xref: /openbmc/linux/kernel/power/power.h (revision 8684014d)
1 #include <linux/suspend.h>
2 #include <linux/suspend_ioctls.h>
3 #include <linux/utsname.h>
4 #include <linux/freezer.h>
5 #include <linux/compiler.h>
6 
7 struct swsusp_info {
8 	struct new_utsname	uts;
9 	u32			version_code;
10 	unsigned long		num_physpages;
11 	int			cpus;
12 	unsigned long		image_pages;
13 	unsigned long		pages;
14 	unsigned long		size;
15 } __aligned(PAGE_SIZE);
16 
17 #ifdef CONFIG_HIBERNATION
18 /* kernel/power/snapshot.c */
19 extern void __init hibernate_reserved_size_init(void);
20 extern void __init hibernate_image_size_init(void);
21 
22 #ifdef CONFIG_ARCH_HIBERNATION_HEADER
23 /* Maximum size of architecture specific data in a hibernation header */
24 #define MAX_ARCH_HEADER_SIZE	(sizeof(struct new_utsname) + 4)
25 
26 extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
27 extern int arch_hibernation_header_restore(void *addr);
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 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 #else /* !CONFIG_HIBERNATION */
63 
64 static inline void hibernate_reserved_size_init(void) {}
65 static inline void hibernate_image_size_init(void) {}
66 #endif /* !CONFIG_HIBERNATION */
67 
68 extern int pfn_is_nosave(unsigned long);
69 
70 #define power_attr(_name) \
71 static struct kobj_attribute _name##_attr = {	\
72 	.attr	= {				\
73 		.name = __stringify(_name),	\
74 		.mode = 0644,			\
75 	},					\
76 	.show	= _name##_show,			\
77 	.store	= _name##_store,		\
78 }
79 
80 /* Preferred image size in bytes (default 500 MB) */
81 extern unsigned long image_size;
82 /* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
83 extern unsigned long reserved_size;
84 extern int in_suspend;
85 extern dev_t swsusp_resume_device;
86 extern sector_t swsusp_resume_block;
87 
88 extern asmlinkage int swsusp_arch_suspend(void);
89 extern asmlinkage int swsusp_arch_resume(void);
90 
91 extern int create_basic_memory_bitmaps(void);
92 extern void free_basic_memory_bitmaps(void);
93 extern int hibernate_preallocate_memory(void);
94 
95 /**
96  *	Auxiliary structure used for reading the snapshot image data and
97  *	metadata from and writing them to the list of page backup entries
98  *	(PBEs) which is the main data structure of swsusp.
99  *
100  *	Using struct snapshot_handle we can transfer the image, including its
101  *	metadata, as a continuous sequence of bytes with the help of
102  *	snapshot_read_next() and snapshot_write_next().
103  *
104  *	The code that writes the image to a storage or transfers it to
105  *	the user land is required to use snapshot_read_next() for this
106  *	purpose and it should not make any assumptions regarding the internal
107  *	structure of the image.  Similarly, the code that reads the image from
108  *	a storage or transfers it from the user land is required to use
109  *	snapshot_write_next().
110  *
111  *	This may allow us to change the internal structure of the image
112  *	in the future with considerably less effort.
113  */
114 
115 struct snapshot_handle {
116 	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
117 				 * next operation will refer to (ie. current)
118 				 */
119 	void		*buffer;	/* address of the block to read from
120 					 * or write to
121 					 */
122 	int		sync_read;	/* Set to one to notify the caller of
123 					 * snapshot_write_next() that it may
124 					 * need to call wait_on_bio_chain()
125 					 */
126 };
127 
128 /* This macro returns the address from/to which the caller of
129  * snapshot_read_next()/snapshot_write_next() is allowed to
130  * read/write data after the function returns
131  */
132 #define data_of(handle)	((handle).buffer)
133 
134 extern unsigned int snapshot_additional_pages(struct zone *zone);
135 extern unsigned long snapshot_get_image_size(void);
136 extern int snapshot_read_next(struct snapshot_handle *handle);
137 extern int snapshot_write_next(struct snapshot_handle *handle);
138 extern void snapshot_write_finalize(struct snapshot_handle *handle);
139 extern int snapshot_image_loaded(struct snapshot_handle *handle);
140 
141 /* If unset, the snapshot device cannot be open. */
142 extern atomic_t snapshot_device_available;
143 
144 extern sector_t alloc_swapdev_block(int swap);
145 extern void free_all_swap_pages(int swap);
146 extern int swsusp_swap_in_use(void);
147 
148 /*
149  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
150  * the image header.
