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1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_SUSPEND_H
3 #define _LINUX_SUSPEND_H
4 
5 #include <linux/swap.h>
6 #include <linux/notifier.h>
7 #include <linux/init.h>
8 #include <linux/pm.h>
9 #include <linux/mm.h>
10 #include <linux/freezer.h>
11 #include <asm/errno.h>
12 
13 #ifdef CONFIG_VT
14 extern void pm_set_vt_switch(int);
15 #else
pm_set_vt_switch(int do_switch)16 static inline void pm_set_vt_switch(int do_switch)
17 {
18 }
19 #endif
20 
21 #ifdef CONFIG_VT_CONSOLE_SLEEP
22 extern void pm_prepare_console(void);
23 extern void pm_restore_console(void);
24 #else
pm_prepare_console(void)25 static inline void pm_prepare_console(void)
26 {
27 }
28 
pm_restore_console(void)29 static inline void pm_restore_console(void)
30 {
31 }
32 #endif
33 
34 typedef int __bitwise suspend_state_t;
35 
36 #define PM_SUSPEND_ON		((__force suspend_state_t) 0)
37 #define PM_SUSPEND_TO_IDLE	((__force suspend_state_t) 1)
38 #define PM_SUSPEND_STANDBY	((__force suspend_state_t) 2)
39 #define PM_SUSPEND_MEM		((__force suspend_state_t) 3)
40 #define PM_SUSPEND_MIN		PM_SUSPEND_TO_IDLE
41 #define PM_SUSPEND_MAX		((__force suspend_state_t) 4)
42 
43 enum suspend_stat_step {
44 	SUSPEND_FREEZE = 1,
45 	SUSPEND_PREPARE,
46 	SUSPEND_SUSPEND,
47 	SUSPEND_SUSPEND_LATE,
48 	SUSPEND_SUSPEND_NOIRQ,
49 	SUSPEND_RESUME_NOIRQ,
50 	SUSPEND_RESUME_EARLY,
51 	SUSPEND_RESUME
52 };
53 
54 struct suspend_stats {
55 	int	success;
56 	int	fail;
57 	int	failed_freeze;
58 	int	failed_prepare;
59 	int	failed_suspend;
60 	int	failed_suspend_late;
61 	int	failed_suspend_noirq;
62 	int	failed_resume;
63 	int	failed_resume_early;
64 	int	failed_resume_noirq;
65 #define	REC_FAILED_NUM	2
66 	int	last_failed_dev;
67 	char	failed_devs[REC_FAILED_NUM][40];
68 	int	last_failed_errno;
69 	int	errno[REC_FAILED_NUM];
70 	int	last_failed_step;
71 	enum suspend_stat_step	failed_steps[REC_FAILED_NUM];
72 };
73 
74 extern struct suspend_stats suspend_stats;
75 
dpm_save_failed_dev(const char * name)76 static inline void dpm_save_failed_dev(const char *name)
77 {
78 	strlcpy(suspend_stats.failed_devs[suspend_stats.last_failed_dev],
79 		name,
80 		sizeof(suspend_stats.failed_devs[0]));
81 	suspend_stats.last_failed_dev++;
82 	suspend_stats.last_failed_dev %= REC_FAILED_NUM;
83 }
84 
dpm_save_failed_errno(int err)85 static inline void dpm_save_failed_errno(int err)
86 {
87 	suspend_stats.errno[suspend_stats.last_failed_errno] = err;
88 	suspend_stats.last_failed_errno++;
89 	suspend_stats.last_failed_errno %= REC_FAILED_NUM;
90 }
91 
dpm_save_failed_step(enum suspend_stat_step step)92 static inline void dpm_save_failed_step(enum suspend_stat_step step)
93 {
94 	suspend_stats.failed_steps[suspend_stats.last_failed_step] = step;
95 	suspend_stats.last_failed_step++;
96 	suspend_stats.last_failed_step %= REC_FAILED_NUM;
97 }
98 
99 /**
100  * struct platform_suspend_ops - Callbacks for managing platform dependent
101  *	system sleep states.
102  *
103  * @valid: Callback to determine if given system sleep state is supported by
104  *	the platform.
105  *	Valid (ie. supported) states are advertised in /sys/power/state.  Note
106  *	that it still may be impossible to enter given system sleep state if the
107  *	conditions aren't right.
