xref: /openbmc/linux/kernel/power/power.h (revision 44ad3baf1cca483e418b6aadf2d3994f69e0f16a)
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 
init_header_complete(struct swsusp_info * info)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 
check_image_kernel(struct swsusp_info * info)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
enable_restore_image_protection(void)66 static inline void enable_restore_image_protection(void) {}
67 #endif /* CONFIG_STRICT_KERNEL_RWX */
68 
69 extern bool hibernation_in_progress(void);
70 
71 #else /* !CONFIG_HIBERNATION */
72 
hibernate_reserved_size_init(void)73 static inline void hibernate_reserved_size_init(void) {}
hibernate_image_size_init(void)74 static inline void hibernate_image_size_init(void) {}
75 
hibernation_in_progress(void)76 static inline bool hibernation_in_progress(void) { return false; }
77 #endif /* !CONFIG_HIBERNATION */
78 
79 #define power_attr(_name) \
80 static struct kobj_attribute _name##_attr = {	\
81 	.attr	= {				\
82 		.name = __stringify(_name),	\
83 		.mode = 0644,			\
84 	},					\
85 	.show	= _name##_show,			\
86 	.store	= _name##_store,		\
87 }
88 
89 #define power_attr_ro(_name) \
90 static struct kobj_attribute _name##_attr = {	\
91 	.attr	= {				\
92 		.name = __stringify(_name),	\
93 		.mode = S_IRUGO,		\
94 	},					\
95 	.show	= _name##_show,			\
96 }
97 
98 /* Preferred image size in bytes (default 500 MB) */
99 extern unsigned long image_size;
100 /* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
101 extern unsigned long reserved_size;
102 extern int in_suspend;
103 extern dev_t swsusp_resume_device;
104 extern sector_t swsusp_resume_block;
105 
106 extern int create_basic_memory_bitmaps(void);
107 extern void free_basic_memory_bitmaps(void);
108 extern int hibernate_preallocate_memory(void);
109 
110 extern void clear_or_poison_free_pages(void);
111 
112 /**
113  *	Auxiliary structure used for reading the snapshot image data and
114  *	metadata from and writing them to the list of page backup entries
115  *	(PBEs) which is the main data structure of swsusp.
116  *
117  *	Using struct snapshot_handle we can transfer the image, including its
118  *	metadata, as a continuous sequence of bytes with the help of
119  *	snapshot_read_next() and snapshot_write_next().
120  *
121  *	The code that writes the image to a storage or transfers it to
122  *	the user land is required to use snapshot_read_next() for this
123  *	purpose and it should not make any assumptions regarding the internal
124  *	structure of the image.  Similarly, the code that reads the image from
125  *	a storage or transfers it from the user land is required to use
126  *	snapshot_write_next().
127  *
128  *	This may allow us to change the internal structure of the image
129  *	in the future with considerably less effort.
130  */
131 
132 struct snapshot_handle {
133 	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
134 				 * next operation will refer to (ie. current)
135 				 */
136 	void		*buffer;	/* address of the block to read from
137 					 * or write to
138 					 */
139 	int		sync_read;	/* Set to one to notify the caller of
140 					 * snapshot_write_next() that it may
141 					 * need to call wait_on_bio_chain()
142 					 */
143 };
144 
145 /* This macro returns the address from/to which the caller of
146  * snapshot_read_next()/snapshot_write_next() is allowed to
147  * read/write data after the function returns
148  */
149 #define data_of(handle)	((handle).buffer)
150 
151 extern unsigned int snapshot_additional_pages(struct zone *zone);
152 extern unsigned long snapshot_get_image_size(void);
153 extern int snapshot_read_next(struct snapshot_handle *handle);
154 extern int snapshot_write_next(struct snapshot_handle *handle);
155 extern void snapshot_write_finalize(struct snapshot_handle *handle);
156 extern int snapshot_image_loaded(struct snapshot_handle *handle);
157 
158 extern bool hibernate_acquire(void);
159 extern void hibernate_release(void);
160 
161 extern sector_t alloc_swapdev_block(int swap);
162 extern void free_all_swap_pages(int swap);
163 extern int swsusp_swap_in_use(void);
164 
165 /*
166  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
167  * the image header.
