int batadv_hardif_min_mtu(struct net_device *soft_iface)
{
- const struct batadv_priv *bat_priv = netdev_priv(soft_iface);
+ struct batadv_priv *bat_priv = netdev_priv(soft_iface);
const struct batadv_hard_iface *hard_iface;
- /* allow big frames if all devices are capable to do so
- * (have MTU > 1500 + batadv_max_header_len())
- */
int min_mtu = ETH_DATA_LEN;
- int max_header_len = batadv_max_header_len();
-
- if (atomic_read(&bat_priv->fragmentation))
- goto out;
rcu_read_lock();
list_for_each_entry_rcu(hard_iface, &batadv_hardif_list, list) {
if (hard_iface->soft_iface != soft_iface)
continue;
- min_mtu = min_t(int, hard_iface->net_dev->mtu - max_header_len,
- min_mtu);
+ min_mtu = min_t(int, hard_iface->net_dev->mtu, min_mtu);
}
rcu_read_unlock();
+
+ atomic_set(&bat_priv->packet_size_max, min_mtu);
+
+ if (atomic_read(&bat_priv->fragmentation) == 0)
+ goto out;
+
+ /* with fragmentation enabled the maximum size of internally generated
+ * packets such as translation table exchanges or tvlv containers, etc
+ * has to be calculated
+ */
+ min_mtu = min_t(int, min_mtu, BATADV_FRAG_MAX_FRAG_SIZE);
+ min_mtu -= sizeof(struct batadv_frag_packet);
+ min_mtu *= BATADV_FRAG_MAX_FRAGMENTS;
+ atomic_set(&bat_priv->packet_size_max, min_mtu);
+
+ /* with fragmentation enabled we can fragment external packets easily */
+ min_mtu = min_t(int, min_mtu, ETH_DATA_LEN);
+
out:
- return min_mtu;
+ return min_mtu - batadv_max_header_len();
}
/* adjusts the MTU if a new interface with a smaller MTU appeared. */
void batadv_update_min_mtu(struct net_device *soft_iface)
{
- int min_mtu;
+ soft_iface->mtu = batadv_hardif_min_mtu(soft_iface);
- min_mtu = batadv_hardif_min_mtu(soft_iface);
- if (soft_iface->mtu != min_mtu)
- soft_iface->mtu = min_mtu;
+ /* Check if the local translate table should be cleaned up to match a
+ * new (and smaller) MTU.
+ */
+ batadv_tt_local_resize_to_mtu(soft_iface);
}
static void
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
+ *
+ * Returns local translation table size in bytes.
+ */
+static int batadv_tt_local_table_transmit_size(struct batadv_priv *bat_priv)
+{
+ uint16_t num_vlan = 0, 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)
* @vid: VLAN identifier
* @ifindex: index of the interface where the client is connected to (useful to
* identify wireless clients)
+ *
+ * Returns true if the client was successfully added, false otherwise.
*/
-void batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr,
+bool batadv_tt_local_add(struct net_device *soft_iface, const uint8_t *addr,
unsigned short vid, int ifindex)
{
struct batadv_priv *bat_priv = netdev_priv(soft_iface);
struct batadv_tt_global_entry *tt_global;
struct hlist_head *head;
struct batadv_tt_orig_list_entry *orig_entry;
- int hash_added;
- bool roamed_back = false;
+ int hash_added, table_size, packet_size_max;
+ bool ret = false, roamed_back = false;
tt_local = batadv_tt_local_hash_find(bat_priv, addr, vid);
tt_global = batadv_tt_global_hash_find(bat_priv, addr, vid);
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 = kmalloc(sizeof(*tt_local), GFP_ATOMIC);
if (!tt_local)
goto out;
}
}
+ ret = true;
+
out:
if (tt_local)
batadv_tt_local_entry_free_ref(tt_local);
if (tt_global)
batadv_tt_global_entry_free_ref(tt_global);
+ return ret;
}
/**
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)
+ struct hlist_head *head,
+ int timeout)
{
struct batadv_tt_local_entry *tt_local_entry;
struct batadv_tt_common_entry *tt_common_entry;
if (tt_local_entry->common.flags & BATADV_TT_CLIENT_PENDING)
continue;
- if (!batadv_has_timed_out(tt_local_entry->last_seen,
- BATADV_TT_LOCAL_TIMEOUT))
+ if (!batadv_has_timed_out(tt_local_entry->last_seen, timeout))
continue;
batadv_tt_local_set_pending(bat_priv, tt_local_entry,
}
}
-static void batadv_tt_local_purge(struct batadv_priv *bat_priv)
+/**
+ * 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;
list_lock = &hash->list_locks[i];
spin_lock_bh(list_lock);
- batadv_tt_local_purge_list(bat_priv, head);
+ batadv_tt_local_purge_list(bat_priv, head, timeout);
spin_unlock_bh(list_lock);
}
}
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;
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_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);
}
/**
- * batadv_tt_local_commit_changes - commit all pending local tt changes which
- * have been queued in the time since the last commit
+ * 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.
*/
-void batadv_tt_local_commit_changes(struct batadv_priv *bat_priv)
+static void batadv_tt_local_commit_changes_nolock(struct batadv_priv *bat_priv)
{
- spin_lock_bh(&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);
- goto out;
+ return;
}
batadv_tt_local_set_flags(bat_priv, BATADV_TT_CLIENT_NEW, false, true);
/* reset the sending counter */
atomic_set(&bat_priv->tt.ogm_append_cnt, BATADV_TT_OGM_APPEND_MAX);
batadv_tt_tvlv_container_update(bat_priv);
+}
-out:
+/**
+ * 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);
}
return ret;
}
+/**
+ * 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
projects / users / willy / pagecache.git / commitdiff