108  *	There is the %suspend_valid_only_mem function available that can be
109  *	assigned to this if the platform only supports mem sleep.
110  *
111  * @begin: Initialise a transition to given system sleep state.
112  *	@begin() is executed right prior to suspending devices.  The information
113  *	conveyed to the platform code by @begin() should be disregarded by it as
114  *	soon as @end() is executed.  If @begin() fails (ie. returns nonzero),
115  *	@prepare(), @enter() and @finish() will not be called by the PM core.
116  *	This callback is optional.  However, if it is implemented, the argument
117  *	passed to @enter() is redundant and should be ignored.
118  *
119  * @prepare: Prepare the platform for entering the system sleep state indicated
120  *	by @begin().
121  *	@prepare() is called right after devices have been suspended (ie. the
122  *	appropriate .suspend() method has been executed for each device) and
123  *	before device drivers' late suspend callbacks are executed.  It returns
124  *	0 on success or a negative error code otherwise, in which case the
125  *	system cannot enter the desired sleep state (@prepare_late(), @enter(),
126  *	and @wake() will not be called in that case).
127  *
128  * @prepare_late: Finish preparing the platform for entering the system sleep
129  *	state indicated by @begin().
130  *	@prepare_late is called before disabling nonboot CPUs and after
131  *	device drivers' late suspend callbacks have been executed.  It returns
132  *	0 on success or a negative error code otherwise, in which case the
133  *	system cannot enter the desired sleep state (@enter() will not be
134  *	executed).
135  *
136  * @enter: Enter the system sleep state indicated by @begin() or represented by
137  *	the argument if @begin() is not implemented.
138  *	This callback is mandatory.  It returns 0 on success or a negative
139  *	error code otherwise, in which case the system cannot enter the desired
140  *	sleep state.
141  *
142  * @wake: Called when the system has just left a sleep state, right after
143  *	the nonboot CPUs have been enabled and before device drivers' early
144  *	resume callbacks are executed.
145  *	This callback is optional, but should be implemented by the platforms
146  *	that implement @prepare_late().  If implemented, it is always called
147  *	after @prepare_late and @enter(), even if one of them fails.
148  *
149  * @finish: Finish wake-up of the platform.
150  *	@finish is called right prior to calling device drivers' regular suspend
151  *	callbacks.
152  *	This callback is optional, but should be implemented by the platforms
153  *	that implement @prepare().  If implemented, it is always called after
154  *	@enter() and @wake(), even if any of them fails.  It is executed after
155  *	a failing @prepare.
156  *
157  * @suspend_again: Returns whether the system should suspend again (true) or
158  *	not (false). If the platform wants to poll sensors or execute some
159  *	code during suspended without invoking userspace and most of devices,
160  *	suspend_again callback is the place assuming that periodic-wakeup or
161  *	alarm-wakeup is already setup. This allows to execute some codes while
162  *	being kept suspended in the view of userland and devices.
163  *
164  * @end: Called by the PM core right after resuming devices, to indicate to
165  *	the platform that the system has returned to the working state or
166  *	the transition to the sleep state has been aborted.
167  *	This callback is optional, but should be implemented by the platforms
168  *	that implement @begin().  Accordingly, platforms implementing @begin()
169  *	should also provide a @end() which cleans up transitions aborted before
170  *	@enter().
171  *
172  * @recover: Recover the platform from a suspend failure.
173  *	Called by the PM core if the suspending of devices fails.
174  *	This callback is optional and should only be implemented by platforms
175  *	which require special recovery actions in that situation.
176  */
177 struct platform_suspend_ops {
178 	int (*valid)(suspend_state_t state);
179 	int (*begin)(suspend_state_t state);
180 	int (*prepare)(void);
181 	int (*prepare_late)(void);
182 	int (*enter)(suspend_state_t state);
183 	void (*wake)(void);
184 	void (*finish)(void);
185 	bool (*suspend_again)(void);
186 	void (*end)(void);
187 	void (*recover)(void);
188 };
189 
190 struct platform_s2idle_ops {
191 	int (*begin)(void);
192 	int (*prepare)(void);
193 	void (*wake)(void);
194 	void (*sync)(void);
195 	void (*restore)(void);
196 	void (*end)(void);
197 };
198 
199 #ifdef CONFIG_SUSPEND
200 extern suspend_state_t mem_sleep_current;
201 extern suspend_state_t mem_sleep_default;
202 
203 /**
204  * suspend_set_ops - set platform dependent suspend operations
205  * @ops: The new suspend operations to set.
