batman-adv: Make sysfs support optional

The sysfs files will be marked as deprecated in the near future. They are
already replaced by the batadv generic netlink family. Add an Kconfig
option to disable the sysfs support for users who want to test their tools
or want to safe some space. This setting should currently still be enabled
by default to keep backward compatible with legacy tools.
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>

net/batman-adv/Kconfig

@@ -97,6 +97,18 @@ config BATMAN_ADV_DEBUG
 	  buffer. The output is controlled via the batadv netdev specific
 	  log_level setting.
 
+config BATMAN_ADV_SYSFS
+	bool "batman-adv sysfs entries"
+	depends on BATMAN_ADV
+	default y
+	help
+	  Say Y here if you want to enable batman-adv device configuration and
+	  status interface through sysfs attributes. It is replaced by the
+	  batadv generic netlink family but still used by various userspace
+	  tools and scripts.
+
+	  If unsure, say Y.
+
 config BATMAN_ADV_TRACING
 	bool "B.A.T.M.A.N. tracing support"
 	depends on BATMAN_ADV

net/batman-adv/Makefile

@@ -28,7 +28,7 @@ batman-adv-y += originator.o
 batman-adv-y += routing.o
 batman-adv-y += send.o
 batman-adv-y += soft-interface.o
-batman-adv-y += sysfs.o
+batman-adv-$(CONFIG_BATMAN_ADV_SYSFS) += sysfs.o
 batman-adv-$(CONFIG_BATMAN_ADV_TRACING) += trace.o
 batman-adv-y += tp_meter.o
 batman-adv-y += translation-table.o

net/batman-adv/bridge_loop_avoidance.c

@@ -47,7 +47,6 @@
 #include "netlink.h"
 #include "originator.h"
 #include "soft-interface.h"
-#include "sysfs.h"
 #include "translation-table.h"
 
 static const u8 batadv_announce_mac[4] = {0x43, 0x05, 0x43, 0x05};

net/batman-adv/gateway_client.c

@@ -41,7 +41,6 @@
 #include "originator.h"
 #include "routing.h"
 #include "soft-interface.h"
-#include "sysfs.h"
 #include "translation-table.h"
 
 /* These are the offsets of the "hw type" and "hw address length" in the dhcp

net/batman-adv/main.c

@@ -10,6 +10,7 @@
 #include <linux/build_bug.h>
 #include <linux/byteorder/generic.h>
 #include <linux/crc32c.h>
+#include <linux/device.h>
 #include <linux/errno.h>
 #include <linux/genetlink.h>
 #include <linux/gfp.h>
@@ -19,6 +20,7 @@
 #include <linux/ip.h>
 #include <linux/ipv6.h>
 #include <linux/kernel.h>
+#include <linux/kobject.h>
 #include <linux/kref.h>
 #include <linux/list.h>
 #include <linux/module.h>
@@ -28,6 +30,7 @@
 #include <linux/rcupdate.h>
 #include <linux/seq_file.h>
 #include <linux/skbuff.h>
+#include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/stddef.h>
 #include <linux/string.h>
@@ -72,6 +75,22 @@ struct workqueue_struct *batadv_event_workqueue;
 
 static void batadv_recv_handler_init(void);
 
+#define BATADV_UEV_TYPE_VAR	"BATTYPE="
+#define BATADV_UEV_ACTION_VAR	"BATACTION="
+#define BATADV_UEV_DATA_VAR	"BATDATA="
+
+static char *batadv_uev_action_str[] = {
+	"add",
+	"del",
+	"change",
+	"loopdetect",
+};
+
+static char *batadv_uev_type_str[] = {
+	"gw",
+	"bla",
+};
+
 static int __init batadv_init(void)
 {
 	int ret;
@@ -666,6 +685,60 @@ bool batadv_vlan_ap_isola_get(struct batadv_priv *bat_priv, unsigned short vid)
 	return ap_isolation_enabled;
 }
 
