From patchwork Mon May 27 11:16:11 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Timo Teras X-Patchwork-Id: 246578 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id DE6492C030C for ; Mon, 27 May 2013 21:15:02 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757856Ab3E0LOp (ORCPT ); Mon, 27 May 2013 07:14:45 -0400 Received: from mail-ea0-f178.google.com ([209.85.215.178]:47015 "EHLO mail-ea0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757704Ab3E0LOm (ORCPT ); Mon, 27 May 2013 07:14:42 -0400 Received: by mail-ea0-f178.google.com with SMTP id q16so3821979ead.37 for ; Mon, 27 May 2013 04:14:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references:mime-version:content-type:content-transfer-encoding; bh=F4Y4XDO3t6xezYhj9SDkUAKoQ0qc4yjHWbeyhMz7eUU=; b=zARMNSSIJUUqDjez4DK4DorehZz+GQh/Mtl/FiQizdCUAXIf0LJEgBkAER0z27Man1 vhiyMG8S9v/d4XZ8OvPUkvX9yH44bsv+CWb80L0jGOsH77qo5BE09haZRPypOfRHeNUt wFzjS0Ap8ShuTbnrWjQK3KwIc9ULhHbBOh904KC9qRHHt2TXzcZYzhlt36nEFAhMAYkw za/SAKU6O/vWsSPgNHCjc6Ulq5sEnbe+FUSsPyYQYlymsH+GgaTjOnaDont/TpKxyp2k zQhZnP/9OWjzsx8nwyquI0UUXMHDl3b8Bm8il6Z+pBoi2y4ctjjyln8Fy8cGSVziAHUV pjLw== X-Received: by 10.15.35.71 with SMTP id f47mr53829701eev.15.1369653281485; Mon, 27 May 2013 04:14:41 -0700 (PDT) Received: from vostro.util.wtbts.net ([83.145.235.199]) by mx.google.com with ESMTPSA id e1sm6514935eem.10.2013.05.27.04.14.40 for (version=TLSv1.2 cipher=ECDHE-RSA-RC4-SHA bits=128/128); Mon, 27 May 2013 04:14:40 -0700 (PDT) From: =?UTF-8?q?Timo=20Ter=C3=A4s?= To: netdev@vger.kernel.org Cc: =?UTF-8?q?Timo=20Ter=C3=A4s?= Subject: [PATCH net-next 1/6] net: inform NETDEV_CHANGE callbacks which flags were changed Date: Mon, 27 May 2013 14:16:11 +0300 Message-Id: <1369653376-4731-2-git-send-email-timo.teras@iki.fi> X-Mailer: git-send-email 1.8.2.3 In-Reply-To: <1369653376-4731-1-git-send-email-timo.teras@iki.fi> References: <1369653376-4731-1-git-send-email-timo.teras@iki.fi> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org In certain cases (like the follow up commit to arp.c) will need to check which flags actually changed to avoid excessive work. Ben Hutchings nicely worded why to put these transient flags to struct net_device for the time being: > It's inelegant to put transient data associated with an event in a > persistent data structure. On the other hand, having every user cache > the old state is pretty awful as well. > > Really, netdev notifiers should be changed to accept a structure that > encapsulates the changes rather than just a pointer to the net_device. > But making such a change would be an enormous pain and error-prone > because notifier functions aren't type-safe. > > As an interim solution, I think either the general flags_changed or > old_flags would be preferable to defining extra transient flags. Signed-off-by: Timo Teräs Acked-by: Ben Hutchings --- include/linux/netdevice.h | 4 +++- net/core/dev.c | 5 ++++- 2 files changed, 7 insertions(+), 2 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index ea7b6bc..f336e03 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1112,7 +1112,9 @@ struct net_device { /* Hardware header description */ const struct header_ops *header_ops; - unsigned int flags; /* interface flags (a la BSD) */ + unsigned int flags; /* interface flags (a la BSD) */ + unsigned int flags_changed; /* flags that are being changed + * valid during NETDEV_CHANGE notifier */ unsigned int priv_flags; /* Like 'flags' but invisible to userspace. * See if.h for definitions. */ unsigned short gflags; diff --git a/net/core/dev.c b/net/core/dev.c index 50c02de..bbaa3c2 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4742,8 +4742,11 @@ void __dev_notify_flags(struct net_device *dev, unsigned int old_flags) } if (dev->flags & IFF_UP && - (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) + (changes & ~(IFF_UP | IFF_PROMISC | IFF_ALLMULTI | IFF_VOLATILE))) { + dev->flags_changed = changes; call_netdevice_notifiers(NETDEV_CHANGE, dev); + dev->flags_changed = 0; + } } /**