xref: /freebsd/sbin/fsck_ffs/setup.c (revision ea825d02749f382c3f7e17f28247f20a48733eab)
1 /*
2  * Copyright (c) 1980, 1986, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if 0
31 #ifndef lint
32 static const char sccsid[] = "@(#)setup.c	8.10 (Berkeley) 5/9/95";
33 #endif /* not lint */
34 #endif
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/param.h>
39 #include <sys/disk.h>
40 #include <sys/stat.h>
41 #define FSTYPENAMES
42 #include <sys/disklabel.h>
43 #include <sys/file.h>
44 #include <sys/sysctl.h>
45 
46 #include <ufs/ufs/dinode.h>
47 #include <ufs/ffs/fs.h>
48 
49 #include <ctype.h>
50 #include <err.h>
51 #include <errno.h>
52 #include <limits.h>
53 #include <stdint.h>
54 #include <string.h>
55 
56 #include "fsck.h"
57 
58 struct bufarea asblk;
59 #define altsblock (*asblk.b_un.b_fs)
60 #define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
61 
62 static int calcsb(char *dev, int devfd, struct fs *fs);
63 static void saverecovery(int readfd, int writefd);
64 static int chkrecovery(int devfd);
65 
66 /*
67  * Read in a superblock finding an alternate if necessary.
68  * Return 1 if successful, 0 if unsuccessful, -1 if file system
69  * is already clean (ckclean and preen mode only).
70  */
71 int
72 setup(char *dev)
73 {
74 	long cg, asked, i, j;
75 	long bmapsize;
76 	struct stat statb;
77 	struct fs proto;
78 	size_t size;
79 
80 	havesb = 0;
81 	fswritefd = -1;
82 	cursnapshot = 0;
83 	if (stat(dev, &statb) < 0) {
84 		printf("Can't stat %s: %s\n", dev, strerror(errno));
85 		if (bkgrdflag) {
86 			unlink(snapname);
87 			bkgrdflag = 0;
88 		}
89 		return (0);
90 	}
91 	if ((statb.st_mode & S_IFMT) != S_IFCHR &&
92 	    (statb.st_mode & S_IFMT) != S_IFBLK) {
93 		if (bkgrdflag != 0 && (statb.st_flags & SF_SNAPSHOT) == 0) {
94 			unlink(snapname);
95 			printf("background fsck lacks a snapshot\n");
96 			exit(EEXIT);
97 		}
98 		if ((statb.st_flags & SF_SNAPSHOT) != 0 && cvtlevel == 0) {
99 			cursnapshot = statb.st_ino;
100 		} else {
101 			if (cvtlevel == 0 ||
102 			    (statb.st_flags & SF_SNAPSHOT) == 0) {
103 				if (preen && bkgrdflag) {
104 					unlink(snapname);
105 					bkgrdflag = 0;
106 				}
107 				pfatal("%s is not a disk device", dev);
108 				if (reply("CONTINUE") == 0) {
109 					if (bkgrdflag) {
110 						unlink(snapname);
111 						bkgrdflag = 0;
112 					}
113 					return (0);
114 				}
115 			} else {
116 				if (bkgrdflag) {
117 					unlink(snapname);
118 					bkgrdflag = 0;
119 				}
120 				pfatal("cannot convert a snapshot");
121 				exit(EEXIT);
122 			}
123 		}
124 	}
125 	if ((fsreadfd = open(dev, O_RDONLY)) < 0) {
126 		if (bkgrdflag) {
127 			unlink(snapname);
128 			bkgrdflag = 0;
129 		}
130 		printf("Can't open %s: %s\n", dev, strerror(errno));
131 		return (0);
132 	}
133 	if (bkgrdflag) {
134 		unlink(snapname);
135 		size = MIBSIZE;
136 		if (sysctlnametomib("vfs.ffs.adjrefcnt", adjrefcnt, &size) < 0||
137 		    sysctlnametomib("vfs.ffs.adjblkcnt", adjblkcnt, &size) < 0||
138 		    sysctlnametomib("vfs.ffs.freefiles", freefiles, &size) < 0||
139 		    sysctlnametomib("vfs.ffs.freedirs", freedirs, &size) < 0 ||
140 		    sysctlnametomib("vfs.ffs.freeblks", freeblks, &size) < 0) {
141 			pfatal("kernel lacks background fsck support\n");
142 			exit(EEXIT);
143 		}
144 		/*
145 		 * When kernel is lack of runtime bgfsck superblock summary
146 		 * adjustment functionality, it does not mean we can not
147 		 * continue, as old kernels will recompute the summary at
148 		 * mount time.  However, it will be an unexpected softupdates
149 		 * inconsistency if it turns out that the summary is still
150 		 * incorrect.  Set a flag so subsequent operation can know
151 		 * this.
