diff --git a/include/linux/memblock.h b/include/linux/memblock.h
index 2925da2..5b759c9 100644
--- a/include/linux/memblock.h
+++ b/include/linux/memblock.h
@@ -328,6 +328,7 @@
 phys_addr_t __memblock_alloc_base(phys_addr_t size, phys_addr_t align,
 				  phys_addr_t max_addr);
 phys_addr_t memblock_phys_mem_size(void);
+phys_addr_t memblock_reserved_size(void);
 phys_addr_t memblock_mem_size(unsigned long limit_pfn);
 phys_addr_t memblock_start_of_DRAM(void);
 phys_addr_t memblock_end_of_DRAM(void);