WSL2-Linux-Kernel/net/bridge/br_vlan.c

#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/rtnetlink.h>
#include <linux/slab.h>
#include <net/switchdev.h>

#include "br_private.h"

static inline int br_vlan_cmp(struct rhashtable_compare_arg *arg,
			      const void *ptr)
{
	const struct net_bridge_vlan *vle = ptr;
	u16 vid = *(u16 *)arg->key;

	return vle->vid != vid;
}

static const struct rhashtable_params br_vlan_rht_params = {
	.head_offset = offsetof(struct net_bridge_vlan, vnode),
	.key_offset = offsetof(struct net_bridge_vlan, vid),
	.key_len = sizeof(u16),
	.nelem_hint = 3,
	.locks_mul = 1,
	.max_size = VLAN_N_VID,
	.obj_cmpfn = br_vlan_cmp,
	.automatic_shrinking = true,
};

static struct net_bridge_vlan *br_vlan_lookup(struct rhashtable *tbl, u16 vid)
{
	return rhashtable_lookup_fast(tbl, &vid, br_vlan_rht_params);
}

static void __vlan_add_pvid(u16 *pvid, u16 vid)
{
	if (*pvid == vid)
		return;

	smp_wmb();
	*pvid = vid;
}

static void __vlan_delete_pvid(u16 *pvid, u16 vid)
{
	if (*pvid != vid)
		return;

	smp_wmb();
	*pvid = 0;
}

static void __vlan_add_flags(struct net_bridge_vlan *v, u16 flags)
{
	if (flags & BRIDGE_VLAN_INFO_PVID) {
		if (br_vlan_is_master(v))
			__vlan_add_pvid(&v->br->pvid, v->vid);
		else
			__vlan_add_pvid(&v->port->pvid, v->vid);
	} else {
		if (br_vlan_is_master(v))
			__vlan_delete_pvid(&v->br->pvid, v->vid);
		else
			__vlan_delete_pvid(&v->port->pvid, v->vid);
	}

	if (flags & BRIDGE_VLAN_INFO_UNTAGGED)
		v->flags |= BRIDGE_VLAN_INFO_UNTAGGED;
	else
		v->flags &= ~BRIDGE_VLAN_INFO_UNTAGGED;
}

static int __vlan_vid_add(struct net_device *dev, struct net_bridge *br,
			  u16 vid, u16 flags)
{
	const struct net_device_ops *ops = dev->netdev_ops;
	int err;

	/* If driver uses VLAN ndo ops, use 8021q to install vid
	 * on device, otherwise try switchdev ops to install vid.
	 */

	if (ops->ndo_vlan_rx_add_vid) {
		err = vlan_vid_add(dev, br->vlan_proto, vid);
	} else {
		struct switchdev_obj_vlan v = {
			.flags = flags,
			.vid_begin = vid,
			.vid_end = vid,
		};

		err = switchdev_port_obj_add(dev, SWITCHDEV_OBJ_PORT_VLAN, &v);
		if (err == -EOPNOTSUPP)
			err = 0;
	}

	return err;
}

static void __vlan_add_list(struct net_bridge_vlan *v)
{
	struct list_head *headp, *hpos;
	struct net_bridge_vlan *vent;

	headp = br_vlan_is_master(v) ? &v->br->vlgrp->vlan_list :
				       &v->port->vlgrp->vlan_list;
	list_for_each_prev(hpos, headp) {
		vent = list_entry(hpos, struct net_bridge_vlan, vlist);
		if (v->vid < vent->vid)
			continue;
		else
			break;
	}
	list_add(&v->vlist, hpos);
}

static void __vlan_del_list(struct net_bridge_vlan *v)
{
	list_del(&v->vlist);
}

static int __vlan_vid_del(struct net_device *dev, struct net_bridge *br,
			  u16 vid)
{
	const struct net_device_ops *ops = dev->netdev_ops;
	int err = 0;

