[PATCH 1/3] cfg80211: consider VHT opmode on station update

[PATCH 1/3] cfg80211: consider VHT opmode on station update

[Johannes Berg]

From: Beni Lev <beni.lev@intel.com>

Currently, this attribute is only fetched on station addition, but
not on station change. Since this info is only present in the assoc
request, with full station state support in the driver it cannot be
present when the station is added.

Thus, add support for changing the VHT opmode on station update if
done before (or while) the station is marked as associated. After
this, ignore it, since it used to be ignored.

Signed-off-by: Beni Lev <beni.lev@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 include/uapi/linux/nl80211.h |  4 +++-
 net/wireless/nl80211.c       | 15 +++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 6b76e3b0c18e..bea982af9cfb 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1772,7 +1772,9 @@ enum nl80211_commands {
  *
  * @NL80211_ATTR_OPMODE_NOTIF: Operating mode field from Operating Mode
  *	Notification Element based on association request when used with
- *	%NL80211_CMD_NEW_STATION; u8 attribute.
+ *	%NL80211_CMD_NEW_STATION or %NL80211_CMD_SET_STATION (only when
+ *	%NL80211_FEATURE_FULL_AP_CLIENT_STATE is supported, or with TDLS);
+ *	u8 attribute.
  *
  * @NL80211_ATTR_VENDOR_ID: The vendor ID, either a 24-bit OUI or, if
  *	%NL80211_VENDOR_ID_IS_LINUX is set, a special Linux ID (not used yet)
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index ef5eff93a8b8..5c1b267e22be 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -4615,6 +4615,15 @@ int cfg80211_check_station_change(struct wiphy *wiphy,
 		break;
 	}
 
+	/*
+	 * Older kernel versions ignored this attribute entirely, so don't
+	 * reject attempts to update it but mark it as unused instead so the
+	 * driver won't look at the data.
+	 */
+	if (statype != CFG80211_STA_AP_CLIENT_UNASSOC &&
+	    statype != CFG80211_STA_TDLS_PEER_SETUP)
+		params->opmode_notif_used = false;
+
 	return 0;
 }
 EXPORT_SYMBOL(cfg80211_check_station_change);
@@ -4854,6 +4863,12 @@ static int nl80211_set_station(struct sk_buff *skb, struct genl_info *info)
 		params.local_pm = pm;
 	}
 
+	if (info->attrs[NL80211_ATTR_OPMODE_NOTIF]) {
+		params.opmode_notif_used = true;
+		params.opmode_notif =
+			nla_get_u8(info->attrs[NL80211_ATTR_OPMODE_NOTIF]);
+	}
+
 	/* Include parameters for TDLS peer (will check later) */
 	err = nl80211_set_station_tdls(info, &params);
 	if (err)
-- 
2.9.3

[PATCH 2/3] mac80211: calculate min channel width correctly

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

In the current minimum chandef code there's an issue in that the
recalculation can happen after rate control is initialized for a
station that has a wider bandwidth than the current chanctx, and
then rate control can immediately start using those higher rates
which could cause problems.

Observe that first of all that this problem is because we don't
take non-associated and non-uploaded stations into account. The
restriction to non-associated is quite pointless and is one of
the causes for the problem described above, since the rate init
will happen before the station is set to associated; no frames
could actually be sent until associated, but the rate table can
already contain higher rates and that might cause problems.

Also, rejecting non-uploaded stations is wrong, since the rate
control can select higher rates for those as well.

Secondly, it's then necessary to recalculate the minimal config
before initializing rate control, so that when rate control is
initialized, the higher rates are already available. This can be
done easily by adding the necessary function call in rate init.

Change-Id: Ib9bc02d34797078db55459d196993f39dcd43070
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/chan.c | 3 ---
 net/mac80211/rate.c | 2 ++
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index e75cbf6ecc26..a0d901d8992e 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -231,9 +231,6 @@ ieee80211_get_max_required_bw(struct ieee80211_sub_if_data *sdata)
 		    !(sta->sdata->bss && sta->sdata->bss == sdata->bss))
 			continue;
 
