bpf: Refactor bpf specific tcp optnames to a new function

The patch moves all bpf specific tcp optnames (TCP_BPF_XXX)
to a new function bpf_sol_tcp_setsockopt().  This will make
the next patch easier to follow.

Reviewed-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/r/20220817061812.4179645-1-kafai@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/net/core/filter.c b/net/core/filter.c
index 6f5bcc8..bb135d4 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -5040,6 +5040,52 @@ static int sol_socket_setsockopt(struct sock *sk, int optname,
                             KERNEL_SOCKPTR(optval), optlen);
 }
 
+static int bpf_sol_tcp_setsockopt(struct sock *sk, int optname,
+                                 char *optval, int optlen)
+{
+       struct tcp_sock *tp = tcp_sk(sk);
+       unsigned long timeout;
+       int val;
+
+       if (optlen != sizeof(int))
+               return -EINVAL;
+
+       val = *(int *)optval;
+
+       /* Only some options are supported */
+       switch (optname) {
+       case TCP_BPF_IW:
+               if (val <= 0 || tp->data_segs_out > tp->syn_data)
+                       return -EINVAL;
+               tcp_snd_cwnd_set(tp, val);
+               break;
+       case TCP_BPF_SNDCWND_CLAMP:
+               if (val <= 0)
+                       return -EINVAL;
+               tp->snd_cwnd_clamp = val;
+               tp->snd_ssthresh = val;
+               break;
+       case TCP_BPF_DELACK_MAX:
+               timeout = usecs_to_jiffies(val);
+               if (timeout > TCP_DELACK_MAX ||
+                   timeout < TCP_TIMEOUT_MIN)
+                       return -EINVAL;
+               inet_csk(sk)->icsk_delack_max = timeout;
+               break;
+       case TCP_BPF_RTO_MIN:
+               timeout = usecs_to_jiffies(val);
+               if (timeout > TCP_RTO_MIN ||
+                   timeout < TCP_TIMEOUT_MIN)
+                       return -EINVAL;
+               inet_csk(sk)->icsk_rto_min = timeout;
+               break;
+       default:
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
 static int __bpf_setsockopt(struct sock *sk, int level, int optname,
                            char *optval, int optlen)
 {
@@ -5094,6 +5140,10 @@ static int __bpf_setsockopt(struct sock *sk, int level, int optname,
                }
        } else if (IS_ENABLED(CONFIG_INET) && level == SOL_TCP &&
                   sk->sk_prot->setsockopt == tcp_setsockopt) {
+               if (optname >= TCP_BPF_IW)
+                       return bpf_sol_tcp_setsockopt(sk, optname,
+                                                     optval, optlen);
+
                if (optname == TCP_CONGESTION) {
                        char name[TCP_CA_NAME_MAX];
 
@@ -5104,7 +5154,6 @@ static int __bpf_setsockopt(struct sock *sk, int level, int optname,
                } else {
                        struct inet_connection_sock *icsk = inet_csk(sk);
                        struct tcp_sock *tp = tcp_sk(sk);
-                       unsigned long timeout;
 
                        if (optlen != sizeof(int))
                                return -EINVAL;
@@ -5112,34 +5161,6 @@ static int __bpf_setsockopt(struct sock *sk, int level, int optname,
                        val = *((int *)optval);
                        /* Only some options are supported */
                        switch (optname) {
-                       case TCP_BPF_IW:
-                               if (val <= 0 || tp->data_segs_out > tp->syn_data)
-                                       ret = -EINVAL;
-                               else
-                                       tcp_snd_cwnd_set(tp, val);
-                               break;
-                       case TCP_BPF_SNDCWND_CLAMP:
-                               if (val <= 0) {
-                                       ret = -EINVAL;
-                               } else {
-                                       tp->snd_cwnd_clamp = val;
-                                       tp->snd_ssthresh = val;
-                               }
-                               break;
-                       case TCP_BPF_DELACK_MAX:
-                               timeout = usecs_to_jiffies(val);
-                               if (timeout > TCP_DELACK_MAX ||
-                                   timeout < TCP_TIMEOUT_MIN)
-                                       return -EINVAL;
-                               inet_csk(sk)->icsk_delack_max = timeout;
-                               break;
-                       case TCP_BPF_RTO_MIN:
-                               timeout = usecs_to_jiffies(val);
-                               if (timeout > TCP_RTO_MIN ||
-                                   timeout < TCP_TIMEOUT_MIN)
-                                       return -EINVAL;
-                               inet_csk(sk)->icsk_rto_min = timeout;
-                               break;
                        case TCP_SAVE_SYN:
                                if (val < 0 || val > 1)
                                        ret = -EINVAL;