kernel/power/power.h

   1 /*
   2  * Copyright (C) 2004-2007 Nigel Cunningham (nigel at suspend2 net)
   3  */
   4
   5 #include <linux/suspend.h>
   6 #include <linux/utsname.h>
   7 #include "tuxonice.h"
   8 #include "tuxonice_builtin.h"
   9
  10 struct swsusp_info {
  11         struct new_utsname      uts;
  12         u32                     version_code;
  13         unsigned long           num_physpages;
  14         int                     cpus;
  15         unsigned long           image_pages;
  16         unsigned long           pages;
  17         unsigned long           size;
  18 } __attribute__((aligned(PAGE_SIZE)));
  19
  20
  21
  22 #ifdef CONFIG_SOFTWARE_SUSPEND
  23 extern char resume_file[256];
  24 /*
  25  * Keep some memory free so that I/O operations can succeed without paging
  26  * [Might this be more than 4 MB?]
  27  */
  28 #define PAGES_FOR_IO    ((4096 * 1024) >> PAGE_SHIFT)
  29 /*
  30  * Keep 1 MB of memory free so that device drivers can allocate some pages in
  31  * their .suspend() routines without breaking the suspend to disk.
  32  */
  33 #define SPARE_PAGES     ((1024 * 1024) >> PAGE_SHIFT)
  34
  35 extern struct hibernation_ops *hibernation_ops;
  36 #endif
  37
  38 extern int pfn_is_nosave(unsigned long);
  39
  40 extern struct mutex pm_mutex;
  41
  42 #define power_attr(_name) \
  43 static struct subsys_attribute _name##_attr = { \
  44         .attr   = {                             \
  45                 .name = __stringify(_name),     \
  46                 .mode = 0644,                   \
  47         },                                      \
  48         .show   = _name##_show,                 \
  49         .store  = _name##_store,                \
  50 }
  51
  52 extern struct kset power_subsys;
  53
  54 extern struct pbe *restore_pblist;
  55
  56 /* Preferred image size in bytes (default 500 MB) */
  57 extern unsigned long image_size;
  58 extern int in_suspend;
  59 extern dev_t swsusp_resume_device;
  60 extern sector_t swsusp_resume_block;
  61
  62 extern asmlinkage int swsusp_arch_suspend(void);
  63 extern asmlinkage int swsusp_arch_resume(void);
  64
  65 extern int create_basic_memory_bitmaps(void);
  66 extern void free_basic_memory_bitmaps(void);
  67 extern unsigned int count_data_pages(void);
  68
  69 /**
  70  *      Auxiliary structure used for reading the snapshot image data and
  71  *      metadata from and writing them to the list of page backup entries
  72  *      (PBEs) which is the main data structure of swsusp.
  73  *
  74  *      Using struct snapshot_handle we can transfer the image, including its
  75  *      metadata, as a continuous sequence of bytes with the help of
  76  *      snapshot_read_next() and snapshot_write_next().
  77  *
  78  *      The code that writes the image to a storage or transfers it to
  79  *      the user land is required to use snapshot_read_next() for this
  80  *      purpose and it should not make any assumptions regarding the internal
  81  *      structure of the image.  Similarly, the code that reads the image from
  82  *      a storage or transfers it from the user land is required to use
  83  *      snapshot_write_next().
  84  *
  85  *      This may allow us to change the internal structure of the image
  86  *      in the future with considerably less effort.
