Re: [PATCH bpf-next v3 5/7] net: remove duplicate sk_lookup helpers

From: Kuniyuki Iwashima
Date: Mon Jun 26 2023 - 16:04:05 EST


From: Lorenz Bauer <lmb@xxxxxxxxxxxxx>
Date: Mon, 26 Jun 2023 16:09:02 +0100
> Now that inet[6]_lookup_reuseport are parameterised on the ehashfn
> we can remove two sk_lookup helpers.
>
> Signed-off-by: Lorenz Bauer <lmb@xxxxxxxxxxxxx>

Reviewed-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxx>


> ---
> include/net/inet6_hashtables.h | 9 +++++++++
> include/net/inet_hashtables.h | 7 +++++++
> net/ipv4/inet_hashtables.c | 26 +++++++++++++-------------
> net/ipv4/udp.c | 32 +++++---------------------------
> net/ipv6/inet6_hashtables.c | 31 ++++++++++++++++---------------
> net/ipv6/udp.c | 34 +++++-----------------------------
> 6 files changed, 55 insertions(+), 84 deletions(-)
>
> diff --git a/include/net/inet6_hashtables.h b/include/net/inet6_hashtables.h
> index 49d586454287..4d2a1a3c0be7 100644
> --- a/include/net/inet6_hashtables.h
> +++ b/include/net/inet6_hashtables.h
> @@ -73,6 +73,15 @@ struct sock *inet6_lookup_listener(struct net *net,
> const unsigned short hnum,
> const int dif, const int sdif);
>
> +struct sock *inet6_lookup_run_sk_lookup(struct net *net,
> + int protocol,
> + struct sk_buff *skb, int doff,
> + const struct in6_addr *saddr,
> + const __be16 sport,
> + const struct in6_addr *daddr,
> + const u16 hnum, const int dif,
> + inet6_ehashfn_t ehashfn);
> +
> static inline struct sock *__inet6_lookup(struct net *net,
> struct inet_hashinfo *hashinfo,
> struct sk_buff *skb, int doff,
> diff --git a/include/net/inet_hashtables.h b/include/net/inet_hashtables.h
> index 51ab6a1a3601..aa02f1db1f86 100644
> --- a/include/net/inet_hashtables.h
> +++ b/include/net/inet_hashtables.h
> @@ -393,6 +393,13 @@ struct sock *inet_lookup_reuseport(struct net *net, struct sock *sk,
> __be32 daddr, unsigned short hnum,
> inet_ehashfn_t ehashfn);
>
> +struct sock *inet_lookup_run_sk_lookup(struct net *net,
> + int protocol,
> + struct sk_buff *skb, int doff,
> + __be32 saddr, __be16 sport,
> + __be32 daddr, u16 hnum, const int dif,
> + inet_ehashfn_t ehashfn);
> +
> static inline struct sock *
> inet_lookup_established(struct net *net, struct inet_hashinfo *hashinfo,
> const __be32 saddr, const __be16 sport,
> diff --git a/net/ipv4/inet_hashtables.c b/net/ipv4/inet_hashtables.c
> index 0dd768ab22d9..34e44a096795 100644
> --- a/net/ipv4/inet_hashtables.c
> +++ b/net/ipv4/inet_hashtables.c
> @@ -405,25 +405,23 @@ static struct sock *inet_lhash2_lookup(struct net *net,
> return result;
> }
>
> -static inline struct sock *inet_lookup_run_bpf(struct net *net,
> - struct inet_hashinfo *hashinfo,
> - struct sk_buff *skb, int doff,
> - __be32 saddr, __be16 sport,
> - __be32 daddr, u16 hnum, const int dif)
> +struct sock *inet_lookup_run_sk_lookup(struct net *net,
> + int protocol,
> + struct sk_buff *skb, int doff,
> + __be32 saddr, __be16 sport,
> + __be32 daddr, u16 hnum, const int dif,
> + inet_ehashfn_t ehashfn)
> {
> struct sock *sk, *reuse_sk;
> bool no_reuseport;
>
> - if (hashinfo != net->ipv4.tcp_death_row.hashinfo)
> - return NULL; /* only TCP is supported */
