xref: /openbmc/linux/kernel/power/power.h (revision 0b26ca68)
1  /* SPDX-License-Identifier: GPL-2.0 */
2  #include <linux/suspend.h>
3  #include <linux/suspend_ioctls.h>
4  #include <linux/utsname.h>
5  #include <linux/freezer.h>
6  #include <linux/compiler.h>
7  
8  struct swsusp_info {
9  	struct new_utsname	uts;
10  	u32			version_code;
11  	unsigned long		num_physpages;
12  	int			cpus;
13  	unsigned long		image_pages;
14  	unsigned long		pages;
15  	unsigned long		size;
16  } __aligned(PAGE_SIZE);
17  
18  #ifdef CONFIG_HIBERNATION
19  /* kernel/power/snapshot.c */
20  extern void __init hibernate_reserved_size_init(void);
21  extern void __init hibernate_image_size_init(void);
22  
23  #ifdef CONFIG_ARCH_HIBERNATION_HEADER
24  /* Maximum size of architecture specific data in a hibernation header */
25  #define MAX_ARCH_HEADER_SIZE	(sizeof(struct new_utsname) + 4)
26  
27  extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
28  extern int arch_hibernation_header_restore(void *addr);
29  
30  static inline int init_header_complete(struct swsusp_info *info)
31  {
32  	return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
33  }
34  
35  static inline const char *check_image_kernel(struct swsusp_info *info)
36  {
37  	return arch_hibernation_header_restore(info) ?
38  			"architecture specific data" : NULL;
39  }
40  #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
41  
42  extern int hibernate_resume_nonboot_cpu_disable(void);
43  
44  /*
45   * Keep some memory free so that I/O operations can succeed without paging
46   * [Might this be more than 4 MB?]
47   */
48  #define PAGES_FOR_IO	((4096 * 1024) >> PAGE_SHIFT)
49  
50  /*
51   * Keep 1 MB of memory free so that device drivers can allocate some pages in
52   * their .suspend() routines without breaking the suspend to disk.
53   */
54  #define SPARE_PAGES	((1024 * 1024) >> PAGE_SHIFT)
55  
56  asmlinkage int swsusp_save(void);
57  
58  /* kernel/power/hibernate.c */
59  extern bool freezer_test_done;
60  
61  extern int hibernation_snapshot(int platform_mode);
62  extern int hibernation_restore(int platform_mode);
63  extern int hibernation_platform_enter(void);
64  
65  #ifdef CONFIG_STRICT_KERNEL_RWX
66  /* kernel/power/snapshot.c */
67  extern void enable_restore_image_protection(void);
68  #else
69  static inline void enable_restore_image_protection(void) {}
70  #endif /* CONFIG_STRICT_KERNEL_RWX */
71  
72  #else /* !CONFIG_HIBERNATION */
73  
74  static inline void hibernate_reserved_size_init(void) {}
75  static inline void hibernate_image_size_init(void) {}
76  #endif /* !CONFIG_HIBERNATION */
77  
78  #define power_attr(_name) \
79  static struct kobj_attribute _name##_attr = {	\
80  	.attr	= {				\
81  		.name = __stringify(_name),	\
82  		.mode = 0644,			\
83  	},					\
84  	.show	= _name##_show,			\
85  	.store	= _name##_store,		\
86  }
87  
88  #define power_attr_ro(_name) \
89  static struct kobj_attribute _name##_attr = {	\
90  	.attr	= {				\
91  		.name = __stringify(_name),	\
92  		.mode = S_IRUGO,		\
93  	},					\
94  	.show	= _name##_show,			\
95  }
96  
97  /* Preferred image size in bytes (default 500 MB) */
98  extern unsigned long image_size;
99  /* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
100  extern unsigned long reserved_size;
101  extern int in_suspend;
102  extern dev_t swsusp_resume_device;
103  extern sector_t swsusp_resume_block;
104  
105  extern int create_basic_memory_bitmaps(void);
106  extern void free_basic_memory_bitmaps(void);
107  extern int hibernate_preallocate_memory(void);
108  
109  extern void clear_or_poison_free_pages(void);
110  
111  /**
112   *	Auxiliary structure used for reading the snapshot image data and
113   *	metadata from and writing them to the list of page backup entries
114   *	(PBEs) which is the main data structure of swsusp.
115   *
116   *	Using struct snapshot_handle we can transfer the image, including its
117   *	metadata, as a continuous sequence of bytes with the help of
118   *	snapshot_read_next() and snapshot_write_next().
119   *
120   *	The code that writes the image to a storage or transfers it to
121   *	the user land is required to use snapshot_read_next() for this
122   *	purpose and it should not make any assumptions regarding the internal
123   *	structure of the image.  Similarly, the code that reads the image from
124   *	a storage or transfers it from the user land is required to use
125   *	snapshot_write_next().
126   *
127   *	This may allow us to change the internal structure of the image
128   *	in the future with considerably less effort.
129   */
130  
131  struct snapshot_handle {
132  	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
133  				 * next operation will refer to (ie. current)
134  				 */
135  	void		*buffer;	/* address of the block to read from
136  					 * or write to
137  					 */
138  	int		sync_read;	/* Set to one to notify the caller of
139  					 * snapshot_write_next() that it may
140  					 * need to call wait_on_bio_chain()
141  					 */
142  };
143  
144  /* This macro returns the address from/to which the caller of
145   * snapshot_read_next()/snapshot_write_next() is allowed to
146   * read/write data after the function returns
147   */
148  #define data_of(handle)	((handle).buffer)
149  
150  extern unsigned int snapshot_additional_pages(struct zone *zone);
151  extern unsigned long snapshot_get_image_size(void);
152  extern int snapshot_read_next(struct snapshot_handle *handle);
153  extern int snapshot_write_next(struct snapshot_handle *handle);
154  extern void snapshot_write_finalize(struct snapshot_handle *handle);
155  extern int snapshot_image_loaded(struct snapshot_handle *handle);
156  
157  extern bool hibernate_acquire(void);
158  extern void hibernate_release(void);
159  
160  extern sector_t alloc_swapdev_block(int swap);
161  extern void free_all_swap_pages(int swap);
162  extern int swsusp_swap_in_use(void);
163  
164  /*
165   * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
166   * the image header.
