From patchwork Thu Jun 10 17:44:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Loic Poulain X-Patchwork-Id: 12313647 X-Patchwork-Delegate: kuba@kernel.org 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,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=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 ACBDCC47094 for ; Thu, 10 Jun 2021 17:35:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 92B1D613E1 for ; Thu, 10 Jun 2021 17:35:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231243AbhFJRhb (ORCPT ); Thu, 10 Jun 2021 13:37:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59150 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230502AbhFJRhX (ORCPT ); Thu, 10 Jun 2021 13:37:23 -0400 Received: from mail-wr1-x429.google.com (mail-wr1-x429.google.com [IPv6:2a00:1450:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 473DDC0617A6 for ; Thu, 10 Jun 2021 10:35:11 -0700 (PDT) Received: by mail-wr1-x429.google.com with SMTP id l2so3229290wrw.6 for ; Thu, 10 Jun 2021 10:35:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=Ex6KOBRtY39MKOv6zeVS81/i8ZlR1DGsMXXweuEIq84=; b=pGA1/Eq/WGWaNPAx1bjvjqyeipVuB31JeFcZ0QfM/SmzE82xFGrXzZCtCMU0STDRTL 8/UUxU9dezCJIjvL9/s9/vfw/4TVVnRapofJ7EXAJbAa+ZzQRBnQJOCoe0JcSN4m8xNK rD7Jjo+hfmViXl8WTJJtR+6Ms7KMxVDz8mTIBieambYtSxpgBQMi+aiu57lRqZTuHC+v reiWg0C2lRQ0rEe/315P6rdgbCsZd+/gGjcvH9VKjkRhIjBhyk8CeiiSXRhuxLbfcw2w hREkCjku3xX6zrlwVZzftQMu7pqoMtNBhxgBp9BRRnh/fKSaCNCxMejgvwpQFkMS/899 YoMg== 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; bh=Ex6KOBRtY39MKOv6zeVS81/i8ZlR1DGsMXXweuEIq84=; b=h731sKz28yEfp9zqPbLnxyMeV09Afgyl4NM8aJYrx9fTaNSKd/RCgIG5qgI0tDTxkA BI6v2/B/lsGUYEMV4QPuvkMW+JlD8qOvz1tO/3UDwx99Kg7OYYFS7vV7yCdPsT/hGFWh nJBFgFg4w0naFOEKznNOdGX74vlISGF7bhmy+wWeZkZdgPeTPL1DleP4ORZM5mh1KQhZ yjffaERpXIt++PnMJc8C4xWxrL1CJ+zWHWJo3HAinj48tXvmmahTuZ9WMnK31uucFK/F AJ5Y649wxgybRgU6XnCt2pdPH6OD2oj7Eyj5I9s3uNDALSF45J6GDsNVjdB/vWWu8od2 4yrw== X-Gm-Message-State: AOAM530hWYhdtKwFMWqLeejLim8VX800MplMxyeha5fp6HhASyugyzjH 6jAWy4/TUT/2faxBVYtBPikdqg== X-Google-Smtp-Source: ABdhPJyBIT3F5KAger2RGNqQSCfi/Z6cPD3EbD8fcS3M7xBR3eEo8EDBO5DWEo2LRgVNnLjUprc/xA== X-Received: by 2002:adf:df8a:: with SMTP id z10mr7171736wrl.62.1623346509769; Thu, 10 Jun 2021 10:35:09 -0700 (PDT) Received: from localhost.localdomain ([2a01:e0a:82c:5f0:85ed:406e:1bc4:a268]) by smtp.gmail.com with ESMTPSA id x3sm9921356wmj.30.2021.06.10.10.35.08 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Thu, 10 Jun 2021 10:35:09 -0700 (PDT) From: Loic Poulain To: kuba@kernel.org, davem@davemloft.net Cc: netdev@vger.kernel.org, johannes.berg@intel.com, leon@kernel.org, m.chetan.kumar@intel.com, parav@nvidia.com, Sergey Ryazanov , Loic Poulain Subject: [PATCH net-next v2 2/3] rtnetlink: add IFLA_PARENT_[DEV|DEV_BUS]_NAME Date: Thu, 10 Jun 2021 19:44:48 +0200 Message-Id: <1623347089-28788-2-git-send-email-loic.poulain@linaro.