unsigned long hugetlb_get_unmapped_area()

in mm/hugetlbpage.c [144:172]

• 23 lines of code
• 7 McCabe index (conditional complexity)

unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
		unsigned long pgoff, unsigned long flags)
{
	struct vm_unmapped_area_info info;

	if (len > RGN_MAP_LIMIT)
		return -ENOMEM;
	if (len & ~HPAGE_MASK)
		return -EINVAL;

	/* Handle MAP_FIXED */
	if (flags & MAP_FIXED) {
		if (prepare_hugepage_range(file, addr, len))
			return -EINVAL;
		return addr;
	}

	/* This code assumes that RGN_HPAGE != 0. */
	if ((REGION_NUMBER(addr) != RGN_HPAGE) || (addr & (HPAGE_SIZE - 1)))
		addr = HPAGE_REGION_BASE;

	info.flags = 0;
	info.length = len;
	info.low_limit = addr;
	info.high_limit = HPAGE_REGION_BASE + RGN_MAP_LIMIT;
	info.align_mask = PAGE_MASK & (HPAGE_SIZE - 1);
	info.align_offset = 0;
	return vm_unmapped_area(&info);
}