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=-6.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_PASS 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 09275C43381 for ; Mon, 18 Feb 2019 18:21:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id CD5F3217D9 for ; Mon, 18 Feb 2019 18:21:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392063AbfBRSV3 (ORCPT ); Mon, 18 Feb 2019 13:21:29 -0500 Received: from mx2.suse.de ([195.135.220.15]:45906 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2389263AbfBRSV2 (ORCPT ); Mon, 18 Feb 2019 13:21:28 -0500 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 7C885AEA9; Mon, 18 Feb 2019 18:21:26 +0000 (UTC) Received: by unicorn.suse.cz (Postfix, from userid 1000) id 833C5E0122; Mon, 18 Feb 2019 19:21:24 +0100 (CET) Message-Id: From: Michal Kubecek Subject: [RFC PATCH net-next v3 00/21] ethtool netlink interface, part 1 To: netdev@vger.kernel.org Cc: David Miller , Andrew Lunn , Jakub Kicinski , Jiri Pirko , linux-kernel@vger.kernel.org Date: Mon, 18 Feb 2019 19:21:24 +0100 (CET) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Note: this is marked as RFC because it's rather late in the cycle; the plan is to make a regular submission (with changes based on review) once net-next reopens after the 5.1 merge window. The full (work in progress) series, together with the (userspace) ethtool counterpart can be found at https://github.com/mkubecek/ethnl This is first part of alternative userspace interface for ethtool. The aim is to address some long known issues with the ioctl interface, mainly lack of extensibility, raciness, limited error reporting and absence of notifications. The interface uses generic netlink family "ethtool"; it provides multicast group "monitor" which is used for notifications. Documentation for the interface is in Documentation/networking/ethtool-netlink.txt Basic concepts: - the goal is to provide all features of ioctl interface but allow easier future extensions; at some point, it should be possible to have full ethtool functionality without using the ioctl interface - inextensibility of ioctl interface resulted in way too many commands, many of them obsoleted by newer ones; reduce the number by ignoring the obsolete commands and grouping some together - for "set" type commands, allows passing only the attributes to be changed; therefore we don't need a get-modify-set cycle (which is inherently racy), userspace can simply say what it wants to change - provide notifications to multicast group "monitor" like rtnetlink does, i.e. in the form of messages close to replies to "get" requests - allow dump requests to get some information about all network devices providing it - be less dependent on ethtool and kernel being in sync; allow e.g. saying "ethtool -s eth0 advertise foo off" without ethtool knowing what "foo" means; it's kernel's job to know what mode "xyz" is and if it exists and is supported Main changes between RFC v2 and RFC v3: - do not allow building as a module (no netdev notifiers needed) - drop some obsolete fields - add permanent hw address, timestamping and private flags support - rework bitset handling to get rid of variable length arrays - notify monitor on device renames - restructure GET_SETTINGS/SET_SETTINGS messages - split too long patches and submit only first part of the series Main changes between RFC v1 and RFC v2: - support dumps for all "get" requests - provide notifications for changes related to supported request types - support getting string sets (both global and per device) - support getting/setting device features - get rid of family specific header, everything passed as attributes - split netlink code into multiple files in net/ethtool/ directory ToDo / open questions: - some features provided by ethtool would rather belong to devlink (and some are already superseded by devlink); however, only few drivers provide devlink interface at the moment and as recent discussion on flashing revealed, we cannot rely on devlink's presence - while the netlink interface allows easy future extensions, ethtool_ops interface does not; some settings could be implemented using tunables and accessed via relevant netlink messages (as well as tunables) from userspace but in the long term, something better will be needed - currently, all communication with drivers via ethtool_ops is done under RTNL as this is what ioctl interface does and likely many ethtool_ops handlers rely on that; if we are going to rework ethtool_ops in the future ("phase two"), it would be nice to get rid of it - ethtool_ops should pass extack pointer to allow drivers more meaningful error reporting; it's not clear, however, how to pass information about offending attribute - notifications are sent whenever a change is done via netlink API or ioctl API and for netdev features also whenever they are updated using netdev_change_features(); it would be desirable to notify also about link state and negotiation result (speed/duplex and partner link modes) but it would be more tricky Michal Kubecek (21): netlink: introduce nla_put_bitfield32() ethtool: move to its own directory ethtool: introduce ethtool netlink interface ethtool: helper functions for netlink interface ethtool: netlink bitset handling ethtool: support for netlink notifications ethtool: implement EVENT notifications ethtool: generic handlers for GET requests ethtool: move string arrays into common file ethtool: provide string sets with GET_STRSET request ethtool: provide driver/device information in GET_INFO request ethtool: provide permanent hardware address in GET_INFO request ethtool: provide timestamping information in GET_INFO request ethtool: provide link mode names as a string set ethtool: provide link settings and link modes in GET_SETTINGS request ethtool: provide WoL information in GET_SETTINGS request ethtool: provide message level in GET_SETTINGS request ethtool: provide link state in GET_SETTINGS request ethtool: provide device features in GET_SETTINGS request ethtool: provide private flags in GET_SETTINGS request ethtool: send netlink notifications about setting changes Documentation/networking/ethtool-netlink.txt | 441 +++++++++++++ include/linux/ethtool_netlink.h | 17 + include/linux/netdevice.h | 14 + include/net/netlink.h | 15 + include/uapi/linux/ethtool.h | 10 + include/uapi/linux/ethtool_netlink.h | 265 ++++++++ include/uapi/linux/net_tstamp.h | 13 + net/Kconfig | 8 + net/Makefile | 2 +- net/core/Makefile | 2 +- net/ethtool/Makefile | 7 + net/ethtool/bitset.c | 572 +++++++++++++++++ net/ethtool/bitset.h | 40 ++ net/ethtool/common.c | 227 +++++++ net/ethtool/common.h | 29 + net/ethtool/info.c | 332 ++++++++++ net/{core/ethtool.c => ethtool/ioctl.c} | 244 ++----- net/ethtool/netlink.c | 634 +++++++++++++++++++ net/ethtool/netlink.h | 252 ++++++++ net/ethtool/settings.c | 559 ++++++++++++++++ net/ethtool/strset.c | 461 ++++++++++++++ 21 files changed, 3937 insertions(+), 207 deletions(-) create mode 100644 Documentation/networking/ethtool-netlink.txt create mode 100644 include/linux/ethtool_netlink.h create mode 100644 include/uapi/linux/ethtool_netlink.h create mode 100644 net/ethtool/Makefile create mode 100644 net/ethtool/bitset.c create mode 100644 net/ethtool/bitset.h create mode 100644 net/ethtool/common.c create mode 100644 net/ethtool/common.h create mode 100644 net/ethtool/info.c rename net/{core/ethtool.c => ethtool/ioctl.c} (91%) create mode 100644 net/ethtool/netlink.c create mode 100644 net/ethtool/netlink.h create mode 100644 net/ethtool/settings.c create mode 100644 net/ethtool/strset.c -- 2.20.1