core: Move early_res from arch/x86 to kernel/

This makes the range reservation feature available to other
architectures.

-v2: add get_max_mapped, max_pfn_mapped only defined in x86...
     to fix PPC compiling
-v3: according to hpa, add CONFIG_HAVE_EARLY_RES
-v4: fix typo about EARLY_RES in config

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
LKML-Reference: <4B7B5723.4070009@kernel.org>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/include/linux/early_res.h b/include/linux/early_res.h
new file mode 100644
index 0000000..50f7663
--- /dev/null
+++ b/include/linux/early_res.h
@@ -0,0 +1,22 @@
+#ifndef _LINUX_EARLY_RES_H
+#define _LINUX_EARLY_RES_H
+#ifdef __KERNEL__
+
+extern void reserve_early(u64 start, u64 end, char *name);
+extern void reserve_early_overlap_ok(u64 start, u64 end, char *name);
+extern void free_early(u64 start, u64 end);
+extern void early_res_to_bootmem(u64 start, u64 end);
+
+void reserve_early_without_check(u64 start, u64 end, char *name);
+u64 find_early_area(u64 ei_start, u64 ei_last, u64 start, u64 end,
+			 u64 size, u64 align);
+u64 find_early_area_size(u64 ei_start, u64 ei_last, u64 start,
+			 u64 *sizep, u64 align);
+u64 find_fw_memmap_area(u64 start, u64 end, u64 size, u64 align);
+u64 get_max_mapped(void);
+#include <linux/range.h>
+int get_free_all_memory_range(struct range **rangep, int nodeid);
+
+#endif /* __KERNEL__ */
+
+#endif /* _LINUX_EARLY_RES_H */