drm/i915/stolen: make the object creation interface consistent

Our other backends return an actual error value upon failure. Do the
same for stolen objects, which currently just return NULL on failure.

Signed-off-by: CQ Tang <cq.tang@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004170452.15410-2-matthew.auld@intel.com

1 files changed, 26 insertions, 19 deletions

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
index fad98a921cde..c76260ce13e3 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_stolen.c
@@ -553,10 +553,11 @@ _i915_gem_object_create_stolen(struct drm_i915_private *dev_priv,
 {
 	struct drm_i915_gem_object *obj;
 	unsigned int cache_level;
+	int err = -ENOMEM;
 
 	obj = i915_gem_object_alloc();
-	if (obj == NULL)
-		return NULL;
+	if (!obj)
+		goto err;
 
 	drm_gem_private_object_init(&dev_priv->drm, &obj->base, stolen->size);
 	i915_gem_object_init(obj, &i915_gem_object_stolen_ops);
@@ -566,14 +567,16 @@ _i915_gem_object_create_stolen(struct drm_i915_private *dev_priv,
 	cache_level = HAS_LLC(dev_priv) ? I915_CACHE_LLC : I915_CACHE_NONE;
 	i915_gem_object_set_cache_coherency(obj, cache_level);
 
-	if (i915_gem_object_pin_pages(obj))
+	err = i915_gem_object_pin_pages(obj);
+	if (err)
 		goto cleanup;
 
 	return obj;
 
 cleanup:
 	i915_gem_object_free(obj);
-	return NULL;
+err:
+	return ERR_PTR(err);
 }
 
 struct drm_i915_gem_object *
@@ -585,28 +588,32 @@ i915_gem_object_create_stolen(struct drm_i915_private *dev_priv,
 	int ret;
 
 	if (!drm_mm_initialized(&dev_priv->mm.stolen))
-		return NULL;
+		return ERR_PTR(-ENODEV);
 
 	if (size == 0)
-		return NULL;
+		return ERR_PTR(-EINVAL);
 
 	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 	if (!stolen)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	ret = i915_gem_stolen_insert_node(dev_priv, stolen, size, 4096);
 	if (ret) {
-		kfree(stolen);
-		return NULL;
+		obj = ERR_PTR(ret);
+		goto err_free;
 	}
 
 	obj = _i915_gem_object_create_stolen(dev_priv, stolen);
-	if (obj)
-		return obj;
+	if (IS_ERR(obj))
+		goto err_remove;
 
+	return obj;
+
+err_remove:
 	i915_gem_stolen_remove_node(dev_priv, stolen);
+err_free:
 	kfree(stolen);
-	return NULL;
+	return obj;
 }
 
 struct drm_i915_gem_object *
@@ -622,7 +629,7 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *dev_priv
 	int ret;
 
 	if (!drm_mm_initialized(&dev_priv->mm.stolen))
-		return NULL;
+		return ERR_PTR(-ENODEV);
 
 	DRM_DEBUG_DRIVER("creating preallocated stolen object: stolen_offset=%pa, gtt_offset=%pa, size=%pa\n",
 			 &stolen_offset, &gtt_offset, &size);
@@ -631,11 +638,11 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *dev_priv
 	if (WARN_ON(size == 0) ||
 	    WARN_ON(!IS_ALIGNED(size, I915_GTT_PAGE_SIZE)) ||
 	    WARN_ON(!IS_ALIGNED(stolen_offset, I915_GTT_MIN_ALIGNMENT)))
-		return NULL;
+		return ERR_PTR(-EINVAL);
 
 	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 	if (!stolen)
-		return NULL;
+		return ERR_PTR(-ENOMEM);
 
 	stolen->start = stolen_offset;
 	stolen->size = size;
@@ -645,15 +652,15 @@ i915_gem_object_create_stolen_for_preallocated(struct drm_i915_private *dev_priv
 	if (ret) {
 		DRM_DEBUG_DRIVER("failed to allocate stolen space\n");
 		kfree(stolen);
-		return NULL;
+		return ERR_PTR(ret);
 	}
 
 	obj = _i915_gem_object_create_stolen(dev_priv, stolen);
-	if (obj == NULL) {
+	if (IS_ERR(obj)) {
 		DRM_DEBUG_DRIVER("failed to allocate stolen object\n");
 		i915_gem_stolen_remove_node(dev_priv, stolen);
 		kfree(stolen);
-		return NULL;
+		return obj;
 	}
 
 	/* Some objects just need physical mem from stolen space */
@@ -706,5 +713,5 @@ err_pages:
 	i915_gem_object_unpin_pages(obj);
 err:
 	i915_gem_object_put(obj);
-	return NULL;
+	return ERR_PTR(ret);
 }