Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1479 insertions, 0 deletions

diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
new file mode 100644
index 000000000..3162f955f
--- /dev/null
+++ b/net/mac80211/mesh.c
@@ -0,0 +1,1479 @@
+/*
+ * Copyright (c) 2008, 2009 open80211s Ltd.
+ * Authors:    Luis Carlos Cobo <luisca@cozybit.com>
+ * 	       Javier Cardona <javier@cozybit.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/slab.h>
+#include <asm/unaligned.h>
+#include "ieee80211_i.h"
+#include "mesh.h"
+#include "driver-ops.h"
+
+static int mesh_allocated;
+static struct kmem_cache *rm_cache;
+
+bool mesh_action_is_path_sel(struct ieee80211_mgmt *mgmt)
+{
+	return (mgmt->u.action.u.mesh_action.action_code ==
+			WLAN_MESH_ACTION_HWMP_PATH_SELECTION);
+}
+
+void ieee80211s_init(void)
+{
+	mesh_allocated = 1;
+	rm_cache = kmem_cache_create("mesh_rmc", sizeof(struct rmc_entry),
+				     0, 0, NULL);
+}
+
+void ieee80211s_stop(void)
+{
+	if (!mesh_allocated)
+		return;
+	kmem_cache_destroy(rm_cache);
+}
+
+static void ieee80211_mesh_housekeeping_timer(struct timer_list *t)
+{
+	struct ieee80211_sub_if_data *sdata =
+		from_timer(sdata, t, u.mesh.housekeeping_timer);
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+
+	set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
+
+	ieee80211_queue_work(&local->hw, &sdata->work);
+}
+
+/**
+ * mesh_matches_local - check if the config of a mesh point matches ours
+ *
+ * @sdata: local mesh subif
+ * @ie: information elements of a management frame from the mesh peer
+ *
+ * This function checks if the mesh configuration of a mesh point matches the
+ * local mesh configuration, i.e. if both nodes belong to the same mesh network.
+ */
+bool mesh_matches_local(struct ieee80211_sub_if_data *sdata,
+			struct ieee802_11_elems *ie)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	u32 basic_rates = 0;
+	struct cfg80211_chan_def sta_chan_def;
+	struct ieee80211_supported_band *sband;
+
+	/*
+	 * As support for each feature is added, check for matching
+	 * - On mesh config capabilities
+	 *   - Power Save Support En
+	 *   - Sync support enabled
+	 *   - Sync support active
+	 *   - Sync support required from peer
+	 *   - MDA enabled
+	 * - Power management control on fc
+	 */
+	if (!(ifmsh->mesh_id_len == ie->mesh_id_len &&
+	     memcmp(ifmsh->mesh_id, ie->mesh_id, ie->mesh_id_len) == 0 &&
+	     (ifmsh->mesh_pp_id == ie->mesh_config->meshconf_psel) &&
+	     (ifmsh->mesh_pm_id == ie->mesh_config->meshconf_pmetric) &&
+	     (ifmsh->mesh_cc_id == ie->mesh_config->meshconf_congest) &&
+	     (ifmsh->mesh_sp_id == ie->mesh_config->meshconf_synch) &&
+	     (ifmsh->mesh_auth_id == ie->mesh_config->meshconf_auth)))
+		return false;
+
+	sband = ieee80211_get_sband(sdata);
+	if (!sband)
+		return false;
+
+	ieee80211_sta_get_rates(sdata, ie, sband->band,
+				&basic_rates);
+
+	if (sdata->vif.bss_conf.basic_rates != basic_rates)
+		return false;
+
+	cfg80211_chandef_create(&sta_chan_def, sdata->vif.bss_conf.chandef.chan,
+				NL80211_CHAN_NO_HT);
+	ieee80211_chandef_ht_oper(ie->ht_operation, &sta_chan_def);
+	ieee80211_chandef_vht_oper(ie->vht_operation, &sta_chan_def);
+
+	if (!cfg80211_chandef_compatible(&sdata->vif.bss_conf.chandef,
+					 &sta_chan_def))
+		return false;
+
+	return true;
+}
+
+/**
+ * mesh_peer_accepts_plinks - check if an mp is willing to establish peer links
+ *
+ * @ie: information elements of a management frame from the mesh peer
+ */
+bool mesh_peer_accepts_plinks(struct ieee802_11_elems *ie)
+{
+	return (ie->mesh_config->meshconf_cap &
+			IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS) != 0;
+}
+
+/**
+ * mesh_accept_plinks_update - update accepting_plink in local mesh beacons
+ *
+ * @sdata: mesh interface in which mesh beacons are going to be updated
+ *
+ * Returns: beacon changed flag if the beacon content changed.
+ */
+u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata)
+{
+	bool free_plinks;
+	u32 changed = 0;
+
+	/* In case mesh_plink_free_count > 0 and mesh_plinktbl_capacity == 0,
+	 * the mesh interface might be able to establish plinks with peers that
+	 * are already on the table but are not on PLINK_ESTAB state. However,
+	 * in general the mesh interface is not accepting peer link requests
+	 * from new peers, and that must be reflected in the beacon
+	 */
+	free_plinks = mesh_plink_availables(sdata);
+
+	if (free_plinks != sdata->u.mesh.accepting_plinks) {
+		sdata->u.mesh.accepting_plinks = free_plinks;
+		changed = BSS_CHANGED_BEACON;
+	}
+
+	return changed;
+}
+
+/*
+ * mesh_sta_cleanup - clean up any mesh sta state
+ *
+ * @sta: mesh sta to clean up.
+ */
+void mesh_sta_cleanup(struct sta_info *sta)
+{
+	struct ieee80211_sub_if_data *sdata = sta->sdata;
+	u32 changed = mesh_plink_deactivate(sta);
+
+	if (changed)
+		ieee80211_mbss_info_change_notify(sdata, changed);
+}
+
+int mesh_rmc_init(struct ieee80211_sub_if_data *sdata)
+{
+	int i;
+
+	sdata->u.mesh.rmc = kmalloc(sizeof(struct mesh_rmc), GFP_KERNEL);
+	if (!sdata->u.mesh.rmc)
+		return -ENOMEM;
+	sdata->u.mesh.rmc->idx_mask = RMC_BUCKETS - 1;
+	for (i = 0; i < RMC_BUCKETS; i++)
+		INIT_HLIST_HEAD(&sdata->u.mesh.rmc->bucket[i]);
+	return 0;
+}
+
+void mesh_rmc_free(struct ieee80211_sub_if_data *sdata)
+{
+	struct mesh_rmc *rmc = sdata->u.mesh.rmc;
+	struct rmc_entry *p;
+	struct hlist_node *n;
+	int i;
+
+	if (!sdata->u.mesh.rmc)
+		return;
+
+	for (i = 0; i < RMC_BUCKETS; i++) {
+		hlist_for_each_entry_safe(p, n, &rmc->bucket[i], list) {
+			hlist_del(&p->list);
+			kmem_cache_free(rm_cache, p);
+		}
+	}
+
+	kfree(rmc);
+	sdata->u.mesh.rmc = NULL;
+}
+
+/**
+ * mesh_rmc_check - Check frame in recent multicast cache and add if absent.
