Re: [PATCH net-next v2 09/12] vxlan: vni filtering support on collect metadata device

diff --git a/drivers/net/vxlan/vxlan_private.h b/drivers/net/vxlan/vxlan_private.h
index 7a946010a204..d697d6c51cb5 100644
--- a/drivers/net/vxlan/vxlan_private.h
+++ b/drivers/net/vxlan/vxlan_private.h

@@ -7,6 +7,8 @@
 #ifndef _VXLAN_PRIVATE_H
 #define _VXLAN_PRIVATE_H
 
+#include <linux/rhashtable.h>
+
 extern unsigned int vxlan_net_id;
 extern const u8 all_zeros_mac[ETH_ALEN + 2];
 

@@ -92,6 +94,38 @@ bool vxlan_addr_equal(const union vxlan_addr *a, const union vxlan_addr *b)
 
 #endif
 
+static inline int vxlan_vni_cmp(struct rhashtable_compare_arg *arg,
+				const void *ptr)
+{
+	const struct vxlan_vni_node *vnode = ptr;
+	__be32 vni = *(__be32 *)arg->key;
+
+	return vnode->vni != vni;
+}

+static const struct rhashtable_params vxlan_vni_rht_params = {
+	.head_offset = offsetof(struct vxlan_vni_node, vnode),
+	.key_offset = offsetof(struct vxlan_vni_node, vni),
+	.key_len = sizeof(__be32),
+	.nelem_hint = 3,
+	.max_size = VXLAN_N_VID,
+	.obj_cmpfn = vxlan_vni_cmp,
+	.automatic_shrinking = true,
+};

+static inline struct vxlan_vni_node *
+vxlan_vnifilter_lookup(struct vxlan_dev *vxlan, __be32 vni)
+{
+	struct vxlan_vni_group *vg;
+
+	vg = rcu_dereference_rtnl(vxlan->vnigrp);
+	if (!vg)
+		return NULL;
+
+	return rhashtable_lookup_fast(&vg->vni_hash, &vni,
+				      vxlan_vni_rht_params);
+}