batman-adv: tvlv - convert tt data sent within OGMs

The translation table meta data (version number, crc checksum, etc)
as well as the translation table diff propgated within OGMs now uses
the newly introduced tvlv infrastructure.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>

1 files changed, 130 insertions, 110 deletions

diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index 34510f3..3fac67f 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -180,11 +180,11 @@ static void batadv_tt_local_event(struct batadv_priv *bat_priv,
 	bool del_op_requested, del_op_entry;
 
 	tt_change_node = kmalloc(sizeof(*tt_change_node), GFP_ATOMIC);
-
 	if (!tt_change_node)
 		return;
 
 	tt_change_node->change.flags = flags;
+	tt_change_node->change.reserved = 0;
 	memcpy(tt_change_node->change.addr, common->addr, ETH_ALEN);
 
 	del_op_requested = flags & BATADV_TT_CLIENT_DEL;
@@ -376,71 +376,52 @@ out:
 		batadv_tt_global_entry_free_ref(tt_global);
 }
 
-static void batadv_tt_realloc_packet_buff(unsigned char **packet_buff,
-					  int *packet_buff_len,
-					  int min_packet_len,
-					  int new_packet_len)
-{
-	unsigned char *new_buff;
-
-	new_buff = kmalloc(new_packet_len, GFP_ATOMIC);
-
-	/* keep old buffer if kmalloc should fail */
-	if (new_buff) {
-		memcpy(new_buff, *packet_buff, min_packet_len);
-		kfree(*packet_buff);
-		*packet_buff = new_buff;
-		*packet_buff_len = new_packet_len;
-	}
-}
-
-static void batadv_tt_prepare_packet_buff(struct batadv_priv *bat_priv,
-					  unsigned char **packet_buff,
-					  int *packet_buff_len,
-					  int min_packet_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)
 {
-	int req_len;
+	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 = 0, tt_change_len = 0;
+	int tt_diff_entries_num = 0, tt_diff_entries_count = 0;
 
-	req_len = min_packet_len;
-	req_len += batadv_tt_len(atomic_read(&bat_priv->tt.local_changes));
+	tt_diff_len += batadv_tt_len(atomic_read(&bat_priv->tt.local_changes));
 
 	/* 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 (req_len > bat_priv->soft_iface->mtu)
-		req_len = min_packet_len;
+	if (tt_diff_len > bat_priv->soft_iface->mtu)
+		tt_diff_len = 0;
 
-	batadv_tt_realloc_packet_buff(packet_buff, packet_buff_len,
-				      min_packet_len, req_len);
-}
-
-static int batadv_tt_changes_fill_buff(struct batadv_priv *bat_priv,
-				       unsigned char **packet_buff,
-				       int *packet_buff_len,
-				       int min_packet_len)
-{
-	struct batadv_tt_change_node *entry, *safe;
-	int count = 0, tot_changes = 0, new_len;
-	unsigned char *tt_buff;
+	tt_data = kzalloc(sizeof(*tt_data) + tt_diff_len, GFP_ATOMIC);
+	if (!tt_data)
+		return;
 
-	batadv_tt_prepare_packet_buff(bat_priv, packet_buff,
-				      packet_buff_len, min_packet_len);
+	tt_data->flags = BATADV_TT_OGM_DIFF;
+	tt_data->ttvn = atomic_read(&bat_priv->tt.vn);
+	tt_data->crc = htons(bat_priv->tt.local_crc);
 
-	new_len = *packet_buff_len - min_packet_len;
-	tt_buff = *packet_buff + min_packet_len;
+	if (tt_diff_len == 0)
+		goto container_register;
 
-	if (new_len > 0)
-		tot_changes = new_len / batadv_tt_len(1);
+	tt_diff_entries_num = tt_diff_len / batadv_tt_len(1);
 
 	spin_lock_bh(&bat_priv->tt.changes_list_lock);
 	atomic_set(&bat_priv->tt.local_changes, 0);
 
+	tt_change = (struct batadv_tvlv_tt_change *)(tt_data + 1);
+
 	list_for_each_entry_safe(entry, safe, &bat_priv->tt.changes_list,
 				 list) {
-		if (count < tot_changes) {
-			memcpy(tt_buff + batadv_tt_len(count),
-			       &entry->change, sizeof(struct batadv_tt_change));
-			count++;
+		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);
 		kfree(entry);
@@ -452,20 +433,25 @@ static int batadv_tt_changes_fill_buff(struct batadv_priv *bat_priv,
 	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 (new_len > 0) {
+	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 = kmalloc(new_len, GFP_ATOMIC);
+		bat_priv->tt.last_changeset = kzalloc(tt_diff_len, GFP_ATOMIC);
 		if (bat_priv->tt.last_changeset) {
-			memcpy(bat_priv->tt.last_changeset, tt_buff, new_len);
-			bat_priv->tt.last_changeset_len = new_len;
+			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);
 
-	return count;
+container_register:
+	batadv_tvlv_container_register(bat_priv, BATADV_TVLV_TT, 1, tt_data,
+				       sizeof(*tt_data) + tt_change_len);
+	kfree(tt_data);
 }
 
 int batadv_tt_local_seq_print_text(struct seq_file *seq, void *offset)
@@ -1504,7 +1490,7 @@ static void batadv_tt_req_list_free(struct batadv_priv *bat_priv)
 static void batadv_tt_save_orig_buffer(struct batadv_priv *bat_priv,
 				       struct batadv_orig_node *orig_node,
 				       const unsigned char *tt_buff,
-				       uint8_t tt_num_changes)
+				       uint16_t tt_num_changes)
 {
 	uint16_t tt_buff_len = batadv_tt_len(tt_num_changes);
 
