bridge: vlan: add per-vlan struct and move to rhashtables

This patch changes the bridge vlan implementation to use rhashtables
instead of bitmaps. The main motivation behind this change is that we
need extensible per-vlan structures (both per-port and global) so more
advanced features can be introduced and the vlan support can be
extended. I've tried to break this up but the moment net_port_vlans is
changed and the whole API goes away, thus this is a larger patch.
A few short goals of this patch are:
- Extensible per-vlan structs stored in rhashtables and a sorted list
- Keep user-visible behaviour (compressed vlans etc)
- Keep fastpath ingress/egress logic the same (optimizations to come
  later)

Here's a brief list of some of the new features we'd like to introduce:
- per-vlan counters
- vlan ingress/egress mapping
- per-vlan igmp configuration
- vlan priorities
- avoid fdb entries replication (e.g. local fdb scaling issues)

The structure is kept single for both global and per-port entries so to
avoid code duplication where possible and also because we'll soon introduce
"port0 / aka bridge as port" which should simplify things further
(thanks to Vlad for the suggestion!).

Now we have per-vlan global rhashtable (bridge-wide) and per-vlan port
rhashtable, if an entry is added to a port it'll get a pointer to its
global context so it can be quickly accessed later. There's also a
sorted vlan list which is used for stable walks and some user-visible
behaviour such as the vlan ranges, also for error paths.
VLANs are stored in a "vlan group" which currently contains the
rhashtable, sorted vlan list and the number of "real" vlan entries.
A good side-effect of this change is that it resembles how hw keeps
per-vlan data.
One important note after this change is that if a VLAN is being looked up
in the bridge's rhashtable for filtering purposes (or to check if it's an
existing usable entry, not just a global context) then the new helper
br_vlan_should_use() needs to be used if the vlan is found. In case the
lookup is done only with a port's vlan group, then this check can be
skipped.

Things tested so far:
- basic vlan ingress/egress
- pvids
- untagged vlans
- undef CONFIG_BRIDGE_VLAN_FILTERING
- adding/deleting vlans in different scenarios (with/without global ctx,
  while transmitting traffic, in ranges etc)
- loading/removing the module while having/adding/deleting vlans
- extracting bridge vlan information (user ABI), compressed requests
- adding/deleting fdbs on vlans
- bridge mac change, promisc mode
- default pvid change
- kmemleak ON during the whole time

Signed-off-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 98 insertions, 76 deletions

diff --git a/net/bridge/br_netlink.c b/net/bridge/br_netlink.c
index ea748c93a07f..bb8bb7b36f04 100644
--- a/net/bridge/br_netlink.c
+++ b/net/bridge/br_netlink.c
@@ -21,36 +21,35 @@
 #include "br_private.h"
 #include "br_private_stp.h"
 
-static int br_get_num_vlan_infos(const struct net_port_vlans *pv,
-				 u32 filter_mask)
+static int __get_num_vlan_infos(struct net_bridge_vlan_group *vg,
+				u32 filter_mask,
+				u16 pvid)
 {
-	u16 vid_range_start = 0, vid_range_end = 0;
-	u16 vid_range_flags = 0;
-	u16 pvid, vid, flags;
+	struct net_bridge_vlan *v;
+	u16 vid_range_start = 0, vid_range_end = 0, vid_range_flags = 0;
+	u16 flags;
 	int num_vlans = 0;
 
-	if (filter_mask & RTEXT_FILTER_BRVLAN)
-		return pv->num_vlans;
-
 	if (!(filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED))
 		return 0;
 
-	/* Count number of vlan info's
-	 */
-	pvid = br_get_pvid(pv);
-	for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID) {
+	/* Count number of vlan infos */
+	list_for_each_entry(v, &vg->vlan_list, vlist) {
 		flags = 0;
-		if (vid == pvid)
+		/* only a context, bridge vlan not activated */
+		if (!br_vlan_should_use(v))
+			continue;
+		if (v->vid == pvid)
 			flags |= BRIDGE_VLAN_INFO_PVID;
 
-		if (test_bit(vid, pv->untagged_bitmap))
+		if (v->flags & BRIDGE_VLAN_INFO_UNTAGGED)
 			flags |= BRIDGE_VLAN_INFO_UNTAGGED;
 
 		if (vid_range_start == 0) {
 			goto initvars;
-		} else if ((vid - vid_range_end) == 1 &&
+		} else if ((v->vid - vid_range_end) == 1 &&
 			flags == vid_range_flags) {
-			vid_range_end = vid;
+			vid_range_end = v->vid;
 			continue;
 		} else {
 			if ((vid_range_end - vid_range_start) > 0)
@@ -59,8 +58,8 @@ static int br_get_num_vlan_infos(const struct net_port_vlans *pv,
 				num_vlans += 1;
 		}
 initvars:
-		vid_range_start = vid;
-		vid_range_end = vid;
+		vid_range_start = v->vid;
+		vid_range_end = v->vid;
 		vid_range_flags = flags;
 	}
 
