wifi: iwlwifi: mvm: Don't always bind/link the P2P Device interface

It is not necessary to keep the P2P Device bound/linked to a PHY
context when there is no active ROC.

Modify the P2P Device flows so the binding/linking would be done
only while ROC is active. With this change the switch_phy_ctxt()
is no longer needed so remove it.

Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20231004123422.c5b83b4bf9de.Ia80daf3ba0b5fec7d0919247fcbdbdb58bddf02b@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 48 insertions, 104 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
index 79ecfbb89c45..56945047e4f6 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/mac80211.c
@@ -1607,32 +1607,8 @@ static int iwl_mvm_mac_add_interface(struct ieee80211_hw *hw,
 				     IEEE80211_VIF_SUPPORTS_CQM_RSSI;
 	}
 
-	/*
-	 * P2P_DEVICE interface does not have a channel context assigned to it,
-	 * so a dedicated PHY context is allocated to it and the corresponding
-	 * MAC context is bound to it at this stage.
-	 */
-	if (vif->type == NL80211_IFTYPE_P2P_DEVICE) {
-
-		mvmvif->deflink.phy_ctxt = iwl_mvm_get_free_phy_ctxt(mvm);
-		if (!mvmvif->deflink.phy_ctxt) {
-			ret = -ENOSPC;
-			goto out_free_bf;
-		}
-
-		iwl_mvm_phy_ctxt_ref(mvm, mvmvif->deflink.phy_ctxt);
-		ret = iwl_mvm_binding_add_vif(mvm, vif);
-		if (ret)
-			goto out_unref_phy;
-
-		ret = iwl_mvm_add_p2p_bcast_sta(mvm, vif);
-		if (ret)
-			goto out_unbind;
-
-		/* Save a pointer to p2p device vif, so it can later be used to
-		 * update the p2p device MAC when a GO is started/stopped */
+	if (vif->type == NL80211_IFTYPE_P2P_DEVICE)
 		mvm->p2p_device_vif = vif;
-	}
 
 	iwl_mvm_tcm_add_vif(mvm, vif);
 	INIT_DELAYED_WORK(&mvmvif->csa_work,
@@ -1661,11 +1637,6 @@ out:
 
 	goto out_unlock;
 
- out_unbind:
-	iwl_mvm_binding_remove_vif(mvm, vif);
- out_unref_phy:
-	iwl_mvm_phy_ctxt_unref(mvm, mvmvif->deflink.phy_ctxt);
- out_free_bf:
 	if (mvm->bf_allowed_vif == mvmvif) {
 		mvm->bf_allowed_vif = NULL;
 		vif->driver_flags &= ~(IEEE80211_VIF_BEACON_FILTER |
@@ -1762,12 +1733,17 @@ static void iwl_mvm_mac_remove_interface(struct ieee80211_hw *hw,
 	if (iwl_mvm_mac_remove_interface_common(hw, vif))
 		goto out;
 
+	/* Before the interface removal, mac80211 would cancel the ROC, and the
+	 * ROC worker would be scheduled if needed. The worker would be flushed
+	 * in iwl_mvm_prepare_mac_removal() and thus at this point there is no
+	 * binding etc. so nothing needs to be done here.
+	 */
 	if (vif->type == NL80211_IFTYPE_P2P_DEVICE) {
+		if (mvmvif->deflink.phy_ctxt) {
+			iwl_mvm_phy_ctxt_unref(mvm, mvmvif->deflink.phy_ctxt);
+			mvmvif->deflink.phy_ctxt = NULL;
+		}
 		mvm->p2p_device_vif = NULL;
-		iwl_mvm_rm_p2p_bcast_sta(mvm, vif);
-		iwl_mvm_binding_remove_vif(mvm, vif);
-		iwl_mvm_phy_ctxt_unref(mvm, mvmvif->deflink.phy_ctxt);
-		mvmvif->deflink.phy_ctxt = NULL;
 	}
 
 	iwl_mvm_mac_ctxt_remove(mvm, vif);
@@ -4576,30 +4552,20 @@ static int iwl_mvm_add_aux_sta_for_hs20(struct iwl_mvm *mvm, u32 lmac_id)
 	return ret;
 }
 
