int __remove_pages(struct zone *zone, unsigned long phys_start_pfn,
		 unsigned long nr_pages)
{
	unsigned long i, ret = 0;
	int sections_to_remove;

	/*
	 * We can only remove entire sections
	 */
	BUG_ON(phys_start_pfn & ~PAGE_SECTION_MASK);
	BUG_ON(nr_pages % PAGES_PER_SECTION);

	sections_to_remove = nr_pages / PAGES_PER_SECTION;
	for (i = 0; i < sections_to_remove; i++) {
		unsigned long pfn = phys_start_pfn + i*PAGES_PER_SECTION;
		release_mem_region(pfn << PAGE_SHIFT,
				   PAGES_PER_SECTION << PAGE_SHIFT);
		ret = __remove_section(zone, __pfn_to_section(pfn));
		if (ret)
			break;
	}
	return ret;
}

Unknown