168  */
169 #define SF_PLATFORM_MODE	1
170 #define SF_NOCOMPRESS_MODE	2
171 #define SF_CRC32_MODE	        4
172 #define SF_HW_SIG		8
173 
174 /* kernel/power/hibernate.c */
175 int swsusp_check(bool exclusive);
176 extern void swsusp_free(void);
177 extern int swsusp_read(unsigned int *flags_p);
178 extern int swsusp_write(unsigned int flags);
179 void swsusp_close(bool exclusive);
180 #ifdef CONFIG_SUSPEND
181 extern int swsusp_unmark(void);
182 #endif
183 
184 struct __kernel_old_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 
suspend_devices_and_enter(suspend_state_t state)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 */
suspend_test_start(void)209 static inline void suspend_test_start(void) {}
suspend_test_finish(const char * label)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_robust(unsigned long val_up, unsigned long val_down);
216 extern int pm_notifier_call_chain(unsigned long val);
217 void pm_restrict_gfp_mask(void);
218 void pm_restore_gfp_mask(void);
219 #else
pm_restrict_gfp_mask(void)220 static inline void pm_restrict_gfp_mask(void) {}
pm_restore_gfp_mask(void)221 static inline void pm_restore_gfp_mask(void) {}
222 #endif
223 
224 #ifdef CONFIG_HIGHMEM
225 int restore_highmem(void);
226 #else
count_highmem_pages(void)227 static inline unsigned int count_highmem_pages(void) { return 0; }
restore_highmem(void)228 static inline int restore_highmem(void) { return 0; }
229 #endif
230 
231 /*
232  * Suspend test levels
233  */
234 enum {
235 	/* keep first */
236 	TEST_NONE,
237 	TEST_CORE,
238 	TEST_CPUS,
239 	TEST_PLATFORM,
240 	TEST_DEVICES,
241 	TEST_FREEZER,
242 	/* keep last */
243 	__TEST_AFTER_LAST
244 };
245 
246 #define TEST_FIRST	TEST_NONE
247 #define TEST_MAX	(__TEST_AFTER_LAST - 1)
248 
249 #ifdef CONFIG_PM_SLEEP_DEBUG
250 extern int pm_test_level;
251 #else
252 #define pm_test_level	(TEST_NONE)
253 #endif
254 
255 #ifdef CONFIG_SUSPEND_FREEZER
suspend_freeze_processes(void)256 static inline int suspend_freeze_processes(void)
257 {
258 	int error;
259 
260 	error = freeze_processes();
261 	/*
262 	 * freeze_processes() automatically thaws every task if freezing
263 	 * fails. So we need not do anything extra upon error.
264 	 */
265 	if (error)
266 		return error;
267 
268 	error = freeze_kernel_threads();
269 	/*
270 	 * freeze_kernel_threads() thaws only kernel threads upon freezing
271 	 * failure. So we have to thaw the userspace tasks ourselves.
272 	 */
273 	if (error)
274 		thaw_processes();
275 
276 	return error;
277 }
278 
suspend_thaw_processes(void)279 static inline void suspend_thaw_processes(void)
280 {
281 	thaw_processes();
282 }
283 #else
suspend_freeze_processes(void)284 static inline int suspend_freeze_processes(void)
285 {
286 	return 0;
287 }
288 
suspend_thaw_processes(void)289 static inline void suspend_thaw_processes(void)
290 {
291 }
292 #endif
293 
294 #ifdef CONFIG_PM_AUTOSLEEP
295 
296 /* kernel/power/autosleep.c */
297 extern int pm_autosleep_init(void);
298 extern int pm_autosleep_lock(void);
299 extern void pm_autosleep_unlock(void);
300 extern suspend_state_t pm_autosleep_state(void);
301 extern int pm_autosleep_set_state(suspend_state_t state);
302 
303 #else /* !CONFIG_PM_AUTOSLEEP */
304 
pm_autosleep_init(void)305 static inline int pm_autosleep_init(void) { return 0; }
pm_autosleep_lock(void)306 static inline int pm_autosleep_lock(void) { return 0; }
pm_autosleep_unlock(void)307 static inline void pm_autosleep_unlock(void) {}
pm_autosleep_state(void)308 static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
309 
310 #endif /* !CONFIG_PM_AUTOSLEEP */
311 
312 #ifdef CONFIG_PM_WAKELOCKS
313 
314 /* kernel/power/wakelock.c */
315 extern ssize_t pm_show_wakelocks(char *buf, bool show_active);
316 extern int pm_wake_lock(const char *buf);
317 extern int pm_wake_unlock(const char *buf);
318 
319 #endif /* !CONFIG_PM_WAKELOCKS */
320 
pm_sleep_disable_secondary_cpus(void)321 static inline int pm_sleep_disable_secondary_cpus(void)
322 {
323 	cpuidle_pause();
324 	return suspend_disable_secondary_cpus();
325 }
326 
pm_sleep_enable_secondary_cpus(void)327 static inline void pm_sleep_enable_secondary_cpus(void)
328 {
329 	suspend_enable_secondary_cpus();
330 	cpuidle_resume();
331 }
332