PM / Hibernate: Separate block_io
[linux-2.6.git] / kernel / power / power.h
1 #include <linux/suspend.h>
2 #include <linux/suspend_ioctls.h>
3 #include <linux/utsname.h>
4 #include <linux/freezer.h>
5
6 struct swsusp_info {
7         struct new_utsname      uts;
8         u32                     version_code;
9         unsigned long           num_physpages;
10         int                     cpus;
11         unsigned long           image_pages;
12         unsigned long           pages;
13         unsigned long           size;
14 } __attribute__((aligned(PAGE_SIZE)));
15
16 #ifdef CONFIG_HIBERNATION
17 #ifdef CONFIG_ARCH_HIBERNATION_HEADER
18 /* Maximum size of architecture specific data in a hibernation header */
19 #define MAX_ARCH_HEADER_SIZE    (sizeof(struct new_utsname) + 4)
20
21 extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
22 extern int arch_hibernation_header_restore(void *addr);
23
24 static inline int init_header_complete(struct swsusp_info *info)
25 {
26         return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
27 }
28
29 static inline char *check_image_kernel(struct swsusp_info *info)
30 {
31         return arch_hibernation_header_restore(info) ?
32                         "architecture specific data" : NULL;
33 }
34 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
35
36 /*
37  * Keep some memory free so that I/O operations can succeed without paging
38  * [Might this be more than 4 MB?]
39  */
40 #define PAGES_FOR_IO    ((4096 * 1024) >> PAGE_SHIFT)
41
42 /*
43  * Keep 1 MB of memory free so that device drivers can allocate some pages in
44  * their .suspend() routines without breaking the suspend to disk.
45  */
46 #define SPARE_PAGES     ((1024 * 1024) >> PAGE_SHIFT)
47
48 /* kernel/power/hibernate.c */
49 extern int hibernation_snapshot(int platform_mode);
50 extern int hibernation_restore(int platform_mode);
51 extern int hibernation_platform_enter(void);
52 #endif
53
54 extern int pfn_is_nosave(unsigned long);
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 int hibernate_preallocate_memory(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         unsigned int    cur;    /* number of the block of PAGE_SIZE bytes the
101                                  * next operation will refer to (ie. current)
102                                  */
103         void            *buffer;        /* address of the block to read from
104                                          * or write to
105                                          */
106         int             sync_read;      /* Set to one to notify the caller of
107                                          * snapshot_write_next() that it may
108                                          * need to call wait_on_bio_chain()
109                                          */
110 };
111
112 /* This macro returns the address from/to which the caller of
113  * snapshot_read_next()/snapshot_write_next() is allowed to
114  * read/write data after the function returns
115  */
116 #define data_of(handle) ((handle).buffer)
117
118 extern unsigned int snapshot_additional_pages(struct zone *zone);
119 extern unsigned long snapshot_get_image_size(void);
120 extern int snapshot_read_next(struct snapshot_handle *handle);
121 extern int snapshot_write_next(struct snapshot_handle *handle);
122 extern void snapshot_write_finalize(struct snapshot_handle *handle);
123 extern int snapshot_image_loaded(struct snapshot_handle *handle);
124
125 /* If unset, the snapshot device cannot be open. */
126 extern atomic_t snapshot_device_available;
127
128 extern sector_t alloc_swapdev_block(int swap);
129 extern void free_all_swap_pages(int swap);
130 extern int swsusp_swap_in_use(void);
131
132 /*
133  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
134  * the image header.
135  */
136 #define SF_PLATFORM_MODE        1
137
138 /* kernel/power/hibernate.c */
139 extern int swsusp_check(void);
140 extern void swsusp_free(void);
141 extern int swsusp_read(unsigned int *flags_p);
142 extern int swsusp_write(unsigned int flags);
143 extern void swsusp_close(fmode_t);
144
145 /* kernel/power/block_io.c */
146 extern struct block_device *hib_resume_bdev;
147
148 extern int hib_bio_read_page(pgoff_t page_off, void *addr,
149                 struct bio **bio_chain);
150 extern int hib_bio_write_page(pgoff_t page_off, void *addr,
151                 struct bio **bio_chain);
152 extern int hib_wait_on_bio_chain(struct bio **bio_chain);
153
154 struct timeval;
155 /* kernel/power/swsusp.c */
156 extern void swsusp_show_speed(struct timeval *, struct timeval *,
157                                 unsigned int, char *);
158
159 #ifdef CONFIG_SUSPEND
160 /* kernel/power/suspend.c */
161 extern const char *const pm_states[];
162
163 extern bool valid_state(suspend_state_t state);
164 extern int suspend_devices_and_enter(suspend_state_t state);
165 extern int enter_state(suspend_state_t state);
166 #else /* !CONFIG_SUSPEND */
167 static inline int suspend_devices_and_enter(suspend_state_t state)
168 {
169         return -ENOSYS;
170 }
171 static inline int enter_state(suspend_state_t state) { return -ENOSYS; }
172 static inline bool valid_state(suspend_state_t state) { return false; }
173 #endif /* !CONFIG_SUSPEND */
174
175 #ifdef CONFIG_PM_TEST_SUSPEND
176 /* kernel/power/suspend_test.c */
177 extern void suspend_test_start(void);
178 extern void suspend_test_finish(const char *label);
179 #else /* !CONFIG_PM_TEST_SUSPEND */
180 static inline void suspend_test_start(void) {}
181 static inline void suspend_test_finish(const char *label) {}
182 #endif /* !CONFIG_PM_TEST_SUSPEND */
183
184 #ifdef CONFIG_PM_SLEEP
185 /* kernel/power/main.c */
186 extern int pm_notifier_call_chain(unsigned long val);
187 #endif
188
189 #ifdef CONFIG_HIGHMEM
190 int restore_highmem(void);
191 #else
192 static inline unsigned int count_highmem_pages(void) { return 0; }
193 static inline int restore_highmem(void) { return 0; }
194 #endif
195
196 /*
197  * Suspend test levels
198  */
199 enum {
200         /* keep first */
201         TEST_NONE,
202         TEST_CORE,
203         TEST_CPUS,
204         TEST_PLATFORM,
205         TEST_DEVICES,
206         TEST_FREEZER,
207         /* keep last */
208         __TEST_AFTER_LAST
209 };
210
211 #define TEST_FIRST      TEST_NONE
212 #define TEST_MAX        (__TEST_AFTER_LAST - 1)
213
214 extern int pm_test_level;
215
216 #ifdef CONFIG_SUSPEND_FREEZER
217 static inline int suspend_freeze_processes(void)
218 {
219         return freeze_processes();
220 }
221
222 static inline void suspend_thaw_processes(void)
223 {
224         thaw_processes();
225 }
226 #else
227 static inline int suspend_freeze_processes(void)
228 {
229         return 0;
230 }
231
232 static inline void suspend_thaw_processes(void)
233 {
234 }
235 #endif