batman-adv: add sysfs framework for VLAN

Each VLAN can now have its own set of attributes which are
exported through a new subfolder in the sysfs tree.
Each VLAN created on top of a soft_iface will have its own
subfolder.

The subfolder is named "vlan%VID" and it is created inside
the "mesh" sysfs folder belonging to batman-adv.

Attributes corresponding to the untagged LAN are stored in
the root sysfs folder as before.

This patch also creates all the needed macros and data
structures to easily handle new VLAN spacific attributes.

Signed-off-by: Antonio Quartulli <antonio@open-mesh.com>
Signed-off-by: Marek Lindner <lindner_marek@yahoo.de>
diff --git a/net/batman-adv/sysfs.h b/net/batman-adv/sysfs.h
index 479acf4..c7d725d 100644
--- a/net/batman-adv/sysfs.h
+++ b/net/batman-adv/sysfs.h
@@ -22,6 +22,12 @@
 
 #define BATADV_SYSFS_IF_MESH_SUBDIR "mesh"
 #define BATADV_SYSFS_IF_BAT_SUBDIR "batman_adv"
+/**
+ * BATADV_SYSFS_VLAN_SUBDIR_PREFIX - prefix of the subfolder that will be
+ *  created in the sysfs hierarchy for each VLAN interface. The subfolder will
+ *  be named "BATADV_SYSFS_VLAN_SUBDIR_PREFIX%vid".
+ */
+#define BATADV_SYSFS_VLAN_SUBDIR_PREFIX "vlan"
 
 struct batadv_attribute {
 	struct attribute attr;
@@ -36,6 +42,10 @@
 int batadv_sysfs_add_hardif(struct kobject **hardif_obj,
 			    struct net_device *dev);
 void batadv_sysfs_del_hardif(struct kobject **hardif_obj);
+int batadv_sysfs_add_vlan(struct net_device *dev,
+			  struct batadv_softif_vlan *vlan);
+void batadv_sysfs_del_vlan(struct batadv_priv *bat_priv,
+			   struct batadv_softif_vlan *vlan);
 int batadv_throw_uevent(struct batadv_priv *bat_priv, enum batadv_uev_type type,
 			enum batadv_uev_action action, const char *data);