xref: /freebsd/sbin/growfs/growfs.c (revision 9768746b)
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 #ifndef lint
49 static const char copyright[] =
50 "@(#) Copyright (c) 2000 Christoph Herrmann, Thomas-Henning von Kamptz\n\
51 Copyright (c) 1980, 1989, 1993 The Regents of the University of California.\n\
52 All rights reserved.\n";
53 #endif /* not lint */
54 
55 #include <sys/cdefs.h>
56 __FBSDID("$FreeBSD$");
57 
58 #include <sys/param.h>
59 #include <sys/ioctl.h>
60 #include <sys/stat.h>
61 #include <sys/disk.h>
62 #include <sys/ucred.h>
63 #include <sys/mount.h>
64 
65 #include <stdio.h>
66 #include <paths.h>
67 #include <ctype.h>
68 #include <err.h>
69 #include <errno.h>
70 #include <fcntl.h>
71 #include <fstab.h>
72 #include <inttypes.h>
73 #include <limits.h>
74 #include <mntopts.h>
75 #include <paths.h>
76 #include <stdlib.h>
77 #include <stdint.h>
78 #include <string.h>
79 #include <time.h>
80 #include <unistd.h>
81 #include <ufs/ufs/dinode.h>
82 #include <ufs/ffs/fs.h>
83 #include <libutil.h>
84 #include <libufs.h>
85 
86 #include "debug.h"
87 
88 #ifdef FS_DEBUG
89 int	_dbg_lvl_ = (DL_INFO);	/* DL_TRC */
90 #endif /* FS_DEBUG */
91 
92 static union {
93 	struct fs	fs;
94 	char		pad[SBLOCKSIZE];
95 } fsun1, fsun2;
96 #define	sblock	fsun1.fs	/* the new superblock */
97 #define	osblock	fsun2.fs	/* the old superblock */
98 
99 static union {
100 	struct cg	cg;
101 	char		pad[MAXBSIZE];
102 } cgun1, cgun2;
103 #define	acg	cgun1.cg	/* a cylinder cgroup (new) */
104 #define	aocg	cgun2.cg	/* an old cylinder group */
105 
106 static struct csum	*fscs;	/* cylinder summary */
107 
108 static void	growfs(int, int, unsigned int);
109 static void	rdfs(ufs2_daddr_t, size_t, void *, int);
110 static void	wtfs(ufs2_daddr_t, size_t, void *, int, unsigned int);
111 static int	charsperline(void);
112 static void	usage(void);
113 static int	isblock(struct fs *, unsigned char *, int);
114 static void	clrblock(struct fs *, unsigned char *, int);
115 static void	setblock(struct fs *, unsigned char *, int);
116 static void	initcg(int, time_t, int, unsigned int);
117 static void	updjcg(int, time_t, int, int, unsigned int);
118 static void	updcsloc(time_t, int, int, unsigned int);
119 static void	frag_adjust(ufs2_daddr_t, int);
120 static void	updclst(int);
121 static void	cgckhash(struct cg *);
122 
123 /*
124  * Here we actually start growing the file system. We basically read the
125  * cylinder summary from the first cylinder group as we want to update
126  * this on the fly during our various operations. First we handle the
127  * changes in the former last cylinder group. Afterwards we create all new
128  * cylinder groups.  Now we handle the cylinder group containing the
129  * cylinder summary which might result in a relocation of the whole
130  * structure.  In the end we write back the updated cylinder summary, the
131  * new superblock, and slightly patched versions of the super block
132  * copies.
133  */
134 static void
135 growfs(int fsi, int fso, unsigned int Nflag)
136 {
137 	DBG_FUNC("growfs")
138 	time_t modtime;
139 	uint cylno;
140 	int i, j, width;
141 	char tmpbuf[100];
142 
143 	DBG_ENTER;
144 
145 	time(&modtime);
146 
147 	/*
148 	 * Get the cylinder summary into the memory.
149 	 */
150 	fscs = (struct csum *)calloc((size_t)1, (size_t)sblock.fs_cssize);
151 	if (fscs == NULL)
152 		errx(1, "calloc failed");
153 	memcpy(fscs, osblock.fs_csp, osblock.fs_cssize);
154 	free(osblock.fs_csp);
155 	osblock.fs_csp = NULL;
156 	sblock.fs_csp = fscs;
157 
158 #ifdef FS_DEBUG
159 	{
160 		struct csum *dbg_csp;
161 		u_int32_t dbg_csc;
162 		char dbg_line[80];
163 
164 		dbg_csp = fscs;
165 
166 		for (dbg_csc = 0; dbg_csc < osblock.fs_ncg; dbg_csc++) {
167 			snprintf(dbg_line, sizeof(dbg_line),
168 			    "%d. old csum in old location", dbg_csc);
169 			DBG_DUMP_CSUM(&osblock, dbg_line, dbg_csp++);
170 		}
171 	}
172 #endif /* FS_DEBUG */
173 	DBG_PRINT0("fscs read\n");
174 
175 	/*
176 	 * Do all needed changes in the former last cylinder group.
177 	 */
178 	updjcg(osblock.fs_ncg - 1, modtime, fsi, fso, Nflag);
179 
180 	/*
181 	 * Dump out summary information about file system.
182 	 */
183 #ifdef FS_DEBUG
184 #define B2MBFACTOR (1 / (1024.0 * 1024.0))
185 	printf("growfs: %.1fMB (%jd sectors) block size %d, fragment size %d\n",
186 	    (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
187 	    (intmax_t)fsbtodb(&sblock, sblock.fs_size), sblock.fs_bsize,
188 	    sblock.fs_fsize);
189 	printf("\tusing %d cylinder groups of %.2fMB, %d blks, %d inodes.\n",
190 	    sblock.fs_ncg, (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
191 	    sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
192 	if (sblock.fs_flags & FS_DOSOFTDEP)
193 		printf("\twith soft updates\n");
194 #undef B2MBFACTOR
195 #endif /* FS_DEBUG */
196 
197 	/*
198 	 * Now build the cylinders group blocks and
199 	 * then print out indices of cylinder groups.
200 	 */
201 	printf("super-block backups (for fsck_ffs -b #) at:\n");
202 	i = 0;
203 	width = charsperline();
204 
205 	/*
206 	 * Iterate for only the new cylinder groups.
207 	 */
208 	for (cylno = osblock.fs_ncg; cylno < sblock.fs_ncg; cylno++) {
209 		initcg(cylno, modtime, fso, Nflag);
210 		j = sprintf(tmpbuf, " %jd%s",
211 		    (intmax_t)fsbtodb(&sblock, cgsblock(&sblock, cylno)),
212 		    cylno < (sblock.fs_ncg - 1) ? "," : "" );
213 		if (i + j >= width) {
214 			printf("\n");
215 			i = 0;
216 		}
217 		i += j;
218 		printf("%s", tmpbuf);
219 		fflush(stdout);
220 	}
221 	printf("\n");
222 
223 	/*
224 	 * Do all needed changes in the first cylinder group.
225 	 * allocate blocks in new location
226 	 */
227 	updcsloc(modtime, fsi, fso, Nflag);
228 
229 	/*
230 	 * Clean up the dynamic fields in our superblock.
231 	 *
232 	 * XXX
233 	 * The following fields are currently distributed from the superblock
234 	 * to the copies:
235 	 *     fs_minfree
236 	 *     fs_rotdelay
237 	 *     fs_maxcontig
238 	 *     fs_maxbpg
239 	 *     fs_minfree,
240 	 *     fs_optim
241 	 *     fs_flags
242 	 *
243 	 * We probably should rather change the summary for the cylinder group
244 	 * statistics here to the value of what would be in there, if the file
245 	 * system were created initially with the new size. Therefor we still
246 	 * need to find an easy way of calculating that.
247 	 * Possibly we can try to read the first superblock copy and apply the
248 	 * "diffed" stats between the old and new superblock by still copying
249 	 * certain parameters onto that.
250 	 */
251 	sblock.fs_time = modtime;
252 	sblock.fs_fmod = 0;
253 	sblock.fs_clean = 1;
254 	sblock.fs_ronly = 0;
255 	sblock.fs_cgrotor = 0;
256 	sblock.fs_state = 0;
257 	memset((void *)&sblock.fs_fsmnt, 0, sizeof(sblock.fs_fsmnt));
258 
259 	/*
260 	 * Now write the new superblock, its summary information,
261 	 * and all the alternates back to disk.
