xref: /freebsd/sbin/growfs/growfs.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
1 /*-
2  * SPDX-License-Identifier: BSD-4-Clause
3  *
4  * Copyright (c) 1980, 1989, 1993 The Regents of the University of California.
5  * Copyright (c) 2000 Christoph Herrmann, Thomas-Henning von Kamptz
6  * Copyright (c) 2012 The FreeBSD Foundation
7  * All rights reserved.
8  *
9  * This code is derived from software contributed to Berkeley by
10  * Christoph Herrmann and Thomas-Henning von Kamptz, Munich and Frankfurt.
11  *
12  * Portions of this software were developed by Edward Tomasz Napierala
13  * under sponsorship from the FreeBSD Foundation.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  * 3. All advertising materials mentioning features or use of this software
24  *    must display the following acknowledgment:
25  *      This product includes software developed by the University of
26  *      California, Berkeley and its contributors, as well as Christoph
27  *      Herrmann and Thomas-Henning von Kamptz.
28  * 4. Neither the name of the University nor the names of its contributors
29  *    may be used to endorse or promote products derived from this software
30  *    without specific prior written permission.
31  *
32  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
33  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
34  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
35  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
36  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
37  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
38  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
39  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
40  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
41  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
42  * SUCH DAMAGE.
43  *
44  * $TSHeader: src/sbin/growfs/growfs.c,v 1.5 2000/12/12 19:31:00 tomsoft Exp $
45  *
46  */
47 
48 #include <sys/param.h>
49 #include <sys/ioctl.h>
50 #include <sys/stat.h>
51 #include <sys/disk.h>
52 #include <sys/ucred.h>
53 #include <sys/mount.h>
54 
55 #include <stdio.h>
56 #include <paths.h>
57 #include <ctype.h>
58 #include <err.h>
59 #include <errno.h>
60 #include <fcntl.h>
61 #include <fstab.h>
62 #include <inttypes.h>
63 #include <limits.h>
64 #include <mntopts.h>
65 #include <paths.h>
66 #include <stdlib.h>
67 #include <stdint.h>
68 #include <string.h>
69 #include <time.h>
70 #include <unistd.h>
71 #include <ufs/ufs/dinode.h>
72 #include <ufs/ffs/fs.h>
73 #include <libutil.h>
74 #include <libufs.h>
75 
76 #include "debug.h"
77 
78 #ifdef FS_DEBUG
79 int	_dbg_lvl_ = (DL_INFO);	/* DL_TRC */
80 #endif /* FS_DEBUG */
81 
82 static union {
83 	struct fs	fs;
84 	char		pad[SBLOCKSIZE];
85 } fsun1, fsun2;
86 #define	sblock	fsun1.fs	/* the new superblock */
87 #define	osblock	fsun2.fs	/* the old superblock */
88 
89 static union {
90 	struct cg	cg;
91 	char		pad[MAXBSIZE];
92 } cgun1, cgun2;
93 #define	acg	cgun1.cg	/* a cylinder cgroup (new) */
94 #define	aocg	cgun2.cg	/* an old cylinder group */
95 
96 static struct csum	*fscs;	/* cylinder summary */
97 
98 static void	growfs(int, int, unsigned int);
99 static void	rdfs(ufs2_daddr_t, size_t, void *, int);
100 static void	wtfs(ufs2_daddr_t, size_t, void *, int, unsigned int);
101 static int	charsperline(void);
102 static void	usage(void);
103 static int	isblock(struct fs *, unsigned char *, int);
104 static void	clrblock(struct fs *, unsigned char *, int);
105 static void	setblock(struct fs *, unsigned char *, int);
106 static void	initcg(int, time_t, int, unsigned int);
107 static void	updjcg(int, time_t, int, int, unsigned int);
108 static void	updcsloc(time_t, int, int, unsigned int);
109 static void	frag_adjust(ufs2_daddr_t, int);
110 static void	updclst(int);
111 static void	cgckhash(struct cg *);
112 
113 /*
114  * Here we actually start growing the file system. We basically read the
115  * cylinder summary from the first cylinder group as we want to update
116  * this on the fly during our various operations. First we handle the
117  * changes in the former last cylinder group. Afterwards we create all new
118  * cylinder groups.  Now we handle the cylinder group containing the
119  * cylinder summary which might result in a relocation of the whole
120  * structure.  In the end we write back the updated cylinder summary, the
121  * new superblock, and slightly patched versions of the super block
122  * copies.
123  */
124 static void
125 growfs(int fsi, int fso, unsigned int Nflag)
126 {
127 	DBG_FUNC("growfs")
128 	time_t modtime;
129 	uint cylno;
130 	int i, j, width;
131 	char tmpbuf[100];
132 
133 	DBG_ENTER;
134 
135 	time(&modtime);
136 
137 	/*
138 	 * Get the cylinder summary into the memory.
139 	 */
140 	fscs = (struct csum *)calloc((size_t)1, (size_t)sblock.fs_cssize);
141 	if (fscs == NULL)
142 		errx(3, "calloc failed");
143 	memcpy(fscs, osblock.fs_csp, osblock.fs_cssize);
144 	free(osblock.fs_csp);
145 	osblock.fs_csp = NULL;
146 	sblock.fs_csp = fscs;
147 
148 #ifdef FS_DEBUG
149 	{
150 		struct csum *dbg_csp;
151 		u_int32_t dbg_csc;
152 		char dbg_line[80];
153 
154 		dbg_csp = fscs;
155 
156 		for (dbg_csc = 0; dbg_csc < osblock.fs_ncg; dbg_csc++) {
157 			snprintf(dbg_line, sizeof(dbg_line),
158 			    "%d. old csum in old location", dbg_csc);
159 			DBG_DUMP_CSUM(&osblock, dbg_line, dbg_csp++);
160 		}
161 	}
162 #endif /* FS_DEBUG */
163 	DBG_PRINT0("fscs read\n");
164 
165 	/*
166 	 * Do all needed changes in the former last cylinder group.
167 	 */
168 	updjcg(osblock.fs_ncg - 1, modtime, fsi, fso, Nflag);
169 
170 	/*
171 	 * Dump out summary information about file system.
172 	 */
173 #ifdef FS_DEBUG
174 #define B2MBFACTOR (1 / (1024.0 * 1024.0))
175 	printf("growfs: %.1fMB (%jd sectors) block size %d, fragment size %d\n",
176 	    (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
177 	    (intmax_t)fsbtodb(&sblock, sblock.fs_size), sblock.fs_bsize,
178 	    sblock.fs_fsize);
179 	printf("\tusing %d cylinder groups of %.2fMB, %d blks, %d inodes.\n",
180 	    sblock.fs_ncg, (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
181 	    sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
182 	if (sblock.fs_flags & FS_DOSOFTDEP)
183 		printf("\twith soft updates\n");
184 #undef B2MBFACTOR
185 #endif /* FS_DEBUG */
186 
187 	/*
188 	 * Now build the cylinders group blocks and
189 	 * then print out indices of cylinder groups.
190 	 */
191 	printf("super-block backups (for fsck_ffs -b #) at:\n");
192 	i = 0;
193 	width = charsperline();
194 
195 	/*
196 	 * Iterate for only the new cylinder groups.
197 	 */
198 	for (cylno = osblock.fs_ncg; cylno < sblock.fs_ncg; cylno++) {
199 		initcg(cylno, modtime, fso, Nflag);
200 		j = sprintf(tmpbuf, " %jd%s",
201 		    (intmax_t)fsbtodb(&sblock, cgsblock(&sblock, cylno)),
202 		    cylno < (sblock.fs_ncg - 1) ? "," : "" );
203 		if (i + j >= width) {
204 			printf("\n");
205 			i = 0;
206 		}
207 		i += j;
208 		printf("%s", tmpbuf);
209 		fflush(stdout);
210 	}
211 	printf("\n");
212 
213 	/*
214 	 * Do all needed changes in the first cylinder group.
215 	 * allocate blocks in new location
216 	 */
217 	updcsloc(modtime, fsi, fso, Nflag);
218 
219 	/*
220 	 * Clean up the dynamic fields in our superblock.
