Man page 9 : free_bootmem_with_active_regions

free_bootmem_with_active_regions - Call free_bootmem_node for each active range

void free_bootmem_with_active_regions(int  nid , unsigned long  max_low_pfn );

nid
    The node to free memory on. If MAX_NUMNODES, all nodes are freed.

max_low_pfn
    The highest PFN that will be passed to free_bootmem_node

If an architecture guarantees that all ranges registered with add_active_ranges contain no holes and may be freed, this this function may be used instead of calling free_bootmem manually.