xref: /openbmc/linux/kernel/power/power.h (revision ae213c44)
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 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 extern int pfn_is_nosave(unsigned long);
79 
80 #define power_attr(_name) \
81 static struct kobj_attribute _name##_attr = {	\
82 	.attr	= {				\
83 		.name = __stringify(_name),	\
84 		.mode = 0644,			\
85 	},					\
86 	.show	= _name##_show,			\
87 	.store	= _name##_store,		\
88 }
89 
90 #define power_attr_ro(_name) \
91 static struct kobj_attribute _name##_attr = {	\
92 	.attr	= {				\
93 		.name = __stringify(_name),	\
94 		.mode = S_IRUGO,		\
95 	},					\
96 	.show	= _name##_show,			\
97 }
98 
99 /* Preferred image size in bytes (default 500 MB) */
100 extern unsigned long image_size;
101 /* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
102 extern unsigned long reserved_size;
103 extern int in_suspend;
104 extern dev_t swsusp_resume_device;
105 extern sector_t swsusp_resume_block;
106 
107 extern int create_basic_memory_bitmaps(void);
108 extern void free_basic_memory_bitmaps(void);
109 extern int hibernate_preallocate_memory(void);
110 
111 extern void clear_free_pages(void);
112 
113 /**
114  *	Auxiliary structure used for reading the snapshot image data and
115  *	metadata from and writing them to the list of page backup entries
116  *	(PBEs) which is the main data structure of swsusp.
117  *
118  *	Using struct snapshot_handle we can transfer the image, including its
119  *	metadata, as a continuous sequence of bytes with the help of
120  *	snapshot_read_next() and snapshot_write_next().
121  *
122  *	The code that writes the image to a storage or transfers it to
123  *	the user land is required to use snapshot_read_next() for this
124  *	purpose and it should not make any assumptions regarding the internal
125  *	structure of the image.  Similarly, the code that reads the image from
126  *	a storage or transfers it from the user land is required to use
127  *	snapshot_write_next().
128  *
129  *	This may allow us to change the internal structure of the image
130  *	in the future with considerably less effort.
131  */
132 
133 struct snapshot_handle {
134 	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
135 				 * next operation will refer to (ie. current)
136 				 */
137 	void		*buffer;	/* address of the block to read from
138 					 * or write to
139 					 */
140 	int		sync_read;	/* Set to one to notify the caller of
141 					 * snapshot_write_next() that it may
142 					 * need to call wait_on_bio_chain()
143 					 */
144 };
145 
146 /* This macro returns the address from/to which the caller of
147  * snapshot_read_next()/snapshot_write_next() is allowed to
148  * read/write data after the function returns
149  */
150 #define data_of(handle)	((handle).buffer)
151 
152 extern unsigned int snapshot_additional_pages(struct zone *zone);
153 extern unsigned long snapshot_get_image_size(void);
154 extern int snapshot_read_next(struct snapshot_handle *handle);
155 extern int snapshot_write_next(struct snapshot_handle *handle);
156 extern void snapshot_write_finalize(struct snapshot_handle *handle);
157 extern int snapshot_image_loaded(struct snapshot_handle *handle);
158 
159 /* If unset, the snapshot device cannot be open. */
160 extern atomic_t snapshot_device_available;
161 
162 extern sector_t alloc_swapdev_block(int swap);
163 extern void free_all_swap_pages(int swap);
164 extern int swsusp_swap_in_use(void);
165 
166 /*
167  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
168  * the image header.
