net/openvswitch/vport-netdev.c

   1 /*
   2  * Copyright (c) 2007-2012 Nicira, Inc.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of version 2 of the GNU General Public
   6  * License as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301, USA
  17  */
  18
  19 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  20
  21 #include <linux/if_arp.h>
  22 #include <linux/if_bridge.h>
  23 #include <linux/if_vlan.h>
  24 #include <linux/kernel.h>
  25 #include <linux/llc.h>
  26 #include <linux/rtnetlink.h>
  27 #include <linux/skbuff.h>
  28 #include <linux/openvswitch.h>
  29 #include <linux/export.h>
  30
  31 #include <net/ip_tunnels.h>
  32 #include <net/rtnetlink.h>
  33
  34 #include "datapath.h"
  35 #include "vport.h"
  36 #include "vport-internal_dev.h"
  37 #include "vport-netdev.h"
  38
  39 static struct vport_ops ovs_netdev_vport_ops;
  40
  41 /* Must be called with rcu_read_lock. */
  42 static void netdev_port_receive(struct sk_buff *skb)
  43 {
  44         struct vport *vport;
  45
  46         vport = ovs_netdev_get_vport(skb->dev);
  47         if (unlikely(!vport))
  48                 goto error;
  49
  50         if (unlikely(skb_warn_if_lro(skb)))
  51                 goto error;
  52
  53         /* Make our own copy of the packet.  Otherwise we will mangle the
  54          * packet for anyone who came before us (e.g. tcpdump via AF_PACKET).
  55          */
  56         skb = skb_share_check(skb, GFP_ATOMIC);
  57         if (unlikely(!skb))
  58                 return;
  59
  60         skb_push(skb, ETH_HLEN);
  61         ovs_skb_postpush_rcsum(skb, skb->data, ETH_HLEN);
  62         ovs_vport_receive(vport, skb, skb_tunnel_info(skb));
  63         return;
  64 error:
  65         kfree_skb(skb);
  66 }
  67
  68 /* Called with rcu_read_lock and bottom-halves disabled. */
  69 static rx_handler_result_t netdev_frame_hook(struct sk_buff **pskb)
  70 {
  71         struct sk_buff *skb = *pskb;
  72
  73         if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
  74                 return RX_HANDLER_PASS;
  75
  76         netdev_port_receive(skb);
  77         return RX_HANDLER_CONSUMED;
  78 }
  79
  80 static struct net_device *get_dpdev(const struct datapath *dp)
  81 {
  82         struct vport *local;
  83
  84         local = ovs_vport_ovsl(dp, OVSP_LOCAL);
  85         BUG_ON(!local);
  86         return local->dev;
  87 }
  88
  89 struct vport *ovs_netdev_link(struct vport *vport, const char *name)
  90 {
  91         int err;
  92
  93         vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), name);
  94         if (!vport->dev) {
  95                 err = -ENODEV;
  96                 goto error_free_vport;
  97         }
  98
  99         if (vport->dev->flags & IFF_LOOPBACK ||
 100             vport->dev->type != ARPHRD_ETHER ||
 101             ovs_is_internal_dev(vport->dev)) {
 102                 err = -EINVAL;
 103                 goto error_put;
 104         }
 105
 106         rtnl_lock();
 107         err = netdev_master_upper_dev_link(vport->dev,
 108                                            get_dpdev(vport->dp));
 109         if (err)
 110                 goto error_unlock;
 111
 112         err = netdev_rx_handler_register(vport->dev, netdev_frame_hook,
 113                                          vport);
 114         if (err)
 115                 goto error_master_upper_dev_unlink;
 116
 117         dev_disable_lro(vport->dev);
