xref: /netbsd-src/sbin/fsck_ext2fs/setup.c (revision 95d875fb90b1458e4f1de6950286ddcd6644bc61)
1 /*	$NetBSD: setup.c,v 1.10 1999/02/17 13:11:19 bouyer Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 Manuel Bouyer.
5  * Copyright (c) 1980, 1986, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *	notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *	notice, this list of conditions and the following disclaimer in the
15  *	documentation and/or other materials provided with the distribution.
16  * 3. All advertising materials mentioning features or use of this software
17  *	must display the following acknowledgement:
18  *	This product includes software developed by the University of
19  *	California, Berkeley and its contributors.
20  * 4. Neither the name of the University nor the names of its contributors
21  *	may be used to endorse or promote products derived from this software
22  *	without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34  * SUCH DAMAGE.
35  */
36 
37 #include <sys/cdefs.h>
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)setup.c	8.5 (Berkeley) 11/23/94";
41 #else
42 __RCSID("$NetBSD: setup.c,v 1.10 1999/02/17 13:11:19 bouyer Exp $");
43 #endif
44 #endif /* not lint */
45 
46 #define FSTYPENAMES
47 #include <sys/param.h>
48 #include <sys/time.h>
49 #include <ufs/ext2fs/ext2fs_dinode.h>
50 #include <ufs/ext2fs/ext2fs.h>
51 #include <sys/stat.h>
52 #include <sys/ioctl.h>
53 #include <sys/disklabel.h>
54 #include <sys/file.h>
55 
56 #include <errno.h>
57 #include <stdio.h>
58 #include <stdlib.h>
59 #include <string.h>
60 #include <ctype.h>
61 
62 #include "fsck.h"
63 #include "extern.h"
64 #include "fsutil.h"
65 
66 #define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
67 
68 void badsb __P((int, char *));
69 int calcsb __P((const char *, int, struct m_ext2fs *));
70 static struct disklabel *getdisklabel __P((const char *, int));
71 static int readsb __P((int));
72 
73 int
74 setup(dev)
75 	const char *dev;
76 {
77 	long cg, asked, i;
78 	long bmapsize;
79 	struct disklabel *lp;
80 	off_t sizepb;
81 	struct stat statb;
82 	struct m_ext2fs proto;
83 	int doskipclean;
84 	u_int64_t maxfilesize;
85 
86 	havesb = 0;
87 	fswritefd = -1;
88 	doskipclean = skipclean;
89 	if (stat(dev, &statb) < 0) {
90 		printf("Can't stat %s: %s\n", dev, strerror(errno));
91 		return (0);
92 	}
93 	if (!S_ISCHR(statb.st_mode)) {
94 		pfatal("%s is not a character device", dev);
95 		if (reply("CONTINUE") == 0)
96 			return (0);
97 	}
98 	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
99 		printf("Can't open %s: %s\n", dev, strerror(errno));
100 		return (0);
101 	}
102 	if (preen == 0)
103 		printf("** %s", dev);
104 	if (nflag || (fswritefd = open(dev, O_WRONLY)) < 0) {
105 		fswritefd = -1;
106 		if (preen)
107 			pfatal("NO WRITE ACCESS");
