Merge branch 'linux-2.6'

kernel/power/Kconfig

@@ -78,17 +78,22 @@ config PM_SYSFS_DEPRECATED
 	  are likely to be bus or driver specific.
 
 config SOFTWARE_SUSPEND
-	bool "Software Suspend"
+	bool "Software Suspend (Hibernation)"
 	depends on PM && SWAP && (((X86 || PPC64_SWSUSP) && (!SMP || SUSPEND_SMP)) || ((FRV || PPC32) && !SMP))
 	---help---
-	  Enable the suspend to disk (STD) functionality.
+	  Enable the suspend to disk (STD) functionality, which is usually
+	  called "hibernation" in user interfaces.  STD checkpoints the
+	  system and powers it off; and restores that checkpoint on reboot.
 
 	  You can suspend your machine with 'echo disk > /sys/power/state'.
 	  Alternatively, you can use the additional userland tools available
 	  from <http://suspend.sf.net>.
 
 	  In principle it does not require ACPI or APM, although for example
-	  ACPI will be used if available.
+	  ACPI will be used for the final steps when it is available.  One
+	  of the reasons to use software suspend is that the firmware hooks
+	  for suspend states like suspend-to-RAM (STR) often don't work very
+	  well with Linux.
 
 	  It creates an image which is saved in your active swap. Upon the next
 	  boot, pass the 'resume=/dev/swappartition' argument to the kernel to

kernel/power/disk.c

@@ -130,15 +130,25 @@ int pm_suspend_disk(void)
 {
 	int error;
 
+	/* The snapshot device should not be opened while we're running */
+	if (!atomic_add_unless(&snapshot_device_available, -1, 0))
+		return -EBUSY;
+
+	/* Allocate memory management structures */
+	error = create_basic_memory_bitmaps();
+	if (error)
+		goto Exit;
+
 	error = prepare_processes();
 	if (error)
-		return error;
+		goto Finish;
 
 	if (pm_disk_mode == PM_DISK_TESTPROC) {
 		printk("swsusp debug: Waiting for 5 seconds.\n");
 		mdelay(5000);
 		goto Thaw;
 	}
+
 	/* Free memory before shutting down devices. */
 	error = swsusp_shrink_memory();
 	if (error)
@@ -196,6 +206,10 @@ int pm_suspend_disk(void)
 	resume_console();
  Thaw:
 	unprepare_processes();
+ Finish:
+	free_basic_memory_bitmaps();
+ Exit:
+	atomic_inc(&snapshot_device_available);
 	return error;
 }
 
@@ -239,13 +253,21 @@ static int software_resume(void)
 	}
 
 	pr_debug("PM: Checking swsusp image.\n");
-
 	error = swsusp_check();
 	if (error)
-		goto Done;
+		goto Unlock;
+
+	/* The snapshot device should not be opened while we're running */
+	if (!atomic_add_unless(&snapshot_device_available, -1, 0)) {
+		error = -EBUSY;
+		goto Unlock;
+	}
+
+	error = create_basic_memory_bitmaps();
+	if (error)
+		goto Finish;
 
 	pr_debug("PM: Preparing processes for restore.\n");
-
 	error = prepare_processes();
 	if (error) {
 		swsusp_close();
@@ -280,7 +302,11 @@ static int software_resume(void)
 	printk(KERN_ERR "PM: Restore failed, recovering.\n");
 	unprepare_processes();
  Done:
+	free_basic_memory_bitmaps();
+ Finish:
+	atomic_inc(&snapshot_device_available);
 	/* For success case, the suspend path will release the lock */
+ Unlock:
 	mutex_unlock(&pm_mutex);
 	pr_debug("PM: Resume from disk failed.\n");
 	return 0;
@@ -322,13 +348,40 @@ static const char * const pm_disk_modes[] = {
  *	supports it (as determined from pm_ops->pm_disk_mode).
  */
 
-static ssize_t disk_show(struct subsystem * subsys, char * buf)
+static ssize_t disk_show(struct kset *kset, char *buf)
 {
-	return sprintf(buf, "%s\n", pm_disk_modes[pm_disk_mode]);
+	int i;
+	char *start = buf;
+
+	for (i = PM_DISK_PLATFORM; i < PM_DISK_MAX; i++) {
+		if (!pm_disk_modes[i])
+			continue;
+		switch (i) {
+		case PM_DISK_SHUTDOWN:
+		case PM_DISK_REBOOT:
+		case PM_DISK_TEST:
+		case PM_DISK_TESTPROC:
+			break;
+		default:
+			if (pm_ops && pm_ops->enter &&
+			    (i == pm_ops->pm_disk_mode))
+				break;
+			/* not a valid mode, continue with loop */
+			continue;
+		}
+		if (i == pm_disk_mode)
+			buf += sprintf(buf, "[%s]", pm_disk_modes[i]);
+		else
+			buf += sprintf(buf, "%s", pm_disk_modes[i]);
+		if (i+1 != PM_DISK_MAX)
+			buf += sprintf(buf, " ");
+	}
+	buf += sprintf(buf, "\n");
+	return buf-start;
 }
 
