An AP/GO may perform the channel switch slightly before its stations.
This scenario may result in packet loss, since the transmission may start
before the client is actually on a new channel. In order to prevent
potential packet loss disable tx to all the stations when the channel
switch flow starts. Clear the disable_tx bit when a station is seen on a
target channel, or after IWL_MVM_CS_UNBLOCK_TX_TIMEOUT beacons on a new
channel. In addition call ieee80211_sta_block_awake in order to inform
mac80211 that the frames for this station should be buffered.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Reviewed-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
struct iwl_rx_packet *pkt = rxb_addr(rxb);
struct iwl_mvm_tx_resp *beacon_notify_hdr;
struct ieee80211_vif *csa_vif;
+ struct ieee80211_vif *tx_blocked_vif;
u64 tsf;
lockdep_assert_held(&mvm->mutex);
if (unlikely(csa_vif && csa_vif->csa_active))
iwl_mvm_csa_count_down(mvm, csa_vif, mvm->ap_last_beacon_gp2);
+ tx_blocked_vif = rcu_dereference_protected(mvm->csa_tx_blocked_vif,
+ lockdep_is_held(&mvm->mutex));
+ if (unlikely(tx_blocked_vif)) {
+ struct iwl_mvm_vif *mvmvif =
+ iwl_mvm_vif_from_mac80211(tx_blocked_vif);
+
+ /*
+ * The channel switch is started and we have blocked the
+ * stations. If this is the first beacon (the timeout wasn't
+ * set), set the unblock timeout, otherwise countdown
+ */
+ if (!mvm->csa_tx_block_bcn_timeout)
+ mvm->csa_tx_block_bcn_timeout =
+ IWL_MVM_CS_UNBLOCK_TX_TIMEOUT;
+ else
+ mvm->csa_tx_block_bcn_timeout--;
+
+ /* Check if the timeout is expired, and unblock tx */
+ if (mvm->csa_tx_block_bcn_timeout == 0) {
+ iwl_mvm_modify_all_sta_disable_tx(mvm, mvmvif, false);
+ RCU_INIT_POINTER(mvm->csa_tx_blocked_vif, NULL);
+ }
+ }
+
return 0;
}
RCU_INIT_POINTER(mvm->csa_vif, NULL);
}
+ if (rcu_access_pointer(mvm->csa_tx_blocked_vif) == vif) {
+ RCU_INIT_POINTER(mvm->csa_tx_blocked_vif, NULL);
+ mvm->csa_tx_block_bcn_timeout = 0;
+ }
+
mvmvif->ap_ibss_active = false;
mvm->ap_last_beacon_gp2 = 0;
if (!vif->csa_active || !mvmvif->ap_ibss_active)
goto out;
+ /* Set CS bit on all the stations */
+ iwl_mvm_modify_all_sta_disable_tx(mvm, mvmvif, true);
+
+ /* Save blocked iface, the timeout is set on the next beacon */
+ rcu_assign_pointer(mvm->csa_tx_blocked_vif, vif);
+
mvmvif->ap_ibss_active = false;
break;
case NL80211_IFTYPE_STATION:
*/
#define IWL_MVM_CHANNEL_SWITCH_MARGIN 4
+/*
+ * Number of beacons to transmit on a new channel until we unblock tx to
+ * the stations, even if we didn't identify them on a new channel
+ */
+#define IWL_MVM_CS_UNBLOCK_TX_TIMEOUT 3
+
enum iwl_mvm_tx_fifo {
IWL_MVM_TX_FIFO_BK = 0,
IWL_MVM_TX_FIFO_BE,
bool ps_disabled;
struct ieee80211_vif __rcu *csa_vif;
+ struct ieee80211_vif __rcu *csa_tx_blocked_vif;
+ u8 csa_tx_block_bcn_timeout;
/* system time of last beacon (for AP/GO interface) */
u32 ap_last_beacon_gp2;
memset(&rx_status, 0, sizeof(rx_status));
+ /*
+ * We have tx blocked stations (with CS bit). If we heard frames from
+ * a blocked station on a new channel we can TX to it again.