152 		 */
153 		bkgrdsumadj = 1;
154 		if (sysctlnametomib("vfs.ffs.adjndir", adjndir, &size) < 0 ||
155 		    sysctlnametomib("vfs.ffs.adjnbfree", adjnbfree, &size) < 0 ||
156 		    sysctlnametomib("vfs.ffs.adjnifree", adjnifree, &size) < 0 ||
157 		    sysctlnametomib("vfs.ffs.adjnffree", adjnffree, &size) < 0 ||
158 		    sysctlnametomib("vfs.ffs.adjnumclusters", adjnumclusters, &size) < 0) {
159 			bkgrdsumadj = 0;
160 			pwarn("kernel lacks runtime superblock summary adjustment support");
161 		}
162 		cmd.version = FFS_CMD_VERSION;
163 		cmd.handle = fsreadfd;
164 		fswritefd = -1;
165 	}
166 	if (preen == 0)
167 		printf("** %s", dev);
168 	if (bkgrdflag == 0 &&
169 	    (nflag || (fswritefd = open(dev, O_WRONLY)) < 0)) {
170 		fswritefd = -1;
171 		if (preen)
172 			pfatal("NO WRITE ACCESS");
173 		printf(" (NO WRITE)");
174 	}
175 	if (preen == 0)
176 		printf("\n");
177 	/*
178 	 * Read in the superblock, looking for alternates if necessary
179 	 */
180 	if (readsb(1) == 0) {
181 		skipclean = 0;
182 		if (bflag || preen || calcsb(dev, fsreadfd, &proto) == 0)
183 			return(0);
184 		if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0)
185 			return (0);
186 		for (cg = 0; cg < proto.fs_ncg; cg++) {
187 			bflag = fsbtodb(&proto, cgsblock(&proto, cg));
188 			if (readsb(0) != 0)
189 				break;
190 		}
191 		if (cg >= proto.fs_ncg) {
192 			printf("%s %s\n%s %s\n%s %s\n",
193 				"SEARCH FOR ALTERNATE SUPER-BLOCK",
194 				"FAILED. YOU MUST USE THE",
195 				"-b OPTION TO FSCK TO SPECIFY THE",
196 				"LOCATION OF AN ALTERNATE",
197 				"SUPER-BLOCK TO SUPPLY NEEDED",
198 				"INFORMATION; SEE fsck_ffs(8).");
199 			bflag = 0;
200 			return(0);
201 		}
202 		pwarn("USING ALTERNATE SUPERBLOCK AT %jd\n", bflag);
203 		bflag = 0;
204 	}
205 	if (skipclean && ckclean && sblock.fs_clean) {
206 		pwarn("FILE SYSTEM CLEAN; SKIPPING CHECKS\n");
207 		return (-1);
208 	}
209 	maxfsblock = sblock.fs_size;
210 	maxino = sblock.fs_ncg * sblock.fs_ipg;
211 	/*
212 	 * Check and potentially fix certain fields in the super block.