206  */
207 extern void suspend_set_ops(const struct platform_suspend_ops *ops);
208 extern int suspend_valid_only_mem(suspend_state_t state);
209 
210 extern unsigned int pm_suspend_global_flags;
211 
212 #define PM_SUSPEND_FLAG_FW_SUSPEND	(1 << 0)
213 #define PM_SUSPEND_FLAG_FW_RESUME	(1 << 1)
214 
pm_suspend_clear_flags(void)215 static inline void pm_suspend_clear_flags(void)
216 {
217 	pm_suspend_global_flags = 0;
218 }
219 
pm_set_suspend_via_firmware(void)220 static inline void pm_set_suspend_via_firmware(void)
221 {
222 	pm_suspend_global_flags |= PM_SUSPEND_FLAG_FW_SUSPEND;
223 }
224 
pm_set_resume_via_firmware(void)225 static inline void pm_set_resume_via_firmware(void)
226 {
227 	pm_suspend_global_flags |= PM_SUSPEND_FLAG_FW_RESUME;
228 }
229 
pm_suspend_via_firmware(void)230 static inline bool pm_suspend_via_firmware(void)
231 {
232 	return !!(pm_suspend_global_flags & PM_SUSPEND_FLAG_FW_SUSPEND);
233 }
234 
pm_resume_via_firmware(void)235 static inline bool pm_resume_via_firmware(void)
236 {
237 	return !!(pm_suspend_global_flags & PM_SUSPEND_FLAG_FW_RESUME);
238 }
239 
240 /* Suspend-to-idle state machnine. */
241 enum s2idle_states {
242 	S2IDLE_STATE_NONE,      /* Not suspended/suspending. */
243 	S2IDLE_STATE_ENTER,     /* Enter suspend-to-idle. */
244 	S2IDLE_STATE_WAKE,      /* Wake up from suspend-to-idle. */
245 };
246 
247 extern enum s2idle_states __read_mostly s2idle_state;
248 
idle_should_enter_s2idle(void)249 static inline bool idle_should_enter_s2idle(void)
250 {
251 	return unlikely(s2idle_state == S2IDLE_STATE_ENTER);
252 }
253 
254 extern void __init pm_states_init(void);
255 extern void s2idle_set_ops(const struct platform_s2idle_ops *ops);
256 extern void s2idle_wake(void);
257 
258 /**
259  * arch_suspend_disable_irqs - disable IRQs for suspend
260  *
261  * Disables IRQs (in the default case). This is a weak symbol in the common
262  * code and thus allows architectures to override it if more needs to be
263  * done. Not called for suspend to disk.
264  */
265 extern void arch_suspend_disable_irqs(void);
266 
267 /**
268  * arch_suspend_enable_irqs - enable IRQs after suspend
269  *
270  * Enables IRQs (in the default case). This is a weak symbol in the common
271  * code and thus allows architectures to override it if more needs to be
272  * done. Not called for suspend to disk.
273  */
274 extern void arch_suspend_enable_irqs(void);
275 
276 extern int pm_suspend(suspend_state_t state);
277 #else /* !CONFIG_SUSPEND */
278 #define suspend_valid_only_mem	NULL
279 
pm_suspend_clear_flags(void)280 static inline void pm_suspend_clear_flags(void) {}
pm_set_suspend_via_firmware(void)281 static inline void pm_set_suspend_via_firmware(void) {}
pm_set_resume_via_firmware(void)282 static inline void pm_set_resume_via_firmware(void) {}
pm_suspend_via_firmware(void)283 static inline bool pm_suspend_via_firmware(void) { return false; }
pm_resume_via_firmware(void)284 static inline bool pm_resume_via_firmware(void) { return false; }
285 
suspend_set_ops(const struct platform_suspend_ops * ops)286 static inline void suspend_set_ops(const struct platform_suspend_ops *ops) {}
pm_suspend(suspend_state_t state)287 static inline int pm_suspend(suspend_state_t state) { return -ENOSYS; }
idle_should_enter_s2idle(void)288 static inline bool idle_should_enter_s2idle(void) { return false; }
pm_states_init(void)289 static inline void __init pm_states_init(void) {}
s2idle_set_ops(const struct platform_s2idle_ops * ops)290 static inline void s2idle_set_ops(const struct platform_s2idle_ops *ops) {}
s2idle_wake(void)291 static inline void s2idle_wake(void) {}
292 #endif /* !CONFIG_SUSPEND */
293 
294 /* struct pbe is used for creating lists of pages that should be restored
295  * atomically during the resume from disk, because the page frames they have
296  * occupied before the suspend are in use.
