free_area_init_nodes — Initialise all pg_data_t and zone data
| void free_area_init_nodes ( | unsigned long * max_zone_pfn ); | 
   This will call free_area_init_node for each active node in the system.
   Using the page ranges provided by memblock_set_node, the size of each
   zone in each node and their holes is calculated. If the maximum PFN
   between two adjacent zones match, it is assumed that the zone is empty.
   For example, if arch_max_dma_pfn == arch_max_dma32_pfn, it is assumed
   that arch_max_dma32_pfn has no pages. It is also assumed that a zone
   starts where the previous one ended. For example, ZONE_DMA32 starts
   at arch_max_dma_pfn.