FreeBSD/Linux Kernel Cross Reference
sys/sys/bio.h
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: src/sys/sys/bio.h,v 1.147 2006/10/31 21:11:21 pjd Exp $
36 */
37
38 #ifndef _SYS_BIO_H_
39 #define _SYS_BIO_H_
40
41 #include <sys/queue.h>
42
43 struct disk;
44 struct bio;
45
46 typedef void bio_task_t(void *);
47
48 /*
49 * The bio structure describes an I/O operation in the kernel.
50 */
51 struct bio {
52 uint8_t bio_cmd; /* I/O operation. */
53 uint8_t bio_flags; /* General flags. */
54 uint8_t bio_cflags; /* Private use by the consumer. */
55 uint8_t bio_pflags; /* Private use by the provider. */
56 struct cdev *bio_dev; /* Device to do I/O on. */
57 struct disk *bio_disk; /* Valid below geom_disk.c only */
58 off_t bio_offset; /* Offset into file. */
59 long bio_bcount; /* Valid bytes in buffer. */
60 caddr_t bio_data; /* Memory, superblocks, indirect etc. */
61 int bio_error; /* Errno for BIO_ERROR. */
62 long bio_resid; /* Remaining I/O in bytes. */
63 void (*bio_done)(struct bio *);
64 void *bio_driver1; /* Private use by the provider. */
65 void *bio_driver2; /* Private use by the provider. */
66 void *bio_caller1; /* Private use by the consumer. */
67 void *bio_caller2; /* Private use by the consumer. */
68 TAILQ_ENTRY(bio) bio_queue; /* Disksort queue. */
69 const char *bio_attribute; /* Attribute for BIO_[GS]ETATTR */
70 struct g_consumer *bio_from; /* GEOM linkage */
71 struct g_provider *bio_to; /* GEOM linkage */
72 off_t bio_length; /* Like bio_bcount */
73 off_t bio_completed; /* Inverse of bio_resid */
74 u_int bio_children; /* Number of spawned bios */
75 u_int bio_inbed; /* Children safely home by now */
76 struct bio *bio_parent; /* Pointer to parent */
77 struct bintime bio_t0; /* Time request started */
78
79 bio_task_t *bio_task; /* Task_queue handler */
80 void *bio_task_arg; /* Argument to above */
81 #ifdef DIAGNOSTIC
82 void *_bio_caller1;
83 void *_bio_caller2;
84 uint8_t _bio_cflags;
85 #endif
86
87 /* XXX: these go away when bio chaining is introduced */
88 daddr_t bio_pblkno; /* physical block number */
89 };
90
91 /* bio_cmd */
92 #define BIO_READ 0x01
93 #define BIO_WRITE 0x02
94 #define BIO_DELETE 0x04
95 #define BIO_GETATTR 0x08
96 #define BIO_FLUSH 0x10
97 #define BIO_CMD0 0x20 /* Available for local hacks */
98 #define BIO_CMD1 0x40 /* Available for local hacks */
99 #define BIO_CMD2 0x80 /* Available for local hacks */
100
101 /* bio_flags */
102 #define BIO_ERROR 0x01
103 #define BIO_DONE 0x02
104 #define BIO_ONQUEUE 0x04
105
106 #ifdef _KERNEL
107
108 struct uio;
109 struct devstat;
110
111 struct bio_queue_head {
112 TAILQ_HEAD(bio_queue, bio) queue;
113 off_t last_offset;
114 struct bio *insert_point;
115 };
116
117 void biodone(struct bio *bp);
118 void biofinish(struct bio *bp, struct devstat *stat, int error);
119 int biowait(struct bio *bp, const char *wchan);
120
121 void bioq_disksort(struct bio_queue_head *ap, struct bio *bp);
122 struct bio *bioq_first(struct bio_queue_head *head);
123 struct bio *bioq_takefirst(struct bio_queue_head *head);
124 void bioq_flush(struct bio_queue_head *head, struct devstat *stp, int error);
125 void bioq_init(struct bio_queue_head *head);
126 void bioq_insert_head(struct bio_queue_head *head, struct bio *bp);
127 void bioq_insert_tail(struct bio_queue_head *head, struct bio *bp);
128 void bioq_remove(struct bio_queue_head *head, struct bio *bp);
129
130 void bio_taskqueue(struct bio *bp, bio_task_t *fund, void *arg);
131
132 int physio(struct cdev *dev, struct uio *uio, int ioflag);
133 #define physread physio
134 #define physwrite physio
135
136 #endif /* _KERNEL */
137
138 #endif /* !_SYS_BIO_H_ */
139
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