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 /* kernel/power/disk.c */
  29 extern int hibernation_snapshot(int platform_mode);
  30 extern int hibernation_restore(int platform_mode);
  31 extern int hibernation_platform_enter(void);
  32 #endif
  33
  34 extern int pfn_is_nosave(unsigned long);
  35
  36 extern struct mutex pm_mutex;
  37
  38 #define power_attr(_name) \
  39 static struct subsys_attribute _name##_attr = { \
  40         .attr   = {                             \
  41                 .name = __stringify(_name),     \
  42                 .mode = 0644,                   \
  43         },                                      \
  44         .show   = _name##_show,                 \
  45         .store  = _name##_store,                \
  46 }
  47
  48 extern struct kset power_subsys;
  49
  50 /* Preferred image size in bytes (default 500 MB) */
  51 extern unsigned long image_size;
  52 extern int in_suspend;
  53 extern dev_t swsusp_resume_device;
  54 extern sector_t swsusp_resume_block;
  55
  56 extern asmlinkage int swsusp_arch_suspend(void);
  57 extern asmlinkage int swsusp_arch_resume(void);
  58
  59 extern int create_basic_memory_bitmaps(void);
  60 extern void free_basic_memory_bitmaps(void);
  61 extern unsigned int count_data_pages(void);
  62
  63 /**
  64  *      Auxiliary structure used for reading the snapshot image data and
  65  *      metadata from and writing them to the list of page backup entries
  66  *      (PBEs) which is the main data structure of swsusp.
  67  *
  68  *      Using struct snapshot_handle we can transfer the image, including its
  69  *      metadata, as a continuous sequence of bytes with the help of
  70  *      snapshot_read_next() and snapshot_write_next().
  71  *
  72  *      The code that writes the image to a storage or transfers it to
  73  *      the user land is required to use snapshot_read_next() for this
  74  *      purpose and it should not make any assumptions regarding the internal
  75  *      structure of the image.  Similarly, the code that reads the image from
  76  *      a storage or transfers it from the user land is required to use
  77  *      snapshot_write_next().
  78  *
  79  *      This may allow us to change the internal structure of the image
  80  *      in the future with considerably less effort.
  81  */
  82
  83 struct snapshot_handle {
  84         loff_t          offset; /* number of the last byte ready for reading
  85                                  * or writing in the sequence
  86                                  */
  87         unsigned int    cur;    /* number of the block of PAGE_SIZE bytes the
  88                                  * next operation will refer to (ie. current)
  89                                  */
  90         unsigned int    cur_offset;     /* offset with respect to the current
  91                                          * block (for the next operation)
  92                                          */
  93         unsigned int    prev;   /* number of the block of PAGE_SIZE bytes that
  94                                  * was the current one previously
  95                                  */
  96         void            *buffer;        /* address of the block to read from
  97                                          * or write to
  98                                          */
  99         unsigned int    buf_offset;     /* location to read from or write to,
 100                                          * given as a displacement from 'buffer'
 101                                          */
 102         int             sync_read;      /* Set to one to notify the caller of
 103                                          * snapshot_write_next() that it may
 104                                          * need to call wait_on_bio_chain()
 105                                          */
 106 };
 107
 108 /* This macro returns the address from/to which the caller of
 109  * snapshot_read_next()/snapshot_write_next() is allowed to
 110  * read/write data after the function returns
 111  */
 112 #define data_of(handle) ((handle).buffer + (handle).buf_offset)
 113
 114 extern unsigned int snapshot_additional_pages(struct zone *zone);
 115 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
 116 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
 117 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 118 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 119
 120 /*
 121  * This structure is used to pass the values needed for the identification
 122  * of the resume swap area from a user space to the kernel via the
 123  * SNAPSHOT_SET_SWAP_AREA ioctl
 124  */
 125 struct resume_swap_area {
 126         loff_t offset;
 127         u_int32_t dev;
 128 } __attribute__((packed));
 129
 130 #define SNAPSHOT_IOC_MAGIC      '3'
 131 #define SNAPSHOT_FREEZE                 _IO(SNAPSHOT_IOC_MAGIC, 1)
 132 #define SNAPSHOT_UNFREEZE               _IO(SNAPSHOT_IOC_MAGIC, 2)
 133 #define SNAPSHOT_ATOMIC_SNAPSHOT        _IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
 134 #define SNAPSHOT_ATOMIC_RESTORE         _IO(SNAPSHOT_IOC_MAGIC, 4)
 135 #define SNAPSHOT_FREE                   _IO(SNAPSHOT_IOC_MAGIC, 5)
 136 #define SNAPSHOT_SET_IMAGE_SIZE         _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
 137 #define SNAPSHOT_AVAIL_SWAP             _IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
 138 #define SNAPSHOT_GET_SWAP_PAGE          _IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
 139 #define SNAPSHOT_FREE_SWAP_PAGES        _IO(SNAPSHOT_IOC_MAGIC, 9)
 140 #define SNAPSHOT_SET_SWAP_FILE          _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
 141 #define SNAPSHOT_S2RAM                  _IO(SNAPSHOT_IOC_MAGIC, 11)
 142 #define SNAPSHOT_PMOPS                  _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
 143 #define SNAPSHOT_SET_SWAP_AREA          _IOW(SNAPSHOT_IOC_MAGIC, 13, \
 144                                                         struct resume_swap_area)
 145 #define SNAPSHOT_IOC_MAXNR      13
 146
 147 #define PMOPS_PREPARE   1
 148 #define PMOPS_ENTER     2
 149 #define PMOPS_FINISH    3
 150
 151 /* If unset, the snapshot device cannot be open. */
 152 extern atomic_t snapshot_device_available;
 153
 154 extern sector_t alloc_swapdev_block(int swap);
 155 extern void free_all_swap_pages(int swap);
 156 extern int swsusp_swap_in_use(void);
 157
 158 /*
 159  * Flags that can be passed from the hibernatig hernel to the "boot" kernel in
 160  * the image header.
 161  */
 162 #define SF_PLATFORM_MODE        1
 163
 164 /* kernel/power/disk.c */
 165 extern int swsusp_check(void);
 166 extern int swsusp_shrink_memory(void);
 167 extern void swsusp_free(void);
 168 extern int swsusp_suspend(void);
 169 extern int swsusp_resume(void);
 170 extern int swsusp_read(unsigned int *flags_p);
 171 extern int swsusp_write(unsigned int flags);
 172 extern void swsusp_close(void);
 173 extern int suspend_enter(suspend_state_t state);
 174
 175 struct timeval;
 176 /* kernel/power/swsusp.c */
 177 extern void swsusp_show_speed(struct timeval *, struct timeval *,
 178                                 unsigned int, char *);
 179
 180 /* kernel/power/main.c */
 181 extern struct blocking_notifier_head pm_chain_head;
 182
 183 static inline int pm_notifier_call_chain(unsigned long val)
 184 {
 185         return (blocking_notifier_call_chain(&pm_chain_head, val, NULL)
 186                         == NOTIFY_BAD) ? -EINVAL : 0;
 187 }