[POWERPC] swsusp: Introduce register_nosave_region_late

This patch introduces a new register_nosave_region_late function that
can be called from initcalls when register_nosave_region can no longer
be used because it uses bootmem.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Acked-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Paul Mackerras <paulus@samba.org>

include/linux/suspend.h

@@ -34,13 +34,22 @@ static inline void pm_restore_console(void) {}
 
 #if defined(CONFIG_PM) && defined(CONFIG_SOFTWARE_SUSPEND)
 /* kernel/power/snapshot.c */
-extern void __init register_nosave_region(unsigned long, unsigned long);
+extern void __register_nosave_region(unsigned long b, unsigned long e, int km);
+static inline void register_nosave_region(unsigned long b, unsigned long e)
+{
+	__register_nosave_region(b, e, 0);
+}
+static inline void register_nosave_region_late(unsigned long b, unsigned long e)
+{
+	__register_nosave_region(b, e, 1);
+}
 extern int swsusp_page_is_forbidden(struct page *);
 extern void swsusp_set_page_free(struct page *);
 extern void swsusp_unset_page_free(struct page *);
 extern unsigned long get_safe_page(gfp_t gfp_mask);
 #else
 static inline void register_nosave_region(unsigned long b, unsigned long e) {}
+static inline void register_nosave_region_late(unsigned long b, unsigned long e) {}
 static inline int swsusp_page_is_forbidden(struct page *p) { return 0; }
 static inline void swsusp_set_page_free(struct page *p) {}
 static inline void swsusp_unset_page_free(struct page *p) {}

kernel/power/snapshot.c

@@ -607,7 +607,8 @@ static LIST_HEAD(nosave_regions);
  */
 
 void __init
-register_nosave_region(unsigned long start_pfn, unsigned long end_pfn)
+__register_nosave_region(unsigned long start_pfn, unsigned long end_pfn,
+			 int use_kmalloc)
 {
 	struct nosave_region *region;
 
@@ -623,8 +624,13 @@ register_nosave_region(unsigned long start_pfn, unsigned long end_pfn)
 			goto Report;
 		}
 	}
-	/* This allocation cannot fail */
-	region = alloc_bootmem_low(sizeof(struct nosave_region));
+	if (use_kmalloc) {
+		/* during init, this shouldn't fail */
+		region = kmalloc(sizeof(struct nosave_region), GFP_KERNEL);
+		BUG_ON(!region);
+	} else
+		/* This allocation cannot fail */
+		region = alloc_bootmem_low(sizeof(struct nosave_region));
 	region->start_pfn = start_pfn;
 	region->end_pfn = end_pfn;
 	list_add_tail(&region->list, &nosave_regions);