drm/i915: cleanup: drm_modeset_lock_all() --> DRM_MODESET_LOCK_ALL_BEGIN() part 2

As requested in Documentation/gpu/todo.rst, replace driver calls to
drm_modeset_lock_all() with DRM_MODESET_LOCK_ALL_BEGIN() and
DRM_MODESET_LOCK_ALL_END()

While the previous commit was a simple "search and replace", this time I
had to do a bit of refactoring as only one call to
DRM_MODESET_LOCK_ALL_BEGIN() is allowed inside one same function.
Signed-off-by: Fernando Ramos <greenfoo@u92.eu>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20210924064324.229457-14-greenfoo@u92.eu

drivers/gpu/drm/i915/display/intel_overlay.c

@@ -1105,6 +1105,7 @@ int intel_overlay_put_image_ioctl(struct drm_device *dev, void *data,
 	struct drm_crtc *drmmode_crtc;
 	struct intel_crtc *crtc;
 	struct drm_i915_gem_object *new_bo;
+	struct drm_modeset_acquire_ctx ctx;
 	int ret;
 
 	overlay = dev_priv->overlay;
@@ -1113,24 +1114,24 @@ int intel_overlay_put_image_ioctl(struct drm_device *dev, void *data,
 		return -ENODEV;
 	}
 
-	if (!(params->flags & I915_OVERLAY_ENABLE)) {
-		drm_modeset_lock_all(dev);
-		ret = intel_overlay_switch_off(overlay);
-		drm_modeset_unlock_all(dev);
+	if (params->flags & I915_OVERLAY_ENABLE) {
 
-		return ret;
-	}
+		drmmode_crtc = drm_crtc_find(dev, file_priv, params->crtc_id);
+		if (!drmmode_crtc)
+			return -ENOENT;
+		crtc = to_intel_crtc(drmmode_crtc);
 
-	drmmode_crtc = drm_crtc_find(dev, file_priv, params->crtc_id);
-	if (!drmmode_crtc)
-		return -ENOENT;
-	crtc = to_intel_crtc(drmmode_crtc);
+		new_bo = i915_gem_object_lookup(file_priv, params->bo_handle);
+		if (!new_bo)
+			return -ENOENT;
+	}
 
-	new_bo = i915_gem_object_lookup(file_priv, params->bo_handle);
-	if (!new_bo)
-		return -ENOENT;
+	DRM_MODESET_LOCK_ALL_BEGIN(dev, ctx, 0, ret);
 
-	drm_modeset_lock_all(dev);
+	if (!(params->flags & I915_OVERLAY_ENABLE)) {
+		ret = intel_overlay_switch_off(overlay);
+		goto out_unlock;
+	}
 
 	if (i915_gem_object_is_tiled(new_bo)) {
 		drm_dbg_kms(&dev_priv->drm,
@@ -1195,14 +1196,11 @@ int intel_overlay_put_image_ioctl(struct drm_device *dev, void *data,
 	if (ret != 0)
 		goto out_unlock;
 
-	drm_modeset_unlock_all(dev);
-	i915_gem_object_put(new_bo);
-
-	return 0;
-
 out_unlock:
-	drm_modeset_unlock_all(dev);
-	i915_gem_object_put(new_bo);
+	DRM_MODESET_LOCK_ALL_END(dev, ctx, ret);
+
+	if (params->flags & I915_OVERLAY_ENABLE)
+		i915_gem_object_put(new_bo);
 
 	return ret;
 }