-static int iwl_mvm_roc_switch_binding(struct iwl_mvm *mvm,
-				      struct ieee80211_vif *vif,
-				      struct iwl_mvm_phy_ctxt *new_phy_ctxt)
+static int iwl_mvm_roc_link(struct iwl_mvm *mvm, struct ieee80211_vif *vif)
 {
-	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
-	int ret = 0;
+	int ret;
 
 	lockdep_assert_held(&mvm->mutex);
 
-	/* Unbind the P2P_DEVICE from the current PHY context,
-	 * and if the PHY context is not used remove it.
-	 */
-	ret = iwl_mvm_binding_remove_vif(mvm, vif);
-	if (WARN(ret, "Failed unbinding P2P_DEVICE\n"))
+	ret = iwl_mvm_binding_add_vif(mvm, vif);
+	if (WARN(ret, "Failed binding P2P_DEVICE\n"))
 		return ret;
 
-	iwl_mvm_phy_ctxt_unref(mvm, mvmvif->deflink.phy_ctxt);
-
-	/* Bind the P2P_DEVICE to the current PHY Context */
-	mvmvif->deflink.phy_ctxt = new_phy_ctxt;
-
-	ret = iwl_mvm_binding_add_vif(mvm, vif);
-	WARN(ret, "Failed binding P2P_DEVICE\n");
-	return ret;
+	/* The station and queue allocation must be done only after the binding
+	 * is done, as otherwise the FW might incorrectly configure its state.
+	 */
+	return iwl_mvm_add_p2p_bcast_sta(mvm, vif);
 }
 
 static int iwl_mvm_roc(struct ieee80211_hw *hw,
@@ -4610,7 +4576,7 @@ static int iwl_mvm_roc(struct ieee80211_hw *hw,
 {
 	static const struct iwl_mvm_roc_ops ops = {
 		.add_aux_sta_for_hs20 = iwl_mvm_add_aux_sta_for_hs20,
-		.switch_phy_ctxt = iwl_mvm_roc_switch_binding,
+		.link = iwl_mvm_roc_link,
 	};
 
 	return iwl_mvm_roc_common(hw, vif, channel, duration, type, &ops);
@@ -4626,7 +4592,6 @@ int iwl_mvm_roc_common(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 	struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
 	struct cfg80211_chan_def chandef;
 	struct iwl_mvm_phy_ctxt *phy_ctxt;
-	bool band_change_removal;
 	int ret, i;
 	u32 lmac_id;
 
@@ -4655,82 +4620,61 @@ int iwl_mvm_roc_common(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
 		/* handle below */
 		break;
 	default:
-		IWL_ERR(mvm, "vif isn't P2P_DEVICE: %d\n", vif->type);
+		IWL_ERR(mvm, "ROC: Invalid vif type=%u\n", vif->type);
 		ret = -EINVAL;
 		goto out_unlock;
 	}
 
+	/* Try using a PHY context that is already in use */
 	for (i = 0; i < NUM_PHY_CTX; i++) {
 		phy_ctxt = &mvm->phy_ctxts[i];
-		if (phy_ctxt->ref == 0 || mvmvif->deflink.phy_ctxt == phy_ctxt)
+		if (!phy_ctxt->ref || mvmvif->deflink.phy_ctxt == phy_ctxt)
 			continue;
 
-		if (phy_ctxt->ref && channel == phy_ctxt->channel) {
-			ret = ops->switch_phy_ctxt(mvm, vif, phy_ctxt);
-			if (ret)
-				goto out_unlock;
+		if (channel == phy_ctxt->channel) {
+			if (mvmvif->deflink.phy_ctxt)
+				iwl_mvm_phy_ctxt_unref(mvm,
+						       mvmvif->deflink.phy_ctxt);
 
