2 * Mach Operating System
3 * Copyright (c) 1992, 1991 Carnegie Mellon University
6 * Permission to use, copy, modify and distribute this software and its
7 * documentation is hereby granted, provided that both the copyright
8 * notice and this permission notice appear in all copies of the
9 * software, derivative works or modified versions, and any portions
10 * thereof, and that both notices appear in supporting documentation.
12 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
13 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
14 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
16 * Carnegie Mellon requests users of this software to return to
18 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
19 * School of Computer Science
20 * Carnegie Mellon University
21 * Pittsburgh PA 15213-3890
23 * any improvements or extensions that they make and grant Carnegie Mellon
24 * the rights to redistribute these changes.
26 * from: Mach, Revision 2.2 92/04/04 11:35:49 rpd
27 * $FreeBSD: src/sys/i386/boot/biosboot/disk.c,v 1.28 1999/12/08 09:32:48 phk Exp $
28 * $DragonFly: src/sys/platform/pc32/boot/biosboot/Attic/disk.c,v 1.2 2003/06/17 04:28:34 dillon Exp $
33 * If there is no 386BSD partition, initialize the label sector with
34 * LABELSECTOR instead of with garbage.
37 * Fixed reading of bad sector table. It is at the end of the 'c'
38 * partition, which is not always at the end of the disk.
42 #include <sys/disklabel.h>
43 #include <sys/diskslice.h>
45 #define BIOS_DEV_FLOPPY 0x0
46 #define BIOS_DEV_WIN 0x80
49 #define SPT(di) ((di)&0xff)
50 #define HEADS(di) ((((di)>>8)&0xff)+1)
58 int dosdev, unit, slice, part, maj, boff;
60 /*#define EMBEDDED_DISKLABEL 1*/
62 /* Read ahead buffer large enough for one track on a 1440K floppy. For
63 * reading from floppies, the bootstrap has to be loaded on a 64K boundary
64 * to ensure that this buffer doesn't cross a 64K DMA boundary.
67 static char ra_buf[RA_SECTORS * BPS];
72 static char *Bread(int dosdev, int sector);
77 struct dos_partition *dptr;
80 int i, sector = 0, di, dosdev_copy;
83 di = get_diskinfo(dosdev_copy);
86 /* Hack for 2.88MB floppy drives. */
87 if (!(dosdev_copy & 0x80) && spt == 36)
90 spc = spt * HEADS(di);
94 #ifdef EMBEDDED_DISKLABEL
96 #else EMBEDDED_DISKLABEL
97 p = Bread(dosdev_copy, 0);
98 dptr = (struct dos_partition *)(p+DOSPARTOFF);
99 slice = WHOLE_DISK_SLICE;
100 for (i = 0; i < NDOSPART; i++, dptr++)
101 if (dptr->dp_typ == DOSPTYP_386BSD) {
102 slice = BASE_SLICE + i;
103 sector = dptr->dp_start;
106 p = Bread(dosdev_copy, sector + LABELSECTOR);
107 dl=((struct disklabel *)p);
108 disklabel = *dl; /* structure copy (maybe useful later)*/
109 #endif EMBEDDED_DISKLABEL
110 if (dl->d_magic != DISKMAGIC) {
111 printf("bad disklabel\n");
114 if( (maj == 4) || (maj == 0) || (maj == 1))
116 if (dl->d_type == DTYPE_SCSI)
118 maj = 4; /* use scsi as boot dev */
122 maj = 0; /* must be ESDI/IDE */
125 /* This little trick is for OnTrack DiskManager disks */
126 boff = dl->d_partitions[part].p_offset -
127 dl->d_partitions[2].p_offset + sector;
129 bsize = dl->d_partitions[part].p_size;
131 printf("empty partition\n");
142 * Be aware that cnt is rounded up to N*BPS
145 devread(char *iodest, int sector, int cnt)
151 for (offset = 0; offset < cnt; offset += BPS)
153 dosdev_copy = dosdev;
154 p = Bread(dosdev_copy, sector++);
155 bcopy(p, iodest+offset, BPS);
161 Bread(int dosdev, int sector)
163 if (dosdev != ra_dev || sector < ra_first || sector >= ra_end)
165 int cyl, head, sec, nsec;
169 printf("Error: C:%d > 1023 (BIOS limit)\n", cyl);
170 for(;;); /* loop forever */
172 head = (sector % spc) / spt;
175 if (nsec > RA_SECTORS)
178 if (biosread(dosdev, cyl, head, sec, nsec, ra_buf) != 0)
182 while (biosread(dosdev, cyl, head, sec, nsec, ra_buf) != 0) {
183 printf("Error: D:0x%x C:%d H:%d S:%d\n",
184 dosdev, cyl, head, sec);
190 ra_end = sector + nsec;
192 return (ra_buf + (sector - ra_first) * BPS);