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

// SPDX-License-Identifier: GPL-2.0-only
/*
 * MLO link handling
 *
 * Copyright (C) 2022-2024 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;

	wiphy_work_init(&link->csa_finalize_work,
			ieee80211_csa_finalize_work);
	wiphy_work_init(&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);
	wiphy_delayed_work_init(&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);
	wiphy_work_cancel(link->sdata->local->hw.wiphy,
			  &link->csa_finalize_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 valid_links, u16 dormant_links)
{
	sdata->vif.valid_links = valid_links;
	sdata->vif.dormant_links = dormant_links;

	if (!valid_links ||
	    WARN((~valid_links & dormant_links) ||
		 !(valid_links & ~dormant_links),
		 "Invalid links: valid=0x%x, dormant=0x%x",
		 valid_links, dormant_links)) {
		sdata->vif.active_links = 0;
		sdata->vif.dormant_links = 0;
		return;
	}

	switch (sdata->vif.type) {
	case NL80211_IFTYPE_AP:
		/* in an AP all links are always active */
		sdata->vif.active_links = valid_links;

		/* AP links are not expected to be disabled */
		WARN_ON(dormant_links);
		break;
	case NL80211_IFTYPE_STATION:
		if (sdata->vif.active_links)
			break;
		sdata->vif.active_links = valid_links & ~dormant_links;
		WARN_ON(hweight16(sdata->vif.active_links) > 1);
		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 dormant_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 */

	lockdep_assert_wiphy(sdata->local->hw.wiphy);

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

	if (old_links == new_links && dormant_links == sdata->vif.dormant_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);
	}

	if (!old_links)
		ieee80211_debugfs_recreate_netdev(sdata, true);

	/* 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, dormant_links);

		/* tell the driver */
		ret = drv_change_vif_links(sdata->local, sdata,
					   old_links & old_active,
					   new_links & sdata->vif.active_links,
					   old);
		if (!new_links)
			ieee80211_debugfs_recreate_netdev(sdata, false);
	}

	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, dormant_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, u16 dormant_links)
{
	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];
	int ret;

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

	return ret;
}

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;

	if (active_links & ~ieee80211_vif_usable_links(&sdata->vif))
		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);

		ieee80211_teardown_tdls_peers(link);

		__ieee80211_link_release_channel(link, true);
	}

	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);

		/*
		 * This call really should not fail. Unfortunately, it appears
		 * that this may happen occasionally with some drivers. Should
		 * it happen, we are stuck in a bad place as going backwards is
		 * not really feasible.
		 *
		 * So lets just tell link_use_channel that it must not fail to
		 * assign the channel context (from mac80211's perspective) and
		 * assume the driver is going to trigger a recovery flow if it
		 * had a failure.
		 * That really is not great nor guaranteed to work. But at least
		 * the internal mac80211 state remains consistent and there is
		 * a chance that we can recover.
		 */
		ret = _ieee80211_link_use_channel(link,
						  &link->conf->chanreq,
						  IEEE80211_CHANCTX_SHARED,
						  true);
		WARN_ON_ONCE(ret);

		ieee80211_mgd_set_link_qos_params(link);
		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);
	}

	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;

	lockdep_assert_wiphy(local->hw.wiphy);

	if (WARN_ON(!active_links))
		return -EINVAL;

	old_active = sdata->vif.active_links;
	if (old_active == active_links)
		return 0;

	if (!drv_can_activate_links(local, sdata, active_links))
		return -EINVAL;

	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);
	}

	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 (WARN_ON(!active_links))
		return;

	if (!ieee80211_sdata_running(sdata))
		return;

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

	if (active_links & ~ieee80211_vif_usable_links(&sdata->vif))
		return;

