batman-adv: protect the local and the global trans-tables with rcu

The local and the global translation-tables are now lock free and rcu
protected.

Signed-off-by: Antonio Quartulli <ordex@autistici.org>
Acked-by: Simon Wunderlich <siwu@hrz.tu-chemnitz.de>
Signed-off-by: Sven Eckelmann <sven@narfation.org>

diff --git a/net/batman-adv/main.c b/net/batman-adv/main.c
index 3318ee27fe23a59cb48a7dceb661bc4c44d67221..c2b06b71d574b03d39d72061491e6adfba114c00 100644 (file)
--- a/net/batman-adv/main.c
+++ b/net/batman-adv/main.c
@@ -84,8 +84,6 @@ int mesh_init(struct net_device *soft_iface)
 
        spin_lock_init(&bat_priv->forw_bat_list_lock);
        spin_lock_init(&bat_priv->forw_bcast_list_lock);
-       spin_lock_init(&bat_priv->tt_lhash_lock);
-       spin_lock_init(&bat_priv->tt_ghash_lock);
        spin_lock_init(&bat_priv->tt_changes_list_lock);
        spin_lock_init(&bat_priv->tt_req_list_lock);
        spin_lock_init(&bat_priv->tt_roam_list_lock);

diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index 05d50ca3c4dbf552d247f74246b263b2bfccf4cf..0ce090c9fe86b2395dfe1df311b233c53286a06f 100644 (file)
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -90,9 +90,7 @@ static void update_transtable(struct bat_priv *bat_priv,
                /* Even if we received the crc into the OGM, we prefer
                 * to recompute it to spot any possible inconsistency
                 * in the global table */
-               spin_lock_bh(&bat_priv->tt_ghash_lock);
                orig_node->tt_crc = tt_global_crc(bat_priv, orig_node);
-               spin_unlock_bh(&bat_priv->tt_ghash_lock);
                /* Roaming phase is over: tables are in sync again. I can
                 * unset the flag */
                orig_node->tt_poss_change = false;

diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index d516d8591cfcb5af67bdf3d9e67580fb43167a7e..5f1fcd5736332aa7db10137591d17344f4fedbe7 100644 (file)
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -80,6 +80,9 @@ static struct tt_local_entry *tt_local_hash_find(struct bat_priv *bat_priv,
                if (!compare_eth(tt_local_entry, data))
                        continue;
 
+               if (!atomic_inc_not_zero(&tt_local_entry->refcount))
+                       continue;
+
                tt_local_entry_tmp = tt_local_entry;
                break;
        }
@@ -109,6 +112,9 @@ static struct tt_global_entry *tt_global_hash_find(struct bat_priv *bat_priv,
                if (!compare_eth(tt_global_entry, data))
                        continue;
 
+               if (!atomic_inc_not_zero(&tt_global_entry->refcount))
+                       continue;
+
                tt_global_entry_tmp = tt_global_entry;
                break;
        }
@@ -125,8 +131,20 @@ static bool is_out_of_time(unsigned long starting_time, unsigned long timeout)
        return time_after(jiffies, deadline);
 }
 
+static void tt_local_entry_free_ref(struct tt_local_entry *tt_local_entry)
+{
+       if (atomic_dec_and_test(&tt_local_entry->refcount))
+               kfree_rcu(tt_local_entry, rcu);
+}
+
+static void tt_global_entry_free_ref(struct tt_global_entry *tt_global_entry)
+{
+       if (atomic_dec_and_test(&tt_global_entry->refcount))
+               kfree_rcu(tt_global_entry, rcu);
+}
+
 static void tt_local_event(struct bat_priv *bat_priv, uint8_t op,
-                          const uint8_t *addr, uint8_t roaming)
+                          const uint8_t *addr, bool roaming)
 {
        struct tt_change_node *tt_change_node;
 
