bridge: allow creating bridge devices with netlink
[linux-3.10.git] / net / bridge / br_device.c
1 /*
2  *      Device handling code
3  *      Linux ethernet bridge
4  *
5  *      Authors:
6  *      Lennert Buytenhek               <buytenh@gnu.org>
7  *
8  *      This program is free software; you can redistribute it and/or
9  *      modify it under the terms of the GNU General Public License
10  *      as published by the Free Software Foundation; either version
11  *      2 of the License, or (at your option) any later version.
12  */
13
14 #include <linux/kernel.h>
15 #include <linux/netdevice.h>
16 #include <linux/netpoll.h>
17 #include <linux/etherdevice.h>
18 #include <linux/ethtool.h>
19 #include <linux/list.h>
20 #include <linux/netfilter_bridge.h>
21
22 #include <asm/uaccess.h>
23 #include "br_private.h"
24
25 /* net device transmit always called with BH disabled */
26 netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev)
27 {
28         struct net_bridge *br = netdev_priv(dev);
29         const unsigned char *dest = skb->data;
30         struct net_bridge_fdb_entry *dst;
31         struct net_bridge_mdb_entry *mdst;
32         struct br_cpu_netstats *brstats = this_cpu_ptr(br->stats);
33
34 #ifdef CONFIG_BRIDGE_NETFILTER
35         if (skb->nf_bridge && (skb->nf_bridge->mask & BRNF_BRIDGED_DNAT)) {
36                 br_nf_pre_routing_finish_bridge_slow(skb);
37                 return NETDEV_TX_OK;
38         }
39 #endif
40
41         u64_stats_update_begin(&brstats->syncp);
42         brstats->tx_packets++;
43         brstats->tx_bytes += skb->len;
44         u64_stats_update_end(&brstats->syncp);
45
46         BR_INPUT_SKB_CB(skb)->brdev = dev;
47
48         skb_reset_mac_header(skb);
49         skb_pull(skb, ETH_HLEN);
50
51         rcu_read_lock();
52         if (is_multicast_ether_addr(dest)) {
53                 if (unlikely(netpoll_tx_running(dev))) {
54                         br_flood_deliver(br, skb);
55                         goto out;
56                 }
57                 if (br_multicast_rcv(br, NULL, skb)) {
58                         kfree_skb(skb);
59                         goto out;
60                 }
61
62                 mdst = br_mdb_get(br, skb);
63                 if (mdst || BR_INPUT_SKB_CB_MROUTERS_ONLY(skb))
64                         br_multicast_deliver(mdst, skb);
65                 else
66                         br_flood_deliver(br, skb);
67         } else if ((dst = __br_fdb_get(br, dest)) != NULL)
68                 br_deliver(dst->dst, skb);
69         else
70                 br_flood_deliver(br, skb);
71
72 out:
73         rcu_read_unlock();
74         return NETDEV_TX_OK;
75 }
76
77 static int br_dev_init(struct net_device *dev)
78 {
79         struct net_bridge *br = netdev_priv(dev);
80
81         br->stats = alloc_percpu(struct br_cpu_netstats);
82         if (!br->stats)
83                 return -ENOMEM;
84
85         return 0;
86 }
87
88 static int br_dev_open(struct net_device *dev)
89 {
90         struct net_bridge *br = netdev_priv(dev);
91
92         netif_carrier_off(dev);
93
94         br_features_recompute(br);
95         netif_start_queue(dev);
96         br_stp_enable_bridge(br);
97         br_multicast_open(br);
98
99         return 0;
100 }
101
102 static void br_dev_set_multicast_list(struct net_device *dev)
103 {
104 }
105
106 static int br_dev_stop(struct net_device *dev)
107 {
108         struct net_bridge *br = netdev_priv(dev);
109
110         netif_carrier_off(dev);
111
112         br_stp_disable_bridge(br);
113         br_multicast_stop(br);
114
115         netif_stop_queue(dev);
116
117         return 0;
118 }
119
120 static struct rtnl_link_stats64 *br_get_stats64(struct net_device *dev,
121                                                 struct rtnl_link_stats64 *stats)
122 {
123         struct net_bridge *br = netdev_priv(dev);
124         struct br_cpu_netstats tmp, sum = { 0 };
125         unsigned int cpu;
126
127         for_each_possible_cpu(cpu) {
128                 unsigned int start;
129                 const struct br_cpu_netstats *bstats
130                         = per_cpu_ptr(br->stats, cpu);
131                 do {
132                         start = u64_stats_fetch_begin(&bstats->syncp);
133                         memcpy(&tmp, bstats, sizeof(tmp));
