neigh: Create mechanism for generic neigh private areas.

The implementation private sits right after the primary_key memory.

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

1 files changed, 7 insertions, 0 deletions

diff --git a/include/net/neighbour.h b/include/net/neighbour.h
index 7ae5acff96e..87c0e5ce649 100644
--- a/include/net/neighbour.h
+++ b/include/net/neighbour.h
@@ -179,6 +179,13 @@ struct neigh_table {
         struct pneigh_entry     **phash_buckets;
 };
 
+#define NEIGH_PRIV_ALIGN        sizeof(long long)
+
+static inline void *neighbour_priv(const struct neighbour *n)
+{
+        return (char *)n + ALIGN(sizeof(*n) + n->tbl->key_len, NEIGH_PRIV_ALIGN);
+}
+
 /* flags for neigh_update() */
 #define NEIGH_UPDATE_F_OVERRIDE                 0x00000001
 #define NEIGH_UPDATE_F_WEAK_OVERRIDE            0x00000002