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	/* Read I/O data */
45#define BIO_WRITE	0x02	/* Write I/O data */
46#define BIO_DELETE	0x04	/* TRIM or free blocks, i.e. mark as unused */
47#define BIO_GETATTR	0x08	/* Get GEOM attributes of object */
48#define BIO_FLUSH	0x10	/* Commit outstanding I/O now */
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	/* An error occurred processing this bio. */
55#define BIO_DONE	0x02	/* This bio is finished. */
56#define BIO_ONQUEUE	0x04	/* This bio is in a queue & not yet taken. */
57/*
58 * This bio must be executed after all previous bios in the queue have been
59 * executed, and before any successive bios can be executed.
60 */
61#define BIO_ORDERED	0x08
62#define	BIO_UNMAPPED	0x10
63#define	BIO_TRANSIENT_MAPPING	0x20
64#define	BIO_VLIST	0x40
65
66#ifdef _KERNEL
67struct disk;
68struct bio;
69struct vm_map;
70
71/* Empty classifier tag, to prevent further classification. */
72#define	BIO_NOTCLASSIFIED		(void *)(~0UL)
73
74typedef void bio_task_t(void *);
75
76/*
77 * The bio structure describes an I/O operation in the kernel.
78 */
79struct bio {
80	uint8_t	bio_cmd;		/* I/O operation. */
81	uint8_t	bio_flags;		/* General flags. */
82	uint8_t	bio_cflags;		/* Private use by the consumer. */
83	uint8_t	bio_pflags;		/* Private use by the provider. */
84	struct cdev *bio_dev;		/* Device to do I/O on. */
85	struct disk *bio_disk;		/* Valid below geom_disk.c only */
86	off_t	bio_offset;		/* Offset into file. */
87	long	bio_bcount;		/* Valid bytes in buffer. */
88	caddr_t	bio_data;		/* Memory, superblocks, indirect etc. */
89	struct vm_page **bio_ma;	/* Or unmapped. */
90	int	bio_ma_offset;		/* Offset in the first page of bio_ma. */
91	int	bio_ma_n;		/* Number of pages in bio_ma. */
92	int	bio_error;		/* Errno for BIO_ERROR. */
93	long	bio_resid;		/* Remaining I/O in bytes. */
94	void	(*bio_done)(struct bio *);
95	void	*bio_driver1;		/* Private use by the provider. */
96	void	*bio_driver2;		/* Private use by the provider. */
97	void	*bio_caller1;		/* Private use by the consumer. */
98	void	*bio_caller2;		/* Private use by the consumer. */
99	TAILQ_ENTRY(bio) bio_queue;	/* Disksort queue. */
100	const char *bio_attribute;	/* Attribute for BIO_[GS]ETATTR */
101	struct g_consumer *bio_from;	/* GEOM linkage */
102	struct g_provider *bio_to;	/* GEOM linkage */
103	off_t	bio_length;		/* Like bio_bcount */
104	off_t	bio_completed;		/* Inverse of bio_resid */
105	u_int	bio_children;		/* Number of spawned bios */
106	u_int	bio_inbed;		/* Children safely home by now */
107	struct bio *bio_parent;		/* Pointer to parent */
108	struct bintime bio_t0;		/* Time request started */
109
110	bio_task_t *bio_task;		/* Task_queue handler */
111	void	*bio_task_arg;		/* Argument to above */
112
113	void	*bio_classifier1;	/* Classifier tag. */
114	void	*bio_classifier2;	/* Classifier tag. */
115
116#ifdef DIAGNOSTIC
117	void	*_bio_caller1;
118	void	*_bio_caller2;
119	uint8_t	_bio_cflags;
120#endif
121
122	/* XXX: these go away when bio chaining is introduced */
123	daddr_t bio_pblkno;               /* physical block number */
124};
125
126struct uio;
127struct devstat;
128
129struct bio_queue_head {
130	TAILQ_HEAD(bio_queue, bio) queue;
131	off_t last_offset;
132	struct	bio *insert_point;
133};
134
135extern struct vm_map *bio_transient_map;
136extern int bio_transient_maxcnt;
137
138void biodone(struct bio *bp);
139void biofinish(struct bio *bp, struct devstat *stat, int error);
140int biowait(struct bio *bp, const char *wchan);
141
142void bioq_disksort(struct bio_queue_head *ap, struct bio *bp);
143struct bio *bioq_first(struct bio_queue_head *head);
144struct bio *bioq_takefirst(struct bio_queue_head *head);
145void bioq_flush(struct bio_queue_head *head, struct devstat *stp, int error);
146void bioq_init(struct bio_queue_head *head);
147void bioq_insert_head(struct bio_queue_head *head, struct bio *bp);
148void bioq_insert_tail(struct bio_queue_head *head, struct bio *bp);
149void bioq_remove(struct bio_queue_head *head, struct bio *bp);
150
151void bio_taskqueue(struct bio *bp, bio_task_t *fund, void *arg);
152
153int	physio(struct cdev *dev, struct uio *uio, int ioflag);
154#define physread physio
155#define physwrite physio
156
157#endif /* _KERNEL */
158
159#endif /* !_SYS_BIO_H_ */
160