221 	 *
222 	 * XXX
223 	 * The following fields are currently distributed from the superblock
224 	 * to the copies:
225 	 *     fs_minfree
226 	 *     fs_rotdelay
227 	 *     fs_maxcontig
228 	 *     fs_maxbpg
229 	 *     fs_minfree,
230 	 *     fs_optim
231 	 *     fs_flags
232 	 *
233 	 * We probably should rather change the summary for the cylinder group
234 	 * statistics here to the value of what would be in there, if the file
235 	 * system were created initially with the new size. Therefor we still
236 	 * need to find an easy way of calculating that.
237 	 * Possibly we can try to read the first superblock copy and apply the
238 	 * "diffed" stats between the old and new superblock by still copying
239 	 * certain parameters onto that.
240 	 */
241 	sblock.fs_time = modtime;
242 	sblock.fs_fmod = 0;
243 	sblock.fs_clean = 1;
244 	sblock.fs_ronly = 0;
245 	sblock.fs_cgrotor = 0;
246 	sblock.fs_state = 0;
247 	memset((void *)&sblock.fs_fsmnt, 0, sizeof(sblock.fs_fsmnt));
248 
249 	/*
250 	 * Now write the new superblock, its summary information,
251 	 * and all the alternates back to disk.
252 	 */
253 	if (!Nflag && sbput(fso, &sblock, sblock.fs_ncg) != 0)
254 		errc(3, EIO, "could not write updated superblock");
255 	DBG_PRINT0("fscs written\n");
256 
257 #ifdef FS_DEBUG
258 	{
259 		struct csum	*dbg_csp;
260 		u_int32_t	dbg_csc;
261 		char	dbg_line[80];
262 
263 		dbg_csp = fscs;
264 		for (dbg_csc = 0; dbg_csc < sblock.fs_ncg; dbg_csc++) {
265 			snprintf(dbg_line, sizeof(dbg_line),
266 			    "%d. new csum in new location", dbg_csc);
267 			DBG_DUMP_CSUM(&sblock, dbg_line, dbg_csp++);
268 		}
269 	}
270 #endif /* FS_DEBUG */
271 
272 	DBG_PRINT0("sblock written\n");
273 	DBG_DUMP_FS(&sblock, "new initial sblock");
274 
275 	DBG_PRINT0("sblock copies written\n");
276 	DBG_DUMP_FS(&sblock, "new other sblocks");
277 
278 	DBG_LEAVE;
279 	return;
280 }
281 
282 /*
283  * This creates a new cylinder group structure, for more details please see
284  * the source of newfs(8), as this function is taken over almost unchanged.
285  * As this is never called for the first cylinder group, the special
286  * provisions for that case are removed here.
287  */
288 static void
289 initcg(int cylno, time_t modtime, int fso, unsigned int Nflag)
290 {
291 	DBG_FUNC("initcg")
292 	static caddr_t iobuf;
293 	static long iobufsize;
294 	long blkno, start;
295 	ino_t ino;
296 	ufs2_daddr_t i, cbase, dmax;
297 	struct ufs1_dinode *dp1;
298 	struct ufs2_dinode *dp2;
299 	struct csum *cs;
300 	uint j, d, dupper, dlower;
301 
302 	if (iobuf == NULL) {
303 		iobufsize = 2 * sblock.fs_bsize;
304 		if ((iobuf = malloc(iobufsize)) == NULL)
305 			errx(37, "panic: cannot allocate I/O buffer");
306 		memset(iobuf, '\0', iobufsize);
307 	}
308 	/*
309 	 * Determine block bounds for cylinder group.
310 	 * Allow space for super block summary information in first
311 	 * cylinder group.
312 	 */
313 	cbase = cgbase(&sblock, cylno);
314 	dmax = cbase + sblock.fs_fpg;
315 	if (dmax > sblock.fs_size)
316 		dmax = sblock.fs_size;
317 	dlower = cgsblock(&sblock, cylno) - cbase;
318 	dupper = cgdmin(&sblock, cylno) - cbase;
319 	if (cylno == 0)	/* XXX fscs may be relocated */
320 		dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
321 	cs = &fscs[cylno];
322 	memset(&acg, 0, sblock.fs_cgsize);
323 	acg.cg_time = modtime;
324 	acg.cg_magic = CG_MAGIC;
325 	acg.cg_cgx = cylno;
326 	acg.cg_niblk = sblock.fs_ipg;
327 	acg.cg_initediblk = MIN(sblock.fs_ipg, 2 * INOPB(&sblock));
328 	acg.cg_ndblk = dmax - cbase;
329 	if (sblock.fs_contigsumsize > 0)
330 		acg.cg_nclusterblks = acg.cg_ndblk / sblock.fs_frag;
331 	start = sizeof(acg);
332 	if (sblock.fs_magic == FS_UFS2_MAGIC) {
333 		acg.cg_iusedoff = start;
334 	} else {
335 		acg.cg_old_ncyl = sblock.fs_old_cpg;
336 		acg.cg_old_time = acg.cg_time;
337 		acg.cg_time = 0;
338 		acg.cg_old_niblk = acg.cg_niblk;
339 		acg.cg_niblk = 0;
340 		acg.cg_initediblk = 0;
341 		acg.cg_old_btotoff = start;
342 		acg.cg_old_boff = acg.cg_old_btotoff +
343 		    sblock.fs_old_cpg * sizeof(int32_t);
344 		acg.cg_iusedoff = acg.cg_old_boff +
345 		    sblock.fs_old_cpg * sizeof(u_int16_t);
346 	}
347 	acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
348 	acg.cg_nextfreeoff = acg.cg_freeoff + howmany(sblock.fs_fpg, CHAR_BIT);
349 	if (sblock.fs_contigsumsize > 0) {
350 		acg.cg_clustersumoff =
351 		    roundup(acg.cg_nextfreeoff, sizeof(u_int32_t));
352 		acg.cg_clustersumoff -= sizeof(u_int32_t);
353 		acg.cg_clusteroff = acg.cg_clustersumoff +
354 		    (sblock.fs_contigsumsize + 1) * sizeof(u_int32_t);
355 		acg.cg_nextfreeoff = acg.cg_clusteroff +
356 		    howmany(fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
357 	}
358 	if (acg.cg_nextfreeoff > (unsigned)sblock.fs_cgsize) {
359 		/*
360 		 * This should never happen as we would have had that panic
361 		 * already on file system creation
362 		 */
363 		errx(37, "panic: cylinder group too big");
364 	}
365 	acg.cg_cs.cs_nifree += sblock.fs_ipg;
366 	if (cylno == 0)
367 		for (ino = 0; ino < UFS_ROOTINO; ino++) {
368 			setbit(cg_inosused(&acg), ino);
369 			acg.cg_cs.cs_nifree--;
370 		}
371 	/*
372 	 * Initialize the initial inode blocks.
373 	 */
374 	dp1 = (struct ufs1_dinode *)(void *)iobuf;
375 	dp2 = (struct ufs2_dinode *)(void *)iobuf;
376 	for (i = 0; i < acg.cg_initediblk; i++) {
377 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
378 			dp1->di_gen = arc4random();
379 			dp1++;
380 		} else {
381 			dp2->di_gen = arc4random();
382 			dp2++;
383 		}
384 	}
385 	wtfs(fsbtodb(&sblock, cgimin(&sblock, cylno)), iobufsize, iobuf,
386 	    fso, Nflag);
387 	/*
388 	 * For the old file system, we have to initialize all the inodes.
389 	 */
390 	if (sblock.fs_magic == FS_UFS1_MAGIC &&
391 	    sblock.fs_ipg > 2 * INOPB(&sblock)) {
392 		for (i = 2 * sblock.fs_frag;
393 		     i < sblock.fs_ipg / INOPF(&sblock);
394 		     i += sblock.fs_frag) {
395 			dp1 = (struct ufs1_dinode *)(void *)iobuf;
396 			for (j = 0; j < INOPB(&sblock); j++) {
397 				dp1->di_gen = arc4random();
398 				dp1++;
399 			}
400 			wtfs(fsbtodb(&sblock, cgimin(&sblock, cylno) + i),
401 			    sblock.fs_bsize, iobuf, fso, Nflag);
402 		}
403 	}
404 	if (cylno > 0) {
405 		/*
406 		 * In cylno 0, beginning space is reserved
407 		 * for boot and super blocks.