+ *
+ * @sdata:	interface
+ * @sa:		source address
+ * @mesh_hdr:	mesh_header
+ *
+ * Returns: 0 if the frame is not in the cache, nonzero otherwise.
+ *
+ * Checks using the source address and the mesh sequence number if we have
+ * received this frame lately. If the frame is not in the cache, it is added to
+ * it.
+ */
+int mesh_rmc_check(struct ieee80211_sub_if_data *sdata,
+		   const u8 *sa, struct ieee80211s_hdr *mesh_hdr)
+{
+	struct mesh_rmc *rmc = sdata->u.mesh.rmc;
+	u32 seqnum = 0;
+	int entries = 0;
+	u8 idx;
+	struct rmc_entry *p;
+	struct hlist_node *n;
+
+	if (!rmc)
+		return -1;
+
+	/* Don't care about endianness since only match matters */
+	memcpy(&seqnum, &mesh_hdr->seqnum, sizeof(mesh_hdr->seqnum));
+	idx = le32_to_cpu(mesh_hdr->seqnum) & rmc->idx_mask;
+	hlist_for_each_entry_safe(p, n, &rmc->bucket[idx], list) {
+		++entries;
+		if (time_after(jiffies, p->exp_time) ||
+		    entries == RMC_QUEUE_MAX_LEN) {
+			hlist_del(&p->list);
+			kmem_cache_free(rm_cache, p);
+			--entries;
+		} else if ((seqnum == p->seqnum) && ether_addr_equal(sa, p->sa))
+			return -1;
+	}
+
+	p = kmem_cache_alloc(rm_cache, GFP_ATOMIC);
+	if (!p)
+		return 0;
+
+	p->seqnum = seqnum;
+	p->exp_time = jiffies + RMC_TIMEOUT;
+	memcpy(p->sa, sa, ETH_ALEN);
+	hlist_add_head(&p->list, &rmc->bucket[idx]);
+	return 0;
+}
+
+int mesh_add_meshconf_ie(struct ieee80211_sub_if_data *sdata,
+			 struct sk_buff *skb)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	u8 *pos, neighbors;
+	u8 meshconf_len = sizeof(struct ieee80211_meshconf_ie);
+
+	if (skb_tailroom(skb) < 2 + meshconf_len)
+		return -ENOMEM;
+
+	pos = skb_put(skb, 2 + meshconf_len);
+	*pos++ = WLAN_EID_MESH_CONFIG;
+	*pos++ = meshconf_len;
+
+	/* save a pointer for quick updates in pre-tbtt */
+	ifmsh->meshconf_offset = pos - skb->data;
+
+	/* Active path selection protocol ID */
+	*pos++ = ifmsh->mesh_pp_id;
+	/* Active path selection metric ID   */
+	*pos++ = ifmsh->mesh_pm_id;
+	/* Congestion control mode identifier */
+	*pos++ = ifmsh->mesh_cc_id;
+	/* Synchronization protocol identifier */
+	*pos++ = ifmsh->mesh_sp_id;
+	/* Authentication Protocol identifier */
+	*pos++ = ifmsh->mesh_auth_id;
+	/* Mesh Formation Info - number of neighbors */
+	neighbors = atomic_read(&ifmsh->estab_plinks);
+	neighbors = min_t(int, neighbors, IEEE80211_MAX_MESH_PEERINGS);
+	*pos++ = neighbors << 1;
+	/* Mesh capability */
+	*pos = 0x00;
+	*pos |= ifmsh->mshcfg.dot11MeshForwarding ?
+			IEEE80211_MESHCONF_CAPAB_FORWARDING : 0x00;
+	*pos |= ifmsh->accepting_plinks ?
+			IEEE80211_MESHCONF_CAPAB_ACCEPT_PLINKS : 0x00;
+	/* Mesh PS mode. See IEEE802.11-2012 8.4.2.100.8 */
+	*pos |= ifmsh->ps_peers_deep_sleep ?
+			IEEE80211_MESHCONF_CAPAB_POWER_SAVE_LEVEL : 0x00;
+	return 0;
+}
+
+int mesh_add_meshid_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	u8 *pos;
+
+	if (skb_tailroom(skb) < 2 + ifmsh->mesh_id_len)
+		return -ENOMEM;
+
+	pos = skb_put(skb, 2 + ifmsh->mesh_id_len);
+	*pos++ = WLAN_EID_MESH_ID;
+	*pos++ = ifmsh->mesh_id_len;
+	if (ifmsh->mesh_id_len)
+		memcpy(pos, ifmsh->mesh_id, ifmsh->mesh_id_len);
+
+	return 0;
+}
+
+static int mesh_add_awake_window_ie(struct ieee80211_sub_if_data *sdata,
+				    struct sk_buff *skb)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	u8 *pos;
+
+	/* see IEEE802.11-2012 13.14.6 */
+	if (ifmsh->ps_peers_light_sleep == 0 &&
+	    ifmsh->ps_peers_deep_sleep == 0 &&
+	    ifmsh->nonpeer_pm == NL80211_MESH_POWER_ACTIVE)
+		return 0;
+
+	if (skb_tailroom(skb) < 4)
+		return -ENOMEM;
+
+	pos = skb_put(skb, 2 + 2);
+	*pos++ = WLAN_EID_MESH_AWAKE_WINDOW;
+	*pos++ = 2;
+	put_unaligned_le16(ifmsh->mshcfg.dot11MeshAwakeWindowDuration, pos);
+
+	return 0;
+}
+
+int mesh_add_vendor_ies(struct ieee80211_sub_if_data *sdata,
+			struct sk_buff *skb)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	u8 offset, len;
+	const u8 *data;
+
+	if (!ifmsh->ie || !ifmsh->ie_len)
+		return 0;
+
+	/* fast-forward to vendor IEs */
+	offset = ieee80211_ie_split_vendor(ifmsh->ie, ifmsh->ie_len, 0);
+
+	if (offset < ifmsh->ie_len) {
+		len = ifmsh->ie_len - offset;
+		data = ifmsh->ie + offset;
+		if (skb_tailroom(skb) < len)
+			return -ENOMEM;
+		skb_put_data(skb, data, len);
+	}
+
+	return 0;
+}
+
+int mesh_add_rsn_ie(struct ieee80211_sub_if_data *sdata, struct sk_buff *skb)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	u8 len = 0;
+	const u8 *data;
+
+	if (!ifmsh->ie || !ifmsh->ie_len)
+		return 0;
+
+	/* find RSN IE */
+	data = cfg80211_find_ie(WLAN_EID_RSN, ifmsh->ie, ifmsh->ie_len);
+	if (!data)
+		return 0;
+
+	len = data[1] + 2;
+
+	if (skb_tailroom(skb) < len)
+		return -ENOMEM;
+	skb_put_data(skb, data, len);
+
+	return 0;
+}
+
+static int mesh_add_ds_params_ie(struct ieee80211_sub_if_data *sdata,
+				 struct sk_buff *skb)
+{
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct ieee80211_channel *chan;
+	u8 *pos;
+
+	if (skb_tailroom(skb) < 3)
+		return -ENOMEM;
+
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (WARN_ON(!chanctx_conf)) {
+		rcu_read_unlock();
+		return -EINVAL;
+	}
+	chan = chanctx_conf->def.chan;
+	rcu_read_unlock();
+
+	pos = skb_put(skb, 2 + 1);
+	*pos++ = WLAN_EID_DS_PARAMS;
+	*pos++ = 1;
+	*pos++ = ieee80211_frequency_to_channel(chan->center_freq);
+
+	return 0;
+}
+
+int mesh_add_ht_cap_ie(struct ieee80211_sub_if_data *sdata,
+		       struct sk_buff *skb)
+{
+	struct ieee80211_supported_band *sband;
