pagevec.h 1.5 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(struct pagevec *pvec, struct address_space *mapping,
  21. pgoff_t start, unsigned nr_pages);
  22. unsigned pagevec_lookup_tag(struct pagevec *pvec,
  23. struct address_space *mapping, pgoff_t *index, int tag,
  24. unsigned nr_pages);
  25. static inline void pagevec_init(struct pagevec *pvec, int cold)
  26. {
  27. pvec->nr = 0;
  28. pvec->cold = cold;
  29. }
  30. static inline void pagevec_reinit(struct pagevec *pvec)
  31. {
  32. pvec->nr = 0;
  33. }
  34. static inline unsigned pagevec_count(struct pagevec *pvec)
  35. {
  36. return pvec->nr;
  37. }
  38. static inline unsigned pagevec_space(struct pagevec *pvec)
  39. {
  40. return PAGEVEC_SIZE - pvec->nr;
  41. }
  42. /*
  43. * Add a page to a pagevec. Returns the number of slots still available.
  44. */
  45. static inline unsigned pagevec_add(struct pagevec *pvec, struct page *page)
  46. {
  47. pvec->pages[pvec->nr++] = page;
  48. return pagevec_space(pvec);
  49. }
  50. static inline void pagevec_release(struct pagevec *pvec)
  51. {
  52. if (pagevec_count(pvec))
  53. __pagevec_release(pvec);
  54. }
  55. #endif /* _LINUX_PAGEVEC_H */