aboutsummaryrefslogtreecommitdiffstats
path: root/kernel/power/power.h
blob: 8ec5499c5ce180c0567919c5915b7d19eb21a597 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
#include <linux/suspend.h>
#include <linux/suspend_ioctls.h>
#include <linux/utsname.h>

struct swsusp_info {
	struct new_utsname	uts;
	u32			version_code;
	unsigned long		num_physpages;
	int			cpus;
	unsigned long		image_pages;
	unsigned long		pages;
	unsigned long		size;
} __attribute__((aligned(PAGE_SIZE)));

#ifdef CONFIG_HIBERNATION
#ifdef CONFIG_ARCH_HIBERNATION_HEADER
/* Maximum size of architecture specific data in a hibernation header */
#define MAX_ARCH_HEADER_SIZE	(sizeof(struct new_utsname) + 4)

extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
extern int arch_hibernation_header_restore(void *addr);

static inline int init_header_complete(struct swsusp_info *info)
{
	return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
}

static inline char *check_image_kernel(struct swsusp_info *info)
{
	return arch_hibernation_header_restore(info) ?
			"architecture specific data" : NULL;
}
#endif /* CONFIG_ARCH_HIBERNATION_HEADER */

/*
 * Keep some memory free so that I/O operations can succeed without paging
 * [Might this be more than 4 MB?]
 */
#define PAGES_FOR_IO	((4096 * 1024) >> PAGE_SHIFT)

/*
 * Keep 1 MB of memory free so that device drivers can allocate some pages in
 * their .suspend() routines without breaking the suspend to disk.
 */
#define SPARE_PAGES	((1024 * 1024) >> PAGE_SHIFT)

/* kernel/power/disk.c */
extern int hibernation_snapshot(int platform_mode);
extern int hibernation_restore(int platform_mode);
extern int hibernation_platform_enter(void);
#endif

extern int pfn_is_nosave(unsigned long);

extern struct mutex pm_mutex;

#define power_attr(_name) \
static struct kobj_attribute _name##_attr = {	\
	.attr	= {				\
		.name = __stringify(_name),	\
		.mode = 0644,			\
	},					\
	.show	= _name##_show,			\
	.store	= _name##_store,		\
}

/* Preferred image size in bytes (default 500 MB) */
extern unsigned long image_size;
extern int in_suspend;
extern dev_t swsusp_resume_device;
extern sector_t swsusp_resume_block;

extern asmlinkage int swsusp_arch_suspend(void);
extern asmlinkage int swsusp_arch_resume(void);

extern int create_basic_memory_bitmaps(void);
extern void free_basic_memory_bitmaps(void);
extern unsigned int count_data_pages(void);

/**
 *	Auxiliary structure used for reading the snapshot image data and
 *	metadata from and writing them to the list of page backup entries
 *	(PBEs) which is the main data structure of swsusp.
 *
 *	Using struct snapshot_handle we can transfer the image, including its
 *	metadata, as a continuous sequence of bytes with the help of
 *	snapshot_read_next() and snapshot_write_next().
 *
 *	The code that writes the image to a storage or transfers it to
 *	the user land is required to use snapshot_read_next() for this
 *	purpose and it should not make any assumptions regarding the internal
 *	structure of the image.  Similarly, the code that reads the image from
 *	a storage or transfers it from the user land is required to use
 *	snapshot_write_next().
 *
 *	This may allow us to change the internal structure of the image
 *	in the future with considerably less effort.
 */

struct snapshot_handle {
	loff_t		offset;	/* number of the last byte ready for reading
				 * or writing in the sequence
				 */
	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
				 * next operation will refer to (ie. current)
				 */
	unsigned int	cur_offset;	/* offset with respect to the current
					 * block (for the next operation)
					 */
	unsigned int	prev;	/* number of the block of PAGE_SIZE bytes that
				 * was the current one previously
				 */
	void		*buffer;	/* address of the block to read from
					 * or write to
					 */
	unsigned int	buf_offset;	/* location to read from or write to,
					 * given as a displacement from 'buffer'
					 */
	int		sync_read;	/* Set to one to notify the caller of
					 * snapshot_write_next() that it may
					 * need to call wait_on_bio_chain()
					 */
};

/* This macro returns the address from/to which the caller of
 * snapshot_read_next()/snapshot_write_next() is allowed to
 * read/write data after the function returns
 */
#define data_of(handle)	((handle).buffer + (handle).buf_offset)

extern unsigned int snapshot_additional_pages(struct zone *zone);
extern unsigned long snapshot_get_image_size(void);
extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
extern void snapshot_write_finalize(struct snapshot_handle *handle);
extern int snapshot_image_loaded(struct snapshot_handle *handle);

/* If unset, the snapshot device cannot be open. */
extern atomic_t snapshot_device_available;

extern sector_t alloc_swapdev_block(int swap);
extern void free_all_swap_pages(int swap);
extern int swsusp_swap_in_use(void);

/*
 * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
 * the image header.
 */
#define SF_PLATFORM_MODE	1

/* kernel/power/disk.c */
extern int swsusp_check(void);
extern int swsusp_shrink_memory(void);
extern void swsusp_free(void);
extern int swsusp_read(unsigned int *flags_p);
extern int swsusp_write(unsigned int flags);
extern void swsusp_close(void);

struct timeval;
/* kernel/power/swsusp.c */
extern void swsusp_show_speed(struct timeval *, struct timeval *,
				unsigned int, char *);

#ifdef CONFIG_SUSPEND
/* kernel/power/main.c */
extern int suspend_devices_and_enter(suspend_state_t state);
#else /* !CONFIG_SUSPEND */
static inline int suspend_devices_and_enter(suspend_state_t state)
{
	return -ENOSYS;
}
#endif /* !CONFIG_SUSPEND */

#ifdef CONFIG_PM_SLEEP
/* kernel/power/main.c */
extern int pm_notifier_call_chain(unsigned long val);
#endif

#ifdef CONFIG_HIGHMEM
unsigned int count_highmem_pages(void);
int restore_highmem(void);
#else
static inline unsigned int count_highmem_pages(void) { return 0; }
static inline int restore_highmem(void) { return 0; }
#endif

/*
 * Suspend test levels
 */
enum {
	/* keep first */
	TEST_NONE,
	TEST_CORE,
	TEST_CPUS,
	TEST_PLATFORM,
	TEST_DEVICES,
	TEST_FREEZER,
	/* keep last */
	__TEST_AFTER_LAST
};

#define TEST_FIRST	TEST_NONE
#define TEST_MAX	(__TEST_AFTER_LAST - 1)

extern int pm_test_level;