[linux-block.git] / net / mac80211 / link.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * MLO link handling
 *
 * Copyright (C) 2022 Intel Corporation
 */
#include <linux/slab.h>
#include <linux/kernel.h>
#include <net/mac80211.h>
#include "ieee80211_i.h"
#include "driver-ops.h"
#include "key.h"
#include "debugfs_netdev.h"

void ieee80211_link_setup(struct ieee80211_link_data *link)
{
	if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
		ieee80211_mgd_setup_link(link);
}

void ieee80211_link_init(struct ieee80211_sub_if_data *sdata,
			 int link_id,
			 struct ieee80211_link_data *link,
			 struct ieee80211_bss_conf *link_conf)
{
	bool deflink = link_id < 0;

	if (link_id < 0)
		link_id = 0;

	rcu_assign_pointer(sdata->vif.link_conf[link_id], link_conf);
	rcu_assign_pointer(sdata->link[link_id], link);

	link->sdata = sdata;
	link->link_id = link_id;
	link->conf = link_conf;
	link_conf->link_id = link_id;
	link_conf->vif = &sdata->vif;

	INIT_WORK(&link->csa_finalize_work,
		  ieee80211_csa_finalize_work);
	INIT_WORK(&link->color_change_finalize_work,
		  ieee80211_color_change_finalize_work);
	INIT_DELAYED_WORK(&link->color_collision_detect_work,
			  ieee80211_color_collision_detection_work);
	INIT_LIST_HEAD(&link->assigned_chanctx_list);
	INIT_LIST_HEAD(&link->reserved_chanctx_list);
	INIT_DELAYED_WORK(&link->dfs_cac_timer_work,
			  ieee80211_dfs_cac_timer_work);

	if (!deflink) {
		switch (sdata->vif.type) {
		case NL80211_IFTYPE_AP:
			ether_addr_copy(link_conf->addr,
					sdata->wdev.links[link_id].addr);
			link_conf->bssid = link_conf->addr;
			WARN_ON(!(sdata->wdev.valid_links & BIT(link_id)));
			break;
		case NL80211_IFTYPE_STATION:
			/* station sets the bssid in ieee80211_mgd_setup_link */
			break;
		default:
			WARN_ON(1);
		}

		ieee80211_link_debugfs_add(link);
	}
}

void ieee80211_link_stop(struct ieee80211_link_data *link)
{
	if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
		ieee80211_mgd_stop_link(link);

	cancel_delayed_work_sync(&link->color_collision_detect_work);
	ieee80211_link_release_channel(link);
}

struct link_container {
	struct ieee80211_link_data data;
	struct ieee80211_bss_conf conf;
};

static void ieee80211_tear_down_links(struct ieee80211_sub_if_data *sdata,
				      struct link_container **links, u16 mask)
{
	struct ieee80211_link_data *link;
	LIST_HEAD(keys);
	unsigned int link_id;

	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
		if (!(mask & BIT(link_id)))
			continue;
		link = &links[link_id]->data;
		if (link_id == 0 && !link)
			link = &sdata->deflink;
		if (WARN_ON(!link))
			continue;
		ieee80211_remove_link_keys(link, &keys);
		ieee80211_link_debugfs_remove(link);
		ieee80211_link_stop(link);
	}

	synchronize_rcu();

	ieee80211_free_key_list(sdata->local, &keys);
}

static void ieee80211_free_links(struct ieee80211_sub_if_data *sdata,
				 struct link_container **links)
{
	unsigned int link_id;

	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++)
		kfree(links[link_id]);
}

static int ieee80211_check_dup_link_addrs(struct ieee80211_sub_if_data *sdata)
{
	unsigned int i, j;

