[B.A.T.M.A.N.] [PATCH v4 0/6] GW code: make it algorithm-agnostic and add B.A.T.M.A.N. V support

[B.A.T.M.A.N.] [PATCH v4 0/6] GW code: make it algorithm-agnostic and add B.A.T.M.A.N. V support

[Antonio Quartulli]

This cover letter only tries to recap the changes applied from the previous
version. Please check the patch for major details.

Changes from v1:
- rebased on top of latest master (some patches from the previous patchset were
  merged already)
- accidental change to the GW table header moved to right patch
- remove bat_ prefix from API names
- API subobjects redefined as proper struct instead of anonymous ones to fix
  kernel-doc complaints
- bonus kernel-doc added
- missing include files added

Changes from v2:
- minimum default value of gw_sel_class restored to 1

Changes from v3:
- move "batman-adv: split routing API data structure in subobjects" as patch 1
- check if algo_ops->gw.get_best_gw_node was implemented before calling it
- add patch to disable GW mode knobs if API have not been implemented (6/6)


Cheers,

Antonio Quartulli (6):
  batman-adv: split routing API data structure in subobjects
  batman-adv: make the GW selection class algorithm specific
  batman-adv: statically print gateway table header
  batman-adv: make GW election code protocol specific
  batman-adv: B.A.T.M.A.N. V - implement GW selection logic
  batman-adv: disable sysfs knobs when GW-mode is not implemented

 net/batman-adv/bat_algo.c          |  14 +-
 net/batman-adv/bat_iv_ogm.c        | 252 +++++++++++++++++++++++++++++++--
 net/batman-adv/bat_v.c             | 280 +++++++++++++++++++++++++++++++++++--
 net/batman-adv/bat_v_elp.c         |   2 +-
 net/batman-adv/bat_v_ogm.c         |   2 +-
 net/batman-adv/gateway_client.c    | 223 ++++-------------------------
 net/batman-adv/gateway_client.h    |   7 +
 net/batman-adv/gateway_common.c    |   5 +-
 net/batman-adv/hard-interface.c    |  16 +--
 net/batman-adv/netlink.c           |   2 +-
 net/batman-adv/originator.c        |  49 +++----
 net/batman-adv/routing.c           |   8 +-
 net/batman-adv/sysfs.c             |  64 ++++++++-
 net/batman-adv/translation-table.c |   6 +-
 net/batman-adv/types.h             | 137 +++++++++++-------
 15 files changed, 744 insertions(+), 323 deletions(-)

-- 
2.8.3

[B.A.T.M.A.N.] [PATCH v4 1/6] batman-adv: split routing API data structure in subobjects

[Antonio Quartulli]

The routing API data structure contains several function
pointers that can easily be grouped together based on the
component they work with.

Split the API in subobjects in order to improve definition readability.

At the same time, remove the "bat_" prefix from the API object and
its fields names. These are batman-adv private structs and there is no
need to always prepend such prefix, which only makes function invocations
much much longer.

Signed-off-by: Antonio Quartulli <a@unstable.cc>
---
 net/batman-adv/bat_algo.c          |  14 ++---
 net/batman-adv/bat_iv_ogm.c        |  33 ++++++-----
 net/batman-adv/bat_v.c             |  26 +++++----
 net/batman-adv/bat_v_elp.c         |   2 +-
 net/batman-adv/bat_v_ogm.c         |   2 +-
 net/batman-adv/hard-interface.c    |  16 +++---
 net/batman-adv/netlink.c           |   2 +-
 net/batman-adv/originator.c        |  49 ++++++++--------
 net/batman-adv/routing.c           |   8 +--
 net/batman-adv/sysfs.c             |   2 +-
 net/batman-adv/translation-table.c |   6 +-
 net/batman-adv/types.h             | 114 +++++++++++++++++++++----------------
 12 files changed, 150 insertions(+), 124 deletions(-)

diff --git a/net/batman-adv/bat_algo.c b/net/batman-adv/bat_algo.c
index 610d4de..81dbbf5 100644
--- a/net/batman-adv/bat_algo.c
+++ b/net/batman-adv/bat_algo.c
@@ -65,12 +65,12 @@ int batadv_algo_register(struct batadv_algo_ops *bat_algo_ops)
 	}
 
 	/* all algorithms must implement all ops (for now) */
-	if (!bat_algo_ops->bat_iface_enable ||
-	    !bat_algo_ops->bat_iface_disable ||
-	    !bat_algo_ops->bat_iface_update_mac ||
-	    !bat_algo_ops->bat_primary_iface_set ||
-	    !bat_algo_ops->bat_neigh_cmp ||
-	    !bat_algo_ops->bat_neigh_is_similar_or_better) {
+	if (!bat_algo_ops->iface.enable ||
+	    !bat_algo_ops->iface.disable ||
+	    !bat_algo_ops->iface.update_mac ||
+	    !bat_algo_ops->iface.primary_set ||
+	    !bat_algo_ops->neigh.cmp ||
+	    !bat_algo_ops->neigh.is_similar_or_better) {
 		pr_info("Routing algo '%s' does not implement required ops\n",
 			bat_algo_ops->name);
 		return -EINVAL;
@@ -90,7 +90,7 @@ int batadv_algo_select(struct batadv_priv *bat_priv, char *name)
 	if (!bat_algo_ops)
 		return -EINVAL;
 
-	bat_priv->bat_algo_ops = bat_algo_ops;
+	bat_priv->algo_ops = bat_algo_ops;
 
 	return 0;
 }
diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index e2d8848..19b0abd 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -1853,8 +1853,7 @@ static int batadv_iv_ogm_receive(struct sk_buff *skb,
 	/* did we receive a B.A.T.M.A.N. IV OGM packet on an interface
 	 * that does not have B.A.T.M.A.N. IV enabled ?
 	 */
-	if (bat_priv->bat_algo_ops->bat_iface_enable !=
-	    batadv_iv_ogm_iface_enable)
+	if (bat_priv->algo_ops->iface.enable != batadv_iv_ogm_iface_enable)
 		return NET_RX_DROP;
 
 	batadv_inc_counter(bat_priv, BATADV_CNT_MGMT_RX);
@@ -2120,18 +2119,24 @@ static void batadv_iv_iface_activate(struct batadv_hard_iface *hard_iface)
 
 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
 	.name = "BATMAN_IV",
-	.bat_iface_activate = batadv_iv_iface_activate,
-	.bat_iface_enable = batadv_iv_ogm_iface_enable,
-	.bat_iface_disable = batadv_iv_ogm_iface_disable,
-	.bat_iface_update_mac = batadv_iv_ogm_iface_update_mac,
-	.bat_primary_iface_set = batadv_iv_ogm_primary_iface_set,
-	.bat_neigh_cmp = batadv_iv_ogm_neigh_cmp,
-	.bat_neigh_is_similar_or_better = batadv_iv_ogm_neigh_is_sob,
-	.bat_neigh_print = batadv_iv_neigh_print,
-	.bat_orig_print = batadv_iv_ogm_orig_print,
-	.bat_orig_free = batadv_iv_ogm_orig_free,
-	.bat_orig_add_if = batadv_iv_ogm_orig_add_if,
-	.bat_orig_del_if = batadv_iv_ogm_orig_del_if,
+	.iface = {
+		.activate = batadv_iv_iface_activate,
+		.enable = batadv_iv_ogm_iface_enable,
+		.disable = batadv_iv_ogm_iface_disable,
+		.update_mac = batadv_iv_ogm_iface_update_mac,
+		.primary_set = batadv_iv_ogm_primary_iface_set,
+	},
+	.neigh = {
+		.cmp = batadv_iv_ogm_neigh_cmp,
+		.is_similar_or_better = batadv_iv_ogm_neigh_is_sob,
+		.print = batadv_iv_neigh_print,
+	},
+	.orig = {
+		.print = batadv_iv_ogm_orig_print,
+		.free = batadv_iv_ogm_orig_free,
+		.add_if = batadv_iv_ogm_orig_add_if,
+		.del_if = batadv_iv_ogm_orig_del_if,
+	},
 };
 
 int __init batadv_iv_init(void)
diff --git a/net/batman-adv/bat_v.c b/net/batman-adv/bat_v.c
index e4a91cd..b9e1db0 100644
--- a/net/batman-adv/bat_v.c
+++ b/net/batman-adv/bat_v.c
@@ -321,16 +321,22 @@ err_ifinfo1:
 
 static struct batadv_algo_ops batadv_batman_v __read_mostly = {
 	.name = "BATMAN_V",
-	.bat_iface_activate = batadv_v_iface_activate,
-	.bat_iface_enable = batadv_v_iface_enable,
-	.bat_iface_disable = batadv_v_iface_disable,
-	.bat_iface_update_mac = batadv_v_iface_update_mac,
-	.bat_primary_iface_set = batadv_v_primary_iface_set,
-	.bat_hardif_neigh_init = batadv_v_hardif_neigh_init,
-	.bat_orig_print = batadv_v_orig_print,
-	.bat_neigh_cmp = batadv_v_neigh_cmp,
-	.bat_neigh_is_similar_or_better = batadv_v_neigh_is_sob,
-	.bat_neigh_print = batadv_v_neigh_print,
+	.iface = {
+		.activate = batadv_v_iface_activate,
+		.enable = batadv_v_iface_enable,
+		.disable = batadv_v_iface_disable,
+		.update_mac = batadv_v_iface_update_mac,
+		.primary_set = batadv_v_primary_iface_set,
+	},
+	.neigh = {
+		.hardif_init = batadv_v_hardif_neigh_init,
+		.cmp = batadv_v_neigh_cmp,
+		.is_similar_or_better = batadv_v_neigh_is_sob,
+		.print = batadv_v_neigh_print,
+	},
+	.orig = {
+		.print = batadv_v_orig_print,
+	},
 };
 
 /**
diff --git a/net/batman-adv/bat_v_elp.c b/net/batman-adv/bat_v_elp.c
index 15cf272..7d17001 100644
--- a/net/batman-adv/bat_v_elp.c
+++ b/net/batman-adv/bat_v_elp.c
@@ -504,7 +504,7 @@ int batadv_v_elp_packet_recv(struct sk_buff *skb,
 	/* did we receive a B.A.T.M.A.N. V ELP packet on an interface
 	 * that does not have B.A.T.M.A.N. V ELP enabled ?
 	 */
-	if (strcmp(bat_priv->bat_algo_ops->name, "BATMAN_V") != 0)
+	if (strcmp(bat_priv->algo_ops->name, "BATMAN_V") != 0)
 		return NET_RX_DROP;
 
 	elp_packet = (struct batadv_elp_packet *)skb->data;
diff --git a/net/batman-adv/bat_v_ogm.c b/net/batman-adv/bat_v_ogm.c
index 7ac9e0b..6fbba4e 100644
--- a/net/batman-adv/bat_v_ogm.c
+++ b/net/batman-adv/bat_v_ogm.c
@@ -754,7 +754,7 @@ int batadv_v_ogm_packet_recv(struct sk_buff *skb,
 	/* did we receive a OGM2 packet on an interface that does not have
 	 * B.A.T.M.A.N. V enabled ?
 	 */
-	if (strcmp(bat_priv->bat_algo_ops->name, "BATMAN_V") != 0)
+	if (strcmp(bat_priv->algo_ops->name, "BATMAN_V") != 0)
 		return NET_RX_DROP;
 
 	if (!batadv_check_management_packet(skb, if_incoming, BATADV_OGM2_HLEN))
diff --git a/net/batman-adv/hard-interface.c b/net/batman-adv/hard-interface.c
index 6689656..0229860 100644
--- a/net/batman-adv/hard-interface.c
+++ b/net/batman-adv/hard-interface.c
@@ -246,7 +246,7 @@ static void batadv_primary_if_select(struct batadv_priv *bat_priv,
 	if (!new_hard_iface)
 		goto out;
 
