net: Abstract dst->neighbour accesses behind helpers.

dst_{get,set}_neighbour()
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/infiniband/core/addr.c

@@ -215,7 +215,7 @@ static int addr4_resolve(struct sockaddr_in *src_in,
 
 	neigh = neigh_lookup(&arp_tbl, &rt->rt_gateway, rt->dst.dev);
 	if (!neigh || !(neigh->nud_state & NUD_VALID)) {
-		neigh_event_send(rt->dst.neighbour, NULL);
+		neigh_event_send(dst_get_neighbour(&rt->dst), NULL);
 		ret = -ENODATA;
 		if (neigh)
 			goto release;
@@ -273,9 +273,10 @@ static int addr6_resolve(struct sockaddr_in6 *src_in,
 		goto put;
 	}
 
-	neigh = dst->neighbour;
+	neigh = dst_get_neighbour(dst);
 	if (!neigh || !(neigh->nud_state & NUD_VALID)) {
-		neigh_event_send(dst->neighbour, NULL);
+		if (neigh)
+			neigh_event_send(neigh, NULL);
 		ret = -ENODATA;
 		goto put;
 	}

drivers/infiniband/hw/cxgb3/iwch_cm.c

@@ -1328,6 +1328,7 @@ static int pass_accept_req(struct t3cdev *tdev, struct sk_buff *skb, void *ctx)
 	struct iwch_ep *child_ep, *parent_ep = ctx;
 	struct cpl_pass_accept_req *req = cplhdr(skb);
 	unsigned int hwtid = GET_TID(req);
+	struct neighbour *neigh;
 	struct dst_entry *dst;
 	struct l2t_entry *l2t;
 	struct rtable *rt;
@@ -1364,7 +1365,8 @@ static int pass_accept_req(struct t3cdev *tdev, struct sk_buff *skb, void *ctx)
 		goto reject;
 	}
 	dst = &rt->dst;
-	l2t = t3_l2t_get(tdev, dst->neighbour, dst->neighbour->dev);
+	neigh = dst_get_neighbour(dst);
+	l2t = t3_l2t_get(tdev, neigh, neigh->dev);
 	if (!l2t) {
 		printk(KERN_ERR MOD "%s - failed to allocate l2t entry!\n",
 		       __func__);
@@ -1874,10 +1876,11 @@ static int is_loopback_dst(struct iw_cm_id *cm_id)
 
 int iwch_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
 {
-	int err = 0;
 	struct iwch_dev *h = to_iwch_dev(cm_id->device);
+	struct neighbour *neigh;
 	struct iwch_ep *ep;
 	struct rtable *rt;
+	int err = 0;
 
 	if (is_loopback_dst(cm_id)) {
 		err = -ENOSYS;
@@ -1933,9 +1936,10 @@ int iwch_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
 	}
 	ep->dst = &rt->dst;
 
+	neigh = dst_get_neighbour(ep->dst);
+
 	/* get a l2t entry */
-	ep->l2t = t3_l2t_get(ep->com.tdev, ep->dst->neighbour,
-			     ep->dst->neighbour->dev);
+	ep->l2t = t3_l2t_get(ep->com.tdev, neigh, neigh->dev);
 	if (!ep->l2t) {
 		printk(KERN_ERR MOD "%s - cannot alloc l2e.\n", __func__);
 		err = -ENOMEM;

