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, 30 insertions, 30 deletions

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 735a2bf4b5f1..c8dc8e5a822f 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -78,7 +78,7 @@ int __ip6_local_out(struct sk_buff *skb)
 		len = 0;
 	ipv6_hdr(skb)->payload_len = htons(len);
 
-	return nf_hook(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, skb->dst->dev,
+	return nf_hook(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, skb_dst(skb)->dev,
 		       dst_output);
 }
 
@@ -96,7 +96,7 @@ EXPORT_SYMBOL_GPL(ip6_local_out);
 
 static int ip6_output_finish(struct sk_buff *skb)
 {
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = skb_dst(skb);
 
 	if (dst->hh)
 		return neigh_hh_output(dst->hh, skb);
@@ -117,7 +117,7 @@ static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
 	__skb_pull(newskb, skb_network_offset(newskb));
 	newskb->pkt_type = PACKET_LOOPBACK;
 	newskb->ip_summed = CHECKSUM_UNNECESSARY;
-	WARN_ON(!newskb->dst);
+	WARN_ON(!skb_dst(newskb));
 
 	netif_rx(newskb);
 	return 0;
@@ -126,7 +126,7 @@ static int ip6_dev_loopback_xmit(struct sk_buff *newskb)
 
 static int ip6_output2(struct sk_buff *skb)
 {
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = skb_dst(skb);
 	struct net_device *dev = dst->dev;
 
 	skb->protocol = htons(ETH_P_IPV6);
@@ -134,7 +134,7 @@ static int ip6_output2(struct sk_buff *skb)
 
 	if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
 		struct ipv6_pinfo* np = skb->sk ? inet6_sk(skb->sk) : NULL;
-		struct inet6_dev *idev = ip6_dst_idev(skb->dst);
+		struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
 
 		if (!(dev->flags & IFF_LOOPBACK) && (!np || np->mc_loop) &&
 		    ((mroute6_socket(dev_net(dev)) &&
@@ -172,21 +172,21 @@ static inline int ip6_skb_dst_mtu(struct sk_buff *skb)
 	struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
 
 	return (np && np->pmtudisc == IPV6_PMTUDISC_PROBE) ?
-	       skb->dst->dev->mtu : dst_mtu(skb->dst);
+	       skb_dst(skb)->dev->mtu : dst_mtu(skb_dst(skb));
 }
 
 int ip6_output(struct sk_buff *skb)
 {
-	struct inet6_dev *idev = ip6_dst_idev(skb->dst);
+	struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
 	if (unlikely(idev->cnf.disable_ipv6)) {
-		IP6_INC_STATS(dev_net(skb->dst->dev), idev,
+		IP6_INC_STATS(dev_net(skb_dst(skb)->dev), idev,
 			      IPSTATS_MIB_OUTDISCARDS);
 		kfree_skb(skb);
 		return 0;
 	}
 
 	if ((skb->len > ip6_skb_dst_mtu(skb) && !skb_is_gso(skb)) ||
-				dst_allfrag(skb->dst))
+				dst_allfrag(skb_dst(skb)))
 		return ip6_fragment(skb, ip6_output2);
 	else
 		return ip6_output2(skb);
@@ -202,7 +202,7 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
 	struct net *net = sock_net(sk);
 	struct ipv6_pinfo *np = inet6_sk(sk);
 	struct in6_addr *first_hop = &fl->fl6_dst;
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = skb_dst(skb);
 	struct ipv6hdr *hdr;
 	u8  proto = fl->proto;
 	int seg_len = skb->len;
@@ -222,7 +222,7 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
 		if (skb_headroom(skb) < head_room) {
 			struct sk_buff *skb2 = skb_realloc_headroom(skb, head_room);
 			if (skb2 == NULL) {
-				IP6_INC_STATS(net, ip6_dst_idev(skb->dst),
+				IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
 					      IPSTATS_MIB_OUTDISCARDS);
 				kfree_skb(skb);
 				return -ENOBUFS;
@@ -276,7 +276,7 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
 
 	mtu = dst_mtu(dst);
 	if ((skb->len <= mtu) || skb->local_df || skb_is_gso(skb)) {
-		IP6_UPD_PO_STATS(net, ip6_dst_idev(skb->dst),
+		IP6_UPD_PO_STATS(net, ip6_dst_idev(skb_dst(skb)),
 			      IPSTATS_MIB_OUT, skb->len);
 		return NF_HOOK(PF_INET6, NF_INET_LOCAL_OUT, skb, NULL, dst->dev,
 				dst_output);
@@ -286,7 +286,7 @@ int ip6_xmit(struct sock *sk, struct sk_buff *skb, struct flowi *fl,
 		printk(KERN_DEBUG "IPv6: sending pkt_too_big to self\n");
 	skb->dev = dst->dev;
 	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
-	IP6_INC_STATS(net, ip6_dst_idev(skb->dst), IPSTATS_MIB_FRAGFAILS);
+	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)), IPSTATS_MIB_FRAGFAILS);
 	kfree_skb(skb);
 	return -EMSGSIZE;
 }
@@ -416,7 +416,7 @@ static inline int ip6_forward_finish(struct sk_buff *skb)
 
 int ip6_forward(struct sk_buff *skb)
 {
-	struct dst_entry *dst = skb->dst;
+	struct dst_entry *dst = skb_dst(skb);
 	struct ipv6hdr *hdr = ipv6_hdr(skb);
 	struct inet6_skb_parm *opt = IP6CB(skb);
 	struct net *net = dev_net(dst->dev);
@@ -485,7 +485,7 @@ int ip6_forward(struct sk_buff *skb)
 		IP6_INC_STATS(net, ip6_dst_idev(dst), IPSTATS_MIB_INDISCARDS);
 		goto drop;
 	}
-	dst = skb->dst;
+	dst = skb_dst(skb);
 