	/* If driver uses VLAN ndo ops, use 8021q to delete vid
	 * on device, otherwise try switchdev ops to delete vid.
	 */

	if (ops->ndo_vlan_rx_kill_vid) {
		vlan_vid_del(dev, br->vlan_proto, vid);
	} else {
		struct switchdev_obj_vlan v = {
			.vid_begin = vid,
			.vid_end = vid,
		};

		err = switchdev_port_obj_del(dev, SWITCHDEV_OBJ_PORT_VLAN, &v);
		if (err == -EOPNOTSUPP)
			err = 0;
	}

	return err;
}

/* This is the shared VLAN add function which works for both ports and bridge
 * devices. There are four possible calls to this function in terms of the
 * vlan entry type:
 * 1. vlan is being added on a port (no master flags, global entry exists)
 * 2. vlan is being added on a bridge (both master and brvlan flags)
 * 3. vlan is being added on a port, but a global entry didn't exist which
 *    is being created right now (master flag set, brvlan flag unset), the
 *    global entry is used for global per-vlan features, but not for filtering
 * 4. same as 3 but with both master and brvlan flags set so the entry
 *    will be used for filtering in both the port and the bridge
 */
static int __vlan_add(struct net_bridge_vlan *v, u16 flags)
{
	struct net_bridge_vlan *masterv = NULL;
	struct net_bridge_port *p = NULL;
	struct rhashtable *tbl;
	struct net_device *dev;
	struct net_bridge *br;
	int err;

	if (br_vlan_is_master(v)) {
		br = v->br;
		dev = br->dev;
		tbl = &br->vlgrp->vlan_hash;
	} else {
		p = v->port;
		br = p->br;
		dev = p->dev;
		tbl = &p->vlgrp->vlan_hash;
	}

	if (p) {
		u16 master_flags = flags;

		/* Add VLAN to the device filter if it is supported.
		 * This ensures tagged traffic enters the bridge when
		 * promiscuous mode is disabled by br_manage_promisc().
		 */
		err = __vlan_vid_add(dev, br, v->vid, flags);
		if (err)
			goto out;

		/* need to work on the master vlan too */
		if (flags & BRIDGE_VLAN_INFO_MASTER) {
			master_flags |= BRIDGE_VLAN_INFO_BRENTRY;
			err = br_vlan_add(br, v->vid, master_flags);
			if (err)
				goto out_filt;
		}

		masterv = br_vlan_find(br->vlgrp, v->vid);
		if (!masterv) {
			/* missing global ctx, create it now */
			err = br_vlan_add(br, v->vid, master_flags);
			if (err)
				goto out_filt;
			masterv = br_vlan_find(br->vlgrp, v->vid);
			WARN_ON(!masterv);
		}
		atomic_inc(&masterv->refcnt);
		v->brvlan = masterv;
	}

	/* Add the dev mac only if it's a usable vlan */
	if (br_vlan_should_use(v)) {
		err = br_fdb_insert(br, p, dev->dev_addr, v->vid);
		if (err) {
			br_err(br, "failed insert local address into bridge forwarding table\n");
			goto out_filt;
		}
	}

	err = rhashtable_lookup_insert_fast(tbl, &v->vnode, br_vlan_rht_params);
	if (err)
		goto out_fdb_insert;

	__vlan_add_list(v);
	__vlan_add_flags(v, flags);
	if (br_vlan_is_master(v)) {
		if (br_vlan_is_brentry(v))
			br->vlgrp->num_vlans++;
	} else {
		p->vlgrp->num_vlans++;
	}
out:
	return err;

out_fdb_insert:
	br_fdb_find_delete_local(br, p, br->dev->dev_addr, v->vid);

out_filt:
	if (p) {
		__vlan_vid_del(dev, br, v->vid);
		if (masterv) {
			atomic_dec(&masterv->refcnt);
			v->brvlan = NULL;
		}
	}

	goto out;
}

static int __vlan_del(struct net_bridge_vlan *v)
{
	struct net_bridge_vlan *masterv = v;
	struct net_bridge_port *p = NULL;
	struct net_bridge *br;
	int err = 0;
	struct rhashtable *tbl;
	u16 *pvid;

	if (br_vlan_is_master(v)) {
		br = v->br;
		tbl = &v->br->vlgrp->vlan_hash;
		pvid = &v->br->pvid;
	} else {
		p = v->port;
		br = p->br;
		tbl = &p->vlgrp->vlan_hash;
		masterv = v->brvlan;
		pvid = &p->pvid;
	}

