      * (consistency check)
      */
     tt_local->common.flags = BATADV_TT_CLIENT_NEW;
     tt_local->common.vid = vid;
     if (batadv_is_wifi_hardif(in_hardif))
         tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
     kref_init(&tt_local->common.refcount);
     tt_local->last_seen = jiffies;
     tt_local->common.added_at = tt_local->last_seen;
     tt_local->vlan = vlan;
 
     /* the batman interface mac and multicast addresses should never be
      * purged
      */
     if (batadv_compare_eth(addr, soft_iface->dev_addr) ||
         is_multicast_ether_addr(addr))
         tt_local->common.flags |= BATADV_TT_CLIENT_NOPURGE;
 
     kref_get(&tt_local->common.refcount);
     hash_added = batadv_hash_add(bat_priv->tt.local_hash, batadv_compare_tt,
                      batadv_choose_tt, &tt_local->common,
                      &tt_local->common.hash_entry);
 
     if (unlikely(hash_added != 0)) {
         /* remove the reference for the hash */
         batadv_tt_local_entry_put(tt_local);
         goto out;
     }
 
 add_event:
     batadv_tt_local_event(bat_priv, tt_local, BATADV_NO_FLAGS);
 
 check_roaming:
     /* Check whether it is a roaming, but don't do anything if the roaming
      * process has already been handled
      */
     if (tt_global && !(tt_global->common.flags & BATADV_TT_CLIENT_ROAM)) {
         /* These node are probably going to update their tt table */
         head = &tt_global->orig_list;
         rcu_read_lock();
         hlist_for_each_entry_rcu(orig_entry, head, list) {
             batadv_send_roam_adv(bat_priv, tt_global->common.addr,
                          tt_global->common.vid,
                          orig_entry->orig_node);
         }
         rcu_read_unlock();
         if (roamed_back) {
             batadv_tt_global_free(bat_priv, tt_global,
                           "Roaming canceled");
             tt_global = NULL;
         } else {
             /* The global entry has to be marked as ROAMING and
              * has to be kept for consistency purpose
              */
             tt_global->common.flags |= BATADV_TT_CLIENT_ROAM;
             tt_global->roam_at = jiffies;
         }
     }
 
     /* store the current remote flags before altering them. This helps
      * understanding is flags are changing or not
      */
     remote_flags = tt_local->common.flags & BATADV_TT_REMOTE_MASK;
 
     if (batadv_is_wifi_hardif(in_hardif))
         tt_local->common.flags |= BATADV_TT_CLIENT_WIFI;
     else
         tt_local->common.flags &= ~BATADV_TT_CLIENT_WIFI;
 
     /* check the mark in the skb: if it's equal to the configured
      * isolation_mark, it means the packet is coming from an isolated
      * non-mesh client
      */
     match_mark = (mark & bat_priv->isolation_mark_mask);
     if (bat_priv->isolation_mark_mask &&
         match_mark == bat_priv->isolation_mark)
         tt_local->common.flags |= BATADV_TT_CLIENT_ISOLA;
     else
         tt_local->common.flags &= ~BATADV_TT_CLIENT_ISOLA;
 
     /* if any "dynamic" flag has been modified, resend an ADD event for this
      * entry so that all the nodes can get the new flags
      */
     if (remote_flags ^ (tt_local->common.flags & BATADV_TT_REMOTE_MASK))
         batadv_tt_local_event(bat_priv, tt_local, BATADV_NO_FLAGS);
 
     ret = true;
 out:
     batadv_hardif_put(in_hardif);
     dev_put(in_dev);
     batadv_tt_local_entry_put(tt_local);
     batadv_tt_global_entry_put(tt_global);
     return ret;
 }
 
 /**
  * batadv_tt_prepare_tvlv_global_data() - prepare the TVLV TT header to send
  *  within a TT Response directed to another node
  * @orig_node: originator for which the TT data has to be prepared
  * @tt_data: uninitialised pointer to the address of the TVLV buffer
  * @tt_change: uninitialised pointer to the address of the area where the TT
  *  changed can be stored
  * @tt_len: pointer to the length to reserve to the tt_change. if -1 this
  *  function reserves the amount of space needed to send the entire global TT
  *  table. In case of success the value is updated with the real amount of
  *  reserved bytes
  * Allocate the needed amount of memory for the entire TT TVLV and write its
  * header made up of one tvlv_tt_data object and a series of tvlv_tt_vlan_data
  * objects, one per active VLAN served by the originator node.
  *
  * Return: the size of the allocated buffer or 0 in case of failure.
  */
 static u16
 batadv_tt_prepare_tvlv_global_data(struct batadv_orig_node *orig_node,
                    struct batadv_tvlv_tt_data **tt_data,
                    struct batadv_tvlv_tt_change **tt_change,
                    s32 *tt_len)
 {
     u16 num_vlan = 0;
     u16 num_entries = 0;
     u16 change_offset;
     u16 tvlv_len;
     struct batadv_tvlv_tt_vlan_data *tt_vlan;
     struct batadv_orig_node_vlan *vlan;
     u8 *tt_change_ptr;
 
     spin_lock_bh(&orig_node->vlan_list_lock);
     hlist_for_each_entry(vlan, &orig_node->vlan_list, list) {
         num_vlan++;
         num_entries += atomic_read(&vlan->tt.num_entries);
     }
 
     change_offset = sizeof(**tt_data);
     change_offset += num_vlan * sizeof(*tt_vlan);
 
     /* if tt_len is negative, allocate the space needed by the full table */
     if (*tt_len < 0)
         *tt_len = batadv_tt_len(num_entries);
 
     tvlv_len = *tt_len;
     tvlv_len += change_offset;
 
     *tt_data = kmalloc(tvlv_len, GFP_ATOMIC);
     if (!*tt_data) {
         *tt_len = 0;
         goto out;
     }
 
     (*tt_data)->flags = BATADV_NO_FLAGS;
     (*tt_data)->ttvn = atomic_read(&orig_node->last_ttvn);
     (*tt_data)->num_vlan = htons(num_vlan);
 
     tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(*tt_data + 1);
     hlist_for_each_entry(vlan, &orig_node->vlan_list, list) {
         tt_vlan->vid = htons(vlan->vid);
         tt_vlan->crc = htonl(vlan->tt.crc);
         tt_vlan->reserved = 0;
 
         tt_vlan++;
     }
 
     tt_change_ptr = (u8 *)*tt_data + change_offset;
     *tt_change = (struct batadv_tvlv_tt_change *)tt_change_ptr;
 
 out:
     spin_unlock_bh(&orig_node->vlan_list_lock);
     return tvlv_len;
 }
 
 /**
  * batadv_tt_prepare_tvlv_local_data() - allocate and prepare the TT TVLV for
  *  this node
  * @bat_priv: the bat priv with all the soft interface information
  * @tt_data: uninitialised pointer to the address of the TVLV buffer
  * @tt_change: uninitialised pointer to the address of the area where the TT
  *  changes can be stored
  * @tt_len: pointer to the length to reserve to the tt_change. if -1 this
  *  function reserves the amount of space needed to send the entire local TT
  *  table. In case of success the value is updated with the real amount of
  *  reserved bytes
  *
  * Allocate the needed amount of memory for the entire TT TVLV and write its
  * header made up by one tvlv_tt_data object and a series of tvlv_tt_vlan_data
  * objects, one per active VLAN.
  *
  * Return: the size of the allocated buffer or 0 in case of failure.
  */
 static u16
 batadv_tt_prepare_tvlv_local_data(struct batadv_priv *bat_priv,
                   struct batadv_tvlv_tt_data **tt_data,
                   struct batadv_tvlv_tt_change **tt_change,
                   s32 *tt_len)
 {
     struct batadv_tvlv_tt_vlan_data *tt_vlan;
     struct batadv_softif_vlan *vlan;
     u16 num_vlan = 0;
     u16 vlan_entries = 0;
     u16 total_entries = 0;
     u16 tvlv_len;
     u8 *tt_change_ptr;
     int change_offset;
 
     spin_lock_bh(&bat_priv->softif_vlan_list_lock);
     hlist_for_each_entry(vlan, &bat_priv->softif_vlan_list, list) {
         vlan_entries = atomic_read(&vlan->tt.num_entries);
         if (vlan_entries < 1)
             continue;
 
         num_vlan++;
         total_entries += vlan_entries;
     }
 
     change_offset = sizeof(**tt_data);
     change_offset += num_vlan * sizeof(*tt_vlan);
 
     /* if tt_len is negative, allocate the space needed by the full table */
     if (*tt_len < 0)
         *tt_len = batadv_tt_len(total_entries);
 
     tvlv_len = *tt_len;
     tvlv_len += change_offset;
 
     *tt_data = kmalloc(tvlv_len, GFP_ATOMIC);
     if (!*tt_data) {
         tvlv_len = 0;
         goto out;
     }
 
     (*tt_data)->flags = BATADV_NO_FLAGS;
     (*tt_data)->ttvn = atomic_read(&bat_priv->tt.vn);
     (*tt_data)->num_vlan = htons(num_vlan);
 
     tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(*tt_data + 1);
     hlist_for_each_entry(vlan, &bat_priv->softif_vlan_list, list) {
         vlan_entries = atomic_read(&vlan->tt.num_entries);
         if (vlan_entries < 1)
             continue;
 
         tt_vlan->vid = htons(vlan->vid);
         tt_vlan->crc = htonl(vlan->tt.crc);
         tt_vlan->reserved = 0;
 
         tt_vlan++;
     }
 
     tt_change_ptr = (u8 *)*tt_data + change_offset;
     *tt_change = (struct batadv_tvlv_tt_change *)tt_change_ptr;
 
 out:
     spin_unlock_bh(&bat_priv->softif_vlan_list_lock);
     return tvlv_len;
 }
 
 /**
  * batadv_tt_tvlv_container_update() - update the translation table tvlv
  *  container after local tt changes have been committed
  * @bat_priv: the bat priv with all the soft interface information
  */
 static void batadv_tt_tvlv_container_update(struct batadv_priv *bat_priv)
 {
     struct batadv_tt_change_node *entry, *safe;
     struct batadv_tvlv_tt_data *tt_data;
     struct batadv_tvlv_tt_change *tt_change;
     int tt_diff_len, tt_change_len = 0;
     int tt_diff_entries_num = 0;
     int tt_diff_entries_count = 0;
     u16 tvlv_len;
 
     tt_diff_entries_num = atomic_read(&bat_priv->tt.local_changes);
     tt_diff_len = batadv_tt_len(tt_diff_entries_num);
 
     /* if we have too many changes for one packet don't send any
      * and wait for the tt table request which will be fragmented
      */
     if (tt_diff_len > bat_priv->soft_iface->mtu)
         tt_diff_len = 0;
 
     tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv, &tt_data,
                              &tt_change, &tt_diff_len);
     if (!tvlv_len)
         return;
 
     tt_data->flags = BATADV_TT_OGM_DIFF;
 
     if (tt_diff_len == 0)
         goto container_register;
 
     spin_lock_bh(&bat_priv->tt.changes_list_lock);
     atomic_set(&bat_priv->tt.local_changes, 0);
 
     list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
                  list) {
         if (tt_diff_entries_count < tt_diff_entries_num) {
             memcpy(tt_change + tt_diff_entries_count,
                    &entry->change,
                    sizeof(struct batadv_tvlv_tt_change));
             tt_diff_entries_count++;
         }
         list_del(&entry->list);
         kmem_cache_free(batadv_tt_change_cache, entry);
     }
     spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 
     /* Keep the buffer for possible tt_request */
     spin_lock_bh(&bat_priv->tt.last_changeset_lock);
     kfree(bat_priv->tt.last_changeset);
     bat_priv->tt.last_changeset_len = 0;
     bat_priv->tt.last_changeset = NULL;
     tt_change_len = batadv_tt_len(tt_diff_entries_count);
     /* check whether this new OGM has no changes due to size problems */
     if (tt_diff_entries_count > 0) {
         /* if kmalloc() fails we will reply with the full table
          * instead of providing the diff
          */
         bat_priv->tt.last_changeset = kzalloc(tt_diff_len, GFP_ATOMIC);
         if (bat_priv->tt.last_changeset) {
             memcpy(bat_priv->tt.last_changeset,
                    tt_change, tt_change_len);
             bat_priv->tt.last_changeset_len = tt_diff_len;
         }
     }
     spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
 
 container_register:
     batadv_tvlv_container_register(bat_priv, BATADV_TVLV_TT, 1, tt_data,
                        tvlv_len);
     kfree(tt_data);
 }
 
 /**
  * batadv_tt_local_dump_entry() - Dump one TT local entry into a message
  * @msg :Netlink message to dump into
  * @portid: Port making netlink request
  * @cb: Control block containing additional options
  * @bat_priv: The bat priv with all the soft interface information
  * @common: tt local & tt global common data
  *
  * Return: Error code, or 0 on success
  */
 static int
 batadv_tt_local_dump_entry(struct sk_buff *msg, u32 portid,
                struct netlink_callback *cb,
                struct batadv_priv *bat_priv,
                struct batadv_tt_common_entry *common)
 {
     void *hdr;
     struct batadv_softif_vlan *vlan;
     struct batadv_tt_local_entry *local;
     unsigned int last_seen_msecs;
     u32 crc;
 
     local = container_of(common, struct batadv_tt_local_entry, common);
     last_seen_msecs = jiffies_to_msecs(jiffies - local->last_seen);
 
     vlan = batadv_softif_vlan_get(bat_priv, common->vid);
     if (!vlan)
         return 0;
 
     crc = vlan->tt.crc;
 
     batadv_softif_vlan_put(vlan);
 
     hdr = genlmsg_put(msg, portid, cb->nlh->nlmsg_seq,
               &batadv_netlink_family,  NLM_F_MULTI,
               BATADV_CMD_GET_TRANSTABLE_LOCAL);
     if (!hdr)
         return -ENOBUFS;
 
     genl_dump_check_consistent(cb, hdr);
 
     if (nla_put(msg, BATADV_ATTR_TT_ADDRESS, ETH_ALEN, common->addr) ||
         nla_put_u32(msg, BATADV_ATTR_TT_CRC32, crc) ||
         nla_put_u16(msg, BATADV_ATTR_TT_VID, common->vid) ||
         nla_put_u32(msg, BATADV_ATTR_TT_FLAGS, common->flags))
         goto nla_put_failure;
 
     if (!(common->flags & BATADV_TT_CLIENT_NOPURGE) &&
         nla_put_u32(msg, BATADV_ATTR_LAST_SEEN_MSECS, last_seen_msecs))
         goto nla_put_failure;
 
     genlmsg_end(msg, hdr);
     return 0;
 
  nla_put_failure:
     genlmsg_cancel(msg, hdr);
     return -EMSGSIZE;
 }
 
 /**
  * batadv_tt_local_dump_bucket() - Dump one TT local bucket into a message
  * @msg: Netlink message to dump into
  * @portid: Port making netlink request
  * @cb: Control block containing additional options
  * @bat_priv: The bat priv with all the soft interface information
  * @hash: hash to dump
  * @bucket: bucket index to dump
  * @idx_s: Number of entries to skip
  *
  * Return: Error code, or 0 on success
  */
 static int
 batadv_tt_local_dump_bucket(struct sk_buff *msg, u32 portid,
                 struct netlink_callback *cb,
                 struct batadv_priv *bat_priv,
                 struct batadv_hashtable *hash, unsigned int bucket,
                 int *idx_s)
 {
     struct batadv_tt_common_entry *common;
     int idx = 0;
 
     spin_lock_bh(&hash->list_locks[bucket]);
     cb->seq = atomic_read(&hash->generation) << 1 | 1;
 
     hlist_for_each_entry(common, &hash->table[bucket], hash_entry) {
         if (idx++ < *idx_s)
             continue;
 
         if (batadv_tt_local_dump_entry(msg, portid, cb, bat_priv,
                            common)) {
             spin_unlock_bh(&hash->list_locks[bucket]);
             *idx_s = idx - 1;
             return -EMSGSIZE;
         }
     }
     spin_unlock_bh(&hash->list_locks[bucket]);
 
