xref: /netbsd-src/sys/arch/i386/stand/lib/biosdisk.c (revision 001c68bd94f75ce9270b69227c4199fbf34ee396)
1 /*	$NetBSD: biosdisk.c,v 1.17 2003/07/07 13:32:42 dsl Exp $	*/
2 
3 /*
4  * Copyright (c) 1996, 1998
5  *	Matthias Drochner.  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 for the NetBSD Project
18  *	by Matthias Drochner.
19  * 4. The name of the author may not be used to endorse or promote products
20  *    derived from this software without specific prior written permission.
21  *
22  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
23  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
27  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  *
33  */
34 
35 /*
36  * raw BIOS disk device for libsa.
37  * needs lowlevel parts from bios_disk.S and biosdisk_ll.c
38  * partly from netbsd:sys/arch/i386/boot/disk.c
39  * no bad144 handling!
40  *
41  * A lot of this must match sys/kern/subr_disk_mbr.c
42  */
43 
44 /*
45  * Ported to boot 386BSD by Julian Elischer (julian@tfs.com) Sept 1992
46  *
47  * Mach Operating System
48  * Copyright (c) 1992, 1991 Carnegie Mellon University
49  * All Rights Reserved.
50  *
51  * Permission to use, copy, modify and distribute this software and its
52  * documentation is hereby granted, provided that both the copyright
53  * notice and this permission notice appear in all copies of the
54  * software, derivative works or modified versions, and any portions
55  * thereof, and that both notices appear in supporting documentation.
56  *
57  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
58  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
59  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
60  *
61  * Carnegie Mellon requests users of this software to return to
62  *
63  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
64  *  School of Computer Science
65  *  Carnegie Mellon University
66  *  Pittsburgh PA 15213-3890
67  *
68  * any improvements or extensions that they make and grant Carnegie Mellon
69  * the rights to redistribute these changes.
70  */
71 
72 #include <sys/types.h>
73 #include <sys/disklabel.h>
74 
75 #include <lib/libsa/stand.h>
76 #include <lib/libsa/saerrno.h>
77 #include <machine/stdarg.h>
78 
79 #include "libi386.h"
80 #include "biosdisk_ll.h"
81 #include "biosdisk.h"
82 #ifdef _STANDALONE
83 #include "bootinfo.h"
84 #endif
85 
86 extern void memset(void *, int, size_t);
87 
88 #define BUFSIZE (1 * BIOSDISK_SECSIZE)
89 
90 struct biosdisk {
91 	struct biosdisk_ll ll;
92 	int             boff;
93 	char            buf[BUFSIZE];
94 };
95 
96 #ifdef _STANDALONE
97 static struct btinfo_bootdisk bi_disk;
98 #endif
99 
100 #define	RF_PROTECTED_SECTORS	64	/* XXX refer to <.../rf_optnames.h> */
101 
102 int boot_biossector;	/* disk sector partition might have started in */
103 
104 int
105 biosdiskstrategy(devdata, flag, dblk, size, buf, rsize)
106 	void           *devdata;
107 	int             flag;
108 	daddr_t         dblk;
109 	size_t          size;
110 	void           *buf;
111 	size_t         *rsize;
112 {
113 	struct biosdisk *d;
114 	int             blks, frag;
115 
116 	if (flag != F_READ)
117 		return (EROFS);
118 
119 	d = (struct biosdisk *) devdata;
120 
121 	dblk += d->boff;
122 
123 	blks = size / BIOSDISK_SECSIZE;
124 	if (blks && readsects(&d->ll, dblk, blks, buf, 0)) {
125 		if (rsize)
126 			*rsize = 0;
127 		return (EIO);
128 	}
129 	/* do we really need this? */
130 	frag = size % BIOSDISK_SECSIZE;
131 	if (frag) {
132 		if (readsects(&d->ll, dblk + blks, 1, d->buf, 0)) {
133 			if (rsize)
134 				*rsize = blks * BIOSDISK_SECSIZE;
135 			return (EIO);
136 		}