+	u8 *pos;
+
+	sband = ieee80211_get_sband(sdata);
+	if (!sband)
+		return -EINVAL;
+
+	if (!sband->ht_cap.ht_supported ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
+		return 0;
+
+	if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_cap))
+		return -ENOMEM;
+
+	pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_cap));
+	ieee80211_ie_build_ht_cap(pos, &sband->ht_cap, sband->ht_cap.cap);
+
+	return 0;
+}
+
+int mesh_add_ht_oper_ie(struct ieee80211_sub_if_data *sdata,
+			struct sk_buff *skb)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct ieee80211_channel *channel;
+	struct ieee80211_supported_band *sband;
+	struct ieee80211_sta_ht_cap *ht_cap;
+	u8 *pos;
+
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (WARN_ON(!chanctx_conf)) {
+		rcu_read_unlock();
+		return -EINVAL;
+	}
+	channel = chanctx_conf->def.chan;
+	rcu_read_unlock();
+
+	sband = local->hw.wiphy->bands[channel->band];
+	ht_cap = &sband->ht_cap;
+
+	if (!ht_cap->ht_supported ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
+		return 0;
+
+	if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_ht_operation))
+		return -ENOMEM;
+
+	pos = skb_put(skb, 2 + sizeof(struct ieee80211_ht_operation));
+	ieee80211_ie_build_ht_oper(pos, ht_cap, &sdata->vif.bss_conf.chandef,
+				   sdata->vif.bss_conf.ht_operation_mode,
+				   false);
+
+	return 0;
+}
+
+int mesh_add_vht_cap_ie(struct ieee80211_sub_if_data *sdata,
+			struct sk_buff *skb)
+{
+	struct ieee80211_supported_band *sband;
+	u8 *pos;
+
+	sband = ieee80211_get_sband(sdata);
+	if (!sband)
+		return -EINVAL;
+
+	if (!sband->vht_cap.vht_supported ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
+		return 0;
+
+	if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_cap))
+		return -ENOMEM;
+
+	pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_cap));
+	ieee80211_ie_build_vht_cap(pos, &sband->vht_cap, sband->vht_cap.cap);
+
+	return 0;
+}
+
+int mesh_add_vht_oper_ie(struct ieee80211_sub_if_data *sdata,
+			 struct sk_buff *skb)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct ieee80211_channel *channel;
+	struct ieee80211_supported_band *sband;
+	struct ieee80211_sta_vht_cap *vht_cap;
+	u8 *pos;
+
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	if (WARN_ON(!chanctx_conf)) {
+		rcu_read_unlock();
+		return -EINVAL;
+	}
+	channel = chanctx_conf->def.chan;
+	rcu_read_unlock();
+
+	sband = local->hw.wiphy->bands[channel->band];
+	vht_cap = &sband->vht_cap;
+
+	if (!vht_cap->vht_supported ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_20_NOHT ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_5 ||
+	    sdata->vif.bss_conf.chandef.width == NL80211_CHAN_WIDTH_10)
+		return 0;
+
+	if (skb_tailroom(skb) < 2 + sizeof(struct ieee80211_vht_operation))
+		return -ENOMEM;
+
+	pos = skb_put(skb, 2 + sizeof(struct ieee80211_vht_operation));
+	ieee80211_ie_build_vht_oper(pos, vht_cap,
+				    &sdata->vif.bss_conf.chandef);
+
+	return 0;
+}
+
+static void ieee80211_mesh_path_timer(struct timer_list *t)
+{
+	struct ieee80211_sub_if_data *sdata =
+		from_timer(sdata, t, u.mesh.mesh_path_timer);
+
+	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+}
+
+static void ieee80211_mesh_path_root_timer(struct timer_list *t)
+{
+	struct ieee80211_sub_if_data *sdata =
+		from_timer(sdata, t, u.mesh.mesh_path_root_timer);
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+
+	set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
+
+	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+}
+
+void ieee80211_mesh_root_setup(struct ieee80211_if_mesh *ifmsh)
+{
+	if (ifmsh->mshcfg.dot11MeshHWMPRootMode > IEEE80211_ROOTMODE_ROOT)
+		set_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
+	else {
+		clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags);
+		/* stop running timer */
+		del_timer_sync(&ifmsh->mesh_path_root_timer);
+	}
+}
+
+/**
+ * ieee80211_fill_mesh_addresses - fill addresses of a locally originated mesh frame
+ * @hdr:	802.11 frame header
+ * @fc:		frame control field
+ * @meshda:	destination address in the mesh
+ * @meshsa:	source address address in the mesh.  Same as TA, as frame is
+ *              locally originated.
+ *
+ * Return the length of the 802.11 (does not include a mesh control header)
+ */
+int ieee80211_fill_mesh_addresses(struct ieee80211_hdr *hdr, __le16 *fc,
+				  const u8 *meshda, const u8 *meshsa)
+{
+	if (is_multicast_ether_addr(meshda)) {
+		*fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS);
+		/* DA TA SA */
+		memcpy(hdr->addr1, meshda, ETH_ALEN);
+		memcpy(hdr->addr2, meshsa, ETH_ALEN);
+		memcpy(hdr->addr3, meshsa, ETH_ALEN);
+		return 24;
+	} else {
+		*fc |= cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FCTL_TODS);
+		/* RA TA DA SA */
+		eth_zero_addr(hdr->addr1);   /* RA is resolved later */
+		memcpy(hdr->addr2, meshsa, ETH_ALEN);
+		memcpy(hdr->addr3, meshda, ETH_ALEN);
+		memcpy(hdr->addr4, meshsa, ETH_ALEN);
+		return 30;
+	}
+}
+
+/**
+ * ieee80211_new_mesh_header - create a new mesh header
+ * @sdata:	mesh interface to be used
+ * @meshhdr:    uninitialized mesh header
+ * @addr4or5:   1st address in the ae header, which may correspond to address 4
+ *              (if addr6 is NULL) or address 5 (if addr6 is present). It may
+ *              be NULL.
+ * @addr6:	2nd address in the ae header, which corresponds to addr6 of the
+ *              mesh frame
+ *
+ * Return the header length.
