Commit 8eb8dd2f authored by Ilan Peer's avatar Ilan Peer Committed by Johannes Berg
Browse files

wifi: mac80211: Support link removal using Reconfiguration ML element 



Add support for handling link removal indicated by the
Reconfiguration Multi-Link element.

Signed-off-by: default avatarIlan Peer <ilan.peer@intel.com>
Signed-off-by: default avatarGregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230618214436.d8a046dc0c1a.I4dcf794da2a2d9f4e5f63a4b32158075d27c0660@changeid


[use cfg80211_links_removed() API instead]
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 79973d5c

include/linux/ieee80211.h

+33 −0
Original line number Diff line number Diff line
@@ -4891,6 +4891,39 @@ static inline bool ieee80211_mle_basic_sta_prof_size_ok(const u8 *data, 
	       fixed + prof->sta_info_len <= len;

}



#define IEEE80211_MLE_STA_RECONF_CONTROL_LINK_ID			0x000f

#define IEEE80211_MLE_STA_RECONF_CONTROL_COMPLETE_PROFILE		0x0010

#define IEEE80211_MLE_STA_RECONF_CONTROL_STA_MAC_ADDR_PRESENT		0x0020

#define IEEE80211_MLE_STA_RECONF_CONTROL_DELETE_TIMER_PRESENT		0x0040



/**

 * ieee80211_mle_reconf_sta_prof_size_ok - validate reconfiguration multi-link

 *	element sta profile size.

 * @data: pointer to the sub element data

 * @len: length of the containing sub element

 */

static inline bool ieee80211_mle_reconf_sta_prof_size_ok(const u8 *data,

							 size_t len)

{

	const struct ieee80211_mle_per_sta_profile *prof = (const void *)data;

	u16 control;

	u8 fixed = sizeof(*prof);

	u8 info_len = 1;



	if (len < fixed)

		return false;



	control = le16_to_cpu(prof->control);



	if (control & IEEE80211_MLE_STA_RECONF_CONTROL_STA_MAC_ADDR_PRESENT)

		info_len += ETH_ALEN;

	if (control & IEEE80211_MLE_STA_RECONF_CONTROL_DELETE_TIMER_PRESENT)

		info_len += 2;



	return prof->sta_info_len >= info_len &&

	       fixed + prof->sta_info_len - 1 <= len;

}



#define for_each_mle_subelement(_elem, _data, _len)			\

	if (ieee80211_mle_size_ok(_data, _len))				\

		for_each_element(_elem,					\

net/mac80211/ieee80211_i.h

+3 −0
Original line number Diff line number Diff line
@@ -551,6 +551,9 @@ struct ieee80211_if_managed { 
	 */

	u8 *assoc_req_ies;

	size_t assoc_req_ies_len;



	struct wiphy_delayed_work ml_reconf_work;

	u16 removed_links;

};



struct ieee80211_if_ibss {

net/mac80211/mlme.c

+169 −0
Original line number Diff line number Diff line
@@ -5608,6 +5608,169 @@ static bool ieee80211_config_puncturing(struct ieee80211_link_data *link, 
	return true;

}



static void ieee80211_ml_reconf_work(struct wiphy *wiphy,

				     struct wiphy_work *work)

{

	struct ieee80211_sub_if_data *sdata =

		container_of(work, struct ieee80211_sub_if_data,

			     u.mgd.ml_reconf_work.work);

	u16 new_valid_links, new_active_links, new_dormant_links;

	int ret;



	sdata_lock(sdata);

	if (!sdata->u.mgd.removed_links) {

		sdata_unlock(sdata);

		return;

	}



	sdata_info(sdata,

		   "MLO Reconfiguration: work: valid=0x%x, removed=0x%x\n",

		   sdata->vif.valid_links, sdata->u.mgd.removed_links);



	new_valid_links = sdata->vif.valid_links & ~sdata->u.mgd.removed_links;

	if (new_valid_links == sdata->vif.valid_links) {

		sdata_unlock(sdata);

		return;

	}



	if (!new_valid_links ||

	    !(new_valid_links & ~sdata->vif.dormant_links)) {

		sdata_info(sdata, "No valid links after reconfiguration\n");

		ret = -EINVAL;

		goto out;

	}



	new_active_links = sdata->vif.active_links & ~sdata->u.mgd.removed_links;

	if (new_active_links != sdata->vif.active_links) {

		if (!new_active_links)

			new_active_links =

				BIT(ffs(new_valid_links &

					~sdata->vif.dormant_links) - 1);



		ret = __ieee80211_set_active_links(&sdata->vif,

						   new_active_links);

		if (ret) {

			sdata_info(sdata,

				   "Failed setting active links\n");

			goto out;

		}

	}



	new_dormant_links = sdata->vif.dormant_links & ~sdata->u.mgd.removed_links;



	ret = ieee80211_vif_set_links(sdata, new_valid_links,

				      new_dormant_links);

	if (ret)

		sdata_info(sdata, "Failed setting valid links\n");



out:

	if (!ret)

		cfg80211_links_removed(sdata->dev, sdata->u.mgd.removed_links);

	else

		___ieee80211_disconnect(sdata);



	sdata->u.mgd.removed_links = 0;



	sdata_unlock(sdata);

