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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT 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 3DA89C43142 for ; Fri, 5 Mar 2021 12:29:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1E61765029 for ; Fri, 5 Mar 2021 12:29:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230301AbhCEM3T (ORCPT ); Fri, 5 Mar 2021 07:29:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:37668 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232143AbhCEM2u (ORCPT ); Fri, 5 Mar 2021 07:28:50 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B059565004; Fri, 5 Mar 2021 12:28:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614947330; bh=JzGixYtf5+BvuzhWznR9rZ5FAYG6cscO50k4x1rw86E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Ynwh9FvRrGu74z1siQY/RcFX7FBz/R21LyQQ3czrmjqaanFEHdW3VTB7iUKajGBmD HjQAdESqIr25tkRzOU0JRaR55qm1Qgm4ThTf/ZGODl7M6i3rqZbfdZARimcoj0M5Om xsgga8Hw8Y7CwsHuo4PZ4cvAgx/Y6P2qgHfaBiOY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Mauri Sandberg , DENG Qingfang , Linus Walleij , "David S. Miller" Subject: [PATCH 5.10 027/102] net: dsa: tag_rtl4_a: Support also egress tags Date: Fri, 5 Mar 2021 13:20:46 +0100 Message-Id: <20210305120904.614493077@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210305120903.276489876@linuxfoundation.org> References: <20210305120903.276489876@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Linus Walleij commit 86dd9868b8788a9063893a97649594af93cd5aa6 upstream. Support also transmitting frames using the custom "8899 A" 4 byte tag. Qingfang came up with the solution: we need to pad the ethernet frame to 60 bytes using eth_skb_pad(), then the switch will happily accept frames with custom tags. Cc: Mauri Sandberg Reported-by: DENG Qingfang Fixes: efd7fe68f0c6 ("net: dsa: tag_rtl4_a: Implement Realtek 4 byte A tag") Signed-off-by: Linus Walleij Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- net/dsa/tag_rtl4_a.c | 43 +++++++++++++++++++++++++++++-------------- 1 file changed, 29 insertions(+), 14 deletions(-) --- a/net/dsa/tag_rtl4_a.c +++ b/net/dsa/tag_rtl4_a.c @@ -12,9 +12,7 @@ * * The 2 bytes tag form a 16 bit big endian word. The exact * meaning has been guessed from packet dumps from ingress - * frames, as no working egress traffic has been available - * we do not know the format of the egress tags or if they - * are even supported. + * frames. */ #include @@ -36,17 +34,34 @@ static struct sk_buff *rtl4a_tag_xmit(struct sk_buff *skb, struct net_device *dev) { - /* - * Just let it pass thru, we don't know if it is possible - * to tag a frame with the 0x8899 ethertype and direct it - * to a specific port, all attempts at reverse-engineering have - * ended up with the frames getting dropped. - * - * The VLAN set-up needs to restrict the frames to the right port. - * - * If you have documentation on the tagging format for RTL8366RB - * (tag type A) then please contribute. - */ + struct dsa_port *dp = dsa_slave_to_port(dev); + u8 *tag; + u16 *p; + u16 out; + + /* Pad out to at least 60 bytes */ + if (unlikely(eth_skb_pad(skb))) + return NULL; + if (skb_cow_head(skb, RTL4_A_HDR_LEN) < 0) + return NULL; + + netdev_dbg(dev, "add realtek tag to package to port %d\n", + dp->index); + skb_push(skb, RTL4_A_HDR_LEN); + + memmove(skb->data, skb->data + RTL4_A_HDR_LEN, 2 * ETH_ALEN); + tag = skb->data + 2 * ETH_ALEN; + + /* Set Ethertype */ + p = (u16 *)tag; + *p = htons(RTL4_A_ETHERTYPE); + + out = (RTL4_A_PROTOCOL_RTL8366RB << 12) | (2 << 8); + /* The lower bits is the port numer */ + out |= (u8)dp->index; + p = (u16 *)(tag + 2); + *p = htons(out); + return skb; }