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 #include <linux/hardirq.h>
20 #include <linux/if_vlan.h>
21 #include <linux/kernel.h>
22 #include <linux/netdevice.h>
23 #include <linux/etherdevice.h>
24 #include <linux/ethtool.h>
25 #include <linux/skbuff.h>
26 
27 #include <net/dst.h>
28 #include <net/xfrm.h>
29 #include <net/rtnetlink.h>
30 
31 #include "datapath.h"
32 #include "vport-internal_dev.h"
33 #include "vport-netdev.h"
34 
35 struct internal_dev {
36 	struct vport *vport;
37 };
38 
39 static struct vport_ops ovs_internal_vport_ops;
40 
41 static struct internal_dev *internal_dev_priv(struct net_device *netdev)
42 {
43 	return netdev_priv(netdev);
44 }
45 
46 /* Called with rcu_read_lock_bh. */
47 static int internal_dev_xmit(struct sk_buff *skb, struct net_device *netdev)
48 {
49 	int len, err;
50 
51 	len = skb->len;
52 	rcu_read_lock();
53 	err = ovs_vport_receive(internal_dev_priv(netdev)->vport, skb, NULL);
54 	rcu_read_unlock();
55 
56 	if (likely(!err)) {
57 		struct pcpu_sw_netstats *tstats = this_cpu_ptr(netdev->tstats);
58 
59 		u64_stats_update_begin(&tstats->syncp);
60 		tstats->tx_bytes += len;
61 		tstats->tx_packets++;
62 		u64_stats_update_end(&tstats->syncp);
63 	} else {
64 		netdev->stats.tx_errors++;
65 	}
66 	return 0;
67 }
68 
69 static int internal_dev_open(struct net_device *netdev)
70 {
71 	netif_start_queue(netdev);
72 	return 0;
73 }
74 
75 static int internal_dev_stop(struct net_device *netdev)
76 {
77 	netif_stop_queue(netdev);
78 	return 0;
79 }
80 
81 static void internal_dev_getinfo(struct net_device *netdev,
82 				 struct ethtool_drvinfo *info)
83 {
84 	strlcpy(info->driver, "openvswitch", sizeof(info->driver));
85 }
86 
87 static const struct ethtool_ops internal_dev_ethtool_ops = {
88 	.get_drvinfo	= internal_dev_getinfo,
89 	.get_link	= ethtool_op_get_link,
90 };
91 
92 static int internal_dev_change_mtu(struct net_device *netdev, int new_mtu)
93 {
94 	if (new_mtu < 68)
95 		return -EINVAL;
96 
97 	netdev->mtu = new_mtu;
98 	return 0;
99 }
100 
101 static void internal_dev_destructor(struct net_device *dev)
102 {
103 	struct vport *vport = ovs_internal_dev_get_vport(dev);
104 
105 	ovs_vport_free(vport);
106 	free_netdev(dev);
107 }
108 
109 static struct rtnl_link_stats64 *
110 internal_get_stats(struct net_device *dev, struct rtnl_link_stats64 *stats)
111 {
112 	int i;
113 
114 	memset(stats, 0, sizeof(*stats));
115 	stats->rx_errors  = dev->stats.rx_errors;
116 	stats->tx_errors  = dev->stats.tx_errors;
117 	stats->tx_dropped = dev->stats.tx_dropped;
118 	stats->rx_dropped = dev->stats.rx_dropped;
119 
120 	for_each_possible_cpu(i) {
121 		const struct pcpu_sw_netstats *percpu_stats;
122 		struct pcpu_sw_netstats local_stats;
123 		unsigned int start;
124 
125 		percpu_stats = per_cpu_ptr(dev->tstats, i);
126 
127 		do {
128 			start = u64_stats_fetch_begin_irq(&percpu_stats->syncp);
129 			local_stats = *percpu_stats;
130 		} while (u64_stats_fetch_retry_irq(&percpu_stats->syncp, start));
131 
132 		stats->rx_bytes         += local_stats.rx_bytes;
133 		stats->rx_packets       += local_stats.rx_packets;
134 		stats->tx_bytes         += local_stats.tx_bytes;
135 		stats->tx_packets       += local_stats.tx_packets;
136 	}
137 
138 	return stats;
139 }
140 
141 static const struct net_device_ops internal_dev_netdev_ops = {
142 	.ndo_open = internal_dev_open,
143 	.ndo_stop = internal_dev_stop,
144 	.ndo_start_xmit = internal_dev_xmit,
145 	.ndo_set_mac_address = eth_mac_addr,
146 	.ndo_change_mtu = internal_dev_change_mtu,
147 	.ndo_get_stats64 = internal_get_stats,
148 };
149 
150 static struct rtnl_link_ops internal_dev_link_ops __read_mostly = {
151 	.kind = "openvswitch",
152 };
153 
154 static void do_setup(struct net_device *netdev)
155 {
156 	ether_setup(netdev);
157 
158 	netdev->netdev_ops = &internal_dev_netdev_ops;
159 
160 	netdev->priv_flags &= ~IFF_TX_SKB_SHARING;
161 	netdev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_OPENVSWITCH;
162 	netdev->destructor = internal_dev_destructor;
163 	netdev->ethtool_ops = &internal_dev_ethtool_ops;
