On Thu, Aug 25, 2022 at 5:07 PM Kuniyuki Iwashima <kuniyu@xxxxxxxxxx> wrote:
>
> We will soon introduce an optional per-netns ehash.
>
> This means we cannot use the global sk->sk_prot->h.hashinfo
> to fetch a TCP hashinfo.
>
> Instead, set NULL to sk->sk_prot->h.hashinfo for TCP and get
> a proper hashinfo from net->ipv4.tcp_death_row->hashinfo.
>
> Note that we need not use sk->sk_prot->h.hashinfo if DCCP is
> disabled.
>
> Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>
> ---
> include/net/inet_hashtables.h | 10 ++++++++++
> net/ipv4/af_inet.c | 2 +-
> net/ipv4/inet_connection_sock.c | 6 +++---
> net/ipv4/inet_hashtables.c | 14 +++++++-------
> net/ipv4/tcp_ipv4.c | 2 +-
> net/ipv6/tcp_ipv6.c | 2 +-
> 6 files changed, 23 insertions(+), 13 deletions(-)
>
> diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
> index 44a419b9e3d5..2c866112433e 100644
> --- a/include/net/inet_hashtables.h
> +++ b/include/net/inet_hashtables.h
> @@ -170,6 +170,16 @@ struct inet_hashinfo {
> struct inet_listen_hashbucket *lhash2;
> };
>
> +static inline struct inet_hashinfo *inet_get_hashinfo(const struct sock *sk)
> +{
> +#if IS_ENABLED(CONFIG_IP_DCCP)
> + return sk->sk_prot->h.hashinfo ? :
> + sock_net(sk)->ipv4.tcp_death_row->hashinfo;
> +#else
> + return sock_net(sk)->ipv4.tcp_death_row->hashinfo;
> +#endif
> +}
>
If the sk_prot->h.hashinfo must disappear, I would rather add a new
inet->hashinfo field
return inet_sk(sk)->hashinfo
Conceptually, the pointer no longer belongs to sk_prot, and not in struct net,
otherwise you should name this helper tcp_or_dccp_get_hashinfo() to avoid
any temptation to use it for other inet protocol.
