2 files changed, 101 insertions, 34 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index c9c593e1ba6f..edaff2720e10 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2962,6 +2962,102 @@ int dev_unicast_add(struct net_device *dev, void *addr, int alen)
 }
 EXPORT_SYMBOL(dev_unicast_add);
 
+int __dev_addr_sync(struct dev_addr_list **to, int *to_count,
+                    struct dev_addr_list **from, int *from_count)
+{
+        struct dev_addr_list *da, *next;
+        int err = 0;
+
+        da = *from;
+        while (da != NULL) {
+                next = da->next;
+                if (!da->da_synced) {
+                        err = __dev_addr_add(to, to_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, to_count,
+                                          da->da_addr, da->da_addrlen, 0);
+                        __dev_addr_delete(from, from_count,
+                                          da->da_addr, da->da_addrlen, 0);
+                }
+                da = next;
+        }
+        return err;
+}
+
+void __dev_addr_unsync(struct dev_addr_list **to, int *to_count,
+                       struct dev_addr_list **from, int *from_count)
+{
+        struct dev_addr_list *da, *next;
+
+        da = *from;
+        while (da != NULL) {
+                next = da->next;
+                if (da->da_synced) {
+                        __dev_addr_delete(to, to_count,
+                                          da->da_addr, da->da_addrlen, 0);
+                        da->da_synced = 0;
+                        __dev_addr_delete(from, from_count,
+                                          da->da_addr, da->da_addrlen, 0);
+                }
+                da = next;
+        }
+}
+
+/**
+ *      dev_unicast_sync - Synchronize device's unicast 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_rx_mode
+ *      function of layered software devices.
+ */
+int dev_unicast_sync(struct net_device *to, struct net_device *from)
+{
+        int err = 0;
+
+        netif_tx_lock_bh(to);
+        err = __dev_addr_sync(&to->uc_list, &to->uc_count,
+                              &from->uc_list, &from->uc_count);
+        if (!err)
+                __dev_set_rx_mode(to);
+        netif_tx_unlock_bh(to);
+        return err;
+}
+EXPORT_SYMBOL(dev_unicast_sync);
+
+/**
+ *      dev_unicast_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_unicast_sync(). This function is intended to be called from the
+ *      dev->stop function of layered software devices.
+ */
+void dev_unicast_unsync(struct net_device *to, struct net_device *from)
+{
+        netif_tx_lock_bh(from);
+        netif_tx_lock_bh(to);
+
+        __dev_addr_unsync(&to->uc_list, &to->uc_count,
+                          &from->uc_list, &from->uc_count);
+        __dev_set_rx_mode(to);
+
+        netif_tx_unlock_bh(to);
+        netif_tx_unlock_bh(from);
+}
+EXPORT_SYMBOL(dev_unicast_unsync);
+
 static void __dev_addr_discard(struct dev_addr_list **list)
 {
         struct dev_addr_list *tmp;
diff --git a/net/core/dev_mcast.c b/net/core/dev_mcast.c
index cadbfbf7e7f5..cec582563e0d 100644
--- a/net/core/dev_mcast.c
+++ b/net/core/dev_mcast.c
@@ -113,32 +113,15 @@ int dev_mc_add(struct net_device *dev, void *addr, int alen, int glbl)
  *      locked by netif_tx_lock_bh.
  *
  *      This function is intended to be called from the dev->set_multicast_list
- *      function of layered software devices.
+ *      or dev->set_rx_mode function of layered software devices.
  */
 int dev_mc_sync(struct net_device *to, struct net_device *from)
 {
-        struct dev_addr_list *da, *next;
         int err = 0;
 
         netif_tx_lock_bh(to);
-        da = from->mc_list;
-        while (da != NULL) {
-                next = 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);
-                }
-                da = next;
-        }
+        err = __dev_addr_sync(&to->mc_list, &to->mc_count,
+                              &from->mc_list, &from->mc_count);
         if (!err)
                 __dev_set_rx_mode(to);
         netif_tx_unlock_bh(to);
@@ -160,23 +143,11 @@ EXPORT_SYMBOL(dev_mc_sync);
  */
 void dev_mc_unsync(struct net_device *to, struct net_device *from)
 {
-        struct dev_addr_list *da, *next;
-
         netif_tx_lock_bh(from);
         netif_tx_lock_bh(to);
 
-        da = from->mc_list;
-        while (da != NULL) {
-                next = da->next;
-                if (da->da_synced) {
-                        __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);
-                }
-                da = next;
-        }
+        __dev_addr_unsync(&to->mc_list, &to->mc_count,
+                          &from->mc_list, &from->mc_count);
         __dev_set_rx_mode(to);
 
         netif_tx_unlock_bh(to);