@@ -171,21 +189,19 @@ static int tt_local_init(struct bat_priv *bat_priv)
 void tt_local_add(struct net_device *soft_iface, const uint8_t *addr)
 {
        struct bat_priv *bat_priv = netdev_priv(soft_iface);
-       struct tt_local_entry *tt_local_entry;
-       struct tt_global_entry *tt_global_entry;
-       uint8_t roam_addr[ETH_ALEN];
+       struct tt_local_entry *tt_local_entry = NULL;
+       struct tt_global_entry *tt_global_entry = NULL;
 
-       spin_lock_bh(&bat_priv->tt_lhash_lock);
        tt_local_entry = tt_local_hash_find(bat_priv, addr);
 
        if (tt_local_entry) {
                tt_local_entry->last_seen = jiffies;
-               goto unlock;
+               goto out;
        }
 
        tt_local_entry = kmalloc(sizeof(*tt_local_entry), GFP_ATOMIC);
        if (!tt_local_entry)
-               goto unlock;
+               goto out;
 
        tt_local_event(bat_priv, NO_FLAGS, addr, false);
 
@@ -195,6 +211,7 @@ void tt_local_add(struct net_device *soft_iface, const uint8_t *addr)
 
        memcpy(tt_local_entry->addr, addr, ETH_ALEN);
        tt_local_entry->last_seen = jiffies;
+       atomic_set(&tt_local_entry->refcount, 2);
 
        /* the batman interface mac address should never be purged */
        if (compare_eth(addr, soft_iface->dev_addr))
@@ -204,30 +221,26 @@ void tt_local_add(struct net_device *soft_iface, const uint8_t *addr)
 
        hash_add(bat_priv->tt_local_hash, compare_ltt, choose_orig,
                 tt_local_entry, &tt_local_entry->hash_entry);
+
        atomic_inc(&bat_priv->num_local_tt);
-       spin_unlock_bh(&bat_priv->tt_lhash_lock);
 
        /* remove address from global hash if present */
-       spin_lock_bh(&bat_priv->tt_ghash_lock);
-
        tt_global_entry = tt_global_hash_find(bat_priv, addr);
 
        /* Check whether it is a roaming! */
        if (tt_global_entry) {
-               memcpy(roam_addr, tt_global_entry->addr, ETH_ALEN);
                /* This node is probably going to update its tt table */
                tt_global_entry->orig_node->tt_poss_change = true;
                _tt_global_del(bat_priv, tt_global_entry,
                               "local tt received");
-               spin_unlock_bh(&bat_priv->tt_ghash_lock);
                send_roam_adv(bat_priv, tt_global_entry->addr,
-                       tt_global_entry->orig_node);
-       } else
-               spin_unlock_bh(&bat_priv->tt_ghash_lock);
-
-       return;
-unlock:
-       spin_unlock_bh(&bat_priv->tt_lhash_lock);
+                             tt_global_entry->orig_node);
+       }
+out:
+       if (tt_local_entry)
+               tt_local_entry_free_ref(tt_local_entry);
+       if (tt_global_entry)
+               tt_global_entry_free_ref(tt_global_entry);
 }
 
 int tt_changes_fill_buffer(struct bat_priv *bat_priv,
@@ -309,8 +322,6 @@ int tt_local_seq_print_text(struct seq_file *seq, void *offset)
                   "announced via TT (TTVN: %u):\n",
                   net_dev->name, (uint8_t)atomic_read(&bat_priv->ttvn));
 
-       spin_lock_bh(&bat_priv->tt_lhash_lock);
-
        buf_size = 1;
        /* Estimate length for: " * xx:xx:xx:xx:xx:xx\n" */
        for (i = 0; i < hash->size; i++) {
@@ -324,7 +335,6 @@ int tt_local_seq_print_text(struct seq_file *seq, void *offset)
 
        buff = kmalloc(buf_size, GFP_ATOMIC);
        if (!buff) {
-               spin_unlock_bh(&bat_priv->tt_lhash_lock);
                ret = -ENOMEM;
                goto out;
        }
@@ -344,8 +354,6 @@ int tt_local_seq_print_text(struct seq_file *seq, void *offset)
                rcu_read_unlock();
        }
 
