X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=net%2Fcore%2Fdev_mcast.c;h=99aece1aeccff9aa950c3b8bb08385b8dd2b2b25;hb=40b77c943468236c6dfad3e7b94348fe70c70331;hp=aa38100601fb31d2c6d73e83ddb30f62d884c45a;hpb=4aabab2181f20560948c2045ce1faaa9ac1507a8;p=linux-2.6

diff --git a/net/core/dev_mcast.c b/net/core/dev_mcast.c
index aa38100601..99aece1aec 100644
--- a/net/core/dev_mcast.c
+++ b/net/core/dev_mcast.c
@@ -102,17 +102,80 @@ int dev_mc_add(struct net_device *dev, void *addr, int alen, int glbl)
 	return err;
 }
 
-/*
- *	Discard multicast list when a device is downed
+/**
+ *	dev_mc_sync	- Synchronize device's multicast list to another device
+ *	@to: destination device
+ *	@from: source device
+ *
+ * 	Add newly added addresses to the destination device and release
+ * 	addresses that have no users left. The source device must be
+ * 	locked by netif_tx_lock_bh.
+ *
+ *	This function is intended to be called from the dev->set_multicast_list
+ *	function of layered software devices.
  */
+int dev_mc_sync(struct net_device *to, struct net_device *from)
+{
+	struct dev_addr_list *da;
+	int err = 0;
+
+	netif_tx_lock_bh(to);
+	for (da = from->mc_list; da != NULL; da = da->next) {
+		if (!da->da_synced) {
+			err = __dev_addr_add(&to->mc_list, &to->mc_count,
+					     da->da_addr, da->da_addrlen, 0);
+			if (err < 0)
+				break;
+			da->da_synced = 1;
+			da->da_users++;
+		} else if (da->da_users == 1) {
+			__dev_addr_delete(&to->mc_list, &to->mc_count,
+					  da->da_addr, da->da_addrlen, 0);
+			__dev_addr_delete(&from->mc_list, &from->mc_count,
+					  da->da_addr, da->da_addrlen, 0);
+		}
+	}
+	if (!err)
+		__dev_set_rx_mode(to);
+	netif_tx_unlock_bh(to);
+
+	return err;
+}
+EXPORT_SYMBOL(dev_mc_sync);
+
 
-void dev_mc_discard(struct net_device *dev)
+/**
+ * 	dev_mc_unsync	- Remove synchronized addresses from the destination
+ * 			  device
+ *	@to: destination device
+ *	@from: source device
+ *
+ * 	Remove all addresses that were added to the destination device by
+ * 	dev_mc_sync(). This function is intended to be called from the
+ * 	dev->stop function of layered software devices.
+ */
+void dev_mc_unsync(struct net_device *to, struct net_device *from)
 {
-	netif_tx_lock_bh(dev);
-	__dev_addr_discard(&dev->mc_list);
-	dev->mc_count = 0;
-	netif_tx_unlock_bh(dev);
+	struct dev_addr_list *da;
+
+	netif_tx_lock_bh(from);
+	netif_tx_lock_bh(to);
+
+	for (da = from->mc_list; da != NULL; da = da->next) {
+		if (!da->da_synced)
+			continue;
+		__dev_addr_delete(&to->mc_list, &to->mc_count,
+				  da->da_addr, da->da_addrlen, 0);
+		da->da_synced = 0;
+		__dev_addr_delete(&from->mc_list, &from->mc_count,
+				  da->da_addr, da->da_addrlen, 0);
+	}
+	__dev_set_rx_mode(to);
+
+	netif_tx_unlock_bh(to);
+	netif_tx_unlock_bh(from);
 }
+EXPORT_SYMBOL(dev_mc_unsync);
 
 #ifdef CONFIG_PROC_FS
 static void *dev_mc_seq_start(struct seq_file *seq, loff_t *pos)