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 /* Early release so we can unregister the device */ 184 dev_put(vport->dev); 185 rtnl_delete_link(vport->dev); 186 vport->dev = NULL; 187 rtnl_unlock(); 188 189 call_rcu(&vport->rcu, vport_netdev_free); 190 } 191 EXPORT_SYMBOL_GPL(ovs_netdev_tunnel_destroy); 192 193 static unsigned int packet_length(const struct sk_buff *skb) 194 { 195 unsigned int length = skb->len - ETH_HLEN; 196 197 if (skb->protocol == htons(ETH_P_8021Q)) 198 length -= VLAN_HLEN; 199 200 return length; 201 } 202 203 void ovs_netdev_send(struct vport *vport, struct sk_buff *skb) 204 { 205 int mtu = vport->dev->mtu; 206 207 if (unlikely(packet_length(skb) > mtu && !skb_is_gso(skb))) { 208 net_warn_ratelimited("%s: dropped over-mtu packet: %d > %d\n", 209 vport->dev->name, 210 packet_length(skb), mtu); 211 vport->dev->stats.tx_errors++; 212 goto drop; 213 } 214 215 skb->dev = vport->dev; 216 dev_queue_xmit(skb); 217 return; 218 219 drop: 220 kfree_skb(skb); 221 } 222 EXPORT_SYMBOL_GPL(ovs_netdev_send); 223 224 /* Returns null if this device is not attached to a datapath. */ 225 struct vport *ovs_netdev_get_vport(struct net_device *dev) 226 { 227 if (likely(dev->priv_flags & IFF_OVS_DATAPATH)) 228 return (struct vport *) 229 rcu_dereference_rtnl(dev->rx_handler_data); 230 else 231 return NULL; 232 } 233 234 static struct vport_ops ovs_netdev_vport_ops = { 235 .type = OVS_VPORT_TYPE_NETDEV, 236 .create = netdev_create, 237 .destroy = netdev_destroy, 238 .send = ovs_netdev_send, 239 }; 240 241 int __init ovs_netdev_init(void) 242 { 243 return ovs_vport_ops_register(&ovs_netdev_vport_ops); 244 } 245 246 void ovs_netdev_exit(void) 247 { 248 ovs_vport_ops_unregister(&ovs_netdev_vport_ops); 249 } 250