[ATM]: [lec] add reference counting to lec_arp entries

Signed-off-by: Chas Williams <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/atm/lec.c

···
 					    struct sk_buff *skb));
 static void lec_vcc_close(struct lec_priv *priv, struct atm_vcc *vcc);
 
+/* must be done under lec_arp_lock */
+static inline void lec_arp_hold(struct lec_arp_table *entry)
+{
+	atomic_inc(&entry->usage);
+}
+
+static inline void lec_arp_put(struct lec_arp_table *entry)
+{
+	if (atomic_dec_and_test(&entry->usage))
+		kfree(entry);
+}
+
+
 static struct lane2_ops lane2_ops = {
 	lane2_resolve,		/* resolve,             spec 3.1.3 */
 	lane2_associate_req,	/* associate_req,       spec 3.1.4 */
···
 			entry = lec_arp_find(priv, src);
 			if (entry && entry->vcc != vcc) {
 				lec_arp_remove(priv, entry);
-				kfree(entry);
+				lec_arp_put(entry);
 			}
 		}
 		spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
···
 	for (i = 0; i < LEC_ARP_TABLE_SIZE; i++) {
 		hlist_for_each_entry_safe(entry, node, next, &priv->lec_arp_tables[i], next) {
 			lec_arp_remove(priv, entry);
-			kfree(entry);
+			lec_arp_put(entry);
 		}
 		INIT_HLIST_HEAD(&priv->lec_arp_tables[i]);
 	}
···
 		del_timer_sync(&entry->timer);
 		lec_arp_clear_vccs(entry);
 		hlist_del(&entry->next);
-		kfree(entry);
+		lec_arp_put(entry);
 	}
 	INIT_HLIST_HEAD(&priv->lec_arp_empty_ones);
 
···
 		del_timer_sync(&entry->timer);
 		lec_arp_clear_vccs(entry);
 		hlist_del(&entry->next);
-		kfree(entry);
+		lec_arp_put(entry);
 	}
 	INIT_HLIST_HEAD(&priv->lec_no_forward);
 
···
 		/* No timer, LANEv2 7.1.20 and 2.3.5.3 */
 		lec_arp_clear_vccs(entry);
 		hlist_del(&entry->next);
-		kfree(entry);
+		lec_arp_put(entry);
 	}
 	INIT_HLIST_HEAD(&priv->mcast_fwds);
 	priv->mcast_vcc = NULL;
···
 	to_return->last_used = jiffies;
 	to_return->priv = priv;
 	skb_queue_head_init(&to_return->tx_wait);
+	atomic_set(&to_return->usage, 1);
 	return to_return;
 }
 
···
 	spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
 
 	lec_arp_clear_vccs(to_remove);
-	kfree(to_remove);
+	lec_arp_put(to_remove);
 }
 
 /*
···
 				/* Remove entry */
 				DPRINTK("LEC:Entry timed out\n");
 				lec_arp_remove(priv, entry);
-				kfree(entry);
+				lec_arp_put(entry);
 			} else {
 				/* Something else */
 				if ((entry->status == ESI_VC_PENDING ||
···
 			    && (permanent ||
 				!(entry->flags & LEC_PERMANENT_FLAG))) {
 				lec_arp_remove(priv, entry);
-				kfree(entry);
+				lec_arp_put(entry);
 			}
 			spin_unlock_irqrestore(&priv->lec_arp_lock, flags);
 			return 0;
···
 					tmp->old_push = entry->old_push;
 					tmp->last_used = jiffies;
 					del_timer(&entry->timer);
-					kfree(entry);
+					lec_arp_put(entry);
 					entry = tmp;
 				} else {
 					entry->status = ESI_FORWARD_DIRECT;
···
 		hlist_for_each_entry_safe(entry, node, next, &priv->lec_arp_tables[i], next) {
 			if (vcc == entry->vcc) {
 				lec_arp_remove(priv, entry);
-				kfree(entry);
+				lec_arp_put(entry);
 				if (priv->mcast_vcc == vcc) {
 					priv->mcast_vcc = NULL;
 				}
···
 			lec_arp_clear_vccs(entry);
 			del_timer(&entry->timer);
 			hlist_del(&entry->next);
-			kfree(entry);
+			lec_arp_put(entry);
 		}
 	}
 
···
 			lec_arp_clear_vccs(entry);
 			del_timer(&entry->timer);
 			hlist_del(&entry->next);
-			kfree(entry);
+			lec_arp_put(entry);
 		}
 	}
 
···
 			lec_arp_clear_vccs(entry);
 			/* No timer, LANEv2 7.1.20 and 2.3.5.3 */
 			hlist_del(&entry->next);
-			kfree(entry);
+			lec_arp_put(entry);
 		}
 	}
 
···
 			/* We might have got an entry */
 			if ((tmp = lec_arp_find(priv, src))) {
 				lec_arp_remove(priv, tmp);
-				kfree(tmp);
+				lec_arp_put(tmp);
 			}
 			hlist_del(&entry->next);
 			lec_arp_add(priv, entry);

net/atm/lec_arpc.h

···
 					 * the length of the tlvs array
 					 */
 	struct sk_buff_head tx_wait;	/* wait queue for outgoing packets */
+	atomic_t usage;			/* usage count */
 };
 
 /*