> -
> - no_reuseport = bpf_sk_lookup_run_v4(net, IPPROTO_TCP, saddr, sport,
> + no_reuseport = bpf_sk_lookup_run_v4(net, protocol, saddr, sport,
> daddr, hnum, dif, &sk);
> if (no_reuseport || IS_ERR_OR_NULL(sk))
> return sk;
>
> reuse_sk = inet_lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum,
> - inet_ehashfn);
> + ehashfn);
> if (reuse_sk)
> sk = reuse_sk;
> return sk;
> @@ -441,9 +439,11 @@ struct sock *__inet_lookup_listener(struct net *net,
> unsigned int hash2;
>
> /* Lookup redirect from BPF */
> - if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
> - result = inet_lookup_run_bpf(net, hashinfo, skb, doff,
> - saddr, sport, daddr, hnum, dif);
> + if (static_branch_unlikely(&bpf_sk_lookup_enabled) &&
> + hashinfo == net->ipv4.tcp_death_row.hashinfo) {
> + result = inet_lookup_run_sk_lookup(net, IPPROTO_TCP, skb, doff,
> + saddr, sport, daddr, hnum, dif,
> + inet_ehashfn);
> if (result)
> goto done;
> }
> diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
> index 7258edece691..eb79268f216d 100644
> --- a/net/ipv4/udp.c
> +++ b/net/ipv4/udp.c
> @@ -464,30 +464,6 @@ static struct sock *udp4_lib_lookup2(struct net *net,
> return result;
> }
>
> -static struct sock *udp4_lookup_run_bpf(struct net *net,
> - struct udp_table *udptable,
> - struct sk_buff *skb,
> - __be32 saddr, __be16 sport,
> - __be32 daddr, u16 hnum, const int dif)
> -{
> - struct sock *sk, *reuse_sk;
> - bool no_reuseport;
> -
> - if (udptable != net->ipv4.udp_table)
> - return NULL; /* only UDP is supported */
> -
> - no_reuseport = bpf_sk_lookup_run_v4(net, IPPROTO_UDP, saddr, sport,
> - daddr, hnum, dif, &sk);
> - if (no_reuseport || IS_ERR_OR_NULL(sk))
> - return sk;
> -
> - reuse_sk = inet_lookup_reuseport(net, sk, skb, sizeof(struct udphdr),
> - saddr, sport, daddr, hnum, udp_ehashfn);
> - if (reuse_sk)
> - sk = reuse_sk;
> - return sk;
> -}
> -
> /* UDP is nearly always wildcards out the wazoo, it makes no sense to try
> * harder than this. -DaveM
> */
> @@ -512,9 +488,11 @@ struct sock *__udp4_lib_lookup(struct net *net, __be32 saddr,
> goto done;
>
> /* Lookup redirect from BPF */
> - if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
> - sk = udp4_lookup_run_bpf(net, udptable, skb,
> - saddr, sport, daddr, hnum, dif);
> + if (static_branch_unlikely(&bpf_sk_lookup_enabled) &&
> + udptable == net->ipv4.udp_table) {
> + sk = inet_lookup_run_sk_lookup(net, IPPROTO_UDP, skb, sizeof(struct udphdr),
> + saddr, sport, daddr, hnum, dif,
> + udp_ehashfn);
> if (sk) {
> result = sk;
> goto done;
> diff --git a/net/ipv6/inet6_hashtables.c b/net/ipv6/inet6_hashtables.c
> index b5de1642bc51..e908aa3cb7ea 100644
> --- a/net/ipv6/inet6_hashtables.c
> +++ b/net/ipv6/inet6_hashtables.c
> @@ -179,31 +179,30 @@ static struct sock *inet6_lhash2_lookup(struct net *net,
> return result;
> }
>
> -static inline struct sock *inet6_lookup_run_bpf(struct net *net,
> - struct inet_hashinfo *hashinfo,
> - struct sk_buff *skb, int doff,
> - const struct in6_addr *saddr,
> - const __be16 sport,
> - const struct in6_addr *daddr,
> - const u16 hnum, const int dif)
> +struct sock *inet6_lookup_run_sk_lookup(struct net *net,
> + int protocol,
> + struct sk_buff *skb, int doff,
> + const struct in6_addr *saddr,
> + const __be16 sport,
> + const struct in6_addr *daddr,
> + const u16 hnum, const int dif,
> + inet6_ehashfn_t ehashfn)
> {
> struct sock *sk, *reuse_sk;
> bool no_reuseport;
>
> - if (hashinfo != net->ipv4.tcp_death_row.hashinfo)
> - return NULL; /* only TCP is supported */
> -
> - no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_TCP, saddr, sport,
> + no_reuseport = bpf_sk_lookup_run_v6(net, protocol, saddr, sport,
> daddr, hnum, dif, &sk);
> if (no_reuseport || IS_ERR_OR_NULL(sk))
> return sk;
>
> reuse_sk = inet6_lookup_reuseport(net, sk, skb, doff,
> - saddr, sport, daddr, hnum, inet6_ehashfn);
> + saddr, sport, daddr, hnum, ehashfn);
> if (reuse_sk)
> sk = reuse_sk;
> return sk;
> }
> +EXPORT_SYMBOL_GPL(inet6_lookup_run_sk_lookup);
>
> struct sock *inet6_lookup_listener(struct net *net,
> struct inet_hashinfo *hashinfo,
> @@ -217,9 +216,11 @@ struct sock *inet6_lookup_listener(struct net *net,
> unsigned int hash2;
>
> /* Lookup redirect from BPF */
> - if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
> - result = inet6_lookup_run_bpf(net, hashinfo, skb, doff,
> - saddr, sport, daddr, hnum, dif);
> + if (static_branch_unlikely(&bpf_sk_lookup_enabled) &&
> + hashinfo == net->ipv4.tcp_death_row.hashinfo) {
> + result = inet6_lookup_run_sk_lookup(net, IPPROTO_TCP, skb, doff,
> + saddr, sport, daddr, hnum, dif,
> + inet6_ehashfn);
> if (result)
> goto done;
> }
> diff --git a/net/ipv6/udp.c b/net/ipv6/udp.c
> index ebac9200b15c..8a6d94cabee0 100644
> --- a/net/ipv6/udp.c
> +++ b/net/ipv6/udp.c
> @@ -205,32 +205,6 @@ static struct sock *udp6_lib_lookup2(struct net *net,
> return result;
> }
>
> -static inline struct sock *udp6_lookup_run_bpf(struct net *net,
> - struct udp_table *udptable,
> - struct sk_buff *skb,
> - const struct in6_addr *saddr,
> - __be16 sport,
> - const struct in6_addr *daddr,
> - u16 hnum, const int dif)
> -{
> - struct sock *sk, *reuse_sk;
> - bool no_reuseport;
> -
> - if (udptable != net->ipv4.udp_table)
> - return NULL; /* only UDP is supported */
> -
> - no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_UDP, saddr, sport,
> - daddr, hnum, dif, &sk);
> - if (no_reuseport || IS_ERR_OR_NULL(sk))
> - return sk;
> -
> - reuse_sk = inet6_lookup_reuseport(net, sk, skb, sizeof(struct udphdr),
> - saddr, sport, daddr, hnum, udp6_ehashfn);
> - if (reuse_sk)
> - sk = reuse_sk;
> - return sk;
> -}
> -
> /* rcu_read_lock() must be held */
> struct sock *__udp6_lib_lookup(struct net *net,
> const struct in6_addr *saddr, __be16 sport,
> @@ -255,9 +229,11 @@ struct sock *__udp6_lib_lookup(struct net *net,
> goto done;
>
> /* Lookup redirect from BPF */
> - if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
> - sk = udp6_lookup_run_bpf(net, udptable, skb,
> - saddr, sport, daddr, hnum, dif);
> + if (static_branch_unlikely(&bpf_sk_lookup_enabled) &&
> + udptable == net->ipv4.udp_table) {
> + sk = inet6_lookup_run_sk_lookup(net, IPPROTO_UDP, skb, sizeof(struct udphdr),
> + saddr, sport, daddr, hnum, dif,
> + udp6_ehashfn);
> if (sk) {
> result = sk;
> goto done;
>
> --
> 2.40.1