	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) {
		struct ieee80211_link_data *link1;

		link1 = sdata_dereference(sdata->link[i], sdata);
		if (!link1)
			continue;
		for (j = i + 1; j < IEEE80211_MLD_MAX_NUM_LINKS; j++) {
			struct ieee80211_link_data *link2;

			link2 = sdata_dereference(sdata->link[j], sdata);
			if (!link2)
				continue;

			if (ether_addr_equal(link1->conf->addr,
					     link2->conf->addr))
				return -EALREADY;
		}
	}

	return 0;
}

static void ieee80211_set_vif_links_bitmaps(struct ieee80211_sub_if_data *sdata,
					    u16 links)
{
	sdata->vif.valid_links = links;

	if (!links) {
		sdata->vif.active_links = 0;
		return;
	}

	switch (sdata->vif.type) {
	case NL80211_IFTYPE_AP:
		/* in an AP all links are always active */
		sdata->vif.active_links = links;
		break;
	case NL80211_IFTYPE_STATION:
		if (sdata->vif.active_links)
			break;
		WARN_ON(hweight16(links) > 1);
		sdata->vif.active_links = links;
		break;
	default:
		WARN_ON(1);
	}
}

static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata,
				      struct link_container **to_free,
				      u16 new_links)
{
	u16 old_links = sdata->vif.valid_links;
	u16 old_active = sdata->vif.active_links;
	unsigned long add = new_links & ~old_links;
	unsigned long rem = old_links & ~new_links;
	unsigned int link_id;
	int ret;
	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS] = {}, *link;
	struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS];
	struct ieee80211_link_data *old_data[IEEE80211_MLD_MAX_NUM_LINKS];
	bool use_deflink = old_links == 0; /* set for error case */

	sdata_assert_lock(sdata);

	memset(to_free, 0, sizeof(links));

	if (old_links == new_links)
		return 0;

	/* if there were no old links, need to clear the pointers to deflink */
	if (!old_links)
		rem |= BIT(0);

	/* allocate new link structures first */
	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
		link = kzalloc(sizeof(*link), GFP_KERNEL);
		if (!link) {
			ret = -ENOMEM;
			goto free;
		}
		links[link_id] = link;
	}

	/* keep track of the old pointers for the driver */
	BUILD_BUG_ON(sizeof(old) != sizeof(sdata->vif.link_conf));
	memcpy(old, sdata->vif.link_conf, sizeof(old));
	/* and for us in error cases */
	BUILD_BUG_ON(sizeof(old_data) != sizeof(sdata->link));
	memcpy(old_data, sdata->link, sizeof(old_data));

	/* grab old links to free later */
	for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
		if (rcu_access_pointer(sdata->link[link_id]) != &sdata->deflink) {
			/*
			 * we must have allocated the data through this path so
			 * we know we can free both at the same time
			 */
			to_free[link_id] = container_of(rcu_access_pointer(sdata->link[link_id]),
							typeof(*links[link_id]),
							data);
		}

		RCU_INIT_POINTER(sdata->link[link_id], NULL);
		RCU_INIT_POINTER(sdata->vif.link_conf[link_id], NULL);
	}

	/* link them into data structures */
	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
		WARN_ON(!use_deflink &&
			rcu_access_pointer(sdata->link[link_id]) == &sdata->deflink);

		link = links[link_id];
		ieee80211_link_init(sdata, link_id, &link->data, &link->conf);
		ieee80211_link_setup(&link->data);
	}

	if (new_links == 0)
		ieee80211_link_init(sdata, -1, &sdata->deflink,
				    &sdata->vif.bss_conf);

	ret = ieee80211_check_dup_link_addrs(sdata);
	if (!ret) {
		/* for keys we will not be able to undo this */
		ieee80211_tear_down_links(sdata, to_free, rem);

		ieee80211_set_vif_links_bitmaps(sdata, new_links);

		/* tell the driver */
		ret = drv_change_vif_links(sdata->local, sdata,
					   old_links & old_active,
					   new_links & sdata->vif.active_links,
					   old);
	}

	if (ret) {
		/* restore config */
		memcpy(sdata->link, old_data, sizeof(old_data));
		memcpy(sdata->vif.link_conf, old, sizeof(old));
		ieee80211_set_vif_links_bitmaps(sdata, old_links);
		/* and free (only) the newly allocated links */
		memset(to_free, 0, sizeof(links));
		goto free;
	}