408 		 */
409 		for (d = 0; d < dlower; d += sblock.fs_frag) {
410 			blkno = d / sblock.fs_frag;
411 			setblock(&sblock, cg_blksfree(&acg), blkno);
412 			if (sblock.fs_contigsumsize > 0)
413 				setbit(cg_clustersfree(&acg), blkno);
414 			acg.cg_cs.cs_nbfree++;
415 		}
416 		sblock.fs_dsize += dlower;
417 	}
418 	sblock.fs_dsize += acg.cg_ndblk - dupper;
419 	sblock.fs_old_dsize = sblock.fs_dsize;
420 	if ((i = dupper % sblock.fs_frag)) {
421 		acg.cg_frsum[sblock.fs_frag - i]++;
422 		for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
423 			setbit(cg_blksfree(&acg), dupper);
424 			acg.cg_cs.cs_nffree++;
425 		}
426 	}
427 	for (d = dupper; d + sblock.fs_frag <= acg.cg_ndblk;
428 	    d += sblock.fs_frag) {
429 		blkno = d / sblock.fs_frag;
430 		setblock(&sblock, cg_blksfree(&acg), blkno);
431 		if (sblock.fs_contigsumsize > 0)
432 			setbit(cg_clustersfree(&acg), blkno);
433 		acg.cg_cs.cs_nbfree++;
434 	}
435 	if (d < acg.cg_ndblk) {
436 		acg.cg_frsum[acg.cg_ndblk - d]++;
437 		for (; d < acg.cg_ndblk; d++) {
438 			setbit(cg_blksfree(&acg), d);
439 			acg.cg_cs.cs_nffree++;
440 		}
441 	}
442 	if (sblock.fs_contigsumsize > 0) {
443 		int32_t *sump = cg_clustersum(&acg);
444 		u_char *mapp = cg_clustersfree(&acg);
445 		int map = *mapp++;
446 		int bit = 1;
447 		int run = 0;
448 
449 		for (i = 0; i < acg.cg_nclusterblks; i++) {
450 			if ((map & bit) != 0)
451 				run++;
452 			else if (run != 0) {
453 				if (run > sblock.fs_contigsumsize)
454 					run = sblock.fs_contigsumsize;
455 				sump[run]++;
456 				run = 0;
457 			}
458 			if ((i & (CHAR_BIT - 1)) != CHAR_BIT - 1)
459 				bit <<= 1;
460 			else {
461 				map = *mapp++;
462 				bit = 1;
463 			}
464 		}
465 		if (run != 0) {
466 			if (run > sblock.fs_contigsumsize)
467 				run = sblock.fs_contigsumsize;
468 			sump[run]++;
469 		}
470 	}
471 	sblock.fs_cstotal.cs_ndir += acg.cg_cs.cs_ndir;
472 	sblock.fs_cstotal.cs_nffree += acg.cg_cs.cs_nffree;
473 	sblock.fs_cstotal.cs_nbfree += acg.cg_cs.cs_nbfree;
474 	sblock.fs_cstotal.cs_nifree += acg.cg_cs.cs_nifree;
475 	*cs = acg.cg_cs;
476 
477 	cgckhash(&acg);
478 	wtfs(fsbtodb(&sblock, cgtod(&sblock, cylno)), sblock.fs_cgsize, &acg,
479 	    fso, Nflag);
480 	DBG_DUMP_CG(&sblock, "new cg", &acg);
481 
482 	DBG_LEAVE;
483 	return;
484 }
485 
486 /*
487  * Here we add or subtract (sign +1/-1) the available fragments in a given
488  * block to or from the fragment statistics. By subtracting before and adding
489  * after an operation on the free frag map we can easy update the fragment
490  * statistic, which seems to be otherwise a rather complex operation.
491  */
492 static void
493 frag_adjust(ufs2_daddr_t frag, int sign)
494 {
495 	DBG_FUNC("frag_adjust")
496 	int fragsize;
497 	int f;
498 
499 	DBG_ENTER;
500 
501 	fragsize = 0;
502 	/*
503 	 * Here frag only needs to point to any fragment in the block we want
504 	 * to examine.
505 	 */
506 	for (f = rounddown(frag, sblock.fs_frag);
507 	    f < roundup(frag + 1, sblock.fs_frag); f++) {
508 		/*
509 		 * Count contiguous free fragments.
510 		 */
511 		if (isset(cg_blksfree(&acg), f)) {
512 			fragsize++;
513 		} else {
514 			if (fragsize && fragsize < sblock.fs_frag) {
515 				/*
516 				 * We found something in between.
517 				 */
518 				acg.cg_frsum[fragsize] += sign;
519 				DBG_PRINT2("frag_adjust [%d]+=%d\n",
520 				    fragsize, sign);
521 			}
522 			fragsize = 0;
523 		}
524 	}
525 	if (fragsize && fragsize < sblock.fs_frag) {
526 		/*
527 		 * We found something.
528 		 */
529 		acg.cg_frsum[fragsize] += sign;
530 		DBG_PRINT2("frag_adjust [%d]+=%d\n", fragsize, sign);
531 	}
532 	DBG_PRINT2("frag_adjust [[%d]]+=%d\n", fragsize, sign);
533 
534 	DBG_LEAVE;
535 	return;
536 }
537 
538 /*
539  * Here we do all needed work for the former last cylinder group. It has to be
540  * changed in any case, even if the file system ended exactly on the end of
541  * this group, as there is some slightly inconsistent handling of the number
542  * of cylinders in the cylinder group. We start again by reading the cylinder
543  * group from disk. If the last block was not fully available, we first handle
544  * the missing fragments, then we handle all new full blocks in that file
545  * system and finally we handle the new last fragmented block in the file
546  * system.  We again have to handle the fragment statistics rotational layout
547  * tables and cluster summary during all those operations.
548  */
549 static void
550 updjcg(int cylno, time_t modtime, int fsi, int fso, unsigned int Nflag)
551 {
552 	DBG_FUNC("updjcg")
553 	ufs2_daddr_t cbase, dmax;
554 	struct csum *cs;
555 	int i, k;
556 	int j = 0;
557 
558 	DBG_ENTER;
559 
560 	/*
561 	 * Read the former last (joining) cylinder group from disk, and make
562 	 * a copy.
563 	 */
564 	rdfs(fsbtodb(&osblock, cgtod(&osblock, cylno)),
565 	    (size_t)osblock.fs_cgsize, (void *)&aocg, fsi);
566 	DBG_PRINT0("jcg read\n");
567 	DBG_DUMP_CG(&sblock, "old joining cg", &aocg);
568 
569 	memcpy((void *)&cgun1, (void *)&cgun2, sizeof(cgun2));
570 
571 	/*
572 	 * If the cylinder group had already its new final size almost
573 	 * nothing is to be done ... except:
574 	 * For some reason the value of cg_ncyl in the last cylinder group has
575 	 * to be zero instead of fs_cpg. As this is now no longer the last
576 	 * cylinder group we have to change that value now to fs_cpg.
577 	 */
578 
579 	if (cgbase(&osblock, cylno + 1) == osblock.fs_size) {
580 		if (sblock.fs_magic == FS_UFS1_MAGIC)
581 			acg.cg_old_ncyl = sblock.fs_old_cpg;
582 
583 		cgckhash(&acg);
584 		wtfs(fsbtodb(&sblock, cgtod(&sblock, cylno)),
585 		    (size_t)sblock.fs_cgsize, (void *)&acg, fso, Nflag);
586 		DBG_PRINT0("jcg written\n");
587 		DBG_DUMP_CG(&sblock, "new joining cg", &acg);
588 
589 		DBG_LEAVE;
590 		return;
591 	}
592 
593 	/*
594 	 * Set up some variables needed later.
595 	 */
596 	cbase = cgbase(&sblock, cylno);
597 	dmax = cbase + sblock.fs_fpg;
598 	if (dmax > sblock.fs_size)
599 		dmax = sblock.fs_size;
600 
601 	/*
602 	 * Set pointer to the cylinder summary for our cylinder group.
603 	 */
604 	cs = fscs + cylno;
605 
606 	/*
607 	 * Touch the cylinder group, update all fields in the cylinder group as
608 	 * needed, update the free space in the superblock.
609 	 */
610 	acg.cg_time = modtime;
611 	if ((unsigned)cylno == sblock.fs_ncg - 1) {
612 		/*
613 		 * This is still the last cylinder group.
