drm/i915/region: convert object_create into object_init

Give more flexibility to the caller, if they already have an allocated
object, in case they wish to apply some transformation to the object
prior to handing it over to the region specific initialisation step,
like in gem_create_ext where we would like to first apply the extensions
to the object.

Signed-off-by: Matthew Auld <[e-mail]>
Reviewed-by: Chris Wilson <[e-mail]>
Signed-off-by: Chris Wilson <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

drivers/gpu/drm/i915/gem/i915_gem_lmem.c

···
 					     size, flags);
 }
 
-struct drm_i915_gem_object *
-__i915_gem_lmem_object_create(struct intel_memory_region *mem,
-			      resource_size_t size,
-			      unsigned int flags)
+int __i915_gem_lmem_object_init(struct intel_memory_region *mem,
+				struct drm_i915_gem_object *obj,
+				resource_size_t size,
+				unsigned int flags)
 {
 	static struct lock_class_key lock_class;
 	struct drm_i915_private *i915 = mem->i915;
-	struct drm_i915_gem_object *obj;
-
-	obj = i915_gem_object_alloc();
-	if (!obj)
-		return ERR_PTR(-ENOMEM);
 
 	drm_gem_private_object_init(&i915->drm, &obj->base, size);
 	i915_gem_object_init(obj, &i915_gem_lmem_obj_ops, &lock_class);
···
 
 	i915_gem_object_init_memory_region(obj, mem, flags);
 
-	return obj;
+	return 0;
 }

drivers/gpu/drm/i915/gem/i915_gem_lmem.h

···
 			    resource_size_t size,
 			    unsigned int flags);
 
-struct drm_i915_gem_object *
-__i915_gem_lmem_object_create(struct intel_memory_region *mem,
-			      resource_size_t size,
-			      unsigned int flags);
+int __i915_gem_lmem_object_init(struct intel_memory_region *mem,
+				struct drm_i915_gem_object *obj,
+				resource_size_t size,
+				unsigned int flags);
 
 #endif /* !__I915_GEM_LMEM_H */

drivers/gpu/drm/i915/gem/i915_gem_region.c

···
 			      unsigned int flags)
 {
 	struct drm_i915_gem_object *obj;
+	int err;
 
 	/*
 	 * NB: Our use of resource_size_t for the size stems from using struct
···
 	GEM_BUG_ON(!size);
 	GEM_BUG_ON(!IS_ALIGNED(size, I915_GTT_MIN_ALIGNMENT));
 
+	obj = i915_gem_object_alloc();
+	if (!obj)
+		return ERR_PTR(-ENOMEM);
+
 	/*
 	 * XXX: There is a prevalence of the assumption that we fit the
 	 * object's page count inside a 32bit _signed_ variable. Let's document
···
 	if (overflows_type(size, obj->base.size))
 		return ERR_PTR(-E2BIG);
 
-	obj = mem->ops->create_object(mem, size, flags);
-	if (!IS_ERR(obj))
-		trace_i915_gem_object_create(obj);
+	err = mem->ops->init_object(mem, obj, size, flags);
+	if (err)
+		goto err_object_free;
 
+	trace_i915_gem_object_create(obj);
 	return obj;
+
+err_object_free:
+	i915_gem_object_free(obj);
+	return ERR_PTR(err);
 }

drivers/gpu/drm/i915/gem/i915_gem_shmem.c

···
 	return 0;
 }
 
-static struct drm_i915_gem_object *
-create_shmem(struct intel_memory_region *mem,
-	     resource_size_t size,
-	     unsigned int flags)
+static int shmem_object_init(struct intel_memory_region *mem,
+			     struct drm_i915_gem_object *obj,
+			     resource_size_t size,
+			     unsigned int flags)
 {
 	static struct lock_class_key lock_class;
 	struct drm_i915_private *i915 = mem->i915;
-	struct drm_i915_gem_object *obj;
 	struct address_space *mapping;
 	unsigned int cache_level;
 	gfp_t mask;
 	int ret;
 
-	obj = i915_gem_object_alloc();
-	if (!obj)
-		return ERR_PTR(-ENOMEM);
-
 	ret = __create_shmem(i915, &obj->base, size);
 	if (ret)
-		goto fail;
+		return ret;
 
 	mask = GFP_HIGHUSER | __GFP_RECLAIMABLE;
 	if (IS_I965GM(i915) || IS_I965G(i915)) {
···
 
 	i915_gem_object_init_memory_region(obj, mem, 0);
 
-	return obj;
-
-fail:
-	i915_gem_object_free(obj);
-	return ERR_PTR(ret);
+	return 0;
 }
 
 struct drm_i915_gem_object *
···
 static const struct intel_memory_region_ops shmem_region_ops = {
 	.init = init_shmem,
 	.release = release_shmem,
-	.create_object = create_shmem,
+	.init_object = shmem_object_init,
 };
 
 struct intel_memory_region *i915_gem_shmem_setup(struct drm_i915_private *i915)

drivers/gpu/drm/i915/gem/i915_gem_stolen.c

···
 	.release = i915_gem_object_release_stolen,
 };
 
-static struct drm_i915_gem_object *
-__i915_gem_object_create_stolen(struct intel_memory_region *mem,
-				struct drm_mm_node *stolen)
+int __i915_gem_object_create_stolen(struct intel_memory_region *mem,
+				    struct drm_i915_gem_object *obj,
+				    struct drm_mm_node *stolen)
 {
 	static struct lock_class_key lock_class;
-	struct drm_i915_gem_object *obj;
 	unsigned int cache_level;
-	int err = -ENOMEM;
-
-	obj = i915_gem_object_alloc();
-	if (!obj)
-		goto err;
+	int err;
 
 	drm_gem_private_object_init(&mem->i915->drm, &obj->base, stolen->size);
 	i915_gem_object_init(obj, &i915_gem_object_stolen_ops, &lock_class);
···
 
 	err = i915_gem_object_pin_pages(obj);
 	if (err)
-		goto cleanup;
+		return err;
 
 	i915_gem_object_init_memory_region(obj, mem, 0);
 
