LXR linux/include/linux/pagevec.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 * include/linux/pagevec.h
   4 *
   5 * In many places it is efficient to batch an operation up against multiple
   6 * pages.  A pagevec is a multipage container which is used for that.
   7 */
   8
   9#ifndef _LINUX_PAGEVEC_H
  10#define _LINUX_PAGEVEC_H
  11
  12/* 14 pointers + two long's align the pagevec structure to a power of two */
  13#define PAGEVEC_SIZE    14
  14
  15struct page;
  16struct address_space;
  17
  18struct pagevec {
  19        unsigned long nr;
  20        unsigned long cold;
  21        struct page *pages[PAGEVEC_SIZE];
  22};
  23
  24void __pagevec_release(struct pagevec *pvec);
  25void __pagevec_lru_add(struct pagevec *pvec);
  26unsigned pagevec_lookup_entries(struct pagevec *pvec,
  27                                struct address_space *mapping,
  28                                pgoff_t start, unsigned nr_entries,
  29                                pgoff_t *indices);
  30void pagevec_remove_exceptionals(struct pagevec *pvec);
  31unsigned pagevec_lookup_range(struct pagevec *pvec,
  32                              struct address_space *mapping,
  33                              pgoff_t *start, pgoff_t end);
  34static inline unsigned pagevec_lookup(struct pagevec *pvec,
  35                                      struct address_space *mapping,
  36                                      pgoff_t *start)
  37{
  38        return pagevec_lookup_range(pvec, mapping, start, (pgoff_t)-1);
  39}
  40
  41unsigned pagevec_lookup_tag(struct pagevec *pvec,
  42                struct address_space *mapping, pgoff_t *index, int tag,
  43                unsigned nr_pages);
  44
  45static inline void pagevec_init(struct pagevec *pvec, int cold)
  46{
  47        pvec->nr = 0;
  48        pvec->cold = cold;
  49}
  50
  51static inline void pagevec_reinit(struct pagevec *pvec)
  52{
  53        pvec->nr = 0;
  54}
  55
  56static inline unsigned pagevec_count(struct pagevec *pvec)
  57{
  58        return pvec->nr;
  59}
  60
  61static inline unsigned pagevec_space(struct pagevec *pvec)
  62{
  63        return PAGEVEC_SIZE - pvec->nr;
  64}
  65
  66/*
  67 * Add a page to a pagevec.  Returns the number of slots still available.
  68 */
  69static inline unsigned pagevec_add(struct pagevec *pvec, struct page *page)
  70{
  71        pvec->pages[pvec->nr++] = page;
  72        return pagevec_space(pvec);
  73}
  74
  75static inline void pagevec_release(struct pagevec *pvec)
  76{
  77        if (pagevec_count(pvec))
  78                __pagevec_release(pvec);
  79}
  80
  81#endif /* _LINUX_PAGEVEC_H */
  82