From d3aa45ce6b94c65b83971257317867db13e5f492 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 30 Jul 2015 15:36:57 -0700 Subject: bpf: add helpers to access tunnel metadata Introduce helpers to let eBPF programs attached to TC manipulate tunnel metadata: bpf_skb_[gs]et_tunnel_key(skb, key, size, flags) skb: pointer to skb key: pointer to 'struct bpf_tunnel_key' size: size of 'struct bpf_tunnel_key' flags: room for future extensions First eBPF program that uses these helpers will allocate per_cpu metadata_dst structures that will be used on TX. On RX metadata_dst is allocated by tunnel driver. Typical usage for TX: struct bpf_tunnel_key tkey; ... populate tkey ... bpf_skb_set_tunnel_key(skb, &tkey, sizeof(tkey), 0); bpf_clone_redirect(skb, vxlan_dev_ifindex, 0); RX: struct bpf_tunnel_key tkey = {}; bpf_skb_get_tunnel_key(skb, &tkey, sizeof(tkey), 0); ... lookup or redirect based on tkey ... 'struct bpf_tunnel_key' will be extended in the future by adding elements to the end and the 'size' argument will indicate which fields are populated, thereby keeping backwards compatibility. The 'flags' argument may be used as well when the 'size' is not enough or to indicate completely different layout of bpf_tunnel_key. Signed-off-by: Alexei Starovoitov Acked-by: Thomas Graf Signed-off-by: David S. Miller --- include/net/dst_metadata.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include/net/dst_metadata.h') diff --git a/include/net/dst_metadata.h b/include/net/dst_metadata.h index 7b0306894663..075f523ff23f 100644 --- a/include/net/dst_metadata.h +++ b/include/net/dst_metadata.h @@ -51,5 +51,6 @@ static inline bool skb_valid_dst(const struct sk_buff *skb) } struct metadata_dst *metadata_dst_alloc(u8 optslen, gfp_t flags); +struct metadata_dst __percpu *metadata_dst_alloc_percpu(u8 optslen, gfp_t flags); #endif /* __NET_DST_METADATA_H */ -- cgit v1.2.1