213 	 */
214 	if (sblock.fs_optim != FS_OPTTIME && sblock.fs_optim != FS_OPTSPACE) {
215 		pfatal("UNDEFINED OPTIMIZATION IN SUPERBLOCK");
216 		if (reply("SET TO DEFAULT") == 1) {
217 			sblock.fs_optim = FS_OPTTIME;
218 			sbdirty();
219 		}
220 	}
221 	if ((sblock.fs_minfree < 0 || sblock.fs_minfree > 99)) {
222 		pfatal("IMPOSSIBLE MINFREE=%d IN SUPERBLOCK",
223 			sblock.fs_minfree);
224 		if (reply("SET TO DEFAULT") == 1) {
225 			sblock.fs_minfree = 10;
226 			sbdirty();
227 		}
228 	}
229 	if (sblock.fs_magic == FS_UFS1_MAGIC &&
230 	    sblock.fs_old_inodefmt < FS_44INODEFMT) {
231 		pwarn("Format of file system is too old.\n");
232 		pwarn("Must update to modern format using a version of fsck\n");
233 		pfatal("from before 2002 with the command ``fsck -c 2''\n");
234 		exit(EEXIT);
235 	}
236 	if (asblk.b_dirty && !bflag) {
237 		memmove(&altsblock, &sblock, (size_t)sblock.fs_sbsize);
238 		flush(fswritefd, &asblk);
239 	}
240 	if (preen == 0 && yflag == 0 && sblock.fs_magic == FS_UFS2_MAGIC &&
241 	    fswritefd != -1 && chkrecovery(fsreadfd) == 0 &&
242 	    reply("SAVE DATA TO FIND ALTERNATE SUPERBLOCKS") != 0)
243 		saverecovery(fsreadfd, fswritefd);
244 	/*
245 	 * read in the summary info.
246 	 */
247 	asked = 0;
248 	sblock.fs_csp = Calloc(1, sblock.fs_cssize);
249 	if (sblock.fs_csp == NULL) {
250 		printf("cannot alloc %u bytes for cg summary info\n",
251 		    (unsigned)sblock.fs_cssize);
252 		goto badsb;
253 	}
254 	for (i = 0, j = 0; i < sblock.fs_cssize; i += sblock.fs_bsize, j++) {
255 		size = MIN(sblock.fs_cssize - i, sblock.fs_bsize);
256 		readcnt[sblk.b_type]++;
257 		if (blread(fsreadfd, (char *)sblock.fs_csp + i,
258 		    fsbtodb(&sblock, sblock.fs_csaddr + j * sblock.fs_frag),
259 		    size) != 0 && !asked) {
260 			pfatal("BAD SUMMARY INFORMATION");
261 			if (reply("CONTINUE") == 0) {
262 				ckfini(0);
263 				exit(EEXIT);
264 			}
265 			asked++;
266 		}
267 	}
268 	/*
269 	 * allocate and initialize the necessary maps
270 	 */
271 	bmapsize = roundup(howmany(maxfsblock, CHAR_BIT), sizeof(short));
272 	blockmap = Calloc((unsigned)bmapsize, sizeof (char));
273 	if (blockmap == NULL) {
274 		printf("cannot alloc %u bytes for blockmap\n",
275 		    (unsigned)bmapsize);
276 		goto badsb;
277 	}
278 	inostathead = Calloc(sblock.fs_ncg, sizeof(struct inostatlist));
279 	if (inostathead == NULL) {
280 		printf("cannot alloc %u bytes for inostathead\n",
281 		    (unsigned)(sizeof(struct inostatlist) * (sblock.fs_ncg)));
282 		goto badsb;
283 	}
284 	numdirs = MAX(sblock.fs_cstotal.cs_ndir, 128);
285 	dirhash = numdirs;
286 	inplast = 0;
287 	listmax = numdirs + 10;
288 	inpsort = (struct inoinfo **)Calloc(listmax, sizeof(struct inoinfo *));
289 	inphead = (struct inoinfo **)Calloc(numdirs, sizeof(struct inoinfo *));
290 	if (inpsort == NULL || inphead == NULL) {
291 		printf("cannot alloc %ju bytes for inphead\n",
292 		    (uintmax_t)numdirs * sizeof(struct inoinfo *));
293 		goto badsb;
294 	}
295 	bufinit();
296 	if (sblock.fs_flags & FS_DOSOFTDEP)
297 		usedsoftdep = 1;
298 	else
299 		usedsoftdep = 0;
300 	return (1);
301 
302 badsb:
303 	ckfini(0);
304 	return (0);
305 }
306 
307 /*
308  * Possible superblock locations ordered from most to least likely.
