#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/spinlock.h>
-#include <linux/if_bridge.h>
#include <linux/times.h>
+#include <linux/netdevice.h>
#include <linux/etherdevice.h>
+#include <linux/jhash.h>
#include <asm/atomic.h>
-#include <asm/uaccess.h>
#include "br_private.h"
-static kmem_cache_t *br_fdb_cache;
+static kmem_cache_t *br_fdb_cache __read_mostly;
+static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
+ const unsigned char *addr);
void __init br_fdb_init(void)
{
&& time_before_eq(fdb->ageing_timer + hold_time(br), jiffies);
}
-static inline void copy_fdb(struct __fdb_entry *ent,
- const struct net_bridge_fdb_entry *f)
-{
- memset(ent, 0, sizeof(struct __fdb_entry));
- memcpy(ent->mac_addr, f->addr.addr, ETH_ALEN);
- ent->port_no = f->dst?f->dst->port_no:0;
- ent->is_local = f->is_local;
- ent->ageing_timer_value = f->is_static ? 0
- : jiffies_to_clock_t(jiffies - f->ageing_timer);
-}
-
static __inline__ int br_mac_hash(const unsigned char *mac)
{
- unsigned long x;
-
- x = mac[0];
- x = (x << 2) ^ mac[1];
- x = (x << 2) ^ mac[2];
- x = (x << 2) ^ mac[3];
- x = (x << 2) ^ mac[4];
- x = (x << 2) ^ mac[5];
-
- x ^= x >> 8;
-
- return x & (BR_HASH_SIZE - 1);
+ return jhash(mac, ETH_ALEN, 0) & (BR_HASH_SIZE - 1);
}
static __inline__ void fdb_delete(struct net_bridge_fdb_entry *f)
{
- hlist_del(&f->hlist);
- list_del(&f->age_list);
+ hlist_del_rcu(&f->hlist);
br_fdb_put(f);
}
void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr)
{
- struct net_bridge *br;
+ struct net_bridge *br = p->br;
int i;
- int newhash = br_mac_hash(newaddr);
+
+ spin_lock_bh(&br->hash_lock);
- br = p->br;
- write_lock_bh(&br->hash_lock);
- for (i=0;i<BR_HASH_SIZE;i++) {
+ /* Search all chains since old address/hash is unknown */
+ for (i = 0; i < BR_HASH_SIZE; i++) {
struct hlist_node *h;
-
hlist_for_each(h, &br->hash[i]) {
- struct net_bridge_fdb_entry *f
- = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
+ struct net_bridge_fdb_entry *f;
+ f = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
if (f->dst == p && f->is_local) {
- memcpy(f->addr.addr, newaddr, ETH_ALEN);
- if (newhash != i) {
- hlist_del(&f->hlist);
- hlist_add_head(&f->hlist,
- &br->hash[newhash]);
+ /* maybe another port has same hw addr? */
+ struct net_bridge_port *op;
+ list_for_each_entry(op, &br->port_list, list) {
+ if (op != p &&
+ !compare_ether_addr(op->dev->dev_addr,
+ f->addr.addr)) {
+ f->dst = op;
+ goto insert;
+ }
}
- goto out;
+
+ /* delete old one */
+ fdb_delete(f);
+ goto insert;
}
}
}
- out:
- write_unlock_bh(&br->hash_lock);
+ insert:
+ /* insert new address, may fail if invalid address or dup. */
+ fdb_insert(br, p, newaddr);
+
+ spin_unlock_bh(&br->hash_lock);
}
void br_fdb_cleanup(unsigned long _data)
{
struct net_bridge *br = (struct net_bridge *)_data;
- struct list_head *l, *n;
- unsigned long delay;
-
- write_lock_bh(&br->hash_lock);
- delay = hold_time(br);
+ unsigned long delay = hold_time(br);
+ int i;
- list_for_each_safe(l, n, &br->age_list) {
- struct net_bridge_fdb_entry *f
- = list_entry(l, struct net_bridge_fdb_entry, age_list);
- unsigned long expires = f->ageing_timer + delay;
+ spin_lock_bh(&br->hash_lock);
+ for (i = 0; i < BR_HASH_SIZE; i++) {
+ struct net_bridge_fdb_entry *f;
