ipv6: Rename the dst_cache helper functions in ip6_tunnel

It is a prep work to fix the dst_entry refcnt bugs in
ip6_tunnel.

This patch rename:
1. ip6_tnl_dst_check() to ip6_tnl_dst_get() to better
   reflect that it will take a dst refcnt in the next patch.
2. ip6_tnl_dst_store() to ip6_tnl_dst_set() to have a more
   conventional name matching with ip6_tnl_dst_get().

Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: iamkafai

include/net/ip6_tunnel.h

@@ -60,9 +60,9 @@ struct ipv6_tlv_tnl_enc_lim {
 	__u8 encap_limit;	/* tunnel encapsulation limit   */
 } __packed;
 
-struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t);
+struct dst_entry *ip6_tnl_dst_get(struct ip6_tnl *t);
 void ip6_tnl_dst_reset(struct ip6_tnl *t);
-void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst);
+void ip6_tnl_dst_set(struct ip6_tnl *t, struct dst_entry *dst);
 int ip6_tnl_rcv_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,
 		const struct in6_addr *raddr);
 int ip6_tnl_xmit_ctl(struct ip6_tnl *t, const struct in6_addr *laddr,

net/ipv6/ip6_gre.c

@@ -634,7 +634,7 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 	}
 
 	if (!fl6->flowi6_mark)
-		dst = ip6_tnl_dst_check(tunnel);
+		dst = ip6_tnl_dst_get(tunnel);
 
 	if (!dst) {
 		ndst = ip6_route_output(net, NULL, fl6);
@@ -763,7 +763,7 @@ static netdev_tx_t ip6gre_xmit2(struct sk_buff *skb,
 
 	ip6tunnel_xmit(NULL, skb, dev);
 	if (ndst)
-		ip6_tnl_dst_store(tunnel, ndst);
+		ip6_tnl_dst_set(tunnel, ndst);
 	return 0;
 tx_err_link_failure:
 	stats->tx_carrier_errors++;

net/ipv6/ip6_tunnel.c

@@ -126,7 +126,7 @@ static struct net_device_stats *ip6_get_stats(struct net_device *dev)
  * Locking : hash tables are protected by RCU and RTNL
  */
 
-struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
+struct dst_entry *ip6_tnl_dst_get(struct ip6_tnl *t)
 {
 	struct dst_entry *dst = t->dst_cache;
 
@@ -139,7 +139,7 @@ struct dst_entry *ip6_tnl_dst_check(struct ip6_tnl *t)
 
 	return dst;
 }
-EXPORT_SYMBOL_GPL(ip6_tnl_dst_check);
+EXPORT_SYMBOL_GPL(ip6_tnl_dst_get);
 
 void ip6_tnl_dst_reset(struct ip6_tnl *t)
 {
@@ -148,14 +148,14 @@ void ip6_tnl_dst_reset(struct ip6_tnl *t)
 }
 EXPORT_SYMBOL_GPL(ip6_tnl_dst_reset);
 
-void ip6_tnl_dst_store(struct ip6_tnl *t, struct dst_entry *dst)
+void ip6_tnl_dst_set(struct ip6_tnl *t, struct dst_entry *dst)
 {
 	struct rt6_info *rt = (struct rt6_info *) dst;
 	t->dst_cookie = rt6_get_cookie(rt);
 	dst_release(t->dst_cache);
 	t->dst_cache = dst;
 }
-EXPORT_SYMBOL_GPL(ip6_tnl_dst_store);
+EXPORT_SYMBOL_GPL(ip6_tnl_dst_set);
 
 /**
  * ip6_tnl_lookup - fetch tunnel matching the end-point addresses
@@ -1010,7 +1010,7 @@ static int ip6_tnl_xmit2(struct sk_buff *skb,
 		memcpy(&fl6->daddr, addr6, sizeof(fl6->daddr));
 		neigh_release(neigh);
 	} else if (!fl6->flowi6_mark)
-		dst = ip6_tnl_dst_check(t);
+		dst = ip6_tnl_dst_get(t);
 
 	if (!ip6_tnl_xmit_ctl(t, &fl6->saddr, &fl6->daddr))
 		goto tx_err_link_failure;
@@ -1102,7 +1102,7 @@ static int ip6_tnl_xmit2(struct sk_buff *skb,
 	ipv6h->daddr = fl6->daddr;
 	ip6tunnel_xmit(NULL, skb, dev);
 	if (ndst)
-		ip6_tnl_dst_store(t, ndst);
+		ip6_tnl_dst_set(t, ndst);
 	return 0;
 tx_err_link_failure:
 	stats->tx_carrier_errors++;