167   */
168  #define SF_PLATFORM_MODE	1
169  #define SF_NOCOMPRESS_MODE	2
170  #define SF_CRC32_MODE	        4
171  
172  /* kernel/power/hibernate.c */
173  extern int swsusp_check(void);
174  extern void swsusp_free(void);
175  extern int swsusp_read(unsigned int *flags_p);
176  extern int swsusp_write(unsigned int flags);
177  extern void swsusp_close(fmode_t);
178  #ifdef CONFIG_SUSPEND
179  extern int swsusp_unmark(void);
180  #endif
181  
182  struct __kernel_old_timeval;
183  /* kernel/power/swsusp.c */
184  extern void swsusp_show_speed(ktime_t, ktime_t, unsigned int, char *);
185  
186  #ifdef CONFIG_SUSPEND
187  /* kernel/power/suspend.c */
188  extern const char * const pm_labels[];
189  extern const char *pm_states[];
190  extern const char *mem_sleep_states[];
191  
192  extern int suspend_devices_and_enter(suspend_state_t state);
193  #else /* !CONFIG_SUSPEND */
194  #define mem_sleep_current	PM_SUSPEND_ON
195  
196  static inline int suspend_devices_and_enter(suspend_state_t state)
197  {
198  	return -ENOSYS;
199  }
200  #endif /* !CONFIG_SUSPEND */
201  
202  #ifdef CONFIG_PM_TEST_SUSPEND
203  /* kernel/power/suspend_test.c */
204  extern void suspend_test_start(void);
205  extern void suspend_test_finish(const char *label);
206  #else /* !CONFIG_PM_TEST_SUSPEND */
207  static inline void suspend_test_start(void) {}
208  static inline void suspend_test_finish(const char *label) {}
209  #endif /* !CONFIG_PM_TEST_SUSPEND */
210  
211  #ifdef CONFIG_PM_SLEEP
212  /* kernel/power/main.c */
213  extern int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down);
214  extern int pm_notifier_call_chain(unsigned long val);
215  #endif
216  
217  #ifdef CONFIG_HIGHMEM
218  int restore_highmem(void);
219  #else
220  static inline unsigned int count_highmem_pages(void) { return 0; }
221  static inline int restore_highmem(void) { return 0; }
222  #endif
223  
224  /*
225   * Suspend test levels
226   */
227  enum {
228  	/* keep first */
229  	TEST_NONE,
230  	TEST_CORE,
231  	TEST_CPUS,
232  	TEST_PLATFORM,
233  	TEST_DEVICES,
234  	TEST_FREEZER,
235  	/* keep last */
236  	__TEST_AFTER_LAST
237  };
238  
239  #define TEST_FIRST	TEST_NONE
240  #define TEST_MAX	(__TEST_AFTER_LAST - 1)
241  
242  #ifdef CONFIG_PM_SLEEP_DEBUG
243  extern int pm_test_level;
244  #else
245  #define pm_test_level	(TEST_NONE)
246  #endif
247  
248  #ifdef CONFIG_SUSPEND_FREEZER
249  static inline int suspend_freeze_processes(void)
250  {
251  	int error;
252  
253  	error = freeze_processes();
254  	/*
255  	 * freeze_processes() automatically thaws every task if freezing
256  	 * fails. So we need not do anything extra upon error.
257  	 */
258  	if (error)
259  		return error;
260  
261  	error = freeze_kernel_threads();
262  	/*
263  	 * freeze_kernel_threads() thaws only kernel threads upon freezing
264  	 * failure. So we have to thaw the userspace tasks ourselves.
265  	 */
266  	if (error)
267  		thaw_processes();
268  
269  	return error;
270  }
271  
272  static inline void suspend_thaw_processes(void)
273  {
274  	thaw_processes();
275  }
276  #else
277  static inline int suspend_freeze_processes(void)
278  {
279  	return 0;
280  }
281  
282  static inline void suspend_thaw_processes(void)
283  {
284  }
285  #endif
286  
287  #ifdef CONFIG_PM_AUTOSLEEP
288  
289  /* kernel/power/autosleep.c */
290  extern int pm_autosleep_init(void);
291  extern int pm_autosleep_lock(void);
292  extern void pm_autosleep_unlock(void);
293  extern suspend_state_t pm_autosleep_state(void);
294  extern int pm_autosleep_set_state(suspend_state_t state);
295  
296  #else /* !CONFIG_PM_AUTOSLEEP */
297  
298  static inline int pm_autosleep_init(void) { return 0; }
299  static inline int pm_autosleep_lock(void) { return 0; }
300  static inline void pm_autosleep_unlock(void) {}
301  static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
302  
303  #endif /* !CONFIG_PM_AUTOSLEEP */
304  
305  #ifdef CONFIG_PM_WAKELOCKS
306  
307  /* kernel/power/wakelock.c */
308  extern ssize_t pm_show_wakelocks(char *buf, bool show_active);
309  extern int pm_wake_lock(const char *buf);
310  extern int pm_wake_unlock(const char *buf);
311  
312  #endif /* !CONFIG_PM_WAKELOCKS */
313