net: lwtunnel: Handle fragmentation

[cascardo/linux.git] / include / net / lwtunnel.h

diff --git a/include/net/lwtunnel.h b/include/net/lwtunnel.h
index e9f116e..ea3f80f 100644 (file)
--- a/include/net/lwtunnel.h
+++ b/include/net/lwtunnel.h
@@ -13,6 +13,13 @@
 /* lw tunnel state flags */
 #define LWTUNNEL_STATE_OUTPUT_REDIRECT BIT(0)
 #define LWTUNNEL_STATE_INPUT_REDIRECT  BIT(1)
+#define LWTUNNEL_STATE_XMIT_REDIRECT   BIT(2)
+
+enum {
+       LWTUNNEL_XMIT_DONE,
+       LWTUNNEL_XMIT_CONTINUE,
+};
+
 
 struct lwtunnel_state {
        __u16           type;
@@ -21,6 +28,7 @@ struct lwtunnel_state {
        int             (*orig_output)(struct net *net, struct sock *sk, struct sk_buff *skb);
        int             (*orig_input)(struct sk_buff *);
        int             len;
+       __u16           headroom;
        __u8            data[0];
 };
 
@@ -34,6 +42,7 @@ struct lwtunnel_encap_ops {
                          struct lwtunnel_state *lwtstate);
        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);
 };
 
 #ifdef CONFIG_LWTUNNEL
@@ -75,6 +84,24 @@ static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
 
        return false;
 }
+
+static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
+{
+       if (lwtstate && (lwtstate->flags & LWTUNNEL_STATE_XMIT_REDIRECT))
+               return true;
+
+       return false;
+}
+
+static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
+                                            unsigned int mtu)
+{
+       if (lwtunnel_xmit_redirect(lwtstate) && lwtstate->headroom < mtu)
+               return lwtstate->headroom;
+
+       return 0;
+}
+
 int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
                           unsigned int num);
 int lwtunnel_encap_del_ops(const struct lwtunnel_encap_ops *op,
@@ -90,6 +117,7 @@ struct lwtunnel_state *lwtunnel_state_alloc(int hdr_len);
 int lwtunnel_cmp_encap(struct lwtunnel_state *a, struct lwtunnel_state *b);
 int lwtunnel_output(struct net *net, struct sock *sk, struct sk_buff *skb);
 int lwtunnel_input(struct sk_buff *skb);
+int lwtunnel_xmit(struct sk_buff *skb);
 
 #else
 
@@ -117,6 +145,17 @@ static inline bool lwtunnel_input_redirect(struct lwtunnel_state *lwtstate)
        return false;
 }
 
+static inline bool lwtunnel_xmit_redirect(struct lwtunnel_state *lwtstate)
+{
+       return false;
+}
+
+static inline unsigned int lwtunnel_headroom(struct lwtunnel_state *lwtstate,
+                                            unsigned int mtu)
+{
+       return 0;
+}
+
 static inline int lwtunnel_encap_add_ops(const struct lwtunnel_encap_ops *op,
                                         unsigned int num)
 {
@@ -170,6 +209,11 @@ static inline int lwtunnel_input(struct sk_buff *skb)
        return -EOPNOTSUPP;
 }
 
+static inline int lwtunnel_xmit(struct sk_buff *skb)
+{
+       return -EOPNOTSUPP;
+}
+
 #endif /* CONFIG_LWTUNNEL */
 
 #define MODULE_ALIAS_RTNL_LWT(encap_type) MODULE_ALIAS("rtnl-lwt-" __stringify(encap_type))