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=-9.5 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,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C8FF3C433DB for ; Thu, 11 Feb 2021 04:19:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75CBA64DCD for ; Thu, 11 Feb 2021 04:19:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229741AbhBKETT (ORCPT ); Wed, 10 Feb 2021 23:19:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50884 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229577AbhBKETM (ORCPT ); Wed, 10 Feb 2021 23:19:12 -0500 Received: from mail-pg1-x52f.google.com (mail-pg1-x52f.google.com [IPv6:2607:f8b0:4864:20::52f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1EA0AC061574; Wed, 10 Feb 2021 20:18:32 -0800 (PST) Received: by mail-pg1-x52f.google.com with SMTP id b21so2944367pgk.7; Wed, 10 Feb 2021 20:18:32 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=ySQs/bUrDiTXrbAw1rcoAwSp8NINSHA8BKI1E9gDSMc=; b=ZPgTOhUWUmB14eeEZokD8KQf4APDXMsP7Bm7zcBbwWSKmhHylXKsVx0ilbDaGF32sr 4Pnyx6vpgzo6qXW8cJD1mUkICvbD0dU8GPhFDIQTCpvr3UbkvdIjqAd7KGn7fwt0xbKv fMvL6VBhrW077N/ocwMZEkwT5E2jUZ4ag29qCubKsuiEpg3XXJQPPBP7DP40sOoMBWSg LudXJQp6xgApRIy6TMo0MCojoSF7TNrrHBiTfxu8liMTFHfP/ytQegEKfrz0YqErPKf2 dKAvcvx6PHS5F7VRB3aJwEbgf1B1p7oMxQ+vdsl7sBhRIhAAj83j8RDk0rPinI4oBWBw oV9Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=ySQs/bUrDiTXrbAw1rcoAwSp8NINSHA8BKI1E9gDSMc=; b=eNHTCI6IChrmy0hmuaetTKc1f8X0kgZNwkHu0/Mry/c9HcsdmKArNgjCUyUz3hsed9 Pnt3zuy0PgEWVeCmPFQGaItgosZkpHp110RRbNvVRNRfPscCx1eeo4z+r0JkpyE75Klm oI+HxGFJqkRA08IbnfS3F7OcbvErgkmwHt7KCOzRTCcin7JkQ+qIcN5y9cvR6oUPKnBO 6peHhoPMzOXQ+O3nmKda3/KBrLpCDXXXBLybhreodjhGSFO02RBadGis9kLCNglOQtpE uCU7TutNBVuGFdcZV5ot2xCnVbCeNlp0+vfmn5oyEwXEM6/eGmEN4B7u4B/7wx5+63JJ OyIQ== X-Gm-Message-State: AOAM533UbUmNz1lC2hYA1MM2UuUJ95Boyl76fByVA/whfnpWtoTrImjl 0MfFnekyk++SXhBwyT1x2u2ofbDdKkE= X-Google-Smtp-Source: ABdhPJweA9TAWgNsC+Ig6uguW2ukgU/fDQnLgu0DQrTuXlMNVLDFdbWKH9OObUxGnBh8rlGcZnDPbw== X-Received: by 2002:a05:6a00:23c5:b029:1e6:2f2e:a438 with SMTP id g5-20020a056a0023c5b02901e62f2ea438mr2823786pfc.75.1613017111220; Wed, 10 Feb 2021 20:18:31 -0800 (PST) Received: from [10.230.29.30] ([192.19.223.252]) by smtp.gmail.com with ESMTPSA id t6sm3716349pgp.57.2021.02.10.20.18.28 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 10 Feb 2021 20:18:30 -0800 (PST) Subject: Re: [PATCH v3 net-next 06/11] net: dsa: kill .port_egress_floods overengineering To: Vladimir Oltean , Jakub Kicinski , "David S. Miller" Cc: Andrew Lunn , Vivien Didelot , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bridge@lists.linux-foundation.org, Roopa Prabhu , Nikolay Aleksandrov , Jiri Pirko , Ido Schimmel , Claudiu Manoil , Alexandre Belloni , UNGLinuxDriver@microchip.com, Vadym Kochan , Taras Chornyi , Grygorii Strashko , Ioana Ciornei , Ivan Vecera , linux-omap@vger.kernel.org References: <20210210091445.741269-1-olteanv@gmail.com> <20210210091445.741269-7-olteanv@gmail.com> From: Florian Fainelli Message-ID: Date: Wed, 10 Feb 2021 20:18:27 -0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Firefox/78.0 Thunderbird/78.7.1 MIME-Version: 1.0 In-Reply-To: <20210210091445.741269-7-olteanv@gmail.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-omap@vger.kernel.org On 2/10/2021 1:14 AM, Vladimir Oltean wrote: > From: Vladimir Oltean > > The bridge offloads the port flags through a single bit mask using > switchdev, which among others, contains learning and flooding settings. > > The commit 57652796aa97 ("net: dsa: add support for bridge flags") > missed one crucial aspect of the SWITCHDEV_ATTR_ID_PORT_BRIDGE_FLAGS API > when designing the API one level lower, towards the drivers. > This is that the bitmask of passed brport flags never has more than one > bit set at a time. On the other hand, the prototype passed to the driver > is .port_egress_floods(int port, bool unicast, bool multicast), which > configures two flags at a time. > > DSA currently checks if .port_egress_floods is implemented, and if it > is, reports both BR_FLOOD and BR_MCAST_FLOOD as supported. So the driver > has no choice if it wants to inform the bridge that, for example, it > can't configure unicast flooding independently of multicast flooding - > the DSA mid layer is standing in the way. Or the other way around: a new > driver wants to start configuring BR_BCAST_FLOOD separately, but what do > we do with the rest, which only support unicast and multicast flooding? > Do we report broadcast flooding configuration as supported for those > too, and silently do nothing? > > Secondly, currently DSA deems the driver too dumb to deserve knowing that > a SWITCHDEV_ATTR_ID_BRIDGE_MROUTER attribute was offloaded, because it > just calls .port_egress_floods for the CPU port. When we'll add support > for the plain SWITCHDEV_ATTR_ID_PORT_MROUTER, that will become a real > problem because the flood settings will need to be held statefully in > the DSA middle layer, otherwise changing the mrouter port attribute will > impact the flooding attribute. And that's _assuming_ that the underlying > hardware doesn't have anything else to do when a multicast router > attaches to a port than flood unknown traffic to it. If it does, there > will need to be a dedicated .port_set_mrouter anyway. > > Lastly, we have DSA drivers that have a backlink into a pure switchdev > driver (felix -> ocelot). It seems reasonable that the other switchdev > drivers should not have to suffer from the oddities of DSA overengineering, > so keeping DSA a pass-through layer makes more sense there. > > To simplify the brport flags situation we just delete .port_egress_floods > and we introduce a simple .port_bridge_flags which is passed to the > driver. Also, the logic from dsa_port_mrouter is removed and a > .port_set_mrouter is created. > > Functionally speaking, we simply move the calls to .port_egress_floods > one step lower, in the two drivers that implement it: mv88e6xxx and b53, > so things should work just as before. > > Signed-off-by: Vladimir Oltean Reviewed-by: Florian Fainelli -- Florian