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
  14 struct page;
  15 struct address_space;
  16
  17 struct pagevec {
  18         unsigned long nr;
  19         unsigned long cold;
  20         struct page *pages[PAGEVEC_SIZE];
  21 };
  22
  23 void __pagevec_release(struct pagevec *pvec);
  24 void __pagevec_free(struct pagevec *pvec);
  25 void ____pagevec_lru_add(struct pagevec *pvec, enum lru_list lru);
  26 void pagevec_strip(struct pagevec *pvec);
  27 unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
  28                 pgoff_t start, unsigned nr_pages);
  29 unsigned pagevec_lookup_tag(struct pagevec *pvec,
  30                 struct address_space *mapping, pgoff_t *index, int tag,
  31                 unsigned nr_pages);
  32
  33 static inline void pagevec_init(struct pagevec *pvec, int cold)
  34 {
  35         pvec->nr = 0;
  36         pvec->cold = cold;
  37 }
  38
  39 static inline void pagevec_reinit(struct pagevec *pvec)
  40 {
  41         pvec->nr = 0;
  42 }
  43
  44 static inline unsigned pagevec_count(struct pagevec *pvec)
  45 {
  46         return pvec->nr;
  47 }
  48
  49 static inline unsigned pagevec_space(struct pagevec *pvec)
  50 {
  51         return PAGEVEC_SIZE - pvec->nr;
  52 }
  53
  54 /*
  55  * Add a page to a pagevec.  Returns the number of slots still available.
  56  */
  57 static inline unsigned pagevec_add(struct pagevec *pvec, struct page *page)
  58 {
  59         pvec->pages[pvec->nr++] = page;
  60         return pagevec_space(pvec);
  61 }
  62
  63
  64 static inline void pagevec_release(struct pagevec *pvec)
  65 {
  66         if (pagevec_count(pvec))
  67                 __pagevec_release(pvec);
  68 }
  69
  70 static inline void pagevec_free(struct pagevec *pvec)
  71 {
  72         if (pagevec_count(pvec))
  73                 __pagevec_free(pvec);
  74 }
  75
  76 static inline void __pagevec_lru_add_anon(struct pagevec *pvec)
  77 {
  78         ____pagevec_lru_add(pvec, LRU_INACTIVE_ANON);
  79 }
  80
  81 static inline void __pagevec_lru_add_active_anon(struct pagevec *pvec)
  82 {
  83         ____pagevec_lru_add(pvec, LRU_ACTIVE_ANON);
  84 }
  85
  86 static inline void __pagevec_lru_add_file(struct pagevec *pvec)
  87 {
  88         ____pagevec_lru_add(pvec, LRU_INACTIVE_FILE);
  89 }
  90
  91 static inline void __pagevec_lru_add_active_file(struct pagevec *pvec)
  92 {
  93         ____pagevec_lru_add(pvec, LRU_ACTIVE_FILE);
  94 }
  95
  96 static inline void pagevec_lru_add_file(struct pagevec *pvec)
  97 {
  98         if (pagevec_count(pvec))
  99                 __pagevec_lru_add_file(pvec);
 100 }
 101
 102 static inline void pagevec_lru_add_anon(struct pagevec *pvec)
 103 {
 104         if (pagevec_count(pvec))
 105                 __pagevec_lru_add_anon(pvec);
 106 }
 107
 108 #endif /* _LINUX_PAGEVEC_H */