164 	netdev->rtnl_link_ops = &internal_dev_link_ops;
165 	netdev->tx_queue_len = 0;
166 
167 	netdev->features = NETIF_F_LLTX | NETIF_F_SG | NETIF_F_FRAGLIST |
168 			   NETIF_F_HIGHDMA | NETIF_F_HW_CSUM |
169 			   NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL;
170 
171 	netdev->vlan_features = netdev->features;
172 	netdev->hw_enc_features = netdev->features;
173 	netdev->features |= NETIF_F_HW_VLAN_CTAG_TX;
174 	netdev->hw_features = netdev->features & ~NETIF_F_LLTX;
175 
176 	eth_hw_addr_random(netdev);
177 }
178 
179 static struct vport *internal_dev_create(const struct vport_parms *parms)
180 {
181 	struct vport *vport;
182 	struct internal_dev *internal_dev;
183 	int err;
184 
185 	vport = ovs_vport_alloc(0, &ovs_internal_vport_ops, parms);
186 	if (IS_ERR(vport)) {
187 		err = PTR_ERR(vport);
188 		goto error;
189 	}
190 
191 	vport->dev = alloc_netdev(sizeof(struct internal_dev),
192 				  parms->name, NET_NAME_UNKNOWN, do_setup);
193 	if (!vport->dev) {
194 		err = -ENOMEM;
195 		goto error_free_vport;
196 	}
197 	vport->dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
198 	if (!vport->dev->tstats) {
199 		err = -ENOMEM;
200 		goto error_free_netdev;
201 	}
202 
203 	dev_net_set(vport->dev, ovs_dp_get_net(vport->dp));
204 	internal_dev = internal_dev_priv(vport->dev);
205 	internal_dev->vport = vport;
206 
207 	/* Restrict bridge port to current netns. */
208 	if (vport->port_no == OVSP_LOCAL)
209 		vport->dev->features |= NETIF_F_NETNS_LOCAL;
210 
211 	rtnl_lock();
212 	err = register_netdevice(vport->dev);
213 	if (err)
214 		goto error_unlock;
215 
216 	dev_set_promiscuity(vport->dev, 1);
217 	rtnl_unlock();
218 	netif_start_queue(vport->dev);
219 
220 	return vport;
221 
222 error_unlock:
223 	rtnl_unlock();
224 	free_percpu(vport->dev->tstats);
225 error_free_netdev:
226 	free_netdev(vport->dev);
227 error_free_vport:
228 	ovs_vport_free(vport);
229 error:
230 	return ERR_PTR(err);
231 }
232 
233 static void internal_dev_destroy(struct vport *vport)
234 {
235 	netif_stop_queue(vport->dev);
236 	rtnl_lock();
237 	dev_set_promiscuity(vport->dev, -1);
238 
239 	/* unregister_netdevice() waits for an RCU grace period. */
240 	unregister_netdevice(vport->dev);
241 	free_percpu(vport->dev->tstats);
242 	rtnl_unlock();
243 }
244 
245 static netdev_tx_t internal_dev_recv(struct sk_buff *skb)
246 {
247 	struct net_device *netdev = skb->dev;
248 	struct pcpu_sw_netstats *stats;
249 
250 	if (unlikely(!(netdev->flags & IFF_UP))) {
251 		kfree_skb(skb);
252 		netdev->stats.rx_dropped++;
253 		return NETDEV_TX_OK;
254 	}
255 
256 	skb_dst_drop(skb);
257 	nf_reset(skb);
258 	secpath_reset(skb);
259 
260 	skb->pkt_type = PACKET_HOST;
261 	skb->protocol = eth_type_trans(skb, netdev);
262 	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
263 
264 	stats = this_cpu_ptr(netdev->tstats);
265 	u64_stats_update_begin(&stats->syncp);
266 	stats->rx_packets++;
267 	stats->rx_bytes += skb->len;
268 	u64_stats_update_end(&stats->syncp);
269 
270 	netif_rx(skb);
271 	return NETDEV_TX_OK;
272 }
273 
274 static struct vport_ops ovs_internal_vport_ops = {
275 	.type		= OVS_VPORT_TYPE_INTERNAL,
276 	.create		= internal_dev_create,
277 	.destroy	= internal_dev_destroy,
278 	.send		= internal_dev_recv,
279 };
280 
281 int ovs_is_internal_dev(const struct net_device *netdev)
282 {
283 	return netdev->netdev_ops == &internal_dev_netdev_ops;
284 }
285 
286 struct vport *ovs_internal_dev_get_vport(struct net_device *netdev)
287 {
288 	if (!ovs_is_internal_dev(netdev))
289 		return NULL;
290 
291 	return internal_dev_priv(netdev)->vport;
292 }
293 
294 int ovs_internal_dev_rtnl_link_register(void)
295 {
296 	int err;
297 
298 	err = rtnl_link_register(&internal_dev_link_ops);
299 	if (err < 0)
300 		return err;
301 
302 	err = ovs_vport_ops_register(&ovs_internal_vport_ops);
303 	if (err < 0)
304 		rtnl_link_unregister(&internal_dev_link_ops);
305 
306 	return err;
307 }
308 
309 void ovs_internal_dev_rtnl_link_unregister(void)
310 {
311 	ovs_vport_ops_unregister(&ovs_internal_vport_ops);
312 	rtnl_link_unregister(&internal_dev_link_ops);
313 }
314