262 	 */
263 	if (!Nflag && sbput(fso, &sblock, sblock.fs_ncg) != 0)
264 		errc(2, EIO, "could not write updated superblock");
265 	DBG_PRINT0("fscs written\n");
266 
267 #ifdef FS_DEBUG
268 	{
269 		struct csum	*dbg_csp;
270 		u_int32_t	dbg_csc;
271 		char	dbg_line[80];
272 
273 		dbg_csp = fscs;
274 		for (dbg_csc = 0; dbg_csc < sblock.fs_ncg; dbg_csc++) {
275 			snprintf(dbg_line, sizeof(dbg_line),
276 			    "%d. new csum in new location", dbg_csc);
277 			DBG_DUMP_CSUM(&sblock, dbg_line, dbg_csp++);
278 		}
279 	}
280 #endif /* FS_DEBUG */
281 
282 	DBG_PRINT0("sblock written\n");
283 	DBG_DUMP_FS(&sblock, "new initial sblock");
284 
285 	DBG_PRINT0("sblock copies written\n");
286 	DBG_DUMP_FS(&sblock, "new other sblocks");
287 
288 	DBG_LEAVE;
289 	return;
290 }
291 
292 /*
293  * This creates a new cylinder group structure, for more details please see
294  * the source of newfs(8), as this function is taken over almost unchanged.
295  * As this is never called for the first cylinder group, the special
296  * provisions for that case are removed here.
297  */
298 static void
299 initcg(int cylno, time_t modtime, int fso, unsigned int Nflag)
300 {
301 	DBG_FUNC("initcg")
302 	static caddr_t iobuf;
303 	static long iobufsize;
304 	long blkno, start;
305 	ino_t ino;
306 	ufs2_daddr_t i, cbase, dmax;
307 	struct ufs1_dinode *dp1;
308 	struct ufs2_dinode *dp2;
309 	struct csum *cs;
310 	uint j, d, dupper, dlower;
311 
312 	if (iobuf == NULL) {
313 		iobufsize = 2 * sblock.fs_bsize;
314 		if ((iobuf = malloc(iobufsize)) == NULL)
315 			errx(37, "panic: cannot allocate I/O buffer");
316 		memset(iobuf, '\0', iobufsize);
317 	}
318 	/*
319 	 * Determine block bounds for cylinder group.
320 	 * Allow space for super block summary information in first
321 	 * cylinder group.
322 	 */
323 	cbase = cgbase(&sblock, cylno);
324 	dmax = cbase + sblock.fs_fpg;
325 	if (dmax > sblock.fs_size)
326 		dmax = sblock.fs_size;
327 	dlower = cgsblock(&sblock, cylno) - cbase;
328 	dupper = cgdmin(&sblock, cylno) - cbase;
329 	if (cylno == 0)	/* XXX fscs may be relocated */
330 		dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
331 	cs = &fscs[cylno];
332 	memset(&acg, 0, sblock.fs_cgsize);
333 	acg.cg_time = modtime;
334 	acg.cg_magic = CG_MAGIC;
335 	acg.cg_cgx = cylno;
336 	acg.cg_niblk = sblock.fs_ipg;
337 	acg.cg_initediblk = MIN(sblock.fs_ipg, 2 * INOPB(&sblock));
338 	acg.cg_ndblk = dmax - cbase;
339 	if (sblock.fs_contigsumsize > 0)
340 		acg.cg_nclusterblks = acg.cg_ndblk / sblock.fs_frag;
341 	start = &acg.cg_space[0] - (u_char *)(&acg.cg_firstfield);
342 	if (sblock.fs_magic == FS_UFS2_MAGIC) {
343 		acg.cg_iusedoff = start;
344 	} else {
345 		acg.cg_old_ncyl = sblock.fs_old_cpg;
346 		acg.cg_old_time = acg.cg_time;
347 		acg.cg_time = 0;
348 		acg.cg_old_niblk = acg.cg_niblk;
349 		acg.cg_niblk = 0;
350 		acg.cg_initediblk = 0;
351 		acg.cg_old_btotoff = start;
352 		acg.cg_old_boff = acg.cg_old_btotoff +
353 		    sblock.fs_old_cpg * sizeof(int32_t);
354 		acg.cg_iusedoff = acg.cg_old_boff +
355 		    sblock.fs_old_cpg * sizeof(u_int16_t);
356 	}
357 	acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
358 	acg.cg_nextfreeoff = acg.cg_freeoff + howmany(sblock.fs_fpg, CHAR_BIT);
359 	if (sblock.fs_contigsumsize > 0) {
360 		acg.cg_clustersumoff =
361 		    roundup(acg.cg_nextfreeoff, sizeof(u_int32_t));
362 		acg.cg_clustersumoff -= sizeof(u_int32_t);
363 		acg.cg_clusteroff = acg.cg_clustersumoff +
364 		    (sblock.fs_contigsumsize + 1) * sizeof(u_int32_t);
365 		acg.cg_nextfreeoff = acg.cg_clusteroff +
366 		    howmany(fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
367 	}
368 	if (acg.cg_nextfreeoff > (unsigned)sblock.fs_cgsize) {
369 		/*
370 		 * This should never happen as we would have had that panic
371 		 * already on file system creation
372 		 */
373 		errx(37, "panic: cylinder group too big");
374 	}
375 	acg.cg_cs.cs_nifree += sblock.fs_ipg;
376 	if (cylno == 0)
377 		for (ino = 0; ino < UFS_ROOTINO; ino++) {
378 			setbit(cg_inosused(&acg), ino);
379 			acg.cg_cs.cs_nifree--;
380 		}
381 	/*
382 	 * Initialize the initial inode blocks.
383 	 */
384 	dp1 = (struct ufs1_dinode *)(void *)iobuf;
385 	dp2 = (struct ufs2_dinode *)(void *)iobuf;
386 	for (i = 0; i < acg.cg_initediblk; i++) {
387 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
388 			dp1->di_gen = arc4random();
389 			dp1++;
390 		} else {
391 			dp2->di_gen = arc4random();
392 			dp2++;
393 		}
394 	}
395 	wtfs(fsbtodb(&sblock, cgimin(&sblock, cylno)), iobufsize, iobuf,
396 	    fso, Nflag);
397 	/*
398 	 * For the old file system, we have to initialize all the inodes.
399 	 */
400 	if (sblock.fs_magic == FS_UFS1_MAGIC &&
401 	    sblock.fs_ipg > 2 * INOPB(&sblock)) {
402 		for (i = 2 * sblock.fs_frag;
403 		     i < sblock.fs_ipg / INOPF(&sblock);
404 		     i += sblock.fs_frag) {
405 			dp1 = (struct ufs1_dinode *)(void *)iobuf;
406 			for (j = 0; j < INOPB(&sblock); j++) {
407 				dp1->di_gen = arc4random();
408 				dp1++;
409 			}
410 			wtfs(fsbtodb(&sblock, cgimin(&sblock, cylno) + i),
411 			    sblock.fs_bsize, iobuf, fso, Nflag);
412 		}
413 	}
414 	if (cylno > 0) {
415 		/*
416 		 * In cylno 0, beginning space is reserved
417 		 * for boot and super blocks.