-	bat_priv->bat_algo_ops->bat_primary_iface_set(new_hard_iface);
+	bat_priv->algo_ops->iface.primary_set(new_hard_iface);
 	batadv_primary_if_update_addr(bat_priv, curr_hard_iface);
 
 out:
@@ -393,7 +393,7 @@ batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
 
 	bat_priv = netdev_priv(hard_iface->soft_iface);
 
-	bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
+	bat_priv->algo_ops->iface.update_mac(hard_iface);
 	hard_iface->if_status = BATADV_IF_TO_BE_ACTIVATED;
 
 	/* the first active interface becomes our primary interface or
@@ -408,8 +408,8 @@ batadv_hardif_activate_interface(struct batadv_hard_iface *hard_iface)
 
 	batadv_update_min_mtu(hard_iface->soft_iface);
 
-	if (bat_priv->bat_algo_ops->bat_iface_activate)
-		bat_priv->bat_algo_ops->bat_iface_activate(hard_iface);
+	if (bat_priv->algo_ops->iface.activate)
+		bat_priv->algo_ops->iface.activate(hard_iface);
 
 out:
 	if (primary_if)
@@ -507,7 +507,7 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
 	if (ret)
 		goto err_dev;
 
-	ret = bat_priv->bat_algo_ops->bat_iface_enable(hard_iface);
+	ret = bat_priv->algo_ops->iface.enable(hard_iface);
 	if (ret < 0)
 		goto err_upper;
 
@@ -516,7 +516,7 @@ int batadv_hardif_enable_interface(struct batadv_hard_iface *hard_iface,
 	hard_iface->if_status = BATADV_IF_INACTIVE;
 	ret = batadv_orig_hash_add_if(hard_iface, bat_priv->num_ifaces);
 	if (ret < 0) {
-		bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
+		bat_priv->algo_ops->iface.disable(hard_iface);
 		bat_priv->num_ifaces--;
 		hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 		goto err_upper;
@@ -597,7 +597,7 @@ void batadv_hardif_disable_interface(struct batadv_hard_iface *hard_iface,
 			batadv_hardif_put(new_if);
 	}
 
-	bat_priv->bat_algo_ops->bat_iface_disable(hard_iface);
+	bat_priv->algo_ops->iface.disable(hard_iface);
 	hard_iface->if_status = BATADV_IF_NOT_IN_USE;
 
 	/* delete all references to this hard_iface */
@@ -789,7 +789,7 @@ static int batadv_hard_if_event(struct notifier_block *this,
 		batadv_check_known_mac_addr(hard_iface->net_dev);
 
 		bat_priv = netdev_priv(hard_iface->soft_iface);
-		bat_priv->bat_algo_ops->bat_iface_update_mac(hard_iface);
+		bat_priv->algo_ops->iface.update_mac(hard_iface);
 
 		primary_if = batadv_primary_if_get_selected(bat_priv);
 		if (!primary_if)
diff --git a/net/batman-adv/netlink.c b/net/batman-adv/netlink.c
index 56e63ce..3d1dcdd 100644
--- a/net/batman-adv/netlink.c
+++ b/net/batman-adv/netlink.c
@@ -89,7 +89,7 @@ batadv_netlink_mesh_info_put(struct sk_buff *msg, struct net_device *soft_iface)
 
 	if (nla_put_string(msg, BATADV_ATTR_VERSION, BATADV_SOURCE_VERSION) ||
 	    nla_put_string(msg, BATADV_ATTR_ALGO_NAME,
-			   bat_priv->bat_algo_ops->name) ||
+			   bat_priv->algo_ops->name) ||
 	    nla_put_u32(msg, BATADV_ATTR_MESH_IFINDEX, soft_iface->ifindex) ||
 	    nla_put_string(msg, BATADV_ATTR_MESH_IFNAME, soft_iface->name) ||
 	    nla_put(msg, BATADV_ATTR_MESH_ADDRESS, ETH_ALEN,
diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index 8ad17ad..7d1e542 100644
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -534,8 +534,8 @@ batadv_hardif_neigh_create(struct batadv_hard_iface *hard_iface,
 
 	kref_init(&hardif_neigh->refcount);
 
-	if (bat_priv->bat_algo_ops->bat_hardif_neigh_init)
-		bat_priv->bat_algo_ops->bat_hardif_neigh_init(hardif_neigh);
+	if (bat_priv->algo_ops->neigh.hardif_init)
+		bat_priv->algo_ops->neigh.hardif_init(hardif_neigh);
 
 	hlist_add_head(&hardif_neigh->list, &hard_iface->neigh_list);
 
@@ -706,17 +706,17 @@ int batadv_hardif_neigh_seq_print_text(struct seq_file *seq, void *offset)
 	seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s %s)]\n",
 		   BATADV_SOURCE_VERSION, primary_if->net_dev->name,
 		   primary_if->net_dev->dev_addr, net_dev->name,
-		   bat_priv->bat_algo_ops->name);
+		   bat_priv->algo_ops->name);
 
 	batadv_hardif_put(primary_if);
 
-	if (!bat_priv->bat_algo_ops->bat_neigh_print) {
+	if (!bat_priv->algo_ops->neigh.print) {
 		seq_puts(seq,
 			 "No printing function for this routing protocol\n");
 		return 0;
 	}
 
-	bat_priv->bat_algo_ops->bat_neigh_print(bat_priv, seq);
+	bat_priv->algo_ops->neigh.print(bat_priv, seq);
 	return 0;
 }
 
@@ -767,8 +767,8 @@ static void batadv_orig_node_free_rcu(struct rcu_head *rcu)
 
 	batadv_frag_purge_orig(orig_node, NULL);
 
-	if (orig_node->bat_priv->bat_algo_ops->bat_orig_free)
-		orig_node->bat_priv->bat_algo_ops->bat_orig_free(orig_node);
+	if (orig_node->bat_priv->algo_ops->orig.free)
+		orig_node->bat_priv->algo_ops->orig.free(orig_node);
 
 	kfree(orig_node->tt_buff);
 	kfree(orig_node);
@@ -1097,12 +1097,12 @@ batadv_find_best_neighbor(struct batadv_priv *bat_priv,
 			  struct batadv_hard_iface *if_outgoing)
 {
 	struct batadv_neigh_node *best = NULL, *neigh;
-	struct batadv_algo_ops *bao = bat_priv->bat_algo_ops;
+	struct batadv_algo_ops *bao = bat_priv->algo_ops;
 
 	rcu_read_lock();
 	hlist_for_each_entry_rcu(neigh, &orig_node->neigh_list, list) {
-		if (best && (bao->bat_neigh_cmp(neigh, if_outgoing,
-						best, if_outgoing) <= 0))
+		if (best && (bao->neigh.cmp(neigh, if_outgoing, best,
+					    if_outgoing) <= 0))
 			continue;
 
 		if (!kref_get_unless_zero(&neigh->refcount))
@@ -1254,18 +1254,17 @@ int batadv_orig_seq_print_text(struct seq_file *seq, void *offset)
 	seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s %s)]\n",
 		   BATADV_SOURCE_VERSION, primary_if->net_dev->name,
 		   primary_if->net_dev->dev_addr, net_dev->name,
-		   bat_priv->bat_algo_ops->name);
+		   bat_priv->algo_ops->name);
 
 	batadv_hardif_put(primary_if);
 
-	if (!bat_priv->bat_algo_ops->bat_orig_print) {
+	if (!bat_priv->algo_ops->orig.print) {
 		seq_puts(seq,
 			 "No printing function for this routing protocol\n");
 		return 0;
 	}
 
-	bat_priv->bat_algo_ops->bat_orig_print(bat_priv, seq,
-					       BATADV_IF_DEFAULT);
+	bat_priv->algo_ops->orig.print(bat_priv, seq, BATADV_IF_DEFAULT);
 
 	return 0;
 }
@@ -1292,7 +1291,7 @@ int batadv_orig_hardif_seq_print_text(struct seq_file *seq, void *offset)
 	}
 
 	bat_priv = netdev_priv(hard_iface->soft_iface);
-	if (!bat_priv->bat_algo_ops->bat_orig_print) {
+	if (!bat_priv->algo_ops->orig.print) {
 		seq_puts(seq,
 			 "No printing function for this routing protocol\n");
 		goto out;
@@ -1306,9 +1305,9 @@ int batadv_orig_hardif_seq_print_text(struct seq_file *seq, void *offset)
 	seq_printf(seq, "[B.A.T.M.A.N. adv %s, IF/MAC: %s/%pM (%s %s)]\n",
 		   BATADV_SOURCE_VERSION, hard_iface->net_dev->name,
 		   hard_iface->net_dev->dev_addr,
-		   hard_iface->soft_iface->name, bat_priv->bat_algo_ops->name);
+		   hard_iface->soft_iface->name, bat_priv->algo_ops->name);
 
-	bat_priv->bat_algo_ops->bat_orig_print(bat_priv, seq, hard_iface);
+	bat_priv->algo_ops->orig.print(bat_priv, seq, hard_iface);
 
 out:
 	if (hard_iface)
@@ -1320,7 +1319,7 @@ int batadv_orig_hash_add_if(struct batadv_hard_iface *hard_iface,
 			    int max_if_num)
 {
 	struct batadv_priv *bat_priv = netdev_priv(hard_iface->soft_iface);
-	struct batadv_algo_ops *bao = bat_priv->bat_algo_ops;
+	struct batadv_algo_ops *bao = bat_priv->algo_ops;
 	struct batadv_hashtable *hash = bat_priv->orig_hash;
 	struct hlist_head *head;
 	struct batadv_orig_node *orig_node;
@@ -1336,9 +1335,8 @@ int batadv_orig_hash_add_if(struct batadv_hard_iface *hard_iface,
 		rcu_read_lock();
 		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 			ret = 0;
-			if (bao->bat_orig_add_if)
-				ret = bao->bat_orig_add_if(orig_node,
-							   max_if_num);
+			if (bao->orig.add_if)
+				ret = bao->orig.add_if(orig_node, max_if_num);
 			if (ret == -ENOMEM)
 				goto err;
 		}
@@ -1360,7 +1358,7 @@ int batadv_orig_hash_del_if(struct batadv_hard_iface *hard_iface,
 	struct hlist_head *head;
 	struct batadv_hard_iface *hard_iface_tmp;
 	struct batadv_orig_node *orig_node;
-	struct batadv_algo_ops *bao = bat_priv->bat_algo_ops;
+	struct batadv_algo_ops *bao = bat_priv->algo_ops;
 	u32 i;
 	int ret;
 
