iwlwifi: mvm: include configured sniffer AID in radiotap

In order to make more sense out of the captured radiotap data e.g.
when the configured AID changes, add the currently configured AID
to the radiotap data as a vendor extension field.

This is made race-free by updating the included value from inside
the RX path (using a notification wait) for the command response
from the firmware, which thus means it's serialized with frame RX.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

1 files changed, 43 insertions, 1 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c b/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c
index 91b46361ac9f..e136475a34f6 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/debugfs.c
@@ -1682,11 +1682,33 @@ iwl_dbgfs_send_echo_cmd_write(struct iwl_mvm *mvm, char *buf,
 	return ret ?: count;
 }
 
+struct iwl_mvm_sniffer_apply {
+	struct iwl_mvm *mvm;
+	u16 aid;
+};
+
+static bool iwl_mvm_sniffer_apply(struct iwl_notif_wait_data *notif_data,
+				  struct iwl_rx_packet *pkt, void *data)
+{
+	struct iwl_mvm_sniffer_apply *apply = data;
+
+	apply->mvm->cur_aid = cpu_to_le16(apply->aid);
+
+	return true;
+}
+
 static ssize_t
 iwl_dbgfs_he_sniffer_params_write(struct iwl_mvm *mvm, char *buf,
-			size_t count, loff_t *ppos)
+				  size_t count, loff_t *ppos)
 {
+	struct iwl_notification_wait wait;
 	struct iwl_he_monitor_cmd he_mon_cmd = {};
+	struct iwl_mvm_sniffer_apply apply = {
+		.mvm = mvm,
+	};
+	u16 wait_cmds[] = {
+		iwl_cmd_id(HE_AIR_SNIFFER_CONFIG_CMD, DATA_PATH_GROUP, 0),
+	};
 	u32 aid;
 	int ret;
 
@@ -1702,10 +1724,30 @@ iwl_dbgfs_he_sniffer_params_write(struct iwl_mvm *mvm, char *buf,
 
 	he_mon_cmd.aid = cpu_to_le16(aid);
 
+	apply.aid = aid;
+
 	mutex_lock(&mvm->mutex);
+
+	/*
+	 * Use the notification waiter to get our function triggered
+	 * in sequence with other RX. This ensures that frames we get
+	 * on the RX queue _before_ the new configuration is applied
+	 * still have mvm->cur_aid pointing to the old AID, and that
+	 * frames on the RX queue _after_ the firmware processed the
+	 * new configuration (and sent the response, synchronously)
+	 * get mvm->cur_aid correctly set to the new AID.
+	 */
+	iwl_init_notification_wait(&mvm->notif_wait, &wait,
+				   wait_cmds, ARRAY_SIZE(wait_cmds),
+				   iwl_mvm_sniffer_apply, &apply);
+
 	ret = iwl_mvm_send_cmd_pdu(mvm, iwl_cmd_id(HE_AIR_SNIFFER_CONFIG_CMD,
 						   DATA_PATH_GROUP, 0), 0,
 				   sizeof(he_mon_cmd), &he_mon_cmd);
+
+	/* no need to really wait, we already did anyway */
+	iwl_remove_notification(&mvm->notif_wait, &wait);
+
 	mutex_unlock(&mvm->mutex);
 
 	return ret ?: count;