297  */
298 struct pbe {
299 	void *address;		/* address of the copy */
300 	void *orig_address;	/* original address of a page */
301 	struct pbe *next;
302 };
303 
304 /* mm/page_alloc.c */
305 extern void mark_free_pages(struct zone *zone);
306 
307 /**
308  * struct platform_hibernation_ops - hibernation platform support
309  *
310  * The methods in this structure allow a platform to carry out special
311  * operations required by it during a hibernation transition.
312  *
313  * All the methods below, except for @recover(), must be implemented.
314  *
315  * @begin: Tell the platform driver that we're starting hibernation.
316  *	Called right after shrinking memory and before freezing devices.
317  *
318  * @end: Called by the PM core right after resuming devices, to indicate to
319  *	the platform that the system has returned to the working state.
320  *
321  * @pre_snapshot: Prepare the platform for creating the hibernation image.
322  *	Called right after devices have been frozen and before the nonboot
323  *	CPUs are disabled (runs with IRQs on).
324  *
325  * @finish: Restore the previous state of the platform after the hibernation
326  *	image has been created *or* put the platform into the normal operation
327  *	mode after the hibernation (the same method is executed in both cases).
328  *	Called right after the nonboot CPUs have been enabled and before
329  *	thawing devices (runs with IRQs on).
330  *
331  * @prepare: Prepare the platform for entering the low power state.
332  *	Called right after the hibernation image has been saved and before
333  *	devices are prepared for entering the low power state.
334  *
335  * @enter: Put the system into the low power state after the hibernation image
336  *	has been saved to disk.
337  *	Called after the nonboot CPUs have been disabled and all of the low
338  *	level devices have been shut down (runs with IRQs off).
339  *
340  * @leave: Perform the first stage of the cleanup after the system sleep state
341  *	indicated by @set_target() has been left.
342  *	Called right after the control has been passed from the boot kernel to
343  *	the image kernel, before the nonboot CPUs are enabled and before devices
344  *	are resumed.  Executed with interrupts disabled.
345  *
346  * @pre_restore: Prepare system for the restoration from a hibernation image.
347  *	Called right after devices have been frozen and before the nonboot
348  *	CPUs are disabled (runs with IRQs on).
349  *
350  * @restore_cleanup: Clean up after a failing image restoration.
351  *	Called right after the nonboot CPUs have been enabled and before
352  *	thawing devices (runs with IRQs on).
353  *
354  * @recover: Recover the platform from a failure to suspend devices.
355  *	Called by the PM core if the suspending of devices during hibernation
356  *	fails.  This callback is optional and should only be implemented by
357  *	platforms which require special recovery actions in that situation.
358  */
359 struct platform_hibernation_ops {
360 	int (*begin)(void);
361 	void (*end)(void);
362 	int (*pre_snapshot)(void);
363 	void (*finish)(void);
364 	int (*prepare)(void);
365 	int (*enter)(void);
366 	void (*leave)(void);
367 	int (*pre_restore)(void);
368 	void (*restore_cleanup)(void);
369 	void (*recover)(void);
370 };
371 
372 #ifdef CONFIG_HIBERNATION
373 /* kernel/power/snapshot.c */
374 extern void __register_nosave_region(unsigned long b, unsigned long e, int km);
register_nosave_region(unsigned long b,unsigned long e)375 static inline void __init register_nosave_region(unsigned long b, unsigned long e)
376 {
377 	__register_nosave_region(b, e, 0);
378 }
register_nosave_region_late(unsigned long b,unsigned long e)379 static inline void __init register_nosave_region_late(unsigned long b, unsigned long e)
380 {
381 	__register_nosave_region(b, e, 1);
382 }
383 extern int swsusp_page_is_forbidden(struct page *);
384 extern void swsusp_set_page_free(struct page *);
385 extern void swsusp_unset_page_free(struct page *);
