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 swsusp_shrink_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         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 unsigned long snapshot_get_image_size(void);
 132 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
 133 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
 134 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 135 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 136
 137 /* If unset, the snapshot device cannot be open. */
 138 extern atomic_t snapshot_device_available;
 139
 140 extern sector_t alloc_swapdev_block(int swap);
 141 extern void free_all_swap_pages(int swap);
 142 extern int swsusp_swap_in_use(void);
 143
 144 /*
 145  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
 146  * the image header.
 147  */
 148 #define SF_PLATFORM_MODE        1
 149
 150 /* kernel/power/hibernate.c */
 151 extern int swsusp_check(void);
 152 extern void swsusp_free(void);
 153 extern int swsusp_read(unsigned int *flags_p);
 154 extern int swsusp_write(unsigned int flags);
 155 extern void swsusp_close(fmode_t);
 156
 157 struct timeval;
 158 /* kernel/power/swsusp.c */
 159 extern void swsusp_show_speed(struct timeval *, struct timeval *,
 160                                 unsigned int, char *);
 161
 162 #ifdef CONFIG_SUSPEND
 163 /* kernel/power/suspend.c */
 164 extern const char *const pm_states[];
 165
 166 extern bool valid_state(suspend_state_t state);
 167 extern int suspend_devices_and_enter(suspend_state_t state);
 168 extern int enter_state(suspend_state_t state);
 169 #else /* !CONFIG_SUSPEND */
 170 static inline int suspend_devices_and_enter(suspend_state_t state)
 171 {
 172         return -ENOSYS;
 173 }
 174 static inline int enter_state(suspend_state_t state) { return -ENOSYS; }
 175 static inline bool valid_state(suspend_state_t state) { return false; }
 176 #endif /* !CONFIG_SUSPEND */
 177
 178 #ifdef CONFIG_PM_TEST_SUSPEND
 179 /* kernel/power/suspend_test.c */
 180 extern void suspend_test_start(void);
 181 extern void suspend_test_finish(const char *label);
 182 #else /* !CONFIG_PM_TEST_SUSPEND */
 183 static inline void suspend_test_start(void) {}
 184 static inline void suspend_test_finish(const char *label) {}
 185 #endif /* !CONFIG_PM_TEST_SUSPEND */
 186
 187 #ifdef CONFIG_PM_SLEEP
 188 /* kernel/power/main.c */
 189 extern int pm_notifier_call_chain(unsigned long val);
 190 #endif
 191
 192 #ifdef CONFIG_HIGHMEM
 193 int restore_highmem(void);
 194 #else
 195 static inline unsigned int count_highmem_pages(void) { return 0; }
 196 static inline int restore_highmem(void) { return 0; }
 197 #endif
 198
 199 /*
 200  * Suspend test levels
 201  */
 202 enum {
 203         /* keep first */
 204         TEST_NONE,
 205         TEST_CORE,
 206         TEST_CPUS,
 207         TEST_PLATFORM,
 208         TEST_DEVICES,
 209         TEST_FREEZER,
 210         /* keep last */
 211         __TEST_AFTER_LAST
 212 };
 213
 214 #define TEST_FIRST      TEST_NONE
 215 #define TEST_MAX        (__TEST_AFTER_LAST - 1)
 216
 217 extern int pm_test_level;
 218
 219 #ifdef CONFIG_SUSPEND_FREEZER
 220 static inline int suspend_freeze_processes(void)
 221 {
 222         return freeze_processes();
 223 }
 224
 225 static inline void suspend_thaw_processes(void)
 226 {
 227         thaw_processes();
 228 }
 229 #else
 230 static inline int suspend_freeze_processes(void)
 231 {
 232         return 0;
 233 }
 234
 235 static inline void suspend_thaw_processes(void)
 236 {
 237 }
 238 #endif