unsigned long __phys_addr(unsigned long x)
{
unsigned long phys_addr = x - PAGE_OFFSET;
/* VMALLOC_* aren't constants */
VIRTUAL_BUG_ON(x < PAGE_OFFSET);
VIRTUAL_BUG_ON(__vmalloc_start_set && is_vmalloc_addr((void *) x));
/* max_low_pfn is set early, but not _that_ early */
if (max_low_pfn) {
VIRTUAL_BUG_ON((phys_addr >> PAGE_SHIFT) > max_low_pfn);
BUG_ON(slow_virt_to_phys((void *)x) != phys_addr);
}
return phys_addr;
}
/*
* Wrapper for slow_virt_to_phys() that handles NULL addresses.
*/
static inline phys_addr_t
virt_to_phys_or_null_size(void *va, unsigned long size)
{
bool bad_size;
if (!va)
return 0;
if (virt_addr_valid(va))
return virt_to_phys(va);
/*
* A fully aligned variable on the stack is guaranteed not to
* cross a page bounary. Try to catch strings on the stack by
* checking that 'size' is a power of two.
*/
bad_size = size > PAGE_SIZE || !is_power_of_2(size);
WARN_ON(!IS_ALIGNED((unsigned long)va, size) || bad_size);
return slow_virt_to_phys(va);
}
