From e3526bb92a2084cdaec6cb2855bcec98b280426c Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Tue, 23 Feb 2021 10:49:29 -0800 Subject: skmsg: Move sk_redir from TCP_SKB_CB to skb Currently TCP_SKB_CB() is hard-coded in skmsg code, it certainly does not work for any other non-TCP protocols. We can move them to skb ext, but it introduces a memory allocation on fast path. Fortunately, we only need to a word-size to store all the information, because the flags actually only contains 1 bit so can be just packed into the lowest bit of the "pointer", which is stored as unsigned long. Inside struct sk_buff, '_skb_refdst' can be reused because skb dst is no longer needed after ->sk_data_ready() so we can just drop it. Signed-off-by: Cong Wang Signed-off-by: Alexei Starovoitov Acked-by: John Fastabend Acked-by: Jakub Sitnicki Link: https://lore.kernel.org/bpf/20210223184934.6054-5-xiyou.wangcong@gmail.com --- net/core/sock_map.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-) (limited to 'net/core/sock_map.c') diff --git a/net/core/sock_map.c b/net/core/sock_map.c index 1a28a5c2c61e..dbfcd7006338 100644 --- a/net/core/sock_map.c +++ b/net/core/sock_map.c @@ -657,7 +657,6 @@ const struct bpf_func_proto bpf_sock_map_update_proto = { BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb, struct bpf_map *, map, u32, key, u64, flags) { - struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); struct sock *sk; if (unlikely(flags & ~(BPF_F_INGRESS))) @@ -667,8 +666,7 @@ BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb, if (unlikely(!sk || !sock_map_redirect_allowed(sk))) return SK_DROP; - tcb->bpf.flags = flags; - tcb->bpf.sk_redir = sk; + skb_bpf_set_redir(skb, sk, flags & BPF_F_INGRESS); return SK_PASS; } @@ -1250,7 +1248,6 @@ const struct bpf_func_proto bpf_sock_hash_update_proto = { BPF_CALL_4(bpf_sk_redirect_hash, struct sk_buff *, skb, struct bpf_map *, map, void *, key, u64, flags) { - struct tcp_skb_cb *tcb = TCP_SKB_CB(skb); struct sock *sk; if (unlikely(flags & ~(BPF_F_INGRESS))) @@ -1260,8 +1257,7 @@ BPF_CALL_4(bpf_sk_redirect_hash, struct sk_buff *, skb, if (unlikely(!sk || !sock_map_redirect_allowed(sk))) return SK_DROP; - tcb->bpf.flags = flags; - tcb->bpf.sk_redir = sk; + skb_bpf_set_redir(skb, sk, flags & BPF_F_INGRESS); return SK_PASS; } -- cgit v1.2.3