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

	sdata->desired_active_links = active_links;
	wiphy_work_queue(sdata->local->hw.wiphy, &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	*
b82730bf	5	* Copyright (C) 2022-2024 Intel Corporation
e73b5e51 JB	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	39
d7074be6 JB	40	wiphy_work_init(&link->csa_finalize_work,
d7074be6 JB	41	ieee80211_csa_finalize_work);
b38579ae JB	42	wiphy_work_init(&link->color_change_finalize_work,
b38579ae JB	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);
e73b5e51 JB	47	INIT_LIST_HEAD(&link->reserved_chanctx_list);
766d2601 JB	48	wiphy_delayed_work_init(&link->dfs_cac_timer_work,
766d2601 JB	49	ieee80211_dfs_cac_timer_work);
e73b5e51 JB	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);
1a96bb4e AKS	76	wiphy_work_cancel(link->sdata->local->hw.wiphy,
1a96bb4e AKS	77	&link->csa_finalize_work);
e73b5e51 JB	78	ieee80211_link_release_channel(link);
	79	}
	80
	81	struct link_container {
	82	struct ieee80211_link_data data;
	83	struct ieee80211_bss_conf conf;
	84	};
	85
efe9c2bf JB	86	static void ieee80211_tear_down_links(struct ieee80211_sub_if_data *sdata,
efe9c2bf JB	87	struct link_container **links, u16 mask)
e73b5e51	88	{
efe9c2bf	89	struct ieee80211_link_data *link;
e73b5e51 JB	90	LIST_HEAD(keys);
	91	unsigned int link_id;
	92
	93	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
efe9c2bf JB	94	if (!(mask & BIT(link_id)))
	95	continue;
	96	link = &links[link_id]->data;
	97	if (link_id == 0 && !link)
	98	link = &sdata->deflink;
	99	if (WARN_ON(!link))
e73b5e51	100	continue;
efe9c2bf	101	ieee80211_remove_link_keys(link, &keys);
170cd6a6	102	ieee80211_link_debugfs_remove(link);
efe9c2bf	103	ieee80211_link_stop(link);
e73b5e51 JB	104	}
	105
	106	synchronize_rcu();
	107
	108	ieee80211_free_key_list(sdata->local, &keys);
efe9c2bf	109	}
e73b5e51	110
efe9c2bf JB	111	static void ieee80211_free_links(struct ieee80211_sub_if_data *sdata,
	112	struct link_container **links)
	113	{
	114	unsigned int link_id;
	115
	116	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++)
e73b5e51	117	kfree(links[link_id]);
e73b5e51 JB	118	}
	119
	120	static int ieee80211_check_dup_link_addrs(struct ieee80211_sub_if_data *sdata)
	121	{
	122	unsigned int i, j;
	123
	124	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) {
	125	struct ieee80211_link_data *link1;
	126
	127	link1 = sdata_dereference(sdata->link[i], sdata);
	128	if (!link1)
	129	continue;
	130	for (j = i + 1; j < IEEE80211_MLD_MAX_NUM_LINKS; j++) {
	131	struct ieee80211_link_data *link2;
	132
	133	link2 = sdata_dereference(sdata->link[j], sdata);
	134	if (!link2)
	135	continue;
	136
	137	if (ether_addr_equal(link1->conf->addr,
	138	link2->conf->addr))
	139	return -EALREADY;
	140	}
	141	}
	142
	143	return 0;
	144	}
	145
efe9c2bf	146	static void ieee80211_set_vif_links_bitmaps(struct ieee80211_sub_if_data *sdata,
6d543b34	147	u16 valid_links, u16 dormant_links)
efe9c2bf	148	{
6d543b34 IP	149	sdata->vif.valid_links = valid_links;
	150	sdata->vif.dormant_links = dormant_links;
	151
	152	if (!valid_links \|\|
	153	WARN((~valid_links & dormant_links) \|\|
	154	!(valid_links & ~dormant_links),
	155	"Invalid links: valid=0x%x, dormant=0x%x",
	156	valid_links, dormant_links)) {
efe9c2bf	157	sdata->vif.active_links = 0;
6d543b34	158	sdata->vif.dormant_links = 0;
efe9c2bf JB	159	return;
	160	}
	161
	162	switch (sdata->vif.type) {
	163	case NL80211_IFTYPE_AP:
	164	/* in an AP all links are always active */
6d543b34 IP	165	sdata->vif.active_links = valid_links;
	166
	167	/* AP links are not expected to be disabled */
	168	WARN_ON(dormant_links);
