#ifndef __NET_IPIP_H#define __NET_IPIP_H 1 #include <linux/if_tunnel.h>#include <net/gro_cells.h>#include <net/ip.h> /* Keep error state on tunnel for 30 sec */#define IPTUNNEL_ERR_TIMEO	(30*HZ) /* 6rd prefix/relay information */struct ip_tunnel_6rd_parm {	struct in6_addr		prefix;	__be32			relay_prefix;	u16			prefixlen;	u16			relay_prefixlen;}; struct ip_tunnel {	struct ip_tunnel __rcu	*next;	struct net_device	*dev; 	int			err_count;	/* Number of arrived ICMP errors */	unsigned long		err_time;	/* Time when the last ICMP error arrived */ 	/* These four fields used only by GRE */	__u32			i_seqno;	/* The last seen seqno	*/	__u32			o_seqno;	/* The last output seqno */	int			hlen;		/* Precalculated GRE header length */	int			mlink; 	struct ip_tunnel_parm	parms; 	/* for SIT */#ifdef CONFIG_IPV6_SIT_6RD	struct ip_tunnel_6rd_parm	ip6rd;#endif	struct ip_tunnel_prl_entry __rcu *prl;		/* potential router list */	unsigned int			prl_count;	/* # of entries in PRL */ 	struct gro_cells		gro_cells;}; struct ip_tunnel_prl_entry {	struct ip_tunnel_prl_entry __rcu *next;	__be32				addr;	u16				flags;	struct rcu_head			rcu_head;}; static inline void iptunnel_xmit(struct sk_buff *skb, struct net_device *dev){	int err;	struct iphdr *iph = ip_hdr(skb);	int pkt_len = skb->len - skb_transport_offset(skb);	struct pcpu_tstats *tstats = this_cpu_ptr(dev->tstats); 	nf_reset(skb);	skb->ip_summed = CHECKSUM_NONE;	ip_select_ident(iph, skb_dst(skb), NULL); 	err = ip_local_out(skb);	if (likely(net_xmit_eval(err) == 0)) {		u64_stats_update_begin(&tstats->syncp);		tstats->tx_bytes += pkt_len;		tstats->tx_packets++;		u64_stats_update_end(&tstats->syncp);	} else {		dev->stats.tx_errors++;		dev->stats.tx_aborted_errors++;	}} #endif