xref: /linux/kernel/power/power.h (revision 757dea93e136b219af09d3cd56a81063fdbdef1a)
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 /*
18  * Keep some memory free so that I/O operations can succeed without paging
19  * [Might this be more than 4 MB?]
20  */
21 #define PAGES_FOR_IO	((4096 * 1024) >> PAGE_SHIFT)
22 /*
23  * Keep 1 MB of memory free so that device drivers can allocate some pages in
24  * their .suspend() routines without breaking the suspend to disk.
25  */
26 #define SPARE_PAGES	((1024 * 1024) >> PAGE_SHIFT)
27 
28 extern int pm_suspend_disk(void);
29 #else
30 static inline int pm_suspend_disk(void)
31 {
32 	return -EPERM;
33 }
34 #endif
35 
36 extern int pfn_is_nosave(unsigned long);
37 
38 extern struct mutex pm_mutex;
39 
40 #define power_attr(_name) \
41 static struct subsys_attribute _name##_attr = {	\
42 	.attr	= {				\
43 		.name = __stringify(_name),	\
44 		.mode = 0644,			\
45 	},					\
46 	.show	= _name##_show,			\
47 	.store	= _name##_store,		\
48 }
49 
50 extern struct kset power_subsys;
51 
52 /* Preferred image size in bytes (default 500 MB) */
53 extern unsigned long image_size;
54 extern int in_suspend;
55 extern dev_t swsusp_resume_device;
56 extern sector_t swsusp_resume_block;
57 
58 extern asmlinkage int swsusp_arch_suspend(void);
59 extern asmlinkage int swsusp_arch_resume(void);
60 
61 extern int create_basic_memory_bitmaps(void);
62 extern void free_basic_memory_bitmaps(void);
63 extern unsigned int count_data_pages(void);
64 
65 /**
66  *	Auxiliary structure used for reading the snapshot image data and
67  *	metadata from and writing them to the list of page backup entries
68  *	(PBEs) which is the main data structure of swsusp.
69  *
70  *	Using struct snapshot_handle we can transfer the image, including its
71  *	metadata, as a continuous sequence of bytes with the help of
72  *	snapshot_read_next() and snapshot_write_next().
73  *
74  *	The code that writes the image to a storage or transfers it to
75  *	the user land is required to use snapshot_read_next() for this
76  *	purpose and it should not make any assumptions regarding the internal
77  *	structure of the image.  Similarly, the code that reads the image from
78  *	a storage or transfers it from the user land is required to use
79  *	snapshot_write_next().
80  *
81  *	This may allow us to change the internal structure of the image
82  *	in the future with considerably less effort.
83  */
84 
85 struct snapshot_handle {
86 	loff_t		offset;	/* number of the last byte ready for reading
87 				 * or writing in the sequence
88 				 */
89 	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
90 				 * next operation will refer to (ie. current)
91 				 */
92 	unsigned int	cur_offset;	/* offset with respect to the current
93 					 * block (for the next operation)
94 					 */
95 	unsigned int	prev;	/* number of the block of PAGE_SIZE bytes that
96 				 * was the current one previously
97 				 */
98 	void		*buffer;	/* address of the block to read from
99 					 * or write to
100 					 */
101 	unsigned int	buf_offset;	/* location to read from or write to,
102 					 * given as a displacement from 'buffer'
103 					 */
104 	int		sync_read;	/* Set to one to notify the caller of
105 					 * snapshot_write_next() that it may
106 					 * need to call wait_on_bio_chain()
107 					 */
108 };
109 
110 /* This macro returns the address from/to which the caller of
111  * snapshot_read_next()/snapshot_write_next() is allowed to
112  * read/write data after the function returns
113  */
114 #define data_of(handle)	((handle).buffer + (handle).buf_offset)
115 
116 extern unsigned int snapshot_additional_pages(struct zone *zone);
117 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
118 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
119 extern void snapshot_write_finalize(struct snapshot_handle *handle);
120 extern int snapshot_image_loaded(struct snapshot_handle *handle);
121 
122 /*
123  * This structure is used to pass the values needed for the identification
124  * of the resume swap area from a user space to the kernel via the
125  * SNAPSHOT_SET_SWAP_AREA ioctl
126  */
127 struct resume_swap_area {
128 	loff_t offset;
129 	u_int32_t dev;
130 } __attribute__((packed));
131 
132 #define SNAPSHOT_IOC_MAGIC	'3'
133 #define SNAPSHOT_FREEZE			_IO(SNAPSHOT_IOC_MAGIC, 1)
134 #define SNAPSHOT_UNFREEZE		_IO(SNAPSHOT_IOC_MAGIC, 2)
135 #define SNAPSHOT_ATOMIC_SNAPSHOT	_IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
136 #define SNAPSHOT_ATOMIC_RESTORE		_IO(SNAPSHOT_IOC_MAGIC, 4)
137 #define SNAPSHOT_FREE			_IO(SNAPSHOT_IOC_MAGIC, 5)
138 #define SNAPSHOT_SET_IMAGE_SIZE		_IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
139 #define SNAPSHOT_AVAIL_SWAP		_IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
140 #define SNAPSHOT_GET_SWAP_PAGE		_IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
141 #define SNAPSHOT_FREE_SWAP_PAGES	_IO(SNAPSHOT_IOC_MAGIC, 9)
142 #define SNAPSHOT_SET_SWAP_FILE		_IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
143 #define SNAPSHOT_S2RAM			_IO(SNAPSHOT_IOC_MAGIC, 11)
144 #define SNAPSHOT_PMOPS			_IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
145 #define SNAPSHOT_SET_SWAP_AREA		_IOW(SNAPSHOT_IOC_MAGIC, 13, \
146 							struct resume_swap_area)
147 #define SNAPSHOT_IOC_MAXNR	13
148 
149 #define PMOPS_PREPARE	1
150 #define PMOPS_ENTER	2
151 #define PMOPS_FINISH	3
152 
153 /* If unset, the snapshot device cannot be open. */
154 extern atomic_t snapshot_device_available;
155 
156 extern sector_t alloc_swapdev_block(int swap);
157 extern void free_all_swap_pages(int swap);
158 extern int swsusp_swap_in_use(void);
159 
160 extern int swsusp_check(void);
161 extern int swsusp_shrink_memory(void);
162 extern void swsusp_free(void);
163 extern int swsusp_suspend(void);
164 extern int swsusp_resume(void);
165 extern int swsusp_read(void);
166 extern int swsusp_write(void);
167 extern void swsusp_close(void);
168 extern int suspend_enter(suspend_state_t state);
169 
170 struct timeval;
171 extern void swsusp_show_speed(struct timeval *, struct timeval *,
172 				unsigned int, char *);
173