 
-static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n)
+static ssize_t disk_store(struct kset *kset, const char *buf, size_t n)
 {
 	int error = 0;
 	int i;
@@ -373,13 +426,13 @@ static ssize_t disk_store(struct subsystem * s, const char * buf, size_t n)
 
 power_attr(disk);
 
-static ssize_t resume_show(struct subsystem * subsys, char *buf)
+static ssize_t resume_show(struct kset *kset, char *buf)
 {
 	return sprintf(buf,"%d:%d\n", MAJOR(swsusp_resume_device),
 		       MINOR(swsusp_resume_device));
 }
 
-static ssize_t resume_store(struct subsystem *subsys, const char *buf, size_t n)
+static ssize_t resume_store(struct kset *kset, const char *buf, size_t n)
 {
 	unsigned int maj, min;
 	dev_t res;
@@ -405,12 +458,12 @@ static ssize_t resume_store(struct subsystem *subsys, const char *buf, size_t n)
 
 power_attr(resume);
 
-static ssize_t image_size_show(struct subsystem * subsys, char *buf)
+static ssize_t image_size_show(struct kset *kset, char *buf)
 {
 	return sprintf(buf, "%lu\n", image_size);
 }
 
-static ssize_t image_size_store(struct subsystem * subsys, const char * buf, size_t n)
+static ssize_t image_size_store(struct kset *kset, const char *buf, size_t n)
 {
 	unsigned long size;
 
@@ -439,7 +492,7 @@ static struct attribute_group attr_group = {
 
 static int __init pm_disk_init(void)
 {
-	return sysfs_create_group(&power_subsys.kset.kobj,&attr_group);
+	return sysfs_create_group(&power_subsys.kobj, &attr_group);
 }
 
 core_initcall(pm_disk_init);

kernel/power/main.c

@@ -184,17 +184,21 @@ static void suspend_finish(suspend_state_t state)
 static const char * const pm_states[PM_SUSPEND_MAX] = {
 	[PM_SUSPEND_STANDBY]	= "standby",
 	[PM_SUSPEND_MEM]	= "mem",
-#ifdef CONFIG_SOFTWARE_SUSPEND
 	[PM_SUSPEND_DISK]	= "disk",
-#endif
 };
 
 static inline int valid_state(suspend_state_t state)
 {
 	/* Suspend-to-disk does not really need low-level support.
-	 * It can work with reboot if needed. */
+	 * It can work with shutdown/reboot if needed. If it isn't
+	 * configured, then it cannot be supported.
+	 */
 	if (state == PM_SUSPEND_DISK)
+#ifdef CONFIG_SOFTWARE_SUSPEND
 		return 1;
+#else
+		return 0;
+#endif
 
 	/* all other states need lowlevel support and need to be
 	 * valid to the lowlevel implementation, no valid callback
@@ -244,15 +248,6 @@ static int enter_state(suspend_state_t state)
 	return error;
 }
 
-/*
- * This is main interface to the outside world. It needs to be
- * called from process context.
- */
-int software_suspend(void)
-{
-	return enter_state(PM_SUSPEND_DISK);
-}
-
 
 /**
  *	pm_suspend - Externally visible function for suspending system.
@@ -285,7 +280,7 @@ decl_subsys(power,NULL,NULL);
  *	proper enumerated value, and initiates a suspend transition.
  */
 
-static ssize_t state_show(struct subsystem * subsys, char * buf)
+static ssize_t state_show(struct kset *kset, char *buf)
 {
 	int i;
 	char * s = buf;
@@ -298,7 +293,7 @@ static ssize_t state_show(struct subsystem * subsys, char * buf)
 	return (s - buf);
 }
 
-static ssize_t state_store(struct subsystem * subsys, const char * buf, size_t n)
+static ssize_t state_store(struct kset *kset, const char *buf, size_t n)
 {
 	suspend_state_t state = PM_SUSPEND_STANDBY;
 	const char * const *s;
@@ -325,13 +320,13 @@ power_attr(state);
 #ifdef CONFIG_PM_TRACE
 int pm_trace_enabled;
 
-static ssize_t pm_trace_show(struct subsystem * subsys, char * buf)
+static ssize_t pm_trace_show(struct kset *kset, char *buf)
 {
 	return sprintf(buf, "%d\n", pm_trace_enabled);
 }
 
 static ssize_t
-pm_trace_store(struct subsystem * subsys, const char * buf, size_t n)
+pm_trace_store(struct kset *kset, const char *buf, size_t n)
 {
 	int val;
 
@@ -365,7 +360,7 @@ static int __init pm_init(void)
 {
 	int error = subsystem_register(&power_subsys);
 	if (!error)
-		error = sysfs_create_group(&power_subsys.kset.kobj,&attr_group);
+		error = sysfs_create_group(&power_subsys.kobj,&attr_group);
 	return error;
 }
 

kernel/power/power.h

@@ -14,8 +14,18 @@ struct swsusp_info {
 
 
 #ifdef CONFIG_SOFTWARE_SUSPEND
-extern int pm_suspend_disk(void);
+/*
+ * Keep some memory free so that I/O operations can succeed without paging
+ * [Might this be more than 4 MB?]
+ */
+#define PAGES_FOR_IO	((4096 * 1024) >> PAGE_SHIFT)
+/*
+ * Keep 1 MB of memory free so that device drivers can allocate some pages in
+ * their .suspend() routines without breaking the suspend to disk.
+ */
+#define SPARE_PAGES	((1024 * 1024) >> PAGE_SHIFT)
 
