xref: /linux/kernel/power/power.h (revision 98366c20a275e957416e9516db5dcb7195b4e101)
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 subsys_attribute _name##_attr = {	\
58 	.attr	= {				\
59 		.name = __stringify(_name),	\
60 		.mode = 0644,			\
61 	},					\
62 	.show	= _name##_show,			\
63 	.store	= _name##_store,		\
64 }
65 
66 extern struct kset power_subsys;
67 
68 /* Preferred image size in bytes (default 500 MB) */
69 extern unsigned long image_size;
70 extern int in_suspend;
71 extern dev_t swsusp_resume_device;
72 extern sector_t swsusp_resume_block;
73 
74 extern asmlinkage int swsusp_arch_suspend(void);
75 extern asmlinkage int swsusp_arch_resume(void);
76 
77 extern int create_basic_memory_bitmaps(void);
78 extern void free_basic_memory_bitmaps(void);
79 extern unsigned int count_data_pages(void);
80 
81 /**
82  *	Auxiliary structure used for reading the snapshot image data and
83  *	metadata from and writing them to the list of page backup entries
84  *	(PBEs) which is the main data structure of swsusp.
85  *
86  *	Using struct snapshot_handle we can transfer the image, including its
87  *	metadata, as a continuous sequence of bytes with the help of
88  *	snapshot_read_next() and snapshot_write_next().
89  *
90  *	The code that writes the image to a storage or transfers it to
91  *	the user land is required to use snapshot_read_next() for this
92  *	purpose and it should not make any assumptions regarding the internal
93  *	structure of the image.  Similarly, the code that reads the image from
94  *	a storage or transfers it from the user land is required to use
95  *	snapshot_write_next().
96  *
97  *	This may allow us to change the internal structure of the image
98  *	in the future with considerably less effort.
99  */
100 
101 struct snapshot_handle {
102 	loff_t		offset;	/* number of the last byte ready for reading
103 				 * or writing in the sequence
104 				 */
105 	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
106 				 * next operation will refer to (ie. current)
107 				 */
108 	unsigned int	cur_offset;	/* offset with respect to the current
109 					 * block (for the next operation)
110 					 */
111 	unsigned int	prev;	/* number of the block of PAGE_SIZE bytes that
112 				 * was the current one previously
113 				 */
114 	void		*buffer;	/* address of the block to read from
115 					 * or write to
116 					 */
117 	unsigned int	buf_offset;	/* location to read from or write to,
118 					 * given as a displacement from 'buffer'
119 					 */
120 	int		sync_read;	/* Set to one to notify the caller of
121 					 * snapshot_write_next() that it may
122 					 * need to call wait_on_bio_chain()
123 					 */
124 };
125 
126 /* This macro returns the address from/to which the caller of
127  * snapshot_read_next()/snapshot_write_next() is allowed to
128  * read/write data after the function returns
129  */
130 #define data_of(handle)	((handle).buffer + (handle).buf_offset)
131 
132 extern unsigned int snapshot_additional_pages(struct zone *zone);
133 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
134 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
135 extern void snapshot_write_finalize(struct snapshot_handle *handle);
136 extern int snapshot_image_loaded(struct snapshot_handle *handle);
137 
138 /*
139  * This structure is used to pass the values needed for the identification
140  * of the resume swap area from a user space to the kernel via the
141  * SNAPSHOT_SET_SWAP_AREA ioctl
142  */
143 struct resume_swap_area {
144 	loff_t offset;
145 	u_int32_t dev;
146 } __attribute__((packed));
147 
148 #define SNAPSHOT_IOC_MAGIC	'3'
149 #define SNAPSHOT_FREEZE			_IO(SNAPSHOT_IOC_MAGIC, 1)
150 #define SNAPSHOT_UNFREEZE		_IO(SNAPSHOT_IOC_MAGIC, 2)
151 #define SNAPSHOT_ATOMIC_SNAPSHOT	_IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
152 #define SNAPSHOT_ATOMIC_RESTORE		_IO(SNAPSHOT_IOC_MAGIC, 4)
153 #define SNAPSHOT_FREE			_IO(SNAPSHOT_IOC_MAGIC, 5)
154 #define SNAPSHOT_SET_IMAGE_SIZE		_IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
155 #define SNAPSHOT_AVAIL_SWAP		_IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
156 #define SNAPSHOT_GET_SWAP_PAGE		_IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
157 #define SNAPSHOT_FREE_SWAP_PAGES	_IO(SNAPSHOT_IOC_MAGIC, 9)
158 #define SNAPSHOT_SET_SWAP_FILE		_IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
159 #define SNAPSHOT_S2RAM			_IO(SNAPSHOT_IOC_MAGIC, 11)
160 #define SNAPSHOT_PMOPS			_IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
161 #define SNAPSHOT_SET_SWAP_AREA		_IOW(SNAPSHOT_IOC_MAGIC, 13, \
162 							struct resume_swap_area)
163 #define SNAPSHOT_IOC_MAXNR	13
164 
165 #define PMOPS_PREPARE	1
166 #define PMOPS_ENTER	2
167 #define PMOPS_FINISH	3
168 
169 /* If unset, the snapshot device cannot be open. */
170 extern atomic_t snapshot_device_available;
171 
172 extern sector_t alloc_swapdev_block(int swap);
173 extern void free_all_swap_pages(int swap);
174 extern int swsusp_swap_in_use(void);
175 
176 /*
177  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
178  * the image header.
179  */
180 #define SF_PLATFORM_MODE	1
181 
182 /* kernel/power/disk.c */
183 extern int swsusp_check(void);
184 extern int swsusp_shrink_memory(void);
185 extern void swsusp_free(void);
186 extern int swsusp_resume(void);
187 extern int swsusp_read(unsigned int *flags_p);
188 extern int swsusp_write(unsigned int flags);
189 extern void swsusp_close(void);
190 
191 struct timeval;
192 /* kernel/power/swsusp.c */
193 extern void swsusp_show_speed(struct timeval *, struct timeval *,
194 				unsigned int, char *);
195 
196 #ifdef CONFIG_SUSPEND
197 /* kernel/power/main.c */
198 extern int suspend_devices_and_enter(suspend_state_t state);
199 #else /* !CONFIG_SUSPEND */
200 static inline int suspend_devices_and_enter(suspend_state_t state)
201 {
202 	return -ENOSYS;
203 }
204 #endif /* !CONFIG_SUSPEND */
205 
206 /* kernel/power/common.c */
207 extern struct blocking_notifier_head pm_chain_head;
208 
209 static inline int pm_notifier_call_chain(unsigned long val)
210 {
211 	return (blocking_notifier_call_chain(&pm_chain_head, val, NULL)
212 			== NOTIFY_BAD) ? -EINVAL : 0;
213 }
214