drivers/infiniband/hw/cxgb4/cm.c

@@ -1325,6 +1325,7 @@ static int pass_accept_req(struct c4iw_dev *dev, struct sk_buff *skb)
 	unsigned int stid = GET_POPEN_TID(ntohl(req->tos_stid));
 	struct tid_info *t = dev->rdev.lldi.tids;
 	unsigned int hwtid = GET_TID(req);
+	struct neighbour *neigh;
 	struct dst_entry *dst;
 	struct l2t_entry *l2t;
 	struct rtable *rt;
@@ -1357,11 +1358,11 @@ static int pass_accept_req(struct c4iw_dev *dev, struct sk_buff *skb)
 		goto reject;
 	}
 	dst = &rt->dst;
-	if (dst->neighbour->dev->flags & IFF_LOOPBACK) {
+	neigh = dst_get_neighbour(dst);
+	if (neigh->dev->flags & IFF_LOOPBACK) {
 		pdev = ip_dev_find(&init_net, peer_ip);
 		BUG_ON(!pdev);
-		l2t = cxgb4_l2t_get(dev->rdev.lldi.l2t, dst->neighbour,
-				    pdev, 0);
+		l2t = cxgb4_l2t_get(dev->rdev.lldi.l2t, neigh, pdev, 0);
 		mtu = pdev->mtu;
 		tx_chan = cxgb4_port_chan(pdev);
 		smac_idx = (cxgb4_port_viid(pdev) & 0x7F) << 1;
@@ -1372,17 +1373,16 @@ static int pass_accept_req(struct c4iw_dev *dev, struct sk_buff *skb)
 		rss_qid = dev->rdev.lldi.rxq_ids[cxgb4_port_idx(pdev) * step];
 		dev_put(pdev);
 	} else {
-		l2t = cxgb4_l2t_get(dev->rdev.lldi.l2t, dst->neighbour,
-					dst->neighbour->dev, 0);
+		l2t = cxgb4_l2t_get(dev->rdev.lldi.l2t, neigh, neigh->dev, 0);
 		mtu = dst_mtu(dst);
-		tx_chan = cxgb4_port_chan(dst->neighbour->dev);
-		smac_idx = (cxgb4_port_viid(dst->neighbour->dev) & 0x7F) << 1;
+		tx_chan = cxgb4_port_chan(neigh->dev);
+		smac_idx = (cxgb4_port_viid(neigh->dev) & 0x7F) << 1;
 		step = dev->rdev.lldi.ntxq / dev->rdev.lldi.nchan;
-		txq_idx = cxgb4_port_idx(dst->neighbour->dev) * step;
-		ctrlq_idx = cxgb4_port_idx(dst->neighbour->dev);
+		txq_idx = cxgb4_port_idx(neigh->dev) * step;
+		ctrlq_idx = cxgb4_port_idx(neigh->dev);
 		step = dev->rdev.lldi.nrxq / dev->rdev.lldi.nchan;
 		rss_qid = dev->rdev.lldi.rxq_ids[
-			  cxgb4_port_idx(dst->neighbour->dev) * step];
+			  cxgb4_port_idx(neigh->dev) * step];
 	}
 	if (!l2t) {
 		printk(KERN_ERR MOD "%s - failed to allocate l2t entry!\n",
@@ -1847,6 +1847,7 @@ int c4iw_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
 	struct c4iw_ep *ep;
 	struct rtable *rt;
 	struct net_device *pdev;
+	struct neighbour *neigh;
 	int step;
 
 	if ((conn_param->ord > c4iw_max_read_depth) ||
@@ -1908,14 +1909,15 @@ int c4iw_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
 	}
 	ep->dst = &rt->dst;
 
+	neigh = dst_get_neighbour(ep->dst);
+
 	/* get a l2t entry */
-	if (ep->dst->neighbour->dev->flags & IFF_LOOPBACK) {
+	if (neigh->dev->flags & IFF_LOOPBACK) {
 		PDBG("%s LOOPBACK\n", __func__);
 		pdev = ip_dev_find(&init_net,
 				   cm_id->remote_addr.sin_addr.s_addr);
 		ep->l2t = cxgb4_l2t_get(ep->com.dev->rdev.lldi.l2t,
-					ep->dst->neighbour,
-					pdev, 0);
+					neigh, pdev, 0);
 		ep->mtu = pdev->mtu;
 		ep->tx_chan = cxgb4_port_chan(pdev);
 		ep->smac_idx = (cxgb4_port_viid(pdev) & 0x7F) << 1;
@@ -1930,20 +1932,18 @@ int c4iw_connect(struct iw_cm_id *cm_id, struct iw_cm_conn_param *conn_param)
 		dev_put(pdev);
 	} else {
 		ep->l2t = cxgb4_l2t_get(ep->com.dev->rdev.lldi.l2t,
-					ep->dst->neighbour,
-					ep->dst->neighbour->dev, 0);
+					neigh, neigh->dev, 0);
 		ep->mtu = dst_mtu(ep->dst);
-		ep->tx_chan = cxgb4_port_chan(ep->dst->neighbour->dev);
-		ep->smac_idx = (cxgb4_port_viid(ep->dst->neighbour->dev) &
-				0x7F) << 1;
+		ep->tx_chan = cxgb4_port_chan(neigh->dev);
+		ep->smac_idx = (cxgb4_port_viid(neigh->dev) & 0x7F) << 1;
 		step = ep->com.dev->rdev.lldi.ntxq /
 		       ep->com.dev->rdev.lldi.nchan;
-		ep->txq_idx = cxgb4_port_idx(ep->dst->neighbour->dev) * step;
-		ep->ctrlq_idx = cxgb4_port_idx(ep->dst->neighbour->dev);
+		ep->txq_idx = cxgb4_port_idx(neigh->dev) * step;
+		ep->ctrlq_idx = cxgb4_port_idx(neigh->dev);
 		step = ep->com.dev->rdev.lldi.nrxq /
 		       ep->com.dev->rdev.lldi.nchan;
 		ep->rss_qid = ep->com.dev->rdev.lldi.rxq_ids[
-			      cxgb4_port_idx(ep->dst->neighbour->dev) * step];
+			      cxgb4_port_idx(neigh->dev) * step];
 	}
 	if (!ep->l2t) {
 		printk(KERN_ERR MOD "%s - cannot alloc l2e.\n", __func__);