@@ -1373,10 +1371,9 @@ int batadv_orig_hash_del_if(struct batadv_hard_iface *hard_iface,
 		rcu_read_lock();
 		hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
 			ret = 0;
-			if (bao->bat_orig_del_if)
-				ret = bao->bat_orig_del_if(orig_node,
-							   max_if_num,
-							   hard_iface->if_num);
+			if (bao->orig.del_if)
+				ret = bao->orig.del_if(orig_node, max_if_num,
+						       hard_iface->if_num);
 			if (ret == -ENOMEM)
 				goto err;
 		}
diff --git a/net/batman-adv/routing.c b/net/batman-adv/routing.c
index b9a500a..b729a8b 100644
--- a/net/batman-adv/routing.c
+++ b/net/batman-adv/routing.c
@@ -483,7 +483,7 @@ batadv_find_router(struct batadv_priv *bat_priv,
 		   struct batadv_orig_node *orig_node,
 		   struct batadv_hard_iface *recv_if)
 {
-	struct batadv_algo_ops *bao = bat_priv->bat_algo_ops;
+	struct batadv_algo_ops *bao = bat_priv->algo_ops;
 	struct batadv_neigh_node *first_candidate_router = NULL;
 	struct batadv_neigh_node *next_candidate_router = NULL;
 	struct batadv_neigh_node *router, *cand_router = NULL;
@@ -537,9 +537,9 @@ batadv_find_router(struct batadv_priv *bat_priv,
 		/* alternative candidate should be good enough to be
 		 * considered
 		 */
-		if (!bao->bat_neigh_is_similar_or_better(cand_router,
-							 cand->if_outgoing,
-							 router, recv_if))
+		if (!bao->neigh.is_similar_or_better(cand_router,
+						     cand->if_outgoing, router,
+						     recv_if))
 			goto next;
 
 		/* don't use the same router twice */
diff --git a/net/batman-adv/sysfs.c b/net/batman-adv/sysfs.c
index 1a7942d..fe9ca94 100644
--- a/net/batman-adv/sysfs.c
+++ b/net/batman-adv/sysfs.c
@@ -412,7 +412,7 @@ static ssize_t batadv_show_bat_algo(struct kobject *kobj,
 {
 	struct batadv_priv *bat_priv = batadv_kobj_to_batpriv(kobj);
 
-	return sprintf(buff, "%s\n", bat_priv->bat_algo_ops->name);
+	return sprintf(buff, "%s\n", bat_priv->algo_ops->name);
 }
 
 static void batadv_post_gw_reselect(struct net_device *net_dev)
diff --git a/net/batman-adv/translation-table.c b/net/batman-adv/translation-table.c
index 9be4ff0..2057cbe 100644
--- a/net/batman-adv/translation-table.c
+++ b/net/batman-adv/translation-table.c
@@ -1550,7 +1550,7 @@ batadv_transtable_best_orig(struct batadv_priv *bat_priv,
 			    struct batadv_tt_global_entry *tt_global_entry)
 {
 	struct batadv_neigh_node *router, *best_router = NULL;
-	struct batadv_algo_ops *bao = bat_priv->bat_algo_ops;
+	struct batadv_algo_ops *bao = bat_priv->algo_ops;
 	struct hlist_head *head;
 	struct batadv_tt_orig_list_entry *orig_entry, *best_entry = NULL;
 
@@ -1562,8 +1562,8 @@ batadv_transtable_best_orig(struct batadv_priv *bat_priv,
 			continue;
 
 		if (best_router &&
-		    bao->bat_neigh_cmp(router, BATADV_IF_DEFAULT,
-				       best_router, BATADV_IF_DEFAULT) <= 0) {
+		    bao->neigh.cmp(router, BATADV_IF_DEFAULT, best_router,
+				   BATADV_IF_DEFAULT) <= 0) {
 			batadv_neigh_node_put(router);
 			continue;
 		}
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index a331e3a..4d6a7ce 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -1016,7 +1016,7 @@ struct batadv_priv_bat_v {
  * @cleanup_work: work queue callback item for soft-interface deinit
  * @primary_if: one of the hard-interfaces assigned to this mesh interface
  *  becomes the primary interface
- * @bat_algo_ops: routing algorithm used by this mesh interface
+ * @algo_ops: routing algorithm used by this mesh interface
  * @softif_vlan_list: a list of softif_vlan structs, one per VLAN created on top
  *  of the mesh interface represented by this object
  * @softif_vlan_list_lock: lock protecting softif_vlan_list
@@ -1074,7 +1074,7 @@ struct batadv_priv {
 	struct delayed_work orig_work;
 	struct work_struct cleanup_work;
 	struct batadv_hard_iface __rcu *primary_if;  /* rcu protected pointer */
-	struct batadv_algo_ops *bat_algo_ops;
+	struct batadv_algo_ops *algo_ops;
 	struct hlist_head softif_vlan_list;
 	spinlock_t softif_vlan_list_lock; /* protects softif_vlan_list */
 #ifdef CONFIG_BATMAN_ADV_BLA
@@ -1388,59 +1388,77 @@ struct batadv_forw_packet {
 };
 
 /**
+ * struct batadv_algo_iface_ops - mesh algorithm callbacks (interface specific)
+ * @activate: start routing mechanisms when hard-interface is brought up
+ * @enable: init routing info when hard-interface is enabled
+ * @disable: de-init routing info when hard-interface is disabled
+ * @update_mac: (re-)init mac addresses of the protocol information
+ *  belonging to this hard-interface
+ * @primary_set: called when primary interface is selected / changed
+ */
+struct batadv_algo_iface_ops {
+	void (*activate)(struct batadv_hard_iface *hard_iface);
+	int (*enable)(struct batadv_hard_iface *hard_iface);
+	void (*disable)(struct batadv_hard_iface *hard_iface);
+	void (*update_mac)(struct batadv_hard_iface *hard_iface);
+	void (*primary_set)(struct batadv_hard_iface *hard_iface);
+};
+
+/**
+ * struct batadv_algo_neigh_ops - mesh algorithm callbacks (neighbour specific)
+ * @hardif_init: called on creation of single hop entry
+ * @cmp: compare the metrics of two neighbors for their respective outgoing
+ *  interfaces
+ * @is_similar_or_better: check if neigh1 is equally similar or better than
+ *  neigh2 for their respective outgoing interface from the metric prospective
+ * @print: print the single hop neighbor list (optional)
+ */
+struct batadv_algo_neigh_ops {
+	void (*hardif_init)(struct batadv_hardif_neigh_node *neigh);
+	int (*cmp)(struct batadv_neigh_node *neigh1,
+		   struct batadv_hard_iface *if_outgoing1,
+		   struct batadv_neigh_node *neigh2,
+		   struct batadv_hard_iface *if_outgoing2);
+	bool (*is_similar_or_better)(struct batadv_neigh_node *neigh1,
+				     struct batadv_hard_iface *if_outgoing1,
+				     struct batadv_neigh_node *neigh2,
+				     struct batadv_hard_iface *if_outgoing2);
+	void (*print)(struct batadv_priv *priv, struct seq_file *seq);
+};
+
+/**
+ * struct batadv_algo_orig_ops - mesh algorithm callbacks (originator specific)
+ * @free: free the resources allocated by the routing algorithm for an orig_node
+ *  object
+ * @add_if: ask the routing algorithm to apply the needed changes to the
+ *  orig_node due to a new hard-interface being added into the mesh
+ * @del_if: ask the routing algorithm to apply the needed changes to the
+ *  orig_node due to an hard-interface being removed from the mesh
+ * @print: print the originator table (optional)
+ */
+struct batadv_algo_orig_ops {
+	void (*free)(struct batadv_orig_node *orig_node);
+	int (*add_if)(struct batadv_orig_node *orig_node, int max_if_num);
+	int (*del_if)(struct batadv_orig_node *orig_node, int max_if_num,
+		      int del_if_num);
+	void (*print)(struct batadv_priv *priv, struct seq_file *seq,
+		      struct batadv_hard_iface *hard_iface);
+};
+
+/**
  * struct batadv_algo_ops - mesh algorithm callbacks
  * @list: list node for the batadv_algo_list
  * @name: name of the algorithm
- * @bat_iface_activate: start routing mechanisms when hard-interface is brought
- *  up
- * @bat_iface_enable: init routing info when hard-interface is enabled
- * @bat_iface_disable: de-init routing info when hard-interface is disabled
- * @bat_iface_update_mac: (re-)init mac addresses of the protocol information
- *  belonging to this hard-interface
- * @bat_primary_iface_set: called when primary interface is selected / changed
- * @bat_hardif_neigh_init: called on creation of single hop entry
- * @bat_neigh_cmp: compare the metrics of two neighbors for their respective
- *  outgoing interfaces
- * @bat_neigh_is_similar_or_better: check if neigh1 is equally similar or
- *  better than neigh2 for their respective outgoing interface from the metric
- *  prospective
- * @bat_neigh_print: print the single hop neighbor list (optional)
- * @bat_orig_print: print the originator table (optional)
- * @bat_orig_free: free the resources allocated by the routing algorithm for an
- *  orig_node object
- * @bat_orig_add_if: ask the routing algorithm to apply the needed changes to
- *  the orig_node due to a new hard-interface being added into the mesh
- * @bat_orig_del_if: ask the routing algorithm to apply the needed changes to
- *  the orig_node due to an hard-interface being removed from the mesh
+ * @iface: callbacks related to interface handling
+ * @neigh: callbacks related to neighbors handling
+ * @orig: callbacks related to originators handling
  */
 struct batadv_algo_ops {
 	struct hlist_node list;
 	char *name;
-	void (*bat_iface_activate)(struct batadv_hard_iface *hard_iface);
-	int (*bat_iface_enable)(struct batadv_hard_iface *hard_iface);
-	void (*bat_iface_disable)(struct batadv_hard_iface *hard_iface);
-	void (*bat_iface_update_mac)(struct batadv_hard_iface *hard_iface);
-	void (*bat_primary_iface_set)(struct batadv_hard_iface *hard_iface);
-	/* neigh_node handling API */
-	void (*bat_hardif_neigh_init)(struct batadv_hardif_neigh_node *neigh);
-	int (*bat_neigh_cmp)(struct batadv_neigh_node *neigh1,
-			     struct batadv_hard_iface *if_outgoing1,
-			     struct batadv_neigh_node *neigh2,
-			     struct batadv_hard_iface *if_outgoing2);
-	bool (*bat_neigh_is_similar_or_better)
-		(struct batadv_neigh_node *neigh1,
-		 struct batadv_hard_iface *if_outgoing1,
-		 struct batadv_neigh_node *neigh2,
-		 struct batadv_hard_iface *if_outgoing2);
-	void (*bat_neigh_print)(struct batadv_priv *priv, struct seq_file *seq);
-	/* orig_node handling API */
-	void (*bat_orig_print)(struct batadv_priv *priv, struct seq_file *seq,
-			       struct batadv_hard_iface *hard_iface);
-	void (*bat_orig_free)(struct batadv_orig_node *orig_node);
-	int (*bat_orig_add_if)(struct batadv_orig_node *orig_node,
-			       int max_if_num);
-	int (*bat_orig_del_if)(struct batadv_orig_node *orig_node,
-			       int max_if_num, int del_if_num);
+	struct batadv_algo_iface_ops iface;
+	struct batadv_algo_neigh_ops neigh;
+	struct batadv_algo_orig_ops orig;
 };
 
