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
  15
  16 #ifdef CONFIG_SOFTWARE_SUSPEND
  17 extern int pm_suspend_disk(void);
  18
  19 #else
  20 static inline int pm_suspend_disk(void)
  21 {
  22         return -EPERM;
  23 }
  24 #endif
  25
  26 extern int pfn_is_nosave(unsigned long);
  27
  28 extern struct mutex pm_mutex;
  29
  30 #define power_attr(_name) \
  31 static struct subsys_attribute _name##_attr = { \
  32         .attr   = {                             \
  33                 .name = __stringify(_name),     \
  34                 .mode = 0644,                   \
  35         },                                      \
  36         .show   = _name##_show,                 \
  37         .store  = _name##_store,                \
  38 }
  39
  40 extern struct kset power_subsys;
  41
  42 /* Preferred image size in bytes (default 500 MB) */
  43 extern unsigned long image_size;
  44 extern int in_suspend;
  45 extern dev_t swsusp_resume_device;
  46 extern sector_t swsusp_resume_block;
  47
  48 extern asmlinkage int swsusp_arch_suspend(void);
  49 extern asmlinkage int swsusp_arch_resume(void);
  50
  51 extern int create_basic_memory_bitmaps(void);
  52 extern void free_basic_memory_bitmaps(void);
  53 extern unsigned int count_data_pages(void);
  54
  55 /**
  56  *      Auxiliary structure used for reading the snapshot image data and
  57  *      metadata from and writing them to the list of page backup entries
  58  *      (PBEs) which is the main data structure of swsusp.
  59  *
  60  *      Using struct snapshot_handle we can transfer the image, including its
  61  *      metadata, as a continuous sequence of bytes with the help of
  62  *      snapshot_read_next() and snapshot_write_next().
  63  *
  64  *      The code that writes the image to a storage or transfers it to
  65  *      the user land is required to use snapshot_read_next() for this
  66  *      purpose and it should not make any assumptions regarding the internal
  67  *      structure of the image.  Similarly, the code that reads the image from
  68  *      a storage or transfers it from the user land is required to use
  69  *      snapshot_write_next().
  70  *
  71  *      This may allow us to change the internal structure of the image
  72  *      in the future with considerably less effort.
  73  */
  74
  75 struct snapshot_handle {
  76         loff_t          offset; /* number of the last byte ready for reading
  77                                  * or writing in the sequence
  78                                  */
  79         unsigned int    cur;    /* number of the block of PAGE_SIZE bytes the
  80                                  * next operation will refer to (ie. current)
  81                                  */
  82         unsigned int    cur_offset;     /* offset with respect to the current
  83                                          * block (for the next operation)
  84                                          */
  85         unsigned int    prev;   /* number of the block of PAGE_SIZE bytes that
  86                                  * was the current one previously
  87                                  */
  88         void            *buffer;        /* address of the block to read from
  89                                          * or write to
  90                                          */
  91         unsigned int    buf_offset;     /* location to read from or write to,
  92                                          * given as a displacement from 'buffer'
  93                                          */
  94         int             sync_read;      /* Set to one to notify the caller of
  95                                          * snapshot_write_next() that it may
  96                                          * need to call wait_on_bio_chain()
  97                                          */
  98 };
  99
 100 /* This macro returns the address from/to which the caller of
 101  * snapshot_read_next()/snapshot_write_next() is allowed to
 102  * read/write data after the function returns
 103  */
 104 #define data_of(handle) ((handle).buffer + (handle).buf_offset)
 105
 106 extern unsigned int snapshot_additional_pages(struct zone *zone);
 107 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
 108 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
 109 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 110 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 111
 112 /*
 113  * This structure is used to pass the values needed for the identification
 114  * of the resume swap area from a user space to the kernel via the
 115  * SNAPSHOT_SET_SWAP_AREA ioctl
 116  */
 117 struct resume_swap_area {
 118         loff_t offset;
 119         u_int32_t dev;
 120 } __attribute__((packed));
 121
 122 #define SNAPSHOT_IOC_MAGIC      '3'
 123 #define SNAPSHOT_FREEZE                 _IO(SNAPSHOT_IOC_MAGIC, 1)
 124 #define SNAPSHOT_UNFREEZE               _IO(SNAPSHOT_IOC_MAGIC, 2)
 125 #define SNAPSHOT_ATOMIC_SNAPSHOT        _IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
 126 #define SNAPSHOT_ATOMIC_RESTORE         _IO(SNAPSHOT_IOC_MAGIC, 4)
 127 #define SNAPSHOT_FREE                   _IO(SNAPSHOT_IOC_MAGIC, 5)
 128 #define SNAPSHOT_SET_IMAGE_SIZE         _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
 129 #define SNAPSHOT_AVAIL_SWAP             _IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
 130 #define SNAPSHOT_GET_SWAP_PAGE          _IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
 131 #define SNAPSHOT_FREE_SWAP_PAGES        _IO(SNAPSHOT_IOC_MAGIC, 9)
 132 #define SNAPSHOT_SET_SWAP_FILE          _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
 133 #define SNAPSHOT_S2RAM                  _IO(SNAPSHOT_IOC_MAGIC, 11)
 134 #define SNAPSHOT_PMOPS                  _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
 135 #define SNAPSHOT_SET_SWAP_AREA          _IOW(SNAPSHOT_IOC_MAGIC, 13, \
 136                                                         struct resume_swap_area)
 137 #define SNAPSHOT_IOC_MAXNR      13
 138
 139 #define PMOPS_PREPARE   1
 140 #define PMOPS_ENTER     2
 141 #define PMOPS_FINISH    3
 142
 143 /* If unset, the snapshot device cannot be open. */
 144 extern atomic_t snapshot_device_available;
 145
 146 /**
 147  *      The bitmap is used for tracing allocated swap pages
 148  *
 149  *      The entire bitmap consists of a number of bitmap_page
 150  *      structures linked with the help of the .next member.
 151  *      Thus each page can be allocated individually, so we only
 152  *      need to make 0-order memory allocations to create
 153  *      the bitmap.
 154  */
 155
 156 #define BITMAP_PAGE_SIZE        (PAGE_SIZE - sizeof(void *))
 157 #define BITMAP_PAGE_CHUNKS      (BITMAP_PAGE_SIZE / sizeof(long))
 158 #define BITS_PER_CHUNK          (sizeof(long) * 8)
 159 #define BITMAP_PAGE_BITS        (BITMAP_PAGE_CHUNKS * BITS_PER_CHUNK)
 160
 161 struct bitmap_page {
 162         unsigned long           chunks[BITMAP_PAGE_CHUNKS];
 163         struct bitmap_page      *next;
 164 };
 165
 166 extern void free_bitmap(struct bitmap_page *bitmap);
 167 extern struct bitmap_page *alloc_bitmap(unsigned int nr_bits);
 168 extern sector_t alloc_swapdev_block(int swap, struct bitmap_page *bitmap);
 169 extern void free_all_swap_pages(int swap, struct bitmap_page *bitmap);
 170
 171 extern int swsusp_check(void);
 172 extern int swsusp_shrink_memory(void);
 173 extern void swsusp_free(void);
 174 extern int swsusp_suspend(void);
 175 extern int swsusp_resume(void);
 176 extern int swsusp_read(void);
 177 extern int swsusp_write(void);
 178 extern void swsusp_close(void);
 179 extern int suspend_enter(suspend_state_t state);
 180
 181 struct timeval;
 182 extern void swsusp_show_speed(struct timeval *, struct timeval *,
 183                                 unsigned int, char *);