drivers/infiniband/hw/nes/nes_cm.c

@@ -1151,7 +1151,7 @@ static int nes_addr_resolve_neigh(struct nes_vnic *nesvnic, u32 dst_ip, int arpi
 	}
 
 	if ((neigh == NULL) || (!(neigh->nud_state & NUD_VALID)))
-		neigh_event_send(rt->dst.neighbour, NULL);
+		neigh_event_send(dst_get_neighbour(&rt->dst), NULL);
 
 	ip_rt_put(rt);
 	return rc;

drivers/infiniband/ulp/ipoib/ipoib_main.c

@@ -560,9 +560,11 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_path *path;
 	struct ipoib_neigh *neigh;
+	struct neighbour *n;
 	unsigned long flags;
 
-	neigh = ipoib_neigh_alloc(skb_dst(skb)->neighbour, skb->dev);
+	n = dst_get_neighbour(skb_dst(skb));
+	neigh = ipoib_neigh_alloc(n, skb->dev);
 	if (!neigh) {
 		++dev->stats.tx_dropped;
 		dev_kfree_skb_any(skb);
@@ -571,9 +573,9 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
 
 	spin_lock_irqsave(&priv->lock, flags);
 
-	path = __path_find(dev, skb_dst(skb)->neighbour->ha + 4);
+	path = __path_find(dev, n->ha + 4);
 	if (!path) {
-		path = path_rec_create(dev, skb_dst(skb)->neighbour->ha + 4);
+		path = path_rec_create(dev, n->ha + 4);
 		if (!path)
 			goto err_path;
 
@@ -607,7 +609,7 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
 			}
 		} else {
 			spin_unlock_irqrestore(&priv->lock, flags);
-			ipoib_send(dev, skb, path->ah, IPOIB_QPN(skb_dst(skb)->neighbour->ha));
+			ipoib_send(dev, skb, path->ah, IPOIB_QPN(n->ha));
 			return;
 		}
 	} else {
@@ -637,17 +639,20 @@ static void neigh_add_path(struct sk_buff *skb, struct net_device *dev)
 static void ipoib_path_lookup(struct sk_buff *skb, struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(skb->dev);
+	struct dst_entry *dst = skb_dst(skb);
+	struct neighbour *n;
 
 	/* Look up path record for unicasts */
-	if (skb_dst(skb)->neighbour->ha[4] != 0xff) {
+	n = dst_get_neighbour(dst);
+	if (n->ha[4] != 0xff) {
 		neigh_add_path(skb, dev);
 		return;
 	}
 
 	/* Add in the P_Key for multicasts */
-	skb_dst(skb)->neighbour->ha[8] = (priv->pkey >> 8) & 0xff;
-	skb_dst(skb)->neighbour->ha[9] = priv->pkey & 0xff;
-	ipoib_mcast_send(dev, skb_dst(skb)->neighbour->ha + 4, skb);
+	n->ha[8] = (priv->pkey >> 8) & 0xff;
+	n->ha[9] = priv->pkey & 0xff;
+	ipoib_mcast_send(dev, n->ha + 4, skb);
 }
 
 static void unicast_arp_send(struct sk_buff *skb, struct net_device *dev,
@@ -712,18 +717,20 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
 {
 	struct ipoib_dev_priv *priv = netdev_priv(dev);
 	struct ipoib_neigh *neigh;
+	struct neighbour *n;
 	unsigned long flags;
 
