biosdisk_user.c revision 1.4.44.2 1 /* $NetBSD: biosdisk_user.c,v 1.4.44.2 2004/09/18 14:35:57 skrll Exp $ */
2
3 /*
4 * Copyright (c) 1998
5 * Matthias Drochner. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 */
28
29 #include "sanamespace.h"
30
31 #include <stdio.h>
32 #include <unistd.h>
33 #include <fcntl.h>
34 #include <err.h>
35
36 #include "biosdisk_ll.h"
37 #include "biosdisk_user.h"
38
39 /*
40 * Replacement for i386/stand/lib/bios_disk.S.
41 * Allows to map BIOS-like device numbers to character
42 * device nodes or plain files.
43 * The actual mapping is defined in the external table
44 * "emuldisktab".
45 */
46
47 static int currentdev, currentdte;
48 static int fd = -1;
49
50 int
51 get_diskinfo(dev)
52 int dev;
53 {
54 int i, retval;
55
56 if (fd != -1) {
57 close(fd);
58 fd = -1;
59 }
60
61 i = 0;
62 for (;;) {
63 if (emuldisktab[i].biosdev == -1)
64 break;
65 if (emuldisktab[i].biosdev == dev)
66 goto ok;
67 i++;
68 }
69 warnx("unknown device %x", dev);
70 return (0); /* triggers error in set_geometry() */
71
72 ok:
73 fd = open(emuldisktab[i].name, O_RDONLY, 0);
74 if (fd < 0) {
75 warn("open %s", emuldisktab[i].name);
76 return (0);
77 }
78
79 currentdev = dev;
80 currentdte = i;
81
82 retval = ((emuldisktab[i].cyls - 1) & 0xff) << 16;
83 retval |= ((emuldisktab[i].cyls - 1) & 0x300) << 6;
84 retval |= emuldisktab[i].spt << 8;
85 retval |= emuldisktab[i].heads - 1;
86 return (retval);
87 }
88
89 int
90 biosread(dev, cyl, head, sec, nsec, buf)
91 int dev;
92 int cyl, head, sec;
93 int nsec;
94 char *buf;
95 {
96 if (dev != currentdev) {
97 warnx("biosread: unexpected device %x", dev);
98 return (-1);
99 }
100
101 if (lseek(fd, ((cyl * emuldisktab[currentdte].heads + head)
102 * emuldisktab[currentdte].spt + sec) * 512,
103 SEEK_SET) == -1) {
104 warn("lseek");
105 return (-1);
106 }
107 if (read(fd, buf, nsec * 512) != nsec * 512) {
108 warn("read");
109 return (-1);
110 }
111 return (0);
112 }
113
114 int
115 int13_extension(dev)
116 int dev;
117 {
118 return (0);
119 }
120
121 void
122 int13_getextinfo(dev, info)
123 int dev;
124 struct biosdisk_ext13info *info;
125 {
126 }
127
128 struct ext {
129 int8_t size;
130 int8_t resvd;
131 int16_t cnt;
132 int16_t off;
133 int16_t seg;
134 int64_t sec;
135 };
136
137 int
138 biosextread(dev, ext)
139 int dev;
140 struct ext *ext;
141 {
142 return (-1);
143 }
144