[IPSEC]: Move dst->child loop from dst_ifdown to xfrm_dst_ifdown.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/core/dst.c

@@ -220,17 +220,17 @@ struct dst_entry *dst_destroy(struct dst_entry * dst)
  *
  * Commented and originally written by Alexey.
  */
-static void dst_ifdown(struct dst_entry *dst, int unregister)
+static inline void dst_ifdown(struct dst_entry *dst, int unregister)
 {
 	struct net_device *dev = dst->dev;
 
+	if (dst->ops->ifdown)
+		dst->ops->ifdown(dst, unregister);
+
 	if (!unregister) {
 		dst->input = dst_discard_in;
 		dst->output = dst_discard_out;
-	}
-
-	do {
-		if (unregister) {
+	} else {
 		dst->dev = &loopback_dev;
 		dev_hold(&loopback_dev);
 		dev_put(dev);
@@ -240,11 +240,6 @@ static void dst_ifdown(struct dst_entry *dst, int unregister)
 			dev_hold(&loopback_dev);
 		}
 	}
-
-		if (dst->ops->ifdown)
-			dst->ops->ifdown(dst, unregister);
-	} while ((dst = dst->child) && dst->flags & DST_NOHASH &&
-		 dst->dev == dev);
 }
 
 static int dst_dev_event(struct notifier_block *this, unsigned long event, void *ptr)

net/xfrm/xfrm_policy.c

@@ -1043,6 +1043,20 @@ static void xfrm_dst_destroy(struct dst_entry *dst)
 	dst->xfrm = NULL;
 }
 
+static void xfrm_dst_ifdown(struct dst_entry *dst, int unregister)
+{
+	struct net_device *dev = dst->dev;
+
+	if (!unregister)
+		return;
+
+	while ((dst = dst->child) && dst->xfrm && dst->dev == dev) {
+		dst->dev = &loopback_dev;
+		dev_hold(&loopback_dev);
+		dev_put(dev);
+	}
+}
+
 static void xfrm_link_failure(struct sk_buff *skb)
 {
 	/* Impossible. Such dst must be popped before reaches point of failure. */
@@ -1166,6 +1180,8 @@ int xfrm_policy_register_afinfo(struct xfrm_policy_afinfo *afinfo)
 			dst_ops->check = xfrm_dst_check;
 		if (likely(dst_ops->destroy == NULL))
 			dst_ops->destroy = xfrm_dst_destroy;
+		if (likely(dst_ops->ifdown == NULL))
+			dst_ops->ifdown = xfrm_dst_ifdown;
 		if (likely(dst_ops->negative_advice == NULL))
 			dst_ops->negative_advice = xfrm_negative_advice;
 		if (likely(dst_ops->link_failure == NULL))
@@ -1198,6 +1214,7 @@ int xfrm_policy_unregister_afinfo(struct xfrm_policy_afinfo *afinfo)
 			dst_ops->kmem_cachep = NULL;
 			dst_ops->check = NULL;
 			dst_ops->destroy = NULL;
+			dst_ops->ifdown = NULL;
 			dst_ops->negative_advice = NULL;
 			dst_ops->link_failure = NULL;
 			dst_ops->get_mss = NULL;