+extern int pm_suspend_disk(void);
 #else
 static inline int pm_suspend_disk(void)
 {
@@ -23,6 +33,8 @@ static inline int pm_suspend_disk(void)
 }
 #endif
 
+extern int pfn_is_nosave(unsigned long);
+
 extern struct mutex pm_mutex;
 
 #define power_attr(_name) \
@@ -35,10 +47,7 @@ static struct subsys_attribute _name##_attr = {	\
 	.store	= _name##_store,		\
 }
 
-extern struct subsystem power_subsys;
-
-/* References to section boundaries */
-extern const void __nosave_begin, __nosave_end;
+extern struct kset power_subsys;
 
 /* Preferred image size in bytes (default 500 MB) */
 extern unsigned long image_size;
@@ -49,6 +58,8 @@ extern sector_t swsusp_resume_block;
 extern asmlinkage int swsusp_arch_suspend(void);
 extern asmlinkage int swsusp_arch_resume(void);
 
+extern int create_basic_memory_bitmaps(void);
+extern void free_basic_memory_bitmaps(void);
 extern unsigned int count_data_pages(void);
 
 /**
@@ -139,30 +150,12 @@ struct resume_swap_area {
 #define PMOPS_ENTER	2
 #define PMOPS_FINISH	3
 
-/**
- *	The bitmap is used for tracing allocated swap pages
- *
- *	The entire bitmap consists of a number of bitmap_page
- *	structures linked with the help of the .next member.
- *	Thus each page can be allocated individually, so we only
- *	need to make 0-order memory allocations to create
- *	the bitmap.
- */
+/* If unset, the snapshot device cannot be open. */
+extern atomic_t snapshot_device_available;
 
-#define BITMAP_PAGE_SIZE	(PAGE_SIZE - sizeof(void *))
-#define BITMAP_PAGE_CHUNKS	(BITMAP_PAGE_SIZE / sizeof(long))
-#define BITS_PER_CHUNK		(sizeof(long) * 8)
-#define BITMAP_PAGE_BITS	(BITMAP_PAGE_CHUNKS * BITS_PER_CHUNK)
-
-struct bitmap_page {
-	unsigned long		chunks[BITMAP_PAGE_CHUNKS];
-	struct bitmap_page	*next;
-};
-
-extern void free_bitmap(struct bitmap_page *bitmap);
-extern struct bitmap_page *alloc_bitmap(unsigned int nr_bits);
-extern sector_t alloc_swapdev_block(int swap, struct bitmap_page *bitmap);
-extern void free_all_swap_pages(int swap, struct bitmap_page *bitmap);
+extern sector_t alloc_swapdev_block(int swap);
+extern void free_all_swap_pages(int swap);
+extern int swsusp_swap_in_use(void);
 
 extern int swsusp_check(void);
 extern int swsusp_shrink_memory(void);

kernel/power/process.c

@@ -47,8 +47,10 @@ void refrigerator(void)
 	recalc_sigpending(); /* We sent fake signal, clean it up */
 	spin_unlock_irq(&current->sighand->siglock);
 
-	while (frozen(current)) {
-		current->state = TASK_UNINTERRUPTIBLE;
+	for (;;) {
+		set_current_state(TASK_UNINTERRUPTIBLE);
+		if (!frozen(current))
+			break;
 		schedule();
 	}
 	pr_debug("%s left refrigerator\n", current->comm);

kernel/power/snapshot.c

@@ -21,6 +21,7 @@
 #include <linux/kernel.h>
 #include <linux/pm.h>
 #include <linux/device.h>
+#include <linux/init.h>
 #include <linux/bootmem.h>
 #include <linux/syscalls.h>
 #include <linux/console.h>
@@ -34,6 +35,10 @@
 
 #include "power.h"
 
+static int swsusp_page_is_free(struct page *);
+static void swsusp_set_page_forbidden(struct page *);
+static void swsusp_unset_page_forbidden(struct page *);
+
 /* List of PBEs needed for restoring the pages that were allocated before
  * the suspend and included in the suspend image, but have also been
  * allocated by the "resume" kernel, so their contents cannot be written
@@ -67,15 +72,15 @@ 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 +96,8 @@ 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 +115,9 @@ 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);
 }
@@ -224,11 +229,6 @@ static void chain_free(struct chain_allocator *ca, int clear_page_nosave)
  *	of type unsigned long each).  It also contains the pfns that
  *	correspond to the start and end of the represented memory area and
  *	the number of bit chunks in the block.
- *
- *	NOTE: Memory bitmaps are used for two types of operations only:
- *	"set a bit" and "find the next bit set".  Moreover, the searching
- *	is always carried out after all of the "set a bit" operations
- *	on given bitmap.
  */
 
