From 24398e39c8ee4a9d9123eed322b859ece4d16cac Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 28 Mar 2012 10:58:36 +0200 Subject: [PATCH] mac80211: set HT channel before association Changing the channel type during operation is confusing to some drivers and will be hard to handle in multi-channel scenarios. Instead of changing the channel, set it to the right HT channel before authenticating/associating and don't change it -- just update the 20/40 MHz restrictions in rate control as needed when changed by the AP. This also fixes a problem that Paul missed in his fix for the "regulatory makes us deaf" issue -- when we couldn't use 40 MHz we still associated saying we were using 40 MHz, which could in similarly broken APs make us never even connect successfully. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- .../networking/mac80211-auth-assoc-deauth.txt | 10 +- net/mac80211/ht.c | 9 - net/mac80211/ieee80211_i.h | 10 +- net/mac80211/mlme.c | 226 +++++++++--------- 4 files changed, 117 insertions(+), 138 deletions(-) diff --git a/Documentation/networking/mac80211-auth-assoc-deauth.txt b/Documentation/networking/mac80211-auth-assoc-deauth.txt index e0a2aa585ca..d7a15fe91bf 100644 --- a/Documentation/networking/mac80211-auth-assoc-deauth.txt +++ b/Documentation/networking/mac80211-auth-assoc-deauth.txt @@ -23,7 +23,7 @@ BA session stop & deauth/disassoc frames end note end -mac80211->driver: config(channel, non-HT) +mac80211->driver: config(channel, channel type) mac80211->driver: bss_info_changed(set BSSID, basic rate bitmap) mac80211->driver: sta_state(AP, exists) @@ -51,7 +51,7 @@ note over mac80211,driver: cleanup like for authenticate end alt not previously authenticated (FT) -mac80211->driver: config(channel, non-HT) +mac80211->driver: config(channel, channel type) mac80211->driver: bss_info_changed(set BSSID, basic rate bitmap) mac80211->driver: sta_state(AP, exists) mac80211->driver: sta_state(AP, authenticated) @@ -67,10 +67,6 @@ end mac80211->driver: set up QoS parameters -alt is HT channel -mac80211->driver: config(channel, HT params) -end - mac80211->driver: bss_info_changed(QoS, HT, associated with AID) mac80211->userspace: associated @@ -95,5 +91,5 @@ mac80211->driver: sta_state(AP,exists) mac80211->driver: sta_state(AP,not-exists) mac80211->driver: turn off powersave mac80211->driver: bss_info_changed(clear BSSID, not associated, no QoS, ...) -mac80211->driver: config(non-HT channel type) +mac80211->driver: config(channel type to non-HT) mac80211->userspace: disconnected diff --git a/net/mac80211/ht.c b/net/mac80211/ht.c index f25fff7607d..9b603366943 100644 --- a/net/mac80211/ht.c +++ b/net/mac80211/ht.c @@ -19,15 +19,6 @@ #include "ieee80211_i.h" #include "rate.h" -bool ieee80111_cfg_override_disables_ht40(struct ieee80211_sub_if_data *sdata) -{ - const __le16 flg = cpu_to_le16(IEEE80211_HT_CAP_SUP_WIDTH_20_40); - if ((sdata->u.mgd.ht_capa_mask.cap_info & flg) && - !(sdata->u.mgd.ht_capa.cap_info & flg)) - return true; - return false; -} - static void __check_htcap_disable(struct ieee80211_sub_if_data *sdata, struct ieee80211_sta_ht_cap *ht_cap, u16 flag) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 54f5b5b299d..a67ba7c85a1 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -379,6 +379,7 @@ enum ieee80211_sta_flags { IEEE80211_STA_UAPSD_ENABLED = BIT(7), IEEE80211_STA_NULLFUNC_ACKED = BIT(8), IEEE80211_STA_RESET_SIGNAL_AVE = BIT(9), + IEEE80211_STA_DISABLE_40MHZ = BIT(10), }; struct ieee80211_mgd_auth_data { @@ -511,6 +512,8 @@ struct ieee80211_if_managed { int rssi_min_thold, rssi_max_thold; int last_ave_beacon_signal; + enum nl80211_channel_type tx_chantype; + struct ieee80211_ht_cap ht_capa; /* configured ht-cap over-rides */ struct ieee80211_ht_cap