swsusp: use inline functions for changing page flags

Replace direct invocations of SetPageNosave(), SetPageNosaveFree() etc.  with
calls to inline functions that can be changed in subsequent patches without
modifying the code calling them.
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/suspend.h

@@ -8,6 +8,7 @@
 #include <linux/notifier.h>
 #include <linux/init.h>
 #include <linux/pm.h>
+#include <linux/mm.h>
 
 /* struct pbe is used for creating lists of pages that should be restored
  * atomically during the resume from disk, because the page frames they have
@@ -49,6 +50,38 @@ void __save_processor_state(struct saved_context *ctxt);
 void __restore_processor_state(struct saved_context *ctxt);
 unsigned long get_safe_page(gfp_t gfp_mask);
 
+/* Page management functions for the software suspend (swsusp) */
+
+static inline void swsusp_set_page_forbidden(struct page *page)
+{
+	SetPageNosave(page);
+}
+
+static inline int swsusp_page_is_forbidden(struct page *page)
+{
+	return PageNosave(page);
+}
+
+static inline void swsusp_unset_page_forbidden(struct page *page)
+{
+	ClearPageNosave(page);
+}
+
+static inline void swsusp_set_page_free(struct page *page)
+{
+	SetPageNosaveFree(page);
+}
+
+static inline int swsusp_page_is_free(struct page *page)
+{
+	return PageNosaveFree(page);
+}
+
+static inline void swsusp_unset_page_free(struct page *page)
+{
+	ClearPageNosaveFree(page);
+}
+
 /*
  * XXX: We try to keep some more pages free so that I/O operations succeed
  * without paging. Might this be more?

kernel/power/snapshot.c

@@ -67,15 +67,15 @@ static void *get_image_page(gfp_t gfp_mask, int safe_needed)
 
 	res = (void *)get_zeroed_page(gfp_mask);
 	if (safe_needed)
-		while (res && PageNosaveFree(virt_to_page(res))) {
+		while (res && swsusp_page_is_free(virt_to_page(res))) {
 			/* The page is unsafe, mark it for swsusp_free() */
-			SetPageNosave(virt_to_page(res));
+			swsusp_set_page_forbidden(virt_to_page(res));
 			allocated_unsafe_pages++;
 			res = (void *)get_zeroed_page(gfp_mask);
 		}
 	if (res) {
-		SetPageNosave(virt_to_page(res));
-		SetPageNosaveFree(virt_to_page(res));
+		swsusp_set_page_forbidden(virt_to_page(res));
+		swsusp_set_page_free(virt_to_page(res));
 	}
 	return res;
 }
@@ -91,8 +91,8 @@ static struct page *alloc_image_page(gfp_t gfp_mask)
 
 	page = alloc_page(gfp_mask);
 	if (page) {
-		SetPageNosave(page);
-		SetPageNosaveFree(page);
+		swsusp_set_page_forbidden(page);
+		swsusp_set_page_free(page);
 	}
 	return page;
 }
@@ -110,9 +110,9 @@ static inline void free_image_page(void *addr, int clear_nosave_free)
 
 	page = virt_to_page(addr);
 
-	ClearPageNosave(page);
+	swsusp_unset_page_forbidden(page);
 	if (clear_nosave_free)
-		ClearPageNosaveFree(page);
+		swsusp_unset_page_free(page);
 
 	__free_page(page);
 }
@@ -615,7 +615,8 @@ static struct page *saveable_highmem_page(unsigned long pfn)
 
 	BUG_ON(!PageHighMem(page));
 
-	if (PageNosave(page) || PageReserved(page) || PageNosaveFree(page))
+	if (swsusp_page_is_forbidden(page) ||  swsusp_page_is_free(page) ||
+	    PageReserved(page))
 		return NULL;
 
 	return page;
@@ -670,7 +671,7 @@ static struct page *saveable_page(unsigned long pfn)
 
 	BUG_ON(PageHighMem(page));
 
-	if (PageNosave(page) || PageNosaveFree(page))
+	if (swsusp_page_is_forbidden(page) || swsusp_page_is_free(page))
 		return NULL;
 
 	if (PageReserved(page) && pfn_is_nosave(pfn))
@@ -810,9 +811,10 @@ void swsusp_free(void)
 			if (pfn_valid(pfn)) {
 				struct page *page = pfn_to_page(pfn);
 