 #define BM_END_OF_MAP	(~0UL)
@@ -443,15 +443,13 @@ static void memory_bm_free(struct memory_bitmap *bm, int clear_nosave_free)
 }
 
 /**
- *	memory_bm_set_bit - set the bit in the bitmap @bm that corresponds
+ *	memory_bm_find_bit - find the bit in the bitmap @bm that corresponds
  *	to given pfn.  The cur_zone_bm member of @bm and the cur_block member
  *	of @bm->cur_zone_bm are updated.
- *
- *	If the bit cannot be set, the function returns -EINVAL .
  */
 
-static int
-memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
+static void memory_bm_find_bit(struct memory_bitmap *bm, unsigned long pfn,
+				void **addr, unsigned int *bit_nr)
 {
 	struct zone_bitmap *zone_bm;
 	struct bm_block *bb;
@@ -463,8 +461,8 @@ memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
 		/* We don't assume that the zones are sorted by pfns */
 		while (pfn < zone_bm->start_pfn || pfn >= zone_bm->end_pfn) {
 			zone_bm = zone_bm->next;
-			if (unlikely(!zone_bm))
-				return -EINVAL;
+
+			BUG_ON(!zone_bm);
 		}
 		bm->cur.zone_bm = zone_bm;
 	}
@@ -475,13 +473,40 @@ memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
 
 	while (pfn >= bb->end_pfn) {
 		bb = bb->next;
-		if (unlikely(!bb))
-			return -EINVAL;
+
+		BUG_ON(!bb);
 	}
 	zone_bm->cur_block = bb;
 	pfn -= bb->start_pfn;
-	set_bit(pfn % BM_BITS_PER_CHUNK, bb->data + pfn / BM_BITS_PER_CHUNK);
-	return 0;
+	*bit_nr = pfn % BM_BITS_PER_CHUNK;
+	*addr = bb->data + pfn / BM_BITS_PER_CHUNK;
+}
+
+static void memory_bm_set_bit(struct memory_bitmap *bm, unsigned long pfn)
+{
+	void *addr;
+	unsigned int bit;
+
+	memory_bm_find_bit(bm, pfn, &addr, &bit);
+	set_bit(bit, addr);
+}
+
+static void memory_bm_clear_bit(struct memory_bitmap *bm, unsigned long pfn)
+{
+	void *addr;
+	unsigned int bit;
+
+	memory_bm_find_bit(bm, pfn, &addr, &bit);
+	clear_bit(bit, addr);
+}
+
+static int memory_bm_test_bit(struct memory_bitmap *bm, unsigned long pfn)
+{
+	void *addr;
+	unsigned int bit;
+
+	memory_bm_find_bit(bm, pfn, &addr, &bit);
+	return test_bit(bit, addr);
 }
 
 /* Two auxiliary functions for memory_bm_next_pfn */
@@ -563,6 +588,199 @@ static unsigned long memory_bm_next_pfn(struct memory_bitmap *bm)
 	return bb->start_pfn + chunk * BM_BITS_PER_CHUNK + bit;
 }
 