418 		 */
419 		for (d = 0; d < dlower; d += sblock.fs_frag) {
420 			blkno = d / sblock.fs_frag;
421 			setblock(&sblock, cg_blksfree(&acg), blkno);
422 			if (sblock.fs_contigsumsize > 0)
423 				setbit(cg_clustersfree(&acg), blkno);
424 			acg.cg_cs.cs_nbfree++;
425 		}
426 		sblock.fs_dsize += dlower;
427 	}
428 	sblock.fs_dsize += acg.cg_ndblk - dupper;
429 	sblock.fs_old_dsize = sblock.fs_dsize;
430 	if ((i = dupper % sblock.fs_frag)) {
431 		acg.cg_frsum[sblock.fs_frag - i]++;
432 		for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
433 			setbit(cg_blksfree(&acg), dupper);
434 			acg.cg_cs.cs_nffree++;
435 		}
436 	}
437 	for (d = dupper; d + sblock.fs_frag <= acg.cg_ndblk;
438 	    d += sblock.fs_frag) {
439 		blkno = d / sblock.fs_frag;
440 		setblock(&sblock, cg_blksfree(&acg), blkno);
441 		if (sblock.fs_contigsumsize > 0)
442 			setbit(cg_clustersfree(&acg), blkno);
443 		acg.cg_cs.cs_nbfree++;
444 	}
445 	if (d < acg.cg_ndblk) {
446 		acg.cg_frsum[acg.cg_ndblk - d]++;
447 		for (; d < acg.cg_ndblk; d++) {
448 			setbit(cg_blksfree(&acg), d);
449 			acg.cg_cs.cs_nffree++;
450 		}
451 	}
452 	if (sblock.fs_contigsumsize > 0) {
453 		int32_t *sump = cg_clustersum(&acg);
454 		u_char *mapp = cg_clustersfree(&acg);
455 		int map = *mapp++;
456 		int bit = 1;
457 		int run = 0;
458 
459 		for (i = 0; i < acg.cg_nclusterblks; i++) {
460 			if ((map & bit) != 0)
461 				run++;
462 			else if (run != 0) {
463 				if (run > sblock.fs_contigsumsize)
464 					run = sblock.fs_contigsumsize;
465 				sump[run]++;
466 				run = 0;
467 			}
468 			if ((i & (CHAR_BIT - 1)) != CHAR_BIT - 1)
469 				bit <<= 1;
470 			else {
471 				map = *mapp++;
472 				bit = 1;
473 			}
474 		}
475 		if (run != 0) {
476 			if (run > sblock.fs_contigsumsize)
477 				run = sblock.fs_contigsumsize;
478 			sump[run]++;
479 		}
480 	}
481 	sblock.fs_cstotal.cs_ndir += acg.cg_cs.cs_ndir;
482 	sblock.fs_cstotal.cs_nffree += acg.cg_cs.cs_nffree;
483 	sblock.fs_cstotal.cs_nbfree += acg.cg_cs.cs_nbfree;
484 	sblock.fs_cstotal.cs_nifree += acg.cg_cs.cs_nifree;
485 	*cs = acg.cg_cs;
486 
487 	cgckhash(&acg);
488 	wtfs(fsbtodb(&sblock, cgtod(&sblock, cylno)), sblock.fs_cgsize, &acg,
489 	    fso, Nflag);
490 	DBG_DUMP_CG(&sblock, "new cg", &acg);
491 
492 	DBG_LEAVE;
493 	return;
494 }
495 
496 /*
497  * Here we add or subtract (sign +1/-1) the available fragments in a given
498  * block to or from the fragment statistics. By subtracting before and adding
499  * after an operation on the free frag map we can easy update the fragment
500  * statistic, which seems to be otherwise a rather complex operation.
501  */
502 static void
503 frag_adjust(ufs2_daddr_t frag, int sign)
504 {
505 	DBG_FUNC("frag_adjust")
506 	int fragsize;
507 	int f;
508 
509 	DBG_ENTER;
510 
511 	fragsize = 0;
512 	/*
513 	 * Here frag only needs to point to any fragment in the block we want
514 	 * to examine.
515 	 */
516 	for (f = rounddown(frag, sblock.fs_frag);
517 	    f < roundup(frag + 1, sblock.fs_frag); f++) {
518 		/*
519 		 * Count contiguous free fragments.
520 		 */
521 		if (isset(cg_blksfree(&acg), f)) {
522 			fragsize++;
523 		} else {
524 			if (fragsize && fragsize < sblock.fs_frag) {
525 				/*
526 				 * We found something in between.
527 				 */
528 				acg.cg_frsum[fragsize] += sign;
529 				DBG_PRINT2("frag_adjust [%d]+=%d\n",
530 				    fragsize, sign);
531 			}
532 			fragsize = 0;
533 		}
534 	}
535 	if (fragsize && fragsize < sblock.fs_frag) {
536 		/*
537 		 * We found something.
538 		 */
539 		acg.cg_frsum[fragsize] += sign;
540 		DBG_PRINT2("frag_adjust [%d]+=%d\n", fragsize, sign);
541 	}
542 	DBG_PRINT2("frag_adjust [[%d]]+=%d\n", fragsize, sign);
543 
544 	DBG_LEAVE;
545 	return;
546 }
547 
548 /*
549  * Here we do all needed work for the former last cylinder group. It has to be
550  * changed in any case, even if the file system ended exactly on the end of
551  * this group, as there is some slightly inconsistent handling of the number
552  * of cylinders in the cylinder group. We start again by reading the cylinder
553  * group from disk. If the last block was not fully available, we first handle
554  * the missing fragments, then we handle all new full blocks in that file
555  * system and finally we handle the new last fragmented block in the file
556  * system.  We again have to handle the fragment statistics rotational layout
557  * tables and cluster summary during all those operations.
558  */
559 static void
560 updjcg(int cylno, time_t modtime, int fsi, int fso, unsigned int Nflag)
561 {
562 	DBG_FUNC("updjcg")
563 	ufs2_daddr_t cbase, dmax;
564 	struct csum *cs;
565 	int i, k;
566 	int j = 0;
567 
568 	DBG_ENTER;
569 
570 	/*
571 	 * Read the former last (joining) cylinder group from disk, and make
572 	 * a copy.
573 	 */
574 	rdfs(fsbtodb(&osblock, cgtod(&osblock, cylno)),
575 	    (size_t)osblock.fs_cgsize, (void *)&aocg, fsi);
576 	DBG_PRINT0("jcg read\n");
577 	DBG_DUMP_CG(&sblock, "old joining cg", &aocg);
578 
579 	memcpy((void *)&cgun1, (void *)&cgun2, sizeof(cgun2));
580 
581 	/*
582 	 * If the cylinder group had already its new final size almost
583 	 * nothing is to be done ... except:
584 	 * For some reason the value of cg_ncyl in the last cylinder group has
585 	 * to be zero instead of fs_cpg. As this is now no longer the last
586 	 * cylinder group we have to change that value now to fs_cpg.
587 	 */
588 
589 	if (cgbase(&osblock, cylno + 1) == osblock.fs_size) {
590 		if (sblock.fs_magic == FS_UFS1_MAGIC)
591 			acg.cg_old_ncyl = sblock.fs_old_cpg;
592 
593 		cgckhash(&acg);
594 		wtfs(fsbtodb(&sblock, cgtod(&sblock, cylno)),
595 		    (size_t)sblock.fs_cgsize, (void *)&acg, fso, Nflag);
596 		DBG_PRINT0("jcg written\n");
597 		DBG_DUMP_CG(&sblock, "new joining cg", &acg);
598 
599 		DBG_LEAVE;
600 		return;
601 	}
602 
603 	/*
604 	 * Set up some variables needed later.
605 	 */
606 	cbase = cgbase(&sblock, cylno);
607 	dmax = cbase + sblock.fs_fpg;
608 	if (dmax > sblock.fs_size)
609 		dmax = sblock.fs_size;
610 
611 	/*
612 	 * Set pointer to the cylinder summary for our cylinder group.
613 	 */
614 	cs = fscs + cylno;
615 
616 	/*
617 	 * Touch the cylinder group, update all fields in the cylinder group as
618 	 * needed, update the free space in the superblock.
619 	 */
620 	acg.cg_time = modtime;
621 	if ((unsigned)cylno == sblock.fs_ncg - 1) {
622 		/*
623 		 * This is still the last cylinder group.
624 		 */
625 		if (sblock.fs_magic == FS_UFS1_MAGIC)
626 			acg.cg_old_ncyl =
627 			    sblock.fs_old_ncyl % sblock.fs_old_cpg;
628 	} else {
629 		acg.cg_old_ncyl = sblock.fs_old_cpg;
630 	}
631 	DBG_PRINT2("jcg dbg: %d %u", cylno, sblock.fs_ncg);
632 #ifdef FS_DEBUG
633 	if (sblock.fs_magic == FS_UFS1_MAGIC)
634 		DBG_PRINT2("%d %u", acg.cg_old_ncyl, sblock.fs_old_cpg);
635 #endif
636 	DBG_PRINT0("\n");
637 	acg.cg_ndblk = dmax - cbase;
638 	sblock.fs_dsize += acg.cg_ndblk - aocg.cg_ndblk;
639 	sblock.fs_old_dsize = sblock.fs_dsize;
640 	if (sblock.fs_contigsumsize > 0)
641 		acg.cg_nclusterblks = acg.cg_ndblk / sblock.fs_frag;
642 
643 	/*
644 	 * Now we have to update the free fragment bitmap for our new free
645 	 * space.  There again we have to handle the fragmentation and also
646 	 * the rotational layout tables and the cluster summary.  This is
647 	 * also done per fragment for the first new block if the old file
648 	 * system end was not on a block boundary, per fragment for the new
649 	 * last block if the new file system end is not on a block boundary,
650 	 * and per block for all space in between.
