From patchwork Sun Feb 21 21:33:51 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Vladimir Oltean X-Patchwork-Id: 386097 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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 0A007C433DB for ; Sun, 21 Feb 2021 21:36:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D6E5864EBE for ; Sun, 21 Feb 2021 21:36:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231238AbhBUVgc (ORCPT ); Sun, 21 Feb 2021 16:36:32 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40156 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231190AbhBUVff (ORCPT ); Sun, 21 Feb 2021 16:35:35 -0500 Received: from mail-ed1-x535.google.com (mail-ed1-x535.google.com [IPv6:2a00:1450:4864:20::535]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AFCA3C0617A9 for ; Sun, 21 Feb 2021 13:34:14 -0800 (PST) Received: by mail-ed1-x535.google.com with SMTP id h25so5862654eds.4 for ; Sun, 21 Feb 2021 13:34:14 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=2zYyNpPOqLqu4fXlOOuGHHQD2qu3Ha8IhbOXBQeShV4=; b=VzaSuO2QsW1UiNl+ZpK9L6Z9bZ7jcUh98PdbEG4QIYk25P3hFTei55T/jk3W77a+pP /NMufkFgvxJEfP2bqhgezF5iOzgGr2zcKrCZFVTia/JatFvOQfqAU5Noi8j0BOkaAU8n 2HCV/qSUroabwAEqzVTNPAJAJ1+G8ox5nT6jdisiRoowqArxGtvyOxakPnsG/G+WzwYe MWHgSKiz82fzBzWg9h7Hp4qFP/f4qBqVvVDwJYZnIUek2bQiCHwsj8oLoGHy0PpVRKUx kzGn8doIBLTyXZ8gQppK3sym4s2Y5dXdZRb91wSkazfCPGzrsWmCOKir4BQ8G7CV+eCV zWbw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=2zYyNpPOqLqu4fXlOOuGHHQD2qu3Ha8IhbOXBQeShV4=; b=mWX+wULVWmwHdkDUq9vA8jmzeYCanKUeA9jUhXmifp+45SQf6BQQoOIGQsbhrY1Bnc 6dqu3GfntKEDfVoGoBKg9M7n1xmZFmtVpiLAJPThyQm2fUifXHAqfNwcXlFvdJ78MN+V FNFfkAemHSVNHu0SqD0uzDYVftH+pfSrsw9Xxc5Lb+bbdg9dlz6JJhP4Fy0NWCDC2C1G edGJLElWJ3dn+99Ig++X7VXw/xMxKSfr07kpMPQzTYPR2RXPTHeUIn8pr6Nyq+kQGsuy RddR7v4DK/ARmsiBmgQHcptGt/Ne5O51FCDAXQElpjir/VCL+qWcidUVM80Qz6a1nk08 lTtg== X-Gm-Message-State: AOAM532jz0RP18upeNOqiiiFXaRIxLJzX2HaPC1HHJXaSH+X4Qg5jv0t mtxLZxlGl8iq6wnj22Qzf1OjzkufYlw= X-Google-Smtp-Source: ABdhPJzifpBckF8vS+8jERH6Te6TkN+0X8pRB6bmuRSkyuFvDQTq4Eno6m2VxR849ZTKWiI/jd5yxQ== X-Received: by 2002:a50:da8b:: with SMTP id q11mr20010466edj.352.1613943253205; Sun, 21 Feb 2021 13:34:13 -0800 (PST) Received: from localhost.localdomain ([188.25.217.13]) by smtp.gmail.com with ESMTPSA id rh22sm8948779ejb.105.2021.02.21.13.34.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 21 Feb 2021 13:34:12 -0800 (PST) From: Vladimir Oltean To: netdev@vger.kernel.org Cc: Andrew Lunn , Florian Fainelli , Vivien Didelot , Jiri Pirko , Ido Schimmel , DENG Qingfang , Tobias Waldekranz , George McCollister , Horatiu Vultur , Kurt Kanzenbach Subject: [RFC PATCH net-next 08/12] Documentation: networking: dsa: add paragraph for the LAG offload Date: Sun, 21 Feb 2021 23:33:51 +0200 Message-Id: <20210221213355.1241450-9-olteanv@gmail.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20210221213355.1241450-1-olteanv@gmail.com> References: <20210221213355.1241450-1-olteanv@gmail.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Vladimir Oltean Add a short summary of the methods that a driver writer must implement for offloading a link aggregation group, and what is still missing. Cc: Tobias Waldekranz Signed-off-by: Vladimir Oltean --- Documentation/networking/dsa/dsa.rst | 32 ++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/Documentation/networking/dsa/dsa.rst b/Documentation/networking/dsa/dsa.rst index 463b48714fe9..0a5b06cf4d45 100644 --- a/Documentation/networking/dsa/dsa.rst +++ b/Documentation/networking/dsa/dsa.rst @@ -698,6 +698,38 @@ Bridge VLAN filtering function that the driver has to call for each MAC address known to be behind the given port. A switchdev object is used to carry the VID and MDB info. +Link aggregation +---------------- + +Link aggregation is implemented in the Linux networking stack by the bonding +and team drivers, which are modeled as virtual, stackable network interfaces. +DSA is capable of offloading a link aggregation group (LAG) to hardware that +supports the feature, and supports bridging between physical ports and LAGs, +as well as between LAGs. A bonding/team interface which holds multiple physical +ports constitutes a logical port, although DSA has no explicit concept of a +physical port at the moment. Due to this, events where a LAG joins/leaves a +bridge are treated as if all individual physical ports that are members of that +LAG join/leave the bridge. Switchdev port attributes (VLAN filtering, STP +state, etc) on a LAG are treated similarly: DSA offloads the same switchdev +port attribute on all members of the LAG. Switchdev objects on a LAG (FDB, MDB) +are not yet supported, since the DSA driver API does not have the concept of a +logical port ID. + +- ``port_lag_join``: function invoked when a given switch port is added to a + LAG. The driver may return ``-EOPNOTSUPP``, and in this case, DSA will fall + back to a software implementation where all traffic from this port is sent to + the CPU. +- ``port_lag_leave``: function invoked when a given switch port leaves a LAG + and returns to operation as a standalone port. +- ``port_lag_change``: function invoked when the link state of any member of + the LAG changes, and the hashing function needs rebalancing only towards the + subset of physical LAG member ports that are up. + +Drivers that benefit from having an ID associated with each offloaded LAG +can optionally populate ``ds->num_lag_ids`` from the ``dsa_switch_ops::setup`` +method. The LAG ID associated with a bonding/team interface can then be +retrieved by a DSA switch driver using the ``dsa_lag_id`` function. + TODO ====