+/**
+ *	This structure represents a range of page frames the contents of which
+ *	should not be saved during the suspend.
+ */
+
+struct nosave_region {
+	struct list_head list;
+	unsigned long start_pfn;
+	unsigned long end_pfn;
+};
+
+static LIST_HEAD(nosave_regions);
+
+/**
+ *	register_nosave_region - register a range of page frames the contents
+ *	of which should not be saved during the suspend (to be used in the early
+ *	initialization code)
+ */
+
+void __init
+register_nosave_region(unsigned long start_pfn, unsigned long end_pfn)
+{
+	struct nosave_region *region;
+
+	if (start_pfn >= end_pfn)
+		return;
+
+	if (!list_empty(&nosave_regions)) {
+		/* Try to extend the previous region (they should be sorted) */
+		region = list_entry(nosave_regions.prev,
+					struct nosave_region, list);
+		if (region->end_pfn == start_pfn) {
+			region->end_pfn = end_pfn;
+			goto Report;
+		}
+	}
+	/* 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);
+ Report:
+	printk("swsusp: Registered nosave memory region: %016lx - %016lx\n",
+		start_pfn << PAGE_SHIFT, end_pfn << PAGE_SHIFT);
+}
+
+/*
+ * Set bits in this map correspond to the page frames the contents of which
+ * should not be saved during the suspend.
+ */
+static struct memory_bitmap *forbidden_pages_map;
+
+/* Set bits in this map correspond to free page frames. */
+static struct memory_bitmap *free_pages_map;
+
+/*
+ * Each page frame allocated for creating the image is marked by setting the
+ * corresponding bits in forbidden_pages_map and free_pages_map simultaneously
+ */
+
+void swsusp_set_page_free(struct page *page)
+{
+	if (free_pages_map)
+		memory_bm_set_bit(free_pages_map, page_to_pfn(page));
+}
+
+static int swsusp_page_is_free(struct page *page)
+{
+	return free_pages_map ?
+		memory_bm_test_bit(free_pages_map, page_to_pfn(page)) : 0;
+}
+
+void swsusp_unset_page_free(struct page *page)
+{
+	if (free_pages_map)
+		memory_bm_clear_bit(free_pages_map, page_to_pfn(page));
+}
+
+static void swsusp_set_page_forbidden(struct page *page)
+{
+	if (forbidden_pages_map)
+		memory_bm_set_bit(forbidden_pages_map, page_to_pfn(page));
+}
+
+int swsusp_page_is_forbidden(struct page *page)
+{
+	return forbidden_pages_map ?
+		memory_bm_test_bit(forbidden_pages_map, page_to_pfn(page)) : 0;
+}
+
+static void swsusp_unset_page_forbidden(struct page *page)
+{
+	if (forbidden_pages_map)
+		memory_bm_clear_bit(forbidden_pages_map, page_to_pfn(page));
+}
+
+/**
+ *	mark_nosave_pages - set bits corresponding to the page frames the
+ *	contents of which should not be saved in a given bitmap.
+ */
+
+static void mark_nosave_pages(struct memory_bitmap *bm)
+{
+	struct nosave_region *region;
+
+	if (list_empty(&nosave_regions))
+		return;
+
+	list_for_each_entry(region, &nosave_regions, list) {
+		unsigned long pfn;
+
+		printk("swsusp: Marking nosave pages: %016lx - %016lx\n",
+				region->start_pfn << PAGE_SHIFT,
+				region->end_pfn << PAGE_SHIFT);
+
+		for (pfn = region->start_pfn; pfn < region->end_pfn; pfn++)
+			memory_bm_set_bit(bm, pfn);
+	}
+}
+
+/**
+ *	create_basic_memory_bitmaps - create bitmaps needed for marking page
+ *	frames that should not be saved and free page frames.  The pointers
+ *	forbidden_pages_map and free_pages_map are only modified if everything
+ *	goes well, because we don't want the bits to be used before both bitmaps
+ *	are set up.
+ */
+
+int create_basic_memory_bitmaps(void)
+{
+	struct memory_bitmap *bm1, *bm2;
+	int error = 0;
+
+	BUG_ON(forbidden_pages_map || free_pages_map);
+
+	bm1 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL);
+	if (!bm1)
+		return -ENOMEM;
+
+	error = memory_bm_create(bm1, GFP_KERNEL, PG_ANY);
+	if (error)
+		goto Free_first_object;
+
+	bm2 = kzalloc(sizeof(struct memory_bitmap), GFP_KERNEL);
+	if (!bm2)
+		goto Free_first_bitmap;
+
+	error = memory_bm_create(bm2, GFP_KERNEL, PG_ANY);
+	if (error)
+		goto Free_second_object;
+
+	forbidden_pages_map = bm1;
+	free_pages_map = bm2;
+	mark_nosave_pages(forbidden_pages_map);
+
+	printk("swsusp: Basic memory bitmaps created\n");
+
+	return 0;
+
+ Free_second_object:
+	kfree(bm2);
+ Free_first_bitmap:
+ 	memory_bm_free(bm1, PG_UNSAFE_CLEAR);
+ Free_first_object:
+	kfree(bm1);
+	return -ENOMEM;
+}
+
+/**
+ *	free_basic_memory_bitmaps - free memory bitmaps allocated by
+ *	create_basic_memory_bitmaps().  The auxiliary pointers are necessary
+ *	so that the bitmaps themselves are not referred to while they are being
+ *	freed.
+ */
+
+void free_basic_memory_bitmaps(void)
+{
+	struct memory_bitmap *bm1, *bm2;
+
+	BUG_ON(!(forbidden_pages_map && free_pages_map));
+
+	bm1 = forbidden_pages_map;
+	bm2 = free_pages_map;
+	forbidden_pages_map = NULL;
+	free_pages_map = NULL;
+	memory_bm_free(bm1, PG_UNSAFE_CLEAR);
+	kfree(bm1);
+	memory_bm_free(bm2, PG_UNSAFE_CLEAR);
+	kfree(bm2);
+
+	printk("swsusp: Basic memory bitmaps freed\n");
+}
+
 /**
  *	snapshot_additional_pages - estimate the number of additional pages
  *	be needed for setting up the suspend image data structures for given
@@ -615,7 +833,8 @@ 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;
@@ -650,17 +869,6 @@ static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; }
 static inline unsigned int count_highmem_pages(void) { return 0; }
 #endif /* CONFIG_HIGHMEM */
 
-/**
- *	pfn_is_nosave - check if given pfn is in the 'nosave' section
- */
-
-static inline int pfn_is_nosave(unsigned long pfn)
-{
-	unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
-	unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT;
-	return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
-}
-
 /**
  *	saveable - Determine whether a non-highmem page should be included in
  *	the suspend image.
@@ -681,7 +889,7 @@ 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))
@@ -821,9 +1029,10 @@ 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);
 				}
 			}
@@ -1146,7 +1355,7 @@ 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" */
@@ -1155,7 +1364,7 @@ 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;
 		}
@@ -1321,14 +1530,14 @@ 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;
@@ -1360,7 +1569,7 @@ 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.
 		 */
@@ -1522,14 +1731,14 @@ 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 */
@@ -1558,7 +1767,7 @@ 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.
 		 */

kernel/power/swap.c

@@ -33,12 +33,14 @@ extern char resume_file[];
 