 /**
-- 
2.8.3

[B.A.T.M.A.N.] [PATCH v4 2/6] batman-adv: make the GW selection class algorithm specific

[Antonio Quartulli]

The B.A.T.M.A.N. V algorithm uses a different metric compared to its
predecessor and for this reason the logic used to compute the best
Gateway is also changed. This means that the GW selection class
fed to this logic has a semantics that depends on the algorithm being
used.

Make the parsing and printing routine of the GW selection class
routing algorithm specific. Each algorithm can now parse (and print)
this value independently.

If no API is provided by any algorithm, the default is to use the
current mechanism of considering such value like an integer between
1 and 255.

Signed-off-by: Antonio Quartulli <a@unstable.cc>
---
 net/batman-adv/bat_v.c | 34 ++++++++++++++++++++++++++++++++++
 net/batman-adv/sysfs.c | 34 ++++++++++++++++++++++++++++++++--
 net/batman-adv/types.h | 13 +++++++++++++
 3 files changed, 79 insertions(+), 2 deletions(-)

diff --git a/net/batman-adv/bat_v.c b/net/batman-adv/bat_v.c
index b9e1db0..3066e59 100644
--- a/net/batman-adv/bat_v.c
+++ b/net/batman-adv/bat_v.c
@@ -20,8 +20,10 @@
 
 #include <linux/bug.h>
 #include <linux/cache.h>
+#include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/jiffies.h>
+#include <linux/kernel.h>
 #include <linux/netdevice.h>
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
@@ -33,6 +35,8 @@
 #include "bat_algo.h"
 #include "bat_v_elp.h"
 #include "bat_v_ogm.h"
+#include "gateway_client.h"
+#include "gateway_common.h"
 #include "hard-interface.h"
 #include "hash.h"
 #include "originator.h"
@@ -319,6 +323,32 @@ err_ifinfo1:
 	return ret;
 }
 
+static ssize_t batadv_v_store_sel_class(struct batadv_priv *bat_priv,
+					char *buff, size_t count)
+{
+	u32 old_class, class;
+
+	if (!batadv_parse_throughput(bat_priv->soft_iface, buff,
+				     "B.A.T.M.A.N. V GW selection class",
+				     &class))
+		return -EINVAL;
+
+	old_class = atomic_read(&bat_priv->gw.sel_class);
+	atomic_set(&bat_priv->gw.sel_class, class);
+
+	if (old_class != class)
+		batadv_gw_reselect(bat_priv);
+
+	return count;
+}
+
+static ssize_t batadv_v_show_sel_class(struct batadv_priv *bat_priv, char *buff)
+{
+	u32 class = atomic_read(&bat_priv->gw.sel_class);
+
+	return sprintf(buff, "%u.%u MBit\n", class / 10, class % 10);
+}
+
 static struct batadv_algo_ops batadv_batman_v __read_mostly = {
 	.name = "BATMAN_V",
 	.iface = {
@@ -337,6 +367,10 @@ static struct batadv_algo_ops batadv_batman_v __read_mostly = {
 	.orig = {
 		.print = batadv_v_orig_print,
 	},
+	.gw = {
+		.store_sel_class = batadv_v_store_sel_class,
+		.show_sel_class = batadv_v_show_sel_class,
+	},
 };
 
 /**
diff --git a/net/batman-adv/sysfs.c b/net/batman-adv/sysfs.c
index fe9ca94..bb43742 100644
--- a/net/batman-adv/sysfs.c
+++ b/net/batman-adv/sysfs.c
@@ -514,6 +514,36 @@ static ssize_t batadv_store_gw_mode(struct kobject *kobj,
 	return count;
 }
 
+static ssize_t batadv_show_gw_sel_class(struct kobject *kobj,
+					struct attribute *attr, char *buff)
+{
+	struct batadv_priv *bat_priv = batadv_kobj_to_batpriv(kobj);
+
+	if (bat_priv->algo_ops->gw.show_sel_class)
+		return bat_priv->algo_ops->gw.show_sel_class(bat_priv, buff);
+
+	return sprintf(buff, "%i\n", atomic_read(&bat_priv->gw.sel_class));
+}
+
+static ssize_t batadv_store_gw_sel_class(struct kobject *kobj,
+					 struct attribute *attr, char *buff,
+					 size_t count)
+{
+	struct batadv_priv *bat_priv = batadv_kobj_to_batpriv(kobj);
+
+	if (buff[count - 1] == '\n')
+		buff[count - 1] = '\0';
+
+	if (bat_priv->algo_ops->gw.store_sel_class)
+		return bat_priv->algo_ops->gw.store_sel_class(bat_priv, buff,
+							      count);
+
+	return __batadv_store_uint_attr(buff, count, 1, BATADV_TQ_MAX_VALUE,
+					batadv_post_gw_reselect, attr,
+					&bat_priv->gw.sel_class,
+					bat_priv->soft_iface);
+}
+
 static ssize_t batadv_show_gw_bwidth(struct kobject *kobj,
 				     struct attribute *attr, char *buff)
 {
@@ -625,8 +655,8 @@ BATADV_ATTR_SIF_UINT(orig_interval, orig_interval, S_IRUGO | S_IWUSR,
 		     2 * BATADV_JITTER, INT_MAX, NULL);
 BATADV_ATTR_SIF_UINT(hop_penalty, hop_penalty, S_IRUGO | S_IWUSR, 0,
 		     BATADV_TQ_MAX_VALUE, NULL);
-BATADV_ATTR_SIF_UINT(gw_sel_class, gw.sel_class, S_IRUGO | S_IWUSR, 1,
-		     BATADV_TQ_MAX_VALUE, batadv_post_gw_reselect);
+static BATADV_ATTR(gw_sel_class, S_IRUGO | S_IWUSR, batadv_show_gw_sel_class,
+		   batadv_store_gw_sel_class);
 static BATADV_ATTR(gw_bandwidth, S_IRUGO | S_IWUSR, batadv_show_gw_bwidth,
 		   batadv_store_gw_bwidth);
 #ifdef CONFIG_BATMAN_ADV_MCAST
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index 4d6a7ce..ea7ad8c 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -1446,12 +1446,24 @@ struct batadv_algo_orig_ops {
 };
 
 /**
+ * struct batadv_algo_gw_ops - mesh algorithm callbacks (GW specific)
+ * @store_sel_class: parse and stores a new GW selection class
+ * @show_sel_class: prints the current GW selection class
+ */
+struct batadv_algo_gw_ops {
+	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);
+};
+
+/**
  * struct batadv_algo_ops - mesh algorithm callbacks
  * @list: list node for the batadv_algo_list
  * @name: name of the algorithm
  * @iface: callbacks related to interface handling
  * @neigh: callbacks related to neighbors handling
  * @orig: callbacks related to originators handling
+ * @gw: callbacks related to GW mode
  */
 struct batadv_algo_ops {
 	struct hlist_node list;
@@ -1459,6 +1471,7 @@ struct batadv_algo_ops {
 	struct batadv_algo_iface_ops iface;
 	struct batadv_algo_neigh_ops neigh;
 	struct batadv_algo_orig_ops orig;
+	struct batadv_algo_gw_ops gw;
 };
 
 /**
-- 
2.8.3

[B.A.T.M.A.N.] [PATCH v4 3/6] batman-adv: statically print gateway table header

[Antonio Quartulli]

To make it easier to search through the code it is better to print static
strings directly instead of using format strings printing constants.

This was addressed in a previous patch, but the Gateway table header
was not updated accordingly.

Signed-off-by: Antonio Quartulli <a@unstable.cc>
---
 net/batman-adv/gateway_client.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index e108d45..63a805d 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -639,8 +639,7 @@ int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
 		goto out;
 
 	seq_printf(seq,
-		   "      %-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",
+		   "      Gateway      (#/255)           Nexthop [outgoingIF]: advertised uplink bandwidth ... [B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
 		   BATADV_SOURCE_VERSION, primary_if->net_dev->name,
 		   primary_if->net_dev->dev_addr, net_dev->name);
 
-- 
2.8.3

[B.A.T.M.A.N.] [PATCH v4 4/6] batman-adv: make GW election code protocol specific

[Antonio Quartulli]

Each routing protocol may have its own specific logic about
gateway election which is potentially based on the metric being
used.

Create two GW specific API functions and move the current election
logic in the B.A.T.M.A.N. IV specific code.

