xref: /openbmc/linux/kernel/power/power.h (revision 6aeadf78)
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 #include <linux/cpu.h>
8 #include <linux/cpuidle.h>
9 
10 struct swsusp_info {
11 	struct new_utsname	uts;
12 	u32			version_code;
13 	unsigned long		num_physpages;
14 	int			cpus;
15 	unsigned long		image_pages;
16 	unsigned long		pages;
17 	unsigned long		size;
18 } __aligned(PAGE_SIZE);
19 
20 #ifdef CONFIG_HIBERNATION
21 /* kernel/power/snapshot.c */
22 extern void __init hibernate_reserved_size_init(void);
23 extern void __init hibernate_image_size_init(void);
24 
25 #ifdef CONFIG_ARCH_HIBERNATION_HEADER
26 /* Maximum size of architecture specific data in a hibernation header */
27 #define MAX_ARCH_HEADER_SIZE	(sizeof(struct new_utsname) + 4)
28 
29 static inline int init_header_complete(struct swsusp_info *info)
30 {
31 	return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
32 }
33 
34 static inline const char *check_image_kernel(struct swsusp_info *info)
35 {
36 	return arch_hibernation_header_restore(info) ?
37 			"architecture specific data" : NULL;
38 }
39 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
40 
41 /*
42  * Keep some memory free so that I/O operations can succeed without paging
43  * [Might this be more than 4 MB?]
44  */
45 #define PAGES_FOR_IO	((4096 * 1024) >> PAGE_SHIFT)
46 
47 /*
48  * Keep 1 MB of memory free so that device drivers can allocate some pages in
49  * their .suspend() routines without breaking the suspend to disk.
50  */
51 #define SPARE_PAGES	((1024 * 1024) >> PAGE_SHIFT)
52 
53 asmlinkage int swsusp_save(void);
54 
55 /* kernel/power/hibernate.c */
56 extern bool freezer_test_done;
57 
58 extern int hibernation_snapshot(int platform_mode);
59 extern int hibernation_restore(int platform_mode);
60 extern int hibernation_platform_enter(void);
61 
62 #ifdef CONFIG_STRICT_KERNEL_RWX
63 /* kernel/power/snapshot.c */
64 extern void enable_restore_image_protection(void);
65 #else
66 static inline void enable_restore_image_protection(void) {}
67 #endif /* CONFIG_STRICT_KERNEL_RWX */
68 
69 #else /* !CONFIG_HIBERNATION */
70 
71 static inline void hibernate_reserved_size_init(void) {}
72 static inline void hibernate_image_size_init(void) {}
73 #endif /* !CONFIG_HIBERNATION */
74 
75 #define power_attr(_name) \
76 static struct kobj_attribute _name##_attr = {	\
77 	.attr	= {				\
78 		.name = __stringify(_name),	\
79 		.mode = 0644,			\
80 	},					\
81 	.show	= _name##_show,			\
82 	.store	= _name##_store,		\
83 }
84 
85 #define power_attr_ro(_name) \
86 static struct kobj_attribute _name##_attr = {	\
87 	.attr	= {				\
88 		.name = __stringify(_name),	\
89 		.mode = S_IRUGO,		\
90 	},					\
91 	.show	= _name##_show,			\
92 }
93 
94 /* Preferred image size in bytes (default 500 MB) */
95 extern unsigned long image_size;
96 /* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
97 extern unsigned long reserved_size;
98 extern int in_suspend;
99 extern dev_t swsusp_resume_device;
100 extern sector_t swsusp_resume_block;
101 
102 extern int create_basic_memory_bitmaps(void);
103 extern void free_basic_memory_bitmaps(void);
104 extern int hibernate_preallocate_memory(void);
105 
106 extern void clear_or_poison_free_pages(void);
107 
108 /**
109  *	Auxiliary structure used for reading the snapshot image data and
110  *	metadata from and writing them to the list of page backup entries
111  *	(PBEs) which is the main data structure of swsusp.
112  *
113  *	Using struct snapshot_handle we can transfer the image, including its
114  *	metadata, as a continuous sequence of bytes with the help of
115  *	snapshot_read_next() and snapshot_write_next().
116  *
117  *	The code that writes the image to a storage or transfers it to
118  *	the user land is required to use snapshot_read_next() for this
119  *	purpose and it should not make any assumptions regarding the internal
120  *	structure of the image.  Similarly, the code that reads the image from
121  *	a storage or transfers it from the user land is required to use
122  *	snapshot_write_next().
123  *
124  *	This may allow us to change the internal structure of the image
125  *	in the future with considerably less effort.
126  */
127 
128 struct snapshot_handle {
129 	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
130 				 * next operation will refer to (ie. current)
131 				 */
132 	void		*buffer;	/* address of the block to read from
133 					 * or write to
134 					 */
135 	int		sync_read;	/* Set to one to notify the caller of
136 					 * snapshot_write_next() that it may
137 					 * need to call wait_on_bio_chain()
138 					 */
139 };
140 
141 /* This macro returns the address from/to which the caller of
142  * snapshot_read_next()/snapshot_write_next() is allowed to
143  * read/write data after the function returns
144  */
145 #define data_of(handle)	((handle).buffer)
146 
147 extern unsigned int snapshot_additional_pages(struct zone *zone);
148 extern unsigned long snapshot_get_image_size(void);
149 extern int snapshot_read_next(struct snapshot_handle *handle);
150 extern int snapshot_write_next(struct snapshot_handle *handle);
151 extern void snapshot_write_finalize(struct snapshot_handle *handle);
152 extern int snapshot_image_loaded(struct snapshot_handle *handle);
153 
154 extern bool hibernate_acquire(void);
155 extern void hibernate_release(void);
156 
157 extern sector_t alloc_swapdev_block(int swap);
158 extern void free_all_swap_pages(int swap);
159 extern int swsusp_swap_in_use(void);
160 
161 /*
162  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
163  * the image header.
