net: common metrics init helper for dst_entry

ipv4 and ipv6 both use refcounted metrics if FIB entries have metrics set.
Move the common initialization code to a helper and use for both protocols.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 12 insertions, 0 deletions

diff --git a/include/net/ip.h b/include/net/ip.h
index 8fdd58ce580d..f9a7125b4bda 100644
--- a/include/net/ip.h
+++ b/include/net/ip.h
@@ -429,6 +429,18 @@ static inline void ip_fib_metrics_put(struct dst_metrics *fib_metrics)
                 kfree(fib_metrics);
 }
 
+/* ipv4 and ipv6 both use refcounted metrics if it is not the default */
+static inline
+void ip_dst_init_metrics(struct dst_entry *dst, struct dst_metrics *fib_metrics)
+{
+        dst_init_metrics(dst, fib_metrics->metrics, true);
+
+        if (fib_metrics != &dst_default_metrics) {
+                dst->_metrics |= DST_METRICS_REFCOUNTED;
+                refcount_inc(&fib_metrics->refcnt);
+        }
+}
+
 u32 ip_idents_reserve(u32 hash, int segs);
 void __ip_select_ident(struct net *net, struct iphdr *iph, int segs);