From mboxrd@z Thu Jan 1 00:00:00 1970 From: Konstantin Khlebnikov Subject: [PATCH 3/3] ipvlan: set dev_id for l2 ports to generate unique IPv6 addresses Date: Thu, 14 May 2015 16:56:20 +0300 Message-ID: <20150514135620.14062.1034.stgit@buzz> References: <20150514134657.14062.87579.stgit@buzz> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Cc: Mahesh Bandewar , Jiri Benc , Hannes Frederic Sowa To: netdev@vger.kernel.org, "David S. Miller" Return-path: Received: from forward-corp1g.mail.yandex.net ([95.108.253.251]:44678 "EHLO forward-corp1g.mail.yandex.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933315AbbENN4Y (ORCPT ); Thu, 14 May 2015 09:56:24 -0400 In-Reply-To: <20150514134657.14062.87579.stgit@buzz> Sender: netdev-owner@vger.kernel.org List-ID: All ipvlan ports use one MAC address, this way ipv6 RA tries to assign one ipv6 address to all of them. This patch assigns unique dev_id to each ipvlan port. This field is used instead of common FF-FE in Modified EUI-64. Signed-off-by: Konstantin Khlebnikov --- Documentation/networking/ipvlan.txt | 12 +++++++++++- drivers/net/ipvlan/ipvlan.h | 1 + drivers/net/ipvlan/ipvlan_main.c | 20 ++++++++++++++++++++ 3 files changed, 32 insertions(+), 1 deletion(-) diff --git a/Documentation/networking/ipvlan.txt b/Documentation/networking/ipvlan.txt index cf996394e466..cb0b777bce58 100644 --- a/Documentation/networking/ipvlan.txt +++ b/Documentation/networking/ipvlan.txt @@ -24,7 +24,7 @@ using IProute2/ip utility. ip link add link type ipvlan mode { l2 | L3 } - e.g. ip link add link ipvl0 eth0 type ipvlan mode l2 + e.g. ip link add link eth0 ipvl0 type ipvlan mode l2 4. Operating modes: @@ -41,6 +41,15 @@ slave device and packets are switched and queued to the master device to send out. In this mode the slaves will RX/TX multicast and broadcast (if applicable) as well. + In L2 mode slave devices receive Router Advertisements from the network +and perform autoconfiguration as well as master device. Each port has unique +16-bit device id which is used for filling octets 4-5 of Modified EUI-64. +That gives 65533 addresses (FF-FE used by master, FF-FF/00-00 reserved/not used). + + Also lower half of IPv6 address could be set as interface token: + + ip token set ::aaaa:bbbb:cccc:dddd dev ipvl0 + 4.2 L3 mode: In this mode TX processing upto L3 happens on the stack instance attached to the slave device and packets are switched to the stack instance of the @@ -105,3 +114,4 @@ namespace where L2 on the slave could be changed / misused. (4) ip -4 addr add 127.0.0.1 dev lo (5) ip -4 addr add $IPADDR dev ipvl1 (6) ip -4 route add default via $ROUTER dev ipvl1 + diff --git a/drivers/net/ipvlan/ipvlan.h b/drivers/net/ipvlan/ipvlan.h index 54549a6223dd..1ebab84e7a0e 100644 --- a/drivers/net/ipvlan/ipvlan.h +++ b/drivers/net/ipvlan/ipvlan.h @@ -95,6 +95,7 @@ struct ipvl_port { struct rcu_head rcu; int count; u16 mode; + struct ida ida; }; static inline struct ipvl_port *ipvlan_port_get_rcu(const struct net_device *d) diff --git a/drivers/net/ipvlan/ipvlan_main.c b/drivers/net/ipvlan/ipvlan_main.c index 0cafd3e6f02d..dee0e8441150 100644 --- a/drivers/net/ipvlan/ipvlan_main.c +++ b/drivers/net/ipvlan/ipvlan_main.c @@ -53,6 +53,7 @@ static int ipvlan_port_create(struct net_device *dev) INIT_LIST_HEAD(&port->ipvlans); for (idx = 0; idx < IPVLAN_HASH_SIZE; idx++) INIT_HLIST_HEAD(&port->hlhead[idx]); + ida_init(&port->ida); err = netdev_rx_handler_register(dev, ipvlan_handle_frame, port); if (err) @@ -72,6 +73,7 @@ static void ipvlan_port_destroy(struct net_device *dev) dev->priv_flags &= ~IFF_IPVLAN_MASTER; netdev_rx_handler_unregister(dev); + ida_destroy(&port->ida); kfree_rcu(port, rcu); } @@ -484,6 +486,18 @@ static int ipvlan_link_new(struct net *src_net, struct net_device *dev, */ memcpy(dev->dev_addr, phy_dev->dev_addr, ETH_ALEN); + if (port->mode == IPVLAN_MODE_L2) { + /* + * IPv6 addrconf uses it to produce unique addresses, + * see function addrconf_ifid_eui48. + */ + err = ida_simple_get(&port->ida, 1, 0xFFFE, GFP_KERNEL); + if (err > 0) + dev->dev_id = err; + else if (err != -ENOSPC) + goto ipvlan_destroy_port; + } + dev->priv_flags |= IFF_IPVLAN_SLAVE; port->count += 1; @@ -518,6 +532,12 @@ static void ipvlan_link_delete(struct net_device *dev, struct list_head *head) list_del(&addr->anode); } } + + if (dev->dev_id) { + ida_simple_remove(&ipvlan->port->ida, dev->dev_id); + dev->dev_id = 0; + } + list_del_rcu(&ipvlan->pnode); unregister_netdevice_queue(dev, head); netdev_upper_dev_unlink(ipvlan->phy_dev, dev);