Merge tag 'batadv-net-for-davem-20170316' of git://git.open-mesh.org/linux-merge

Simon Wunderlich says:

====================
Here are two batman-adv bugfixes:

 - Keep fragments equally sized, avoids some problems with too small fragments,
   by Sven Eckelmann

 - Initialize gateway class correctly when BATMAN V is compiled in,
   by Sven Eckelmann
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

6 files changed, 42 insertions, 11 deletions

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 7c3d994e90d8..71343d0fec94 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -2477,6 +2477,16 @@ static void batadv_iv_iface_activate(struct batadv_hard_iface *hard_iface)
         batadv_iv_ogm_schedule(hard_iface);
 }
 
+/**
+ * batadv_iv_init_sel_class - initialize GW selection class
+ * @bat_priv: the bat priv with all the soft interface information
+ */
+static void batadv_iv_init_sel_class(struct batadv_priv *bat_priv)
+{
+        /* set default TQ difference threshold to 20 */
+        atomic_set(&bat_priv->gw.sel_class, 20);
+}
+
 static struct batadv_gw_node *
 batadv_iv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
 {
@@ -2823,6 +2833,7 @@ static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
                 .del_if = batadv_iv_ogm_orig_del_if,
         },
         .gw = {
+                .init_sel_class = batadv_iv_init_sel_class,
                 .get_best_gw_node = batadv_iv_gw_get_best_gw_node,
                 .is_eligible = batadv_iv_gw_is_eligible,
 #ifdef CONFIG_BATMAN_ADV_DEBUGFS
diff --git a/net/batman-adv/bat_v.c b/net/batman-adv/bat_v.c
index 0acd081dd286..a36c8e7291d6 100644
--- a/net/batman-adv/bat_v.c
+++ b/net/batman-adv/bat_v.c
@@ -668,6 +668,16 @@ err_ifinfo1:
         return ret;
 }
 
+/**
+ * batadv_v_init_sel_class - initialize GW selection class
+ * @bat_priv: the bat priv with all the soft interface information
+ */
+static void batadv_v_init_sel_class(struct batadv_priv *bat_priv)
+{
+        /* set default throughput difference threshold to 5Mbps */
+        atomic_set(&bat_priv->gw.sel_class, 50);
+}
+
 static ssize_t batadv_v_store_sel_class(struct batadv_priv *bat_priv,
                                         char *buff, size_t count)
 {
@@ -1052,6 +1062,7 @@ static struct batadv_algo_ops batadv_batman_v __read_mostly = {
                 .dump = batadv_v_orig_dump,
         },
         .gw = {
+                .init_sel_class = batadv_v_init_sel_class,
                 .store_sel_class = batadv_v_store_sel_class,
                 .show_sel_class = batadv_v_show_sel_class,
                 .get_best_gw_node = batadv_v_gw_get_best_gw_node,
@@ -1092,9 +1103,6 @@ int batadv_v_mesh_init(struct batadv_priv *bat_priv)
         if (ret < 0)
                 return ret;
 
-        /* set default throughput difference threshold to 5Mbps */
-        atomic_set(&bat_priv->gw.sel_class, 50);
-
         return 0;
 }
 
diff --git a/net/batman-adv/fragmentation.c b/net/batman-adv/fragmentation.c
index 11a23fd6e1a0..8f964beaac28 100644
--- a/net/batman-adv/fragmentation.c
+++ b/net/batman-adv/fragmentation.c
@@ -404,7 +404,7 @@ out:
  * batadv_frag_create - create a fragment from skb
  * @skb: skb to create fragment from
  * @frag_head: header to use in new fragment
- * @mtu: size of new fragment
+ * @fragment_size: size of new fragment
  *
  * Split the passed skb into two fragments: A new one with size matching the
  * passed mtu and the old one with the rest. The new skb contains data from the
@@ -414,11 +414,11 @@ out:
  */
 static struct sk_buff *batadv_frag_create(struct sk_buff *skb,
                                           struct batadv_frag_packet *frag_head,
-                                          unsigned int mtu)
+                                          unsigned int fragment_size)
 {
         struct sk_buff *skb_fragment;
         unsigned int header_size = sizeof(*frag_head);
-        unsigned int fragment_size = mtu - header_size;
+        unsigned int mtu = fragment_size + header_size;
 
         skb_fragment = netdev_alloc_skb(NULL, mtu + ETH_HLEN);
         if (!skb_fragment)
@@ -456,7 +456,7 @@ int batadv_frag_send_packet(struct sk_buff *skb,
         struct sk_buff *skb_fragment;
         unsigned int mtu = neigh_node->if_incoming->net_dev->mtu;
         unsigned int header_size = sizeof(frag_header);
-        unsigned int max_fragment_size, max_packet_size;
+        unsigned int max_fragment_size, num_fragments;
         int ret;
 