108 		printf(" (NO WRITE)");
109 	}
110 	if (preen == 0)
111 		printf("\n");
112 	fsmodified = 0;
113 	lfdir = 0;
114 	initbarea(&sblk);
115 	initbarea(&asblk);
116 	sblk.b_un.b_buf = malloc(SBSIZE);
117 	asblk.b_un.b_buf = malloc(SBSIZE);
118 	if (sblk.b_un.b_buf == NULL || asblk.b_un.b_buf == NULL)
119 		errexit("cannot allocate space for superblock\n");
120 	if ((lp = getdisklabel((char *)NULL, fsreadfd)) != NULL)
121 		dev_bsize = secsize = lp->d_secsize;
122 	else
123 		dev_bsize = secsize = DEV_BSIZE;
124 	/*
125 	 * Read in the superblock, looking for alternates if necessary
126 	 */
127 	if (readsb(1) == 0) {
128 		if (bflag || preen || calcsb(dev, fsreadfd, &proto) == 0)
129 			return(0);
130 		if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
131 			return (0);
132 		for (cg = 1; cg < proto.e2fs_ncg; cg++) {
133 			bflag = fsbtodb(&proto,
134 				cg * proto.e2fs.e2fs_bpg + proto.e2fs.e2fs_first_dblock);
135 			if (readsb(0) != 0)
136 				break;
137 		}
138 		if (cg >= proto.e2fs_ncg) {
139 			printf("%s %s\n%s %s\n%s %s\n",
140 				"SEARCH FOR ALTERNATE SUPER-BLOCK",
141 				"FAILED. YOU MUST USE THE",
142 				"-b OPTION TO FSCK_FFS TO SPECIFY THE",
143 				"LOCATION OF AN ALTERNATE",
144 				"SUPER-BLOCK TO SUPPLY NEEDED",
145 				"INFORMATION; SEE fsck_ext2fs(8).");
146 			return(0);
147 		}
148 		doskipclean = 0;
149 		pwarn("USING ALTERNATE SUPERBLOCK AT %d\n", bflag);
150 	}
151 	if (debug)
152 		printf("state = %d\n", sblock.e2fs.e2fs_state);
153 	if (sblock.e2fs.e2fs_state == E2FS_ISCLEAN) {
154 		if (doskipclean) {
155 			pwarn("%sile system is clean; not checking\n",
156 				preen ? "f" : "** F");
157 			return (-1);
158 		}
159 		if (!preen)
160 			pwarn("** File system is already clean\n");
161 	}
162 	maxfsblock = sblock.e2fs.e2fs_bcount;
163 	maxino = sblock.e2fs_ncg * sblock.e2fs.e2fs_ipg;
164 	sizepb = sblock.e2fs_bsize;
165 	maxfilesize = sblock.e2fs_bsize * NDADDR - 1;
166 	for (i = 0; i < NIADDR; i++) {
167 		sizepb *= NINDIR(&sblock);
168 		maxfilesize += sizepb;
169 	}
170 	/*
171 	 * Check and potentially fix certain fields in the super block.
172 	 */
173 	if ((sblock.e2fs.e2fs_rbcount < 0) ||
174 			(sblock.e2fs.e2fs_rbcount > sblock.e2fs.e2fs_bcount)) {
175 		pfatal("IMPOSSIBLE RESERVED BLOCK COUNT=%d IN SUPERBLOCK",
176 			sblock.e2fs.e2fs_rbcount);
177 		if (reply("SET TO DEFAULT") == 1) {
178 			sblock.e2fs.e2fs_rbcount = sblock.e2fs.e2fs_bcount * 0.1;
179 			sbdirty();
180 			dirty(&asblk);
181 		}
182 	}
183 	if (sblock.e2fs.e2fs_bpg != sblock.e2fs.e2fs_fpg) {
184 		pfatal("WRONG FPG=%d (BPG=%d) IN SUPERBLOCK",
185 			sblock.e2fs.e2fs_fpg, sblock.e2fs.e2fs_bpg);
186 		return 0;
187 	}
188 	if (asblk.b_dirty && !bflag) {
189 		copyback_sb(&asblk);
190 		flush(fswritefd, &asblk);
191 	}
192 	/*
193 	 * read in the summary info.