-	if (likely(skb_dst(skb) && skb_dst(skb)->neighbour)) {
-		if (unlikely(!*to_ipoib_neigh(skb_dst(skb)->neighbour))) {
+	n = dst_get_neighbour(skb_dst(skb));
+	if (likely(skb_dst(skb) && n)) {
+		if (unlikely(!*to_ipoib_neigh(n))) {
 			ipoib_path_lookup(skb, dev);
 			return NETDEV_TX_OK;
 		}
 
-		neigh = *to_ipoib_neigh(skb_dst(skb)->neighbour);
+		neigh = *to_ipoib_neigh(n);
 
 		if (unlikely((memcmp(&neigh->dgid.raw,
-				     skb_dst(skb)->neighbour->ha + 4,
+				     n->ha + 4,
 				     sizeof(union ib_gid))) ||
 			     (neigh->dev != dev))) {
 			spin_lock_irqsave(&priv->lock, flags);
@@ -749,7 +756,7 @@ static int ipoib_start_xmit(struct sk_buff *skb, struct net_device *dev)
 				return NETDEV_TX_OK;
 			}
 		} else if (neigh->ah) {
-			ipoib_send(dev, skb, neigh->ah, IPOIB_QPN(skb_dst(skb)->neighbour->ha));
+			ipoib_send(dev, skb, neigh->ah, IPOIB_QPN(n->ha));
 			return NETDEV_TX_OK;
 		}
 
@@ -812,6 +819,8 @@ static int ipoib_hard_header(struct sk_buff *skb,
 			     const void *daddr, const void *saddr, unsigned len)
 {
 	struct ipoib_header *header;
+	struct dst_entry *dst;
+	struct neighbour *n;
 
 	header = (struct ipoib_header *) skb_push(skb, sizeof *header);
 
@@ -823,7 +832,11 @@ static int ipoib_hard_header(struct sk_buff *skb,
 	 * destination address onto the front of the skb so we can
 	 * figure out where to send the packet later.
 	 */
-	if ((!skb_dst(skb) || !skb_dst(skb)->neighbour) && daddr) {
+	dst = skb_dst(skb);
+	n = NULL;
+	if (dst)
+		n = dst_get_neighbour(dst);
+	if ((!dst || !n) && daddr) {
 		struct ipoib_pseudoheader *phdr =
 			(struct ipoib_pseudoheader *) skb_push(skb, sizeof *phdr);
 		memcpy(phdr->hwaddr, daddr, INFINIBAND_ALEN);

drivers/infiniband/ulp/ipoib/ipoib_multicast.c

@@ -258,11 +258,15 @@ static int ipoib_mcast_join_finish(struct ipoib_mcast *mcast,
 	netif_tx_lock_bh(dev);
 	while (!skb_queue_empty(&mcast->pkt_queue)) {
 		struct sk_buff *skb = skb_dequeue(&mcast->pkt_queue);
+		struct dst_entry *dst = skb_dst(skb);
+		struct neighbour *n = NULL;
+
 		netif_tx_unlock_bh(dev);
 
 		skb->dev = dev;
-
-		if (!skb_dst(skb) || !skb_dst(skb)->neighbour) {
+		if (dst)
+			n = dst_get_neighbour(dst);
+		if (!dst || !n) {
 			/* put pseudoheader back on for next time */
 			skb_push(skb, sizeof (struct ipoib_pseudoheader));
 		}
@@ -715,11 +719,13 @@ void ipoib_mcast_send(struct net_device *dev, void *mgid, struct sk_buff *skb)
 
 out:
 	if (mcast && mcast->ah) {
-		if (skb_dst(skb)		&&
-		    skb_dst(skb)->neighbour &&
-		    !*to_ipoib_neigh(skb_dst(skb)->neighbour)) {
-			struct ipoib_neigh *neigh = ipoib_neigh_alloc(skb_dst(skb)->neighbour,
-									skb->dev);
+		struct dst_entry *dst = skb_dst(skb);
+		struct neighbour *n = NULL;
+		if (dst)
+			n = dst_get_neighbour(dst);
+		if (n && !*to_ipoib_neigh(n)) {
+			struct ipoib_neigh *neigh = ipoib_neigh_alloc(n,
+								      skb->dev);
 
 			if (neigh) {
 				kref_get(&mcast->ah->ref);

