batman-adv: tvlv - gateway download/upload bandwidth container

Prior to this patch batman-adv read the advertised uplink bandwidth
from userspace and compressed this information into a single byte
called "gateway class".
Now the download & upload bandwidth information is sent as-is. No
userspace change is necessary since the sysfs API always allowed
to specify a bandwidth.

Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
Signed-off-by: Spyros Gasteratos <morfeas3000@gmail.com>
Signed-off-by: Antonio Quartulli <antonio@meshcoding.com>

1 files changed, 121 insertions, 66 deletions

diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index 1ce4b8763ef2..1bce63aa5f5f 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -118,7 +118,6 @@ batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
         uint32_t max_gw_factor = 0, tmp_gw_factor = 0;
         uint32_t gw_divisor;
         uint8_t max_tq = 0;
-        int down, up;
         uint8_t tq_avg;
         struct batadv_orig_node *orig_node;
 
@@ -142,10 +141,9 @@ batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
 
                 switch (atomic_read(&bat_priv->gw_sel_class)) {
                 case 1: /* fast connection */
-                        batadv_gw_bandwidth_to_kbit(orig_node->gw_flags,
-                                                    &down, &up);
-
-                        tmp_gw_factor = tq_avg * tq_avg * down * 100 * 100;
+                        tmp_gw_factor = tq_avg * tq_avg;
+                        tmp_gw_factor *= gw_node->bandwidth_down;
+                        tmp_gw_factor *= 100 * 100;
                         tmp_gw_factor /= gw_divisor;
 
                         if ((tmp_gw_factor > max_gw_factor) ||
@@ -258,16 +256,22 @@ void batadv_gw_election(struct batadv_priv *bat_priv)
                                     NULL);
         } else if ((!curr_gw) && (next_gw)) {
                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-                           "Adding route to gateway %pM (gw_flags: %i, tq: %i)\n",
+                           "Adding route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
                            next_gw->orig_node->orig,
-                           next_gw->orig_node->gw_flags, router->tq_avg);
+                           next_gw->bandwidth_down / 10,
+                           next_gw->bandwidth_down % 10,
+                           next_gw->bandwidth_up / 10,
+                           next_gw->bandwidth_up % 10, router->tq_avg);
                 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_ADD,
                                     gw_addr);
         } else {
                 batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-                           "Changing route to gateway %pM (gw_flags: %i, tq: %i)\n",
+                           "Changing route to gateway %pM (bandwidth: %u.%u/%u.%u MBit, tq: %i)\n",
                            next_gw->orig_node->orig,
-                           next_gw->orig_node->gw_flags, router->tq_avg);
+                           next_gw->bandwidth_down / 10,
+                           next_gw->bandwidth_down % 10,
+                           next_gw->bandwidth_up / 10,
+                           next_gw->bandwidth_up % 10, router->tq_avg);
                 batadv_throw_uevent(bat_priv, BATADV_UEV_GW, BATADV_UEV_CHANGE,
                                     gw_addr);
         }
@@ -337,12 +341,20 @@ out:
         return;
 }
 
+/**
+ * batadv_gw_node_add - add gateway node to list of available gateways
+ * @bat_priv: the bat priv with all the soft interface information
+ * @orig_node: originator announcing gateway capabilities
+ * @gateway: announced bandwidth information
+ */
 static void batadv_gw_node_add(struct batadv_priv *bat_priv,
                                struct batadv_orig_node *orig_node,
-                               uint8_t new_gwflags)
+                               struct batadv_tvlv_gateway_data *gateway)
 {
         struct batadv_gw_node *gw_node;
-        int down, up;
+
+        if (gateway->bandwidth_down == 0)
+                return;
 
         gw_node = kzalloc(sizeof(*gw_node), GFP_ATOMIC);
         if (!gw_node)
@@ -356,73 +368,116 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv,
         hlist_add_head_rcu(&gw_node->list, &bat_priv->gw.list);
         spin_unlock_bh(&bat_priv->gw.list_lock);
 
-        batadv_gw_bandwidth_to_kbit(new_gwflags, &down, &up);
         batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-                   "Found new gateway %pM -> gw_class: %i - %i%s/%i%s\n",
-                   orig_node->orig, new_gwflags,
-                   (down > 2048 ? down / 1024 : down),
-                   (down > 2048 ? "MBit" : "KBit"),
-                   (up > 2048 ? up / 1024 : up),
-                   (up > 2048 ? "MBit" : "KBit"));
+                   "Found new gateway %pM -> gw bandwidth: %u.%u/%u.%u MBit\n",
+                   orig_node->orig,
+                   ntohl(gateway->bandwidth_down) / 10,
+                   ntohl(gateway->bandwidth_down) % 10,
+                   ntohl(gateway->bandwidth_up) / 10,
+                   ntohl(gateway->bandwidth_up) % 10);
 }
 
