xref: /freebsd/sbin/newfs/mkfs.c (revision 7aa383846770374466b1dcb2cefd71bde9acf463)
1 /*
2  * Copyright (c) 2002 Networks Associates Technology, Inc.
3  * All rights reserved.
4  *
5  * This software was developed for the FreeBSD Project by Marshall
6  * Kirk McKusick and Network Associates Laboratories, the Security
7  * Research Division of Network Associates, Inc. under DARPA/SPAWAR
8  * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
9  * research program.
10  *
11  * Copyright (c) 1980, 1989, 1993
12  *	The Regents of the University of California.  All rights reserved.
13  *
14  * Redistribution and use in source and binary forms, with or without
15  * modification, are permitted provided that the following conditions
16  * are met:
17  * 1. Redistributions of source code must retain the above copyright
18  *    notice, this list of conditions and the following disclaimer.
19  * 2. Redistributions in binary form must reproduce the above copyright
20  *    notice, this list of conditions and the following disclaimer in the
21  *    documentation and/or other materials provided with the distribution.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  */
38 
39 #if 0
40 #ifndef lint
41 static char sccsid[] = "@(#)mkfs.c	8.11 (Berkeley) 5/3/95";
42 #endif /* not lint */
43 #endif
44 #include <sys/cdefs.h>
45 __FBSDID("$FreeBSD$");
46 
47 #include <err.h>
48 #include <grp.h>
49 #include <limits.h>
50 #include <signal.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <stdint.h>
54 #include <stdio.h>
55 #include <unistd.h>
56 #include <sys/param.h>
57 #include <sys/time.h>
58 #include <sys/types.h>
59 #include <sys/wait.h>
60 #include <sys/resource.h>
61 #include <sys/stat.h>
62 #include <ufs/ufs/dinode.h>
63 #include <ufs/ufs/dir.h>
64 #include <ufs/ffs/fs.h>
65 #include <sys/disklabel.h>
66 #include <sys/file.h>
67 #include <sys/mman.h>
68 #include <sys/ioctl.h>
69 #include "newfs.h"
70 
71 /*
72  * make file system for cylinder-group style file systems
73  */
74 #define UMASK		0755
75 #define POWEROF2(num)	(((num) & ((num) - 1)) == 0)
76 
77 static struct	csum *fscs;
78 #define	sblock	disk.d_fs
79 #define	acg	disk.d_cg
80 
81 union dinode {
82 	struct ufs1_dinode dp1;
83 	struct ufs2_dinode dp2;
84 };
85 #define DIP(dp, field) \
86 	((sblock.fs_magic == FS_UFS1_MAGIC) ? \
87 	(dp)->dp1.field : (dp)->dp2.field)
88 
89 static caddr_t iobuf;
90 static long iobufsize;
91 static ufs2_daddr_t alloc(int size, int mode);
92 static int charsperline(void);
93 static void clrblock(struct fs *, unsigned char *, int);
94 static void fsinit(time_t);
95 static int ilog2(int);
96 static void initcg(int, time_t);
97 static int isblock(struct fs *, unsigned char *, int);
98 static void iput(union dinode *, ino_t);
99 static int makedir(struct direct *, int);
100 static void setblock(struct fs *, unsigned char *, int);
101 static void wtfs(ufs2_daddr_t, int, char *);
102 static u_int32_t newfs_random(void);
103 
104 static int
105 do_sbwrite(struct uufsd *disk)
106 {
107 	if (!disk->d_sblock)
108 		disk->d_sblock = disk->d_fs.fs_sblockloc / disk->d_bsize;
109 	return (pwrite(disk->d_fd, &disk->d_fs, SBLOCKSIZE, (off_t)((part_ofs +
110 	    disk->d_sblock) * disk->d_bsize)));
111 }
112 
113 void
114 mkfs(struct partition *pp, char *fsys)
115 {
116 	int fragsperinode, optimalfpg, origdensity, minfpg, lastminfpg;
117 	long i, j, csfrags;
118 	uint cg;
119 	time_t utime;
120 	quad_t sizepb;
121 	int width;
122 	ino_t maxinum;
123 	int minfragsperinode;	/* minimum ratio of frags to inodes */
124 	char tmpbuf[100];	/* XXX this will break in about 2,500 years */
125 	union {
126 		struct fs fdummy;
127 		char cdummy[SBLOCKSIZE];
128 	} dummy;
129 #define fsdummy dummy.fdummy
130 #define chdummy dummy.cdummy
131 
132 	/*
133 	 * Our blocks == sector size, and the version of UFS we are using is
134 	 * specified by Oflag.
135 	 */
136 	disk.d_bsize = sectorsize;
137 	disk.d_ufs = Oflag;
138 	if (Rflag) {
139 		utime = 1000000000;
140 	} else {
141 		time(&utime);
142 		arc4random_stir();
143 	}
144 	sblock.fs_old_flags = FS_FLAGS_UPDATED;
145 	sblock.fs_flags = 0;
146 	if (Uflag)
147 		sblock.fs_flags |= FS_DOSOFTDEP;
148 	if (Lflag)
149 		strlcpy(sblock.fs_volname, volumelabel, MAXVOLLEN);
150 	if (Jflag)
151 		sblock.fs_flags |= FS_GJOURNAL;
152 	if (lflag)
153 		sblock.fs_flags |= FS_MULTILABEL;
154 	/*
155 	 * Validate the given file system size.
156 	 * Verify that its last block can actually be accessed.
157 	 * Convert to file system fragment sized units.
