root/kernel/power/power.h

INCLUDED FROM

DEFINITIONS

1. init_header_complete
2. check_image_kernel
3. enable_restore_image_protection
4. hibernate_reserved_size_init
5. hibernate_image_size_init
6. suspend_devices_and_enter
7. suspend_test_start
8. suspend_test_finish
9. count_highmem_pages
10. restore_highmem
11. suspend_freeze_processes
12. suspend_thaw_processes
13. suspend_freeze_processes
14. suspend_thaw_processes
15. pm_autosleep_init
16. pm_autosleep_lock
17. pm_autosleep_unlock
18. pm_autosleep_state

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #include <linux/suspend.h>
   3 #include <linux/suspend_ioctls.h>
   4 #include <linux/utsname.h>
   5 #include <linux/freezer.h>
   6 #include <linux/compiler.h>
   7 
   8 struct swsusp_info {
   9         struct new_utsname      uts;
  10         u32                     version_code;
  11         unsigned long           num_physpages;
  12         int                     cpus;
  13         unsigned long           image_pages;
  14         unsigned long           pages;
  15         unsigned long           size;
  16 } __aligned(PAGE_SIZE);
  17 
  18 #ifdef CONFIG_HIBERNATION
  19 /* kernel/power/snapshot.c */
  20 extern void __init hibernate_reserved_size_init(void);
  21 extern void __init hibernate_image_size_init(void);
  22 
  23 #ifdef CONFIG_ARCH_HIBERNATION_HEADER
  24 /* Maximum size of architecture specific data in a hibernation header */
  25 #define MAX_ARCH_HEADER_SIZE    (sizeof(struct new_utsname) + 4)
  26 
  27 extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
  28 extern int arch_hibernation_header_restore(void *addr);
  29 
  30 static inline int init_header_complete(struct swsusp_info *info)
  31 {
  32         return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
  33 }
  34 
  35 static inline char *check_image_kernel(struct swsusp_info *info)
  36 {
  37         return arch_hibernation_header_restore(info) ?
  38                         "architecture specific data" : NULL;
  39 }
  40 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
  41 
  42 extern int hibernate_resume_nonboot_cpu_disable(void);
  43 
  44 /*
  45  * Keep some memory free so that I/O operations can succeed without paging
  46  * [Might this be more than 4 MB?]
  47  */
  48 #define PAGES_FOR_IO    ((4096 * 1024) >> PAGE_SHIFT)
  49 
  50 /*
  51  * Keep 1 MB of memory free so that device drivers can allocate some pages in
  52  * their .suspend() routines without breaking the suspend to disk.
  53  */
  54 #define SPARE_PAGES     ((1024 * 1024) >> PAGE_SHIFT)
  55 
  56 asmlinkage int swsusp_save(void);
  57 
  58 /* kernel/power/hibernate.c */
  59 extern bool freezer_test_done;
  60 
  61 extern int hibernation_snapshot(int platform_mode);
  62 extern int hibernation_restore(int platform_mode);
  63 extern int hibernation_platform_enter(void);
  64 
  65 #ifdef CONFIG_STRICT_KERNEL_RWX
  66 /* kernel/power/snapshot.c */
  67 extern void enable_restore_image_protection(void);
  68 #else
  69 static inline void enable_restore_image_protection(void) {}
  70 #endif /* CONFIG_STRICT_KERNEL_RWX */
  71 
  72 #else /* !CONFIG_HIBERNATION */
  73 
  74 static inline void hibernate_reserved_size_init(void) {}
  75 static inline void hibernate_image_size_init(void) {}
  76 #endif /* !CONFIG_HIBERNATION */
  77 
  78 #define power_attr(_name) \
  79 static struct kobj_attribute _name##_attr = {   \
  80         .attr   = {                             \
  81                 .name = __stringify(_name),     \
  82                 .mode = 0644,                   \
  83         },                                      \
  84         .show   = _name##_show,                 \
  85         .store  = _name##_store,                \
  86 }
  87 
  88 #define power_attr_ro(_name) \
  89 static struct kobj_attribute _name##_attr = {   \
  90         .attr   = {                             \
  91                 .name = __stringify(_name),     \
  92                 .mode = S_IRUGO,                \
  93         },                                      \
  94         .show   = _name##_show,                 \
  95 }
  96 
  97 /* Preferred image size in bytes (default 500 MB) */
  98 extern unsigned long image_size;
  99 /* Size of memory reserved for drivers (default SPARE_PAGES x PAGE_SIZE) */
 100 extern unsigned long reserved_size;
 101 extern int in_suspend;
 102 extern dev_t swsusp_resume_device;
 103 extern sector_t swsusp_resume_block;
 104 
 105 extern int create_basic_memory_bitmaps(void);
 106 extern void free_basic_memory_bitmaps(void);
 107 extern int hibernate_preallocate_memory(void);
 108 
 109 extern void clear_free_pages(void);
 110 
 111 /**
 112  *      Auxiliary structure used for reading the snapshot image data and
 113  *      metadata from and writing them to the list of page backup entries
 114  *      (PBEs) which is the main data structure of swsusp.