+ struct hlist_node *h, *n;
- if (time_before_eq(expires, jiffies)) {
- if (!f->is_static) {
- pr_debug("expire age %lu jiffies %lu\n",
- f->ageing_timer, jiffies);
+ hlist_for_each_entry_safe(f, h, n, &br->hash[i], hlist) {
+ if (!f->is_static &&
+ time_before_eq(f->ageing_timer + delay, jiffies))
fdb_delete(f);
- }
- } else {
- mod_timer(&br->gc_timer, expires);
- break;
}
}
- write_unlock_bh(&br->hash_lock);
+ spin_unlock_bh(&br->hash_lock);
+
+ mod_timer(&br->gc_timer, jiffies + HZ/10);
}
void br_fdb_delete_by_port(struct net_bridge *br, struct net_bridge_port *p)
{
int i;
- write_lock_bh(&br->hash_lock);
- for (i=0;i<BR_HASH_SIZE;i++) {
+ spin_lock_bh(&br->hash_lock);
+ for (i = 0; i < BR_HASH_SIZE; i++) {
struct hlist_node *h, *g;
hlist_for_each_safe(h, g, &br->hash[i]) {
struct net_bridge_fdb_entry *f
= hlist_entry(h, struct net_bridge_fdb_entry, hlist);
- if (f->dst == p) {
- fdb_delete(f);
+ if (f->dst != p)
+ continue;
+
+ /*
+ * if multiple ports all have the same device address
+ * then when one port is deleted, assign
+ * the local entry to other port
+ */
+ if (f->is_local) {
+ struct net_bridge_port *op;
+ list_for_each_entry(op, &br->port_list, list) {
+ if (op != p &&
+ !compare_ether_addr(op->dev->dev_addr,
+ f->addr.addr)) {
+ f->dst = op;
+ goto skip_delete;
+ }
+ }
}
+
+ fdb_delete(f);
+ skip_delete: ;
}
}
- write_unlock_bh(&br->hash_lock);
+ spin_unlock_bh(&br->hash_lock);
}
-struct net_bridge_fdb_entry *br_fdb_get(struct net_bridge *br, unsigned char *addr)
+/* No locking or refcounting, assumes caller has no preempt (rcu_read_lock) */
+struct net_bridge_fdb_entry *__br_fdb_get(struct net_bridge *br,
+ const unsigned char *addr)
{
struct hlist_node *h;
+ struct net_bridge_fdb_entry *fdb;
- read_lock_bh(&br->hash_lock);
-
- hlist_for_each(h, &br->hash[br_mac_hash(addr)]) {
- struct net_bridge_fdb_entry *fdb
- = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
-
- if (!memcmp(fdb->addr.addr, addr, ETH_ALEN)) {
- if (has_expired(br, fdb))
- goto ret_null;
-
- atomic_inc(&fdb->use_count);
- read_unlock_bh(&br->hash_lock);
+ hlist_for_each_entry_rcu(fdb, h, &br->hash[br_mac_hash(addr)], hlist) {
+ if (!compare_ether_addr(fdb->addr.addr, addr)) {
+ if (unlikely(has_expired(br, fdb)))
+ break;
return fdb;
}
}
- ret_null:
- read_unlock_bh(&br->hash_lock);
+
return NULL;
}
+/* Interface used by ATM hook that keeps a ref count */
+struct net_bridge_fdb_entry *br_fdb_get(struct net_bridge *br,
+ unsigned char *addr)
+{
+ struct net_bridge_fdb_entry *fdb;
+
+ rcu_read_lock();
+ fdb = __br_fdb_get(br, addr);
+ if (fdb)
+ atomic_inc(&fdb->use_count);
+ rcu_read_unlock();
+ return fdb;
+}
+
+static void fdb_rcu_free(struct rcu_head *head)
+{
+ struct net_bridge_fdb_entry *ent
+ = container_of(head, struct net_bridge_fdb_entry, rcu);
+ kmem_cache_free(br_fdb_cache, ent);
+}
+
+/* Set entry up for deletion with RCU */
void br_fdb_put(struct net_bridge_fdb_entry *ent)
{
if (atomic_dec_and_test(&ent->use_count))
- kmem_cache_free(br_fdb_cache, ent);
+ call_rcu(&ent->rcu, fdb_rcu_free);
}
-int br_fdb_get_entries(struct net_bridge *br,
- unsigned char *_buf,
- int maxnum,
- int offset)
+/*
+ * Fill buffer with forwarding table records in
+ * the API format.