 118         dev_set_promiscuity(vport->dev, 1);
 119         vport->dev->priv_flags |= IFF_OVS_DATAPATH;
 120         rtnl_unlock();
 121
 122         return vport;
 123
 124 error_master_upper_dev_unlink:
 125         netdev_upper_dev_unlink(vport->dev, get_dpdev(vport->dp));
 126 error_unlock:
 127         rtnl_unlock();
 128 error_put:
 129         dev_put(vport->dev);
 130 error_free_vport:
 131         ovs_vport_free(vport);
 132         return ERR_PTR(err);
 133 }
 134 EXPORT_SYMBOL_GPL(ovs_netdev_link);
 135
 136 static struct vport *netdev_create(const struct vport_parms *parms)
 137 {
 138         struct vport *vport;
 139
 140         vport = ovs_vport_alloc(0, &ovs_netdev_vport_ops, parms);
 141         if (IS_ERR(vport))
 142                 return vport;
 143
 144         return ovs_netdev_link(vport, parms->name);
 145 }
 146
 147 static void vport_netdev_free(struct rcu_head *rcu)
 148 {
 149         struct vport *vport = container_of(rcu, struct vport, rcu);
 150
 151         if (vport->dev)
 152                 dev_put(vport->dev);
 153         ovs_vport_free(vport);
 154 }
 155
 156 void ovs_netdev_detach_dev(struct vport *vport)
 157 {
 158         ASSERT_RTNL();
 159         vport->dev->priv_flags &= ~IFF_OVS_DATAPATH;
 160         netdev_rx_handler_unregister(vport->dev);
 161         netdev_upper_dev_unlink(vport->dev,
 162                                 netdev_master_upper_dev_get(vport->dev));
 163         dev_set_promiscuity(vport->dev, -1);
 164 }
 165 EXPORT_SYMBOL_GPL(ovs_netdev_detach_dev);
 166
 167 static void netdev_destroy(struct vport *vport)
 168 {
 169         rtnl_lock();
 170         if (vport->dev->priv_flags & IFF_OVS_DATAPATH)
 171                 ovs_netdev_detach_dev(vport);
 172         rtnl_unlock();
 173
 174         call_rcu(&vport->rcu, vport_netdev_free);
 175 }
 176
 177 void ovs_netdev_tunnel_destroy(struct vport *vport)
 178 {
 179         rtnl_lock();
 180         if (vport->dev->priv_flags & IFF_OVS_DATAPATH)
 181                 ovs_netdev_detach_dev(vport);
 182
 183         /* We can be invoked by both explicit vport deletion and
 184          * underlying netdev deregistration; delete the link only
 185          * if it's not already shutting down.
 186          */
 187         if (vport->dev->reg_state == NETREG_REGISTERED)
 188                 rtnl_delete_link(vport->dev);
 189         dev_put(vport->dev);
 190         vport->dev = NULL;
 191         rtnl_unlock();
 192
 193         call_rcu(&vport->rcu, vport_netdev_free);
 194 }
 195 EXPORT_SYMBOL_GPL(ovs_netdev_tunnel_destroy);
 196
 197 /* Returns null if this device is not attached to a datapath. */
 198 struct vport *ovs_netdev_get_vport(struct net_device *dev)
 199 {
 200         if (likely(dev->priv_flags & IFF_OVS_DATAPATH))
 201                 return (struct vport *)
 202                         rcu_dereference_rtnl(dev->rx_handler_data);
 203         else
 204                 return NULL;
 205 }
 206
 207 static struct vport_ops ovs_netdev_vport_ops = {
 208         .type           = OVS_VPORT_TYPE_NETDEV,
 209         .create         = netdev_create,
 210         .destroy        = netdev_destroy,
 211         .send           = dev_queue_xmit,
 212 };
 213
 214 int __init ovs_netdev_init(void)
 215 {
 216         return ovs_vport_ops_register(&ovs_netdev_vport_ops);
 217 }
 218
 219 void ovs_netdev_exit(void)
 220 {
 221         ovs_vport_ops_unregister(&ovs_netdev_vport_ops);
 222 }