1 files changed, 67 insertions, 19 deletions

diff --git a/drivers/gpu/drm/qxl/qxl_display.c b/drivers/gpu/drm/qxl/qxl_display.c
index 14c5613b4388..4756b3c9bf2c 100644
--- a/drivers/gpu/drm/qxl/qxl_display.c
+++ b/drivers/gpu/drm/qxl/qxl_display.c
@@ -305,7 +305,9 @@ static const struct drm_crtc_funcs qxl_crtc_funcs = {
 void qxl_user_framebuffer_destroy(struct drm_framebuffer *fb)
 {
 	struct qxl_framebuffer *qxl_fb = to_qxl_framebuffer(fb);
+	struct qxl_bo *bo = gem_to_qxl_bo(qxl_fb->obj);
 
+	WARN_ON(bo->shadow);
 	drm_gem_object_unreference_unlocked(qxl_fb->obj);
 	drm_framebuffer_cleanup(fb);
 	kfree(qxl_fb);
@@ -508,24 +510,35 @@ static void qxl_primary_atomic_update(struct drm_plane *plane,
 	    .x2 = qfb->base.width,
 	    .y2 = qfb->base.height
 	};
+	bool same_shadow = false;
 
-	if (!old_state->fb) {
-		qxl_io_log(qdev,
-			   "create primary fb: %dx%d,%d,%d\n",
-			   bo->surf.width, bo->surf.height,
-			   bo->surf.stride, bo->surf.format);
+	if (old_state->fb) {
+		qfb_old = to_qxl_framebuffer(old_state->fb);
+		bo_old = gem_to_qxl_bo(qfb_old->obj);
+	} else {
+		bo_old = NULL;
+	}
 
-		qxl_io_create_primary(qdev, 0, bo);
-		bo->is_primary = true;
+	if (bo == bo_old)
 		return;
 
-	} else {
-		qfb_old = to_qxl_framebuffer(old_state->fb);
-		bo_old = gem_to_qxl_bo(qfb_old->obj);
+	if (bo_old && bo_old->shadow && bo->shadow &&
+	    bo_old->shadow == bo->shadow) {
+		same_shadow = true;
+	}
+
+	if (bo_old && bo_old->is_primary) {
+		if (!same_shadow)
+			qxl_io_destroy_primary(qdev);
 		bo_old->is_primary = false;
 	}
 
-	bo->is_primary = true;
+	if (!bo->is_primary) {
+		if (!same_shadow)
+			qxl_io_create_primary(qdev, 0, bo);
+		bo->is_primary = true;
+	}
+
 	qxl_draw_dirty_fb(qdev, qfb, bo, 0, 0, &norect, 1, 1);
 }
 
@@ -534,13 +547,15 @@ static void qxl_primary_atomic_disable(struct drm_plane *plane,
 {
 	struct qxl_device *qdev = plane->dev->dev_private;
 
-	if (old_state->fb)
-	{	struct qxl_framebuffer *qfb =
+	if (old_state->fb) {
+		struct qxl_framebuffer *qfb =
 			to_qxl_framebuffer(old_state->fb);
 		struct qxl_bo *bo = gem_to_qxl_bo(qfb->obj);
 
-		qxl_io_destroy_primary(qdev);
-		bo->is_primary = false;
+		if (bo->is_primary) {
+			qxl_io_destroy_primary(qdev);
+			bo->is_primary = false;
+		}
 	}
 }
 
@@ -675,8 +690,9 @@ static void qxl_cursor_atomic_disable(struct drm_plane *plane,
 static int qxl_plane_prepare_fb(struct drm_plane *plane,
 				struct drm_plane_state *new_state)
 {
+	struct qxl_device *qdev = plane->dev->dev_private;
 	struct drm_gem_object *obj;
-	struct qxl_bo *user_bo;
+	struct qxl_bo *user_bo, *old_bo = NULL;
 	int ret;
 
 	if (!new_state->fb)
@@ -685,6 +701,32 @@ static int qxl_plane_prepare_fb(struct drm_plane *plane,
 	obj = to_qxl_framebuffer(new_state->fb)->obj;
 	user_bo = gem_to_qxl_bo(obj);
 
+	if (plane->type == DRM_PLANE_TYPE_PRIMARY &&
+	    user_bo->is_dumb && !user_bo->shadow) {
+		if (plane->state->fb) {
+			obj = to_qxl_framebuffer(plane->state->fb)->obj;
+			old_bo = gem_to_qxl_bo(obj);
+		}
+		if (old_bo && old_bo->shadow &&
+		    user_bo->gem_base.size == old_bo->gem_base.size &&
+		    plane->state->crtc     == new_state->crtc &&
+		    plane->state->crtc_w   == new_state->crtc_w &&
+		    plane->state->crtc_h   == new_state->crtc_h &&
+		    plane->state->src_x    == new_state->src_x &&
+		    plane->state->src_y    == new_state->src_y &&
+		    plane->state->src_w    == new_state->src_w &&
+		    plane->state->src_h    == new_state->src_h &&
+		    plane->state->rotation == new_state->rotation &&
+		    plane->state->zpos     == new_state->zpos) {
+			drm_gem_object_get(&old_bo->shadow->gem_base);
+			user_bo->shadow = old_bo->shadow;
+		} else {
+			qxl_bo_create(qdev, user_bo->gem_base.size,
+				      true, true, QXL_GEM_DOMAIN_VRAM, NULL,
+				      &user_bo->shadow);
+		}
+	}
+
 	ret = qxl_bo_pin(user_bo, QXL_GEM_DOMAIN_CPU, NULL);
 	if (ret)
 		return ret;
@@ -698,16 +740,22 @@ static void qxl_plane_cleanup_fb(struct drm_plane *plane,
 	struct drm_gem_object *obj;
 	struct qxl_bo *user_bo;
 
-	if (!plane->state->fb) {
-		/* we never executed prepare_fb, so there's nothing to
+	if (!old_state->fb) {
+		/*
+		 * we never executed prepare_fb, so there's nothing to
 		 * unpin.
 		 */
 		return;
 	}
 
-	obj = to_qxl_framebuffer(plane->state->fb)->obj;
+	obj = to_qxl_framebuffer(old_state->fb)->obj;
 	user_bo = gem_to_qxl_bo(obj);
 	qxl_bo_unpin(user_bo);
+
+	if (user_bo->shadow && !user_bo->is_primary) {
+		drm_gem_object_put_unlocked(&user_bo->shadow->gem_base);
+		user_bo->shadow = NULL;
+	}
 }
 
 static const uint32_t qxl_cursor_plane_formats[] = {