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/*
* Userspace interface
* Linux ethernet bridge
*
* Authors:
* Lennert Buytenhek <buytenh@gnu.org>
*
* 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/netpoll.h>
#include <linux/ethtool.h>
#include <linux/if_arp.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/rtnetlink.h>
#include <linux/if_ether.h>
#include <linux/slab.h>
#include <net/sock.h>
#include "br_private.h"
/*
* Determine initial path cost based on speed.
* using recommendations from 802.1d standard
*
* Since driver might sleep need to not be holding any locks.
*/
static int port_cost(struct net_device *dev)
{
if (dev->ethtool_ops && dev->ethtool_ops->get_settings) {
struct ethtool_cmd ecmd = { .cmd = ETHTOOL_GSET, };
if (!dev->ethtool_ops->get_settings(dev, &ecmd)) {
switch(ecmd.speed) {
case SPEED_10000:
return 2;
case SPEED_1000:
return 4;
case SPEED_100:
return 19;
case SPEED_10:
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 */
}
/*
* Check for port carrier transistions.
* Called from work queue to allow for calling functions that
* might sleep (such as speed check), and to debounce.
*/
void br_port_carrier_check(struct net_bridge_port *p)
{
struct net_device *dev = p->dev;
struct net_bridge *br = p->br;
if (netif_carrier_ok(dev))
p->path_cost = port_cost(dev);
if (netif_running(br->dev)) {
spin_lock_bh(&br->lock);
if (netif_carrier_ok(dev)) {
if (p->state == BR_STATE_DISABLED)
br_stp_enable_port(p);
} else {
if (p->state != BR_STATE_DISABLED)
br_stp_disable_port(p);
}
spin_unlock_bh(&br->lock);
}
}
static void release_nbp(struct kobject *kobj)
{
struct net_bridge_port *p
= container_of(kobj, struct net_bridge_port, kobj);
kfree(p);
}
static struct kobj_type brport_ktype = {
#ifdef CONFIG_SYSFS
.sysfs_ops = &brport_sysfs_ops,
#endif
.release = release_nbp,
};
static void destroy_nbp(struct net_bridge_port *p)
{
struct net_device *dev = p->dev;
p->br = NULL;
p->dev = NULL;
dev_put(dev);
kobject_put(&p->kobj);
}
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);
}
/* Delete port(interface) from bridge is done in two steps.
* via RCU. First step, marks device as down. That deletes
* all the timers and stops new packets from flowing through.
*
* Final cleanup doesn't occur until after all CPU's finished
* processing packets.
*
* Protected from multiple admin operations by RTNL mutex
*/
static void del_nbp(struct net_bridge_port *p)
{
struct net_bridge *br = p->br;
struct net_device *dev = p->dev;
sysfs_remove_link(br->ifobj, p->dev->name);
dev_set_promiscuity(dev, -1);
spin_lock_bh(&br->lock);
br_stp_disable_port(p);
spin_unlock_bh(&br->lock);
br_ifinfo_notify(RTM_DELLINK, p);
br_fdb_delete_by_port(br, p, 1);
list_del_rcu(&p->list);
netdev_rx_handler_unregister(dev);
rcu_assign_pointer(dev->br_port, NULL);
br_multicast_del_port(p);
kobject_uevent(&p->kobj, KOBJ_REMOVE);
kobject_del(&p->kobj);
br_netpoll_disable(br, dev);
call_rcu(&p->rcu, destroy_nbp_rcu);
}
/* called with RTNL */
static void del_br(struct net_bridge *br, struct list_head *head)
{
struct net_bridge_port *p, *n;
list_for_each_entry_safe(p, n, &br->port_list, list) {
del_nbp(p);
}
br_netpoll_cleanup(br->dev);
del_timer_sync(&br->gc_timer);
br_sysfs_delbr(br->dev);
unregister_netdevice_queue(br->dev, head);
}
static struct net_device *new_bridge_dev(struct net *net, 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;
dev_net_set(dev, net);
br = netdev_priv(dev);
br->dev = dev;
br->stats = alloc_percpu(struct br_cpu_netstats);
if (!br->stats) {
free_netdev(dev);
return NULL;
}
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;
memcpy(br->group_addr, br_group_address, ETH_ALEN);
br->feature_mask = dev->features;
br->stp_enabled = BR_NO_STP;
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;
br_netfilter_rtable_init(br);
br_stp_timer_init(br);
br_multicast_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 = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
GFP_KERNEL);
if (!inuse)
return -ENOMEM;
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 but without bridge lock */
static struct net_bridge_port *new_nbp(struct net_bridge *br,
struct net_device *dev)
{
int index;
struct net_bridge_port *p;
index = find_portno(br);
if (index < 0)
return ERR_PTR(index);
p = kzalloc(sizeof(*p), GFP_KERNEL);
if (p == NULL)
return ERR_PTR(-ENOMEM);
p->br = br;
dev_hold(dev);
p->dev = dev;
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