	__vlan_delete_pvid(pvid, v->vid);
	if (p) {
		err = __vlan_vid_del(p->dev, p->br, v->vid);
		if (err)
			goto out;
	}

	if (br_vlan_is_master(v)) {
		if (br_vlan_is_brentry(v)) {
			v->flags &= ~BRIDGE_VLAN_INFO_BRENTRY;
			br->vlgrp->num_vlans--;
		}
	} else {
		p->vlgrp->num_vlans--;
	}

	if (masterv != v) {
		rhashtable_remove_fast(tbl, &v->vnode, br_vlan_rht_params);
		__vlan_del_list(v);
		kfree_rcu(v, rcu);
	}

	if (atomic_dec_and_test(&masterv->refcnt)) {
		rhashtable_remove_fast(&masterv->br->vlgrp->vlan_hash,
				       &masterv->vnode, br_vlan_rht_params);
		__vlan_del_list(masterv);
		kfree_rcu(masterv, rcu);
	}
out:
	return err;
}

static void __vlan_flush(struct net_bridge_vlan_group *vlgrp, u16 *pvid)
{
	struct net_bridge_vlan *vlan, *tmp;

	__vlan_delete_pvid(pvid, *pvid);
	list_for_each_entry_safe(vlan, tmp, &vlgrp->vlan_list, vlist)
		__vlan_del(vlan);
	rhashtable_destroy(&vlgrp->vlan_hash);
	kfree(vlgrp);
}

struct sk_buff *br_handle_vlan(struct net_bridge *br,
			       struct net_bridge_vlan_group *vg,
			       struct sk_buff *skb)
{
	struct net_bridge_vlan *v;
	u16 vid;

	/* If this packet was not filtered at input, let it pass */
	if (!BR_INPUT_SKB_CB(skb)->vlan_filtered)
		goto out;

	/* At this point, we know that the frame was filtered and contains
	 * a valid vlan id.  If the vlan id has untagged flag set,
	 * send untagged; otherwise, send tagged.
	 */
	br_vlan_get_tag(skb, &vid);
	v = br_vlan_find(vg, vid);
	/* Vlan entry must be configured at this point.  The
	 * only exception is the bridge is set in promisc mode and the
	 * packet is destined for the bridge device.  In this case
	 * pass the packet as is.
	 */
	if (!v || !br_vlan_should_use(v)) {
		if ((br->dev->flags & IFF_PROMISC) && skb->dev == br->dev) {
			goto out;
		} else {
			kfree_skb(skb);
			return NULL;
		}
	}
	if (v->flags & BRIDGE_VLAN_INFO_UNTAGGED)
		skb->vlan_tci = 0;

out:
	return skb;
}

/* Called under RCU */
static bool __allowed_ingress(struct rhashtable *tbl, u16 pvid, __be16 proto,
			      struct sk_buff *skb, u16 *vid)
{
	const struct net_bridge_vlan *v;
	bool tagged;

	BR_INPUT_SKB_CB(skb)->vlan_filtered = true;
	/* If vlan tx offload is disabled on bridge device and frame was
	 * sent from vlan device on the bridge device, it does not have
	 * HW accelerated vlan tag.
	 */
	if (unlikely(!skb_vlan_tag_present(skb) &&
		     skb->protocol == proto)) {
		skb = skb_vlan_untag(skb);
		if (unlikely(!skb))
			return false;
	}

	if (!br_vlan_get_tag(skb, vid)) {
		/* Tagged frame */
		if (skb->vlan_proto != proto) {
			/* Protocol-mismatch, empty out vlan_tci for new tag */
			skb_push(skb, ETH_HLEN);
			skb = vlan_insert_tag_set_proto(skb, skb->vlan_proto,
							skb_vlan_tag_get(skb));
			if (unlikely(!skb))
				return false;

			skb_pull(skb, ETH_HLEN);
			skb_reset_mac_len(skb);
			*vid = 0;
			tagged = false;
		} else {
			tagged = true;
		}
	} else {
		/* Untagged frame */
		tagged = false;
	}

	if (!*vid) {
		/* Frame had a tag with VID 0 or did not have a tag.
		 * See if pvid is set on this port.  That tells us which
		 * vlan untagged or priority-tagged traffic belongs to.
		 */
		if (!pvid)
			goto drop;

