wifi: mac80211: add link id to mgd_prepare_tx()

As we are moving to MLO and links terms, also the airtime protection
will be done for a link rather than for a vif. Thus, some
drivers will need to know for which link to protect airtime.
Add link id as a parameter to the mgd_prepare_tx() callback.
Signed-off-by: Miri Korenblit <miriam.rachel.korenblit@intel.com>
Signed-off-by: Gregory Greenman <gregory.greenman@intel.com>
Link: https://lore.kernel.org/r/20230928172905.c7fc59a6780b.Ic88a5037d31e184a2dce0b031ece1a0a93a3a9da@changeidSigned-off-by: Johannes Berg <johannes.berg@intel.com>

include/net/mac80211.h

@@ -3641,11 +3641,14 @@ enum ieee80211_reconfig_type {
  * @success: whether the frame exchange was successful, only
  *	used with the mgd_complete_tx() method, and then only
  *	valid for auth and (re)assoc.
+ * @link_id: the link id on which the frame will be TX'ed.
+ *	Only used with the mgd_prepare_tx() method.
  */
 struct ieee80211_prep_tx_info {
 	u16 duration;
 	u16 subtype;
 	u8 success:1;
+	int link_id;
 };
 
 /**

net/mac80211/driver-ops.h

@@ -928,6 +928,7 @@ static inline void drv_mgd_prepare_tx(struct ieee80211_local *local,
 		return;
 	WARN_ON_ONCE(sdata->vif.type != NL80211_IFTYPE_STATION);
 
+	info->link_id = info->link_id < 0 ? 0 : info->link_id;
 	trace_drv_mgd_prepare_tx(local, sdata, info->duration,
 				 info->subtype, info->success);
 	if (local->ops->mgd_prepare_tx)

net/mac80211/mlme.c

@@ -1584,6 +1584,7 @@ static int ieee80211_send_assoc(struct ieee80211_sub_if_data *sdata)
 
 	ifmgd->assoc_req_ies_len = pos - ie_start;
 
+	info.link_id = assoc_data->assoc_link_id;
 	drv_mgd_prepare_tx(local, sdata, &info);
 
 	IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
@@ -2948,8 +2949,10 @@ static void ieee80211_set_disassoc(struct ieee80211_sub_if_data *sdata,
 				if (link->u.mgd.have_beacon)
 					break;
 			}
-			if (link_id == IEEE80211_MLD_MAX_NUM_LINKS)
+			if (link_id == IEEE80211_MLD_MAX_NUM_LINKS) {
+				info.link_id = ffs(sdata->vif.active_links) - 1;
 				drv_mgd_prepare_tx(sdata->local, sdata, &info);
+			}
 		}
 
 		ieee80211_send_deauth_disassoc(sdata, sdata->vif.cfg.ap_addr,
@@ -3577,6 +3580,7 @@ static void ieee80211_auth_challenge(struct ieee80211_sub_if_data *sdata,
 	u32 tx_flags = 0;
 	struct ieee80211_prep_tx_info info = {
 		.subtype = IEEE80211_STYPE_AUTH,
+		.link_id = auth_data->link_id,
 	};
 
 	pos = mgmt->u.auth.variable;
@@ -6569,6 +6573,7 @@ static int ieee80211_auth(struct ieee80211_sub_if_data *sdata)
 	if (auth_data->algorithm == WLAN_AUTH_SAE)
 		info.duration = jiffies_to_msecs(IEEE80211_AUTH_TIMEOUT_SAE);
 
+	info.link_id = auth_data->link_id;
 	drv_mgd_prepare_tx(local, sdata, &info);
 
 	sdata_info(sdata, "send auth to %pM (try %d/%d)\n",
@@ -7989,6 +7994,7 @@ int ieee80211_mgd_deauth(struct ieee80211_sub_if_data *sdata,
 			   req->bssid, req->reason_code,
 			   ieee80211_get_reason_code_string(req->reason_code));
 
+		info.link_id = ifmgd->auth_data->link_id;
 		drv_mgd_prepare_tx(sdata->local, sdata, &info);
 		ieee80211_send_deauth_disassoc(sdata, req->bssid, req->bssid,
 					       IEEE80211_STYPE_DEAUTH,
@@ -8009,6 +8015,7 @@ int ieee80211_mgd_deauth(struct ieee80211_sub_if_data *sdata,
 			   req->bssid, req->reason_code,
 			   ieee80211_get_reason_code_string(req->reason_code));
 
+		info.link_id = ifmgd->assoc_data->assoc_link_id;
 		drv_mgd_prepare_tx(sdata->local, sdata, &info);
 		ieee80211_send_deauth_disassoc(sdata, req->bssid, req->bssid,
 					       IEEE80211_STYPE_DEAUTH,