137 		memcpy(buf + blks * BIOSDISK_SECSIZE, d->buf, frag);
138 	}
139 	if (rsize)
140 		*rsize = size;
141 	return (0);
142 }
143 
144 static struct biosdisk *
145 alloc_biosdisk(int dev)
146 {
147 	struct biosdisk *d;
148 
149 	d = (struct biosdisk *)alloc(sizeof *d);
150 	if (!d)
151 		return NULL;
152 	memset(d, 0, sizeof *d);
153 
154 	d->ll.dev = dev;;
155 	if (set_geometry(&d->ll, NULL)) {
156 #ifdef DISK_DEBUG
157 		printf("no geometry information\n");
158 #endif
159 		free(d, sizeof *d);
160 		return NULL;
161 	}
162 	return d;
163 }
164 
165 #ifndef NO_DISKLABEL
166 static int
167 check_label(struct biosdisk *d, int sector)
168 {
169 	struct disklabel *lp;
170 
171 	/* find partition in NetBSD disklabel */
172 	if (readsects(&d->ll, sector + LABELSECTOR, 1, d->buf, 0)) {
173 #ifdef DISK_DEBUG
174 		printf("Error reading disklabel\n");
175 #endif
176 		return EIO;
177 	}
178 	lp = (struct disklabel *) (d->buf + LABELOFFSET);
179 	if (lp->d_magic != DISKMAGIC || dkcksum(lp)) {
180 #ifdef DISK_DEBUG
181 		printf("warning: no disklabel\n");
182 #endif
183 		return -1;
184 	}
185 
186 	d->boff = sector;
187 	return 0;
188 }
189 
190 static int
191 read_label(struct biosdisk *d)
192 {
193 	struct disklabel dflt_lbl;
194 	struct mbr_partition mbr[NMBRPART];
195 	struct partition *p;
196 	int sector, i;
197 	int error;
198 	int typ;
199 	int ext_base, this_ext, next_ext;
200 #ifdef COMPAT_386BSD_MBRPART
201 	int sector_386bsd = -1;
202 #endif
203 
204 	memset(&dflt_lbl, 0, sizeof dflt_lbl);
205 	dflt_lbl.d_npartitions = 8;
206 
207 	d->boff = 0;
208 
209 	if (!(d->ll.dev & 0x80)) /* floppy */
210 		/* No label on floppy */
211 		return -1;
212 
213 	/*
214 	 * find NetBSD Partition in DOS partition table
215 	 * XXX check magic???
216 	 */
217 	ext_base = 0;
218 	next_ext = 0;
219 	for (;;) {
220 		this_ext = ext_base + next_ext;
221 		next_ext = 0;
222 		if (readsects(&d->ll, this_ext, 1, d->buf, 0)) {
223 #ifdef DISK_DEBUG
224 			printf("error reading MBR sector %d\n", this_ext);
225 #endif
226 			return EIO;
227 		}
228 		memcpy(&mbr, ((mbr_sector_t *)d->buf)->mbr_parts, sizeof mbr);
229 		/* Look for NetBSD partition ID */
230 		for (i = 0; i < NMBRPART; i++) {
231 			typ = mbr[i].mbrp_typ;
232 			if (typ == 0)
233 				continue;
234 			sector = this_ext + mbr[i].mbrp_start;
235 			if (typ == MBR_PTYPE_NETBSD) {
236 				error = check_label(d, sector);
237 				if (error >= 0)
238 					return error;
239 			}
240 			if (MBR_IS_EXTENDED(typ)) {
241 				next_ext = mbr[i].mbrp_start;
242 				continue;
243 			}
244 #ifdef COMPAT_386BSD_MBRPART
245 			if (this_ext == 0 && typ == MBR_PTYPE_386BSD)
246 				sector_386bsd = sector;
247 #endif
248 			if (this_ext != 0) {
249 				if (dflt_lbl.d_npartitions >= MAXPARTITIONS)
250 					continue;
251 				p = &dflt_lbl.d_partitions[dflt_lbl.d_npartitions++];
252 			} else
253 				p = &dflt_lbl.d_partitions[i];
254 			p->p_offset = sector;
255 			p->p_size = mbr[i].mbrp_size;
256 			p->p_fstype = xlat_mbr_fstype(typ);
257 		}
258 		if (next_ext == 0)
259 			break;
260 		if (ext_base == 0) {
261 			ext_base = next_ext;
262 			next_ext = 0;
263 		}
264 	}
265 
266 	sector = 0;
267 #ifdef COMPAT_386BSD_MBRPART
268 	if (sector_386bsd != -1) {
269 		printf("old BSD partition ID!\n");
270 		sector = sector_386bsd;
271 	}
272 #endif
273 
274 	/*
275 	 * One of two things:
276 	 * 	1. no MBR
277 	 *	2. no NetBSD partition in MBR
278 	 *
279 	 * We simply default to "start of disk" in this case and
280 	 * press on.
281 	 */
282 	error = check_label(d, sector);
283 	if (error >= 0)
284 		return error;
285 
286 	/*
287 	 * Nothing at start of disk, return info from mbr partitions.
