The implementation is pretty much similar. There is a -small- added
overhead by having another function call and the address shift.
If that becomes a concern, I suppose we could actually have memblock
itself expose a memblock_pfn_valid() which then ARM can use directly
with an appropriate #define...
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
#ifndef CONFIG_SPARSEMEM
int pfn_valid(unsigned long pfn)
{
- struct memblock_type *mem = &memblock.memory;
- unsigned int left = 0, right = mem->cnt;
-
- do {
- unsigned int mid = (right + left) / 2;
-
- if (pfn < memblock_start_pfn(mem, mid))
- right = mid;
- else if (pfn >= memblock_end_pfn(mem, mid))
- left = mid + 1;
- else
- return 1;
- } while (left < right);
- return 0;
+ return memblock_is_memory(pfn << PAGE_SHIFT);
}
EXPORT_SYMBOL(pfn_valid);