net: skb->dst accessors

Define three accessors to get/set dst attached to a skb

struct dst_entry *skb_dst(const struct sk_buff *skb)

void skb_dst_set(struct sk_buff *skb, struct dst_entry *dst)

void skb_dst_drop(struct sk_buff *skb)
This one should replace occurrences of :
dst_release(skb->dst)
skb->dst = NULL;

Delete skb->dst field

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 11 insertions, 12 deletions

diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c
index 85ddad45a918..44e2a3d2359a 100644
--- a/net/ipv4/ip_gre.c
+++ b/net/ipv4/ip_gre.c
@@ -643,8 +643,7 @@ static int ipgre_rcv(struct sk_buff *skb)
                 stats->rx_packets++;
                 stats->rx_bytes += len;
                 skb->dev = tunnel->dev;
-                dst_release(skb->dst);
-                skb->dst = NULL;
+                skb_dst_drop(skb);
                 nf_reset(skb);
 
                 skb_reset_network_header(skb);
@@ -698,7 +697,7 @@ static int ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
         if ((dst = tiph->daddr) == 0) {
                 /* NBMA tunnel */
 
-                if (skb->dst == NULL) {
+                if (skb_dst(skb) == NULL) {
                         stats->tx_fifo_errors++;
                         goto tx_error;
                 }
@@ -712,7 +711,7 @@ static int ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
                 else if (skb->protocol == htons(ETH_P_IPV6)) {
                         struct in6_addr *addr6;
                         int addr_type;
-                        struct neighbour *neigh = skb->dst->neighbour;
+                        struct neighbour *neigh = skb_dst(skb)->neighbour;
 
                         if (neigh == NULL)
                                 goto tx_error;
@@ -766,10 +765,10 @@ static int ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
         if (df)
                 mtu = dst_mtu(&rt->u.dst) - dev->hard_header_len - tunnel->hlen;
         else
-                mtu = skb->dst ? dst_mtu(skb->dst) : dev->mtu;
+                mtu = skb_dst(skb) ? dst_mtu(skb_dst(skb)) : dev->mtu;
 
-        if (skb->dst)
-                skb->dst->ops->update_pmtu(skb->dst, mtu);
+        if (skb_dst(skb))
+                skb_dst(skb)->ops->update_pmtu(skb_dst(skb), mtu);
 
         if (skb->protocol == htons(ETH_P_IP)) {
                 df |= (old_iph->frag_off&htons(IP_DF));
@@ -783,14 +782,14 @@ static int ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
         }
 #ifdef CONFIG_IPV6
         else if (skb->protocol == htons(ETH_P_IPV6)) {
-                struct rt6_info *rt6 = (struct rt6_info *)skb->dst;
+                struct rt6_info *rt6 = (struct rt6_info *)skb_dst(skb);
 
-                if (rt6 && mtu < dst_mtu(skb->dst) && mtu >= IPV6_MIN_MTU) {
+                if (rt6 && mtu < dst_mtu(skb_dst(skb)) && mtu >= IPV6_MIN_MTU) {
                         if ((tunnel->parms.iph.daddr &&
                              !ipv4_is_multicast(tunnel->parms.iph.daddr)) ||
                             rt6->rt6i_dst.plen == 128) {
                                 rt6->rt6i_flags |= RTF_MODIFIED;
-                                skb->dst->metrics[RTAX_MTU-1] = mtu;
+                                skb_dst(skb)->metrics[RTAX_MTU-1] = mtu;
                         }
                 }
 
@@ -837,8 +836,8 @@ static int ipgre_tunnel_xmit(struct sk_buff *skb, struct net_device *dev)
         memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
         IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
                               IPSKB_REROUTED);
-        dst_release(skb->dst);
-        skb->dst = &rt->u.dst;
+        skb_dst_drop(skb);
+        skb_dst_set(skb, &rt->u.dst);
 
         /*
          *      Push down and install the IPIP header.