#include <linux/if_vlan.h>
#include <linux/netdevice.h>
#include <net/net_namespace.h>
#include <net/netns/generic.h>

#undef pernet_operations

#if LINUX_VERSION_CODE <= KERNEL_VERSION(2,6,32)
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
static int net_assign_generic(struct net *net, int id, void *data);
#endif

static int __net_init compat_init_net(struct net *net, struct rpl_pernet_operations *pnet)
{
	int err;
	void *ovs_net = kzalloc(pnet->size, GFP_KERNEL);

	if (!ovs_net)
		return -ENOMEM;

	err = net_assign_generic(net, *pnet->id, ovs_net);
	if (err)
		goto err;

	if (pnet->init) {
		err = pnet->init(net);
		if (err)
			goto err;
	}

	return 0;
err:
	kfree(ovs_net);
	return err;
}

static void __net_exit compat_exit_net(struct net *net, struct rpl_pernet_operations *pnet)
{
	void *ovs_net = net_generic(net, *pnet->id);

	if (pnet->exit)
		pnet->exit(net);
	kfree(ovs_net);
}
#endif

#if LINUX_VERSION_CODE == KERNEL_VERSION(2,6,32)
#define DEFINE_PNET_REG_FUNC(PNET_TYPE)					\
	static struct rpl_pernet_operations *pnet_##PNET_TYPE;		\
static int __net_init compat_init_net_##PNET_TYPE(struct net *net)	\
{									\
	return compat_init_net(net, pnet_##PNET_TYPE);			\
}									\
									\
static void __net_exit compat_exit_net_##PNET_TYPE(struct net *net)	\
{									\
	compat_exit_net(net, pnet_##PNET_TYPE);				\
}									\
									\
static struct pernet_operations pnet_compat_##PNET_TYPE = {		\
	.init = compat_init_net_##PNET_TYPE,				\
	.exit = compat_exit_net_##PNET_TYPE,				\
};									\
									\
int rpl_register_pernet_##PNET_TYPE(struct rpl_pernet_operations *rpl_pnet)	\
{										\
	pnet_##PNET_TYPE = rpl_pnet;						\
	return register_pernet_##PNET_TYPE(pnet_##PNET_TYPE->id, &pnet_compat_##PNET_TYPE); \
}											\
											\
void rpl_unregister_pernet_##PNET_TYPE(struct rpl_pernet_operations *pnet)		\
{											\
	unregister_pernet_##PNET_TYPE(*pnet->id, &pnet_compat_##PNET_TYPE);		\
}

DEFINE_PNET_REG_FUNC(gen_device);

#elif LINUX_VERSION_CODE < KERNEL_VERSION(2,6,32)
#define MAX_DATA_COUNT 1
static struct net *net;

static void *__ovs_net_data[MAX_DATA_COUNT];
static int count;

static int net_assign_generic(struct net *net, int id, void *data)
{
	BUG_ON(id >= MAX_DATA_COUNT);
	__ovs_net_data[id] = data;
	return 0;
}

void *net_generic(const struct net *net, int id)
{
	return __ovs_net_data[id];
}

int rpl_register_pernet_gen_device(struct rpl_pernet_operations *rpl_pnet)
{
	*rpl_pnet->id = count++;
	return compat_init_net(net, rpl_pnet);
}

void rpl_unregister_pernet_gen_device(struct rpl_pernet_operations *rpl_pnet)
{
	compat_exit_net(net, rpl_pnet);
}

#endif