1/*-
2 * Copyright (c) 1982, 1986, 1989, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 4. Neither the name of the University nor the names of its contributors
19 *    may be used to endorse or promote products derived from this software
20 *    without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 *
34 *	@(#)buf.h	8.9 (Berkeley) 3/30/95
35 * $FreeBSD$
36 */
37
38#ifndef _SYS_BIO_H_
39#define	_SYS_BIO_H_
40
41#include <sys/queue.h>
42
43/* bio_cmd */
44#define BIO_READ	0x01
45#define BIO_WRITE	0x02
46#define BIO_DELETE	0x04
47#define BIO_GETATTR	0x08
48#define BIO_FLUSH	0x10
49#define BIO_CMD0	0x20	/* Available for local hacks */
50#define BIO_CMD1	0x40	/* Available for local hacks */
51#define BIO_CMD2	0x80	/* Available for local hacks */
52
53/* bio_flags */
54#define BIO_ERROR	0x01
55#define BIO_DONE	0x02
56#define BIO_ONQUEUE	0x04
57#define BIO_ORDERED	0x08
58#define	BIO_UNMAPPED	0x10
59#define	BIO_TRANSIENT_MAPPING	0x20
60
61#ifdef _KERNEL
62struct disk;
63struct bio;
64struct vm_map;
65
66/* Empty classifier tag, to prevent further classification. */
67#define	BIO_NOTCLASSIFIED		(void *)(~0UL)
68
69typedef void bio_task_t(void *);
70
71/*
72 * The bio structure describes an I/O operation in the kernel.
73 */
74struct bio {
75	uint8_t	bio_cmd;		/* I/O operation. */
76	uint8_t	bio_flags;		/* General flags. */
77	uint8_t	bio_cflags;		/* Private use by the consumer. */
78	uint8_t	bio_pflags;		/* Private use by the provider. */
79	struct cdev *bio_dev;		/* Device to do I/O on. */
80	struct disk *bio_disk;		/* Valid below geom_disk.c only */
81	off_t	bio_offset;		/* Offset into file. */
82	long	bio_bcount;		/* Valid bytes in buffer. */
83	caddr_t	bio_data;		/* Memory, superblocks, indirect etc. */
84	int	bio_error;		/* Errno for BIO_ERROR. */
85	long	bio_resid;		/* Remaining I/O in bytes. */
86	void	(*bio_done)(struct bio *);
87	void	*bio_driver1;		/* Private use by the provider. */
88	void	*bio_driver2;		/* Private use by the provider. */
89	void	*bio_caller1;		/* Private use by the consumer. */
90	void	*bio_caller2;		/* Private use by the consumer. */
91	TAILQ_ENTRY(bio) bio_queue;	/* Disksort queue. */
92	const char *bio_attribute;	/* Attribute for BIO_[GS]ETATTR */
93	struct g_consumer *bio_from;	/* GEOM linkage */
94	struct g_provider *bio_to;	/* GEOM linkage */
95	off_t	bio_length;		/* Like bio_bcount */
96	off_t	bio_completed;		/* Inverse of bio_resid */
97	u_int	bio_children;		/* Number of spawned bios */
98	u_int	bio_inbed;		/* Children safely home by now */
99	struct bio *bio_parent;		/* Pointer to parent */
100	struct bintime bio_t0;		/* Time request started */
101
102	bio_task_t *bio_task;		/* Task_queue handler */
103	void	*bio_task_arg;		/* Argument to above */
104
105	void	*bio_classifier1;	/* Classifier tag. */
106	void	*bio_classifier2;	/* Classifier tag. */
107
108#ifdef DIAGNOSTIC
109	void	*_bio_caller1;
110	void	*_bio_caller2;
111	uint8_t	_bio_cflags;
112#endif
113
114	/* XXX: these go away when bio chaining is introduced */
115	daddr_t bio_pblkno;               /* physical block number */
116
117	/* Unmapped i/o.  Placed at the end in 9.x for binary compatibility. */
118	struct vm_page **bio_ma;	/* Physical page array. */
119	int	bio_ma_offset;		/* Offset in first page of bio_ma. */
120	int	bio_ma_n;		/* Number of pages in bio_ma. */
121};
122
123struct uio;
124struct devstat;
125
126struct bio_queue_head {
127	TAILQ_HEAD(bio_queue, bio) queue;
128	off_t last_offset;
129	struct	bio *insert_point;
130};
131
132extern struct vm_map *bio_transient_map;
133extern int bio_transient_maxcnt;
134
135void biodone(struct bio *bp);
136void biofinish(struct bio *bp, struct devstat *stat, int error);
137int biowait(struct bio *bp, const char *wchan);
138
139void bioq_disksort(struct bio_queue_head *ap, struct bio *bp);
140struct bio *bioq_first(struct bio_queue_head *head);
141struct bio *bioq_takefirst(struct bio_queue_head *head);
142void bioq_flush(struct bio_queue_head *head, struct devstat *stp, int error);
143void bioq_init(struct bio_queue_head *head);
144void bioq_insert_head(struct bio_queue_head *head, struct bio *bp);
145void bioq_insert_tail(struct bio_queue_head *head, struct bio *bp);
146void bioq_remove(struct bio_queue_head *head, struct bio *bp);
147
148void bio_taskqueue(struct bio *bp, bio_task_t *fund, void *arg);
149
150int	physio(struct cdev *dev, struct uio *uio, int ioflag);
151#define physread physio
152#define physwrite physio
153
154#endif /* _KERNEL */
155
156#endif /* !_SYS_BIO_H_ */
157