     *idx_s = 0;
     return 0;
 }
 
 /**
  * batadv_tt_local_dump() - Dump TT local entries into a message
  * @msg: Netlink message to dump into
  * @cb: Parameters from query
  *
  * Return: Error code, or 0 on success
  */
 int batadv_tt_local_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
     struct net *net = sock_net(cb->skb->sk);
     struct net_device *soft_iface;
     struct batadv_priv *bat_priv;
     struct batadv_hard_iface *primary_if = NULL;
     struct batadv_hashtable *hash;
     int ret;
     int ifindex;
     int bucket = cb->args[0];
     int idx = cb->args[1];
     int portid = NETLINK_CB(cb->skb).portid;
 
     ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
     if (!ifindex)
         return -EINVAL;
 
     soft_iface = dev_get_by_index(net, ifindex);
     if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
         ret = -ENODEV;
         goto out;
     }
 
     bat_priv = netdev_priv(soft_iface);
 
     primary_if = batadv_primary_if_get_selected(bat_priv);
     if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
         ret = -ENOENT;
         goto out;
     }
 
     hash = bat_priv->tt.local_hash;
 
     while (bucket < hash->size) {
         if (batadv_tt_local_dump_bucket(msg, portid, cb, bat_priv,
                         hash, bucket, &idx))
             break;
 
         bucket++;
     }
 
     ret = msg->len;
 
  out:
     batadv_hardif_put(primary_if);
     dev_put(soft_iface);
 
     cb->args[0] = bucket;
     cb->args[1] = idx;
 
     return ret;
 }
 
 static void
 batadv_tt_local_set_pending(struct batadv_priv *bat_priv,
                 struct batadv_tt_local_entry *tt_local_entry,
                 u16 flags, const char *message)
 {
     batadv_tt_local_event(bat_priv, tt_local_entry, flags);
 
     /* The local client has to be marked as "pending to be removed" but has
      * to be kept in the table in order to send it in a full table
      * response issued before the net ttvn increment (consistency check)
      */
     tt_local_entry->common.flags |= BATADV_TT_CLIENT_PENDING;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Local tt entry (%pM, vid: %d) pending to be removed: %s\n",
            tt_local_entry->common.addr,
            batadv_print_vid(tt_local_entry->common.vid), message);
 }
 
 /**
  * batadv_tt_local_remove() - logically remove an entry from the local table
  * @bat_priv: the bat priv with all the soft interface information
  * @addr: the MAC address of the client to remove
  * @vid: VLAN identifier
  * @message: message to append to the log on deletion
  * @roaming: true if the deletion is due to a roaming event
  *
  * Return: the flags assigned to the local entry before being deleted
  */
 u16 batadv_tt_local_remove(struct batadv_priv *bat_priv, const u8 *addr,
                unsigned short vid, const char *message,
                bool roaming)
 {
     struct batadv_tt_local_entry *tt_removed_entry;
     struct batadv_tt_local_entry *tt_local_entry;
     u16 flags, curr_flags = BATADV_NO_FLAGS;
     struct hlist_node *tt_removed_node;
 
     tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
     if (!tt_local_entry)
         goto out;
 
     curr_flags = tt_local_entry->common.flags;
 
     flags = BATADV_TT_CLIENT_DEL;
     /* if this global entry addition is due to a roaming, the node has to
      * mark the local entry as "roamed" in order to correctly reroute
      * packets later
      */
     if (roaming) {
         flags |= BATADV_TT_CLIENT_ROAM;
         /* mark the local client as ROAMed */
         tt_local_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
     }
 
     if (!(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW)) {
         batadv_tt_local_set_pending(bat_priv, tt_local_entry, flags,
                         message);
         goto out;
     }
     /* if this client has been added right now, it is possible to
      * immediately purge it
      */
     batadv_tt_local_event(bat_priv, tt_local_entry, BATADV_TT_CLIENT_DEL);
 
     tt_removed_node = batadv_hash_remove(bat_priv->tt.local_hash,
                          batadv_compare_tt,
                          batadv_choose_tt,
                          &tt_local_entry->common);
     if (!tt_removed_node)
         goto out;
 
     /* drop reference of remove hash entry */
     tt_removed_entry = hlist_entry(tt_removed_node,
                        struct batadv_tt_local_entry,
                        common.hash_entry);
     batadv_tt_local_entry_put(tt_removed_entry);
 
 out:
     batadv_tt_local_entry_put(tt_local_entry);
 
     return curr_flags;
 }
 
 /**
  * batadv_tt_local_purge_list() - purge inactive tt local entries
  * @bat_priv: the bat priv with all the soft interface information
  * @head: pointer to the list containing the local tt entries
  * @timeout: parameter deciding whether a given tt local entry is considered
  *  inactive or not
  */
 static void batadv_tt_local_purge_list(struct batadv_priv *bat_priv,
                        struct hlist_head *head,
                        int timeout)
 {
     struct batadv_tt_local_entry *tt_local_entry;
     struct batadv_tt_common_entry *tt_common_entry;
     struct hlist_node *node_tmp;
 
     hlist_for_each_entry_safe(tt_common_entry, node_tmp, head,
                   hash_entry) {
         tt_local_entry = container_of(tt_common_entry,
                           struct batadv_tt_local_entry,
                           common);
         if (tt_local_entry->common.flags & BATADV_TT_CLIENT_NOPURGE)
             continue;
 
         /* entry already marked for deletion */
         if (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING)
             continue;
 
         if (!batadv_has_timed_out(tt_local_entry->last_seen, timeout))
             continue;
 
         batadv_tt_local_set_pending(bat_priv, tt_local_entry,
                         BATADV_TT_CLIENT_DEL, "timed out");
     }
 }
 
 /**
  * batadv_tt_local_purge() - purge inactive tt local entries
  * @bat_priv: the bat priv with all the soft interface information
  * @timeout: parameter deciding whether a given tt local entry is considered
  *  inactive or not
  */
 static void batadv_tt_local_purge(struct batadv_priv *bat_priv,
                   int timeout)
 {
     struct batadv_hashtable *hash = bat_priv->tt.local_hash;
     struct hlist_head *head;
     spinlock_t *list_lock; /* protects write access to the hash lists */
     u32 i;
 
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
         list_lock = &hash->list_locks[i];
 
         spin_lock_bh(list_lock);
         batadv_tt_local_purge_list(bat_priv, head, timeout);
         spin_unlock_bh(list_lock);
     }
 }
 
 static void batadv_tt_local_table_free(struct batadv_priv *bat_priv)
 {
     struct batadv_hashtable *hash;
     spinlock_t *list_lock; /* protects write access to the hash lists */
     struct batadv_tt_common_entry *tt_common_entry;
     struct batadv_tt_local_entry *tt_local;
     struct hlist_node *node_tmp;
     struct hlist_head *head;
     u32 i;
 
     if (!bat_priv->tt.local_hash)
         return;
 
     hash = bat_priv->tt.local_hash;
 
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
         list_lock = &hash->list_locks[i];
 
         spin_lock_bh(list_lock);
         hlist_for_each_entry_safe(tt_common_entry, node_tmp,
                       head, hash_entry) {
             hlist_del_rcu(&tt_common_entry->hash_entry);
             tt_local = container_of(tt_common_entry,
                         struct batadv_tt_local_entry,
                         common);
 
             batadv_tt_local_entry_put(tt_local);
         }
         spin_unlock_bh(list_lock);
     }
 
     batadv_hash_destroy(hash);
 
     bat_priv->tt.local_hash = NULL;
 }
 
 static int batadv_tt_global_init(struct batadv_priv *bat_priv)
 {
     if (bat_priv->tt.global_hash)
         return 0;
 
     bat_priv->tt.global_hash = batadv_hash_new(1024);
 
     if (!bat_priv->tt.global_hash)
         return -ENOMEM;
 
     batadv_hash_set_lock_class(bat_priv->tt.global_hash,
                    &batadv_tt_global_hash_lock_class_key);
 
     return 0;
 }
 
 static void batadv_tt_changes_list_free(struct batadv_priv *bat_priv)
 {
     struct batadv_tt_change_node *entry, *safe;
 
     spin_lock_bh(&bat_priv->tt.changes_list_lock);
 
     list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
                  list) {
         list_del(&entry->list);
         kmem_cache_free(batadv_tt_change_cache, entry);
     }
 
     atomic_set(&bat_priv->tt.local_changes, 0);
     spin_unlock_bh(&bat_priv->tt.changes_list_lock);
 }
 
 /**
  * batadv_tt_global_orig_entry_find() - find a TT orig_list_entry
  * @entry: the TT global entry where the orig_list_entry has to be
  *  extracted from
  * @orig_node: the originator for which the orig_list_entry has to be found
  *
  * retrieve the orig_tt_list_entry belonging to orig_node from the
  * batadv_tt_global_entry list
  *
  * Return: it with an increased refcounter, NULL if not found
  */
 static struct batadv_tt_orig_list_entry *
 batadv_tt_global_orig_entry_find(const struct batadv_tt_global_entry *entry,
                  const struct batadv_orig_node *orig_node)
 {
     struct batadv_tt_orig_list_entry *tmp_orig_entry, *orig_entry = NULL;
     const struct hlist_head *head;
 
     rcu_read_lock();
     head = &entry->orig_list;
     hlist_for_each_entry_rcu(tmp_orig_entry, head, list) {
         if (tmp_orig_entry->orig_node != orig_node)
             continue;
         if (!kref_get_unless_zero(&tmp_orig_entry->refcount))
             continue;
 
         orig_entry = tmp_orig_entry;
         break;
     }
     rcu_read_unlock();
 
     return orig_entry;
 }
 
 /**
  * batadv_tt_global_entry_has_orig() - check if a TT global entry is also
  *  handled by a given originator
  * @entry: the TT global entry to check
  * @orig_node: the originator to search in the list
  * @flags: a pointer to store TT flags for the given @entry received
  *  from @orig_node
  *
  * find out if an orig_node is already in the list of a tt_global_entry.
  *
  * Return: true if found, false otherwise
  */
 static bool
 batadv_tt_global_entry_has_orig(const struct batadv_tt_global_entry *entry,
                 const struct batadv_orig_node *orig_node,
                 u8 *flags)
 {
     struct batadv_tt_orig_list_entry *orig_entry;
     bool found = false;
 
     orig_entry = batadv_tt_global_orig_entry_find(entry, orig_node);
     if (orig_entry) {
         found = true;
 
         if (flags)
             *flags = orig_entry->flags;
 
         batadv_tt_orig_list_entry_put(orig_entry);
     }
 
     return found;
 }
 
 /**
  * batadv_tt_global_sync_flags() - update TT sync flags
  * @tt_global: the TT global entry to update sync flags in
  *
  * Updates the sync flag bits in the tt_global flag attribute with a logical
  * OR of all sync flags from any of its TT orig entries.
  */
 static void
 batadv_tt_global_sync_flags(struct batadv_tt_global_entry *tt_global)
 {
     struct batadv_tt_orig_list_entry *orig_entry;
     const struct hlist_head *head;
     u16 flags = BATADV_NO_FLAGS;
 
     rcu_read_lock();
     head = &tt_global->orig_list;
     hlist_for_each_entry_rcu(orig_entry, head, list)
         flags |= orig_entry->flags;
     rcu_read_unlock();
 
     flags |= tt_global->common.flags & (~BATADV_TT_SYNC_MASK);
     tt_global->common.flags = flags;
 }
 
 /**
  * batadv_tt_global_orig_entry_add() - add or update a TT orig entry
  * @tt_global: the TT global entry to add an orig entry in
  * @orig_node: the originator to add an orig entry for
  * @ttvn: translation table version number of this changeset
  * @flags: TT sync flags
  */
 static void
 batadv_tt_global_orig_entry_add(struct batadv_tt_global_entry *tt_global,
                 struct batadv_orig_node *orig_node, int ttvn,
                 u8 flags)
 {
     struct batadv_tt_orig_list_entry *orig_entry;
 
     spin_lock_bh(&tt_global->list_lock);
 
     orig_entry = batadv_tt_global_orig_entry_find(tt_global, orig_node);
     if (orig_entry) {
         /* refresh the ttvn: the current value could be a bogus one that
          * was added during a "temporary client detection"
          */
         orig_entry->ttvn = ttvn;
         orig_entry->flags = flags;
         goto sync_flags;
     }
 
     orig_entry = kmem_cache_zalloc(batadv_tt_orig_cache, GFP_ATOMIC);
     if (!orig_entry)
         goto out;
 
     INIT_HLIST_NODE(&orig_entry->list);
     kref_get(&orig_node->refcount);
     batadv_tt_global_size_inc(orig_node, tt_global->common.vid);
     orig_entry->orig_node = orig_node;
     orig_entry->ttvn = ttvn;
     orig_entry->flags = flags;
     kref_init(&orig_entry->refcount);
 
     kref_get(&orig_entry->refcount);
     hlist_add_head_rcu(&orig_entry->list,
                &tt_global->orig_list);
     atomic_inc(&tt_global->orig_list_count);
 
 sync_flags:
     batadv_tt_global_sync_flags(tt_global);
 out:
     batadv_tt_orig_list_entry_put(orig_entry);
 
     spin_unlock_bh(&tt_global->list_lock);
 }
 
 /**
  * batadv_tt_global_add() - add a new TT global entry or update an existing one
  * @bat_priv: the bat priv with all the soft interface information
  * @orig_node: the originator announcing the client
  * @tt_addr: the mac address of the non-mesh client
  * @vid: VLAN identifier
  * @flags: TT flags that have to be set for this non-mesh client
  * @ttvn: the tt version number ever announcing this non-mesh client
  *
  * Add a new TT global entry for the given originator. If the entry already
  * exists add a new reference to the given originator (a global entry can have
  * references to multiple originators) and adjust the flags attribute to reflect
  * the function argument.
  * If a TT local entry exists for this non-mesh client remove it.
  *
  * The caller must hold the orig_node refcount.
  *
  * Return: true if the new entry has been added, false otherwise
  */
 static bool batadv_tt_global_add(struct batadv_priv *bat_priv,
                  struct batadv_orig_node *orig_node,
                  const unsigned char *tt_addr,
                  unsigned short vid, u16 flags, u8 ttvn)
 {
     struct batadv_tt_global_entry *tt_global_entry;
     struct batadv_tt_local_entry *tt_local_entry;
     bool ret = false;
     int hash_added;
     struct batadv_tt_common_entry *common;
     u16 local_flags;
 
     /* ignore global entries from backbone nodes */
     if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig, vid))
         return true;
 
     tt_global_entry = batadv_tt_global_hash_find(bat_priv, tt_addr, vid);
     tt_local_entry = batadv_tt_local_hash_find(bat_priv, tt_addr, vid);
 
     /* if the node already has a local client for this entry, it has to wait
      * for a roaming advertisement instead of manually messing up the global
      * table
      */
     if ((flags & BATADV_TT_CLIENT_TEMP) && tt_local_entry &&
         !(tt_local_entry->common.flags & BATADV_TT_CLIENT_NEW))
         goto out;
 
     if (!tt_global_entry) {
         tt_global_entry = kmem_cache_zalloc(batadv_tg_cache,
                             GFP_ATOMIC);
         if (!tt_global_entry)
             goto out;
 
         common = &tt_global_entry->common;
         ether_addr_copy(common->addr, tt_addr);
         common->vid = vid;
 
         if (!is_multicast_ether_addr(common->addr))
             common->flags = flags & (~BATADV_TT_SYNC_MASK);
 
         tt_global_entry->roam_at = 0;
         /* node must store current time in case of roaming. This is
          * needed to purge this entry out on timeout (if nobody claims
          * it)
          */
         if (flags & BATADV_TT_CLIENT_ROAM)
             tt_global_entry->roam_at = jiffies;
         kref_init(&common->refcount);
         common->added_at = jiffies;
 