651 	 *
652 	 * Handle the first new block here if it was partially available
653 	 * before.
654 	 */
655 	if (osblock.fs_size % sblock.fs_frag) {
656 		if (roundup(osblock.fs_size, sblock.fs_frag) <=
657 		    sblock.fs_size) {
658 			/*
659 			 * The new space is enough to fill at least this
660 			 * block
661 			 */
662 			j = 0;
663 			for (i = roundup(osblock.fs_size - cbase,
664 			    sblock.fs_frag) - 1; i >= osblock.fs_size - cbase;
665 			    i--) {
666 				setbit(cg_blksfree(&acg), i);
667 				acg.cg_cs.cs_nffree++;
668 				j++;
669 			}
670 
671 			/*
672 			 * Check if the fragment just created could join an
673 			 * already existing fragment at the former end of the
674 			 * file system.
675 			 */
676 			if (isblock(&sblock, cg_blksfree(&acg),
677 			    ((osblock.fs_size - cgbase(&sblock, cylno)) /
678 			     sblock.fs_frag))) {
679 				/*
680 				 * The block is now completely available.
681 				 */
682 				DBG_PRINT0("block was\n");
683 				acg.cg_frsum[osblock.fs_size % sblock.fs_frag]--;
684 				acg.cg_cs.cs_nbfree++;
685 				acg.cg_cs.cs_nffree -= sblock.fs_frag;
686 				k = rounddown(osblock.fs_size - cbase,
687 				    sblock.fs_frag);
688 				updclst((osblock.fs_size - cbase) /
689 				    sblock.fs_frag);
690 			} else {
691 				/*
692 				 * Lets rejoin a possible partially growed
693 				 * fragment.
694 				 */
695 				k = 0;
696 				while (isset(cg_blksfree(&acg), i) &&
697 				    (i >= rounddown(osblock.fs_size - cbase,
698 				    sblock.fs_frag))) {
699 					i--;
700 					k++;
701 				}
702 				if (k)
703 					acg.cg_frsum[k]--;
704 				acg.cg_frsum[k + j]++;
705 			}
706 		} else {
707 			/*
708 			 * We only grow by some fragments within this last
709 			 * block.
710 			 */
711 			for (i = sblock.fs_size - cbase - 1;
712 			    i >= osblock.fs_size - cbase; i--) {
713 				setbit(cg_blksfree(&acg), i);
714 				acg.cg_cs.cs_nffree++;
715 				j++;
716 			}
717 			/*
718 			 * Lets rejoin a possible partially growed fragment.
719 			 */
720 			k = 0;
721 			while (isset(cg_blksfree(&acg), i) &&
722 			    (i >= rounddown(osblock.fs_size - cbase,
723 			    sblock.fs_frag))) {
724 				i--;
725 				k++;
726 			}
727 			if (k)
728 				acg.cg_frsum[k]--;
729 			acg.cg_frsum[k + j]++;
730 		}
731 	}
732 
733 	/*
734 	 * Handle all new complete blocks here.
735 	 */
736 	for (i = roundup(osblock.fs_size - cbase, sblock.fs_frag);
737 	    i + sblock.fs_frag <= dmax - cbase;	/* XXX <= or only < ? */
738 	    i += sblock.fs_frag) {
739 		j = i / sblock.fs_frag;
740 		setblock(&sblock, cg_blksfree(&acg), j);
741 		updclst(j);
742 		acg.cg_cs.cs_nbfree++;
743 	}
744 
745 	/*
746 	 * Handle the last new block if there are stll some new fragments left.
747 	 * Here we don't have to bother about the cluster summary or the even
748 	 * the rotational layout table.
749 	 */
750 	if (i < (dmax - cbase)) {
751 		acg.cg_frsum[dmax - cbase - i]++;
752 		for (; i < dmax - cbase; i++) {
753 			setbit(cg_blksfree(&acg), i);
754 			acg.cg_cs.cs_nffree++;
755 		}
756 	}
757 
758 	sblock.fs_cstotal.cs_nffree +=
759 	    (acg.cg_cs.cs_nffree - aocg.cg_cs.cs_nffree);
760 	sblock.fs_cstotal.cs_nbfree +=
761 	    (acg.cg_cs.cs_nbfree - aocg.cg_cs.cs_nbfree);
762 	/*
763 	 * The following statistics are not changed here:
764 	 *     sblock.fs_cstotal.cs_ndir
765 	 *     sblock.fs_cstotal.cs_nifree
766 	 * As the statistics for this cylinder group are ready, copy it to
767 	 * the summary information array.
768 	 */
769 	*cs = acg.cg_cs;
770 
771 	/*
772 	 * Write the updated "joining" cylinder group back to disk.
773 	 */
774 	cgckhash(&acg);
775 	wtfs(fsbtodb(&sblock, cgtod(&sblock, cylno)), (size_t)sblock.fs_cgsize,
776 	    (void *)&acg, fso, Nflag);
777 	DBG_PRINT0("jcg written\n");
778 	DBG_DUMP_CG(&sblock, "new joining cg", &acg);
779 
780 	DBG_LEAVE;
781 	return;
782 }
783 
784 /*
785  * Here we update the location of the cylinder summary. We have two possible
786  * ways of growing the cylinder summary:
787  * (1)	We can try to grow the summary in the current location, and relocate
788  *	possibly used blocks within the current cylinder group.
789  * (2)	Alternatively we can relocate the whole cylinder summary to the first
790  *	new completely empty cylinder group. Once the cylinder summary is no
791  *	longer in the beginning of the first cylinder group you should never
792  *	use a version of fsck which is not aware of the possibility to have
793  *	this structure in a non standard place.
794  * Option (2) is considered to be less intrusive to the structure of the file-
795  * system, so that's the one being used.
796  */
797 static void
798 updcsloc(time_t modtime, int fsi, int fso, unsigned int Nflag)
799 {
800 	DBG_FUNC("updcsloc")
801 	struct csum *cs;
802 	int ocscg, ncscg;
803 	ufs2_daddr_t d;
804 	int lcs = 0;
805 	int block;
806 
807 	DBG_ENTER;
808 
809 	if (howmany(sblock.fs_cssize, sblock.fs_fsize) ==
810 	    howmany(osblock.fs_cssize, osblock.fs_fsize)) {
811 		/*
812 		 * No new fragment needed.
813 		 */
814 		DBG_LEAVE;
815 		return;
816 	}
817 	/* Adjust fs_dsize by added summary blocks */
818 	sblock.fs_dsize -= howmany(sblock.fs_cssize, sblock.fs_fsize) -
819 	    howmany(osblock.fs_cssize, osblock.fs_fsize);
820 	sblock.fs_old_dsize = sblock.fs_dsize;
821 	ocscg = dtog(&osblock, osblock.fs_csaddr);
822 	cs = fscs + ocscg;
823 
824 	/*
825 	 * Read original cylinder group from disk, and make a copy.
826 	 * XXX	If Nflag is set in some very rare cases we now miss
827 	 *	some changes done in updjcg by reading the unmodified
828 	 *	block from disk.
829 	 */
830 	rdfs(fsbtodb(&osblock, cgtod(&osblock, ocscg)),
831 	    (size_t)osblock.fs_cgsize, (void *)&aocg, fsi);
832 	DBG_PRINT0("oscg read\n");
833 	DBG_DUMP_CG(&sblock, "old summary cg", &aocg);
834 
835 	memcpy((void *)&cgun1, (void *)&cgun2, sizeof(cgun2));
836 
837 	/*
838 	 * Touch the cylinder group, set up local variables needed later
839 	 * and update the superblock.