+			mvmvif->deflink.phy_ctxt = phy_ctxt;
 			iwl_mvm_phy_ctxt_ref(mvm, mvmvif->deflink.phy_ctxt);
-			goto schedule_time_event;
+			goto link_and_start_p2p_roc;
 		}
 	}
 
-	/* Need to update the PHY context only if the ROC channel changed */
-	if (channel == mvmvif->deflink.phy_ctxt->channel)
-		goto schedule_time_event;
-
-	cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
-
-	/*
-	 * Check if the remain-on-channel is on a different band and that
-	 * requires context removal, see iwl_mvm_phy_ctxt_changed(). If
-	 * so, we'll need to release and then re-configure here, since we
-	 * must not remove a PHY context that's part of a binding.
+	/* If the currently used PHY context is configured with a matching
+	 * channel use it
 	 */
-	band_change_removal =
-		fw_has_capa(&mvm->fw->ucode_capa,
-			    IWL_UCODE_TLV_CAPA_BINDING_CDB_SUPPORT) &&
-		mvmvif->deflink.phy_ctxt->channel->band != chandef.chan->band;
-
-	if (mvmvif->deflink.phy_ctxt->ref == 1 && !band_change_removal) {
-		/*
-		 * Change the PHY context configuration as it is currently
-		 * referenced only by the P2P Device MAC (and we can modify it)
-		 */
-		ret = iwl_mvm_phy_ctxt_changed(mvm, mvmvif->deflink.phy_ctxt,
-					       &chandef, 1, 1);
-		if (ret)
-			goto out_unlock;
+	if (mvmvif->deflink.phy_ctxt) {
+		if (channel == mvmvif->deflink.phy_ctxt->channel)
+			goto link_and_start_p2p_roc;
 	} else {
-		/*
-		 * The PHY context is shared with other MACs (or we're trying to
-		 * switch bands), so remove the P2P Device from the binding,
-		 * allocate an new PHY context and create a new binding.
-		 */
 		phy_ctxt = iwl_mvm_get_free_phy_ctxt(mvm);
 		if (!phy_ctxt) {
 			ret = -ENOSPC;
 			goto out_unlock;
 		}
 
-		ret = iwl_mvm_phy_ctxt_changed(mvm, phy_ctxt, &chandef,
-					       1, 1);
-		if (ret) {
-			IWL_ERR(mvm, "Failed to change PHY context\n");
-			goto out_unlock;
-		}
+		mvmvif->deflink.phy_ctxt = phy_ctxt;
+		iwl_mvm_phy_ctxt_ref(mvm, mvmvif->deflink.phy_ctxt);
+	}
 
-		ret = ops->switch_phy_ctxt(mvm, vif, phy_ctxt);
-		if (ret)
-			goto out_unlock;
+	/* Configure the PHY context */
+	cfg80211_chandef_create(&chandef, channel, NL80211_CHAN_NO_HT);
 
-		iwl_mvm_phy_ctxt_ref(mvm, mvmvif->deflink.phy_ctxt);
+	ret = iwl_mvm_phy_ctxt_changed(mvm, phy_ctxt, &chandef,
+				       1, 1);
+	if (ret) {
+		IWL_ERR(mvm, "Failed to change PHY context\n");
+		goto out_unlock;
 	}
 
-schedule_time_event:
-	/* Schedule the time events */
-	ret = iwl_mvm_start_p2p_roc(mvm, vif, duration, type);
+link_and_start_p2p_roc:
+	ret = ops->link(mvm, vif);
+	if (ret)
+		goto out_unlock;
 
+	ret = iwl_mvm_start_p2p_roc(mvm, vif, duration, type);
 out_unlock:
 	mutex_unlock(&mvm->mutex);
 	IWL_DEBUG_MAC80211(mvm, "leave\n");