xref: /netbsd-src/sys/arch/i386/stand/bootxx/boot1.c (revision 274254cdae52594c1aa480a736aef78313d15c9c)
1 /*	$NetBSD: boot1.c,v 1.17 2008/04/30 16:18:26 ad Exp $	*/
2 
3 /*-
4  * Copyright (c) 2003 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by David Laight.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __RCSID("$NetBSD: boot1.c,v 1.17 2008/04/30 16:18:26 ad Exp $");
34 
35 #include <lib/libsa/stand.h>
36 #include <lib/libkern/libkern.h>
37 #include <biosdisk_ll.h>
38 
39 #include <sys/param.h>
40 #include <sys/bootblock.h>
41 #include <sys/disklabel.h>
42 #include <dev/raidframe/raidframevar.h>	/* For RF_PROTECTED_SECTORS */
43 
44 #define XSTR(x) #x
45 #define STR(x) XSTR(x)
46 
47 static uint32_t bios_sector;
48 
49 static struct biosdisk_ll d;
50 
51 const char *boot1(uint32_t, uint32_t *);
52 extern void putstr(const char *);
53 
54 extern struct disklabel ptn_disklabel;
55 
56 static int
57 ob(void)
58 {
59 	return open("boot", 0);
60 }
61 
62 const char *
63 boot1(uint32_t biosdev, uint32_t *sector)
64 {
65         struct stat sb;
66 	int fd;
67 
68 	bios_sector = *sector;
69 	d.dev = biosdev;
70 
71 #ifdef SHOW_BANNER
72         putstr("\r\nNetBSD/x86 " STR(FS) " Primary Bootstrap\r\n");
73 #endif
74 
75 	if (set_geometry(&d, NULL))
76 		return "set_geometry\r\n";
77 
78 	/*
79 	 * We default to the filesystem at the start of the
80 	 * MBR partition
81 	 */
82 	fd = ob();
83 	if (fd != -1)
84 		goto done;
85 	/*
86 	 * Maybe the filesystem is enclosed in a raid set.
87 	 * add in size of raidframe header and try again.
88 	 * (Maybe this should only be done if the filesystem
89 	 * magic number is absent.)
90 	 */
91 	bios_sector += RF_PROTECTED_SECTORS;
92 	fd = ob();
93 	if (fd != -1)
94 		goto done;
95 	/*
96 	 * Nothing at the start of the MBR partition, fallback on
97 	 * partition 'a' from the disklabel in this MBR partition.
98 	 */
99 	if (ptn_disklabel.d_magic != DISKMAGIC ||
100 	    ptn_disklabel.d_magic2 != DISKMAGIC ||
101 	    ptn_disklabel.d_partitions[0].p_fstype == FS_UNUSED)
102 		goto done;
103 	bios_sector = ptn_disklabel.d_partitions[0].p_offset;
104 	*sector = bios_sector;
105 	if (ptn_disklabel.d_partitions[0].p_fstype == FS_RAID)
106 		bios_sector += RF_PROTECTED_SECTORS;
107 
108 	fd = ob();
109 
110 done:
111 	/* if we fail here, so will fstat, so keep going */
112 	if (fstat(fd, &sb) == -1) {
113 		return "Can't open /boot\r\n";
114 	}
115 
116 	biosdev = (uint32_t)sb.st_size;
117 #if 0
118 	if (biosdev > SECONDARY_MAX_LOAD)
119 		return "/boot too large\r\n";
120 #endif
121 
122 	if (read(fd, (void *)SECONDARY_LOAD_ADDRESS, biosdev) != biosdev)
123 		return "/boot load failed\r\n";
124 
125 	if (*(uint32_t *)(SECONDARY_LOAD_ADDRESS + 4) != X86_BOOT_MAGIC_2)
126 		return "Invalid /boot file format\r\n";
127 
128 	/* We need to jump to the secondary bootstrap in realmode */
129 	return 0;
130 }
131 
132 int
133 blkdevstrategy(void *devdata, int flag, daddr_t dblk, size_t size, void *buf, size_t *rsize)
134 {
135 	if (flag != F_READ)
136 		return EROFS;
137 
138 	if (size & (BIOSDISK_DEFAULT_SECSIZE - 1))
139 		return EINVAL;
140 
141 	if (rsize)
142 		*rsize = size;
143 
144 	if (size != 0 && readsects(&d, bios_sector + dblk,
145 				   size / BIOSDISK_DEFAULT_SECSIZE,
146 				   buf, 1) != 0)
147 		return EIO;
148 
149 	return 0;
150 }
151