@@ -74,28 +73,40 @@ initvars:
 	return num_vlans;
 }
 
+static int br_get_num_vlan_infos(struct net_bridge_vlan_group *vg,
+				 u32 filter_mask, u16 pvid)
+{
+	if (!vg)
+		return 0;
+
+	if (filter_mask & RTEXT_FILTER_BRVLAN)
+		return vg->num_vlans;
+
+	return __get_num_vlan_infos(vg, filter_mask, pvid);
+}
+
 static size_t br_get_link_af_size_filtered(const struct net_device *dev,
 					   u32 filter_mask)
 {
-	struct net_port_vlans *pv;
+	struct net_bridge_vlan_group *vg = NULL;
+	struct net_bridge_port *p;
+	struct net_bridge *br;
 	int num_vlan_infos;
+	u16 pvid = 0;
 
 	rcu_read_lock();
-	if (br_port_exists(dev))
-		pv = nbp_get_vlan_info(br_port_get_rcu(dev));
-	else if (dev->priv_flags & IFF_EBRIDGE)
-		pv = br_get_vlan_info((struct net_bridge *)netdev_priv(dev));
-	else
-		pv = NULL;
-	if (pv)
-		num_vlan_infos = br_get_num_vlan_infos(pv, filter_mask);
-	else
-		num_vlan_infos = 0;
+	if (br_port_exists(dev)) {
+		p = br_port_get_rcu(dev);
+		vg = nbp_vlan_group(p);
+		pvid = nbp_get_pvid(p);
+	} else if (dev->priv_flags & IFF_EBRIDGE) {
+		br = netdev_priv(dev);
+		vg = br_vlan_group(br);
+		pvid = br_get_pvid(br);
+	}
+	num_vlan_infos = br_get_num_vlan_infos(vg, filter_mask, pvid);
 	rcu_read_unlock();
 
-	if (!num_vlan_infos)
-		return 0;
-
 	/* Each VLAN is returned in bridge_vlan_info along with flags */
 	return num_vlan_infos * nla_total_size(sizeof(struct bridge_vlan_info));
 }
@@ -185,31 +196,33 @@ nla_put_failure:
 }
 
 static int br_fill_ifvlaninfo_compressed(struct sk_buff *skb,
-					 const struct net_port_vlans *pv)
+					 struct net_bridge_vlan_group *vg,
+					 u16 pvid)
 {
-	u16 vid_range_start = 0, vid_range_end = 0;
-	u16 vid_range_flags = 0;
-	u16 pvid, vid, flags;
+	struct net_bridge_vlan *v;
+	u16 vid_range_start = 0, vid_range_end = 0, vid_range_flags = 0;
+	u16 flags;
 	int err = 0;
 
 	/* Pack IFLA_BRIDGE_VLAN_INFO's for every vlan
 	 * and mark vlan info with begin and end flags
 	 * if vlaninfo represents a range
 	 */
-	pvid = br_get_pvid(pv);
-	for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID) {
+	list_for_each_entry(v, &vg->vlan_list, vlist) {
 		flags = 0;
-		if (vid == pvid)
+		if (!br_vlan_should_use(v))
+			continue;
+		if (v->vid == pvid)
 			flags |= BRIDGE_VLAN_INFO_PVID;
 
-		if (test_bit(vid, pv->untagged_bitmap))
+		if (v->flags & BRIDGE_VLAN_INFO_UNTAGGED)
 			flags |= BRIDGE_VLAN_INFO_UNTAGGED;
 
 		if (vid_range_start == 0) {
 			goto initvars;
-		} else if ((vid - vid_range_end) == 1 &&
+		} else if ((v->vid - vid_range_end) == 1 &&
 			flags == vid_range_flags) {
-			vid_range_end = vid;
+			vid_range_end = v->vid;
 			continue;
 		} else {
 			err = br_fill_ifvlaninfo_range(skb, vid_range_start,
@@ -220,8 +233,8 @@ static int br_fill_ifvlaninfo_compressed(struct sk_buff *skb,
 		}
 
 initvars:
-		vid_range_start = vid;
-		vid_range_end = vid;
+		vid_range_start = v->vid;
+		vid_range_end = v->vid;
 		vid_range_flags = flags;
 	}
 
@@ -238,19 +251,22 @@ initvars:
 }
 
 static int br_fill_ifvlaninfo(struct sk_buff *skb,
-			      const struct net_port_vlans *pv)
+			      struct net_bridge_vlan_group *vg,
+			      u16 pvid)
 {
 	struct bridge_vlan_info vinfo;
-	u16 pvid, vid;
+	struct net_bridge_vlan *v;
 
-	pvid = br_get_pvid(pv);
-	for_each_set_bit(vid, pv->vlan_bitmap, VLAN_N_VID) {
-		vinfo.vid = vid;
+	list_for_each_entry(v, &vg->vlan_list, vlist) {
+		if (!br_vlan_should_use(v))
+			continue;
+
+		vinfo.vid = v->vid;
 		vinfo.flags = 0;
-		if (vid == pvid)
+		if (v->vid == pvid)
 			vinfo.flags |= BRIDGE_VLAN_INFO_PVID;
 
