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 void internal_set_rx_headroom(struct net_device *dev, int new_hr)
142 {
143 	dev->needed_headroom = new_hr;
144 }
145 
146 static const struct net_device_ops internal_dev_netdev_ops = {
147 	.ndo_open = internal_dev_open,
148 	.ndo_stop = internal_dev_stop,
149 	.ndo_start_xmit = internal_dev_xmit,
150 	.ndo_set_mac_address = eth_mac_addr,
151 	.ndo_change_mtu = internal_dev_change_mtu,
152 	.ndo_get_stats64 = internal_get_stats,
153 	.ndo_set_rx_headroom = internal_set_rx_headroom,
154 };
155 
156 static struct rtnl_link_ops internal_dev_link_ops __read_mostly = {
157 	.kind = "openvswitch",
158 };
159 
160 static void do_setup(struct net_device *netdev)
161 {
162 	ether_setup(netdev);
163 
164 	netdev->netdev_ops = &internal_dev_netdev_ops;
165 
166 	netdev->priv_flags &= ~IFF_TX_SKB_SHARING;
167 	netdev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_OPENVSWITCH |
168 			      IFF_PHONY_HEADROOM | IFF_NO_QUEUE;
169 	netdev->destructor = internal_dev_destructor;
170 	netdev->ethtool_ops = &internal_dev_ethtool_ops;
171 	netdev->rtnl_link_ops = &internal_dev_link_ops;
172 
173 	netdev->features = NETIF_F_LLTX | NETIF_F_SG | NETIF_F_FRAGLIST |
174 			   NETIF_F_HIGHDMA | NETIF_F_HW_CSUM |
175 			   NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL;
176 
177 	netdev->vlan_features = netdev->features;
178 	netdev->hw_enc_features = netdev->features;
179 	netdev->features |= NETIF_F_HW_VLAN_CTAG_TX;
180 	netdev->hw_features = netdev->features & ~NETIF_F_LLTX;
181 
182 	eth_hw_addr_random(netdev);
183 }
184 
185 static struct vport *internal_dev_create(const struct vport_parms *parms)
186 {
187 	struct vport *vport;
188 	struct internal_dev *internal_dev;
189 	int err;
190 
191 	vport = ovs_vport_alloc(0, &ovs_internal_vport_ops, parms);
192 	if (IS_ERR(vport)) {
193 		err = PTR_ERR(vport);
194 		goto error;
195 	}
196 
197 	vport->dev = alloc_netdev(sizeof(struct internal_dev),
198 				  parms->name, NET_NAME_USER, do_setup);
199 	if (!vport->dev) {
200 		err = -ENOMEM;
201 		goto error_free_vport;
202 	}
203 	vport->dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
204 	if (!vport->dev->tstats) {
205 		err = -ENOMEM;
206 		goto error_free_netdev;
207 	}
208 	vport->dev->needed_headroom = vport->dp->max_headroom;
209 
210 	dev_net_set(vport->dev, ovs_dp_get_net(vport->dp));
211 	internal_dev = internal_dev_priv(vport->dev);
212 	internal_dev->vport = vport;
213 
214 	/* Restrict bridge port to current netns. */
215 	if (vport->port_no == OVSP_LOCAL)
216 		vport->dev->features |= NETIF_F_NETNS_LOCAL;
217 
218 	rtnl_lock();
219 	err = register_netdevice(vport->dev);
220 	if (err)
221 		goto error_unlock;
222 
223 	dev_set_promiscuity(vport->dev, 1);
224 	rtnl_unlock();
225 	netif_start_queue(vport->dev);
226 
227 	return vport;
228 
229 error_unlock:
230 	rtnl_unlock();
231 	free_percpu(vport->dev->tstats);
232 error_free_netdev:
233 	free_netdev(vport->dev);
234 error_free_vport:
235 	ovs_vport_free(vport);
236 error:
237 	return ERR_PTR(err);
238 }
239 
240 static void internal_dev_destroy(struct vport *vport)
241 {
242 	netif_stop_queue(vport->dev);
243 	rtnl_lock();
244 	dev_set_promiscuity(vport->dev, -1);
245 
246 	/* unregister_netdevice() waits for an RCU grace period. */
247 	unregister_netdevice(vport->dev);
248 	free_percpu(vport->dev->tstats);
249 	rtnl_unlock();
250 }
251 
252 static netdev_tx_t internal_dev_recv(struct sk_buff *skb)
253 {
254 	struct net_device *netdev = skb->dev;
255 	struct pcpu_sw_netstats *stats;
256 
257 	if (unlikely(!(netdev->flags & IFF_UP))) {
258 		kfree_skb(skb);
259 		netdev->stats.rx_dropped++;
260 		return NETDEV_TX_OK;
261 	}
262 
263 	skb_dst_drop(skb);
264 	nf_reset(skb);
265 	secpath_reset(skb);
266 
267 	skb->pkt_type = PACKET_HOST;
268 	skb->protocol = eth_type_trans(skb, netdev);
269 	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
270 
271 	stats = this_cpu_ptr(netdev->tstats);
272 	u64_stats_update_begin(&stats->syncp);
273 	stats->rx_packets++;
274 	stats->rx_bytes += skb->len;
275 	u64_stats_update_end(&stats->syncp);
276 
277 	netif_rx(skb);
278 	return NETDEV_TX_OK;
279 }
280 
281 static struct vport_ops ovs_internal_vport_ops = {
282 	.type		= OVS_VPORT_TYPE_INTERNAL,
283 	.create		= internal_dev_create,
284 	.destroy	= internal_dev_destroy,
285 	.send		= internal_dev_recv,
286 };
287 
288 int ovs_is_internal_dev(const struct net_device *netdev)
289 {
290 	return netdev->netdev_ops == &internal_dev_netdev_ops;
291 }
292 
293 struct vport *ovs_internal_dev_get_vport(struct net_device *netdev)
294 {
295 	if (!ovs_is_internal_dev(netdev))
296 		return NULL;
297 
298 	return internal_dev_priv(netdev)->vport;
299 }
300 
301 int ovs_internal_dev_rtnl_link_register(void)
302 {
303 	int err;
304 
305 	err = rtnl_link_register(&internal_dev_link_ops);
306 	if (err < 0)
307 		return err;
308 
309 	err = ovs_vport_ops_register(&ovs_internal_vport_ops);
310 	if (err < 0)
311 		rtnl_link_unregister(&internal_dev_link_ops);
312 
313 	return err;
314 }
315 
316 void ovs_internal_dev_rtnl_link_unregister(void)
317 {
318 	ovs_vport_ops_unregister(&ovs_internal_vport_ops);
319 	rtnl_link_unregister(&internal_dev_link_ops);
320 }
321