158 	 */
159 	if (fssize <= 0) {
160 		printf("preposterous size %jd\n", (intmax_t)fssize);
161 		exit(13);
162 	}
163 	wtfs(fssize - (realsectorsize / DEV_BSIZE), realsectorsize,
164 	    (char *)&sblock);
165 	/*
166 	 * collect and verify the file system density info
167 	 */
168 	sblock.fs_avgfilesize = avgfilesize;
169 	sblock.fs_avgfpdir = avgfilesperdir;
170 	if (sblock.fs_avgfilesize <= 0)
171 		printf("illegal expected average file size %d\n",
172 		    sblock.fs_avgfilesize), exit(14);
173 	if (sblock.fs_avgfpdir <= 0)
174 		printf("illegal expected number of files per directory %d\n",
175 		    sblock.fs_avgfpdir), exit(15);
176 
177 restart:
178 	/*
179 	 * collect and verify the block and fragment sizes
180 	 */
181 	sblock.fs_bsize = bsize;
182 	sblock.fs_fsize = fsize;
183 	if (!POWEROF2(sblock.fs_bsize)) {
184 		printf("block size must be a power of 2, not %d\n",
185 		    sblock.fs_bsize);
186 		exit(16);
187 	}
188 	if (!POWEROF2(sblock.fs_fsize)) {
189 		printf("fragment size must be a power of 2, not %d\n",
190 		    sblock.fs_fsize);
191 		exit(17);
192 	}
193 	if (sblock.fs_fsize < sectorsize) {
194 		printf("increasing fragment size from %d to sector size (%d)\n",
195 		    sblock.fs_fsize, sectorsize);
196 		sblock.fs_fsize = sectorsize;
197 	}
198 	if (sblock.fs_bsize > MAXBSIZE) {
199 		printf("decreasing block size from %d to maximum (%d)\n",
200 		    sblock.fs_bsize, MAXBSIZE);
201 		sblock.fs_bsize = MAXBSIZE;
202 	}
203 	if (sblock.fs_bsize < MINBSIZE) {
204 		printf("increasing block size from %d to minimum (%d)\n",
205 		    sblock.fs_bsize, MINBSIZE);
206 		sblock.fs_bsize = MINBSIZE;
207 	}
208 	if (sblock.fs_fsize > MAXBSIZE) {
209 		printf("decreasing fragment size from %d to maximum (%d)\n",
210 		    sblock.fs_fsize, MAXBSIZE);
211 		sblock.fs_fsize = MAXBSIZE;
212 	}
213 	if (sblock.fs_bsize < sblock.fs_fsize) {
214 		printf("increasing block size from %d to fragment size (%d)\n",
215 		    sblock.fs_bsize, sblock.fs_fsize);
216 		sblock.fs_bsize = sblock.fs_fsize;
217 	}
218 	if (sblock.fs_fsize * MAXFRAG < sblock.fs_bsize) {
219 		printf(
220 		"increasing fragment size from %d to block size / %d (%d)\n",
221 		    sblock.fs_fsize, MAXFRAG, sblock.fs_bsize / MAXFRAG);
222 		sblock.fs_fsize = sblock.fs_bsize / MAXFRAG;
223 	}
224 	if (maxbsize == 0)
225 		maxbsize = bsize;
226 	if (maxbsize < bsize || !POWEROF2(maxbsize)) {
227 		sblock.fs_maxbsize = sblock.fs_bsize;
228 		printf("Extent size set to %d\n", sblock.fs_maxbsize);
229 	} else if (sblock.fs_maxbsize > FS_MAXCONTIG * sblock.fs_bsize) {
230 		sblock.fs_maxbsize = FS_MAXCONTIG * sblock.fs_bsize;
231 		printf("Extent size reduced to %d\n", sblock.fs_maxbsize);
232 	} else {
233 		sblock.fs_maxbsize = maxbsize;
234 	}
235 	/*
236 	 * Maxcontig sets the default for the maximum number of blocks
237 	 * that may be allocated sequentially. With file system clustering
238 	 * it is possible to allocate contiguous blocks up to the maximum
239 	 * transfer size permitted by the controller or buffering.
240 	 */
241 	if (maxcontig == 0)
242 		maxcontig = MAX(1, MAXPHYS / bsize);
243 	sblock.fs_maxcontig = maxcontig;
244 	if (sblock.fs_maxcontig < sblock.fs_maxbsize / sblock.fs_bsize) {
245 		sblock.fs_maxcontig = sblock.fs_maxbsize / sblock.fs_bsize;
246 		printf("Maxcontig raised to %d\n", sblock.fs_maxbsize);
247 	}
248 	if (sblock.fs_maxcontig > 1)
249 		sblock.fs_contigsumsize = MIN(sblock.fs_maxcontig,FS_MAXCONTIG);
250 	sblock.fs_bmask = ~(sblock.fs_bsize - 1);
251 	sblock.fs_fmask = ~(sblock.fs_fsize - 1);
252 	sblock.fs_qbmask = ~sblock.fs_bmask;
253 	sblock.fs_qfmask = ~sblock.fs_fmask;
254 	sblock.fs_bshift = ilog2(sblock.fs_bsize);
255 	sblock.fs_fshift = ilog2(sblock.fs_fsize);
256 	sblock.fs_frag = numfrags(&sblock, sblock.fs_bsize);
257 	sblock.fs_fragshift = ilog2(sblock.fs_frag);
258 	if (sblock.fs_frag > MAXFRAG) {
259 		printf("fragment size %d is still too small (can't happen)\n",
260 		    sblock.fs_bsize / MAXFRAG);
261 		exit(21);
262 	}
263 	sblock.fs_fsbtodb = ilog2(sblock.fs_fsize / sectorsize);
264 	sblock.fs_size = fssize = dbtofsb(&sblock, fssize);
265 
266 	/*
267 	 * Before the filesystem is finally initialized, mark it
268 	 * as incompletely initialized.
