datapath/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 "gso.h"
  36 #include "vport.h"
  37 #include "vport-internal_dev.h"
  38 #include "vport-netdev.h"
  39
  40 static struct vport_ops ovs_netdev_vport_ops;
  41
  42 /* Must be called with rcu_read_lock. */
  43 void netdev_port_receive(struct sk_buff *skb, struct ip_tunnel_info *tun_info)
  44 {
  45         struct vport *vport;
  46
  47         vport = ovs_netdev_get_vport(skb->dev);
  48         if (unlikely(!vport))
  49                 goto error;
  50
  51         if (unlikely(skb_warn_if_lro(skb)))
  52                 goto error;
  53
  54         /* Make our own copy of the packet.  Otherwise we will mangle the
  55          * packet for anyone who came before us (e.g. tcpdump via AF_PACKET).
  56          */
  57         skb = skb_share_check(skb, GFP_ATOMIC);
  58         if (unlikely(!skb))
  59                 return;
  60
  61         if (skb->dev->type == ARPHRD_ETHER) {
  62                 skb_push(skb, ETH_HLEN);
  63                 skb_postpush_rcsum(skb, skb->data, ETH_HLEN);
  64         }
  65         ovs_vport_receive(vport, skb, tun_info);
  66         return;
  67 error:
  68         kfree_skb(skb);
  69 }
  70
  71 /* Called with rcu_read_lock and bottom-halves disabled. */
  72 static rx_handler_result_t netdev_frame_hook(struct sk_buff **pskb)
  73 {
  74         struct sk_buff *skb = *pskb;
  75
  76         if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
  77                 return RX_HANDLER_PASS;
  78
  79 #ifndef USE_UPSTREAM_TUNNEL
  80         netdev_port_receive(skb, NULL);
  81 #else
  82         netdev_port_receive(skb, skb_tunnel_info(skb));
  83 #endif
  84         return RX_HANDLER_CONSUMED;
  85 }
  86
  87 static struct net_device *get_dpdev(const struct datapath *dp)
  88 {
  89         struct vport *local;
  90
  91         local = ovs_vport_ovsl(dp, OVSP_LOCAL);
  92         BUG_ON(!local);
  93         return local->dev;
  94 }
  95
  96 struct vport *ovs_netdev_link(struct vport *vport, const char *name)
  97 {
  98         int err;
  99
 100         vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), name);
 101         if (!vport->dev) {
 102                 err = -ENODEV;
 103                 goto error_free_vport;
 104         }
 105
 106         if (vport->dev->flags & IFF_LOOPBACK ||
 107             (vport->dev->type != ARPHRD_ETHER &&
 108              vport->dev->type != ARPHRD_NONE) ||
 109             ovs_is_internal_dev(vport->dev)) {
 110                 err = -EINVAL;
 111                 goto error_put;
 112         }
 113
 114         rtnl_lock();
 115         err = netdev_master_upper_dev_link(vport->dev,
 116                                            get_dpdev(vport->dp),
 117                                            NULL, NULL, NULL);
 118         if (err)
 119                 goto error_unlock;
 120
 121         err = netdev_rx_handler_register(vport->dev, netdev_frame_hook,
 122                                          vport);
 123         if (err)
 124                 goto error_master_upper_dev_unlink;
 125
 126         dev_disable_lro(vport->dev);
 127         dev_set_promiscuity(vport->dev, 1);
 128         vport->dev->priv_flags |= IFF_OVS_DATAPATH;
 129         rtnl_unlock();
 130
 131         return vport;
 132
 133 error_master_upper_dev_unlink:
 134         netdev_upper_dev_unlink(vport->dev, get_dpdev(vport->dp));
 135 error_unlock:
 136         rtnl_unlock();
 137 error_put:
 138         dev_put(vport->dev);
 139 error_free_vport:
 140         ovs_vport_free(vport);
 141         return ERR_PTR(err);
 142 }
 143 EXPORT_SYMBOL_GPL(ovs_netdev_link);
 144
 145 static struct vport *netdev_create(const struct vport_parms *parms)
 146 {
 147         struct vport *vport;
 148
 149         vport = ovs_vport_alloc(0, &ovs_netdev_vport_ops, parms);
 150         if (IS_ERR(vport))
 151                 return vport;
 152
 153         return ovs_netdev_link(vport, parms->name);
 154 }
 155
 156 static void vport_netdev_free(struct rcu_head *rcu)
 157 {
 158         struct vport *vport = container_of(rcu, struct vport, rcu);
 159
 160         if (vport->dev)
 161                 dev_put(vport->dev);
 162         ovs_vport_free(vport);
 163 }
 164
 165 void ovs_netdev_detach_dev(struct vport *vport)
 166 {
 167         ASSERT_RTNL();
 168         vport->dev->priv_flags &= ~IFF_OVS_DATAPATH;
 169         netdev_rx_handler_unregister(vport->dev);
 170         netdev_upper_dev_unlink(vport->dev,
 171                                 netdev_master_upper_dev_get(vport->dev));
 172         dev_set_promiscuity(vport->dev, -1);
 173 }
 174
 175 static void netdev_destroy(struct vport *vport)
 176 {
 177         rtnl_lock();
 178         if (vport->dev->priv_flags & IFF_OVS_DATAPATH)
 179                 ovs_netdev_detach_dev(vport);
 180         rtnl_unlock();
 181
 182         call_rcu(&vport->rcu, vport_netdev_free);
 183 }
 184
 185 void ovs_netdev_tunnel_destroy(struct vport *vport)
 186 {
 187         rtnl_lock();
 188         if (vport->dev->priv_flags & IFF_OVS_DATAPATH)
 189                 ovs_netdev_detach_dev(vport);
 190
 191         /* We can be invoked by both explicit vport deletion and
 192          * underlying netdev deregistration; delete the link only
 193          * if it's not already shutting down.
 194          */
 195         if (vport->dev->reg_state == NETREG_REGISTERED)
 196                 rtnl_delete_link(vport->dev);
 197         dev_put(vport->dev);
 198         vport->dev = NULL;
 199         rtnl_unlock();
 200
 201         call_rcu(&vport->rcu, vport_netdev_free);
 202 }
 203 EXPORT_SYMBOL_GPL(ovs_netdev_tunnel_destroy);
 204
 205 /* Returns null if this device is not attached to a datapath. */
 206 struct vport *ovs_netdev_get_vport(struct net_device *dev)
 207 {
 208         if (likely(dev->priv_flags & IFF_OVS_DATAPATH))
 209                 return (struct vport *)
 210                         rcu_dereference_rtnl(dev->rx_handler_data);
 211         else
 212                 return NULL;
 213 }
 214
 215 static struct vport_ops ovs_netdev_vport_ops = {
 216         .type           = OVS_VPORT_TYPE_NETDEV,
 217         .create         = netdev_create,
 218         .destroy        = netdev_destroy,
 219         .send           = dev_queue_xmit,
 220 };
 221
 222 int __init ovs_netdev_init(void)
 223 {
 224         return ovs_vport_ops_register(&ovs_netdev_vport_ops);
 225 }
 226
 227 void ovs_netdev_exit(void)
 228 {
 229         ovs_vport_ops_unregister(&ovs_netdev_vport_ops);
 230 }