drm/virtio: Wait for each dma-fence of in-fence array individually

Use dma-fence-unwrap API for waiting each dma-fence of the in-fence array
individually. Sync file's in-fence array always has a non-matching fence
context ID, which doesn't allow to skip waiting of fences with a matching
context ID in a case of a merged sync file fence.
Suggested-by: Rob Clark <robdclark@gmail.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>
Tested-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com>
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230416115237.798604-3-dmitry.osipenko@collabora.com

drivers/gpu/drm/virtio/virtgpu_submit.c

@@ -32,7 +32,7 @@ struct virtio_gpu_submit {
 	void *buf;
 };
 
-static int virtio_gpu_dma_fence_wait(struct virtio_gpu_submit *submit,
+static int virtio_gpu_do_fence_wait(struct virtio_gpu_submit *submit,
 				    struct dma_fence *in_fence)
 {
 	u32 context = submit->fence_ctx + submit->ring_idx;
@@ -43,6 +43,22 @@ static int virtio_gpu_dma_fence_wait(struct virtio_gpu_submit *submit,
 	return dma_fence_wait(in_fence, true);
 }
 
+static int virtio_gpu_dma_fence_wait(struct virtio_gpu_submit *submit,
+				     struct dma_fence *fence)
+{
+	struct dma_fence_unwrap itr;
+	struct dma_fence *f;
+	int err;
+
+	dma_fence_unwrap_for_each(f, &itr, fence) {
+		err = virtio_gpu_do_fence_wait(submit, f);
+		if (err)
+			return err;
+	}
+
+	return 0;
+}
+
 static int virtio_gpu_fence_event_create(struct drm_device *dev,
 					 struct drm_file *file,
 					 struct virtio_gpu_fence *fence,