+ */
+unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata,
+				       struct ieee80211s_hdr *meshhdr,
+				       const char *addr4or5, const char *addr6)
+{
+	if (WARN_ON(!addr4or5 && addr6))
+		return 0;
+
+	memset(meshhdr, 0, sizeof(*meshhdr));
+
+	meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL;
+
+	/* FIXME: racy -- TX on multiple queues can be concurrent */
+	put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum);
+	sdata->u.mesh.mesh_seqnum++;
+
+	if (addr4or5 && !addr6) {
+		meshhdr->flags |= MESH_FLAGS_AE_A4;
+		memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
+		return 2 * ETH_ALEN;
+	} else if (addr4or5 && addr6) {
+		meshhdr->flags |= MESH_FLAGS_AE_A5_A6;
+		memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN);
+		memcpy(meshhdr->eaddr2, addr6, ETH_ALEN);
+		return 3 * ETH_ALEN;
+	}
+
+	return ETH_ALEN;
+}
+
+static void ieee80211_mesh_housekeeping(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	u32 changed;
+
+	if (ifmsh->mshcfg.plink_timeout > 0)
+		ieee80211_sta_expire(sdata, ifmsh->mshcfg.plink_timeout * HZ);
+	mesh_path_expire(sdata);
+
+	changed = mesh_accept_plinks_update(sdata);
+	ieee80211_mbss_info_change_notify(sdata, changed);
+
+	mod_timer(&ifmsh->housekeeping_timer,
+		  round_jiffies(jiffies +
+				IEEE80211_MESH_HOUSEKEEPING_INTERVAL));
+}
+
+static void ieee80211_mesh_rootpath(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	u32 interval;
+
+	mesh_path_tx_root_frame(sdata);
+
+	if (ifmsh->mshcfg.dot11MeshHWMPRootMode == IEEE80211_PROACTIVE_RANN)
+		interval = ifmsh->mshcfg.dot11MeshHWMPRannInterval;
+	else
+		interval = ifmsh->mshcfg.dot11MeshHWMProotInterval;
+
+	mod_timer(&ifmsh->mesh_path_root_timer,
+		  round_jiffies(TU_TO_EXP_TIME(interval)));
+}
+
+static int
+ieee80211_mesh_build_beacon(struct ieee80211_if_mesh *ifmsh)
+{
+	struct beacon_data *bcn;
+	int head_len, tail_len;
+	struct sk_buff *skb;
+	struct ieee80211_mgmt *mgmt;
+	struct ieee80211_chanctx_conf *chanctx_conf;
+	struct mesh_csa_settings *csa;
+	enum nl80211_band band;
+	u8 *pos;
+	struct ieee80211_sub_if_data *sdata;
+	int hdr_len = offsetofend(struct ieee80211_mgmt, u.beacon);
+
+	sdata = container_of(ifmsh, struct ieee80211_sub_if_data, u.mesh);
+	rcu_read_lock();
+	chanctx_conf = rcu_dereference(sdata->vif.chanctx_conf);
+	band = chanctx_conf->def.chan->band;
+	rcu_read_unlock();
+
+	head_len = hdr_len +
+		   2 + /* NULL SSID */
+		   /* Channel Switch Announcement */
+		   2 + sizeof(struct ieee80211_channel_sw_ie) +
+		   /* Mesh Channel Switch Parameters */
+		   2 + sizeof(struct ieee80211_mesh_chansw_params_ie) +
+		   /* Channel Switch Wrapper + Wide Bandwidth CSA IE */
+		   2 + 2 + sizeof(struct ieee80211_wide_bw_chansw_ie) +
+		   2 + sizeof(struct ieee80211_sec_chan_offs_ie) +
+		   2 + 8 + /* supported rates */
+		   2 + 3; /* DS params */
+	tail_len = 2 + (IEEE80211_MAX_SUPP_RATES - 8) +
+		   2 + sizeof(struct ieee80211_ht_cap) +
+		   2 + sizeof(struct ieee80211_ht_operation) +
+		   2 + ifmsh->mesh_id_len +
+		   2 + sizeof(struct ieee80211_meshconf_ie) +
+		   2 + sizeof(__le16) + /* awake window */
+		   2 + sizeof(struct ieee80211_vht_cap) +
+		   2 + sizeof(struct ieee80211_vht_operation) +
+		   ifmsh->ie_len;
+
+	bcn = kzalloc(sizeof(*bcn) + head_len + tail_len, GFP_KERNEL);
+	/* need an skb for IE builders to operate on */
+	skb = dev_alloc_skb(max(head_len, tail_len));
+
+	if (!bcn || !skb)
+		goto out_free;
+
+	/*
+	 * pointers go into the block we allocated,
+	 * memory is | beacon_data | head | tail |
+	 */
+	bcn->head = ((u8 *) bcn) + sizeof(*bcn);
+
+	/* fill in the head */
+	mgmt = skb_put_zero(skb, hdr_len);
+	mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+					  IEEE80211_STYPE_BEACON);
+	eth_broadcast_addr(mgmt->da);
+	memcpy(mgmt->sa, sdata->vif.addr, ETH_ALEN);
+	memcpy(mgmt->bssid, sdata->vif.addr, ETH_ALEN);
+	ieee80211_mps_set_frame_flags(sdata, NULL, (void *) mgmt);
+	mgmt->u.beacon.beacon_int =
+		cpu_to_le16(sdata->vif.bss_conf.beacon_int);
+	mgmt->u.beacon.capab_info |= cpu_to_le16(
+		sdata->u.mesh.security ? WLAN_CAPABILITY_PRIVACY : 0);
+
+	pos = skb_put(skb, 2);
+	*pos++ = WLAN_EID_SSID;
+	*pos++ = 0x0;
+
+	rcu_read_lock();
+	csa = rcu_dereference(ifmsh->csa);
+	if (csa) {
+		enum nl80211_channel_type ct;
+		struct cfg80211_chan_def *chandef;
+		int ie_len = 2 + sizeof(struct ieee80211_channel_sw_ie) +
+			     2 + sizeof(struct ieee80211_mesh_chansw_params_ie);
+
+		pos = skb_put_zero(skb, ie_len);
+		*pos++ = WLAN_EID_CHANNEL_SWITCH;
+		*pos++ = 3;
+		*pos++ = 0x0;
+		*pos++ = ieee80211_frequency_to_channel(
+				csa->settings.chandef.chan->center_freq);
+		bcn->csa_current_counter = csa->settings.count;
+		bcn->csa_counter_offsets[0] = hdr_len + 6;
+		*pos++ = csa->settings.count;
+		*pos++ = WLAN_EID_CHAN_SWITCH_PARAM;
+		*pos++ = 6;
+		if (ifmsh->csa_role == IEEE80211_MESH_CSA_ROLE_INIT) {
+			*pos++ = ifmsh->mshcfg.dot11MeshTTL;
+			*pos |= WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
+		} else {
+			*pos++ = ifmsh->chsw_ttl;
+		}
+		*pos++ |= csa->settings.block_tx ?
