/* * Userspace interface * Linux ethernet bridge * * Authors: * Lennert Buytenhek <buytenh@gnu.org> * * $Id: br_if.c,v 1.7 2001/12/24 00:59:55 davem Exp $ * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ #include <linux/kernel.h> #include <linux/netdevice.h> #include <linux/ethtool.h> #include <linux/if_arp.h> #include <linux/module.h> #include <linux/init.h> #include <linux/rtnetlink.h> #include <net/sock.h> #include "br_private.h" /* * Determine initial path cost based on speed. * using recommendations from 802.1d standard * * Need to simulate user ioctl because not all device's that support * ethtool, use ethtool_ops. Also, since driver might sleep need to * not be holding any locks. */ static int br_initial_port_cost(struct net_device *dev) { struct ethtool_cmd ecmd = { ETHTOOL_GSET }; struct ifreq ifr; mm_segment_t old_fs; int err; strncpy(ifr.ifr_name, dev->name, IFNAMSIZ); ifr.ifr_data = (void __user *) &ecmd; old_fs = get_fs(); set_fs(KERNEL_DS); err = dev_ethtool(&ifr); set_fs(old_fs); if (!err) { switch(ecmd.speed) { case SPEED_100: return 19; case SPEED_1000: return 4; case SPEED_10000: return 2; case SPEED_10: return 100; default: pr_info("bridge: can't decode speed from %s: %d\n", dev->name, ecmd.speed); return 100; } } /* Old silly heuristics based on name */ if (!strncmp(dev->name, "lec", 3)) return 7; if (!strncmp(dev->name, "plip", 4)) return 2500; return 100; /* assume old 10Mbps */ } static void destroy_nbp(struct net_bridge_port *p) { struct net_device *dev = p->dev; p->br = NULL; p->dev = NULL; dev_put(dev); br_sysfs_freeif(p); } static void destroy_nbp_rcu(struct rcu_head *head) { struct net_bridge_port *p = container_of(head, struct net_bridge_port, rcu); destroy_nbp(p); } /* called with RTNL */ static void del_nbp(struct net_bridge_port *p) { struct net_bridge *br = p->br; struct net_device *dev = p->dev; dev->br_port = NULL; dev_set_promiscuity(dev, -1); spin_lock_bh(&br->lock); br_stp_disable_port(p); spin_unlock_bh(&br->lock); br_fdb_delete_by_port(br, p); list_del_rcu(&p->list); del_timer_sync(&p->message_age_timer); del_timer_sync(&p->forward_delay_timer); del_timer_sync(&p->hold_timer); call_rcu(&p->rcu, destroy_nbp_rcu); } /* called with RTNL */ static void del_br(struct net_bridge *br) { struct net_bridge_port *p, *n; list_for_each_entry_safe(p, n, &br->port_list, list) { br_sysfs_removeif(p); del_nbp(p); } del_timer_sync(&br->gc_timer); br_sysfs_delbr(br->dev); unregister_netdevice(br->dev); } static struct net_device *new_bridge_dev(const char *name) { struct net_bridge *br; struct net_device *dev; dev = alloc_netdev(sizeof(struct net_bridge), name, br_dev_setup); if (!dev) return NULL; br = netdev_priv(dev); br->dev = dev; spin_lock_init(&br->lock); INIT_LIST_HEAD(&br->port_list); spin_lock_init(&br->hash_lock); br->bridge_id.prio[0] = 0x80; br->bridge_id.prio[1] = 0x00; memset(br->bridge_id.addr, 0, ETH_ALEN); br->stp_enabled = 0; br->designated_root = br->bridge_id; br->root_path_cost = 0; br->root_port = 0; br->bridge_max_age = br->max_age = 20 * HZ; br->bridge_hello_time = br->hello_time = 2 * HZ; br->bridge_forward_delay = br->forward_delay = 15 * HZ; br->topology_change = 0; br->topology_change_detected = 0; br->ageing_time = 300 * HZ; INIT_LIST_HEAD(&br->age_list); br_stp_timer_init(br); return dev; } /* find an available port number */ static int find_portno(struct net_bridge *br) { int index; struct net_bridge_port *p; unsigned long *inuse; inuse = kmalloc(BITS_TO_LONGS(BR_MAX_PORTS)*sizeof(unsigned long), GFP_KERNEL); if (!inuse) return -ENOMEM; memset(inuse, 0, BITS_TO_LONGS(BR_MAX_PORTS)*sizeof(unsigned long)); set_bit(0, inuse); /* zero is reserved */ list_for_each_entry(p, &br->port_list, list) { set_bit(p->port_no, inuse); } index = find_first_zero_bit(inuse, BR_MAX_PORTS); kfree(inuse); return (index >= BR_MAX_PORTS) ? -EXFULL : index; } /* called with RTNL */ static struct net_bridge_port *new_nbp(struct net_bridge *br, struct net_device *dev, unsigned long cost) { int index; struct net_bridge_port *p; index = find_portno(br); if (index < 0) return ERR_PTR(index); p = kmalloc(sizeof(*p), GFP_KERNEL); if (p == NULL) return ERR_PTR(-ENOMEM); memset(p, 0, sizeof(*p)); p->br = br; dev_hold(dev); p->dev = dev; p->path_cost = cost; p->priority = 0x8000 >> BR_PORT_BITS; dev->br_port = p; p->port_no = index; br_init_port(p); p->state = BR_STATE_DISABLED; kobject_init(&p->kobj); return p; } int br_add_bridge(const char *name) { struct net_device *dev; int ret; dev = new_bridge_dev(name); if (!dev) return -ENOMEM; rtnl_lock(); if (strchr(dev->name, '%')) { ret = dev_alloc_name(dev, dev->name); if (ret < 0) goto err1; } ret = register_netdevice(dev); if (ret) goto err2; /* network device kobject is not setup until * after rtnl_unlock does it's hotplug magic. * so hold reference to avoid race. */ dev_hold(dev); rtnl_unlock(); ret = br_sysfs_addbr(dev); dev_put(dev); if (ret) unregister_netdev(dev); out: return ret; err2: free_netdev(dev); err1: rtnl_unlock(); goto out; } int br_del_bridge(const char *name) { struct net_device *dev; int ret = 0; rtnl_lock(); dev = __dev_get_by_name(name); if (dev == NULL) ret = -ENXIO; /* Could not find device */ else if (!(dev->priv_flags & IFF_EBRIDGE)) { /* Attempt to delete non bridge device! */ ret = -EPERM; } else if (dev->flags & IFF_UP) { /* Not shutdown yet. */ ret = -EBUSY; } else del_br(netdev_priv(dev)); rtnl_unlock(); return ret; } /* Mtu of the bridge pseudo-device 1500 or the minimum of the ports */ int br_min_mtu(const struct net_bridge *br) { const struct net_bridge_port *p; int mtu = 0; ASSERT_RTNL(); if (list_empty(&br->port_list)) mtu = 1500; else { list_for_each_entry(p, &br->port_list, list) { if (!mtu || p->dev->mtu < mtu) mtu = p->dev->mtu; } } return mtu; } /* * Recomputes features using slave's features */ void br_features_recompute(struct net_bridge *br) { struct net_bridge_port *p; unsigned long features, checksum; features = NETIF_F_SG | NETIF_F_FRAGLIST | NETIF_F_HIGHDMA | NETIF_F_TSO; checksum = NETIF_F_IP_CSUM; /* least commmon subset */ list_for_each_entry(p, &br->port_list, list) { if (!(p->dev->features & (NETIF_F_IP_CSUM|NETIF_F_NO_CSUM|NETIF_F_HW_CSUM))) checksum = 0; features &= p->dev->features; } br->dev->features = features | checksum | NETIF_F_LLTX; } /* called with RTNL */ int br_add_if(struct net_bridge *br, struct net_device *dev) { struct net_bridge_port *p; int err = 0; if (dev->flags & IFF_LOOPBACK || dev->type != ARPHRD_ETHER) return -EINVAL; if (dev->hard_start_xmit == br_dev_xmit) return -ELOOP; if (dev->br_port != NULL) return -EBUSY; if (IS_ERR(p = new_nbp(br, dev, br_initial_port_cost(dev)))) return PTR_ERR(p); if ((err = br_fdb_insert(br, p, dev->dev_addr))) destroy_nbp(p); else if ((err = br_sysfs_addif(p))) del_nbp(p); else { dev_set_promiscuity(dev, 1); list_add_rcu(&p->list, &br->port_list); spin_lock_bh(&br->lock); br_stp_recalculate_bridge_id(br); if ((br->dev->flags & IFF_UP) && (dev->flags & IFF_UP) && netif_carrier_ok(dev)) br_stp_enable_port(p); spin_unlock_bh(&br->lock); dev_set_mtu(br->dev, br_min_mtu(br)); } return err; } /* called with RTNL */ int br_del_if(struct net_bridge *br, struct net_device *dev) { struct net_bridge_port *p = dev->br_port; if (!p || p->br != br) return -EINVAL; br_sysfs_removeif(p); del_nbp(p); spin_lock_bh(&br->lock); br_stp_recalculate_bridge_id(br); br_features_recompute(br); spin_unlock_bh(&br->lock); return 0; } void __exit br_cleanup_bridges(void) { struct net_device *dev, *nxt; rtnl_lock(); for (dev = dev_base; dev; dev = nxt) { nxt = dev->next; if (dev->priv_flags & IFF_EBRIDGE) del_br(dev->priv); } rtnl_unlock(); }