+ */
+int br_fdb_fillbuf(struct net_bridge *br, void *buf,
+ unsigned long maxnum, unsigned long skip)
{
- int i;
- int num;
- struct __fdb_entry *walk;
+ struct __fdb_entry *fe = buf;
+ int i, num = 0;
+ struct hlist_node *h;
+ struct net_bridge_fdb_entry *f;
- num = 0;
- walk = (struct __fdb_entry *)_buf;
-
- read_lock_bh(&br->hash_lock);
- for (i=0;i<BR_HASH_SIZE;i++) {
- struct hlist_node *h;
-
- hlist_for_each(h, &br->hash[i]) {
- struct net_bridge_fdb_entry *f
- = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
- struct __fdb_entry ent;
+ memset(buf, 0, maxnum*sizeof(struct __fdb_entry));
+ rcu_read_lock();
+ for (i = 0; i < BR_HASH_SIZE; i++) {
+ hlist_for_each_entry_rcu(f, h, &br->hash[i], hlist) {
if (num >= maxnum)
goto out;
if (has_expired(br, f))
continue;
- if (offset) {
- offset--;
+ if (skip) {
+ --skip;
continue;
}
- copy_fdb(&ent, f);
-
- atomic_inc(&f->use_count);
- read_unlock_bh(&br->hash_lock);
-
- if (copy_to_user(walk, &ent, sizeof(struct __fdb_entry)))
- return -EFAULT;
-
- read_lock_bh(&br->hash_lock);
-
- /* entry was deleted during copy_to_user */
- if (atomic_dec_and_test(&f->use_count)) {
- kmem_cache_free(br_fdb_cache, f);
- num = -EAGAIN;
- goto out;
- }
-
- /* entry changed address hash while copying */
- if (br_mac_hash(f->addr.addr) != i) {
- num = -EAGAIN;
- goto out;
- }
-
- num++;
- walk++;
+ /* convert from internal format to API */
+ memcpy(fe->mac_addr, f->addr.addr, ETH_ALEN);
+ fe->port_no = f->dst->port_no;
+ fe->is_local = f->is_local;
+ if (!f->is_static)
+ fe->ageing_timer_value = jiffies_to_clock_t(jiffies - f->ageing_timer);
+ ++fe;
+ ++num;
}
}
out:
- read_unlock_bh(&br->hash_lock);
+ rcu_read_unlock();
+
return num;
}
-int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
- const unsigned char *addr, int is_local)
+static inline struct net_bridge_fdb_entry *fdb_find(struct hlist_head *head,
+ const unsigned char *addr)
{
struct hlist_node *h;
struct net_bridge_fdb_entry *fdb;
- int hash = br_mac_hash(addr);
- int ret = 0;
-
- if (!is_valid_ether_addr(addr))
- return -EADDRNOTAVAIL;
-
- write_lock_bh(&br->hash_lock);
- hlist_for_each(h, &br->hash[hash]) {
- fdb = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
- if (!memcmp(fdb->addr.addr, addr, ETH_ALEN)) {
- /* attempt to update an entry for a local interface */
- if (unlikely(fdb->is_local)) {
- if (is_local)
- printk(KERN_INFO "%s: attempt to add"
- " interface with same source address.\n",
- source->dev->name);
- else if (net_ratelimit())
- printk(KERN_WARNING "%s: received packet with "
- " own address as source address\n",
- source->dev->name);
- ret = -EEXIST;
- goto out;
- }
-
- if (likely(!fdb->is_static || is_local)) {
- /* move to end of age list */
- list_del(&fdb->age_list);
- goto update;
- }
- goto out;
- }
+ hlist_for_each_entry_rcu(fdb, h, head, hlist) {