+			  WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT : 0x00;
+		put_unaligned_le16(WLAN_REASON_MESH_CHAN, pos);
+		pos += 2;
+		put_unaligned_le16(ifmsh->pre_value, pos);
+		pos += 2;
+
+		switch (csa->settings.chandef.width) {
+		case NL80211_CHAN_WIDTH_40:
+			ie_len = 2 + sizeof(struct ieee80211_sec_chan_offs_ie);
+			pos = skb_put_zero(skb, ie_len);
+
+			*pos++ = WLAN_EID_SECONDARY_CHANNEL_OFFSET; /* EID */
+			*pos++ = 1;				    /* len */
+			ct = cfg80211_get_chandef_type(&csa->settings.chandef);
+			if (ct == NL80211_CHAN_HT40PLUS)
+				*pos++ = IEEE80211_HT_PARAM_CHA_SEC_ABOVE;
+			else
+				*pos++ = IEEE80211_HT_PARAM_CHA_SEC_BELOW;
+			break;
+		case NL80211_CHAN_WIDTH_80:
+		case NL80211_CHAN_WIDTH_80P80:
+		case NL80211_CHAN_WIDTH_160:
+			/* Channel Switch Wrapper + Wide Bandwidth CSA IE */
+			ie_len = 2 + 2 +
+				 sizeof(struct ieee80211_wide_bw_chansw_ie);
+			pos = skb_put_zero(skb, ie_len);
+
+			*pos++ = WLAN_EID_CHANNEL_SWITCH_WRAPPER; /* EID */
+			*pos++ = 5;				  /* len */
+			/* put sub IE */
+			chandef = &csa->settings.chandef;
+			ieee80211_ie_build_wide_bw_cs(pos, chandef);
+			break;
+		default:
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	if (ieee80211_add_srates_ie(sdata, skb, true, band) ||
+	    mesh_add_ds_params_ie(sdata, skb))
+		goto out_free;
+
+	bcn->head_len = skb->len;
+	memcpy(bcn->head, skb->data, bcn->head_len);
+
+	/* now the tail */
+	skb_trim(skb, 0);
+	bcn->tail = bcn->head + bcn->head_len;
+
+	if (ieee80211_add_ext_srates_ie(sdata, skb, true, band) ||
+	    mesh_add_rsn_ie(sdata, skb) ||
+	    mesh_add_ht_cap_ie(sdata, skb) ||
+	    mesh_add_ht_oper_ie(sdata, skb) ||
+	    mesh_add_meshid_ie(sdata, skb) ||
+	    mesh_add_meshconf_ie(sdata, skb) ||
+	    mesh_add_awake_window_ie(sdata, skb) ||
+	    mesh_add_vht_cap_ie(sdata, skb) ||
+	    mesh_add_vht_oper_ie(sdata, skb) ||
+	    mesh_add_vendor_ies(sdata, skb))
+		goto out_free;
+
+	bcn->tail_len = skb->len;
+	memcpy(bcn->tail, skb->data, bcn->tail_len);
+	bcn->meshconf = (struct ieee80211_meshconf_ie *)
+					(bcn->tail + ifmsh->meshconf_offset);
+
+	dev_kfree_skb(skb);
+	rcu_assign_pointer(ifmsh->beacon, bcn);
+	return 0;
+out_free:
+	kfree(bcn);
+	dev_kfree_skb(skb);
+	return -ENOMEM;
+}
+
+static int
+ieee80211_mesh_rebuild_beacon(struct ieee80211_sub_if_data *sdata)
+{
+	struct beacon_data *old_bcn;
+	int ret;
+
+	old_bcn = rcu_dereference_protected(sdata->u.mesh.beacon,
+					    lockdep_is_held(&sdata->wdev.mtx));
+	ret = ieee80211_mesh_build_beacon(&sdata->u.mesh);
+	if (ret)
+		/* just reuse old beacon */
+		return ret;
+
+	if (old_bcn)
+		kfree_rcu(old_bcn, rcu_head);
+	return 0;
+}
+
+void ieee80211_mbss_info_change_notify(struct ieee80211_sub_if_data *sdata,
+				       u32 changed)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	unsigned long bits = changed;
+	u32 bit;
+
+	if (!bits)
+		return;
+
+	/* if we race with running work, worst case this work becomes a noop */
+	for_each_set_bit(bit, &bits, sizeof(changed) * BITS_PER_BYTE)
+		set_bit(bit, &ifmsh->mbss_changed);
+	set_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags);
+	ieee80211_queue_work(&sdata->local->hw, &sdata->work);
+}
+
+int ieee80211_start_mesh(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	struct ieee80211_local *local = sdata->local;
+	u32 changed = BSS_CHANGED_BEACON |
+		      BSS_CHANGED_BEACON_ENABLED |
+		      BSS_CHANGED_HT |
+		      BSS_CHANGED_BASIC_RATES |
+		      BSS_CHANGED_BEACON_INT |
+		      BSS_CHANGED_MCAST_RATE;
+
+	local->fif_other_bss++;
+	/* mesh ifaces must set allmulti to forward mcast traffic */
+	atomic_inc(&local->iff_allmultis);
+	ieee80211_configure_filter(local);
+
+	ifmsh->mesh_cc_id = 0;	/* Disabled */
+	/* register sync ops from extensible synchronization framework */
+	ifmsh->sync_ops = ieee80211_mesh_sync_ops_get(ifmsh->mesh_sp_id);
+	ifmsh->sync_offset_clockdrift_max = 0;
+	set_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags);
+	ieee80211_mesh_root_setup(ifmsh);
+	ieee80211_queue_work(&local->hw, &sdata->work);
+	sdata->vif.bss_conf.ht_operation_mode =
+				ifmsh->mshcfg.ht_opmode;
+	sdata->vif.bss_conf.enable_beacon = true;
+
+	changed |= ieee80211_mps_local_status_update(sdata);
+
+	if (ieee80211_mesh_build_beacon(ifmsh)) {
+		ieee80211_stop_mesh(sdata);
+		return -ENOMEM;
+	}
+
+	ieee80211_recalc_dtim(local, sdata);
+	ieee80211_bss_info_change_notify(sdata, changed);
+
+	netif_carrier_on(sdata->dev);
+	return 0;
+}
+
+void ieee80211_stop_mesh(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	struct beacon_data *bcn;
+
+	netif_carrier_off(sdata->dev);
+
+	/* flush STAs and mpaths on this iface */
+	sta_info_flush(sdata);
+	ieee80211_free_keys(sdata, true);
+	mesh_path_flush_by_iface(sdata);
+
+	/* stop the beacon */
+	ifmsh->mesh_id_len = 0;
+	sdata->vif.bss_conf.enable_beacon = false;
+	clear_bit(SDATA_STATE_OFFCHANNEL_BEACON_STOPPED, &sdata->state);
+	ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON_ENABLED);
+
+	/* remove beacon */
+	bcn = rcu_dereference_protected(ifmsh->beacon,
+					lockdep_is_held(&sdata->wdev.mtx));
+	RCU_INIT_POINTER(ifmsh->beacon, NULL);
+	kfree_rcu(bcn, rcu_head);
+
+	/* free all potentially still buffered group-addressed frames */
+	local->total_ps_buffered -= skb_queue_len(&ifmsh->ps.bc_buf);
+	skb_queue_purge(&ifmsh->ps.bc_buf);
+
+	del_timer_sync(&sdata->u.mesh.housekeeping_timer);
+	del_timer_sync(&sdata->u.mesh.mesh_path_root_timer);
+	del_timer_sync(&sdata->u.mesh.mesh_path_timer);
+
+	/* clear any mesh work (for next join) we may have accrued */
+	ifmsh->wrkq_flags = 0;
+	ifmsh->mbss_changed = 0;
+
+	local->fif_other_bss--;
+	atomic_dec(&local->iff_allmultis);
+	ieee80211_configure_filter(local);
+}
+
+static void ieee80211_mesh_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
+{
+	int err;
+
+	/* if the current channel is a DFS channel, mark the channel as
+	 * unavailable.