         INIT_HLIST_HEAD(&tt_global_entry->orig_list);
         atomic_set(&tt_global_entry->orig_list_count, 0);
         spin_lock_init(&tt_global_entry->list_lock);
 
         kref_get(&common->refcount);
         hash_added = batadv_hash_add(bat_priv->tt.global_hash,
                          batadv_compare_tt,
                          batadv_choose_tt, common,
                          &common->hash_entry);
 
         if (unlikely(hash_added != 0)) {
             /* remove the reference for the hash */
             batadv_tt_global_entry_put(tt_global_entry);
             goto out_remove;
         }
     } else {
         common = &tt_global_entry->common;
         /* If there is already a global entry, we can use this one for
          * our processing.
          * But if we are trying to add a temporary client then here are
          * two options at this point:
          * 1) the global client is not a temporary client: the global
          *    client has to be left as it is, temporary information
          *    should never override any already known client state
          * 2) the global client is a temporary client: purge the
          *    originator list and add the new one orig_entry
          */
         if (flags & BATADV_TT_CLIENT_TEMP) {
             if (!(common->flags & BATADV_TT_CLIENT_TEMP))
                 goto out;
             if (batadv_tt_global_entry_has_orig(tt_global_entry,
                                 orig_node, NULL))
                 goto out_remove;
             batadv_tt_global_del_orig_list(tt_global_entry);
             goto add_orig_entry;
         }
 
         /* if the client was temporary added before receiving the first
          * OGM announcing it, we have to clear the TEMP flag. Also,
          * remove the previous temporary orig node and re-add it
          * if required. If the orig entry changed, the new one which
          * is a non-temporary entry is preferred.
          */
         if (common->flags & BATADV_TT_CLIENT_TEMP) {
             batadv_tt_global_del_orig_list(tt_global_entry);
             common->flags &= ~BATADV_TT_CLIENT_TEMP;
         }
 
         /* the change can carry possible "attribute" flags like the
          * TT_CLIENT_TEMP, therefore they have to be copied in the
          * client entry
          */
         if (!is_multicast_ether_addr(common->addr))
             common->flags |= flags & (~BATADV_TT_SYNC_MASK);
 
         /* If there is the BATADV_TT_CLIENT_ROAM flag set, there is only
          * one originator left in the list and we previously received a
          * delete + roaming change for this originator.
          *
          * We should first delete the old originator before adding the
          * new one.
          */
         if (common->flags & BATADV_TT_CLIENT_ROAM) {
             batadv_tt_global_del_orig_list(tt_global_entry);
             common->flags &= ~BATADV_TT_CLIENT_ROAM;
             tt_global_entry->roam_at = 0;
         }
     }
 add_orig_entry:
     /* add the new orig_entry (if needed) or update it */
     batadv_tt_global_orig_entry_add(tt_global_entry, orig_node, ttvn,
                     flags & BATADV_TT_SYNC_MASK);
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Creating new global tt entry: %pM (vid: %d, via %pM)\n",
            common->addr, batadv_print_vid(common->vid),
            orig_node->orig);
     ret = true;
 
 out_remove:
     /* Do not remove multicast addresses from the local hash on
      * global additions
      */
     if (is_multicast_ether_addr(tt_addr))
         goto out;
 
     /* remove address from local hash if present */
     local_flags = batadv_tt_local_remove(bat_priv, tt_addr, vid,
                          "global tt received",
                          flags & BATADV_TT_CLIENT_ROAM);
     tt_global_entry->common.flags |= local_flags & BATADV_TT_CLIENT_WIFI;
 
     if (!(flags & BATADV_TT_CLIENT_ROAM))
         /* this is a normal global add. Therefore the client is not in a
          * roaming state anymore.
          */
         tt_global_entry->common.flags &= ~BATADV_TT_CLIENT_ROAM;
 
 out:
     batadv_tt_global_entry_put(tt_global_entry);
     batadv_tt_local_entry_put(tt_local_entry);
     return ret;
 }
 
 /**
  * batadv_transtable_best_orig() - Get best originator list entry from tt entry
  * @bat_priv: the bat priv with all the soft interface information
  * @tt_global_entry: global translation table entry to be analyzed
  *
  * This function assumes the caller holds rcu_read_lock().
  * Return: best originator list entry or NULL on errors.
  */
 static struct batadv_tt_orig_list_entry *
 batadv_transtable_best_orig(struct batadv_priv *bat_priv,
                 struct batadv_tt_global_entry *tt_global_entry)
 {
     struct batadv_neigh_node *router, *best_router = NULL;
     struct batadv_algo_ops *bao = bat_priv->algo_ops;
     struct hlist_head *head;
     struct batadv_tt_orig_list_entry *orig_entry, *best_entry = NULL;
 
     head = &tt_global_entry->orig_list;
     hlist_for_each_entry_rcu(orig_entry, head, list) {
         router = batadv_orig_router_get(orig_entry->orig_node,
                         BATADV_IF_DEFAULT);
         if (!router)
             continue;
 
         if (best_router &&
             bao->neigh.cmp(router, BATADV_IF_DEFAULT, best_router,
                    BATADV_IF_DEFAULT) <= 0) {
             batadv_neigh_node_put(router);
             continue;
         }
 
         /* release the refcount for the "old" best */
         batadv_neigh_node_put(best_router);
 
         best_entry = orig_entry;
         best_router = router;
     }
 
     batadv_neigh_node_put(best_router);
 
     return best_entry;
 }
 
 /**
  * batadv_tt_global_dump_subentry() - Dump all TT local entries into a message
  * @msg: Netlink message to dump into
  * @portid: Port making netlink request
  * @seq: Sequence number of netlink message
  * @common: tt local & tt global common data
  * @orig: Originator node announcing a non-mesh client
  * @best: Is the best originator for the TT entry
  *
  * Return: Error code, or 0 on success
  */
 static int
 batadv_tt_global_dump_subentry(struct sk_buff *msg, u32 portid, u32 seq,
                    struct batadv_tt_common_entry *common,
                    struct batadv_tt_orig_list_entry *orig,
                    bool best)
 {
     u16 flags = (common->flags & (~BATADV_TT_SYNC_MASK)) | orig->flags;
     void *hdr;
     struct batadv_orig_node_vlan *vlan;
     u8 last_ttvn;
     u32 crc;
 
     vlan = batadv_orig_node_vlan_get(orig->orig_node,
                      common->vid);
     if (!vlan)
         return 0;
 
     crc = vlan->tt.crc;
 
     batadv_orig_node_vlan_put(vlan);
 
     hdr = genlmsg_put(msg, portid, seq, &batadv_netlink_family,
               NLM_F_MULTI,
               BATADV_CMD_GET_TRANSTABLE_GLOBAL);
     if (!hdr)
         return -ENOBUFS;
 
     last_ttvn = atomic_read(&orig->orig_node->last_ttvn);
 
     if (nla_put(msg, BATADV_ATTR_TT_ADDRESS, ETH_ALEN, common->addr) ||
         nla_put(msg, BATADV_ATTR_ORIG_ADDRESS, ETH_ALEN,
             orig->orig_node->orig) ||
         nla_put_u8(msg, BATADV_ATTR_TT_TTVN, orig->ttvn) ||
         nla_put_u8(msg, BATADV_ATTR_TT_LAST_TTVN, last_ttvn) ||
         nla_put_u32(msg, BATADV_ATTR_TT_CRC32, crc) ||
         nla_put_u16(msg, BATADV_ATTR_TT_VID, common->vid) ||
         nla_put_u32(msg, BATADV_ATTR_TT_FLAGS, flags))
         goto nla_put_failure;
 
     if (best && nla_put_flag(msg, BATADV_ATTR_FLAG_BEST))
         goto nla_put_failure;
 
     genlmsg_end(msg, hdr);
     return 0;
 
  nla_put_failure:
     genlmsg_cancel(msg, hdr);
     return -EMSGSIZE;
 }
 
 /**
  * batadv_tt_global_dump_entry() - Dump one TT global entry into a message
  * @msg: Netlink message to dump into
  * @portid: Port making netlink request
  * @seq: Sequence number of netlink message
  * @bat_priv: The bat priv with all the soft interface information
  * @common: tt local & tt global common data
  * @sub_s: Number of entries to skip
  *
  * This function assumes the caller holds rcu_read_lock().
  *
  * Return: Error code, or 0 on success
  */
 static int
 batadv_tt_global_dump_entry(struct sk_buff *msg, u32 portid, u32 seq,
                 struct batadv_priv *bat_priv,
                 struct batadv_tt_common_entry *common, int *sub_s)
 {
     struct batadv_tt_orig_list_entry *orig_entry, *best_entry;
     struct batadv_tt_global_entry *global;
     struct hlist_head *head;
     int sub = 0;
     bool best;
 
     global = container_of(common, struct batadv_tt_global_entry, common);
     best_entry = batadv_transtable_best_orig(bat_priv, global);
     head = &global->orig_list;
 
     hlist_for_each_entry_rcu(orig_entry, head, list) {
         if (sub++ < *sub_s)
             continue;
 
         best = (orig_entry == best_entry);
 
         if (batadv_tt_global_dump_subentry(msg, portid, seq, common,
                            orig_entry, best)) {
             *sub_s = sub - 1;
             return -EMSGSIZE;
         }
     }
 
     *sub_s = 0;
     return 0;
 }
 
 /**
  * batadv_tt_global_dump_bucket() - Dump one TT local bucket into a message
  * @msg: Netlink message to dump into
  * @portid: Port making netlink request
  * @seq: Sequence number of netlink message
  * @bat_priv: The bat priv with all the soft interface information
  * @head: Pointer to the list containing the global tt entries
  * @idx_s: Number of entries to skip
  * @sub: Number of entries to skip
  *
  * Return: Error code, or 0 on success
  */
 static int
 batadv_tt_global_dump_bucket(struct sk_buff *msg, u32 portid, u32 seq,
                  struct batadv_priv *bat_priv,
                  struct hlist_head *head, int *idx_s, int *sub)
 {
     struct batadv_tt_common_entry *common;
     int idx = 0;
 
     rcu_read_lock();
     hlist_for_each_entry_rcu(common, head, hash_entry) {
         if (idx++ < *idx_s)
             continue;
 
         if (batadv_tt_global_dump_entry(msg, portid, seq, bat_priv,
                         common, sub)) {
             rcu_read_unlock();
             *idx_s = idx - 1;
             return -EMSGSIZE;
         }
     }
     rcu_read_unlock();
 
     *idx_s = 0;
     *sub = 0;
     return 0;
 }
 
 /**
  * batadv_tt_global_dump() -  Dump TT global entries into a message
  * @msg: Netlink message to dump into
  * @cb: Parameters from query
  *
  * Return: Error code, or length of message on success
  */
 int batadv_tt_global_dump(struct sk_buff *msg, struct netlink_callback *cb)
 {
     struct net *net = sock_net(cb->skb->sk);
     struct net_device *soft_iface;
     struct batadv_priv *bat_priv;
     struct batadv_hard_iface *primary_if = NULL;
     struct batadv_hashtable *hash;
     struct hlist_head *head;
     int ret;
     int ifindex;
     int bucket = cb->args[0];
     int idx = cb->args[1];
     int sub = cb->args[2];
     int portid = NETLINK_CB(cb->skb).portid;
 
     ifindex = batadv_netlink_get_ifindex(cb->nlh, BATADV_ATTR_MESH_IFINDEX);
     if (!ifindex)
         return -EINVAL;
 
     soft_iface = dev_get_by_index(net, ifindex);
     if (!soft_iface || !batadv_softif_is_valid(soft_iface)) {
         ret = -ENODEV;
         goto out;
     }
 
     bat_priv = netdev_priv(soft_iface);
 
     primary_if = batadv_primary_if_get_selected(bat_priv);
     if (!primary_if || primary_if->if_status != BATADV_IF_ACTIVE) {
         ret = -ENOENT;
         goto out;
     }
 
     hash = bat_priv->tt.global_hash;
 
     while (bucket < hash->size) {
         head = &hash->table[bucket];
 
         if (batadv_tt_global_dump_bucket(msg, portid,
                          cb->nlh->nlmsg_seq, bat_priv,
                          head, &idx, &sub))
             break;
 
         bucket++;
     }
 
     ret = msg->len;
 
  out:
     batadv_hardif_put(primary_if);
     dev_put(soft_iface);
 
     cb->args[0] = bucket;
     cb->args[1] = idx;
     cb->args[2] = sub;
 
     return ret;
 }
 
 /**
  * _batadv_tt_global_del_orig_entry() - remove and free an orig_entry
  * @tt_global_entry: the global entry to remove the orig_entry from
  * @orig_entry: the orig entry to remove and free
  *
  * Remove an orig_entry from its list in the given tt_global_entry and
  * free this orig_entry afterwards.
  *
  * Caller must hold tt_global_entry->list_lock and ensure orig_entry->list is
  * part of a list.
  */
 static void
 _batadv_tt_global_del_orig_entry(struct batadv_tt_global_entry *tt_global_entry,
                  struct batadv_tt_orig_list_entry *orig_entry)
 {
     lockdep_assert_held(&tt_global_entry->list_lock);
 
     batadv_tt_global_size_dec(orig_entry->orig_node,
                   tt_global_entry->common.vid);
     atomic_dec(&tt_global_entry->orig_list_count);
     /* requires holding tt_global_entry->list_lock and orig_entry->list
      * being part of a list
      */
     hlist_del_rcu(&orig_entry->list);
     batadv_tt_orig_list_entry_put(orig_entry);
 }
 
 /* deletes the orig list of a tt_global_entry */
 static void
 batadv_tt_global_del_orig_list(struct batadv_tt_global_entry *tt_global_entry)
 {
     struct hlist_head *head;
     struct hlist_node *safe;
     struct batadv_tt_orig_list_entry *orig_entry;
 
     spin_lock_bh(&tt_global_entry->list_lock);
     head = &tt_global_entry->orig_list;
     hlist_for_each_entry_safe(orig_entry, safe, head, list)
         _batadv_tt_global_del_orig_entry(tt_global_entry, orig_entry);
     spin_unlock_bh(&tt_global_entry->list_lock);
 }
 
 /**
  * batadv_tt_global_del_orig_node() - remove orig_node from a global tt entry
  * @bat_priv: the bat priv with all the soft interface information
  * @tt_global_entry: the global entry to remove the orig_node from
  * @orig_node: the originator announcing the client
  * @message: message to append to the log on deletion
  *
  * Remove the given orig_node and its according orig_entry from the given
  * global tt entry.
  */
 static void
 batadv_tt_global_del_orig_node(struct batadv_priv *bat_priv,
                    struct batadv_tt_global_entry *tt_global_entry,
                    struct batadv_orig_node *orig_node,
                    const char *message)
 {
     struct hlist_head *head;
     struct hlist_node *safe;
     struct batadv_tt_orig_list_entry *orig_entry;
     unsigned short vid;
 
     spin_lock_bh(&tt_global_entry->list_lock);
     head = &tt_global_entry->orig_list;
     hlist_for_each_entry_safe(orig_entry, safe, head, list) {
         if (orig_entry->orig_node == orig_node) {
             vid = tt_global_entry->common.vid;
             batadv_dbg(BATADV_DBG_TT, bat_priv,
                    "Deleting %pM from global tt entry %pM (vid: %d): %s\n",
                    orig_node->orig,
                    tt_global_entry->common.addr,
                    batadv_print_vid(vid), message);
             _batadv_tt_global_del_orig_entry(tt_global_entry,
                              orig_entry);
         }
     }
     spin_unlock_bh(&tt_global_entry->list_lock);
 }
 