134                 } while (u64_stats_fetch_retry(&bstats->syncp, start));
135                 sum.tx_bytes   += tmp.tx_bytes;
136                 sum.tx_packets += tmp.tx_packets;
137                 sum.rx_bytes   += tmp.rx_bytes;
138                 sum.rx_packets += tmp.rx_packets;
139         }
140
141         stats->tx_bytes   = sum.tx_bytes;
142         stats->tx_packets = sum.tx_packets;
143         stats->rx_bytes   = sum.rx_bytes;
144         stats->rx_packets = sum.rx_packets;
145
146         return stats;
147 }
148
149 static int br_change_mtu(struct net_device *dev, int new_mtu)
150 {
151         struct net_bridge *br = netdev_priv(dev);
152         if (new_mtu < 68 || new_mtu > br_min_mtu(br))
153                 return -EINVAL;
154
155         dev->mtu = new_mtu;
156
157 #ifdef CONFIG_BRIDGE_NETFILTER
158         /* remember the MTU in the rtable for PMTU */
159         dst_metric_set(&br->fake_rtable.dst, RTAX_MTU, new_mtu);
160 #endif
161
162         return 0;
163 }
164
165 /* Allow setting mac address to any valid ethernet address. */
166 static int br_set_mac_address(struct net_device *dev, void *p)
167 {
168         struct net_bridge *br = netdev_priv(dev);
169         struct sockaddr *addr = p;
170
171         if (!is_valid_ether_addr(addr->sa_data))
172                 return -EINVAL;
173
174         spin_lock_bh(&br->lock);
175         memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
176         br_stp_change_bridge_id(br, addr->sa_data);
177         br->flags |= BR_SET_MAC_ADDR;
178         spin_unlock_bh(&br->lock);
179
180         return 0;
181 }
182
183 static void br_getinfo(struct net_device *dev, struct ethtool_drvinfo *info)
184 {
185         strcpy(info->driver, "bridge");
186         strcpy(info->version, BR_VERSION);
187         strcpy(info->fw_version, "N/A");
188         strcpy(info->bus_info, "N/A");
189 }
190
191 static int br_set_sg(struct net_device *dev, u32 data)
192 {
193         struct net_bridge *br = netdev_priv(dev);
194
195         if (data)
196                 br->feature_mask |= NETIF_F_SG;
197         else
198                 br->feature_mask &= ~NETIF_F_SG;
199
200         br_features_recompute(br);
201         return 0;
202 }
203
204 static int br_set_tso(struct net_device *dev, u32 data)
205 {
206         struct net_bridge *br = netdev_priv(dev);
207
208         if (data)
209                 br->feature_mask |= NETIF_F_TSO;
210         else
211                 br->feature_mask &= ~NETIF_F_TSO;
212
213         br_features_recompute(br);
214         return 0;
215 }
216
217 static int br_set_tx_csum(struct net_device *dev, u32 data)
218 {
219         struct net_bridge *br = netdev_priv(dev);
220
221         if (data)
222                 br->feature_mask |= NETIF_F_NO_CSUM;
223         else
224                 br->feature_mask &= ~NETIF_F_ALL_CSUM;
225
226         br_features_recompute(br);
227         return 0;
228 }
229
230 static int br_set_flags(struct net_device *netdev, u32 data)
231 {
232         return ethtool_op_set_flags(netdev, data, ETH_FLAG_TXVLAN);
233 }
234
235 #ifdef CONFIG_NET_POLL_CONTROLLER
236 static void br_poll_controller(struct net_device *br_dev)
237 {
238 }
239
240 static void br_netpoll_cleanup(struct net_device *dev)
241 {
242         struct net_bridge *br = netdev_priv(dev);
243         struct net_bridge_port *p, *n;
244
245         list_for_each_entry_safe(p, n, &br->port_list, list) {
246                 br_netpoll_disable(p);
247         }
248 }
249
250 static int br_netpoll_setup(struct net_device *dev, struct netpoll_info *ni)
251 {
252         struct net_bridge *br = netdev_priv(dev);
253         struct net_bridge_port *p, *n;
254         int err = 0;
255
256         list_for_each_entry_safe(p, n, &br->port_list, list) {
257                 if (!p->dev)
258                         continue;
259
260                 err = br_netpoll_enable(p);
261                 if (err)
262                         goto fail;
263         }
264
265 out:
266         return err;
267
268 fail:
269         br_netpoll_cleanup(dev);
270         goto out;
271 }
272
273 int br_netpoll_enable(struct net_bridge_port *p)
274 {
275         struct netpoll *np;
276         int err = 0;
277
278         np = kzalloc(sizeof(*p->np), GFP_KERNEL);
279         err = -ENOMEM;
280         if (!np)
281                 goto out;
282