269 	 */
270 	sblock.fs_magic = FS_BAD_MAGIC;
271 
272 	if (Oflag == 1) {
273 		sblock.fs_sblockloc = SBLOCK_UFS1;
274 		sblock.fs_nindir = sblock.fs_bsize / sizeof(ufs1_daddr_t);
275 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs1_dinode);
276 		sblock.fs_maxsymlinklen = ((NDADDR + NIADDR) *
277 		    sizeof(ufs1_daddr_t));
278 		sblock.fs_old_inodefmt = FS_44INODEFMT;
279 		sblock.fs_old_cgoffset = 0;
280 		sblock.fs_old_cgmask = 0xffffffff;
281 		sblock.fs_old_size = sblock.fs_size;
282 		sblock.fs_old_rotdelay = 0;
283 		sblock.fs_old_rps = 60;
284 		sblock.fs_old_nspf = sblock.fs_fsize / sectorsize;
285 		sblock.fs_old_cpg = 1;
286 		sblock.fs_old_interleave = 1;
287 		sblock.fs_old_trackskew = 0;
288 		sblock.fs_old_cpc = 0;
289 		sblock.fs_old_postblformat = 1;
290 		sblock.fs_old_nrpos = 1;
291 	} else {
292 		sblock.fs_sblockloc = SBLOCK_UFS2;
293 		sblock.fs_nindir = sblock.fs_bsize / sizeof(ufs2_daddr_t);
294 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs2_dinode);
295 		sblock.fs_maxsymlinklen = ((NDADDR + NIADDR) *
296 		    sizeof(ufs2_daddr_t));
297 	}
298 	sblock.fs_sblkno =
299 	    roundup(howmany(sblock.fs_sblockloc + SBLOCKSIZE, sblock.fs_fsize),
300 		sblock.fs_frag);
301 	sblock.fs_cblkno = sblock.fs_sblkno +
302 	    roundup(howmany(SBLOCKSIZE, sblock.fs_fsize), sblock.fs_frag);
303 	sblock.fs_iblkno = sblock.fs_cblkno + sblock.fs_frag;
304 	sblock.fs_maxfilesize = sblock.fs_bsize * NDADDR - 1;
305 	for (sizepb = sblock.fs_bsize, i = 0; i < NIADDR; i++) {
306 		sizepb *= NINDIR(&sblock);
307 		sblock.fs_maxfilesize += sizepb;
308 	}
309 
310 	/*
311 	 * It's impossible to create a snapshot in case that fs_maxfilesize
312 	 * is smaller than the fssize.
313 	 */
314 	if (sblock.fs_maxfilesize < (u_quad_t)fssize) {
315 		warnx("WARNING: You will be unable to create snapshots on this "
316 		      "file system.  Correct by using a larger blocksize.");
317 	}
318 
319 	/*
320 	 * Calculate the number of blocks to put into each cylinder group.
321 	 *
322 	 * This algorithm selects the number of blocks per cylinder
323 	 * group. The first goal is to have at least enough data blocks
324 	 * in each cylinder group to meet the density requirement. Once
325 	 * this goal is achieved we try to expand to have at least
326 	 * MINCYLGRPS cylinder groups. Once this goal is achieved, we
327 	 * pack as many blocks into each cylinder group map as will fit.
328 	 *
329 	 * We start by calculating the smallest number of blocks that we
330 	 * can put into each cylinder group. If this is too big, we reduce
331 	 * the density until it fits.
332 	 */
333 	maxinum = (((int64_t)(1)) << 32) - INOPB(&sblock);
334 	minfragsperinode = 1 + fssize / maxinum;
335 	if (density == 0) {
336 		density = MAX(NFPI, minfragsperinode) * fsize;
337 	} else if (density < minfragsperinode * fsize) {
338 		origdensity = density;
339 		density = minfragsperinode * fsize;
340 		fprintf(stderr, "density increased from %d to %d\n",
341 		    origdensity, density);
342 	}
343 	origdensity = density;
344 	for (;;) {
345 		fragsperinode = MAX(numfrags(&sblock, density), 1);
346 		if (fragsperinode < minfragsperinode) {
347 			bsize <<= 1;
348 			fsize <<= 1;
349 			printf("Block size too small for a file system %s %d\n",
350 			     "of this size. Increasing blocksize to", bsize);
351 			goto restart;
352 		}
353 		minfpg = fragsperinode * INOPB(&sblock);
354 		if (minfpg > sblock.fs_size)
355 			minfpg = sblock.fs_size;
356 		sblock.fs_ipg = INOPB(&sblock);
357 		sblock.fs_fpg = roundup(sblock.fs_iblkno +
358 		    sblock.fs_ipg / INOPF(&sblock), sblock.fs_frag);
359 		if (sblock.fs_fpg < minfpg)
360 			sblock.fs_fpg = minfpg;
361 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
362 		    INOPB(&sblock));
363 		sblock.fs_fpg = roundup(sblock.fs_iblkno +
364 		    sblock.fs_ipg / INOPF(&sblock), sblock.fs_frag);
365 		if (sblock.fs_fpg < minfpg)
366 			sblock.fs_fpg = minfpg;
367 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
368 		    INOPB(&sblock));
369 		if (CGSIZE(&sblock) < (unsigned long)sblock.fs_bsize)
370 			break;
371 		density -= sblock.fs_fsize;
372 	}
373 	if (density != origdensity)
374 		printf("density reduced from %d to %d\n", origdensity, density);
375 	/*
376 	 * Start packing more blocks into the cylinder group until
377 	 * it cannot grow any larger, the number of cylinder groups
378 	 * drops below MINCYLGRPS, or we reach the size requested.
379 	 */
380 	for ( ; sblock.fs_fpg < maxblkspercg; sblock.fs_fpg += sblock.fs_frag) {
381 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
382 		    INOPB(&sblock));
383 		if (sblock.fs_size / sblock.fs_fpg < MINCYLGRPS)
384 			break;
385 		if (CGSIZE(&sblock) < (unsigned long)sblock.fs_bsize)
386 			continue;
387 		if (CGSIZE(&sblock) == (unsigned long)sblock.fs_bsize)
388 			break;
389 		sblock.fs_fpg -= sblock.fs_frag;
390 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
391 		    INOPB(&sblock));
392 		break;
393 	}
394 	/*
395 	 * Check to be sure that the last cylinder group has enough blocks
396 	 * to be viable. If it is too small, reduce the number of blocks
397 	 * per cylinder group which will have the effect of moving more
398 	 * blocks into the last cylinder group.
