1 files changed, 57 insertions, 23 deletions

diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
index 36c5629af7..888aadb6a4 100644
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -394,6 +394,31 @@ static void drm_mode_rmfb_work_fn(struct work_struct *w)
 	}
 }
 
+static int drm_mode_closefb(struct drm_framebuffer *fb,
+			    struct drm_file *file_priv)
+{
+	struct drm_framebuffer *fbl;
+	bool found = false;
+
+	mutex_lock(&file_priv->fbs_lock);
+	list_for_each_entry(fbl, &file_priv->fbs, filp_head)
+		if (fb == fbl)
+			found = true;
+
+	if (!found) {
+		mutex_unlock(&file_priv->fbs_lock);
+		return -ENOENT;
+	}
+
+	list_del_init(&fb->filp_head);
+	mutex_unlock(&file_priv->fbs_lock);
+
+	/* Drop the reference that was stored in the fbs list */
+	drm_framebuffer_put(fb);
+
+	return 0;
+}
+
 /**
  * drm_mode_rmfb - remove an FB from the configuration
  * @dev: drm device
@@ -410,9 +435,8 @@ static void drm_mode_rmfb_work_fn(struct work_struct *w)
 int drm_mode_rmfb(struct drm_device *dev, u32 fb_id,
 		  struct drm_file *file_priv)
 {
-	struct drm_framebuffer *fb = NULL;
-	struct drm_framebuffer *fbl = NULL;
-	int found = 0;
+	struct drm_framebuffer *fb;
+	int ret;
 
 	if (!drm_core_check_feature(dev, DRIVER_MODESET))
 		return -EOPNOTSUPP;
@@ -421,24 +445,13 @@ int drm_mode_rmfb(struct drm_device *dev, u32 fb_id,
 	if (!fb)
 		return -ENOENT;
 
-	mutex_lock(&file_priv->fbs_lock);
-	list_for_each_entry(fbl, &file_priv->fbs, filp_head)
-		if (fb == fbl)
-			found = 1;
-	if (!found) {
-		mutex_unlock(&file_priv->fbs_lock);
-		goto fail_unref;
+	ret = drm_mode_closefb(fb, file_priv);
+	if (ret != 0) {
+		drm_framebuffer_put(fb);
+		return ret;
 	}
 
-	list_del_init(&fb->filp_head);
-	mutex_unlock(&file_priv->fbs_lock);
-
-	/* drop the reference we picked up in framebuffer lookup */
-	drm_framebuffer_put(fb);
-
 	/*
-	 * we now own the reference that was stored in the fbs list
-	 *
 	 * drm_framebuffer_remove may fail with -EINTR on pending signals,
 	 * so run this in a separate stack as there's no way to correctly
 	 * handle this after the fb is already removed from the lookup table.
@@ -448,6 +461,7 @@ int drm_mode_rmfb(struct drm_device *dev, u32 fb_id,
 
 		INIT_WORK_ONSTACK(&arg.work, drm_mode_rmfb_work_fn);
 		INIT_LIST_HEAD(&arg.fbs);
+		drm_WARN_ON(dev, !list_empty(&fb->filp_head));
 		list_add_tail(&fb->filp_head, &arg.fbs);
 
 		schedule_work(&arg.work);
@@ -457,10 +471,6 @@ int drm_mode_rmfb(struct drm_device *dev, u32 fb_id,
 		drm_framebuffer_put(fb);
 
 	return 0;
-
-fail_unref:
-	drm_framebuffer_put(fb);
-	return -ENOENT;
 }
 
 int drm_mode_rmfb_ioctl(struct drm_device *dev,
@@ -471,6 +481,28 @@ int drm_mode_rmfb_ioctl(struct drm_device *dev,
 	return drm_mode_rmfb(dev, *fb_id, file_priv);
 }
 
+int drm_mode_closefb_ioctl(struct drm_device *dev,
+			   void *data, struct drm_file *file_priv)
+{
+	struct drm_mode_closefb *r = data;
+	struct drm_framebuffer *fb;
+	int ret;
+
+	if (!drm_core_check_feature(dev, DRIVER_MODESET))
+		return -EOPNOTSUPP;
+
+	if (r->pad)
+		return -EINVAL;
+
+	fb = drm_framebuffer_lookup(dev, file_priv, r->fb_id);
+	if (!fb)
+		return -ENOENT;
+
+	ret = drm_mode_closefb(fb, file_priv);
+	drm_framebuffer_put(fb);
+	return ret;
+}
+
 /**
  * drm_mode_getfb - get FB info
  * @dev: drm device for the ioctl
@@ -796,6 +828,8 @@ void drm_framebuffer_free(struct kref *kref)
 			container_of(kref, struct drm_framebuffer, base.refcount);
 	struct drm_device *dev = fb->dev;
 
+	drm_WARN_ON(dev, !list_empty(&fb->filp_head));
+
 	/*
 	 * The lookup idr holds a weak reference, which has not necessarily been
 	 * removed at this point. Check for that.
@@ -1088,7 +1122,7 @@ void drm_framebuffer_remove(struct drm_framebuffer *fb)
 
 	dev = fb->dev;
 
-	WARN_ON(!list_empty(&fb->filp_head));
+	drm_WARN_ON(dev, !list_empty(&fb->filp_head));
 
 	/*
 	 * drm ABI mandates that we remove any deleted framebuffers from active