[PATCH net-next] ip_tunnel: Add dst_cache management lwtunnel_state of ip tunnel

[wenxu@ucloud.cn]

From: wenxu <wenxu@ucloud.cn>

The lwtunnel_state is not init the dst_cache Which make the
ip_md_tunnel_xmit can't use the dst_cache. It will lookup
route table every packets.

Signed-off-by: wenxu <wenxu@ucloud.cn>
---
 net/ipv4/ip_tunnel_core.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/net/ipv4/ip_tunnel_core.c b/net/ipv4/ip_tunnel_core.c
index 9a0e67b..6168b90 100644
--- a/net/ipv4/ip_tunnel_core.c
+++ b/net/ipv4/ip_tunnel_core.c
@@ -252,6 +252,12 @@ static int ip_tun_build_state(struct nlattr *attr,
 
 	tun_info = lwt_tun_info(new_state);
 
+	err = dst_cache_init(&tun_info->dst_cache, GFP_ATOMIC);
+	if (err) {
+		lwtstate_free(new_state);
+		return err;
+	}
+
 	if (tb[LWTUNNEL_IP_ID])
 		tun_info->key.tun_id = nla_get_be64(tb[LWTUNNEL_IP_ID]);
 
@@ -278,6 +284,13 @@ static int ip_tun_build_state(struct nlattr *attr,
 	return 0;
 }
 
+static int ip_tun_destroy_state(struct lwtunnel_state *lwtstate)
+{
+	struct ip_tunnel_info *tun_info = lwt_tun_info(lwtstate);
+
+	dst_cache_destroy(&tun_info->dst_cache);
+}
+
 static int ip_tun_fill_encap_info(struct sk_buff *skb,
 				  struct lwtunnel_state *lwtstate)
 {
@@ -313,6 +326,7 @@ static int ip_tun_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b)
 
 static const struct lwtunnel_encap_ops ip_tun_lwt_ops = {
 	.build_state = ip_tun_build_state,
+	.destroy_state = ip_tun_destroy_state,
 	.fill_encap = ip_tun_fill_encap_info,
 	.get_encap_size = ip_tun_encap_nlsize,
 	.cmp_encap = ip_tun_cmp_encap,
-- 
1.8.3.1