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 vport *vport, struct sk_buff *skb) 43 { 44 if (unlikely(!vport)) 45 goto error; 46 47 if (unlikely(skb_warn_if_lro(skb))) 48 goto error; 49 50 /* Make our own copy of the packet. Otherwise we will mangle the 51 * packet for anyone who came before us (e.g. tcpdump via AF_PACKET). 52 */ 53 skb = skb_share_check(skb, GFP_ATOMIC); 54 if (unlikely(!skb)) 55 return; 56 57 skb_push(skb, ETH_HLEN); 58 ovs_skb_postpush_rcsum(skb, skb->data, ETH_HLEN); 59 60 ovs_vport_receive(vport, skb, skb_tunnel_info(skb, AF_INET)); 61 return; 62 63 error: 64 kfree_skb(skb); 65 } 66 67 /* Called with rcu_read_lock and bottom-halves disabled. */ 68 static rx_handler_result_t netdev_frame_hook(struct sk_buff **pskb) 69 { 70 struct sk_buff *skb = *pskb; 71 struct vport *vport; 72 73 if (unlikely(skb->pkt_type == PACKET_LOOPBACK)) 74 return RX_HANDLER_PASS; 75 76 vport = ovs_netdev_get_vport(skb->dev); 77 78 netdev_port_receive(vport, skb); 79 80 return RX_HANDLER_CONSUMED; 81 } 82 83 static struct net_device *get_dpdev(const struct datapath *dp) 84 { 85 struct vport *local; 86 87 local = ovs_vport_ovsl(dp, OVSP_LOCAL); 88 BUG_ON(!local); 89 return local->dev; 90 } 91 92 struct vport *ovs_netdev_link(struct vport *vport, const char *name) 93 { 94 int err; 95 96 vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), name); 97 if (!vport->dev) { 98 err = -ENODEV; 99 goto error_free_vport; 100 } 101 102 if (vport->dev->flags & IFF_LOOPBACK || 103 vport->dev->type != ARPHRD_ETHER || 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)); 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 void ovs_vport_free_rcu(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 EXPORT_SYMBOL_GPL(ovs_vport_free_rcu); 159 160 void ovs_netdev_detach_dev(struct vport *vport) 161 { 162 ASSERT_RTNL(); 163 vport->dev->priv_flags &= ~IFF_OVS_DATAPATH; 164 netdev_rx_handler_unregister(vport->dev); 165 netdev_upper_dev_unlink(vport->dev, 166 netdev_master_upper_dev_get(vport->dev)); 167 dev_set_promiscuity(vport->dev, -1); 168 } 169 EXPORT_SYMBOL_GPL(ovs_netdev_detach_dev); 170 171 static void netdev_destroy(struct vport *vport) 172 { 173 rtnl_lock(); 174 if (vport->dev->priv_flags & IFF_OVS_DATAPATH) 175 ovs_netdev_detach_dev(vport); 176 rtnl_unlock(); 177 178 call_rcu(&vport->rcu, ovs_vport_free_rcu); 179 } 180 181 static unsigned int packet_length(const struct sk_buff *skb) 182 { 183 unsigned int length = skb->len - ETH_HLEN; 184 185 if (skb->protocol == htons(ETH_P_8021Q)) 186 length -= VLAN_HLEN; 187 188 return length; 189 } 190 191 int ovs_netdev_send(struct vport *vport, struct sk_buff *skb) 192 { 193 int mtu = vport->dev->mtu; 194 int len; 195 196 if (unlikely(packet_length(skb) > mtu && !skb_is_gso(skb))) { 197 net_warn_ratelimited("%s: dropped over-mtu packet: %d > %d\n", 198 vport->dev->name, 199 packet_length(skb), mtu); 200 goto drop; 201 } 202 203 skb->dev = vport->dev; 204 len = skb->len; 205 dev_queue_xmit(skb); 206 207 return len; 208 209 drop: 210 kfree_skb(skb); 211 return 0; 212 } 213 EXPORT_SYMBOL_GPL(ovs_netdev_send); 214 215 /* Returns null if this device is not attached to a datapath. */ 216 struct vport *ovs_netdev_get_vport(struct net_device *dev) 217 { 218 if (likely(dev->priv_flags & IFF_OVS_DATAPATH)) 219 return (struct vport *) 220 rcu_dereference_rtnl(dev->rx_handler_data); 221 else 222 return NULL; 223 } 224 225 static struct vport_ops ovs_netdev_vport_ops = { 226 .type = OVS_VPORT_TYPE_NETDEV, 227 .create = netdev_create, 228 .destroy = netdev_destroy, 229 .send = ovs_netdev_send, 230 }; 231 232 int __init ovs_netdev_init(void) 233 { 234 return ovs_vport_ops_register(&ovs_netdev_vport_ops); 235 } 236 237 void ovs_netdev_exit(void) 238 { 239 ovs_vport_ops_unregister(&ovs_netdev_vport_ops); 240 } 241