ht_capa_mask; /* Valid parts of ht_capa */ }; @@ -667,12 +670,6 @@ struct ieee80211_sub_if_data { char name[IFNAMSIZ]; - /* - * keep track of whether the HT opmode (stored in - * vif.bss_info.ht_operation_mode) is valid. - */ - bool ht_opmode_valid; - /* to detect idle changes */ bool old_idle; @@ -1300,7 +1297,6 @@ netdev_tx_t ieee80211_subif_start_xmit(struct sk_buff *skb, struct net_device *dev); /* HT */ -bool ieee80111_cfg_override_disables_ht40(struct ieee80211_sub_if_data *sdata); void ieee80211_apply_htcap_overrides(struct ieee80211_sub_if_data *sdata, struct ieee80211_sta_ht_cap *ht_cap); void ieee80211_ht_cap_ie_to_sta_ht_cap(struct ieee80211_sub_if_data *sdata, diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index bb7e5189e27..30259a73195 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -171,110 +171,57 @@ static int ecw2cw(int ecw) return (1 << ecw) - 1; } -/* - * ieee80211_enable_ht should be called only after the operating band - * has been determined as ht configuration depends on the hw's - * HT abilities for a specific band. - */ -static u32 ieee80211_enable_ht(struct ieee80211_sub_if_data *sdata, - struct ieee80211_ht_operation *ht_oper, - const u8 *bssid, u16 ap_ht_cap_flags, - bool beacon_htcap_ie) +static u32 ieee80211_config_ht_tx(struct ieee80211_sub_if_data *sdata, + struct ieee80211_ht_operation *ht_oper, + const u8 *bssid, bool reconfig) { struct ieee80211_local *local = sdata->local; struct ieee80211_supported_band *sband; struct sta_info *sta; u32 changed = 0; - int ht_cfreq; u16 ht_opmode; - bool enable_ht = true; - enum nl80211_channel_type prev_chantype; - enum nl80211_channel_type rx_channel_type = NL80211_CHAN_NO_HT; - enum nl80211_channel_type tx_channel_type; + enum nl80211_channel_type channel_type; sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; - prev_chantype = sdata->vif.bss_conf.channel_type; + channel_type = local->hw.conf.channel_type; + if (WARN_ON_ONCE(channel_type == NL80211_CHAN_NO_HT)) + return 0; - ht_cfreq = ieee80211_channel_to_frequency(ht_oper->primary_chan, - sband->band); - /* check that channel matches the right operating channel */ - if (local->hw.conf.channel->center_freq != ht_cfreq) { - /* Some APs mess this up, evidently. - * Netgear WNDR3700 sometimes reports 4 higher than - * the actual channel, for instance. - */ - printk(KERN_DEBUG - "%s: Wrong control channel in association" - " response: configured center-freq: %d" - " ht-cfreq: %d ht->control_chan: %d" - " band: %d. Disabling HT.\n", - sdata->name, - local->hw.conf.channel->center_freq, - ht_cfreq, ht_oper->primary_chan, - sband->band); - enable_ht = false; - } - - if (enable_ht) { - rx_channel_type = NL80211_CHAN_HT20; - - if (!(ap_ht_cap_flags & IEEE80211_HT_CAP_40MHZ_INTOLERANT) && - !ieee80111_cfg_override_disables_ht40(sdata) && - (sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) && - (ht_oper->ht_param & IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) { - switch (ht_oper->ht_param & - IEEE80211_HT_PARAM_CHA_SEC_OFFSET) { - case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: - rx_channel_type = NL80211_CHAN_HT40PLUS; - break; - case IEEE80211_HT_PARAM_CHA_SEC_BELOW: - rx_channel_type = NL80211_CHAN_HT40MINUS; - break; - } - } - } - - tx_channel_type = ieee80211_get_tx_channel_type(local, rx_channel_type); - - if (local->tmp_channel) - local->tmp_channel_type = rx_channel_type; + channel_type = ieee80211_get_tx_channel_type(local, channel_type); - if (!ieee80211_set_channel_type(local, sdata, rx_channel_type)) { - /* can only fail due to HT40+/- mismatch */ - rx_channel_type = NL80211_CHAN_HT20; - WARN_ON(!ieee80211_set_channel_type(local, sdata, - rx_channel_type)); - } + /* This can change during the lifetime of the BSS */ + if (!