614 		 */
615 		if (sblock.fs_magic == FS_UFS1_MAGIC)
616 			acg.cg_old_ncyl =
617 			    sblock.fs_old_ncyl % sblock.fs_old_cpg;
618 	} else {
619 		acg.cg_old_ncyl = sblock.fs_old_cpg;
620 	}
621 	DBG_PRINT2("jcg dbg: %d %u", cylno, sblock.fs_ncg);
622 #ifdef FS_DEBUG
623 	if (sblock.fs_magic == FS_UFS1_MAGIC)
624 		DBG_PRINT2("%d %u", acg.cg_old_ncyl, sblock.fs_old_cpg);
625 #endif
626 	DBG_PRINT0("\n");
627 	acg.cg_ndblk = dmax - cbase;
628 	sblock.fs_dsize += acg.cg_ndblk - aocg.cg_ndblk;
629 	sblock.fs_old_dsize = sblock.fs_dsize;
630 	if (sblock.fs_contigsumsize > 0)
631 		acg.cg_nclusterblks = acg.cg_ndblk / sblock.fs_frag;
632 
633 	/*
634 	 * Now we have to update the free fragment bitmap for our new free
635 	 * space.  There again we have to handle the fragmentation and also
636 	 * the rotational layout tables and the cluster summary.  This is
637 	 * also done per fragment for the first new block if the old file
638 	 * system end was not on a block boundary, per fragment for the new
639 	 * last block if the new file system end is not on a block boundary,
640 	 * and per block for all space in between.
641 	 *
642 	 * Handle the first new block here if it was partially available
643 	 * before.
644 	 */
645 	if (osblock.fs_size % sblock.fs_frag) {
646 		if (roundup(osblock.fs_size, sblock.fs_frag) <=
647 		    sblock.fs_size) {
648 			/*
649 			 * The new space is enough to fill at least this
650 			 * block
651 			 */
652 			j = 0;
653 			for (i = roundup(osblock.fs_size - cbase,
654 			    sblock.fs_frag) - 1; i >= osblock.fs_size - cbase;
655 			    i--) {
656 				setbit(cg_blksfree(&acg), i);
657 				acg.cg_cs.cs_nffree++;
658 				j++;
659 			}
660 
661 			/*
662 			 * Check if the fragment just created could join an
663 			 * already existing fragment at the former end of the
664 			 * file system.
665 			 */
666 			if (isblock(&sblock, cg_blksfree(&acg),
667 			    ((osblock.fs_size - cgbase(&sblock, cylno)) /
668 			     sblock.fs_frag))) {
669 				/*
670 				 * The block is now completely available.
671 				 */
672 				DBG_PRINT0("block was\n");
673 				acg.cg_frsum[osblock.fs_size % sblock.fs_frag]--;
674 				acg.cg_cs.cs_nbfree++;
675 				acg.cg_cs.cs_nffree -= sblock.fs_frag;
676 				k = rounddown(osblock.fs_size - cbase,
677 				    sblock.fs_frag);
678 				updclst((osblock.fs_size - cbase) /
679 				    sblock.fs_frag);
680 			} else {
681 				/*
682 				 * Lets rejoin a possible partially growed
683 				 * fragment.
684 				 */
685 				k = 0;
686 				while (isset(cg_blksfree(&acg), i) &&
687 				    (i >= rounddown(osblock.fs_size - cbase,
688 				    sblock.fs_frag))) {
689 					i--;
690 					k++;
691 				}
692 				if (k)
693 					acg.cg_frsum[k]--;
694 				acg.cg_frsum[k + j]++;
695 			}
696 		} else {
697 			/*
698 			 * We only grow by some fragments within this last
699 			 * block.
700 			 */
701 			for (i = sblock.fs_size - cbase - 1;
702 			    i >= osblock.fs_size - cbase; i--) {
703 				setbit(cg_blksfree(&acg), i);
704 				acg.cg_cs.cs_nffree++;
705 				j++;
706 			}
707 			/*
708 			 * Lets rejoin a possible partially growed fragment.
709 			 */
710 			k = 0;
711 			while (isset(cg_blksfree(&acg), i) &&
712 			    (i >= rounddown(osblock.fs_size - cbase,
713 			    sblock.fs_frag))) {
714 				i--;
715 				k++;
716 			}
717 			if (k)
718 				acg.cg_frsum[k]--;
719 			acg.cg_frsum[k + j]++;
720 		}
721 	}
722 
723 	/*
724 	 * Handle all new complete blocks here.
725 	 */
726 	for (i = roundup(osblock.fs_size - cbase, sblock.fs_frag);
727 	    i + sblock.fs_frag <= dmax - cbase;	/* XXX <= or only < ? */
728 	    i += sblock.fs_frag) {
729 		j = i / sblock.fs_frag;
730 		setblock(&sblock, cg_blksfree(&acg), j);
731 		updclst(j);
732 		acg.cg_cs.cs_nbfree++;
733 	}
734 
735 	/*
736 	 * Handle the last new block if there are stll some new fragments left.
737 	 * Here we don't have to bother about the cluster summary or the even
738 	 * the rotational layout table.
739 	 */
740 	if (i < (dmax - cbase)) {
741 		acg.cg_frsum[dmax - cbase - i]++;
742 		for (; i < dmax - cbase; i++) {
743 			setbit(cg_blksfree(&acg), i);
744 			acg.cg_cs.cs_nffree++;
745 		}
746 	}
747 
748 	sblock.fs_cstotal.cs_nffree +=
749 	    (acg.cg_cs.cs_nffree - aocg.cg_cs.cs_nffree);
750 	sblock.fs_cstotal.cs_nbfree +=
751 	    (acg.cg_cs.cs_nbfree - aocg.cg_cs.cs_nbfree);
752 	/*
753 	 * The following statistics are not changed here:
754 	 *     sblock.fs_cstotal.cs_ndir
755 	 *     sblock.fs_cstotal.cs_nifree
756 	 * As the statistics for this cylinder group are ready, copy it to
757 	 * the summary information array.
758 	 */
759 	*cs = acg.cg_cs;
760 
761 	/*
762 	 * Write the updated "joining" cylinder group back to disk.
763 	 */
764 	cgckhash(&acg);
765 	wtfs(fsbtodb(&sblock, cgtod(&sblock, cylno)), (size_t)sblock.fs_cgsize,
766 	    (void *)&acg, fso, Nflag);
767 	DBG_PRINT0("jcg written\n");
768 	DBG_DUMP_CG(&sblock, "new joining cg", &acg);
769 
770 	DBG_LEAVE;
771 	return;
772 }
773 
774 /*
775  * Here we update the location of the cylinder summary. We have two possible
776  * ways of growing the cylinder summary:
777  * (1)	We can try to grow the summary in the current location, and relocate
778  *	possibly used blocks within the current cylinder group.
779  * (2)	Alternatively we can relocate the whole cylinder summary to the first
780  *	new completely empty cylinder group. Once the cylinder summary is no
781  *	longer in the beginning of the first cylinder group you should never
782  *	use a version of fsck which is not aware of the possibility to have
783  *	this structure in a non standard place.
784  * Option (2) is considered to be less intrusive to the structure of the file-
785  * system, so that's the one being used.
786  */
787 static void
788 updcsloc(time_t modtime, int fsi, int fso, unsigned int Nflag)
789 {
790 	DBG_FUNC("updcsloc")
791 	struct csum *cs;
792 	int ocscg, ncscg;
793 	ufs2_daddr_t d;
794 	int lcs = 0;
795 	int block;
796 
797 	DBG_ENTER;
798 
799 	if (howmany(sblock.fs_cssize, sblock.fs_fsize) ==
800 	    howmany(osblock.fs_cssize, osblock.fs_fsize)) {
801 		/*
802 		 * No new fragment needed.
803 		 */
804 		DBG_LEAVE;
805 		return;
806 	}
807 	/* Adjust fs_dsize by added summary blocks */
808 	sblock.fs_dsize -= howmany(sblock.fs_cssize, sblock.fs_fsize) -
809 	    howmany(osblock.fs_cssize, osblock.fs_fsize);
810 	sblock.fs_old_dsize = sblock.fs_dsize;
811 	ocscg = dtog(&osblock, osblock.fs_csaddr);
812 	cs = fscs + ocscg;
813 
814 	/*
815 	 * Read original cylinder group from disk, and make a copy.
816 	 * XXX	If Nflag is set in some very rare cases we now miss
817 	 *	some changes done in updjcg by reading the unmodified
818 	 *	block from disk.