-       spin_unlock_bh(&bat_priv->tt_lhash_lock);
-
        seq_printf(seq, "%s", buff);
        kfree(buff);
 out:
@@ -354,15 +362,6 @@ out:
        return ret;
 }
 
-static void tt_local_entry_free(struct hlist_node *node, void *arg)
-{
-       struct bat_priv *bat_priv = arg;
-       void *data = container_of(node, struct tt_local_entry, hash_entry);
-
-       kfree(data);
-       atomic_dec(&bat_priv->num_local_tt);
-}
-
 static void tt_local_del(struct bat_priv *bat_priv,
                         struct tt_local_entry *tt_local_entry,
                         const char *message)
@@ -375,23 +374,24 @@ static void tt_local_del(struct bat_priv *bat_priv,
        hash_remove(bat_priv->tt_local_hash, compare_ltt, choose_orig,
                    tt_local_entry->addr);
 
-       tt_local_entry_free(&tt_local_entry->hash_entry, bat_priv);
+       tt_local_entry_free_ref(tt_local_entry);
 }
 
 void tt_local_remove(struct bat_priv *bat_priv, const uint8_t *addr,
                     const char *message, bool roaming)
 {
-       struct tt_local_entry *tt_local_entry;
+       struct tt_local_entry *tt_local_entry = NULL;
 
-       spin_lock_bh(&bat_priv->tt_lhash_lock);
        tt_local_entry = tt_local_hash_find(bat_priv, addr);
 
-       if (tt_local_entry) {
-               tt_local_event(bat_priv, TT_CHANGE_DEL, tt_local_entry->addr,
-                              roaming);
-               tt_local_del(bat_priv, tt_local_entry, message);
-       }
-       spin_unlock_bh(&bat_priv->tt_lhash_lock);
+       if (!tt_local_entry)
+               goto out;
+
+       tt_local_event(bat_priv, TT_CHANGE_DEL, tt_local_entry->addr, roaming);
+       tt_local_del(bat_priv, tt_local_entry, message);
+out:
+       if (tt_local_entry)
+               tt_local_entry_free_ref(tt_local_entry);
 }
 
 static void tt_local_purge(struct bat_priv *bat_priv)
@@ -400,40 +400,45 @@ static void tt_local_purge(struct bat_priv *bat_priv)
        struct tt_local_entry *tt_local_entry;
        struct hlist_node *node, *node_tmp;
        struct hlist_head *head;
+       spinlock_t *list_lock; /* protects write access to the hash lists */
        int i;
 
-       spin_lock_bh(&bat_priv->tt_lhash_lock);
-
        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_local_entry, node, node_tmp,
                                          head, hash_entry) {
                        if (tt_local_entry->never_purge)
                                continue;
 
                        if (!is_out_of_time(tt_local_entry->last_seen,
-                                          TT_LOCAL_TIMEOUT * 1000))
+                                           TT_LOCAL_TIMEOUT * 1000))
                                continue;
 
                        tt_local_event(bat_priv, TT_CHANGE_DEL,
                                       tt_local_entry->addr, false);
-                       tt_local_del(bat_priv, tt_local_entry,
-                                    "address timed out");
+                       atomic_dec(&bat_priv->num_local_tt);
+                       bat_dbg(DBG_TT, bat_priv, "Deleting local "
+                               "tt entry (%pM): timed out\n",
+                               tt_local_entry->addr);
+                       hlist_del_rcu(node);
+                       tt_local_entry_free_ref(tt_local_entry);
                }
+               spin_unlock_bh(list_lock);
        }
 
