C++ (Cpp) ip_tunnel_dst_cache_usable Examples

Example #1

File: ip_gre.c Project: acton393/linux

static void gre_fb_xmit(struct sk_buff *skb, struct net_device *dev,
			__be16 proto)
{
	struct ip_tunnel_info *tun_info;
	const struct ip_tunnel_key *key;
	struct rtable *rt = NULL;
	struct flowi4 fl;
	int min_headroom;
	int tunnel_hlen;
	__be16 df, flags;
	bool use_cache;
	int err;

	tun_info = skb_tunnel_info(skb);
	if (unlikely(!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX) ||
		     ip_tunnel_info_af(tun_info) != AF_INET))
		goto err_free_skb;

	key = &tun_info->key;
	use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);
	if (use_cache)
		rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl.saddr);
	if (!rt) {
		rt = gre_get_rt(skb, dev, &fl, key);
		if (IS_ERR(rt))
				goto err_free_skb;
		if (use_cache)
			dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
					  fl.saddr);
	}

	tunnel_hlen = gre_calc_hlen(key->tun_flags);

	min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
			+ tunnel_hlen + sizeof(struct iphdr);
	if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) {
		int head_delta = SKB_DATA_ALIGN(min_headroom -
						skb_headroom(skb) +
						16);
		err = pskb_expand_head(skb, max_t(int, head_delta, 0),
				       0, GFP_ATOMIC);
		if (unlikely(err))
			goto err_free_rt;
	}

Example #2

File: ip_gre.c Project: openvswitch/ovs

static struct rtable *prepare_fb_xmit(struct sk_buff *skb,
				      struct net_device *dev,
				      struct flowi4 *fl,
				      int tunnel_hlen)
{
	struct ip_tunnel_info *tun_info;
	const struct ip_tunnel_key *key;
	struct rtable *rt = NULL;
	int min_headroom;
	bool use_cache;
	int err;

	tun_info = skb_tunnel_info(skb);
	key = &tun_info->key;
	use_cache = ip_tunnel_dst_cache_usable(skb, tun_info);

	if (use_cache)
		rt = dst_cache_get_ip4(&tun_info->dst_cache, &fl->saddr);
	if (!rt) {
		rt = gre_get_rt(skb, dev, fl, key);
		if (IS_ERR(rt))
			goto err_free_skb;
		if (use_cache)
			dst_cache_set_ip4(&tun_info->dst_cache, &rt->dst,
					  fl->saddr);
	}

	min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
			+ tunnel_hlen + sizeof(struct iphdr);
	if (skb_headroom(skb) < min_headroom || skb_header_cloned(skb)) {
		int head_delta = SKB_DATA_ALIGN(min_headroom -
						skb_headroom(skb) +
						16);
		err = pskb_expand_head(skb, max_t(int, head_delta, 0),
				       0, GFP_ATOMIC);
		if (unlikely(err))
			goto err_free_rt;
	}