xref: /freebsd/sys/sys/bio.h (revision fd630ae93634b3c7410a390c57408685caf8d937)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1982, 1986, 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  * (c) UNIX System Laboratories, Inc.
7  * All or some portions of this file are derived from material licensed
8  * to the University of California by American Telephone and Telegraph
9  * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10  * the permission of UNIX System Laboratories, Inc.
11  *
12  * Redistribution and use in source and binary forms, with or without
13  * modification, are permitted provided that the following conditions
14  * are met:
15  * 1. Redistributions of source code must retain the above copyright
16  *    notice, this list of conditions and the following disclaimer.
17  * 2. Redistributions in binary form must reproduce the above copyright
18  *    notice, this list of conditions and the following disclaimer in the
19  *    documentation and/or other materials provided with the distribution.
20  * 3. Neither the name of the University nor the names of its contributors
21  *    may be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #ifndef _SYS_BIO_H_
38 #define	_SYS_BIO_H_
39 
40 #include <sys/queue.h>
41 #include <sys/disk_zone.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	0x03	/* TRIM or free blocks, i.e. mark as unused */
47 #define BIO_GETATTR	0x04	/* Get GEOM attributes of object */
48 #define BIO_FLUSH	0x05	/* Commit outstanding I/O now */
49 #define BIO_CMD0	0x06	/* Available for local hacks */
50 #define BIO_CMD1	0x07	/* Available for local hacks */
51 #define BIO_CMD2	0x08	/* Available for local hacks */
52 #define BIO_ZONE	0x09	/* Zone command */
53 #define BIO_SPEEDUP	0x0a	/* Upper layers face shortage */
54 
55 /* bio_flags */
56 #define BIO_ERROR	0x01	/* An error occurred processing this bio. */
57 #define BIO_DONE	0x02	/* This bio is finished. */
58 #define BIO_ONQUEUE	0x04	/* This bio is in a queue & not yet taken. */
59 /*
60  * This bio must be executed after all previous bios in the queue have been
61  * executed, and before any successive bios can be executed.
62  */
63 #define BIO_ORDERED	0x08
64 #define	BIO_UNMAPPED	0x10
65 #define	BIO_TRANSIENT_MAPPING	0x20
66 #define	BIO_VLIST	0x40
67 #define	BIO_SWAP	0x200	/* Swap-related I/O */
68 #define BIO_SPEEDUP_WRITE	0x4000	/* Resource shortage at upper layers */
69 #define BIO_SPEEDUP_TRIM	0x8000	/* Resource shortage at upper layers */
70 
71 #define	PRINT_BIO_FLAGS "\20\20speedup_trim\17speedup_write\12swap\7vlist\6transient_mapping\5unmapped" \
72 	"\4ordered\3onqueue\2done\1error"
73 
74 
75 #ifdef _KERNEL
76 struct disk;
77 struct bio;
78 
79 typedef void bio_task_t(void *);
80 
81 /*
82  * The bio structure describes an I/O operation in the kernel.
83  */
84 struct bio {
85 	uint16_t bio_cmd;		/* I/O operation. */
86 	uint16_t bio_flags;		/* General flags. */
87 	uint16_t bio_cflags;		/* Private use by the consumer. */
88 	uint16_t bio_pflags;		/* Private use by the provider. */
89 	struct cdev *bio_dev;		/* Device to do I/O on. */
90 	struct disk *bio_disk;		/* Valid below geom_disk.c only */
91 	off_t	bio_offset;		/* Offset into file. */
92 	long	bio_bcount;		/* Valid bytes in buffer. */
93 	caddr_t	bio_data;		/* Memory, superblocks, indirect etc. */
94 	struct vm_page **bio_ma;	/* Or unmapped. */
95 	int	bio_ma_offset;		/* Offset in the first page of bio_ma. */
96 	int	bio_ma_n;		/* Number of pages in bio_ma. */
97 	int	bio_error;		/* Errno for BIO_ERROR. */
98 	long	bio_resid;		/* Remaining I/O in bytes. */
99 	void	(*bio_done)(struct bio *);
100 	void	*bio_driver1;		/* Private use by the provider. */
101 	void	*bio_driver2;		/* Private use by the provider. */
102 	void	*bio_caller1;		/* Private use by the consumer. */
103 	void	*bio_caller2;		/* Private use by the consumer. */
104 	TAILQ_ENTRY(bio) bio_queue;	/* Disksort queue. */
105 	const char *bio_attribute;	/* Attribute for BIO_[GS]ETATTR */
106 	struct  disk_zone_args bio_zone;/* Used for BIO_ZONE */
107 	struct g_consumer *bio_from;	/* GEOM linkage */
108 	struct g_provider *bio_to;	/* GEOM linkage */
109 	off_t	bio_length;		/* Like bio_bcount */
110 	off_t	bio_completed;		/* Inverse of bio_resid */
111 	u_int	bio_children;		/* Number of spawned bios */
112 	u_int	bio_inbed;		/* Children safely home by now */
113 	struct bio *bio_parent;		/* Pointer to parent */
114 	struct bintime bio_t0;		/* Time request started */
115 
116 	bio_task_t *bio_task;		/* Task_queue handler */
117 	void	*bio_task_arg;		/* Argument to above */
118 
119 	void	*bio_spare1;
120 	void	*bio_spare2;
121 
122 #ifdef DIAGNOSTIC
123 	void	*_bio_caller1;
124 	void	*_bio_caller2;
125 	uint16_t _bio_cflags;
126 #endif
127 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
128 	struct buf *bio_track_bp;	/* Parent buf for tracking */
129 #endif
130 
131 	/* XXX: these go away when bio chaining is introduced */
132 	daddr_t bio_pblkno;               /* physical block number */
133 };
134 
135 struct uio;
136 struct devstat;
137 
138 struct bio_queue_head {
139 	TAILQ_HEAD(bio_queue, bio) queue;
140 	off_t last_offset;
141 	struct	bio *insert_point;
142 	int total;
143 	int batched;
144 };
145 
146 extern int bio_transient_maxcnt;
147 
148 void biodone(struct bio *bp);
149 void biofinish(struct bio *bp, struct devstat *stat, int error);
150 int biowait(struct bio *bp, const char *wmesg);
151 
152 #if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
153 void biotrack_buf(struct bio *bp, const char *location);
154 
155 static __inline void
biotrack(struct bio * bp,const char * location)156 biotrack(struct bio *bp, const char *location)
157 {
158 
159 	if (bp->bio_track_bp != NULL)
160 		biotrack_buf(bp, location);
161 }
162 #else
163 static __inline void
biotrack(struct bio * bp __unused,const char * location __unused)164 biotrack(struct bio *bp __unused, const char *location __unused)
165 {
166 }
167 #endif
168 
169 void bioq_disksort(struct bio_queue_head *ap, struct bio *bp);
170 struct bio *bioq_first(struct bio_queue_head *head);
171 struct bio *bioq_takefirst(struct bio_queue_head *head);
172 void bioq_flush(struct bio_queue_head *head, struct devstat *stp, int error);
173 void bioq_init(struct bio_queue_head *head);
174 void bioq_insert_head(struct bio_queue_head *head, struct bio *bp);
175 void bioq_insert_tail(struct bio_queue_head *head, struct bio *bp);
176 void bioq_remove(struct bio_queue_head *head, struct bio *bp);
177 
178 int	physio(struct cdev *dev, struct uio *uio, int ioflag);
179 #define physread physio
180 #define physwrite physio
181 
182 #endif /* _KERNEL */
183 
184 #endif /* !_SYS_BIO_H_ */
185