-       spin_unlock_bh(&bat_priv->tt_lhash_lock);
 }
 
 static void tt_local_table_free(struct bat_priv *bat_priv)
 {
        struct hashtable_t *hash;
-       int i;
        spinlock_t *list_lock; /* protects write access to the hash lists */
-       struct hlist_head *head;
-       struct hlist_node *node, *node_tmp;
        struct tt_local_entry *tt_local_entry;
+       struct hlist_node *node, *node_tmp;
+       struct hlist_head *head;
+       int i;
 
        if (!bat_priv->tt_local_hash)
                return;
@@ -448,7 +453,7 @@ static void tt_local_table_free(struct bat_priv *bat_priv)
                hlist_for_each_entry_safe(tt_local_entry, node, node_tmp,
                                          head, hash_entry) {
                        hlist_del_rcu(node);
-                       kfree(tt_local_entry);
+                       tt_local_entry_free_ref(tt_local_entry);
                }
                spin_unlock_bh(list_lock);
        }
@@ -492,10 +497,9 @@ int tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node,
                  const unsigned char *tt_addr, uint8_t ttvn, bool roaming)
 {
        struct tt_global_entry *tt_global_entry;
-       struct tt_local_entry *tt_local_entry;
        struct orig_node *orig_node_tmp;
+       int ret = 0;
 
-       spin_lock_bh(&bat_priv->tt_ghash_lock);
        tt_global_entry = tt_global_hash_find(bat_priv, tt_addr);
 
        if (!tt_global_entry) {
@@ -503,7 +507,8 @@ int tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node,
                        kmalloc(sizeof(*tt_global_entry),
                                GFP_ATOMIC);
                if (!tt_global_entry)
-                       goto unlock;
+                       goto out;
+
                memcpy(tt_global_entry->addr, tt_addr, ETH_ALEN);
                /* Assign the new orig_node */
                atomic_inc(&orig_node->refcount);
@@ -511,10 +516,12 @@ int tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node,
                tt_global_entry->ttvn = ttvn;
                tt_global_entry->flags = NO_FLAGS;
                tt_global_entry->roam_at = 0;
-               atomic_inc(&orig_node->tt_size);
+               atomic_set(&tt_global_entry->refcount, 2);
+
                hash_add(bat_priv->tt_global_hash, compare_gtt,
                         choose_orig, tt_global_entry,
                         &tt_global_entry->hash_entry);
+               atomic_inc(&orig_node->tt_size);
        } else {
                if (tt_global_entry->orig_node != orig_node) {
                        atomic_dec(&tt_global_entry->orig_node->tt_size);
@@ -529,25 +536,18 @@ int tt_global_add(struct bat_priv *bat_priv, struct orig_node *orig_node,
                tt_global_entry->roam_at = 0;
        }
 
-       spin_unlock_bh(&bat_priv->tt_ghash_lock);
-
        bat_dbg(DBG_TT, bat_priv,
                "Creating new global tt entry: %pM (via %pM)\n",
                tt_global_entry->addr, orig_node->orig);
 
        /* remove address from local hash if present */
-       spin_lock_bh(&bat_priv->tt_lhash_lock);
-       tt_local_entry = tt_local_hash_find(bat_priv, tt_addr);
-
-       if (tt_local_entry)
-               tt_local_remove(bat_priv, tt_global_entry->addr,
-                               "global tt received", roaming);
-
-       spin_unlock_bh(&bat_priv->tt_lhash_lock);
-       return 1;
-unlock:
-       spin_unlock_bh(&bat_priv->tt_ghash_lock);
-       return 0;
+       tt_local_remove(bat_priv, tt_global_entry->addr,
+                       "global tt received", roaming);
+       ret = 1;
+out:
+       if (tt_global_entry)
+               tt_global_entry_free_ref(tt_global_entry);
+       return ret;
 }
 
 int tt_global_seq_print_text(struct seq_file *seq, void *offset)
@@ -584,8 +584,6 @@ int tt_global_seq_print_text(struct seq_file *seq, void *offset)
        seq_printf(seq, "       %-13s %s       %-15s %s\n",
                   "Client", "(TTVN)", "Originator", "(Curr TTVN)");
 
