diff options
| author | Cong Wang <cong.wang@bytedance.com> | 2021-02-23 21:49:29 +0300 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2021-02-26 23:28:03 +0300 |
| commit | e3526bb92a2084cdaec6cb2855bcec98b280426c (patch) | |
| tree | 8984946e916cdcdb2f4bd2ce606f84dd3ffc7cb9 /include | |
| parent | 16137b09a66f2b75090f1e56a9ba0e27ef845ebc (diff) | |
| download | linux-e3526bb92a2084cdaec6cb2855bcec98b280426c.tar.xz | |
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 <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20210223184934.6054-5-xiyou.wangcong@gmail.com
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/skbuff.h | 3 | ||||
| -rw-r--r-- | include/linux/skmsg.h | 38 | ||||
| -rw-r--r-- | include/net/tcp.h | 19 |
3 files changed, 41 insertions, 19 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 6d0a33d1c0db..bd84f799c952 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -755,6 +755,9 @@ struct sk_buff { void (*destructor)(struct sk_buff *skb); }; struct list_head tcp_tsorted_anchor; +#ifdef CONFIG_NET_SOCK_MSG + unsigned long _sk_redir; +#endif }; #if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE) diff --git a/include/linux/skmsg.h b/include/linux/skmsg.h index 22e26f82de33..e0de45527bb6 100644 --- a/include/linux/skmsg.h +++ b/include/linux/skmsg.h @@ -455,4 +455,42 @@ static inline bool sk_psock_strp_enabled(struct sk_psock *psock) return false; return !!psock->saved_data_ready; } + +#if IS_ENABLED(CONFIG_NET_SOCK_MSG) + +/* We only have one bit so far. */ +#define BPF_F_PTR_MASK ~(BPF_F_INGRESS) + +static inline bool skb_bpf_ingress(const struct sk_buff *skb) +{ + unsigned long sk_redir = skb->_sk_redir; + + return sk_redir & BPF_F_INGRESS; +} + +static inline void skb_bpf_set_ingress(struct sk_buff *skb) +{ + skb->_sk_redir |= BPF_F_INGRESS; +} + +static inline void skb_bpf_set_redir(struct sk_buff *skb, struct sock *sk_redir, + bool ingress) +{ + skb->_sk_redir = (unsigned long)sk_redir; + if (ingress) + skb->_sk_redir |= BPF_F_INGRESS; +} + +static inline struct sock *skb_bpf_redirect_fetch(const struct sk_buff *skb) +{ + unsigned long sk_redir = skb->_sk_redir; + + return (struct sock *)(sk_redir & BPF_F_PTR_MASK); +} + +static inline void skb_bpf_redirect_clear(struct sk_buff *skb) +{ + skb->_sk_redir = 0; +} +#endif /* CONFIG_NET_SOCK_MSG */ #endif /* _LINUX_SKMSG_H */ diff --git a/include/net/tcp.h b/include/net/tcp.h index 947ef5da6867..075de26f449d 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -883,30 +883,11 @@ struct tcp_skb_cb { struct inet6_skb_parm h6; #endif } header; /* For incoming skbs */ - struct { - __u32 flags; - struct sock *sk_redir; - } bpf; }; }; #define TCP_SKB_CB(__skb) ((struct tcp_skb_cb *)&((__skb)->cb[0])) -static inline bool tcp_skb_bpf_ingress(const struct sk_buff *skb) -{ - return TCP_SKB_CB(skb)->bpf.flags & BPF_F_INGRESS; -} - -static inline struct sock *tcp_skb_bpf_redirect_fetch(struct sk_buff *skb) -{ - return TCP_SKB_CB(skb)->bpf.sk_redir; -} - -static inline void tcp_skb_bpf_redirect_clear(struct sk_buff *skb) -{ - TCP_SKB_CB(skb)->bpf.sk_redir = NULL; -} - extern const struct inet_connection_sock_af_ops ipv4_specific; #if IS_ENABLED(CONFIG_IPV6) |