840 	 */
841 	acg.cg_time = modtime;
842 
843 	/*
844 	 * XXX	In the case of having active snapshots we may need much more
845 	 *	blocks for the copy on write. We need each block twice, and
846 	 *	also up to 8*3 blocks for indirect blocks for all possible
847 	 *	references.
848 	 */
849 	/*
850 	 * There is not enough space in the old cylinder group to
851 	 * relocate all blocks as needed, so we relocate the whole
852 	 * cylinder group summary to a new group. We try to use the
853 	 * first complete new cylinder group just created. Within the
854 	 * cylinder group we align the area immediately after the
855 	 * cylinder group information location in order to be as
856 	 * close as possible to the original implementation of ffs.
857 	 *
858 	 * First we have to make sure we'll find enough space in the
859 	 * new cylinder group. If not, then we currently give up.
860 	 * We start with freeing everything which was used by the
861 	 * fragments of the old cylinder summary in the current group.
862 	 * Now we write back the group meta data, read in the needed
863 	 * meta data from the new cylinder group, and start allocating
864 	 * within that group. Here we can assume, the group to be
865 	 * completely empty. Which makes the handling of fragments and
866 	 * clusters a lot easier.
867 	 */
868 	DBG_TRC;
869 	if (sblock.fs_ncg - osblock.fs_ncg < 2)
870 		errx(2, "panic: not enough space");
871 
872 	/*
873 	 * Point "d" to the first fragment not used by the cylinder
874 	 * summary.
875 	 */
876 	d = osblock.fs_csaddr + (osblock.fs_cssize / osblock.fs_fsize);
877 
878 	/*
879 	 * Set up last cluster size ("lcs") already here. Calculate
880 	 * the size for the trailing cluster just behind where "d"
881 	 * points to.
882 	 */
883 	if (sblock.fs_contigsumsize > 0) {
884 		for (block = howmany(d % sblock.fs_fpg, sblock.fs_frag),
885 		    lcs = 0; lcs < sblock.fs_contigsumsize; block++, lcs++) {
886 			if (isclr(cg_clustersfree(&acg), block))
887 				break;
888 		}
889 	}
890 
891 	/*
892 	 * Point "d" to the last frag used by the cylinder summary.
893 	 */
894 	d--;
895 
896 	DBG_PRINT1("d=%jd\n", (intmax_t)d);
897 	if ((d + 1) % sblock.fs_frag) {
898 		/*
899 		 * The end of the cylinder summary is not a complete
900 		 * block.
901 		 */
902 		DBG_TRC;
903 		frag_adjust(d % sblock.fs_fpg, -1);
904 		for (; (d + 1) % sblock.fs_frag; d--) {
905 			DBG_PRINT1("d=%jd\n", (intmax_t)d);
906 			setbit(cg_blksfree(&acg), d % sblock.fs_fpg);
907 			acg.cg_cs.cs_nffree++;
908 			sblock.fs_cstotal.cs_nffree++;
909 		}
910 		/*
911 		 * Point "d" to the last fragment of the last
912 		 * (incomplete) block of the cylinder summary.
913 		 */
914 		d++;
915 		frag_adjust(d % sblock.fs_fpg, 1);
916 
917 		if (isblock(&sblock, cg_blksfree(&acg),
918 		    (d % sblock.fs_fpg) / sblock.fs_frag)) {
919 			DBG_PRINT1("d=%jd\n", (intmax_t)d);
920 			acg.cg_cs.cs_nffree -= sblock.fs_frag;
921 			acg.cg_cs.cs_nbfree++;
922 			sblock.fs_cstotal.cs_nffree -= sblock.fs_frag;
923 			sblock.fs_cstotal.cs_nbfree++;
924 			if (sblock.fs_contigsumsize > 0) {
925 				setbit(cg_clustersfree(&acg),
926 				    (d % sblock.fs_fpg) / sblock.fs_frag);
927 				if (lcs < sblock.fs_contigsumsize) {
928 					if (lcs)
929 						cg_clustersum(&acg)[lcs]--;
930 					lcs++;
931 					cg_clustersum(&acg)[lcs]++;
932 				}
933 			}
934 		}
935 		/*
936 		 * Point "d" to the first fragment of the block before
937 		 * the last incomplete block.
938 		 */
939 		d--;
940 	}
941 
942 	DBG_PRINT1("d=%jd\n", (intmax_t)d);
943 	for (d = rounddown(d, sblock.fs_frag); d >= osblock.fs_csaddr;
944 	    d -= sblock.fs_frag) {
945 		DBG_TRC;
946 		DBG_PRINT1("d=%jd\n", (intmax_t)d);
947 		setblock(&sblock, cg_blksfree(&acg),
948 		    (d % sblock.fs_fpg) / sblock.fs_frag);
949 		acg.cg_cs.cs_nbfree++;
950 		sblock.fs_cstotal.cs_nbfree++;
951 		if (sblock.fs_contigsumsize > 0) {
952 			setbit(cg_clustersfree(&acg),
953 			    (d % sblock.fs_fpg) / sblock.fs_frag);
954 			/*
955 			 * The last cluster size is already set up.
956 			 */
957 			if (lcs < sblock.fs_contigsumsize) {
958 				if (lcs)
959 					cg_clustersum(&acg)[lcs]--;
960 				lcs++;
961 				cg_clustersum(&acg)[lcs]++;
962 			}
963 		}
964 	}
965 	*cs = acg.cg_cs;
966 
967 	/*
968 	 * Now write the former cylinder group containing the cylinder
969 	 * summary back to disk.
970 	 */
971 	cgckhash(&acg);
972 	wtfs(fsbtodb(&sblock, cgtod(&sblock, ocscg)),
973 	    (size_t)sblock.fs_cgsize, (void *)&acg, fso, Nflag);
974 	DBG_PRINT0("oscg written\n");
975 	DBG_DUMP_CG(&sblock, "old summary cg", &acg);
976 
977 	/*
978 	 * Find the beginning of the new cylinder group containing the
979 	 * cylinder summary.
980 	 */
981 	sblock.fs_csaddr = cgdmin(&sblock, osblock.fs_ncg);
982 	ncscg = dtog(&sblock, sblock.fs_csaddr);
983 	cs = fscs + ncscg;
984 
985 	/*
986 	 * If Nflag is specified, we would now read random data instead
987 	 * of an empty cg structure from disk. So we can't simulate that
988 	 * part for now.
989 	 */
990 	if (Nflag) {
991 		DBG_PRINT0("nscg update skipped\n");
992 		DBG_LEAVE;
993 		return;
994 	}
995 
996 	/*
997 	 * Read the future cylinder group containing the cylinder
998 	 * summary from disk, and make a copy.
999 	 */
1000 	rdfs(fsbtodb(&sblock, cgtod(&sblock, ncscg)),
1001 	    (size_t)sblock.fs_cgsize, (void *)&aocg, fsi);
1002 	DBG_PRINT0("nscg read\n");
1003 	DBG_DUMP_CG(&sblock, "new summary cg", &aocg);
1004 
1005 	memcpy((void *)&cgun1, (void *)&cgun2, sizeof(cgun2));
1006 
1007 	/*
1008 	 * Allocate all complete blocks used by the new cylinder
1009 	 * summary.
1010 	 */
1011 	for (d = sblock.fs_csaddr; d + sblock.fs_frag <=
1012 	    sblock.fs_csaddr + (sblock.fs_cssize / sblock.fs_fsize);
1013 	    d += sblock.fs_frag) {
1014 		clrblock(&sblock, cg_blksfree(&acg),
1015 		    (d % sblock.fs_fpg) / sblock.fs_frag);
1016 		acg.cg_cs.cs_nbfree--;
1017 		sblock.fs_cstotal.cs_nbfree--;
1018 		if (sblock.fs_contigsumsize > 0) {
1019 			clrbit(cg_clustersfree(&acg),
1020 			    (d % sblock.fs_fpg) / sblock.fs_frag);
1021 		}
1022 	}
1023 
1024 	/*
1025 	 * Allocate all fragments used by the cylinder summary in the
1026 	 * last block.