-		if (test_bit(vid, pv->untagged_bitmap))
+		if (v->flags & BRIDGE_VLAN_INFO_UNTAGGED)
 			vinfo.flags |= BRIDGE_VLAN_INFO_UNTAGGED;
 
 		if (nla_put(skb, IFLA_BRIDGE_VLAN_INFO,
@@ -269,11 +285,11 @@ nla_put_failure:
  * Contains port and master info as well as carrier and bridge state.
  */
 static int br_fill_ifinfo(struct sk_buff *skb,
-			  const struct net_bridge_port *port,
+			  struct net_bridge_port *port,
 			  u32 pid, u32 seq, int event, unsigned int flags,
 			  u32 filter_mask, const struct net_device *dev)
 {
-	const struct net_bridge *br;
+	struct net_bridge *br;
 	struct ifinfomsg *hdr;
 	struct nlmsghdr *nlh;
 	u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN;
@@ -320,16 +336,20 @@ static int br_fill_ifinfo(struct sk_buff *skb,
 	/* Check if  the VID information is requested */
 	if ((filter_mask & RTEXT_FILTER_BRVLAN) ||
 	    (filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED)) {
-		const struct net_port_vlans *pv;
+		struct net_bridge_vlan_group *vg;
 		struct nlattr *af;
+		u16 pvid;
 		int err;
 
-		if (port)
-			pv = nbp_get_vlan_info(port);
-		else
-			pv = br_get_vlan_info(br);
+		if (port) {
+			vg = nbp_vlan_group(port);
+			pvid = nbp_get_pvid(port);
+		} else {
+			vg = br_vlan_group(br);
+			pvid = br_get_pvid(br);
+		}
 
-		if (!pv || bitmap_empty(pv->vlan_bitmap, VLAN_N_VID))
+		if (!vg || !vg->num_vlans)
 			goto done;
 
 		af = nla_nest_start(skb, IFLA_AF_SPEC);
@@ -337,9 +357,9 @@ static int br_fill_ifinfo(struct sk_buff *skb,
 			goto nla_put_failure;
 
 		if (filter_mask & RTEXT_FILTER_BRVLAN_COMPRESSED)
-			err = br_fill_ifvlaninfo_compressed(skb, pv);
+			err = br_fill_ifvlaninfo_compressed(skb, vg, pvid);
 		else
-			err = br_fill_ifvlaninfo(skb, pv);
+			err = br_fill_ifvlaninfo(skb, vg, pvid);
 		if (err)
 			goto nla_put_failure;
 		nla_nest_end(skb, af);
@@ -413,14 +433,14 @@ static int br_vlan_info(struct net_bridge *br, struct net_bridge_port *p,
 	switch (cmd) {
 	case RTM_SETLINK:
 		if (p) {
+			/* if the MASTER flag is set this will act on the global
+			 * per-VLAN entry as well
+			 */
 			err = nbp_vlan_add(p, vinfo->vid, vinfo->flags);
 			if (err)
 				break;
-
-			if (vinfo->flags & BRIDGE_VLAN_INFO_MASTER)
-				err = br_vlan_add(p->br, vinfo->vid,
-						  vinfo->flags);
 		} else {
+			vinfo->flags |= BRIDGE_VLAN_INFO_BRENTRY;
 			err = br_vlan_add(br, vinfo->vid, vinfo->flags);
 		}
 		break;
@@ -857,20 +877,22 @@ static int br_fill_info(struct sk_buff *skb, const struct net_device *brdev)
 
 static size_t br_get_link_af_size(const struct net_device *dev)
 {
-	struct net_port_vlans *pv;
-
-	if (br_port_exists(dev))
-		pv = nbp_get_vlan_info(br_port_get_rtnl(dev));
-	else if (dev->priv_flags & IFF_EBRIDGE)
-		pv = br_get_vlan_info((struct net_bridge *)netdev_priv(dev));
-	else
-		return 0;
+	struct net_bridge_port *p;
+	struct net_bridge *br;
+	int num_vlans = 0;
 
-	if (!pv)
-		return 0;
+	if (br_port_exists(dev)) {
+		p = br_port_get_rtnl(dev);
+		num_vlans = br_get_num_vlan_infos(nbp_vlan_group(p),
+						  RTEXT_FILTER_BRVLAN, 0);
+	} else if (dev->priv_flags & IFF_EBRIDGE) {
+		br = netdev_priv(dev);
+		num_vlans = br_get_num_vlan_infos(br_vlan_group(br),
+						  RTEXT_FILTER_BRVLAN, 0);
+	}
 
 	/* Each VLAN is returned in bridge_vlan_info along with flags */
-	return pv->num_vlans * nla_total_size(sizeof(struct bridge_vlan_info));
+	return num_vlans * nla_total_size(sizeof(struct bridge_vlan_info));
 }
 
 static struct rtnl_af_ops br_af_ops __read_mostly = {