efe9c2bf JB	169	break;
	170	case NL80211_IFTYPE_STATION:
	171	if (sdata->vif.active_links)
	172	break;
6d543b34 IP	173	sdata->vif.active_links = valid_links & ~dormant_links;
6d543b34 IP	174	WARN_ON(hweight16(sdata->vif.active_links) > 1);
efe9c2bf JB	175	break;
	176	default:
	177	WARN_ON(1);
	178	}
	179	}
	180
e73b5e51 JB	181	static int ieee80211_vif_update_links(struct ieee80211_sub_if_data *sdata,
e73b5e51 JB	182	struct link_container **to_free,
6d543b34	183	u16 new_links, u16 dormant_links)
e73b5e51 JB	184	{
e73b5e51 JB	185	u16 old_links = sdata->vif.valid_links;
efe9c2bf	186	u16 old_active = sdata->vif.active_links;
e73b5e51 JB	187	unsigned long add = new_links & ~old_links;
	188	unsigned long rem = old_links & ~new_links;
	189	unsigned int link_id;
	190	int ret;
	191	struct link_container links[IEEE80211_MLD_MAX_NUM_LINKS] = {}, link;
	192	struct ieee80211_bss_conf *old[IEEE80211_MLD_MAX_NUM_LINKS];
	193	struct ieee80211_link_data *old_data[IEEE80211_MLD_MAX_NUM_LINKS];
	194	bool use_deflink = old_links == 0; /* set for error case */
	195
076fc877	196	lockdep_assert_wiphy(sdata->local->hw.wiphy);
e73b5e51 JB	197
	198	memset(to_free, 0, sizeof(links));
	199
e7182c4e	200	if (old_links == new_links && dormant_links == sdata->vif.dormant_links)
e73b5e51 JB	201	return 0;
	202
	203	/* if there were no old links, need to clear the pointers to deflink */
	204	if (!old_links)
	205	rem \|= BIT(0);
	206
	207	/* allocate new link structures first */
	208	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
	209	link = kzalloc(sizeof(*link), GFP_KERNEL);
	210	if (!link) {
	211	ret = -ENOMEM;
	212	goto free;
	213	}
	214	links[link_id] = link;
	215	}
	216
	217	/* keep track of the old pointers for the driver */
	218	BUILD_BUG_ON(sizeof(old) != sizeof(sdata->vif.link_conf));
	219	memcpy(old, sdata->vif.link_conf, sizeof(old));
	220	/* and for us in error cases */
	221	BUILD_BUG_ON(sizeof(old_data) != sizeof(sdata->link));
	222	memcpy(old_data, sdata->link, sizeof(old_data));
	223
	224	/* grab old links to free later */
	225	for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
	226	if (rcu_access_pointer(sdata->link[link_id]) != &sdata->deflink) {
	227	/*
	228	* we must have allocated the data through this path so
	229	* we know we can free both at the same time
	230	*/
	231	to_free[link_id] = container_of(rcu_access_pointer(sdata->link[link_id]),
	232	typeof(*links[link_id]),
	233	data);
	234	}
	235
	236	RCU_INIT_POINTER(sdata->link[link_id], NULL);
	237	RCU_INIT_POINTER(sdata->vif.link_conf[link_id], NULL);
	238	}
	239
c942398f MK	240	if (!old_links)
	241	ieee80211_debugfs_recreate_netdev(sdata, true);
	242
e73b5e51 JB	243	/* link them into data structures */
	244	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
	245	WARN_ON(!use_deflink &&
	246	rcu_access_pointer(sdata->link[link_id]) == &sdata->deflink);
	247
	248	link = links[link_id];
	249	ieee80211_link_init(sdata, link_id, &link->data, &link->conf);
	250	ieee80211_link_setup(&link->data);
	251	}
	252
	253	if (new_links == 0)
	254	ieee80211_link_init(sdata, -1, &sdata->deflink,
	255	&sdata->vif.bss_conf);
	256
e73b5e51 JB	257	ret = ieee80211_check_dup_link_addrs(sdata);
e73b5e51 JB	258	if (!ret) {
efe9c2bf JB	259	/* for keys we will not be able to undo this */
	260	ieee80211_tear_down_links(sdata, to_free, rem);
	261
6d543b34	262	ieee80211_set_vif_links_bitmaps(sdata, new_links, dormant_links);
efe9c2bf	263
e73b5e51 JB	264	/* tell the driver */
e73b5e51 JB	265	ret = drv_change_vif_links(sdata->local, sdata,
efe9c2bf JB	266	old_links & old_active,
efe9c2bf JB	267	new_links & sdata->vif.active_links,
e73b5e51	268	old);
c942398f MK	269	if (!new_links)