		/* PVID is set on this port.  Any untagged or priority-tagged
		 * ingress frame is considered to belong to this vlan.
		 */
		*vid = pvid;
		if (likely(!tagged))
			/* Untagged Frame. */
			__vlan_hwaccel_put_tag(skb, proto, pvid);
		else
			/* Priority-tagged Frame.
			 * At this point, We know that skb->vlan_tci had
			 * VLAN_TAG_PRESENT bit and its VID field was 0x000.
			 * We update only VID field and preserve PCP field.
			 */
			skb->vlan_tci |= pvid;

		return true;
	}

	/* Frame had a valid vlan tag.  See if vlan is allowed */
	v = br_vlan_lookup(tbl, *vid);
	if (v && br_vlan_should_use(v))
		return true;
drop:
	kfree_skb(skb);
	return false;
}

bool br_allowed_ingress(struct net_bridge *br, struct sk_buff *skb, u16 *vid)
{
	/* If VLAN filtering is disabled on the bridge, all packets are
	 * permitted.
	 */
	if (!br->vlan_enabled) {
		BR_INPUT_SKB_CB(skb)->vlan_filtered = false;
		return true;
	}

	return __allowed_ingress(&br->vlgrp->vlan_hash, br->pvid,
				 br->vlan_proto, skb, vid);
}

bool nbp_allowed_ingress(struct net_bridge_port *p, struct sk_buff *skb,
			 u16 *vid)
{
	struct net_bridge *br = p->br;

	/* If VLAN filtering is disabled on the bridge, all packets are
	 * permitted.
	 */
	if (!br->vlan_enabled) {
		BR_INPUT_SKB_CB(skb)->vlan_filtered = false;
		return true;
	}

	return __allowed_ingress(&p->vlgrp->vlan_hash, p->pvid, br->vlan_proto,
				 skb, vid);
}

/* Called under RCU. */
bool br_allowed_egress(struct net_bridge_vlan_group *vg,
		       const struct sk_buff *skb)
{
	const struct net_bridge_vlan *v;
	u16 vid;

	/* If this packet was not filtered at input, let it pass */
	if (!BR_INPUT_SKB_CB(skb)->vlan_filtered)
		return true;

	br_vlan_get_tag(skb, &vid);
	v = br_vlan_find(vg, vid);
	if (v && br_vlan_should_use(v))
		return true;

	return false;
}

/* Called under RCU */
bool br_should_learn(struct net_bridge_port *p, struct sk_buff *skb, u16 *vid)
{
	struct net_bridge *br = p->br;

	/* If filtering was disabled at input, let it pass. */
	if (!br->vlan_enabled)
		return true;

	if (!p->vlgrp->num_vlans)
		return false;

	if (!br_vlan_get_tag(skb, vid) && skb->vlan_proto != br->vlan_proto)
		*vid = 0;

	if (!*vid) {
		*vid = nbp_get_pvid(p);
		if (!*vid)
			return false;

		return true;
	}

	if (br_vlan_find(p->vlgrp, *vid))
		return true;

	return false;
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int br_vlan_add(struct net_bridge *br, u16 vid, u16 flags)
{
	struct net_bridge_vlan *vlan;
	int ret;

	ASSERT_RTNL();

	vlan = br_vlan_find(br->vlgrp, vid);
	if (vlan) {
		if (!br_vlan_is_brentry(vlan)) {
			/* Trying to change flags of non-existent bridge vlan */
			if (!(flags & BRIDGE_VLAN_INFO_BRENTRY))
				return -EINVAL;
			/* It was only kept for port vlans, now make it real */
			ret = br_fdb_insert(br, NULL, br->dev->dev_addr,
					    vlan->vid);
			if (ret) {
				br_err(br, "failed insert local address into bridge forwarding table\n");
				return ret;
			}
			atomic_inc(&vlan->refcnt);
			vlan->flags |= BRIDGE_VLAN_INFO_BRENTRY;
			br->vlgrp->num_vlans++;
		}
		__vlan_add_flags(vlan, flags);
		return 0;
	}

	vlan = kzalloc(sizeof(*vlan), GFP_KERNEL);
	if (!vlan)
		return -ENOMEM;

	vlan->vid = vid;
	vlan->flags = flags | BRIDGE_VLAN_INFO_MASTER;
	vlan->flags &= ~BRIDGE_VLAN_INFO_PVID;
	vlan->br = br;
	if (flags & BRIDGE_VLAN_INFO_BRENTRY)
		atomic_set(&vlan->refcnt, 1);
	ret = __vlan_add(vlan, flags);
	if (ret)
		kfree(vlan);

	return ret;
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int br_vlan_delete(struct net_bridge *br, u16 vid)
{
	struct net_bridge_vlan *v;

