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