drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c

Source file repositories/reference/linux-study-clean/drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c

File Facts

System
Linux kernel
Corpus path
drivers/gpu/drm/i915/gem/selftests/huge_gem_object.c
Extension
.c
Size
2936 bytes
Lines
132
Domain
Driver Families
Bucket
drivers/gpu
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (!page) {
			sg_mark_end(sg);
			goto err;
		}

		sg_set_page(sg, page, PAGE_SIZE, 0);
		sg = __sg_next(sg);
	}
	if (nreal < npages) {
		for (end = sg, src = pages->sgl; sg; sg = __sg_next(sg)) {
			sg_set_page(sg, sg_page(src), PAGE_SIZE, 0);
			src = __sg_next(src);
			if (src == end)
				src = pages->sgl;
		}
	}

	if (i915_gem_gtt_prepare_pages(obj, pages))
		goto err;

	__i915_gem_object_set_pages(obj, pages);

	return 0;

err:
	huge_free_pages(obj, pages);
	return -ENOMEM;
#undef GFP
}

static void huge_put_pages(struct drm_i915_gem_object *obj,
			   struct sg_table *pages)
{
	i915_gem_gtt_finish_pages(obj, pages);
	huge_free_pages(obj, pages);

	obj->mm.dirty = false;
}

static const struct drm_i915_gem_object_ops huge_ops = {
	.name = "huge-gem",
	.get_pages = huge_get_pages,
	.put_pages = huge_put_pages,
};

struct drm_i915_gem_object *
huge_gem_object(struct drm_i915_private *i915,
		phys_addr_t phys_size,
		dma_addr_t dma_size)
{
	static struct lock_class_key lock_class;
	struct drm_i915_gem_object *obj;
	unsigned int cache_level;

	GEM_BUG_ON(!phys_size || phys_size > dma_size);
	GEM_BUG_ON(!IS_ALIGNED(phys_size, PAGE_SIZE));
	GEM_BUG_ON(!IS_ALIGNED(dma_size, I915_GTT_PAGE_SIZE));

	if (overflows_type(dma_size, obj->base.size))
		return ERR_PTR(-E2BIG);

	obj = i915_gem_object_alloc();
	if (!obj)
		return ERR_PTR(-ENOMEM);

	drm_gem_private_object_init(&i915->drm, &obj->base, dma_size);
	i915_gem_object_init(obj, &huge_ops, &lock_class, 0);
	obj->mem_flags |= I915_BO_FLAG_STRUCT_PAGE;

	obj->read_domains = I915_GEM_DOMAIN_CPU;
	obj->write_domain = I915_GEM_DOMAIN_CPU;
	cache_level = HAS_LLC(i915) ? I915_CACHE_LLC : I915_CACHE_NONE;
	i915_gem_object_set_cache_coherency(obj, cache_level);
	obj->scratch = phys_size;

	return obj;
}

Annotation

Implementation Notes