drivers/net/cxgb3/cxgb3_offload.c

@@ -971,7 +971,7 @@ static int nb_callback(struct notifier_block *self, unsigned long event,
 	case (NETEVENT_REDIRECT):{
 		struct netevent_redirect *nr = ctx;
 		cxgb_redirect(nr->old, nr->new);
-		cxgb_neigh_update(nr->new->neighbour);
+		cxgb_neigh_update(dst_get_neighbour(nr->new));
 		break;
 	}
 	default:
@@ -1116,8 +1116,8 @@ static void cxgb_redirect(struct dst_entry *old, struct dst_entry *new)
 	struct l2t_entry *e;
 	struct t3c_tid_entry *te;
 
-	olddev = old->neighbour->dev;
-	newdev = new->neighbour->dev;
+	olddev = dst_get_neighbour(old)->dev;
+	newdev = dst_get_neighbour(new)->dev;
 	if (!is_offloading(olddev))
 		return;
 	if (!is_offloading(newdev)) {
@@ -1134,7 +1134,7 @@ static void cxgb_redirect(struct dst_entry *old, struct dst_entry *new)
 	}
 
 	/* Add new L2T entry */
-	e = t3_l2t_get(tdev, new->neighbour, newdev);
+	e = t3_l2t_get(tdev, dst_get_neighbour(new), newdev);
 	if (!e) {
 		printk(KERN_ERR "%s: couldn't allocate new l2t entry!\n",
 		       __func__);

drivers/s390/net/qeth_l3_main.c

@@ -2742,9 +2742,14 @@ static int qeth_l3_do_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
 int inline qeth_l3_get_cast_type(struct qeth_card *card, struct sk_buff *skb)
 {
 	int cast_type = RTN_UNSPEC;
-
-	if (skb_dst(skb) && skb_dst(skb)->neighbour) {
-		cast_type = skb_dst(skb)->neighbour->type;
+	struct neighbour *n = NULL;
+	struct dst_entry *dst;
+
+	dst = skb_dst(skb);
+	if (dst)
+		n = dst_get_neighbour(dst);
+	if (n) {
+		cast_type = n->type;
 		if ((cast_type == RTN_BROADCAST) ||
 		    (cast_type == RTN_MULTICAST) ||
 		    (cast_type == RTN_ANYCAST))
@@ -2787,6 +2792,9 @@ int inline qeth_l3_get_cast_type(struct qeth_card *card, struct sk_buff *skb)
 static void qeth_l3_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
 		struct sk_buff *skb, int ipv, int cast_type)
 {
+	struct neighbour *n = NULL;
+	struct dst_entry *dst;
+
 	memset(hdr, 0, sizeof(struct qeth_hdr));
 	hdr->hdr.l3.id = QETH_HEADER_TYPE_LAYER3;
 	hdr->hdr.l3.ext_flags = 0;
@@ -2804,13 +2812,16 @@ static void qeth_l3_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
 	}
 
 	hdr->hdr.l3.length = skb->len - sizeof(struct qeth_hdr);
+	dst = skb_dst(skb);
+	if (dst)
+		n = dst_get_neighbour(dst);
 	if (ipv == 4) {
 		/* IPv4 */
 		hdr->hdr.l3.flags = qeth_l3_get_qeth_hdr_flags4(cast_type);
 		memset(hdr->hdr.l3.dest_addr, 0, 12);
-		if ((skb_dst(skb)) && (skb_dst(skb)->neighbour)) {
+		if (n) {
 			*((u32 *) (&hdr->hdr.l3.dest_addr[12])) =
-			    *((u32 *) skb_dst(skb)->neighbour->primary_key);
+			    *((u32 *) n->primary_key);
 		} else {
 			/* fill in destination address used in ip header */
 			*((u32 *) (&hdr->hdr.l3.dest_addr[12])) =
@@ -2821,9 +2832,9 @@ static void qeth_l3_fill_header(struct qeth_card *card, struct qeth_hdr *hdr,
 		hdr->hdr.l3.flags = qeth_l3_get_qeth_hdr_flags6(cast_type);
 		if (card->info.type == QETH_CARD_TYPE_IQD)
 			hdr->hdr.l3.flags &= ~QETH_HDR_PASSTHRU;
-		if ((skb_dst(skb)) && (skb_dst(skb)->neighbour)) {
+		if (n) {
 			memcpy(hdr->hdr.l3.dest_addr,
-			       skb_dst(skb)->neighbour->primary_key, 16);
+			       n->primary_key, 16);
 		} else {
 			/* fill in destination address used in ip header */
 			memcpy(hdr->hdr.l3.dest_addr,