(ht_oper->ht_param & IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) + channel_type = NL80211_CHAN_HT20; - if (beacon_htcap_ie && (prev_chantype != rx_channel_type)) { - /* - * Whenever the AP announces the HT mode change that can be - * 40MHz intolerant or etc., it would be safer to stop tx - * queues before doing hw config to avoid buffer overflow. - */ - ieee80211_stop_queues_by_reason(&sdata->local->hw, + if (!reconfig || (sdata->u.mgd.tx_chantype != channel_type)) { + if (reconfig) { + /* + * Whenever the AP announces the HT mode changed + * (e.g. 40 MHz intolerant) stop queues to avoid + * sending out frames while the rate control is + * reconfiguring. + */ + ieee80211_stop_queues_by_reason(&sdata->local->hw, IEEE80211_QUEUE_STOP_REASON_CHTYPE_CHANGE); - /* flush out all packets */ - synchronize_net(); - - drv_flush(local, false); - } + /* flush out all packets */ + synchronize_net(); - /* channel_type change automatically detected */ - ieee80211_hw_config(local, 0); + drv_flush(local, false); + } - if (prev_chantype != tx_channel_type) { rcu_read_lock(); sta = sta_info_get(sdata, bssid); if (sta) rate_control_rate_update(local, sband, sta, IEEE80211_RC_HT_CHANGED, - tx_channel_type); + channel_type); rcu_read_unlock(); - if (beacon_htcap_ie) + sdata->u.mgd.tx_chantype = channel_type; + + if (reconfig) ieee80211_wake_queues_by_reason(&sdata->local->hw, IEEE80211_QUEUE_STOP_REASON_CHTYPE_CHANGE); } @@ -282,12 +229,9 @@ static u32 ieee80211_enable_ht(struct ieee80211_sub_if_data *sdata, ht_opmode = le16_to_cpu(ht_oper->operation_mode); /* if bss configuration changed store the new one */ - if (sdata->ht_opmode_valid != enable_ht || - sdata->vif.bss_conf.ht_operation_mode != ht_opmode || - prev_chantype != rx_channel_type) { + if (!reconfig || (sdata->vif.bss_conf.ht_operation_mode != ht_opmode)) { changed |= BSS_CHANGED_HT; sdata->vif.bss_conf.ht_operation_mode = ht_opmode; - sdata->ht_opmode_valid = enable_ht; } return changed; @@ -359,6 +303,16 @@ static void ieee80211_add_ht_ie(struct ieee80211_sub_if_data *sdata, break; } + /* + * If 40 MHz was disabled associate as though we weren't + * capable of 40 MHz -- some broken APs will never fall + * back to trying to transmit in 20 MHz. + */ + if (sdata->u.mgd.flags & IEEE80211_STA_DISABLE_40MHZ) { + cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40; + cap &= ~IEEE80211_HT_CAP_SGI_40; + } + /* set SM PS mode properly */ cap &= ~IEEE80211_HT_CAP_SM_PS; switch (smps) { @@ -1436,7 +1390,6 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata, sdata->vif.bss_conf.assoc = false; /* on the next assoc, re-program HT parameters */ - sdata->ht_opmode_valid = false; memset(&ifmgd->ht_capa, 0, sizeof(ifmgd->ht_capa)); memset(&ifmgd->ht_capa_mask, 0, sizeof(ifmgd->ht_capa_mask)); @@ -2003,7 +1956,6 @@ static bool ieee80211_assoc_success(struct ieee80211_sub_if_data *sdata, struct ieee80211_bss_conf *bss_conf = &sdata->vif.bss_conf; u32 changed = 0; int err; - u16 ap_ht_cap_flags; /* AssocResp and ReassocResp have identical structure */ @@ -2054,8 +2006,6 @@ static bool ieee80211_assoc_success(struct ieee80211_sub_if_data *sdata, ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, elems.ht_cap_elem, &sta->sta.ht_cap); - ap_ht_cap_flags = sta->sta.ht_cap.cap; - rate_control_rate_init(sta); if (ifmgd->flags & IEEE80211_STA_MFP_ENABLED) @@ -2097,9 +2047,8 @@ static bool ieee80211_assoc_success(struct ieee80211_sub_if_data *sdata, if (elems.ht_operation && elems.wmm_param && !(ifmgd->flags & IEEE80211_STA_DISABLE_11N)) - changed |= ieee80211_enable_ht(sdata, elems.ht_operation, - cbss->bssid, ap_ht_cap_flags, - false); + changed |= ieee80211_config_ht_tx(sdata, elems.ht_operation, + cbss->bssid, false); /* set AID and assoc capability, * ieee80211_set_associated() will tell the driver */ @@ -2511,29 +2460,12 @@ static void ieee80211_rx_mgmt_beacon(struct ieee80211_sub_if_data *sdata, if (elems.ht_cap_elem && elems.ht_operation && elems.wmm_param && !