1 /*-
2 * Copyright (c) 1990, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * William Jolitz.
7 *
8 * %sccs.include.redist.c%
9 *
10 * @(#)bootxx.c 8.1 (Berkeley) 06/11/93
11 */
12
13 #include <sys/param.h>
14 #include <sys/reboot.h>
15 #include <sys/disklabel.h>
16
17 #include <a.out.h>
18 #include <stand/saio.h>
19
20 char *bootprog = "/boot";
21 extern int opendev, bootdev, cyloffset;
22 extern struct disklabel disklabel;
23
24 /*
25 * Boot program... loads /boot out of filesystem indicated by arguements.
26 * We assume an autoboot unless we detect a misconfiguration.
27 */
28
main(dev,unit,off)29 main(dev, unit, off)
30 {
31 register struct disklabel *lp;
32 register int io, partition, howto;
33
34
35 /* are we a disk, if so look at disklabel and do things */
36 lp = &disklabel;
37 if (lp->d_magic == DISKMAGIC) {
38 /*
39 * Synthesize bootdev from dev, unit, type and partition
40 * information from the block 0 bootstrap.
41 * It's dirty work, but someone's got to do it.
42 * This will be used by the filesystem primatives, and
43 * drivers. Ultimately, opendev will be created corresponding
44 * to which drive to pass to top level bootstrap.
45 */
46 for (io = 0; io < 8; io++)
47 #ifdef notyetSCSI
48 if (lp->d_type == DTYPE_SCSI) {
49 if (lp->d_partitions[io].p_offset == off)
50 break;
51 } else
52 #endif
53 if (lp->d_partitions[io].p_offset == off*lp->d_secpercyl)
54 break;
55
56 if (io == 8) goto screwed;
57 cyloffset = off;
58 } else {
59 screwed:
60 /* probably a bad or non-existant disklabel */
61 io = 0 ;
62 howto |= RB_SINGLE|RB_ASKNAME ;
63 }
64
65 /* construct bootdev */
66 /* currently, PC has no way of booting off alternate controllers */
67 bootdev = MAKEBOOTDEV(/*i_dev*/ dev, /*i_adapt*/0, /*i_ctlr*/0,
68 unit, /*i_part*/io);
69
70 printf("loading %s\n", bootprog);
71 io = open(bootprog, 0);
72 if (io >= 0)
73 copyunix(io, howto);
74 _stop("boot failed\n");
75 }
76
77 /*ARGSUSED*/
copyunix(io,howto)78 copyunix(io, howto)
79 register io;
80 {
81 struct exec x;
82 register int i;
83 char *addr;
84
85 i = read(io, (char *)&x, sizeof x);
86 if (i != sizeof x ||
87 (x.a_magic != 0407 && x.a_magic != 0413 && x.a_magic != 0410))
88 _stop("Bad format\n");
89
90 if ((x.a_magic == 0413 || x.a_magic == 0410) &&
91 lseek(io, 0x400, 0) == -1)
92 goto shread;
93
94 if (read(io, (char *)0, x.a_text) != x.a_text)
95 goto shread;
96
97 addr = (char *)x.a_text;
98 if (x.a_magic == 0413 || x.a_magic == 0410)
99 while ((int)addr & CLOFSET)
100 *addr++ = 0;
101
102 if (read(io, addr, x.a_data) != x.a_data)
103 goto shread;
104
105 addr += x.a_data;
106 for (i = 0; i < x.a_bss; i++)
107 *addr++ = 0;
108
109 (*((int (*)()) x.a_entry))(howto, opendev, cyloffset);
110 return;
111 shread:
112 _stop("Short read\n");
113 }
114