xref: /openbmc/linux/kernel/power/power.h (revision 4bdf0bb7)
1 #include <linux/suspend.h>
2 #include <linux/suspend_ioctls.h>
3 #include <linux/utsname.h>
4 #include <linux/freezer.h>
5 
6 struct swsusp_info {
7 	struct new_utsname	uts;
8 	u32			version_code;
9 	unsigned long		num_physpages;
10 	int			cpus;
11 	unsigned long		image_pages;
12 	unsigned long		pages;
13 	unsigned long		size;
14 } __attribute__((aligned(PAGE_SIZE)));
15 
16 #ifdef CONFIG_HIBERNATION
17 #ifdef CONFIG_ARCH_HIBERNATION_HEADER
18 /* Maximum size of architecture specific data in a hibernation header */
19 #define MAX_ARCH_HEADER_SIZE	(sizeof(struct new_utsname) + 4)
20 
21 extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
22 extern int arch_hibernation_header_restore(void *addr);
23 
24 static inline int init_header_complete(struct swsusp_info *info)
25 {
26 	return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
27 }
28 
29 static inline char *check_image_kernel(struct swsusp_info *info)
30 {
31 	return arch_hibernation_header_restore(info) ?
32 			"architecture specific data" : NULL;
33 }
34 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
35 
36 /*
37  * Keep some memory free so that I/O operations can succeed without paging
38  * [Might this be more than 4 MB?]
39  */
40 #define PAGES_FOR_IO	((4096 * 1024) >> PAGE_SHIFT)
41 
42 /*
43  * Keep 1 MB of memory free so that device drivers can allocate some pages in
44  * their .suspend() routines without breaking the suspend to disk.
45  */
46 #define SPARE_PAGES	((1024 * 1024) >> PAGE_SHIFT)
47 
48 /* kernel/power/hibernate.c */
49 extern int hibernation_snapshot(int platform_mode);
50 extern int hibernation_restore(int platform_mode);
51 extern int hibernation_platform_enter(void);
52 #endif
53 
54 extern int pfn_is_nosave(unsigned long);
55 
56 #define power_attr(_name) \
57 static struct kobj_attribute _name##_attr = {	\
58 	.attr	= {				\
59 		.name = __stringify(_name),	\
60 		.mode = 0644,			\
61 	},					\
62 	.show	= _name##_show,			\
63 	.store	= _name##_store,		\
64 }
65 
66 /* Preferred image size in bytes (default 500 MB) */
67 extern unsigned long image_size;
68 extern int in_suspend;
69 extern dev_t swsusp_resume_device;
70 extern sector_t swsusp_resume_block;
71 
72 extern asmlinkage int swsusp_arch_suspend(void);
73 extern asmlinkage int swsusp_arch_resume(void);
74 
75 extern int create_basic_memory_bitmaps(void);
76 extern void free_basic_memory_bitmaps(void);
77 extern int hibernate_preallocate_memory(void);
78 
79 /**
80  *	Auxiliary structure used for reading the snapshot image data and
81  *	metadata from and writing them to the list of page backup entries
82  *	(PBEs) which is the main data structure of swsusp.
83  *
84  *	Using struct snapshot_handle we can transfer the image, including its
85  *	metadata, as a continuous sequence of bytes with the help of
86  *	snapshot_read_next() and snapshot_write_next().
87  *
88  *	The code that writes the image to a storage or transfers it to
89  *	the user land is required to use snapshot_read_next() for this
90  *	purpose and it should not make any assumptions regarding the internal
91  *	structure of the image.  Similarly, the code that reads the image from
92  *	a storage or transfers it from the user land is required to use
93  *	snapshot_write_next().
94  *
95  *	This may allow us to change the internal structure of the image
96  *	in the future with considerably less effort.