	ASSERT_RTNL();

	v = br_vlan_find(br->vlgrp, vid);
	if (!v || !br_vlan_is_brentry(v))
		return -ENOENT;

	br_fdb_find_delete_local(br, NULL, br->dev->dev_addr, vid);

	return __vlan_del(v);
}

void br_vlan_flush(struct net_bridge *br)
{
	ASSERT_RTNL();

	__vlan_flush(br_vlan_group(br), &br->pvid);
}

struct net_bridge_vlan *br_vlan_find(struct net_bridge_vlan_group *vg, u16 vid)
{
	if (!vg)
		return NULL;

	return br_vlan_lookup(&vg->vlan_hash, vid);
}

/* Must be protected by RTNL. */
static void recalculate_group_addr(struct net_bridge *br)
{
	if (br->group_addr_set)
		return;

	spin_lock_bh(&br->lock);
	if (!br->vlan_enabled || br->vlan_proto == htons(ETH_P_8021Q)) {
		/* Bridge Group Address */
		br->group_addr[5] = 0x00;
	} else { /* vlan_enabled && ETH_P_8021AD */
		/* Provider Bridge Group Address */
		br->group_addr[5] = 0x08;
	}
	spin_unlock_bh(&br->lock);
}

/* Must be protected by RTNL. */
void br_recalculate_fwd_mask(struct net_bridge *br)
{
	if (!br->vlan_enabled || br->vlan_proto == htons(ETH_P_8021Q))
		br->group_fwd_mask_required = BR_GROUPFWD_DEFAULT;
	else /* vlan_enabled && ETH_P_8021AD */
		br->group_fwd_mask_required = BR_GROUPFWD_8021AD &
					      ~(1u << br->group_addr[5]);
}

int __br_vlan_filter_toggle(struct net_bridge *br, unsigned long val)
{
	if (br->vlan_enabled == val)
		return 0;

	br->vlan_enabled = val;
	br_manage_promisc(br);
	recalculate_group_addr(br);
	br_recalculate_fwd_mask(br);

	return 0;
}

int br_vlan_filter_toggle(struct net_bridge *br, unsigned long val)
{
	if (!rtnl_trylock())
		return restart_syscall();

	__br_vlan_filter_toggle(br, val);
	rtnl_unlock();

	return 0;
}

int __br_vlan_set_proto(struct net_bridge *br, __be16 proto)
{
	int err = 0;
	struct net_bridge_port *p;
	struct net_bridge_vlan *vlan;
	__be16 oldproto;

	if (br->vlan_proto == proto)
		return 0;

	/* Add VLANs for the new proto to the device filter. */
	list_for_each_entry(p, &br->port_list, list) {
		list_for_each_entry(vlan, &p->vlgrp->vlan_list, vlist) {
			err = vlan_vid_add(p->dev, proto, vlan->vid);
			if (err)
				goto err_filt;
		}
	}

	oldproto = br->vlan_proto;
	br->vlan_proto = proto;

	recalculate_group_addr(br);
	br_recalculate_fwd_mask(br);