399 	 */
400 	optimalfpg = sblock.fs_fpg;
401 	for (;;) {
402 		sblock.fs_ncg = howmany(sblock.fs_size, sblock.fs_fpg);
403 		lastminfpg = roundup(sblock.fs_iblkno +
404 		    sblock.fs_ipg / INOPF(&sblock), sblock.fs_frag);
405 		if (sblock.fs_size < lastminfpg) {
406 			printf("Filesystem size %jd < minimum size of %d\n",
407 			    (intmax_t)sblock.fs_size, lastminfpg);
408 			exit(28);
409 		}
410 		if (sblock.fs_size % sblock.fs_fpg >= lastminfpg ||
411 		    sblock.fs_size % sblock.fs_fpg == 0)
412 			break;
413 		sblock.fs_fpg -= sblock.fs_frag;
414 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
415 		    INOPB(&sblock));
416 	}
417 	if (optimalfpg != sblock.fs_fpg)
418 		printf("Reduced frags per cylinder group from %d to %d %s\n",
419 		   optimalfpg, sblock.fs_fpg, "to enlarge last cyl group");
420 	sblock.fs_cgsize = fragroundup(&sblock, CGSIZE(&sblock));
421 	sblock.fs_dblkno = sblock.fs_iblkno + sblock.fs_ipg / INOPF(&sblock);
422 	if (Oflag == 1) {
423 		sblock.fs_old_spc = sblock.fs_fpg * sblock.fs_old_nspf;
424 		sblock.fs_old_nsect = sblock.fs_old_spc;
425 		sblock.fs_old_npsect = sblock.fs_old_spc;
426 		sblock.fs_old_ncyl = sblock.fs_ncg;
427 	}
428 	/*
429 	 * fill in remaining fields of the super block
430 	 */
431 	sblock.fs_csaddr = cgdmin(&sblock, 0);
432 	sblock.fs_cssize =
433 	    fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));
434 	fscs = (struct csum *)calloc(1, sblock.fs_cssize);
435 	if (fscs == NULL)
436 		errx(31, "calloc failed");
437 	sblock.fs_sbsize = fragroundup(&sblock, sizeof(struct fs));
438 	if (sblock.fs_sbsize > SBLOCKSIZE)
439 		sblock.fs_sbsize = SBLOCKSIZE;
440 	sblock.fs_minfree = minfree;
441 	if (maxbpg == 0)
442 		sblock.fs_maxbpg = MAXBLKPG(sblock.fs_bsize);
443 	else
444 		sblock.fs_maxbpg = maxbpg;
445 	sblock.fs_optim = opt;
446 	sblock.fs_cgrotor = 0;
447 	sblock.fs_pendingblocks = 0;
448 	sblock.fs_pendinginodes = 0;
449 	sblock.fs_fmod = 0;
450 	sblock.fs_ronly = 0;
451 	sblock.fs_state = 0;
452 	sblock.fs_clean = 1;
453 	sblock.fs_id[0] = (long)utime;
454 	sblock.fs_id[1] = newfs_random();
455 	sblock.fs_fsmnt[0] = '\0';
456 	csfrags = howmany(sblock.fs_cssize, sblock.fs_fsize);
457 	sblock.fs_dsize = sblock.fs_size - sblock.fs_sblkno -
458 	    sblock.fs_ncg * (sblock.fs_dblkno - sblock.fs_sblkno);
459 	sblock.fs_cstotal.cs_nbfree =
460 	    fragstoblks(&sblock, sblock.fs_dsize) -
461 	    howmany(csfrags, sblock.fs_frag);
462 	sblock.fs_cstotal.cs_nffree =
463 	    fragnum(&sblock, sblock.fs_size) +
464 	    (fragnum(&sblock, csfrags) > 0 ?
465 	     sblock.fs_frag - fragnum(&sblock, csfrags) : 0);
466 	sblock.fs_cstotal.cs_nifree = sblock.fs_ncg * sblock.fs_ipg - ROOTINO;
467 	sblock.fs_cstotal.cs_ndir = 0;
468 	sblock.fs_dsize -= csfrags;
469 	sblock.fs_time = utime;
470 	if (Oflag == 1) {
471 		sblock.fs_old_time = utime;
472 		sblock.fs_old_dsize = sblock.fs_dsize;
473 		sblock.fs_old_csaddr = sblock.fs_csaddr;
474 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
475 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
476 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
477 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
478 	}
479 
480 	/*
481 	 * Dump out summary information about file system.
482 	 */
483 #	define B2MBFACTOR (1 / (1024.0 * 1024.0))
484 	printf("%s: %.1fMB (%jd sectors) block size %d, fragment size %d\n",
485 	    fsys, (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
486 	    (intmax_t)fsbtodb(&sblock, sblock.fs_size), sblock.fs_bsize,
487 	    sblock.fs_fsize);
488 	printf("\tusing %d cylinder groups of %.2fMB, %d blks, %d inodes.\n",
489 	    sblock.fs_ncg, (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
490 	    sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
491 	if (sblock.fs_flags & FS_DOSOFTDEP)
492 		printf("\twith soft updates\n");
493 #	undef B2MBFACTOR
494 
495 	if (Eflag && !Nflag) {
496 		printf("Erasing sectors [%jd...%jd]\n",
497 		    sblock.fs_sblockloc / disk.d_bsize,
498 		    fsbtodb(&sblock, sblock.fs_size) - 1);
499 		berase(&disk, sblock.fs_sblockloc / disk.d_bsize,
500 		    sblock.fs_size * sblock.fs_fsize - sblock.fs_sblockloc);
501 	}
502 	/*
503 	 * Wipe out old UFS1 superblock(s) if necessary.
504 	 */
505 	if (!Nflag && Oflag != 1) {
506 		i = bread(&disk, part_ofs + SBLOCK_UFS1 / disk.d_bsize, chdummy, SBLOCKSIZE);
507 		if (i == -1)
508 			err(1, "can't read old UFS1 superblock: %s", disk.d_error);
509 
510 		if (fsdummy.fs_magic == FS_UFS1_MAGIC) {
511 			fsdummy.fs_magic = 0;
512 			bwrite(&disk, part_ofs + SBLOCK_UFS1 / disk.d_bsize,
513 			    chdummy, SBLOCKSIZE);
514 			for (cg = 0; cg < fsdummy.fs_ncg; cg++)
515 				bwrite(&disk, part_ofs + fsbtodb(&fsdummy,
516 				  cgsblock(&fsdummy, cg)), chdummy, SBLOCKSIZE);
517 		}
518 	}
519 	if (!Nflag)
520 		do_sbwrite(&disk);
521 	if (Xflag == 1) {
522 		printf("** Exiting on Xflag 1\n");
523 		exit(0);
524 	}
525 	if (Xflag == 2)
526 		printf("** Leaving BAD MAGIC on Xflag 2\n");
527 	else
528 		sblock.fs_magic = (Oflag != 1) ? FS_UFS2_MAGIC : FS_UFS1_MAGIC;
529 
530 	/*
531 	 * Now build the cylinders group blocks and
532 	 * then print out indices of cylinder groups.