194 	 */
195 
196 	sblock.e2fs_gd = malloc(sblock.e2fs_ngdb * sblock.e2fs_bsize);
197 	if (sblock.e2fs_gd == NULL)
198 		errexit("out of memory\n");
199 	asked = 0;
200 	for (i=0; i < sblock.e2fs_ngdb; i++) {
201 		if (bread(fsreadfd,(char *)
202 			&sblock.e2fs_gd[i* sblock.e2fs_bsize / sizeof(struct ext2_gd)],
203 			fsbtodb(&sblock, ((sblock.e2fs_bsize>1024)?0:1)+i+1),
204 			sblock.e2fs_bsize) != 0 && !asked) {
205 			pfatal("BAD SUMMARY INFORMATION");
206 			if (reply("CONTINUE") == 0)
207 				errexit("%s\n", "");
208 			asked++;
209 		}
210 	}
211 	/*
212 	 * allocate and initialize the necessary maps
213 	 */
214 	bmapsize = roundup(howmany(maxfsblock, NBBY), sizeof(int16_t));
215 	blockmap = calloc((unsigned)bmapsize, sizeof (char));
216 	if (blockmap == NULL) {
217 		printf("cannot alloc %u bytes for blockmap\n",
218 			(unsigned)bmapsize);
219 		goto badsblabel;
220 	}
221 	statemap = calloc((unsigned)(maxino + 2), sizeof(char));
222 	if (statemap == NULL) {
223 		printf("cannot alloc %u bytes for statemap\n",
224 			(unsigned)(maxino + 1));
225 		goto badsblabel;
226 	}
227 	lncntp = (int16_t *)calloc((unsigned)(maxino + 1), sizeof(int16_t));
228 	if (lncntp == NULL) {
229 		printf("cannot alloc %u bytes for lncntp\n",
230 			(unsigned)((maxino + 1) * sizeof(int16_t)));
231 		goto badsblabel;
232 	}
233 	for (numdirs = 0, cg = 0; cg < sblock.e2fs_ncg; cg++) {
234 		numdirs += fs2h16(sblock.e2fs_gd[cg].ext2bgd_ndirs);
235 	}
236 	inplast = 0;
237 	listmax = numdirs + 10;
238 	inpsort = (struct inoinfo **)calloc((unsigned)listmax,
239 		sizeof(struct inoinfo *));
240 	inphead = (struct inoinfo **)calloc((unsigned)numdirs,
241 		sizeof(struct inoinfo *));
242 	if (inpsort == NULL || inphead == NULL) {
243 		printf("cannot alloc %u bytes for inphead\n",
244 			(unsigned)(numdirs * sizeof(struct inoinfo *)));
245 		goto badsblabel;
246 	}
247 	bufinit();
248 	return (1);
249 
250 badsblabel:
251 	ckfini(0);
252 	return (0);
253 }
254 
255 /*
256  * Read in the super block and its summary info, convert to host byte order.
257  */
258 static int
259 readsb(listerr)
260 	int listerr;
261 {
262 	daddr_t super = bflag ? bflag : SBOFF / dev_bsize;
263 
264 	if (bread(fsreadfd, (char *)sblk.b_un.b_fs, super, (long)SBSIZE) != 0)
265 		return (0);
266 	sblk.b_bno = super;
267 	sblk.b_size = SBSIZE;
268 
269 	/* Copy the superblock in memory */
270 	sblock.e2fs.e2fs_icount = fs2h32(sblk.b_un.b_fs->e2fs_icount);
271 	sblock.e2fs.e2fs_bcount = fs2h32(sblk.b_un.b_fs->e2fs_bcount);
272 	sblock.e2fs.e2fs_rbcount = fs2h32(sblk.b_un.b_fs->e2fs_rbcount);
273 	sblock.e2fs.e2fs_fbcount = fs2h32(sblk.b_un.b_fs->e2fs_fbcount);
274 	sblock.e2fs.e2fs_ficount = fs2h32(sblk.b_un.b_fs->e2fs_ficount);
