x86: move e820_mark_nosave_regions to e820.c

and make e820_mark_nosave_regions to take limit_pfn to use max_low_pfn
for 32bit and end_pfn for 64bit

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/arch/x86/kernel/e820.c b/arch/x86/kernel/e820.c
index 35da8cd..0cd9132 100644
--- a/arch/x86/kernel/e820.c
+++ b/arch/x86/kernel/e820.c
@@ -18,6 +18,7 @@
 #include <linux/module.h>
 #include <linux/mm.h>
 #include <linux/pfn.h>
+#include <linux/suspend.h>
 
 #include <asm/pgtable.h>
 #include <asm/page.h>
@@ -495,6 +496,37 @@
 	       pci_mem_start, gapstart, gapsize);
 }
 
+#if defined(CONFIG_X86_64) || \
+	(defined(CONFIG_X86_32) && defined(CONFIG_HIBERNATION))
+/**
+ * Find the ranges of physical addresses that do not correspond to
+ * e820 RAM areas and mark the corresponding pages as nosave for
+ * hibernation (32 bit) or software suspend and suspend to RAM (64 bit).
+ *
+ * This function requires the e820 map to be sorted and without any
+ * overlapping entries and assumes the first e820 area to be RAM.
+ */
+void __init e820_mark_nosave_regions(unsigned long limit_pfn)
+{
+	int i;
+	unsigned long pfn;
+
+	pfn = PFN_DOWN(e820.map[0].addr + e820.map[0].size);
+	for (i = 1; i < e820.nr_map; i++) {
+		struct e820entry *ei = &e820.map[i];
+
+		if (pfn < PFN_UP(ei->addr))
+			register_nosave_region(pfn, PFN_UP(ei->addr));
+
+		pfn = PFN_DOWN(ei->addr + ei->size);
+		if (ei->type != E820_RAM)
+			register_nosave_region(PFN_UP(ei->addr), pfn);
+
+		if (pfn >= limit_pfn)
+			break;
+	}
+}
+#endif
 
 /*
  * Early reserved memory areas.