From f444de05d20e27cdd960c13fcbcfca3099f03143 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 5 May 2010 15:25:02 +0200 Subject: cfg80211/mac80211: better channel handling Currently (all tested with hwsim) you can do stupid things like setting up an AP on a certain channel, then adding another virtual interface and making that associate on another channel -- this will make the beaconing to move channel but obviously without the necessary IEs data update. In order to improve this situation, first make the configuration APIs (cfg80211 and nl80211) aware of multi-channel operation -- we'll eventually need that in the future anyway. There's one userland API change and one API addition. The API change is that now SET_WIPHY must be called with virtual interface index rather than only wiphy index in order to take effect for that interface -- luckily all current users (hostapd) do that. For monitor interfaces, the old setting is preserved, but monitors are always slaved to other devices anyway so no guarantees. The second userland API change is the introduction of a per virtual interface SET_CHANNEL command, that hostapd should use going forward to make it easier to understand what's going on (it can automatically detect a kernel with this command). Other than mac80211, no existing cfg80211 drivers are affected by this change because they only allow a single virtual interface. mac80211, however, now needs to be aware that the channel settings are per interface now, and needs to disallow (for now) real multi-channel operation, which is another important part of this patch. One of the immediate benefits is that you can now start hostapd to operate on a hardware that already has a connection on another virtual interface, as long as you specify the same channel. Note that two things are left unhandled (this is an improvement -- not a complete fix): * different HT/no-HT modes currently you could start an HT AP and then connect to a non-HT network on the same channel which would configure the hardware for no HT; that can be fixed fairly easily * CSA An AP we're connected to on a virtual interface might indicate switching channels, and in that case we would follow it, regardless of how many other interfaces are operating; this requires more effort to fix but is pretty rare after all Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- net/mac80211/ieee80211_i.h | 11 +++++++++++ 1 file changed, 11 insertions(+) (limited to 'net/mac80211/ieee80211_i.h') diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index c8077a3647c6..359edff31471 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -1229,6 +1229,17 @@ int ieee80211_wk_remain_on_channel(struct ieee80211_sub_if_data *sdata, int ieee80211_wk_cancel_remain_on_channel( struct ieee80211_sub_if_data *sdata, u64 cookie); +/* channel management */ +enum ieee80211_chan_mode { + CHAN_MODE_UNDEFINED, + CHAN_MODE_HOPPING, + CHAN_MODE_FIXED, +}; + +enum ieee80211_chan_mode +ieee80211_get_channel_mode(struct ieee80211_local *local, + struct ieee80211_sub_if_data *ignore); + #ifdef CONFIG_MAC80211_NOINLINE #define debug_noinline noinline #else -- cgit v1.2.3 From 0aaffa9b9699894aab3266195a529baf9f96ac29 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Wed, 5 May 2010 15:28:27 +0200 Subject: mac80211: improve HT channel handling Currently, when one interface switches HT mode, all others will follow along. This is clearly undesirable, since the new one might switch to no-HT while another one is operating in HT. Address this issue by keeping track of the HT mode per interface, and allowing only changes that are compatible, i.e. switching into HT40+ is not possible when another interface is in HT40-, in that case the second one needs to fall back to HT20. Also, to allow drivers to know what's going on, store the per-interface HT mode (channel type) in the virtual interface's bss_conf. Signed-off-by: Johannes Berg Signed-off-by: John W. Linville --- drivers/net/wireless/mac80211_hwsim.c | 19 +++++----- include/net/mac80211.h | 4 ++ net/mac80211/cfg.c | 23 +++++++++--- net/mac80211/chan.c | 70 +++++++++++++++++++++++++++++++++++ net/mac80211/ibss.c | 5 ++- net/mac80211/ieee80211_i.h | 5 ++- net/mac80211/main.c | 2 +- net/mac80211/mlme.c | 44 +++++++++++----------- 8 files changed, 132 insertions(+), 40 deletions(-) (limited to 'net/mac80211/ieee80211_i.h') diff --git a/drivers/net/wireless/mac80211_hwsim.c b/drivers/net/wireless/mac80211_hwsim.c index 62a739f6c37b..bdce71a4ba20 100644 --- a/drivers/net/wireless/mac80211_hwsim.c +++ b/drivers/net/wireless/mac80211_hwsim.c @@ -651,17 +651,17 @@ static void mac80211_hwsim_beacon(unsigned long arg) add_timer(&data->beacon_timer); } +static const char *hwsim_chantypes[] = { + [NL80211_CHAN_NO_HT] = "noht", + [NL80211_CHAN_HT20] = "ht20", + [NL80211_CHAN_HT40MINUS] = "ht40-", + [NL80211_CHAN_HT40PLUS] = "ht40+", +}; static int mac80211_hwsim_config(struct ieee80211_hw *hw, u32 changed) { struct mac80211_hwsim_data *data = hw->priv; struct ieee80211_conf *conf = &hw->conf; - static const char *chantypes[4] = { - [NL80211_CHAN_NO_HT] = "noht", - [NL80211_CHAN_HT20] = "ht20", - [NL80211_CHAN_HT40MINUS] = "ht40-", - [NL80211_CHAN_HT40PLUS] = "ht40+", - }; static const char *smps_modes[IEEE80211_SMPS_NUM_MODES] = { [IEEE80211_SMPS_AUTOMATIC] = "auto", [IEEE80211_SMPS_OFF] = "off", @@ -672,7 +672,7 @@ static int mac80211_hwsim_config(struct ieee80211_hw *hw, u32 changed) printk(KERN_DEBUG "%s:%s (freq=%d/%s idle=%d ps=%d smps=%s)\n", wiphy_name(hw->wiphy), __func__, conf->channel->center_freq, - chantypes[conf->channel_type], + hwsim_chantypes[conf->channel_type], !!(conf->flags & IEEE80211_CONF_IDLE), !!(conf->flags & IEEE80211_CONF_PS), smps_modes[conf->smps_mode]); @@ -760,9 +760,10 @@ static void mac80211_hwsim_bss_info_changed(struct ieee80211_hw *hw, } if (changed & BSS_CHANGED_HT) { - printk(KERN_DEBUG " %s: HT: op_mode=0x%x\n", + printk(KERN_DEBUG " %s: HT: op_mode=0x%x, chantype=%s\n", wiphy_name(hw->wiphy), - info->ht_operation_mode); + info->ht_operation_mode, + hwsim_chantypes[info->channel_type]); } if (changed & BSS_CHANGED_BASIC_RATES) { diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 0528615ac827..9448a5b1bb15 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -191,6 +191,9 @@ enum ieee80211_bss_change { * the current band. * @bssid: The BSSID for this BSS * @enable_beacon: whether beaconing should be enabled or not + * @channel_type: Channel type for this BSS -- the hardware might be + * configured for HT40+ while this BSS only uses no-HT, for + * example. * @ht_operation_mode: HT operation mode (like in &struct ieee80211_ht_info). * This field is only valid when the channel type is one of the HT types. * @cqm_rssi_thold: Connection quality monitor RSSI threshold, a zero value @@ -215,6 +218,7 @@ struct ieee80211_bss_conf { u16 ht_operation_mode; s32 cqm_rssi_thold; u32 cqm_rssi_hyst; + enum nl80211_channel_type channel_type; }; /** diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c index 414b7dd7d7fd..ab166c6d9399 100644 --- a/net/mac80211/cfg.c +++ b/net/mac80211/cfg.c @@ -1166,23 +1166,34 @@ static int ieee80211_set_channel(struct wiphy *wiphy, enum nl80211_channel_type channel_type) { struct ieee80211_local *local = wiphy_priv(wiphy); + struct ieee80211_sub_if_data *sdata = NULL; + + if (netdev) + sdata = IEEE80211_DEV_TO_SUB_IF(netdev); switch (ieee80211_get_channel_mode(local, NULL)) { case CHAN_MODE_HOPPING: return -EBUSY; case CHAN_MODE_FIXED: - if (local->oper_channel == chan && - local->oper_channel_type == channel_type) + if (local->oper_channel != chan) + return -EBUSY; + if (!sdata && local->_oper_channel_type == channel_type) return 0; - return -EBUSY; + break; case CHAN_MODE_UNDEFINED: break; } local->oper_channel = chan; - local->oper_channel_type = channel_type; - return ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + if (!ieee80211_set_channel_type(local, sdata, channel_type)) + return -EBUSY; + + ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); + if (sdata && sdata->vif.type != NL80211_IFTYPE_MONITOR) + ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_HT); + + return 0; } #ifdef CONFIG_PM @@ -1406,7 +1417,7 @@ int __ieee80211_request_smps(struct ieee80211_sub_if_data *sdata, * association, there's no need to send an action frame. */ if (!sdata->u.mgd.associated || - sdata->local->oper_channel_type == NL80211_CHAN_NO_HT) { + sdata->vif.bss_conf.channel_type == NL80211_CHAN_NO_HT) { mutex_lock(&sdata->local->iflist_mtx); ieee80211_recalc_smps(sdata->local, sdata); mutex_unlock(&sdata->local->iflist_mtx); diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c index 08f3832661a5..5d218c530a4e 100644 --- a/net/mac80211/chan.c +++ b/net/mac80211/chan.c @@ -2,6 +2,7 @@ * mac80211 - channel management */ +#include #include "ieee80211_i.h" enum ieee80211_chan_mode @@ -55,3 +56,72 @@ ieee80211_get_channel_mode(struct ieee80211_local *local, return mode; } + +bool ieee80211_set_channel_type(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata, + enum nl80211_channel_type chantype) +{ + struct ieee80211_sub_if_data *tmp; + enum nl80211_channel_type superchan = NL80211_CHAN_NO_HT; + bool result; + + mutex_lock(&local->iflist_mtx); + + list_for_each_entry(tmp, &local->interfaces, list) { + if (tmp == sdata) + continue; + + if (!ieee80211_sdata_running(tmp)) + continue; + + switch (tmp->vif.bss_conf.channel_type) { + case NL80211_CHAN_NO_HT: + case NL80211_CHAN_HT20: + superchan = tmp->vif.bss_conf.channel_type; + break; + case NL80211_CHAN_HT40PLUS: + WARN_ON(superchan == NL80211_CHAN_HT40MINUS); + superchan = NL80211_CHAN_HT40PLUS; + break; + case NL80211_CHAN_HT40MINUS: + WARN_ON(superchan == NL80211_CHAN_HT40PLUS); + superchan = NL80211_CHAN_HT40MINUS; + break; + } + } + + switch (superchan) { + case NL80211_CHAN_NO_HT: + case NL80211_CHAN_HT20: + /* + * allow any change that doesn't go to no-HT + * (if it already is no-HT no change is needed) + */ + if (chantype == NL80211_CHAN_NO_HT) + break; + superchan = chantype; + break; + case NL80211_CHAN_HT40PLUS: + case NL80211_CHAN_HT40MINUS: + /* allow smaller bandwidth and same */ + if (chantype == NL80211_CHAN_NO_HT) + break; + if (chantype == NL80211_CHAN_HT20) + break; + if (superchan == chantype) + break; + result = false; + goto out; + } + + local->_oper_channel_type = superchan; + + if (sdata) + sdata->vif.bss_conf.channel_type = chantype; + + result = true; + out: + mutex_unlock(&local->iflist_mtx); + + return result; +} diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c index d5855ae387e8..36745f494f63 100644 --- a/net/mac80211/ibss.c +++ b/net/mac80211/ibss.c @@ -102,7 +102,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata, sdata->drop_unencrypted = capability & WLAN_CAPABILITY_PRIVACY ? 1 : 0; local->oper_channel = chan; - local->oper_channel_type = NL80211_CHAN_NO_HT; + WARN_ON(!ieee80211_set_channel_type(local, sdata, NL80211_CHAN_NO_HT)); ieee80211_hw_config(local, IEEE80211_CONF_CHANGE_CHANNEL); sband = local->hw.wiphy->bands[chan->band]; @@ -910,7 +910,8 @@ int ieee80211_ibss_join(struct ieee80211_sub_if_data *sdata, /* fix ourselves to that channel now already */ if (params->channel_fixed) { sdata->local->oper_channel = params->channel; - sdata->local->oper_channel_type = NL80211_CHAN_NO_HT; + WARN_ON(!ieee80211_set_channel_type(sdata->local, sdata, + NL80211_CHAN_NO_HT)); } if (params->ie) { diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 359edff31471..69e7f4131f46 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -768,7 +768,7 @@ struct ieee80211_local { enum mac80211_scan_state next_scan_state; struct delayed_work scan_work; struct ieee80211_sub_if_data *scan_sdata; - enum nl80211_channel_type oper_channel_type; + enum nl80211_channel_type _oper_channel_type; struct ieee80211_channel *oper_channel, *csa_channel; /* Temporary remain-on-channel for off-channel operations */ @@ -1239,6 +1239,9 @@ enum ieee80211_chan_mode { enum ieee80211_chan_mode ieee80211_get_channel_mode(struct