 #define SWSUSP_SIG	"S1SUSPEND"
 
-static struct swsusp_header {
+struct swsusp_header {
 	char reserved[PAGE_SIZE - 20 - sizeof(sector_t)];
 	sector_t image;
 	char	orig_sig[10];
 	char	sig[10];
-} __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header;
+} __attribute__((packed));
+
+static struct swsusp_header *swsusp_header;
 
 /*
  * General things
@@ -141,14 +143,14 @@ static int mark_swapfiles(sector_t start)
 {
 	int error;
 
-	bio_read_page(swsusp_resume_block, &swsusp_header, NULL);
-	if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) ||
-	    !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) {
-		memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10);
-		memcpy(swsusp_header.sig,SWSUSP_SIG, 10);
-		swsusp_header.image = start;
+	bio_read_page(swsusp_resume_block, swsusp_header, NULL);
+	if (!memcmp("SWAP-SPACE",swsusp_header->sig, 10) ||
+	    !memcmp("SWAPSPACE2",swsusp_header->sig, 10)) {
+		memcpy(swsusp_header->orig_sig,swsusp_header->sig, 10);
+		memcpy(swsusp_header->sig,SWSUSP_SIG, 10);
+		swsusp_header->image = start;
 		error = bio_write_page(swsusp_resume_block,
-					&swsusp_header, NULL);
+					swsusp_header, NULL);
 	} else {
 		printk(KERN_ERR "swsusp: Swap header not found!\n");
 		error = -ENODEV;
@@ -241,7 +243,6 @@ struct swap_map_page {
 struct swap_map_handle {
 	struct swap_map_page *cur;
 	sector_t cur_swap;
-	struct bitmap_page *bitmap;
 	unsigned int k;
 };
 
@@ -250,9 +251,6 @@ static void release_swap_writer(struct swap_map_handle *handle)
 	if (handle->cur)
 		free_page((unsigned long)handle->cur);
 	handle->cur = NULL;
-	if (handle->bitmap)
-		free_bitmap(handle->bitmap);
-	handle->bitmap = NULL;
 }
 
 static int get_swap_writer(struct swap_map_handle *handle)
@@ -260,12 +258,7 @@ static int get_swap_writer(struct swap_map_handle *handle)
 	handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL);
 	if (!handle->cur)
 		return -ENOMEM;
-	handle->bitmap = alloc_bitmap(count_swap_pages(root_swap, 0));
-	if (!handle->bitmap) {
-		release_swap_writer(handle);
-		return -ENOMEM;
-	}
-	handle->cur_swap = alloc_swapdev_block(root_swap, handle->bitmap);
+	handle->cur_swap = alloc_swapdev_block(root_swap);
 	if (!handle->cur_swap) {
 		release_swap_writer(handle);
 		return -ENOSPC;
@@ -282,7 +275,7 @@ static int swap_write_page(struct swap_map_handle *handle, void *buf,
 
 	if (!handle->cur)
 		return -EINVAL;
-	offset = alloc_swapdev_block(root_swap, handle->bitmap);
+	offset = alloc_swapdev_block(root_swap);
 	error = write_page(buf, offset, bio_chain);
 	if (error)
 		return error;
@@ -291,7 +284,7 @@ static int swap_write_page(struct swap_map_handle *handle, void *buf,
 		error = wait_on_bio_chain(bio_chain);
 		if (error)
 			goto out;
-		offset = alloc_swapdev_block(root_swap, handle->bitmap);
+		offset = alloc_swapdev_block(root_swap);
 		if (!offset)
 			return -ENOSPC;
 		handle->cur->next_swap = offset;
@@ -428,7 +421,8 @@ int swsusp_write(void)
 		}
 	}
 	if (error)
-		free_all_swap_pages(root_swap, handle.bitmap);
+		free_all_swap_pages(root_swap);
+
 	release_swap_writer(&handle);
  out:
 	swsusp_close();
@@ -564,7 +558,7 @@ int swsusp_read(void)
 	if (error < PAGE_SIZE)
 		return error < 0 ? error : -EFAULT;
 	header = (struct swsusp_info *)data_of(snapshot);
-	error = get_swap_reader(&handle, swsusp_header.image);
+	error = get_swap_reader(&handle, swsusp_header->image);
 	if (!error)
 		error = swap_read_page(&handle, header, NULL);
 	if (!error)
@@ -591,17 +585,17 @@ int swsusp_check(void)
 	resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
 	if (!IS_ERR(resume_bdev)) {
 		set_blocksize(resume_bdev, PAGE_SIZE);
-		memset(&swsusp_header, 0, sizeof(swsusp_header));
+		memset(swsusp_header, 0, sizeof(PAGE_SIZE));
 		error = bio_read_page(swsusp_resume_block,
-					&swsusp_header, NULL);
+					swsusp_header, NULL);
 		if (error)
 			return error;
 
