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 <ashok@cozybit.com>
Reviewed-by: Thomas Pedersen <thomas@cozybit.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
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 @@
}
rcu_read_unlock();
+
+ if (changed)
+ ieee80211_bss_info_change_notify(sdata, changed);
}