+ if (!compare_ether_addr(fdb->addr.addr, addr))
+ return fdb;
}
+ return NULL;
+}
+
+static struct net_bridge_fdb_entry *fdb_create(struct hlist_head *head,
+ struct net_bridge_port *source,
+ const unsigned char *addr,
+ int is_local)
+{
+ struct net_bridge_fdb_entry *fdb;
fdb = kmem_cache_alloc(br_fdb_cache, GFP_ATOMIC);
- if (unlikely(fdb == NULL)) {
- ret = -ENOMEM;
- goto out;
+ if (fdb) {
+ memcpy(fdb->addr.addr, addr, ETH_ALEN);
+ atomic_set(&fdb->use_count, 1);
+ hlist_add_head_rcu(&fdb->hlist, head);
+
+ fdb->dst = source;
+ fdb->is_local = is_local;
+ fdb->is_static = is_local;
+ fdb->ageing_timer = jiffies;
}
+ return fdb;
+}
- memcpy(fdb->addr.addr, addr, ETH_ALEN);
- atomic_set(&fdb->use_count, 1);
- hlist_add_head(&fdb->hlist, &br->hash[hash]);
+static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
+ const unsigned char *addr)
+{
+ struct hlist_head *head = &br->hash[br_mac_hash(addr)];
+ struct net_bridge_fdb_entry *fdb;
- if (!timer_pending(&br->gc_timer)) {
- br->gc_timer.expires = jiffies + hold_time(br);
- add_timer(&br->gc_timer);
- }
+ if (!is_valid_ether_addr(addr))
+ return -EINVAL;
+
+ fdb = fdb_find(head, addr);
+ if (fdb) {
+ /* it is okay to have multiple ports with same
+ * address, just use the first one.
+ */
+ if (fdb->is_local)
+ return 0;
+
+ printk(KERN_WARNING "%s adding interface with same address "
+ "as a received packet\n",
+ source->dev->name);
+ fdb_delete(fdb);
+ }
+
+ if (!fdb_create(head, source, addr, 1))
+ return -ENOMEM;
+
+ return 0;
+}
- update:
- fdb->dst = source;
- fdb->is_local = is_local;
- fdb->is_static = is_local;
- fdb->ageing_timer = jiffies;
- list_add_tail(&fdb->age_list, &br->age_list);
- out:
- write_unlock_bh(&br->hash_lock);
+int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
+ const unsigned char *addr)
+{
+ int ret;
+ spin_lock_bh(&br->hash_lock);
+ ret = fdb_insert(br, source, addr);
+ spin_unlock_bh(&br->hash_lock);
return ret;
}
+
+void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
+ const unsigned char *addr)
+{
+ struct hlist_head *head = &br->hash[br_mac_hash(addr)];
+ struct net_bridge_fdb_entry *fdb;
+
+ /* some users want to always flood. */
+ if (hold_time(br) == 0)
+ return;
+
+ fdb = fdb_find(head, addr);
+ if (likely(fdb)) {
+ /* attempt to update an entry for a local interface */
+ if (unlikely(fdb->is_local)) {
+ if (net_ratelimit())
+ printk(KERN_WARNING "%s: received packet with "
+ " own address as source address\n",
+ source->dev->name);
+ } else {
+ /* fastpath: update of existing entry */
+ fdb->dst = source;
+ fdb->ageing_timer = jiffies;
+ }
+ } else {
+ spin_lock(&br->hash_lock);
+ if (!fdb_find(head, addr))
+ fdb_create(head, source, addr, 0);
+ /* else we lose race and someone else inserts
+ * it first, don't bother updating
+ */
+ spin_unlock(&br->hash_lock);
+ }
+}
git://git.onelab.eu / linux-2.6.git / blobdiff