283         np->dev = p->dev;
284
285         err = __netpoll_setup(np);
286         if (err) {
287                 kfree(np);
288                 goto out;
289         }
290
291         p->np = np;
292
293 out:
294         return err;
295 }
296
297 void br_netpoll_disable(struct net_bridge_port *p)
298 {
299         struct netpoll *np = p->np;
300
301         if (!np)
302                 return;
303
304         p->np = NULL;
305
306         /* Wait for transmitting packets to finish before freeing. */
307         synchronize_rcu_bh();
308
309         __netpoll_cleanup(np);
310         kfree(np);
311 }
312
313 #endif
314
315 static int br_add_slave(struct net_device *dev, struct net_device *slave_dev)
316
317 {
318         struct net_bridge *br = netdev_priv(dev);
319
320         return br_add_if(br, slave_dev);
321 }
322
323 static int br_del_slave(struct net_device *dev, struct net_device *slave_dev)
324 {
325         struct net_bridge *br = netdev_priv(dev);
326
327         return br_del_if(br, slave_dev);
328 }
329
330 static const struct ethtool_ops br_ethtool_ops = {
331         .get_drvinfo    = br_getinfo,
332         .get_link       = ethtool_op_get_link,
333         .get_tx_csum    = ethtool_op_get_tx_csum,
334         .set_tx_csum    = br_set_tx_csum,
335         .get_sg         = ethtool_op_get_sg,
336         .set_sg         = br_set_sg,
337         .get_tso        = ethtool_op_get_tso,
338         .set_tso        = br_set_tso,
339         .get_ufo        = ethtool_op_get_ufo,
340         .set_ufo        = ethtool_op_set_ufo,
341         .get_flags      = ethtool_op_get_flags,
342         .set_flags      = br_set_flags,
343 };
344
345 static const struct net_device_ops br_netdev_ops = {
346         .ndo_open                = br_dev_open,
347         .ndo_stop                = br_dev_stop,
348         .ndo_init                = br_dev_init,
349         .ndo_start_xmit          = br_dev_xmit,
350         .ndo_get_stats64         = br_get_stats64,
351         .ndo_set_mac_address     = br_set_mac_address,
352         .ndo_set_multicast_list  = br_dev_set_multicast_list,
353         .ndo_change_mtu          = br_change_mtu,
354         .ndo_do_ioctl            = br_dev_ioctl,
355 #ifdef CONFIG_NET_POLL_CONTROLLER
356         .ndo_netpoll_setup       = br_netpoll_setup,
357         .ndo_netpoll_cleanup     = br_netpoll_cleanup,
358         .ndo_poll_controller     = br_poll_controller,
359 #endif
360         .ndo_add_slave           = br_add_slave,
361         .ndo_del_slave           = br_del_slave,
362 };
363
364 static void br_dev_free(struct net_device *dev)
365 {
366         struct net_bridge *br = netdev_priv(dev);
367
368         free_percpu(br->stats);
369         free_netdev(dev);
370 }
371
372 static struct device_type br_type = {
373         .name   = "bridge",
374 };
375
376 void br_dev_setup(struct net_device *dev)
377 {
378         struct net_bridge *br = netdev_priv(dev);
379
380         random_ether_addr(dev->dev_addr);
381         ether_setup(dev);
382
383         dev->netdev_ops = &br_netdev_ops;
384         dev->destructor = br_dev_free;
385         SET_ETHTOOL_OPS(dev, &br_ethtool_ops);
386         SET_NETDEV_DEVTYPE(dev, &br_type);
387         dev->tx_queue_len = 0;
388         dev->priv_flags = IFF_EBRIDGE;
389
390         dev->features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA |
391                         NETIF_F_GSO_MASK | NETIF_F_NO_CSUM | NETIF_F_LLTX |
392                         NETIF_F_NETNS_LOCAL | NETIF_F_GSO | NETIF_F_HW_VLAN_TX;
393
394         br->dev = dev;
395         spin_lock_init(&br->lock);
396         INIT_LIST_HEAD(&br->port_list);
397         spin_lock_init(&br->hash_lock);
398
399         br->bridge_id.prio[0] = 0x80;
400         br->bridge_id.prio[1] = 0x00;
401
402         memcpy(br->group_addr, br_group_address, ETH_ALEN);
403
404         br->feature_mask = dev->features;
405         br->stp_enabled = BR_NO_STP;
406         br->designated_root = br->bridge_id;
407         br->bridge_max_age = br->max_age = 20 * HZ;
408         br->bridge_hello_time = br->hello_time = 2 * HZ;
409         br->bridge_forward_delay = br->forward_delay = 15 * HZ;
410         br->ageing_time = 300 * HZ;
411
412         br_netfilter_rtable_init(br);
413         br_stp_timer_init(br);
414         br_multicast_init(br);
415 }