disksubr.c revision 1.28 
1/*	$NetBSD: disksubr.c,v 1.28 2000/03/03 17:51:26 mhitch Exp $	*/
2
3/*
4 * Copyright (c) 1982, 1986, 1988 Regents of the University of California.
5 * 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 by the University of
18 *	California, Berkeley and its contributors.
19 * 4. Neither the name of the University nor the names of its contributors
20 *    may be used to endorse or promote products derived from this software
21 *    without specific prior written permission.
22 *
23 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 *
35 *	@(#)ufs_disksubr.c	7.16 (Berkeley) 5/4/91
36 */
37
38#include "opt_compat_ultrix.h"
39
40#include <sys/param.h>
41#include <sys/systm.h>
42#include <sys/buf.h>
43#include <sys/disk.h>
44#include <sys/disklabel.h>
45
46#ifdef COMPAT_ULTRIX
47#include <machine/dec_boot.h>
48#include <ufs/ufs/dinode.h>		/* XXX for fs.h */
49#include <ufs/ffs/fs.h>			/* XXX for BBSIZE & SBSIZE */
50
51char	*compat_label __P((dev_t dev, void (*strat) __P((struct buf *bp)),
52	    struct disklabel *lp, struct cpu_disklabel *osdep));	/* XXX */
53
54#endif
55
56/*
57 * Attempt to read a disk label from a device
58 * using the indicated stategy routine.
59 * The label must be partly set up before this:
60 * secpercyl and anything required in the strategy routine
61 * (e.g., sector size) must be filled in before calling us.
62 * Returns null on success and an error string on failure.
63 */
64char *
65readdisklabel(dev, strat, lp, osdep)
66	dev_t dev;
67	void (*strat) __P((struct buf *bp));
68	struct disklabel *lp;
69	struct cpu_disklabel *osdep;
70{
71	struct buf *bp;
72	struct disklabel *dlp;
73	char *msg = NULL;
74
75	if (lp->d_secperunit == 0)
76		lp->d_secperunit = 0x1fffffff;
77	lp->d_npartitions = 1;
78	if (lp->d_partitions[0].p_size == 0)
79		lp->d_partitions[0].p_size = 0x1fffffff;
80	lp->d_partitions[0].p_offset = 0;
81
82	bp = geteblk((int)lp->d_secsize);
83	bp->b_dev = dev;
84	bp->b_blkno = LABELSECTOR;
85	bp->b_bcount = lp->d_secsize;
86	bp->b_flags = B_BUSY | B_READ;
87	bp->b_cylinder = LABELSECTOR / lp->d_secpercyl;
88	(*strat)(bp);
89	if (biowait(bp)) {
90		msg = "I/O error";
91	} else for (dlp = (struct disklabel *)bp->b_un.b_addr;
92	    dlp <= (struct disklabel *)(bp->b_un.b_addr+DEV_BSIZE-sizeof(*dlp));
93	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
94		if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC) {
95			if (msg == NULL)
96				msg = "no disk label";
97		} else if (dlp->d_npartitions > MAXPARTITIONS ||
98			   dkcksum(dlp) != 0)
99			msg = "disk label corrupted";
100		else {
101			*lp = *dlp;
102			msg = NULL;
103			break;
104		}
105	}
106	bp->b_flags = B_INVAL | B_AGE;
107	brelse(bp);
108#ifdef COMPAT_ULTRIX
109	/*
110	 * If no NetBSD label was found, check for an Ultrix label and
111	 * construct tne incore label from the Ultrix partition information.
