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 void internal_dev_destructor(struct net_device *dev)
93 {
94 	struct vport *vport = ovs_internal_dev_get_vport(dev);
95 
96 	ovs_vport_free(vport);
97 }
98 
99 static void
100 internal_get_stats(struct net_device *dev, struct rtnl_link_stats64 *stats)
101 {
102 	int i;
103 
104 	memset(stats, 0, sizeof(*stats));
105 	stats->rx_errors  = dev->stats.rx_errors;
106 	stats->tx_errors  = dev->stats.tx_errors;
107 	stats->tx_dropped = dev->stats.tx_dropped;
108 	stats->rx_dropped = dev->stats.rx_dropped;
109 
110 	for_each_possible_cpu(i) {
111 		const struct pcpu_sw_netstats *percpu_stats;
112 		struct pcpu_sw_netstats local_stats;
113 		unsigned int start;
114 
115 		percpu_stats = per_cpu_ptr(dev->tstats, i);
116 
117 		do {
118 			start = u64_stats_fetch_begin_irq(&percpu_stats->syncp);
119 			local_stats = *percpu_stats;
120 		} while (u64_stats_fetch_retry_irq(&percpu_stats->syncp, start));
121 
122 		stats->rx_bytes         += local_stats.rx_bytes;
123 		stats->rx_packets       += local_stats.rx_packets;
124 		stats->tx_bytes         += local_stats.tx_bytes;
125 		stats->tx_packets       += local_stats.tx_packets;
126 	}
127 }
128 
129 static void internal_set_rx_headroom(struct net_device *dev, int new_hr)
130 {
131 	dev->needed_headroom = new_hr < 0 ? 0 : new_hr;
132 }
133 
134 static const struct net_device_ops internal_dev_netdev_ops = {
135 	.ndo_open = internal_dev_open,
136 	.ndo_stop = internal_dev_stop,
137 	.ndo_start_xmit = internal_dev_xmit,
138 	.ndo_set_mac_address = eth_mac_addr,
139 	.ndo_get_stats64 = internal_get_stats,
140 	.ndo_set_rx_headroom = internal_set_rx_headroom,
141 };
142 
143 static struct rtnl_link_ops internal_dev_link_ops __read_mostly = {
144 	.kind = "openvswitch",
145 };
146 
147 static void do_setup(struct net_device *netdev)
148 {
149 	ether_setup(netdev);
150 
151 	netdev->max_mtu = ETH_MAX_MTU;
152 
153 	netdev->netdev_ops = &internal_dev_netdev_ops;
154 
155 	netdev->priv_flags &= ~IFF_TX_SKB_SHARING;
156 	netdev->priv_flags |= IFF_LIVE_ADDR_CHANGE | IFF_OPENVSWITCH |
157 			      IFF_PHONY_HEADROOM | IFF_NO_QUEUE;
158 	netdev->needs_free_netdev = true;
159 	netdev->priv_destructor = internal_dev_destructor;
160 	netdev->ethtool_ops = &internal_dev_ethtool_ops;
161 	netdev->rtnl_link_ops = &internal_dev_link_ops;
162 
163 	netdev->features = NETIF_F_LLTX | NETIF_F_SG | NETIF_F_FRAGLIST |
164 			   NETIF_F_HIGHDMA | NETIF_F_HW_CSUM |
165 			   NETIF_F_GSO_SOFTWARE | NETIF_F_GSO_ENCAP_ALL;
166 
167 	netdev->vlan_features = netdev->features;
168 	netdev->hw_enc_features = netdev->features;
169 	netdev->features |= NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_STAG_TX;
170 	netdev->hw_features = netdev->features & ~NETIF_F_LLTX;
171 
172 	eth_hw_addr_random(netdev);
173 }
174 
175 static struct vport *internal_dev_create(const struct vport_parms *parms)
176 {
177 	struct vport *vport;
178 	struct internal_dev *internal_dev;
179 	int err;
180 
181 	vport = ovs_vport_alloc(0, &ovs_internal_vport_ops, parms);
182 	if (IS_ERR(vport)) {
183 		err = PTR_ERR(vport);
184 		goto error;
185 	}
186 
187 	vport->dev = alloc_netdev(sizeof(struct internal_dev),
188 				  parms->name, NET_NAME_USER, do_setup);
