The MAX high_addr for `mmap` on PPC64

Hi every one,
    I use the ltp (Linux-Test-Project) and run it on both ppc64 and x86_64.
    There is a code like follows in `ltp/testcase/kernel/mem/hugetbl/hugemmap/hugemmap03.c`:
`code`
        #define HIGH_ADDR       (void *)(0x1000000000000)
	/* Attempt to mmap into highmem addr, should get ENOMEM */
	addr = mmap(HIGH_ADDR, map_sz, PROT_READ,
	            MAP_SHARED | MAP_FIXED, fildes, 0);
`code ends`
    It return ENOMEM on x86_64 as well as we expected. But return EINVAL on ppc64. So I want to know the MAX high addr for PPC64.

-- 
Thanks,
Madper Xie.