 /* If the client is to be deleted, we check if it is the last origantor entry
  * within tt_global entry. If yes, we set the BATADV_TT_CLIENT_ROAM flag and the
  * timer, otherwise we simply remove the originator scheduled for deletion.
  */
 static void
 batadv_tt_global_del_roaming(struct batadv_priv *bat_priv,
                  struct batadv_tt_global_entry *tt_global_entry,
                  struct batadv_orig_node *orig_node,
                  const char *message)
 {
     bool last_entry = true;
     struct hlist_head *head;
     struct batadv_tt_orig_list_entry *orig_entry;
 
     /* no local entry exists, case 1:
      * Check if this is the last one or if other entries exist.
      */
 
     rcu_read_lock();
     head = &tt_global_entry->orig_list;
     hlist_for_each_entry_rcu(orig_entry, head, list) {
         if (orig_entry->orig_node != orig_node) {
             last_entry = false;
             break;
         }
     }
     rcu_read_unlock();
 
     if (last_entry) {
         /* its the last one, mark for roaming. */
         tt_global_entry->common.flags |= BATADV_TT_CLIENT_ROAM;
         tt_global_entry->roam_at = jiffies;
     } else {
         /* there is another entry, we can simply delete this
          * one and can still use the other one.
          */
         batadv_tt_global_del_orig_node(bat_priv, tt_global_entry,
                            orig_node, message);
     }
 }
 
 /**
  * batadv_tt_global_del() - remove a client from the global table
  * @bat_priv: the bat priv with all the soft interface information
  * @orig_node: an originator serving this client
  * @addr: the mac address of the client
  * @vid: VLAN identifier
  * @message: a message explaining the reason for deleting the client to print
  *  for debugging purpose
  * @roaming: true if the deletion has been triggered by a roaming event
  */
 static void batadv_tt_global_del(struct batadv_priv *bat_priv,
                  struct batadv_orig_node *orig_node,
                  const unsigned char *addr, unsigned short vid,
                  const char *message, bool roaming)
 {
     struct batadv_tt_global_entry *tt_global_entry;
     struct batadv_tt_local_entry *local_entry = NULL;
 
     tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
     if (!tt_global_entry)
         goto out;
 
     if (!roaming) {
         batadv_tt_global_del_orig_node(bat_priv, tt_global_entry,
                            orig_node, message);
 
         if (hlist_empty(&tt_global_entry->orig_list))
             batadv_tt_global_free(bat_priv, tt_global_entry,
                           message);
 
         goto out;
     }
 
     /* if we are deleting a global entry due to a roam
      * event, there are two possibilities:
      * 1) the client roamed from node A to node B => if there
      *    is only one originator left for this client, we mark
      *    it with BATADV_TT_CLIENT_ROAM, we start a timer and we
      *    wait for node B to claim it. In case of timeout
      *    the entry is purged.
      *
      *    If there are other originators left, we directly delete
      *    the originator.
      * 2) the client roamed to us => we can directly delete
      *    the global entry, since it is useless now.
      */
     local_entry = batadv_tt_local_hash_find(bat_priv,
                         tt_global_entry->common.addr,
                         vid);
     if (local_entry) {
         /* local entry exists, case 2: client roamed to us. */
         batadv_tt_global_del_orig_list(tt_global_entry);
         batadv_tt_global_free(bat_priv, tt_global_entry, message);
     } else {
         /* no local entry exists, case 1: check for roaming */
         batadv_tt_global_del_roaming(bat_priv, tt_global_entry,
                          orig_node, message);
     }
 
 out:
     batadv_tt_global_entry_put(tt_global_entry);
     batadv_tt_local_entry_put(local_entry);
 }
 
 /**
  * batadv_tt_global_del_orig() - remove all the TT global entries belonging to
  *  the given originator matching the provided vid
  * @bat_priv: the bat priv with all the soft interface information
  * @orig_node: the originator owning the entries to remove
  * @match_vid: the VLAN identifier to match. If negative all the entries will be
  *  removed
  * @message: debug message to print as "reason"
  */
 void batadv_tt_global_del_orig(struct batadv_priv *bat_priv,
                    struct batadv_orig_node *orig_node,
                    s32 match_vid,
                    const char *message)
 {
     struct batadv_tt_global_entry *tt_global;
     struct batadv_tt_common_entry *tt_common_entry;
     u32 i;
     struct batadv_hashtable *hash = bat_priv->tt.global_hash;
     struct hlist_node *safe;
     struct hlist_head *head;
     spinlock_t *list_lock; /* protects write access to the hash lists */
     unsigned short vid;
 
     if (!hash)
         return;
 
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
         list_lock = &hash->list_locks[i];
 
         spin_lock_bh(list_lock);
         hlist_for_each_entry_safe(tt_common_entry, safe,
                       head, hash_entry) {
             /* remove only matching entries */
             if (match_vid >= 0 && tt_common_entry->vid != match_vid)
                 continue;
 
             tt_global = container_of(tt_common_entry,
                          struct batadv_tt_global_entry,
                          common);
 
             batadv_tt_global_del_orig_node(bat_priv, tt_global,
                                orig_node, message);
 
             if (hlist_empty(&tt_global->orig_list)) {
                 vid = tt_global->common.vid;
                 batadv_dbg(BATADV_DBG_TT, bat_priv,
                        "Deleting global tt entry %pM (vid: %d): %s\n",
                        tt_global->common.addr,
                        batadv_print_vid(vid), message);
                 hlist_del_rcu(&tt_common_entry->hash_entry);
                 batadv_tt_global_entry_put(tt_global);
             }
         }
         spin_unlock_bh(list_lock);
     }
     clear_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized);
 }
 
 static bool batadv_tt_global_to_purge(struct batadv_tt_global_entry *tt_global,
                       char **msg)
 {
     bool purge = false;
     unsigned long roam_timeout = BATADV_TT_CLIENT_ROAM_TIMEOUT;
     unsigned long temp_timeout = BATADV_TT_CLIENT_TEMP_TIMEOUT;
 
     if ((tt_global->common.flags & BATADV_TT_CLIENT_ROAM) &&
         batadv_has_timed_out(tt_global->roam_at, roam_timeout)) {
         purge = true;
         *msg = "Roaming timeout\n";
     }
 
     if ((tt_global->common.flags & BATADV_TT_CLIENT_TEMP) &&
         batadv_has_timed_out(tt_global->common.added_at, temp_timeout)) {
         purge = true;
         *msg = "Temporary client timeout\n";
     }
 
     return purge;
 }
 
 static void batadv_tt_global_purge(struct batadv_priv *bat_priv)
 {
     struct batadv_hashtable *hash = bat_priv->tt.global_hash;
     struct hlist_head *head;
     struct hlist_node *node_tmp;
     spinlock_t *list_lock; /* protects write access to the hash lists */
     u32 i;
     char *msg = NULL;
     struct batadv_tt_common_entry *tt_common;
     struct batadv_tt_global_entry *tt_global;
 
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
         list_lock = &hash->list_locks[i];
 
         spin_lock_bh(list_lock);
         hlist_for_each_entry_safe(tt_common, node_tmp, head,
                       hash_entry) {
             tt_global = container_of(tt_common,
                          struct batadv_tt_global_entry,
                          common);
 
             if (!batadv_tt_global_to_purge(tt_global, &msg))
                 continue;
 
             batadv_dbg(BATADV_DBG_TT, bat_priv,
                    "Deleting global tt entry %pM (vid: %d): %s\n",
                    tt_global->common.addr,
                    batadv_print_vid(tt_global->common.vid),
                    msg);
 
             hlist_del_rcu(&tt_common->hash_entry);
 
             batadv_tt_global_entry_put(tt_global);
         }
         spin_unlock_bh(list_lock);
     }
 }
 
 static void batadv_tt_global_table_free(struct batadv_priv *bat_priv)
 {
     struct batadv_hashtable *hash;
     spinlock_t *list_lock; /* protects write access to the hash lists */
     struct batadv_tt_common_entry *tt_common_entry;
     struct batadv_tt_global_entry *tt_global;
     struct hlist_node *node_tmp;
     struct hlist_head *head;
     u32 i;
 
     if (!bat_priv->tt.global_hash)
         return;
 
     hash = bat_priv->tt.global_hash;
 
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
         list_lock = &hash->list_locks[i];
 
         spin_lock_bh(list_lock);
         hlist_for_each_entry_safe(tt_common_entry, node_tmp,
                       head, hash_entry) {
             hlist_del_rcu(&tt_common_entry->hash_entry);
             tt_global = container_of(tt_common_entry,
                          struct batadv_tt_global_entry,
                          common);
             batadv_tt_global_entry_put(tt_global);
         }
         spin_unlock_bh(list_lock);
     }
 
     batadv_hash_destroy(hash);
 
     bat_priv->tt.global_hash = NULL;
 }
 
 static bool
 _batadv_is_ap_isolated(struct batadv_tt_local_entry *tt_local_entry,
                struct batadv_tt_global_entry *tt_global_entry)
 {
     if (tt_local_entry->common.flags & BATADV_TT_CLIENT_WIFI &&
         tt_global_entry->common.flags & BATADV_TT_CLIENT_WIFI)
         return true;
 
     /* check if the two clients are marked as isolated */
     if (tt_local_entry->common.flags & BATADV_TT_CLIENT_ISOLA &&
         tt_global_entry->common.flags & BATADV_TT_CLIENT_ISOLA)
         return true;
 
     return false;
 }
 
 /**
  * batadv_transtable_search() - get the mesh destination for a given client
  * @bat_priv: the bat priv with all the soft interface information
  * @src: mac address of the source client
  * @addr: mac address of the destination client
  * @vid: VLAN identifier
  *
  * Return: a pointer to the originator that was selected as destination in the
  * mesh for contacting the client 'addr', NULL otherwise.
  * In case of multiple originators serving the same client, the function returns
  * the best one (best in terms of metric towards the destination node).
  *
  * If the two clients are AP isolated the function returns NULL.
  */
 struct batadv_orig_node *batadv_transtable_search(struct batadv_priv *bat_priv,
                           const u8 *src,
                           const u8 *addr,
                           unsigned short vid)
 {
     struct batadv_tt_local_entry *tt_local_entry = NULL;
     struct batadv_tt_global_entry *tt_global_entry = NULL;
     struct batadv_orig_node *orig_node = NULL;
     struct batadv_tt_orig_list_entry *best_entry;
 
     if (src && batadv_vlan_ap_isola_get(bat_priv, vid)) {
         tt_local_entry = batadv_tt_local_hash_find(bat_priv, src, vid);
         if (!tt_local_entry ||
             (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING))
             goto out;
     }
 
     tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
     if (!tt_global_entry)
         goto out;
 
     /* check whether the clients should not communicate due to AP
      * isolation
      */
     if (tt_local_entry &&
         _batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
         goto out;
 
     rcu_read_lock();
     best_entry = batadv_transtable_best_orig(bat_priv, tt_global_entry);
     /* found anything? */
     if (best_entry)
         orig_node = best_entry->orig_node;
     if (orig_node && !kref_get_unless_zero(&orig_node->refcount))
         orig_node = NULL;
     rcu_read_unlock();
 
 out:
     batadv_tt_global_entry_put(tt_global_entry);
     batadv_tt_local_entry_put(tt_local_entry);
 
     return orig_node;
 }
 
 /**
  * batadv_tt_global_crc() - calculates the checksum of the local table belonging
  *  to the given orig_node
  * @bat_priv: the bat priv with all the soft interface information
  * @orig_node: originator for which the CRC should be computed
  * @vid: VLAN identifier for which the CRC32 has to be computed
  *
  * This function computes the checksum for the global table corresponding to a
  * specific originator. In particular, the checksum is computed as follows: For
  * each client connected to the originator the CRC32C of the MAC address and the
  * VID is computed and then all the CRC32Cs of the various clients are xor'ed
  * together.
  *
  * The idea behind is that CRC32C should be used as much as possible in order to
  * produce a unique hash of the table, but since the order which is used to feed
  * the CRC32C function affects the result and since every node in the network
  * probably sorts the clients differently, the hash function cannot be directly
  * computed over the entire table. Hence the CRC32C is used only on
  * the single client entry, while all the results are then xor'ed together
  * because the XOR operation can combine them all while trying to reduce the
  * noise as much as possible.
  *
  * Return: the checksum of the global table of a given originator.
  */
 static u32 batadv_tt_global_crc(struct batadv_priv *bat_priv,
                 struct batadv_orig_node *orig_node,
                 unsigned short vid)
 {
     struct batadv_hashtable *hash = bat_priv->tt.global_hash;
     struct batadv_tt_orig_list_entry *tt_orig;
     struct batadv_tt_common_entry *tt_common;
     struct batadv_tt_global_entry *tt_global;
     struct hlist_head *head;
     u32 i, crc_tmp, crc = 0;
     u8 flags;
     __be16 tmp_vid;
 
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
 
         rcu_read_lock();
         hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
             tt_global = container_of(tt_common,
                          struct batadv_tt_global_entry,
                          common);
             /* compute the CRC only for entries belonging to the
              * VLAN identified by the vid passed as parameter
              */
             if (tt_common->vid != vid)
                 continue;
 
             /* Roaming clients are in the global table for
              * consistency only. They don't have to be
              * taken into account while computing the
              * global crc
              */
             if (tt_common->flags & BATADV_TT_CLIENT_ROAM)
                 continue;
             /* Temporary clients have not been announced yet, so
              * they have to be skipped while computing the global
              * crc
              */
             if (tt_common->flags & BATADV_TT_CLIENT_TEMP)
                 continue;
 
             /* find out if this global entry is announced by this
              * originator
              */
             tt_orig = batadv_tt_global_orig_entry_find(tt_global,
                                    orig_node);
             if (!tt_orig)
                 continue;
 
             /* use network order to read the VID: this ensures that
              * every node reads the bytes in the same order.
              */
             tmp_vid = htons(tt_common->vid);
             crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid));
 
             /* compute the CRC on flags that have to be kept in sync
              * among nodes
              */
             flags = tt_orig->flags;
             crc_tmp = crc32c(crc_tmp, &flags, sizeof(flags));
 
             crc ^= crc32c(crc_tmp, tt_common->addr, ETH_ALEN);
 
             batadv_tt_orig_list_entry_put(tt_orig);
         }
         rcu_read_unlock();
     }
 
     return crc;
 }
 
 /**
  * batadv_tt_local_crc() - calculates the checksum of the local table
  * @bat_priv: the bat priv with all the soft interface information
  * @vid: VLAN identifier for which the CRC32 has to be computed
  *
  * For details about the computation, please refer to the documentation for
  * batadv_tt_global_crc().
  *
  * Return: the checksum of the local table
  */
 static u32 batadv_tt_local_crc(struct batadv_priv *bat_priv,
                    unsigned short vid)
 {
     struct batadv_hashtable *hash = bat_priv->tt.local_hash;
     struct batadv_tt_common_entry *tt_common;
     struct hlist_head *head;
     u32 i, crc_tmp, crc = 0;
     u8 flags;
     __be16 tmp_vid;
 
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
 
         rcu_read_lock();
         hlist_for_each_entry_rcu(tt_common, head, hash_entry) {
             /* compute the CRC only for entries belonging to the
              * VLAN identified by vid
              */
             if (tt_common->vid != vid)
                 continue;
 
             /* not yet committed clients have not to be taken into
              * account while computing the CRC
              */
             if (tt_common->flags & BATADV_TT_CLIENT_NEW)
                 continue;
 
             /* use network order to read the VID: this ensures that
              * every node reads the bytes in the same order.
              */
             tmp_vid = htons(tt_common->vid);
             crc_tmp = crc32c(0, &tmp_vid, sizeof(tmp_vid));
 