 	/* IPv6 specs say nothing about it, but it is clear that we cannot
 	   send redirects to source routed frames.
@@ -566,8 +566,8 @@ static void ip6_copy_metadata(struct sk_buff *to, struct sk_buff *from)
 	to->pkt_type = from->pkt_type;
 	to->priority = from->priority;
 	to->protocol = from->protocol;
-	dst_release(to->dst);
-	to->dst = dst_clone(from->dst);
+	skb_dst_drop(to);
+	skb_dst_set(to, dst_clone(skb_dst(from)));
 	to->dev = from->dev;
 	to->mark = from->mark;
 
@@ -624,7 +624,7 @@ int ip6_find_1stfragopt(struct sk_buff *skb, u8 **nexthdr)
 static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
 {
 	struct sk_buff *frag;
-	struct rt6_info *rt = (struct rt6_info*)skb->dst;
+	struct rt6_info *rt = (struct rt6_info*)skb_dst(skb);
 	struct ipv6_pinfo *np = skb->sk ? inet6_sk(skb->sk) : NULL;
 	struct ipv6hdr *tmp_hdr;
 	struct frag_hdr *fh;
@@ -632,7 +632,7 @@ static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
 	__be32 frag_id = 0;
 	int ptr, offset = 0, err=0;
 	u8 *prevhdr, nexthdr = 0;
-	struct net *net = dev_net(skb->dst->dev);
+	struct net *net = dev_net(skb_dst(skb)->dev);
 
 	hlen = ip6_find_1stfragopt(skb, &prevhdr);
 	nexthdr = *prevhdr;
@@ -644,9 +644,9 @@ static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
 	 * check should be redundant, but it's free.)
 	 */
 	if (!skb->local_df) {
-		skb->dev = skb->dst->dev;
+		skb->dev = skb_dst(skb)->dev;
 		icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu, skb->dev);
-		IP6_INC_STATS(net, ip6_dst_idev(skb->dst),
+		IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
 			      IPSTATS_MIB_FRAGFAILS);
 		kfree_skb(skb);
 		return -EMSGSIZE;
@@ -696,7 +696,7 @@ static int ip6_fragment(struct sk_buff *skb, int (*output)(struct sk_buff *))
 		*prevhdr = NEXTHDR_FRAGMENT;
 		tmp_hdr = kmemdup(skb_network_header(skb), hlen, GFP_ATOMIC);
 		if (!tmp_hdr) {
-			IP6_INC_STATS(net, ip6_dst_idev(skb->dst),
+			IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
 				      IPSTATS_MIB_FRAGFAILS);
 			return -ENOMEM;
 		}
@@ -809,7 +809,7 @@ slow_path:
 
 		if ((frag = alloc_skb(len+hlen+sizeof(struct frag_hdr)+LL_ALLOCATED_SPACE(rt->u.dst.dev), GFP_ATOMIC)) == NULL) {
 			NETDEBUG(KERN_INFO "IPv6: frag: no memory for new fragment!\n");
-			IP6_INC_STATS(net, ip6_dst_idev(skb->dst),
+			IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
 				      IPSTATS_MIB_FRAGFAILS);
 			err = -ENOMEM;
 			goto fail;
@@ -873,16 +873,16 @@ slow_path:
 		if (err)
 			goto fail;
 
-		IP6_INC_STATS(net, ip6_dst_idev(skb->dst),
+		IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
 			      IPSTATS_MIB_FRAGCREATES);
 	}
-	IP6_INC_STATS(net, ip6_dst_idev(skb->dst),
+	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
 		      IPSTATS_MIB_FRAGOKS);
 	kfree_skb(skb);
 	return err;
 
 fail:
-	IP6_INC_STATS(net, ip6_dst_idev(skb->dst),
+	IP6_INC_STATS(net, ip6_dst_idev(skb_dst(skb)),
 		      IPSTATS_MIB_FRAGFAILS);
 	kfree_skb(skb);
 	return err;
@@ -1516,10 +1516,10 @@ int ip6_push_pending_frames(struct sock *sk)
 	skb->priority = sk->sk_priority;
 	skb->mark = sk->sk_mark;
 
-	skb->dst = dst_clone(&rt->u.dst);
+	skb_dst_set(skb, dst_clone(&rt->u.dst));
 	IP6_UPD_PO_STATS(net, rt->rt6i_idev, IPSTATS_MIB_OUT, skb->len);
 	if (proto == IPPROTO_ICMPV6) {
-		struct inet6_dev *idev = ip6_dst_idev(skb->dst);
+		struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
 
 		ICMP6MSGOUT_INC_STATS_BH(net, idev, icmp6_hdr(skb)->icmp6_type);
 		ICMP6_INC_STATS_BH(net, idev, ICMP6_MIB_OUTMSGS);
@@ -1545,8 +1545,8 @@ void ip6_flush_pending_frames(struct sock *sk)
 	struct sk_buff *skb;
 
 	while ((skb = __skb_dequeue_tail(&sk->sk_write_queue)) != NULL) {
-		if (skb->dst)
-			IP6_INC_STATS(sock_net(sk), ip6_dst_idev(skb->dst),
+		if (skb_dst(skb))
+			IP6_INC_STATS(sock_net(sk), ip6_dst_idev(skb_dst(skb)),
 				      IPSTATS_MIB_OUTDISCARDS);
 		kfree_skb(skb);
 	}