+	 */
+	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
+					    &sdata->vif.bss_conf.chandef,
+					    NL80211_IFTYPE_MESH_POINT);
+	if (err > 0)
+		cfg80211_radar_event(sdata->local->hw.wiphy,
+				     &sdata->vif.bss_conf.chandef, GFP_ATOMIC);
+}
+
+static bool
+ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
+				 struct ieee802_11_elems *elems, bool beacon)
+{
+	struct cfg80211_csa_settings params;
+	struct ieee80211_csa_ie csa_ie;
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	struct ieee80211_supported_band *sband;
+	int err;
+	u32 sta_flags;
+
+	sdata_assert_lock(sdata);
+
+	sband = ieee80211_get_sband(sdata);
+	if (!sband)
+		return false;
+
+	sta_flags = 0;
+	switch (sdata->vif.bss_conf.chandef.width) {
+	case NL80211_CHAN_WIDTH_20_NOHT:
+		sta_flags |= IEEE80211_STA_DISABLE_HT;
+		/* fall through */
+	case NL80211_CHAN_WIDTH_20:
+		sta_flags |= IEEE80211_STA_DISABLE_40MHZ;
+		/* fall through */
+	case NL80211_CHAN_WIDTH_40:
+		sta_flags |= IEEE80211_STA_DISABLE_VHT;
+		break;
+	default:
+		break;
+	}
+
+	memset(&params, 0, sizeof(params));
+	err = ieee80211_parse_ch_switch_ie(sdata, elems, sband->band,
+					   sta_flags, sdata->vif.addr,
+					   &csa_ie);
+	if (err < 0)
+		return false;
+	if (err)
+		return false;
+
+	/* Mark the channel unavailable if the reason for the switch is
+	 * regulatory.
+	 */
+	if (csa_ie.reason_code == WLAN_REASON_MESH_CHAN_REGULATORY)
+		ieee80211_mesh_csa_mark_radar(sdata);
+
+	params.chandef = csa_ie.chandef;
+	params.count = csa_ie.count;
+
+	if (!cfg80211_chandef_usable(sdata->local->hw.wiphy, &params.chandef,
+				     IEEE80211_CHAN_DISABLED) ||
+	    !cfg80211_reg_can_beacon(sdata->local->hw.wiphy, &params.chandef,
+				     NL80211_IFTYPE_MESH_POINT)) {
+		sdata_info(sdata,
+			   "mesh STA %pM switches to unsupported channel (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
+			   sdata->vif.addr,
+			   params.chandef.chan->center_freq,
+			   params.chandef.width,
+			   params.chandef.center_freq1,
+			   params.chandef.center_freq2);
+		return false;
+	}
+
+	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
+					    &params.chandef,
+					    NL80211_IFTYPE_MESH_POINT);
+	if (err < 0)
+		return false;
+	if (err > 0 && !ifmsh->userspace_handles_dfs) {
+		sdata_info(sdata,
+			   "mesh STA %pM switches to channel requiring DFS (%d MHz, width:%d, CF1/2: %d/%d MHz), aborting\n",
+			   sdata->vif.addr,
+			   params.chandef.chan->center_freq,
+			   params.chandef.width,
+			   params.chandef.center_freq1,
+			   params.chandef.center_freq2);
+		return false;
+	}
+
+	params.radar_required = err;
+
+	if (cfg80211_chandef_identical(&params.chandef,
+				       &sdata->vif.bss_conf.chandef)) {
+		mcsa_dbg(sdata,
+			 "received csa with an identical chandef, ignoring\n");
+		return true;
+	}
+
+	mcsa_dbg(sdata,
+		 "received channel switch announcement to go to channel %d MHz\n",
+		 params.chandef.chan->center_freq);
+
+	params.block_tx = csa_ie.mode & WLAN_EID_CHAN_SWITCH_PARAM_TX_RESTRICT;
+	if (beacon) {
+		ifmsh->chsw_ttl = csa_ie.ttl - 1;
+		if (ifmsh->pre_value >= csa_ie.pre_value)
+			return false;
+		ifmsh->pre_value = csa_ie.pre_value;
+	}
+
+	if (ifmsh->chsw_ttl >= ifmsh->mshcfg.dot11MeshTTL)
+		return false;
+
+	ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_REPEATER;
+
+	if (ieee80211_channel_switch(sdata->local->hw.wiphy, sdata->dev,
+				     &params) < 0)
+		return false;
+
+	return true;
+}
+
+static void
+ieee80211_mesh_rx_probe_req(struct ieee80211_sub_if_data *sdata,
+			    struct ieee80211_mgmt *mgmt, size_t len)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	struct sk_buff *presp;
+	struct beacon_data *bcn;
+	struct ieee80211_mgmt *hdr;
+	struct ieee802_11_elems elems;
+	size_t baselen;
+	u8 *pos;
+
+	pos = mgmt->u.probe_req.variable;
+	baselen = (u8 *) pos - (u8 *) mgmt;
+	if (baselen > len)
+		return;
+
+	ieee802_11_parse_elems(pos, len - baselen, false, &elems);
+
+	if (!elems.mesh_id)
+		return;
+
+	/* 802.11-2012 10.1.4.3.2 */
+	if ((!ether_addr_equal(mgmt->da, sdata->vif.addr) &&
+	     !is_broadcast_ether_addr(mgmt->da)) ||
+	    elems.ssid_len != 0)
+		return;
+
+	if (elems.mesh_id_len != 0 &&
+	    (elems.mesh_id_len != ifmsh->mesh_id_len ||
+	     memcmp(elems.mesh_id, ifmsh->mesh_id, ifmsh->mesh_id_len)))
+		return;
+
+	rcu_read_lock();
+	bcn = rcu_dereference(ifmsh->beacon);
+
+	if (!bcn)
+		goto out;
+
+	presp = dev_alloc_skb(local->tx_headroom +
+			      bcn->head_len + bcn->tail_len);
+	if (!presp)
+		goto out;
+
+	skb_reserve(presp, local->tx_headroom);
+	skb_put_data(presp, bcn->head, bcn->head_len);
+	skb_put_data(presp, bcn->tail, bcn->tail_len);
+	hdr = (struct ieee80211_mgmt *) presp->data;
+	hdr->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+					 IEEE80211_STYPE_PROBE_RESP);
+	memcpy(hdr->da, mgmt->sa, ETH_ALEN);
