unsigned long
__phys_addr(unsigned long virt_addr)
{
    /* Handle kernel symbols */
    printk("memstart %llx\n",memstart_addr);
    printk("virt_addr %llx\n", virt_addr);
    printk("sizeof %d\n", sizeof(unsigned long));
    printk("start kernel map %llx\n", __START_KERNEL_map);
    printk("PHYS_OFFSET %llx\n", PHYS_OFFSET);
    if (virt_addr >= __START_KERNEL_map)
        return (unsigned long)virt_addr - (unsigned long)__START_KERNEL_map + (unsigned long)PHYS_OFFSET;
    /* Handle kernel data */
    return (unsigned long)virt_addr - (unsigned long)PAGE_OFFSET;
}