169  */
170 #define SF_PLATFORM_MODE	1
171 #define SF_NOCOMPRESS_MODE	2
172 #define SF_CRC32_MODE	        4
173 
174 /* kernel/power/hibernate.c */
175 extern int swsusp_check(void);
176 extern void swsusp_free(void);
177 extern int swsusp_read(unsigned int *flags_p);
178 extern int swsusp_write(unsigned int flags);
179 extern void swsusp_close(fmode_t);
180 #ifdef CONFIG_SUSPEND
181 extern int swsusp_unmark(void);
182 #endif
183 
184 struct timeval;
185 /* kernel/power/swsusp.c */
186 extern void swsusp_show_speed(ktime_t, ktime_t, unsigned int, char *);
187 
188 #ifdef CONFIG_SUSPEND
189 /* kernel/power/suspend.c */
190 extern const char * const pm_labels[];
191 extern const char *pm_states[];
192 extern const char *mem_sleep_states[];
193 
194 extern int suspend_devices_and_enter(suspend_state_t state);
195 #else /* !CONFIG_SUSPEND */
196 #define mem_sleep_current	PM_SUSPEND_ON
197 
198 static inline int suspend_devices_and_enter(suspend_state_t state)
199 {
200 	return -ENOSYS;
201 }
202 #endif /* !CONFIG_SUSPEND */
203 
204 #ifdef CONFIG_PM_TEST_SUSPEND
205 /* kernel/power/suspend_test.c */
206 extern void suspend_test_start(void);
207 extern void suspend_test_finish(const char *label);
208 #else /* !CONFIG_PM_TEST_SUSPEND */
209 static inline void suspend_test_start(void) {}
210 static inline void suspend_test_finish(const char *label) {}
211 #endif /* !CONFIG_PM_TEST_SUSPEND */
212 
213 #ifdef CONFIG_PM_SLEEP
214 /* kernel/power/main.c */
215 extern int __pm_notifier_call_chain(unsigned long val, int nr_to_call,
216 				    int *nr_calls);
217 extern int pm_notifier_call_chain(unsigned long val);
218 #endif
219 
220 #ifdef CONFIG_HIGHMEM
221 int restore_highmem(void);
222 #else
223 static inline unsigned int count_highmem_pages(void) { return 0; }
224 static inline int restore_highmem(void) { return 0; }
225 #endif
226 
227 /*
228  * Suspend test levels
229  */
230 enum {
231 	/* keep first */
232 	TEST_NONE,
233 	TEST_CORE,
234 	TEST_CPUS,
235 	TEST_PLATFORM,
236 	TEST_DEVICES,
237 	TEST_FREEZER,
238 	/* keep last */
239 	__TEST_AFTER_LAST
240 };
241 
242 #define TEST_FIRST	TEST_NONE
243 #define TEST_MAX	(__TEST_AFTER_LAST - 1)
244 
245 #ifdef CONFIG_PM_SLEEP_DEBUG
246 extern int pm_test_level;
247 #else
248 #define pm_test_level	(TEST_NONE)
249 #endif
250 
251 #ifdef CONFIG_SUSPEND_FREEZER
252 static inline int suspend_freeze_processes(void)
253 {
254 	int error;
255 
256 	error = freeze_processes();
257 	/*
258 	 * freeze_processes() automatically thaws every task if freezing
259 	 * fails. So we need not do anything extra upon error.
260 	 */
261 	if (error)
262 		return error;
263 
264 	error = freeze_kernel_threads();
265 	/*
266 	 * freeze_kernel_threads() thaws only kernel threads upon freezing
267 	 * failure. So we have to thaw the userspace tasks ourselves.
268 	 */
269 	if (error)
270 		thaw_processes();
271 
272 	return error;
273 }
274 
275 static inline void suspend_thaw_processes(void)
276 {
277 	thaw_processes();
278 }
279 #else
280 static inline int suspend_freeze_processes(void)
281 {
282 	return 0;
283 }
284 
285 static inline void suspend_thaw_processes(void)
286 {
287 }
288 #endif
289 
290 #ifdef CONFIG_PM_AUTOSLEEP
291 
292 /* kernel/power/autosleep.c */
293 extern int pm_autosleep_init(void);
294 extern int pm_autosleep_lock(void);
295 extern void pm_autosleep_unlock(void);
296 extern suspend_state_t pm_autosleep_state(void);
297 extern int pm_autosleep_set_state(suspend_state_t state);
298 
299 #else /* !CONFIG_PM_AUTOSLEEP */
300 
301 static inline int pm_autosleep_init(void) { return 0; }
302 static inline int pm_autosleep_lock(void) { return 0; }
303 static inline void pm_autosleep_unlock(void) {}
304 static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
305 
306 #endif /* !CONFIG_PM_AUTOSLEEP */
307 
308 #ifdef CONFIG_PM_WAKELOCKS
309 
310 /* kernel/power/wakelock.c */
311 extern ssize_t pm_show_wakelocks(char *buf, bool show_active);
312 extern int pm_wake_lock(const char *buf);
313 extern int pm_wake_unlock(const char *buf);
314 
315 #endif /* !CONFIG_PM_WAKELOCKS */
316