819 	 */
820 	rdfs(fsbtodb(&osblock, cgtod(&osblock, ocscg)),
821 	    (size_t)osblock.fs_cgsize, (void *)&aocg, fsi);
822 	DBG_PRINT0("oscg read\n");
823 	DBG_DUMP_CG(&sblock, "old summary cg", &aocg);
824 
825 	memcpy((void *)&cgun1, (void *)&cgun2, sizeof(cgun2));
826 
827 	/*
828 	 * Touch the cylinder group, set up local variables needed later
829 	 * and update the superblock.
830 	 */
831 	acg.cg_time = modtime;
832 
833 	/*
834 	 * XXX	In the case of having active snapshots we may need much more
835 	 *	blocks for the copy on write. We need each block twice, and
836 	 *	also up to 8*3 blocks for indirect blocks for all possible
837 	 *	references.
838 	 */
839 	/*
840 	 * There is not enough space in the old cylinder group to
841 	 * relocate all blocks as needed, so we relocate the whole
842 	 * cylinder group summary to a new group. We try to use the
843 	 * first complete new cylinder group just created. Within the
844 	 * cylinder group we align the area immediately after the
845 	 * cylinder group information location in order to be as
846 	 * close as possible to the original implementation of ffs.
847 	 *
848 	 * First we have to make sure we'll find enough space in the
849 	 * new cylinder group. If not, then we currently give up.
850 	 * We start with freeing everything which was used by the
851 	 * fragments of the old cylinder summary in the current group.
852 	 * Now we write back the group meta data, read in the needed
853 	 * meta data from the new cylinder group, and start allocating
854 	 * within that group. Here we can assume, the group to be
855 	 * completely empty. Which makes the handling of fragments and
856 	 * clusters a lot easier.
857 	 */
858 	DBG_TRC;
859 	if (sblock.fs_ncg - osblock.fs_ncg < 2)
860 		errx(2, "panic: not enough space");
861 
862 	/*
863 	 * Point "d" to the first fragment not used by the cylinder
864 	 * summary.
865 	 */
866 	d = osblock.fs_csaddr + (osblock.fs_cssize / osblock.fs_fsize);
867 
868 	/*
869 	 * Set up last cluster size ("lcs") already here. Calculate
870 	 * the size for the trailing cluster just behind where "d"
871 	 * points to.
872 	 */
873 	if (sblock.fs_contigsumsize > 0) {
874 		for (block = howmany(d % sblock.fs_fpg, sblock.fs_frag),
875 		    lcs = 0; lcs < sblock.fs_contigsumsize; block++, lcs++) {
876 			if (isclr(cg_clustersfree(&acg), block))
877 				break;
878 		}
879 	}
880 
881 	/*
882 	 * Point "d" to the last frag used by the cylinder summary.
883 	 */
884 	d--;
885 
886 	DBG_PRINT1("d=%jd\n", (intmax_t)d);
887 	if ((d + 1) % sblock.fs_frag) {
888 		/*
889 		 * The end of the cylinder summary is not a complete
890 		 * block.
891 		 */
892 		DBG_TRC;
893 		frag_adjust(d % sblock.fs_fpg, -1);
894 		for (; (d + 1) % sblock.fs_frag; d--) {
895 			DBG_PRINT1("d=%jd\n", (intmax_t)d);
896 			setbit(cg_blksfree(&acg), d % sblock.fs_fpg);
897 			acg.cg_cs.cs_nffree++;
898 			sblock.fs_cstotal.cs_nffree++;
899 		}
900 		/*
901 		 * Point "d" to the last fragment of the last
902 		 * (incomplete) block of the cylinder summary.
903 		 */
904 		d++;
905 		frag_adjust(d % sblock.fs_fpg, 1);
906 
907 		if (isblock(&sblock, cg_blksfree(&acg),
908 		    (d % sblock.fs_fpg) / sblock.fs_frag)) {
909 			DBG_PRINT1("d=%jd\n", (intmax_t)d);
910 			acg.cg_cs.cs_nffree -= sblock.fs_frag;
911 			acg.cg_cs.cs_nbfree++;
912 			sblock.fs_cstotal.cs_nffree -= sblock.fs_frag;
913 			sblock.fs_cstotal.cs_nbfree++;
914 			if (sblock.fs_contigsumsize > 0) {
915 				setbit(cg_clustersfree(&acg),
916 				    (d % sblock.fs_fpg) / sblock.fs_frag);
917 				if (lcs < sblock.fs_contigsumsize) {
918 					if (lcs)
919 						cg_clustersum(&acg)[lcs]--;
920 					lcs++;
921 					cg_clustersum(&acg)[lcs]++;
922 				}
923 			}
924 		}
925 		/*
926 		 * Point "d" to the first fragment of the block before
927 		 * the last incomplete block.
928 		 */
929 		d--;
930 	}
931 
932 	DBG_PRINT1("d=%jd\n", (intmax_t)d);
933 	for (d = rounddown(d, sblock.fs_frag); d >= osblock.fs_csaddr;
934 	    d -= sblock.fs_frag) {
935 		DBG_TRC;
936 		DBG_PRINT1("d=%jd\n", (intmax_t)d);
937 		setblock(&sblock, cg_blksfree(&acg),
938 		    (d % sblock.fs_fpg) / sblock.fs_frag);
939 		acg.cg_cs.cs_nbfree++;
940 		sblock.fs_cstotal.cs_nbfree++;
941 		if (sblock.fs_contigsumsize > 0) {
942 			setbit(cg_clustersfree(&acg),
943 			    (d % sblock.fs_fpg) / sblock.fs_frag);
944 			/*
945 			 * The last cluster size is already set up.
946 			 */
947 			if (lcs < sblock.fs_contigsumsize) {
948 				if (lcs)
949 					cg_clustersum(&acg)[lcs]--;
950 				lcs++;
951 				cg_clustersum(&acg)[lcs]++;
952 			}
953 		}
954 	}
955 	*cs = acg.cg_cs;
956 
957 	/*
958 	 * Now write the former cylinder group containing the cylinder
959 	 * summary back to disk.
960 	 */
961 	cgckhash(&acg);
962 	wtfs(fsbtodb(&sblock, cgtod(&sblock, ocscg)),
963 	    (size_t)sblock.fs_cgsize, (void *)&acg, fso, Nflag);
964 	DBG_PRINT0("oscg written\n");
965 	DBG_DUMP_CG(&sblock, "old summary cg", &acg);
966 
967 	/*
968 	 * Find the beginning of the new cylinder group containing the
969 	 * cylinder summary.
970 	 */
971 	sblock.fs_csaddr = cgdmin(&sblock, osblock.fs_ncg);
972 	ncscg = dtog(&sblock, sblock.fs_csaddr);
973 	cs = fscs + ncscg;
974 
975 	/*
976 	 * If Nflag is specified, we would now read random data instead
977 	 * of an empty cg structure from disk. So we can't simulate that
978 	 * part for now.
979 	 */
980 	if (Nflag) {
981 		DBG_PRINT0("nscg update skipped\n");
982 		DBG_LEAVE;
983 		return;
984 	}
985 
986 	/*
987 	 * Read the future cylinder group containing the cylinder
988 	 * summary from disk, and make a copy.
989 	 */
990 	rdfs(fsbtodb(&sblock, cgtod(&sblock, ncscg)),
991 	    (size_t)sblock.fs_cgsize, (void *)&aocg, fsi);
992 	DBG_PRINT0("nscg read\n");
993 	DBG_DUMP_CG(&sblock, "new summary cg", &aocg);
994 
995 	memcpy((void *)&cgun1, (void *)&cgun2, sizeof(cgun2));
996 
997 	/*
998 	 * Allocate all complete blocks used by the new cylinder
999 	 * summary.
1000 	 */
1001 	for (d = sblock.fs_csaddr; d + sblock.fs_frag <=
1002 	    sblock.fs_csaddr + (sblock.fs_cssize / sblock.fs_fsize);
1003 	    d += sblock.fs_frag) {
1004 		clrblock(&sblock, cg_blksfree(&acg),
1005 		    (d % sblock.fs_fpg) / sblock.fs_frag);
1006 		acg.cg_cs.cs_nbfree--;
1007 		sblock.fs_cstotal.cs_nbfree--;
1008 		if (sblock.fs_contigsumsize > 0) {
1009 			clrbit(cg_clustersfree(&acg),
1010 			    (d % sblock.fs_fpg) / sblock.fs_frag);
1011 		}
1012 	}
1013 
1014 	/*
1015 	 * Allocate all fragments used by the cylinder summary in the
1016 	 * last block.
