From 1104d9ba443a3972052ea4eaa01e51f9ee084652 Mon Sep 17 00:00:00 2001 From: Tom Herbert Date: Fri, 14 Oct 2016 11:25:36 -0700 Subject: [PATCH] lwtunnel: Add destroy state operation Users of lwt tunnels may set up some secondary state in build_state function. Add a corresponding destroy_state function to allow users to clean up state. This destroy state function is called from lwstate_free. Also, we now free lwstate using kfree_rcu so user can assume structure is not freed before rcu. Acked-by: Roopa Prabhu Signed-off-by: Tom Herbert Signed-off-by: David S. Miller --- include/net/lwtunnel.h | 7 +++---- net/core/lwtunnel.c | 13 +++++++++++++ 2 files changed, 16 insertions(+), 4 deletions(-) diff --git a/include/net/lwtunnel.h b/include/net/lwtunnel.h index ea3f80f..67d235f 100644 --- a/include/net/lwtunnel.h +++ b/include/net/lwtunnel.h @@ -29,6 +29,7 @@ struct lwtunnel_state { int (*orig_input)(struct sk_buff *); int len; __u16 headroom; + struct rcu_head rcu; __u8 data[0]; }; @@ -36,6 +37,7 @@ struct lwtunnel_encap_ops { int (*build_state)(struct net_device *dev, struct nlattr *encap, unsigned int family, const void *cfg, struct lwtunnel_state **ts); + void (*destroy_state)(struct lwtunnel_state *lws); int (*output)(struct net *net, struct sock *sk, struct sk_buff *skb); int (*input)(struct sk_buff *skb); int (*fill_encap)(struct sk_buff *skb, @@ -46,10 +48,7 @@ struct lwtunnel_encap_ops { }; #ifdef CONFIG_LWTUNNEL -static inline void lwtstate_free(struct lwtunnel_state *lws) -{ - kfree(lws); -} +void lwtstate_free(struct lwtunnel_state *lws); static inline struct lwtunnel_state * lwtstate_get(struct lwtunnel_state *lws) diff --git a/net/core/lwtunnel.c b/net/core/lwtunnel.c index e5f84c2..88fd642 100644 --- a/net/core/lwtunnel.c +++ b/net/core/lwtunnel.c @@ -130,6 +130,19 @@ int lwtunnel_build_state(struct net_device *dev, u16 encap_type, } EXPORT_SYMBOL(lwtunnel_build_state); +void lwtstate_free(struct lwtunnel_state *lws) +{ + const struct lwtunnel_encap_ops *ops = lwtun_encaps[lws->type]; + + if (ops->destroy_state) { + ops->destroy_state(lws); + kfree_rcu(lws, rcu); + } else { + kfree(lws); + } +} +EXPORT_SYMBOL(lwtstate_free); + int lwtunnel_fill_encap(struct sk_buff *skb, struct lwtunnel_state *lwtstate) { const struct lwtunnel_encap_ops *ops; -- 2.7.4