1/*	$NetBSD: diskio.c,v 1.9 2021/05/17 19:31:38 mrg 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#include <lib/libkern/libkern.h>
38
39typedef int (*rdsec_f)(void *buffer, u_int offset, u_int count);
40typedef	struct { rdsec_f rds; u_int rst; u_int rend; } bdevd_t;
41
42static int rootstrategy(void *, int, daddr_t, size_t, void *, size_t *);
43static int rootopen(struct open_file *, ...);
44static int rootclose(struct open_file *);
45static int rootioctl(struct open_file *, u_long, void *);
46
47struct devsw devsw[] = {
48	{ "root", rootstrategy, rootopen, rootclose, rootioctl }
49};
50static bdevd_t	bootdev;
51
52/*
53 * Initialise boot device info.
54 */
55int
56init_dskio (void *func, void *label, 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 */
83int
84devopen (struct open_file *f, const char *fname, char **file)
85{
86	f->f_devdata = &bootdev;
87	f->f_dev = &devsw[0];
88	*file = (char *)fname;
89	return(0);
90}
91
92static int
93rootstrategy (void *devd, int flag, daddr_t dblk, size_t size, void *buf, size_t *rsize)
94{
95	bdevd_t	*dd = devd;
96	daddr_t stb = dd->rst + dblk;
97	size_t	nb  = size >> 9;
98
99	if ((flag == F_READ) && !(size & 511) && (stb + nb <= dd->rend)) {
100		if (!dd->rds(buf, stb, nb)) {
101			*rsize = size;
102			return(0);
103		}
104	}
105	*rsize = 0;
106	return(EIO);
107}
108
109static int
110rootopen (struct open_file *f, ...)
111{
112	return(0);
113}
114
115static int
116rootclose (struct open_file *f)
117{
118	return(EIO);
119}
120
121static int
122rootioctl (struct open_file *f, u_long cmd, void *data)
123{
124	return(EIO);
125}
126