[linux-2.6-block.git] / drivers / md / dm-bio-list.h

/*
 * Copyright (C) 2004 Red Hat UK Ltd.
 *
 * This file is released under the GPL.
 */

#ifndef DM_BIO_LIST_H
#define DM_BIO_LIST_H

#include <linux/bio.h>

#ifdef CONFIG_BLOCK

struct bio_list {
	struct bio *head;
	struct bio *tail;
};

static inline int bio_list_empty(const struct bio_list *bl)
{
	return bl->head == NULL;
}

static inline void bio_list_init(struct bio_list *bl)
{
	bl->head = bl->tail = NULL;
}

#define bio_list_for_each(bio, bl) \
	for (bio = (bl)->head; bio; bio = bio->bi_next)

static inline unsigned bio_list_size(const struct bio_list *bl)
{
	unsigned sz = 0;
	struct bio *bio;

	bio_list_for_each(bio, bl)
		sz++;

	return sz;
}

static inline void bio_list_add(struct bio_list *bl, struct bio *bio)
{
	bio->bi_next = NULL;

	if (bl->tail)
		bl->tail->bi_next = bio;
	else
		bl->head = bio;

	bl->tail = bio;
}

static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2)
{
	if (!bl2->head)
		return;

	if (bl->tail)
		bl->tail->bi_next = bl2->head;
	else
		bl->head = bl2->head;

	bl->tail = bl2->tail;
}

static inline void bio_list_merge_head(struct bio_list *bl,
				       struct bio_list *bl2)
{
	if (!bl2->head)
		return;

	if (bl->head)
		bl2->tail->bi_next = bl->head;
	else
		bl->tail = bl2->tail;

	bl->head = bl2->head;
}

static inline struct bio *bio_list_pop(struct bio_list *bl)
{
	struct bio *bio = bl->head;

	if (bio) {
		bl->head = bl->head->bi_next;
		if (!bl->head)
			bl->tail = NULL;

		bio->bi_next = NULL;
	}

	return bio;
}

static inline struct bio *bio_list_get(struct bio_list *bl)
{
	struct bio *bio = bl->head;

	bl->head = bl->tail = NULL;

	return bio;
}

#endif /* CONFIG_BLOCK */
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Copyright (C) 2004 Red Hat UK Ltd.
	3	*
	4	* This file is released under the GPL.
	5	*/
	6
	7	#ifndef DM_BIO_LIST_H
	8	#define DM_BIO_LIST_H
	9
	10	#include <linux/bio.h>
	11
2123a09f	12	#ifdef CONFIG_BLOCK
2123a09f	13
1da177e4 LT	14	struct bio_list {
	15	struct bio *head;
	16	struct bio *tail;
	17	};
	18
0ba69934 HM	19	static inline int bio_list_empty(const struct bio_list *bl)
	20	{
	21	return bl->head == NULL;
	22	}
	23
1da177e4 LT	24	static inline void bio_list_init(struct bio_list *bl)
	25	{
	26	bl->head = bl->tail = NULL;
	27	}
	28
0ba69934	29	#define bio_list_for_each(bio, bl) \
79e15ae4	30	for (bio = (bl)->head; bio; bio = bio->bi_next)
0ba69934 HM	31
	32	static inline unsigned bio_list_size(const struct bio_list *bl)
	33	{
	34	unsigned sz = 0;
	35	struct bio *bio;
	36
	37	bio_list_for_each(bio, bl)
	38	sz++;
	39
	40	return sz;
	41	}
	42
1da177e4 LT	43	static inline void bio_list_add(struct bio_list bl, struct bio bio)
	44	{
	45	bio->bi_next = NULL;
	46
	47	if (bl->tail)
	48	bl->tail->bi_next = bio;
	49	else
	50	bl->head = bio;
	51
	52	bl->tail = bio;
	53	}
	54
	55	static inline void bio_list_merge(struct bio_list bl, struct bio_list bl2)
	56	{
233886dd	57	if (!bl2->head)
	58	return;
	59
1da177e4 LT	60	if (bl->tail)
	61	bl->tail->bi_next = bl2->head;
	62	else
	63	bl->head = bl2->head;
	64
	65	bl->tail = bl2->tail;
	66	}
	67
2e93ccc1 KU	68	static inline void bio_list_merge_head(struct bio_list *bl,
	69	struct bio_list *bl2)
	70	{
	71	if (!bl2->head)
	72	return;
	73
	74	if (bl->head)
	75	bl2->tail->bi_next = bl->head;
	76	else
	77	bl->tail = bl2->tail;
	78
	79	bl->head = bl2->head;
	80	}
	81
1da177e4 LT	82	static inline struct bio bio_list_pop(struct bio_list bl)
	83	{
	84	struct bio *bio = bl->head;
	85
	86	if (bio) {
	87	bl->head = bl->head->bi_next;
	88	if (!bl->head)
	89	bl->tail = NULL;
	90
	91	bio->bi_next = NULL;
	92	}
	93
	94	return bio;
	95	}
	96
	97	static inline struct bio bio_list_get(struct bio_list bl)
	98	{
	99	struct bio *bio = bl->head;
	100
	101	bl->head = bl->tail = NULL;
	102
	103	return bio;
	104	}
	105
2123a09f	106	#endif /* CONFIG_BLOCK */
1da177e4	107	#endif