112	 */
113	if (msg != NULL) {
114		msg = compat_label(dev, strat, lp, osdep);
115		if (msg == NULL) {
116			printf("WARNING: using Ultrix partition information\n");
117			/* set geometry? */
118		}
119	}
120#endif
121/* XXX If no NetBSD label or Ultrix label found, generate default label here */
122	return (msg);
123}
124
125#ifdef COMPAT_ULTRIX
126/*
127 * Given a buffer bp, try and interpret it as an Ultrix disk label,
128 * putting the partition info into a native NetBSD label
129 */
130char *
131compat_label(dev, strat, lp, osdep)
132	dev_t dev;
133	void (*strat) __P((struct buf *bp));
134	struct disklabel *lp;
135	struct cpu_disklabel *osdep;
136{
137	dec_disklabel *dlp;
138	struct buf *bp = NULL;
139	char *msg = NULL;
140
141	bp = geteblk((int)lp->d_secsize);
142	bp->b_dev = dev;
143	bp->b_blkno = DEC_LABEL_SECTOR;
144	bp->b_bcount = lp->d_secsize;
145	bp->b_flags = B_BUSY | B_READ;
146	bp->b_cylinder = DEC_LABEL_SECTOR / lp->d_secpercyl;
147	(*strat)(bp);
148
149	if (biowait(bp)) {
150                msg = "I/O error";
151		goto done;
152	}
153
154	for (dlp = (dec_disklabel *)bp->b_un.b_addr;
155	     dlp <= (dec_disklabel *)(bp->b_un.b_addr+DEV_BSIZE-sizeof(*dlp));
156	     dlp = (dec_disklabel *)((char *)dlp + sizeof(long))) {
157
158		int part;
159
160		if (dlp->magic != DEC_LABEL_MAGIC) {
161			printf("label: %x\n",dlp->magic);
162			msg = ((msg != NULL) ? msg: "no disk label");
163			goto done;
164		}
165
166#ifdef DIAGNOSTIC
167/*XXX*/		printf("Interpreting Ultrix label\n");
168#endif
169
170		lp->d_magic = DEC_LABEL_MAGIC;
171		lp->d_npartitions = 0;
172		strncpy(lp->d_packname, "Ultrix label", 16);
173		lp->d_rpm = 3600;
174		lp->d_interleave = 1;
175		lp->d_flags = 0;
176		lp->d_bbsize = BBSIZE;
177		lp->d_sbsize = SBSIZE;
178		for (part = 0;
179		     part <((MAXPARTITIONS<DEC_NUM_DISK_PARTS) ?
180			    MAXPARTITIONS : DEC_NUM_DISK_PARTS);
181		     part++) {
182			lp->d_partitions[part].p_size = dlp->map[part].num_blocks;
183			lp->d_partitions[part].p_offset = dlp->map[part].start_block;
184			lp->d_partitions[part].p_fsize = 1024;
185			lp->d_partitions[part].p_fstype =
186			  (part==1) ? FS_SWAP : FS_BSDFFS;
187			lp->d_npartitions += 1;
188
189#ifdef DIAGNOSTIC
190			printf(" Ultrix label rz%d%c: start %d len %d\n",
191			       DISKUNIT(dev), "abcdefgh"[part],
192			       lp->d_partitions[part].p_offset,
193			       lp->d_partitions[part].p_size);
194#endif
195		}
196		break;
197	}
198
199done:
200	bp->b_flags = B_INVAL | B_AGE;
201	brelse(bp);
202	return (msg);
203}
204#endif /* COMPAT_ULTRIX */
205
206
207/*
208 * Check new disk label for sensibility
209 * before setting it.
210 */
211int
212setdisklabel(olp, nlp, openmask, osdep)
213	struct disklabel *olp, *nlp;
214	u_long openmask;
215	struct cpu_disklabel *osdep;
216{
217	int i;
218	struct partition *opp, *npp;
219
220	if (nlp->d_magic != DISKMAGIC || nlp->d_magic2 != DISKMAGIC ||
221	    dkcksum(nlp) != 0)
222		return (EINVAL);
223	while ((i = ffs((long)openmask)) != 0) {
224		i--;
225		openmask &= ~(1 << i);
226		if (nlp->d_npartitions <= i)
227			return (EBUSY);
228		opp = &olp->d_partitions[i];
229		npp = &nlp->d_partitions[i];
230		if (npp->p_offset != opp->p_offset || npp->p_size < opp->p_size)
231			return (EBUSY);
232		/*
233		 * Copy internally-set partition information
234		 * if new label doesn't include it.		XXX
235		 */
236		if (npp->p_fstype == FS_UNUSED && opp->p_fstype != FS_UNUSED) {
237			npp->p_fstype = opp->p_fstype;
238			npp->p_fsize = opp->p_fsize;
239			npp->p_frag = opp->p_frag;
240			npp->p_cpg = opp->p_cpg;
241		}
242	}
243 	nlp->d_checksum = 0;
244 	nlp->d_checksum = dkcksum(nlp);
245	*olp = *nlp;
246	return (0);
247}
248
249/* encoding of disk minor numbers, should be elsewhere... */
250#define dkunit(dev)		(minor(dev) >> 3)
251#define dkpart(dev)		(minor(dev) & 07)
252#define dkminor(unit, part)	(((unit) << 3) | (part))
253
254/*
255 * Write disk label back to device after modification.