275 	sblock.e2fs.e2fs_first_dblock = fs2h32(sblk.b_un.b_fs->e2fs_first_dblock);
276 	sblock.e2fs.e2fs_log_bsize = fs2h32(sblk.b_un.b_fs->e2fs_log_bsize);
277 	sblock.e2fs.e2fs_fsize = fs2h32(sblk.b_un.b_fs->e2fs_fsize);
278 	sblock.e2fs.e2fs_bpg = fs2h32(sblk.b_un.b_fs->e2fs_bpg);
279 	sblock.e2fs.e2fs_fpg = fs2h32(sblk.b_un.b_fs->e2fs_fpg);
280 	sblock.e2fs.e2fs_ipg = fs2h32(sblk.b_un.b_fs->e2fs_ipg);
281 	sblock.e2fs.e2fs_mtime = fs2h32(sblk.b_un.b_fs->e2fs_mtime);
282 	sblock.e2fs.e2fs_wtime = fs2h32(sblk.b_un.b_fs->e2fs_wtime);
283 	sblock.e2fs.e2fs_lastfsck = fs2h32(sblk.b_un.b_fs->e2fs_lastfsck);
284 	sblock.e2fs.e2fs_fsckintv = fs2h32(sblk.b_un.b_fs->e2fs_fsckintv);
285 	sblock.e2fs.e2fs_creator = fs2h32(sblk.b_un.b_fs->e2fs_creator);
286 	sblock.e2fs.e2fs_rev = fs2h32(sblk.b_un.b_fs->e2fs_rev);
287 	sblock.e2fs.e2fs_mnt_count = fs2h16(sblk.b_un.b_fs->e2fs_mnt_count);
288 	sblock.e2fs.e2fs_max_mnt_count = fs2h16(sblk.b_un.b_fs->e2fs_max_mnt_count);
289 	sblock.e2fs.e2fs_magic = fs2h16(sblk.b_un.b_fs->e2fs_magic);
290 	sblock.e2fs.e2fs_state = fs2h16(sblk.b_un.b_fs->e2fs_state);
291 	sblock.e2fs.e2fs_beh = fs2h16(sblk.b_un.b_fs->e2fs_beh);
292 	sblock.e2fs.e2fs_ruid = fs2h16(sblk.b_un.b_fs->e2fs_ruid);
293 	sblock.e2fs.e2fs_rgid = fs2h16(sblk.b_un.b_fs->e2fs_rgid);
294 
295 	/*
296 	 * run a few consistency checks of the super block
297 	 */
298 	if (sblock.e2fs.e2fs_magic != E2FS_MAGIC) {
299 		badsb(listerr, "MAGIC NUMBER WRONG"); return (0);
300 	}
301 	if (sblock.e2fs.e2fs_log_bsize > 2) {
302 		badsb(listerr, "BAD LOG_BSIZE"); return (0);
303 	}
304 
305 	/* compute the dynamic fields of the in-memory sb */
306 	/* compute dynamic sb infos */
307 	sblock.e2fs_ncg =
308 		howmany(sblock.e2fs.e2fs_bcount - sblock.e2fs.e2fs_first_dblock,
309 		sblock.e2fs.e2fs_bpg);
310 	/* XXX assume hw bsize = 512 */
311 	sblock.e2fs_fsbtodb = sblock.e2fs.e2fs_log_bsize + 1;
312 	sblock.e2fs_bsize = 1024 << sblock.e2fs.e2fs_log_bsize;
313 	sblock.e2fs_bshift = LOG_MINBSIZE + sblock.e2fs.e2fs_log_bsize;
314 	sblock.e2fs_qbmask = sblock.e2fs_bsize - 1;
315 	sblock.e2fs_bmask = ~sblock.e2fs_qbmask;
316 	sblock.e2fs_ngdb = howmany(sblock.e2fs_ncg,
317 		sblock.e2fs_bsize / sizeof(struct ext2_gd));
318 	sblock.e2fs_ipb = sblock.e2fs_bsize / sizeof(struct ext2fs_dinode);
319 	sblock.e2fs_itpg = sblock.e2fs.e2fs_ipg/sblock.e2fs_ipb;
320 
321 	cgoverhead =	1 /* super block */ +
322 					sblock.e2fs_ngdb +
323 					1 /* block bitmap */ +
324 					1 /* inode bitmap */ +
325 					sblock.e2fs_itpg;
326 
327 	if (debug) /* DDD */
328 		printf("cg overhead %d blocks \n", cgoverhead);
329 	/*
330 	 * Compute block size that the filesystem is based on,
331 	 * according to fsbtodb, and adjust superblock block number
332 	 * so we can tell if this is an alternate later.
