xref: /linux-6.15/include/linux/pagevec.h (revision e756bc56)
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_lru_add(struct pagevec *pvec);
25 unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
26 		pgoff_t start, unsigned nr_pages);
27 unsigned pagevec_lookup_tag(struct pagevec *pvec,
28 		struct address_space *mapping, pgoff_t *index, int tag,
29 		unsigned nr_pages);
30 
31 static inline void pagevec_init(struct pagevec *pvec, int cold)
32 {
33 	pvec->nr = 0;
34 	pvec->cold = cold;
35 }
36 
37 static inline void pagevec_reinit(struct pagevec *pvec)
38 {
39 	pvec->nr = 0;
40 }
41 
42 static inline unsigned pagevec_count(struct pagevec *pvec)
43 {
44 	return pvec->nr;
45 }
46 
47 static inline unsigned pagevec_space(struct pagevec *pvec)
48 {
49 	return PAGEVEC_SIZE - pvec->nr;
50 }
51 
52 /*
53  * Add a page to a pagevec.  Returns the number of slots still available.
54  */
55 static inline unsigned pagevec_add(struct pagevec *pvec, struct page *page)
56 {
57 	pvec->pages[pvec->nr++] = page;
58 	return pagevec_space(pvec);
59 }
60 
61 static inline void pagevec_release(struct pagevec *pvec)
62 {
63 	if (pagevec_count(pvec))
64 		__pagevec_release(pvec);
65 }
66 
67 #endif /* _LINUX_PAGEVEC_H */
68