xref: /linux/kernel/power/power.h (revision c537b994505099b7197e7d3125b942ecbcc51eb6)
1 #include <linux/suspend.h>
2 #include <linux/utsname.h>
3 
4 struct swsusp_info {
5 	struct new_utsname	uts;
6 	u32			version_code;
7 	unsigned long		num_physpages;
8 	int			cpus;
9 	unsigned long		image_pages;
10 	unsigned long		pages;
11 	unsigned long		size;
12 } __attribute__((aligned(PAGE_SIZE)));
13 
14 
15 
16 #ifdef CONFIG_SOFTWARE_SUSPEND
17 extern int pm_suspend_disk(void);
18 
19 #else
20 static inline int pm_suspend_disk(void)
21 {
22 	return -EPERM;
23 }
24 #endif
25 
26 extern struct mutex pm_mutex;
27 
28 #define power_attr(_name) \
29 static struct subsys_attribute _name##_attr = {	\
30 	.attr	= {				\
31 		.name = __stringify(_name),	\
32 		.mode = 0644,			\
33 	},					\
34 	.show	= _name##_show,			\
35 	.store	= _name##_store,		\
36 }
37 
38 extern struct subsystem power_subsys;
39 
40 /* References to section boundaries */
41 extern const void __nosave_begin, __nosave_end;
42 
43 /* Preferred image size in bytes (default 500 MB) */
44 extern unsigned long image_size;
45 extern int in_suspend;
46 extern dev_t swsusp_resume_device;
47 extern sector_t swsusp_resume_block;
48 
49 extern asmlinkage int swsusp_arch_suspend(void);
50 extern asmlinkage int swsusp_arch_resume(void);
51 
52 extern unsigned int count_data_pages(void);
53 
54 /**
55  *	Auxiliary structure used for reading the snapshot image data and
56  *	metadata from and writing them to the list of page backup entries
57  *	(PBEs) which is the main data structure of swsusp.
58  *
59  *	Using struct snapshot_handle we can transfer the image, including its
60  *	metadata, as a continuous sequence of bytes with the help of
61  *	snapshot_read_next() and snapshot_write_next().
62  *
63  *	The code that writes the image to a storage or transfers it to
64  *	the user land is required to use snapshot_read_next() for this
65  *	purpose and it should not make any assumptions regarding the internal
66  *	structure of the image.  Similarly, the code that reads the image from
67  *	a storage or transfers it from the user land is required to use
68  *	snapshot_write_next().
69  *
70  *	This may allow us to change the internal structure of the image
71  *	in the future with considerably less effort.
72  */
73 
74 struct snapshot_handle {
75 	loff_t		offset;	/* number of the last byte ready for reading
76 				 * or writing in the sequence
77 				 */
78 	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
79 				 * next operation will refer to (ie. current)
80 				 */
81 	unsigned int	cur_offset;	/* offset with respect to the current
82 					 * block (for the next operation)
83 					 */
84 	unsigned int	prev;	/* number of the block of PAGE_SIZE bytes that
85 				 * was the current one previously
86 				 */
87 	void		*buffer;	/* address of the block to read from
88 					 * or write to
89 					 */
90 	unsigned int	buf_offset;	/* location to read from or write to,
91 					 * given as a displacement from 'buffer'
92 					 */
93 	int		sync_read;	/* Set to one to notify the caller of
94 					 * snapshot_write_next() that it may
95 					 * need to call wait_on_bio_chain()
96 					 */
97 };
98 
99 /* This macro returns the address from/to which the caller of
100  * snapshot_read_next()/snapshot_write_next() is allowed to
101  * read/write data after the function returns
102  */
103 #define data_of(handle)	((handle).buffer + (handle).buf_offset)
104 
105 extern unsigned int snapshot_additional_pages(struct zone *zone);
106 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
107 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
108 extern void snapshot_write_finalize(struct snapshot_handle *handle);
109 extern int snapshot_image_loaded(struct snapshot_handle *handle);
110 
111 /*
112  * This structure is used to pass the values needed for the identification
113  * of the resume swap area from a user space to the kernel via the
114  * SNAPSHOT_SET_SWAP_AREA ioctl
115  */
116 struct resume_swap_area {
117 	loff_t offset;
118 	u_int32_t dev;
119 } __attribute__((packed));
120 
121 #define SNAPSHOT_IOC_MAGIC	'3'
122 #define SNAPSHOT_FREEZE			_IO(SNAPSHOT_IOC_MAGIC, 1)
123 #define SNAPSHOT_UNFREEZE		_IO(SNAPSHOT_IOC_MAGIC, 2)
124 #define SNAPSHOT_ATOMIC_SNAPSHOT	_IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
125 #define SNAPSHOT_ATOMIC_RESTORE		_IO(SNAPSHOT_IOC_MAGIC, 4)
126 #define SNAPSHOT_FREE			_IO(SNAPSHOT_IOC_MAGIC, 5)
127 #define SNAPSHOT_SET_IMAGE_SIZE		_IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
128 #define SNAPSHOT_AVAIL_SWAP		_IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
129 #define SNAPSHOT_GET_SWAP_PAGE		_IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
130 #define SNAPSHOT_FREE_SWAP_PAGES	_IO(SNAPSHOT_IOC_MAGIC, 9)
131 #define SNAPSHOT_SET_SWAP_FILE		_IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
132 #define SNAPSHOT_S2RAM			_IO(SNAPSHOT_IOC_MAGIC, 11)
133 #define SNAPSHOT_PMOPS			_IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
134 #define SNAPSHOT_SET_SWAP_AREA		_IOW(SNAPSHOT_IOC_MAGIC, 13, \
135 							struct resume_swap_area)
136 #define SNAPSHOT_IOC_MAXNR	13
137 
138 #define PMOPS_PREPARE	1
139 #define PMOPS_ENTER	2
140 #define PMOPS_FINISH	3
141 
142 /**
143  *	The bitmap is used for tracing allocated swap pages
144  *
145  *	The entire bitmap consists of a number of bitmap_page
146  *	structures linked with the help of the .next member.
147  *	Thus each page can be allocated individually, so we only
148  *	need to make 0-order memory allocations to create
149  *	the bitmap.
150  */
151 
152 #define BITMAP_PAGE_SIZE	(PAGE_SIZE - sizeof(void *))
153 #define BITMAP_PAGE_CHUNKS	(BITMAP_PAGE_SIZE / sizeof(long))
154 #define BITS_PER_CHUNK		(sizeof(long) * 8)
155 #define BITMAP_PAGE_BITS	(BITMAP_PAGE_CHUNKS * BITS_PER_CHUNK)
156 
157 struct bitmap_page {
158 	unsigned long		chunks[BITMAP_PAGE_CHUNKS];
159 	struct bitmap_page	*next;
160 };
161 
162 extern void free_bitmap(struct bitmap_page *bitmap);
163 extern struct bitmap_page *alloc_bitmap(unsigned int nr_bits);
164 extern sector_t alloc_swapdev_block(int swap, struct bitmap_page *bitmap);
165 extern void free_all_swap_pages(int swap, struct bitmap_page *bitmap);
166 
167 extern int swsusp_check(void);
168 extern int swsusp_shrink_memory(void);
169 extern void swsusp_free(void);
170 extern int swsusp_suspend(void);
171 extern int swsusp_resume(void);
172 extern int swsusp_read(void);
173 extern int swsusp_write(void);
174 extern void swsusp_close(void);
175 extern int suspend_enter(suspend_state_t state);
176 
177 struct timeval;
178 extern void swsusp_show_speed(struct timeval *, struct timeval *,
179 				unsigned int, char *);
180