diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/dev_mcast.c | 75 |
1 files changed, 75 insertions, 0 deletions
diff --git a/net/core/dev_mcast.c b/net/core/dev_mcast.c index aa38100601f..235a2a8a0d0 100644 --- a/net/core/dev_mcast.c +++ b/net/core/dev_mcast.c @@ -102,6 +102,81 @@ int dev_mc_add(struct net_device *dev, void *addr, int alen, int glbl) return err; } +/** + * 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); + + +/** + * 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) +{ + 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); + /* * Discard multicast list when a device is downed */ |