drm/msm: don't track fbdev's gem object separately

The drm_framebuffer is refcnt'd these days and will unref the underlying
bo as needed.  So we can simplify a little.
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/msm_fbdev.c

@@ -35,7 +35,6 @@ static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma);
 struct msm_fbdev {
 	struct drm_fb_helper base;
 	struct drm_framebuffer *fb;
-	struct drm_gem_object *bo;
 };
 
 static struct fb_ops msm_fb_ops = {
@@ -57,16 +56,16 @@ static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
 {
 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
 	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
-	struct drm_gem_object *drm_obj = fbdev->bo;
+	struct drm_gem_object *bo = msm_framebuffer_bo(fbdev->fb, 0);
 	int ret = 0;
 
-	ret = drm_gem_mmap_obj(drm_obj, drm_obj->size, vma);
+	ret = drm_gem_mmap_obj(bo, bo->size, vma);
 	if (ret) {
 		pr_err("%s:drm_gem_mmap_obj fail\n", __func__);
 		return ret;
 	}
 
-	return msm_gem_mmap_obj(drm_obj, vma);
+	return msm_gem_mmap_obj(bo, vma);
 }
 
 static int msm_fbdev_create(struct drm_fb_helper *helper,
@@ -76,6 +75,7 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
 	struct drm_device *dev = helper->dev;
 	struct msm_drm_private *priv = dev->dev_private;
 	struct drm_framebuffer *fb = NULL;
+	struct drm_gem_object *bo;
 	struct fb_info *fbi = NULL;
 	struct drm_mode_fb_cmd2 mode_cmd = {0};
 	uint64_t paddr;
@@ -97,26 +97,28 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
 	/* allocate backing bo */
 	size = mode_cmd.pitches[0] * mode_cmd.height;
 	DBG("allocating %d bytes for fb %d", size, dev->primary->index);
-	fbdev->bo = msm_gem_new(dev, size, MSM_BO_SCANOUT |
+	bo = msm_gem_new(dev, size, MSM_BO_SCANOUT |
 			MSM_BO_WC | MSM_BO_STOLEN);
-	if (IS_ERR(fbdev->bo)) {
-		ret = PTR_ERR(fbdev->bo);
-		fbdev->bo = NULL;
+	if (IS_ERR(bo)) {
+		ret = PTR_ERR(bo);
+		bo = NULL;
 		dev_err(dev->dev, "failed to allocate buffer object: %d\n", ret);
 		goto fail;
 	}
 
-	fb = msm_framebuffer_init(dev, &mode_cmd, &fbdev->bo);
+	fb = msm_framebuffer_init(dev, &mode_cmd, &bo);
 	if (IS_ERR(fb)) {
 		dev_err(dev->dev, "failed to allocate fb\n");
 		/* note: if fb creation failed, we can't rely on fb destroy
 		 * to unref the bo:
 		 */
-		drm_gem_object_unreference_unlocked(fbdev->bo);
+		drm_gem_object_unreference_unlocked(bo);
 		ret = PTR_ERR(fb);
 		goto fail;
 	}
 
+	bo = msm_framebuffer_bo(fb, 0);
+
 	mutex_lock(&dev->struct_mutex);
 
 	/*
@@ -124,7 +126,7 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
 	 * in panic (ie. lock-safe, etc) we could avoid pinning the
 	 * buffer now:
 	 */
-	ret = msm_gem_get_iova(fbdev->bo, priv->kms->aspace, &paddr);
+	ret = msm_gem_get_iova(bo, priv->kms->aspace, &paddr);
 	if (ret) {
 		dev_err(dev->dev, "failed to get buffer obj iova: %d\n", ret);
 		goto fail_unlock;
@@ -153,14 +155,14 @@ static int msm_fbdev_create(struct drm_fb_helper *helper,
 
 	dev->mode_config.fb_base = paddr;
 
-	fbi->screen_base = msm_gem_get_vaddr(fbdev->bo);
+	fbi->screen_base = msm_gem_get_vaddr(bo);
 	if (IS_ERR(fbi->screen_base)) {
 		ret = PTR_ERR(fbi->screen_base);
 		goto fail_unlock;
 	}
-	fbi->screen_size = fbdev->bo->size;
+	fbi->screen_size = bo->size;
 	fbi->fix.smem_start = paddr;
-	fbi->fix.smem_len = fbdev->bo->size;
+	fbi->fix.smem_len = bo->size;
 
 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
 	DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
@@ -242,7 +244,9 @@ void msm_fbdev_free(struct drm_device *dev)
 
 	/* this will free the backing object */
 	if (fbdev->fb) {
-		msm_gem_put_vaddr(fbdev->bo);
+		struct drm_gem_object *bo =
+			msm_framebuffer_bo(fbdev->fb, 0);
+		msm_gem_put_vaddr(bo);
 		drm_framebuffer_remove(fbdev->fb);
 	}