}



static void ieee80211_ml_reconfiguration(struct ieee80211_sub_if_data *sdata,

					 struct ieee802_11_elems *elems)

{

	const struct ieee80211_multi_link_elem *ml;

	const struct element *sub;

	size_t ml_len;

	unsigned long removed_links = 0;

	u16 link_removal_timeout[IEEE80211_MLD_MAX_NUM_LINKS] = {};

	u8 link_id;

	u32 delay;



	if (!ieee80211_vif_is_mld(&sdata->vif) || !elems->ml_reconf)

		return;



	ml_len = cfg80211_defragment_element(elems->ml_reconf_elem,

					     elems->ie_start,

					     elems->total_len,

					     elems->scratch_pos,

					     elems->scratch + elems->scratch_len -

					     elems->scratch_pos,

					     WLAN_EID_FRAGMENT);



	elems->ml_reconf = (const void *)elems->scratch_pos;

	elems->ml_reconf_len = ml_len;

	ml = elems->ml_reconf;



	/* Directly parse the sub elements as the common information doesn't

	 * hold any useful information.

	 */

	for_each_mle_subelement(sub, (u8 *)ml, ml_len) {

		struct ieee80211_mle_per_sta_profile *prof = (void *)sub->data;

		u8 *pos = prof->variable;

		u16 control;



		if (sub->id != IEEE80211_MLE_SUBELEM_PER_STA_PROFILE)

			continue;



		if (!ieee80211_mle_reconf_sta_prof_size_ok(sub->data,

							   sub->datalen))

			return;



		control = le16_to_cpu(prof->control);

		link_id = control & IEEE80211_MLE_STA_RECONF_CONTROL_LINK_ID;



		removed_links |= BIT(link_id);



		/* the MAC address should not be included, but handle it */

		if (control &

		    IEEE80211_MLE_STA_RECONF_CONTROL_STA_MAC_ADDR_PRESENT)

			pos += 6;



		/* According to Draft P802.11be_D3.0, the control should

		 * include the AP Removal Timer present. If the AP Removal Timer

		 * is not present assume immediate removal.

		 */

		if (control &

		    IEEE80211_MLE_STA_RECONF_CONTROL_DELETE_TIMER_PRESENT)

			link_removal_timeout[link_id] = le16_to_cpu(*(__le16 *)pos);

	}



	removed_links &= sdata->vif.valid_links;

	if (!removed_links) {

		/* In case the removal was cancelled, abort it */

		if (sdata->u.mgd.removed_links) {

			sdata->u.mgd.removed_links = 0;

			wiphy_delayed_work_cancel(sdata->local->hw.wiphy,

						  &sdata->u.mgd.ml_reconf_work);

		}

		return;

	}



	delay = 0;

	for_each_set_bit(link_id, &removed_links, IEEE80211_MLD_MAX_NUM_LINKS) {

		struct ieee80211_bss_conf *link_conf =

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

		u32 link_delay;



		if (!link_conf) {

			removed_links &= ~BIT(link_id);

			continue;

		}



		link_delay = link_conf->beacon_int *

			link_removal_timeout[link_id];



		if (!delay)

			delay = link_delay;

		else

			delay = min(delay, link_delay);

	}



	sdata->u.mgd.removed_links = removed_links;

	wiphy_delayed_work_queue(sdata->local->hw.wiphy,

				 &sdata->u.mgd.ml_reconf_work,

				 TU_TO_JIFFIES(delay));

}



static void ieee80211_rx_mgmt_beacon(struct ieee80211_link_data *link,

				     struct ieee80211_hdr *hdr, size_t len,

				     struct ieee80211_rx_status *rx_status)
@@ -5937,6 +6100,8 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_link_data *link, 
		}

	}



	ieee80211_ml_reconfiguration(sdata, elems);



	ieee80211_link_info_change_notify(sdata, link, changed);

free:

	kfree(elems);
@@ -6563,6 +6728,8 @@ void ieee80211_sta_setup_sdata(struct ieee80211_sub_if_data *sdata) 
			ieee80211_csa_connection_drop_work);

	INIT_DELAYED_WORK(&ifmgd->tdls_peer_del_work,

			  ieee80211_tdls_peer_del_work);

	wiphy_delayed_work_init(&ifmgd->ml_reconf_work,

				ieee80211_ml_reconf_work);

	timer_setup(&ifmgd->timer, ieee80211_sta_timer, 0);

	timer_setup(&ifmgd->bcn_mon_timer, ieee80211_sta_bcn_mon_timer, 0);

	timer_setup(&ifmgd->conn_mon_timer, ieee80211_sta_conn_mon_timer, 0);
@@ -7575,6 +7742,8 @@ void ieee80211_mgd_stop(struct ieee80211_sub_if_data *sdata) 
	wiphy_work_cancel(sdata->local->hw.wiphy,

			  &ifmgd->csa_connection_drop_work);

	cancel_delayed_work_sync(&ifmgd->tdls_peer_del_work);

	wiphy_delayed_work_cancel(sdata->local->hw.wiphy,

				  &ifmgd->ml_reconf_work);



	sdata_lock(sdata);

	if (ifmgd->assoc_data)