inet: Hide route peer accesses behind helpers.

We encode the pointer(s) into an unsigned long with one state bit.

The state bit is used so we can store the inetpeer tree root to use
when resolving the peer later.

Later the peer roots will be per-FIB table, and this change works to
facilitate that.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 38 insertions, 4 deletions

diff --git a/include/net/route.h b/include/net/route.h
index 433fc6c..6340c37 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -67,10 +67,44 @@ struct rtable {
 	/* Miscellaneous cached information */
 	__be32			rt_spec_dst; /* RFC1122 specific destination */
 	u32			rt_peer_genid;
-	struct inet_peer	*peer; /* long-living peer info */
+	unsigned long		_peer; /* long-living peer info */
 	struct fib_info		*fi; /* for client ref to shared metrics */
 };
 
+static inline struct inet_peer *rt_peer_ptr(struct rtable *rt)
+{
+	return inetpeer_ptr(rt->_peer);
+}
+
+static inline bool rt_has_peer(struct rtable *rt)
+{
+	return inetpeer_ptr_is_peer(rt->_peer);
+}
+
+static inline void __rt_set_peer(struct rtable *rt, struct inet_peer *peer)
+{
+	__inetpeer_ptr_set_peer(&rt->_peer, peer);
+}
+
+static inline bool rt_set_peer(struct rtable *rt, struct inet_peer *peer)
+{
+	return inetpeer_ptr_set_peer(&rt->_peer, peer);
+}
+
+static inline void rt_init_peer(struct rtable *rt, struct inet_peer_base *base)
+{
+	inetpeer_init_ptr(&rt->_peer, base);
+}
+
+static inline void rt_transfer_peer(struct rtable *rt, struct rtable *ort)
+{
+	rt->_peer = ort->_peer;
+	if (rt_has_peer(ort)) {
+		struct inet_peer *peer = rt_peer_ptr(ort);
+		atomic_inc(&peer->refcnt);
+	}
+}
+
 static inline bool rt_is_input_route(const struct rtable *rt)
 {
 	return rt->rt_route_iif != 0;
@@ -298,11 +332,11 @@ extern void rt_bind_peer(struct rtable *rt, __be32 daddr, int create);
 
 static inline struct inet_peer *__rt_get_peer(struct rtable *rt, __be32 daddr, int create)
 {
-	if (rt->peer)
-		return rt->peer;
+	if (rt_has_peer(rt))
+		return rt_peer_ptr(rt);
 
 	rt_bind_peer(rt, daddr, create);
-	return rt->peer;
+	return rt_peer_ptr(rt);
 }
 
 static inline struct inet_peer *rt_get_peer(struct rtable *rt, __be32 daddr)