release/src-rt/linux/linux-2.6/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 #ifdef HNDCTF
  29 #include <ctf/hndctf.h>
  30 extern ctf_t *kcih;
  31 #endif /* HNDCTF */
  32
  33 /*
  34  * Determine initial path cost based on speed.
  35  * using recommendations from 802.1d standard
  36  *
  37  * Need to simulate user ioctl because not all device's that support
  38  * ethtool, use ethtool_ops.  Also, since driver might sleep need to
  39  * not be holding any locks.
  40  */
  41 static int port_cost(struct net_device *dev)
  42 {
  43         struct ethtool_cmd ecmd = { ETHTOOL_GSET };
  44         struct ifreq ifr;
  45         mm_segment_t old_fs;
  46         int err;
  47
  48         strncpy(ifr.ifr_name, dev->name, IFNAMSIZ);
  49         ifr.ifr_data = (void __user *) &ecmd;
  50
  51         old_fs = get_fs();
  52         set_fs(KERNEL_DS);
  53         err = dev_ethtool(&ifr);
  54         set_fs(old_fs);
  55
  56         if (!err) {
  57                 switch(ecmd.speed) {
  58                 case SPEED_100:
  59                         return 19;
  60                 case SPEED_1000:
  61                         return 4;
  62                 case SPEED_10000:
  63                         return 2;
  64                 case SPEED_10:
  65                         return 100;
  66                 }
  67         }
  68
  69         /* Old silly heuristics based on name */
  70         if (!strncmp(dev->name, "lec", 3))
  71                 return 7;
  72
  73         if (!strncmp(dev->name, "plip", 4))
  74                 return 2500;
  75
  76         return 100;     /* assume old 10Mbps */
  77 }
  78
  79
  80 /*
  81  * Check for port carrier transistions.
  82  * Called from work queue to allow for calling functions that
  83  * might sleep (such as speed check), and to debounce.
  84  */
  85 void br_port_carrier_check(struct net_bridge_port *p)
  86 {
  87         struct net_device *dev = p->dev;
  88         struct net_bridge *br = p->br;
  89
  90         if (netif_carrier_ok(dev))
  91                 p->path_cost = port_cost(dev);
  92
  93         if (netif_running(br->dev)) {
  94                 spin_lock_bh(&br->lock);
  95                 if (netif_carrier_ok(dev)) {
  96                         if (p->state == BR_STATE_DISABLED)
  97                                 br_stp_enable_port(p);
  98                 } else {
  99                         if (p->state != BR_STATE_DISABLED)
 100                                 br_stp_disable_port(p);
 101                 }
 102                 spin_unlock_bh(&br->lock);
 103         }
 104 }
 105
 106 static void release_nbp(struct kobject *kobj)
 107 {
 108         struct net_bridge_port *p
 109                 = container_of(kobj, struct net_bridge_port, kobj);
 110         kfree(p);
 111 }
 112
 113 static struct kobj_type brport_ktype = {
 114 #ifdef CONFIG_SYSFS
 115         .sysfs_ops = &brport_sysfs_ops,
 116 #endif
 117         .release = release_nbp,
 118 };
 119
 120 static void destroy_nbp(struct net_bridge_port *p)
 121 {
 122         struct net_device *dev = p->dev;
 123
 124         p->br = NULL;
 125         p->dev = NULL;
 126         dev_put(dev);
 127
 128         kobject_put(&p->kobj);
 129 }
 130
 131 static void destroy_nbp_rcu(struct rcu_head *head)
 132 {
 133         struct net_bridge_port *p =
 134                         container_of(head, struct net_bridge_port, rcu);
 135         destroy_nbp(p);
 136 }
 137
 138 /* Delete port(interface) from bridge is done in two steps.
 139  * via RCU. First step, marks device as down. That deletes
 140  * all the timers and stops new packets from flowing through.
 141  *
 142  * Final cleanup doesn't occur until after all CPU's finished
 143  * processing packets.
 144  *
 145  * Protected from multiple admin operations by RTNL mutex
 146  */
 147 static void del_nbp(struct net_bridge_port *p)
 148 {
 149         struct net_bridge *br = p->br;
 150         struct net_device *dev = p->dev;
 151
 152         sysfs_remove_link(&br->ifobj, dev->name);
 153
 154         dev_set_promiscuity(dev, -1);
 155
 156         spin_lock_bh(&br->lock);
 157         br_stp_disable_port(p);
 158         spin_unlock_bh(&br->lock);
 159
 160         br_ifinfo_notify(RTM_DELLINK, p);
 161
 162         br_fdb_delete_by_port(br, p, 1);
 163
 164         list_del_rcu(&p->list);
 165
 166         rcu_assign_pointer(dev->br_port, NULL);
 167
 168         kobject_uevent(&p->kobj, KOBJ_REMOVE);
 169         kobject_del(&p->kobj);
 170
 171         call_rcu(&p->rcu, destroy_nbp_rcu);
 172 }
 173
 174 /* called with RTNL */
 175 static void del_br(struct net_bridge *br)
 176 {
 177         struct net_bridge_port *p, *n;
 178
 179         list_for_each_entry_safe(p, n, &br->port_list, list) {
 180                 del_nbp(p);
 181         }
 182
 183         del_timer_sync(&br->gc_timer);
 184
 185         br_sysfs_delbr(br->dev);
 186         unregister_netdevice(br->dev);
 187 }
 188
 189 static struct net_device *new_bridge_dev(const char *name)
 190 {
 191         struct net_bridge *br;
 192         struct net_device *dev;
 193
 194         dev = alloc_netdev(sizeof(struct net_bridge), name,
 195                            br_dev_setup);
 196
 197         if (!dev)
 198                 return NULL;
 199
 200         br = netdev_priv(dev);
 201         br->dev = dev;
 202
 203         spin_lock_init(&br->lock);
 204         INIT_LIST_HEAD(&br->port_list);
 205         spin_lock_init(&br->hash_lock);
 206
 207         br->bridge_id.prio[0] = 0x80;
 208         br->bridge_id.prio[1] = 0x00;
 209
 210         memcpy(br->group_addr, br_group_address, ETH_ALEN);
 211
 212         br->feature_mask = dev->features;
 213         br->stp_enabled = BR_NO_STP;
 214         br->designated_root = br->bridge_id;
 215         br->root_path_cost = 0;
 216         br->root_port = 0;
 217         br->bridge_max_age = br->max_age = 20 * HZ;
 218         br->bridge_hello_time = br->hello_time = 2 * HZ;
 219         br->bridge_forward_delay = br->forward_delay = 15 * HZ;
 220         br->topology_change = 0;
 221         br->topology_change_detected = 0;
 222         br->ageing_time = 300 * HZ;
 223         INIT_LIST_HEAD(&br->age_list);
 224
 225         br_stp_timer_init(br);
 226
 227         return dev;
 228 }
 229
 230 /* find an available port number */
 231 static int find_portno(struct net_bridge *br)
 232 {
 233         int index;
 234         struct net_bridge_port *p;
 235         unsigned long *inuse;
 236
 237         inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
 238                         GFP_KERNEL);
 239         if (!inuse)
 240                 return -ENOMEM;
 241
 242         set_bit(0, inuse);      /* zero is reserved */
 243         list_for_each_entry(p, &br->port_list, list) {
 244                 set_bit(p->port_no, inuse);
 245         }
 246         index = find_first_zero_bit(inuse, BR_MAX_PORTS);
 247         kfree(inuse);
 248
 249         return (index >= BR_MAX_PORTS) ? -EXFULL : index;
 250 }
 251
 252 /* called with RTNL but without bridge lock */
 253 static struct net_bridge_port *new_nbp(struct net_bridge *br,
 254                                        struct net_device *dev)
 255 {
 256         int index;
 257         struct net_bridge_port *p;
 258
 259         index = find_portno(br);
 260         if (index < 0)
 261                 return ERR_PTR(index);
 262
 263         p = kzalloc(sizeof(*p), GFP_KERNEL);
 264         if (p == NULL)
 265                 return ERR_PTR(-ENOMEM);
 266
 267         p->br = br;
 268         dev_hold(dev);
 269         p->dev = dev;
 270         p->path_cost = port_cost(dev);
 271         p->priority = 0x8000 >> BR_PORT_BITS;
 272         p->port_no = index;
 273         br_init_port(p);
 274         p->state = BR_STATE_DISABLED;
 275         br_stp_port_timer_init(p);
 276
 277         kobject_init(&p->kobj);
 278         kobject_set_name(&p->kobj, SYSFS_BRIDGE_PORT_ATTR);
 279         p->kobj.ktype = &brport_ktype;
 280         p->kobj.parent = &(dev->dev.kobj);
 281         p->kobj.kset = NULL;
 282
 283         return p;
 284 }
 285
 286 int br_add_bridge(const char *name)
 287 {
 288         struct net_device *dev;
 289         int ret;
 290
 291         dev = new_bridge_dev(name);
 292         if (!dev)
 293                 return -ENOMEM;
 294
 295         rtnl_lock();
 296         if (strchr(dev->name, '%')) {
 297                 ret = dev_alloc_name(dev, dev->name);
 298                 if (ret < 0) {
 299                         free_netdev(dev);
 300                         goto out;
 301                 }
 302         }
 303
 304         ret = register_netdevice(dev);
 305         if (ret)
 306                 goto out;
 307
 308 #ifdef HNDCTF
 309         if ((ctf_dev_register(kcih, dev, TRUE) != BCME_OK) ||
 310             (ctf_enable(kcih, dev, TRUE) != BCME_OK)) {
 311                 ctf_dev_unregister(kcih, dev);
 312                 unregister_netdevice(dev);
 313                 ret = -ENXIO;
 314                 goto out;
 315         }
 316 #endif /* HNDCTF */
 317
 318         ret = br_sysfs_addbr(dev);
 319         if (ret)
 320                 unregister_netdevice(dev);
 321  out:
 322         rtnl_unlock();
 323         return ret;
 324 }
 325
 326 int br_del_bridge(const char *name)
 327 {
 328         struct net_device *dev;
 329         int ret = 0;
 330
 331         rtnl_lock();
 332         dev = __dev_get_by_name(name);
 333         if (dev == NULL)
 334                 ret =  -ENXIO;  /* Could not find device */
 335
 336         else if (!(dev->priv_flags & IFF_EBRIDGE)) {
 337                 /* Attempt to delete non bridge device! */
 338                 ret = -EPERM;
 339         }
 340
 341         else if (dev->flags & IFF_UP) {
 342                 /* Not shutdown yet. */
 343                 ret = -EBUSY;
 344         }
 345
 346         else {
 347 #ifdef HNDCTF
 348                 ctf_dev_unregister(kcih, dev);
 349 #endif /* HNDCTF */
 350                 del_br(netdev_priv(dev));
 351         }
 352
 353         rtnl_unlock();
 354         return ret;
 355 }
 356
 357 /* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */
 358 int br_min_mtu(const struct net_bridge *br)
 359 {
 360         const struct net_bridge_port *p;
 361         int mtu = 0;
 362
 363         ASSERT_RTNL();
 364
 365         if (list_empty(&br->port_list))
 366                 mtu = ETH_DATA_LEN;
 367         else {
 368                 list_for_each_entry(p, &br->port_list, list) {
 369                         if (!mtu  || p->dev->mtu < mtu)
 370                                 mtu = p->dev->mtu;
 371                 }
 372         }
 373         return mtu;
 374 }
 375
 376 /*
 377  * Recomputes features using slave's features
 378  */
 379 void br_features_recompute(struct net_bridge *br)
 380 {
 381         struct net_bridge_port *p;
 382         unsigned long features;
 383
 384         features = br->feature_mask;
 385
 386         list_for_each_entry(p, &br->port_list, list) {
 387                 features = netdev_compute_features(features, p->dev->features);
 388         }
 389
 390         br->dev->features = features;
 391 }
 392
 393 /* called with RTNL */
 394 int br_add_if(struct net_bridge *br, struct net_device *dev)
 395 {
 396         struct net_bridge_port *p;
 397         int err = 0;
 398
 399         if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER)
 400                 return -EINVAL;
 401
 402         if (dev->hard_start_xmit == br_dev_xmit)
 403                 return -ELOOP;
 404
 405         if (dev->br_port != NULL)
 406                 return -EBUSY;
 407
 408         p = new_nbp(br, dev);
 409         if (IS_ERR(p))
 410                 return PTR_ERR(p);
 411
 412         err = kobject_add(&p->kobj);
 413         if (err)
 414                 goto err0;
 415
 416         err = br_fdb_insert(br, p, dev->dev_addr);
 417         if (err)
 418                 goto err1;
 419
 420         err = br_sysfs_addif(p);
 421         if (err)
 422                 goto err2;
 423
 424         rcu_assign_pointer(dev->br_port, p);
 425         dev_set_promiscuity(dev, 1);
 426
 427         list_add_rcu(&p->list, &br->port_list);
 428
 429         spin_lock_bh(&br->lock);
 430         br_stp_recalculate_bridge_id(br);
 431         br_features_recompute(br);
 432
 433         if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) &&
 434             (br->dev->flags & IFF_UP))
 435                 br_stp_enable_port(p);
 436         spin_unlock_bh(&br->lock);
 437
 438         br_ifinfo_notify(RTM_NEWLINK, p);
 439
 440         dev_set_mtu(br->dev, br_min_mtu(br));
 441
 442         kobject_uevent(&p->kobj, KOBJ_ADD);
 443
 444         return 0;
 445 err2:
 446         br_fdb_delete_by_port(br, p, 1);
 447 err1:
 448         kobject_del(&p->kobj);
 449 err0:
 450         kobject_put(&p->kobj);
 451         return err;
 452 }
 453
 454 /* called with RTNL */
 455 int br_del_if(struct net_bridge *br, struct net_device *dev)
 456 {
 457         struct net_bridge_port *p = dev->br_port;
 458
 459         if (!p || p->br != br)
 460                 return -EINVAL;
 461
 462         del_nbp(p);
 463
 464         spin_lock_bh(&br->lock);
 465         br_stp_recalculate_bridge_id(br);
 466         br_features_recompute(br);
 467         spin_unlock_bh(&br->lock);
 468
 469         return 0;
 470 }
 471
 472 void __exit br_cleanup_bridges(void)
 473 {
 474         struct net_device *dev, *nxt;
 475
 476         rtnl_lock();
 477         for_each_netdev_safe(dev, nxt)
 478                 if (dev->priv_flags & IFF_EBRIDGE)
 479                         del_br(dev->priv);
 480         rtnl_unlock();
 481
 482 }