disksubr.c revision 1.53
1/*	$NetBSD: disksubr.c,v 1.53 2009/07/20 17:05:13 tsutsui 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. Neither the name of the University nor the names of its contributors
16 *    may be used to endorse or promote products derived from this software
17 *    without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 *
31 *	@(#)ufs_disksubr.c	7.16 (Berkeley) 5/4/91
32 */
33
34#include <sys/cdefs.h>
35__KERNEL_RCSID(0, "$NetBSD: disksubr.c,v 1.53 2009/07/20 17:05:13 tsutsui Exp $");
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/buf.h>
40#include <sys/disk.h>
41#include <sys/disklabel.h>
42
43#include <dev/dec/dec_boot.h>
44#include <ufs/ufs/dinode.h>		/* XXX for fs.h */
45#include <ufs/ffs/fs.h>			/* XXX for BBSIZE & SBSIZE */
46
47const char *compat_label(dev_t dev, void (*strat)(struct buf *bp),
48	struct disklabel *lp, struct cpu_disklabel *osdep);	/* XXX */
49
50/*
51 * Attempt to read a disk label from a device
52 * using the indicated strategy routine.
53 * The label must be partly set up before this:
54 * secpercyl and anything required in the strategy routine
55 * (e.g., sector size) must be filled in before calling us.
56 * Returns null on success and an error string on failure.
57 */
58const char *
59readdisklabel(dev_t dev, void (*strat)(struct buf *bp), struct disklabel *lp,
60    struct cpu_disklabel *osdep)
61{
62	struct buf *bp;
63	struct disklabel *dlp;
64	const char *msg = NULL;
65
66	if (lp->d_secperunit == 0)
67		lp->d_secperunit = 0x1fffffff;
68	lp->d_npartitions = 1;
69	if (lp->d_partitions[0].p_size == 0)
70		lp->d_partitions[0].p_size = 0x1fffffff;
71	lp->d_partitions[0].p_offset = 0;
72
73	bp = geteblk((int)lp->d_secsize);
74	bp->b_dev = dev;
75	bp->b_blkno = LABELSECTOR;
76	bp->b_bcount = lp->d_secsize;
77	bp->b_flags |= B_READ;
78	bp->b_cylinder = LABELSECTOR / lp->d_secpercyl;
79	(*strat)(bp);
80	if (biowait(bp)) {
81		msg = "I/O error";
82	} else for (dlp = (struct disklabel *)bp->b_data;
83	    dlp <= (struct disklabel *)
84	    ((char *)bp->b_data + DEV_BSIZE - sizeof(*dlp));
85	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
86		if (dlp->d_magic != DISKMAGIC || dlp->d_magic2 != DISKMAGIC) {
87			if (msg == NULL)
88				msg = "no disk label";
89		} else if (dlp->d_npartitions > MAXPARTITIONS ||
90			   dkcksum(dlp) != 0)
91			msg = "disk label corrupted";
92		else {
93			*lp = *dlp;
94			msg = NULL;
95			break;
96		}
97	}
98	brelse(bp, 0);
99	/*
100	 * If no NetBSD label was found, check for an Ultrix label and
101	 * construct tne incore label from the Ultrix partition information.
102	 */
103	if (msg != NULL) {
104		msg = compat_label(dev, strat, lp, osdep);
105		if (msg == NULL) {
106			printf("WARNING: using Ultrix partition information\n");
107			/* set geometry? */
108		}
109	}
110/* XXX If no NetBSD label or Ultrix label found, generate default label here */
111	return msg;
112}
113
114/*
115 * Given a buffer bp, try and interpret it as an Ultrix disk label,
116 * putting the partition info into a native NetBSD label
117 */
118const char *
119compat_label(dev_t dev, void (*strat)(struct buf *bp), struct disklabel *lp,
120    struct cpu_disklabel *osdep)
121{
122	dec_disklabel *dlp;
123	struct buf *bp = NULL;
124	const char *msg = NULL;
125
126	bp = geteblk((int)lp->d_secsize);
127	bp->b_dev = dev;
128	bp->b_blkno = DEC_LABEL_SECTOR;
129	bp->b_bcount = lp->d_secsize;
130	bp->b_flags |= B_READ;
131	bp->b_cylinder = DEC_LABEL_SECTOR / lp->d_secpercyl;
132	(*strat)(bp);
133
134	if (biowait(bp)) {
135                msg = "I/O error";
136		goto done;
137	}
138
139	for (dlp = (dec_disklabel *)bp->b_data;
140	     dlp <= (dec_disklabel *)
141	     ((char *)bp->b_data + DEV_BSIZE - sizeof(*dlp));
142	     dlp = (dec_disklabel *)((char *)dlp + sizeof(long))) {
143
144		int part;
145
146		if (dlp->magic != DEC_LABEL_MAGIC) {
147			printf("label: %x\n",dlp->magic);
148			msg = ((msg != NULL) ? msg: "no disk label");
149			goto done;
150		}
151
152#ifdef DIAGNOSTIC
153/*XXX*/		printf("Interpreting Ultrix label\n");
154#endif
155
156		lp->d_magic = DEC_LABEL_MAGIC;
157		lp->d_npartitions = 0;
158		strncpy(lp->d_packname, "Ultrix label", 16);
159		lp->d_rpm = 3600;
160		lp->d_interleave = 1;
161		lp->d_flags = 0;
162		lp->d_bbsize = BBSIZE;
163		lp->d_sbsize = SBLOCKSIZE;
164		for (part = 0;
165		     part <((MAXPARTITIONS<DEC_NUM_DISK_PARTS) ?