-       spin_lock_bh(&bat_priv->tt_ghash_lock);
-
        buf_size = 1;
        /* Estimate length for: " * xx:xx:xx:xx:xx:xx (ttvn) via
         * xx:xx:xx:xx:xx:xx (cur_ttvn)\n"*/
@@ -600,10 +598,10 @@ int tt_global_seq_print_text(struct seq_file *seq, void *offset)
 
        buff = kmalloc(buf_size, GFP_ATOMIC);
        if (!buff) {
-               spin_unlock_bh(&bat_priv->tt_ghash_lock);
                ret = -ENOMEM;
                goto out;
        }
+
        buff[0] = '\0';
        pos = 0;
 
@@ -625,8 +623,6 @@ int tt_global_seq_print_text(struct seq_file *seq, void *offset)
                rcu_read_unlock();
        }
 
-       spin_unlock_bh(&bat_priv->tt_ghash_lock);
-
        seq_printf(seq, "%s", buff);
        kfree(buff);
 out:
@@ -640,7 +636,7 @@ static void _tt_global_del(struct bat_priv *bat_priv,
                           const char *message)
 {
        if (!tt_global_entry)
-               return;
+               goto out;
 
        bat_dbg(DBG_TT, bat_priv,
                "Deleting global tt entry %pM (via %pM): %s\n",
@@ -648,31 +644,35 @@ static void _tt_global_del(struct bat_priv *bat_priv,
                message);
 
        atomic_dec(&tt_global_entry->orig_node->tt_size);
+
        hash_remove(bat_priv->tt_global_hash, compare_gtt, choose_orig,
                    tt_global_entry->addr);
-       kfree(tt_global_entry);
+out:
+       if (tt_global_entry)
+               tt_global_entry_free_ref(tt_global_entry);
 }
 
 void tt_global_del(struct bat_priv *bat_priv,
                   struct orig_node *orig_node, const unsigned char *addr,
                   const char *message, bool roaming)
 {
-       struct tt_global_entry *tt_global_entry;
+       struct tt_global_entry *tt_global_entry = NULL;
 
-       spin_lock_bh(&bat_priv->tt_ghash_lock);
        tt_global_entry = tt_global_hash_find(bat_priv, addr);
+       if (!tt_global_entry)
+               goto out;
 
-       if (tt_global_entry && tt_global_entry->orig_node == orig_node) {
+       if (tt_global_entry->orig_node == orig_node) {
                if (roaming) {
                        tt_global_entry->flags |= TT_CLIENT_ROAM;
                        tt_global_entry->roam_at = jiffies;
                        goto out;
                }
-               atomic_dec(&orig_node->tt_size);
                _tt_global_del(bat_priv, tt_global_entry, message);
        }
 out:
-       spin_unlock_bh(&bat_priv->tt_ghash_lock);
+       if (tt_global_entry)
+               tt_global_entry_free_ref(tt_global_entry);
 }
 
 void tt_global_del_orig(struct bat_priv *bat_priv,
@@ -683,30 +683,28 @@ void tt_global_del_orig(struct bat_priv *bat_priv,
        struct hashtable_t *hash = bat_priv->tt_global_hash;
        struct hlist_node *node, *safe;
        struct hlist_head *head;
+       spinlock_t *list_lock; /* protects write access to the hash lists */
 
-       if (!bat_priv->tt_global_hash)
-               return;
-
-       spin_lock_bh(&bat_priv->tt_ghash_lock);
        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_global_entry, node, safe,
                                         head, hash_entry) {
-                       if (tt_global_entry->orig_node == orig_node)
-                               _tt_global_del(bat_priv, tt_global_entry,
-                                              message);
+                       if (tt_global_entry->orig_node == orig_node) {
+                               bat_dbg(DBG_TT, bat_priv,
+                                       "Deleting global tt entry %pM "
+                                       "(via %pM): originator time out\n",
+                                       tt_global_entry->addr,
+                                       tt_global_entry->orig_node->orig);
+                               hlist_del_rcu(node);
+                               tt_global_entry_free_ref(tt_global_entry);
+                       }
                }
+               spin_unlock_bh(list_lock);
        }
        atomic_set(&orig_node->tt_size, 0);
-
-       spin_unlock_bh(&bat_priv->tt_ghash_lock);
-}
-
-static void tt_global_entry_free(struct hlist_node *node, void *arg)
-{
-       void *data = container_of(node, struct tt_global_entry, hash_entry);
-       kfree(data);
 }
 
