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 /* kernel/power/snapshot.c */
  18 extern void __init hibernate_reserved_size_init(void);
  19 extern void __init hibernate_image_size_init(void);
  20
  21 #ifdef CONFIG_ARCH_HIBERNATION_HEADER
  22 /* Maximum size of architecture specific data in a hibernation header */
  23 #define MAX_ARCH_HEADER_SIZE    (sizeof(struct new_utsname) + 4)
  24
  25 extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
  26 extern int arch_hibernation_header_restore(void *addr);
  27
  28 static inline int init_header_complete(struct swsusp_info *info)
  29 {
  30         return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
  31 }
  32
  33 static inline char *check_image_kernel(struct swsusp_info *info)
  34 {
  35         return arch_hibernation_header_restore(info) ?
  36                         "architecture specific data" : NULL;
  37 }
  38 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
  39
  40 /*
  41  * Keep some memory free so that I/O operations can succeed without paging
  42  * [Might this be more than 4 MB?]
  43  */
  44 #define PAGES_FOR_IO    ((4096 * 1024) >> PAGE_SHIFT)
  45
  46 /*
  47  * Keep 1 MB of memory free so that device drivers can allocate some pages in
  48  * their .suspend() routines without breaking the suspend to disk.
  49  */
  50 #define SPARE_PAGES     ((1024 * 1024) >> PAGE_SHIFT)
  51
  52 /* kernel/power/hibernate.c */
  53 extern bool freezer_test_done;
  54
  55 extern int hibernation_snapshot(int platform_mode);
  56 extern int hibernation_restore(int platform_mode);
  57 extern int hibernation_platform_enter(void);
  58
  59 #else /* !CONFIG_HIBERNATION */
  60
  61 static inline void hibernate_reserved_size_init(void) {}
  62 static inline void hibernate_image_size_init(void) {}
  63 #endif /* !CONFIG_HIBERNATION */
  64
  65 extern int pfn_is_nosave(unsigned long);
  66
  67 #define power_attr(_name) \
  68 static struct kobj_attribute _name##_attr = {   \
  69         .attr   = {                             \
  70                 .name = __stringify(_name),     \
  71                 .mode = 0644,                   \
  72         },                                      \
  73         .show   = _name##_show,                 \
  74         .store  = _name##_store,                \
  75 }
  76
  77 /* Preferred image size in bytes (default 500 MB) */
  78 extern unsigned long image_size;
  79 /* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
  80 extern unsigned long reserved_size;
  81 extern int in_suspend;
  82 extern dev_t swsusp_resume_device;
  83 extern sector_t swsusp_resume_block;
  84
  85 extern asmlinkage int swsusp_arch_suspend(void);
  86 extern asmlinkage int swsusp_arch_resume(void);
  87
  88 extern int create_basic_memory_bitmaps(void);
  89 extern void free_basic_memory_bitmaps(void);
  90 extern int hibernate_preallocate_memory(void);
  91
  92 /**
  93  *      Auxiliary structure used for reading the snapshot image data and
  94  *      metadata from and writing them to the list of page backup entries
  95  *      (PBEs) which is the main data structure of swsusp.
  96  *
  97  *      Using struct snapshot_handle we can transfer the image, including its
  98  *      metadata, as a continuous sequence of bytes with the help of
  99  *      snapshot_read_next() and snapshot_write_next().
 100  *
 101  *      The code that writes the image to a storage or transfers it to
 102  *      the user land is required to use snapshot_read_next() for this
 103  *      purpose and it should not make any assumptions regarding the internal
 104  *      structure of the image.  Similarly, the code that reads the image from
 105  *      a storage or transfers it from the user land is required to use
 106  *      snapshot_write_next().
 107  *
 108  *      This may allow us to change the internal structure of the image
 109  *      in the future with considerably less effort.
 110  */
 111
 112 struct snapshot_handle {
 113         unsigned int    cur;    /* number of the block of PAGE_SIZE bytes the
 114                                  * next operation will refer to (ie. current)
 115                                  */
 116         void            *buffer;        /* address of the block to read from
 117                                          * or write to
 118                                          */
 119         int             sync_read;      /* Set to one to notify the caller of
 120                                          * snapshot_write_next() that it may
 121                                          * need to call wait_on_bio_chain()
 122                                          */
 123 };
 124
 125 /* This macro returns the address from/to which the caller of
 126  * snapshot_read_next()/snapshot_write_next() is allowed to
 127  * read/write data after the function returns
 128  */
 129 #define data_of(handle) ((handle).buffer)
 130
 131 extern unsigned int snapshot_additional_pages(struct zone *zone);
 132 extern unsigned long snapshot_get_image_size(void);
 133 extern int snapshot_read_next(struct snapshot_handle *handle);
 134 extern int snapshot_write_next(struct snapshot_handle *handle);
 135 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 136 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 137
 138 /* If unset, the snapshot device cannot be open. */
 139 extern atomic_t snapshot_device_available;
 140
 141 extern sector_t alloc_swapdev_block(int swap);
 142 extern void free_all_swap_pages(int swap);
 143 extern int swsusp_swap_in_use(void);
 144
 145 /*
 146  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
 147  * the image header.
