[PATCH net-next 1/2] lwtunnel: Add destroy state operation
From: Tom Herbert <hidden>
Date: 2016-10-14 01:00:13
Subsystem:
networking [general], networking [ipv4/ipv6], the rest · Maintainers:
"David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, David Ahern, Ido Schimmel, Linus Torvalds
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. Signed-off-by: Tom Herbert <redacted> --- 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..119b11b 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]; };
@@ -43,13 +44,11 @@ struct lwtunnel_encap_ops { int (*get_encap_size)(struct lwtunnel_state *lwtstate); int (*cmp_encap)(struct lwtunnel_state *a, struct lwtunnel_state *b); int (*xmit)(struct sk_buff *skb); + void (*destroy_state)(struct lwtunnel_state *lws); }; #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..7401474 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;
--
2.9.3