166			    MAXPARTITIONS : DEC_NUM_DISK_PARTS);
167		     part++) {
168			lp->d_partitions[part].p_size =
169			    dlp->map[part].num_blocks;
170			lp->d_partitions[part].p_offset =
171			    dlp->map[part].start_block;
172			lp->d_partitions[part].p_fsize = 1024;
173			lp->d_partitions[part].p_fstype =
174			  (part==1) ? FS_SWAP : FS_BSDFFS;
175			lp->d_npartitions += 1;
176
177#ifdef DIAGNOSTIC
178			printf(" Ultrix label rz%d%c: start %d len %d\n",
179			       DISKUNIT(dev), "abcdefgh"[part],
180			       lp->d_partitions[part].p_offset,
181			       lp->d_partitions[part].p_size);
182#endif
183		}
184		break;
185	}
186
187done:
188	brelse(bp, 0);
189	return msg;
190}
191
192/*
193 * Check new disk label for sensibility
194 * before setting it.
195 */
196int
197setdisklabel(struct disklabel *olp, struct disklabel *nlp, u_long openmask,
198    struct cpu_disklabel *osdep)
199{
200	int i;
201	struct partition *opp, *npp;
202
203	if (nlp->d_magic != DISKMAGIC || nlp->d_magic2 != DISKMAGIC ||
204	    dkcksum(nlp) != 0)
205		return EINVAL;
206	while ((i = ffs(openmask)) != 0) {
207		i--;
208		openmask &= ~(1 << i);
209		if (nlp->d_npartitions <= i)
210			return EBUSY;
211		opp = &olp->d_partitions[i];
212		npp = &nlp->d_partitions[i];
213		if (npp->p_offset != opp->p_offset || npp->p_size < opp->p_size)
214			return EBUSY;
215		/*
216		 * Copy internally-set partition information
217		 * if new label doesn't include it.		XXX
218		 */
219		if (npp->p_fstype == FS_UNUSED && opp->p_fstype != FS_UNUSED) {
220			npp->p_fstype = opp->p_fstype;
221			npp->p_fsize = opp->p_fsize;
222			npp->p_frag = opp->p_frag;
223			npp->p_cpg = opp->p_cpg;
224		}
225	}
226 	nlp->d_checksum = 0;
227 	nlp->d_checksum = dkcksum(nlp);
228	*olp = *nlp;
229	return 0;
230}
231
232/*
233 * Write disk label back to device after modification.
234 */
235int
236writedisklabel(dev_t dev, void (*strat)(struct buf *bp), struct disklabel *lp,
237    struct cpu_disklabel *osdep)
238{
239	struct buf *bp;
240	struct disklabel *dlp;
241	int labelpart;
242	int error = 0;
243
244	labelpart = DISKPART(dev);
245	if (lp->d_partitions[labelpart].p_offset != 0) {
246		if (lp->d_partitions[0].p_offset != 0)
247			return EXDEV;			/* not quite right */
248		labelpart = 0;
249	}
250	bp = geteblk((int)lp->d_secsize);
251	bp->b_dev = makedev(major(dev), DISKMINOR(DISKUNIT(dev), labelpart));
252	bp->b_blkno = LABELSECTOR;
253	bp->b_bcount = lp->d_secsize;
254	bp->b_flags |= B_READ;
255	(*strat)(bp);
256	if ((error = biowait(bp)) != 0)
257		goto done;
258	for (dlp = (struct disklabel *)bp->b_data;
259	    dlp <= (struct disklabel *)
260	      ((char *)bp->b_data + lp->d_secsize - sizeof(*dlp));
261	    dlp = (struct disklabel *)((char *)dlp + sizeof(long))) {
262		if (dlp->d_magic == DISKMAGIC && dlp->d_magic2 == DISKMAGIC &&
263		    dkcksum(dlp) == 0) {
264			*dlp = *lp;
265			bp->b_oflags &= ~(BO_DONE);
266			bp->b_flags &= ~(B_READ);
267			bp->b_flags |= B_WRITE;
268			(*strat)(bp);
269			error = biowait(bp);
270			goto done;
271		}
272	}
273	error = ESRCH;
274done:
275	brelse(bp, 0);
276	return error;
277}
278