-		if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) {
-			memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10);
+		if (!memcmp(SWSUSP_SIG, swsusp_header->sig, 10)) {
+			memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10);
 			/* Reset swap signature now */
 			error = bio_write_page(swsusp_resume_block,
-						&swsusp_header, NULL);
+						swsusp_header, NULL);
 		} else {
 			return -EINVAL;
 		}
@@ -632,3 +626,13 @@ void swsusp_close(void)
 
 	blkdev_put(resume_bdev);
 }
+
+static int swsusp_header_init(void)
+{
+	swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL);
+	if (!swsusp_header)
+		panic("Could not allocate memory for swsusp_header\n");
+	return 0;
+}
+
+core_initcall(swsusp_header_init);

kernel/power/swsusp.c

@@ -50,6 +50,7 @@
 #include <linux/syscalls.h>
 #include <linux/highmem.h>
 #include <linux/time.h>
+#include <linux/rbtree.h>
 
 #include "power.h"
 
@@ -74,72 +75,69 @@ static inline unsigned int count_highmem_pages(void) { return 0; }
 /**
  *	The following functions are used for tracing the allocated
  *	swap pages, so that they can be freed in case of an error.
- *
- *	The functions operate on a linked bitmap structure defined
- *	in power.h
  */
 
-void free_bitmap(struct bitmap_page *bitmap)
+struct swsusp_extent {
+	struct rb_node node;
+	unsigned long start;
+	unsigned long end;
+};
+
+static struct rb_root swsusp_extents = RB_ROOT;
+
+static int swsusp_extents_insert(unsigned long swap_offset)
 {
-	struct bitmap_page *bp;
+	struct rb_node **new = &(swsusp_extents.rb_node);
+	struct rb_node *parent = NULL;
+	struct swsusp_extent *ext;
 
-	while (bitmap) {
-		bp = bitmap->next;
-		free_page((unsigned long)bitmap);
-		bitmap = bp;
-	}
-}
-
-struct bitmap_page *alloc_bitmap(unsigned int nr_bits)
-{
-	struct bitmap_page *bitmap, *bp;
-	unsigned int n;
-
-	if (!nr_bits)
-		return NULL;
-
-	bitmap = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL);
-	bp = bitmap;
-	for (n = BITMAP_PAGE_BITS; n < nr_bits; n += BITMAP_PAGE_BITS) {
-		bp->next = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL);
-		bp = bp->next;
-		if (!bp) {
-			free_bitmap(bitmap);
-			return NULL;
+	/* Figure out where to put the new node */
+	while (*new) {
+		ext = container_of(*new, struct swsusp_extent, node);
+		parent = *new;
+		if (swap_offset < ext->start) {
+			/* Try to merge */
+			if (swap_offset == ext->start - 1) {
+				ext->start--;
+				return 0;
+			}
+			new = &((*new)->rb_left);
+		} else if (swap_offset > ext->end) {
+			/* Try to merge */
+			if (swap_offset == ext->end + 1) {
+				ext->end++;
+				return 0;
+			}
+			new = &((*new)->rb_right);
+		} else {
+			/* It already is in the tree */
+			return -EINVAL;
 		}
 	}
-	return bitmap;
-}
+	/* Add the new node and rebalance the tree. */
+	ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL);
+	if (!ext)
+		return -ENOMEM;
 
-static int bitmap_set(struct bitmap_page *bitmap, unsigned long bit)
-{
-	unsigned int n;
-
-	n = BITMAP_PAGE_BITS;
-	while (bitmap && n <= bit) {
-		n += BITMAP_PAGE_BITS;
-		bitmap = bitmap->next;
-	}
-	if (!bitmap)
-		return -EINVAL;
-	n -= BITMAP_PAGE_BITS;
-	bit -= n;
-	n = 0;
-	while (bit >= BITS_PER_CHUNK) {
-		bit -= BITS_PER_CHUNK;
-		n++;
-	}
-	bitmap->chunks[n] |= (1UL << bit);
+	ext->start = swap_offset;
+	ext->end = swap_offset;
+	rb_link_node(&ext->node, parent, new);
+	rb_insert_color(&ext->node, &swsusp_extents);
 	return 0;
 }
 
-sector_t alloc_swapdev_block(int swap, struct bitmap_page *bitmap)
+/**
+ *	alloc_swapdev_block - allocate a swap page and register that it has
+ *	been allocated, so that it can be freed in case of an error.
+ */
+
+sector_t alloc_swapdev_block(int swap)
 {
 	unsigned long offset;
 
 	offset = swp_offset(get_swap_page_of_type(swap));
 	if (offset) {
-		if (bitmap_set(bitmap, offset))
+		if (swsusp_extents_insert(offset))
 			swap_free(swp_entry(swap, offset));
 		else
 			return swapdev_block(swap, offset);
@@ -147,23 +145,34 @@ sector_t alloc_swapdev_block(int swap, struct bitmap_page *bitmap)
 	return 0;
 }
 
-void free_all_swap_pages(int swap, struct bitmap_page *bitmap)
-{
-	unsigned int bit, n;
-	unsigned long test;
+/**
+ *	free_all_swap_pages - free swap pages allocated for saving image data.
+ *	It also frees the extents used to register which swap entres had been
+ *	allocated.
+ */
 
