diff options
| author | Prankur gupta <prankgup@fb.com> | 2020-12-02 13:31:51 -0800 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2020-12-03 17:23:24 -0800 |
| commit | cb81110997d1f5097f29dd8e49d32a1fc55cbf86 (patch) | |
| tree | 9e4266c79d35395cbccd79f7eb7cf4c27eaef2b9 /net/ipv4 | |
| parent | 2faa7328f53b36b2b171501154bba3fd66d8f5da (diff) | |
bpf: Adds support for setting window clamp
Adds a new bpf_setsockopt for TCP sockets, TCP_BPF_WINDOW_CLAMP,
which sets the maximum receiver window size. It will be useful for
limiting receiver window based on RTT.
Signed-off-by: Prankur gupta <prankgup@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20201202213152.435886-2-prankgup@fb.com
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp.c | 25 |
1 files changed, 16 insertions, 9 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index b2bc3d7fe9e8..17379f6dd955 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -3022,6 +3022,21 @@ int tcp_sock_set_keepcnt(struct sock *sk, int val) } EXPORT_SYMBOL(tcp_sock_set_keepcnt); +int tcp_set_window_clamp(struct sock *sk, int val) +{ + struct tcp_sock *tp = tcp_sk(sk); + + if (!val) { + if (sk->sk_state != TCP_CLOSE) + return -EINVAL; + tp->window_clamp = 0; + } else { + tp->window_clamp = val < SOCK_MIN_RCVBUF / 2 ? + SOCK_MIN_RCVBUF / 2 : val; + } + return 0; +} + /* * Socket option code for TCP. */ @@ -3235,15 +3250,7 @@ static int do_tcp_setsockopt(struct sock *sk, int level, int optname, break; case TCP_WINDOW_CLAMP: - if (!val) { - if (sk->sk_state != TCP_CLOSE) { - err = -EINVAL; - break; - } - tp->window_clamp = 0; - } else - tp->window_clamp = val < SOCK_MIN_RCVBUF / 2 ? - SOCK_MIN_RCVBUF / 2 : val; + err = tcp_set_window_clamp(sk, val); break; case TCP_QUICKACK: |