;while ((n = *np) != null)
if ((long)(n->used - n->confirmed) < 0)
n->used = n->confirmed;
if (atomic_read(&n->ref**t) == 1 &&
(state == nud_failed || now - n->used > n->parms->gc_staletime))
if (n->nud_state&nud_reachable &&
now - n->confirmed > n->parms->reachable_time)
write_unlock(&n->lock);
next_elt:
np = &n->next;}}
mod_timer(&tbl->gc_timer, now + tbl->gc_interval);
write_unlock(&tbl->lock);
}int arp_bind_neighbour(struct dst_entry *dst) 將鄰居繫結給指定路由
return 0;
}static inline struct neighbour *
__neigh_lookup_errno(struct neigh_table *tbl, const void *pkey,
struct ***_device *dev)
struct neighbour *neigh_lookup(struct neigh_table *tbl, const void *pkey,
struct ***_device *dev)
}read_unlock_bh(&tbl->lock);
return n;
}static u32 arp_hash(const void *pkey, const struct ***_device *dev)
struct neighbour * neigh_create(struct neigh_table *tbl, const void *pkey,
struct ***_device *dev)
/* device specific setup. */
if (n->parms && n->parms->neigh_setup &&
(error = n->parms->neigh_setup(n)) < 0)
n->confirmed = jiffies - (n->parms->base_reachable_time<<1);
hash_val = tbl->hash(pkey, dev);
write_lock_bh(&tbl->lock);
for (n1 = tbl->hash_buckets[hash_val]; n1; n1 = n1->next)
}n->next = tbl->hash_buckets[hash_val];
tbl->hash_buckets[hash_val] = n; 插入索引鏈
n->dead = 0;
neigh_hold(n);
write_unlock_bh(&tbl->lock);
neigh_printk2("neigh %p is created./n", n);
return n;
}static struct neighbour *neigh_alloc(struct neigh_table *tbl) 分配鄰居結構
n = kmem_cache_alloc(tbl->kmem_cachep, slab_atomic);
if (n == null)
return null;
memset(n, 0, tbl->entry_size);
skb_queue_head_init(&n->arp_queue); 當鄰居的位址尚未解析時,
發向該鄰居的包緩衝在該佇列中
n->lock = rw_lock_unlocked;
n->updated = n->used = now;
n->nud_state = nud_none;
n->output = neigh_blackhole; 鄰居的ip包注入口
n->parms = &tbl->parms; 繼承鄰居表的引數
init_timer(&n->timer);
n->timer.function = neigh_timer_handler; 接收超時臨視器
n->timer.data = (unsigned long)n;
tbl->stats.allocs++;
neigh_glbl_allocs++;
tbl->entries++;
n->tbl = tbl;
atomic_set(&n->ref**t, 1);
n->dead = 1;
return n;
}static int neigh_blackhole(struct sk_buff *skb)
static int neigh_forced_gc(struct neigh_table *tbl) 強制釋放鄰居
{int shrunk = 0;
int i;
for (i=0; i<=neigh_hashmask; i++) {
struct neighbour *n, **np;
np = &tbl->hash_buckets
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