3 files changed, 46 insertions, 66 deletions

diff --git a/include/net/switchdev.h b/include/net/switchdev.h
index d1c7f901ea61..f7de6f8e9a4c 100644
--- a/include/net/switchdev.h
+++ b/include/net/switchdev.h
@@ -17,6 +17,7 @@
 
 #define SWITCHDEV_F_NO_RECURSE		BIT(0)
 #define SWITCHDEV_F_SKIP_EOPNOTSUPP	BIT(1)
+#define SWITCHDEV_F_DEFER		BIT(2)
 
 struct switchdev_trans_item {
 	struct list_head list;
diff --git a/net/bridge/br_stp.c b/net/bridge/br_stp.c
index db6d243defb2..80c34d70218c 100644
--- a/net/bridge/br_stp.c
+++ b/net/bridge/br_stp.c
@@ -41,13 +41,14 @@ void br_set_state(struct net_bridge_port *p, unsigned int state)
 {
 	struct switchdev_attr attr = {
 		.id = SWITCHDEV_ATTR_ID_PORT_STP_STATE,
+		.flags = SWITCHDEV_F_DEFER,
 		.u.stp_state = state,
 	};
 	int err;
 
 	p->state = state;
 	err = switchdev_port_attr_set(p->dev, &attr);
-	if (err && err != -EOPNOTSUPP)
+	if (err)
 		br_warn(p->br, "error setting offload STP state on port %u(%s)\n",
 				(unsigned int) p->port_no, p->dev->name);
 }
diff --git a/net/switchdev/switchdev.c b/net/switchdev/switchdev.c
index 23b4e5b347dc..007b8f40df06 100644
--- a/net/switchdev/switchdev.c
+++ b/net/switchdev/switchdev.c
@@ -250,75 +250,12 @@ done:
 	return err;
 }
 
-struct switchdev_attr_set_work {
-	struct work_struct work;
-	struct net_device *dev;
-	struct switchdev_attr attr;
-};
-
-static void switchdev_port_attr_set_work(struct work_struct *work)
-{
-	struct switchdev_attr_set_work *asw =
-		container_of(work, struct switchdev_attr_set_work, work);
-	int err;
-
-	rtnl_lock();
-	err = switchdev_port_attr_set(asw->dev, &asw->attr);
-	if (err && err != -EOPNOTSUPP)
-		netdev_err(asw->dev, "failed (err=%d) to set attribute (id=%d)\n",
-			   err, asw->attr.id);
-	rtnl_unlock();
-
-	dev_put(asw->dev);
-	kfree(work);
-}
-
-static int switchdev_port_attr_set_defer(struct net_device *dev,
-					 const struct switchdev_attr *attr)
-{
-	struct switchdev_attr_set_work *asw;
-
-	asw = kmalloc(sizeof(*asw), GFP_ATOMIC);
-	if (!asw)
-		return -ENOMEM;
-
-	INIT_WORK(&asw->work, switchdev_port_attr_set_work);
-
-	dev_hold(dev);
-	asw->dev = dev;
-	memcpy(&asw->attr, attr, sizeof(asw->attr));
-
-	schedule_work(&asw->work);
-
-	return 0;
-}
-
-/**
- *	switchdev_port_attr_set - Set port attribute
- *
- *	@dev: port device
- *	@attr: attribute to set
- *
- *	Use a 2-phase prepare-commit transaction model to ensure
- *	system is not left in a partially updated state due to
- *	failure from driver/device.
- */
-int switchdev_port_attr_set(struct net_device *dev,
-			    const struct switchdev_attr *attr)
+static int switchdev_port_attr_set_now(struct net_device *dev,
+				       const struct switchdev_attr *attr)
 {
 	struct switchdev_trans trans;
 	int err;
 
-	if (!rtnl_is_locked()) {
-		/* Running prepare-commit transaction across stacked
-		 * devices requires nothing moves, so if rtnl_lock is
-		 * not held, schedule a worker thread to hold rtnl_lock
-		 * while setting attr.
-		 */
-
-		return switchdev_port_attr_set_defer(dev, attr);
-	}
-
 	switchdev_trans_init(&trans);
 
 	/* Phase I: prepare for attr set. Driver/device should fail
@@ -355,6 +292,47 @@ int switchdev_port_attr_set(struct net_device *dev,
 
 	return err;
 }
+
+static void switchdev_port_attr_set_deferred(struct net_device *dev,
+					     const void *data)
+{
+	const struct switchdev_attr *attr = data;
+	int err;
+
+	err = switchdev_port_attr_set_now(dev, attr);
+	if (err && err != -EOPNOTSUPP)
+		netdev_err(dev, "failed (err=%d) to set attribute (id=%d)\n",
+			   err, attr->id);
+}
+
+static int switchdev_port_attr_set_defer(struct net_device *dev,
+					 const struct switchdev_attr *attr)
+{
+	return switchdev_deferred_enqueue(dev, attr, sizeof(*attr),
+					  switchdev_port_attr_set_deferred);
+}
+
+/**
+ *	switchdev_port_attr_set - Set port attribute
+ *
+ *	@dev: port device
+ *	@attr: attribute to set
+ *
+ *	Use a 2-phase prepare-commit transaction model to ensure
+ *	system is not left in a partially updated state due to
+ *	failure from driver/device.
+ *
+ *	rtnl_lock must be held and must not be in atomic section,
+ *	in case SWITCHDEV_F_DEFER flag is not set.
+ */
+int switchdev_port_attr_set(struct net_device *dev,
+			    const struct switchdev_attr *attr)
+{
+	if (attr->flags & SWITCHDEV_F_DEFER)
+		return switchdev_port_attr_set_defer(dev, attr);
+	ASSERT_RTNL();
+	return switchdev_port_attr_set_now(dev, attr);
+}
 EXPORT_SYMBOL_GPL(switchdev_port_attr_set);
 
 static int __switchdev_port_obj_add(struct net_device *dev,