[RFC PATCH v2 1/4] virtio: separate PM restore and reset_done paths

[Sungho Bae]

From: Sungho Bae <baver.bae@xxxxxxx>

Refactor virtio_device_restore_priv() by extracting the common device
re-initialization sequence into virtio_device_reinit(). This helper
performs the full bring-up sequence: reset, status acknowledgment,
feature finalization, and feature negotiation.

virtio_device_restore() and virtio_device_reset_done() now each call
virtio_device_reinit() directly instead of going through a boolean-
dispatched wrapper. This makes each path independently readable and
extensible without further complicating the dispatch logic.

A follow-up series will add noirq PM callbacks that only affect the
restore path; having the two paths separated avoids adding more
conditionals to a shared function.

No functional change.

Signed-off-by: Sungho Bae <baver.bae@xxxxxxx>
---
 drivers/virtio/virtio.c | 78 +++++++++++++++++++++++++----------------
 1 file changed, 47 insertions(+), 31 deletions(-)

diff --git a/drivers/virtio/virtio.c b/drivers/virtio/virtio.c
index 5bdc6b82b30b..b0668434ac21 100644
--- a/drivers/virtio/virtio.c
+++ b/drivers/virtio/virtio.c
@@ -588,7 +588,7 @@ void unregister_virtio_device(struct virtio_device *dev)
 }
 EXPORT_SYMBOL_GPL(unregister_virtio_device);
 
-static int virtio_device_restore_priv(struct virtio_device *dev, bool restore)
+static int virtio_device_reinit(struct virtio_device *dev)
 {
 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
 	int ret;
@@ -613,35 +613,9 @@ static int virtio_device_restore_priv(struct virtio_device *dev, bool restore)
 
 	ret = dev->config->finalize_features(dev);
 	if (ret)
-		goto err;
-
-	ret = virtio_features_ok(dev);
-	if (ret)
-		goto err;
-
-	if (restore) {
-		if (drv->restore) {
-			ret = drv->restore(dev);
-			if (ret)
-				goto err;
-		}
-	} else {
-		ret = drv->reset_done(dev);
-		if (ret)
-			goto err;
-	}
-
-	/* If restore didn't do it, mark device DRIVER_OK ourselves. */
-	if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK))
-		virtio_device_ready(dev);
-
-	virtio_config_core_enable(dev);
-
-	return 0;
+		return ret;
 
-err:
-	virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
-	return ret;
+	return virtio_features_ok(dev);
 }
 
 #ifdef CONFIG_PM_SLEEP
@@ -668,7 +642,30 @@ EXPORT_SYMBOL_GPL(virtio_device_freeze);
 
 int virtio_device_restore(struct virtio_device *dev)
 {
-	return virtio_device_restore_priv(dev, true);
+	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+	int ret;
+
+	ret = virtio_device_reinit(dev);
+	if (ret)
+		goto err;
+
+	if (drv && drv->restore) {
+		ret = drv->restore(dev);
+		if (ret)
+			goto err;
+	}
+
+	/* If restore didn't do it, mark device DRIVER_OK ourselves. */
+	if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK))
+		virtio_device_ready(dev);
+
+	virtio_config_core_enable(dev);
+
+	return 0;
+
+err:
+	virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(virtio_device_restore);
 #endif
@@ -698,11 +695,30 @@ EXPORT_SYMBOL_GPL(virtio_device_reset_prepare);
 int virtio_device_reset_done(struct virtio_device *dev)
 {
 	struct virtio_driver *drv = drv_to_virtio(dev->dev.driver);
+	int ret;
 
 	if (!drv || !drv->reset_done)
 		return -EOPNOTSUPP;
 
-	return virtio_device_restore_priv(dev, false);
+	ret = virtio_device_reinit(dev);
+	if (ret)
+		goto err;
+
+	ret = drv->reset_done(dev);
+	if (ret)
+		goto err;
+
+	/* If reset_done didn't do it, mark device DRIVER_OK ourselves. */
+	if (!(dev->config->get_status(dev) & VIRTIO_CONFIG_S_DRIVER_OK))
+		virtio_device_ready(dev);
+
+	virtio_config_core_enable(dev);
+
+	return 0;
+
+err:
+	virtio_add_status(dev, VIRTIO_CONFIG_S_FAILED);
+	return ret;
 }
 EXPORT_SYMBOL_GPL(virtio_device_reset_done);
 
-- 
2.43.0