	/* use deflink/bss_conf again if and only if there are no more links */
	use_deflink = new_links == 0;

	goto deinit;
free:
	/* if we failed during allocation, only free all */
	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
		kfree(links[link_id]);
		links[link_id] = NULL;
	}
deinit:
	if (use_deflink)
		ieee80211_link_init(sdata, -1, &sdata->deflink,
				    &sdata->vif.bss_conf);
	return ret;
}

int ieee80211_vif_set_links(struct ieee80211_sub_if_data *sdata,
			    u16 new_links)
{
	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];
	int ret;

	ret = ieee80211_vif_update_links(sdata, links, new_links);
	ieee80211_free_links(sdata, links);

	return ret;
}

void ieee80211_vif_clear_links(struct ieee80211_sub_if_data *sdata)
{
	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];

	/*
	 * The locking here is different because when we free links
	 * in the station case we need to be able to cancel_work_sync()
	 * something that also takes the lock.
	 */

	sdata_lock(sdata);
	ieee80211_vif_update_links(sdata, links, 0);
	sdata_unlock(sdata);

	ieee80211_free_links(sdata, links);
}

static int _ieee80211_set_active_links(struct ieee80211_sub_if_data *sdata,
				       u16 active_links)
{
	struct ieee80211_bss_conf *link_confs[IEEE80211_MLD_MAX_NUM_LINKS];
	struct ieee80211_local *local = sdata->local;
	u16 old_active = sdata->vif.active_links;
	unsigned long rem = old_active & ~active_links;
	unsigned long add = active_links & ~old_active;
	struct sta_info *sta;
	unsigned int link_id;
	int ret, i;

	if (!ieee80211_sdata_running(sdata))
		return -ENETDOWN;

	if (sdata->vif.type != NL80211_IFTYPE_STATION)
		return -EINVAL;

	/* cannot activate links that don't exist */
	if (active_links & ~sdata->vif.valid_links)
		return -EINVAL;

	/* nothing to do */
	if (old_active == active_links)
		return 0;

	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++)
		link_confs[i] = sdata_dereference(sdata->vif.link_conf[i],
						  sdata);

	if (add) {
		sdata->vif.active_links |= active_links;
		ret = drv_change_vif_links(local, sdata,
					   old_active,
					   sdata->vif.active_links,
					   link_confs);
		if (ret) {
			sdata->vif.active_links = old_active;
			return ret;
		}
	}

	for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
		struct ieee80211_link_data *link;

		link = sdata_dereference(sdata->link[link_id], sdata);

		/* FIXME: kill TDLS connections on the link */

		ieee80211_link_release_channel(link);
	}

	list_for_each_entry(sta, &local->sta_list, list) {
		if (sdata != sta->sdata)
			continue;

		/* this is very temporary, but do it anyway */
		__ieee80211_sta_recalc_aggregates(sta,
						  old_active | active_links);

		ret = drv_change_sta_links(local, sdata, &sta->sta,
					   old_active,
					   old_active | active_links);
		WARN_ON_ONCE(ret);
	}

	ret = ieee80211_key_switch_links(sdata, rem, add);
	WARN_ON_ONCE(ret);

	list_for_each_entry(sta, &local->sta_list, list) {
		if (sdata != sta->sdata)
			continue;

		__ieee80211_sta_recalc_aggregates(sta, active_links);

		ret = drv_change_sta_links(local, sdata, &sta->sta,
					   old_active | active_links,
					   active_links);
		WARN_ON_ONCE(ret);

		/*
		 * Do it again, just in case - the driver might very
		 * well have called ieee80211_sta_recalc_aggregates()
		 * from there when filling in the new links, which
		 * would set it wrong since the vif's active links are
		 * not switched yet...
		 */
		__ieee80211_sta_recalc_aggregates(sta, active_links);
	}

	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
		struct ieee80211_link_data *link;

		link = sdata_dereference(sdata->link[link_id], sdata);

		ret = ieee80211_link_use_channel(link, &link->conf->chandef,
						 IEEE80211_CHANCTX_SHARED);
		WARN_ON_ONCE(ret);

		ieee80211_link_info_change_notify(sdata, link,
						  BSS_CHANGED_ERP_CTS_PROT |
						  BSS_CHANGED_ERP_PREAMBLE |
						  BSS_CHANGED_ERP_SLOT |
						  BSS_CHANGED_HT |
						  BSS_CHANGED_BASIC_RATES |
						  BSS_CHANGED_BSSID |
						  BSS_CHANGED_CQM |
						  BSS_CHANGED_QOS |
						  BSS_CHANGED_TXPOWER |
						  BSS_CHANGED_BANDWIDTH |
						  BSS_CHANGED_TWT |
						  BSS_CHANGED_HE_OBSS_PD |
						  BSS_CHANGED_HE_BSS_COLOR);
		ieee80211_mgd_set_link_qos_params(link);
	}