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1623347089-28788-1-git-send-email-loic.poulain@linaro.org> References: <1623347089-28788-1-git-send-email-loic.poulain@linaro.org> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org From: Johannes Berg In some cases, for example in the upcoming WWAN framework changes, there's no natural "parent netdev", so sometimes dummy netdevs are created or similar. IFLA_PARENT_DEV_NAME is a new attribute intended to contain a device (sysfs, struct device) name that can be used instead when creating a new netdev, if the rtnetlink family implements it. As suggested by Parav Pandit, we also introduce IFLA_PARENT_DEV_BUS_NAME attribute in order to uniquely identify a device on the system (with bus/name pair). ip-link(8) support for the generic parent device attributes will help us avoid code duplication, so no other link type will require a custom code to handle the parent name attribute. E.g. the WWAN interface creation command will looks like this: $ ip link add wwan0-1 parent-dev wwan0 type wwan channel-id 1 So, some future subsystem (or driver) FOO will have an interface creation command that looks like this: $ ip link add foo1-3 parent-dev foo1 type foo bar-id 3 baz-type Y Below is an example of dumping link info of a random device with these new attributes: $ ip --details link show wlp0s20f3 4: wlp0s20f3: mtu 1500 qdisc noqueue state UP mode DORMANT group default qlen 1000 ... parent_devname 0000:00:14.3 parent_busname pci Co-developed-by: Sergey Ryazanov Signed-off-by: Sergey Ryazanov Co-developed-by: Loic Poulain Signed-off-by: Loic Poulain Suggested-by: Sergey Ryazanov Signed-off-by: Johannes Berg --- v2: - Squashed Johannes and Sergey changes - Added IFLA_PARENT_DEV_BUS_NAME attribute - reworded commit message + introduce Sergey's comment include/uapi/linux/if_link.h | 7 +++++++ net/core/rtnetlink.c | 12 ++++++++++++ 2 files changed, 19 insertions(+) diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index a5a7f0e..4882e81 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -341,6 +341,13 @@ enum { IFLA_ALT_IFNAME, /* Alternative ifname */ IFLA_PERM_ADDRESS, IFLA_PROTO_DOWN_REASON, + + /* device (sysfs) name as parent, used instead + * of IFLA_LINK where there's no parent netdev + */ + IFLA_PARENT_DEV_NAME, + IFLA_PARENT_DEV_BUS_NAME, + __IFLA_MAX }; diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 92c3e43..32599f3 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1821,6 +1821,16 @@ static int rtnl_fill_ifinfo(struct sk_buff *skb, if (rtnl_fill_prop_list(skb, dev)) goto nla_put_failure; + if (dev->dev.parent && + nla_put_string(skb, IFLA_PARENT_DEV_NAME, + dev_name(dev->dev.parent))) + goto nla_put_failure; + + if (dev->dev.parent && dev->dev.parent->bus && + nla_put_string(skb, IFLA_PARENT_DEV_BUS_NAME, + dev->dev.parent->bus->name)) + goto nla_put_failure; + nlmsg_end(skb, nlh); return 0; @@ -1880,6 +1890,8 @@ static const struct nla_policy ifla_policy[IFLA_MAX+1] = { [IFLA_PERM_ADDRESS] = { .type = NLA_REJECT }, [IFLA_PROTO_DOWN_REASON] = { .type = NLA_NESTED }, [IFLA_NEW_IFINDEX] = NLA_POLICY_MIN(NLA_S32, 1), + [IFLA_PARENT_DEV_NAME] = { .type = NLA_NUL_STRING }, + [IFLA_PARENT_DEV_BUS_NAME] = { .type = NLA_NUL_STRING }, }; static const struct nla_policy ifla_info_policy[IFLA_INFO_MAX+1] = {