309  */
310 static int sblock_try[] = SBLOCKSEARCH;
311 
312 #define BAD_MAGIC_MSG \
313 "The previous newfs operation on this volume did not complete.\n" \
314 "You must complete newfs before mounting this volume.\n"
315 
316 /*
317  * Read in the super block and its summary info.
318  */
319 int
320 readsb(int listerr)
321 {
322 	ufs2_daddr_t super;
323 	int i, bad;
324 
325 	if (bflag) {
326 		super = bflag;
327 		readcnt[sblk.b_type]++;
328 		if ((blread(fsreadfd, (char *)&sblock, super, (long)SBLOCKSIZE)))
329 			return (0);
330 		if (sblock.fs_magic == FS_BAD_MAGIC) {
331 			fprintf(stderr, BAD_MAGIC_MSG);
332 			exit(11);
333 		}
334 		if (sblock.fs_magic != FS_UFS1_MAGIC &&
335 		    sblock.fs_magic != FS_UFS2_MAGIC) {
336 			fprintf(stderr, "%jd is not a file system superblock\n",
337 			    bflag);
338 			return (0);
339 		}
340 	} else {
341 		for (i = 0; sblock_try[i] != -1; i++) {
342 			super = sblock_try[i] / dev_bsize;
343 			readcnt[sblk.b_type]++;
344 			if ((blread(fsreadfd, (char *)&sblock, super,
345 			    (long)SBLOCKSIZE)))
346 				return (0);
347 			if (sblock.fs_magic == FS_BAD_MAGIC) {
348 				fprintf(stderr, BAD_MAGIC_MSG);
349 				exit(11);
350 			}
351 			if ((sblock.fs_magic == FS_UFS1_MAGIC ||
352 			     (sblock.fs_magic == FS_UFS2_MAGIC &&
353 			      sblock.fs_sblockloc == sblock_try[i])) &&
354 			    sblock.fs_ncg >= 1 &&
355 			    sblock.fs_bsize >= MINBSIZE &&
356 			    sblock.fs_sbsize >= roundup(sizeof(struct fs), dev_bsize))
357 				break;
358 		}
359 		if (sblock_try[i] == -1) {
360 			fprintf(stderr, "Cannot find file system superblock\n");
361 			return (0);
362 		}
363 	}
364 	/*
365 	 * Compute block size that the file system is based on,
366 	 * according to fsbtodb, and adjust superblock block number
367 	 * so we can tell if this is an alternate later.
368 	 */
369 	super *= dev_bsize;
370 	dev_bsize = sblock.fs_fsize / fsbtodb(&sblock, 1);
371 	sblk.b_bno = super / dev_bsize;
372 	sblk.b_size = SBLOCKSIZE;
373 	/*
374 	 * Compare all fields that should not differ in alternate super block.
375 	 * When an alternate super-block is specified this check is skipped.