drivers/scsi/cxgbi/cxgb3i/cxgb3i.c

@@ -985,7 +985,7 @@ static int init_act_open(struct cxgbi_sock *csk)
 		csk->saddr.sin_addr.s_addr = chba->ipv4addr;
 
 	csk->rss_qid = 0;
-	csk->l2t = t3_l2t_get(t3dev, dst->neighbour, ndev);
+	csk->l2t = t3_l2t_get(t3dev, dst_get_neighbour(dst), ndev);
 	if (!csk->l2t) {
 		pr_err("NO l2t available.\n");
 		return -EINVAL;

drivers/scsi/cxgbi/cxgb4i/cxgb4i.c

@@ -1160,7 +1160,7 @@ static int init_act_open(struct cxgbi_sock *csk)
 	cxgbi_sock_set_flag(csk, CTPF_HAS_ATID);
 	cxgbi_sock_get(csk);
 
-	csk->l2t = cxgb4_l2t_get(lldi->l2t, csk->dst->neighbour, ndev, 0);
+	csk->l2t = cxgb4_l2t_get(lldi->l2t, dst_get_neighbour(csk->dst), ndev, 0);
 	if (!csk->l2t) {
 		pr_err("%s, cannot alloc l2t.\n", ndev->name);
 		goto rel_resource;

drivers/scsi/cxgbi/libcxgbi.c

@@ -492,7 +492,7 @@ static struct cxgbi_sock *cxgbi_check_route(struct sockaddr *dst_addr)
 		goto err_out;
 	}
 	dst = &rt->dst;
-	ndev = dst->neighbour->dev;
+	ndev = dst_get_neighbour(dst)->dev;
 
 	if (rt->rt_flags & (RTCF_MULTICAST | RTCF_BROADCAST)) {
 		pr_info("multi-cast route %pI4, port %u, dev %s.\n",
@@ -506,7 +506,7 @@ static struct cxgbi_sock *cxgbi_check_route(struct sockaddr *dst_addr)
 		ndev = ip_dev_find(&init_net, daddr->sin_addr.s_addr);
 		mtu = ndev->mtu;
 		pr_info("rt dev %s, loopback -> %s, mtu %u.\n",
-			dst->neighbour->dev->name, ndev->name, mtu);
+			dst_get_neighbour(dst)->dev->name, ndev->name, mtu);
 	}
 
 	cdev = cxgbi_device_find_by_netdev(ndev, &port);

include/net/dst.h

@@ -37,7 +37,7 @@ struct dst_entry {
 	unsigned long		_metrics;
 	unsigned long		expires;
 	struct dst_entry	*path;
-	struct neighbour	*neighbour;
+	struct neighbour	*_neighbour;
 #ifdef CONFIG_XFRM
 	struct xfrm_state	*xfrm;
 #else
@@ -86,6 +86,16 @@ struct dst_entry {
 	};
 };
 
+static inline struct neighbour *dst_get_neighbour(struct dst_entry *dst)
+{
+	return dst->_neighbour;
+}
+
+static inline void dst_set_neighbour(struct dst_entry *dst, struct neighbour *neigh)
+{
+	dst->_neighbour = neigh;
+}
+
 extern u32 *dst_cow_metrics_generic(struct dst_entry *dst, unsigned long old);
 extern const u32 dst_default_metrics[RTAX_MAX];
 
@@ -371,8 +381,10 @@ static inline void dst_rcu_free(struct rcu_head *head)
 
 static inline void dst_confirm(struct dst_entry *dst)
 {
-	if (dst)
-		neigh_confirm(dst->neighbour);
+	if (dst) {
+		struct neighbour *n = dst_get_neighbour(dst);
+		neigh_confirm(n);
+	}
 }
 
 static inline void dst_link_failure(struct sk_buff *skb)

net/atm/clip.c

@@ -362,33 +362,37 @@ static netdev_tx_t clip_start_xmit(struct sk_buff *skb,
 				   struct net_device *dev)
 {
 	struct clip_priv *clip_priv = PRIV(dev);
+	struct dst_entry *dst = skb_dst(skb);
 	struct atmarp_entry *entry;
+	struct neighbour *n;
 	struct atm_vcc *vcc;
 	int old;
 	unsigned long flags;
 