-		if (!sta->uploaded || !test_sta_flag(sta, WLAN_STA_ASSOC))
-			continue;
-
 		max_bw = max(max_bw, ieee80211_get_sta_bw(&sta->sta));
 	}
 	rcu_read_unlock();
diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
index 206698bc93f4..9e2641d45587 100644
--- a/net/mac80211/rate.c
+++ b/net/mac80211/rate.c
@@ -40,6 +40,8 @@ void rate_control_rate_init(struct sta_info *sta)
 
 	ieee80211_sta_set_rx_nss(sta);
 
+	ieee80211_recalc_min_chandef(sta->sdata);
+
 	if (!ref)
 		return;
 
-- 
2.9.3

[PATCH 3/3] mac80211: recalculate min channel width on VHT opmode changes

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

When an associated station changes its VHT operating mode this
can/will affect the bandwidth it's using, and consequently we
must recalculate the minimum bandwidth we need to use. Failure
to do so can lead to one of two scenarios:
 1) we use a too high bandwidth, this is benign
 2) we use a too narrow bandwidth, causing rate control and
    actual PHY configuration to be out of sync, which can in
    turn cause problems/crashes

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/iface.c | 21 +++++++++++++++++++++
 net/mac80211/rx.c    |  9 +--------
 net/mac80211/vht.c   |  4 +++-
 3 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 41497b670e2b..d37ae7dc114b 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -6,6 +6,7 @@
  * Copyright (c) 2006 Jiri Benc <jbenc@suse.cz>
  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
  * Copyright 2013-2014  Intel Mobile Communications GmbH
+ * Copyright (c) 2016        Intel Deutschland GmbH
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 2 as
@@ -1295,6 +1296,26 @@ static void ieee80211_iface_work(struct work_struct *work)
 		} else if (ieee80211_is_action(mgmt->frame_control) &&
 			   mgmt->u.action.category == WLAN_CATEGORY_VHT) {
 			switch (mgmt->u.action.u.vht_group_notif.action_code) {
+			case WLAN_VHT_ACTION_OPMODE_NOTIF: {
+				struct ieee80211_rx_status *status;
+				enum nl80211_band band;
+				u8 opmode;
+
+				status = IEEE80211_SKB_RXCB(skb);
+				band = status->band;
+				opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
+
+				mutex_lock(&local->sta_mtx);
+				sta = sta_info_get_bss(sdata, mgmt->sa);
+
+				if (sta)
+					ieee80211_vht_handle_opmode(sdata, sta,
+								    opmode,
+								    band);
+
+				mutex_unlock(&local->sta_mtx);
+				break;
+			}
 			case WLAN_VHT_ACTION_GROUPID_MGMT:
 				ieee80211_process_mu_groups(sdata, mgmt);
 				break;
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c
index c87e61358b77..3090dd4342f6 100644
--- a/net/mac80211/rx.c
+++ b/net/mac80211/rx.c
@@ -2881,17 +2881,10 @@ ieee80211_rx_h_action(struct ieee80211_rx_data *rx)
 
 		switch (mgmt->u.action.u.vht_opmode_notif.action_code) {
 		case WLAN_VHT_ACTION_OPMODE_NOTIF: {
-			u8 opmode;
-
 			/* verify opmode is present */
 			if (len < IEEE80211_MIN_ACTION_SIZE + 2)
 				goto invalid;
-
-			opmode = mgmt->u.action.u.vht_opmode_notif.operating_mode;
-
-			ieee80211_vht_handle_opmode(rx->sdata, rx->sta,
-						    opmode, status->band);
-			goto handled;
+			goto queue;
 		}
 		case WLAN_VHT_ACTION_GROUPID_MGMT: {
 			if (len < IEEE80211_MIN_ACTION_SIZE + 25)
diff --git a/net/mac80211/vht.c b/net/mac80211/vht.c
index 6832bf6ab69f..43e45bb660bc 100644
--- a/net/mac80211/vht.c
+++ b/net/mac80211/vht.c
@@ -527,8 +527,10 @@ void ieee80211_vht_handle_opmode(struct ieee80211_sub_if_data *sdata,
 
 	u32 changed = __ieee80211_vht_handle_opmode(sdata, sta, opmode, band);
 
-	if (changed > 0)
+	if (changed > 0) {
+		ieee80211_recalc_min_chandef(sdata);
 		rate_control_rate_update(local, sband, sta, changed);
+	}
 }
 
 void ieee80211_get_vht_mask_from_cap(__le16 vht_cap,
-- 
2.9.3