1 files changed, 75 insertions, 32 deletions

diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 8bf3770f294e..33dad3fa6043 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -124,6 +124,31 @@ drm_gem_destroy(struct drm_device *dev)
 }
 
 /**
+ * Initialize an already allocate GEM object of the specified size with
+ * shmfs backing store.
+ */
+int drm_gem_object_init(struct drm_device *dev,
+			struct drm_gem_object *obj, size_t size)
+{
+	BUG_ON((size & (PAGE_SIZE - 1)) != 0);
+
+	obj->dev = dev;
+	obj->filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
+	if (IS_ERR(obj->filp))
+		return -ENOMEM;
+
+	kref_init(&obj->refcount);
+	kref_init(&obj->handlecount);
+	obj->size = size;
+
+	atomic_inc(&dev->object_count);
+	atomic_add(obj->size, &dev->object_memory);
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_gem_object_init);
+
+/**
  * Allocate a GEM object of the specified size with shmfs backing store
  */
 struct drm_gem_object *
@@ -131,28 +156,22 @@ drm_gem_object_alloc(struct drm_device *dev, size_t size)
 {
 	struct drm_gem_object *obj;
 
-	BUG_ON((size & (PAGE_SIZE - 1)) != 0);
-
 	obj = kzalloc(sizeof(*obj), GFP_KERNEL);
 	if (!obj)
 		goto free;
 
-	obj->dev = dev;
-	obj->filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
-	if (IS_ERR(obj->filp))
+	if (drm_gem_object_init(dev, obj, size) != 0)
 		goto free;
 
-	kref_init(&obj->refcount);
-	kref_init(&obj->handlecount);
-	obj->size = size;
 	if (dev->driver->gem_init_object != NULL &&
 	    dev->driver->gem_init_object(obj) != 0) {
 		goto fput;
 	}
-	atomic_inc(&dev->object_count);
-	atomic_add(obj->size, &dev->object_memory);
 	return obj;
 fput:
+	/* Object_init mangles the global counters - readjust them. */
+	atomic_dec(&dev->object_count);
+	atomic_sub(obj->size, &dev->object_memory);
 	fput(obj->filp);
 free:
 	kfree(obj);
@@ -192,9 +211,7 @@ drm_gem_handle_delete(struct drm_file *filp, u32 handle)
 	idr_remove(&filp->object_idr, handle);
 	spin_unlock(&filp->table_lock);
 
-	mutex_lock(&dev->struct_mutex);
-	drm_gem_object_handle_unreference(obj);
-	mutex_unlock(&dev->struct_mutex);
+	drm_gem_object_handle_unreference_unlocked(obj);
 
 	return 0;
 }
@@ -325,9 +342,7 @@ again:
 	}
 
 err:
-	mutex_lock(&dev->struct_mutex);
-	drm_gem_object_unreference(obj);
-	mutex_unlock(&dev->struct_mutex);
+	drm_gem_object_unreference_unlocked(obj);
 	return ret;
 }
 
@@ -358,9 +373,7 @@ drm_gem_open_ioctl(struct drm_device *dev, void *data,
 		return -ENOENT;
 
 	ret = drm_gem_handle_create(file_priv, obj, &handle);
-	mutex_lock(&dev->struct_mutex);
-	drm_gem_object_unreference(obj);
-	mutex_unlock(&dev->struct_mutex);
+	drm_gem_object_unreference_unlocked(obj);
 	if (ret)
 		return ret;
 
@@ -390,7 +403,7 @@ drm_gem_object_release_handle(int id, void *ptr, void *data)
 {
 	struct drm_gem_object *obj = ptr;
 
-	drm_gem_object_handle_unreference(obj);
+	drm_gem_object_handle_unreference_unlocked(obj);
 
 	return 0;
 }
@@ -403,16 +416,25 @@ drm_gem_object_release_handle(int id, void *ptr, void *data)
 void
 drm_gem_release(struct drm_device *dev, struct drm_file *file_private)
 {
-	mutex_lock(&dev->struct_mutex);
 	idr_for_each(&file_private->object_idr,
 		     &drm_gem_object_release_handle, NULL);
 
 	idr_destroy(&file_private->object_idr);
-	mutex_unlock(&dev->struct_mutex);
 }
 
+void
+drm_gem_object_release(struct drm_gem_object *obj)
+{
+	struct drm_device *dev = obj->dev;
+	fput(obj->filp);
+	atomic_dec(&dev->object_count);
+	atomic_sub(obj->size, &dev->object_memory);
+}
+EXPORT_SYMBOL(drm_gem_object_release);
+
 /**
  * Called after the last reference to the object has been lost.
+ * Must be called holding struct_ mutex
  *
  * Frees the object
  */
@@ -426,15 +448,37 @@ drm_gem_object_free(struct kref *kref)
 
 	if (dev->driver->gem_free_object != NULL)
 		dev->driver->gem_free_object(obj);
-
-	fput(obj->filp);
-	atomic_dec(&dev->object_count);
-	atomic_sub(obj->size, &dev->object_memory);
-	kfree(obj);
 }
 EXPORT_SYMBOL(drm_gem_object_free);
 
 /**
+ * Called after the last reference to the object has been lost.
+ * Must be called without holding struct_mutex
+ *
+ * Frees the object
+ */
+void
+drm_gem_object_free_unlocked(struct kref *kref)
+{
+	struct drm_gem_object *obj = (struct drm_gem_object *) kref;
+	struct drm_device *dev = obj->dev;
+
+	if (dev->driver->gem_free_object_unlocked != NULL)
+		dev->driver->gem_free_object_unlocked(obj);
+	else if (dev->driver->gem_free_object != NULL) {
+		mutex_lock(&dev->struct_mutex);
+		dev->driver->gem_free_object(obj);
+		mutex_unlock(&dev->struct_mutex);
+	}
+}
+EXPORT_SYMBOL(drm_gem_object_free_unlocked);
+
+static void drm_gem_object_ref_bug(struct kref *list_kref)
+{
+	BUG();
+}
+
+/**
  * Called after the last handle to the object has been closed
  *
  * Removes any name for the object. Note that this must be
@@ -458,8 +502,10 @@ drm_gem_object_handle_free(struct kref *kref)
 		/*
 		 * The object name held a reference to this object, drop
 		 * that now.
+		*
+		* This cannot be the last reference, since the handle holds one too.
 		 */
-		drm_gem_object_unreference(obj);
+		kref_put(&obj->refcount, drm_gem_object_ref_bug);
 	} else
 		spin_unlock(&dev->object_name_lock);
 
@@ -477,11 +523,8 @@ EXPORT_SYMBOL(drm_gem_vm_open);
 void drm_gem_vm_close(struct vm_area_struct *vma)
 {
 	struct drm_gem_object *obj = vma->vm_private_data;
-	struct drm_device *dev = obj->dev;
 
-	mutex_lock(&dev->struct_mutex);
-	drm_gem_object_unreference(obj);
-	mutex_unlock(&dev->struct_mutex);
+	drm_gem_object_unreference_unlocked(obj);
 }
 EXPORT_SYMBOL(drm_gem_vm_close);