wifi: cfg80211: define and use wiphy guard

Define a guard for the wiphy mutex, and use it in
most code in cfg80211, though not all due to some
interaction with RTNL and/or indentation.

Suggested-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Reviewed-by: Jeff Johnson <quic_jjohnson@quicinc.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Link: https://patch.msgid.link/20241122094225.88765cbaab65.I610c9b14f36902e75e1d13f0db29f8bef2298804@changeid
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 25 insertions, 30 deletions

diff --git a/net/wireless/reg.c b/net/wireless/reg.c
index 1df65a5a44f7..2dd0533e7660 100644
--- a/net/wireless/reg.c
+++ b/net/wireless/reg.c
@@ -2465,11 +2465,11 @@ static void reg_leave_invalid_chans(struct wiphy *wiphy)
 	struct wireless_dev *wdev;
 	struct cfg80211_registered_device *rdev = wiphy_to_rdev(wiphy);
 
-	wiphy_lock(wiphy);
+	guard(wiphy)(wiphy);
+
 	list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list)
 		if (!reg_wdev_chan_valid(wiphy, wdev))
 			cfg80211_leave(rdev, wdev);
-	wiphy_unlock(wiphy);
 }
 
 static void reg_check_chans_work(struct work_struct *work)
@@ -2649,13 +2649,11 @@ void wiphy_apply_custom_regulatory(struct wiphy *wiphy,
 		return;
 
 	rtnl_lock();
-	wiphy_lock(wiphy);
-
-	tmp = get_wiphy_regdom(wiphy);
-	rcu_assign_pointer(wiphy->regd, new_regd);
-	rcu_free_regdom(tmp);
-
-	wiphy_unlock(wiphy);
+	scoped_guard(wiphy, wiphy) {
+		tmp = get_wiphy_regdom(wiphy);
+		rcu_assign_pointer(wiphy->regd, new_regd);
+		rcu_free_regdom(tmp);
+	}
 	rtnl_unlock();
 }
 EXPORT_SYMBOL(wiphy_apply_custom_regulatory);
@@ -2825,9 +2823,9 @@ reg_process_hint_driver(struct wiphy *wiphy,
 
 		tmp = get_wiphy_regdom(wiphy);
 		ASSERT_RTNL();
-		wiphy_lock(wiphy);
-		rcu_assign_pointer(wiphy->regd, regd);
-		wiphy_unlock(wiphy);
+		scoped_guard(wiphy, wiphy) {
+			rcu_assign_pointer(wiphy->regd, regd);
+		}
 		rcu_free_regdom(tmp);
 	}
 
@@ -3205,9 +3203,9 @@ static void reg_process_self_managed_hints(void)
 	ASSERT_RTNL();
 
 	for_each_rdev(rdev) {
-		wiphy_lock(&rdev->wiphy);
+		guard(wiphy)(&rdev->wiphy);
+
 		reg_process_self_managed_hint(&rdev->wiphy);
-		wiphy_unlock(&rdev->wiphy);
 	}
 
 	reg_check_channels();
@@ -3600,14 +3598,12 @@ static bool is_wiphy_all_set_reg_flag(enum ieee80211_regulatory_flags flag)
 	struct wireless_dev *wdev;
 
 	for_each_rdev(rdev) {
-		wiphy_lock(&rdev->wiphy);
+		guard(wiphy)(&rdev->wiphy);
+
 		list_for_each_entry(wdev, &rdev->wiphy.wdev_list, list) {
-			if (!(wdev->wiphy->regulatory_flags & flag)) {
-				wiphy_unlock(&rdev->wiphy);
+			if (!(wdev->wiphy->regulatory_flags & flag))
 				return false;
-			}
 		}
-		wiphy_unlock(&rdev->wiphy);
 	}
 
 	return true;
@@ -3883,19 +3879,18 @@ static int reg_set_rd_driver(const struct ieee80211_regdomain *rd,
 
 	if (!driver_request->intersect) {
 		ASSERT_RTNL();
-		wiphy_lock(request_wiphy);
-		if (request_wiphy->regd)
-			tmp = get_wiphy_regdom(request_wiphy);
-
-		regd = reg_copy_regd(rd);
-		if (IS_ERR(regd)) {
-			wiphy_unlock(request_wiphy);
-			return PTR_ERR(regd);
+		scoped_guard(wiphy, request_wiphy) {
+			if (request_wiphy->regd)
+				tmp = get_wiphy_regdom(request_wiphy);
+
+			regd = reg_copy_regd(rd);
+			if (IS_ERR(regd))
+				return PTR_ERR(regd);
+
+			rcu_assign_pointer(request_wiphy->regd, regd);
+			rcu_free_regdom(tmp);
 		}
 
-		rcu_assign_pointer(request_wiphy->regd, regd);
-		rcu_free_regdom(tmp);
-		wiphy_unlock(request_wiphy);
 		reset_regdomains(false, rd);
 		return 0;
 	}