drm/gem: simplify object initialization

drm_gem_object_init() and drm_gem_private_object_init() do exactly the
same (except for shmem alloc) so make the first use the latter to reduce
code duplication.

Also drop the return code from drm_gem_private_object_init(). It seems
unlikely that we will extend it any time soon so no reason to keep it
around. This simplifies code paths in drivers, too.

Last but not least, fix gma500 to call drm_gem_object_release() before
freeing objects that were allocated via drm_gem_private_object_init().
That isn't actually necessary for now, but might be in the future.

Signed-off-by: David Herrmann <dh.herrmann@gmail.com>
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Acked-by: Rob Clark <robdclark@gmail.com>
Signed-off-by: Dave Airlie <airlied@gmail.com>
diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c
index 603f256..1ad9e7e 100644
--- a/drivers/gpu/drm/drm_gem.c
+++ b/drivers/gpu/drm/drm_gem.c
@@ -132,16 +132,14 @@
 int drm_gem_object_init(struct drm_device *dev,
 			struct drm_gem_object *obj, size_t size)
 {
-	BUG_ON((size & (PAGE_SIZE - 1)) != 0);
+	struct file *filp;
 
-	obj->dev = dev;
-	obj->filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
-	if (IS_ERR(obj->filp))
-		return PTR_ERR(obj->filp);
+	filp = shmem_file_setup("drm mm object", size, VM_NORESERVE);
+	if (IS_ERR(filp))
+		return PTR_ERR(filp);
 
-	kref_init(&obj->refcount);
-	atomic_set(&obj->handle_count, 0);
-	obj->size = size;
+	drm_gem_private_object_init(dev, obj, size);
+	obj->filp = filp;
 
 	return 0;
 }
@@ -152,8 +150,8 @@
  * no GEM provided backing store. Instead the caller is responsible for
  * backing the object and handling it.
  */
-int drm_gem_private_object_init(struct drm_device *dev,
-			struct drm_gem_object *obj, size_t size)
+void drm_gem_private_object_init(struct drm_device *dev,
+				 struct drm_gem_object *obj, size_t size)
 {
 	BUG_ON((size & (PAGE_SIZE - 1)) != 0);
 
@@ -163,8 +161,6 @@
 	kref_init(&obj->refcount);
 	atomic_set(&obj->handle_count, 0);
 	obj->size = size;
-
-	return 0;
 }
 EXPORT_SYMBOL(drm_gem_private_object_init);
 
diff --git a/drivers/gpu/drm/gma500/framebuffer.c b/drivers/gpu/drm/gma500/framebuffer.c
index 8b1b6d9..362dd2a 100644
--- a/drivers/gpu/drm/gma500/framebuffer.c
+++ b/drivers/gpu/drm/gma500/framebuffer.c
@@ -321,10 +321,8 @@
 	/* Begin by trying to use stolen memory backing */
 	backing = psb_gtt_alloc_range(dev, aligned_size, "fb", 1);
 	if (backing) {
-		if (drm_gem_private_object_init(dev,
-					&backing->gem, aligned_size) == 0)
-			return backing;
-		psb_gtt_free_range(dev, backing);
+		drm_gem_private_object_init(dev, &backing->gem, aligned_size);
+		return backing;
 	}
 	return NULL;
 }
diff --git a/drivers/gpu/drm/gma500/gem.c b/drivers/gpu/drm/gma500/gem.c
index eefd6cc..fe1d332 100644
--- a/drivers/gpu/drm/gma500/gem.c
+++ b/drivers/gpu/drm/gma500/gem.c
@@ -261,11 +261,12 @@
 	struct gtt_range *gtt = psb_gtt_alloc_range(dev, size, "gem", 1);
 	if (gtt == NULL)
 		return -ENOMEM;
-	if (drm_gem_private_object_init(dev, &gtt->gem, size) != 0)
-		goto free_gtt;
+
+	drm_gem_private_object_init(dev, &gtt->gem, size);
 	if (drm_gem_handle_create(file, &gtt->gem, handle) == 0)
 		return 0;
-free_gtt:
+
+	drm_gem_object_release(&gtt->gem);
 	psb_gtt_free_range(dev, gtt);
 	return -ENOMEM;
 }
diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
index dc53a52..f2e185c 100644
--- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c
+++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c
@@ -289,12 +289,7 @@
 		goto fail_detach;
 	}
 
-	ret = drm_gem_private_object_init(dev, &obj->base, dma_buf->size);
-	if (ret) {
-		i915_gem_object_free(obj);
-		goto fail_detach;
-	}
-
+	drm_gem_private_object_init(dev, &obj->base, dma_buf->size);
 	i915_gem_object_init(obj, &i915_gem_object_dmabuf_ops);
 	obj->base.import_attach = attach;
 
diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 5c1a535..5521833 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -291,9 +291,7 @@
 	if (obj == NULL)
 		return NULL;
 
-	if (drm_gem_private_object_init(dev, &obj->base, stolen->size))
-		goto cleanup;
-
+	drm_gem_private_object_init(dev, &obj->base, stolen->size);
 	i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
 
 	obj->pages = i915_pages_create_for_stolen(dev,
diff --git a/drivers/gpu/drm/omapdrm/omap_gem.c b/drivers/gpu/drm/omapdrm/omap_gem.c
index ebbdf41..cbcd71e 100644
--- a/drivers/gpu/drm/omapdrm/omap_gem.c
+++ b/drivers/gpu/drm/omapdrm/omap_gem.c
@@ -1427,8 +1427,9 @@
 		omap_obj->height = gsize.tiled.height;
 	}
 
+	ret = 0;
 	if (flags & (OMAP_BO_DMA|OMAP_BO_EXT_MEM))
-		ret = drm_gem_private_object_init(dev, obj, size);
+		drm_gem_private_object_init(dev, obj, size);
 	else
 		ret = drm_gem_object_init(dev, obj, size);
 
diff --git a/include/drm/drmP.h b/include/drm/drmP.h
index dd03fd4..86f5243 100644
--- a/include/drm/drmP.h
+++ b/include/drm/drmP.h
@@ -1601,8 +1601,8 @@
 					    size_t size);
 int drm_gem_object_init(struct drm_device *dev,
 			struct drm_gem_object *obj, size_t size);
-int drm_gem_private_object_init(struct drm_device *dev,
-			struct drm_gem_object *obj, size_t size);
+void drm_gem_private_object_init(struct drm_device *dev,
+				 struct drm_gem_object *obj, size_t size);
 void drm_gem_object_handle_free(struct drm_gem_object *obj);
 void drm_gem_vm_open(struct vm_area_struct *vma);
 void drm_gem_vm_close(struct vm_area_struct *vma);