             /* compute the CRC on flags that have to be kept in sync
              * among nodes
              */
             flags = tt_common->flags & BATADV_TT_SYNC_MASK;
             crc_tmp = crc32c(crc_tmp, &flags, sizeof(flags));
 
             crc ^= crc32c(crc_tmp, tt_common->addr, ETH_ALEN);
         }
         rcu_read_unlock();
     }
 
     return crc;
 }
 
 /**
  * batadv_tt_req_node_release() - free tt_req node entry
  * @ref: kref pointer of the tt req_node entry
  */
 static void batadv_tt_req_node_release(struct kref *ref)
 {
     struct batadv_tt_req_node *tt_req_node;
 
     tt_req_node = container_of(ref, struct batadv_tt_req_node, refcount);
 
     kmem_cache_free(batadv_tt_req_cache, tt_req_node);
 }
 
 /**
  * batadv_tt_req_node_put() - decrement the tt_req_node refcounter and
  *  possibly release it
  * @tt_req_node: tt_req_node to be free'd
  */
 static void batadv_tt_req_node_put(struct batadv_tt_req_node *tt_req_node)
 {
     if (!tt_req_node)
         return;
 
     kref_put(&tt_req_node->refcount, batadv_tt_req_node_release);
 }
 
 static void batadv_tt_req_list_free(struct batadv_priv *bat_priv)
 {
     struct batadv_tt_req_node *node;
     struct hlist_node *safe;
 
     spin_lock_bh(&bat_priv->tt.req_list_lock);
 
     hlist_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
         hlist_del_init(&node->list);
         batadv_tt_req_node_put(node);
     }
 
     spin_unlock_bh(&bat_priv->tt.req_list_lock);
 }
 
 static void batadv_tt_save_orig_buffer(struct batadv_priv *bat_priv,
                        struct batadv_orig_node *orig_node,
                        const void *tt_buff,
                        u16 tt_buff_len)
 {
     /* Replace the old buffer only if I received something in the
      * last OGM (the OGM could carry no changes)
      */
     spin_lock_bh(&orig_node->tt_buff_lock);
     if (tt_buff_len > 0) {
         kfree(orig_node->tt_buff);
         orig_node->tt_buff_len = 0;
         orig_node->tt_buff = kmalloc(tt_buff_len, GFP_ATOMIC);
         if (orig_node->tt_buff) {
             memcpy(orig_node->tt_buff, tt_buff, tt_buff_len);
             orig_node->tt_buff_len = tt_buff_len;
         }
     }
     spin_unlock_bh(&orig_node->tt_buff_lock);
 }
 
 static void batadv_tt_req_purge(struct batadv_priv *bat_priv)
 {
     struct batadv_tt_req_node *node;
     struct hlist_node *safe;
 
     spin_lock_bh(&bat_priv->tt.req_list_lock);
     hlist_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
         if (batadv_has_timed_out(node->issued_at,
                      BATADV_TT_REQUEST_TIMEOUT)) {
             hlist_del_init(&node->list);
             batadv_tt_req_node_put(node);
         }
     }
     spin_unlock_bh(&bat_priv->tt.req_list_lock);
 }
 
 /**
  * batadv_tt_req_node_new() - search and possibly create a tt_req_node object
  * @bat_priv: the bat priv with all the soft interface information
  * @orig_node: orig node this request is being issued for
  *
  * Return: the pointer to the new tt_req_node struct if no request
  * has already been issued for this orig_node, NULL otherwise.
  */
 static struct batadv_tt_req_node *
 batadv_tt_req_node_new(struct batadv_priv *bat_priv,
                struct batadv_orig_node *orig_node)
 {
     struct batadv_tt_req_node *tt_req_node_tmp, *tt_req_node = NULL;
 
     spin_lock_bh(&bat_priv->tt.req_list_lock);
     hlist_for_each_entry(tt_req_node_tmp, &bat_priv->tt.req_list, list) {
         if (batadv_compare_eth(tt_req_node_tmp, orig_node) &&
             !batadv_has_timed_out(tt_req_node_tmp->issued_at,
                       BATADV_TT_REQUEST_TIMEOUT))
             goto unlock;
     }
 
     tt_req_node = kmem_cache_alloc(batadv_tt_req_cache, GFP_ATOMIC);
     if (!tt_req_node)
         goto unlock;
 
     kref_init(&tt_req_node->refcount);
     ether_addr_copy(tt_req_node->addr, orig_node->orig);
     tt_req_node->issued_at = jiffies;
 
     kref_get(&tt_req_node->refcount);
     hlist_add_head(&tt_req_node->list, &bat_priv->tt.req_list);
 unlock:
     spin_unlock_bh(&bat_priv->tt.req_list_lock);
     return tt_req_node;
 }
 
 /**
  * batadv_tt_local_valid() - verify local tt entry and get flags
  * @entry_ptr: to be checked local tt entry
  * @data_ptr: not used but definition required to satisfy the callback prototype
  * @flags: a pointer to store TT flags for this client to
  *
  * Checks the validity of the given local TT entry. If it is, then the provided
  * flags pointer is updated.
  *
  * Return: true if the entry is a valid, false otherwise.
  */
 static bool batadv_tt_local_valid(const void *entry_ptr,
                   const void *data_ptr,
                   u8 *flags)
 {
     const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
 
     if (tt_common_entry->flags & BATADV_TT_CLIENT_NEW)
         return false;
 
     if (flags)
         *flags = tt_common_entry->flags;
 
     return true;
 }
 
 /**
  * batadv_tt_global_valid() - verify global tt entry and get flags
  * @entry_ptr: to be checked global tt entry
  * @data_ptr: an orig_node object (may be NULL)
  * @flags: a pointer to store TT flags for this client to
  *
  * Checks the validity of the given global TT entry. If it is, then the provided
  * flags pointer is updated either with the common (summed) TT flags if data_ptr
  * is NULL or the specific, per originator TT flags otherwise.
  *
  * Return: true if the entry is a valid, false otherwise.
  */
 static bool batadv_tt_global_valid(const void *entry_ptr,
                    const void *data_ptr,
                    u8 *flags)
 {
     const struct batadv_tt_common_entry *tt_common_entry = entry_ptr;
     const struct batadv_tt_global_entry *tt_global_entry;
     const struct batadv_orig_node *orig_node = data_ptr;
 
     if (tt_common_entry->flags & BATADV_TT_CLIENT_ROAM ||
         tt_common_entry->flags & BATADV_TT_CLIENT_TEMP)
         return false;
 
     tt_global_entry = container_of(tt_common_entry,
                        struct batadv_tt_global_entry,
                        common);
 
     return batadv_tt_global_entry_has_orig(tt_global_entry, orig_node,
                            flags);
 }
 
 /**
  * batadv_tt_tvlv_generate() - fill the tvlv buff with the tt entries from the
  *  specified tt hash
  * @bat_priv: the bat priv with all the soft interface information
  * @hash: hash table containing the tt entries
  * @tt_len: expected tvlv tt data buffer length in number of bytes
  * @tvlv_buff: pointer to the buffer to fill with the TT data
  * @valid_cb: function to filter tt change entries and to return TT flags
  * @cb_data: data passed to the filter function as argument
  *
  * Fills the tvlv buff with the tt entries from the specified hash. If valid_cb
  * is not provided then this becomes a no-op.
  */
 static void batadv_tt_tvlv_generate(struct batadv_priv *bat_priv,
                     struct batadv_hashtable *hash,
                     void *tvlv_buff, u16 tt_len,
                     bool (*valid_cb)(const void *,
                              const void *,
                              u8 *flags),
                     void *cb_data)
 {
     struct batadv_tt_common_entry *tt_common_entry;
     struct batadv_tvlv_tt_change *tt_change;
     struct hlist_head *head;
     u16 tt_tot, tt_num_entries = 0;
     u8 flags;
     bool ret;
     u32 i;
 
     tt_tot = batadv_tt_entries(tt_len);
     tt_change = tvlv_buff;
 
     if (!valid_cb)
         return;
 
     rcu_read_lock();
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
 
         hlist_for_each_entry_rcu(tt_common_entry,
                      head, hash_entry) {
             if (tt_tot == tt_num_entries)
                 break;
 
             ret = valid_cb(tt_common_entry, cb_data, &flags);
             if (!ret)
                 continue;
 
             ether_addr_copy(tt_change->addr, tt_common_entry->addr);
             tt_change->flags = flags;
             tt_change->vid = htons(tt_common_entry->vid);
             memset(tt_change->reserved, 0,
                    sizeof(tt_change->reserved));
 
             tt_num_entries++;
             tt_change++;
         }
     }
     rcu_read_unlock();
 }
 
 /**
  * batadv_tt_global_check_crc() - check if all the CRCs are correct
  * @orig_node: originator for which the CRCs have to be checked
  * @tt_vlan: pointer to the first tvlv VLAN entry
  * @num_vlan: number of tvlv VLAN entries
  *
  * Return: true if all the received CRCs match the locally stored ones, false
  * otherwise
  */
 static bool batadv_tt_global_check_crc(struct batadv_orig_node *orig_node,
                        struct batadv_tvlv_tt_vlan_data *tt_vlan,
                        u16 num_vlan)
 {
     struct batadv_tvlv_tt_vlan_data *tt_vlan_tmp;
     struct batadv_orig_node_vlan *vlan;
     int i, orig_num_vlan;
     u32 crc;
 
     /* check if each received CRC matches the locally stored one */
     for (i = 0; i < num_vlan; i++) {
         tt_vlan_tmp = tt_vlan + i;
 
         /* if orig_node is a backbone node for this VLAN, don't check
          * the CRC as we ignore all the global entries over it
          */
         if (batadv_bla_is_backbone_gw_orig(orig_node->bat_priv,
                            orig_node->orig,
                            ntohs(tt_vlan_tmp->vid)))
             continue;
 
         vlan = batadv_orig_node_vlan_get(orig_node,
                          ntohs(tt_vlan_tmp->vid));
         if (!vlan)
             return false;
 
         crc = vlan->tt.crc;
         batadv_orig_node_vlan_put(vlan);
 
         if (crc != ntohl(tt_vlan_tmp->crc))
             return false;
     }
 
     /* check if any excess VLANs exist locally for the originator
      * which are not mentioned in the TVLV from the originator.
      */
     rcu_read_lock();
     orig_num_vlan = 0;
     hlist_for_each_entry_rcu(vlan, &orig_node->vlan_list, list)
         orig_num_vlan++;
     rcu_read_unlock();
 
     if (orig_num_vlan > num_vlan)
         return false;
 
     return true;
 }
 
 /**
  * batadv_tt_local_update_crc() - update all the local CRCs
  * @bat_priv: the bat priv with all the soft interface information
  */
 static void batadv_tt_local_update_crc(struct batadv_priv *bat_priv)
 {
     struct batadv_softif_vlan *vlan;
 
     /* recompute the global CRC for each VLAN */
     rcu_read_lock();
     hlist_for_each_entry_rcu(vlan, &bat_priv->softif_vlan_list, list) {
         vlan->tt.crc = batadv_tt_local_crc(bat_priv, vlan->vid);
     }
     rcu_read_unlock();
 }
 
 /**
  * batadv_tt_global_update_crc() - update all the global CRCs for this orig_node
  * @bat_priv: the bat priv with all the soft interface information
  * @orig_node: the orig_node for which the CRCs have to be updated
  */
 static void batadv_tt_global_update_crc(struct batadv_priv *bat_priv,
                     struct batadv_orig_node *orig_node)
 {
     struct batadv_orig_node_vlan *vlan;
     u32 crc;
 
     /* recompute the global CRC for each VLAN */
     rcu_read_lock();
     hlist_for_each_entry_rcu(vlan, &orig_node->vlan_list, list) {
         /* if orig_node is a backbone node for this VLAN, don't compute
          * the CRC as we ignore all the global entries over it
          */
         if (batadv_bla_is_backbone_gw_orig(bat_priv, orig_node->orig,
                            vlan->vid))
             continue;
 
         crc = batadv_tt_global_crc(bat_priv, orig_node, vlan->vid);
         vlan->tt.crc = crc;
     }
     rcu_read_unlock();
 }
 
 /**
  * batadv_send_tt_request() - send a TT Request message to a given node
  * @bat_priv: the bat priv with all the soft interface information
  * @dst_orig_node: the destination of the message
  * @ttvn: the version number that the source of the message is looking for
  * @tt_vlan: pointer to the first tvlv VLAN object to request
  * @num_vlan: number of tvlv VLAN entries
  * @full_table: ask for the entire translation table if true, while only for the
  *  last TT diff otherwise
  *
  * Return: true if the TT Request was sent, false otherwise
  */
 static bool batadv_send_tt_request(struct batadv_priv *bat_priv,
                    struct batadv_orig_node *dst_orig_node,
                    u8 ttvn,
                    struct batadv_tvlv_tt_vlan_data *tt_vlan,
                    u16 num_vlan, bool full_table)
 {
     struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
     struct batadv_tt_req_node *tt_req_node = NULL;
     struct batadv_tvlv_tt_vlan_data *tt_vlan_req;
     struct batadv_hard_iface *primary_if;
     bool ret = false;
     int i, size;
 
     primary_if = batadv_primary_if_get_selected(bat_priv);
     if (!primary_if)
         goto out;
 
     /* The new tt_req will be issued only if I'm not waiting for a
      * reply from the same orig_node yet
      */
     tt_req_node = batadv_tt_req_node_new(bat_priv, dst_orig_node);
     if (!tt_req_node)
         goto out;
 
     size = sizeof(*tvlv_tt_data) + sizeof(*tt_vlan_req) * num_vlan;
     tvlv_tt_data = kzalloc(size, GFP_ATOMIC);
     if (!tvlv_tt_data)
         goto out;
 
     tvlv_tt_data->flags = BATADV_TT_REQUEST;
     tvlv_tt_data->ttvn = ttvn;
     tvlv_tt_data->num_vlan = htons(num_vlan);
 
     /* send all the CRCs within the request. This is needed by intermediate
      * nodes to ensure they have the correct table before replying
      */
     tt_vlan_req = (struct batadv_tvlv_tt_vlan_data *)(tvlv_tt_data + 1);
     for (i = 0; i < num_vlan; i++) {
         tt_vlan_req->vid = tt_vlan->vid;
         tt_vlan_req->crc = tt_vlan->crc;
 
         tt_vlan_req++;
         tt_vlan++;
     }
 
     if (full_table)
         tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv, "Sending TT_REQUEST to %pM [%c]\n",
            dst_orig_node->orig, full_table ? 'F' : '.');
 
     batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_TX);
     batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
                  dst_orig_node->orig, BATADV_TVLV_TT, 1,
                  tvlv_tt_data, size);
     ret = true;
 
 out:
     batadv_hardif_put(primary_if);
 
     if (ret && tt_req_node) {
         spin_lock_bh(&bat_priv->tt.req_list_lock);
         if (!hlist_unhashed(&tt_req_node->list)) {
             hlist_del_init(&tt_req_node->list);
             batadv_tt_req_node_put(tt_req_node);
         }
         spin_unlock_bh(&bat_priv->tt.req_list_lock);
     }
 
     batadv_tt_req_node_put(tt_req_node);
 
     kfree(tvlv_tt_data);
     return ret;
 }
 
 /**
  * batadv_send_other_tt_response() - send reply to tt request concerning another
  *  node's translation table
  * @bat_priv: the bat priv with all the soft interface information
  * @tt_data: tt data containing the tt request information
  * @req_src: mac address of tt request sender
  * @req_dst: mac address of tt request recipient
  *
  * Return: true if tt request reply was sent, false otherwise.
  */
 static bool batadv_send_other_tt_response(struct batadv_priv *bat_priv,
                       struct batadv_tvlv_tt_data *tt_data,
                       u8 *req_src, u8 *req_dst)
 {
     struct batadv_orig_node *req_dst_orig_node;
     struct batadv_orig_node *res_dst_orig_node = NULL;
     struct batadv_tvlv_tt_change *tt_change;
     struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
     struct batadv_tvlv_tt_vlan_data *tt_vlan;
     bool ret = false, full_table;
     u8 orig_ttvn, req_ttvn;
     u16 tvlv_len;
     s32 tt_len;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Received TT_REQUEST from %pM for ttvn: %u (%pM) [%c]\n",
            req_src, tt_data->ttvn, req_dst,
            ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));
 
