xref: /linux/kernel/power/power.h (revision 7f3edee81fbd49114c28057512906f169caa0bed)
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 #ifdef CONFIG_HIBERNATION
15 #ifdef CONFIG_ARCH_HIBERNATION_HEADER
16 /* Maximum size of architecture specific data in a hibernation header */
17 #define MAX_ARCH_HEADER_SIZE	(sizeof(struct new_utsname) + 4)
18 
19 extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
20 extern int arch_hibernation_header_restore(void *addr);
21 
22 static inline int init_header_complete(struct swsusp_info *info)
23 {
24 	return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
25 }
26 
27 static inline char *check_image_kernel(struct swsusp_info *info)
28 {
29 	return arch_hibernation_header_restore(info) ?
30 			"architecture specific data" : NULL;
31 }
32 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
33 
34 /*
35  * Keep some memory free so that I/O operations can succeed without paging
36  * [Might this be more than 4 MB?]
37  */
38 #define PAGES_FOR_IO	((4096 * 1024) >> PAGE_SHIFT)
39 
40 /*
41  * Keep 1 MB of memory free so that device drivers can allocate some pages in
42  * their .suspend() routines without breaking the suspend to disk.
43  */
44 #define SPARE_PAGES	((1024 * 1024) >> PAGE_SHIFT)
45 
46 /* kernel/power/disk.c */
47 extern int hibernation_snapshot(int platform_mode);
48 extern int hibernation_restore(int platform_mode);
49 extern int hibernation_platform_enter(void);
50 #endif
51 
52 extern int pfn_is_nosave(unsigned long);
53 
54 extern struct mutex pm_mutex;
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 unsigned int count_data_pages(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 int snapshot_read_next(struct snapshot_handle *handle, size_t count);
132 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
133 extern void snapshot_write_finalize(struct snapshot_handle *handle);
134 extern int snapshot_image_loaded(struct snapshot_handle *handle);
135 
136 /*
137  * This structure is used to pass the values needed for the identification
138  * of the resume swap area from a user space to the kernel via the
139  * SNAPSHOT_SET_SWAP_AREA ioctl
140  */
141 struct resume_swap_area {
142 	loff_t offset;
143 	u_int32_t dev;
144 } __attribute__((packed));
145 
146 #define SNAPSHOT_IOC_MAGIC	'3'
147 #define SNAPSHOT_FREEZE			_IO(SNAPSHOT_IOC_MAGIC, 1)
148 #define SNAPSHOT_UNFREEZE		_IO(SNAPSHOT_IOC_MAGIC, 2)
149 #define SNAPSHOT_ATOMIC_SNAPSHOT	_IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
150 #define SNAPSHOT_ATOMIC_RESTORE		_IO(SNAPSHOT_IOC_MAGIC, 4)
151 #define SNAPSHOT_FREE			_IO(SNAPSHOT_IOC_MAGIC, 5)
152 #define SNAPSHOT_SET_IMAGE_SIZE		_IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
153 #define SNAPSHOT_AVAIL_SWAP		_IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
154 #define SNAPSHOT_GET_SWAP_PAGE		_IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
155 #define SNAPSHOT_FREE_SWAP_PAGES	_IO(SNAPSHOT_IOC_MAGIC, 9)
156 #define SNAPSHOT_SET_SWAP_FILE		_IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
157 #define SNAPSHOT_S2RAM			_IO(SNAPSHOT_IOC_MAGIC, 11)
158 #define SNAPSHOT_PMOPS			_IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
159 #define SNAPSHOT_SET_SWAP_AREA		_IOW(SNAPSHOT_IOC_MAGIC, 13, \
160 							struct resume_swap_area)
161 #define SNAPSHOT_IOC_MAXNR	13
162 
163 #define PMOPS_PREPARE	1
164 #define PMOPS_ENTER	2
165 #define PMOPS_FINISH	3
166 
167 /* If unset, the snapshot device cannot be open. */
168 extern atomic_t snapshot_device_available;
169 
170 extern sector_t alloc_swapdev_block(int swap);
171 extern void free_all_swap_pages(int swap);
172 extern int swsusp_swap_in_use(void);
173 
174 /*
175  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
176  * the image header.
177  */
178 #define SF_PLATFORM_MODE	1
179 
180 /* kernel/power/disk.c */
181 extern int swsusp_check(void);
182 extern int swsusp_shrink_memory(void);
183 extern void swsusp_free(void);
184 extern int swsusp_resume(void);
185 extern int swsusp_read(unsigned int *flags_p);
186 extern int swsusp_write(unsigned int flags);
187 extern void swsusp_close(void);
188 
189 struct timeval;
190 /* kernel/power/swsusp.c */
191 extern void swsusp_show_speed(struct timeval *, struct timeval *,
192 				unsigned int, char *);
193 
194 #ifdef CONFIG_SUSPEND
195 /* kernel/power/main.c */
196 extern int suspend_devices_and_enter(suspend_state_t state);
197 #else /* !CONFIG_SUSPEND */
198 static inline int suspend_devices_and_enter(suspend_state_t state)
199 {
200 	return -ENOSYS;
201 }
202 #endif /* !CONFIG_SUSPEND */
203 
204 /* kernel/power/common.c */
205 extern struct blocking_notifier_head pm_chain_head;
206 
207 static inline int pm_notifier_call_chain(unsigned long val)
208 {
209 	return (blocking_notifier_call_chain(&pm_chain_head, val, NULL)
210 			== NOTIFY_BAD) ? -EINVAL : 0;
211 }
212