376 	 */
377 	if (bflag)
378 		goto out;
379 	getblk(&asblk, cgsblock(&sblock, sblock.fs_ncg - 1), sblock.fs_sbsize);
380 	if (asblk.b_errs)
381 		return (0);
382 	bad = 0;
383 #define CHK(x, y)				\
384 	if (altsblock.x != sblock.x) {		\
385 		bad++;				\
386 		if (listerr && debug)		\
387 			printf("SUPER BLOCK VS ALTERNATE MISMATCH %s: " y " vs " y "\n", \
388 			    #x, (intmax_t)sblock.x, (intmax_t)altsblock.x); \
389 	}
390 	CHK(fs_sblkno, "%jd");
391 	CHK(fs_cblkno, "%jd");
392 	CHK(fs_iblkno, "%jd");
393 	CHK(fs_dblkno, "%jd");
394 	CHK(fs_ncg, "%jd");
395 	CHK(fs_bsize, "%jd");
396 	CHK(fs_fsize, "%jd");
397 	CHK(fs_frag, "%jd");
398 	CHK(fs_bmask, "%#jx");
399 	CHK(fs_fmask, "%#jx");
400 	CHK(fs_bshift, "%jd");
401 	CHK(fs_fshift, "%jd");
402 	CHK(fs_fragshift, "%jd");
403 	CHK(fs_fsbtodb, "%jd");
404 	CHK(fs_sbsize, "%jd");
405 	CHK(fs_nindir, "%jd");
406 	CHK(fs_inopb, "%jd");
407 	CHK(fs_cssize, "%jd");
408 	CHK(fs_ipg, "%jd");
409 	CHK(fs_fpg, "%jd");
410 	CHK(fs_magic, "%#jx");
411 #undef CHK
412 	if (bad) {
413 		if (listerr == 0)
414 			return (0);
415 		if (preen)
416 			printf("%s: ", cdevname);
417 		printf(
418 		    "VALUES IN SUPER BLOCK LSB=%jd DISAGREE WITH THOSE IN\n"
419 		    "LAST ALTERNATE LSB=%jd\n",
420 		    sblk.b_bno, asblk.b_bno);
421 		if (reply("IGNORE ALTERNATE SUPER BLOCK") == 0)
422 			return (0);
423 	}
424 out:
425 	/*
426 	 * If not yet done, update UFS1 superblock with new wider fields.
427 	 */
428 	if (sblock.fs_magic == FS_UFS1_MAGIC &&
429 	    sblock.fs_maxbsize != sblock.fs_bsize) {
430 		sblock.fs_maxbsize = sblock.fs_bsize;
431 		sblock.fs_time = sblock.fs_old_time;
432 		sblock.fs_size = sblock.fs_old_size;
433 		sblock.fs_dsize = sblock.fs_old_dsize;
434 		sblock.fs_csaddr = sblock.fs_old_csaddr;
435 		sblock.fs_cstotal.cs_ndir = sblock.fs_old_cstotal.cs_ndir;
436 		sblock.fs_cstotal.cs_nbfree = sblock.fs_old_cstotal.cs_nbfree;
437 		sblock.fs_cstotal.cs_nifree = sblock.fs_old_cstotal.cs_nifree;
438 		sblock.fs_cstotal.cs_nffree = sblock.fs_old_cstotal.cs_nffree;
439 	}
440 	havesb = 1;
441 	return (1);
442 }
443 
444 void
445 sblock_init(void)
446 {
447 
448 	fswritefd = -1;
449 	fsmodified = 0;
450 	lfdir = 0;
451 	initbarea(&sblk, BT_SUPERBLK);
452 	initbarea(&asblk, BT_SUPERBLK);
453 	sblk.b_un.b_buf = Malloc(SBLOCKSIZE);
454 	asblk.b_un.b_buf = Malloc(SBLOCKSIZE);
455 	if (sblk.b_un.b_buf == NULL || asblk.b_un.b_buf == NULL)
456 		errx(EEXIT, "cannot allocate space for superblock");
457 	dev_bsize = secsize = DEV_BSIZE;
458 }
459 
460 /*
461  * Calculate a prototype superblock based on information in the boot area.
462  * When done the cgsblock macro can be calculated and the fs_ncg field
463  * can be used. Do NOT attempt to use other macros without verifying that
464  * their needed information is available!
465  */
466 static int
467 calcsb(char *dev, int devfd, struct fs *fs)
468 {
469 	struct fsrecovery *fsr;
470 	char *fsrbuf;
471 	u_int secsize;
472 
473 	/*
474 	 * We need fragments-per-group and the partition-size.
