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         if (skb->dev->type == ARPHRD_ETHER) {
  61                 skb_push(skb, ETH_HLEN);
  62                 skb_postpush_rcsum(skb, skb->data, ETH_HLEN);
  63         }
  64         ovs_vport_receive(vport, skb, skb_tunnel_info(skb));
  65         return;
  66 error:
  67         kfree_skb(skb);
  68 }
  69
  70 /* Called with rcu_read_lock and bottom-halves disabled. */
  71 static rx_handler_result_t netdev_frame_hook(struct sk_buff **pskb)
  72 {
  73         struct sk_buff *skb = *pskb;
  74
  75         if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
  76                 return RX_HANDLER_PASS;
  77
  78         netdev_port_receive(skb);
  79         return RX_HANDLER_CONSUMED;
  80 }
  81
  82 static struct net_device *get_dpdev(const struct datapath *dp)
  83 {
  84         struct vport *local;
  85
  86         local = ovs_vport_ovsl(dp, OVSP_LOCAL);
  87         BUG_ON(!local);
  88         return local->dev;
  89 }
  90
  91 struct vport *ovs_netdev_link(struct vport *vport, const char *name)
  92 {
  93         int err;
  94
  95         vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), name);
  96         if (!vport->dev) {
  97                 err = -ENODEV;
  98                 goto error_free_vport;
  99         }
 100
 101         if (vport->dev->flags & IFF_LOOPBACK ||
 102             (vport->dev->type != ARPHRD_ETHER &&
 103              vport->dev->type != ARPHRD_NONE) ||
 104             ovs_is_internal_dev(vport->dev)) {
 105                 err = -EINVAL;
 106                 goto error_put;
 107         }
 108
 109         rtnl_lock();
 110         err = netdev_master_upper_dev_link(vport->dev,
 111                                            get_dpdev(vport->dp), NULL, NULL);
 112         if (err)
 113                 goto error_unlock;
 114
 115         err = netdev_rx_handler_register(vport->dev, netdev_frame_hook,
 116                                          vport);
 117         if (err)
 118                 goto error_master_upper_dev_unlink;
 119
 120         dev_disable_lro(vport->dev);
 121         dev_set_promiscuity(vport->dev, 1);
 122         vport->dev->priv_flags |= IFF_OVS_DATAPATH;
 123         rtnl_unlock();
 124
 125         return vport;
 126
 127 error_master_upper_dev_unlink:
 128         netdev_upper_dev_unlink(vport->dev, get_dpdev(vport->dp));
 129 error_unlock:
 130         rtnl_unlock();
 131 error_put:
 132         dev_put(vport->dev);
 133 error_free_vport:
 134         ovs_vport_free(vport);
 135         return ERR_PTR(err);
 136 }
 137 EXPORT_SYMBOL_GPL(ovs_netdev_link);
 138
 139 static struct vport *netdev_create(const struct vport_parms *parms)
 140 {
 141         struct vport *vport;
 142
 143         vport = ovs_vport_alloc(0, &ovs_netdev_vport_ops, parms);
 144         if (IS_ERR(vport))
 145                 return vport;
 146
 147         return ovs_netdev_link(vport, parms->name);
 148 }
 149
 150 static void vport_netdev_free(struct rcu_head *rcu)
 151 {
 152         struct vport *vport = container_of(rcu, struct vport, rcu);
 153
 154         if (vport->dev)
 155                 dev_put(vport->dev);
 156         ovs_vport_free(vport);
 157 }
 158
 159 void ovs_netdev_detach_dev(struct vport *vport)
 160 {
 161         ASSERT_RTNL();
 162         vport->dev->priv_flags &= ~IFF_OVS_DATAPATH;
 163         netdev_rx_handler_unregister(vport->dev);
 164         netdev_upper_dev_unlink(vport->dev,
 165                                 netdev_master_upper_dev_get(vport->dev));
 166         dev_set_promiscuity(vport->dev, -1);
 167 }
 168
 169 static void netdev_destroy(struct vport *vport)
 170 {
 171         rtnl_lock();
 172         if (vport->dev->priv_flags & IFF_OVS_DATAPATH)
 173                 ovs_netdev_detach_dev(vport);
 174         rtnl_unlock();
 175
 176         call_rcu(&vport->rcu, vport_netdev_free);
 177 }
 178
 179 void ovs_netdev_tunnel_destroy(struct vport *vport)
 180 {
 181         rtnl_lock();
 182         if (vport->dev->priv_flags & IFF_OVS_DATAPATH)
 183                 ovs_netdev_detach_dev(vport);
 184
 185         /* We can be invoked by both explicit vport deletion and
 186          * underlying netdev deregistration; delete the link only
 187          * if it's not already shutting down.
 188          */
 189         if (vport->dev->reg_state == NETREG_REGISTERED)
 190                 rtnl_delete_link(vport->dev);
 191         dev_put(vport->dev);
 192         vport->dev = NULL;
 193         rtnl_unlock();
 194
 195         call_rcu(&vport->rcu, vport_netdev_free);
 196 }
 197 EXPORT_SYMBOL_GPL(ovs_netdev_tunnel_destroy);
 198
 199 /* Returns null if this device is not attached to a datapath. */
 200 struct vport *ovs_netdev_get_vport(struct net_device *dev)
 201 {
 202         if (likely(dev->priv_flags & IFF_OVS_DATAPATH))
 203                 return (struct vport *)
 204                         rcu_dereference_rtnl(dev->rx_handler_data);
 205         else
 206                 return NULL;
 207 }
 208
 209 static struct vport_ops ovs_netdev_vport_ops = {
 210         .type           = OVS_VPORT_TYPE_NETDEV,
 211         .create         = netdev_create,
 212         .destroy        = netdev_destroy,
 213         .send           = dev_queue_xmit,
 214 };
 215
 216 int __init ovs_netdev_init(void)
 217 {
 218         return ovs_vport_ops_register(&ovs_netdev_vport_ops);
 219 }
 220
 221 void ovs_netdev_exit(void)
 222 {
 223         ovs_vport_ops_unregister(&ovs_netdev_vport_ops);
 224 }