From 57aac7c51c07ca7a2361477f352af422259301bd Mon Sep 17 00:00:00 2001 From: Ashok Nagarajan Date: Mon, 30 Apr 2012 14:20:30 -0700 Subject: [PATCH] mac80211: Implement HT mixed protection mode Section 9.23.3.5 of IEEE 80211s standard describes the protection rules for HT mesh STA in a MBSS. Three HT protection modes are supported for now: non-HT mixed mode - is selected if any non-HT peers are present in our MBSS. 20MHz-protection mode - is selected if all peers in our 20/40MHz MBSS support HT and atleast one HT20 peer is present. no-protection mode - is selected otherwise. This is a limited implementation of 9.23.3.5, which only considers mesh peers when determining the HT protection mode. Station's channel_type needs to be maintained. Signed-off-by: Ashok Nagarajan Reviewed-by: Thomas Pedersen Signed-off-by: John W. Linville --- net/mac80211/mesh_plink.c | 83 +++++++++++++++++++++++++++++++++++++++++++---- net/mac80211/sta_info.h | 1 + 2 files changed, 77 insertions(+), 7 deletions(-) diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c index 6209327..2e0ae73 100644 --- a/net/mac80211/mesh_plink.c +++ b/net/mac80211/mesh_plink.c @@ -105,6 +105,66 @@ static struct sta_info *mesh_plink_alloc(struct ieee80211_sub_if_data *sdata, return sta; } +/** mesh_set_ht_prot_mode - set correct HT protection mode + * + * Section 9.23.3.5 of IEEE 80211s standard describes the protection rules for + * HT mesh STA in a MBSS. Three HT protection modes are supported for now, + * non-HT mixed mode, 20MHz-protection and no-protection mode. non-HT mixed + * mode is selected if any non-HT peers are present in our MBSS. + * 20MHz-protection mode is selected if all peers in our 20/40MHz MBSS support + * HT and atleast one HT20 peer is present. Otherwise no-protection mode is + * selected. + */ +static u32 mesh_set_ht_prot_mode(struct ieee80211_sub_if_data *sdata) +{ + struct ieee80211_local *local = sdata->local; + struct sta_info *sta; + u32 changed = 0; + u16 ht_opmode; + bool non_ht_sta = false, ht20_sta = false; + + if (local->_oper_channel_type == NL80211_CHAN_NO_HT) + return 0; + + rcu_read_lock(); + list_for_each_entry_rcu(sta, &local->sta_list, list) { + if (sdata == sta->sdata && + sta->plink_state == NL80211_PLINK_ESTAB) { + switch (sta->ch_type) { + case NL80211_CHAN_NO_HT: + mpl_dbg("mesh_plink %pM: nonHT sta (%pM) is present", + sdata->vif.addr, sta->sta.addr); + non_ht_sta = true; + goto out; + case NL80211_CHAN_HT20: + mpl_dbg("mesh_plink %pM: HT20 sta (%pM) is present", + sdata->vif.addr, sta->sta.addr); + ht20_sta = true; + default: + break; + } + } + } +out: + rcu_read_unlock(); + + if (non_ht_sta) + ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONHT_MIXED; + else if (ht20_sta && local->_oper_channel_type > NL80211_CHAN_HT20) + ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_20MHZ; + else + ht_opmode = IEEE80211_HT_OP_MODE_PROTECTION_NONE; + + if (sdata->vif.bss_conf.ht_operation_mode != ht_opmode) { + sdata->vif.bss_conf.ht_operation_mode = ht_opmode; + changed = BSS_CHANGED_HT; + mpl_dbg("mesh_plink %pM: protection mode changed to %d", + sdata->vif.addr, ht_opmode); + } + + return changed; +} + /** * __mesh_plink_deactivate - deactivate mesh peer link * @@ -302,11 +362,14 @@ static struct sta_info *mesh_peer_init(struct ieee80211_sub_if_data *sdata, else memset(&sta->sta.ht_cap, 0, sizeof(sta->sta.ht_cap)); - if (elems->ht_operation) + if (elems->ht_operation) { if (!(elems->ht_operation->ht_param & IEEE80211_HT_PARAM_CHAN_WIDTH_ANY)) sta->sta.ht_cap.cap &= ~IEEE80211_HT_CAP_SUP_WIDTH_20_40; + sta->ch_type = + ieee80211_ht_oper_to_channel_type(elems->ht_operation); + } rate_control_rate_init(sta); spin_unlock_bh(&sta->lock); @@ -495,9 +558,10 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m enum plink_event event; enum ieee80211_self_protected_actioncode ftype; size_t baselen; - bool deactivated, matches_local = true; + bool matches_local = true; u8 ie_len; u8 *baseaddr; + u32 changed = 0; __le16 plid, llid, reason; #ifdef CONFIG_MAC80211_VERBOSE_MPL_DEBUG static const char *mplstates[] = { @@ -783,7 +847,8 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m sta->plink_state = NL80211_PLINK_ESTAB; spin_unlock_bh(&sta->lock); mesh_plink_inc_estab_count(sdata); - ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON); + changed |= mesh_set_ht_prot_mode(sdata); + changed |= BSS_CHANGED_BEACON; mpl_dbg("Mesh plink with %pM ESTABLISHED\n", sta->sta.addr); break; @@ -818,7 +883,8 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m sta->plink_state = NL80211_PLINK_ESTAB; spin_unlock_bh(&sta->lock); mesh_plink_inc_estab_count(sdata); - ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON); + changed |= mesh_set_ht_prot_mode(sdata); + changed |= BSS_CHANGED_BEACON; mpl_dbg("Mesh plink with %pM ESTABLISHED\n", sta->sta.addr); mesh_plink_frame_tx(sdata, @@ -836,13 +902,13 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m case CLS_ACPT: reason = cpu_to_le16(WLAN_REASON_MESH_CLOSE); sta->reason = reason; - deactivated = __mesh_plink_deactivate(sta); + __mesh_plink_deactivate(sta); sta->plink_state = NL80211_PLINK_HOLDING; llid = sta->llid; mod_plink_timer(sta, dot11MeshHoldingTimeout(sdata)); spin_unlock_bh(&sta->lock); - if (deactivated) - ieee80211_bss_info_change_notify(sdata, BSS_CHANGED_BEACON); + changed |= mesh_set_ht_prot_mode(sdata); + changed |= BSS_CHANGED_BEACON; mesh_plink_frame_tx(sdata, WLAN_SP_MESH_PEERING_CLOSE, sta->sta.addr, llid, plid, reason); break; @@ -889,4 +955,7 @@ void mesh_rx_plink_frame(struct ieee80211_sub_if_data *sdata, struct ieee80211_m } rcu_read_unlock(); + + if (changed) + ieee80211_bss_info_change_notify(sdata, changed); } diff --git a/net/mac80211/sta_info.h b/net/mac80211/sta_info.h index f75f5d9..663dc90 100644 --- a/net/mac80211/sta_info.h +++ b/net/mac80211/sta_info.h @@ -362,6 +362,7 @@ struct sta_info { struct timer_list plink_timer; s64 t_offset; s64 t_offset_setpoint; + enum nl80211_channel_type ch_type; #endif #ifdef CONFIG_MAC80211_DEBUGFS -- 2.7.4