333 	 */
334 	super *= dev_bsize;
335 	dev_bsize = sblock.e2fs_bsize / fsbtodb(&sblock, 1);
336 	sblk.b_bno = super / dev_bsize;
337 
338 	getblk(&asblk, 1 * sblock.e2fs.e2fs_bpg + sblock.e2fs.e2fs_first_dblock,
339 		(long)SBSIZE);
340 	if (asblk.b_errs)
341 		return (0);
342 	if (bflag) {
343 		havesb = 1;
344 		return (1);
345 	}
346 
347 	/*
348 	 * Set all possible fields that could differ, then do check
349 	 * of whole super block against an alternate super block.
350 	 * When an alternate super-block is specified this check is skipped.
351 	 */
352 	asblk.b_un.b_fs->e2fs_rbcount = sblk.b_un.b_fs->e2fs_rbcount;
353 	asblk.b_un.b_fs->e2fs_fbcount = sblk.b_un.b_fs->e2fs_fbcount;
354 	asblk.b_un.b_fs->e2fs_ficount = sblk.b_un.b_fs->e2fs_ficount;
355 	asblk.b_un.b_fs->e2fs_mtime = sblk.b_un.b_fs->e2fs_mtime;
356 	asblk.b_un.b_fs->e2fs_wtime = sblk.b_un.b_fs->e2fs_wtime;
357 	asblk.b_un.b_fs->e2fs_mnt_count = sblk.b_un.b_fs->e2fs_mnt_count;
358 	asblk.b_un.b_fs->e2fs_max_mnt_count = sblk.b_un.b_fs->e2fs_max_mnt_count;
359 	asblk.b_un.b_fs->e2fs_state = sblk.b_un.b_fs->e2fs_state;
360 	asblk.b_un.b_fs->e2fs_beh = sblk.b_un.b_fs->e2fs_beh;
361 	asblk.b_un.b_fs->e2fs_lastfsck = sblk.b_un.b_fs->e2fs_lastfsck;
362 	asblk.b_un.b_fs->e2fs_fsckintv = sblk.b_un.b_fs->e2fs_fsckintv;
363 	asblk.b_un.b_fs->e2fs_ruid = sblk.b_un.b_fs->e2fs_ruid;
364 	asblk.b_un.b_fs->e2fs_rgid = sblk.b_un.b_fs->e2fs_rgid;
365 	asblk.b_un.b_fs->e2fs_block_group_nr =
366 	    sblk.b_un.b_fs->e2fs_block_group_nr;
367 	if (sblk.b_un.b_fs->e2fs_features_compat != 0 ||
368 	    sblk.b_un.b_fs->e2fs_features_incompat != 0 ||
369 	    sblk.b_un.b_fs->e2fs_features_compat_ro != 0) {
370 		if (debug) {
371 			printf("compat 0x%08x, incompat 0x%08x, compat_ro "
372 			    "0x%08x\n",
373 			    sblk.b_un.b_fs->e2fs_features_compat,
374 			    sblk.b_un.b_fs->e2fs_features_incompat,
375 			    sblk.b_un.b_fs->e2fs_features_compat_ro);
376 		}
377 		badsb(listerr,"UNKNOWN FEATURE BITS IN SUPER BLOCK");
378 		return 0;
379 	}
380 	if (memcmp(sblk.b_un.b_fs, asblk.b_un.b_fs, SBSIZE)) {
381 		if (debug) {
382 			u_int32_t *nlp, *olp, *endlp;
383 
384 			printf("superblock mismatches\n");
385 			nlp = (u_int32_t *)asblk.b_un.b_fs;
386 			olp = (u_int32_t *)sblk.b_un.b_fs;
387 			endlp = olp + (SBSIZE / sizeof *olp);
388 			for ( ; olp < endlp; olp++, nlp++) {
389 				if (*olp == *nlp)
390 					continue;