533 	 */
534 	printf("super-block backups (for fsck -b #) at:\n");
535 	i = 0;
536 	width = charsperline();
537 	/*
538 	 * allocate space for superblock, cylinder group map, and
539 	 * two sets of inode blocks.
540 	 */
541 	if (sblock.fs_bsize < SBLOCKSIZE)
542 		iobufsize = SBLOCKSIZE + 3 * sblock.fs_bsize;
543 	else
544 		iobufsize = 4 * sblock.fs_bsize;
545 	if ((iobuf = calloc(1, iobufsize)) == 0) {
546 		printf("Cannot allocate I/O buffer\n");
547 		exit(38);
548 	}
549 	/*
550 	 * Make a copy of the superblock into the buffer that we will be
551 	 * writing out in each cylinder group.
552 	 */
553 	bcopy((char *)&sblock, iobuf, SBLOCKSIZE);
554 	for (cg = 0; cg < sblock.fs_ncg; cg++) {
555 		initcg(cg, utime);
556 		j = snprintf(tmpbuf, sizeof(tmpbuf), " %jd%s",
557 		    (intmax_t)fsbtodb(&sblock, cgsblock(&sblock, cg)),
558 		    cg < (sblock.fs_ncg-1) ? "," : "");
559 		if (j < 0)
560 			tmpbuf[j = 0] = '\0';
561 		if (i + j >= width) {
562 			printf("\n");
563 			i = 0;
564 		}
565 		i += j;
566 		printf("%s", tmpbuf);
567 		fflush(stdout);
568 	}
569 	printf("\n");
570 	if (Nflag)
571 		exit(0);
572 	/*
573 	 * Now construct the initial file system,
574 	 * then write out the super-block.
575 	 */
576 	fsinit(utime);
577 	if (Oflag == 1) {
578 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
579 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
580 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
581 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
582 	}
583 	if (Xflag == 3) {
584 		printf("** Exiting on Xflag 3\n");
585 		exit(0);
586 	}
587 	if (!Nflag)
588 		do_sbwrite(&disk);
589 	for (i = 0; i < sblock.fs_cssize; i += sblock.fs_bsize)
590 		wtfs(fsbtodb(&sblock, sblock.fs_csaddr + numfrags(&sblock, i)),
591 			sblock.fs_cssize - i < sblock.fs_bsize ?
592 			sblock.fs_cssize - i : sblock.fs_bsize,
593 			((char *)fscs) + i);
594 	/*
595 	 * Update information about this partition in pack
596 	 * label, to that it may be updated on disk.
597 	 */
598 	if (pp != NULL) {
599 		pp->p_fstype = FS_BSDFFS;
600 		pp->p_fsize = sblock.fs_fsize;
601 		pp->p_frag = sblock.fs_frag;
602 		pp->p_cpg = sblock.fs_fpg;
603 	}
604 }
605 
606 /*
607  * Initialize a cylinder group.
608  */
609 void
610 initcg(int cylno, time_t utime)
611 {
612 	long blkno, start;
613 	uint i, j, d, dlower, dupper;
614 	ufs2_daddr_t cbase, dmax;
615 	struct ufs1_dinode *dp1;
616 	struct ufs2_dinode *dp2;
617 	struct csum *cs;
618 
619 	/*
620 	 * Determine block bounds for cylinder group.
621 	 * Allow space for super block summary information in first
622 	 * cylinder group.
623 	 */
624 	cbase = cgbase(&sblock, cylno);
625 	dmax = cbase + sblock.fs_fpg;
626 	if (dmax > sblock.fs_size)
627 		dmax = sblock.fs_size;
628 	dlower = cgsblock(&sblock, cylno) - cbase;
629 	dupper = cgdmin(&sblock, cylno) - cbase;
630 	if (cylno == 0)
631 		dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
632 	cs = &fscs[cylno];
633 	memset(&acg, 0, sblock.fs_cgsize);
634 	acg.cg_time = utime;
635 	acg.cg_magic = CG_MAGIC;
636 	acg.cg_cgx = cylno;
637 	acg.cg_niblk = sblock.fs_ipg;
638 	acg.cg_initediblk = sblock.fs_ipg < 2 * INOPB(&sblock) ?
639 	    sblock.fs_ipg : 2 * INOPB(&sblock);
640 	acg.cg_ndblk = dmax - cbase;
641 	if (sblock.fs_contigsumsize > 0)
642 		acg.cg_nclusterblks = acg.cg_ndblk / sblock.fs_frag;
643 	start = &acg.cg_space[0] - (u_char *)(&acg.cg_firstfield);
644 	if (Oflag == 2) {
645 		acg.cg_iusedoff = start;
646 	} else {
647 		acg.cg_old_ncyl = sblock.fs_old_cpg;
648 		acg.cg_old_time = acg.cg_time;
649 		acg.cg_time = 0;
650 		acg.cg_old_niblk = acg.cg_niblk;
651 		acg.cg_niblk = 0;
652 		acg.cg_initediblk = 0;
653 		acg.cg_old_btotoff = start;
654 		acg.cg_old_boff = acg.cg_old_btotoff +
655 		    sblock.fs_old_cpg * sizeof(int32_t);
656 		acg.cg_iusedoff = acg.cg_old_boff +
657 		    sblock.fs_old_cpg * sizeof(u_int16_t);
658 	}
659 	acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
660 	acg.cg_nextfreeoff = acg.cg_freeoff + howmany(sblock.fs_fpg, CHAR_BIT);
661 	if (sblock.fs_contigsumsize > 0) {
662 		acg.cg_clustersumoff =
663 		    roundup(acg.cg_nextfreeoff, sizeof(u_int32_t));
664 		acg.cg_clustersumoff -= sizeof(u_int32_t);
665 		acg.cg_clusteroff = acg.cg_clustersumoff +
666 		    (sblock.fs_contigsumsize + 1) * sizeof(u_int32_t);
667 		acg.cg_nextfreeoff = acg.cg_clusteroff +
668 		    howmany(fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
669 	}
670 	if (acg.cg_nextfreeoff > (unsigned)sblock.fs_cgsize) {
671 		printf("Panic: cylinder group too big\n");
672 		exit(37);
673 	}
674 	acg.cg_cs.cs_nifree += sblock.fs_ipg;
675 	if (cylno == 0)
676 		for (i = 0; i < (long)ROOTINO; i++) {
677 			setbit(cg_inosused(&acg), i);
678 			acg.cg_cs.cs_nifree--;
679 		}
680 	if (cylno > 0) {
681 		/*
682 		 * In cylno 0, beginning space is reserved
683 		 * for boot and super blocks.