     /* Let's get the orig node of the REAL destination */
     req_dst_orig_node = batadv_orig_hash_find(bat_priv, req_dst);
     if (!req_dst_orig_node)
         goto out;
 
     res_dst_orig_node = batadv_orig_hash_find(bat_priv, req_src);
     if (!res_dst_orig_node)
         goto out;
 
     orig_ttvn = (u8)atomic_read(&req_dst_orig_node->last_ttvn);
     req_ttvn = tt_data->ttvn;
 
     tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(tt_data + 1);
     /* this node doesn't have the requested data */
     if (orig_ttvn != req_ttvn ||
         !batadv_tt_global_check_crc(req_dst_orig_node, tt_vlan,
                     ntohs(tt_data->num_vlan)))
         goto out;
 
     /* If the full table has been explicitly requested */
     if (tt_data->flags & BATADV_TT_FULL_TABLE ||
         !req_dst_orig_node->tt_buff)
         full_table = true;
     else
         full_table = false;
 
     /* TT fragmentation hasn't been implemented yet, so send as many
      * TT entries fit a single packet as possible only
      */
     if (!full_table) {
         spin_lock_bh(&req_dst_orig_node->tt_buff_lock);
         tt_len = req_dst_orig_node->tt_buff_len;
 
         tvlv_len = batadv_tt_prepare_tvlv_global_data(req_dst_orig_node,
                                   &tvlv_tt_data,
                                   &tt_change,
                                   &tt_len);
         if (!tt_len)
             goto unlock;
 
         /* Copy the last orig_node's OGM buffer */
         memcpy(tt_change, req_dst_orig_node->tt_buff,
                req_dst_orig_node->tt_buff_len);
         spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
     } else {
         /* allocate the tvlv, put the tt_data and all the tt_vlan_data
          * in the initial part
          */
         tt_len = -1;
         tvlv_len = batadv_tt_prepare_tvlv_global_data(req_dst_orig_node,
                                   &tvlv_tt_data,
                                   &tt_change,
                                   &tt_len);
         if (!tt_len)
             goto out;
 
         /* fill the rest of the tvlv with the real TT entries */
         batadv_tt_tvlv_generate(bat_priv, bat_priv->tt.global_hash,
                     tt_change, tt_len,
                     batadv_tt_global_valid,
                     req_dst_orig_node);
     }
 
     /* Don't send the response, if larger than fragmented packet. */
     tt_len = sizeof(struct batadv_unicast_tvlv_packet) + tvlv_len;
     if (tt_len > atomic_read(&bat_priv->packet_size_max)) {
         net_ratelimited_function(batadv_info, bat_priv->soft_iface,
                      "Ignoring TT_REQUEST from %pM; Response size exceeds max packet size.\n",
                      res_dst_orig_node->orig);
         goto out;
     }
 
     tvlv_tt_data->flags = BATADV_TT_RESPONSE;
     tvlv_tt_data->ttvn = req_ttvn;
 
     if (full_table)
         tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Sending TT_RESPONSE %pM for %pM [%c] (ttvn: %u)\n",
            res_dst_orig_node->orig, req_dst_orig_node->orig,
            full_table ? 'F' : '.', req_ttvn);
 
     batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
 
     batadv_tvlv_unicast_send(bat_priv, req_dst_orig_node->orig,
                  req_src, BATADV_TVLV_TT, 1, tvlv_tt_data,
                  tvlv_len);
 
     ret = true;
     goto out;
 
 unlock:
     spin_unlock_bh(&req_dst_orig_node->tt_buff_lock);
 
 out:
     batadv_orig_node_put(res_dst_orig_node);
     batadv_orig_node_put(req_dst_orig_node);
     kfree(tvlv_tt_data);
     return ret;
 }
 
 /**
  * batadv_send_my_tt_response() - send reply to tt request concerning this
  *  node's translation table
  * @bat_priv: the bat priv with all the soft interface information
  * @tt_data: tt data containing the tt request information
  * @req_src: mac address of tt request sender
  *
  * Return: true if tt request reply was sent, false otherwise.
  */
 static bool batadv_send_my_tt_response(struct batadv_priv *bat_priv,
                        struct batadv_tvlv_tt_data *tt_data,
                        u8 *req_src)
 {
     struct batadv_tvlv_tt_data *tvlv_tt_data = NULL;
     struct batadv_hard_iface *primary_if = NULL;
     struct batadv_tvlv_tt_change *tt_change;
     struct batadv_orig_node *orig_node;
     u8 my_ttvn, req_ttvn;
     u16 tvlv_len;
     bool full_table;
     s32 tt_len;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Received TT_REQUEST from %pM for ttvn: %u (me) [%c]\n",
            req_src, tt_data->ttvn,
            ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));
 
     spin_lock_bh(&bat_priv->tt.commit_lock);
 
     my_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
     req_ttvn = tt_data->ttvn;
 
     orig_node = batadv_orig_hash_find(bat_priv, req_src);
     if (!orig_node)
         goto out;
 
     primary_if = batadv_primary_if_get_selected(bat_priv);
     if (!primary_if)
         goto out;
 
     /* If the full table has been explicitly requested or the gap
      * is too big send the whole local translation table
      */
     if (tt_data->flags & BATADV_TT_FULL_TABLE || my_ttvn != req_ttvn ||
         !bat_priv->tt.last_changeset)
         full_table = true;
     else
         full_table = false;
 
     /* TT fragmentation hasn't been implemented yet, so send as many
      * TT entries fit a single packet as possible only
      */
     if (!full_table) {
         spin_lock_bh(&bat_priv->tt.last_changeset_lock);
 
         tt_len = bat_priv->tt.last_changeset_len;
         tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv,
                                  &tvlv_tt_data,
                                  &tt_change,
                                  &tt_len);
         if (!tt_len || !tvlv_len)
             goto unlock;
 
         /* Copy the last orig_node's OGM buffer */
         memcpy(tt_change, bat_priv->tt.last_changeset,
                bat_priv->tt.last_changeset_len);
         spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
     } else {
         req_ttvn = (u8)atomic_read(&bat_priv->tt.vn);
 
         /* allocate the tvlv, put the tt_data and all the tt_vlan_data
          * in the initial part
          */
         tt_len = -1;
         tvlv_len = batadv_tt_prepare_tvlv_local_data(bat_priv,
                                  &tvlv_tt_data,
                                  &tt_change,
                                  &tt_len);
         if (!tt_len || !tvlv_len)
             goto out;
 
         /* fill the rest of the tvlv with the real TT entries */
         batadv_tt_tvlv_generate(bat_priv, bat_priv->tt.local_hash,
                     tt_change, tt_len,
                     batadv_tt_local_valid, NULL);
     }
 
     tvlv_tt_data->flags = BATADV_TT_RESPONSE;
     tvlv_tt_data->ttvn = req_ttvn;
 
     if (full_table)
         tvlv_tt_data->flags |= BATADV_TT_FULL_TABLE;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Sending TT_RESPONSE to %pM [%c] (ttvn: %u)\n",
            orig_node->orig, full_table ? 'F' : '.', req_ttvn);
 
     batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_TX);
 
     batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
                  req_src, BATADV_TVLV_TT, 1, tvlv_tt_data,
                  tvlv_len);
 
     goto out;
 
 unlock:
     spin_unlock_bh(&bat_priv->tt.last_changeset_lock);
 out:
     spin_unlock_bh(&bat_priv->tt.commit_lock);
     batadv_orig_node_put(orig_node);
     batadv_hardif_put(primary_if);
     kfree(tvlv_tt_data);
     /* The packet was for this host, so it doesn't need to be re-routed */
     return true;
 }
 
 /**
  * batadv_send_tt_response() - send reply to tt request
  * @bat_priv: the bat priv with all the soft interface information
  * @tt_data: tt data containing the tt request information
  * @req_src: mac address of tt request sender
  * @req_dst: mac address of tt request recipient
  *
  * Return: true if tt request reply was sent, false otherwise.
  */
 static bool batadv_send_tt_response(struct batadv_priv *bat_priv,
                     struct batadv_tvlv_tt_data *tt_data,
                     u8 *req_src, u8 *req_dst)
 {
     if (batadv_is_my_mac(bat_priv, req_dst))
         return batadv_send_my_tt_response(bat_priv, tt_data, req_src);
     return batadv_send_other_tt_response(bat_priv, tt_data, req_src,
                          req_dst);
 }
 
 static void _batadv_tt_update_changes(struct batadv_priv *bat_priv,
                       struct batadv_orig_node *orig_node,
                       struct batadv_tvlv_tt_change *tt_change,
                       u16 tt_num_changes, u8 ttvn)
 {
     int i;
     int roams;
 
     for (i = 0; i < tt_num_changes; i++) {
         if ((tt_change + i)->flags & BATADV_TT_CLIENT_DEL) {
             roams = (tt_change + i)->flags & BATADV_TT_CLIENT_ROAM;
             batadv_tt_global_del(bat_priv, orig_node,
                          (tt_change + i)->addr,
                          ntohs((tt_change + i)->vid),
                          "tt removed by changes",
                          roams);
         } else {
             if (!batadv_tt_global_add(bat_priv, orig_node,
                           (tt_change + i)->addr,
                           ntohs((tt_change + i)->vid),
                           (tt_change + i)->flags, ttvn))
                 /* In case of problem while storing a
                  * global_entry, we stop the updating
                  * procedure without committing the
                  * ttvn change. This will avoid to send
                  * corrupted data on tt_request
                  */
                 return;
         }
     }
     set_bit(BATADV_ORIG_CAPA_HAS_TT, &orig_node->capa_initialized);
 }
 
 static void batadv_tt_fill_gtable(struct batadv_priv *bat_priv,
                   struct batadv_tvlv_tt_change *tt_change,
                   u8 ttvn, u8 *resp_src,
                   u16 num_entries)
 {
     struct batadv_orig_node *orig_node;
 
     orig_node = batadv_orig_hash_find(bat_priv, resp_src);
     if (!orig_node)
         goto out;
 
     /* Purge the old table first.. */
     batadv_tt_global_del_orig(bat_priv, orig_node, -1,
                   "Received full table");
 
     _batadv_tt_update_changes(bat_priv, orig_node, tt_change, num_entries,
                   ttvn);
 
     spin_lock_bh(&orig_node->tt_buff_lock);
     kfree(orig_node->tt_buff);
     orig_node->tt_buff_len = 0;
     orig_node->tt_buff = NULL;
     spin_unlock_bh(&orig_node->tt_buff_lock);
 
     atomic_set(&orig_node->last_ttvn, ttvn);
 
 out:
     batadv_orig_node_put(orig_node);
 }
 
 static void batadv_tt_update_changes(struct batadv_priv *bat_priv,
                      struct batadv_orig_node *orig_node,
                      u16 tt_num_changes, u8 ttvn,
                      struct batadv_tvlv_tt_change *tt_change)
 {
     _batadv_tt_update_changes(bat_priv, orig_node, tt_change,
                   tt_num_changes, ttvn);
 
     batadv_tt_save_orig_buffer(bat_priv, orig_node, tt_change,
                    batadv_tt_len(tt_num_changes));
     atomic_set(&orig_node->last_ttvn, ttvn);
 }
 
 /**
  * batadv_is_my_client() - check if a client is served by the local node
  * @bat_priv: the bat priv with all the soft interface information
  * @addr: the mac address of the client to check
  * @vid: VLAN identifier
  *
  * Return: true if the client is served by this node, false otherwise.
  */
 bool batadv_is_my_client(struct batadv_priv *bat_priv, const u8 *addr,
              unsigned short vid)
 {
     struct batadv_tt_local_entry *tt_local_entry;
     bool ret = false;
 
     tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
     if (!tt_local_entry)
         goto out;
     /* Check if the client has been logically deleted (but is kept for
      * consistency purpose)
      */
     if ((tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING) ||
         (tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM))
         goto out;
     ret = true;
 out:
     batadv_tt_local_entry_put(tt_local_entry);
     return ret;
 }
 
 /**
  * batadv_handle_tt_response() - process incoming tt reply
  * @bat_priv: the bat priv with all the soft interface information
  * @tt_data: tt data containing the tt request information
  * @resp_src: mac address of tt reply sender
  * @num_entries: number of tt change entries appended to the tt data
  */
 static void batadv_handle_tt_response(struct batadv_priv *bat_priv,
                       struct batadv_tvlv_tt_data *tt_data,
                       u8 *resp_src, u16 num_entries)
 {
     struct batadv_tt_req_node *node;
     struct hlist_node *safe;
     struct batadv_orig_node *orig_node = NULL;
     struct batadv_tvlv_tt_change *tt_change;
     u8 *tvlv_ptr = (u8 *)tt_data;
     u16 change_offset;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Received TT_RESPONSE from %pM for ttvn %d t_size: %d [%c]\n",
            resp_src, tt_data->ttvn, num_entries,
            ((tt_data->flags & BATADV_TT_FULL_TABLE) ? 'F' : '.'));
 
     orig_node = batadv_orig_hash_find(bat_priv, resp_src);
     if (!orig_node)
         goto out;
 
     spin_lock_bh(&orig_node->tt_lock);
 
     change_offset = sizeof(struct batadv_tvlv_tt_vlan_data);
     change_offset *= ntohs(tt_data->num_vlan);
     change_offset += sizeof(*tt_data);
     tvlv_ptr += change_offset;
 
     tt_change = (struct batadv_tvlv_tt_change *)tvlv_ptr;
     if (tt_data->flags & BATADV_TT_FULL_TABLE) {
         batadv_tt_fill_gtable(bat_priv, tt_change, tt_data->ttvn,
                       resp_src, num_entries);
     } else {
         batadv_tt_update_changes(bat_priv, orig_node, num_entries,
                      tt_data->ttvn, tt_change);
     }
 
     /* Recalculate the CRC for this orig_node and store it */
     batadv_tt_global_update_crc(bat_priv, orig_node);
 
     spin_unlock_bh(&orig_node->tt_lock);
 
     /* Delete the tt_req_node from pending tt_requests list */
     spin_lock_bh(&bat_priv->tt.req_list_lock);
     hlist_for_each_entry_safe(node, safe, &bat_priv->tt.req_list, list) {
         if (!batadv_compare_eth(node->addr, resp_src))
             continue;
         hlist_del_init(&node->list);
         batadv_tt_req_node_put(node);
     }
 
     spin_unlock_bh(&bat_priv->tt.req_list_lock);
 out:
     batadv_orig_node_put(orig_node);
 }
 
 static void batadv_tt_roam_list_free(struct batadv_priv *bat_priv)
 {
     struct batadv_tt_roam_node *node, *safe;
 
     spin_lock_bh(&bat_priv->tt.roam_list_lock);
 
     list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
         list_del(&node->list);
         kmem_cache_free(batadv_tt_roam_cache, node);
     }
 
     spin_unlock_bh(&bat_priv->tt.roam_list_lock);
 }
 
 static void batadv_tt_roam_purge(struct batadv_priv *bat_priv)
 {
     struct batadv_tt_roam_node *node, *safe;
 
     spin_lock_bh(&bat_priv->tt.roam_list_lock);
     list_for_each_entry_safe(node, safe, &bat_priv->tt.roam_list, list) {
         if (!batadv_has_timed_out(node->first_time,
                       BATADV_ROAMING_MAX_TIME))
             continue;
 
         list_del(&node->list);
         kmem_cache_free(batadv_tt_roam_cache, node);
     }
     spin_unlock_bh(&bat_priv->tt.roam_list_lock);
 }
 