+	IEEE80211_SKB_CB(presp)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
+	ieee80211_tx_skb(sdata, presp);
+out:
+	rcu_read_unlock();
+}
+
+static void ieee80211_mesh_rx_bcn_presp(struct ieee80211_sub_if_data *sdata,
+					u16 stype,
+					struct ieee80211_mgmt *mgmt,
+					size_t len,
+					struct ieee80211_rx_status *rx_status)
+{
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	struct ieee802_11_elems elems;
+	struct ieee80211_channel *channel;
+	size_t baselen;
+	int freq;
+	enum nl80211_band band = rx_status->band;
+
+	/* ignore ProbeResp to foreign address */
+	if (stype == IEEE80211_STYPE_PROBE_RESP &&
+	    !ether_addr_equal(mgmt->da, sdata->vif.addr))
+		return;
+
+	baselen = (u8 *) mgmt->u.probe_resp.variable - (u8 *) mgmt;
+	if (baselen > len)
+		return;
+
+	ieee802_11_parse_elems(mgmt->u.probe_resp.variable, len - baselen,
+			       false, &elems);
+
+	/* ignore non-mesh or secure / unsecure mismatch */
+	if ((!elems.mesh_id || !elems.mesh_config) ||
+	    (elems.rsn && sdata->u.mesh.security == IEEE80211_MESH_SEC_NONE) ||
+	    (!elems.rsn && sdata->u.mesh.security != IEEE80211_MESH_SEC_NONE))
+		return;
+
+	if (elems.ds_params)
+		freq = ieee80211_channel_to_frequency(elems.ds_params[0], band);
+	else
+		freq = rx_status->freq;
+
+	channel = ieee80211_get_channel(local->hw.wiphy, freq);
+
+	if (!channel || channel->flags & IEEE80211_CHAN_DISABLED)
+		return;
+
+	if (mesh_matches_local(sdata, &elems)) {
+		mpl_dbg(sdata, "rssi_threshold=%d,rx_status->signal=%d\n",
+			sdata->u.mesh.mshcfg.rssi_threshold, rx_status->signal);
+		if (!sdata->u.mesh.user_mpm ||
+		    sdata->u.mesh.mshcfg.rssi_threshold == 0 ||
+		    sdata->u.mesh.mshcfg.rssi_threshold < rx_status->signal)
+			mesh_neighbour_update(sdata, mgmt->sa, &elems);
+	}
+
+	if (ifmsh->sync_ops)
+		ifmsh->sync_ops->rx_bcn_presp(sdata,
+			stype, mgmt, &elems, rx_status);
+
+	if (ifmsh->csa_role != IEEE80211_MESH_CSA_ROLE_INIT &&
+	    !sdata->vif.csa_active)
+		ieee80211_mesh_process_chnswitch(sdata, &elems, true);
+}
+
+int ieee80211_mesh_finish_csa(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	struct mesh_csa_settings *tmp_csa_settings;
+	int ret = 0;
+	int changed = 0;
+
+	/* Reset the TTL value and Initiator flag */
+	ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
+	ifmsh->chsw_ttl = 0;
+
+	/* Remove the CSA and MCSP elements from the beacon */
+	tmp_csa_settings = rcu_dereference_protected(ifmsh->csa,
+					    lockdep_is_held(&sdata->wdev.mtx));
+	RCU_INIT_POINTER(ifmsh->csa, NULL);
+	if (tmp_csa_settings)
+		kfree_rcu(tmp_csa_settings, rcu_head);
+	ret = ieee80211_mesh_rebuild_beacon(sdata);
+	if (ret)
+		return -EINVAL;
+
+	changed |= BSS_CHANGED_BEACON;
+
+	mcsa_dbg(sdata, "complete switching to center freq %d MHz",
+		 sdata->vif.bss_conf.chandef.chan->center_freq);
+	return changed;
+}
+
+int ieee80211_mesh_csa_beacon(struct ieee80211_sub_if_data *sdata,
+			      struct cfg80211_csa_settings *csa_settings)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	struct mesh_csa_settings *tmp_csa_settings;
+	int ret = 0;
+
+	lockdep_assert_held(&sdata->wdev.mtx);
+
+	tmp_csa_settings = kmalloc(sizeof(*tmp_csa_settings),
+				   GFP_ATOMIC);
+	if (!tmp_csa_settings)
+		return -ENOMEM;
+
+	memcpy(&tmp_csa_settings->settings, csa_settings,
+	       sizeof(struct cfg80211_csa_settings));
+
+	rcu_assign_pointer(ifmsh->csa, tmp_csa_settings);
+
+	ret = ieee80211_mesh_rebuild_beacon(sdata);
+	if (ret) {
+		tmp_csa_settings = rcu_dereference(ifmsh->csa);
+		RCU_INIT_POINTER(ifmsh->csa, NULL);
+		kfree_rcu(tmp_csa_settings, rcu_head);
+		return ret;
+	}
+
+	return BSS_CHANGED_BEACON;
+}
+
+static int mesh_fwd_csa_frame(struct ieee80211_sub_if_data *sdata,
+			       struct ieee80211_mgmt *mgmt, size_t len,
+			       struct ieee802_11_elems *elems)
+{
+	struct ieee80211_mgmt *mgmt_fwd;
+	struct sk_buff *skb;
+	struct ieee80211_local *local = sdata->local;
+
+	skb = dev_alloc_skb(local->tx_headroom + len);
+	if (!skb)
+		return -ENOMEM;
+	skb_reserve(skb, local->tx_headroom);
+	mgmt_fwd = skb_put(skb, len);
+
+	elems->mesh_chansw_params_ie->mesh_ttl--;
+	elems->mesh_chansw_params_ie->mesh_flags &=
+		~WLAN_EID_CHAN_SWITCH_PARAM_INITIATOR;
+
+	memcpy(mgmt_fwd, mgmt, len);
+	eth_broadcast_addr(mgmt_fwd->da);
+	memcpy(mgmt_fwd->sa, sdata->vif.addr, ETH_ALEN);
+	memcpy(mgmt_fwd->bssid, sdata->vif.addr, ETH_ALEN);
+
+	ieee80211_tx_skb(sdata, skb);
+	return 0;
+}
+
+static void mesh_rx_csa_frame(struct ieee80211_sub_if_data *sdata,
+			      struct ieee80211_mgmt *mgmt, size_t len)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	struct ieee802_11_elems elems;
+	u16 pre_value;
+	bool fwd_csa = true;
+	size_t baselen;
+	u8 *pos;
+
+	if (mgmt->u.action.u.measurement.action_code !=
+	    WLAN_ACTION_SPCT_CHL_SWITCH)
+		return;
+
+	pos = mgmt->u.action.u.chan_switch.variable;
+	baselen = offsetof(struct ieee80211_mgmt,