 115  *
 116  *      Using struct snapshot_handle we can transfer the image, including its
 117  *      metadata, as a continuous sequence of bytes with the help of
 118  *      snapshot_read_next() and snapshot_write_next().
 119  *
 120  *      The code that writes the image to a storage or transfers it to
 121  *      the user land is required to use snapshot_read_next() for this
 122  *      purpose and it should not make any assumptions regarding the internal
 123  *      structure of the image.  Similarly, the code that reads the image from
 124  *      a storage or transfers it from the user land is required to use
 125  *      snapshot_write_next().
 126  *
 127  *      This may allow us to change the internal structure of the image
 128  *      in the future with considerably less effort.
 129  */
 130 
 131 struct snapshot_handle {
 132         unsigned int    cur;    /* number of the block of PAGE_SIZE bytes the
 133                                  * next operation will refer to (ie. current)
 134                                  */
 135         void            *buffer;        /* address of the block to read from
 136                                          * or write to
 137                                          */
 138         int             sync_read;      /* Set to one to notify the caller of
 139                                          * snapshot_write_next() that it may
 140                                          * need to call wait_on_bio_chain()
 141                                          */
 142 };
 143 
 144 /* This macro returns the address from/to which the caller of
 145  * snapshot_read_next()/snapshot_write_next() is allowed to
 146  * read/write data after the function returns
 147  */
 148 #define data_of(handle) ((handle).buffer)
 149 
 150 extern unsigned int snapshot_additional_pages(struct zone *zone);
 151 extern unsigned long snapshot_get_image_size(void);
 152 extern int snapshot_read_next(struct snapshot_handle *handle);
 153 extern int snapshot_write_next(struct snapshot_handle *handle);
 154 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 155 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 156 
 157 /* If unset, the snapshot device cannot be open. */
 158 extern atomic_t snapshot_device_available;
 159 
 160 extern sector_t alloc_swapdev_block(int swap);
 161 extern void free_all_swap_pages(int swap);
 162 extern int swsusp_swap_in_use(void);
 163 
 164 /*
 165  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
 166  * the image header.
 167  */
 168 #define SF_PLATFORM_MODE        1
 169 #define SF_NOCOMPRESS_MODE      2
 170 #define SF_CRC32_MODE           4
 171 
 172 /* kernel/power/hibernate.c */
 173 extern int swsusp_check(void);
 174 extern void swsusp_free(void);
 175 extern int swsusp_read(unsigned int *flags_p);
 176 extern int swsusp_write(unsigned int flags);
 177 extern void swsusp_close(fmode_t);
 178 #ifdef CONFIG_SUSPEND
 179 extern int swsusp_unmark(void);
 180 #endif
 181 
 182 struct timeval;
 183 /* kernel/power/swsusp.c */
 184 extern void swsusp_show_speed(ktime_t, ktime_t, unsigned int, char *);
 185 
 186 #ifdef CONFIG_SUSPEND
 187 /* kernel/power/suspend.c */
 188 extern const char * const pm_labels[];
 189 extern const char *pm_states[];
 190 extern const char *mem_sleep_states[];
 191 
 192 extern int suspend_devices_and_enter(suspend_state_t state);
 193 #else /* !CONFIG_SUSPEND */
 194 #define mem_sleep_current       PM_SUSPEND_ON
 195 
 196 static inline int suspend_devices_and_enter(suspend_state_t state)
