kernel/power/power.h

   1 #include <linux/suspend.h>
   2 #include <linux/utsname.h>
   3
   4 struct swsusp_info {
   5         struct new_utsname      uts;
   6         u32                     version_code;
   7         unsigned long           num_physpages;
   8         int                     cpus;
   9         unsigned long           image_pages;
  10         unsigned long           pages;
  11         unsigned long           size;
  12 } __attribute__((aligned(PAGE_SIZE)));
  13
  14 #ifdef CONFIG_HIBERNATION
  15 #ifdef CONFIG_ARCH_HIBERNATION_HEADER
  16 /* Maximum size of architecture specific data in a hibernation header */
  17 #define MAX_ARCH_HEADER_SIZE    (sizeof(struct new_utsname) + 4)
  18
  19 extern int arch_hibernation_header_save(void *addr, unsigned int max_size);
  20 extern int arch_hibernation_header_restore(void *addr);
  21
  22 static inline int init_header_complete(struct swsusp_info *info)
  23 {
  24         return arch_hibernation_header_save(info, MAX_ARCH_HEADER_SIZE);
  25 }
  26
  27 static inline char *check_image_kernel(struct swsusp_info *info)
  28 {
  29         return arch_hibernation_header_restore(info) ?
  30                         "architecture specific data" : NULL;
  31 }
  32 #endif /* CONFIG_ARCH_HIBERNATION_HEADER */
  33
  34 /*
  35  * Keep some memory free so that I/O operations can succeed without paging
  36  * [Might this be more than 4 MB?]
  37  */
  38 #define PAGES_FOR_IO    ((4096 * 1024) >> PAGE_SHIFT)
  39
  40 /*
  41  * Keep 1 MB of memory free so that device drivers can allocate some pages in
  42  * their .suspend() routines without breaking the suspend to disk.
  43  */
  44 #define SPARE_PAGES     ((1024 * 1024) >> PAGE_SHIFT)
  45
  46 /* kernel/power/disk.c */
  47 extern int hibernation_snapshot(int platform_mode);
  48 extern int hibernation_restore(int platform_mode);
  49 extern int hibernation_platform_enter(void);
  50 #endif
  51
  52 extern int pfn_is_nosave(unsigned long);
  53
  54 extern struct mutex pm_mutex;
  55
  56 #define power_attr(_name) \
  57 static struct subsys_attribute _name##_attr = { \
  58         .attr   = {                             \
  59                 .name = __stringify(_name),     \
  60                 .mode = 0644,                   \
  61         },                                      \
  62         .show   = _name##_show,                 \
  63         .store  = _name##_store,                \
  64 }
  65
  66 extern struct kset power_subsys;
  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 int snapshot_read_next(struct snapshot_handle *handle, size_t count);
 134 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
 135 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 136 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 137
 138 /*
 139  * This structure is used to pass the values needed for the identification
 140  * of the resume swap area from a user space to the kernel via the
 141  * SNAPSHOT_SET_SWAP_AREA ioctl
 142  */
 143 struct resume_swap_area {
 144         loff_t offset;
 145         u_int32_t dev;
 146 } __attribute__((packed));
 147
 148 #define SNAPSHOT_IOC_MAGIC      '3'
 149 #define SNAPSHOT_FREEZE                 _IO(SNAPSHOT_IOC_MAGIC, 1)
 150 #define SNAPSHOT_UNFREEZE               _IO(SNAPSHOT_IOC_MAGIC, 2)
 151 #define SNAPSHOT_ATOMIC_SNAPSHOT        _IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
 152 #define SNAPSHOT_ATOMIC_RESTORE         _IO(SNAPSHOT_IOC_MAGIC, 4)
 153 #define SNAPSHOT_FREE                   _IO(SNAPSHOT_IOC_MAGIC, 5)
 154 #define SNAPSHOT_SET_IMAGE_SIZE         _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
 155 #define SNAPSHOT_AVAIL_SWAP             _IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
 156 #define SNAPSHOT_GET_SWAP_PAGE          _IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
 157 #define SNAPSHOT_FREE_SWAP_PAGES        _IO(SNAPSHOT_IOC_MAGIC, 9)
 158 #define SNAPSHOT_SET_SWAP_FILE          _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
 159 #define SNAPSHOT_S2RAM                  _IO(SNAPSHOT_IOC_MAGIC, 11)
 160 #define SNAPSHOT_PMOPS                  _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
 161 #define SNAPSHOT_SET_SWAP_AREA          _IOW(SNAPSHOT_IOC_MAGIC, 13, \
 162                                                         struct resume_swap_area)
 163 #define SNAPSHOT_IOC_MAXNR      13
 164
 165 #define PMOPS_PREPARE   1
 166 #define PMOPS_ENTER     2
 167 #define PMOPS_FINISH    3
 168
 169 /* If unset, the snapshot device cannot be open. */
 170 extern atomic_t snapshot_device_available;
 171
 172 extern sector_t alloc_swapdev_block(int swap);
 173 extern void free_all_swap_pages(int swap);
 174 extern int swsusp_swap_in_use(void);
 175
 176 /*
 177  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
 178  * the image header.
 179  */
 180 #define SF_PLATFORM_MODE        1
 181
 182 /* kernel/power/disk.c */
 183 extern int swsusp_check(void);
 184 extern int swsusp_shrink_memory(void);
 185 extern void swsusp_free(void);
 186 extern int swsusp_resume(void);
 187 extern int swsusp_read(unsigned int *flags_p);
 188 extern int swsusp_write(unsigned int flags);
 189 extern void swsusp_close(void);
 190
 191 struct timeval;
 192 /* kernel/power/swsusp.c */
 193 extern void swsusp_show_speed(struct timeval *, struct timeval *,
 194                                 unsigned int, char *);
 195
 196 #ifdef CONFIG_SUSPEND
 197 /* kernel/power/main.c */
 198 extern int suspend_devices_and_enter(suspend_state_t state);
 199 #else /* !CONFIG_SUSPEND */
 200 static inline int suspend_devices_and_enter(suspend_state_t state)
 201 {
 202         return -ENOSYS;
 203 }
 204 #endif /* !CONFIG_SUSPEND */
 205
 206 /* kernel/power/common.c */
 207 extern struct blocking_notifier_head pm_chain_head;
 208
 209 static inline int pm_notifier_call_chain(unsigned long val)
 210 {
 211         return (blocking_notifier_call_chain(&pm_chain_head, val, NULL)
 212                         == NOTIFY_BAD) ? -EINVAL : 0;
 213 }