-void batadv_gw_node_update(struct batadv_priv *bat_priv,
-                           struct batadv_orig_node *orig_node,
-                           uint8_t new_gwflags)
+/**
+ * batadv_gw_node_get - retrieve gateway node from list of available gateways
+ * @bat_priv: the bat priv with all the soft interface information
+ * @orig_node: originator announcing gateway capabilities
+ *
+ * Returns gateway node if found or NULL otherwise.
+ */
+static struct batadv_gw_node *
+batadv_gw_node_get(struct batadv_priv *bat_priv,
+                   struct batadv_orig_node *orig_node)
 {
-        struct batadv_gw_node *gw_node, *curr_gw;
-
-        /* Note: We don't need a NULL check here, since curr_gw never gets
-         * dereferenced. If curr_gw is NULL we also should not exit as we may
-         * have this gateway in our list (duplication check!) even though we
-         * have no currently selected gateway.
-         */
-        curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
+        struct batadv_gw_node *gw_node_tmp, *gw_node = NULL;
 
         rcu_read_lock();
-        hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
-                if (gw_node->orig_node != orig_node)
+        hlist_for_each_entry_rcu(gw_node_tmp, &bat_priv->gw.list, list) {
+                if (gw_node_tmp->orig_node != orig_node)
                         continue;
 
-                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-                           "Gateway class of originator %pM changed from %i to %i\n",
-                           orig_node->orig, gw_node->orig_node->gw_flags,
-                           new_gwflags);
+                if (gw_node_tmp->deleted)
+                        continue;
 
-                gw_node->deleted = 0;
+                if (!atomic_inc_not_zero(&gw_node_tmp->refcount))
+                        continue;
 
-                if (new_gwflags == BATADV_NO_FLAGS) {
-                        gw_node->deleted = jiffies;
-                        batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-                                   "Gateway %pM removed from gateway list\n",
-                                   orig_node->orig);
+                gw_node = gw_node_tmp;
+                break;
+        }
+        rcu_read_unlock();
 
-                        if (gw_node == curr_gw)
-                                goto deselect;
-                }
+        return gw_node;
+}
 
-                goto unlock;
+/**
+ * batadv_gw_node_update - update list of available gateways with changed
+ *  bandwidth information
+ * @bat_priv: the bat priv with all the soft interface information
+ * @orig_node: originator announcing gateway capabilities
+ * @gateway: announced bandwidth information
+ */
+void batadv_gw_node_update(struct batadv_priv *bat_priv,
+                           struct batadv_orig_node *orig_node,
+                           struct batadv_tvlv_gateway_data *gateway)
+{
+        struct batadv_gw_node *gw_node, *curr_gw = NULL;
+
+        gw_node = batadv_gw_node_get(bat_priv, orig_node);
+        if (!gw_node) {
+                batadv_gw_node_add(bat_priv, orig_node, gateway);
+                goto out;
         }
 
-        if (new_gwflags == BATADV_NO_FLAGS)
-                goto unlock;
+        if ((gw_node->bandwidth_down == ntohl(gateway->bandwidth_down)) &&
+            (gw_node->bandwidth_up == ntohl(gateway->bandwidth_up)))
+                goto out;
 
-        batadv_gw_node_add(bat_priv, orig_node, new_gwflags);
-        goto unlock;
+        batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+                   "Gateway bandwidth of originator %pM changed from %u.%u/%u.%u MBit to %u.%u/%u.%u MBit\n",
+                   orig_node->orig,
+                   gw_node->bandwidth_down / 10,
+                   gw_node->bandwidth_down % 10,
+                   gw_node->bandwidth_up / 10,
+                   gw_node->bandwidth_up % 10,
+                   ntohl(gateway->bandwidth_down) / 10,
+                   ntohl(gateway->bandwidth_down) % 10,
+                   ntohl(gateway->bandwidth_up) / 10,
+                   ntohl(gateway->bandwidth_up) % 10);
+
+        gw_node->bandwidth_down = ntohl(gateway->bandwidth_down);
+        gw_node->bandwidth_up = ntohl(gateway->bandwidth_up);
+
+        gw_node->deleted = 0;
+        if (ntohl(gateway->bandwidth_down) == 0) {
+                gw_node->deleted = jiffies;
+                batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+                           "Gateway %pM removed from gateway list\n",
+                           orig_node->orig);
 