1027 	 */
1028 	if (d < sblock.fs_csaddr + (sblock.fs_cssize / sblock.fs_fsize)) {
1029 		for (; d - sblock.fs_csaddr <
1030 		    sblock.fs_cssize/sblock.fs_fsize; d++) {
1031 			clrbit(cg_blksfree(&acg), d % sblock.fs_fpg);
1032 			acg.cg_cs.cs_nffree--;
1033 			sblock.fs_cstotal.cs_nffree--;
1034 		}
1035 		acg.cg_cs.cs_nbfree--;
1036 		acg.cg_cs.cs_nffree += sblock.fs_frag;
1037 		sblock.fs_cstotal.cs_nbfree--;
1038 		sblock.fs_cstotal.cs_nffree += sblock.fs_frag;
1039 		if (sblock.fs_contigsumsize > 0)
1040 			clrbit(cg_clustersfree(&acg),
1041 			    (d % sblock.fs_fpg) / sblock.fs_frag);
1042 
1043 		frag_adjust(d % sblock.fs_fpg, 1);
1044 	}
1045 	/*
1046 	 * XXX	Handle the cluster statistics here in the case this
1047 	 *	cylinder group is now almost full, and the remaining
1048 	 *	space is less then the maximum cluster size. This is
1049 	 *	probably not needed, as you would hardly find a file
1050 	 *	system which has only MAXCSBUFS+FS_MAXCONTIG of free
1051 	 *	space right behind the cylinder group information in
1052 	 *	any new cylinder group.
1053 	 */
1054 
1055 	/*
1056 	 * Update our statistics in the cylinder summary.
1057 	 */
1058 	*cs = acg.cg_cs;
1059 
1060 	/*
1061 	 * Write the new cylinder group containing the cylinder summary
1062 	 * back to disk.
1063 	 */
1064 	cgckhash(&acg);
1065 	wtfs(fsbtodb(&sblock, cgtod(&sblock, ncscg)),
1066 	    (size_t)sblock.fs_cgsize, (void *)&acg, fso, Nflag);
1067 	DBG_PRINT0("nscg written\n");
1068 	DBG_DUMP_CG(&sblock, "new summary cg", &acg);
1069 
1070 	DBG_LEAVE;
1071 	return;
1072 }
1073 
1074 /*
1075  * Here we read some block(s) from disk.
1076  */
1077 static void
1078 rdfs(ufs2_daddr_t bno, size_t size, void *bf, int fsi)
1079 {
1080 	DBG_FUNC("rdfs")
1081 	ssize_t	n;
1082 
1083 	DBG_ENTER;
1084 
1085 	if (bno < 0)
1086 		err(32, "rdfs: attempting to read negative block number");
1087 	if (lseek(fsi, (off_t)bno * DEV_BSIZE, 0) < 0)
1088 		err(33, "rdfs: seek error: %jd", (intmax_t)bno);
1089 	n = read(fsi, bf, size);
1090 	if (n != (ssize_t)size)
1091 		err(34, "rdfs: read error: %jd", (intmax_t)bno);
1092 
1093 	DBG_LEAVE;
1094 	return;
1095 }
1096 
1097 /*
1098  * Here we write some block(s) to disk.
1099  */
1100 static void
1101 wtfs(ufs2_daddr_t bno, size_t size, void *bf, int fso, unsigned int Nflag)
1102 {
1103 	DBG_FUNC("wtfs")
1104 	ssize_t	n;
1105 
1106 	DBG_ENTER;
1107 
1108 	if (Nflag) {
1109 		DBG_LEAVE;
1110 		return;
1111 	}
1112 	if (lseek(fso, (off_t)bno * DEV_BSIZE, SEEK_SET) < 0)
1113 		err(35, "wtfs: seek error: %ld", (long)bno);
1114 	n = write(fso, bf, size);
1115 	if (n != (ssize_t)size)
1116 		err(36, "wtfs: write error: %ld", (long)bno);
1117 
1118 	DBG_LEAVE;
1119 	return;
1120 }
1121 
1122 /*
1123  * Here we check if all frags of a block are free. For more details again
1124  * please see the source of newfs(8), as this function is taken over almost
1125  * unchanged.
1126  */
1127 static int
1128 isblock(struct fs *fs, unsigned char *cp, int h)
1129 {
1130 	DBG_FUNC("isblock")
1131 	unsigned char mask;
1132 
1133 	DBG_ENTER;
1134 
1135 	switch (fs->fs_frag) {
1136 	case 8:
1137 		DBG_LEAVE;
1138 		return (cp[h] == 0xff);
1139 	case 4:
1140 		mask = 0x0f << ((h & 0x1) << 2);
1141 		DBG_LEAVE;
1142 		return ((cp[h >> 1] & mask) == mask);
1143 	case 2:
1144 		mask = 0x03 << ((h & 0x3) << 1);
1145 		DBG_LEAVE;
1146 		return ((cp[h >> 2] & mask) == mask);
1147 	case 1:
1148 		mask = 0x01 << (h & 0x7);
1149 		DBG_LEAVE;
1150 		return ((cp[h >> 3] & mask) == mask);
1151 	default:
1152 		fprintf(stderr, "isblock bad fs_frag %d\n", fs->fs_frag);
1153 		DBG_LEAVE;
1154 		return (0);
1155 	}
1156 }
1157 
1158 /*
1159  * Here we allocate a complete block in the block map. For more details again
1160  * please see the source of newfs(8), as this function is taken over almost
1161  * unchanged.
1162  */
1163 static void
1164 clrblock(struct fs *fs, unsigned char *cp, int h)
1165 {
1166 	DBG_FUNC("clrblock")
1167 
1168 	DBG_ENTER;
1169 
1170 	switch ((fs)->fs_frag) {
1171 	case 8:
1172 		cp[h] = 0;
1173 		break;
1174 	case 4:
1175 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
1176 		break;
1177 	case 2:
1178 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
1179 		break;
1180 	case 1:
1181 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
1182 		break;
1183 	default:
1184 		warnx("clrblock bad fs_frag %d", fs->fs_frag);
1185 		break;
1186 	}
1187 
1188 	DBG_LEAVE;
1189 	return;
1190 }
1191 
1192 /*
1193  * Here we free a complete block in the free block map. For more details again
1194  * please see the source of newfs(8), as this function is taken over almost
1195  * unchanged.
1196  */
1197 static void
1198 setblock(struct fs *fs, unsigned char *cp, int h)
1199 {
1200 	DBG_FUNC("setblock")
1201 
1202 	DBG_ENTER;
1203 
1204 	switch (fs->fs_frag) {
1205 	case 8:
1206 		cp[h] = 0xff;
1207 		break;
1208 	case 4:
1209 		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
1210 		break;
1211 	case 2:
1212 		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
1213 		break;
1214 	case 1:
1215 		cp[h >> 3] |= (0x01 << (h & 0x7));
1216 		break;
1217 	default:
1218 		warnx("setblock bad fs_frag %d", fs->fs_frag);
1219 		break;
1220 	}
1221 
1222 	DBG_LEAVE;
1223 	return;
1224 }
1225 
1226 /*
1227  * Figure out how many lines our current terminal has. For more details again
1228  * please see the source of newfs(8), as this function is taken over almost
1229  * unchanged.
1230  */
1231 static int
1232 charsperline(void)
1233 {
1234 	DBG_FUNC("charsperline")
1235 	int columns;
1236 	char *cp;
1237 	struct winsize ws;
1238 
1239 	DBG_ENTER;
1240 
1241 	columns = 0;
1242 	if (ioctl(0, TIOCGWINSZ, &ws) != -1)
1243 		columns = ws.ws_col;
1244 	if (columns == 0 && (cp = getenv("COLUMNS")))
1245 		columns = atoi(cp);
1246 	if (columns == 0)
1247 		columns = 80;	/* last resort */
1248 
1249 	DBG_LEAVE;
1250 	return (columns);
1251 }
1252 
1253 static int
1254 is_dev(const char *name)
1255 {
1256 	struct stat devstat;
1257 
1258 	if (stat(name, &devstat) != 0)
1259 		return (0);
1260 	if (!S_ISCHR(devstat.st_mode))
1261 		return (0);
1262 	return (1);
1263 }
1264 
1265 static const char *
1266 getdev(const char *name, struct statfs *statfsp)
1267 {
1268 	static char device[MAXPATHLEN];
1269 	const char *cp;
1270 
1271 	if (is_dev(name))
1272 		return (name);
1273 
1274 	cp = strrchr(name, '/');
1275 	if (cp == NULL) {
1276 		snprintf(device, sizeof(device), "%s%s", _PATH_DEV, name);
1277 		if (is_dev(device))
1278 			return (device);
1279 	}
1280 
1281 	if (statfsp != NULL)
1282 		return (statfsp->f_mntfromname);
1283 
1284 	return (NULL);
1285 }
1286 
1287 /*
1288  * growfs(8) is a utility which allows to increase the size of an existing
1289  * ufs file system. Currently this can only be done on unmounted file system.
