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/disk.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 extern struct mutex pm_mutex;
  57
  58 #define power_attr(_name) \
  59 static struct kobj_attribute _name##_attr = {   \
  60         .attr   = {                             \
  61                 .name = __stringify(_name),     \
  62                 .mode = 0644,                   \
  63         },                                      \
  64         .show   = _name##_show,                 \
  65         .store  = _name##_store,                \
  66 }
  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 unsigned long snapshot_get_image_size(void);
 134 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
 135 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
 136 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 137 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 138
 139 /* If unset, the snapshot device cannot be open. */
 140 extern atomic_t snapshot_device_available;
 141
 142 extern sector_t alloc_swapdev_block(int swap);
 143 extern void free_all_swap_pages(int swap);
 144 extern int swsusp_swap_in_use(void);
 145
 146 /*
 147  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
 148  * the image header.
 149  */
 150 #define SF_PLATFORM_MODE        1
 151
 152 /* kernel/power/disk.c */
 153 extern int swsusp_check(void);
 154 extern int swsusp_shrink_memory(void);
 155 extern void swsusp_free(void);
 156 extern int swsusp_read(unsigned int *flags_p);
 157 extern int swsusp_write(unsigned int flags);
 158 extern void swsusp_close(void);
 159
 160 struct timeval;
 161 /* kernel/power/swsusp.c */
 162 extern void swsusp_show_speed(struct timeval *, struct timeval *,
 163                                 unsigned int, char *);
 164
 165 #ifdef CONFIG_SUSPEND
 166 /* kernel/power/main.c */
 167 extern int suspend_devices_and_enter(suspend_state_t state);
 168 #else /* !CONFIG_SUSPEND */
 169 static inline int suspend_devices_and_enter(suspend_state_t state)
 170 {
 171         return -ENOSYS;
 172 }
 173 #endif /* !CONFIG_SUSPEND */
 174
 175 #ifdef CONFIG_PM_SLEEP
 176 /* kernel/power/main.c */
 177 extern int pm_notifier_call_chain(unsigned long val);
 178 #endif
 179
 180 #ifdef CONFIG_HIGHMEM
 181 unsigned int count_highmem_pages(void);
 182 int restore_highmem(void);
 183 #else
 184 static inline unsigned int count_highmem_pages(void) { return 0; }
 185 static inline int restore_highmem(void) { return 0; }
 186 #endif
 187
 188 /*
 189  * Suspend test levels
 190  */
 191 enum {
 192         /* keep first */
 193         TEST_NONE,
 194         TEST_CORE,
 195         TEST_CPUS,
 196         TEST_PLATFORM,
 197         TEST_DEVICES,
 198         TEST_FREEZER,
 199         /* keep last */
 200         __TEST_AFTER_LAST
 201 };
 202
 203 #define TEST_FIRST      TEST_NONE
 204 #define TEST_MAX        (__TEST_AFTER_LAST - 1)
 205
 206 extern int pm_test_level;
 207
 208 #ifdef CONFIG_SUSPEND_FREEZER
 209 static inline int suspend_freeze_processes(void)
 210 {
 211         return freeze_processes();
 212 }
 213
 214 static inline void suspend_thaw_processes(void)
 215 {
 216         thaw_processes();
 217 }
 218 #else
 219 static inline int suspend_freeze_processes(void)
 220 {
 221         return 0;
 222 }
 223
 224 static inline void suspend_thaw_processes(void)
 225 {
 226 }
 227 #endif