288 	 */
289 	/* XXX fill it to make checksum match kernel one */
290 	dflt_lbl.d_checksum = dkcksum(&dflt_lbl);
291 	memcpy(d->buf, &dflt_lbl, sizeof dflt_lbl);
292 	return -1;
293 }
294 #endif /* NO_DISKLABEL */
295 
296 /* Determine likely partition for possible sector number of dos
297  * partition.
298  */
299 
300 u_int
301 biosdiskfindptn(int biosdev, u_int sector)
302 {
303 #ifdef NO_DISKLABEL
304 	return 0;
305 #else
306 	struct biosdisk *d;
307 	u_int partition = 0;
308 	struct disklabel *lp;
309 
310 	/* Look for netbsd partition that is the dos boot one */
311 	d = alloc_biosdisk(biosdev);
312 	if (d == NULL)
313 		return 0;
314 
315 	if (read_label(d) == 0) {
316 		lp = (struct disklabel *)(d->buf + LABELOFFSET);
317 		for (partition = lp->d_npartitions; --partition;){
318 			if (lp->d_partitions[partition].p_fstype == FS_UNUSED)
319 				continue;
320 			if (lp->d_partitions[partition].p_offset == sector)
321 				break;
322 		}
323 	}
324 
325 	free(d, sizeof *d);
326 	return partition;
327 }
328 #endif /* NO_DISKLABEL */
329 
330 int
331 biosdiskopen(struct open_file *f, ...)
332 /* file, biosdev, partition */
333 {
334 	va_list ap;
335 	struct biosdisk *d;
336 	int partition;
337 #ifndef NO_DISKLABEL
338 	struct disklabel *lp;
339 #endif
340 	int error = 0;
341 
342 	va_start(ap, f);
343 	d = alloc_biosdisk(va_arg(ap, int));
344 	if (!d) {
345 		error = ENXIO;
346 		goto out;
347 	}
348 
349 	partition = va_arg(ap, int);
350 #ifdef _STANDALONE
351 	bi_disk.biosdev = d->ll.dev;
352 	bi_disk.partition = partition;
353 	bi_disk.labelsector = -1;
354 #endif
355 
356 #ifndef NO_DISKLABEL
357 	if (partition == RAW_PART)
358 		goto nolabel;
359 	error = read_label(d);
360 	if (error == -1) {
361 		error = 0;
362 		goto nolabel;
363 	}
364 	if (error)
365 		goto out;
366 
367 	lp = (struct disklabel *) (d->buf + LABELOFFSET);
368 	if (partition >= lp->d_npartitions ||
369 	   lp->d_partitions[partition].p_fstype == FS_UNUSED) {
370 #ifdef DISK_DEBUG
371 		printf("illegal partition\n");
372 #endif
373 		error = EPART;
374 		goto out;
375 	}
376 #ifdef _STANDALONE
377 	bi_disk.labelsector = d->boff + LABELSECTOR;
378 	bi_disk.label.type = lp->d_type;
379 	memcpy(bi_disk.label.packname, lp->d_packname, 16);
380 	bi_disk.label.checksum = lp->d_checksum;
381 #endif
382 	d->boff = lp->d_partitions[partition].p_offset;
383 	if (lp->d_partitions[partition].p_fstype == FS_RAID)
384 		d->boff += RF_PROTECTED_SECTORS;
385 nolabel:
386 #endif /* NO_DISKLABEL */
387 
388 #ifdef DISK_DEBUG
389 	printf("partition @%d\n", d->boff);
390 #endif
391 
392 #ifdef _STANDALONE
393 	BI_ADD(&bi_disk, BTINFO_BOOTDISK, sizeof(bi_disk));
394 #endif
395 
396 	f->f_devdata = d;
397 out:
398         va_end(ap);
399 	if (error)
400 		free(d, sizeof(struct biosdisk));
401 	return (error);
402 }
403 
404 #ifndef LIBSA_NO_FS_CLOSE
405 int
406 biosdiskclose(f)
407 	struct open_file *f;
408 {
409 	struct biosdisk *d = f->f_devdata;
410 
411 	if (!(d->ll.dev & 0x80))/* let the floppy drive go off */
412 		delay(3000000);	/* 2s is enough on all PCs I found */
413 
414 	free(d, sizeof(struct biosdisk));
415 	f->f_devdata = NULL;
416 	return (0);
417 }
418 #endif
419 
420 int
421 biosdiskioctl(f, cmd, arg)
422 	struct open_file *f;
423 	u_long          cmd;
424 	void           *arg;
425 {
426 	return EIO;
427 }
428