	old_active = sdata->vif.active_links;
	sdata->vif.active_links = active_links;

	if (rem) {
		ret = drv_change_vif_links(local, sdata, old_active,
					   active_links, link_confs);
		WARN_ON_ONCE(ret);
	}

	return 0;
}

int ieee80211_set_active_links(struct ieee80211_vif *vif, u16 active_links)
{
	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
	struct ieee80211_local *local = sdata->local;
	u16 old_active;
	int ret;

	sdata_lock(sdata);
	mutex_lock(&local->sta_mtx);
	mutex_lock(&local->mtx);
	mutex_lock(&local->key_mtx);
	old_active = sdata->vif.active_links;
	if (old_active & active_links) {
		/*
		 * if there's at least one link that stays active across
		 * the change then switch to it (to those) first, and
		 * then enable the additional links
		 */
		ret = _ieee80211_set_active_links(sdata,
						  old_active & active_links);
		if (!ret)
			ret = _ieee80211_set_active_links(sdata, active_links);
	} else {
		/* otherwise switch directly */
		ret = _ieee80211_set_active_links(sdata, active_links);
	}
	mutex_unlock(&local->key_mtx);
	mutex_unlock(&local->mtx);
	mutex_unlock(&local->sta_mtx);
	sdata_unlock(sdata);

	return ret;
}
EXPORT_SYMBOL_GPL(ieee80211_set_active_links);

void ieee80211_set_active_links_async(struct ieee80211_vif *vif,
				      u16 active_links)
{
	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);

	if (!ieee80211_sdata_running(sdata))
		return;

	if (sdata->vif.type != NL80211_IFTYPE_STATION)
		return;

	/* cannot activate links that don't exist */
	if (active_links & ~sdata->vif.valid_links)
		return;

	/* nothing to do */
	if (sdata->vif.active_links == active_links)
		return;

