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 
pagevec_init(struct pagevec * pvec,int cold)33 static inline void pagevec_init(struct pagevec *pvec, int cold)
34 {
35 	pvec->nr = 0;
36 	pvec->cold = cold;
37 }
38 
pagevec_reinit(struct pagevec * pvec)39 static inline void pagevec_reinit(struct pagevec *pvec)
40 {
41 	pvec->nr = 0;
42 }
43 
pagevec_count(struct pagevec * pvec)44 static inline unsigned pagevec_count(struct pagevec *pvec)
45 {
46 	return pvec->nr;
47 }
48 
pagevec_space(struct pagevec * pvec)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  */
pagevec_add(struct pagevec * pvec,struct page * page)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 
pagevec_release(struct pagevec * pvec)64 static inline void pagevec_release(struct pagevec *pvec)
65 {
66 	if (pagevec_count(pvec))
67 		__pagevec_release(pvec);
68 }
69 
pagevec_free(struct pagevec * pvec)70 static inline void pagevec_free(struct pagevec *pvec)
71 {
72 	if (pagevec_count(pvec))
73 		__pagevec_free(pvec);
74 }
75 
__pagevec_lru_add_anon(struct pagevec * pvec)76 static inline void __pagevec_lru_add_anon(struct pagevec *pvec)
77 {
78 	____pagevec_lru_add(pvec, LRU_INACTIVE_ANON);
79 }
80 
__pagevec_lru_add_active_anon(struct pagevec * pvec)81 static inline void __pagevec_lru_add_active_anon(struct pagevec *pvec)
82 {
83 	____pagevec_lru_add(pvec, LRU_ACTIVE_ANON);
84 }
85 
__pagevec_lru_add_file(struct pagevec * pvec)86 static inline void __pagevec_lru_add_file(struct pagevec *pvec)
87 {
88 	____pagevec_lru_add(pvec, LRU_INACTIVE_FILE);
89 }
90 
__pagevec_lru_add_active_file(struct pagevec * pvec)91 static inline void __pagevec_lru_add_active_file(struct pagevec *pvec)
92 {
93 	____pagevec_lru_add(pvec, LRU_ACTIVE_FILE);
94 }
95 
pagevec_lru_add_file(struct pagevec * pvec)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 
pagevec_lru_add_anon(struct pagevec * pvec)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 */
109