From patchwork Tue Aug 14 15:05:34 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Pirko X-Patchwork-Id: 1321061 Return-Path: X-Original-To: patchwork-linux-rdma@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id D75F8DF215 for ; Tue, 14 Aug 2012 15:12:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756487Ab2HNPGA (ORCPT ); Tue, 14 Aug 2012 11:06:00 -0400 Received: from mail-ey0-f174.google.com ([209.85.215.174]:56018 "EHLO mail-ey0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756390Ab2HNPF5 (ORCPT ); Tue, 14 Aug 2012 11:05:57 -0400 Received: by mail-ey0-f174.google.com with SMTP id c11so194842eaa.19 for ; Tue, 14 Aug 2012 08:05:57 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references :x-gm-message-state; bh=dFya40O513n8D3FkXQlNdNScThsXQ3pkr3git70ytBo=; b=IQO9H5z2z2bOp1cqPotBwdqP7GBtnei8dyL9hyLFlSVbFHyjg2Z/idB1yZ+rnlCLm4 BHNFp3iagFB6r8PvYC7IUyMcrLHWsXoSw6hwhI+2dYyZwzIauCw1TycOk0yX9SySPP7K vTr3WUO7RV9HxC3Nwtc2rqGdPWmGkJ73AaC+jwsg/x1dj2EHiMdTdYa0iHFqvfVLvYbs RJCR/pOmtfW9WdUI6XQr/C1+OpgXhdMJl+RhDFGoiqkXlplN8Vlbgmcsj0K5WHFDrvvx gtNFWAbDr0YsRknzk3lA5Y53eLzzw9wHg2MzEIlttr5T2Xe1T/qEr7YSaW7/onLQMxAB VAuA== Received: by 10.14.181.132 with SMTP id l4mr15743612eem.17.1344956756612; Tue, 14 Aug 2012 08:05:56 -0700 (PDT) Received: from localhost (nat-pool-brq-t.redhat.com. [209.132.186.34]) by mx.google.com with ESMTPS id l42sm7624198eep.1.2012.08.14.08.05.55 (version=TLSv1/SSLv3 cipher=OTHER); Tue, 14 Aug 2012 08:05:55 -0700 (PDT) From: Jiri Pirko To: netdev@vger.kernel.org Cc: davem@davemloft.net, edumazet@google.com, faisal.latif@intel.com, roland@kernel.org, sean.hefty@intel.com, hal.rosenstock@gmail.com, fubar@us.ibm.com, andy@greyhouse.net, divy@chelsio.com, jitendra.kalsaria@qlogic.com, sony.chacko@qlogic.com, linux-driver@qlogic.com, kaber@trash.net, ursula.braun@de.ibm.com, blaschka@linux.vnet.ibm.com, linux390@de.ibm.com, shemminger@vyatta.com, bhutchings@solarflare.com, therbert@google.com, xiyou.wangcong@gmail.com, joe@perches.com, gregory.v.rose@intel.com, john.r.fastabend@intel.com, linux-rdma@vger.kernel.org, linux-kernel@vger.kernel.org, linux-s390@vger.kernel.org, bridge@lists.linux-foundation.org, fbl@redhat.com Subject: [patch net-next v2 01/15] net: introduce upper device lists Date: Tue, 14 Aug 2012 17:05:34 +0200 Message-Id: <1344956748-2099-2-git-send-email-jiri@resnulli.us> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1344956748-2099-1-git-send-email-jiri@resnulli.us> References: <1344956748-2099-1-git-send-email-jiri@resnulli.us> X-Gm-Message-State: ALoCoQn2+x5G4ghMaT+Cxl7aYOL6t+L6TAd/Xn/MMpnYGMAGmMILuXzT2qC965ru9mTMRhpXnXN8 Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org This lists are supposed to serve for storing pointers to all upper devices. Eventually it will replace dev->master pointer which is used for bonding, bridge, team but it cannot be used for vlan, macvlan where there might be multiple upper present. In case the upper link is replacement for dev->master, it is marked with "master" flag. New upper device list resolves this limitation. Also, the information stored in lists is used for preventing looping setups like "bond->somethingelse->samebond" Signed-off-by: Jiri Pirko --- include/linux/netdevice.h | 14 +++ net/core/dev.c | 236 ++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 246 insertions(+), 4 deletions(-) diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h index a9db4f3..95345d4 100644 --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1173,6 +1173,8 @@ struct net_device { * which this device is member of. */ + struct list_head upper_dev_list; /* List of upper devices */ + /* Interface address info used in eth_type_trans() */ unsigned char *dev_addr; /* hw address, (before bcast because most packets are @@ -2611,6 +2613,18 @@ extern int netdev_max_backlog; extern int netdev_tstamp_prequeue; extern int weight_p; extern int bpf_jit_enable; + +extern bool netdev_has_upper_dev(struct net_device *dev, + struct net_device *upper_dev); +extern bool