Signed-off-by: Antonio Quartulli <a@unstable.cc>
---
 net/batman-adv/bat_iv_ogm.c     | 219 ++++++++++++++++++++++++++++++++++++++++
 net/batman-adv/gateway_client.c | 213 +++++---------------------------------
 net/batman-adv/gateway_client.h |   3 +
 net/batman-adv/gateway_common.c |   5 +-
 net/batman-adv/types.h          |  10 ++
 5 files changed, 258 insertions(+), 192 deletions(-)

diff --git a/net/batman-adv/bat_iv_ogm.c b/net/batman-adv/bat_iv_ogm.c
index 19b0abd..e907492 100644
--- a/net/batman-adv/bat_iv_ogm.c
+++ b/net/batman-adv/bat_iv_ogm.c
@@ -51,6 +51,7 @@
 
 #include "bat_algo.h"
 #include "bitarray.h"
+#include "gateway_client.h"
 #include "hard-interface.h"
 #include "hash.h"
 #include "log.h"
@@ -2117,6 +2118,219 @@ static void batadv_iv_iface_activate(struct batadv_hard_iface *hard_iface)
 	batadv_iv_ogm_schedule(hard_iface);
 }
 
+static struct batadv_gw_node *
+batadv_iv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
+{
+	struct batadv_neigh_node *router;
+	struct batadv_neigh_ifinfo *router_ifinfo;
+	struct batadv_gw_node *gw_node, *curr_gw = NULL;
+	u64 max_gw_factor = 0;
+	u64 tmp_gw_factor = 0;
+	u8 max_tq = 0;
+	u8 tq_avg;
+	struct batadv_orig_node *orig_node;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
+		orig_node = gw_node->orig_node;
+		router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
+		if (!router)
+			continue;
+
+		router_ifinfo = batadv_neigh_ifinfo_get(router,
+							BATADV_IF_DEFAULT);
+		if (!router_ifinfo)
+			goto next;
+
+		if (!kref_get_unless_zero(&gw_node->refcount))
+			goto next;
+
+		tq_avg = router_ifinfo->bat_iv.tq_avg;
+
+		switch (atomic_read(&bat_priv->gw.sel_class)) {
+		case 1: /* fast connection */
+			tmp_gw_factor = tq_avg * tq_avg;
+			tmp_gw_factor *= gw_node->bandwidth_down;
+			tmp_gw_factor *= 100 * 100;
+			tmp_gw_factor >>= 18;
+
+			if ((tmp_gw_factor > max_gw_factor) ||
+			    ((tmp_gw_factor == max_gw_factor) &&
+			     (tq_avg > max_tq))) {
+				if (curr_gw)
+					batadv_gw_node_put(curr_gw);
+				curr_gw = gw_node;
+				kref_get(&curr_gw->refcount);
+			}
+			break;
+
+		default: /* 2:  stable connection (use best statistic)
+			  * 3:  fast-switch (use best statistic but change as
+			  *     soon as a better gateway appears)
+			  * XX: late-switch (use best statistic but change as
+			  *     soon as a better gateway appears which has
+			  *     $routing_class more tq points)
+			  */
+			if (tq_avg > max_tq) {
+				if (curr_gw)
+					batadv_gw_node_put(curr_gw);
+				curr_gw = gw_node;
+				kref_get(&curr_gw->refcount);
+			}
+			break;
+		}
+
+		if (tq_avg > max_tq)
+			max_tq = tq_avg;
+
+		if (tmp_gw_factor > max_gw_factor)
+			max_gw_factor = tmp_gw_factor;
+
+		batadv_gw_node_put(gw_node);
+
+next:
+		batadv_neigh_node_put(router);
+		if (router_ifinfo)
+			batadv_neigh_ifinfo_put(router_ifinfo);
+	}
+	rcu_read_unlock();
+
+	return curr_gw;
+}
+
+static bool batadv_iv_gw_is_eligible(struct batadv_priv *bat_priv,
+				     struct batadv_orig_node *curr_gw_orig,
+				     struct batadv_orig_node *orig_node)
+{
+	struct batadv_neigh_ifinfo *router_orig_ifinfo = NULL;
+	struct batadv_neigh_ifinfo *router_gw_ifinfo = NULL;
+	struct batadv_neigh_node *router_gw = NULL;
+	struct batadv_neigh_node *router_orig = NULL;
+	u8 gw_tq_avg, orig_tq_avg;
+	bool ret = false;
+
+	/* dynamic re-election is performed only on fast or late switch */
+	if (atomic_read(&bat_priv->gw.sel_class) <= 2)
+		return false;
+
+	router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT);
+	if (!router_gw) {
+		ret = true;
+		goto out;
+	}
+
+	router_gw_ifinfo = batadv_neigh_ifinfo_get(router_gw,
+						   BATADV_IF_DEFAULT);
+	if (!router_gw_ifinfo) {
+		ret = true;
+		goto out;
+	}
+
+	router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
+	if (!router_orig)
+		goto out;
+
+	router_orig_ifinfo = batadv_neigh_ifinfo_get(router_orig,
+						     BATADV_IF_DEFAULT);
+	if (!router_orig_ifinfo)
+		goto out;
+
+	gw_tq_avg = router_gw_ifinfo->bat_iv.tq_avg;
+	orig_tq_avg = router_orig_ifinfo->bat_iv.tq_avg;
+
+	/* the TQ value has to be better */
+	if (orig_tq_avg < gw_tq_avg)
+		goto out;
+
+	/* if the routing class is greater than 3 the value tells us how much
+	 * greater the TQ value of the new gateway must be
+	 */
+	if ((atomic_read(&bat_priv->gw.sel_class) > 3) &&
+	    (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw.sel_class)))
+		goto out;
+
+	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+		   "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n",
+		   gw_tq_avg, orig_tq_avg);
+
+	ret = true;
+out:
+	if (router_gw_ifinfo)
+		batadv_neigh_ifinfo_put(router_gw_ifinfo);
+	if (router_orig_ifinfo)
+		batadv_neigh_ifinfo_put(router_orig_ifinfo);
+	if (router_gw)
+		batadv_neigh_node_put(router_gw);
+	if (router_orig)
+		batadv_neigh_node_put(router_orig);
+
+	return ret;
+}
+
+/* fails if orig_node has no router */
+static int batadv_iv_gw_write_buffer_text(struct batadv_priv *bat_priv,
+					  struct seq_file *seq,
+					  const struct batadv_gw_node *gw_node)
+{
+	struct batadv_gw_node *curr_gw;
+	struct batadv_neigh_node *router;
+	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
+	int ret = -1;
+
+	router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
+	if (!router)
+		goto out;
+
+	router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
+	if (!router_ifinfo)
+		goto out;
+
+	curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
+
+	seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %u.%u/%u.%u MBit\n",
+		   (curr_gw == gw_node ? "=>" : "  "),
+		   gw_node->orig_node->orig,
+		   router_ifinfo->bat_iv.tq_avg, router->addr,
+		   router->if_incoming->net_dev->name,
+		   gw_node->bandwidth_down / 10,
+		   gw_node->bandwidth_down % 10,
+		   gw_node->bandwidth_up / 10,
+		   gw_node->bandwidth_up % 10);
+	ret = seq_has_overflowed(seq) ? -1 : 0;
+
+	if (curr_gw)
+		batadv_gw_node_put(curr_gw);
+out:
+	if (router_ifinfo)
+		batadv_neigh_ifinfo_put(router_ifinfo);
+	if (router)
+		batadv_neigh_node_put(router);
+	return ret;
+}
+
+static void batadv_iv_gw_print(struct batadv_priv *bat_priv,
+			       struct seq_file *seq)
+{
+	struct batadv_gw_node *gw_node;
+	int gw_count = 0;
+
+	seq_printf(seq,
+		   "      Gateway      (#/255)           Nexthop [outgoingIF]: advertised uplink bandwidth\n");
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
+		/* fails if orig_node has no router */
+		if (batadv_iv_gw_write_buffer_text(bat_priv, seq, gw_node) < 0)
+			continue;
+
+		gw_count++;
+	}
+	rcu_read_unlock();
+
+	if (gw_count == 0)
+		seq_puts(seq, "No gateways in range ...\n");
+}
+
 static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
 	.name = "BATMAN_IV",
 	.iface = {
@@ -2137,6 +2351,11 @@ static struct batadv_algo_ops batadv_batman_iv __read_mostly = {
 		.add_if = batadv_iv_ogm_orig_add_if,
 		.del_if = batadv_iv_ogm_orig_del_if,
 	},
+	.gw = {
+		.get_best_gw_node = batadv_iv_gw_get_best_gw_node,
+		.is_eligible = batadv_iv_gw_is_eligible,
+		.print = batadv_iv_gw_print,
+	},
 };
 
 int __init batadv_iv_init(void)
diff --git a/net/batman-adv/gateway_client.c b/net/batman-adv/gateway_client.c
index 63a805d..564f9d9 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -80,12 +80,12 @@ static void batadv_gw_node_release(struct kref *ref)
  * batadv_gw_node_put - decrement the gw_node refcounter and possibly release it
  * @gw_node: gateway node to free
  */
-static void batadv_gw_node_put(struct batadv_gw_node *gw_node)
+void batadv_gw_node_put(struct batadv_gw_node *gw_node)
 {
 	kref_put(&gw_node->refcount, batadv_gw_node_release);
 }
 
-static struct batadv_gw_node *
+struct batadv_gw_node *
 batadv_gw_get_selected_gw_node(struct batadv_priv *bat_priv)
 {
 	struct batadv_gw_node *gw_node;
@@ -164,86 +164,6 @@ void batadv_gw_reselect(struct batadv_priv *bat_priv)
 	atomic_set(&bat_priv->gw.reselect, 1);
 }
 
-static struct batadv_gw_node *
-batadv_gw_get_best_gw_node(struct batadv_priv *bat_priv)
-{
-	struct batadv_neigh_node *router;
-	struct batadv_neigh_ifinfo *router_ifinfo;
-	struct batadv_gw_node *gw_node, *curr_gw = NULL;
-	u64 max_gw_factor = 0;
-	u64 tmp_gw_factor = 0;
-	u8 max_tq = 0;
-	u8 tq_avg;
-	struct batadv_orig_node *orig_node;
-
-	rcu_read_lock();
-	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
-		orig_node = gw_node->orig_node;
-		router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
-		if (!router)
-			continue;
-
-		router_ifinfo = batadv_neigh_ifinfo_get(router,
-							BATADV_IF_DEFAULT);
-		if (!router_ifinfo)
-			goto next;
-
-		if (!kref_get_unless_zero(&gw_node->refcount))
-			goto next;
-
-		tq_avg = router_ifinfo->bat_iv.tq_avg;
-
-		switch (atomic_read(&bat_priv->gw.sel_class)) {
-		case 1: /* fast connection */
-			tmp_gw_factor = tq_avg * tq_avg;
-			tmp_gw_factor *= gw_node->bandwidth_down;
-			tmp_gw_factor *= 100 * 100;
-			tmp_gw_factor >>= 18;
-
-			if ((tmp_gw_factor > max_gw_factor) ||
-			    ((tmp_gw_factor == max_gw_factor) &&
-			     (tq_avg > max_tq))) {
-				if (curr_gw)
-					batadv_gw_node_put(curr_gw);
-				curr_gw = gw_node;
-				kref_get(&curr_gw->refcount);
-			}
-			break;
-
-		default: /* 2:  stable connection (use best statistic)
-			  * 3:  fast-switch (use best statistic but change as
-			  *     soon as a better gateway appears)
-			  * XX: late-switch (use best statistic but change as
-			  *     soon as a better gateway appears which has
-			  *     $routing_class more tq points)
-			  */
-			if (tq_avg > max_tq) {
-				if (curr_gw)
-					batadv_gw_node_put(curr_gw);
-				curr_gw = gw_node;
-				kref_get(&curr_gw->refcount);
-			}
-			break;
-		}
-
-		if (tq_avg > max_tq)
-			max_tq = tq_avg;
-
-		if (tmp_gw_factor > max_gw_factor)
-			max_gw_factor = tmp_gw_factor;
-
-		batadv_gw_node_put(gw_node);
-
-next:
-		batadv_neigh_node_put(router);
-		if (router_ifinfo)
-			batadv_neigh_ifinfo_put(router_ifinfo);
-	}
-	rcu_read_unlock();
-
-	return curr_gw;
-}
-
 /**
  * batadv_gw_check_client_stop - check if client mode has been switched off
  * @bat_priv: the bat priv with all the soft interface information
@@ -287,12 +207,15 @@ void batadv_gw_election(struct batadv_priv *bat_priv)
 	if (atomic_read(&bat_priv->gw.mode) != BATADV_GW_MODE_CLIENT)
 		goto out;
 
