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 void pagevec_remove_exceptionals(struct pagevec *pvec);
  29 unsigned pagevec_lookup_range(struct pagevec *pvec,
  30                               struct address_space *mapping,
  31                               pgoff_t *start, pgoff_t end);
  32 static inline unsigned pagevec_lookup(struct pagevec *pvec,
  33                                       struct address_space *mapping,
  34                                       pgoff_t *start)
  35 {
  36         return pagevec_lookup_range(pvec, mapping, start, (pgoff_t)-1);
  37 }
  38
  39 unsigned pagevec_lookup_range_tag(struct pagevec *pvec,
  40                 struct address_space *mapping, pgoff_t *index, pgoff_t end,
  41                 xa_mark_t tag);
  42 static inline unsigned pagevec_lookup_tag(struct pagevec *pvec,
  43                 struct address_space *mapping, pgoff_t *index, xa_mark_t tag)
  44 {
  45         return pagevec_lookup_range_tag(pvec, mapping, index, (pgoff_t)-1, tag);
  46 }
  47
  48 static inline void pagevec_init(struct pagevec *pvec)
  49 {
  50         pvec->nr = 0;
  51         pvec->percpu_pvec_drained = false;
  52 }
  53
  54 static inline void pagevec_reinit(struct pagevec *pvec)
  55 {
  56         pvec->nr = 0;
  57 }
  58
  59 static inline unsigned pagevec_count(struct pagevec *pvec)
  60 {
  61         return pvec->nr;
  62 }
  63
  64 static inline unsigned pagevec_space(struct pagevec *pvec)
  65 {
  66         return PAGEVEC_SIZE - pvec->nr;
  67 }
  68
  69 /*
  70  * Add a page to a pagevec.  Returns the number of slots still available.
  71  */
  72 static inline unsigned pagevec_add(struct pagevec *pvec, struct page *page)
  73 {
  74         pvec->pages[pvec->nr++] = page;
  75         return pagevec_space(pvec);
  76 }
  77
  78 static inline void pagevec_release(struct pagevec *pvec)
  79 {
  80         if (pagevec_count(pvec))
  81                 __pagevec_release(pvec);
  82 }
  83
  84 #endif /* _LINUX_PAGEVEC_H */