0003-batman-adv-introduce-no_rebroadcast-option.patch

From: Matthias Schiffer <mschiffer@universe-factory.net>
Date: Fri, 22 Aug 2014 13:52:42 +0200
Subject: batman-adv: introduce 'no_rebroadcast' option

diff --git a/batman-adv/patches/0001-batman-adv-introduce-no_rebroadcast-option.patch b/batman-adv/patches/0001-batman-adv-introduce-no_rebroadcast-option.patch
new file mode 100644
index 0000000..4f2da9a
--- /dev/null
+++ b/batman-adv/patches/0001-batman-adv-introduce-no_rebroadcast-option.patch
@@ -0,0 +1,185 @@
+From 382460a7114b734581970076d4dfe3011381e339 Mon Sep 17 00:00:00 2001
+Message-Id: <382460a7114b734581970076d4dfe3011381e339.1408708010.git.mschiffer@universe-factory.net>
+From: =?UTF-8?q?Linus=20L=C3=BCssing?= <linus.luessing@web.de>
+Date: Tue, 24 Sep 2013 04:36:27 +0200
+Subject: [PATCH] batman-adv: introduce 'no_rebroadcast' option
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+This patch introduces a new sysfs option named "no_rebroadcast" on
+a per hard interface basis. It allows manually enabling a split-horizon
+like behaviour for the layer 2 multicast payload frames, in that
+incoming multicast payload frames on such a hard interface are only
+being rebroadcasted on all interfaces except the incoming one instead
+of being rebroadcasted on all interfaces.
+
+Such an option should only be enabled if you are certain that these
+rebroadcasts are unnecessary. This is usually the case for instance
+for point-to-point wifi longshots or wired links.
+
+This option can especially safe a significant amount of upload overhead
+if the neighbourhood on a link is rather large, for instance in some
+transitive, symmetric VPN configurations.
+
+Using this option wrongly will break your mesh network, use this option
+wisely and at your own risk!
+
+Signed-off-by: Linus Lüssing <linus.luessing@web.de>
+---
+ hard-interface.c           |  2 ++
+ send.c                     |  4 ++++
+ sysfs-class-net-batman-adv | 10 ++++++++
+ sysfs.c                    | 59 ++++++++++++++++++++++++++++++++++++++++++++++
+ types.h                    |  1 +
+ 5 files changed, 76 insertions(+)
+
+diff --git a/hard-interface.c b/hard-interface.c
+index b851cc5..b222d82 100644
+--- a/hard-interface.c
++++ b/hard-interface.c
+@@ -591,6 +591,8 @@ batadv_hardif_add_interface(struct net_device *net_dev)
+ 	/* extra reference for return */
+ 	atomic_set(&hard_iface->refcount, 2);
+ 
++	atomic_set(&hard_iface->no_rebroadcast, 0);
++
+ 	batadv_check_known_mac_addr(hard_iface->net_dev);
+ 	list_add_tail_rcu(&hard_iface->list, &batadv_hardif_list);
+ 
+diff --git a/send.c b/send.c
+index d27161e..4383a66 100644
+--- a/send.c
++++ b/send.c
+@@ -513,6 +513,10 @@ static void batadv_send_outstanding_bcast_packet(struct work_struct *work)
+ 		if (forw_packet->num_packets >= hard_iface->num_bcasts)
+ 			continue;
+ 
++		if (atomic_read(&hard_iface->no_rebroadcast) &&
++		    forw_packet->skb->dev == hard_iface->net_dev)
++			continue;
++
+ 		/* send a copy of the saved skb */
+ 		skb1 = skb_clone(forw_packet->skb, GFP_ATOMIC);
+ 		if (skb1)
+diff --git a/sysfs-class-net-batman-adv b/sysfs-class-net-batman-adv
+index 7f34a95..cf7fe00 100644
+--- a/sysfs-class-net-batman-adv
++++ b/sysfs-class-net-batman-adv
+@@ -13,3 +13,13 @@ Description:
+                 displays the batman mesh interface this <iface>
+                 currently is associated with.
+ 
++What:           /sys/class/net/<iface>/batman-adv/no_rebroadcast
++Date:           Sep 2013
++Contact:        Linus Lüssing <linus.luessing@web.de>
++Description:
++                With this option set incoming multicast payload frames on
++                <iface> are not being rebroadcasted on <iface> again. This
++                option should be set on links which are known to be transitive
++                and symmetric only, for instance point-to-point wifi longshots
++                or wired links. Using this option wrongly is going to
++                break your mesh network, use at your own risk!
+diff --git a/sysfs.c b/sysfs.c
+index 1ebb0d9..780c52e 100644
+--- a/sysfs.c
++++ b/sysfs.c
+@@ -108,6 +108,17 @@ struct batadv_attribute batadv_attr_vlan_##_name = {	\
+ 	.store  = _store,				\
+ };
+ 
++/* Use this, if you have customized show and store functions
++ * for hard interface attrs
++ */
++#define BATADV_ATTR_HIF(_name, _mode, _show, _store)	\
++struct batadv_attribute batadv_attr_hif_##_name = {	\
++	.attr = {.name = __stringify(_name),		\
++		 .mode = _mode },			\
++	.show   = _show,				\
++	.store  = _store,				\
++};
++
+ /* Use this, if you have customized show and store functions */
+ #define BATADV_ATTR(_name, _mode, _show, _store)	\
+ struct batadv_attribute batadv_attr_##_name = {		\
+@@ -213,6 +224,52 @@ ssize_t batadv_show_vlan_##_name(struct kobject *kobj,			\
+ 	static BATADV_ATTR_VLAN(_name, _mode, batadv_show_vlan_##_name,	\
+ 				batadv_store_vlan_##_name)
+ 
++#define BATADV_ATTR_HIF_STORE_BOOL(_name, _post_func)			\
++ssize_t batadv_store_hif_##_name(struct kobject *kobj,			\
++				 struct attribute *attr, char *buff,	\
++				 size_t count)				\
++{									\
++	struct net_device *net_dev = batadv_kobj_to_netdev(kobj);	\
++	struct batadv_hard_iface *hard_iface;				\
++	size_t res;							\
++									\
++	hard_iface = batadv_hardif_get_by_netdev(net_dev);		\
++	if (!hard_iface)						\
++		return 0;						\
++									\
++	res = __batadv_store_bool_attr(buff, count, _post_func,		\
++					      attr, &hard_iface->_name,	\
++					      hard_iface->soft_iface);	\
++	batadv_hardif_free_ref(hard_iface);				\
++	return res;							\
++}
++
++#define BATADV_ATTR_HIF_SHOW_BOOL(_name)				\
++ssize_t batadv_show_hif_##_name(struct kobject *kobj,			\
++				struct attribute *attr, char *buff)	\
++{									\
++	struct net_device *net_dev = batadv_kobj_to_netdev(kobj);	\
++	struct batadv_hard_iface *hard_iface;				\
++	size_t res;							\
++									\
++	hard_iface = batadv_hardif_get_by_netdev(net_dev);		\
++	if (!hard_iface)						\
++		return 0;						\
++									\
++	res = sprintf(buff, "%s\n",					\
++		      atomic_read(&hard_iface->_name) == 0 ?		\
++				"disabled" : "enabled");		\
++	batadv_hardif_free_ref(hard_iface);				\
++	return res;							\
++}
++
++/* Use this, if you are going to turn a [name] in the vlan struct on or off */
++#define BATADV_ATTR_HIF_BOOL(_name, _mode, _post_func)			\
++	static BATADV_ATTR_HIF_STORE_BOOL(_name, _post_func)		\
++	static BATADV_ATTR_HIF_SHOW_BOOL(_name)				\
++	static BATADV_ATTR_HIF(_name, _mode, batadv_show_hif_##_name,	\
++			       batadv_store_hif_##_name)
++
+ static int batadv_store_bool_attr(char *buff, size_t count,
+ 				  struct net_device *net_dev,
+ 				  const char *attr_name, atomic_t *attr)
+@@ -834,10 +891,12 @@ static ssize_t batadv_show_iface_status(struct kobject *kobj,
+ static BATADV_ATTR(mesh_iface, S_IRUGO | S_IWUSR, batadv_show_mesh_iface,
+ 		   batadv_store_mesh_iface);
+ static BATADV_ATTR(iface_status, S_IRUGO, batadv_show_iface_status, NULL);
++BATADV_ATTR_HIF_BOOL(no_rebroadcast, S_IRUGO | S_IWUSR, NULL);
+ 
+ static struct batadv_attribute *batadv_batman_attrs[] = {
+ 	&batadv_attr_mesh_iface,
+ 	&batadv_attr_iface_status,
++	&batadv_attr_hif_no_rebroadcast,
+ 	NULL,
+ };
+ 
+diff --git a/types.h b/types.h
+index 8854c05..39619fb 100644
+--- a/types.h
++++ b/types.h
+@@ -101,6 +101,7 @@ struct batadv_hard_iface {
+ 	struct batadv_hard_iface_bat_iv bat_iv;
+ 	struct work_struct cleanup_work;
+ 	struct dentry *debug_dir;
++	atomic_t no_rebroadcast;
+ };
+ 
+ /**
+-- 
+2.1.0
+