[linux-2.6-block.git] / include / linux / pagevec.h

/*
 * include/linux/pagevec.h
 *
 * In many places it is efficient to batch an operation up against multiple
 * pages.  A pagevec is a multipage container which is used for that.
 */

#ifndef _LINUX_PAGEVEC_H
#define _LINUX_PAGEVEC_H

/* 14 pointers + two long's align the pagevec structure to a power of two */
#define PAGEVEC_SIZE	14

struct page;
struct address_space;

struct pagevec {
	unsigned long nr;
	unsigned long cold;
	struct page *pages[PAGEVEC_SIZE];
};

void __pagevec_release(struct pagevec *pvec);
void __pagevec_lru_add(struct pagevec *pvec);
unsigned pagevec_lookup_entries(struct pagevec *pvec,
				struct address_space *mapping,
				pgoff_t start, unsigned nr_entries,
				pgoff_t *indices);
void pagevec_remove_exceptionals(struct pagevec *pvec);
unsigned pagevec_lookup(struct pagevec *pvec, struct address_space *mapping,
		pgoff_t start, unsigned nr_pages);
unsigned pagevec_lookup_tag(struct pagevec *pvec,
		struct address_space *mapping, pgoff_t *index, int tag,
		unsigned nr_pages);

static inline void pagevec_init(struct pagevec *pvec, int cold)
{
	pvec->nr = 0;
	pvec->cold = cold;
}

static inline void pagevec_reinit(struct pagevec *pvec)
{
	pvec->nr = 0;
}

static inline unsigned pagevec_count(struct pagevec *pvec)
{
	return pvec->nr;
}

static inline unsigned pagevec_space(struct pagevec *pvec)
{
	return PAGEVEC_SIZE - pvec->nr;
}

/*
 * Add a page to a pagevec.  Returns the number of slots still available.
 */
static inline unsigned pagevec_add(struct pagevec *pvec, struct page *page)
{
	pvec->pages[pvec->nr++] = page;
	return pagevec_space(pvec);
}

static inline void pagevec_release(struct pagevec *pvec)
{
	if (pagevec_count(pvec))
		__pagevec_release(pvec);
}

#endif /* _LINUX_PAGEVEC_H */
Commit	Line	Data
1da177e4 LT	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
78854014 DH	8	#ifndef _LINUX_PAGEVEC_H
	9	#define _LINUX_PAGEVEC_H
	10
1da177e4 LT	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);
a0b8cab3	24	void __pagevec_lru_add(struct pagevec *pvec);
0cd6144a JW	25	unsigned pagevec_lookup_entries(struct pagevec *pvec,
	26	struct address_space *mapping,
	27	pgoff_t start, unsigned nr_entries,
	28	pgoff_t *indices);
	29	void pagevec_remove_exceptionals(struct pagevec *pvec);
1da177e4 LT	30	unsigned pagevec_lookup(struct pagevec pvec, struct address_space mapping,
	31	pgoff_t start, unsigned nr_pages);
	32	unsigned pagevec_lookup_tag(struct pagevec *pvec,
	33	struct address_space mapping, pgoff_t index, int tag,
	34	unsigned nr_pages);
	35
	36	static inline void pagevec_init(struct pagevec *pvec, int cold)
	37	{
	38	pvec->nr = 0;
	39	pvec->cold = cold;
	40	}
	41
	42	static inline void pagevec_reinit(struct pagevec *pvec)
	43	{
	44	pvec->nr = 0;
	45	}
	46
	47	static inline unsigned pagevec_count(struct pagevec *pvec)
	48	{
	49	return pvec->nr;
	50	}
	51
	52	static inline unsigned pagevec_space(struct pagevec *pvec)
	53	{
	54	return PAGEVEC_SIZE - pvec->nr;
	55	}
	56
	57	/*
	58	* Add a page to a pagevec. Returns the number of slots still available.
	59	*/
	60	static inline unsigned pagevec_add(struct pagevec pvec, struct page page)
	61	{
	62	pvec->pages[pvec->nr++] = page;
	63	return pagevec_space(pvec);
	64	}
	65
1da177e4 LT	66	static inline void pagevec_release(struct pagevec *pvec)
	67	{
	68	if (pagevec_count(pvec))
	69	__pagevec_release(pvec);
	70	}
	71
78854014	72	#endif /* _LINUX_PAGEVEC_H */