 static void tt_global_roam_purge(struct bat_priv *bat_priv)
@@ -715,13 +713,14 @@ static void tt_global_roam_purge(struct bat_priv *bat_priv)
        struct tt_global_entry *tt_global_entry;
        struct hlist_node *node, *node_tmp;
        struct hlist_head *head;
+       spinlock_t *list_lock; /* protects write access to the hash lists */
        int i;
 
-       spin_lock_bh(&bat_priv->tt_ghash_lock);
-
        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_global_entry, node, node_tmp,
                                          head, hash_entry) {
                        if (!(tt_global_entry->flags & TT_CLIENT_ROAM))
@@ -730,20 +729,47 @@ static void tt_global_roam_purge(struct bat_priv *bat_priv)
                                            TT_CLIENT_ROAM_TIMEOUT * 1000))
                                continue;
 
-                       _tt_global_del(bat_priv, tt_global_entry,
-                                      "Roaming timeout");
+                       bat_dbg(DBG_TT, bat_priv, "Deleting global "
+                               "tt entry (%pM): Roaming timeout\n",
+                               tt_global_entry->addr);
+                       atomic_dec(&tt_global_entry->orig_node->tt_size);
+                       hlist_del_rcu(node);
+                       tt_global_entry_free_ref(tt_global_entry);
                }
+               spin_unlock_bh(list_lock);
        }
 
-       spin_unlock_bh(&bat_priv->tt_ghash_lock);
 }
 
 static void tt_global_table_free(struct bat_priv *bat_priv)
 {
+       struct hashtable_t *hash;
+       spinlock_t *list_lock; /* protects write access to the hash lists */
+       struct tt_global_entry *tt_global_entry;
+       struct hlist_node *node, *node_tmp;
+       struct hlist_head *head;
+       int i;
+
        if (!bat_priv->tt_global_hash)
                return;
 
-       hash_delete(bat_priv->tt_global_hash, tt_global_entry_free, NULL);
+       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_global_entry, node, node_tmp,
+                                         head, hash_entry) {
+                       hlist_del_rcu(node);
+                       tt_global_entry_free_ref(tt_global_entry);
+               }
+               spin_unlock_bh(list_lock);
+       }
+
+       hash_destroy(hash);
+
        bat_priv->tt_global_hash = NULL;
 }
 
@@ -753,19 +779,19 @@ struct orig_node *transtable_search(struct bat_priv *bat_priv,
        struct tt_global_entry *tt_global_entry;
        struct orig_node *orig_node = NULL;
 
-       spin_lock_bh(&bat_priv->tt_ghash_lock);
        tt_global_entry = tt_global_hash_find(bat_priv, addr);
 
        if (!tt_global_entry)
                goto out;
 
        if (!atomic_inc_not_zero(&tt_global_entry->orig_node->refcount))
-               goto out;
+               goto free_tt;
 
        orig_node = tt_global_entry->orig_node;
 
+free_tt:
+       tt_global_entry_free_ref(tt_global_entry);
 out:
-       spin_unlock_bh(&bat_priv->tt_ghash_lock);
        return orig_node;
 }
 
@@ -828,7 +854,6 @@ uint16_t tt_local_crc(struct bat_priv *bat_priv)
                                                   tt_local_entry->addr[j]);
                        total ^= total_one;
                }
-
                rcu_read_unlock();
        }
 
@@ -1371,15 +1396,17 @@ void tt_update_changes(struct bat_priv *bat_priv, struct orig_node *orig_node,
 
 bool is_my_client(struct bat_priv *bat_priv, const uint8_t *addr)
 {
-       struct tt_local_entry *tt_local_entry;
+       struct tt_local_entry *tt_local_entry = NULL;
+       bool ret = false;
 
