ip_tunnel: Preserve pointer const in ip_tunnel_info_opts

Change ip_tunnel_info_opts( ) from static function to macro to cast return
value and preserve the const-ness of the pointer.

Signed-off-by: Gavin Li <gavinl@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/include/net/ip_tunnels.h b/include/net/ip_tunnels.h
index fca3576..255b32a 100644 (file)
--- a/include/net/ip_tunnels.h
+++ b/include/net/ip_tunnels.h
@@ -67,6 +67,12 @@ struct ip_tunnel_key {
        GENMASK((sizeof_field(struct ip_tunnel_info,            \
                              options_len) * BITS_PER_BYTE) - 1, 0)
 
+#define ip_tunnel_info_opts(info)                              \
+       _Generic(info,                                          \
+                const struct ip_tunnel_info * : ((const void *)((info) + 1)),\
+                struct ip_tunnel_info * : ((void *)((info) + 1))\
+       )
+
 struct ip_tunnel_info {
        struct ip_tunnel_key    key;
 #ifdef CONFIG_DST_CACHE
@@ -485,11 +491,6 @@ static inline void iptunnel_xmit_stats(struct net_device *dev, int pkt_len)
        }
 }
 
-static inline void *ip_tunnel_info_opts(struct ip_tunnel_info *info)
-{
-       return info + 1;
-}
-
 static inline void ip_tunnel_info_opts_get(void *to,
                                           const struct ip_tunnel_info *info)
 {