LXR linux/include/linux/pagevec.h

   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
   8#ifndef _LINUX_PAGEVEC_H
   9#define _LINUX_PAGEVEC_H
  10
  11/* 14 pointers + two long's align the pagevec structure to a power of two */
  12#define PAGEVEC_SIZE    14
  13
  14struct page;
  15struct address_space;
  16
  17struct pagevec {
  18        unsigned long nr;
  19        unsigned long cold;
  20        struct page *pages[PAGEVEC_SIZE];
  21};
  22
  23void __pagevec_release(struct pagevec *pvec);
  24void __pagevec_release_nonlru(struct pagevec *pvec);
  25void __pagevec_free(struct pagevec *pvec);
  26void __pagevec_lru_add(struct pagevec *pvec);
  27void __pagevec_lru_add_active(struct pagevec *pvec);
  28void pagevec_strip(struct pagevec *pvec);
  29unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
  30                pgoff_t start, unsigned nr_pages);
  31unsigned pagevec_lookup_tag(struct pagevec *pvec,
  32                struct address_space *mapping, pgoff_t *index, int tag,
  33                unsigned nr_pages);
  34
  35static inline void pagevec_init(struct pagevec *pvec, int cold)
  36{
  37        pvec->nr = 0;
  38        pvec->cold = cold;
  39}
  40
  41static inline void pagevec_reinit(struct pagevec *pvec)
  42{
  43        pvec->nr = 0;
  44}
  45
  46static inline unsigned pagevec_count(struct pagevec *pvec)
  47{
  48        return pvec->nr;
  49}
  50
  51static inline unsigned pagevec_space(struct pagevec *pvec)
  52{
  53        return PAGEVEC_SIZE - pvec->nr;
  54}
  55
  56/*
  57 * Add a page to a pagevec.  Returns the number of slots still available.
  58 */
  59static inline unsigned pagevec_add(struct pagevec *pvec, struct page *page)
  60{
  61        pvec->pages[pvec->nr++] = page;
  62        return pagevec_space(pvec);
  63}
  64
  65
  66static inline void pagevec_release(struct pagevec *pvec)
  67{
  68        if (pagevec_count(pvec))
  69                __pagevec_release(pvec);
  70}
  71
  72static inline void pagevec_release_nonlru(struct pagevec *pvec)
  73{
  74        if (pagevec_count(pvec))
  75                __pagevec_release_nonlru(pvec);
  76}
  77
  78static inline void pagevec_free(struct pagevec *pvec)
  79{
  80        if (pagevec_count(pvec))
  81                __pagevec_free(pvec);
  82}
  83
  84static inline void pagevec_lru_add(struct pagevec *pvec)
  85{
  86        if (pagevec_count(pvec))
  87                __pagevec_lru_add(pvec);
  88}
  89
  90#endif /* _LINUX_PAGEVEC_H */
  91