[deliverable/linux.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(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);
1da177e4 LT	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
1da177e4 LT	61	static inline void pagevec_release(struct pagevec *pvec)
	62	{
	63	if (pagevec_count(pvec))
	64	__pagevec_release(pvec);
	65	}
	66
78854014	67	#endif /* _LINUX_PAGEVEC_H */