         /* To avoid merge and refragmentation at next-hops we never send
@@ -464,10 +464,15 @@ int batadv_frag_send_packet(struct sk_buff *skb,
          */
         mtu = min_t(unsigned int, mtu, BATADV_FRAG_MAX_FRAG_SIZE);
         max_fragment_size = mtu - header_size;
-        max_packet_size = max_fragment_size * BATADV_FRAG_MAX_FRAGMENTS;
+
+        if (skb->len == 0 || max_fragment_size == 0)
+                return -EINVAL;
+
+        num_fragments = (skb->len - 1) / max_fragment_size + 1;
+        max_fragment_size = (skb->len - 1) / num_fragments + 1;
 
         /* Don't even try to fragment, if we need more than 16 fragments */
-        if (skb->len > max_packet_size) {
+        if (num_fragments > BATADV_FRAG_MAX_FRAGMENTS) {
                 ret = -EAGAIN;
                 goto free_skb;
         }
@@ -507,7 +512,8 @@ int batadv_frag_send_packet(struct sk_buff *skb,
                         goto put_primary_if;
                 }
 
-                skb_fragment = batadv_frag_create(skb, &frag_header, mtu);
+                skb_fragment = batadv_frag_create(skb, &frag_header,
+                                                  max_fragment_size);
                 if (!skb_fragment) {
                         ret = -ENOMEM;
                         goto put_primary_if;
diff --git a/net/batman-adv/gateway_common.c b/net/batman-adv/gateway_common.c
index 5db2e43e3775..33940c5c74a8 100644
--- a/net/batman-adv/gateway_common.c
+++ b/net/batman-adv/gateway_common.c
@@ -253,6 +253,11 @@ static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
  */
 void batadv_gw_init(struct batadv_priv *bat_priv)
 {
+        if (bat_priv->algo_ops->gw.init_sel_class)
+                bat_priv->algo_ops->gw.init_sel_class(bat_priv);
+        else
+                atomic_set(&bat_priv->gw.sel_class, 1);
+
         batadv_tvlv_handler_register(bat_priv, batadv_gw_tvlv_ogm_handler_v1,
                                      NULL, BATADV_TVLV_GW, 1,
                                      BATADV_TVLV_HANDLER_OGM_CIFNOTFND);
diff --git a/net/batman-adv/soft-interface.c b/net/batman-adv/soft-interface.c
index 5d099b2e6cfc..d042c99af028 100644
--- a/net/batman-adv/soft-interface.c
+++ b/net/batman-adv/soft-interface.c
@@ -819,7 +819,6 @@ static int batadv_softif_init_late(struct net_device *dev)
         atomic_set(&bat_priv->mcast.num_want_all_ipv6, 0);
 #endif
         atomic_set(&bat_priv->gw.mode, BATADV_GW_MODE_OFF);
-        atomic_set(&bat_priv->gw.sel_class, 20);
         atomic_set(&bat_priv->gw.bandwidth_down, 100);
         atomic_set(&bat_priv->gw.bandwidth_up, 20);
         atomic_set(&bat_priv->orig_interval, 1000);
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 66b25e410a41..246f21b4973b 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -1489,6 +1489,7 @@ struct batadv_algo_orig_ops {
 
 /**
  * struct batadv_algo_gw_ops - mesh algorithm callbacks (GW specific)
+ * @init_sel_class: initialize GW selection class (optional)
  * @store_sel_class: parse and stores a new GW selection class (optional)
  * @show_sel_class: prints the current GW selection class (optional)
  * @get_best_gw_node: select the best GW from the list of available nodes
@@ -1499,6 +1500,7 @@ struct batadv_algo_orig_ops {
  * @dump: dump gateways to a netlink socket (optional)
  */
 struct batadv_algo_gw_ops {
+        void (*init_sel_class)(struct batadv_priv *bat_priv);
         ssize_t (*store_sel_class)(struct batadv_priv *bat_priv, char *buff,
                                    size_t count);
         ssize_t (*show_sel_class)(struct batadv_priv *bat_priv, char *buff);