wifi: iwlwifi: mvm: Block EMLSR when a p2p/softAP vif is active

When there's an active link in a non-station vif, the station vif is
not allowed to enter EMLSR

Note that blocking EMLSR by calling iwl_mvm_block_esr() we will schedule
an exit from EMLSR worker, but the worker cannot run before the
activation of the non-BSS link, as ieee80211_remain_on_channel already
holds the wiphy mutex.

Handle that by explicitly calling ieee80211_set_active_links()
to leave EMLSR, and then doing iwl_mvm_block_esr() only for
consistency and to avoid re-entering it before ready.

Note that a call to ieee80211_set_active_links requires to release the
mvm mutex, but that's ok since we still hold the wiphy lock. The only
thing that might race here is the ESR_MODE_NOTIF, so this changes its
handler to run under the wiphy lock.

Signed-off-by: Yedidya Benshimol <yedidya.ben.shimol@intel.com>
Co-developed-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Link: https://msgid.link/20240505091420.916193759f8a.Idf3a3caf5cdc3e69c81710b7ceb57e87f2de87e4@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 85 insertions, 0 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/link.c b/drivers/net/wireless/intel/iwlwifi/mvm/link.c
index 7db4a834569c..7c8cfa72b8bb 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/link.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/link.c
@@ -108,6 +108,65 @@ int iwl_mvm_add_link(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 	return iwl_mvm_link_cmd_send(mvm, &cmd, FW_CTXT_ACTION_ADD);
 }
 
+struct iwl_mvm_esr_iter_data {
+	struct ieee80211_vif *vif;
+	unsigned int link_id;
+	bool lift_block;
+};
+
+static void iwl_mvm_esr_vif_iterator(void *_data, u8 *mac,
+				     struct ieee80211_vif *vif)
+{
+	struct iwl_mvm_esr_iter_data *data = _data;
+	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
+	int link_id;
+
+	if (ieee80211_vif_type_p2p(vif) == NL80211_IFTYPE_STATION)
+		return;
+
+	for_each_mvm_vif_valid_link(mvmvif, link_id) {
+		struct iwl_mvm_vif_link_info *link_info =
+			mvmvif->link[link_id];
+		if (vif == data->vif && link_id == data->link_id)
+			continue;
+		if (link_info->active)
+			data->lift_block = false;
+	}
+}
+
+int iwl_mvm_esr_non_bss_link(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
+			     unsigned int link_id, bool active)
+{
+	/* An active link of a non-station vif blocks EMLSR. Upon activation
+	 * block EMLSR on the bss vif. Upon deactivation, check if this link
+	 * was the last non-station link active, and if so unblock the bss vif
+	 */
+	struct ieee80211_vif *bss_vif = iwl_mvm_get_bss_vif(mvm);
+	struct iwl_mvm_esr_iter_data data = {
+		.vif = vif,
+		.link_id = link_id,
+		.lift_block = true,
+	};
+
+	if (IS_ERR_OR_NULL(bss_vif))
+		return 0;
+
+	if (active)
+		return iwl_mvm_block_esr_sync(mvm, bss_vif,
+					      IWL_MVM_ESR_BLOCKED_NON_BSS);
+
+	ieee80211_iterate_active_interfaces(mvm->hw,
+					    IEEE80211_IFACE_ITER_NORMAL,
+					    iwl_mvm_esr_vif_iterator, &data);
+	if (data.lift_block) {
+		mutex_lock(&mvm->mutex);
+		iwl_mvm_unblock_esr(mvm, bss_vif, IWL_MVM_ESR_BLOCKED_NON_BSS);
+		mutex_unlock(&mvm->mutex);
+	}
+
+	return 0;
+}
+
 int iwl_mvm_link_changed(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 			 struct ieee80211_bss_conf *link_conf,
 			 u32 changes, bool active)
@@ -924,6 +983,32 @@ void iwl_mvm_block_esr(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
 	iwl_mvm_exit_esr(mvm, vif, reason, link_to_keep);
 }
 
+int iwl_mvm_block_esr_sync(struct iwl_mvm *mvm, struct ieee80211_vif *vif,
+			   enum iwl_mvm_esr_state reason)
+{
+	int primary_link = iwl_mvm_get_primary_link(vif);
+	int ret;
+
+	if (!IWL_MVM_AUTO_EML_ENABLE || !ieee80211_vif_is_mld(vif))
+		return 0;
+
+	/* This should be called only with blocking reasons */
+	if (WARN_ON(!(reason & IWL_MVM_BLOCK_ESR_REASONS)))
+		return 0;
+
+	/* leave ESR immediately, not only async with iwl_mvm_block_esr() */
+	ret = ieee80211_set_active_links(vif, BIT(primary_link));
+	if (ret)
+		return ret;
+
+	mutex_lock(&mvm->mutex);
+	/* only additionally block for consistency and to avoid concurrency */
+	iwl_mvm_block_esr(mvm, vif, reason, primary_link);
+	mutex_unlock(&mvm->mutex);
+
+	return 0;
+}
+
 static void iwl_mvm_esr_unblocked(struct iwl_mvm *mvm,
 				  struct ieee80211_vif *vif)
 {