-       spin_lock_bh(&bat_priv->tt_lhash_lock);
        tt_local_entry = tt_local_hash_find(bat_priv, addr);
-       spin_unlock_bh(&bat_priv->tt_lhash_lock);
-
+       if (!tt_local_entry)
+               goto out;
+       ret = true;
+out:
        if (tt_local_entry)
-               return true;
-       return false;
+               tt_local_entry_free_ref(tt_local_entry);
+       return ret;
 }
 
 void handle_tt_response(struct bat_priv *bat_priv,
@@ -1416,9 +1443,7 @@ void handle_tt_response(struct bat_priv *bat_priv,
        spin_unlock_bh(&bat_priv->tt_req_list_lock);
 
        /* Recalculate the CRC for this orig_node and store it */
-       spin_lock_bh(&bat_priv->tt_ghash_lock);
        orig_node->tt_crc = tt_global_crc(bat_priv, orig_node);
-       spin_unlock_bh(&bat_priv->tt_ghash_lock);
        /* Roaming phase is over: tables are in sync again. I can
         * unset the flag */
        orig_node->tt_poss_change = false;

diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 9c84fa9f096844609fafc6abb0021312b55709d4..11e8569a8ca715ec9770a0cde7cc53f4e569925b 100644 (file)
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -184,8 +184,6 @@ struct bat_priv {
        spinlock_t forw_bat_list_lock; /* protects forw_bat_list */
        spinlock_t forw_bcast_list_lock; /* protects  */
        spinlock_t tt_changes_list_lock; /* protects tt_changes */
-       spinlock_t tt_lhash_lock; /* protects tt_local_hash */
-       spinlock_t tt_ghash_lock; /* protects tt_global_hash */
        spinlock_t tt_req_list_lock; /* protects tt_req_list */
        spinlock_t tt_roam_list_lock; /* protects tt_roam_list */
        spinlock_t gw_list_lock; /* protects gw_list and curr_gw */
@@ -226,6 +224,8 @@ struct tt_local_entry {
        uint8_t addr[ETH_ALEN];
        unsigned long last_seen;
        char never_purge;
+       atomic_t refcount;
+       struct rcu_head rcu;
        struct hlist_node hash_entry;
 };
 
@@ -235,6 +235,8 @@ struct tt_global_entry {
        uint8_t ttvn;
        uint8_t flags; /* only TT_GLOBAL_ROAM is used */
        unsigned long roam_at; /* time at which TT_GLOBAL_ROAM was set */
+       atomic_t refcount;
+       struct rcu_head rcu;
        struct hlist_node hash_entry; /* entry in the global table */
 };
 

diff --git a/net/batman-adv/vis.c b/net/batman-adv/vis.c
index 355c6e590b0cc01f60f130fcf49bde0566966e2b..8a1b98589d7627de6faf6cafc1f14f0bf416bed2 100644 (file)
--- a/net/batman-adv/vis.c
+++ b/net/batman-adv/vis.c
@@ -665,11 +665,12 @@ next:
 
        hash = bat_priv->tt_local_hash;
 
-       spin_lock_bh(&bat_priv->tt_lhash_lock);
        for (i = 0; i < hash->size; i++) {
                head = &hash->table[i];
 
-               hlist_for_each_entry(tt_local_entry, node, head, hash_entry) {
+               rcu_read_lock();
+               hlist_for_each_entry_rcu(tt_local_entry, node, head,
+                                        hash_entry) {
                        entry = (struct vis_info_entry *)
                                        skb_put(info->skb_packet,
                                                sizeof(*entry));
@@ -678,14 +679,12 @@ next:
                        entry->quality = 0; /* 0 means TT */
                        packet->entries++;
 
-                       if (vis_packet_full(info)) {
-                               spin_unlock_bh(&bat_priv->tt_lhash_lock);
-                               return 0;
-                       }
+                       if (vis_packet_full(info))
+                               goto unlock;
                }
+               rcu_read_unlock();
        }
 
-       spin_unlock_bh(&bat_priv->tt_lhash_lock);
        return 0;
 
 unlock: