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 = D_SLICENONE
34 *	d_partition = <doesn't matter>
35 *
36 * Whole MBR slice:
37 *
38 *	d_slice = MBR slice number (typically 1..4)
39 *	d_partition = D_PARTNONE
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 or D_PARTWILD)
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 or D_PARTWILD)
50 *
51 * BSD disklabel partition on the true dedicated disk:
52 *
53 *	d_slice = D_SLICENONE
54 *	d_partition = disklabel partition (typically 0..19 or D_PARTWILD)
55 *
56 * GPT partition:
57 *
58 *	d_slice = GPT partition number (typically 1..N)
59 *	d_partition = D_PARTISGPT
60 *
61 * For MBR, setting d_partition to D_PARTWILD will automatically use the first
62 * partition within the slice.
63 *
64 * For both MBR and GPT, to automatically find the 'best' slice and partition,
65 * set d_slice to D_SLICEWILD. This uses the partition type to decide which
66 * partition to use according to the following list of preferences:
67 *
68 *	Solaris2 (active)
69 *	Solaris2 (inactive)
70 *	Linux (active)
71 *	Linux (inactive)
72 *	DOS/Windows (active)
73 *	DOS/Windows (inactive)
74 *
75 * Active MBR slices (marked as bootable) are preferred over inactive. GPT
76 * doesn't have the concept of active/inactive partitions. In both MBR and GPT,
77 * if there are multiple slices/partitions of a given type, the first one
78 * is chosen.
79 *
80 * The low-level disk device will typically call disk_open() from its open
81 * method to interpret the disk partition tables according to the rules above.
82 * This will initialize d_offset to the block offset of the start of the
83 * selected partition - this offset should be added to the offset passed to
84 * the device's strategy method.
85 */
86
87#ifndef	_DISK_H
88#define	_DISK_H
89
90#define	D_SLICENONE	-1
91#define	D_SLICEWILD	0
92#define	D_PARTNONE	-1
93#define	D_PARTWILD	-2
94#define	D_PARTISGPT	255
95
96struct disk_devdesc {
97	struct devdesc	dd;		/* Must be first. */
98	int		d_slice;
99	int		d_partition;
100	uint64_t	d_offset;
101};
102
103enum disk_ioctl {
104	IOCTL_GET_BLOCKS,
105	IOCTL_GET_BLOCK_SIZE
106};
107
108/*
109 * Parse disk metadata and initialise dev->d_offset.
110 */
111extern int disk_open(struct disk_devdesc *, uint64_t, u_int);
112extern int disk_close(struct disk_devdesc *);
113extern int disk_ioctl(struct disk_devdesc *, u_long, void *);
114extern int disk_read(struct disk_devdesc *, void *, uint64_t, u_int);
115extern int disk_write(struct disk_devdesc *, void *, uint64_t, u_int);
116
117/*
118 * Print information about slices on a disk.
119 */
120extern int disk_print(struct disk_devdesc *, char *, int);
121extern char* disk_fmtdev(struct disk_devdesc *);
122extern int disk_parsedev(struct disk_devdesc *, const char *, const char **);
123
124#endif	/* _DISK_H */
125