684 		 */
685 		for (d = 0; d < dlower; d += sblock.fs_frag) {
686 			blkno = d / sblock.fs_frag;
687 			setblock(&sblock, cg_blksfree(&acg), blkno);
688 			if (sblock.fs_contigsumsize > 0)
689 				setbit(cg_clustersfree(&acg), blkno);
690 			acg.cg_cs.cs_nbfree++;
691 		}
692 	}
693 	if ((i = dupper % sblock.fs_frag)) {
694 		acg.cg_frsum[sblock.fs_frag - i]++;
695 		for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
696 			setbit(cg_blksfree(&acg), dupper);
697 			acg.cg_cs.cs_nffree++;
698 		}
699 	}
700 	for (d = dupper; d + sblock.fs_frag <= acg.cg_ndblk;
701 	     d += sblock.fs_frag) {
702 		blkno = d / sblock.fs_frag;
703 		setblock(&sblock, cg_blksfree(&acg), blkno);
704 		if (sblock.fs_contigsumsize > 0)
705 			setbit(cg_clustersfree(&acg), blkno);
706 		acg.cg_cs.cs_nbfree++;
707 	}
708 	if (d < acg.cg_ndblk) {
709 		acg.cg_frsum[acg.cg_ndblk - d]++;
710 		for (; d < acg.cg_ndblk; d++) {
711 			setbit(cg_blksfree(&acg), d);
712 			acg.cg_cs.cs_nffree++;
713 		}
714 	}
715 	if (sblock.fs_contigsumsize > 0) {
716 		int32_t *sump = cg_clustersum(&acg);
717 		u_char *mapp = cg_clustersfree(&acg);
718 		int map = *mapp++;
719 		int bit = 1;
720 		int run = 0;
721 
722 		for (i = 0; i < acg.cg_nclusterblks; i++) {
723 			if ((map & bit) != 0)
724 				run++;
725 			else if (run != 0) {
726 				if (run > sblock.fs_contigsumsize)
727 					run = sblock.fs_contigsumsize;
728 				sump[run]++;
729 				run = 0;
730 			}
731 			if ((i & (CHAR_BIT - 1)) != CHAR_BIT - 1)
732 				bit <<= 1;
733 			else {
734 				map = *mapp++;
735 				bit = 1;
736 			}
737 		}
738 		if (run != 0) {
739 			if (run > sblock.fs_contigsumsize)
740 				run = sblock.fs_contigsumsize;
741 			sump[run]++;
742 		}
743 	}
744 	*cs = acg.cg_cs;
745 	/*
746 	 * Write out the duplicate super block, the cylinder group map
747 	 * and two blocks worth of inodes in a single write.
748 	 */
749 	start = sblock.fs_bsize > SBLOCKSIZE ? sblock.fs_bsize : SBLOCKSIZE;
750 	bcopy((char *)&acg, &iobuf[start], sblock.fs_cgsize);
751 	start += sblock.fs_bsize;
752 	dp1 = (struct ufs1_dinode *)(&iobuf[start]);
753 	dp2 = (struct ufs2_dinode *)(&iobuf[start]);
754 	for (i = 0; i < acg.cg_initediblk; i++) {
755 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
756 			dp1->di_gen = newfs_random();
757 			dp1++;
758 		} else {
759 			dp2->di_gen = newfs_random();
760 			dp2++;
761 		}
762 	}
763 	wtfs(fsbtodb(&sblock, cgsblock(&sblock, cylno)), iobufsize, iobuf);
764 	/*
765 	 * For the old file system, we have to initialize all the inodes.