-	return obj;
-
-cleanup:
-	i915_gem_object_free(obj);
-err:
-	return ERR_PTR(err);
+	return 0;
 }
 
-static struct drm_i915_gem_object *
-_i915_gem_object_create_stolen(struct intel_memory_region *mem,
-			       resource_size_t size,
-			       unsigned int flags)
+int _i915_gem_object_stolen_init(struct intel_memory_region *mem,
+				 struct drm_i915_gem_object *obj,
+				 resource_size_t size,
+				 unsigned int flags)
 {
 	struct drm_i915_private *i915 = mem->i915;
-	struct drm_i915_gem_object *obj;
 	struct drm_mm_node *stolen;
 	int ret;
 
 	if (!drm_mm_initialized(&i915->mm.stolen))
-		return ERR_PTR(-ENODEV);
+		return -ENODEV;
 
 	if (size == 0)
-		return ERR_PTR(-EINVAL);
+		return -EINVAL;
 
 	stolen = kzalloc(sizeof(*stolen), GFP_KERNEL);
 	if (!stolen)
-		return ERR_PTR(-ENOMEM);
+		return -ENOMEM;
 
 	ret = i915_gem_stolen_insert_node(i915, stolen, size, 4096);
-	if (ret) {
-		obj = ERR_PTR(ret);
+	if (ret)
 		goto err_free;
-	}
 
-	obj = __i915_gem_object_create_stolen(mem, stolen);
-	if (IS_ERR(obj))
+	ret = __i915_gem_object_create_stolen(mem, obj, stolen);
+	if (ret)
 		goto err_remove;
 
-	return obj;
+	return 0;
 
 err_remove:
 	i915_gem_stolen_remove_node(i915, stolen);
 err_free:
 	kfree(stolen);
-	return obj;
+	return ret;
 }
 
 struct drm_i915_gem_object *
···
 static const struct intel_memory_region_ops i915_region_stolen_ops = {
 	.init = init_stolen,
 	.release = release_stolen,
-	.create_object = _i915_gem_object_create_stolen,
+	.init_object = _i915_gem_object_stolen_init,
 };
 
 struct intel_memory_region *i915_gem_stolen_setup(struct drm_i915_private *i915)
···
 		goto err_free;
 	}
 
-	obj = __i915_gem_object_create_stolen(mem, stolen);
-	if (IS_ERR(obj))
+	obj = i915_gem_object_alloc();
+	if (!obj) {
+		obj = ERR_PTR(-ENOMEM);
 		goto err_stolen;
+	}
+
+	ret = __i915_gem_object_create_stolen(mem, obj, stolen);
+	if (ret) {
+		obj = ERR_PTR(ret);
+		goto err_object_free;
+	}
 
 	i915_gem_object_set_cache_coherency(obj, I915_CACHE_NONE);
 	return obj;
 
+err_object_free:
+	i915_gem_object_free(obj);
 err_stolen:
 	i915_gem_stolen_remove_node(i915, stolen);
 err_free:

drivers/gpu/drm/i915/gt/intel_region_lmem.c

···
 static const struct intel_memory_region_ops intel_region_lmem_ops = {
 	.init = region_lmem_init,
 	.release = region_lmem_release,
-	.create_object = __i915_gem_lmem_object_create,
+	.init_object = __i915_gem_lmem_object_init,
 };
 
 struct intel_memory_region *

drivers/gpu/drm/i915/intel_memory_region.h

···
 	int (*init)(struct intel_memory_region *mem);
 	void (*release)(struct intel_memory_region *mem);
 
-	struct drm_i915_gem_object *
-	(*create_object)(struct intel_memory_region *mem,
-			 resource_size_t size,
-			 unsigned int flags);
+	int (*init_object)(struct intel_memory_region *mem,
+			   struct drm_i915_gem_object *obj,
+			   resource_size_t size,
+			   unsigned int flags);
 };
 
 struct intel_memory_region {

drivers/gpu/drm/i915/selftests/mock_region.c

···
 	.release = i915_gem_object_release_memory_region,
 };
 
-static struct drm_i915_gem_object *
-mock_object_create(struct intel_memory_region *mem,
-		   resource_size_t size,
-		   unsigned int flags)
+static int mock_object_init(struct intel_memory_region *mem,
+			    struct drm_i915_gem_object *obj,
+			    resource_size_t size,
+			    unsigned int flags)
 {
 	static struct lock_class_key lock_class;
 	struct drm_i915_private *i915 = mem->i915;
-	struct drm_i915_gem_object *obj;
 
 	if (size > mem->mm.size)
-		return ERR_PTR(-E2BIG);
-
-	obj = i915_gem_object_alloc();
-	if (!obj)
-		return ERR_PTR(-ENOMEM);
+		return -E2BIG;
 
 	drm_gem_private_object_init(&i915->drm, &obj->base, size);
 	i915_gem_object_init(obj, &mock_region_obj_ops, &lock_class);
···
 
 	i915_gem_object_init_memory_region(obj, mem, flags);
 
-	return obj;
+	return 0;
 }
 
 static const struct intel_memory_region_ops mock_region_ops = {
 	.init = intel_memory_region_init_buddy,
 	.release = intel_memory_region_release_buddy,
-	.create_object = mock_object_create,
+	.init_object = mock_object_init,
 };
 
 struct intel_memory_region *