ipv6: Remove fallback argument from ip6_hold_safe

net and null_fallback are redundant. Remove null_fallback in favor of
!net check.

Signed-off-by: David Ahern <dsahern@gmail.com>
Acked-by: Wei Wang <weiwan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/ipv6/route.c

@@ -1015,14 +1015,13 @@ static struct fib6_node* fib6_backtrack(struct fib6_node *fn,
 	}
 }
 
-static bool ip6_hold_safe(struct net *net, struct rt6_info **prt,
-			  bool null_fallback)
+static bool ip6_hold_safe(struct net *net, struct rt6_info **prt)
 {
 	struct rt6_info *rt = *prt;
 
 	if (dst_hold_safe(&rt->dst))
 		return true;
-	if (null_fallback) {
+	if (net) {
 		rt = net->ipv6.ip6_null_entry;
 		dst_hold(&rt->dst);
 	} else {
@@ -1089,7 +1088,7 @@ static struct rt6_info *ip6_pol_route_lookup(struct net *net,
 	/* Search through exception table */
 	rt = rt6_find_cached_rt(f6i, &fl6->daddr, &fl6->saddr);
 	if (rt) {
-		if (ip6_hold_safe(net, &rt, true))
+		if (ip6_hold_safe(net, &rt))
 			dst_use_noref(&rt->dst, jiffies);
 	} else if (f6i == net->ipv6.fib6_null_entry) {
 		rt = net->ipv6.ip6_null_entry;
@@ -1240,7 +1239,7 @@ static struct rt6_info *rt6_get_pcpu_route(struct fib6_info *rt)
 	pcpu_rt = *p;
 
 	if (pcpu_rt)
-		ip6_hold_safe(NULL, &pcpu_rt, false);
+		ip6_hold_safe(NULL, &pcpu_rt);
 
 	return pcpu_rt;
 }
@@ -1865,7 +1864,7 @@ struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
 	/*Search through exception table */
 	rt = rt6_find_cached_rt(f6i, &fl6->daddr, &fl6->saddr);
 	if (rt) {
-		if (ip6_hold_safe(net, &rt, true))
+		if (ip6_hold_safe(net, &rt))
 			dst_use_noref(&rt->dst, jiffies);
 
 		rcu_read_unlock();
@@ -2480,7 +2479,7 @@ static struct rt6_info *__ip6_route_redirect(struct net *net,
 
 out:
 	if (ret)
-		ip6_hold_safe(net, &ret, true);
+		ip6_hold_safe(net, &ret);
 	else
 		ret = ip6_create_rt_rcu(rt);