@@ -2126,25 +2112,6 @@ out:
 		batadv_orig_node_free_ref(orig_node);
 }
 
-int batadv_tt_init(struct batadv_priv *bat_priv)
-{
-	int ret;
-
-	ret = batadv_tt_local_init(bat_priv);
-	if (ret < 0)
-		return ret;
-
-	ret = batadv_tt_global_init(bat_priv);
-	if (ret < 0)
-		return ret;
-
-	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;
-}
-
 static void batadv_tt_roam_list_free(struct batadv_priv *bat_priv)
 {
 	struct batadv_tt_roam_node *node, *safe;
@@ -2297,6 +2264,9 @@ static void batadv_tt_purge(struct work_struct *work)
 
 void batadv_tt_free(struct batadv_priv *bat_priv)
 {
+	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);
@@ -2384,14 +2354,20 @@ static void batadv_tt_local_purge_pending_clients(struct batadv_priv *bat_priv)
 	}
 }
 
-static int batadv_tt_commit_changes(struct batadv_priv *bat_priv,
-				    unsigned char **packet_buff,
-				    int *packet_buff_len, int packet_min_len)
+/**
+ * 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)
 {
 	uint16_t changed_num = 0;
 
-	if (atomic_read(&bat_priv->tt.local_changes) < 1)
-		return -ENOENT;
+	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;
+	}
 
 	changed_num = batadv_tt_set_flags(bat_priv->tt.local_hash,
 					  BATADV_TT_CLIENT_NEW, false);
@@ -2409,32 +2385,7 @@ static int batadv_tt_commit_changes(struct batadv_priv *bat_priv,
 
 	/* reset the sending counter */
 	atomic_set(&bat_priv->tt.ogm_append_cnt, BATADV_TT_OGM_APPEND_MAX);
-
-	return batadv_tt_changes_fill_buff(bat_priv, packet_buff,
-					   packet_buff_len, packet_min_len);
-}
-
-/* when calling this function (hard_iface == primary_if) has to be true */
-int batadv_tt_append_diff(struct batadv_priv *bat_priv,
-			  unsigned char **packet_buff, int *packet_buff_len,
-			  int packet_min_len)
-{
-	int tt_num_changes;
-
-	/* if at least one change happened */
-	tt_num_changes = batadv_tt_commit_changes(bat_priv, packet_buff,
-						  packet_buff_len,
-						  packet_min_len);
-
-	/* if the changes have been sent often enough */
-	if ((tt_num_changes < 0) &&
-	    (!batadv_atomic_dec_not_zero(&bat_priv->tt.ogm_append_cnt))) {
-		batadv_tt_realloc_packet_buff(packet_buff, packet_buff_len,
-					      packet_min_len, packet_min_len);
-		tt_num_changes = 0;
-	}
-
-	return tt_num_changes;
+	batadv_tt_tvlv_container_update(bat_priv);
 }
 
 bool batadv_is_ap_isolated(struct batadv_priv *bat_priv, uint8_t *src,
@@ -2468,10 +2419,21 @@ out:
 	return ret;
 }
 
-void batadv_tt_update_orig(struct batadv_priv *bat_priv,
-			   struct batadv_orig_node *orig_node,
-			   const unsigned char *tt_buff, uint8_t tt_num_changes,
-			   uint8_t ttvn, uint16_t tt_crc)
+/**
+ * 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: the orig_node of the ogm
+ * @tt_buff: buffer holding the tt information
+ * @tt_num_changes: number of tt changes inside the tt buffer
+ * @ttvn: translation table version number of this changeset
+ * @tt_crc: crc16 checksum of orig node's translation table
+ */
+static void batadv_tt_update_orig(struct batadv_priv *bat_priv,
+				  struct batadv_orig_node *orig_node,
+				  const unsigned char *tt_buff,
+				  uint16_t tt_num_changes, uint8_t ttvn,
+				  uint16_t tt_crc)
 {
 	uint8_t orig_ttvn = (uint8_t)atomic_read(&orig_node->last_ttvn);
 	bool full_table = true;
@@ -2605,3 +2567,61 @@ bool batadv_tt_add_temporary_global_entry(struct batadv_priv *bat_priv,
 out:
 	return ret;
 }
+
+/**
+ * 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,
+					  uint8_t flags,
+					  void *tvlv_value,
+					  uint16_t tvlv_value_len)
+{
+	struct batadv_tvlv_tt_data *tt_data;
+	uint16_t num_entries;
+
+	if (tvlv_value_len < sizeof(*tt_data))
+		return;
+
+	tt_data = (struct batadv_tvlv_tt_data *)tvlv_value;
+	tvlv_value_len -= sizeof(*tt_data);
+
+	num_entries = tvlv_value_len / batadv_tt_len(1);
+
+	batadv_tt_update_orig(bat_priv, orig,
+			      (unsigned char *)(tt_data + 1),
+			      num_entries, tt_data->ttvn, ntohs(tt_data->crc));
+}
+
+/**
+ * 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;
+
+	ret = batadv_tt_local_init(bat_priv);
+	if (ret < 0)
+		return ret;
+
+	ret = batadv_tt_global_init(bat_priv);
+	if (ret < 0)
+		return ret;
+
+	batadv_tvlv_handler_register(bat_priv, batadv_tt_tvlv_ogm_handler_v1,
+				     NULL, BATADV_TVLV_TT, 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;
+}