391 				printf("offset %ld, original %ld, alternate %ld\n",
392 					(long)(olp - (u_int32_t *)sblk.b_un.b_fs),
393 					(long)fs2h32(*olp),
394 					(long)fs2h32(*nlp));
395 			}
396 		}
397 		badsb(listerr,
398 		"VALUES IN SUPER BLOCK DISAGREE WITH THOSE IN FIRST ALTERNATE");
399 		return (0);
400 	}
401 	havesb = 1;
402 	return (1);
403 }
404 
405 void
406 copyback_sb(bp)
407 	struct bufarea *bp;
408 {
409 	/* Copy the in-memory superblock back to buffer */
410 	bp->b_un.b_fs->e2fs_icount = fs2h32(sblock.e2fs.e2fs_icount);
411 	bp->b_un.b_fs->e2fs_bcount = fs2h32(sblock.e2fs.e2fs_bcount);
412 	bp->b_un.b_fs->e2fs_rbcount = fs2h32(sblock.e2fs.e2fs_rbcount);
413 	bp->b_un.b_fs->e2fs_fbcount = fs2h32(sblock.e2fs.e2fs_fbcount);
414 	bp->b_un.b_fs->e2fs_ficount = fs2h32(sblock.e2fs.e2fs_ficount);
415 	bp->b_un.b_fs->e2fs_first_dblock =
416 								fs2h32(sblock.e2fs.e2fs_first_dblock);
417 	bp->b_un.b_fs->e2fs_log_bsize = fs2h32(sblock.e2fs.e2fs_log_bsize);
418 	bp->b_un.b_fs->e2fs_fsize = fs2h32(sblock.e2fs.e2fs_fsize);
419 	bp->b_un.b_fs->e2fs_bpg = fs2h32(sblock.e2fs.e2fs_bpg);
420 	bp->b_un.b_fs->e2fs_fpg = fs2h32(sblock.e2fs.e2fs_fpg);
421 	bp->b_un.b_fs->e2fs_ipg = fs2h32(sblock.e2fs.e2fs_ipg);
422 	bp->b_un.b_fs->e2fs_mtime = fs2h32(sblock.e2fs.e2fs_mtime);
423 	bp->b_un.b_fs->e2fs_wtime = fs2h32(sblock.e2fs.e2fs_wtime);
424 	bp->b_un.b_fs->e2fs_lastfsck = fs2h32(sblock.e2fs.e2fs_lastfsck);
425 	bp->b_un.b_fs->e2fs_fsckintv = fs2h32(sblock.e2fs.e2fs_fsckintv);
426 	bp->b_un.b_fs->e2fs_creator = fs2h32(sblock.e2fs.e2fs_creator);
427 	bp->b_un.b_fs->e2fs_rev = fs2h32(sblock.e2fs.e2fs_rev);
428 	bp->b_un.b_fs->e2fs_mnt_count = fs2h16(sblock.e2fs.e2fs_mnt_count);
429 	bp->b_un.b_fs->e2fs_max_mnt_count =
430 								fs2h16(sblock.e2fs.e2fs_max_mnt_count);
431 	bp->b_un.b_fs->e2fs_magic = fs2h16(sblock.e2fs.e2fs_magic);
432 	bp->b_un.b_fs->e2fs_state = fs2h16(sblock.e2fs.e2fs_state);
433 	bp->b_un.b_fs->e2fs_beh = fs2h16(sblock.e2fs.e2fs_beh);
434 	bp->b_un.b_fs->e2fs_ruid = fs2h16(sblock.e2fs.e2fs_ruid);
435 	bp->b_un.b_fs->e2fs_rgid = fs2h16(sblock.e2fs.e2fs_rgid);
436 }
437 
438 void
439 badsb(listerr, s)
440 	int listerr;
441 	char *s;
442 {
443 
444 	if (!listerr)
445 		return;
446 	if (preen)
447 		printf("%s: ", cdevname());
448 	pfatal("BAD SUPER BLOCK: %s\n", s);
449 }
450 
451 /*
452  * Calculate a prototype superblock based on information in the disk label.