-				if (PageNosave(page) && PageNosaveFree(page)) {
-					ClearPageNosave(page);
-					ClearPageNosaveFree(page);
+				if (swsusp_page_is_forbidden(page) &&
+				    swsusp_page_is_free(page)) {
+					swsusp_unset_page_forbidden(page);
+					swsusp_unset_page_free(page);
 					__free_page(page);
 				}
 			}
@@ -1135,7 +1137,7 @@ static int mark_unsafe_pages(struct memory_bitmap *bm)
 		max_zone_pfn = zone->zone_start_pfn + zone->spanned_pages;
 		for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
 			if (pfn_valid(pfn))
-				ClearPageNosaveFree(pfn_to_page(pfn));
+				swsusp_unset_page_free(pfn_to_page(pfn));
 	}
 
 	/* Mark pages that correspond to the "original" pfns as "unsafe" */
@@ -1144,7 +1146,7 @@ static int mark_unsafe_pages(struct memory_bitmap *bm)
 		pfn = memory_bm_next_pfn(bm);
 		if (likely(pfn != BM_END_OF_MAP)) {
 			if (likely(pfn_valid(pfn)))
-				SetPageNosaveFree(pfn_to_page(pfn));
+				swsusp_set_page_free(pfn_to_page(pfn));
 			else
 				return -EFAULT;
 		}
@@ -1310,14 +1312,14 @@ prepare_highmem_image(struct memory_bitmap *bm, unsigned int *nr_highmem_p)
 		struct page *page;
 
 		page = alloc_page(__GFP_HIGHMEM);
-		if (!PageNosaveFree(page)) {
+		if (!swsusp_page_is_free(page)) {
 			/* The page is "safe", set its bit the bitmap */
 			memory_bm_set_bit(bm, page_to_pfn(page));
 			safe_highmem_pages++;
 		}
 		/* Mark the page as allocated */
-		SetPageNosave(page);
-		SetPageNosaveFree(page);
+		swsusp_set_page_forbidden(page);
+		swsusp_set_page_free(page);
 	}
 	memory_bm_position_reset(bm);
 	safe_highmem_bm = bm;
@@ -1349,7 +1351,7 @@ get_highmem_page_buffer(struct page *page, struct chain_allocator *ca)
 	struct highmem_pbe *pbe;
 	void *kaddr;
 
-	if (PageNosave(page) && PageNosaveFree(page)) {
+	if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page)) {
 		/* We have allocated the "original" page frame and we can
 		 * use it directly to store the loaded page.
 		 */
@@ -1511,14 +1513,14 @@ prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm)
 			error = -ENOMEM;
 			goto Free;
 		}
-		if (!PageNosaveFree(virt_to_page(lp))) {
+		if (!swsusp_page_is_free(virt_to_page(lp))) {
 			/* The page is "safe", add it to the list */
 			lp->next = safe_pages_list;
 			safe_pages_list = lp;
 		}
 		/* Mark the page as allocated */
-		SetPageNosave(virt_to_page(lp));
-		SetPageNosaveFree(virt_to_page(lp));
+		swsusp_set_page_forbidden(virt_to_page(lp));
+		swsusp_set_page_free(virt_to_page(lp));
 		nr_pages--;
 	}
 	/* Free the reserved safe pages so that chain_alloc() can use them */
@@ -1547,7 +1549,7 @@ static void *get_buffer(struct memory_bitmap *bm, struct chain_allocator *ca)
 	if (PageHighMem(page))
 		return get_highmem_page_buffer(page, ca);
 
-	if (PageNosave(page) && PageNosaveFree(page))
+	if (swsusp_page_is_forbidden(page) && swsusp_page_is_free(page))
 		/* We have allocated the "original" page frame and we can
 		 * use it directly to store the loaded page.
 		 */

mm/page_alloc.c

@@ -775,8 +775,8 @@ void mark_free_pages(struct zone *zone)
 		if (pfn_valid(pfn)) {
 			struct page *page = pfn_to_page(pfn);
 
-			if (!PageNosave(page))
-				ClearPageNosaveFree(page);
+			if (!swsusp_page_is_forbidden(page))
+				swsusp_unset_page_free(page);
 		}
 
 	for (order = MAX_ORDER - 1; order >= 0; --order)
@@ -785,7 +785,7 @@ void mark_free_pages(struct zone *zone)
 
 			pfn = page_to_pfn(list_entry(curr, struct page, lru));
 			for (i = 0; i < (1UL << order); i++)
-				SetPageNosaveFree(pfn_to_page(pfn + i));
+				swsusp_set_page_free(pfn_to_page(pfn + i));
 		}
 
 	spin_unlock_irqrestore(&zone->lock, flags);