[RFC PATCH 31/37] drm: crtc_helper: Reference, not duplicate, modes

[Daniel Stone]

Take a reference to existing modes, rather than duplicating them to
create new ones.

Signed-off-by: Daniel Stone <daniels at collabora.com>
---
 drivers/gpu/drm/drm_crtc_helper.c | 43 ++++++++++++++++-----------------------
 1 file changed, 17 insertions(+), 26 deletions(-)

diff --git a/drivers/gpu/drm/drm_crtc_helper.c b/drivers/gpu/drm/drm_crtc_helper.c
index c23f31f..08f0367 100644
--- a/drivers/gpu/drm/drm_crtc_helper.c
+++ b/drivers/gpu/drm/drm_crtc_helper.c
@@ -301,7 +301,7 @@ bool drm_crtc_helper_set_mode(struct drm_crtc *crtc,
 	 * setting.
 	 */
 	if (mode)
-		crtc->mode = drm_mode_duplicate(crtc->dev, mode);
+		crtc->mode = drm_mode_reference(mode);
 	else
 		crtc->mode = NULL;
 	crtc->x = x;
@@ -421,7 +421,8 @@ done:
 		crtc->x = saved_x;
 		crtc->y = saved_y;
 	} else {
-		drm_mode_destroy(dev, saved_mode);
+		if (saved_mode)
+			drm_mode_destroy(dev, saved_mode);
 	}
 
 	return ret;
@@ -547,7 +548,10 @@ int drm_crtc_helper_set_config(struct drm_mode_set *set)
 	}
 
 	save_set.crtc = set->crtc;
-	save_set.mode = set->crtc->mode;
+	if (set->crtc->mode)
+		save_set.mode = drm_mode_reference(set->crtc->mode);
+	else
+		save_set.mode = NULL;
 	save_set.x = set->crtc->x;
 	save_set.y = set->crtc->y;
 	save_set.fb = set->crtc->primary->fb;
@@ -718,6 +722,8 @@ fail:
 				      save_set.y, save_set.fb))
 		DRM_ERROR("failed to restore config after modeset failure\n");
 
+	if (save_set.mode)
+		drm_mode_destroy(dev, save_set.mode);
 	kfree(save_connectors);
 	kfree(save_encoders);
 	return ret;
@@ -954,29 +960,9 @@ int drm_helper_crtc_mode_set(struct drm_crtc *crtc,
 	else if (crtc->state) {
 		crtc_state = kmemdup(crtc->state, sizeof(*crtc_state),
 				     GFP_KERNEL);
-		/* XXX: this is unpleasant: we should mandate dup instead */
-		if (crtc_state) {
-			crtc_state->mode =
-				drm_mode_duplicate(crtc->dev,
-				                   crtc->state->mode);
-			if (!crtc_state->mode) {
-				kfree(crtc_state);
-				crtc_state = NULL;
-			}
-		}
 	}
-	else {
+	else
 		crtc_state = kzalloc(sizeof(*crtc_state), GFP_KERNEL);
-		if (crtc_state) {
-			crtc_state->mode = kzalloc(sizeof(*crtc_state->mode),
-			                           GFP_KERNEL);
-			/* XXX: as above, but mandate a new_state */
-			if (!crtc_state->mode) {
-				kfree(crtc_state);
-				crtc_state = NULL;
-			}
-		}
-	}
 	if (!crtc_state)
 		return -ENOMEM;
 	crtc_state->crtc = crtc;
@@ -984,7 +970,12 @@ int drm_helper_crtc_mode_set(struct drm_crtc *crtc,
 	crtc_state->enable = true;
 	crtc_state->planes_changed = true;
 	crtc_state->mode_changed = true;
-	drm_mode_copy(crtc_state->mode, mode);
+	if (crtc_state->mode)
+		drm_mode_destroy(crtc->dev, crtc_state->mode);
+	if (mode)
+		crtc_state->mode = drm_mode_reference(mode);
+	else
+		crtc_state->mode = NULL;
 	drm_mode_copy(&crtc_state->adjusted_mode, adjusted_mode);
 
 	if (crtc_funcs->atomic_check) {
@@ -1006,7 +997,7 @@ int drm_helper_crtc_mode_set(struct drm_crtc *crtc,
 		if (crtc->funcs->atomic_destroy_state)
 			crtc->funcs->atomic_destroy_state(crtc, crtc_state);
 		else {
-			kfree(crtc_state->mode);
+			drm_mode_destroy(crtc->dev, crtc_state->mode);
 			kfree(crtc_state);
 		}
 	}
-- 
2.3.2