linux/net/bridge/br_vlan_tunnel.c

/*
 *	Bridge per vlan tunnel port dst_metadata handling code
 *
 *	Authors:
 *	Roopa Prabhu		<roopa@cumulusnetworks.com>
 *
 *	This program is free software; you can redistribute it and/or
 *	modify it under the terms of the GNU General Public License
 *	as published by the Free Software Foundation; either version
 *	2 of the License, or (at your option) any later version.
 */

#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>
#include <net/switchdev.h>
#include <net/dst_metadata.h>

#include "br_private.h"
#include "br_private_tunnel.h"

static inline int br_vlan_tunid_cmp(struct rhashtable_compare_arg *arg,
				    const void *ptr)
{
	const struct net_bridge_vlan *vle = ptr;
	__be64 tunid = *(__be64 *)arg->key;

	return vle->tinfo.tunnel_id != tunid;
}

static const struct rhashtable_params br_vlan_tunnel_rht_params = {
	.head_offset = offsetof(struct net_bridge_vlan, tnode),
	.key_offset = offsetof(struct net_bridge_vlan, tinfo.tunnel_id),
	.key_len = sizeof(__be64),
	.nelem_hint = 3,
	.locks_mul = 1,
	.obj_cmpfn = br_vlan_tunid_cmp,
	.automatic_shrinking = true,
};

void vlan_tunnel_info_del(struct net_bridge_vlan_group *vg,
			  struct net_bridge_vlan *vlan)
{
	if (!vlan->tinfo.tunnel_dst)
		return;
	rhashtable_remove_fast(&vg->tunnel_hash, &vlan->tnode,
			       br_vlan_tunnel_rht_params);
	vlan->tinfo.tunnel_id = 0;
	dst_release(&vlan->tinfo.tunnel_dst->dst);
	vlan->tinfo.tunnel_dst = NULL;
}

static int __vlan_tunnel_info_add(struct net_bridge_vlan_group *vg,
				  struct net_bridge_vlan *vlan, u32 tun_id)
{
	struct metadata_dst *metadata = NULL;
	__be64 key = key32_to_tunnel_id(cpu_to_be32(tun_id));
	int err;

	if (vlan->tinfo.tunnel_dst)
		return -EEXIST;

	metadata = __ip_tun_set_dst(0, 0, 0, 0, 0, TUNNEL_KEY,
				    key, 0);
	if (!metadata)
		return -EINVAL;

	metadata->u.tun_info.mode |= IP_TUNNEL_INFO_TX | IP_TUNNEL_INFO_BRIDGE;
	vlan->tinfo.tunnel_dst = metadata;
	vlan->tinfo.tunnel_id = key;

	err = rhashtable_lookup_insert_fast(&vg->tunnel_hash, &vlan->tnode,
					    br_vlan_tunnel_rht_params);
	if (err)
		goto out;

	return 0;
out:
	dst_release(&vlan->tinfo.tunnel_dst->dst);

	return err;
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int nbp_vlan_tunnel_info_add(struct net_bridge_port *port, u16 vid, u32 tun_id)
{
	struct net_bridge_vlan_group *vg;
	struct net_bridge_vlan *vlan;

	ASSERT_RTNL();

	vg = nbp_vlan_group(port);
	vlan = br_vlan_find(vg, vid);
	if (!vlan)
		return -EINVAL;

	return __vlan_tunnel_info_add(vg, vlan, tun_id);
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int nbp_vlan_tunnel_info_delete(struct net_bridge_port *port, u16 vid)
{
	struct net_bridge_vlan_group *vg;
	struct net_bridge_vlan *v;

	ASSERT_RTNL();

	vg = nbp_vlan_group(port);
	v = br_vlan_find(vg, vid);
	if (!v)
		return -ENOENT;

	vlan_tunnel_info_del(vg, v);

	return 0;
}

static void __vlan_tunnel_info_flush(struct net_bridge_vlan_group *vg)
{
	struct net_bridge_vlan *vlan, *tmp;

	list_for_each_entry_safe(vlan, tmp, &vg->vlan_list, vlist)
		vlan_tunnel_info_del(vg, vlan);
}

void nbp_vlan_tunnel_info_flush(struct net_bridge_port *port)
{
	struct net_bridge_vlan_group *vg;

	ASSERT_RTNL();

	vg = nbp_vlan_group(port);
	__vlan_tunnel_info_flush(vg);
}

int vlan_tunnel_init(struct net_bridge_vlan_group *vg)
{
	return rhashtable_init(&vg->tunnel_hash, &br_vlan_tunnel_rht_params);
}

void vlan_tunnel_deinit(struct net_bridge_vlan_group *vg)
{
	rhashtable_destroy(&vg->tunnel_hash);
}