1017 	 */
1018 	if (d < sblock.fs_csaddr + (sblock.fs_cssize / sblock.fs_fsize)) {
1019 		for (; d - sblock.fs_csaddr <
1020 		    sblock.fs_cssize/sblock.fs_fsize; d++) {
1021 			clrbit(cg_blksfree(&acg), d % sblock.fs_fpg);
1022 			acg.cg_cs.cs_nffree--;
1023 			sblock.fs_cstotal.cs_nffree--;
1024 		}
1025 		acg.cg_cs.cs_nbfree--;
1026 		acg.cg_cs.cs_nffree += sblock.fs_frag;
1027 		sblock.fs_cstotal.cs_nbfree--;
1028 		sblock.fs_cstotal.cs_nffree += sblock.fs_frag;
1029 		if (sblock.fs_contigsumsize > 0)
1030 			clrbit(cg_clustersfree(&acg),
1031 			    (d % sblock.fs_fpg) / sblock.fs_frag);
1032 
1033 		frag_adjust(d % sblock.fs_fpg, 1);
1034 	}
1035 	/*
1036 	 * XXX	Handle the cluster statistics here in the case this
1037 	 *	cylinder group is now almost full, and the remaining
1038 	 *	space is less then the maximum cluster size. This is
1039 	 *	probably not needed, as you would hardly find a file
1040 	 *	system which has only MAXCSBUFS+FS_MAXCONTIG of free
1041 	 *	space right behind the cylinder group information in
1042 	 *	any new cylinder group.
1043 	 */
1044 
1045 	/*
1046 	 * Update our statistics in the cylinder summary.
1047 	 */
1048 	*cs = acg.cg_cs;
1049 
1050 	/*
1051 	 * Write the new cylinder group containing the cylinder summary
1052 	 * back to disk.
1053 	 */
1054 	cgckhash(&acg);
1055 	wtfs(fsbtodb(&sblock, cgtod(&sblock, ncscg)),
1056 	    (size_t)sblock.fs_cgsize, (void *)&acg, fso, Nflag);
1057 	DBG_PRINT0("nscg written\n");
1058 	DBG_DUMP_CG(&sblock, "new summary cg", &acg);
1059 
1060 	DBG_LEAVE;
1061 	return;
1062 }
1063 
1064 /*
1065  * Here we read some block(s) from disk.
1066  */
1067 static void
1068 rdfs(ufs2_daddr_t bno, size_t size, void *bf, int fsi)
1069 {
1070 	DBG_FUNC("rdfs")
1071 	ssize_t	n;
1072 
1073 	DBG_ENTER;
1074 
1075 	if (bno < 0)
1076 		err(32, "rdfs: attempting to read negative block number");
1077 	if (lseek(fsi, (off_t)bno * DEV_BSIZE, 0) < 0)
1078 		err(33, "rdfs: seek error: %jd", (intmax_t)bno);
1079 	n = read(fsi, bf, size);
1080 	if (n != (ssize_t)size)
1081 		err(34, "rdfs: read error: %jd", (intmax_t)bno);
1082 
1083 	DBG_LEAVE;
1084 	return;
1085 }
1086 
1087 /*
1088  * Here we write some block(s) to disk.
1089  */
1090 static void
1091 wtfs(ufs2_daddr_t bno, size_t size, void *bf, int fso, unsigned int Nflag)
1092 {
1093 	DBG_FUNC("wtfs")
1094 	ssize_t	n;
1095 
1096 	DBG_ENTER;
1097 
1098 	if (Nflag) {
1099 		DBG_LEAVE;
1100 		return;
1101 	}
1102 	if (lseek(fso, (off_t)bno * DEV_BSIZE, SEEK_SET) < 0)
1103 		err(35, "wtfs: seek error: %ld", (long)bno);
1104 	n = write(fso, bf, size);
1105 	if (n != (ssize_t)size)
1106 		err(36, "wtfs: write error: %ld", (long)bno);
1107 
1108 	DBG_LEAVE;
1109 	return;
1110 }
1111 
1112 /*
1113  * Here we check if all frags of a block are free. For more details again
1114  * please see the source of newfs(8), as this function is taken over almost
1115  * unchanged.
1116  */
1117 static int
1118 isblock(struct fs *fs, unsigned char *cp, int h)
1119 {
1120 	DBG_FUNC("isblock")
1121 	unsigned char mask;
1122 
1123 	DBG_ENTER;
1124 
1125 	switch (fs->fs_frag) {
1126 	case 8:
1127 		DBG_LEAVE;
1128 		return (cp[h] == 0xff);
1129 	case 4:
1130 		mask = 0x0f << ((h & 0x1) << 2);
1131 		DBG_LEAVE;
1132 		return ((cp[h >> 1] & mask) == mask);
1133 	case 2:
1134 		mask = 0x03 << ((h & 0x3) << 1);
1135 		DBG_LEAVE;
1136 		return ((cp[h >> 2] & mask) == mask);
1137 	case 1:
1138 		mask = 0x01 << (h & 0x7);
1139 		DBG_LEAVE;
1140 		return ((cp[h >> 3] & mask) == mask);
1141 	default:
1142 		fprintf(stderr, "isblock bad fs_frag %d\n", fs->fs_frag);
1143 		DBG_LEAVE;
1144 		return (0);
1145 	}
1146 }
1147 
1148 /*
1149  * Here we allocate a complete block in the block map. For more details again
1150  * please see the source of newfs(8), as this function is taken over almost
1151  * unchanged.
1152  */
1153 static void
1154 clrblock(struct fs *fs, unsigned char *cp, int h)
1155 {
1156 	DBG_FUNC("clrblock")
1157 
1158 	DBG_ENTER;
1159 
1160 	switch ((fs)->fs_frag) {
1161 	case 8:
1162 		cp[h] = 0;
1163 		break;
1164 	case 4:
1165 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
1166 		break;
1167 	case 2:
1168 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
1169 		break;
1170 	case 1:
1171 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
1172 		break;
1173 	default:
1174 		warnx("clrblock bad fs_frag %d", fs->fs_frag);
1175 		break;
1176 	}
1177 
1178 	DBG_LEAVE;
1179 	return;
1180 }
1181 
1182 /*
1183  * Here we free a complete block in the free block map. For more details again
1184  * please see the source of newfs(8), as this function is taken over almost
1185  * unchanged.
1186  */
1187 static void
1188 setblock(struct fs *fs, unsigned char *cp, int h)
1189 {
1190 	DBG_FUNC("setblock")
1191 
1192 	DBG_ENTER;
1193 
1194 	switch (fs->fs_frag) {
1195 	case 8:
1196 		cp[h] = 0xff;
1197 		break;
1198 	case 4:
1199 		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
1200 		break;
1201 	case 2:
1202 		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
1203 		break;
1204 	case 1:
1205 		cp[h >> 3] |= (0x01 << (h & 0x7));
1206 		break;
1207 	default:
1208 		warnx("setblock bad fs_frag %d", fs->fs_frag);
1209 		break;
1210 	}
1211 
1212 	DBG_LEAVE;
1213 	return;
1214 }
1215 
1216 /*
1217  * Figure out how many lines our current terminal has. For more details again
1218  * please see the source of newfs(8), as this function is taken over almost
1219  * unchanged.