+	if (!bat_priv->algo_ops->gw.get_best_gw_node)
+		goto out;
+
 	curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
 
 	if (!batadv_atomic_dec_not_zero(&bat_priv->gw.reselect) && curr_gw)
 		goto out;
 
-	next_gw = batadv_gw_get_best_gw_node(bat_priv);
+	next_gw = bat_priv->algo_ops->gw.get_best_gw_node(bat_priv);
 
 	if (curr_gw == next_gw)
 		goto out;
@@ -360,70 +283,31 @@ out:
 void batadv_gw_check_election(struct batadv_priv *bat_priv,
 			      struct batadv_orig_node *orig_node)
 {
-	struct batadv_neigh_ifinfo *router_orig_tq = NULL;
-	struct batadv_neigh_ifinfo *router_gw_tq = NULL;
 	struct batadv_orig_node *curr_gw_orig;
-	struct batadv_neigh_node *router_gw = NULL;
-	struct batadv_neigh_node *router_orig = NULL;
-	u8 gw_tq_avg, orig_tq_avg;
+
+	/* abort immediately if the routing algorithm does not support gateway
+	 * election
+	 */
+	if (!bat_priv->algo_ops->gw.is_eligible)
+		return;
 
 	curr_gw_orig = batadv_gw_get_selected_orig(bat_priv);
 	if (!curr_gw_orig)
 		goto reselect;
 
-	router_gw = batadv_orig_router_get(curr_gw_orig, BATADV_IF_DEFAULT);
-	if (!router_gw)
-		goto reselect;
-
-	router_gw_tq = batadv_neigh_ifinfo_get(router_gw,
-					       BATADV_IF_DEFAULT);
-	if (!router_gw_tq)
-		goto reselect;
-
 	/* this node already is the gateway */
 	if (curr_gw_orig == orig_node)
 		goto out;
 
-	router_orig = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
-	if (!router_orig)
-		goto out;
-
-	router_orig_tq = batadv_neigh_ifinfo_get(router_orig,
-						 BATADV_IF_DEFAULT);
-	if (!router_orig_tq)
-		goto out;
-
-	gw_tq_avg = router_gw_tq->bat_iv.tq_avg;
-	orig_tq_avg = router_orig_tq->bat_iv.tq_avg;
-
-	/* the TQ value has to be better */
-	if (orig_tq_avg < gw_tq_avg)
+	if (!bat_priv->algo_ops->gw.is_eligible(bat_priv, curr_gw_orig,
+						orig_node))
 		goto out;
 
-	/* if the routing class is greater than 3 the value tells us how much
-	 * greater the TQ value of the new gateway must be
-	 */
-	if ((atomic_read(&bat_priv->gw.sel_class) > 3) &&
-	    (orig_tq_avg - gw_tq_avg < atomic_read(&bat_priv->gw.sel_class)))
-		goto out;
-
-	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-		   "Restarting gateway selection: better gateway found (tq curr: %i, tq new: %i)\n",
-		   gw_tq_avg, orig_tq_avg);
-
 reselect:
 	batadv_gw_reselect(bat_priv);
 out:
 	if (curr_gw_orig)
 		batadv_orig_node_put(curr_gw_orig);
-	if (router_gw)
-		batadv_neigh_node_put(router_gw);
-	if (router_orig)
-		batadv_neigh_node_put(router_orig);
-	if (router_gw_tq)
-		batadv_neigh_ifinfo_put(router_gw_tq);
-	if (router_orig_tq)
-		batadv_neigh_ifinfo_put(router_orig_tq);
 }
 
 /**
@@ -585,80 +469,31 @@ void batadv_gw_node_free(struct batadv_priv *bat_priv)
 	spin_unlock_bh(&bat_priv->gw.list_lock);
 }
 
-/* fails if orig_node has no router */
-static int batadv_write_buffer_text(struct batadv_priv *bat_priv,
-				    struct seq_file *seq,
-				    const struct batadv_gw_node *gw_node)
-{
-	struct batadv_gw_node *curr_gw;
-	struct batadv_neigh_node *router;
-	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
-	int ret = -1;
-
-	router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
-	if (!router)
-		goto out;
-
-	router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
-	if (!router_ifinfo)
-		goto out;
-
-	curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
-
-	seq_printf(seq, "%s %pM (%3i) %pM [%10s]: %u.%u/%u.%u MBit\n",
-		   (curr_gw == gw_node ? "=>" : "  "),
-		   gw_node->orig_node->orig,
-		   router_ifinfo->bat_iv.tq_avg, router->addr,
-		   router->if_incoming->net_dev->name,
-		   gw_node->bandwidth_down / 10,
-		   gw_node->bandwidth_down % 10,
-		   gw_node->bandwidth_up / 10,
-		   gw_node->bandwidth_up % 10);
-	ret = seq_has_overflowed(seq) ? -1 : 0;
-
-	if (curr_gw)
-		batadv_gw_node_put(curr_gw);
-out:
-	if (router_ifinfo)
-		batadv_neigh_ifinfo_put(router_ifinfo);
-	if (router)
-		batadv_neigh_node_put(router);
-	return ret;
-}
-
 int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset)
 {
 	struct net_device *net_dev = (struct net_device *)seq->private;
 	struct batadv_priv *bat_priv = netdev_priv(net_dev);
 	struct batadv_hard_iface *primary_if;
-	struct batadv_gw_node *gw_node;
-	int gw_count = 0;
 
 	primary_if = batadv_seq_print_text_primary_if_get(seq);
 	if (!primary_if)
-		goto out;
+		return 0;
 
-	seq_printf(seq,
-		   "      Gateway      (#/255)           Nexthop [outgoingIF]: advertised uplink bandwidth ... [B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s)]\n",
+	seq_printf(seq, "[B.A.T.M.A.N. adv %s, MainIF/MAC: %s/%pM (%s %s)]\n",
 		   BATADV_SOURCE_VERSION, primary_if->net_dev->name,
-		   primary_if->net_dev->dev_addr, net_dev->name);
+		   primary_if->net_dev->dev_addr, net_dev->name,
+		   bat_priv->algo_ops->name);
 
-	rcu_read_lock();
-	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
-		/* fails if orig_node has no router */
-		if (batadv_write_buffer_text(bat_priv, seq, gw_node) < 0)
-			continue;
+	batadv_hardif_put(primary_if);
 
-		gw_count++;
+	if (!bat_priv->algo_ops->gw.print) {
+		seq_puts(seq,
+			 "No printing function for this routing protocol\n");
+		return 0;
 	}
-	rcu_read_unlock();
 
-	if (gw_count == 0)
-		seq_puts(seq, "No gateways in range ...\n");
+	bat_priv->algo_ops->gw.print(bat_priv, seq);
 
-out:
-	if (primary_if)
-		batadv_hardif_put(primary_if);
 	return 0;
 }
 
diff --git a/net/batman-adv/gateway_client.h b/net/batman-adv/gateway_client.h
index 582dd8c..4c9edde 100644
--- a/net/batman-adv/gateway_client.h
+++ b/net/batman-adv/gateway_client.h
@@ -39,6 +39,9 @@ void batadv_gw_node_update(struct batadv_priv *bat_priv,
 void batadv_gw_node_delete(struct batadv_priv *bat_priv,
 			   struct batadv_orig_node *orig_node);
 void batadv_gw_node_free(struct batadv_priv *bat_priv);
+void batadv_gw_node_put(struct batadv_gw_node *gw_node);
+struct batadv_gw_node *
+batadv_gw_get_selected_gw_node(struct batadv_priv *bat_priv);
 int batadv_gw_client_seq_print_text(struct seq_file *seq, void *offset);
 bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, struct sk_buff *skb);
 enum batadv_dhcp_recipient
diff --git a/net/batman-adv/gateway_common.c b/net/batman-adv/gateway_common.c
index d7bc6a8..2118481 100644
--- a/net/batman-adv/gateway_common.c
+++ b/net/batman-adv/gateway_common.c
@@ -241,10 +241,9 @@ static void batadv_gw_tvlv_ogm_handler_v1(struct batadv_priv *bat_priv,
 
 	batadv_gw_node_update(bat_priv, orig, &gateway);
 
-	/* restart gateway selection if fast or late switching was enabled */
+	/* restart gateway selection */
 	if ((gateway.bandwidth_down != 0) &&
-	    (atomic_read(&bat_priv->gw.mode) == BATADV_GW_MODE_CLIENT) &&
-	    (atomic_read(&bat_priv->gw.sel_class) > 2))
+	    (atomic_read(&bat_priv->gw.mode) == BATADV_GW_MODE_CLIENT))
 		batadv_gw_check_election(bat_priv, orig);
 }
 
diff --git a/net/batman-adv/types.h b/net/batman-adv/types.h
index ea7ad8c..999ecb5 100644
--- a/net/batman-adv/types.h
+++ b/net/batman-adv/types.h
@@ -1449,11 +1449,21 @@ struct batadv_algo_orig_ops {
  * struct batadv_algo_gw_ops - mesh algorithm callbacks (GW specific)
  * @store_sel_class: parse and stores a new GW selection class
  * @show_sel_class: prints the current GW selection class
+ * @get_best_gw_node: select the best GW from the list of available nodes
+ * @is_eligible: check if a newly discovered GW is a potential candidate for
+ *  the election as best GW
+ * @print: print the gateway table (optional)
  */
 struct batadv_algo_gw_ops {
 	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);
+	struct batadv_gw_node *(*get_best_gw_node)
+		(struct batadv_priv *bat_priv);
+	bool (*is_eligible)(struct batadv_priv *bat_priv,
+			    struct batadv_orig_node *curr_gw_orig,
+			    struct batadv_orig_node *orig_node);
+	void (*print)(struct batadv_priv *bat_priv, struct seq_file *seq);
 };
 
 /**
-- 
2.8.3

[B.A.T.M.A.N.] [PATCH v4 5/6] batman-adv: B.A.T.M.A.N. V - implement GW selection logic

[Antonio Quartulli]

Since the GW selection logic has been made routing protocol specific
it is now possible for B.A.T.M.A.N V to have its own mechanism by
providing the API implementation.

