WorkStruct: make allyesconfig
[linux-3.10.git] / net / bridge / br_if.c
1 /*
2  *      Userspace interface
3  *      Linux ethernet bridge
4  *
5  *      Authors:
6  *      Lennert Buytenhek               <buytenh@gnu.org>
7  *
8  *      $Id: br_if.c,v 1.7 2001/12/24 00:59:55 davem Exp $
9  *
10  *      This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15
16 #include <linux/kernel.h>
17 #include <linux/netdevice.h>
18 #include <linux/ethtool.h>
19 #include <linux/if_arp.h>
20 #include <linux/module.h>
21 #include <linux/init.h>
22 #include <linux/rtnetlink.h>
23 #include <linux/if_ether.h>
24 #include <net/sock.h>
25
26 #include "br_private.h"
27
28 /*
29  * Determine initial path cost based on speed.
30  * using recommendations from 802.1d standard
31  *
32  * Need to simulate user ioctl because not all device's that support
33  * ethtool, use ethtool_ops.  Also, since driver might sleep need to
34  * not be holding any locks.
35  */
36 static int port_cost(struct net_device *dev)
37 {
38         struct ethtool_cmd ecmd = { ETHTOOL_GSET };
39         struct ifreq ifr;
40         mm_segment_t old_fs;
41         int err;
42
43         strncpy(ifr.ifr_name, dev->name, IFNAMSIZ);
44         ifr.ifr_data = (void __user *) &ecmd;
45
46         old_fs = get_fs();
47         set_fs(KERNEL_DS);
48         err = dev_ethtool(&ifr);
49         set_fs(old_fs);
50         
51         if (!err) {
52                 switch(ecmd.speed) {
53                 case SPEED_100:
54                         return 19;
55                 case SPEED_1000:
56                         return 4;
57                 case SPEED_10000:
58                         return 2;
59                 case SPEED_10:
60                         return 100;
61                 }
62         }
63
64         /* Old silly heuristics based on name */
65         if (!strncmp(dev->name, "lec", 3))
66                 return 7;
67
68         if (!strncmp(dev->name, "plip", 4))
69                 return 2500;
70
71         return 100;     /* assume old 10Mbps */
72 }
73
74
75 /*
76  * Check for port carrier transistions.
77  * Called from work queue to allow for calling functions that
78  * might sleep (such as speed check), and to debounce.
79  */
80 static void port_carrier_check(struct work_struct *work)
81 {
82         struct net_bridge_port *p;
83         struct net_device *dev;
84         struct net_bridge *br;
85
86         dev = container_of(work, struct net_bridge_port,
87                            carrier_check.work)->dev;
88         work_release(work);
89
90         rtnl_lock();
91         p = dev->br_port;
92         if (!p)
93                 goto done;
94         br = p->br;
95
96         if (netif_carrier_ok(dev))
97                 p->path_cost = port_cost(dev);
98
99         if (br->dev->flags & IFF_UP) {
100                 spin_lock_bh(&br->lock);
101                 if (netif_carrier_ok(dev)) {
102                         if (p->state == BR_STATE_DISABLED)
103                                 br_stp_enable_port(p);
104                 } else {
105                         if (p->state != BR_STATE_DISABLED)
106                                 br_stp_disable_port(p);
107                 }
108                 spin_unlock_bh(&br->lock);
109         }
110 done:
111         rtnl_unlock();
112 }
113
114 static void release_nbp(struct kobject *kobj)
115 {
116         struct net_bridge_port *p
117                 = container_of(kobj, struct net_bridge_port, kobj);
118         kfree(p);
119 }
120
121 static struct kobj_type brport_ktype = {
122 #ifdef CONFIG_SYSFS
123         .sysfs_ops = &brport_sysfs_ops,
124 #endif
125         .release = release_nbp,
126 };
127
128 static void destroy_nbp(struct net_bridge_port *p)
129 {
130         struct net_device *dev = p->dev;
131
132         p->br = NULL;
133         p->dev = NULL;
134         dev_put(dev);
135
136         kobject_put(&p->kobj);
137 }
138
139 static void destroy_nbp_rcu(struct rcu_head *head)
140 {
141         struct net_bridge_port *p =
142                         container_of(head, struct net_bridge_port, rcu);
143         destroy_nbp(p);
144 }
145
146 /* Delete port(interface) from bridge is done in two steps.
147  * via RCU. First step, marks device as down. That deletes
148  * all the timers and stops new packets from flowing through.
149  *
150  * Final cleanup doesn't occur until after all CPU's finished
151  * processing packets.
152  *
153  * Protected from multiple admin operations by RTNL mutex
154  */
155 static void del_nbp(struct net_bridge_port *p)
156 {
157         struct net_bridge *br = p->br;
158         struct net_device *dev = p->dev;
159
160         sysfs_remove_link(&br->ifobj, dev->name);
161
162         dev_set_promiscuity(dev, -1);
163
164         cancel_delayed_work(&p->carrier_check);
165
166         spin_lock_bh(&br->lock);
167         br_stp_disable_port(p);
168         spin_unlock_bh(&br->lock);
169
170         br_fdb_delete_by_port(br, p, 1);
171
172         list_del_rcu(&p->list);
173
174         rcu_assign_pointer(dev->br_port, NULL);
175
176         kobject_uevent(&p->kobj, KOBJ_REMOVE);
177         kobject_del(&p->kobj);
178
179         call_rcu(&p->rcu, destroy_nbp_rcu);
180 }
181
182 /* called with RTNL */
183 static void del_br(struct net_bridge *br)
184 {
185         struct net_bridge_port *p, *n;
186
187         list_for_each_entry_safe(p, n, &br->port_list, list) {
188                 del_nbp(p);
189         }
190
191         del_timer_sync(&br->gc_timer);
192
193         br_sysfs_delbr(br->dev);
194         unregister_netdevice(br->dev);
195 }
196
197 static struct net_device *new_bridge_dev(const char *name)
198 {
199         struct net_bridge *br;
200         struct net_device *dev;
201
202         dev = alloc_netdev(sizeof(struct net_bridge), name,
203                            br_dev_setup);
204         
205         if (!dev)
206                 return NULL;
207
208         br = netdev_priv(dev);
209         br->dev = dev;
210
211         spin_lock_init(&br->lock);
212         INIT_LIST_HEAD(&br->port_list);
213         spin_lock_init(&br->hash_lock);
214
215         br->bridge_id.prio[0] = 0x80;
216         br->bridge_id.prio[1] = 0x00;
217
218         memcpy(br->group_addr, br_group_address, ETH_ALEN);
219
220         br->feature_mask = dev->features;
221         br->stp_enabled = 0;
222         br->designated_root = br->bridge_id;
223         br->root_path_cost = 0;
224         br->root_port = 0;
225         br->bridge_max_age = br->max_age = 20 * HZ;
226         br->bridge_hello_time = br->hello_time = 2 * HZ;
227         br->bridge_forward_delay = br->forward_delay = 15 * HZ;
228         br->topology_change = 0;
229         br->topology_change_detected = 0;
230         br->ageing_time = 300 * HZ;
231         INIT_LIST_HEAD(&br->age_list);
232
233         br_stp_timer_init(br);
234
235         return dev;
236 }
237
238 /* find an available port number */
239 static int find_portno(struct net_bridge *br)
240 {
241         int index;
242         struct net_bridge_port *p;
243         unsigned long *inuse;
244
245         inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
246                         GFP_KERNEL);
247         if (!inuse)
248                 return -ENOMEM;
249
250         set_bit(0, inuse);      /* zero is reserved */
251         list_for_each_entry(p, &br->port_list, list) {
252                 set_bit(p->port_no, inuse);
253         }
254         index = find_first_zero_bit(inuse, BR_MAX_PORTS);
255         kfree(inuse);
256
257         return (index >= BR_MAX_PORTS) ? -EXFULL : index;
258 }
259
260 /* called with RTNL but without bridge lock */
261 static struct net_bridge_port *new_nbp(struct net_bridge *br, 
262                                        struct net_device *dev)
263 {
264         int index;
265         struct net_bridge_port *p;
266         
267         index = find_portno(br);
268         if (index < 0)
269                 return ERR_PTR(index);
270
271         p = kzalloc(sizeof(*p), GFP_KERNEL);
272         if (p == NULL)
273                 return ERR_PTR(-ENOMEM);
274
275         p->br = br;
276         dev_hold(dev);
277         p->dev = dev;
278         p->path_cost = port_cost(dev);
279         p->priority = 0x8000 >> BR_PORT_BITS;
280         p->port_no = index;
281         br_init_port(p);
282         p->state = BR_STATE_DISABLED;
283         INIT_DELAYED_WORK_NAR(&p->carrier_check, port_carrier_check);
284         br_stp_port_timer_init(p);
285
286         kobject_init(&p->kobj);
287         kobject_set_name(&p->kobj, SYSFS_BRIDGE_PORT_ATTR);
288         p->kobj.ktype = &brport_ktype;
289         p->kobj.parent = &(dev->class_dev.kobj);
290         p->kobj.kset = NULL;
291
292         return p;
293 }
294
295 int br_add_bridge(const char *name)
296 {
297         struct net_device *dev;
298         int ret;
299
300         dev = new_bridge_dev(name);
301         if (!dev) 
302                 return -ENOMEM;
303
304         rtnl_lock();
305         if (strchr(dev->name, '%')) {
306                 ret = dev_alloc_name(dev, dev->name);
307                 if (ret < 0) {
308                         free_netdev(dev);
309                         goto out;
310                 }
311         }
312
313         ret = register_netdevice(dev);
314         if (ret)
315                 goto out;
316
317         ret = br_sysfs_addbr(dev);
318         if (ret)
319                 unregister_netdevice(dev);
320  out:
321         rtnl_unlock();
322         return ret;
323 }
324
325 int br_del_bridge(const char *name)
326 {
327         struct net_device *dev;
328         int ret = 0;
329
330         rtnl_lock();
331         dev = __dev_get_by_name(name);
332         if (dev == NULL) 
333                 ret =  -ENXIO;  /* Could not find device */
334
335         else if (!(dev->priv_flags & IFF_EBRIDGE)) {
336                 /* Attempt to delete non bridge device! */
337                 ret = -EPERM;
338         }
339
340         else if (dev->flags & IFF_UP) {
341                 /* Not shutdown yet. */
342                 ret = -EBUSY;
343         } 
344
345         else 
346                 del_br(netdev_priv(dev));
347
348         rtnl_unlock();
349         return ret;
350 }
351
352 /* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
353 int br_min_mtu(const struct net_bridge *br)
354 {
355         const struct net_bridge_port *p;
356         int mtu = 0;
357
358         ASSERT_RTNL();
359
360         if (list_empty(&br->port_list))
361                 mtu = ETH_DATA_LEN;
362         else {
363                 list_for_each_entry(p, &br->port_list, list) {
364                         if (!mtu  || p->dev->mtu < mtu)
365                                 mtu = p->dev->mtu;
366                 }
367         }
368         return mtu;
369 }
370
371 /*
372  * Recomputes features using slave's features
373  */
374 void br_features_recompute(struct net_bridge *br)
375 {
376         struct net_bridge_port *p;
377         unsigned long features, checksum;
378
379         checksum = br->feature_mask & NETIF_F_ALL_CSUM ? NETIF_F_NO_CSUM : 0;
380         features = br->feature_mask & ~NETIF_F_ALL_CSUM;
381
382         list_for_each_entry(p, &br->port_list, list) {
383                 unsigned long feature = p->dev->features;
384
385                 if (checksum & NETIF_F_NO_CSUM && !(feature & NETIF_F_NO_CSUM))
386                         checksum ^= NETIF_F_NO_CSUM | NETIF_F_HW_CSUM;
387                 if (checksum & NETIF_F_HW_CSUM && !(feature & NETIF_F_HW_CSUM))
388                         checksum ^= NETIF_F_HW_CSUM | NETIF_F_IP_CSUM;
389                 if (!(feature & NETIF_F_IP_CSUM))
390                         checksum = 0;
391
392                 if (feature & NETIF_F_GSO)
393                         feature |= NETIF_F_GSO_SOFTWARE;
394                 feature |= NETIF_F_GSO;
395
396                 features &= feature;
397         }
398
399         if (!(checksum & NETIF_F_ALL_CSUM))
400                 features &= ~NETIF_F_SG;
401         if (!(features & NETIF_F_SG))
402                 features &= ~NETIF_F_GSO_MASK;
403
404         br->dev->features = features | checksum | NETIF_F_LLTX |
405                             NETIF_F_GSO_ROBUST;
406 }
407
408 /* called with RTNL */
409 int br_add_if(struct net_bridge *br, struct net_device *dev)
410 {
411         struct net_bridge_port *p;
412         int err = 0;
413
414         if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER)
415                 return -EINVAL;
416
417         if (dev->hard_start_xmit == br_dev_xmit)
418                 return -ELOOP;
419
420         if (dev->br_port != NULL)
421                 return -EBUSY;
422
423         p = new_nbp(br, dev);
424         if (IS_ERR(p))
425                 return PTR_ERR(p);
426
427         err = kobject_add(&p->kobj);
428         if (err)
429                 goto err0;
430
431         err = br_fdb_insert(br, p, dev->dev_addr);
432         if (err)
433                 goto err1;
434
435         err = br_sysfs_addif(p);
436         if (err)
437                 goto err2;
438
439         rcu_assign_pointer(dev->br_port, p);
440         dev_set_promiscuity(dev, 1);
441
442         list_add_rcu(&p->list, &br->port_list);
443
444         spin_lock_bh(&br->lock);
445         br_stp_recalculate_bridge_id(br);
446         br_features_recompute(br);
447         schedule_delayed_work(&p->carrier_check, BR_PORT_DEBOUNCE);
448         spin_unlock_bh(&br->lock);
449
450         dev_set_mtu(br->dev, br_min_mtu(br));
451         kobject_uevent(&p->kobj, KOBJ_ADD);
452
453         return 0;
454 err2:
455         br_fdb_delete_by_port(br, p, 1);
456 err1:
457         kobject_del(&p->kobj);
458 err0:
459         kobject_put(&p->kobj);
460         return err;
461 }
462
463 /* called with RTNL */
464 int br_del_if(struct net_bridge *br, struct net_device *dev)
465 {
466         struct net_bridge_port *p = dev->br_port;
467         
468         if (!p || p->br != br) 
469                 return -EINVAL;
470
471         del_nbp(p);
472
473         spin_lock_bh(&br->lock);
474         br_stp_recalculate_bridge_id(br);
475         br_features_recompute(br);
476         spin_unlock_bh(&br->lock);
477
478         return 0;
479 }
480
481 void __exit br_cleanup_bridges(void)
482 {
483         struct net_device *dev, *nxt;
484
485         rtnl_lock();
486         for (dev = dev_base; dev; dev = nxt) {
487                 nxt = dev->next;
488                 if (dev->priv_flags & IFF_EBRIDGE)
489                         del_br(dev->priv);
490         }
491         rtnl_unlock();
492
493 }