 	pr_debug("(skb %p)\n", skb);
-	if (!skb_dst(skb)) {
+	if (!dst) {
 		pr_err("skb_dst(skb) == NULL\n");
 		dev_kfree_skb(skb);
 		dev->stats.tx_dropped++;
 		return NETDEV_TX_OK;
 	}
-	if (!skb_dst(skb)->neighbour) {
+	n = dst_get_neighbour(dst);
+	if (!n) {
 #if 0
-		skb_dst(skb)->neighbour = clip_find_neighbour(skb_dst(skb), 1);
-		if (!skb_dst(skb)->neighbour) {
+		n = clip_find_neighbour(skb_dst(skb), 1);
+		if (!n) {
 			dev_kfree_skb(skb);	/* lost that one */
 			dev->stats.tx_dropped++;
 			return 0;
 		}
+		dst_set_neighbour(dst, n);
 #endif
 		pr_err("NO NEIGHBOUR !\n");
 		dev_kfree_skb(skb);
 		dev->stats.tx_dropped++;
 		return NETDEV_TX_OK;
 	}
-	entry = NEIGH2ENTRY(skb_dst(skb)->neighbour);
+	entry = NEIGH2ENTRY(n);
 	if (!entry->vccs) {
 		if (time_after(jiffies, entry->expires)) {
 			/* should be resolved */
@@ -405,7 +409,7 @@ static netdev_tx_t clip_start_xmit(struct sk_buff *skb,
 	}
 	pr_debug("neigh %p, vccs %p\n", entry, entry->vccs);
 	ATM_SKB(skb)->vcc = vcc = entry->vccs->vcc;
-	pr_debug("using neighbour %p, vcc %p\n", skb_dst(skb)->neighbour, vcc);
+	pr_debug("using neighbour %p, vcc %p\n", n, vcc);
 	if (entry->vccs->encap) {
 		void *here;
 

net/bridge/br_netfilter.c

@@ -350,7 +350,7 @@ static int br_nf_pre_routing_finish_bridge(struct sk_buff *skb)
 	if (!skb->dev)
 		goto free_skb;
 	dst = skb_dst(skb);
-	neigh = dst->neighbour;
+	neigh = dst_get_neighbour(dst);
 	if (neigh->hh.hh_len) {
 		neigh_hh_bridge(&neigh->hh, skb);
 		skb->dev = nf_bridge->physindev;

net/core/dst.c

@@ -171,7 +171,7 @@ void *dst_alloc(struct dst_ops *ops, struct net_device *dev,
 	dst_init_metrics(dst, dst_default_metrics, true);
 	dst->expires = 0UL;
 	dst->path = dst;
-	dst->neighbour = NULL;
+	dst->_neighbour = NULL;
 #ifdef CONFIG_XFRM
 	dst->xfrm = NULL;
 #endif
@@ -229,11 +229,11 @@ struct dst_entry *dst_destroy(struct dst_entry * dst)
 	smp_rmb();
 
 again:
-	neigh = dst->neighbour;
+	neigh = dst->_neighbour;
 	child = dst->child;
 
 	if (neigh) {
-		dst->neighbour = NULL;
+		dst->_neighbour = NULL;
 		neigh_release(neigh);
 	}
 
@@ -363,8 +363,8 @@ static void dst_ifdown(struct dst_entry *dst, struct net_device *dev,
 		dst->dev = dev_net(dst->dev)->loopback_dev;
 		dev_hold(dst->dev);
 		dev_put(dev);
-		if (dst->neighbour && dst->neighbour->dev == dev) {
-			dst->neighbour->dev = dst->dev;
+		if (dst->_neighbour && dst->_neighbour->dev == dev) {
+			dst->_neighbour->dev = dst->dev;
 			dev_hold(dst->dev);
 			dev_put(dev);
 		}

net/core/neighbour.c

@@ -1153,11 +1153,12 @@ int neigh_update(struct neighbour *neigh, const u8 *lladdr, u8 new,
 
 		while (neigh->nud_state & NUD_VALID &&
 		       (skb = __skb_dequeue(&neigh->arp_queue)) != NULL) {
-			struct neighbour *n1 = neigh;
+			struct dst_entry *dst = skb_dst(skb);
+			struct neighbour *n2, *n1 = neigh;