int sev_mem_enc_register_region(struct kvm *kvm,
				struct kvm_enc_region *range)
{
	struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
	struct enc_region *region;
	int ret = 0;

	if (!sev_guest(kvm))
		return -ENOTTY;

	/* If kvm is mirroring encryption context it isn't responsible for it */
	if (is_mirroring_enc_context(kvm))
		return -EINVAL;

	if (range->addr > ULONG_MAX || range->size > ULONG_MAX)
		return -EINVAL;

	region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT);
	if (!region)
		return -ENOMEM;

	mutex_lock(&kvm->lock);
	region->pages = sev_pin_memory(kvm, range->addr, range->size, &region->npages, 1);
	if (IS_ERR(region->pages)) {
		ret = PTR_ERR(region->pages);
		mutex_unlock(&kvm->lock);
		goto e_free;
	}

	region->uaddr = range->addr;
	region->size = range->size;

	list_add_tail(&region->list, &sev->regions_list);
	mutex_unlock(&kvm->lock);

	/*
	 * The guest may change the memory encryption attribute from C=0 -> C=1
	 * or vice versa for this memory range. Lets make sure caches are
	 * flushed to ensure that guest data gets written into memory with
	 * correct C-bit.
	 */
	sev_clflush_pages(region->pages, region->npages);

	return ret;

e_free:
	kfree(region);
	return ret;
}
int sev_mem_enc_register_region(struct kvm *kvm,
				struct kvm_enc_region *range)
{
	struct kvm_sev_info *sev = &to_kvm_svm(kvm)->sev_info;
	struct enc_region *region;
	int ret = 0;

	if (!sev_guest(kvm))
		return -ENOTTY;

	 
	if (is_mirroring_enc_context(kvm))
		return -EINVAL;

	if (range->addr > ULONG_MAX || range->size > ULONG_MAX)
		return -EINVAL;

	region = kzalloc(sizeof(*region), GFP_KERNEL_ACCOUNT);
	if (!region)
		return -ENOMEM;

	mutex_lock(&kvm->lock);
	region->pages = sev_pin_memory(kvm, range->addr, range->size, &region->npages, 1);
	if (IS_ERR(region->pages)) {
		ret = PTR_ERR(region->pages);
		mutex_unlock(&kvm->lock);
		goto e_free;
	}

	region->uaddr = range->addr;
	region->size = range->size;

	list_add_tail(&region->list, &sev->regions_list);
	mutex_unlock(&kvm->lock);

	 
	sev_clflush_pages(region->pages, region->npages);

	return ret;

e_free:
	kfree(region);
	return ret;
}