From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.4 required=3.0 tests=DKIMWL_WL_MED,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C7F1CC76194 for ; Thu, 25 Jul 2019 15:33:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id A24F7229F3 for ; Thu, 25 Jul 2019 15:33:53 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="dt7Fyk8+" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389092AbfGYPdw (ORCPT ); Thu, 25 Jul 2019 11:33:52 -0400 Received: from mail-pg1-f202.google.com ([209.85.215.202]:51906 "EHLO mail-pg1-f202.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389058AbfGYPdv (ORCPT ); Thu, 25 Jul 2019 11:33:51 -0400 Received: by mail-pg1-f202.google.com with SMTP id n23so19087490pgf.18 for ; Thu, 25 Jul 2019 08:33:51 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=3XbTWLRwhAiceZDqvAg53SxI5TZhBv0wWnTV5f6ZWpg=; b=dt7Fyk8+3nkOtpq+ABH4X03prQxT2jVZTjXOu26LKAUorYfFXPUtf4Ga4R4An4+QjG nFEeh/gkSzoltiMGhEqQJU59mI9wBqex62CDWTPmY8lslLMqnhD2x1zQRbuZ22pFWjeM N5gipQVPdGvFEAQbEFbgt4KZ0xpzQcnhFNZr/GC8M960zYBoAIKayPZ66FI/KV9TzIDb 7s7ayLv9rkUnQgUr36J5AclM/w83bawrgRsmGIr4te5UZrAE4vrToqnuKZES4WXTfwqm gjLRiC9gtNcCHaN14tnkR72BxE0zidXSBB5uEo2+DQpBMEpWn3m/wR5oAtyyKwK6Y1Lv kcEQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=3XbTWLRwhAiceZDqvAg53SxI5TZhBv0wWnTV5f6ZWpg=; b=ii6Bt+vLOhOOkkyvA8sJnk6mBCIYrVZaGu7enGzKNr5VzCMOkFAISJuGS3LBjzPMuu xMRcB9Lvd/NMc6f1R8f0fXlMzOjrmtub0F0gMj8jBptu3MtXFV46PZKxXOysHyf1hsLp rl/2+759P59THkEF4BGpxii5P8sazIyepPMn2gBvde8V0e+BHUDvBEYmodq1gOpGzHOG cST3aHdsK4DUjKUJiNRd5xHBEqIQYsdLxT1czwkYiMZw1ntOkPsXBgNQdj5/5SiKPZtf hg+wj3TlFdTNZhtNSvZS1Z3B3eCZ/AJdkVyfFBe3RcRnUMxDlue5yUbsuRA/jwyRKRHL IYBg== X-Gm-Message-State: APjAAAUbo9UGvNCyjMA0ogpdn5r7+Z2afUoZzISmrO4mZBcMU3ER6PWU MOveWnQo5AMqIsA+uhAfhPMJG2yTrJ/3gyxMkpjz5IrMshSXQk4IMuJpuPPcOO063fZSMOjYAFm rDz+8ExEkJ0zwhuhkavuzKz4PIKRvarWtazibml6LIVs4PkcxNIofWQ== X-Google-Smtp-Source: APXvYqwLFBkyn38D1qFrEAeYPuAcbFMlbnSs7YTkekejpPm/cNmDJoNnuQp4f4Y9BUhti4M24n36n1c= X-Received: by 2002:a65:6552:: with SMTP id a18mr77689946pgw.208.1564068829986; Thu, 25 Jul 2019 08:33:49 -0700 (PDT) Date: Thu, 25 Jul 2019 08:33:37 -0700 In-Reply-To: <20190725153342.3571-1-sdf@google.com> Message-Id: <20190725153342.3571-3-sdf@google.com> Mime-Version: 1.0 References: <20190725153342.3571-1-sdf@google.com> X-Mailer: git-send-email 2.22.0.657.g960e92d24f-goog Subject: [PATCH bpf-next v2 2/7] bpf/flow_dissector: document flags From: Stanislav Fomichev To: netdev@vger.kernel.org, bpf@vger.kernel.org Cc: davem@davemloft.net, ast@kernel.org, daniel@iogearbox.net, Stanislav Fomichev , Willem de Bruijn , Song Liu , Petar Penkov Content-Type: text/plain; charset="UTF-8" Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Describe what each input flag does and who uses it. Acked-by: Willem de Bruijn Acked-by: Song Liu Cc: Song Liu Cc: Willem de Bruijn Cc: Petar Penkov Signed-off-by: Stanislav Fomichev --- Documentation/bpf/prog_flow_dissector.rst | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/Documentation/bpf/prog_flow_dissector.rst b/Documentation/bpf/prog_flow_dissector.rst index ed343abe541e..0f3f380b2ce4 100644 --- a/Documentation/bpf/prog_flow_dissector.rst +++ b/Documentation/bpf/prog_flow_dissector.rst @@ -26,6 +26,7 @@ and output arguments. * ``nhoff`` - initial offset of the networking header * ``thoff`` - initial offset of the transport header, initialized to nhoff * ``n_proto`` - L3 protocol type, parsed out of L2 header + * ``flags`` - optional flags Flow dissector BPF program should fill out the rest of the ``struct bpf_flow_keys`` fields. Input arguments ``nhoff/thoff/n_proto`` should be @@ -101,6 +102,23 @@ can be called for both cases and would have to be written carefully to handle both cases. +Flags +===== + +``flow_keys->flags`` might contain optional input flags that work as follows: + +* ``FLOW_DISSECTOR_F_PARSE_1ST_FRAG`` - tells BPF flow dissector to continue + parsing first fragment; the default expected behavior is that flow dissector + returns as soon as it finds out that the packet is fragmented; + used by ``eth_get_headlen`` to estimate length of all headers for GRO. +* ``FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL`` - tells BPF flow dissector to stop + parsing as soon as it reaches IPv6 flow label; used by ``___skb_get_hash`` + and ``__skb_get_hash_symmetric`` to get flow hash. +* ``FLOW_DISSECTOR_F_STOP_AT_ENCAP`` - tells BPF flow dissector to stop + parsing as soon as it reaches encapsulated headers; used by routing + infrastructure. + + Reference Implementation ======================== -- 2.22.0.657.g960e92d24f-goog