766 	 */
767 	if (Oflag == 1) {
768 		for (i = 2 * sblock.fs_frag;
769 		     i < sblock.fs_ipg / INOPF(&sblock);
770 		     i += sblock.fs_frag) {
771 			dp1 = (struct ufs1_dinode *)(&iobuf[start]);
772 			for (j = 0; j < INOPB(&sblock); j++) {
773 				dp1->di_gen = newfs_random();
774 				dp1++;
775 			}
776 			wtfs(fsbtodb(&sblock, cgimin(&sblock, cylno) + i),
777 			    sblock.fs_bsize, &iobuf[start]);
778 		}
779 	}
780 }
781 
782 /*
783  * initialize the file system
784  */
785 #define ROOTLINKCNT 3
786 
787 struct direct root_dir[] = {
788 	{ ROOTINO, sizeof(struct direct), DT_DIR, 1, "." },
789 	{ ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
790 	{ ROOTINO + 1, sizeof(struct direct), DT_DIR, 5, ".snap" },
791 };
792 
793 #define SNAPLINKCNT 2
794 
795 struct direct snap_dir[] = {
796 	{ ROOTINO + 1, sizeof(struct direct), DT_DIR, 1, "." },
797 	{ ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
798 };
799 
800 void
801 fsinit(time_t utime)
802 {
803 	union dinode node;
804 	struct group *grp;
805 	gid_t gid;
806 	int entries;
807 
808 	memset(&node, 0, sizeof node);
809 	if ((grp = getgrnam("operator")) != NULL) {
810 		gid = grp->gr_gid;
811 	} else {
812 		warnx("Cannot retrieve operator gid, using gid 0.");
813 		gid = 0;
814 	}
815 	entries = (nflag) ? ROOTLINKCNT - 1: ROOTLINKCNT;
816 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
817 		/*
818 		 * initialize the node
819 		 */
820 		node.dp1.di_atime = utime;
821 		node.dp1.di_mtime = utime;
822 		node.dp1.di_ctime = utime;
823 		/*
824 		 * create the root directory
825 		 */
826 		node.dp1.di_mode = IFDIR | UMASK;
827 		node.dp1.di_nlink = entries;
828 		node.dp1.di_size = makedir(root_dir, entries);
829 		node.dp1.di_db[0] = alloc(sblock.fs_fsize, node.dp1.di_mode);
830 		node.dp1.di_blocks =
831 		    btodb(fragroundup(&sblock, node.dp1.di_size));
832 		wtfs(fsbtodb(&sblock, node.dp1.di_db[0]), sblock.fs_fsize,
833 		    iobuf);
834 		iput(&node, ROOTINO);
835 		if (!nflag) {
836 			/*
837 			 * create the .snap directory
838 			 */
839 			node.dp1.di_mode |= 020;
840 			node.dp1.di_gid = gid;
841 			node.dp1.di_nlink = SNAPLINKCNT;
842 			node.dp1.di_size = makedir(snap_dir, SNAPLINKCNT);
843 				node.dp1.di_db[0] =
844 				    alloc(sblock.fs_fsize, node.dp1.di_mode);
845 			node.dp1.di_blocks =
846 			    btodb(fragroundup(&sblock, node.dp1.di_size));
847 				wtfs(fsbtodb(&sblock, node.dp1.di_db[0]),
848 				    sblock.fs_fsize, iobuf);
849 			iput(&node, ROOTINO + 1);
850 		}
851 	} else {
852 		/*
853 		 * initialize the node
854 		 */
855 		node.dp2.di_atime = utime;
856 		node.dp2.di_mtime = utime;
857 		node.dp2.di_ctime = utime;
858 		node.dp2.di_birthtime = utime;
859 		/*
860 		 * create the root directory
861 		 */
862 		node.dp2.di_mode = IFDIR | UMASK;
863 		node.dp2.di_nlink = entries;
864 		node.dp2.di_size = makedir(root_dir, entries);
865 		node.dp2.di_db[0] = alloc(sblock.fs_fsize, node.dp2.di_mode);
866 		node.dp2.di_blocks =
867 		    btodb(fragroundup(&sblock, node.dp2.di_size));
868 		wtfs(fsbtodb(&sblock, node.dp2.di_db[0]), sblock.fs_fsize,
869 		    iobuf);
870 		iput(&node, ROOTINO);
871 		if (!nflag) {
872 			/*
873 			 * create the .snap directory
874 			 */
875 			node.dp2.di_mode |= 020;
876 			node.dp2.di_gid = gid;
877 			node.dp2.di_nlink = SNAPLINKCNT;
878 			node.dp2.di_size = makedir(snap_dir, SNAPLINKCNT);
879 				node.dp2.di_db[0] =
880 				    alloc(sblock.fs_fsize, node.dp2.di_mode);
881 			node.dp2.di_blocks =
882 			    btodb(fragroundup(&sblock, node.dp2.di_size));
883 				wtfs(fsbtodb(&sblock, node.dp2.di_db[0]),
884 				    sblock.fs_fsize, iobuf);
885 			iput(&node, ROOTINO + 1);
886 		}
887 	}
888 }
889 
890 /*
891  * construct a set of directory entries in "iobuf".
892  * return size of directory.
893  */
894 int
895 makedir(struct direct *protodir, int entries)
896 {
897 	char *cp;
898 	int i, spcleft;
899 
900 	spcleft = DIRBLKSIZ;
901 	memset(iobuf, 0, DIRBLKSIZ);
902 	for (cp = iobuf, i = 0; i < entries - 1; i++) {
903 		protodir[i].d_reclen = DIRSIZ(0, &protodir[i]);
904 		memmove(cp, &protodir[i], protodir[i].d_reclen);
905 		cp += protodir[i].d_reclen;
906 		spcleft -= protodir[i].d_reclen;
907 	}
908 	protodir[i].d_reclen = spcleft;
909 	memmove(cp, &protodir[i], DIRSIZ(0, &protodir[i]));
910 	return (DIRBLKSIZ);
911 }
912 
913 /*
914  * allocate a block or frag
915  */
916 ufs2_daddr_t
917 alloc(int size, int mode)
918 {
919 	int i, blkno, frag;
920 	uint d;
921 
922 	bread(&disk, part_ofs + fsbtodb(&sblock, cgtod(&sblock, 0)), (char *)&acg,
923 	    sblock.fs_cgsize);
924 	if (acg.cg_magic != CG_MAGIC) {
925 		printf("cg 0: bad magic number\n");
926 		exit(38);
927 	}
928 	if (acg.cg_cs.cs_nbfree == 0) {
929 		printf("first cylinder group ran out of space\n");
930 		exit(39);
931 	}
932 	for (d = 0; d < acg.cg_ndblk; d += sblock.fs_frag)
933 		if (isblock(&sblock, cg_blksfree(&acg), d / sblock.fs_frag))
934 			goto goth;
935 	printf("internal error: can't find block in cyl 0\n");
936 	exit(40);
937 goth:
938 	blkno = fragstoblks(&sblock, d);
939 	clrblock(&sblock, cg_blksfree(&acg), blkno);