1220  */
1221 static int
1222 charsperline(void)
1223 {
1224 	DBG_FUNC("charsperline")
1225 	int columns;
1226 	char *cp;
1227 	struct winsize ws;
1228 
1229 	DBG_ENTER;
1230 
1231 	columns = 0;
1232 	if (ioctl(0, TIOCGWINSZ, &ws) != -1)
1233 		columns = ws.ws_col;
1234 	if (columns == 0 && (cp = getenv("COLUMNS")))
1235 		columns = atoi(cp);
1236 	if (columns == 0)
1237 		columns = 80;	/* last resort */
1238 
1239 	DBG_LEAVE;
1240 	return (columns);
1241 }
1242 
1243 static int
1244 is_dev(const char *name)
1245 {
1246 	struct stat devstat;
1247 
1248 	if (stat(name, &devstat) != 0)
1249 		return (0);
1250 	if (!S_ISCHR(devstat.st_mode))
1251 		return (0);
1252 	return (1);
1253 }
1254 
1255 static const char *
1256 getdev(const char *name, struct statfs *statfsp)
1257 {
1258 	static char device[MAXPATHLEN];
1259 	const char *cp;
1260 
1261 	if (is_dev(name))
1262 		return (name);
1263 
1264 	cp = strrchr(name, '/');
1265 	if (cp == NULL) {
1266 		snprintf(device, sizeof(device), "%s%s", _PATH_DEV, name);
1267 		if (is_dev(device))
1268 			return (device);
1269 	}
1270 
1271 	if (statfsp != NULL)
1272 		return (statfsp->f_mntfromname);
1273 
1274 	return (NULL);
1275 }
1276 
1277 /*
1278  * growfs(8) is a utility which allows to increase the size of an existing
1279  * ufs file system. Currently this can only be done on unmounted file system.
1280  * It recognizes some command line options to specify the new desired size,
1281  * and it does some basic checkings. The old file system size is determined
1282  * and after some more checks like we can really access the new last block
1283  * on the disk etc. we calculate the new parameters for the superblock. After
1284  * having done this we just call growfs() which will do the work.
1285  * We still have to provide support for snapshots. Therefore we first have to
1286  * understand what data structures are always replicated in the snapshot on
1287  * creation, for all other blocks we touch during our procedure, we have to
1288  * keep the old blocks unchanged somewhere available for the snapshots. If we
1289  * are lucky, then we only have to handle our blocks to be relocated in that
1290  * way.
1291  * Also we have to consider in what order we actually update the critical
1292  * data structures of the file system to make sure, that in case of a disaster
1293  * fsck(8) is still able to restore any lost data.
1294  * The foreseen last step then will be to provide for growing even mounted
1295  * file systems. There we have to extend the mount() system call to provide
1296  * userland access to the file system locking facility.
1297  */
1298 int
1299 main(int argc, char **argv)
1300 {
1301 	DBG_FUNC("main")
1302 	struct fs *fs;
1303 	const char *device;
1304 	struct statfs *statfsp;
1305 	uint64_t size = 0;
1306 	off_t mediasize;
1307 	int error, j, fsi, fso, ch, ret, Nflag = 0, yflag = 0;
1308 	char *p, reply[5], oldsizebuf[6], newsizebuf[6];
1309 	void *testbuf;
1310 
1311 	DBG_ENTER;
1312 
1313 	while ((ch = getopt(argc, argv, "Ns:vy")) != -1) {
1314 		switch(ch) {
1315 		case 'N':
1316 			Nflag = 1;
1317 			break;
1318 		case 's':
1319 			size = (off_t)strtoumax(optarg, &p, 0);
1320 			if (p == NULL || *p == '\0')
1321 				size *= DEV_BSIZE;
1322 			else if (*p == 'b' || *p == 'B')
1323 				; /* do nothing */
1324 			else if (*p == 'k' || *p == 'K')
1325 				size <<= 10;
1326 			else if (*p == 'm' || *p == 'M')
1327 				size <<= 20;
1328 			else if (*p == 'g' || *p == 'G')
1329 				size <<= 30;
1330 			else if (*p == 't' || *p == 'T') {
1331 				size <<= 30;
1332 				size <<= 10;
1333 			} else
1334 				errx(2, "unknown suffix on -s argument");
1335 			break;
1336 		case 'v': /* for compatibility to newfs */
1337 			break;
1338 		case 'y':
1339 			yflag = 1;
1340 			break;
1341 		case '?':
1342 			/* FALLTHROUGH */
1343 		default:
1344 			usage();
1345 		}
1346 	}
1347 	argc -= optind;
1348 	argv += optind;
1349 
1350 	if (argc != 1)
1351 		usage();
1352 
1353 	/*
1354 	 * Now try to guess the device name.
1355 	 */
1356 	statfsp = getmntpoint(*argv);
1357 	device = getdev(*argv, statfsp);
1358 	if (device == NULL)
1359 		errx(2, "cannot find special device for %s", *argv);
1360 
1361 	fsi = open(device, O_RDONLY);
1362 	if (fsi < 0)
1363 		err(3, "%s", device);
1364 
1365 	/*
1366 	 * Try to guess the slice size if not specified.
1367 	 */
1368 	if (ioctl(fsi, DIOCGMEDIASIZE, &mediasize) == -1)
1369 		err(3,"DIOCGMEDIASIZE");
1370 
1371 	/*
1372 	 * Check if that partition is suitable for growing a file system.
1373 	 */
1374 	if (mediasize < 1)
1375 		errx(2, "partition is unavailable");
1376 
1377 	/*
1378 	 * Read the current superblock, and take a backup.
1379 	 */
1380 	if ((ret = sbget(fsi, &fs, UFS_STDSB, 0)) != 0) {
1381 		switch (ret) {
1382 		case ENOENT:
1383 			errx(2, "superblock not recognized");
1384 		default:
1385 			errc(3, ret, "unable to read superblock");
1386 		}
1387 	}
1388 	/*
1389 	 * Check for filesystem that was unclean at mount time.
1390 	 */
1391 	if ((fs->fs_flags & (FS_UNCLEAN | FS_NEEDSFSCK)) != 0)
1392 		errx(2, "%s is not clean - run fsck.\n", *argv);
1393 	memcpy(&osblock, fs, fs->fs_sbsize);
1394 	free(fs);
1395 	memcpy((void *)&fsun1, (void *)&fsun2, osblock.fs_sbsize);
1396 
1397 	DBG_OPEN("/tmp/growfs.debug"); /* already here we need a superblock */
1398 	DBG_DUMP_FS(&sblock, "old sblock");
1399 
1400 	/*
1401 	 * Determine size to grow to. Default to the device size.
1402 	 */
1403 	if (size == 0)
1404 		size = mediasize;
1405 	else {
1406 		if (size > (uint64_t)mediasize) {
1407 			humanize_number(oldsizebuf, sizeof(oldsizebuf), size,
1408 			    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1409 			humanize_number(newsizebuf, sizeof(newsizebuf),
1410 			    mediasize,
1411 			    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1412 
1413 			errx(2, "requested size %s is larger "
1414 			    "than the available %s", oldsizebuf, newsizebuf);
1415 		}
1416 	}
1417 
1418 	/*
1419 	 * Make sure the new size is a multiple of fs_fsize; /dev/ufssuspend
1420 	 * only supports fragment-aligned IO requests.
1421 	 */
1422 	size -= size % osblock.fs_fsize;
1423 
1424 	if (size <= (uint64_t)(osblock.fs_size * osblock.fs_fsize)) {
1425 		humanize_number(oldsizebuf, sizeof(oldsizebuf),
1426 		    osblock.fs_size * osblock.fs_fsize,
1427 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1428 		humanize_number(newsizebuf, sizeof(newsizebuf), size,
1429 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1430 
1431 		if (size == (uint64_t)(osblock.fs_size * osblock.fs_fsize))
1432 			errx(0, "requested size %s is equal to the current "
1433 			    "filesystem size %s", newsizebuf, oldsizebuf);
1434 		errx(2, "requested size %s is smaller than the current "
1435 		   "filesystem size %s", newsizebuf, oldsizebuf);
1436 	}
1437 
1438 	sblock.fs_old_size = sblock.fs_size =
1439 	    dbtofsb(&osblock, size / DEV_BSIZE);
1440 	sblock.fs_providersize = dbtofsb(&osblock, mediasize / DEV_BSIZE);
1441 
1442 	/*
1443 	 * Are we really growing?
1444 	 */
1445 	if (osblock.fs_size >= sblock.fs_size) {
1446 		errx(3, "we are not growing (%jd->%jd)",
1447 		    (intmax_t)osblock.fs_size, (intmax_t)sblock.fs_size);
1448 	}
1449 
1450 	/*
1451 	 * Check if we find an active snapshot.
