batman-adv: Deinline batadv_orig_hash_find, save 7339 bytes

This function compiles to 288 bytes of machine code for Linux 4.14 on
Debian Stretch amd64 and (6.3.0-18) with the default configuration. 27
callsites (25 used in default config).

   text    data     bss     dec     hex filename
 179291   10317    4416  194024   2f5e8 batman-adv.ko.pre
 171952   10317    4416  186685   2d93d batman-adv.ko.post

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
[sven@narfation.org: Fix includes, correct sizes+counts in commit message]
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
diff --git a/net/batman-adv/originator.c b/net/batman-adv/originator.c
index 2967b86..0a565d0 100644
--- a/net/batman-adv/originator.c
+++ b/net/batman-adv/originator.c
@@ -30,10 +30,12 @@
 #include <linux/netdevice.h>
 #include <linux/netlink.h>
 #include <linux/rculist.h>
+#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/workqueue.h>
 #include <net/sock.h>
 #include <uapi/linux/batman_adv.h>
@@ -55,6 +57,36 @@
 /* hash class keys */
 static struct lock_class_key batadv_orig_hash_lock_class_key;
 
+struct batadv_orig_node *
+batadv_orig_hash_find(struct batadv_priv *bat_priv, const void *data)
+{
+	struct batadv_hashtable *hash = bat_priv->orig_hash;
+	struct hlist_head *head;
+	struct batadv_orig_node *orig_node, *orig_node_tmp = NULL;
+	int index;
+
+	if (!hash)
+		return NULL;
+
+	index = batadv_choose_orig(data, hash->size);
+	head = &hash->table[index];
+
+	rcu_read_lock();
+	hlist_for_each_entry_rcu(orig_node, head, hash_entry) {
+		if (!batadv_compare_eth(orig_node, data))
+			continue;
+
+		if (!kref_get_unless_zero(&orig_node->refcount))
+			continue;
+
+		orig_node_tmp = orig_node;
+		break;
+	}
+	rcu_read_unlock();
+
+	return orig_node_tmp;
+}
+
 static void batadv_purge_orig(struct work_struct *work);
 
 /**