[IPV4]: Add 'rtable' field in struct sk_buff to alias 'dst' and avoid casts

(Anonymous) unions can help us to avoid ugly casts.

A common cast it the (struct rtable *)skb->dst one.

Defining an union like  :
union {
     struct dst_entry *dst;
     struct rtable *rtable;
};
permits to use skb->rtable in place.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 3 deletions

diff --git a/net/ipv4/ipmr.c b/net/ipv4/ipmr.c
index a94f52c207a7..7d63d74ef62a 100644
--- a/net/ipv4/ipmr.c
+++ b/net/ipv4/ipmr.c
@@ -1283,7 +1283,7 @@ static int ip_mr_forward(struct sk_buff *skb, struct mfc_cache *cache, int local
         if (vif_table[vif].dev != skb->dev) {
                 int true_vifi;
 
-                if (((struct rtable*)skb->dst)->fl.iif == 0) {
+                if (skb->rtable->fl.iif == 0) {
                         /* It is our own packet, looped back.
                            Very complicated situation...
 
@@ -1357,7 +1357,7 @@ dont_forward:
 int ip_mr_input(struct sk_buff *skb)
 {
         struct mfc_cache *cache;
-        int local = ((struct rtable*)skb->dst)->rt_flags&RTCF_LOCAL;
+        int local = skb->rtable->rt_flags&RTCF_LOCAL;
 
         /* Packet is looped back after forward, it should not be
            forwarded second time, but still can be delivered locally.
@@ -1594,7 +1594,7 @@ int ipmr_get_route(struct sk_buff *skb, struct rtmsg *rtm, int nowait)
 {
         int err;
         struct mfc_cache *cache;
-        struct rtable *rt = (struct rtable*)skb->dst;
+        struct rtable *rt = skb->rtable;
 
         read_lock(&mrt_lock);
         cache = ipmr_cache_find(rt->rt_src, rt->rt_dst);