Linux-2.6.12-rc2v2.6.12-rc2

Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.

Let it rip!

1 files changed, 368 insertions, 0 deletions

diff --git a/net/bridge/br_fdb.c b/net/bridge/br_fdb.c
new file mode 100644
index 000000000000..e6c2200b7ca3
--- /dev/null
+++ b/net/bridge/br_fdb.c
@@ -0,0 +1,368 @@
+/*
+ *      Forwarding database
+ *      Linux ethernet bridge
+ *
+ *      Authors:
+ *      Lennert Buytenhek               <buytenh@gnu.org>
+ *
+ *      $Id: br_fdb.c,v 1.6 2002/01/17 00:57:07 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/init.h>
+#include <linux/spinlock.h>
+#include <linux/times.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/jhash.h>
+#include <asm/atomic.h>
+#include "br_private.h"
+
+static kmem_cache_t *br_fdb_cache;
+static int fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
+                      const unsigned char *addr);
+
+void __init br_fdb_init(void)
+{
+        br_fdb_cache = kmem_cache_create("bridge_fdb_cache",
+                                         sizeof(struct net_bridge_fdb_entry),
+                                         0,
+                                         SLAB_HWCACHE_ALIGN, NULL, NULL);
+}
+
+void __exit br_fdb_fini(void)
+{
+        kmem_cache_destroy(br_fdb_cache);
+}
+
+
+/* if topology_changing then use forward_delay (default 15 sec)
+ * otherwise keep longer (default 5 minutes)
+ */
+static __inline__ unsigned long hold_time(const struct net_bridge *br)
+{
+        return br->topology_change ? br->forward_delay : br->ageing_time;
+}
+
+static __inline__ int has_expired(const struct net_bridge *br,
+                                  const struct net_bridge_fdb_entry *fdb)
+{
+        return !fdb->is_static 
+                && time_before_eq(fdb->ageing_timer + hold_time(br), jiffies);
+}
+
+static __inline__ int br_mac_hash(const unsigned char *mac)
+{
+        return jhash(mac, ETH_ALEN, 0) & (BR_HASH_SIZE - 1);
+}
+
+static __inline__ void fdb_delete(struct net_bridge_fdb_entry *f)
+{
+        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 = p->br;
+        int i;
+        
+        spin_lock_bh(&br->hash_lock);
+
+        /* 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;
+
+                        f = hlist_entry(h, struct net_bridge_fdb_entry, hlist);
+                        if (f->dst == p && f->is_local) {
+                                /* maybe another port has same hw addr? */
+                                struct net_bridge_port *op;
+                                list_for_each_entry(op, &br->port_list, list) {
+                                        if (op != p && 
+                                            !memcmp(op->dev->dev_addr,
+                                                    f->addr.addr, ETH_ALEN)) {
+                                                f->dst = op;
+                                                goto insert;
+                                        }
+                                }
+
+                                /* delete old one */
+                                fdb_delete(f);
+                                goto insert;
+                        }
+                }
+        }
+ 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;
+        unsigned long delay = hold_time(br);
+        int i;
+
+        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;
+
+                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);
+                }
+        }
+        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;
+
+        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) 
+                                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 && 
+                                            !memcmp(op->dev->dev_addr,
+                                                    f->addr.addr, ETH_ALEN)) {
+                                                f->dst = op;
+                                                goto skip_delete;
+                                        }
+                                }
+                        }
+
+                        fdb_delete(f);
+                skip_delete: ;
+                }
+        }
+        spin_unlock_bh(&br->hash_lock);
+}
+
+/* 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;
+
+        hlist_for_each_entry_rcu(fdb, h, &br->hash[br_mac_hash(addr)], hlist) {
+                if (!memcmp(fdb->addr.addr, addr, ETH_ALEN)) {
+                        if (unlikely(has_expired(br, fdb)))
+                                break;
+                        return fdb;
+                }
+        }
+
+        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))
+                call_rcu(&ent->rcu, fdb_rcu_free);
+}
+
+/*
+ * 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)
+{
+        struct __fdb_entry *fe = buf;
+        int i, num = 0;
+        struct hlist_node *h;
+        struct net_bridge_fdb_entry *f;
+
+        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 (skip) {
+                                --skip;
+                                continue;
+                        }
+
+                        /* 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:
+        rcu_read_unlock();
+
+        return num;
+}
+
+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;
+
+        hlist_for_each_entry_rcu(fdb, h, head, hlist) {
+                if (!memcmp(fdb->addr.addr, addr, ETH_ALEN))
+                        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 (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;
+}
+
+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 (!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;
+}
+
+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;
+
+        rcu_read_lock();
+        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_bh(&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_bh(&br->hash_lock);
+        }
+        rcu_read_unlock();
+}