sys/arch/i386/stand/bootxx/boot1.c

   1 /*      $NetBSD: boot1.c,v 1.18 2009/11/18 21:02:16 dsl 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 1.18 2009/11/18 21:02:16 dsl 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         putstr("\r\nNetBSD/x86 " STR(FS) " Primary Bootstrap\r\n");
  72
  73         if (set_geometry(&d, NULL))
  74                 return "set_geometry\r\n";
  75
  76         /*
  77          * We default to the filesystem at the start of the
  78          * MBR partition
  79          */
  80         fd = ob();
  81         if (fd != -1)
  82                 goto done;
  83         /*
  84          * Maybe the filesystem is enclosed in a raid set.
  85          * add in size of raidframe header and try again.
  86          * (Maybe this should only be done if the filesystem
  87          * magic number is absent.)
  88          */
  89         bios_sector += RF_PROTECTED_SECTORS;
  90         fd = ob();
  91         if (fd != -1)
  92                 goto done;
  93         /*
  94          * Nothing at the start of the MBR partition, fallback on
  95          * partition 'a' from the disklabel in this MBR partition.
  96          */
  97         if (ptn_disklabel.d_magic != DISKMAGIC ||
  98             ptn_disklabel.d_magic2 != DISKMAGIC ||
  99             ptn_disklabel.d_partitions[0].p_fstype == FS_UNUSED)
 100                 goto done;
 101         bios_sector = ptn_disklabel.d_partitions[0].p_offset;
 102         *sector = bios_sector;
 103         if (ptn_disklabel.d_partitions[0].p_fstype == FS_RAID)
 104                 bios_sector += RF_PROTECTED_SECTORS;
 105
 106         fd = ob();
 107
 108 done:
 109         /* if we fail here, so will fstat, so keep going */
 110         if (fd == -1 || fstat(fd, &sb) == -1)
 111                 return "Can't open /boot\r\n";
 112
 113         biosdev = (uint32_t)sb.st_size;
 114 #if 0
 115         if (biosdev > SECONDARY_MAX_LOAD)
 116                 return "/boot too large\r\n";
 117 #endif
 118
 119         if (read(fd, (void *)SECONDARY_LOAD_ADDRESS, biosdev) != biosdev)
 120                 return "/boot load failed\r\n";
 121
 122         if (*(uint32_t *)(SECONDARY_LOAD_ADDRESS + 4) != X86_BOOT_MAGIC_2)
 123                 return "Invalid /boot file format\r\n";
 124
 125         /* We need to jump to the secondary bootstrap in realmode */
 126         return 0;
 127 }
 128
 129 int
 130 blkdevstrategy(void *devdata, int flag, daddr_t dblk, size_t size, void *buf, size_t *rsize)
 131 {
 132         if (flag != F_READ)
 133                 return EROFS;
 134
 135         if (size & (BIOSDISK_DEFAULT_SECSIZE - 1))
 136                 return EINVAL;
 137
 138         if (rsize)
 139                 *rsize = size;
 140
 141         if (size != 0 && readsects(&d, bios_sector + dblk,
 142                                    size / BIOSDISK_DEFAULT_SECSIZE,
 143                                    buf, 1) != 0)
 144                 return EIO;
 145
 146         return 0;
 147 }