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 #include <linux/xarray.h>
  13
  14 /* 15 pointers + header align the pagevec structure to a power of two */
  15 #define PAGEVEC_SIZE    15
  16
  17 struct page;
  18 struct address_space;
  19
  20 struct pagevec {
  21         unsigned char nr;
  22         bool percpu_pvec_drained;
  23         struct page *pages[PAGEVEC_SIZE];
  24 };
  25
  26 void __pagevec_release(struct pagevec *pvec);
  27 void __pagevec_lru_add(struct pagevec *pvec);
  28 unsigned pagevec_lookup_entries(struct pagevec *pvec,
  29                                 struct address_space *mapping,
  30                                 pgoff_t start, unsigned nr_entries,
  31                                 pgoff_t *indices);
  32 void pagevec_remove_exceptionals(struct pagevec *pvec);
  33 unsigned pagevec_lookup_range(struct pagevec *pvec,
  34                               struct address_space *mapping,
  35                               pgoff_t *start, pgoff_t end);
  36 static inline unsigned pagevec_lookup(struct pagevec *pvec,
  37                                       struct address_space *mapping,
  38                                       pgoff_t *start)
  39 {
  40         return pagevec_lookup_range(pvec, mapping, start, (pgoff_t)-1);
  41 }
  42
  43 unsigned pagevec_lookup_range_tag(struct pagevec *pvec,
  44                 struct address_space *mapping, pgoff_t *index, pgoff_t end,
  45                 xa_mark_t tag);
  46 unsigned pagevec_lookup_range_nr_tag(struct pagevec *pvec,
  47                 struct address_space *mapping, pgoff_t *index, pgoff_t end,
  48                 xa_mark_t tag, unsigned max_pages);
  49 static inline unsigned pagevec_lookup_tag(struct pagevec *pvec,
  50                 struct address_space *mapping, pgoff_t *index, xa_mark_t tag)
  51 {
  52         return pagevec_lookup_range_tag(pvec, mapping, index, (pgoff_t)-1, tag);
  53 }
  54
  55 static inline void pagevec_init(struct pagevec *pvec)
  56 {
  57         pvec->nr = 0;
  58         pvec->percpu_pvec_drained = false;
  59 }
  60
  61 static inline void pagevec_reinit(struct pagevec *pvec)
  62 {
  63         pvec->nr = 0;
  64 }
  65
  66 static inline unsigned pagevec_count(struct pagevec *pvec)
  67 {
  68         return pvec->nr;
  69 }
  70
  71 static inline unsigned pagevec_space(struct pagevec *pvec)
  72 {
  73         return PAGEVEC_SIZE - pvec->nr;
  74 }
  75
  76 /*
  77  * Add a page to a pagevec.  Returns the number of slots still available.
  78  */
  79 static inline unsigned pagevec_add(struct pagevec *pvec, struct page *page)
  80 {
  81         pvec->pages[pvec->nr++] = page;
  82         return pagevec_space(pvec);
  83 }
  84
  85 static inline void pagevec_release(struct pagevec *pvec)
  86 {
  87         if (pagevec_count(pvec))
  88                 __pagevec_release(pvec);
  89 }
  90
  91 #endif /* _LINUX_PAGEVEC_H */