pagevec.h 1.7 KB

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  1. /*
  2. * include/linux/pagevec.h
  3. *
  4. * In many places it is efficient to batch an operation up against multiple
  5. * pages. A pagevec is a multipage container which is used for that.
  6. */
  7. #ifndef _LINUX_PAGEVEC_H
  8. #define _LINUX_PAGEVEC_H
  9. /* 14 pointers + two long's align the pagevec structure to a power of two */
  10. #define PAGEVEC_SIZE 14
  11. struct page;
  12. struct address_space;
  13. struct pagevec {
  14. unsigned long nr;
  15. unsigned long cold;
  16. struct page *pages[PAGEVEC_SIZE];
  17. };
  18. void __pagevec_release(struct pagevec *pvec);
  19. void __pagevec_lru_add(struct pagevec *pvec);
  20. unsigned pagevec_lookup_entries(struct pagevec *pvec,
  21. struct address_space *mapping,
  22. pgoff_t start, unsigned nr_entries,
  23. pgoff_t *indices);
  24. void pagevec_remove_exceptionals(struct pagevec *pvec);
  25. unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
  26. pgoff_t start, unsigned nr_pages);
  27. unsigned pagevec_lookup_tag(struct pagevec *pvec,
  28. struct address_space *mapping, pgoff_t *index, int tag,
  29. unsigned nr_pages);
  30. static inline void pagevec_init(struct pagevec *pvec, int cold)
  31. {
  32. pvec->nr = 0;
  33. pvec->cold = cold;
  34. }
  35. static inline void pagevec_reinit(struct pagevec *pvec)
  36. {
  37. pvec->nr = 0;
  38. }
  39. static inline unsigned pagevec_count(struct pagevec *pvec)
  40. {
  41. return pvec->nr;
  42. }
  43. static inline unsigned pagevec_space(struct pagevec *pvec)
  44. {
  45. return PAGEVEC_SIZE - pvec->nr;
  46. }
  47. /*
  48. * Add a page to a pagevec. Returns the number of slots still available.
  49. */
  50. static inline unsigned pagevec_add(struct pagevec *pvec, struct page *page)
  51. {
  52. pvec->pages[pvec->nr++] = page;
  53. return pagevec_space(pvec);
  54. }
  55. static inline void pagevec_release(struct pagevec *pvec)
  56. {
  57. if (pagevec_count(pvec))
  58. __pagevec_release(pvec);
  59. }
  60. #endif /* _LINUX_PAGEVEC_H */