diskio.c revision 1.3 1 /* $NetBSD: diskio.c,v 1.3 2005/06/28 21:03:02 junyoung Exp $ */
2
3 /*
4 * Copyright (c) 1995 Waldi Ravens.
5 * 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 * 3. All advertising materials mentioning features or use of this software
16 * must display the following acknowledgement:
17 * This product includes software developed by Waldi Ravens.
18 * 4. The name of the author may not be used to endorse or promote products
19 * derived from this software without specific prior written permission
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include <lib/libsa/stand.h>
34 #include "atari_stand.h"
35 #include <sys/disklabel.h>
36
37 typedef int (*rdsec_f)__P((void *buffer, u_int offset, u_int count));
38 typedef struct { rdsec_f rds; u_int rst; u_int rend; } bdevd_t;
39
40 static int rootstrategy __P((void *, int, daddr_t, size_t, void *, size_t *));
41 static int rootopen __P((struct open_file *, ...));
42 static int rootclose __P((struct open_file *));
43 static int rootioctl __P((struct open_file *, u_long, void *));
44
45 static struct devsw devsw[] = {
46 { "root", rootstrategy, rootopen, rootclose, rootioctl }
47 };
48 static bdevd_t bootdev;
49
50 /*
51 * Initialise boot device info.
52 */
53 int
54 init_dskio (func, label, root)
55 void *func, *label;
56 int root;
57 {
58 struct disklabel *dl = label;
59 struct partition *pd = &dl->d_partitions[root];
60
61 if (dl->d_magic != DISKMAGIC || dl->d_magic2 != DISKMAGIC
62 || dl->d_npartitions > MAXPARTITIONS || dkcksum(dl) != 0) {
63 printf("Invalid disk label.\n");
64 return(-1);
65 }
66 if (root >= 0) {
67 if (root >= dl->d_npartitions
68 || pd->p_fstype != FS_BSDFFS || pd->p_size == 0) {
69 printf("No suitable root.\n");
70 return(-1);
71 }
72 bootdev.rds = func;
73 bootdev.rst = pd->p_offset;
74 bootdev.rend = pd->p_offset + pd->p_size - 1;
75 }
76 return(0);
77 }
78
79 /*
80 * No choice, the kernel is loaded from the
81 * same device as the bootstrap.
82 */
83 int
84 devopen (f, fname, file)
85 struct open_file *f;
86 const char *fname;
87 char **file;
88 {
89 f->f_devdata = &bootdev;
90 f->f_dev = &devsw[0];
91 *file = (char *)fname;
92 return(0);
93 }
94
95 static int
96 rootstrategy (devd, flag, dblk, size, buf, rsize)
97 void *devd;
98 int flag;
99 daddr_t dblk;
100 size_t size;
101 void *buf;
102 size_t *rsize;
103 {
104 bdevd_t *dd = devd;
105 daddr_t stb = dd->rst + dblk;
106 size_t nb = size >> 9;
107
108 if ((flag == F_READ) && !(size & 511) && (stb + nb <= dd->rend)) {
109 if (!dd->rds(buf, stb, nb)) {
110 *rsize = size;
111 return(0);
112 }
113 }
114 *rsize = 0;
115 return(EIO);
116 }
117
118 static int
119 rootopen (f)
120 struct open_file *f;
121 {
122 return(0);
123 }
124
125 static int
126 rootclose (f)
127 struct open_file *f;
128 {
129 return(EIO);
130 }
131
132 static int
133 rootioctl (f, cmd, data)
134 struct open_file *f;
135 u_long cmd;
136 void *data;
137 {
138 return(EIO);
139 }
140