Revert "swsusp special saveable pages support" commits

This reverts commits

  3e3318dee0 [PATCH] swsusp: x86_64 mark special saveable/unsaveable pages
  b6370d96e0 [PATCH] swsusp: i386 mark special saveable/unsaveable pages
  ce4ab0012b [PATCH] swsusp: add architecture special saveable pages support

because not only do they apparently cause page faults on x86, the
infrastructure doesn't compile on powerpc.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>

kernel/power/power.h

@@ -105,10 +105,6 @@ extern struct bitmap_page *alloc_bitmap(unsigned int nr_bits);
 extern unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap);
 extern void free_all_swap_pages(int swap, struct bitmap_page *bitmap);
 
-extern unsigned int count_special_pages(void);
-extern int save_special_mem(void);
-extern int restore_special_mem(void);
-
 extern int swsusp_check(void);
 extern int swsusp_shrink_memory(void);
 extern void swsusp_free(void);

kernel/power/snapshot.c

@@ -39,90 +39,8 @@ static unsigned int nr_copy_pages;
 static unsigned int nr_meta_pages;
 static unsigned long *buffer;
 
-struct arch_saveable_page {
-	unsigned long start;
-	unsigned long end;
-	char *data;
-	struct arch_saveable_page *next;
-};
-static struct arch_saveable_page *arch_pages;
-
-int swsusp_add_arch_pages(unsigned long start, unsigned long end)
-{
-	struct arch_saveable_page *tmp;
-
-	while (start < end) {
-		tmp = kzalloc(sizeof(struct arch_saveable_page), GFP_KERNEL);
-		if (!tmp)
-			return -ENOMEM;
-		tmp->start = start;
-		tmp->end = ((start >> PAGE_SHIFT) + 1) << PAGE_SHIFT;
-		if (tmp->end > end)
-			tmp->end = end;
-		tmp->next = arch_pages;
-		start = tmp->end;
-		arch_pages = tmp;
-	}
-	return 0;
-}
-
-static unsigned int count_arch_pages(void)
-{
-	unsigned int count = 0;
-	struct arch_saveable_page *tmp = arch_pages;
-	while (tmp) {
-		count++;
-		tmp = tmp->next;
-	}
-	return count;
-}
-
-static int save_arch_mem(void)
-{
-	char *kaddr;
-	struct arch_saveable_page *tmp = arch_pages;
-	int offset;
-
-	pr_debug("swsusp: Saving arch specific memory");
-	while (tmp) {
-		tmp->data = (char *)__get_free_page(GFP_ATOMIC);
-		if (!tmp->data)
-			return -ENOMEM;
-		offset = tmp->start - (tmp->start & PAGE_MASK);
-		/* arch pages might haven't a 'struct page' */
-		kaddr = kmap_atomic_pfn(tmp->start >> PAGE_SHIFT, KM_USER0);
-		memcpy(tmp->data + offset, kaddr + offset,
-			tmp->end - tmp->start);
-		kunmap_atomic(kaddr, KM_USER0);
-
-		tmp = tmp->next;
-	}
-	return 0;
-}
-
-static int restore_arch_mem(void)
-{
-	char *kaddr;
-	struct arch_saveable_page *tmp = arch_pages;
-	int offset;
-
-	while (tmp) {
-		if (!tmp->data)
-			continue;
-		offset = tmp->start - (tmp->start & PAGE_MASK);
-		kaddr = kmap_atomic_pfn(tmp->start >> PAGE_SHIFT, KM_USER0);
-		memcpy(kaddr + offset, tmp->data + offset,
-			tmp->end - tmp->start);
-		kunmap_atomic(kaddr, KM_USER0);
-		free_page((long)tmp->data);
-		tmp->data = NULL;
-		tmp = tmp->next;
-	}
-	return 0;
-}
-
 #ifdef CONFIG_HIGHMEM
-static unsigned int count_highmem_pages(void)
+unsigned int count_highmem_pages(void)
 {
 	struct zone *zone;
 	unsigned long zone_pfn;
@@ -199,7 +117,7 @@ static int save_highmem_zone(struct zone *zone)
 	return 0;
 }
 
-static int save_highmem(void)
+int save_highmem(void)
 {
 	struct zone *zone;
 	int res = 0;
@@ -216,7 +134,7 @@ static int save_highmem(void)
 	return 0;
 }
 
-static int restore_highmem(void)
+int restore_highmem(void)
 {
 	printk("swsusp: Restoring Highmem\n");
 	while (highmem_copy) {
@@ -238,29 +156,6 @@ static inline int save_highmem(void) {return 0;}
 static inline int restore_highmem(void) {return 0;}
 #endif
 
-unsigned int count_special_pages(void)
-{
-	return count_arch_pages() + count_highmem_pages();
-}
-
-int save_special_mem(void)
-{
-	int ret;
-	ret = save_arch_mem();
-	if (!ret)
-		ret = save_highmem();
-	return ret;
-}
-
-int restore_special_mem(void)
-{
-	int ret;
-	ret = restore_arch_mem();
-	if (!ret)
-		ret = restore_highmem();
-	return ret;
-}
-
 static int pfn_is_nosave(unsigned long pfn)
 {
 	unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
@@ -286,6 +181,7 @@ static int saveable(struct zone *zone, unsigned long *zone_pfn)
 		return 0;
 
 	page = pfn_to_page(pfn);
+	BUG_ON(PageReserved(page) && PageNosave(page));
 	if (PageNosave(page))
 		return 0;
 	if (PageReserved(page) && pfn_is_nosave(pfn))

kernel/power/swsusp.c

@@ -62,6 +62,16 @@ unsigned long image_size = 500 * 1024 * 1024;
 
 int in_suspend __nosavedata = 0;
 
+#ifdef CONFIG_HIGHMEM
+unsigned int count_highmem_pages(void);
+int save_highmem(void);
+int restore_highmem(void);
+#else
+static inline int save_highmem(void) { return 0; }
+static inline int restore_highmem(void) { return 0; }
+static inline unsigned int count_highmem_pages(void) { return 0; }
+#endif
+
 /**
  *	The following functions are used for tracing the allocated
  *	swap pages, so that they can be freed in case of an error.
@@ -182,7 +192,7 @@ int swsusp_shrink_memory(void)
 
 	printk("Shrinking memory...  ");
 	do {
-		size = 2 * count_special_pages();
+		size = 2 * count_highmem_pages();
 		size += size / 50 + count_data_pages();
 		size += (size + PBES_PER_PAGE - 1) / PBES_PER_PAGE +
 			PAGES_FOR_IO;
@@ -226,7 +236,7 @@ int swsusp_suspend(void)
 		goto Enable_irqs;
 	}
 
-	if ((error = save_special_mem())) {
+	if ((error = save_highmem())) {
 		printk(KERN_ERR "swsusp: Not enough free pages for highmem\n");
 		goto Restore_highmem;
 	}
@@ -237,7 +247,7 @@ int swsusp_suspend(void)
 	/* Restore control flow magically appears here */
 	restore_processor_state();
 Restore_highmem:
-	restore_special_mem();
+	restore_highmem();
 	device_power_up();
 Enable_irqs:
 	local_irq_enable();
@@ -263,7 +273,7 @@ int swsusp_resume(void)
 	 */
 	swsusp_free();
 	restore_processor_state();
-	restore_special_mem();
+	restore_highmem();
 	touch_softlockup_watchdog();
 	device_power_up();
 	local_irq_enable();