c942398f MK	270	ieee80211_debugfs_recreate_netdev(sdata, false);
e73b5e51 JB	271	}
	272
	273	if (ret) {
	274	/* restore config */
	275	memcpy(sdata->link, old_data, sizeof(old_data));
	276	memcpy(sdata->vif.link_conf, old, sizeof(old));
6d543b34	277	ieee80211_set_vif_links_bitmaps(sdata, old_links, dormant_links);
e73b5e51 JB	278	/* and free (only) the newly allocated links */
	279	memset(to_free, 0, sizeof(links));
	280	goto free;
	281	}
	282
	283	/* use deflink/bss_conf again if and only if there are no more links */
	284	use_deflink = new_links == 0;
	285
	286	goto deinit;
	287	free:
	288	/* if we failed during allocation, only free all */
	289	for (link_id = 0; link_id < IEEE80211_MLD_MAX_NUM_LINKS; link_id++) {
	290	kfree(links[link_id]);
	291	links[link_id] = NULL;
	292	}
	293	deinit:
	294	if (use_deflink)
	295	ieee80211_link_init(sdata, -1, &sdata->deflink,
	296	&sdata->vif.bss_conf);
	297	return ret;
	298	}
	299
	300	int ieee80211_vif_set_links(struct ieee80211_sub_if_data *sdata,
6d543b34	301	u16 new_links, u16 dormant_links)
e73b5e51 JB	302	{
	303	struct link_container *links[IEEE80211_MLD_MAX_NUM_LINKS];
	304	int ret;
	305
6d543b34 IP	306	ret = ieee80211_vif_update_links(sdata, links, new_links,
6d543b34 IP	307	dormant_links);
e73b5e51 JB	308	ieee80211_free_links(sdata, links);
	309
	310	return ret;
	311	}
	312
3d901102 JB	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
f1871abd	331	if (active_links & ~ieee80211_vif_usable_links(&sdata->vif))
3d901102 JB	332	return -EINVAL;
	333
	334	/* nothing to do */
	335	if (old_active == active_links)
	336	return 0;
	337
	338	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++)
	339	link_confs[i] = sdata_dereference(sdata->vif.link_conf[i],
	340	sdata);
	341
	342	if (add) {
	343	sdata->vif.active_links \|= active_links;
	344	ret = drv_change_vif_links(local, sdata,
	345	old_active,
	346	sdata->vif.active_links,
	347	link_confs);
	348	if (ret) {
	349	sdata->vif.active_links = old_active;
	350	return ret;
	351	}
	352	}
	353
	354	for_each_set_bit(link_id, &rem, IEEE80211_MLD_MAX_NUM_LINKS) {
	355	struct ieee80211_link_data *link;
	356
	357	link = sdata_dereference(sdata->link[link_id], sdata);
	358
07fba227	359	ieee80211_teardown_tdls_peers(link);
3d901102	360
3c9ff1a1	361	__ieee80211_link_release_channel(link, true);
3d901102 JB	362	}
	363
	364	list_for_each_entry(sta, &local->sta_list, list) {
	365	if (sdata != sta->sdata)
	366	continue;
9b41a9d7 JB	367
	368	/* this is very temporary, but do it anyway */
	369	__ieee80211_sta_recalc_aggregates(sta,
	370	old_active \| active_links);
	371
3d901102 JB	372	ret = drv_change_sta_links(local, sdata, &sta->sta,
	373	old_active,
	374	old_active \| active_links);
	375	WARN_ON_ONCE(ret);
	376	}
	377
	378	ret = ieee80211_key_switch_links(sdata, rem, add);
	379	WARN_ON_ONCE(ret);
	380
	381	list_for_each_entry(sta, &local->sta_list, list) {
	382	if (sdata != sta->sdata)
	383	continue;
9b41a9d7 JB	384
	385	__ieee80211_sta_recalc_aggregates(sta, active_links);
	386
3d901102 JB	387	ret = drv_change_sta_links(local, sdata, &sta->sta,
	388	old_active \| active_links,
	389	active_links);
	390	WARN_ON_ONCE(ret);
9b41a9d7 JB	391
	392	/*
	393	* Do it again, just in case - the driver might very
	394	* well have called ieee80211_sta_recalc_aggregates()
	395	* from there when filling in the new links, which
	396	* would set it wrong since the vif's active links are
	397	* not switched yet...
	398	*/
	399	__ieee80211_sta_recalc_aggregates(sta, active_links);
3d901102 JB	400	}
	401
	402	for_each_set_bit(link_id, &add, IEEE80211_MLD_MAX_NUM_LINKS) {
	403	struct ieee80211_link_data *link;
	404