475 	 *
476 	 * Newfs stores these details at the end of the boot block area
477 	 * at the start of the filesystem partition. If they have been
478 	 * overwritten by a boot block, we fail. But usually they are
479 	 * there and we can use them.
480 	 */
481 	if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1)
482 		return (0);
483 	fsrbuf = Malloc(secsize);
484 	if (fsrbuf == NULL)
485 		errx(EEXIT, "calcsb: cannot allocate recovery buffer");
486 	if (blread(devfd, fsrbuf,
487 	    (SBLOCK_UFS2 - secsize) / dev_bsize, secsize) != 0)
488 		return (0);
489 	fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
490 	if (fsr->fsr_magic != FS_UFS2_MAGIC)
491 		return (0);
492 	memset(fs, 0, sizeof(struct fs));
493 	fs->fs_fpg = fsr->fsr_fpg;
494 	fs->fs_fsbtodb = fsr->fsr_fsbtodb;
495 	fs->fs_sblkno = fsr->fsr_sblkno;
496 	fs->fs_magic = fsr->fsr_magic;
497 	fs->fs_ncg = fsr->fsr_ncg;
498 	free(fsrbuf);
499 	return (1);
500 }
501 
502 /*
503  * Check to see if recovery information exists.
504  * Return 1 if it exists or cannot be created.
505  * Return 0 if it does not exist and can be created.
506  */
507 static int
508 chkrecovery(int devfd)
509 {
510 	struct fsrecovery *fsr;
511 	char *fsrbuf;
512 	u_int secsize;
513 
514 	/*
515 	 * Could not determine if backup material exists, so do not
516 	 * offer to create it.
517 	 */
518 	if (ioctl(devfd, DIOCGSECTORSIZE, &secsize) == -1 ||
519 	    (fsrbuf = Malloc(secsize)) == NULL ||
520 	    blread(devfd, fsrbuf, (SBLOCK_UFS2 - secsize) / dev_bsize,
521 	      secsize) != 0)
522 		return (1);
523 	/*
524 	 * Recovery material has already been created, so do not
525 	 * need to create it again.
526 	 */
527 	fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
528 	if (fsr->fsr_magic == FS_UFS2_MAGIC) {
529 		free(fsrbuf);
530 		return (1);
531 	}
532 	/*
533 	 * Recovery material has not been created and can be if desired.
534 	 */
535 	free(fsrbuf);
536 	return (0);
537 }
538 
539 /*
540  * Read the last sector of the boot block, replace the last
541  * 20 bytes with the recovery information, then write it back.
542  * The recovery information only works for UFS2 filesystems.
543  */
544 static void
545 saverecovery(int readfd, int writefd)
546 {
547 	struct fsrecovery *fsr;
548 	char *fsrbuf;
549 	u_int secsize;
550 
551 	if (sblock.fs_magic != FS_UFS2_MAGIC ||
552 	    ioctl(readfd, DIOCGSECTORSIZE, &secsize) == -1 ||
553 	    (fsrbuf = Malloc(secsize)) == NULL ||
554 	    blread(readfd, fsrbuf, (SBLOCK_UFS2 - secsize) / dev_bsize,
555 	      secsize) != 0) {
556 		printf("RECOVERY DATA COULD NOT BE CREATED\n");
557 		return;
558 	}
559 	fsr = (struct fsrecovery *)&fsrbuf[secsize - sizeof *fsr];
560 	fsr->fsr_magic = sblock.fs_magic;
561 	fsr->fsr_fpg = sblock.fs_fpg;
562 	fsr->fsr_fsbtodb = sblock.fs_fsbtodb;
563 	fsr->fsr_sblkno = sblock.fs_sblkno;
564 	fsr->fsr_ncg = sblock.fs_ncg;
565 	blwrite(writefd, fsrbuf, (SBLOCK_UFS2 - secsize) / secsize, secsize);
566 	free(fsrbuf);
567 }
568