1290  * It recognizes some command line options to specify the new desired size,
1291  * and it does some basic checkings. The old file system size is determined
1292  * and after some more checks like we can really access the new last block
1293  * on the disk etc. we calculate the new parameters for the superblock. After
1294  * having done this we just call growfs() which will do the work.
1295  * We still have to provide support for snapshots. Therefore we first have to
1296  * understand what data structures are always replicated in the snapshot on
1297  * creation, for all other blocks we touch during our procedure, we have to
1298  * keep the old blocks unchanged somewhere available for the snapshots. If we
1299  * are lucky, then we only have to handle our blocks to be relocated in that
1300  * way.
1301  * Also we have to consider in what order we actually update the critical
1302  * data structures of the file system to make sure, that in case of a disaster
1303  * fsck(8) is still able to restore any lost data.
1304  * The foreseen last step then will be to provide for growing even mounted
1305  * file systems. There we have to extend the mount() system call to provide
1306  * userland access to the file system locking facility.
1307  */
1308 int
1309 main(int argc, char **argv)
1310 {
1311 	DBG_FUNC("main")
1312 	struct fs *fs;
1313 	const char *device;
1314 	struct statfs *statfsp;
1315 	uint64_t size = 0;
1316 	off_t mediasize;
1317 	int error, j, fsi, fso, ch, ret, Nflag = 0, yflag = 0;
1318 	char *p, reply[5], oldsizebuf[6], newsizebuf[6];
1319 	void *testbuf;
1320 
1321 	DBG_ENTER;
1322 
1323 	while ((ch = getopt(argc, argv, "Ns:vy")) != -1) {
1324 		switch(ch) {
1325 		case 'N':
1326 			Nflag = 1;
1327 			break;
1328 		case 's':
1329 			size = (off_t)strtoumax(optarg, &p, 0);
1330 			if (p == NULL || *p == '\0')
1331 				size *= DEV_BSIZE;
1332 			else if (*p == 'b' || *p == 'B')
1333 				; /* do nothing */
1334 			else if (*p == 'k' || *p == 'K')
1335 				size <<= 10;
1336 			else if (*p == 'm' || *p == 'M')
1337 				size <<= 20;
1338 			else if (*p == 'g' || *p == 'G')
1339 				size <<= 30;
1340 			else if (*p == 't' || *p == 'T') {
1341 				size <<= 30;
1342 				size <<= 10;
1343 			} else
1344 				errx(1, "unknown suffix on -s argument");
1345 			break;
1346 		case 'v': /* for compatibility to newfs */
1347 			break;
1348 		case 'y':
1349 			yflag = 1;
1350 			break;
1351 		case '?':
1352 			/* FALLTHROUGH */
1353 		default:
1354 			usage();
1355 		}
1356 	}
1357 	argc -= optind;
1358 	argv += optind;
1359 
1360 	if (argc != 1)
1361 		usage();
1362 
1363 	/*
1364 	 * Now try to guess the device name.
1365 	 */
1366 	statfsp = getmntpoint(*argv);
1367 	device = getdev(*argv, statfsp);
1368 	if (device == NULL)
1369 		errx(1, "cannot find special device for %s", *argv);
1370 
1371 	fsi = open(device, O_RDONLY);
1372 	if (fsi < 0)
1373 		err(1, "%s", device);
1374 
1375 	/*
1376 	 * Try to guess the slice size if not specified.
1377 	 */
1378 	if (ioctl(fsi, DIOCGMEDIASIZE, &mediasize) == -1)
1379 		err(1,"DIOCGMEDIASIZE");
1380 
1381 	/*
1382 	 * Check if that partition is suitable for growing a file system.
1383 	 */
1384 	if (mediasize < 1)
1385 		errx(1, "partition is unavailable");
1386 
1387 	/*
1388 	 * Read the current superblock, and take a backup.
1389 	 */
1390 	if ((ret = sbget(fsi, &fs, UFS_STDSB, 0)) != 0) {
1391 		switch (ret) {
1392 		case ENOENT:
1393 			errx(1, "superblock not recognized");
1394 		default:
1395 			errc(1, ret, "unable to read superblock");
1396 		}
1397 	}
1398 	/*
1399 	 * Check for filesystem that was unclean at mount time.
1400 	 */
1401 	if ((fs->fs_flags & (FS_UNCLEAN | FS_NEEDSFSCK)) != 0)
1402 		errx(1, "%s is not clean - run fsck.\n", *argv);
1403 	memcpy(&osblock, fs, fs->fs_sbsize);
1404 	free(fs);
1405 	memcpy((void *)&fsun1, (void *)&fsun2, osblock.fs_sbsize);
1406 
1407 	DBG_OPEN("/tmp/growfs.debug"); /* already here we need a superblock */
1408 	DBG_DUMP_FS(&sblock, "old sblock");
1409 
1410 	/*
1411 	 * Determine size to grow to. Default to the device size.
1412 	 */
1413 	if (size == 0)
1414 		size = mediasize;
1415 	else {
1416 		if (size > (uint64_t)mediasize) {
1417 			humanize_number(oldsizebuf, sizeof(oldsizebuf), size,
1418 			    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1419 			humanize_number(newsizebuf, sizeof(newsizebuf),
1420 			    mediasize,
1421 			    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1422 
1423 			errx(1, "requested size %s is larger "
1424 			    "than the available %s", oldsizebuf, newsizebuf);
1425 		}
1426 	}
1427 
1428 	/*
1429 	 * Make sure the new size is a multiple of fs_fsize; /dev/ufssuspend
1430 	 * only supports fragment-aligned IO requests.
1431 	 */
1432 	size -= size % osblock.fs_fsize;
1433 
1434 	if (size <= (uint64_t)(osblock.fs_size * osblock.fs_fsize)) {
1435 		humanize_number(oldsizebuf, sizeof(oldsizebuf),
1436 		    osblock.fs_size * osblock.fs_fsize,
1437 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1438 		humanize_number(newsizebuf, sizeof(newsizebuf), size,
1439 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1440 
1441 		if (size == (uint64_t)(osblock.fs_size * osblock.fs_fsize))
1442 			errx(0, "requested size %s is equal to the current "
1443 			    "filesystem size %s", newsizebuf, oldsizebuf);
1444 		errx(1, "requested size %s is smaller than the current "
1445 		   "filesystem size %s", newsizebuf, oldsizebuf);
1446 	}
1447 
1448 	sblock.fs_old_size = sblock.fs_size =
1449 	    dbtofsb(&osblock, size / DEV_BSIZE);
1450 	sblock.fs_providersize = dbtofsb(&osblock, mediasize / DEV_BSIZE);
1451 
1452 	/*
1453 	 * Are we really growing?
1454 	 */
1455 	if (osblock.fs_size >= sblock.fs_size) {
1456 		errx(1, "we are not growing (%jd->%jd)",
1457 		    (intmax_t)osblock.fs_size, (intmax_t)sblock.fs_size);
1458 	}
1459 
1460 	/*
1461 	 * Check if we find an active snapshot.