164  */
165 #define SF_PLATFORM_MODE	1
166 #define SF_NOCOMPRESS_MODE	2
167 #define SF_CRC32_MODE	        4
168 #define SF_HW_SIG		8
169 
170 /* kernel/power/hibernate.c */
171 int swsusp_check(bool snapshot_test);
172 extern void swsusp_free(void);
173 extern int swsusp_read(unsigned int *flags_p);
174 extern int swsusp_write(unsigned int flags);
175 void swsusp_close(bool snapshot_test);
176 #ifdef CONFIG_SUSPEND
177 extern int swsusp_unmark(void);
178 #endif
179 
180 struct __kernel_old_timeval;
181 /* kernel/power/swsusp.c */
182 extern void swsusp_show_speed(ktime_t, ktime_t, unsigned int, char *);
183 
184 #ifdef CONFIG_SUSPEND
185 /* kernel/power/suspend.c */
186 extern const char * const pm_labels[];
187 extern const char *pm_states[];
188 extern const char *mem_sleep_states[];
189 
190 extern int suspend_devices_and_enter(suspend_state_t state);
191 #else /* !CONFIG_SUSPEND */
192 #define mem_sleep_current	PM_SUSPEND_ON
193 
194 static inline int suspend_devices_and_enter(suspend_state_t state)
195 {
196 	return -ENOSYS;
197 }
198 #endif /* !CONFIG_SUSPEND */
199 
200 #ifdef CONFIG_PM_TEST_SUSPEND
201 /* kernel/power/suspend_test.c */
202 extern void suspend_test_start(void);
203 extern void suspend_test_finish(const char *label);
204 #else /* !CONFIG_PM_TEST_SUSPEND */
205 static inline void suspend_test_start(void) {}
206 static inline void suspend_test_finish(const char *label) {}
207 #endif /* !CONFIG_PM_TEST_SUSPEND */
208 
209 #ifdef CONFIG_PM_SLEEP
210 /* kernel/power/main.c */
211 extern int pm_notifier_call_chain_robust(unsigned long val_up, unsigned long val_down);
212 extern int pm_notifier_call_chain(unsigned long val);
213 #endif
214 
215 #ifdef CONFIG_HIGHMEM
216 int restore_highmem(void);
217 #else
218 static inline unsigned int count_highmem_pages(void) { return 0; }
219 static inline int restore_highmem(void) { return 0; }
220 #endif
221 
222 /*
223  * Suspend test levels
224  */
225 enum {
226 	/* keep first */
227 	TEST_NONE,
228 	TEST_CORE,
229 	TEST_CPUS,
230 	TEST_PLATFORM,
231 	TEST_DEVICES,
232 	TEST_FREEZER,
233 	/* keep last */
234 	__TEST_AFTER_LAST
235 };
236 
237 #define TEST_FIRST	TEST_NONE
238 #define TEST_MAX	(__TEST_AFTER_LAST - 1)
239 
240 #ifdef CONFIG_PM_SLEEP_DEBUG
241 extern int pm_test_level;
242 #else
243 #define pm_test_level	(TEST_NONE)
244 #endif
245 
246 #ifdef CONFIG_SUSPEND_FREEZER
247 static inline int suspend_freeze_processes(void)
248 {
249 	int error;
250 
251 	error = freeze_processes();
252 	/*
253 	 * freeze_processes() automatically thaws every task if freezing
254 	 * fails. So we need not do anything extra upon error.
255 	 */
256 	if (error)
257 		return error;
258 
259 	error = freeze_kernel_threads();
260 	/*
261 	 * freeze_kernel_threads() thaws only kernel threads upon freezing
262 	 * failure. So we have to thaw the userspace tasks ourselves.
263 	 */
264 	if (error)
265 		thaw_processes();
266 
267 	return error;
268 }
269 
270 static inline void suspend_thaw_processes(void)
271 {
272 	thaw_processes();
273 }
274 #else
275 static inline int suspend_freeze_processes(void)
276 {
277 	return 0;
278 }
279 
280 static inline void suspend_thaw_processes(void)
281 {
282 }
283 #endif
284 
285 #ifdef CONFIG_PM_AUTOSLEEP
286 
287 /* kernel/power/autosleep.c */
288 extern int pm_autosleep_init(void);
289 extern int pm_autosleep_lock(void);
290 extern void pm_autosleep_unlock(void);
291 extern suspend_state_t pm_autosleep_state(void);
292 extern int pm_autosleep_set_state(suspend_state_t state);
293 
294 #else /* !CONFIG_PM_AUTOSLEEP */
295 
296 static inline int pm_autosleep_init(void) { return 0; }
297 static inline int pm_autosleep_lock(void) { return 0; }
298 static inline void pm_autosleep_unlock(void) {}
299 static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
300 
301 #endif /* !CONFIG_PM_AUTOSLEEP */
302 
303 #ifdef CONFIG_PM_WAKELOCKS
304 
305 /* kernel/power/wakelock.c */
306 extern ssize_t pm_show_wakelocks(char *buf, bool show_active);
307 extern int pm_wake_lock(const char *buf);
308 extern int pm_wake_unlock(const char *buf);
309 
310 #endif /* !CONFIG_PM_WAKELOCKS */
311 
312 static inline int pm_sleep_disable_secondary_cpus(void)
313 {
314 	cpuidle_pause();
315 	return suspend_disable_secondary_cpus();
316 }
317 
318 static inline void pm_sleep_enable_secondary_cpus(void)
319 {
320 	suspend_enable_secondary_cpus();
321 	cpuidle_resume();
322 }
323