+/**
+ * batadv_throw_uevent() - Send an uevent with batman-adv specific env data
+ * @bat_priv: the bat priv with all the soft interface information
+ * @type: subsystem type of event. Stored in uevent's BATTYPE
+ * @action: action type of event. Stored in uevent's BATACTION
+ * @data: string with additional information to the event (ignored for
+ *  BATADV_UEV_DEL). Stored in uevent's BATDATA
+ *
+ * Return: 0 on success or negative error number in case of failure
+ */
+int batadv_throw_uevent(struct batadv_priv *bat_priv, enum batadv_uev_type type,
+			enum batadv_uev_action action, const char *data)
+{
+	int ret = -ENOMEM;
+	struct kobject *bat_kobj;
+	char *uevent_env[4] = { NULL, NULL, NULL, NULL };
+
+	bat_kobj = &bat_priv->soft_iface->dev.kobj;
+
+	uevent_env[0] = kasprintf(GFP_ATOMIC,
+				  "%s%s", BATADV_UEV_TYPE_VAR,
+				  batadv_uev_type_str[type]);
+	if (!uevent_env[0])
+		goto out;
+
+	uevent_env[1] = kasprintf(GFP_ATOMIC,
+				  "%s%s", BATADV_UEV_ACTION_VAR,
+				  batadv_uev_action_str[action]);
+	if (!uevent_env[1])
+		goto out;
+
+	/* If the event is DEL, ignore the data field */
+	if (action != BATADV_UEV_DEL) {
+		uevent_env[2] = kasprintf(GFP_ATOMIC,
+					  "%s%s", BATADV_UEV_DATA_VAR, data);
+		if (!uevent_env[2])
+			goto out;
+	}
+
+	ret = kobject_uevent_env(bat_kobj, KOBJ_CHANGE, uevent_env);
+out:
+	kfree(uevent_env[0]);
+	kfree(uevent_env[1]);
+	kfree(uevent_env[2]);
+
+	if (ret)
+		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
+			   "Impossible to send uevent for (%s,%s,%s) event (err: %d)\n",
+			   batadv_uev_type_str[type],
+			   batadv_uev_action_str[action],
+			   (action == BATADV_UEV_DEL ? "NULL" : data), ret);
+	return ret;
+}
+
 module_init(batadv_init);
 module_exit(batadv_exit);
 

net/batman-adv/main.h

@@ -382,5 +382,7 @@ static inline void batadv_add_counter(struct batadv_priv *bat_priv, size_t idx,
 
 unsigned short batadv_get_vid(struct sk_buff *skb, size_t header_len);
 bool batadv_vlan_ap_isola_get(struct batadv_priv *bat_priv, unsigned short vid);
+int batadv_throw_uevent(struct batadv_priv *bat_priv, enum batadv_uev_type type,
+			enum batadv_uev_action action, const char *data);
 
 #endif /* _NET_BATMAN_ADV_MAIN_H_ */

net/batman-adv/sysfs.c

@@ -102,22 +102,6 @@ batadv_kobj_to_vlan(struct batadv_priv *bat_priv, struct kobject *obj)
 	return vlan;
 }
 