+			   u.action.u.chan_switch.variable);
+	ieee802_11_parse_elems(pos, len - baselen, true, &elems);
+
+	ifmsh->chsw_ttl = elems.mesh_chansw_params_ie->mesh_ttl;
+	if (!--ifmsh->chsw_ttl)
+		fwd_csa = false;
+
+	pre_value = le16_to_cpu(elems.mesh_chansw_params_ie->mesh_pre_value);
+	if (ifmsh->pre_value >= pre_value)
+		return;
+
+	ifmsh->pre_value = pre_value;
+
+	if (!sdata->vif.csa_active &&
+	    !ieee80211_mesh_process_chnswitch(sdata, &elems, false)) {
+		mcsa_dbg(sdata, "Failed to process CSA action frame");
+		return;
+	}
+
+	/* forward or re-broadcast the CSA frame */
+	if (fwd_csa) {
+		if (mesh_fwd_csa_frame(sdata, mgmt, len, &elems) < 0)
+			mcsa_dbg(sdata, "Failed to forward the CSA frame");
+	}
+}
+
+static void ieee80211_mesh_rx_mgmt_action(struct ieee80211_sub_if_data *sdata,
+					  struct ieee80211_mgmt *mgmt,
+					  size_t len,
+					  struct ieee80211_rx_status *rx_status)
+{
+	switch (mgmt->u.action.category) {
+	case WLAN_CATEGORY_SELF_PROTECTED:
+		switch (mgmt->u.action.u.self_prot.action_code) {
+		case WLAN_SP_MESH_PEERING_OPEN:
+		case WLAN_SP_MESH_PEERING_CLOSE:
+		case WLAN_SP_MESH_PEERING_CONFIRM:
+			mesh_rx_plink_frame(sdata, mgmt, len, rx_status);
+			break;
+		}
+		break;
+	case WLAN_CATEGORY_MESH_ACTION:
+		if (mesh_action_is_path_sel(mgmt))
+			mesh_rx_path_sel_frame(sdata, mgmt, len);
+		break;
+	case WLAN_CATEGORY_SPECTRUM_MGMT:
+		mesh_rx_csa_frame(sdata, mgmt, len);
+		break;
+	}
+}
+
+void ieee80211_mesh_rx_queued_mgmt(struct ieee80211_sub_if_data *sdata,
+				   struct sk_buff *skb)
+{
+	struct ieee80211_rx_status *rx_status;
+	struct ieee80211_mgmt *mgmt;
+	u16 stype;
+
+	sdata_lock(sdata);
+
+	/* mesh already went down */
+	if (!sdata->u.mesh.mesh_id_len)
+		goto out;
+
+	rx_status = IEEE80211_SKB_RXCB(skb);
+	mgmt = (struct ieee80211_mgmt *) skb->data;
+	stype = le16_to_cpu(mgmt->frame_control) & IEEE80211_FCTL_STYPE;
+
+	switch (stype) {
+	case IEEE80211_STYPE_PROBE_RESP:
+	case IEEE80211_STYPE_BEACON:
+		ieee80211_mesh_rx_bcn_presp(sdata, stype, mgmt, skb->len,
+					    rx_status);
+		break;
+	case IEEE80211_STYPE_PROBE_REQ:
+		ieee80211_mesh_rx_probe_req(sdata, mgmt, skb->len);
+		break;
+	case IEEE80211_STYPE_ACTION:
+		ieee80211_mesh_rx_mgmt_action(sdata, mgmt, skb->len, rx_status);
+		break;
+	}
+out:
+	sdata_unlock(sdata);
+}
+
+static void mesh_bss_info_changed(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	u32 bit, changed = 0;
+
+	for_each_set_bit(bit, &ifmsh->mbss_changed,
+			 sizeof(changed) * BITS_PER_BYTE) {
+		clear_bit(bit, &ifmsh->mbss_changed);
+		changed |= BIT(bit);
+	}
+
+	if (sdata->vif.bss_conf.enable_beacon &&
+	    (changed & (BSS_CHANGED_BEACON |
+			BSS_CHANGED_HT |
+			BSS_CHANGED_BASIC_RATES |
+			BSS_CHANGED_BEACON_INT)))
+		if (ieee80211_mesh_rebuild_beacon(sdata))
+			return;
+
+	ieee80211_bss_info_change_notify(sdata, changed);
+}
+
+void ieee80211_mesh_work(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+
+	sdata_lock(sdata);
+
+	/* mesh already went down */
+	if (!sdata->u.mesh.mesh_id_len)
+		goto out;
+
+	if (ifmsh->preq_queue_len &&
+	    time_after(jiffies,
+		       ifmsh->last_preq + msecs_to_jiffies(ifmsh->mshcfg.dot11MeshHWMPpreqMinInterval)))
+		mesh_path_start_discovery(sdata);
+
+	if (test_and_clear_bit(MESH_WORK_HOUSEKEEPING, &ifmsh->wrkq_flags))
+		ieee80211_mesh_housekeeping(sdata);
+
+	if (test_and_clear_bit(MESH_WORK_ROOT, &ifmsh->wrkq_flags))
+		ieee80211_mesh_rootpath(sdata);
+
+	if (test_and_clear_bit(MESH_WORK_DRIFT_ADJUST, &ifmsh->wrkq_flags))
+		mesh_sync_adjust_tsf(sdata);
+
+	if (test_and_clear_bit(MESH_WORK_MBSS_CHANGED, &ifmsh->wrkq_flags))
+		mesh_bss_info_changed(sdata);
+out:
+	sdata_unlock(sdata);
+}
+
+
+void ieee80211_mesh_init_sdata(struct ieee80211_sub_if_data *sdata)
+{
+	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
+	static u8 zero_addr[ETH_ALEN] = {};
+
+	timer_setup(&ifmsh->housekeeping_timer,
+		    ieee80211_mesh_housekeeping_timer, 0);
+
+	ifmsh->accepting_plinks = true;
+	atomic_set(&ifmsh->mpaths, 0);
+	mesh_rmc_init(sdata);
+	ifmsh->last_preq = jiffies;
+	ifmsh->next_perr = jiffies;
+	ifmsh->csa_role = IEEE80211_MESH_CSA_ROLE_NONE;
+	/* Allocate all mesh structures when creating the first mesh interface. */
+	if (!mesh_allocated)
+		ieee80211s_init();
+
+	mesh_pathtbl_init(sdata);
+
+	timer_setup(&ifmsh->mesh_path_timer, ieee80211_mesh_path_timer, 0);
+	timer_setup(&ifmsh->mesh_path_root_timer,
+		    ieee80211_mesh_path_root_timer, 0);
+	INIT_LIST_HEAD(&ifmsh->preq_queue.list);
+	skb_queue_head_init(&ifmsh->ps.bc_buf);
+	spin_lock_init(&ifmsh->mesh_preq_queue_lock);
+	spin_lock_init(&ifmsh->sync_offset_lock);
+	RCU_INIT_POINTER(ifmsh->beacon, NULL);
+
+	sdata->vif.bss_conf.bssid = zero_addr;
+}
+
+void ieee80211_mesh_teardown_sdata(struct ieee80211_sub_if_data *sdata)
+{
+	mesh_rmc_free(sdata);
+	mesh_pathtbl_unregister(sdata);
+}