940 	if (sblock.fs_contigsumsize > 0)
941 		clrbit(cg_clustersfree(&acg), blkno);
942 	acg.cg_cs.cs_nbfree--;
943 	sblock.fs_cstotal.cs_nbfree--;
944 	fscs[0].cs_nbfree--;
945 	if (mode & IFDIR) {
946 		acg.cg_cs.cs_ndir++;
947 		sblock.fs_cstotal.cs_ndir++;
948 		fscs[0].cs_ndir++;
949 	}
950 	if (size != sblock.fs_bsize) {
951 		frag = howmany(size, sblock.fs_fsize);
952 		fscs[0].cs_nffree += sblock.fs_frag - frag;
953 		sblock.fs_cstotal.cs_nffree += sblock.fs_frag - frag;
954 		acg.cg_cs.cs_nffree += sblock.fs_frag - frag;
955 		acg.cg_frsum[sblock.fs_frag - frag]++;
956 		for (i = frag; i < sblock.fs_frag; i++)
957 			setbit(cg_blksfree(&acg), d + i);
958 	}
959 	/* XXX cgwrite(&disk, 0)??? */
960 	wtfs(fsbtodb(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize,
961 	    (char *)&acg);
962 	return ((ufs2_daddr_t)d);
963 }
964 
965 /*
966  * Allocate an inode on the disk
967  */
968 void
969 iput(union dinode *ip, ino_t ino)
970 {
971 	ufs2_daddr_t d;
972 	int c;
973 
974 	c = ino_to_cg(&sblock, ino);
975 	bread(&disk, part_ofs + fsbtodb(&sblock, cgtod(&sblock, 0)), (char *)&acg,
976 	    sblock.fs_cgsize);
977 	if (acg.cg_magic != CG_MAGIC) {
978 		printf("cg 0: bad magic number\n");
979 		exit(31);
980 	}
981 	acg.cg_cs.cs_nifree--;
982 	setbit(cg_inosused(&acg), ino);
983 	wtfs(fsbtodb(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize,
984 	    (char *)&acg);
985 	sblock.fs_cstotal.cs_nifree--;
986 	fscs[0].cs_nifree--;
987 	if (ino >= (unsigned long)sblock.fs_ipg * sblock.fs_ncg) {
988 		printf("fsinit: inode value out of range (%d).\n", ino);
989 		exit(32);
990 	}
991 	d = fsbtodb(&sblock, ino_to_fsba(&sblock, ino));
992 	bread(&disk, part_ofs + d, (char *)iobuf, sblock.fs_bsize);
993 	if (sblock.fs_magic == FS_UFS1_MAGIC)
994 		((struct ufs1_dinode *)iobuf)[ino_to_fsbo(&sblock, ino)] =
995 		    ip->dp1;
996 	else
997 		((struct ufs2_dinode *)iobuf)[ino_to_fsbo(&sblock, ino)] =
998 		    ip->dp2;
999 	wtfs(d, sblock.fs_bsize, (char *)iobuf);
1000 }
1001 
1002 /*
1003  * possibly write to disk
1004  */
1005 static void
1006 wtfs(ufs2_daddr_t bno, int size, char *bf)
1007 {
1008 	if (Nflag)
1009 		return;
1010 	if (bwrite(&disk, part_ofs + bno, bf, size) < 0)
1011 		err(36, "wtfs: %d bytes at sector %jd", size, (intmax_t)bno);
1012 }
1013 
1014 /*
1015  * check if a block is available
1016  */
1017 static int
1018 isblock(struct fs *fs, unsigned char *cp, int h)
1019 {
1020 	unsigned char mask;
1021 
1022 	switch (fs->fs_frag) {
1023 	case 8:
1024 		return (cp[h] == 0xff);
1025 	case 4:
1026 		mask = 0x0f << ((h & 0x1) << 2);
1027 		return ((cp[h >> 1] & mask) == mask);
1028 	case 2:
1029 		mask = 0x03 << ((h & 0x3) << 1);
1030 		return ((cp[h >> 2] & mask) == mask);
1031 	case 1:
1032 		mask = 0x01 << (h & 0x7);
1033 		return ((cp[h >> 3] & mask) == mask);
1034 	default:
1035 		fprintf(stderr, "isblock bad fs_frag %d\n", fs->fs_frag);
1036 		return (0);
1037 	}
1038 }
1039 
1040 /*
1041  * take a block out of the map
1042  */
1043 static void
1044 clrblock(struct fs *fs, unsigned char *cp, int h)
1045 {
1046 	switch ((fs)->fs_frag) {
1047 	case 8:
1048 		cp[h] = 0;
1049 		return;
1050 	case 4:
1051 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
1052 		return;
1053 	case 2:
1054 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
1055 		return;
1056 	case 1:
1057 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
1058 		return;
1059 	default:
1060 		fprintf(stderr, "clrblock bad fs_frag %d\n", fs->fs_frag);
1061 		return;
1062 	}
1063 }
1064 
1065 /*
1066  * put a block into the map
1067  */
1068 static void
1069 setblock(struct fs *fs, unsigned char *cp, int h)
1070 {
1071 	switch (fs->fs_frag) {
1072 	case 8:
1073 		cp[h] = 0xff;
1074 		return;
1075 	case 4:
1076 		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
1077 		return;
1078 	case 2:
1079 		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
1080 		return;
1081 	case 1:
1082 		cp[h >> 3] |= (0x01 << (h & 0x7));
1083 		return;
1084 	default:
1085 		fprintf(stderr, "setblock bad fs_frag %d\n", fs->fs_frag);
1086 		return;
1087 	}
1088 }
1089 
1090 /*
1091  * Determine the number of characters in a
1092  * single line.
1093  */
1094 
1095 static int
1096 charsperline(void)
1097 {
1098 	int columns;
1099 	char *cp;
1100 	struct winsize ws;
1101 
1102 	columns = 0;
1103 	if (ioctl(0, TIOCGWINSZ, &ws) != -1)
1104 		columns = ws.ws_col;
1105 	if (columns == 0 && (cp = getenv("COLUMNS")))
1106 		columns = atoi(cp);
1107 	if (columns == 0)
1108 		columns = 80;	/* last resort */
1109 	return (columns);
1110 }
1111 
1112 static int
1113 ilog2(int val)
1114 {
1115 	u_int n;
1116 
1117 	for (n = 0; n < sizeof(n) * CHAR_BIT; n++)
1118 		if (1 << n == val)
1119 			return (n);
1120 	errx(1, "ilog2: %d is not a power of 2\n", val);
1121 }
1122 
1123 /*
1124  * For the regression test, return predictable random values.
1125  * Otherwise use a true random number generator.
1126  */
1127 static u_int32_t
1128 newfs_random(void)
1129 {
1130 	static int nextnum = 1;
1131 
1132 	if (Rflag)
1133 		return (nextnum++);
1134 	return (arc4random());
1135 }
1136