|  | /* | 
|  | *	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; | 
|  |  | 
|  | dev->br_port = NULL; | 
|  | 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_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; | 
|  | } | 
|  |  | 
|  | /* 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); | 
|  | 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(); | 
|  |  | 
|  | } |