kernel/power/tuxonice_extent.h

   1 /*
   2  * kernel/power/tuxonice_extent.h
   3  *
   4  * Copyright (C) 2003-2007 Nigel Cunningham (nigel at suspend2 net)
   5  *
   6  * This file is released under the GPLv2.
   7  *
   8  * It contains declarations related to extents. Extents are
   9  * TuxOnIce's method of storing some of the metadata for the image.
  10  * See tuxonice_extent.c for more info.
  11  *
  12  */
  13
  14 #include "tuxonice_modules.h"
  15
  16 #ifndef EXTENT_H
  17 #define EXTENT_H
  18
  19 struct extent {
  20         unsigned long minimum, maximum;
  21         struct extent *next;
  22 };
  23
  24 struct extent_chain {
  25         int size; /* size of the chain ie sum (max-min+1) */
  26         int num_extents;
  27         struct extent *first, *last_touched;
  28 };
  29
  30 struct extent_iterate_state {
  31         struct extent_chain *chains;
  32         int num_chains;
  33         int current_chain;
  34         struct extent *current_extent;
  35         unsigned long current_offset;
  36 };
  37
  38 struct extent_iterate_saved_state {
  39         int chain_num;
  40         int extent_num;
  41         unsigned long offset;
  42 };
  43
  44 #define toi_extent_state_eof(state) ((state)->num_chains == (state)->current_chain)
  45
  46 /* Simplify iterating through all the values in an extent chain */
  47 #define toi_extent_for_each(extent_chain, extentpointer, value) \
  48 if ((extent_chain)->first) \
  49         for ((extentpointer) = (extent_chain)->first, (value) = \
  50                         (extentpointer)->minimum; \
  51              ((extentpointer) && ((extentpointer)->next || (value) <= \
  52                                  (extentpointer)->maximum)); \
  53              (((value) == (extentpointer)->maximum) ? \
  54                 ((extentpointer) = (extentpointer)->next, (value) = \
  55                  ((extentpointer) ? (extentpointer)->minimum : 0)) : \
  56                         (value)++))
  57
  58 void toi_put_extent_chain(struct extent_chain *chain);
  59 int toi_add_to_extent_chain(struct extent_chain *chain,
  60                 unsigned long minimum, unsigned long maximum);
  61 int toi_serialise_extent_chain(struct toi_module_ops *owner,
  62                 struct extent_chain *chain);
  63 int toi_load_extent_chain(struct extent_chain *chain);
  64
  65 /* swap_entry_to_extent_val & extent_val_to_swap_entry:
  66  * We are putting offset in the low bits so consecutive swap entries
  67  * make consecutive extent values */
  68 #define swap_entry_to_extent_val(swp_entry) (swp_entry.val)
  69 #define extent_val_to_swap_entry(val) (swp_entry_t) { (val) }
  70
  71 void toi_extent_state_save(struct extent_iterate_state *state,
  72                 struct extent_iterate_saved_state *saved_state);
  73 void toi_extent_state_restore(struct extent_iterate_state *state,
  74                 struct extent_iterate_saved_state *saved_state);
  75 void toi_extent_state_goto_start(struct extent_iterate_state *state);
  76 unsigned long toi_extent_state_next(struct extent_iterate_state *state);
  77 #endif