 148  */
 149 #define SF_PLATFORM_MODE        1
 150 #define SF_NOCOMPRESS_MODE      2
 151 #define SF_CRC32_MODE           4
 152
 153 /* kernel/power/hibernate.c */
 154 extern int swsusp_check(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(fmode_t);
 159
 160 /* kernel/power/block_io.c */
 161 extern struct block_device *hib_resume_bdev;
 162
 163 extern int hib_bio_read_page(pgoff_t page_off, void *addr,
 164                 struct bio **bio_chain);
 165 extern int hib_bio_write_page(pgoff_t page_off, void *addr,
 166                 struct bio **bio_chain);
 167 extern int hib_wait_on_bio_chain(struct bio **bio_chain);
 168
 169 struct timeval;
 170 /* kernel/power/swsusp.c */
 171 extern void swsusp_show_speed(struct timeval *, struct timeval *,
 172                                 unsigned int, char *);
 173
 174 #ifdef CONFIG_SUSPEND
 175 /* kernel/power/suspend.c */
 176 extern const char *const pm_states[];
 177
 178 extern bool valid_state(suspend_state_t state);
 179 extern int suspend_devices_and_enter(suspend_state_t state);
 180 #else /* !CONFIG_SUSPEND */
 181 static inline int suspend_devices_and_enter(suspend_state_t state)
 182 {
 183         return -ENOSYS;
 184 }
 185 static inline bool valid_state(suspend_state_t state) { return false; }
 186 #endif /* !CONFIG_SUSPEND */
 187
 188 #ifdef CONFIG_PM_TEST_SUSPEND
 189 /* kernel/power/suspend_test.c */
 190 extern void suspend_test_start(void);
 191 extern void suspend_test_finish(const char *label);
 192 #else /* !CONFIG_PM_TEST_SUSPEND */
 193 static inline void suspend_test_start(void) {}
 194 static inline void suspend_test_finish(const char *label) {}
 195 #endif /* !CONFIG_PM_TEST_SUSPEND */
 196
 197 #ifdef CONFIG_PM_SLEEP
 198 /* kernel/power/main.c */
 199 extern int pm_notifier_call_chain(unsigned long val);
 200 #endif
 201
 202 #ifdef CONFIG_HIGHMEM
 203 int restore_highmem(void);
 204 #else
 205 static inline unsigned int count_highmem_pages(void) { return 0; }
 206 static inline int restore_highmem(void) { return 0; }
 207 #endif
 208
 209 /*
 210  * Suspend test levels
 211  */
 212 enum {
 213         /* keep first */
 214         TEST_NONE,
 215         TEST_CORE,
 216         TEST_CPUS,
 217         TEST_PLATFORM,
 218         TEST_DEVICES,
 219         TEST_FREEZER,
 220         /* keep last */
 221         __TEST_AFTER_LAST
 222 };
 223
 224 #define TEST_FIRST      TEST_NONE
 225 #define TEST_MAX        (__TEST_AFTER_LAST - 1)
 226
 227 extern int pm_test_level;
 228
 229 #ifdef CONFIG_SUSPEND_FREEZER
 230 static inline int suspend_freeze_processes(void)
 231 {
 232         int error;
 233
 234         error = freeze_processes();
 235         /*
 236          * freeze_processes() automatically thaws every task if freezing
 237          * fails. So we need not do anything extra upon error.
 238          */
 239         if (error)
 240                 return error;
 241
 242         error = freeze_kernel_threads();
 243         /*
 244          * freeze_kernel_threads() thaws only kernel threads upon freezing
 245          * failure. So we have to thaw the userspace tasks ourselves.
 246          */
 247         if (error)
 248                 thaw_processes();
 249
 250         return error;
 251 }
 252
 253 static inline void suspend_thaw_processes(void)
 254 {
 255         thaw_processes();
 256 }
 257 #else
 258 static inline int suspend_freeze_processes(void)
 259 {
 260         return 0;
 261 }
 262
 263 static inline void suspend_thaw_processes(void)
 264 {
 265 }
 266 #endif