	sdata->desired_active_links = active_links;
	schedule_work(&sdata->activate_links_work);
}
EXPORT_SYMBOL_GPL(ieee80211_set_active_links_async);
Commit	Line	Data
e73b5e51 JB	1	// SPDX-License-Identifier: GPL-2.0-only
	2	/*
	3	* MLO link handling
	4	*
	5	* Copyright (C) 2022 Intel Corporation
	6	*/
	7	#include <linux/slab.h>
	8	#include <linux/kernel.h>
	9	#include <net/mac80211.h>
	10	#include "ieee80211_i.h"
	11	#include "driver-ops.h"
3d901102	12	#include "key.h"
170cd6a6	13	#include "debugfs_netdev.h"
e73b5e51 JB	14
	15	void ieee80211_link_setup(struct ieee80211_link_data *link)
	16	{
	17	if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
	18	ieee80211_mgd_setup_link(link);
	19	}
	20
	21	void ieee80211_link_init(struct ieee80211_sub_if_data *sdata,
	22	int link_id,
	23	struct ieee80211_link_data *link,
	24	struct ieee80211_bss_conf *link_conf)
	25	{
	26	bool deflink = link_id < 0;
	27
	28	if (link_id < 0)
	29	link_id = 0;
	30
	31	rcu_assign_pointer(sdata->vif.link_conf[link_id], link_conf);
	32	rcu_assign_pointer(sdata->link[link_id], link);
	33
	34	link->sdata = sdata;
	35	link->link_id = link_id;
	36	link->conf = link_conf;
	37	link_conf->link_id = link_id;
e1f113cc	38	link_conf->vif = &sdata->vif;
e73b5e51 JB	39
	40	INIT_WORK(&link->csa_finalize_work,
	41	ieee80211_csa_finalize_work);
	42	INIT_WORK(&link->color_change_finalize_work,
	43	ieee80211_color_change_finalize_work);
92881884 LB	44	INIT_DELAYED_WORK(&link->color_collision_detect_work,
92881884 LB	45	ieee80211_color_collision_detection_work);
e73b5e51 JB	46	INIT_LIST_HEAD(&link->assigned_chanctx_list);
	47	INIT_LIST_HEAD(&link->reserved_chanctx_list);
	48	INIT_DELAYED_WORK(&link->dfs_cac_timer_work,
	49	ieee80211_dfs_cac_timer_work);
	50
	51	if (!deflink) {
	52	switch (sdata->vif.type) {
	53	case NL80211_IFTYPE_AP:
	54	ether_addr_copy(link_conf->addr,
	55	sdata->wdev.links[link_id].addr);
	56	link_conf->bssid = link_conf->addr;
	57	WARN_ON(!(sdata->wdev.valid_links & BIT(link_id)));
	58	break;
	59	case NL80211_IFTYPE_STATION:
	60	/* station sets the bssid in ieee80211_mgd_setup_link */
	61	break;
	62	default:
	63	WARN_ON(1);
	64	}
170cd6a6 BB	65
170cd6a6 BB	66	ieee80211_link_debugfs_add(link);
e73b5e51 JB	67	}
	68	}
	69
	70	void ieee80211_link_stop(struct ieee80211_link_data *link)
	71	{
	72	if (link->sdata->vif.type == NL80211_IFTYPE_STATION)
	73	ieee80211_mgd_stop_link(link);
	74
92881884	75	cancel_delayed_work_sync(&link->color_collision_detect_work);
e73b5e51 JB	76	ieee80211_link_release_channel(link);
	77	}
	78
	79	struct link_container {
	80	struct ieee80211_link_data data;
	81	struct ieee80211_bss_conf conf;
	82	};
	83
efe9c2bf JB	84	static void ieee80211_tear_down_links(struct ieee80211_sub_if_data *sdata,
efe9c2bf JB	85	struct link_container **links, u16 mask)
e73b5e51	86	{
efe9c2bf	87	struct ieee80211_link_data *link;
e73b5e51 JB	88	LIST_HEAD(keys);
	89	unsigned int link_id;
	90
	91	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
efe9c2bf JB	92	if (!(mask & BIT(link_id)))
	93	continue;
	94	link = &links[link_id]->data;
	95	if (link_id == 0 && !link)
	96	link = &sdata->deflink;
	97	if (WARN_ON(!link))
e73b5e51	98	continue;
efe9c2bf	99	ieee80211_remove_link_keys(link, &keys);
170cd6a6	100	ieee80211_link_debugfs_remove(link);
efe9c2bf	101	ieee80211_link_stop(link);
e73b5e51 JB	102	}
	103
	104	synchronize_rcu();
	105
	106	ieee80211_free_key_list(sdata->local, &keys);
efe9c2bf	107	}
e73b5e51	108
efe9c2bf JB	109	static void ieee80211_free_links(struct ieee80211_sub_if_data *sdata,
	110	struct link_container **links)
	111	{
	112	unsigned int link_id;
	113
	114	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++)
e73b5e51	115	kfree(links[link_id]);
e73b5e51 JB	116	}
	117
	118	static int ieee80211_check_dup_link_addrs(struct ieee80211_sub_if_data *sdata)