1462 	 */
1463 	if (yflag == 0) {
1464 		for (j = 0; j < FSMAXSNAP; j++) {
1465 			if (sblock.fs_snapinum[j]) {
1466 				errx(1, "active snapshot found in file system; "
1467 				    "please remove all snapshots before "
1468 				    "using growfs");
1469 			}
1470 			if (!sblock.fs_snapinum[j]) /* list is dense */
1471 				break;
1472 		}
1473 	}
1474 
1475 	if (yflag == 0 && Nflag == 0) {
1476 		if (statfsp != NULL && (statfsp->f_flags & MNT_RDONLY) == 0)
1477 			printf("Device is mounted read-write; resizing will "
1478 			    "result in temporary write suspension for %s.\n",
1479 			    statfsp->f_mntonname);
1480 		printf("It's strongly recommended to make a backup "
1481 		    "before growing the file system.\n"
1482 		    "OK to grow filesystem on %s", device);
1483 		if (statfsp != NULL)
1484 			printf(", mounted on %s,", statfsp->f_mntonname);
1485 		humanize_number(oldsizebuf, sizeof(oldsizebuf),
1486 		    osblock.fs_size * osblock.fs_fsize,
1487 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1488 		humanize_number(newsizebuf, sizeof(newsizebuf),
1489 		    sblock.fs_size * sblock.fs_fsize,
1490 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1491 		printf(" from %s to %s? [yes/no] ", oldsizebuf, newsizebuf);
1492 		fflush(stdout);
1493 		fgets(reply, (int)sizeof(reply), stdin);
1494 		if (strcasecmp(reply, "yes\n")){
1495 			printf("Response other than \"yes\"; aborting\n");
1496 			exit(0);
1497 		}
1498 	}
1499 
1500 	/*
1501 	 * Try to access our device for writing.  If it's not mounted,
1502 	 * or mounted read-only, simply open it; otherwise, use UFS
1503 	 * suspension mechanism.
1504 	 */
1505 	if (Nflag) {
1506 		fso = -1;
1507 	} else {
1508 		if (statfsp != NULL && (statfsp->f_flags & MNT_RDONLY) == 0) {
1509 			fso = open(_PATH_UFSSUSPEND, O_RDWR);
1510 			if (fso == -1)
1511 				err(1, "unable to open %s", _PATH_UFSSUSPEND);
1512 			error = ioctl(fso, UFSSUSPEND, &statfsp->f_fsid);
1513 			if (error != 0)
1514 				err(1, "UFSSUSPEND");
1515 		} else {
1516 			fso = open(device, O_WRONLY);
1517 			if (fso < 0)
1518 				err(1, "%s", device);
1519 		}
1520 	}
1521 
1522 	/*
1523 	 * Try to access our new last block in the file system.
1524 	 */
1525 	testbuf = malloc(sblock.fs_fsize);
1526 	if (testbuf == NULL)
1527 		err(1, "malloc");
1528 	rdfs((ufs2_daddr_t)((size - sblock.fs_fsize) / DEV_BSIZE),
1529 	    sblock.fs_fsize, testbuf, fsi);
1530 	wtfs((ufs2_daddr_t)((size - sblock.fs_fsize) / DEV_BSIZE),
1531 	    sblock.fs_fsize, testbuf, fso, Nflag);
1532 	free(testbuf);
1533 
1534 	/*
1535 	 * Now calculate new superblock values and check for reasonable
1536 	 * bound for new file system size:
1537 	 *     fs_size:    is derived from user input
1538 	 *     fs_dsize:   should get updated in the routines creating or
1539 	 *                 updating the cylinder groups on the fly
1540 	 *     fs_cstotal: should get updated in the routines creating or
1541 	 *                 updating the cylinder groups
1542 	 */
1543 
1544 	/*
1545 	 * Update the number of cylinders and cylinder groups in the file system.
1546 	 */
1547 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
1548 		sblock.fs_old_ncyl =
1549 		    sblock.fs_size * sblock.fs_old_nspf / sblock.fs_old_spc;
1550 		if (sblock.fs_size * sblock.fs_old_nspf >
1551 		    sblock.fs_old_ncyl * sblock.fs_old_spc)
1552 			sblock.fs_old_ncyl++;
1553 	}
1554 	sblock.fs_ncg = howmany(sblock.fs_size, sblock.fs_fpg);
1555 
1556 	/*
1557 	 * Allocate last cylinder group only if there is enough room
1558 	 * for at least one data block.
1559 	 */
1560 	if (sblock.fs_size % sblock.fs_fpg != 0 &&
1561 	    sblock.fs_size <= cgdmin(&sblock, sblock.fs_ncg - 1)) {
1562 		humanize_number(oldsizebuf, sizeof(oldsizebuf),
1563 		    (sblock.fs_size % sblock.fs_fpg) * sblock.fs_fsize,
1564 		    "B", HN_AUTOSCALE, HN_B | HN_NOSPACE | HN_DECIMAL);
1565 		warnx("no room to allocate last cylinder group; "
1566 		    "leaving %s unused", oldsizebuf);
1567 		sblock.fs_ncg--;
1568 		if (sblock.fs_magic == FS_UFS1_MAGIC)
1569 			sblock.fs_old_ncyl = sblock.fs_ncg * sblock.fs_old_cpg;
1570 		sblock.fs_old_size = sblock.fs_size =
1571 		    sblock.fs_ncg * sblock.fs_fpg;
1572 	}
1573 
1574 	/*
1575 	 * Update the space for the cylinder group summary information in the
1576 	 * respective cylinder group data area.
1577 	 */
1578 	sblock.fs_cssize =
1579 	    fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));
1580 
1581 	if (osblock.fs_size >= sblock.fs_size)
1582 		errx(1, "not enough new space");
1583 
1584 	DBG_PRINT0("sblock calculated\n");
1585 
1586 	/*
1587 	 * Ok, everything prepared, so now let's do the tricks.
1588 	 */
1589 	growfs(fsi, fso, Nflag);
1590 
1591 	close(fsi);
1592 	if (fso > -1) {
1593 		if (statfsp != NULL && (statfsp->f_flags & MNT_RDONLY) == 0) {
1594 			error = ioctl(fso, UFSRESUME);
1595 			if (error != 0)
1596 				err(1, "UFSRESUME");
1597 		}
1598 		error = close(fso);
1599 		if (error != 0)
1600 			err(1, "close");
1601 		if (statfsp != NULL && (statfsp->f_flags & MNT_RDONLY) != 0 &&
1602 		    chkdoreload(statfsp, warn) != 0)
1603 			exit(9);
1604 	}
1605 
1606 	DBG_CLOSE;
1607 
1608 	DBG_LEAVE;
1609 	return (0);
1610 }
1611 
1612 /*
1613  * Dump a line of usage.
1614  */
1615 static void
1616 usage(void)
1617 {
1618 	DBG_FUNC("usage")
1619 
1620 	DBG_ENTER;
1621 
1622 	fprintf(stderr, "usage: growfs [-Ny] [-s size] special | filesystem\n");
1623 
1624 	DBG_LEAVE;
1625 	exit(1);
1626 }
1627 
1628 /*
1629  * This updates most parameters and the bitmap related to cluster. We have to
1630  * assume that sblock, osblock, acg are set up.
1631  */
1632 static void
1633 updclst(int block)
1634 {
1635 	DBG_FUNC("updclst")
1636 	static int lcs = 0;
1637 
1638 	DBG_ENTER;
1639 
1640 	if (sblock.fs_contigsumsize < 1) /* no clustering */
1641 		return;
1642 	/*
1643 	 * update cluster allocation map
1644 	 */
1645 	setbit(cg_clustersfree(&acg), block);
1646 
1647 	/*
1648 	 * update cluster summary table
1649 	 */
1650 	if (!lcs) {
1651 		/*
1652 		 * calculate size for the trailing cluster
1653 		 */
1654 		for (block--; lcs < sblock.fs_contigsumsize; block--, lcs++ ) {
1655 			if (isclr(cg_clustersfree(&acg), block))
1656 				break;
1657 		}
1658 	}
1659 	if (lcs < sblock.fs_contigsumsize) {
1660 		if (lcs)
1661 			cg_clustersum(&acg)[lcs]--;
1662 		lcs++;
1663 		cg_clustersum(&acg)[lcs]++;
1664 	}
1665 
1666 	DBG_LEAVE;
1667 	return;
1668 }
1669 
1670 /*
1671  * Calculate the check-hash of the cylinder group.
1672  */
1673 static void
1674 cgckhash(struct cg *cgp)
1675 {
1676 
1677 	if ((sblock.fs_metackhash & CK_CYLGRP) == 0)
1678 		return;
1679 	cgp->cg_ckhash = 0;
1680 	cgp->cg_ckhash = calculate_crc32c(~0L, (void *)cgp, sblock.fs_cgsize);
1681 }
1682