memblock: Expose some memblock bits for use by x86

This exposes memblock_debug and associated memblock_dbg() macro,
along with memblock_can_resize so that x86 can use these when
ported to use memblock
Signed-off-by: NYinghai Lu <yinghai@kernel.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

include/linux/memblock.h

@@ -39,6 +39,11 @@ struct memblock {
 };
 
 extern struct memblock memblock;
+extern int memblock_debug;
+extern int memblock_can_resize;
+
+#define memblock_dbg(fmt, ...) \
+	if (memblock_debug) printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__)
 
 extern void __init memblock_init(void);
 extern void __init memblock_analyze(void);

mm/memblock.c

@@ -22,7 +22,8 @@
 
 struct memblock memblock;
 
-static int memblock_debug, memblock_can_resize;
+int memblock_debug;
+int memblock_can_resize;
 static struct memblock_region memblock_memory_init_regions[INIT_MEMBLOCK_REGIONS + 1];
 static struct memblock_region memblock_reserved_init_regions[INIT_MEMBLOCK_REGIONS + 1];