1 files changed, 58 insertions, 3 deletions

diff --git a/drivers/gpu/drm/i915/display/intel_fb.c b/drivers/gpu/drm/i915/display/intel_fb.c
index 446bbf7986b6..e7678571b0d7 100644
--- a/drivers/gpu/drm/i915/display/intel_fb.c
+++ b/drivers/gpu/drm/i915/display/intel_fb.c
@@ -7,11 +7,15 @@
 #include <drm/drm_framebuffer.h>
 #include <drm/drm_modeset_helper.h>
 
+#include <linux/dma-fence.h>
+#include <linux/dma-resv.h>
+
 #include "i915_drv.h"
 #include "intel_display.h"
 #include "intel_display_types.h"
 #include "intel_dpt.h"
 #include "intel_fb.h"
+#include "intel_frontbuffer.h"
 
 #define check_array_bounds(i915, a, i) drm_WARN_ON(&(i915)->drm, (i) >= ARRAY_SIZE(a))
 
@@ -1896,6 +1900,21 @@ static int intel_user_framebuffer_create_handle(struct drm_framebuffer *fb,
 	return drm_gem_handle_create(file, &obj->base, handle);
 }
 
+struct frontbuffer_fence_cb {
+	struct dma_fence_cb base;
+	struct intel_frontbuffer *front;
+};
+
+static void intel_user_framebuffer_fence_wake(struct dma_fence *dma,
+					      struct dma_fence_cb *data)
+{
+	struct frontbuffer_fence_cb *cb = container_of(data, typeof(*cb), base);
+
+	intel_frontbuffer_queue_flush(cb->front);
+	kfree(cb);
+	dma_fence_put(dma);
+}
+
 static int intel_user_framebuffer_dirty(struct drm_framebuffer *fb,
 					struct drm_file *file,
 					unsigned int flags, unsigned int color,
@@ -1903,11 +1922,47 @@ static int intel_user_framebuffer_dirty(struct drm_framebuffer *fb,
 					unsigned int num_clips)
 {
 	struct drm_i915_gem_object *obj = intel_fb_obj(fb);
+	struct intel_frontbuffer *front = to_intel_frontbuffer(fb);
+	struct dma_fence *fence;
+	struct frontbuffer_fence_cb *cb;
+	int ret = 0;
 
-	i915_gem_object_flush_if_display(obj);
-	intel_frontbuffer_flush(to_intel_frontbuffer(fb), ORIGIN_DIRTYFB);
+	if (!atomic_read(&front->bits))
+		return 0;
 
-	return 0;
+	if (dma_resv_test_signaled(obj->base.resv, dma_resv_usage_rw(false)))
+		goto flush;
+
+	ret = dma_resv_get_singleton(obj->base.resv, dma_resv_usage_rw(false),
+				     &fence);
+	if (ret || !fence)
+		goto flush;
+
+	cb = kmalloc(sizeof(*cb), GFP_KERNEL);
+	if (!cb) {
+		dma_fence_put(fence);
+		ret = -ENOMEM;
+		goto flush;
+	}
+
+	cb->front = front;
+
+	intel_frontbuffer_invalidate(front, ORIGIN_DIRTYFB);
+
+	ret = dma_fence_add_callback(fence, &cb->base,
+				     intel_user_framebuffer_fence_wake);
+	if (ret) {
+		intel_user_framebuffer_fence_wake(fence, &cb->base);
+		if (ret == -ENOENT)
+			ret = 0;
+	}
+
+	return ret;
+
+flush:
+	i915_gem_object_flush_if_display(obj);
+	intel_frontbuffer_flush(front, ORIGIN_DIRTYFB);
+	return ret;
 }
 
 static const struct drm_framebuffer_funcs intel_fb_funcs = {