writeback: split writeback_inodes_wb
[linux-2.6/next.git] / kernel / power / power.h
blob006270fe382d7f756e02082e4f5309258b1ca5e3
1 #include <linux/suspend.h>
2 #include <linux/suspend_ioctls.h>
3 #include <linux/utsname.h>
4 #include <linux/freezer.h>
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)));
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)
21 extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
22 extern int arch_hibernation_header_restore(void *addr);
24 static inline int init_header_complete(struct swsusp_info *info)
26 return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
29 static inline char *check_image_kernel(struct swsusp_info *info)
31 return arch_hibernation_header_restore(info) ?
32 "architecture specific data" : NULL;
34 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
37 * Keep some memory free so that I/O operations can succeed without paging
38 * [Might this be more than 4 MB?]
40 #define PAGES_FOR_IO ((4096 * 1024) >> PAGE_SHIFT)
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.
46 #define SPARE_PAGES ((1024 * 1024) >> PAGE_SHIFT)
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
54 extern int pfn_is_nosave(unsigned long);
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, \
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;
72 extern asmlinkage int swsusp_arch_suspend(void);
73 extern asmlinkage int swsusp_arch_resume(void);
75 extern int create_basic_memory_bitmaps(void);
76 extern void free_basic_memory_bitmaps(void);
77 extern int hibernate_preallocate_memory(void);
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.
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().
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().
95 * This may allow us to change the internal structure of the image
96 * in the future with considerably less effort.
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)
103 void *buffer; /* address of the block to read from
104 * or write to
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()
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
116 #define data_of(handle) ((handle).buffer)
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);
125 /* If unset, the snapshot device cannot be open. */
126 extern atomic_t snapshot_device_available;
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);
133 * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
134 * the image header.
136 #define SF_PLATFORM_MODE 1
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);
145 /* kernel/power/block_io.c */
146 extern struct block_device *hib_resume_bdev;
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);
154 struct timeval;
155 /* kernel/power/swsusp.c */
156 extern void swsusp_show_speed(struct timeval *, struct timeval *,
157 unsigned int, char *);
159 #ifdef CONFIG_SUSPEND
160 /* kernel/power/suspend.c */
161 extern const char *const pm_states[];
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)
169 return -ENOSYS;
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 */
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 */
184 #ifdef CONFIG_PM_SLEEP
185 /* kernel/power/main.c */
186 extern int pm_notifier_call_chain(unsigned long val);
187 #endif
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
197 * Suspend test levels
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
211 #define TEST_FIRST TEST_NONE
212 #define TEST_MAX (__TEST_AFTER_LAST - 1)
214 extern int pm_test_level;
216 #ifdef CONFIG_SUSPEND_FREEZER
217 static inline int suspend_freeze_processes(void)
219 return freeze_processes();
222 static inline void suspend_thaw_processes(void)
224 thaw_processes();
226 #else
227 static inline int suspend_freeze_processes(void)
229 return 0;
232 static inline void suspend_thaw_processes(void)
235 #endif