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 /*
  18  * Keep some memory free so that I/O operations can succeed without paging
  19  * [Might this be more than 4 MB?]
  20  */
  21 #define PAGES_FOR_IO    ((4096 * 1024) >> PAGE_SHIFT)
  22 /*
  23  * Keep 1 MB of memory free so that device drivers can allocate some pages in
  24  * their .suspend() routines without breaking the suspend to disk.
  25  */
  26 #define SPARE_PAGES     ((1024 * 1024) >> PAGE_SHIFT)
  27
  28 extern int pm_suspend_disk(void);
  29 #else
  30 static inline int pm_suspend_disk(void)
  31 {
  32         return -EPERM;
  33 }
  34 #endif
  35
  36 extern int pfn_is_nosave(unsigned long);
  37
  38 extern struct mutex pm_mutex;
  39
  40 #define power_attr(_name) \
  41 static struct subsys_attribute _name##_attr = { \
  42         .attr   = {                             \
  43                 .name = __stringify(_name),     \
  44                 .mode = 0644,                   \
  45         },                                      \
  46         .show   = _name##_show,                 \
  47         .store  = _name##_store,                \
  48 }
  49
  50 extern struct kset power_subsys;
  51
  52 /* Preferred image size in bytes (default 500 MB) */
  53 extern unsigned long image_size;
  54 extern int in_suspend;
  55 extern dev_t swsusp_resume_device;
  56 extern sector_t swsusp_resume_block;
  57
  58 extern asmlinkage int swsusp_arch_suspend(void);
  59 extern asmlinkage int swsusp_arch_resume(void);
  60
  61 extern int create_basic_memory_bitmaps(void);
  62 extern void free_basic_memory_bitmaps(void);
  63 extern unsigned int count_data_pages(void);
  64
  65 /**
  66  *      Auxiliary structure used for reading the snapshot image data and
  67  *      metadata from and writing them to the list of page backup entries
  68  *      (PBEs) which is the main data structure of swsusp.
  69  *
  70  *      Using struct snapshot_handle we can transfer the image, including its
  71  *      metadata, as a continuous sequence of bytes with the help of
  72  *      snapshot_read_next() and snapshot_write_next().
  73  *
  74  *      The code that writes the image to a storage or transfers it to
  75  *      the user land is required to use snapshot_read_next() for this
  76  *      purpose and it should not make any assumptions regarding the internal
  77  *      structure of the image.  Similarly, the code that reads the image from
  78  *      a storage or transfers it from the user land is required to use
  79  *      snapshot_write_next().
  80  *
  81  *      This may allow us to change the internal structure of the image
  82  *      in the future with considerably less effort.
  83  */
  84
  85 struct snapshot_handle {
  86         loff_t          offset; /* number of the last byte ready for reading
  87                                  * or writing in the sequence
  88                                  */
  89         unsigned int    cur;    /* number of the block of PAGE_SIZE bytes the
  90                                  * next operation will refer to (ie. current)
  91                                  */
  92         unsigned int    cur_offset;     /* offset with respect to the current
  93                                          * block (for the next operation)
  94                                          */
  95         unsigned int    prev;   /* number of the block of PAGE_SIZE bytes that
  96                                  * was the current one previously
  97                                  */
  98         void            *buffer;        /* address of the block to read from
  99                                          * or write to
 100                                          */
 101         unsigned int    buf_offset;     /* location to read from or write to,
 102                                          * given as a displacement from 'buffer'
 103                                          */
 104         int             sync_read;      /* Set to one to notify the caller of
 105                                          * snapshot_write_next() that it may
 106                                          * need to call wait_on_bio_chain()
 107                                          */
 108 };
 109
 110 /* This macro returns the address from/to which the caller of
 111  * snapshot_read_next()/snapshot_write_next() is allowed to
 112  * read/write data after the function returns
 113  */
 114 #define data_of(handle) ((handle).buffer + (handle).buf_offset)
 115
 116 extern unsigned int snapshot_additional_pages(struct zone *zone);
 117 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
 118 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
 119 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 120 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 121
 122 /*
 123  * This structure is used to pass the values needed for the identification
 124  * of the resume swap area from a user space to the kernel via the
 125  * SNAPSHOT_SET_SWAP_AREA ioctl
 126  */
 127 struct resume_swap_area {
 128         loff_t offset;
 129         u_int32_t dev;
 130 } __attribute__((packed));
 131
 132 #define SNAPSHOT_IOC_MAGIC      '3'
 133 #define SNAPSHOT_FREEZE                 _IO(SNAPSHOT_IOC_MAGIC, 1)
 134 #define SNAPSHOT_UNFREEZE               _IO(SNAPSHOT_IOC_MAGIC, 2)
 135 #define SNAPSHOT_ATOMIC_SNAPSHOT        _IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
 136 #define SNAPSHOT_ATOMIC_RESTORE         _IO(SNAPSHOT_IOC_MAGIC, 4)
 137 #define SNAPSHOT_FREE                   _IO(SNAPSHOT_IOC_MAGIC, 5)
 138 #define SNAPSHOT_SET_IMAGE_SIZE         _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
 139 #define SNAPSHOT_AVAIL_SWAP             _IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
 140 #define SNAPSHOT_GET_SWAP_PAGE          _IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
 141 #define SNAPSHOT_FREE_SWAP_PAGES        _IO(SNAPSHOT_IOC_MAGIC, 9)
 142 #define SNAPSHOT_SET_SWAP_FILE          _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
 143 #define SNAPSHOT_S2RAM                  _IO(SNAPSHOT_IOC_MAGIC, 11)
 144 #define SNAPSHOT_PMOPS                  _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
 145 #define SNAPSHOT_SET_SWAP_AREA          _IOW(SNAPSHOT_IOC_MAGIC, 13, \
 146                                                         struct resume_swap_area)
 147 #define SNAPSHOT_IOC_MAXNR      13
 148
 149 #define PMOPS_PREPARE   1
 150 #define PMOPS_ENTER     2
 151 #define PMOPS_FINISH    3
 152
 153 /* If unset, the snapshot device cannot be open. */
 154 extern atomic_t snapshot_device_available;
 155
 156 extern sector_t alloc_swapdev_block(int swap);
 157 extern void free_all_swap_pages(int swap);
 158 extern int swsusp_swap_in_use(void);
 159
 160 extern int swsusp_check(void);
 161 extern int swsusp_shrink_memory(void);
 162 extern void swsusp_free(void);
 163 extern int swsusp_suspend(void);
 164 extern int swsusp_resume(void);
 165 extern int swsusp_read(void);
 166 extern int swsusp_write(void);
 167 extern void swsusp_close(void);
 168 extern int suspend_enter(suspend_state_t state);
 169
 170 struct timeval;
 171 extern void swsusp_show_speed(struct timeval *, struct timeval *,
 172                                 unsigned int, char *);