path: root/drivers/net/ipvlan/ipvlan_main.c

/* Copyright (c) 2014 Mahesh Bandewar <maheshb@google.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 "ipvlan.h"

static unsigned int ipvlan_netid __read_mostly;

struct ipvlan_netns {
	unsigned int ipvl_nf_hook_refcnt;
};

static const struct nf_hook_ops ipvl_nfops[] = {
	{
		.hook     = ipvlan_nf_input,
		.pf       = NFPROTO_IPV4,
		.hooknum  = NF_INET_LOCAL_IN,
		.priority = INT_MAX,
	},
	{
		.hook     = ipvlan_nf_input,
		.pf       = NFPROTO_IPV6,
		.hooknum  = NF_INET_LOCAL_IN,
		.priority = INT_MAX,
	},
};

static const struct l3mdev_ops ipvl_l3mdev_ops = {
	.l3mdev_l3_rcv = ipvlan_l3_rcv,
};

static void ipvlan_adjust_mtu(struct ipvl_dev *ipvlan, struct net_device *dev)
{
	ipvlan->dev->mtu = dev->mtu;
}

static int ipvlan_register_nf_hook(struct net *net)
{
	struct ipvlan_netns *vnet = net_generic(net, ipvlan_netid);
	int err = 0;

	if (!vnet->ipvl_nf_hook_refcnt) {
		err = nf_register_net_hooks(net, ipvl_nfops,
					    ARRAY_SIZE(ipvl_nfops));
		if (!err)
			vnet->ipvl_nf_hook_refcnt = 1;
	} else {
		vnet->ipvl_nf_hook_refcnt++;
	}

	return err;
}

static void ipvlan_unregister_nf_hook(struct net *net)
{
	struct ipvlan_netns *vnet = net_generic(net, ipvlan_netid);

	if (WARN_ON(!vnet->ipvl_nf_hook_refcnt))
		return;

	vnet->ipvl_nf_hook_refcnt--;
	if (!vnet->ipvl_nf_hook_refcnt)
		nf_unregister_net_hooks(net, ipvl_nfops,
					ARRAY_SIZE(ipvl_nfops));
}

static int ipvlan_set_port_mode(struct ipvl_port *port, u16 nval)
{
	struct ipvl_dev *ipvlan;
	struct net_device *mdev = port->dev;
	int err = 0;

	ASSERT_RTNL();
	if (port->mode != nval) {
		if (nval == IPVLAN_MODE_L3S) {
			/* New mode is L3S */
			err = ipvlan_register_nf_hook(read_pnet(&port->pnet));
			if (!err) {
				mdev->l3mdev_ops = &ipvl_l3mdev_ops;
				mdev->priv_flags |= IFF_L3MDEV_MASTER;
			} else
				return err;
		} else if (port->mode == IPVLAN_MODE_L3S) {
			/* Old mode was L3S */
			mdev->priv_flags &= ~IFF_L3MDEV_MASTER;
			ipvlan_unregister_nf_hook(read_pnet(&port->pnet));
			mdev->l3mdev_ops = NULL;
		}
		list_for_each_entry(ipvlan, &port->ipvlans, pnode) {
			if (nval == IPVLAN_MODE_L3 || nval == IPVLAN_MODE_L3S)
				ipvlan->dev->flags |= IFF_NOARP;
			else
				ipvlan->dev->flags &= ~IFF_NOARP;
		}
		port->mode = nval;
	}
	return err;
}

static int ipvlan_port_create(struct net_device *dev)
{
	struct ipvl_port *port;
	int err, idx;

	port = kzalloc(sizeof(struct ipvl_port), GFP_KERNEL);
	if (!port)
		return -ENOMEM;

	write_pnet(&port->pnet, dev_net(dev));
	port->dev = dev;
	port->mode = IPVLAN_MODE_L3;
	INIT_LIST_HEAD(&port->ipvlans);
	for (idx = 0; idx < IPVLAN_HASH_SIZE; idx++)
		INIT_HLIST_HEAD(&port->hlhead[idx]);

	skb_queue_head_init(&port->backlog);
	INIT_WORK(&port->wq, ipvlan_process_multicast);
	ida_init(&port->ida);
	port->dev_id_start = 1;

	err = netdev_rx_handler_register(dev, ipvlan_handle_frame, port);
	if (err)
		goto err;

	dev->priv_flags |= IFF_IPVLAN_MASTER;
	return 0;

err:
	kfree(port);
	return err;
}

static void ipvlan_port_destroy(struct net_device *dev)
{
	struct ipvl_port *port = ipvlan_port_get_rtnl(dev);
	struct sk_buff *skb;

	dev->priv_flags &= ~IFF_IPVLAN_MASTER;
	if (port->mode == IPVLAN_MODE_L3S) {
		dev->priv_flags &= ~IFF_L3MDEV_MASTER;
		ipvlan_unregister_nf_hook(dev_net(dev));
		dev->l3mdev_ops = NULL;
	}
	netdev_rx_handler_unregister(dev);
	cancel_work_sync(&port->wq);
	while ((skb = __skb_dequeue(&port->backlog)) != NULL) {
		if (skb->dev)
			dev_put(skb->dev);
		kfree_skb(skb);
	}
	ida_destroy(&port->ida);
	kfree(port);
}

#define IPVLAN_FEATURES \
	(NETIF_F_SG | NETIF_F_HW_CSUM | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST | \