1/* 2 * Userspace interface 3 * Linux ethernet bridge 4 * 5 * Authors: 6 * Lennert Buytenhek <buytenh@gnu.org> 7 * 8 * $Id: br_if.c,v 1.4.2.1 2010/11/05 06:20:14 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#endif /* HNDCTF */ 31 32/* 33 * Determine initial path cost based on speed. 34 * using recommendations from 802.1d standard 35 * 36 * Need to simulate user ioctl because not all device's that support 37 * ethtool, use ethtool_ops. Also, since driver might sleep need to 38 * not be holding any locks. 39 */ 40static int port_cost(struct net_device *dev) 41{ 42 struct ethtool_cmd ecmd = { ETHTOOL_GSET }; 43 struct ifreq ifr; 44 mm_segment_t old_fs; 45 int err; 46 47 strncpy(ifr.ifr_name, dev->name, IFNAMSIZ); 48 ifr.ifr_data = (void __user *) &ecmd; 49 50 old_fs = get_fs(); 51 set_fs(KERNEL_DS); 52 err = dev_ethtool(&ifr); 53 set_fs(old_fs); 54 55 if (!err) { 56 switch(ecmd.speed) { 57 case SPEED_100: 58 return 19; 59 case SPEED_1000: 60 return 4; 61 case SPEED_10000: 62 return 2; 63 case SPEED_10: 64 return 100; 65 } 66 } 67 68 /* Old silly heuristics based on name */ 69 if (!strncmp(dev->name, "lec", 3)) 70 return 7; 71 72 if (!strncmp(dev->name, "plip", 4)) 73 return 2500; 74 75 return 100; /* assume old 10Mbps */ 76} 77 78 79/* 80 * Check for port carrier transistions. 81 * Called from work queue to allow for calling functions that 82 * might sleep (such as speed check), and to debounce. 83 */ 84void br_port_carrier_check(struct net_bridge_port *p) 85{ 86 struct net_device *dev = p->dev; 87 struct net_bridge *br = p->br; 88 89 if (netif_carrier_ok(dev)) 90 p->path_cost = port_cost(dev); 91 92 if (netif_running(br->dev)) { 93 spin_lock_bh(&br->lock); 94 if (netif_carrier_ok(dev)) { 95 if (p->state == BR_STATE_DISABLED) 96 br_stp_enable_port(p); 97 } else { 98 if (p->state != BR_STATE_DISABLED) 99 br_stp_disable_port(p); 100 } 101 spin_unlock_bh(&br->lock); 102 } 103} 104 105static void release_nbp(struct kobject *kobj) 106{ 107 struct net_bridge_port *p 108 = container_of(kobj, struct net_bridge_port, kobj); 109 kfree(p); 110} 111 112static struct kobj_type brport_ktype = { 113#ifdef CONFIG_SYSFS 114 .sysfs_ops = &brport_sysfs_ops, 115#endif 116 .release = release_nbp, 117}; 118 119static void destroy_nbp(struct net_bridge_port *p) 120{ 121 struct net_device *dev = p->dev; 122 123 p->br = NULL; 124 p->dev = NULL; 125 dev_put(dev); 126 127 kobject_put(&p->kobj); 128} 129 130static void destroy_nbp_rcu(struct rcu_head *head) 131{ 132 struct net_bridge_port *p = 133 container_of(head, struct net_bridge_port, rcu); 134 destroy_nbp(p); 135} 136 137/* Delete port(interface) from bridge is done in two steps. 138 * via RCU. First step, marks device as down. That deletes 139 * all the timers and stops new packets from flowing through. 140 * 141 * Final cleanup doesn't occur until after all CPU's finished 142 * processing packets. 143 * 144 * Protected from multiple admin operations by RTNL mutex 145 */ 146static void del_nbp(struct net_bridge_port *p) 147{ 148 struct net_bridge *br = p->br; 149 struct net_device *dev = p->dev; 150 151 sysfs_remove_link(&br->ifobj, dev->name); 152 153 dev_set_promiscuity(dev, -1); 154 155 spin_lock_bh(&br->lock); 156 br_stp_disable_port(p); 157 spin_unlock_bh(&br->lock); 158 159 br_ifinfo_notify(RTM_DELLINK, p); 160 161 br_fdb_delete_by_port(br, p, 1); 162 163 list_del_rcu(&p->list); 164 165 rcu_assign_pointer(dev->br_port, NULL); 166 167 kobject_uevent(&p->kobj, KOBJ_REMOVE); 168 kobject_del(&p->kobj); 169 170 call_rcu(&p->rcu, destroy_nbp_rcu); 171} 172 173/* called with RTNL */ 174static void del_br(struct net_bridge *br) 175{ 176 struct net_bridge_port *p, *n; 177 178 list_for_each_entry_safe(p, n, &br->port_list, list) { 179 del_nbp(p); 180 } 181 182 del_timer_sync(&br->gc_timer); 183 184 br_sysfs_delbr(br->dev); 185 unregister_netdevice(br->dev); 186} 187 188static struct net_device *new_bridge_dev(const char *name) 189{ 190 struct net_bridge *br; 191 struct net_device *dev; 192 193 dev = alloc_netdev(sizeof(struct net_bridge), name, 194 br_dev_setup); 195 196 if (!dev) 197 return NULL; 198 199 br = netdev_priv(dev); 200 br->dev = dev; 201 202 spin_lock_init(&br->lock); 203 INIT_LIST_HEAD(&br->port_list); 204 spin_lock_init(&br->hash_lock); 205 206 br->bridge_id.prio[0] = 0x80; 207 br->bridge_id.prio[1] = 0x00; 208 209 memcpy(br->group_addr, br_group_address, ETH_ALEN); 210 211 br->feature_mask = dev->features; 212 br->stp_enabled = BR_NO_STP; 213 br->designated_root = br->bridge_id; 214 br->root_path_cost = 0; 215 br->root_port = 0; 216 br->bridge_max_age = br->max_age = 20 * HZ; 217 br->bridge_hello_time = br->hello_time = 2 * HZ; 218 br->bridge_forward_delay = br->forward_delay = 15 * HZ; 219 br->topology_change = 0; 220 br->topology_change_detected = 0; 221 br->ageing_time = 300 * HZ; 222 INIT_LIST_HEAD(&br->age_list); 223 224#ifdef CONFIG_INET_GSO 225 br->feature_mask |= NETIF_F_GSO; 226#endif /* CONFIG_INET_GSO */ 227 br_stp_timer_init(br); 228 229 return dev; 230} 231 232/* find an available port number */ 233static int find_portno(struct net_bridge *br) 234{ 235 int index; 236 struct net_bridge_port *p; 237 unsigned long *inuse; 238 239 inuse = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long), 240 GFP_KERNEL); 241 if (!inuse) 242 return -ENOMEM; 243 244 set_bit(0, inuse); /* zero is reserved */ 245 list_for_each_entry(p, &br->port_list, list) { 246 set_bit(p->port_no, inuse); 247 } 248 index = find_first_zero_bit(inuse, BR_MAX_PORTS); 249 kfree(inuse); 250 251 return (index >= BR_MAX_PORTS) ? -EXFULL : index; 252} 253 254/* called with RTNL but without bridge lock */ 255static struct net_bridge_port *new_nbp(struct net_bridge *br, 256 struct net_device *dev) 257{ 258 int index; 259 struct net_bridge_port *p; 260 261 index = find_portno(br); 262 if (index < 0) 263 return ERR_PTR(index); 264 265 p = kzalloc(sizeof(*p), GFP_KERNEL); 266 if (p == NULL) 267 return ERR_PTR(-ENOMEM); 268 269 p->br = br; 270 dev_hold(dev); 271 p->dev = dev; 272 p->path_cost = port_cost(dev); 273 p->priority = 0x8000 >> BR_PORT_BITS; 274 p->port_no = index; 275 br_init_port(p); 276 p->state = BR_STATE_DISABLED; 277 br_stp_port_timer_init(p); 278 279 kobject_init(&p->kobj); 280 kobject_set_name(&p->kobj, SYSFS_BRIDGE_PORT_ATTR); 281 p->kobj.ktype = &brport_ktype; 282 p->kobj.parent = &(dev->dev.kobj); 283 p->kobj.kset = NULL; 284 285 return p; 286} 287 288int br_add_bridge(const char *name) 289{ 290 struct net_device *dev; 291 int ret; 292 293 dev = new_bridge_dev(name); 294 if (!dev) 295 return -ENOMEM; 296 297#ifdef CONFIG_INET_GSO 298 dev->features |= NETIF_F_GSO; 299#endif /* CONFIG_INET_GSO */ 300 301 rtnl_lock(); 302 if (strchr(dev->name, '%')) { 303 ret = dev_alloc_name(dev, dev->name); 304 if (ret < 0) { 305 free_netdev(dev); 306 goto out; 307 } 308 } 309 310 ret = register_netdevice(dev); 311 if (ret) 312 goto out; 313 314#ifdef HNDCTF 315 if ((ctf_dev_register(kcih, dev, TRUE) != BCME_OK) || 316 (ctf_enable(kcih, dev, TRUE) != BCME_OK)) { 317 ctf_dev_unregister(kcih, dev); 318 unregister_netdevice(dev); 319 ret = -ENXIO; 320 goto out; 321 } 322#endif /* HNDCTF */ 323 324 ret = br_sysfs_addbr(dev); 325 if (ret) 326 unregister_netdevice(dev); 327 out: 328 rtnl_unlock(); 329 return ret; 330} 331 332int br_del_bridge(const char *name) 333{ 334 struct net_device *dev; 335 int ret = 0; 336 337 rtnl_lock(); 338 dev = __dev_get_by_name(name); 339 if (dev == NULL) 340 ret = -ENXIO; /* Could not find device */ 341 342 else if (!(dev->priv_flags & IFF_EBRIDGE)) { 343 /* Attempt to delete non bridge device! */ 344 ret = -EPERM; 345 } 346 347 else if (dev->flags & IFF_UP) { 348 /* Not shutdown yet. */ 349 ret = -EBUSY; 350 } 351 352 else { 353#ifdef HNDCTF 354 ctf_dev_unregister(kcih, dev); 355#endif /* HNDCTF */ 356 del_br(netdev_priv(dev)); 357 } 358 359 rtnl_unlock(); 360 return ret; 361} 362 363/* MTU of the bridge pseudo-device: ETH_DATA_LEN or the minimum of the ports */ 364int br_min_mtu(const struct net_bridge *br) 365{ 366 const struct net_bridge_port *p; 367 int mtu = 0; 368 369 ASSERT_RTNL(); 370 371 if (list_empty(&br->port_list)) 372 mtu = ETH_DATA_LEN; 373 else { 374 list_for_each_entry(p, &br->port_list, list) { 375 if (!mtu || p->dev->mtu < mtu) 376 mtu = p->dev->mtu; 377 } 378 } 379 return mtu; 380} 381 382/* 383 * Recomputes features using slave's features 384 */ 385void br_features_recompute(struct net_bridge *br) 386{ 387 struct net_bridge_port *p; 388 unsigned long features, checksum; 389 390 checksum = br->feature_mask & NETIF_F_ALL_CSUM ? NETIF_F_NO_CSUM : 0; 391 features = br->feature_mask & ~NETIF_F_ALL_CSUM; 392 393 list_for_each_entry(p, &br->port_list, list) { 394 unsigned long feature = p->dev->features; 395 396 if (checksum & NETIF_F_NO_CSUM && !(feature & NETIF_F_NO_CSUM)) 397 checksum ^= NETIF_F_NO_CSUM | NETIF_F_HW_CSUM; 398 if (checksum & NETIF_F_HW_CSUM && !(feature & NETIF_F_HW_CSUM)) 399 checksum ^= NETIF_F_HW_CSUM | NETIF_F_IP_CSUM; 400 if (!(feature & NETIF_F_IP_CSUM)) 401 checksum = 0; 402 403 if (feature & NETIF_F_GSO) 404 feature |= NETIF_F_GSO_SOFTWARE; 405 feature |= NETIF_F_GSO; 406 407 features &= feature; 408 } 409 410 if (!(checksum & NETIF_F_ALL_CSUM)) 411 features &= ~NETIF_F_SG; 412 if (!(features & NETIF_F_SG)) 413 features &= ~NETIF_F_GSO_MASK; 414 415 br->dev->features = features | checksum | NETIF_F_LLTX | 416 NETIF_F_GSO_ROBUST; 417} 418 419/* called with RTNL */ 420int br_add_if(struct net_bridge *br, struct net_device *dev) 421{ 422 struct net_bridge_port *p; 423 int err = 0; 424 425 if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER) 426 return -EINVAL; 427 428 if (dev->hard_start_xmit == br_dev_xmit) 429 return -ELOOP; 430 431 if (dev->br_port != NULL) 432 return -EBUSY; 433 434 p = new_nbp(br, dev); 435 if (IS_ERR(p)) 436 return PTR_ERR(p); 437 438 err = kobject_add(&p->kobj); 439 if (err) 440 goto err0; 441 442 err = br_fdb_insert(br, p, dev->dev_addr); 443 if (err) 444 goto err1; 445 446 err = br_sysfs_addif(p); 447 if (err) 448 goto err2; 449 450 rcu_assign_pointer(dev->br_port, p); 451 dev_set_promiscuity(dev, 1); 452 453 list_add_rcu(&p->list, &br->port_list); 454 455 spin_lock_bh(&br->lock); 456 br_stp_recalculate_bridge_id(br); 457 br_features_recompute(br); 458 459 if ((dev->flags & IFF_UP) && netif_carrier_ok(dev) && 460 (br->dev->flags & IFF_UP)) 461 br_stp_enable_port(p); 462 spin_unlock_bh(&br->lock); 463 464 br_ifinfo_notify(RTM_NEWLINK, p); 465 466 dev_set_mtu(br->dev, br_min_mtu(br)); 467 468 kobject_uevent(&p->kobj, KOBJ_ADD); 469 470 return 0; 471err2: 472 br_fdb_delete_by_port(br, p, 1); 473err1: 474 kobject_del(&p->kobj); 475err0: 476 kobject_put(&p->kobj); 477 return err; 478} 479 480/* called with RTNL */ 481int br_del_if(struct net_bridge *br, struct net_device *dev) 482{ 483 struct net_bridge_port *p = dev->br_port; 484 485 if (!p || p->br != br) 486 return -EINVAL; 487 488 del_nbp(p); 489 490 spin_lock_bh(&br->lock); 491 br_stp_recalculate_bridge_id(br); 492 br_features_recompute(br); 493 spin_unlock_bh(&br->lock); 494 495 return 0; 496} 497 498void __exit br_cleanup_bridges(void) 499{ 500 struct net_device *dev, *nxt; 501 502 rtnl_lock(); 503 for_each_netdev_safe(dev, nxt) 504 if (dev->priv_flags & IFF_EBRIDGE) 505 del_br(dev->priv); 506 rtnl_unlock(); 507 508} 509