Implement the GW specific API in the B.A.T.M.A.N. V protocol in
order to provide a working GW selection mechanism.

Signed-off-by: Antonio Quartulli <a@unstable.cc>
---
 net/batman-adv/bat_v.c          | 220 +++++++++++++++++++++++++++++++++++++++-
 net/batman-adv/gateway_client.c |   9 +-
 net/batman-adv/gateway_client.h |   4 +
 3 files changed, 229 insertions(+), 4 deletions(-)

diff --git a/net/batman-adv/bat_v.c b/net/batman-adv/bat_v.c
index 3066e59..175c37c 100644
--- a/net/batman-adv/bat_v.c
+++ b/net/batman-adv/bat_v.c
@@ -24,6 +24,7 @@
 #include <linux/init.h>
 #include <linux/jiffies.h>
 #include <linux/kernel.h>
+#include <linux/kref.h>
 #include <linux/netdevice.h>
 #include <linux/rculist.h>
 #include <linux/rcupdate.h>
@@ -39,6 +40,7 @@
 #include "gateway_common.h"
 #include "hard-interface.h"
 #include "hash.h"
+#include "log.h"
 #include "originator.h"
 #include "packet.h"
 
@@ -349,6 +351,210 @@ static ssize_t batadv_v_show_sel_class(struct batadv_priv *bat_priv, char *buff)
 	return sprintf(buff, "%u.%u MBit\n", class / 10, class % 10);
 }
 
+/**
+ * batadv_v_gw_throughput_get - retrieve the GW-bandwidth for a given GW
+ * @gw_node: the GW to retrieve the metric for
+ * @bw: the pointer where the metric will be stored. The metric is computed as
+ *  the minimum between the GW advertised throughput and the path throughput to
+ *  it in the mesh
+ *
+ * Return: 0 on success, -1 on failure
+ */
+static int batadv_v_gw_throughput_get(struct batadv_gw_node *gw_node, u32 *bw)
+{
+	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
+	struct batadv_orig_node *orig_node;
+	struct batadv_neigh_node *router;
+	int ret = -1;
+
+	orig_node = gw_node->orig_node;
+	router = batadv_orig_router_get(orig_node, BATADV_IF_DEFAULT);
+	if (!router)
+		goto out;
+
+	router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
+	if (!router_ifinfo)
+		goto out;
+
+	/* the GW metric is computed as the minimum between the path throughput
+	 * to reach the GW itself and the advertised bandwidth.
+	 * This gives us an approximation of the effective throughput that the
+	 * client can expect via this particular GW node
+	 */
+	*bw = router_ifinfo->bat_v.throughput;
+	*bw = min_t(u32, *bw, gw_node->bandwidth_down);
+
+	ret = 0;
+out:
+	if (router)
+		batadv_neigh_node_put(router);
+	if (router_ifinfo)
+		batadv_neigh_ifinfo_put(router_ifinfo);
+
+	return ret;
+}
+
+/**
+ * batadv_v_gw_get_best_gw_node - retrieve the best GW node
+ * @bat_priv: the bat priv with all the soft interface information
+ *
+ * Return: the GW node having the best GW-metric, NULL if no GW is known
+ */
+static struct batadv_gw_node *
+batadv_v_gw_get_best_gw_node(struct batadv_priv *bat_priv)
+{
+	struct batadv_gw_node *gw_node, *curr_gw = NULL;
+	u32 max_bw = 0, bw;
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
+		if (!kref_get_unless_zero(&gw_node->refcount))
+			continue;
+
+		if (batadv_v_gw_throughput_get(gw_node, &bw) < 0)
+			goto next;
+
+		if (curr_gw && (bw <= max_bw))
+			goto next;
+
+		if (curr_gw)
+			batadv_gw_node_put(curr_gw);
+
+		curr_gw = gw_node;
+		kref_get(&curr_gw->refcount);
+		max_bw = bw;
+
+next:
+		batadv_gw_node_put(gw_node);
+	}
+	rcu_read_unlock();
+
+	return curr_gw;
+}
+
+/**
+ * batadv_v_gw_is_eligible - check if a originator would be selected as GW
+ * @bat_priv: the bat priv with all the soft interface information
+ * @curr_gw_orig: originator representing the currently selected GW
+ * @orig_node: the originator representing the new candidate
+ *
+ * Return: true if orig_node can be selected as current GW, false otherwise
+ */
+static bool batadv_v_gw_is_eligible(struct batadv_priv *bat_priv,
+				    struct batadv_orig_node *curr_gw_orig,
+				    struct batadv_orig_node *orig_node)
+{
+	struct batadv_gw_node *curr_gw = NULL, *orig_gw = NULL;
+	u32 gw_throughput, orig_throughput, threshold;
+	bool ret = false;
+
+	threshold = atomic_read(&bat_priv->gw.sel_class);
+
+	curr_gw = batadv_gw_node_get(bat_priv, curr_gw_orig);
+	if (!curr_gw) {
+		ret = true;
+		goto out;
+	}
+
+	if (batadv_v_gw_throughput_get(curr_gw, &gw_throughput) < 0) {
+		ret = true;
+		goto out;
+	}
+
+	orig_gw = batadv_gw_node_get(bat_priv, orig_node);
+	if (!orig_node)
+		goto out;
+
+	if (batadv_v_gw_throughput_get(orig_gw, &orig_throughput) < 0)
+		goto out;
+
+	if (orig_throughput < (gw_throughput + threshold))
+		goto out;
+
+	batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+		   "Restarting gateway selection: better gateway found (throughput curr: %u, throughput new: %u)\n",
+		   gw_throughput, orig_throughput);
+
+	ret = true;
+out:
+	if (curr_gw)
+		batadv_gw_node_put(curr_gw);
+	if (orig_gw)
+		batadv_gw_node_put(orig_gw);
+
+	return ret;
+}
+
+/* fails if orig_node has no router */
+static int batadv_v_gw_write_buffer_text(struct batadv_priv *bat_priv,
+					 struct seq_file *seq,
+					 const struct batadv_gw_node *gw_node)
+{
+	struct batadv_gw_node *curr_gw;
+	struct batadv_neigh_node *router;
+	struct batadv_neigh_ifinfo *router_ifinfo = NULL;
+	int ret = -1;
+
+	router = batadv_orig_router_get(gw_node->orig_node, BATADV_IF_DEFAULT);
+	if (!router)
+		goto out;
+
+	router_ifinfo = batadv_neigh_ifinfo_get(router, BATADV_IF_DEFAULT);
+	if (!router_ifinfo)
+		goto out;
+
+	curr_gw = batadv_gw_get_selected_gw_node(bat_priv);
+
+	seq_printf(seq, "%s %pM (%9u.%1u) %pM [%10s]: %u.%u/%u.%u MBit\n",
+		   (curr_gw == gw_node ? "=>" : "  "),
+		   gw_node->orig_node->orig,
+		   router_ifinfo->bat_v.throughput / 10,
+		   router_ifinfo->bat_v.throughput % 10, router->addr,
+		   router->if_incoming->net_dev->name,
+		   gw_node->bandwidth_down / 10,
+		   gw_node->bandwidth_down % 10,
+		   gw_node->bandwidth_up / 10,
+		   gw_node->bandwidth_up % 10);
+	ret = seq_has_overflowed(seq) ? -1 : 0;
+
+	if (curr_gw)
+		batadv_gw_node_put(curr_gw);
+out:
+	if (router_ifinfo)
+		batadv_neigh_ifinfo_put(router_ifinfo);
+	if (router)
+		batadv_neigh_node_put(router);
+	return ret;
+}
+
+/**
+ * batadv_v_gw_print - print the gateway list
+ * @bat_priv: the bat priv with all the soft interface information
+ * @seq: gateway table seq_file struct
+ */
+static void batadv_v_gw_print(struct batadv_priv *bat_priv,
+			      struct seq_file *seq)
+{
+	struct batadv_gw_node *gw_node;
+	int gw_count = 0;
+
+	seq_printf(seq,
+		   "      Gateway        ( throughput)           Nexthop [outgoingIF]: advertised uplink bandwidth\n");
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(gw_node, &bat_priv->gw.list, list) {
+		/* fails if orig_node has no router */
+		if (batadv_v_gw_write_buffer_text(bat_priv, seq, gw_node) < 0)
+			continue;
+
+		gw_count++;
+	}
+	rcu_read_unlock();
+
+	if (gw_count == 0)
+		seq_puts(seq, "No gateways in range ...\n");
+}
+
 static struct batadv_algo_ops batadv_batman_v __read_mostly = {
 	.name = "BATMAN_V",
 	.iface = {
@@ -370,6 +576,9 @@ static struct batadv_algo_ops batadv_batman_v __read_mostly = {
 	.gw = {
 		.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,
+		.is_eligible = batadv_v_gw_is_eligible,
+		.print = batadv_v_gw_print,
 	},
 };
 
@@ -382,7 +591,16 @@ static struct batadv_algo_ops batadv_batman_v __read_mostly = {
  */
 int batadv_v_mesh_init(struct batadv_priv *bat_priv)
 {
-	return batadv_v_ogm_init(bat_priv);
+	int ret = 0;
+
+	ret = batadv_v_ogm_init(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/gateway_client.c b/net/batman-adv/gateway_client.c
index 564f9d9..a77a179 100644
--- a/net/batman-adv/gateway_client.c
+++ b/net/batman-adv/gateway_client.c
@@ -215,6 +215,10 @@ void batadv_gw_election(struct batadv_priv *bat_priv)
 	if (!batadv_atomic_dec_not_zero(&bat_priv->gw.reselect) && curr_gw)
 		goto out;
 
+	/* if gw.reselect is set to 1 it means that a previous call to
+	 * gw.is_eligible() said that we have a new best GW, therefore it can
+	 * now be picked from the list and selected
+	 */
 	next_gw = bat_priv->algo_ops->gw.get_best_gw_node(bat_priv);
 
 	if (curr_gw == next_gw)
@@ -356,9 +360,8 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv,
  *
  * Return: 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 *batadv_gw_node_get(struct batadv_priv *bat_priv,
+					  struct batadv_orig_node *orig_node)
 {
 	struct batadv_gw_node *gw_node_tmp, *gw_node = NULL;
 
diff --git a/net/batman-adv/gateway_client.h b/net/batman-adv/gateway_client.h
index 4c9edde..00fa434 100644
--- a/net/batman-adv/gateway_client.h
+++ b/net/batman-adv/gateway_client.h
@@ -47,5 +47,9 @@ bool batadv_gw_out_of_range(struct batadv_priv *bat_priv, struct sk_buff *skb);
 enum batadv_dhcp_recipient
 batadv_gw_dhcp_recipient_get(struct sk_buff *skb, unsigned int *header_len,
 			     u8 *chaddr);
+#ifdef CONFIG_BATMAN_ADV_BATMAN_V
+struct batadv_gw_node *batadv_gw_node_get(struct batadv_priv *bat_priv,
+					  struct batadv_orig_node *orig_node);
+#endif /* CONFIG_BATMAN_ADV_BATMAN_V */
 
 #endif /* _NET_BATMAN_ADV_GATEWAY_CLIENT_H_ */
-- 
2.8.3

[B.A.T.M.A.N.] [PATCH v4 6/6] batman-adv: disable sysfs knobs when GW-mode is not implemented

[Antonio Quartulli]

Now that the GW-mode code is algorithm specific, batman-adv expects the
routing algorithm to implement some APIs to make it work.