97  */
98 
99 struct snapshot_handle {
100 	loff_t		offset;	/* number of the last byte ready for reading
101 				 * or writing in the sequence
102 				 */
103 	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
104 				 * next operation will refer to (ie. current)
105 				 */
106 	unsigned int	cur_offset;	/* offset with respect to the current
107 					 * block (for the next operation)
108 					 */
109 	unsigned int	prev;	/* number of the block of PAGE_SIZE bytes that
110 				 * was the current one previously
111 				 */
112 	void		*buffer;	/* address of the block to read from
113 					 * or write to
114 					 */
115 	unsigned int	buf_offset;	/* location to read from or write to,
116 					 * given as a displacement from 'buffer'
117 					 */
118 	int		sync_read;	/* Set to one to notify the caller of
119 					 * snapshot_write_next() that it may
120 					 * need to call wait_on_bio_chain()
121 					 */
122 };
123 
124 /* This macro returns the address from/to which the caller of
125  * snapshot_read_next()/snapshot_write_next() is allowed to
126  * read/write data after the function returns
127  */
128 #define data_of(handle)	((handle).buffer + (handle).buf_offset)
129 
130 extern unsigned int snapshot_additional_pages(struct zone *zone);
131 extern unsigned long snapshot_get_image_size(void);
132 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
133 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
134 extern void snapshot_write_finalize(struct snapshot_handle *handle);
135 extern int snapshot_image_loaded(struct snapshot_handle *handle);
136 
137 /* If unset, the snapshot device cannot be open. */
138 extern atomic_t snapshot_device_available;
139 
140 extern sector_t alloc_swapdev_block(int swap);
141 extern void free_all_swap_pages(int swap);
142 extern int swsusp_swap_in_use(void);
143 
144 /*
145  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
146  * the image header.
147  */
148 #define SF_PLATFORM_MODE	1
149 
150 /* kernel/power/hibernate.c */
151 extern int swsusp_check(void);
152 extern void swsusp_free(void);
153 extern int swsusp_read(unsigned int *flags_p);
154 extern int swsusp_write(unsigned int flags);
155 extern void swsusp_close(fmode_t);
156 
157 struct timeval;
158 /* kernel/power/swsusp.c */
159 extern void swsusp_show_speed(struct timeval *, struct timeval *,
160 				unsigned int, char *);
161 
162 #ifdef CONFIG_SUSPEND
163 /* kernel/power/suspend.c */
164 extern const char *const pm_states[];
165 
166 extern bool valid_state(suspend_state_t state);
167 extern int suspend_devices_and_enter(suspend_state_t state);
168 extern int enter_state(suspend_state_t state);
169 #else /* !CONFIG_SUSPEND */
170 static inline int suspend_devices_and_enter(suspend_state_t state)
171 {
172 	return -ENOSYS;
173 }
174 static inline int enter_state(suspend_state_t state) { return -ENOSYS; }
175 static inline bool valid_state(suspend_state_t state) { return false; }
176 #endif /* !CONFIG_SUSPEND */
177 
178 #ifdef CONFIG_PM_TEST_SUSPEND
179 /* kernel/power/suspend_test.c */
180 extern void suspend_test_start(void);
181 extern void suspend_test_finish(const char *label);
182 #else /* !CONFIG_PM_TEST_SUSPEND */
183 static inline void suspend_test_start(void) {}
184 static inline void suspend_test_finish(const char *label) {}
185 #endif /* !CONFIG_PM_TEST_SUSPEND */
186 
187 #ifdef CONFIG_PM_SLEEP
188 /* kernel/power/main.c */
189 extern int pm_notifier_call_chain(unsigned long val);
190 #endif
191 
192 #ifdef CONFIG_HIGHMEM
193 int restore_highmem(void);
194 #else
195 static inline unsigned int count_highmem_pages(void) { return 0; }
196 static inline int restore_highmem(void) { return 0; }
197 #endif
198 
199 /*
200  * Suspend test levels
201  */
202 enum {
203 	/* keep first */
204 	TEST_NONE,
205 	TEST_CORE,
206 	TEST_CPUS,
207 	TEST_PLATFORM,
208 	TEST_DEVICES,
209 	TEST_FREEZER,
210 	/* keep last */
211 	__TEST_AFTER_LAST
212 };
213 
214 #define TEST_FIRST	TEST_NONE
215 #define TEST_MAX	(__TEST_AFTER_LAST - 1)
216 
217 extern int pm_test_level;
218 
219 #ifdef CONFIG_SUSPEND_FREEZER
220 static inline int suspend_freeze_processes(void)
221 {
222 	return freeze_processes();
223 }
224 
225 static inline void suspend_thaw_processes(void)
226 {
227 	thaw_processes();
228 }
229 #else
230 static inline int suspend_freeze_processes(void)
231 {
232 	return 0;
233 }
234 
235 static inline void suspend_thaw_processes(void)
236 {
237 }
238 #endif
239