386 extern unsigned long get_safe_page(gfp_t gfp_mask);
387 extern asmlinkage int swsusp_arch_suspend(void);
388 extern asmlinkage int swsusp_arch_resume(void);
389 
390 extern void hibernation_set_ops(const struct platform_hibernation_ops *ops);
391 extern int hibernate(void);
392 extern bool system_entering_hibernation(void);
393 extern bool hibernation_available(void);
394 asmlinkage int swsusp_save(void);
395 extern struct pbe *restore_pblist;
396 #else /* CONFIG_HIBERNATION */
register_nosave_region(unsigned long b,unsigned long e)397 static inline void register_nosave_region(unsigned long b, unsigned long e) {}
register_nosave_region_late(unsigned long b,unsigned long e)398 static inline void register_nosave_region_late(unsigned long b, unsigned long e) {}
swsusp_page_is_forbidden(struct page * p)399 static inline int swsusp_page_is_forbidden(struct page *p) { return 0; }
swsusp_set_page_free(struct page * p)400 static inline void swsusp_set_page_free(struct page *p) {}
swsusp_unset_page_free(struct page * p)401 static inline void swsusp_unset_page_free(struct page *p) {}
402 
hibernation_set_ops(const struct platform_hibernation_ops * ops)403 static inline void hibernation_set_ops(const struct platform_hibernation_ops *ops) {}
hibernate(void)404 static inline int hibernate(void) { return -ENOSYS; }
system_entering_hibernation(void)405 static inline bool system_entering_hibernation(void) { return false; }
hibernation_available(void)406 static inline bool hibernation_available(void) { return false; }
407 #endif /* CONFIG_HIBERNATION */
408 
409 /* Hibernation and suspend events */
410 #define PM_HIBERNATION_PREPARE	0x0001 /* Going to hibernate */
411 #define PM_POST_HIBERNATION	0x0002 /* Hibernation finished */
412 #define PM_SUSPEND_PREPARE	0x0003 /* Going to suspend the system */
413 #define PM_POST_SUSPEND		0x0004 /* Suspend finished */
414 #define PM_RESTORE_PREPARE	0x0005 /* Going to restore a saved image */
415 #define PM_POST_RESTORE		0x0006 /* Restore failed */
416 
417 extern struct mutex pm_mutex;
418 
419 #ifdef CONFIG_PM_SLEEP
420 void save_processor_state(void);
421 void restore_processor_state(void);
422 
423 /* kernel/power/main.c */
424 extern int register_pm_notifier(struct notifier_block *nb);
425 extern int unregister_pm_notifier(struct notifier_block *nb);
426 
427 #define pm_notifier(fn, pri) {				\
428 	static struct notifier_block fn##_nb =			\
429 		{ .notifier_call = fn, .priority = pri };	\
430 	register_pm_notifier(&fn##_nb);			\
431 }
432 
433 /* drivers/base/power/wakeup.c */
434 extern bool events_check_enabled;
435 extern unsigned int pm_wakeup_irq;
436 extern suspend_state_t pm_suspend_target_state;
437 
438 extern bool pm_wakeup_pending(void);
439 extern void pm_system_wakeup(void);
440 extern void pm_system_cancel_wakeup(void);
441 extern void pm_wakeup_clear(bool reset);
442 extern void pm_system_irq_wakeup(unsigned int irq_number);
443 extern bool pm_get_wakeup_count(unsigned int *count, bool block);
444 extern bool pm_save_wakeup_count(unsigned int count);
445 extern void pm_wakep_autosleep_enabled(bool set);
446 extern void pm_print_active_wakeup_sources(void);
447 extern void pm_get_active_wakeup_sources(char *pending_sources, size_t max);
448 
lock_system_sleep(void)449 static inline void lock_system_sleep(void)
450 {
451 	current->flags |= PF_FREEZER_SKIP;
452 	mutex_lock(&pm_mutex);
453 }
454 
unlock_system_sleep(void)455 static inline void unlock_system_sleep(void)
456 {
457 	/*
458 	 * Don't use freezer_count() because we don't want the call to
459 	 * try_to_freeze() here.
460 	 *
461 	 * Reason:
462 	 * Fundamentally, we just don't need it, because freezing condition
463 	 * doesn't come into effect until we release the pm_mutex lock,
464 	 * since the freezer always works with pm_mutex held.
465 	 *
466 	 * More importantly, in the case of hibernation,
467 	 * unlock_system_sleep() gets called in snapshot_read() and
468 	 * snapshot_write() when the freezing condition is still in effect.
