extent_map.h 1.4 KB

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  1. #ifndef __EXTENTMAP__
  2. #define __EXTENTMAP__
  3. #include <linux/rbtree.h>
  4. #define EXTENT_MAP_LAST_BYTE (u64)-4
  5. #define EXTENT_MAP_HOLE (u64)-3
  6. #define EXTENT_MAP_INLINE (u64)-2
  7. #define EXTENT_MAP_DELALLOC (u64)-1
  8. /* bits for the flags field */
  9. #define EXTENT_FLAG_PINNED 0 /* this entry not yet on disk, don't free it */
  10. #define EXTENT_FLAG_COMPRESSED 1
  11. struct extent_map {
  12. struct rb_node rb_node;
  13. /* all of these are in bytes */
  14. u64 start;
  15. u64 len;
  16. u64 block_start;
  17. u64 block_len;
  18. unsigned long flags;
  19. struct block_device *bdev;
  20. atomic_t refs;
  21. int in_tree;
  22. };
  23. struct extent_map_tree {
  24. struct rb_root map;
  25. spinlock_t lock;
  26. };
  27. static inline u64 extent_map_end(struct extent_map *em)
  28. {
  29. if (em->start + em->len < em->start)
  30. return (u64)-1;
  31. return em->start + em->len;
  32. }
  33. static inline u64 extent_map_block_end(struct extent_map *em)
  34. {
  35. if (em->block_start + em->block_len < em->block_start)
  36. return (u64)-1;
  37. return em->block_start + em->block_len;
  38. }
  39. void extent_map_tree_init(struct extent_map_tree *tree, gfp_t mask);
  40. struct extent_map *lookup_extent_mapping(struct extent_map_tree *tree,
  41. u64 start, u64 len);
  42. int add_extent_mapping(struct extent_map_tree *tree,
  43. struct extent_map *em);
  44. int remove_extent_mapping(struct extent_map_tree *tree, struct extent_map *em);
  45. struct extent_map *alloc_extent_map(gfp_t mask);
  46. void free_extent_map(struct extent_map *em);
  47. int __init extent_map_init(void);
  48. void extent_map_exit(void);
  49. #endif