-	bit = 0;
-	while (bitmap) {
-		for (n = 0; n < BITMAP_PAGE_CHUNKS; n++)
-			for (test = 1UL; test; test <<= 1) {
-				if (bitmap->chunks[n] & test)
-					swap_free(swp_entry(swap, bit));
-				bit++;
-			}
-		bitmap = bitmap->next;
+void free_all_swap_pages(int swap)
+{
+	struct rb_node *node;
+
+	while ((node = swsusp_extents.rb_node)) {
+		struct swsusp_extent *ext;
+		unsigned long offset;
+
+		ext = container_of(node, struct swsusp_extent, node);
+		rb_erase(node, &swsusp_extents);
+		for (offset = ext->start; offset <= ext->end; offset++)
+			swap_free(swp_entry(swap, offset));
+
+		kfree(ext);
 	}
 }
 
+int swsusp_swap_in_use(void)
+{
+	return (swsusp_extents.rb_node != NULL);
+}
+
 /**
  *	swsusp_show_speed - print the time elapsed between two events represented by
  *	@start and @stop
@@ -224,7 +233,7 @@ int swsusp_shrink_memory(void)
 		long size, highmem_size;
 
 		highmem_size = count_highmem_pages();
-		size = count_data_pages() + PAGES_FOR_IO;
+		size = count_data_pages() + PAGES_FOR_IO + SPARE_PAGES;
 		tmp = size;
 		size += highmem_size;
 		for_each_zone (zone)

kernel/power/user.c

@@ -33,25 +33,29 @@
 static struct snapshot_data {
 	struct snapshot_handle handle;
 	int swap;
-	struct bitmap_page *bitmap;
 	int mode;
 	char frozen;
 	char ready;
 	char platform_suspend;
 } snapshot_state;
 
-static atomic_t device_available = ATOMIC_INIT(1);
+atomic_t snapshot_device_available = ATOMIC_INIT(1);
 
 static int snapshot_open(struct inode *inode, struct file *filp)
 {
 	struct snapshot_data *data;
 
-	if (!atomic_add_unless(&device_available, -1, 0))
+	if (!atomic_add_unless(&snapshot_device_available, -1, 0))
 		return -EBUSY;
 
-	if ((filp->f_flags & O_ACCMODE) == O_RDWR)
+	if ((filp->f_flags & O_ACCMODE) == O_RDWR) {
+		atomic_inc(&snapshot_device_available);
 		return -ENOSYS;
-
+	}
+	if(create_basic_memory_bitmaps()) {
+		atomic_inc(&snapshot_device_available);
+		return -ENOMEM;
+	}
 	nonseekable_open(inode, filp);
 	data = &snapshot_state;
 	filp->private_data = data;
@@ -64,7 +68,6 @@ static int snapshot_open(struct inode *inode, struct file *filp)
 		data->swap = -1;
 		data->mode = O_WRONLY;
 	}
-	data->bitmap = NULL;
 	data->frozen = 0;
 	data->ready = 0;
 	data->platform_suspend = 0;
@@ -77,16 +80,15 @@ static int snapshot_release(struct inode *inode, struct file *filp)
 	struct snapshot_data *data;
 
 	swsusp_free();
+	free_basic_memory_bitmaps();
 	data = filp->private_data;
-	free_all_swap_pages(data->swap, data->bitmap);
-	free_bitmap(data->bitmap);
+	free_all_swap_pages(data->swap);
 	if (data->frozen) {
 		mutex_lock(&pm_mutex);
 		thaw_processes();
-		enable_nonboot_cpus();
 		mutex_unlock(&pm_mutex);
 	}
-	atomic_inc(&device_available);
+	atomic_inc(&snapshot_device_available);
 	return 0;
 }
 
@@ -294,14 +296,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
 			error = -ENODEV;
 			break;
 		}
-		if (!data->bitmap) {
-			data->bitmap = alloc_bitmap(count_swap_pages(data->swap, 0));
-			if (!data->bitmap) {
-				error = -ENOMEM;
-				break;
-			}
-		}
-		offset = alloc_swapdev_block(data->swap, data->bitmap);
+		offset = alloc_swapdev_block(data->swap);
 		if (offset) {
 			offset <<= PAGE_SHIFT;
 			error = put_user(offset, (sector_t __user *)arg);
@@ -315,13 +310,11 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
 			error = -ENODEV;
 			break;
 		}
-		free_all_swap_pages(data->swap, data->bitmap);
-		free_bitmap(data->bitmap);
-		data->bitmap = NULL;
+		free_all_swap_pages(data->swap);
 		break;
 
 	case SNAPSHOT_SET_SWAP_FILE:
-		if (!data->bitmap) {
+		if (!swsusp_swap_in_use()) {
 			/*
 			 * User space encodes device types as two-byte values,
 			 * so we need to recode them
@@ -420,7 +413,7 @@ static int snapshot_ioctl(struct inode *inode, struct file *filp,
 		break;
 
 	case SNAPSHOT_SET_SWAP_AREA:
-		if (data->bitmap) {
+		if (swsusp_swap_in_use()) {
 			error = -EPERM;
 		} else {
 			struct resume_swap_area swap_area;