(ifmgd->flags & IEEE80211_STA_DISABLE_11N)) { - struct sta_info *sta; struct ieee80211_supported_band *sband; - u16 ap_ht_cap_flags; - - rcu_read_lock(); - - sta = sta_info_get(sdata, bssid); - if (WARN_ON(!sta)) { - rcu_read_unlock(); - return; - } sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; - ieee80211_ht_cap_ie_to_sta_ht_cap(sdata, sband, - elems.ht_cap_elem, &sta->sta.ht_cap); - - ap_ht_cap_flags = sta->sta.ht_cap.cap; - - rcu_read_unlock(); - - changed |= ieee80211_enable_ht(sdata, elems.ht_operation, - bssid, ap_ht_cap_flags, true); + changed |= ieee80211_config_ht_tx(sdata, elems.ht_operation, + bssid, true); } /* Note: country IE parsing is done for us by cfg80211 */ @@ -3065,6 +2997,11 @@ static int ieee80211_prep_connection(struct ieee80211_sub_if_data *sdata, struct sta_info *sta; bool have_sta = false; int err; + int ht_cfreq; + enum nl80211_channel_type channel_type = NL80211_CHAN_NO_HT; + const u8 *ht_oper_ie; + const struct ieee80211_ht_operation *ht_oper = NULL; + struct ieee80211_supported_band *sband; if (WARN_ON(!ifmgd->auth_data && !ifmgd->assoc_data)) return -EINVAL; @@ -3086,17 +3023,76 @@ static int ieee80211_prep_connection(struct ieee80211_sub_if_data *sdata, mutex_unlock(&local->mtx); /* switch to the right channel */ + sband = local->hw.wiphy->bands[cbss->channel->band]; + + ifmgd->flags &= ~IEEE80211_STA_DISABLE_40MHZ; + + if (sband->ht_cap.ht_supported) { + ht_oper_ie = cfg80211_find_ie(WLAN_EID_HT_OPERATION, + cbss->information_elements, + cbss->len_information_elements); + if (ht_oper_ie && ht_oper_ie[1] >= sizeof(*ht_oper)) + ht_oper = (void *)(ht_oper_ie + 2); + } + + if (ht_oper) { + ht_cfreq = ieee80211_channel_to_frequency(ht_oper->primary_chan, + cbss->channel->band); + /* check that channel matches the right operating channel */ + if (cbss->channel->center_freq != ht_cfreq) { + /* + * It's possible that some APs are confused here; + * Netgear WNDR3700 sometimes reports 4 higher than + * the actual channel in association responses, but + * since we look at probe response/beacon data here + * it should be OK. + */ + printk(KERN_DEBUG + "%s: Wrong control channel: center-freq: %d" + " ht-cfreq: %d ht->primary_chan: %d" + " band: %d. Disabling HT.\n", + sdata->name, cbss->channel->center_freq, + ht_cfreq, ht_oper->primary_chan, + cbss->channel->band); + ht_oper = NULL; + } + } + + if (ht_oper) { + channel_type = NL80211_CHAN_HT20; + + if (sband->ht_cap.cap & IEEE80211_HT_CAP_SUP_WIDTH_20_40) { + switch (ht_oper->ht_param & + IEEE80211_HT_PARAM_CHA_SEC_OFFSET) { + case IEEE80211_HT_PARAM_CHA_SEC_ABOVE: + channel_type = NL80211_CHAN_HT40PLUS; + break; + case IEEE80211_HT_PARAM_CHA_SEC_BELOW: + channel_type = NL80211_CHAN_HT40MINUS; + break; + } + } + } + + if (!ieee80211_set_channel_type(local, sdata, channel_type)) { + /* can only fail due to HT40+/- mismatch */ + channel_type = NL80211_CHAN_HT20; + printk(KERN_DEBUG + "%s: disabling 40 MHz due to multi-vif mismatch\n", + sdata->name); + ifmgd->flags |= IEEE80211_STA_DISABLE_40MHZ; + WARN_ON(!ieee80211_set_channel_type(local, sdata, + channel_type)); + } + local->oper_channel = cbss->channel; - ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + ieee80211_hw_config(local, 0); if (!have_sta) { - struct ieee80211_supported_band *sband; u32 rates = 0, basic_rates = 0; bool have_higher_than_11mbit; int min_rate = INT_MAX, min_rate_index = -1; - sband = sdata->local->hw.wiphy->bands[cbss->channel->band]; - ieee80211_get_rates(sband, bss->supp_rates, bss->supp_rates_len, &rates, &basic_rates, -- 2.46.0