	119	{
	120	unsigned int i, j;
	121
	122	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) {
	123	struct ieee80211_link_data *link1;
	124
	125	link1 = sdata_dereference(sdata->link[i], sdata);
	126	if (!link1)
	127	continue;
	128	for (j = i + 1; j < IEEE80211_MLD_MAX_NUM_LINKS; j++) {
	129	struct ieee80211_link_data *link2;
	130
	131	link2 = sdata_dereference(sdata->link[j], sdata);
	132	if (!link2)
	133	continue;
	134
	135	if (ether_addr_equal(link1->conf->addr,
	136	link2->conf->addr))
	137	return -EALREADY;
	138	}
	139	}
	140
	141	return 0;
	142	}
	143
efe9c2bf JB	144	static void ieee80211_set_vif_links_bitmaps(struct ieee80211_sub_if_data *sdata,
	145	u16 links)
	146	{
	147	sdata->vif.valid_links = links;
	148
	149	if (!links) {
	150	sdata->vif.active_links = 0;
	151	return;
	152	}
	153
	154	switch (sdata->vif.type) {
	155	case NL80211_IFTYPE_AP:
	156	/* in an AP all links are always active */
	157	sdata->vif.active_links = links;
	158	break;
	159	case NL80211_IFTYPE_STATION:
	160	if (sdata->vif.active_links)
	161	break;
	162	WARN_ON(hweight16(links) > 1);
	163	sdata->vif.active_links = links;
	164	break;
	165	default:
	166	WARN_ON(1);
	167	}
	168	}
	169
e73b5e51 JB	170	static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata,
	171	struct link_container **to_free,
	172	u16 new_links)
	173	{
	174	u16 old_links = sdata->vif.valid_links;
efe9c2bf	175	u16 old_active = sdata->vif.active_links;
e73b5e51 JB	176	unsigned long add = new_links & ~old_links;
	177	unsigned long rem = old_links & ~new_links;
	178	unsigned int link_id;
	179	int ret;
	180	struct link_container links[IEEE80211_MLD_MAX_NUM_LINKS] = {}, link;
	181	struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS];
	182	struct ieee80211_link_data *old_data[IEEE80211_MLD_MAX_NUM_LINKS];
	183	bool use_deflink = old_links == 0; /* set for error case */
	184
	185	sdata_assert_lock(sdata);
	186
	187	memset(to_free, 0, sizeof(links));
	188
	189	if (old_links == new_links)
	190	return 0;
	191
	192	/* if there were no old links, need to clear the pointers to deflink */
	193	if (!old_links)
	194	rem \|= BIT(0);
	195
	196	/* allocate new link structures first */
	197	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
	198	link = kzalloc(sizeof(*link), GFP_KERNEL);
	199	if (!link) {
	200	ret = -ENOMEM;
	201	goto free;
	202	}
	203	links[link_id] = link;
	204	}
	205
	206	/* keep track of the old pointers for the driver */
	207	BUILD_BUG_ON(sizeof(old) != sizeof(sdata->vif.link_conf));
	208	memcpy(old, sdata->vif.link_conf, sizeof(old));
	209	/* and for us in error cases */
	210	BUILD_BUG_ON(sizeof(old_data) != sizeof(sdata->link));
	211	memcpy(old_data, sdata->link, sizeof(old_data));
	212
	213	/* grab old links to free later */
	214	for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
	215	if (rcu_access_pointer(sdata->link[link_id]) != &sdata->deflink) {
	216	/*
	217	* we must have allocated the data through this path so
	218	* we know we can free both at the same time
	219	*/
	220	to_free[link_id] = container_of(rcu_access_pointer(sdata->link[link_id]),
	221	typeof(*links[link_id]),
	222	data);
	223	}
	224
	225	RCU_INIT_POINTER(sdata->link[link_id], NULL);
	226	RCU_INIT_POINTER(sdata->vif.link_conf[link_id], NULL);
	227	}
	228
	229	/* link them into data structures */
	230	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
	231	WARN_ON(!use_deflink &&
	232	rcu_access_pointer(sdata->link[link_id]) == &sdata->deflink);
	233
	234	link = links[link_id];
	235	ieee80211_link_init(sdata, link_id, &link->data, &link->conf);
	236	ieee80211_link_setup(&link->data);
	237	}
	238
	239	if (new_links == 0)
240	ieee80211_link_init(sdata, -1, &sdata->deflink,
241	&sdata->vif.bss_conf);
242
e73b5e51 JB	243	ret = ieee80211_check_dup_link_addrs(sdata);