  87  */
  88
  89 struct snapshot_handle {
  90         loff_t          offset; /* number of the last byte ready for reading
  91                                  * or writing in the sequence
  92                                  */
  93         unsigned int    cur;    /* number of the block of PAGE_SIZE bytes the
  94                                  * next operation will refer to (ie. current)
  95                                  */
  96         unsigned int    cur_offset;     /* offset with respect to the current
  97                                          * block (for the next operation)
  98                                          */
  99         unsigned int    prev;   /* number of the block of PAGE_SIZE bytes that
 100                                  * was the current one previously
 101                                  */
 102         void            *buffer;        /* address of the block to read from
 103                                          * or write to
 104                                          */
 105         unsigned int    buf_offset;     /* location to read from or write to,
 106                                          * given as a displacement from 'buffer'
 107                                          */
 108         int             sync_read;      /* Set to one to notify the caller of
 109                                          * snapshot_write_next() that it may
 110                                          * need to call wait_on_bio_chain()
 111                                          */
 112 };
 113
 114 /* This macro returns the address from/to which the caller of
 115  * snapshot_read_next()/snapshot_write_next() is allowed to
 116  * read/write data after the function returns
 117  */
 118 #define data_of(handle) ((handle).buffer + (handle).buf_offset)
 119
 120 extern unsigned int snapshot_additional_pages(struct zone *zone);
 121 extern int snapshot_read_next(struct snapshot_handle *handle, size_t count);
 122 extern int snapshot_write_next(struct snapshot_handle *handle, size_t count);
 123 extern void snapshot_write_finalize(struct snapshot_handle *handle);
 124 extern int snapshot_image_loaded(struct snapshot_handle *handle);
 125
 126 /*
 127  * This structure is used to pass the values needed for the identification
 128  * of the resume swap area from a user space to the kernel via the
 129  * SNAPSHOT_SET_SWAP_AREA ioctl
 130  */
 131 struct resume_swap_area {
 132         loff_t offset;
 133         u_int32_t dev;
 134 } __attribute__((packed));
 135
 136 #define SNAPSHOT_IOC_MAGIC      '3'
 137 #define SNAPSHOT_FREEZE                 _IO(SNAPSHOT_IOC_MAGIC, 1)
 138 #define SNAPSHOT_UNFREEZE               _IO(SNAPSHOT_IOC_MAGIC, 2)
 139 #define SNAPSHOT_ATOMIC_SNAPSHOT        _IOW(SNAPSHOT_IOC_MAGIC, 3, void *)
 140 #define SNAPSHOT_ATOMIC_RESTORE         _IO(SNAPSHOT_IOC_MAGIC, 4)
 141 #define SNAPSHOT_FREE                   _IO(SNAPSHOT_IOC_MAGIC, 5)
 142 #define SNAPSHOT_SET_IMAGE_SIZE         _IOW(SNAPSHOT_IOC_MAGIC, 6, unsigned long)
 143 #define SNAPSHOT_AVAIL_SWAP             _IOR(SNAPSHOT_IOC_MAGIC, 7, void *)
 144 #define SNAPSHOT_GET_SWAP_PAGE          _IOR(SNAPSHOT_IOC_MAGIC, 8, void *)
 145 #define SNAPSHOT_FREE_SWAP_PAGES        _IO(SNAPSHOT_IOC_MAGIC, 9)
 146 #define SNAPSHOT_SET_SWAP_FILE          _IOW(SNAPSHOT_IOC_MAGIC, 10, unsigned int)
 147 #define SNAPSHOT_S2RAM                  _IO(SNAPSHOT_IOC_MAGIC, 11)
 148 #define SNAPSHOT_PMOPS                  _IOW(SNAPSHOT_IOC_MAGIC, 12, unsigned int)
 149 #define SNAPSHOT_SET_SWAP_AREA          _IOW(SNAPSHOT_IOC_MAGIC, 13, \
 150                                                         struct resume_swap_area)
 151 #define SNAPSHOT_IOC_MAXNR      13
 152
 153 #define PMOPS_PREPARE   1
 154 #define PMOPS_ENTER     2
 155 #define PMOPS_FINISH    3
 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 extern int swsusp_check(void);
 165 extern int swsusp_shrink_memory(void);
 166 extern void swsusp_free(void);
 167 extern int swsusp_suspend(void);
 168 extern int swsusp_resume(void);
 169 extern int swsusp_read(void);
 170 extern int swsusp_write(void);
 171 extern void swsusp_close(void);
 172 extern int suspend_enter(suspend_state_t state);
 173
 174 struct timeval;
 175 extern void swsusp_show_speed(struct timeval *, struct timeval *,
 176                                 unsigned int, char *);
 177 extern struct page *saveable_page(unsigned long pfn);
 178 #ifdef CONFIG_HIGHMEM
 179 extern struct page *saveable_highmem_page(unsigned long pfn);
 180 #else
 181 static inline void *saveable_highmem_page(unsigned long pfn) { return NULL; }
 182 #endif
 183
 184 #define PBES_PER_PAGE (PAGE_SIZE / sizeof(struct pbe))