469 	 * Which means, if we use try_to_freeze() here, it would make them
470 	 * enter the refrigerator, thus causing hibernation to lockup.
471 	 */
472 	current->flags &= ~PF_FREEZER_SKIP;
473 	mutex_unlock(&pm_mutex);
474 }
475 
476 #else /* !CONFIG_PM_SLEEP */
477 
register_pm_notifier(struct notifier_block * nb)478 static inline int register_pm_notifier(struct notifier_block *nb)
479 {
480 	return 0;
481 }
482 
unregister_pm_notifier(struct notifier_block * nb)483 static inline int unregister_pm_notifier(struct notifier_block *nb)
484 {
485 	return 0;
486 }
487 
488 #define pm_notifier(fn, pri)	do { (void)(fn); } while (0)
489 
pm_wakeup_pending(void)490 static inline bool pm_wakeup_pending(void) { return false; }
pm_system_wakeup(void)491 static inline void pm_system_wakeup(void) {}
pm_wakeup_clear(bool reset)492 static inline void pm_wakeup_clear(bool reset) {}
pm_system_irq_wakeup(unsigned int irq_number)493 static inline void pm_system_irq_wakeup(unsigned int irq_number) {}
494 
lock_system_sleep(void)495 static inline void lock_system_sleep(void) {}
unlock_system_sleep(void)496 static inline void unlock_system_sleep(void) {}
497 
498 #endif /* !CONFIG_PM_SLEEP */
499 
500 #ifdef CONFIG_PM_SLEEP_DEBUG
501 extern bool pm_print_times_enabled;
502 extern bool pm_debug_messages_on;
503 extern __printf(2, 3) void __pm_pr_dbg(bool defer, const char *fmt, ...);
504 #else
505 #define pm_print_times_enabled	(false)
506 #define pm_debug_messages_on	(false)
507 
508 #include <linux/printk.h>
509 
510 #define __pm_pr_dbg(defer, fmt, ...) \
511 	no_printk(KERN_DEBUG fmt, ##__VA_ARGS__)
512 #endif
513 
514 #define pm_pr_dbg(fmt, ...) \
515 	__pm_pr_dbg(false, fmt, ##__VA_ARGS__)
516 
517 #define pm_deferred_pr_dbg(fmt, ...) \
518 	__pm_pr_dbg(true, fmt, ##__VA_ARGS__)
519 
520 #ifdef CONFIG_PM_AUTOSLEEP
521 
522 /* kernel/power/autosleep.c */
523 void queue_up_suspend_work(void);
524 
525 #else /* !CONFIG_PM_AUTOSLEEP */
526 
queue_up_suspend_work(void)527 static inline void queue_up_suspend_work(void) {}
528 
529 #endif /* !CONFIG_PM_AUTOSLEEP */
530 
531 #ifdef CONFIG_ARCH_SAVE_PAGE_KEYS
532 /*
533  * The ARCH_SAVE_PAGE_KEYS functions can be used by an architecture
534  * to save/restore additional information to/from the array of page
535  * frame numbers in the hibernation image. For s390 this is used to
536  * save and restore the storage key for each page that is included
537  * in the hibernation image.
538  */
539 unsigned long page_key_additional_pages(unsigned long pages);
540 int page_key_alloc(unsigned long pages);
541 void page_key_free(void);
542 void page_key_read(unsigned long *pfn);
543 void page_key_memorize(unsigned long *pfn);
544 void page_key_write(void *address);
545 
546 #else /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
547 
page_key_additional_pages(unsigned long pages)548 static inline unsigned long page_key_additional_pages(unsigned long pages)
549 {
550 	return 0;
551 }
552 
page_key_alloc(unsigned long pages)553 static inline int  page_key_alloc(unsigned long pages)
554 {
555 	return 0;
556 }
557 
page_key_free(void)558 static inline void page_key_free(void) {}
page_key_read(unsigned long * pfn)559 static inline void page_key_read(unsigned long *pfn) {}
page_key_memorize(unsigned long * pfn)560 static inline void page_key_memorize(unsigned long *pfn) {}
page_key_write(void * address)561 static inline void page_key_write(void *address) {}
562 
563 #endif /* !CONFIG_ARCH_SAVE_PAGE_KEYS */
564 
565 #endif /* _LINUX_SUSPEND_H */
566