From patchwork Thu Mar 13 03:15:27 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Luis R. Rodriguez" X-Patchwork-Id: 329780 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 540692C00C2 for ; Thu, 13 Mar 2014 14:16:19 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753319AbaCMDPx (ORCPT ); Wed, 12 Mar 2014 23:15:53 -0400 Received: from mail-pa0-f41.google.com ([209.85.220.41]:63891 "EHLO mail-pa0-f41.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752715AbaCMDPv (ORCPT ); Wed, 12 Mar 2014 23:15:51 -0400 Received: by mail-pa0-f41.google.com with SMTP id fa1so458820pad.28 for ; Wed, 12 Mar 2014 20:15:51 -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:in-reply-to:references; bh=CmvzG7sQRcMEhyGShHQ+/jWsnFIk9Dm8UQ0YiTKJiD0=; b=dHol0CqJMAvWVWYhXSdcgcZyKHQN2XnLDt7oyHOCeLwvODk3Ol8YlQ/EuRQFVgPLLS c5yuB90X3gGNJLrZPgIKBQaMgBzhCtXeqyrPVTvk7W3/hNSBOVW7LU+JB7d37J3jF8qF O1o6gWr/5dsGxsv9U2JuvbGw21PJOH7fTacALuYlVd0qAzuRbg9PcGx3mvVKKBLYsXd4 SLIXzep3BewKQ8xZDpc+D4h2B4xbdjHFZ0GtzOH7cuXVvbj7tUDSBBpApkJXMIzdLO78 TZxXtLG91sxxBM8+M/R8LJ9ca36mp3JFcCFT7G8LTUnVMICSkTePzNhvpOaphyAA92Cb QtOA== X-Received: by 10.68.252.165 with SMTP id zt5mr1310025pbc.17.1394680551057; Wed, 12 Mar 2014 20:15:51 -0700 (PDT) Received: from mcgrof@gmail.com (c-98-234-145-61.hsd1.ca.comcast.net. [98.234.145.61]) by mx.google.com with ESMTPSA id oz7sm1889316pbc.41.2014.03.12.20.15.47 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Wed, 12 Mar 2014 20:15:49 -0700 (PDT) Received: by mcgrof@gmail.com (sSMTP sendmail emulation); Wed, 12 Mar 2014 20:15:46 -0700 From: "Luis R. Rodriguez" To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, kvm@vger.kernel.org, xen-devel@lists.xenproject.org, mcgrof@suse.com, Stephen Hemminger , bridge@lists.linux-foundation.org Subject: [PATCH 3/3] bridge: fix bridge root block on designated port Date: Wed, 12 Mar 2014 20:15:27 -0700 Message-Id: <1394680527-28970-4-git-send-email-mcgrof@do-not-panic.com> X-Mailer: git-send-email 1.8.5.3 In-Reply-To: <1394680527-28970-1-git-send-email-mcgrof@do-not-panic.com> References: <1394680527-28970-1-git-send-email-mcgrof@do-not-panic.com> Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: "Luis R. Rodriguez" Root port blocking was designed so that a bridge port can opt out of becoming the designated root port for a bridge. If a port however first becomes the designated root port and we then toggle the root port block on it we currently don't kick that port out of the designated root port. This fixes that. This is particularly important for net_devices that would wish to never become a root port from the start, currently toggling that off will enable root port flag but it won't really kick the bridge and do what you'd expect, the MAC address is kept on the bridge of the toggled port for root_block if it was the designated port. In order to catch if a port with root port block preference is set we need to move our check for root block prior to the root selection so check for root blocked ports upon eveyr br_configuration_update(). We also simply just prevent the root-blocked ports from consideration as root port candidates on br_should_become_root_port() and br_stp_recalculate_bridge_id(). The issue that this patch is trying to address and fix can be tested easily before and after this patch is applied using 2 TAP net_devices and then toggling at will with the root_block knob. ip tuntap add dev tap0 mode tap ip tuntap add dev tap1 mode tap ip link add dev br0 type bridge ip link show br0 echo ------------------------------------------- ip link set dev tap0 master br0 ip link echo ------------------------------------------- ip link set dev tap1 master br0 ip link echo ------------------------------------------- Upon review at the above results you can toggle root_block on each port to see if you see the results you expect. bridge link set dev tap0 root_block on ip link bridge link set dev tap1 root_block on ip link Toggling off root_block on any port should will bring back the port to be a candidate for designated root port: bridge link set dev tap1 root_block off ip link bridge link set dev tap0 root_block off ip link To nuke: ip tuntap del tap0 mode tap ip tuntap del tap0 mode tap Cc: Stephen Hemminger Cc: bridge@lists.linux-foundation.org Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org Cc: kvm@vger.kernel.org Signed-off-by: Luis R. Rodriguez --- net/bridge/br_netlink.c | 18 ++++++++++++ net/bridge/br_private.h | 1 + net/bridge/br_stp.c | 73 +++++++++++++++++++++++++++++++++++++++++++++---- net/bridge/br_stp_if.c | 3 +- 4 files changed, 88 insertions(+), 7 deletions(-) diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c index 6f1b26d..fbec354 100644 --- a/net/bridge/br_netlink.c +++ b/net/bridge/br_netlink.c @@ -324,6 +324,21 @@ static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[], } } +static void br_kick_bridge_port(struct net_bridge_port *p) +{ + struct net_bridge *br = p->br; + bool wasroot; + + wasroot = br_is_root_bridge(br); + br_become_designated_port(p); + + br_configuration_update(br); + br_port_state_selection(br); + + if (br_is_root_bridge(br) && !wasroot) + br_become_root_bridge(br); +} + /* Process bridge protocol info on port */ static int br_setport(struct net_bridge_port *p, struct nlattr *tb[]) { @@ -353,6 +368,9 @@ static int br_setport(struct net_bridge_port *p, struct nlattr *tb[]) if (err) return err; } + + br_kick_bridge_port(p); + return 0; } diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index 32a06da..45d7917 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -150,6 +150,7 @@ struct net_bridge_port u8 priority; u8 state; u16 port_no; + bool root_block_enabled; unsigned char topology_change_ack; unsigned char config_pending; port_id port_id; diff --git a/net/bridge/br_stp.c b/net/bridge/br_stp.c index 3c86f05..f5741f3 100644 --- a/net/bridge/br_stp.c +++ b/net/bridge/br_stp.c @@ -59,6 +59,7 @@ static int br_should_become_root_port(const struct net_bridge_port *p, br = p->br; if (p->state == BR_STATE_DISABLED || + (p->flags & BR_ROOT_BLOCK) || br_is_designated_port(p)) return 0; @@ -104,7 +105,7 @@ static void br_root_port_block(const struct net_bridge *br, struct net_bridge_port *p) { - br_notice(br, "port %u(%s) tried to become root port (blocked)", + br_notice(br, "port %u (%s) is now root blocked", (unsigned int) p->port_no, p->dev->name); p->state = BR_STATE_LISTENING; @@ -124,11 +125,7 @@ static void br_root_selection(struct net_bridge *br) list_for_each_entry(p, &br->port_list, list) { if (!br_should_become_root_port(p, root_port)) continue; - - if (p->flags & BR_ROOT_BLOCK) - br_root_port_block(br, p); - else - root_port = p->port_no; + root_port = p->port_no; } br->root_port = root_port; @@ -358,10 +355,74 @@ static void br_reply(struct net_bridge_port *p) br_transmit_config(p); } +static bool br_root_port_block_check(struct net_bridge_port *p) +{ + bool designated = false; + + if (p->root_block_enabled && + !(p->flags & BR_ROOT_BLOCK)) { + br_notice(p->br, "port %u (%s) is root block toggled off", + (unsigned int) p->port_no, p->dev->name); + return false; + } + + if (p->flags & BR_ROOT_BLOCK && + (p->root_block_enabled)) + return false; + + if (!(p->flags & BR_ROOT_BLOCK)) + return false; + + if (br_is_designated_port(p)) { + designated = true; + p->flags = BR_ROOT_BLOCK | + BR_LEARNING | + BR_FLOOD; + p->priority = 0x8000 >> BR_PORT_BITS; + br_init_port(p); + } + + br_root_port_block(p->br, p); + p->root_block_enabled = true; + + return designated; +} + +/* Updates block ports as required and returns true if one was designated */ +static bool br_update_block_ports(struct net_bridge *br) +{ + struct net_bridge_port *p; + bool designated = false; + + list_for_each_entry(p, &br->port_list, list) { + designated = br_root_port_block_check(p); + if (designated) + return designated; + } + + return false; +} + +static void br_update_designated_port(struct net_bridge *br) +{ + struct net_bridge_port *p; + + list_for_each_entry(p, &br->port_list, list) + br_become_designated_port(p); +} + /* called under bridge lock */ void br_configuration_update(struct net_bridge *br) { + bool designated_was_blocked = false; + + designated_was_blocked = br_update_block_ports(br); + br_root_selection(br); + + if (designated_was_blocked) + br_update_designated_port(br); + br_designated_port_selection(br); } diff --git a/net/bridge/br_stp_if.c b/net/bridge/br_stp_if.c index 4c9ad45..62b84af 100644 --- a/net/bridge/br_stp_if.c +++ b/net/bridge/br_stp_if.c @@ -230,10 +230,11 @@ bool br_stp_recalculate_bridge_id(struct net_bridge *br) return false; list_for_each_entry(p, &br->port_list, list) { + if (p->flags & BR_ROOT_BLOCK) + continue; if (addr == br_mac_zero || memcmp(p->dev->dev_addr, addr, ETH_ALEN) < 0) addr = p->dev->dev_addr; - } if (ether_addr_equal(br->bridge_id.addr, addr))