1452 	 */
1453 	if (yflag == 0) {
1454 		for (j = 0; j < FSMAXSNAP; j++) {
1455 			if (sblock.fs_snapinum[j]) {
1456 				errx(2, "active snapshot found in file system; "
1457 				    "please remove all snapshots before "
1458 				    "using growfs");
1459 			}
1460 			if (!sblock.fs_snapinum[j]) /* list is dense */
1461 				break;
1462 		}
1463 	}
1464 
1465 	if (yflag == 0 && Nflag == 0) {
1466 		if (statfsp != NULL && (statfsp->f_flags & MNT_RDONLY) == 0)
1467 			printf("Device is mounted read-write; resizing will "
1468 			    "result in temporary write suspension for %s.\n",
1469 			    statfsp->f_mntonname);
1470 		printf("It's strongly recommended to make a backup "
1471 		    "before growing the file system.\n"
1472 		    "OK to grow filesystem on %s", device);
1473 		if (statfsp != NULL)
1474 			printf(", mounted on %s,", statfsp->f_mntonname);
1475 		humanize_number(oldsizebuf, sizeof(oldsizebuf),
1476 		    osblock.fs_size * osblock.fs_fsize,
1477 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1478 		humanize_number(newsizebuf, sizeof(newsizebuf),
1479 		    sblock.fs_size * sblock.fs_fsize,
1480 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1481 		printf(" from %s to %s? [yes/no] ", oldsizebuf, newsizebuf);
1482 		fflush(stdout);
1483 		fgets(reply, (int)sizeof(reply), stdin);
1484 		if (strcasecmp(reply, "yes\n")){
1485 			printf("Response other than \"yes\"; aborting\n");
1486 			exit(0);
1487 		}
1488 	}
1489 
1490 	/*
1491 	 * Try to access our device for writing.  If it's not mounted,
1492 	 * or mounted read-only, simply open it; otherwise, use UFS
1493 	 * suspension mechanism.
1494 	 */
1495 	if (Nflag) {
1496 		fso = -1;
1497 	} else {
1498 		if (statfsp != NULL && (statfsp->f_flags & MNT_RDONLY) == 0) {
1499 			fso = open(_PATH_UFSSUSPEND, O_RDWR);
1500 			if (fso == -1)
1501 				err(3, "unable to open %s", _PATH_UFSSUSPEND);
1502 			error = ioctl(fso, UFSSUSPEND, &statfsp->f_fsid);
1503 			if (error != 0)
1504 				err(3, "UFSSUSPEND");
1505 		} else {
1506 			fso = open(device, O_WRONLY);
1507 			if (fso < 0)
1508 				err(3, "%s", device);
1509 		}
1510 	}
1511 
1512 	/*
1513 	 * Try to access our new last block in the file system.
1514 	 */
1515 	testbuf = malloc(sblock.fs_fsize);
1516 	if (testbuf == NULL)
1517 		err(3, "malloc");
1518 	rdfs((ufs2_daddr_t)((size - sblock.fs_fsize) / DEV_BSIZE),
1519 	    sblock.fs_fsize, testbuf, fsi);
1520 	wtfs((ufs2_daddr_t)((size - sblock.fs_fsize) / DEV_BSIZE),
1521 	    sblock.fs_fsize, testbuf, fso, Nflag);
1522 	free(testbuf);
1523 
1524 	/*
1525 	 * Now calculate new superblock values and check for reasonable
1526 	 * bound for new file system size:
1527 	 *     fs_size:    is derived from user input
1528 	 *     fs_dsize:   should get updated in the routines creating or
1529 	 *                 updating the cylinder groups on the fly
1530 	 *     fs_cstotal: should get updated in the routines creating or
1531 	 *                 updating the cylinder groups
1532 	 */
1533 
1534 	/*
1535 	 * Update the number of cylinders and cylinder groups in the file system.
1536 	 */
1537 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
1538 		sblock.fs_old_ncyl =
1539 		    sblock.fs_size * sblock.fs_old_nspf / sblock.fs_old_spc;
1540 		if (sblock.fs_size * sblock.fs_old_nspf >
1541 		    sblock.fs_old_ncyl * sblock.fs_old_spc)
1542 			sblock.fs_old_ncyl++;
1543 	}
1544 	sblock.fs_ncg = howmany(sblock.fs_size, sblock.fs_fpg);
1545 
1546 	/*
1547 	 * Allocate last cylinder group only if there is enough room
1548 	 * for at least one data block.
1549 	 */
1550 	if (sblock.fs_size % sblock.fs_fpg != 0 &&
1551 	    sblock.fs_size <= cgdmin(&sblock, sblock.fs_ncg - 1)) {
1552 		humanize_number(oldsizebuf, sizeof(oldsizebuf),
1553 		    (sblock.fs_size % sblock.fs_fpg) * sblock.fs_fsize,
1554 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1555 		warnx("no room to allocate last cylinder group; "
1556 		    "leaving %s unused", oldsizebuf);
1557 		sblock.fs_ncg--;
1558 		if (sblock.fs_magic == FS_UFS1_MAGIC)
1559 			sblock.fs_old_ncyl = sblock.fs_ncg * sblock.fs_old_cpg;
1560 		sblock.fs_old_size = sblock.fs_size =
1561 		    sblock.fs_ncg * sblock.fs_fpg;
1562 	}
1563 
1564 	/*
1565 	 * Update the space for the cylinder group summary information in the
1566 	 * respective cylinder group data area.
1567 	 */
1568 	sblock.fs_cssize =
1569 	    fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));
1570 
1571 	if (osblock.fs_size >= sblock.fs_size)
1572 		errx(3, "not enough new space");
1573 
1574 	DBG_PRINT0("sblock calculated\n");
1575 
1576 	/*
1577 	 * Ok, everything prepared, so now let's do the tricks.
1578 	 */
1579 	growfs(fsi, fso, Nflag);
1580 
1581 	close(fsi);
1582 	if (fso > -1) {
1583 		if (statfsp != NULL && (statfsp->f_flags & MNT_RDONLY) == 0) {
1584 			error = ioctl(fso, UFSRESUME);
1585 			if (error != 0)
1586 				err(3, "UFSRESUME");
1587 		}
1588 		error = close(fso);
1589 		if (error != 0)
1590 			err(3, "close");
1591 		if (statfsp != NULL && (statfsp->f_flags & MNT_RDONLY) != 0 &&
1592 		    chkdoreload(statfsp, warn) != 0)
1593 			exit(9);
1594 	}
1595 
1596 	DBG_CLOSE;
1597 
1598 	DBG_LEAVE;
1599 	return (0);
1600 }
1601 
1602 /*
1603  * Dump a line of usage.
1604  */
1605 static void
1606 usage(void)
1607 {
1608 	DBG_FUNC("usage")
1609 
1610 	DBG_ENTER;
1611 
1612 	fprintf(stderr, "usage: growfs [-Ny] [-s size] special | filesystem\n");
1613 
1614 	DBG_LEAVE;
1615 	exit(1);
1616 }
1617 
1618 /*
1619  * This updates most parameters and the bitmap related to cluster. We have to
1620  * assume that sblock, osblock, acg are set up.
1621  */
1622 static void
1623 updclst(int block)
1624 {
1625 	DBG_FUNC("updclst")
1626 	static int lcs = 0;
1627 
1628 	DBG_ENTER;
1629 
1630 	if (sblock.fs_contigsumsize < 1) /* no clustering */
1631 		return;
1632 	/*
1633 	 * update cluster allocation map
1634 	 */
1635 	setbit(cg_clustersfree(&acg), block);
1636 
1637 	/*
1638 	 * update cluster summary table
1639 	 */
1640 	if (!lcs) {
1641 		/*
1642 		 * calculate size for the trailing cluster
1643 		 */
1644 		for (block--; lcs < sblock.fs_contigsumsize; block--, lcs++ ) {
1645 			if (isclr(cg_clustersfree(&acg), block))
1646 				break;
1647 		}
1648 	}
1649 	if (lcs < sblock.fs_contigsumsize) {
1650 		if (lcs)
1651 			cg_clustersum(&acg)[lcs]--;
1652 		lcs++;
1653 		cg_clustersum(&acg)[lcs]++;
1654 	}
1655 
1656 	DBG_LEAVE;
1657 	return;
1658 }
1659 
1660 /*
1661  * Calculate the check-hash of the cylinder group.
1662  */
1663 static void
1664 cgckhash(struct cg *cgp)
1665 {
1666 
1667 	if ((sblock.fs_metackhash & CK_CYLGRP) == 0)
1668 		return;
1669 	cgp->cg_ckhash = 0;
1670 	cgp->cg_ckhash = calculate_crc32c(~0L, (void *)cgp, sblock.fs_cgsize);
1671 }
1672