 197 {
 198         return -ENOSYS;
 199 }
 200 #endif /* !CONFIG_SUSPEND */
 201 
 202 #ifdef CONFIG_PM_TEST_SUSPEND
 203 /* kernel/power/suspend_test.c */
 204 extern void suspend_test_start(void);
 205 extern void suspend_test_finish(const char *label);
 206 #else /* !CONFIG_PM_TEST_SUSPEND */
 207 static inline void suspend_test_start(void) {}
 208 static inline void suspend_test_finish(const char *label) {}
 209 #endif /* !CONFIG_PM_TEST_SUSPEND */
 210 
 211 #ifdef CONFIG_PM_SLEEP
 212 /* kernel/power/main.c */
 213 extern int __pm_notifier_call_chain(unsigned long val, int nr_to_call,
 214                                     int *nr_calls);
 215 extern int pm_notifier_call_chain(unsigned long val);
 216 #endif
 217 
 218 #ifdef CONFIG_HIGHMEM
 219 int restore_highmem(void);
 220 #else
 221 static inline unsigned int count_highmem_pages(void) { return 0; }
 222 static inline int restore_highmem(void) { return 0; }
 223 #endif
 224 
 225 /*
 226  * Suspend test levels
 227  */
 228 enum {
 229         /* keep first */
 230         TEST_NONE,
 231         TEST_CORE,
 232         TEST_CPUS,
 233         TEST_PLATFORM,
 234         TEST_DEVICES,
 235         TEST_FREEZER,
 236         /* keep last */
 237         __TEST_AFTER_LAST
 238 };
 239 
 240 #define TEST_FIRST      TEST_NONE
 241 #define TEST_MAX        (__TEST_AFTER_LAST - 1)
 242 
 243 #ifdef CONFIG_PM_SLEEP_DEBUG
 244 extern int pm_test_level;
 245 #else
 246 #define pm_test_level   (TEST_NONE)
 247 #endif
 248 
 249 #ifdef CONFIG_SUSPEND_FREEZER
 250 static inline int suspend_freeze_processes(void)
 251 {
 252         int error;
 253 
 254         error = freeze_processes();
 255         /*
 256          * freeze_processes() automatically thaws every task if freezing
 257          * fails. So we need not do anything extra upon error.
 258          */
 259         if (error)
 260                 return error;
 261 
 262         error = freeze_kernel_threads();
 263         /*
 264          * freeze_kernel_threads() thaws only kernel threads upon freezing
 265          * failure. So we have to thaw the userspace tasks ourselves.
 266          */
 267         if (error)
 268                 thaw_processes();
 269 
 270         return error;
 271 }
 272 
 273 static inline void suspend_thaw_processes(void)
 274 {
 275         thaw_processes();
 276 }
 277 #else
 278 static inline int suspend_freeze_processes(void)
 279 {
 280         return 0;
 281 }
 282 
 283 static inline void suspend_thaw_processes(void)
 284 {
 285 }
 286 #endif
 287 
 288 #ifdef CONFIG_PM_AUTOSLEEP
 289 
 290 /* kernel/power/autosleep.c */
 291 extern int pm_autosleep_init(void);
 292 extern int pm_autosleep_lock(void);
 293 extern void pm_autosleep_unlock(void);
 294 extern suspend_state_t pm_autosleep_state(void);
 295 extern int pm_autosleep_set_state(suspend_state_t state);
 296 
 297 #else /* !CONFIG_PM_AUTOSLEEP */
 298 
 299 static inline int pm_autosleep_init(void) { return 0; }
 300 static inline int pm_autosleep_lock(void) { return 0; }
 301 static inline void pm_autosleep_unlock(void) {}
 302 static inline suspend_state_t pm_autosleep_state(void) { return PM_SUSPEND_ON; }
 303 
 304 #endif /* !CONFIG_PM_AUTOSLEEP */
 305 
 306 #ifdef CONFIG_PM_WAKELOCKS
 307 
 308 /* kernel/power/wakelock.c */
 309 extern ssize_t pm_show_wakelocks(char *buf, bool show_active);
 310 extern int pm_wake_lock(const char *buf);
 311 extern int pm_wake_unlock(const char *buf);
 312 
 313 #endif /* !CONFIG_PM_WAKELOCKS */