-deselect:
-        batadv_gw_deselect(bat_priv);
-unlock:
-        rcu_read_unlock();
+                /* Note: We don't need a NULL check here, since curr_gw never
+                 * gets dereferenced.
+                 */
+                curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
+                if (gw_node == curr_gw)
+                        batadv_gw_deselect(bat_priv);
+        }
 
+out:
         if (curr_gw)
                 batadv_gw_node_free_ref(curr_gw);
+        if (gw_node)
+                batadv_gw_node_free_ref(gw_node);
 }
 
 void batadv_gw_node_delete(struct batadv_priv *bat_priv,
                            struct batadv_orig_node *orig_node)
 {
-        batadv_gw_node_update(bat_priv, orig_node, 0);
+        struct batadv_tvlv_gateway_data gateway;
+
+        gateway.bandwidth_down = 0;
+        gateway.bandwidth_up = 0;
+
+        batadv_gw_node_update(bat_priv, orig_node, &gateway);
 }
 
 void batadv_gw_node_purge(struct batadv_priv *bat_priv)
@@ -467,9 +522,7 @@ static int batadv_write_buffer_text(struct batadv_priv *bat_priv,
 {
         struct batadv_gw_node *curr_gw;
         struct batadv_neigh_node *router;
-        int down, up, ret = -1;
-
-        batadv_gw_bandwidth_to_kbit(gw_node->orig_node->gw_flags, &down, &up);
+        int ret = -1;
 
         router = batadv_orig_node_get_router(gw_node->orig_node);
         if (!router)
@@ -477,16 +530,15 @@ static int batadv_write_buffer_text(struct batadv_priv *bat_priv,
 
         curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
 
-        ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %3i - %i%s/%i%s\n",
+        ret = seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %u.%u/%u.%u MBit\n",
                          (curr_gw == gw_node ? "=>" : "  "),
                          gw_node->orig_node->orig,
                          router->tq_avg, router->addr,
                          router->if_incoming->net_dev->name,
-                         gw_node->orig_node->gw_flags,
-                         (down > 2048 ? down / 1024 : down),
-                         (down > 2048 ? "MBit" : "KBit"),
-                         (up > 2048 ? up / 1024 : up),
-                         (up > 2048 ? "MBit" : "KBit"));
+                         gw_node->bandwidth_down / 10,
+                         gw_node->bandwidth_down % 10,
+                         gw_node->bandwidth_up / 10,
+                         gw_node->bandwidth_up % 10);
 
         batadv_neigh_node_free_ref(router);
         if (curr_gw)
@@ -508,7 +560,7 @@ int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
                 goto out;
 
         seq_printf(seq,
-                   "      %-12s (%s/%i) %17s [%10s]: gw_class ... [B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
+                   "      %-12s (%s/%i) %17s [%10s]: advertised uplink bandwidth ... [B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
                    "Gateway", "#", BATADV_TQ_MAX_VALUE, "Nexthop", "outgoingIF",
                    BATADV_SOURCE_VERSION, primary_if->net_dev->name,
                    primary_if->net_dev->dev_addr, net_dev->name);
@@ -675,7 +727,7 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
 {
         struct batadv_neigh_node *neigh_curr = NULL, *neigh_old = NULL;
         struct batadv_orig_node *orig_dst_node = NULL;
-        struct batadv_gw_node *curr_gw = NULL;
+        struct batadv_gw_node *gw_node = NULL, *curr_gw = NULL;
         struct ethhdr *ethhdr;
         bool ret, out_of_range = false;
         unsigned int header_len = 0;
@@ -691,7 +743,8 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv,
         if (!orig_dst_node)
                 goto out;
 
-        if (!orig_dst_node->gw_flags)
+        gw_node = batadv_gw_node_get(bat_priv, orig_dst_node);
+        if (!gw_node->bandwidth_down == 0)
                 goto out;
 
         ret = batadv_is_type_dhcprequest(skb, header_len);
@@ -742,6 +795,8 @@ out:
                 batadv_orig_node_free_ref(orig_dst_node);
         if (curr_gw)
                 batadv_gw_node_free_ref(curr_gw);
+        if (gw_node)
+                batadv_gw_node_free_ref(gw_node);
         if (neigh_old)
                 batadv_neigh_node_free_ref(neigh_old);
         if (neigh_curr)