	/* Delete VLANs for the old proto from the device filter. */
	list_for_each_entry(p, &br->port_list, list)
		list_for_each_entry(vlan, &p->vlgrp->vlan_list, vlist)
			vlan_vid_del(p->dev, oldproto, vlan->vid);

	return 0;

err_filt:
	list_for_each_entry_continue_reverse(vlan, &p->vlgrp->vlan_list, vlist)
		vlan_vid_del(p->dev, proto, vlan->vid);

	list_for_each_entry_continue_reverse(p, &br->port_list, list)
		list_for_each_entry(vlan, &p->vlgrp->vlan_list, vlist)
			vlan_vid_del(p->dev, proto, vlan->vid);

	return err;
}

int br_vlan_set_proto(struct net_bridge *br, unsigned long val)
{
	int err;

	if (val != ETH_P_8021Q && val != ETH_P_8021AD)
		return -EPROTONOSUPPORT;

	if (!rtnl_trylock())
		return restart_syscall();

	err = __br_vlan_set_proto(br, htons(val));
	rtnl_unlock();

	return err;
}

static bool vlan_default_pvid(struct net_bridge_vlan_group *vg, u16 pvid,
			      u16 vid)
{
	struct net_bridge_vlan *v;

	if (vid != pvid)
		return false;

	v = br_vlan_lookup(&vg->vlan_hash, vid);
	if (v && br_vlan_should_use(v) &&
	    (v->flags & BRIDGE_VLAN_INFO_UNTAGGED))
		return true;

	return false;
}

static void br_vlan_disable_default_pvid(struct net_bridge *br)
{
	struct net_bridge_port *p;
	u16 pvid = br->default_pvid;

	/* Disable default_pvid on all ports where it is still
	 * configured.
	 */
	if (vlan_default_pvid(br->vlgrp, br->pvid, pvid))
		br_vlan_delete(br, pvid);

	list_for_each_entry(p, &br->port_list, list) {
		if (vlan_default_pvid(p->vlgrp, p->pvid, pvid))
			nbp_vlan_delete(p, pvid);
	}

	br->default_pvid = 0;
}

static int __br_vlan_set_default_pvid(struct net_bridge *br, u16 pvid)
{
	const struct net_bridge_vlan *pvent;
	struct net_bridge_port *p;
	u16 old_pvid;
	int err = 0;
	unsigned long *changed;

	changed = kcalloc(BITS_TO_LONGS(BR_MAX_PORTS), sizeof(unsigned long),
			  GFP_KERNEL);
	if (!changed)
		return -ENOMEM;

	old_pvid = br->default_pvid;

	/* Update default_pvid config only if we do not conflict with
	 * user configuration.
	 */
	pvent = br_vlan_find(br->vlgrp, pvid);
	if ((!old_pvid || vlan_default_pvid(br->vlgrp, br->pvid, old_pvid)) &&
	    (!pvent || !br_vlan_should_use(pvent))) {
		err = br_vlan_add(br, pvid,
				  BRIDGE_VLAN_INFO_PVID |
				  BRIDGE_VLAN_INFO_UNTAGGED |
				  BRIDGE_VLAN_INFO_BRENTRY);
		if (err)
			goto out;
		br_vlan_delete(br, old_pvid);
		set_bit(0, changed);
	}

	list_for_each_entry(p, &br->port_list, list) {
		/* Update default_pvid config only if we do not conflict with
		 * user configuration.
		 */
		if ((old_pvid &&
		     !vlan_default_pvid(p->vlgrp, p->pvid, old_pvid)) ||
		    br_vlan_find(p->vlgrp, pvid))
			continue;

		err = nbp_vlan_add(p, pvid,
				   BRIDGE_VLAN_INFO_PVID |
				   BRIDGE_VLAN_INFO_UNTAGGED);
		if (err)
			goto err_port;
		nbp_vlan_delete(p, old_pvid);
		set_bit(p->port_no, changed);
	}

	br->default_pvid = pvid;

out:
	kfree(changed);
	return err;

err_port:
	list_for_each_entry_continue_reverse(p, &br->port_list, list) {
		if (!test_bit(p->port_no, changed))
			continue;

		if (old_pvid)
			nbp_vlan_add(p, old_pvid,
				     BRIDGE_VLAN_INFO_PVID |
				     BRIDGE_VLAN_INFO_UNTAGGED);
		nbp_vlan_delete(p, pvid);
	}

	if (test_bit(0, changed)) {
		if (old_pvid)
			br_vlan_add(br, old_pvid,
				    BRIDGE_VLAN_INFO_PVID |
				    BRIDGE_VLAN_INFO_UNTAGGED |
				    BRIDGE_VLAN_INFO_BRENTRY);
		br_vlan_delete(br, pvid);
	}
	goto out;
}

int br_vlan_set_default_pvid(struct net_bridge *br, unsigned long val)
{
	u16 pvid = val;
	int err = 0;

	if (val >= VLAN_VID_MASK)
		return -EINVAL;

	if (!rtnl_trylock())
		return restart_syscall();

	if (pvid == br->default_pvid)
		goto unlock;