	405	link = sdata_dereference(sdata->link[link_id], sdata);
	406
cc3ea42c BB	407	/*
	408	* This call really should not fail. Unfortunately, it appears
	409	* that this may happen occasionally with some drivers. Should
	410	* it happen, we are stuck in a bad place as going backwards is
	411	* not really feasible.
	412	*
	413	* So lets just tell link_use_channel that it must not fail to
	414	* assign the channel context (from mac80211's perspective) and
	415	* assume the driver is going to trigger a recovery flow if it
	416	* had a failure.
	417	* That really is not great nor guaranteed to work. But at least
	418	* the internal mac80211 state remains consistent and there is
	419	* a chance that we can recover.
	420	*/
	421	ret = _ieee80211_link_use_channel(link,
	422	&link->conf->chanreq,
	423	IEEE80211_CHANCTX_SHARED,
	424	true);
3d901102 JB	425	WARN_ON_ONCE(ret);
3d901102 JB	426
01605ad6	427	ieee80211_mgd_set_link_qos_params(link);
3d901102 JB	428	ieee80211_link_info_change_notify(sdata, link,
	429	BSS_CHANGED_ERP_CTS_PROT \|
	430	BSS_CHANGED_ERP_PREAMBLE \|
	431	BSS_CHANGED_ERP_SLOT \|
	432	BSS_CHANGED_HT \|
	433	BSS_CHANGED_BASIC_RATES \|
	434	BSS_CHANGED_BSSID \|
	435	BSS_CHANGED_CQM \|
	436	BSS_CHANGED_QOS \|
	437	BSS_CHANGED_TXPOWER \|
	438	BSS_CHANGED_BANDWIDTH \|
	439	BSS_CHANGED_TWT \|
	440	BSS_CHANGED_HE_OBSS_PD \|
	441	BSS_CHANGED_HE_BSS_COLOR);
3d901102 JB	442	}
	443
	444	old_active = sdata->vif.active_links;
	445	sdata->vif.active_links = active_links;
	446
	447	if (rem) {
	448	ret = drv_change_vif_links(local, sdata, old_active,
	449	active_links, link_confs);
	450	WARN_ON_ONCE(ret);
	451	}
	452
	453	return 0;
	454	}
	455
076fc877	456	int ieee80211_set_active_links(struct ieee80211_vif *vif, u16 active_links)
3d901102 JB	457	{
	458	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
	459	struct ieee80211_local *local = sdata->local;
	460	u16 old_active;
	461	int ret;
	462
4d3acf43	463	lockdep_assert_wiphy(local->hw.wiphy);
2a8b665e	464
b341590e MK	465	if (WARN_ON(!active_links))
	466	return -EINVAL;
	467
2f51c87a JB	468	old_active = sdata->vif.active_links;
	469	if (old_active == active_links)
	470	return 0;
	471
e993af2e MK	472	if (!drv_can_activate_links(local, sdata, active_links))
	473	return -EINVAL;
	474
3d901102 JB	475	if (old_active & active_links) {
	476	/*
	477	* if there's at least one link that stays active across
	478	* the change then switch to it (to those) first, and
	479	* then enable the additional links
	480	*/
	481	ret = _ieee80211_set_active_links(sdata,
	482	old_active & active_links);
	483	if (!ret)
	484	ret = _ieee80211_set_active_links(sdata, active_links);
	485	} else {
	486	/* otherwise switch directly */
	487	ret = _ieee80211_set_active_links(sdata, active_links);
	488	}
79973d5c BB	489
	490	return ret;
	491	}
3d901102 JB	492	EXPORT_SYMBOL_GPL(ieee80211_set_active_links);
	493
	494	void ieee80211_set_active_links_async(struct ieee80211_vif *vif,
	495	u16 active_links)
	496	{
	497	struct ieee80211_sub_if_data *sdata = vif_to_sdata(vif);
	498
b341590e MK	499	if (WARN_ON(!active_links))
	500	return;
	501
3d901102 JB	502	if (!ieee80211_sdata_running(sdata))
	503	return;
	504
	505	if (sdata->vif.type != NL80211_IFTYPE_STATION)
	506	return;
	507
f1871abd	508	if (active_links & ~ieee80211_vif_usable_links(&sdata->vif))
3d901102 JB	509	return;
	510
	511	/* nothing to do */
	512	if (sdata->vif.active_links == active_links)
	513	return;
	514
	515	sdata->desired_active_links = active_links;
7206a948	516	wiphy_work_queue(sdata->local->hw.wiphy, &sdata->activate_links_work);
3d901102 JB	517	}
3d901102 JB	518	EXPORT_SYMBOL_GPL(ieee80211_set_active_links_async);