In order to avoid all table update, and only remove or add new
address, the auxiliary function exists, named __hw_addr_sync_dev().
It allows end driver do nothing when nothing changed and add/rm when
concrete address is firstly added or lastly removed. But it doesn't
include cases when an address of real device or vlan was reused by
other vlans or vlan/macval devices.
For handaling events when address was reused/unreused the patch adds
new auxiliary routine - __hw_addr_ref_sync_dev(). It allows to do
nothing when nothing was changed and do updates only for an address
being added/reused/deleted/unreused. Thus, clone address changes for
vlans can be mirrored in the table. The function is exclusive with
__hw_addr_sync_dev(). It's responsibility of the end driver to
identify address vlan device, if it needs so.
Signed-off-by: Ivan Khoronzhuk <ivan.khoronzhuk@xxxxxxxxxx>
---
include/linux/netdevice.h | 10 ++++
net/core/dev_addr_lists.c | 97 +++++++++++++++++++++++++++++++++++++++
2 files changed, 107 insertions(+)
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 857f8abf7b91..487fa5e0e165 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -4068,6 +4068,16 @@ int __hw_addr_sync_dev(struct netdev_hw_addr_list *list,
int (*sync)(struct net_device *, const unsigned char *),
int (*unsync)(struct net_device *,
const unsigned char *));
+int __hw_addr_ref_sync_dev(struct netdev_hw_addr_list *list,
+ struct net_device *dev,
+ int (*sync)(struct net_device *,
+ const unsigned char *, int),
+ int (*unsync)(struct net_device *,
+ const unsigned char *, int));
+void __hw_addr_ref_unsync_dev(struct netdev_hw_addr_list *list,
+ struct net_device *dev,
+ int (*unsync)(struct net_device *,
+ const unsigned char *, int));
void __hw_addr_unsync_dev(struct netdev_hw_addr_list *list,
struct net_device *dev,
int (*unsync)(struct net_device *,
diff --git a/net/core/dev_addr_lists.c b/net/core/dev_addr_lists.c
index d884d8f5f0e5..81a8cd4ea3bd 100644
--- a/net/core/dev_addr_lists.c
+++ b/net/core/dev_addr_lists.c
@@ -277,6 +277,103 @@ int __hw_addr_sync_dev(struct netdev_hw_addr_list *list,
}
EXPORT_SYMBOL(__hw_addr_sync_dev);
+/**
+ * __hw_addr_ref_sync_dev - Synchronize device's multicast address list taking
+ * into account references
+ * @list: address list to synchronize
+ * @dev: device to sync
+ * @sync: function to call if address or reference on it should be added
+ * @unsync: function to call if address or some reference on it should removed
+ *
+ * This function is intended to be called from the ndo_set_rx_mode
+ * function of devices that require explicit address or references on it
+ * add/remove notifications. The unsync function may be NULL in which case
+ * the addresses or references on it requiring removal will simply be
+ * removed without any notification to the device. That is responsibility of
+ * the driver to identify and distribute address or references on it between
+ * internal address tables.
+ **/
+int __hw_addr_ref_sync_dev(struct netdev_hw_addr_list *list,
+ struct net_device *dev,
+ int (*sync)(struct net_device *,
+ const unsigned char *, int),
+ int (*unsync)(struct net_device *,
+ const unsigned char *, int))
+{
+ struct netdev_hw_addr *ha, *tmp;
+ int err, ref_cnt;
+
+ /* first go through and flush out any unsynced/stale entries */
+ list_for_each_entry_safe(ha, tmp, &list->list, list) {
+ /* sync if address is not used */
+ if ((ha->sync_cnt << 1) <= ha->refcount)
+ continue;
+
+ /* if fails defer unsyncing address */
+ ref_cnt = ha->refcount - ha->sync_cnt;
+ if (unsync && unsync(dev, ha->addr, ref_cnt))
+ continue;
+
+ ha->refcount = (ref_cnt << 1) + 1;
+ ha->sync_cnt = ref_cnt;
+ __hw_addr_del_entry(list, ha, false, false);
+ }
+
+ /* go through and sync updated/new entries to the list */
+ list_for_each_entry_safe(ha, tmp, &list->list, list) {
+ /* sync if address added or reused */
+ if ((ha->sync_cnt << 1) >= ha->refcount)
+ continue;
+
+ ref_cnt = ha->refcount - ha->sync_cnt;
+ err = sync(dev, ha->addr, ref_cnt);
+ if (err)
+ return err;
+
+ ha->refcount = ref_cnt << 1;
+ ha->sync_cnt = ref_cnt;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(__hw_addr_ref_sync_dev);
+
+/**
+ * __hw_addr_ref_unsync_dev - Remove synchronized addresses and references on
+ * it from device
+ * @list: address list to remove synchronized addresses (references on it) from
+ * @dev: device to sync
+ * @unsync: function to call if address and references on it should be removed
+ *
+ * Remove all addresses that were added to the device by
+ * __hw_addr_ref_sync_dev(). This function is intended to be called from the
+ * ndo_stop or ndo_open functions on devices that require explicit address (or
+ * references on it) add/remove notifications. If the unsync function pointer
+ * is NULL then this function can be used to just reset the sync_cnt for the
+ * addresses in the list.
+ **/
+void __hw_addr_ref_unsync_dev(struct netdev_hw_addr_list *list,
+ struct net_device *dev,
+ int (*unsync)(struct net_device *,
+ const unsigned char *, int))
+{
+ struct netdev_hw_addr *ha, *tmp;
+
+ list_for_each_entry_safe(ha, tmp, &list->list, list) {
+ if (!ha->sync_cnt)
+ continue;
+
+ /* if fails defer unsyncing address */
+ if (unsync && unsync(dev, ha->addr, ha->sync_cnt))
+ continue;
+
+ ha->refcount -= ha->sync_cnt - 1;
+ ha->sync_cnt = 0;
+ __hw_addr_del_entry(list, ha, false, false);
+ }
+}
+EXPORT_SYMBOL(__hw_addr_ref_unsync_dev);
+
/**
* __hw_addr_unsync_dev - Remove synchronized addresses from device
* @list: address list to remove synchronized addresses from
--
2.17.1
