xref: /openbmc/linux/kernel/power/power.h (revision c21b37f6)
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_HIBERNATION
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 /* kernel/power/disk.c */
29 extern int hibernation_snapshot(int platform_mode);
30 extern int hibernation_restore(int platform_mode);
31 extern int hibernation_platform_enter(void);
32 #endif
33 
34 extern int pfn_is_nosave(unsigned long);
35 
36 extern struct mutex pm_mutex;
37 
38 #define power_attr(_name) \
39 static struct subsys_attribute _name##_attr = {	\
40 	.attr	= {				\
41 		.name = __stringify(_name),	\
42 		.mode = 0644,			\
43 	},					\
44 	.show	= _name##_show,			\
45 	.store	= _name##_store,		\
46 }
47 
48 extern struct kset power_subsys;
49 
50 /* Preferred image size in bytes (default 500 MB) */
51 extern unsigned long image_size;
52 extern int in_suspend;
53 extern dev_t swsusp_resume_device;
54 extern sector_t swsusp_resume_block;
55 
56 extern asmlinkage int swsusp_arch_suspend(void);
57 extern asmlinkage int swsusp_arch_resume(void);
58 
59 extern int create_basic_memory_bitmaps(void);
60 extern void free_basic_memory_bitmaps(void);
61 extern unsigned int count_data_pages(void);
62 
63 /**
64  *	Auxiliary structure used for reading the snapshot image data and
65  *	metadata from and writing them to the list of page backup entries
66  *	(PBEs) which is the main data structure of swsusp.
67  *
68  *	Using struct snapshot_handle we can transfer the image, including its
69  *	metadata, as a continuous sequence of bytes with the help of
70  *	snapshot_read_next() and snapshot_write_next().
71  *
72  *	The code that writes the image to a storage or transfers it to
73  *	the user land is required to use snapshot_read_next() for this
74  *	purpose and it should not make any assumptions regarding the internal
75  *	structure of the image.  Similarly, the code that reads the image from
76  *	a storage or transfers it from the user land is required to use
77  *	snapshot_write_next().
78  *
79  *	This may allow us to change the internal structure of the image
80  *	in the future with considerably less effort.
81  */
82 
83 struct snapshot_handle {
84 	loff_t		offset;	/* number of the last byte ready for reading
85 				 * or writing in the sequence
86 				 */
87 	unsigned int	cur;	/* number of the block of PAGE_SIZE bytes the
88 				 * next operation will refer to (ie. current)
89 				 */
90 	unsigned int	cur_offset;	/* offset with respect to the current
91 					 * block (for the next operation)
92 					 */
93 	unsigned int	prev;	/* number of the block of PAGE_SIZE bytes that
94 				 * was the current one previously
95 				 */
96 	void		*buffer;	/* address of the block to read from
97 					 * or write to
98 					 */
99 	unsigned int	buf_offset;	/* location to read from or write to,
100 					 * given as a displacement from 'buffer'
101 					 */
102 	int		sync_read;	/* Set to one to notify the caller of
103 					 * snapshot_write_next() that it may
104 					 * need to call wait_on_bio_chain()
105 					 */
106 };
107 
108 /* This macro returns the address from/to which the caller of
109  * snapshot_read_next()/snapshot_write_next() is allowed to
110  * read/write data after the function returns
111  */
112 #define data_of(handle)	((handle).buffer + (handle).buf_offset)
113 
114 extern unsigned int snapshot_additional_pages(struct zone *zone);
115 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
116 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
117 extern void snapshot_write_finalize(struct snapshot_handle *handle);
118 extern int snapshot_image_loaded(struct snapshot_handle *handle);
119 
120 /*
121  * This structure is used to pass the values needed for the identification
122  * of the resume swap area from a user space to the kernel via the
123  * SNAPSHOT_SET_SWAP_AREA ioctl
124  */
125 struct resume_swap_area {
126 	loff_t offset;
127 	u_int32_t dev;
128 } __attribute__((packed));
129 
130 #define SNAPSHOT_IOC_MAGIC	'3'
131 #define SNAPSHOT_FREEZE			_IO(SNAPSHOT_IOC_MAGIC, 1)
132 #define SNAPSHOT_UNFREEZE		_IO(SNAPSHOT_IOC_MAGIC, 2)
133 #define SNAPSHOT_ATOMIC_SNAPSHOT	_IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
134 #define SNAPSHOT_ATOMIC_RESTORE		_IO(SNAPSHOT_IOC_MAGIC, 4)
135 #define SNAPSHOT_FREE			_IO(SNAPSHOT_IOC_MAGIC, 5)
136 #define SNAPSHOT_SET_IMAGE_SIZE		_IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
137 #define SNAPSHOT_AVAIL_SWAP		_IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
138 #define SNAPSHOT_GET_SWAP_PAGE		_IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
139 #define SNAPSHOT_FREE_SWAP_PAGES	_IO(SNAPSHOT_IOC_MAGIC, 9)
140 #define SNAPSHOT_SET_SWAP_FILE		_IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
141 #define SNAPSHOT_S2RAM			_IO(SNAPSHOT_IOC_MAGIC, 11)
142 #define SNAPSHOT_PMOPS			_IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
143 #define SNAPSHOT_SET_SWAP_AREA		_IOW(SNAPSHOT_IOC_MAGIC, 13, \
144 							struct resume_swap_area)
145 #define SNAPSHOT_IOC_MAXNR	13
146 
147 #define PMOPS_PREPARE	1
148 #define PMOPS_ENTER	2
149 #define PMOPS_FINISH	3
150 
151 /* If unset, the snapshot device cannot be open. */
152 extern atomic_t snapshot_device_available;
153 
154 extern sector_t alloc_swapdev_block(int swap);
155 extern void free_all_swap_pages(int swap);
156 extern int swsusp_swap_in_use(void);
157 
158 /*
159  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
160  * the image header.
161  */
162 #define SF_PLATFORM_MODE	1
163 
164 /* kernel/power/disk.c */
165 extern int swsusp_check(void);
166 extern int swsusp_shrink_memory(void);
167 extern void swsusp_free(void);
168 extern int swsusp_suspend(void);
169 extern int swsusp_resume(void);
170 extern int swsusp_read(unsigned int *flags_p);
171 extern int swsusp_write(unsigned int flags);
172 extern void swsusp_close(void);
173 
174 struct timeval;
175 /* kernel/power/swsusp.c */
176 extern void swsusp_show_speed(struct timeval *, struct timeval *,
177 				unsigned int, char *);
178 
179 #ifdef CONFIG_SUSPEND
180 /* kernel/power/main.c */
181 extern int suspend_devices_and_enter(suspend_state_t state);
182 #else /* !CONFIG_SUSPEND */
183 static inline int suspend_devices_and_enter(suspend_state_t state)
184 {
185 	return -ENOSYS;
186 }
187 #endif /* !CONFIG_SUSPEND */
188 
189 /* kernel/power/common.c */
190 extern struct blocking_notifier_head pm_chain_head;
191 
192 static inline int pm_notifier_call_chain(unsigned long val)
193 {
194 	return (blocking_notifier_call_chain(&pm_chain_head, val, NULL)
195 			== NOTIFY_BAD) ? -EINVAL : 0;
196 }
197