wifi: mac80211: move code in ieee80211_link_reserve_chanctx to a helper

Reduces indentation in preparation for further changes
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://patch.msgid.link/cce95007092336254d51570f4a27e05a6f150a53.1720514221.git-series.nbd@nbd.nameSigned-off-by: Johannes Berg <johannes.berg@intel.com>

net/mac80211/chan.c

@@ -1089,57 +1089,35 @@ int ieee80211_link_unreserve_chanctx(struct ieee80211_link_data *link)
 	return 0;
 }
 
-int ieee80211_link_reserve_chanctx(struct ieee80211_link_data *link,
+static struct ieee80211_chanctx *
+ieee80211_replace_chanctx(struct ieee80211_local *local,
 			  const struct ieee80211_chan_req *chanreq,
 			  enum ieee80211_chanctx_mode mode,
-				   bool radar_required)
+			  struct ieee80211_chanctx *curr_ctx)
 {
-	struct ieee80211_sub_if_data *sdata = link->sdata;
-	struct ieee80211_local *local = sdata->local;
-	struct ieee80211_chanctx *new_ctx, *curr_ctx, *ctx;
-
-	lockdep_assert_wiphy(local->hw.wiphy);
-
-	curr_ctx = ieee80211_link_get_chanctx(link);
-	if (curr_ctx && !local->ops->switch_vif_chanctx)
-		return -EOPNOTSUPP;
+	struct ieee80211_chanctx *new_ctx, *ctx;
 
-	new_ctx = ieee80211_find_reservation_chanctx(local, chanreq, mode);
-	if (!new_ctx) {
-		if (ieee80211_can_create_new_chanctx(local, -1)) {
-			new_ctx = ieee80211_new_chanctx(local, chanreq, mode,
-							false);
-			if (IS_ERR(new_ctx))
-				return PTR_ERR(new_ctx);
-		} else {
-			if (!curr_ctx ||
-			    (curr_ctx->replace_state ==
+	if (!curr_ctx || (curr_ctx->replace_state ==
 			  IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 	    !list_empty(&curr_ctx->reserved_links)) {
 		/*
-				 * Another link already requested this context
-				 * for a reservation. Find another one hoping
-				 * all links assigned to it will also switch
-				 * soon enough.
+		 * Another link already requested this context for a
+		 * reservation. Find another one hoping all links assigned
+		 * to it will also switch soon enough.
 		 *
-				 * TODO: This needs a little more work as some
-				 * cases (more than 2 chanctx capable devices)
-				 * may fail which could otherwise succeed
-				 * provided some channel context juggling was
+		 * TODO: This needs a little more work as some cases
+		 * (more than 2 chanctx capable devices) may fail which could
+		 * otherwise succeed provided some channel context juggling was
 		 * performed.
 		 *
-				 * Consider ctx1..3, link1..6, each ctx has 2
-				 * links. link1 and link2 from ctx1 request new
-				 * different chandefs starting 2 in-place
-				 * reserations with ctx4 and ctx5 replacing
-				 * ctx1 and ctx2 respectively. Next link5 and
-				 * link6 from ctx3 reserve ctx4. If link3 and
-				 * link4 remain on ctx2 as they are then this
-				 * fails unless `replace_ctx` from ctx5 is
-				 * replaced with ctx3.
+		 * Consider ctx1..3, link1..6, each ctx has 2 links. link1 and
+		 * link2 from ctx1 request new different chandefs starting 2
+		 * in-place reserations with ctx4 and ctx5 replacing ctx1 and
+		 * ctx2 respectively. Next link5 and link6 from ctx3 reserve
+		 * ctx4. If link3 and link4 remain on ctx2 as they are then this
+		 * fails unless `replace_ctx` from ctx5 is replaced with ctx3.
 		 */
-				list_for_each_entry(ctx, &local->chanctx_list,
-						    list) {
+		list_for_each_entry(ctx, &local->chanctx_list, list) {
 			if (ctx->replace_state !=
 			    IEEE80211_CHANCTX_REPLACE_NONE)
 				continue;
@@ -1153,29 +1131,54 @@ int ieee80211_link_reserve_chanctx(struct ieee80211_link_data *link,
 	}
 
 	/*
-			 * If that's true then all available contexts already
-			 * have reservations and cannot be used.
+	 * If that's true then all available contexts already have reservations
+	 * and cannot be used.
 	 */
-			if (!curr_ctx ||
-			    (curr_ctx->replace_state ==
+	if (!curr_ctx || (curr_ctx->replace_state ==
 			  IEEE80211_CHANCTX_WILL_BE_REPLACED) ||
 	    !list_empty(&curr_ctx->reserved_links))
-				return -EBUSY;
+		return ERR_PTR(-EBUSY);
 
 	new_ctx = ieee80211_alloc_chanctx(local, chanreq, mode, -1);
 	if (!new_ctx)
-				return -ENOMEM;
+		return ERR_PTR(-ENOMEM);
 
 	new_ctx->replace_ctx = curr_ctx;
-			new_ctx->replace_state =
-					IEEE80211_CHANCTX_REPLACES_OTHER;
+	new_ctx->replace_state = IEEE80211_CHANCTX_REPLACES_OTHER;
 
 	curr_ctx->replace_ctx = new_ctx;
-			curr_ctx->replace_state =
-					IEEE80211_CHANCTX_WILL_BE_REPLACED;
+	curr_ctx->replace_state = IEEE80211_CHANCTX_WILL_BE_REPLACED;
 
 	list_add_rcu(&new_ctx->list, &local->chanctx_list);
-		}
+
+	return new_ctx;
+}
+
+int ieee80211_link_reserve_chanctx(struct ieee80211_link_data *link,
+				   const struct ieee80211_chan_req *chanreq,
+				   enum ieee80211_chanctx_mode mode,
+				   bool radar_required)
+{
+	struct ieee80211_sub_if_data *sdata = link->sdata;
+	struct ieee80211_local *local = sdata->local;
+	struct ieee80211_chanctx *new_ctx, *curr_ctx;
+
+	lockdep_assert_wiphy(local->hw.wiphy);
+
+	curr_ctx = ieee80211_link_get_chanctx(link);
+	if (curr_ctx && !local->ops->switch_vif_chanctx)
+		return -EOPNOTSUPP;
+
+	new_ctx = ieee80211_find_reservation_chanctx(local, chanreq, mode);
+	if (!new_ctx) {
+		if (ieee80211_can_create_new_chanctx(local, -1))
+			new_ctx = ieee80211_new_chanctx(local, chanreq, mode,
+							false);
+		else
+			new_ctx = ieee80211_replace_chanctx(local, chanreq,
+							    mode, curr_ctx);
+		if (IS_ERR(new_ctx))
+			return PTR_ERR(new_ctx);
 	}
 
 	list_add(&link->reserved_chanctx_list, &new_ctx->reserved_links);