drm: Put legacy lastclose work into drm_legacy_dev_reinit

Except for the ->lasclose driver callback evrything in drm_lastclose()
is all legacy cruft and can be hidden. Which means another
dev->struct_mutex site disappears entirely for modern drivers!

Also while at it change the return value of drm_lastclose to void
since it will always succeed. No one checks the return value of
close() anyway, ever.

v2: Move misplaced hunk, spotted by 0day.

Cc: Thierry Reding <thierry.reding@gmail.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1461691808-12414-3-git-send-email-daniel.vetter@ffwll.ch

drivers/gpu/drm/drm_fops.c

@@ -381,14 +381,26 @@ static void drm_events_release(struct drm_file *file_priv)
  */
 static void drm_legacy_dev_reinit(struct drm_device *dev)
 {
-	if (drm_core_check_feature(dev, DRIVER_MODESET))
-		return;
+	if (dev->irq_enabled)
+		drm_irq_uninstall(dev);
+
+	mutex_lock(&dev->struct_mutex);
+
+	drm_legacy_agp_clear(dev);
+
+	drm_legacy_sg_cleanup(dev);
+	drm_legacy_vma_flush(dev);
+	drm_legacy_dma_takedown(dev);
+
+	mutex_unlock(&dev->struct_mutex);
 
 	dev->sigdata.lock = NULL;
 
 	dev->context_flag = 0;
 	dev->last_context = 0;
 	dev->if_version = 0;
+
+	DRM_DEBUG("lastclose completed\n");
 }
 
 /*
@@ -400,31 +412,16 @@ static void drm_legacy_dev_reinit(struct drm_device *dev)
  *
  * \sa drm_device
  */
-int drm_lastclose(struct drm_device * dev)
+void drm_lastclose(struct drm_device * dev)
 {
 	DRM_DEBUG("\n");
 
 	if (dev->driver->lastclose)
 		dev->driver->lastclose(dev);
 	DRM_DEBUG("driver lastclose completed\n");
 
-	if (dev->irq_enabled && !drm_core_check_feature(dev, DRIVER_MODESET))
-		drm_irq_uninstall(dev);
-
-	mutex_lock(&dev->struct_mutex);
-
-	drm_legacy_agp_clear(dev);
-
-	drm_legacy_sg_cleanup(dev);
-	drm_legacy_vma_flush(dev);
-	drm_legacy_dma_takedown(dev);
-
-	mutex_unlock(&dev->struct_mutex);
-
-	drm_legacy_dev_reinit(dev);
-
-	DRM_DEBUG("lastclose completed\n");
-	return 0;
+	if (!drm_core_check_feature(dev, DRIVER_MODESET))
+		drm_legacy_dev_reinit(dev);
 }
 
 /**
@@ -445,7 +442,6 @@ int drm_release(struct inode *inode, struct file *filp)
 	struct drm_file *file_priv = filp->private_data;
 	struct drm_minor *minor = file_priv->minor;
 	struct drm_device *dev = minor->dev;
-	int retcode = 0;
 
 	mutex_lock(&drm_global_mutex);
 
@@ -538,15 +534,15 @@ int drm_release(struct inode *inode, struct file *filp)
 	 */
 
 	if (!--dev->open_count) {
-		retcode = drm_lastclose(dev);
+		drm_lastclose(dev);
 		if (drm_device_is_unplugged(dev))
 			drm_put_dev(dev);
 	}
 	mutex_unlock(&drm_global_mutex);
 
 	drm_minor_release(minor);
 
-	return retcode;
+	return 0;
 }
 EXPORT_SYMBOL(drm_release);
 

drivers/gpu/drm/drm_internal.h

@@ -26,7 +26,7 @@ extern unsigned int drm_timestamp_monotonic;
 
 /* drm_fops.c */
 extern struct mutex drm_global_mutex;
-int drm_lastclose(struct drm_device *dev);
+void drm_lastclose(struct drm_device *dev);
 
 /* drm_pci.c */
 int drm_pci_set_unique(struct drm_device *dev,