e73b5e51 JB	244	if (!ret) {
efe9c2bf JB	245	/* for keys we will not be able to undo this */
	246	ieee80211_tear_down_links(sdata, to_free, rem);
	247
	248	ieee80211_set_vif_links_bitmaps(sdata, new_links);
	249
e73b5e51 JB	250	/* tell the driver */
e73b5e51 JB	251	ret = drv_change_vif_links(sdata->local, sdata,
efe9c2bf JB	252	old_links & old_active,
efe9c2bf JB	253	new_links & sdata->vif.active_links,
e73b5e51 JB	254	old);
	255	}
	256
	257	if (ret) {
	258	/* restore config */
	259	memcpy(sdata->link, old_data, sizeof(old_data));
	260	memcpy(sdata->vif.link_conf, old, sizeof(old));
efe9c2bf	261	ieee80211_set_vif_links_bitmaps(sdata, old_links);
e73b5e51 JB	262	/* and free (only) the newly allocated links */
	263	memset(to_free, 0, sizeof(links));
	264	goto free;
	265	}
	266
	267	/* use deflink/bss_conf again if and only if there are no more links */
	268	use_deflink = new_links == 0;
	269
	270	goto deinit;
	271	free:
	272	/* if we failed during allocation, only free all */
	273	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
	274	kfree(links[link_id]);
	275	links[link_id] = NULL;
	276	}
	277	deinit:
	278	if (use_deflink)
	279	ieee80211_link_init(sdata, -1, &sdata->deflink,
	280	&sdata->vif.bss_conf);
	281	return ret;
	282	}
	283
	284	int ieee80211_vif_set_links(struct ieee80211_sub_if_data *sdata,
	285	u16 new_links)
	286	{
	287	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];
	288	int ret;
	289
	290	ret = ieee80211_vif_update_links(sdata, links, new_links);
	291	ieee80211_free_links(sdata, links);
	292
	293	return ret;
	294	}
	295
	296	void ieee80211_vif_clear_links(struct ieee80211_sub_if_data *sdata)
	297	{
	298	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];
	299
	300	/*
	301	* The locking here is different because when we free links
	302	* in the station case we need to be able to cancel_work_sync()
	303	* something that also takes the lock.
	304	*/
	305
	306	sdata_lock(sdata);
	307	ieee80211_vif_update_links(sdata, links, 0);
	308	sdata_unlock(sdata);
	309
	310	ieee80211_free_links(sdata, links);
	311	}
3d901102 JB	312
	313	static int _ieee80211_set_active_links(struct ieee80211_sub_if_data *sdata,
	314	u16 active_links)
	315	{
	316	struct ieee80211_bss_conf *link_confs[IEEE80211_MLD_MAX_NUM_LINKS];
	317	struct ieee80211_local *local = sdata->local;
	318	u16 old_active = sdata->vif.active_links;
	319	unsigned long rem = old_active & ~active_links;
	320	unsigned long add = active_links & ~old_active;
	321	struct sta_info *sta;
	322	unsigned int link_id;
	323	int ret, i;
	324
	325	if (!ieee80211_sdata_running(sdata))
	326	return -ENETDOWN;
	327
	328	if (sdata->vif.type != NL80211_IFTYPE_STATION)
	329	return -EINVAL;
	330
	331	/* cannot activate links that don't exist */
	332	if (active_links & ~sdata->vif.valid_links)
	333	return -EINVAL;
	334
	335	/* nothing to do */
	336	if (old_active == active_links)
	337	return 0;
	338
	339	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++)
	340	link_confs[i] = sdata_dereference(sdata->vif.link_conf[i],
	341	sdata);
	342
	343	if (add) {
	344	sdata->vif.active_links \|= active_links;
	345	ret = drv_change_vif_links(local, sdata,
	346	old_active,
	347	sdata->vif.active_links,
	348	link_confs);
	349	if (ret) {
	350	sdata->vif.active_links = old_active;
	351	return ret;
	352	}
	353	}
	354
	355	for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
	356	struct ieee80211_link_data *link;
	357
	358	link = sdata_dereference(sdata->link[link_id], sdata);
	359
	360	/* FIXME: kill TDLS connections on the link */
	361
	362	ieee80211_link_release_channel(link);
	363	}
	364
	365	list_for_each_entry(sta, &local->sta_list, list) {
	366	if (sdata != sta->sdata)
	367	continue;
9b41a9d7 JB	368
	369	/* this is very temporary, but do it anyway */
