xref: /titanic_52/usr/src/boot/sys/boot/common/disk.h (revision 1ec96012c7fa9330cf4f439d7155d9c218d9512f)
1 /*-
2  * Copyright (c) 2011 Google, Inc.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 /*
28  * Device descriptor for partitioned disks. To use, set the
29  * d_slice and d_partition variables as follows:
30  *
31  * Whole disk access:
32  *
33  * 	d_slice = -1
34  * 	d_partition = -1
35  *
36  * Whole MBR slice:
37  *
38  * 	d_slice = MBR slice number (typically 1..4)
39  * 	d_partition = -1
40  *
41  * VTOC disklabel partition within an MBR slice:
42  *
43  * 	d_slice = MBR slice number (typically 1..4)
44  * 	d_partition = disklabel partition (typically 0..19)
45  *
46  * BSD disklabel partition within an MBR slice:
47  *
48  * 	d_slice = MBR slice number (typically 1..4)
49  * 	d_partition = disklabel partition (typically 0..19)
50  *
51  * BSD disklabel partition on the true dedicated disk:
52  *
53  * 	d_slice = -1
54  * 	d_partition = disklabel partition (typically 0..19)
55  *
56  * GPT partition:
57  *
58  * 	d_slice = GPT partition number (typically 1..N)
59  * 	d_partition = 255
60  *
61  * For both MBR and GPT, to automatically find the 'best' slice or partition,
62  * set d_slice to zero. This uses the partition type to decide which partition
63  * to use according to the following list of preferences:
64  *
65  * 	Solaris2 (active)
66  * 	Solaris2 (inactive)
67  * 	Linux (active)
68  * 	Linux (inactive)
69  * 	DOS/Windows (active)
70  * 	DOS/Windows (inactive)
71  *
72  * Active MBR slices (marked as bootable) are preferred over inactive. GPT
73  * doesn't have the concept of active/inactive partitions. In both MBR and GPT,
74  * if there are multiple slices/partitions of a given type, the first one
75  * is chosen.
76  *
77  * The low-level disk device will typically call disk_open() from its open
78  * method to interpret the disk partition tables according to the rules above.
79  * This will initialize d_offset to the block offset of the start of the
80  * selected partition - this offset should be added to the offset passed to
81  * the device's strategy method.
82  */
83 
84 #ifndef	_DISK_H
85 #define	_DISK_H
86 
87 struct disk_devdesc
88 {
89 	struct devsw	*d_dev;
90 	int		d_type;
91 	int		d_unit;
92 	void		*d_opendata;
93 	int		d_slice;
94 	int		d_partition;
95 	uint64_t	d_offset;
96 };
97 
98 enum disk_ioctl {
99 	IOCTL_GET_BLOCKS,
100 	IOCTL_GET_BLOCK_SIZE
101 };
102 
103 /*
104  * Parse disk metadata and initialise dev->d_offset.
105  */
106 extern int disk_open(struct disk_devdesc *, uint64_t, u_int);
107 extern int disk_close(struct disk_devdesc *);
108 extern int disk_ioctl(struct disk_devdesc *, u_long, void *);
109 extern int disk_read(struct disk_devdesc *, void *, uint64_t, u_int);
110 extern int disk_write(struct disk_devdesc *, void *, uint64_t, u_int);
111 
112 /*
113  * Print information about slices on a disk.
114  */
115 extern int disk_print(struct disk_devdesc *, char *, int);
116 extern char* disk_fmtdev(struct disk_devdesc *);
117 extern int disk_parsedev(struct disk_devdesc *, const char *, const char **);
118 
119 #endif	/* _DISK_H */
120