xref: /openbmc/linux/kernel/power/power.h (revision ecd25094)
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 #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_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 /* If unset, the snapshot device cannot be open. */
158 extern atomic_t snapshot_device_available;
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 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(unsigned long val, int nr_to_call,
214 				    int *nr_calls);
215 extern int pm_notifier_call_chain(unsigned long val);
216 #endif
217 
218 #ifdef CONFIG_HIGHMEM
219 int restore_highmem(void);
220 #else
221 static inline unsigned int count_highmem_pages(void) { return 0; }
222 static inline int restore_highmem(void) { return 0; }
223 #endif
224 
225 /*
226  * Suspend test levels
227  */
228 enum {
229 	/* keep first */
230 	TEST_NONE,
231 	TEST_CORE,
232 	TEST_CPUS,
233 	TEST_PLATFORM,
234 	TEST_DEVICES,
235 	TEST_FREEZER,
236 	/* keep last */
237 	__TEST_AFTER_LAST
238 };
239 
240 #define TEST_FIRST	TEST_NONE
241 #define TEST_MAX	(__TEST_AFTER_LAST - 1)
242 
243 #ifdef CONFIG_PM_SLEEP_DEBUG
244 extern int pm_test_level;
245 #else
246 #define pm_test_level	(TEST_NONE)
247 #endif
248 
249 #ifdef CONFIG_SUSPEND_FREEZER
250 static inline int suspend_freeze_processes(void)
251 {
252 	int error;
253 
254 	error = freeze_processes();
255 	/*
256 	 * freeze_processes() automatically thaws every task if freezing
257 	 * fails. So we need not do anything extra upon error.
258 	 */
259 	if (error)
260 		return error;
261 
262 	error = freeze_kernel_threads();
263 	/*
264 	 * freeze_kernel_threads() thaws only kernel threads upon freezing
265 	 * failure. So we have to thaw the userspace tasks ourselves.
266 	 */
267 	if (error)
268 		thaw_processes();
269 
270 	return error;
271 }
272 
273 static inline void suspend_thaw_processes(void)
274 {
275 	thaw_processes();
276 }
277 #else
278 static inline int suspend_freeze_processes(void)
279 {
280 	return 0;
281 }
282 
283 static inline void suspend_thaw_processes(void)
284 {
285 }
286 #endif
287 
288 #ifdef CONFIG_PM_AUTOSLEEP
289 
290 /* kernel/power/autosleep.c */
291 extern int pm_autosleep_init(void);
292 extern int pm_autosleep_lock(void);
293 extern void pm_autosleep_unlock(void);
294 extern suspend_state_t pm_autosleep_state(void);
295 extern int pm_autosleep_set_state(suspend_state_t state);
296 
297 #else /* !CONFIG_PM_AUTOSLEEP */
298 
299 static inline int pm_autosleep_init(void) { return 0; }
300 static inline int pm_autosleep_lock(void) { return 0; }
301 static inline void pm_autosleep_unlock(void) {}
302 static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
303 
304 #endif /* !CONFIG_PM_AUTOSLEEP */
305 
306 #ifdef CONFIG_PM_WAKELOCKS
307 
308 /* kernel/power/wakelock.c */
309 extern ssize_t pm_show_wakelocks(char *buf, bool show_active);
310 extern int pm_wake_lock(const char *buf);
311 extern int pm_wake_unlock(const char *buf);
312 
313 #endif /* !CONFIG_PM_WAKELOCKS */
314