	/* Only allow default pvid change when filtering is disabled */
	if (br->vlan_enabled) {
		pr_info_once("Please disable vlan filtering to change default_pvid\n");
		err = -EPERM;
		goto unlock;
	}

	if (!pvid)
		br_vlan_disable_default_pvid(br);
	else
		err = __br_vlan_set_default_pvid(br, pvid);

unlock:
	rtnl_unlock();
	return err;
}

int br_vlan_init(struct net_bridge *br)
{
	int ret = -ENOMEM;

	br->vlgrp = kzalloc(sizeof(struct net_bridge_vlan_group), GFP_KERNEL);
	if (!br->vlgrp)
		goto out;
	ret = rhashtable_init(&br->vlgrp->vlan_hash, &br_vlan_rht_params);
	if (ret)
		goto err_rhtbl;
	INIT_LIST_HEAD(&br->vlgrp->vlan_list);
	br->vlan_proto = htons(ETH_P_8021Q);
	br->default_pvid = 1;
	ret = br_vlan_add(br, 1,
			  BRIDGE_VLAN_INFO_PVID | BRIDGE_VLAN_INFO_UNTAGGED |
			  BRIDGE_VLAN_INFO_BRENTRY);
	if (ret)
		goto err_vlan_add;

out:
	return ret;

err_vlan_add:
	rhashtable_destroy(&br->vlgrp->vlan_hash);
err_rhtbl:
	kfree(br->vlgrp);

	goto out;
}

int nbp_vlan_init(struct net_bridge_port *p)
{
	int ret = -ENOMEM;

	p->vlgrp = kzalloc(sizeof(struct net_bridge_vlan_group), GFP_KERNEL);
	if (!p->vlgrp)
		goto out;

	ret = rhashtable_init(&p->vlgrp->vlan_hash, &br_vlan_rht_params);
	if (ret)
		goto err_rhtbl;
	INIT_LIST_HEAD(&p->vlgrp->vlan_list);
	if (p->br->default_pvid) {
		ret = nbp_vlan_add(p, p->br->default_pvid,
				   BRIDGE_VLAN_INFO_PVID |
				   BRIDGE_VLAN_INFO_UNTAGGED);
		if (ret)
			goto err_vlan_add;
	}
out:
	return ret;

err_vlan_add:
	rhashtable_destroy(&p->vlgrp->vlan_hash);
err_rhtbl:
	kfree(p->vlgrp);

	goto out;
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags)
{
	struct net_bridge_vlan *vlan;
	int ret;

	ASSERT_RTNL();

	vlan = br_vlan_find(port->vlgrp, vid);
	if (vlan) {
		__vlan_add_flags(vlan, flags);
		return 0;
	}

	vlan = kzalloc(sizeof(*vlan), GFP_KERNEL);
	if (!vlan)
		return -ENOMEM;

	vlan->vid = vid;
	vlan->port = port;
	ret = __vlan_add(vlan, flags);
	if (ret)
		kfree(vlan);

	return ret;
}

/* Must be protected by RTNL.
 * Must be called with vid in range from 1 to 4094 inclusive.
 */
int nbp_vlan_delete(struct net_bridge_port *port, u16 vid)
{
	struct net_bridge_vlan *v;

	ASSERT_RTNL();

	v = br_vlan_find(port->vlgrp, vid);
	if (!v)
		return -ENOENT;
	br_fdb_find_delete_local(port->br, port, port->dev->dev_addr, vid);
	br_fdb_delete_by_port(port->br, port, vid, 0);

	return __vlan_del(v);
}

void nbp_vlan_flush(struct net_bridge_port *port)
{
	struct net_bridge_vlan *vlan;

	ASSERT_RTNL();

	list_for_each_entry(vlan, &port->vlgrp->vlan_list, vlist)
		vlan_vid_del(port->dev, port->br->vlan_proto, vlan->vid);

	__vlan_flush(nbp_vlan_group(port), &port->pvid);
}