 /**
  * batadv_tt_check_roam_count() - check if a client has roamed too frequently
  * @bat_priv: the bat priv with all the soft interface information
  * @client: mac address of the roaming client
  *
  * This function checks whether the client already reached the
  * maximum number of possible roaming phases. In this case the ROAMING_ADV
  * will not be sent.
  *
  * Return: true if the ROAMING_ADV can be sent, false otherwise
  */
 static bool batadv_tt_check_roam_count(struct batadv_priv *bat_priv, u8 *client)
 {
     struct batadv_tt_roam_node *tt_roam_node;
     bool ret = false;
 
     spin_lock_bh(&bat_priv->tt.roam_list_lock);
     /* The new tt_req will be issued only if I'm not waiting for a
      * reply from the same orig_node yet
      */
     list_for_each_entry(tt_roam_node, &bat_priv->tt.roam_list, list) {
         if (!batadv_compare_eth(tt_roam_node->addr, client))
             continue;
 
         if (batadv_has_timed_out(tt_roam_node->first_time,
                      BATADV_ROAMING_MAX_TIME))
             continue;
 
         if (!batadv_atomic_dec_not_zero(&tt_roam_node->counter))
             /* Sorry, you roamed too many times! */
             goto unlock;
         ret = true;
         break;
     }
 
     if (!ret) {
         tt_roam_node = kmem_cache_alloc(batadv_tt_roam_cache,
                         GFP_ATOMIC);
         if (!tt_roam_node)
             goto unlock;
 
         tt_roam_node->first_time = jiffies;
         atomic_set(&tt_roam_node->counter,
                BATADV_ROAMING_MAX_COUNT - 1);
         ether_addr_copy(tt_roam_node->addr, client);
 
         list_add(&tt_roam_node->list, &bat_priv->tt.roam_list);
         ret = true;
     }
 
 unlock:
     spin_unlock_bh(&bat_priv->tt.roam_list_lock);
     return ret;
 }
 
 /**
  * batadv_send_roam_adv() - send a roaming advertisement message
  * @bat_priv: the bat priv with all the soft interface information
  * @client: mac address of the roaming client
  * @vid: VLAN identifier
  * @orig_node: message destination
  *
  * Send a ROAMING_ADV message to the node which was previously serving this
  * client. This is done to inform the node that from now on all traffic destined
  * for this particular roamed client has to be forwarded to the sender of the
  * roaming message.
  */
 static void batadv_send_roam_adv(struct batadv_priv *bat_priv, u8 *client,
                  unsigned short vid,
                  struct batadv_orig_node *orig_node)
 {
     struct batadv_hard_iface *primary_if;
     struct batadv_tvlv_roam_adv tvlv_roam;
 
     primary_if = batadv_primary_if_get_selected(bat_priv);
     if (!primary_if)
         goto out;
 
     /* before going on we have to check whether the client has
      * already roamed to us too many times
      */
     if (!batadv_tt_check_roam_count(bat_priv, client))
         goto out;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Sending ROAMING_ADV to %pM (client %pM, vid: %d)\n",
            orig_node->orig, client, batadv_print_vid(vid));
 
     batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_TX);
 
     memcpy(tvlv_roam.client, client, sizeof(tvlv_roam.client));
     tvlv_roam.vid = htons(vid);
 
     batadv_tvlv_unicast_send(bat_priv, primary_if->net_dev->dev_addr,
                  orig_node->orig, BATADV_TVLV_ROAM, 1,
                  &tvlv_roam, sizeof(tvlv_roam));
 
 out:
     batadv_hardif_put(primary_if);
 }
 
 static void batadv_tt_purge(struct work_struct *work)
 {
     struct delayed_work *delayed_work;
     struct batadv_priv_tt *priv_tt;
     struct batadv_priv *bat_priv;
 
     delayed_work = to_delayed_work(work);
     priv_tt = container_of(delayed_work, struct batadv_priv_tt, work);
     bat_priv = container_of(priv_tt, struct batadv_priv, tt);
 
     batadv_tt_local_purge(bat_priv, BATADV_TT_LOCAL_TIMEOUT);
     batadv_tt_global_purge(bat_priv);
     batadv_tt_req_purge(bat_priv);
     batadv_tt_roam_purge(bat_priv);
 
     queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
                msecs_to_jiffies(BATADV_TT_WORK_PERIOD));
 }
 
 /**
  * batadv_tt_free() - Free translation table of soft interface
  * @bat_priv: the bat priv with all the soft interface information
  */
 void batadv_tt_free(struct batadv_priv *bat_priv)
 {
     batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_ROAM, 1);
 
     batadv_tvlv_container_unregister(bat_priv, BATADV_TVLV_TT, 1);
     batadv_tvlv_handler_unregister(bat_priv, BATADV_TVLV_TT, 1);
 
     cancel_delayed_work_sync(&bat_priv->tt.work);
 
     batadv_tt_local_table_free(bat_priv);
     batadv_tt_global_table_free(bat_priv);
     batadv_tt_req_list_free(bat_priv);
     batadv_tt_changes_list_free(bat_priv);
     batadv_tt_roam_list_free(bat_priv);
 
     kfree(bat_priv->tt.last_changeset);
 }
 
 /**
  * batadv_tt_local_set_flags() - set or unset the specified flags on the local
  *  table and possibly count them in the TT size
  * @bat_priv: the bat priv with all the soft interface information
  * @flags: the flag to switch
  * @enable: whether to set or unset the flag
  * @count: whether to increase the TT size by the number of changed entries
  */
 static void batadv_tt_local_set_flags(struct batadv_priv *bat_priv, u16 flags,
                       bool enable, bool count)
 {
     struct batadv_hashtable *hash = bat_priv->tt.local_hash;
     struct batadv_tt_common_entry *tt_common_entry;
     struct hlist_head *head;
     u32 i;
 
     if (!hash)
         return;
 
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
 
         rcu_read_lock();
         hlist_for_each_entry_rcu(tt_common_entry,
                      head, hash_entry) {
             if (enable) {
                 if ((tt_common_entry->flags & flags) == flags)
                     continue;
                 tt_common_entry->flags |= flags;
             } else {
                 if (!(tt_common_entry->flags & flags))
                     continue;
                 tt_common_entry->flags &= ~flags;
             }
 
             if (!count)
                 continue;
 
             batadv_tt_local_size_inc(bat_priv,
                          tt_common_entry->vid);
         }
         rcu_read_unlock();
     }
 }
 
 /* Purge out all the tt local entries marked with BATADV_TT_CLIENT_PENDING */
 static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv)
 {
     struct batadv_hashtable *hash = bat_priv->tt.local_hash;
     struct batadv_tt_common_entry *tt_common;
     struct batadv_tt_local_entry *tt_local;
     struct hlist_node *node_tmp;
     struct hlist_head *head;
     spinlock_t *list_lock; /* protects write access to the hash lists */
     u32 i;
 
     if (!hash)
         return;
 
     for (i = 0; i < hash->size; i++) {
         head = &hash->table[i];
         list_lock = &hash->list_locks[i];
 
         spin_lock_bh(list_lock);
         hlist_for_each_entry_safe(tt_common, node_tmp, head,
                       hash_entry) {
             if (!(tt_common->flags & BATADV_TT_CLIENT_PENDING))
                 continue;
 
             batadv_dbg(BATADV_DBG_TT, bat_priv,
                    "Deleting local tt entry (%pM, vid: %d): pending\n",
                    tt_common->addr,
                    batadv_print_vid(tt_common->vid));
 
             batadv_tt_local_size_dec(bat_priv, tt_common->vid);
             hlist_del_rcu(&tt_common->hash_entry);
             tt_local = container_of(tt_common,
                         struct batadv_tt_local_entry,
                         common);
 
             batadv_tt_local_entry_put(tt_local);
         }
         spin_unlock_bh(list_lock);
     }
 }
 
 /**
  * batadv_tt_local_commit_changes_nolock() - commit all pending local tt changes
  *  which have been queued in the time since the last commit
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Caller must hold tt->commit_lock.
  */
 static void batadv_tt_local_commit_changes_nolock(struct batadv_priv *bat_priv)
 {
     lockdep_assert_held(&bat_priv->tt.commit_lock);
 
     if (atomic_read(&bat_priv->tt.local_changes) < 1) {
         if (!batadv_atomic_dec_not_zero(&bat_priv->tt.ogm_append_cnt))
             batadv_tt_tvlv_container_update(bat_priv);
         return;
     }
 
     batadv_tt_local_set_flags(bat_priv, BATADV_TT_CLIENT_NEW, false, true);
 
     batadv_tt_local_purge_pending_clients(bat_priv);
     batadv_tt_local_update_crc(bat_priv);
 
     /* Increment the TTVN only once per OGM interval */
     atomic_inc(&bat_priv->tt.vn);
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Local changes committed, updating to ttvn %u\n",
            (u8)atomic_read(&bat_priv->tt.vn));
 
     /* reset the sending counter */
     atomic_set(&bat_priv->tt.ogm_append_cnt, BATADV_TT_OGM_APPEND_MAX);
     batadv_tt_tvlv_container_update(bat_priv);
 }
 
 /**
  * batadv_tt_local_commit_changes() - commit all pending local tt changes which
  *  have been queued in the time since the last commit
  * @bat_priv: the bat priv with all the soft interface information
  */
 void batadv_tt_local_commit_changes(struct batadv_priv *bat_priv)
 {
     spin_lock_bh(&bat_priv->tt.commit_lock);
     batadv_tt_local_commit_changes_nolock(bat_priv);
     spin_unlock_bh(&bat_priv->tt.commit_lock);
 }
 
 /**
  * batadv_is_ap_isolated() - Check if packet from upper layer should be dropped
  * @bat_priv: the bat priv with all the soft interface information
  * @src: source mac address of packet
  * @dst: destination mac address of packet
  * @vid: vlan id of packet
  *
  * Return: true when src+dst(+vid) pair should be isolated, false otherwise
  */
 bool batadv_is_ap_isolated(struct batadv_priv *bat_priv, u8 *src, u8 *dst,
                unsigned short vid)
 {
     struct batadv_tt_local_entry *tt_local_entry;
     struct batadv_tt_global_entry *tt_global_entry;
     struct batadv_softif_vlan *vlan;
     bool ret = false;
 
     vlan = batadv_softif_vlan_get(bat_priv, vid);
     if (!vlan)
         return false;
 
     if (!atomic_read(&vlan->ap_isolation))
         goto vlan_put;
 
     tt_local_entry = batadv_tt_local_hash_find(bat_priv, dst, vid);
     if (!tt_local_entry)
         goto vlan_put;
 
     tt_global_entry = batadv_tt_global_hash_find(bat_priv, src, vid);
     if (!tt_global_entry)
         goto local_entry_put;
 
     if (_batadv_is_ap_isolated(tt_local_entry, tt_global_entry))
         ret = true;
 
     batadv_tt_global_entry_put(tt_global_entry);
 local_entry_put:
     batadv_tt_local_entry_put(tt_local_entry);
 vlan_put:
     batadv_softif_vlan_put(vlan);
     return ret;
 }
 
 /**
  * batadv_tt_update_orig() - update global translation table with new tt
  *  information received via ogms
  * @bat_priv: the bat priv with all the soft interface information
  * @orig_node: the orig_node of the ogm
  * @tt_buff: pointer to the first tvlv VLAN entry
  * @tt_num_vlan: number of tvlv VLAN entries
  * @tt_change: pointer to the first entry in the TT buffer
  * @tt_num_changes: number of tt changes inside the tt buffer
  * @ttvn: translation table version number of this changeset
  */
 static void batadv_tt_update_orig(struct batadv_priv *bat_priv,
                   struct batadv_orig_node *orig_node,
                   const void *tt_buff, u16 tt_num_vlan,
                   struct batadv_tvlv_tt_change *tt_change,
                   u16 tt_num_changes, u8 ttvn)
 {
     u8 orig_ttvn = (u8)atomic_read(&orig_node->last_ttvn);
     struct batadv_tvlv_tt_vlan_data *tt_vlan;
     bool full_table = true;
     bool has_tt_init;
 
     tt_vlan = (struct batadv_tvlv_tt_vlan_data *)tt_buff;
     has_tt_init = test_bit(BATADV_ORIG_CAPA_HAS_TT,
                    &orig_node->capa_initialized);
 
     /* orig table not initialised AND first diff is in the OGM OR the ttvn
      * increased by one -> we can apply the attached changes
      */
     if ((!has_tt_init && ttvn == 1) || ttvn - orig_ttvn == 1) {
         /* the OGM could not contain the changes due to their size or
          * because they have already been sent BATADV_TT_OGM_APPEND_MAX
          * times.
          * In this case send a tt request
          */
         if (!tt_num_changes) {
             full_table = false;
             goto request_table;
         }
 
         spin_lock_bh(&orig_node->tt_lock);
 
         batadv_tt_update_changes(bat_priv, orig_node, tt_num_changes,
                      ttvn, tt_change);
 
         /* Even if we received the precomputed crc with the OGM, we
          * prefer to recompute it to spot any possible inconsistency
          * in the global table
          */
         batadv_tt_global_update_crc(bat_priv, orig_node);
 
         spin_unlock_bh(&orig_node->tt_lock);
 
         /* The ttvn alone is not enough to guarantee consistency
          * because a single value could represent different states
          * (due to the wrap around). Thus a node has to check whether
          * the resulting table (after applying the changes) is still
          * consistent or not. E.g. a node could disconnect while its
          * ttvn is X and reconnect on ttvn = X + TTVN_MAX: in this case
          * checking the CRC value is mandatory to detect the
          * inconsistency
          */
         if (!batadv_tt_global_check_crc(orig_node, tt_vlan,
                         tt_num_vlan))
             goto request_table;
     } else {
         /* if we missed more than one change or our tables are not
          * in sync anymore -> request fresh tt data
          */
         if (!has_tt_init || ttvn != orig_ttvn ||
             !batadv_tt_global_check_crc(orig_node, tt_vlan,
                         tt_num_vlan)) {
 request_table:
             batadv_dbg(BATADV_DBG_TT, bat_priv,
                    "TT inconsistency for %pM. Need to retrieve the correct information (ttvn: %u last_ttvn: %u num_changes: %u)\n",
                    orig_node->orig, ttvn, orig_ttvn,
                    tt_num_changes);
             batadv_send_tt_request(bat_priv, orig_node, ttvn,
                            tt_vlan, tt_num_vlan,
                            full_table);
             return;
         }
     }
 }
 
 /**
  * batadv_tt_global_client_is_roaming() - check if a client is marked as roaming
  * @bat_priv: the bat priv with all the soft interface information
  * @addr: the mac address of the client to check
  * @vid: VLAN identifier
  *
  * Return: true if we know that the client has moved from its old originator
  * to another one. This entry is still kept for consistency purposes and will be
  * deleted later by a DEL or because of timeout
  */
 bool batadv_tt_global_client_is_roaming(struct batadv_priv *bat_priv,
                     u8 *addr, unsigned short vid)
 {
     struct batadv_tt_global_entry *tt_global_entry;
     bool ret = false;
 
     tt_global_entry = batadv_tt_global_hash_find(bat_priv, addr, vid);
     if (!tt_global_entry)
         goto out;
 
     ret = tt_global_entry->common.flags & BATADV_TT_CLIENT_ROAM;
     batadv_tt_global_entry_put(tt_global_entry);
 out:
     return ret;
 }
 