151  */
152 #define SF_PLATFORM_MODE	1
153 #define SF_NOCOMPRESS_MODE	2
154 #define SF_CRC32_MODE	        4
155 
156 /* kernel/power/hibernate.c */
157 extern int swsusp_check(void);
158 extern void swsusp_free(void);
159 extern int swsusp_read(unsigned int *flags_p);
160 extern int swsusp_write(unsigned int flags);
161 extern void swsusp_close(fmode_t);
162 #ifdef CONFIG_SUSPEND
163 extern int swsusp_unmark(void);
164 #endif
165 
166 /* kernel/power/block_io.c */
167 extern struct block_device *hib_resume_bdev;
168 
169 extern int hib_bio_read_page(pgoff_t page_off, void *addr,
170 		struct bio **bio_chain);
171 extern int hib_bio_write_page(pgoff_t page_off, void *addr,
172 		struct bio **bio_chain);
173 extern int hib_wait_on_bio_chain(struct bio **bio_chain);
174 
175 struct timeval;
176 /* kernel/power/swsusp.c */
177 extern void swsusp_show_speed(ktime_t, ktime_t, unsigned int, char *);
178 
179 #ifdef CONFIG_SUSPEND
180 /* kernel/power/suspend.c */
181 extern const char *pm_labels[];
182 extern const char *pm_states[];
183 
184 extern int suspend_devices_and_enter(suspend_state_t state);
185 #else /* !CONFIG_SUSPEND */
186 static inline int suspend_devices_and_enter(suspend_state_t state)
187 {
188 	return -ENOSYS;
189 }
190 #endif /* !CONFIG_SUSPEND */
191 
192 #ifdef CONFIG_PM_TEST_SUSPEND
193 /* kernel/power/suspend_test.c */
194 extern void suspend_test_start(void);
195 extern void suspend_test_finish(const char *label);
196 #else /* !CONFIG_PM_TEST_SUSPEND */
197 static inline void suspend_test_start(void) {}
198 static inline void suspend_test_finish(const char *label) {}
199 #endif /* !CONFIG_PM_TEST_SUSPEND */
200 
201 #ifdef CONFIG_PM_SLEEP
202 /* kernel/power/main.c */
203 extern int pm_notifier_call_chain(unsigned long val);
204 #endif
205 
206 #ifdef CONFIG_HIGHMEM
207 int restore_highmem(void);
208 #else
209 static inline unsigned int count_highmem_pages(void) { return 0; }
210 static inline int restore_highmem(void) { return 0; }
211 #endif
212 
213 /*
214  * Suspend test levels
215  */
216 enum {
217 	/* keep first */
218 	TEST_NONE,
219 	TEST_CORE,
220 	TEST_CPUS,
221 	TEST_PLATFORM,
222 	TEST_DEVICES,
223 	TEST_FREEZER,
224 	/* keep last */
225 	__TEST_AFTER_LAST
226 };
227 
228 #define TEST_FIRST	TEST_NONE
229 #define TEST_MAX	(__TEST_AFTER_LAST - 1)
230 
231 extern int pm_test_level;
232 
233 #ifdef CONFIG_SUSPEND_FREEZER
234 static inline int suspend_freeze_processes(void)
235 {
236 	int error;
237 
238 	error = freeze_processes();
239 	/*
240 	 * freeze_processes() automatically thaws every task if freezing
241 	 * fails. So we need not do anything extra upon error.
242 	 */
243 	if (error)
244 		return error;
245 
246 	error = freeze_kernel_threads();
247 	/*
248 	 * freeze_kernel_threads() thaws only kernel threads upon freezing
249 	 * failure. So we have to thaw the userspace tasks ourselves.
250 	 */
251 	if (error)
252 		thaw_processes();
253 
254 	return error;
255 }
256 
257 static inline void suspend_thaw_processes(void)
258 {
259 	thaw_processes();
260 }
261 #else
262 static inline int suspend_freeze_processes(void)
263 {
264 	return 0;
265 }
266 
267 static inline void suspend_thaw_processes(void)
268 {
269 }
270 #endif
271 
272 #ifdef CONFIG_PM_AUTOSLEEP
273 
274 /* kernel/power/autosleep.c */
275 extern int pm_autosleep_init(void);
276 extern int pm_autosleep_lock(void);
277 extern void pm_autosleep_unlock(void);
278 extern suspend_state_t pm_autosleep_state(void);
279 extern int pm_autosleep_set_state(suspend_state_t state);
280 
281 #else /* !CONFIG_PM_AUTOSLEEP */
282 
283 static inline int pm_autosleep_init(void) { return 0; }
284 static inline int pm_autosleep_lock(void) { return 0; }
285 static inline void pm_autosleep_unlock(void) {}
286 static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
287 
288 #endif /* !CONFIG_PM_AUTOSLEEP */
289 
290 #ifdef CONFIG_PM_WAKELOCKS
291 
292 /* kernel/power/wakelock.c */
293 extern ssize_t pm_show_wakelocks(char *buf, bool show_active);
294 extern int pm_wake_lock(const char *buf);
295 extern int pm_wake_unlock(const char *buf);
296 
297 #endif /* !CONFIG_PM_WAKELOCKS */
298