	370	__ieee80211_sta_recalc_aggregates(sta,
	371	old_active \| active_links);
	372
3d901102 JB	373	ret = drv_change_sta_links(local, sdata, &sta->sta,
	374	old_active,
	375	old_active \| active_links);
	376	WARN_ON_ONCE(ret);
	377	}
	378
	379	ret = ieee80211_key_switch_links(sdata, rem, add);
	380	WARN_ON_ONCE(ret);
	381
	382	list_for_each_entry(sta, &local->sta_list, list) {
	383	if (sdata != sta->sdata)
	384	continue;
9b41a9d7 JB	385
	386	__ieee80211_sta_recalc_aggregates(sta, active_links);
	387
3d901102 JB	388	ret = drv_change_sta_links(local, sdata, &sta->sta,
	389	old_active \| active_links,
	390	active_links);
	391	WARN_ON_ONCE(ret);
9b41a9d7 JB	392
	393	/*
	394	* Do it again, just in case - the driver might very
	395	* well have called ieee80211_sta_recalc_aggregates()
	396	* from there when filling in the new links, which
	397	* would set it wrong since the vif's active links are
	398	* not switched yet...
	399	*/
	400	__ieee80211_sta_recalc_aggregates(sta, active_links);
3d901102 JB	401	}
	402
	403	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
	404	struct ieee80211_link_data *link;
	405
	406	link = sdata_dereference(sdata->link[link_id], sdata);
	407
	408	ret = ieee80211_link_use_channel(link, &link->conf->chandef,
	409	IEEE80211_CHANCTX_SHARED);
	410	WARN_ON_ONCE(ret);
	411
	412	ieee80211_link_info_change_notify(sdata, link,
	413	BSS_CHANGED_ERP_CTS_PROT \|
	414	BSS_CHANGED_ERP_PREAMBLE \|
	415	BSS_CHANGED_ERP_SLOT \|
	416	BSS_CHANGED_HT \|
	417	BSS_CHANGED_BASIC_RATES \|
	418	BSS_CHANGED_BSSID \|
	419	BSS_CHANGED_CQM \|
	420	BSS_CHANGED_QOS \|
	421	BSS_CHANGED_TXPOWER \|
	422	BSS_CHANGED_BANDWIDTH \|
	423	BSS_CHANGED_TWT \|
	424	BSS_CHANGED_HE_OBSS_PD \|
	425	BSS_CHANGED_HE_BSS_COLOR);
	426	ieee80211_mgd_set_link_qos_params(link);
	427	}
	428
	429	old_active = sdata->vif.active_links;
	430	sdata->vif.active_links = active_links;
	431
	432	if (rem) {
	433	ret = drv_change_vif_links(local, sdata, old_active,
	434	active_links, link_confs);
	435	WARN_ON_ONCE(ret);
	436	}
	437
	438	return 0;
	439	}
	440
	441	int ieee80211_set_active_links(struct ieee80211_vif *vif, u16 active_links)
	442	{
	443	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
	444	struct ieee80211_local *local = sdata->local;
	445	u16 old_active;
	446	int ret;
	447
	448	sdata_lock(sdata);
	449	mutex_lock(&local->sta_mtx);
	450	mutex_lock(&local->mtx);
	451	mutex_lock(&local->key_mtx);
	452	old_active = sdata->vif.active_links;
	453	if (old_active & active_links) {
	454	/*
	455	* if there's at least one link that stays active across
	456	* the change then switch to it (to those) first, and
	457	* then enable the additional links
	458	*/
	459	ret = _ieee80211_set_active_links(sdata,
	460	old_active & active_links);
	461	if (!ret)
	462	ret = _ieee80211_set_active_links(sdata, active_links);
	463	} else {
	464	/* otherwise switch directly */
465	ret = _ieee80211_set_active_links(sdata, active_links);
466	}
467	mutex_unlock(&local->key_mtx);
468	mutex_unlock(&local->mtx);
469	mutex_unlock(&local->sta_mtx);
470	sdata_unlock(sdata);
471
472	return ret;
473	}
474	EXPORT_SYMBOL_GPL(ieee80211_set_active_links);
475
476	void ieee80211_set_active_links_async(struct ieee80211_vif *vif,
477	u16 active_links)
478	{
479	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
480
481	if (!ieee80211_sdata_running(sdata))
482	return;
483
484	if (sdata->vif.type != NL80211_IFTYPE_STATION)
485	return;
486
487	/* cannot activate links that don't exist */
488	if (active_links & ~sdata->vif.valid_links)
489	return;
490
491	/* nothing to do */
492	if (sdata->vif.active_links == active_links)
493	return;
494
495	sdata->desired_active_links = active_links;
496	schedule_work(&sdata->activate_links_work);
497	}
498	EXPORT_SYMBOL_GPL(ieee80211_set_active_links_async);