vlan: introduce vid list with reference counting

This allows to keep track of vids needed to be in rx vlan filters of
devices even if they are used in bond/team etc.

vlan_info as well as vlan_group previously was, is allocated when first
vid is added and dealocated whan last vid is deleted.

vlan_group definition is moved to private header.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 27 insertions, 3 deletions

diff --git a/net/8021q/vlan.h b/net/8021q/vlan.h
index d3c4ea4a383..28d8dc20cb6 100644
--- a/net/8021q/vlan.h
+++ b/net/8021q/vlan.h
@@ -3,6 +3,7 @@
 
 #include <linux/if_vlan.h>
 #include <linux/u64_stats_sync.h>
+#include <linux/list.h>
 
 
 /**
@@ -74,6 +75,29 @@ static inline struct vlan_dev_priv *vlan_dev_priv(const struct net_device *dev)
 	return netdev_priv(dev);
 }
 
+/* if this changes, algorithm will have to be reworked because this
+ * depends on completely exhausting the VLAN identifier space.  Thus
+ * it gives constant time look-up, but in many cases it wastes memory.
+ */
+#define VLAN_GROUP_ARRAY_SPLIT_PARTS  8
+#define VLAN_GROUP_ARRAY_PART_LEN     (VLAN_N_VID/VLAN_GROUP_ARRAY_SPLIT_PARTS)
+
+struct vlan_group {
+	unsigned int		nr_vlan_devs;
+	struct hlist_node	hlist;	/* linked list */
+	struct net_device **vlan_devices_arrays[VLAN_GROUP_ARRAY_SPLIT_PARTS];
+};
+
+struct vlan_info {
+	struct net_device	*real_dev; /* The ethernet(like) device
+					    * the vlan is attached to.
+					    */
+	struct vlan_group	grp;
+	struct list_head	vid_list;
+	unsigned int		nr_vids;
+	struct rcu_head		rcu;
+};
+
 static inline struct net_device *vlan_group_get_device(struct vlan_group *vg,
 						       u16 vlan_id)
 {
@@ -97,10 +121,10 @@ static inline void vlan_group_set_device(struct vlan_group *vg,
 static inline struct net_device *vlan_find_dev(struct net_device *real_dev,
 					       u16 vlan_id)
 {
-	struct vlan_group *grp = rcu_dereference_rtnl(real_dev->vlgrp);
+	struct vlan_info *vlan_info = rcu_dereference_rtnl(real_dev->vlan_info);
 
-	if (grp)
-		return vlan_group_get_device(grp, vlan_id);
+	if (vlan_info)
+		return vlan_group_get_device(&vlan_info->grp, vlan_id);
 
 	return NULL;
 }