 /**
  * batadv_tt_local_client_is_roaming() - tells whether the client is roaming
  * @bat_priv: the bat priv with all the soft interface information
  * @addr: the mac address of the local client to query
  * @vid: VLAN identifier
  *
  * Return: true if the local client is known to be roaming (it is not served by
  * this node anymore) or not. If yes, the client is still present in the table
  * to keep the latter consistent with the node TTVN
  */
 bool batadv_tt_local_client_is_roaming(struct batadv_priv *bat_priv,
                        u8 *addr, unsigned short vid)
 {
     struct batadv_tt_local_entry *tt_local_entry;
     bool ret = false;
 
     tt_local_entry = batadv_tt_local_hash_find(bat_priv, addr, vid);
     if (!tt_local_entry)
         goto out;
 
     ret = tt_local_entry->common.flags & BATADV_TT_CLIENT_ROAM;
     batadv_tt_local_entry_put(tt_local_entry);
 out:
     return ret;
 }
 
 /**
  * batadv_tt_add_temporary_global_entry() - Add temporary entry to global TT
  * @bat_priv: the bat priv with all the soft interface information
  * @orig_node: orig node which the temporary entry should be associated with
  * @addr: mac address of the client
  * @vid: VLAN id of the new temporary global translation table
  *
  * Return: true when temporary tt entry could be added, false otherwise
  */
 bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv,
                       struct batadv_orig_node *orig_node,
                       const unsigned char *addr,
                       unsigned short vid)
 {
     /* ignore loop detect macs, they are not supposed to be in the tt local
      * data as well.
      */
     if (batadv_bla_is_loopdetect_mac(addr))
         return false;
 
     if (!batadv_tt_global_add(bat_priv, orig_node, addr, vid,
                   BATADV_TT_CLIENT_TEMP,
                   atomic_read(&orig_node->last_ttvn)))
         return false;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Added temporary global client (addr: %pM, vid: %d, orig: %pM)\n",
            addr, batadv_print_vid(vid), orig_node->orig);
 
     return true;
 }
 
 /**
  * batadv_tt_local_resize_to_mtu() - resize the local translation table fit the
  *  maximum packet size that can be transported through the mesh
  * @soft_iface: netdev struct of the mesh interface
  *
  * Remove entries older than 'timeout' and half timeout if more entries need
  * to be removed.
  */
 void batadv_tt_local_resize_to_mtu(struct net_device *soft_iface)
 {
     struct batadv_priv *bat_priv = netdev_priv(soft_iface);
     int packet_size_max = atomic_read(&bat_priv->packet_size_max);
     int table_size, timeout = BATADV_TT_LOCAL_TIMEOUT / 2;
     bool reduced = false;
 
     spin_lock_bh(&bat_priv->tt.commit_lock);
 
     while (true) {
         table_size = batadv_tt_local_table_transmit_size(bat_priv);
         if (packet_size_max >= table_size)
             break;
 
         batadv_tt_local_purge(bat_priv, timeout);
         batadv_tt_local_purge_pending_clients(bat_priv);
 
         timeout /= 2;
         reduced = true;
         net_ratelimited_function(batadv_info, soft_iface,
                      "Forced to purge local tt entries to fit new maximum fragment MTU (%i)\n",
                      packet_size_max);
     }
 
     /* commit these changes immediately, to avoid synchronization problem
      * with the TTVN
      */
     if (reduced)
         batadv_tt_local_commit_changes_nolock(bat_priv);
 
     spin_unlock_bh(&bat_priv->tt.commit_lock);
 }
 
 /**
  * batadv_tt_tvlv_ogm_handler_v1() - process incoming tt tvlv container
  * @bat_priv: the bat priv with all the soft interface information
  * @orig: the orig_node of the ogm
  * @flags: flags indicating the tvlv state (see batadv_tvlv_handler_flags)
  * @tvlv_value: tvlv buffer containing the gateway data
  * @tvlv_value_len: tvlv buffer length
  */
 static void batadv_tt_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
                       struct batadv_orig_node *orig,
                       u8 flags, void *tvlv_value,
                       u16 tvlv_value_len)
 {
     struct batadv_tvlv_tt_vlan_data *tt_vlan;
     struct batadv_tvlv_tt_change *tt_change;
     struct batadv_tvlv_tt_data *tt_data;
     u16 num_entries, num_vlan;
 
     if (tvlv_value_len < sizeof(*tt_data))
         return;
 
     tt_data = tvlv_value;
     tvlv_value_len -= sizeof(*tt_data);
 
     num_vlan = ntohs(tt_data->num_vlan);
 
     if (tvlv_value_len < sizeof(*tt_vlan) * num_vlan)
         return;
 
     tt_vlan = (struct batadv_tvlv_tt_vlan_data *)(tt_data + 1);
     tt_change = (struct batadv_tvlv_tt_change *)(tt_vlan + num_vlan);
     tvlv_value_len -= sizeof(*tt_vlan) * num_vlan;
 
     num_entries = batadv_tt_entries(tvlv_value_len);
 
     batadv_tt_update_orig(bat_priv, orig, tt_vlan, num_vlan, tt_change,
                   num_entries, tt_data->ttvn);
 }
 
 /**
  * batadv_tt_tvlv_unicast_handler_v1() - process incoming (unicast) tt tvlv
  *  container
  * @bat_priv: the bat priv with all the soft interface information
  * @src: mac address of tt tvlv sender
  * @dst: mac address of tt tvlv recipient
  * @tvlv_value: tvlv buffer containing the tt data
  * @tvlv_value_len: tvlv buffer length
  *
  * Return: NET_RX_DROP if the tt tvlv is to be re-routed, NET_RX_SUCCESS
  * otherwise.
  */
 static int batadv_tt_tvlv_unicast_handler_v1(struct batadv_priv *bat_priv,
                          u8 *src, u8 *dst,
                          void *tvlv_value,
                          u16 tvlv_value_len)
 {
     struct batadv_tvlv_tt_data *tt_data;
     u16 tt_vlan_len, tt_num_entries;
     char tt_flag;
     bool ret;
 
     if (tvlv_value_len < sizeof(*tt_data))
         return NET_RX_SUCCESS;
 
     tt_data = tvlv_value;
     tvlv_value_len -= sizeof(*tt_data);
 
     tt_vlan_len = sizeof(struct batadv_tvlv_tt_vlan_data);
     tt_vlan_len *= ntohs(tt_data->num_vlan);
 
     if (tvlv_value_len < tt_vlan_len)
         return NET_RX_SUCCESS;
 
     tvlv_value_len -= tt_vlan_len;
     tt_num_entries = batadv_tt_entries(tvlv_value_len);
 
     switch (tt_data->flags & BATADV_TT_DATA_TYPE_MASK) {
     case BATADV_TT_REQUEST:
         batadv_inc_counter(bat_priv, BATADV_CNT_TT_REQUEST_RX);
 
         /* If this node cannot provide a TT response the tt_request is
          * forwarded
          */
         ret = batadv_send_tt_response(bat_priv, tt_data, src, dst);
         if (!ret) {
             if (tt_data->flags & BATADV_TT_FULL_TABLE)
                 tt_flag = 'F';
             else
                 tt_flag = '.';
 
             batadv_dbg(BATADV_DBG_TT, bat_priv,
                    "Routing TT_REQUEST to %pM [%c]\n",
                    dst, tt_flag);
             /* tvlv API will re-route the packet */
             return NET_RX_DROP;
         }
         break;
     case BATADV_TT_RESPONSE:
         batadv_inc_counter(bat_priv, BATADV_CNT_TT_RESPONSE_RX);
 
         if (batadv_is_my_mac(bat_priv, dst)) {
             batadv_handle_tt_response(bat_priv, tt_data,
                           src, tt_num_entries);
             return NET_RX_SUCCESS;
         }
 
         if (tt_data->flags & BATADV_TT_FULL_TABLE)
             tt_flag =  'F';
         else
             tt_flag = '.';
 
         batadv_dbg(BATADV_DBG_TT, bat_priv,
                "Routing TT_RESPONSE to %pM [%c]\n", dst, tt_flag);
 
         /* tvlv API will re-route the packet */
         return NET_RX_DROP;
     }
 
     return NET_RX_SUCCESS;
 }
 
 /**
  * batadv_roam_tvlv_unicast_handler_v1() - process incoming tt roam tvlv
  *  container
  * @bat_priv: the bat priv with all the soft interface information
  * @src: mac address of tt tvlv sender
  * @dst: mac address of tt tvlv recipient
  * @tvlv_value: tvlv buffer containing the tt data
  * @tvlv_value_len: tvlv buffer length
  *
  * Return: NET_RX_DROP if the tt roam tvlv is to be re-routed, NET_RX_SUCCESS
  * otherwise.
  */
 static int batadv_roam_tvlv_unicast_handler_v1(struct batadv_priv *bat_priv,
                            u8 *src, u8 *dst,
                            void *tvlv_value,
                            u16 tvlv_value_len)
 {
     struct batadv_tvlv_roam_adv *roaming_adv;
     struct batadv_orig_node *orig_node = NULL;
 
     /* If this node is not the intended recipient of the
      * roaming advertisement the packet is forwarded
      * (the tvlv API will re-route the packet).
      */
     if (!batadv_is_my_mac(bat_priv, dst))
         return NET_RX_DROP;
 
     if (tvlv_value_len < sizeof(*roaming_adv))
         goto out;
 
     orig_node = batadv_orig_hash_find(bat_priv, src);
     if (!orig_node)
         goto out;
 
     batadv_inc_counter(bat_priv, BATADV_CNT_TT_ROAM_ADV_RX);
     roaming_adv = tvlv_value;
 
     batadv_dbg(BATADV_DBG_TT, bat_priv,
            "Received ROAMING_ADV from %pM (client %pM)\n",
            src, roaming_adv->client);
 
     batadv_tt_global_add(bat_priv, orig_node, roaming_adv->client,
                  ntohs(roaming_adv->vid), BATADV_TT_CLIENT_ROAM,
                  atomic_read(&orig_node->last_ttvn) + 1);
 
 out:
     batadv_orig_node_put(orig_node);
     return NET_RX_SUCCESS;
 }
 
 /**
  * batadv_tt_init() - initialise the translation table internals
  * @bat_priv: the bat priv with all the soft interface information
  *
  * Return: 0 on success or negative error number in case of failure.
  */
 int batadv_tt_init(struct batadv_priv *bat_priv)
 {
     int ret;
 
     /* synchronized flags must be remote */
     BUILD_BUG_ON(!(BATADV_TT_SYNC_MASK & BATADV_TT_REMOTE_MASK));
 
     ret = batadv_tt_local_init(bat_priv);
     if (ret < 0)
         return ret;
 
     ret = batadv_tt_global_init(bat_priv);
     if (ret < 0) {
         batadv_tt_local_table_free(bat_priv);
         return ret;
     }
 
     batadv_tvlv_handler_register(bat_priv, batadv_tt_tvlv_ogm_handler_v1,
                      batadv_tt_tvlv_unicast_handler_v1,
                      BATADV_TVLV_TT, 1, BATADV_NO_FLAGS);
 
     batadv_tvlv_handler_register(bat_priv, NULL,
                      batadv_roam_tvlv_unicast_handler_v1,
                      BATADV_TVLV_ROAM, 1, BATADV_NO_FLAGS);
 
     INIT_DELAYED_WORK(&bat_priv->tt.work, batadv_tt_purge);
     queue_delayed_work(batadv_event_workqueue, &bat_priv->tt.work,
                msecs_to_jiffies(BATADV_TT_WORK_PERIOD));
 
     return 1;
 }
 
 /**
  * batadv_tt_global_is_isolated() - check if a client is marked as isolated
  * @bat_priv: the bat priv with all the soft interface information
  * @addr: the mac address of the client
  * @vid: the identifier of the VLAN where this client is connected
  *
  * Return: true if the client is marked with the TT_CLIENT_ISOLA flag, false
  * otherwise
  */
 bool batadv_tt_global_is_isolated(struct batadv_priv *bat_priv,
                   const u8 *addr, unsigned short vid)
 {
     struct batadv_tt_global_entry *tt;
     bool ret;
 
     tt = batadv_tt_global_hash_find(bat_priv, addr, vid);
     if (!tt)
         return false;
 
     ret = tt->common.flags & BATADV_TT_CLIENT_ISOLA;
 
     batadv_tt_global_entry_put(tt);
 
     return ret;
 }
 
 /**
  * batadv_tt_cache_init() - Initialize tt memory object cache
  *
  * Return: 0 on success or negative error number in case of failure.
  */
 int __init batadv_tt_cache_init(void)
 {
     size_t tl_size = sizeof(struct batadv_tt_local_entry);
     size_t tg_size = sizeof(struct batadv_tt_global_entry);
     size_t tt_orig_size = sizeof(struct batadv_tt_orig_list_entry);
     size_t tt_change_size = sizeof(struct batadv_tt_change_node);
     size_t tt_req_size = sizeof(struct batadv_tt_req_node);
     size_t tt_roam_size = sizeof(struct batadv_tt_roam_node);
 
     batadv_tl_cache = kmem_cache_create("batadv_tl_cache", tl_size, 0,
                         SLAB_HWCACHE_ALIGN, NULL);
     if (!batadv_tl_cache)
         return -ENOMEM;
 
     batadv_tg_cache = kmem_cache_create("batadv_tg_cache", tg_size, 0,
                         SLAB_HWCACHE_ALIGN, NULL);
     if (!batadv_tg_cache)
         goto err_tt_tl_destroy;
 
     batadv_tt_orig_cache = kmem_cache_create("batadv_tt_orig_cache",
                          tt_orig_size, 0,
                          SLAB_HWCACHE_ALIGN, NULL);
     if (!batadv_tt_orig_cache)
         goto err_tt_tg_destroy;
 
     batadv_tt_change_cache = kmem_cache_create("batadv_tt_change_cache",
                            tt_change_size, 0,
                            SLAB_HWCACHE_ALIGN, NULL);
     if (!batadv_tt_change_cache)
         goto err_tt_orig_destroy;
 
     batadv_tt_req_cache = kmem_cache_create("batadv_tt_req_cache",
                         tt_req_size, 0,
                         SLAB_HWCACHE_ALIGN, NULL);
     if (!batadv_tt_req_cache)
         goto err_tt_change_destroy;
 
     batadv_tt_roam_cache = kmem_cache_create("batadv_tt_roam_cache",
                          tt_roam_size, 0,
                          SLAB_HWCACHE_ALIGN, NULL);
     if (!batadv_tt_roam_cache)
         goto err_tt_req_destroy;
 
     return 0;
 
 err_tt_req_destroy:
     kmem_cache_destroy(batadv_tt_req_cache);
     batadv_tt_req_cache = NULL;
 err_tt_change_destroy:
     kmem_cache_destroy(batadv_tt_change_cache);
     batadv_tt_change_cache = NULL;
 err_tt_orig_destroy:
     kmem_cache_destroy(batadv_tt_orig_cache);
     batadv_tt_orig_cache = NULL;
 err_tt_tg_destroy:
     kmem_cache_destroy(batadv_tg_cache);
     batadv_tg_cache = NULL;
 err_tt_tl_destroy:
     kmem_cache_destroy(batadv_tl_cache);
     batadv_tl_cache = NULL;
 
     return -ENOMEM;
 }
 
 /**
  * batadv_tt_cache_destroy() - Destroy tt memory object cache
  */
 void batadv_tt_cache_destroy(void)
 {
     kmem_cache_destroy(batadv_tl_cache);
     kmem_cache_destroy(batadv_tg_cache);
     kmem_cache_destroy(batadv_tt_orig_cache);
     kmem_cache_destroy(batadv_tt_change_cache);
     kmem_cache_destroy(batadv_tt_req_cache);
     kmem_cache_destroy(batadv_tt_roam_cache);
 }