-#define BATADV_UEV_TYPE_VAR	"BATTYPE="
-#define BATADV_UEV_ACTION_VAR	"BATACTION="
-#define BATADV_UEV_DATA_VAR	"BATDATA="
-
-static char *batadv_uev_action_str[] = {
-	"add",
-	"del",
-	"change",
-	"loopdetect",
-};
-
-static char *batadv_uev_type_str[] = {
-	"gw",
-	"bla",
-};
-
 /* Use this, if you have customized show and store functions for vlan attrs */
 #define BATADV_ATTR_VLAN(_name, _mode, _show, _store)	\
 struct batadv_attribute batadv_attr_vlan_##_name = {	\
@@ -1235,57 +1219,3 @@ void batadv_sysfs_del_hardif(struct kobject **hardif_obj)
 	kobject_put(*hardif_obj);
 	*hardif_obj = NULL;
 }
-
-/**
- * batadv_throw_uevent() - Send an uevent with batman-adv specific env data
- * @bat_priv: the bat priv with all the soft interface information
- * @type: subsystem type of event. Stored in uevent's BATTYPE
- * @action: action type of event. Stored in uevent's BATACTION
- * @data: string with additional information to the event (ignored for
- *  BATADV_UEV_DEL). Stored in uevent's BATDATA
- *
- * Return: 0 on success or negative error number in case of failure
- */
-int batadv_throw_uevent(struct batadv_priv *bat_priv, enum batadv_uev_type type,
-			enum batadv_uev_action action, const char *data)
-{
-	int ret = -ENOMEM;
-	struct kobject *bat_kobj;
-	char *uevent_env[4] = { NULL, NULL, NULL, NULL };
-
-	bat_kobj = &bat_priv->soft_iface->dev.kobj;
-
-	uevent_env[0] = kasprintf(GFP_ATOMIC,
-				  "%s%s", BATADV_UEV_TYPE_VAR,
-				  batadv_uev_type_str[type]);
-	if (!uevent_env[0])
-		goto out;
-
-	uevent_env[1] = kasprintf(GFP_ATOMIC,
-				  "%s%s", BATADV_UEV_ACTION_VAR,
-				  batadv_uev_action_str[action]);
-	if (!uevent_env[1])
-		goto out;
-
-	/* If the event is DEL, ignore the data field */
-	if (action != BATADV_UEV_DEL) {
-		uevent_env[2] = kasprintf(GFP_ATOMIC,
-					  "%s%s", BATADV_UEV_DATA_VAR, data);
-		if (!uevent_env[2])
-			goto out;
-	}
-
-	ret = kobject_uevent_env(bat_kobj, KOBJ_CHANGE, uevent_env);
-out:
-	kfree(uevent_env[0]);
-	kfree(uevent_env[1]);
-	kfree(uevent_env[2]);
-
-	if (ret)
-		batadv_dbg(BATADV_DBG_BATMAN, bat_priv,
-			   "Impossible to send uevent for (%s,%s,%s) event (err: %d)\n",
-			   batadv_uev_type_str[type],
-			   batadv_uev_action_str[action],
-			   (action == BATADV_UEV_DEL ? "NULL" : data), ret);
-	return ret;
-}

net/batman-adv/sysfs.h

@@ -45,6 +45,8 @@ struct batadv_attribute {
 			 char *buf, size_t count);
 };
 
+#ifdef CONFIG_BATMAN_ADV_SYSFS
+
 int batadv_sysfs_add_meshif(struct net_device *dev);
 void batadv_sysfs_del_meshif(struct net_device *dev);
 int batadv_sysfs_add_hardif(struct kobject **hardif_obj,
@@ -54,7 +56,39 @@ 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);
+
+#else
+
+static inline int batadv_sysfs_add_meshif(struct net_device *dev)
+{
+	return 0;
+}
+
+static inline void batadv_sysfs_del_meshif(struct net_device *dev)
+{
+}
+
+static inline int batadv_sysfs_add_hardif(struct kobject **hardif_obj,
+					  struct net_device *dev)
+{
+	return 0;
+}
+
+static inline void batadv_sysfs_del_hardif(struct kobject **hardif_obj)
+{
+}
+
+static inline int batadv_sysfs_add_vlan(struct net_device *dev,
+					struct batadv_softif_vlan *vlan)
+{
+	return 0;
+}
+
+static inline void batadv_sysfs_del_vlan(struct batadv_priv *bat_priv,
+					 struct batadv_softif_vlan *vlan)
+{
+}
+
+#endif
 
 #endif /* _NET_BATMAN_ADV_SYSFS_H_ */