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