189 	if (!vport->dev) {
190 		err = -ENOMEM;
191 		goto error_free_vport;
192 	}
193 	vport->dev->tstats = netdev_alloc_pcpu_stats(struct pcpu_sw_netstats);
194 	if (!vport->dev->tstats) {
195 		err = -ENOMEM;
196 		goto error_free_netdev;
197 	}
198 	vport->dev->needed_headroom = vport->dp->max_headroom;
199 
200 	dev_net_set(vport->dev, ovs_dp_get_net(vport->dp));
201 	internal_dev = internal_dev_priv(vport->dev);
202 	internal_dev->vport = vport;
203 
204 	/* Restrict bridge port to current netns. */
205 	if (vport->port_no == OVSP_LOCAL)
206 		vport->dev->features |= NETIF_F_NETNS_LOCAL;
207 
208 	rtnl_lock();
209 	err = register_netdevice(vport->dev);
210 	if (err)
211 		goto error_unlock;
212 
213 	dev_set_promiscuity(vport->dev, 1);
214 	rtnl_unlock();
215 	netif_start_queue(vport->dev);
216 
217 	return vport;
218 
219 error_unlock:
220 	rtnl_unlock();
221 	free_percpu(vport->dev->tstats);
222 error_free_netdev:
223 	free_netdev(vport->dev);
224 error_free_vport:
225 	ovs_vport_free(vport);
226 error:
227 	return ERR_PTR(err);
228 }
229 
230 static void internal_dev_destroy(struct vport *vport)
231 {
232 	netif_stop_queue(vport->dev);
233 	rtnl_lock();
234 	dev_set_promiscuity(vport->dev, -1);
235 
236 	/* unregister_netdevice() waits for an RCU grace period. */
237 	unregister_netdevice(vport->dev);
238 	free_percpu(vport->dev->tstats);
239 	rtnl_unlock();
240 }
241 
242 static netdev_tx_t internal_dev_recv(struct sk_buff *skb)
243 {
244 	struct net_device *netdev = skb->dev;
245 	struct pcpu_sw_netstats *stats;
246 
247 	if (unlikely(!(netdev->flags & IFF_UP))) {
248 		kfree_skb(skb);
249 		netdev->stats.rx_dropped++;
250 		return NETDEV_TX_OK;
251 	}
252 
253 	skb_dst_drop(skb);
254 	nf_reset(skb);
255 	secpath_reset(skb);
256 
257 	skb->pkt_type = PACKET_HOST;
258 	skb->protocol = eth_type_trans(skb, netdev);
259 	skb_postpull_rcsum(skb, eth_hdr(skb), ETH_HLEN);
260 
261 	stats = this_cpu_ptr(netdev->tstats);
262 	u64_stats_update_begin(&stats->syncp);
263 	stats->rx_packets++;
264 	stats->rx_bytes += skb->len;
265 	u64_stats_update_end(&stats->syncp);
266 
267 	netif_rx(skb);
268 	return NETDEV_TX_OK;
269 }
270 
271 static struct vport_ops ovs_internal_vport_ops = {
272 	.type		= OVS_VPORT_TYPE_INTERNAL,
273 	.create		= internal_dev_create,
274 	.destroy	= internal_dev_destroy,
275 	.send		= internal_dev_recv,
276 };
277 
278 int ovs_is_internal_dev(const struct net_device *netdev)
279 {
280 	return netdev->netdev_ops == &internal_dev_netdev_ops;
281 }
282 
283 struct vport *ovs_internal_dev_get_vport(struct net_device *netdev)
284 {
285 	if (!ovs_is_internal_dev(netdev))
286 		return NULL;
287 
288 	return internal_dev_priv(netdev)->vport;
289 }
290 
291 int ovs_internal_dev_rtnl_link_register(void)
292 {
293 	int err;
294 
295 	err = rtnl_link_register(&internal_dev_link_ops);
296 	if (err < 0)
297 		return err;
298 
299 	err = ovs_vport_ops_register(&ovs_internal_vport_ops);
300 	if (err < 0)
301 		rtnl_link_unregister(&internal_dev_link_ops);
302 
303 	return err;
304 }
305 
306 void ovs_internal_dev_rtnl_link_unregister(void)
307 {
308 	ovs_vport_ops_unregister(&ovs_internal_vport_ops);
309 	rtnl_link_unregister(&internal_dev_link_ops);
310 }
311