[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"

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;

	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);
		}
	}
}

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