1 files changed, 42 insertions, 19 deletions

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 7bb3845d9974..aeee083c7f95 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -1432,6 +1432,45 @@ static int atomic_set_prop(struct drm_atomic_state *state,
         return ret;
 }
 
+/**
+ * drm_atomic_update_old_fb -- Unset old_fb pointers and set plane->fb pointers.
+ *
+ * @dev: drm device to check.
+ * @plane_mask: plane mask for planes that were updated.
+ * @ret: return value, can be -EDEADLK for a retry.
+ *
+ * Before doing an update plane->old_fb is set to plane->fb,
+ * but before dropping the locks old_fb needs to be set to NULL
+ * and plane->fb updated. This is a common operation for each
+ * atomic update, so this call is split off as a helper.
+ */
+void drm_atomic_clean_old_fb(struct drm_device *dev,
+                             unsigned plane_mask,
+                             int ret)
+{
+        struct drm_plane *plane;
+
+        /* if succeeded, fixup legacy plane crtc/fb ptrs before dropping
+         * locks (ie. while it is still safe to deref plane->state).  We
+         * need to do this here because the driver entry points cannot
+         * distinguish between legacy and atomic ioctls.
+         */
+        drm_for_each_plane_mask(plane, dev, plane_mask) {
+                if (ret == 0) {
+                        struct drm_framebuffer *new_fb = plane->state->fb;
+                        if (new_fb)
+                                drm_framebuffer_reference(new_fb);
+                        plane->fb = new_fb;
+                        plane->crtc = plane->state->crtc;
+
+                        if (plane->old_fb)
+                                drm_framebuffer_unreference(plane->old_fb);
+                }
+                plane->old_fb = NULL;
+        }
+}
+EXPORT_SYMBOL(drm_atomic_clean_old_fb);
+
 int drm_mode_atomic_ioctl(struct drm_device *dev,
                           void *data, struct drm_file *file_priv)
 {
@@ -1446,7 +1485,7 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
         struct drm_plane *plane;
         struct drm_crtc *crtc;
         struct drm_crtc_state *crtc_state;
-        unsigned plane_mask = 0;
+        unsigned plane_mask;
         int ret = 0;
         unsigned int i, j;
 
@@ -1486,6 +1525,7 @@ int drm_mode_atomic_ioctl(struct drm_device *dev,
         state->allow_modeset = !!(arg->flags & DRM_MODE_ATOMIC_ALLOW_MODESET);
 
 retry:
+        plane_mask = 0;
         copied_objs = 0;
         copied_props = 0;
 
@@ -1576,24 +1616,7 @@ retry:
         }
 
 out:
-        /* if succeeded, fixup legacy plane crtc/fb ptrs before dropping
-         * locks (ie. while it is still safe to deref plane->state).  We
-         * need to do this here because the driver entry points cannot
-         * distinguish between legacy and atomic ioctls.
-         */
-        drm_for_each_plane_mask(plane, dev, plane_mask) {
-                if (ret == 0) {
-                        struct drm_framebuffer *new_fb = plane->state->fb;
-                        if (new_fb)
-                                drm_framebuffer_reference(new_fb);
-                        plane->fb = new_fb;
-                        plane->crtc = plane->state->crtc;
-
-                        if (plane->old_fb)
-                                drm_framebuffer_unreference(plane->old_fb);
-                }
-                plane->old_fb = NULL;
-        }
+        drm_atomic_clean_old_fb(dev, plane_mask, ret);
 
         if (ret && arg->flags & DRM_MODE_PAGE_FLIP_EVENT) {
                 /*