netdev_has_any_upper_dev(struct net_device *dev); +extern struct net_device *netdev_master_upper_dev_get(struct net_device *dev); +extern struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev); +extern int netdev_upper_dev_link(struct net_device *dev, + struct net_device *upper_dev); +extern int netdev_master_upper_dev_link(struct net_device *dev, + struct net_device *upper_dev); +extern void netdev_upper_dev_unlink(struct net_device *dev, + struct net_device *upper_dev); extern int netdev_set_master(struct net_device *dev, struct net_device *master); extern int netdev_set_bond_master(struct net_device *dev, struct net_device *master); diff --git a/net/core/dev.c b/net/core/dev.c index 1f06df8..d7fd235 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -4425,6 +4425,229 @@ static int __init dev_proc_init(void) #endif /* CONFIG_PROC_FS */ +struct netdev_upper { + struct net_device *dev; + bool master; + struct list_head list; + struct rcu_head rcu; +}; + +static bool __netdev_has_upper_dev(struct net_device *dev, + struct net_device *upper_dev, + bool deep) +{ + struct netdev_upper *upper; + + list_for_each_entry(upper, &dev->upper_dev_list, list) { + if (upper->dev == upper_dev) + return true; + if (deep && __netdev_has_upper_dev(upper->dev, upper_dev, deep)) + return true; + } + return false; +} + +static struct netdev_upper *__netdev_find_upper(struct net_device *dev, + struct net_device *upper_dev) +{ + struct netdev_upper *upper; + + list_for_each_entry(upper, &dev->upper_dev_list, list) { + if (upper->dev == upper_dev) + return upper; + } + return NULL; +} + +/** + * netdev_has_upper_dev - Check if device is linked to an upper device + * @dev: device + * @upper_dev: upper device to check + * + * Find out if a device is linked to specified upper device and return true + * in case it is. The caller must hold the RTNL semaphore. + */ +bool netdev_has_upper_dev(struct net_device *dev, + struct net_device *upper_dev) +{ + ASSERT_RTNL(); + + return __netdev_has_upper_dev(dev, upper_dev, false); +} +EXPORT_SYMBOL(netdev_has_upper_dev); + +/** + * netdev_has_any_upper_dev - Check if device is linked to some device + * @dev: device + * + * Find out if a device is linked to an upper device and return true in case + * it is. The caller must hold the RTNL semaphore. + */ +bool netdev_has_any_upper_dev(struct net_device *dev) +{ + ASSERT_RTNL(); + + return !list_empty(&dev->upper_dev_list); +} +EXPORT_SYMBOL(netdev_has_any_upper_dev); + +/** + * netdev_master_upper_dev_get - Get master upper device + * @dev: device + * + * Find a master upper device and return pointer to it or NULL in case + * it's not there. The caller must hold the RTNL semaphore. + */ +struct net_device *netdev_master_upper_dev_get(struct net_device *dev) +{ + struct netdev_upper *upper; + + ASSERT_RTNL(); + + if (list_empty(&dev->upper_dev_list)) + return NULL; + + upper = list_first_entry(&dev->upper_dev_list, + struct netdev_upper, list); + if (likely(upper->master)) + return upper->dev; + return NULL; +} +EXPORT_SYMBOL(netdev_master_upper_dev_get); + +/** + * netdev_master_upper_dev_get_rcu - Get master upper device + * @dev: device + * + * Find a master upper device and return pointer to it or NULL in case + * it's not there. The caller must hold the RCU read lock. + */ +struct net_device *netdev_master_upper_dev_get_rcu(struct net_device *dev) +{ + struct netdev_upper *upper; + + upper = list_first_or_null_rcu(&dev->upper_dev_list, + struct netdev_upper, list); + if (upper && likely(upper->master)) + return upper->dev; + return NULL; +} +EXPORT_SYMBOL(netdev_master_upper_dev_get_rcu); + +static int __netdev_upper_dev_link(struct net_device *dev, + struct net_device *upper_dev, bool master) +{ + struct netdev_upper *upper; + + ASSERT_RTNL(); + + if (dev == upper_dev) + return -EBUSY; + /* + * To prevent loops, check if dev is not upper device to upper_dev. + */ + if (__netdev_has_upper_dev(upper_dev, dev, true)) + return -EBUSY; + + if (__netdev_find_upper(dev, upper_dev)) + return -EEXIST; + + if (master && netdev_master_upper_dev_get(dev)) + return -EBUSY; + + upper = kmalloc(sizeof(*upper), GFP_KERNEL); + if (!upper) + return -ENOMEM; + + upper->dev = upper_dev; + upper->master = master; + + /* + * Ensure that master upper link is always the first item in the list. + */ + if (master) + list_add_rcu(&upper->list, &dev->upper_dev_list); + else + list_add_tail_rcu(&upper->list, &dev->upper_dev_list); + dev_hold(upper_dev); + + return 0; +} +/** + * netdev_upper_dev_link - Add a link to the upper device + * @dev: device + * @upper_dev: new upper device + * + * Adds a link to device which is upper to this one. The caller must hold + * the RTNL semaphore. On a failure a negative errno code is returned. + * On success the reference counts are adjusted and the function + * returns zero. + */ +int netdev_upper_dev_link(struct net_device *dev, + struct net_device *upper_dev) +{ + return __netdev_upper_dev_link(dev, upper_dev, false); +} +EXPORT_SYMBOL(netdev_upper_dev_link); + +/** + * netdev_master_upper_dev_link - Add a master link to the upper device + * @dev: device + * @upper_dev: new upper device + * + * Adds a link to device which is upper to this one. In this case, only + * one master upper device can be linked, although other non-master devices + * might be linked as well. The caller must hold the RTNL semaphore. + * On a failure a negative errno code is returned. On success the reference + * counts are adjusted and the function returns zero. + */ +int netdev_master_upper_dev_link(struct net_device *dev, + struct net_device *upper_dev) +{ + return __netdev_upper_dev_link(dev, upper_dev, true); +} +EXPORT_SYMBOL(netdev_master_upper_dev_link); + +/** + * netdev_upper_free_rcu - Frees a upper device list item via the RCU pointer + * @entry: the entry's RCU field + * + * This function is designed to be used as a callback to the call_rcu() + * function so that the memory allocated to the netdev upper device list item + * can be released safely. + */ +static void netdev_upper_free_rcu(struct rcu_head *entry) +{ + struct netdev_upper *upper; + + upper = container_of(entry, struct netdev_upper, rcu); + kfree(upper); +} + +/** + * netdev_upper_dev_unlink - Removes a link to upper device + * @dev: device + * @upper_dev: new upper device + * + * Removes a link to device which is upper to this one. The caller must hold + * the RTNL semaphore. + */ +void netdev_upper_dev_unlink(struct net_device *dev, + struct net_device *upper_dev) +{ + struct netdev_upper *upper; + + ASSERT_RTNL(); + + upper = __netdev_find_upper(dev, upper_dev); + if (!upper) + return; + list_del_rcu(&upper->list); + dev_put(upper_dev); + call_rcu(&upper->rcu, netdev_upper_free_rcu); +} +EXPORT_SYMBOL(netdev_upper_dev_unlink); + /** * netdev_set_master - set up master pointer * @slave: slave device @@ -4438,19 +4661,23 @@ static int __init dev_proc_init(void) int netdev_set_master(struct net_device *slave, struct net_device *master) { struct net_device *old = slave->master; + int err; ASSERT_RTNL(); if (master) { if (old) return -EBUSY; - dev_hold(master); + err = netdev_master_upper_dev_link(slave, master); + if (err) + return err; } slave->master = master; if (old) - dev_put(old); + netdev_upper_dev_unlink(slave, master); + return 0; } EXPORT_SYMBOL(netdev_set_master); @@ -5297,8 +5524,8 @@ static void rollback_registered_many(struct list_head *head) if (dev->netdev_ops->ndo_uninit) dev->netdev_ops->ndo_uninit(dev); - /* Notifier chain MUST detach us from master device. */ - WARN_ON(dev->master); + /* Notifier chain MUST detach us all upper devices. */ + WARN_ON(netdev_has_any_upper_dev(dev)); /* Remove entries from kobject tree */ netdev_unregister_kobject(dev); @@ -5999,6 +6226,7 @@ struct net_device *alloc_netdev_mqs(int sizeof_priv, const char *name, INIT_LIST_HEAD(&dev->napi_list); INIT_LIST_HEAD(&dev->unreg_list); INIT_LIST_HEAD(&dev->link_watch_list); + INIT_LIST_HEAD(&dev->upper_dev_list); dev->priv_flags = IFF_XMIT_DST_RELEASE; setup(dev);