ieee80211_local *local, struct ieee80211_sub_if_data *ignore); +bool ieee80211_set_channel_type(struct ieee80211_local *local, + struct ieee80211_sub_if_data *sdata, + enum nl80211_channel_type chantype); #ifdef CONFIG_MAC80211_NOINLINE #define debug_noinline noinline diff --git a/net/mac80211/main.c b/net/mac80211/main.c index 353b6b42d9c5..d763d76e809f 100644 --- a/net/mac80211/main.c +++ b/net/mac80211/main.c @@ -111,7 +111,7 @@ int ieee80211_hw_config(struct ieee80211_local *local, u32 changed) channel_type = local->tmp_channel_type; } else { chan = local->oper_channel; - channel_type = local->oper_channel_type; + channel_type = local->_oper_channel_type; } if (chan != local->hw.conf.channel || diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c index 17cb8ae912bc..6e149b49d4f0 100644 --- a/net/mac80211/mlme.c +++ b/net/mac80211/mlme.c @@ -136,11 +136,14 @@ static u32 ieee80211_enable_ht(struct ieee80211_sub_if_data *sdata, struct sta_info *sta; u32 changed = 0; u16 ht_opmode; - bool enable_ht = true, ht_changed; + bool enable_ht = true; + enum nl80211_channel_type prev_chantype; enum nl80211_channel_type channel_type = NL80211_CHAN_NO_HT; sband = local->hw.wiphy->bands[local->hw.conf.channel->band]; + prev_chantype = sdata->vif.bss_conf.channel_type; + /* HT is not supported */ if (!sband->ht_cap.ht_supported) enable_ht = false; @@ -171,38 +174,37 @@ static u32 ieee80211_enable_ht(struct ieee80211_sub_if_data *sdata, } } - ht_changed = conf_is_ht(&local->hw.conf) != enable_ht || - channel_type != local->hw.conf.channel_type; - if (local->tmp_channel) local->tmp_channel_type = channel_type; - local->oper_channel_type = channel_type; - if (ht_changed) { - /* channel_type change automatically detected */ - ieee80211_hw_config(local, 0); + if (!ieee80211_set_channel_type(local, sdata, channel_type)) { + /* can only fail due to HT40+/- mismatch */ + channel_type = NL80211_CHAN_HT20; + WARN_ON(!ieee80211_set_channel_type(local, sdata, channel_type)); + } + /* channel_type change automatically detected */ + ieee80211_hw_config(local, 0); + + if (prev_chantype != channel_type) { rcu_read_lock(); sta = sta_info_get(sdata, bssid); if (sta) rate_control_rate_update(local, sband, sta, IEEE80211_RC_HT_CHANGED, - local->oper_channel_type); + channel_type); rcu_read_unlock(); - } - - /* disable HT */ - if (!enable_ht) - return 0; + } ht_opmode = le16_to_cpu(hti->operation_mode); /* if bss configuration changed store the new one */ - if (!sdata->ht_opmode_valid || - sdata->vif.bss_conf.ht_operation_mode != ht_opmode) { + if (sdata->ht_opmode_valid != enable_ht || + sdata->vif.bss_conf.ht_operation_mode != ht_opmode || + prev_chantype != channel_type) { changed |= BSS_CHANGED_HT; sdata->vif.bss_conf.ht_operation_mode = ht_opmode; - sdata->ht_opmode_valid = true; + sdata->ht_opmode_valid = enable_ht; } return changed; @@ -865,7 +867,7 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata, ieee80211_set_wmm_default(sdata); /* channel(_type) changes are handled by ieee80211_hw_config */ - local->oper_channel_type = NL80211_CHAN_NO_HT; + WARN_ON(!ieee80211_set_channel_type(local, sdata, NL80211_CHAN_NO_HT)); /* on the next assoc, re-program HT parameters */ sdata->ht_opmode_valid = false; @@ -882,8 +884,8 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata, ieee80211_hw_config(local, config_changed); - /* And the BSSID changed -- not very interesting here */ - changed |= BSS_CHANGED_BSSID; + /* The BSSID (not really interesting) and HT changed */ + changed |= BSS_CHANGED_BSSID | BSS_CHANGED_HT; ieee80211_bss_info_change_notify(sdata, changed); if (remove_sta) @@ -2265,7 +2267,7 @@ int ieee80211_mgd_action(struct ieee80211_sub_if_data *sdata, if ((chan != local->tmp_channel || channel_type != local->tmp_channel_type) && (chan != local->oper_channel || - channel_type != local->oper_channel_type)) + channel_type != local->_oper_channel_type)) return -EBUSY; skb = dev_alloc_skb(local->hw.extra_tx_headroom + len); -- cgit v1.2.3