256 */
257int
258writedisklabel(dev, strat, lp, osdep)
259	dev_t dev;
260	void (*strat) __P((struct buf *bp));
261	struct disklabel *lp;
262	struct cpu_disklabel *osdep;
263{
264	struct buf *bp;
265	struct disklabel *dlp;
266	int labelpart;
267	int error = 0;
268
269	labelpart = dkpart(dev);
270	if (lp->d_partitions[labelpart].p_offset != 0) {
271		if (lp->d_partitions[0].p_offset != 0)
272			return (EXDEV);			/* not quite right */
273		labelpart = 0;
274	}
275	bp = geteblk((int)lp->d_secsize);
276	bp->b_dev = makedev(major(dev), dkminor(dkunit(dev), labelpart));
277	bp->b_blkno = LABELSECTOR;
278	bp->b_bcount = lp->d_secsize;
279	bp->b_flags = B_READ;
280	(*strat)(bp);
281	if ((error = biowait(bp)) != 0)
282		goto done;
283	for (dlp = (struct disklabel *)bp->b_un.b_addr;
284	    dlp <= (struct disklabel *)
285	      (bp->b_un.b_addr + lp->d_secsize - sizeof(*dlp));
286	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
287		if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC &&
288		    dkcksum(dlp) == 0) {
289			*dlp = *lp;
290			bp->b_flags = B_WRITE;
291			(*strat)(bp);
292			error = biowait(bp);
293			goto done;
294		}
295	}
296	error = ESRCH;
297done:
298	brelse(bp);
299	return (error);
300}
301
302/*
303 * UNTESTED !!
304 *
305 * Determine the size of the transfer, and make sure it is
306 * within the boundaries of the partition. Adjust transfer
307 * if needed, and signal errors or early completion.
308 */
309int
310bounds_check_with_label(bp, lp, wlabel)
311	struct buf *bp;
312	struct disklabel *lp;
313	int wlabel;
314{
315
316	struct partition *p = lp->d_partitions + dkpart(bp->b_dev);
317	int labelsect = lp->d_partitions[RAW_PART].p_offset;
318	int maxsz = p->p_size;
319	int sz = (bp->b_bcount + DEV_BSIZE - 1) >> DEV_BSHIFT;
320
321	/* overwriting disk label ? */
322	/* XXX should also protect bootstrap in first 8K */
323	if (bp->b_blkno + p->p_offset <= LABELSECTOR + labelsect &&
324	    (bp->b_flags & B_READ) == 0 && wlabel == 0) {
325		bp->b_error = EROFS;
326		goto bad;
327	}
328
329	/* beyond partition? */
330	if (bp->b_blkno < 0 || bp->b_blkno + sz > maxsz) {
331		/* if exactly at end of disk, return an EOF */
332		if (bp->b_blkno == maxsz) {
333			bp->b_resid = bp->b_bcount;
334			return(0);
335		}
336		/* or truncate if part of it fits */
337		sz = maxsz - bp->b_blkno;
338		if (sz <= 0) {
339			bp->b_error = EINVAL;
340			goto bad;
341		}
342		bp->b_bcount = sz << DEV_BSHIFT;
343	}
344
345	/* calculate cylinder for disksort to order transfers with */
346	bp->b_resid = (bp->b_blkno + p->p_offset) / lp->d_secpercyl;
347	return(1);
348bad:
349	bp->b_flags |= B_ERROR;
350	return(-1);
351}
352