+ */
+ if (unlikely(mvm->csa_tx_block_bcn_timeout)) {
+ struct ieee80211_sta *sta;
+
+ rcu_read_lock();
+
+ sta = ieee80211_find_sta(
+ rcu_dereference(mvm->csa_tx_blocked_vif), hdr->addr2);
+ if (sta)
+ iwl_mvm_sta_modify_disable_tx_ap(mvm, sta, false);
+
+ rcu_read_unlock();
+ }
+
/*
* drop the packet if it has failed being decrypted by HW
*/
if (ret)
IWL_ERR(mvm, "Failed to send ADD_STA command (%d)\n", ret);
}
+
+void iwl_mvm_sta_modify_disable_tx_ap(struct iwl_mvm *mvm,
+ struct ieee80211_sta *sta,
+ bool disable)
+{
+ struct iwl_mvm_sta *mvm_sta = iwl_mvm_sta_from_mac80211(sta);
+
+ spin_lock_bh(&mvm_sta->lock);
+
+ if (mvm_sta->disable_tx == disable) {
+ spin_unlock_bh(&mvm_sta->lock);
+ return;
+ }
+
+ mvm_sta->disable_tx = disable;
+
+ /*
+ * Tell mac80211 to start/stop queueing tx for this station,
+ * but don't stop queueing if there are still pending frames
+ * for this station.
+ */
+ if (disable || !atomic_read(&mvm->pending_frames[mvm_sta->sta_id]))
+ ieee80211_sta_block_awake(mvm->hw, sta, disable);
+
+ iwl_mvm_sta_modify_disable_tx(mvm, mvm_sta, disable);
+
+ spin_unlock_bh(&mvm_sta->lock);
+}
+
+void iwl_mvm_modify_all_sta_disable_tx(struct iwl_mvm *mvm,
+ struct iwl_mvm_vif *mvmvif,
+ bool disable)
+{
+ struct ieee80211_sta *sta;
+ struct iwl_mvm_sta *mvm_sta;
+ int i;
+
+ lockdep_assert_held(&mvm->mutex);
+
+ /* Block/unblock all the stations of the given mvmvif */
+ for (i = 0; i < IWL_MVM_STATION_COUNT; i++) {
+ sta = rcu_dereference_protected(mvm->fw_id_to_mac_id[i],
+ lockdep_is_held(&mvm->mutex));
+ if (IS_ERR_OR_NULL(sta))
+ continue;
+
+ mvm_sta = iwl_mvm_sta_from_mac80211(sta);
+ if (mvm_sta->mac_id_n_color !=
+ FW_CMD_ID_AND_COLOR(mvmvif->id, mvmvif->color))
+ continue;
+
+ iwl_mvm_sta_modify_disable_tx_ap(mvm, sta, disable);
+ }
+}
#include "rs.h"
struct iwl_mvm;
+struct iwl_mvm_vif;
/**
* DOC: station table - introduction
* @tid_data: per tid data. Look at %iwl_mvm_tid_data.
* @tx_protection: reference counter for controlling the Tx protection.
* @tt_tx_protection: is thermal throttling enable Tx protection?
+ * @disable_tx: is tx to this STA disabled?
*
* When mac80211 creates a station it reserves some space (hw->sta_data_size)
* in the structure for use by driver. This structure is placed in that
/* Temporary, until the new TLC will control the Tx protection */
s8 tx_protection;
bool tt_tx_protection;
+
+ bool disable_tx;
};
static inline struct iwl_mvm_sta *
bool drain);
void iwl_mvm_sta_modify_disable_tx(struct iwl_mvm *mvm,
struct iwl_mvm_sta *mvmsta, bool disable);
+void iwl_mvm_sta_modify_disable_tx_ap(struct iwl_mvm *mvm,
+ struct ieee80211_sta *sta,
+ bool disable);
+void iwl_mvm_modify_all_sta_disable_tx(struct iwl_mvm *mvm,
+ struct iwl_mvm_vif *mvmvif,
+ bool disable);
#endif /* __sta_h__ */
goto out;
if (mvmsta && mvmsta->vif->type == NL80211_IFTYPE_AP) {
+
/*
- * If there are no pending frames for this STA, notify
- * mac80211 that this station can go to sleep in its
+ * If there are no pending frames for this STA and
+ * the tx to this station is not disabled, notify
+ * mac80211 that this station can now wake up in its
* STA table.
* If mvmsta is not NULL, sta is valid.
*/
- ieee80211_sta_block_awake(mvm->hw, sta, false);
+
+ spin_lock_bh(&mvmsta->lock);
+
+ if (!mvmsta->disable_tx)
+ ieee80211_sta_block_awake(mvm->hw, sta, false);
+
+ spin_unlock_bh(&mvmsta->lock);
}
if (PTR_ERR(sta) == -EBUSY || PTR_ERR(sta) == -ENOENT) {
projects / ~emulex / infiniband.git / commitdiff