However, such APIs are not mandatory, therefore we might have algorithms
not providing them. In this case all the sysfs knobs related to GW-mode
should be deactivated to make sure that settings injected by the user
for this feature are rejected.

Signed-off-by: Antonio Quartulli <a@unstable.cc>
---
 net/batman-adv/sysfs.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

diff --git a/net/batman-adv/sysfs.c b/net/batman-adv/sysfs.c
index bb43742..486fdd6 100644
--- a/net/batman-adv/sysfs.c
+++ b/net/batman-adv/sysfs.c
@@ -428,6 +428,13 @@ static ssize_t batadv_show_gw_mode(struct kobject *kobj, struct attribute *attr,
 	struct batadv_priv *bat_priv = batadv_kobj_to_batpriv(kobj);
 	int bytes_written;
 
+	/* GW mode is not available if the routing algorithm in use does not
+	 * implement the GW API
+	 */
+	if (!bat_priv->algo_ops->gw.get_best_gw_node ||
+	    !bat_priv->algo_ops->gw.is_eligible)
+		return -ENOENT;
+
 	switch (atomic_read(&bat_priv->gw.mode)) {
 	case BATADV_GW_MODE_CLIENT:
 		bytes_written = sprintf(buff, "%s\n",
@@ -455,6 +462,13 @@ static ssize_t batadv_store_gw_mode(struct kobject *kobj,
 	char *curr_gw_mode_str;
 	int gw_mode_tmp = -1;
 
+	/* toggling GW mode is allowed only if the routing algorithm in use
+	 * provides the GW API
+	 */
+	if (!bat_priv->algo_ops->gw.get_best_gw_node ||
+	    !bat_priv->algo_ops->gw.is_eligible)
+		return -EINVAL;
+
 	if (buff[count - 1] == '\n')
 		buff[count - 1] = '\0';
 
@@ -519,6 +533,13 @@ static ssize_t batadv_show_gw_sel_class(struct kobject *kobj,
 {
 	struct batadv_priv *bat_priv = batadv_kobj_to_batpriv(kobj);
 
+	/* GW selection class is not available if the routing algorithm in use
+	 * does not implement the GW API
+	 */
+	if (!bat_priv->algo_ops->gw.get_best_gw_node ||
+	    !bat_priv->algo_ops->gw.is_eligible)
+		return -ENOENT;
+
 	if (bat_priv->algo_ops->gw.show_sel_class)
 		return bat_priv->algo_ops->gw.show_sel_class(bat_priv, buff);
 
@@ -531,6 +552,13 @@ static ssize_t batadv_store_gw_sel_class(struct kobject *kobj,
 {
 	struct batadv_priv *bat_priv = batadv_kobj_to_batpriv(kobj);
 
+	/* setting the GW selection class is allowed only if the routing
+	 * algorithm in use implements the GW API
+	 */
+	if (!bat_priv->algo_ops->gw.get_best_gw_node ||
+	    !bat_priv->algo_ops->gw.is_eligible)
+		return -EINVAL;
+
 	if (buff[count - 1] == '\n')
 		buff[count - 1] = '\0';
 
-- 
2.8.3

Re: [B.A.T.M.A.N.] [PATCH v4 5/6] batman-adv: B.A.T.M.A.N. V - implement GW selection logic

[Sven Eckelmann]

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On Wednesday 25 May 2016 23:27:35 Antonio Quartulli wrote:
> +#ifdef CONFIG_BATMAN_ADV_BATMAN_V
> +struct batadv_gw_node *batadv_gw_node_get(struct batadv_priv *bat_priv,
> +                                         struct batadv_orig_node *orig_node);
> +#endif /* CONFIG_BATMAN_ADV_BATMAN_V */

This is rather odd because the function is also compiled (and used) even when
CONFIG_BATMAN_ADV_BATMAN_V is not enabled.

Here is the relevant diff:

> @@ -356,9 +360,8 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv,
>   *
>   * Return: 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 *batadv_gw_node_get(struct batadv_priv *bat_priv,
> +                                         struct batadv_orig_node *orig_node)
>  {
>         struct batadv_gw_node *gw_node_tmp, *gw_node = NULL;
>  

Maybe you should drop the CONFIG_BATMAN_ADV_BATMAN_V check.

But I should at least whitelist the batadv_gw_node_get for the unused symbols
check.

Kind regards,
	Sven

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Re: [B.A.T.M.A.N.] [PATCH v4 5/6] batman-adv: B.A.T.M.A.N. V - implement GW selection logic

[Antonio Quartulli]

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On Fri, May 27, 2016 at 03:48:37PM +0200, Sven Eckelmann wrote:
> On Wednesday 25 May 2016 23:27:35 Antonio Quartulli wrote:
> > +#ifdef CONFIG_BATMAN_ADV_BATMAN_V
> > +struct batadv_gw_node *batadv_gw_node_get(struct batadv_priv *bat_priv,
> > +                                         struct batadv_orig_node *orig_node);
> > +#endif /* CONFIG_BATMAN_ADV_BATMAN_V */
> 
> This is rather odd because the function is also compiled (and used) even when
> CONFIG_BATMAN_ADV_BATMAN_V is not enabled.
> 
> Here is the relevant diff:
> 
> > @@ -356,9 +360,8 @@ static void batadv_gw_node_add(struct batadv_priv *bat_priv,
> >   *
> >   * Return: 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 *batadv_gw_node_get(struct batadv_priv *bat_priv,
> > +                                         struct batadv_orig_node *orig_node)
> >  {
> >         struct batadv_gw_node *gw_node_tmp, *gw_node = NULL;
> >  
> 
> Maybe you should drop the CONFIG_BATMAN_ADV_BATMAN_V check.
> 
> But I should at least whitelist the batadv_gw_node_get for the unused symbols
> check.

This is exactly the point: when CONFIG_BATMAN_ADV_BATMAN_V is not selected this
exported symbol is not used. Therefore I was not confident if the right way to
go was to put the declaration within the #ifdef block or not..

Do you think it makes more sense to keep the declaration and whitelist the
function in your test ?

Cheers,


-- 
Antonio Quartulli

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Re: [B.A.T.M.A.N.] [PATCH v4 5/6] batman-adv: B.A.T.M.A.N. V - implement GW selection logic

[Sven Eckelmann]

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On Friday 27 May 2016 21:57:29 Antonio Quartulli wrote:
[...]
> Do you think it makes more sense to keep the declaration and whitelist the
> function in your test ?

Yes, this is the right thing(tm) to do. I've already whitelisted it for
the unused-symbol check :)

Otherwise sparse and smatch will scream that the non-static function
has no declaration.

    net/batman-adv/gateway_client.c:363:23: warning: symbol 'batadv_gw_node_get' was not declared. Should it be static?

Kind regards,
	Sven

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Re: [B.A.T.M.A.N.] [PATCH v4 3/6] batman-adv: statically print gateway table header

[Sven Eckelmann]

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On Wednesday 25 May 2016 23:27:33 Antonio Quartulli wrote:
> To make it easier to search through the code it is better to print static
> strings directly instead of using format strings printing constants.
> 
> This was addressed in a previous patch, but the Gateway table header
> was not updated accordingly.
> 
> Signed-off-by: Antonio Quartulli <a@unstable.cc>
> ---

Reviewed-by: Sven Eckelmann <sven@narfation.org>

Kind regards,
	Sven

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Re: [B.A.T.M.A.N.] [PATCH v4 1/6] batman-adv: split routing API data structure in subobjects

[Sven Eckelmann]

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On Wednesday 25 May 2016 23:27:31 Antonio Quartulli wrote:
> The routing API data structure contains several function
> pointers that can easily be grouped together based on the
> component they work with.
> 
> Split the API in subobjects in order to improve definition readability.
> 
> At the same time, remove the "bat_" prefix from the API object and
> its fields names. These are batman-adv private structs and there is no
> need to always prepend such prefix, which only makes function invocations
> much much longer.
> 
> Signed-off-by: Antonio Quartulli <a@unstable.cc>
> ---

My eyes don't want to read diffs anymore which only removes bat_ and replaces
a "_" with a ".". I want more interesting stuff happening in my
movies^Wpatches :)

Reviewed-by: Sven Eckelmann <sven@narfation.org>



Btw. this is rather unrelated to your patch. But the kerneldoc contains
"(optional)" statements. Following functions don't have it (and didn't have it
before your patch):

 * iface.activate
 * neigh.hardif_init
 * orig.free
 * orig.add_if
 * orig.del_if

Kind regards,
	Sven

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Re: [B.A.T.M.A.N.] [PATCH v4 1/6] batman-adv: split routing API data structure in subobjects

[Marek Lindner]

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On Tuesday, May 31, 2016 20:25:16 Sven Eckelmann wrote:
> On Wednesday 25 May 2016 23:27:31 Antonio Quartulli wrote:
> > The routing API data structure contains several function
> > pointers that can easily be grouped together based on the
> > component they work with.
> >
> > Split the API in subobjects in order to improve definition readability.
> >
> > At the same time, remove the "bat_" prefix from the API object and
> > its fields names. These are batman-adv private structs and there is no
> > need to always prepend such prefix, which only makes function invocations
> > much much longer.
> >
> > Signed-off-by: Antonio Quartulli <a@unstable.cc>
> > ---
> 
> My eyes don't want to read diffs anymore which only removes bat_ and
> replaces a "_" with a ".". I want more interesting stuff happening in my
> movies^Wpatches
> 
> Reviewed-by: Sven Eckelmann <sven@narfation.org>

Applied in revision 2297ba1.

Thanks,
Marek

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Re: [B.A.T.M.A.N.] [PATCH v4 3/6] batman-adv: statically print gateway table header

[Marek Lindner]

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On Tuesday, May 31, 2016 19:50:46 Sven Eckelmann wrote:
> On Wednesday 25 May 2016 23:27:33 Antonio Quartulli wrote:
> > To make it easier to search through the code it is better to print static
> > strings directly instead of using format strings printing constants.
> >
> > This was addressed in a previous patch, but the Gateway table header
> > was not updated accordingly.
> >
> > Signed-off-by: Antonio Quartulli <a@unstable.cc>
> > ---
> 
> Reviewed-by: Sven Eckelmann <sven@narfation.org>

Applied in revision f8fa1cf.

Thanks,
Marek

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