453  * When done the cgsblock macro can be calculated and the fs_ncg field
454  * can be used. Do NOT attempt to use other macros without verifying that
455  * their needed information is available!
456  */
457 
458 int
459 calcsb(dev, devfd, fs)
460 	const char *dev;
461 	int devfd;
462 	struct m_ext2fs *fs;
463 {
464 	struct disklabel *lp;
465 	struct partition *pp;
466 	char *cp;
467 
468 	cp = strchr(dev, '\0') - 1;
469 	if ((cp == (char *)-1 || (*cp < 'a' || *cp > 'h')) && !isdigit(*cp)) {
470 		pfatal("%s: CANNOT FIGURE OUT FILE SYSTEM PARTITION\n", dev);
471 		return (0);
472 	}
473 	lp = getdisklabel(dev, devfd);
474 	if (isdigit(*cp))
475 		pp = &lp->d_partitions[0];
476 	else
477 		pp = &lp->d_partitions[*cp - 'a'];
478 	if (pp->p_fstype != FS_EX2FS) {
479 		pfatal("%s: NOT LABELED AS A EXT2 FILE SYSTEM (%s)\n",
480 			dev, pp->p_fstype < FSMAXTYPES ?
481 			fstypenames[pp->p_fstype] : "unknown");
482 		return (0);
483 	}
484 	memset(fs, 0, sizeof(struct m_ext2fs));
485 	fs->e2fs_bsize = pp->p_fsize;
486 	fs->e2fs.e2fs_log_bsize = pp->p_fsize / 1024;
487 	fs->e2fs.e2fs_bcount = (pp->p_size * DEV_BSIZE) / fs->e2fs_bsize;
488 	fs->e2fs.e2fs_first_dblock = (fs->e2fs.e2fs_log_bsize == 0) ? 1 : 0;
489 	fs->e2fs.e2fs_bpg = fs->e2fs_bsize * NBBY;
490 	fs->e2fs_bshift = LOG_MINBSIZE + fs->e2fs.e2fs_log_bsize;
491 	fs->e2fs_qbmask = fs->e2fs_bsize - 1;
492 	fs->e2fs_bmask = ~fs->e2fs_qbmask;
493 	fs->e2fs_ncg =
494 		howmany(fs->e2fs.e2fs_bcount - fs->e2fs.e2fs_first_dblock,
495 		fs->e2fs.e2fs_bpg);
496 	fs->e2fs_fsbtodb = fs->e2fs.e2fs_log_bsize + 1;
497 	fs->e2fs_ngdb = howmany(fs->e2fs_ncg,
498 		fs->e2fs_bsize / sizeof(struct ext2_gd));
499 
500 	return (1);
501 }
502 
503 static struct disklabel *
504 getdisklabel(s, fd)
505 	const char *s;
506 	int	fd;
507 {
508 	static struct disklabel lab;
509 
510 	if (ioctl(fd, DIOCGDINFO, (char *)&lab) < 0) {
511 		if (s == NULL)
512 			return ((struct disklabel *)NULL);
513 		pwarn("ioctl (GCINFO): %s\n", strerror(errno));
514 		errexit("%s: can't read disk label\n", s);
515 	}
516 	return (&lab);
517 }
518