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 29 #include <net/llc.h> 30 31 #include "datapath.h" 32 #include "vport-internal_dev.h" 33 #include "vport-netdev.h" 34 35 /* Must be called with rcu_read_lock. */ 36 static void netdev_port_receive(struct vport *vport, struct sk_buff *skb) 37 { 38 if (unlikely(!vport)) { 39 kfree_skb(skb); 40 return; 41 } 42 43 /* Make our own copy of the packet. Otherwise we will mangle the 44 * packet for anyone who came before us (e.g. tcpdump via AF_PACKET). 45 * (No one comes after us, since we tell handle_bridge() that we took 46 * the packet.) */ 47 skb = skb_share_check(skb, GFP_ATOMIC); 48 if (unlikely(!skb)) 49 return; 50 51 skb_push(skb, ETH_HLEN); 52 ovs_vport_receive(vport, skb); 53 } 54 55 /* Called with rcu_read_lock and bottom-halves disabled. */ 56 static rx_handler_result_t netdev_frame_hook(struct sk_buff **pskb) 57 { 58 struct sk_buff *skb = *pskb; 59 struct vport *vport; 60 61 if (unlikely(skb->pkt_type == PACKET_LOOPBACK)) 62 return RX_HANDLER_PASS; 63 64 vport = ovs_netdev_get_vport(skb->dev); 65 66 netdev_port_receive(vport, skb); 67 68 return RX_HANDLER_CONSUMED; 69 } 70 71 static struct vport *netdev_create(const struct vport_parms *parms) 72 { 73 struct vport *vport; 74 struct netdev_vport *netdev_vport; 75 int err; 76 77 vport = ovs_vport_alloc(sizeof(struct netdev_vport), 78 &ovs_netdev_vport_ops, parms); 79 if (IS_ERR(vport)) { 80 err = PTR_ERR(vport); 81 goto error; 82 } 83 84 netdev_vport = netdev_vport_priv(vport); 85 86 netdev_vport->dev = dev_get_by_name(ovs_dp_get_net(vport->dp), parms->name); 87 if (!netdev_vport->dev) { 88 err = -ENODEV; 89 goto error_free_vport; 90 } 91 92 if (netdev_vport->dev->flags & IFF_LOOPBACK || 93 netdev_vport->dev->type != ARPHRD_ETHER || 94 ovs_is_internal_dev(netdev_vport->dev)) { 95 err = -EINVAL; 96 goto error_put; 97 } 98 99 err = netdev_rx_handler_register(netdev_vport->dev, netdev_frame_hook, 100 vport); 101 if (err) 102 goto error_put; 103 104 dev_set_promiscuity(netdev_vport->dev, 1); 105 netdev_vport->dev->priv_flags |= IFF_OVS_DATAPATH; 106 107 return vport; 108 109 error_put: 110 dev_put(netdev_vport->dev); 111 error_free_vport: 112 ovs_vport_free(vport); 113 error: 114 return ERR_PTR(err); 115 } 116 117 static void free_port_rcu(struct rcu_head *rcu) 118 { 119 struct netdev_vport *netdev_vport = container_of(rcu, 120 struct netdev_vport, rcu); 121 122 dev_put(netdev_vport->dev); 123 ovs_vport_free(vport_from_priv(netdev_vport)); 124 } 125 126 static void netdev_destroy(struct vport *vport) 127 { 128 struct netdev_vport *netdev_vport = netdev_vport_priv(vport); 129 130 netdev_vport->dev->priv_flags &= ~IFF_OVS_DATAPATH; 131 netdev_rx_handler_unregister(netdev_vport->dev); 132 dev_set_promiscuity(netdev_vport->dev, -1); 133 134 call_rcu(&netdev_vport->rcu, free_port_rcu); 135 } 136 137 const char *ovs_netdev_get_name(const struct vport *vport) 138 { 139 const struct netdev_vport *netdev_vport = netdev_vport_priv(vport); 140 return netdev_vport->dev->name; 141 } 142 143 int ovs_netdev_get_ifindex(const struct vport *vport) 144 { 145 const struct netdev_vport *netdev_vport = netdev_vport_priv(vport); 146 return netdev_vport->dev->ifindex; 147 } 148 149 static unsigned int packet_length(const struct sk_buff *skb) 150 { 151 unsigned int length = skb->len - ETH_HLEN; 152 153 if (skb->protocol == htons(ETH_P_8021Q)) 154 length -= VLAN_HLEN; 155 156 return length; 157 } 158 159 static int netdev_send(struct vport *vport, struct sk_buff *skb) 160 { 161 struct netdev_vport *netdev_vport = netdev_vport_priv(vport); 162 int mtu = netdev_vport->dev->mtu; 163 int len; 164 165 if (unlikely(packet_length(skb) > mtu && !skb_is_gso(skb))) { 166 net_warn_ratelimited("%s: dropped over-mtu packet: %d > %d\n", 167 netdev_vport->dev->name, 168 packet_length(skb), mtu); 169 goto error; 170 } 171 172 if (unlikely(skb_warn_if_lro(skb))) 173 goto error; 174 175 skb->dev = netdev_vport->dev; 176 len = skb->len; 177 dev_queue_xmit(skb); 178 179 return len; 180 181 error: 182 kfree_skb(skb); 183 ovs_vport_record_error(vport, VPORT_E_TX_DROPPED); 184 return 0; 185 } 186 187 /* Returns null if this device is not attached to a datapath. */ 188 struct vport *ovs_netdev_get_vport(struct net_device *dev) 189 { 190 if (likely(dev->priv_flags & IFF_OVS_DATAPATH)) 191 return (struct vport *) 192 rcu_dereference_rtnl(dev->rx_handler_data); 193 else 194 return NULL; 195 } 196 197 const struct vport_ops ovs_netdev_vport_ops = { 198 .type = OVS_VPORT_TYPE_NETDEV, 199 .create = netdev_create, 200 .destroy = netdev_destroy, 201 .get_name = ovs_netdev_get_name, 202 .get_ifindex = ovs_netdev_get_ifindex, 203 .send = netdev_send, 204 }; 205