xref: /freebsd/usr.sbin/makefs/ffs/mkfs.c (revision 3bdf775801b218aa5a89564839405b122f4b233e)
1 /*	$NetBSD: mkfs.c,v 1.20 2004/06/24 22:30:13 lukem Exp $	*/
2 
3 /*
4  * Copyright (c) 2002 Networks Associates Technology, Inc.
5  * All rights reserved.
6  *
7  * This software was developed for the FreeBSD Project by Marshall
8  * Kirk McKusick and Network Associates Laboratories, the Security
9  * Research Division of Network Associates, Inc. under DARPA/SPAWAR
10  * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
11  * research program
12  *
13  * Copyright (c) 1980, 1989, 1993
14  *	The Regents of the University of California.  All rights reserved.
15  *
16  * Redistribution and use in source and binary forms, with or without
17  * modification, are permitted provided that the following conditions
18  * are met:
19  * 1. Redistributions of source code must retain the above copyright
20  *    notice, this list of conditions and the following disclaimer.
21  * 2. Redistributions in binary form must reproduce the above copyright
22  *    notice, this list of conditions and the following disclaimer in the
23  *    documentation and/or other materials provided with the distribution.
24  * 3. Neither the name of the University nor the names of its contributors
25  *    may be used to endorse or promote products derived from this software
26  *    without specific prior written permission.
27  *
28  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38  * SUCH DAMAGE.
39  */
40 
41 #include <sys/cdefs.h>
42 __FBSDID("$FreeBSD$");
43 
44 #include <sys/param.h>
45 #include <sys/time.h>
46 #include <sys/resource.h>
47 
48 #include <stdio.h>
49 #include <stdlib.h>
50 #include <string.h>
51 #include <unistd.h>
52 #include <errno.h>
53 
54 #include "makefs.h"
55 #include "ffs.h"
56 
57 #include <ufs/ufs/dinode.h>
58 #include <ufs/ffs/fs.h>
59 
60 #include "ffs/ufs_bswap.h"
61 #include "ffs/ufs_inode.h"
62 #include "ffs/ffs_extern.h"
63 #include "ffs/newfs_extern.h"
64 
65 #ifndef BBSIZE
66 #define	BBSIZE	8192			/* size of boot area, with label */
67 #endif
68 
69 static void initcg(int, time_t, const fsinfo_t *);
70 static int ilog2(int);
71 
72 static int count_digits(int);
73 
74 /*
75  * make file system for cylinder-group style file systems
76  */
77 #define	UMASK		0755
78 #define	POWEROF2(num)	(((num) & ((num) - 1)) == 0)
79 
80 union {
81 	struct fs fs;
82 	char pad[SBLOCKSIZE];
83 } fsun;
84 #define	sblock	fsun.fs
85 struct	csum *fscs;
86 
87 union {
88 	struct cg cg;
89 	char pad[FFS_MAXBSIZE];
90 } cgun;
91 #define	acg	cgun.cg
92 
93 char *iobuf;
94 int iobufsize;
95 
96 char writebuf[FFS_MAXBSIZE];
97 
98 static int     Oflag;	   /* format as an 4.3BSD file system */
99 static int64_t fssize;	   /* file system size */
100 static int     sectorsize;	   /* bytes/sector */
101 static int     fsize;	   /* fragment size */
102 static int     bsize;	   /* block size */
103 static int     maxbsize;   /* maximum clustering */
104 static int     maxblkspercg;
105 static int     minfree;	   /* free space threshold */
106 static int     opt;		   /* optimization preference (space or time) */
107 static int     density;	   /* number of bytes per inode */
108 static int     maxcontig;	   /* max contiguous blocks to allocate */
109 static int     maxbpg;	   /* maximum blocks per file in a cyl group */
110 static int     bbsize;	   /* boot block size */
111 static int     sbsize;	   /* superblock size */
112 static int     avgfilesize;	   /* expected average file size */
113 static int     avgfpdir;	   /* expected number of files per directory */
114 
115 struct fs *
116 ffs_mkfs(const char *fsys, const fsinfo_t *fsopts)
117 {
118 	int fragsperinode, optimalfpg, origdensity, minfpg, lastminfpg;
119 	int32_t cylno, i, csfrags;
120 	long long sizepb;
121 	void *space;
122 	int size, blks;
123 	int nprintcols, printcolwidth;
124 	ffs_opt_t	*ffs_opts = fsopts->fs_specific;
125 
126 	Oflag =		ffs_opts->version;
127 	fssize =        fsopts->size / fsopts->sectorsize;
128 	sectorsize =    fsopts->sectorsize;
129 	fsize =         ffs_opts->fsize;
130 	bsize =         ffs_opts->bsize;
131 	maxbsize =      ffs_opts->maxbsize;
132 	maxblkspercg =  ffs_opts->maxblkspercg;
133 	minfree =       ffs_opts->minfree;
134 	opt =           ffs_opts->optimization;
135 	density =       ffs_opts->density;
136 	maxcontig =     ffs_opts->maxcontig;
137 	maxbpg =        ffs_opts->maxbpg;
138 	avgfilesize =   ffs_opts->avgfilesize;
139 	avgfpdir =      ffs_opts->avgfpdir;
140 	bbsize =        BBSIZE;
141 	sbsize =        SBLOCKSIZE;
142 
143 	strlcpy(sblock.fs_volname, ffs_opts->label, sizeof(sblock.fs_volname));
144 
145 	if (Oflag == 0) {
146 		sblock.fs_old_inodefmt = FS_42INODEFMT;
147 		sblock.fs_maxsymlinklen = 0;
148 		sblock.fs_old_flags = 0;
149 	} else {
150 		sblock.fs_old_inodefmt = FS_44INODEFMT;
151 		sblock.fs_maxsymlinklen = (Oflag == 1 ? MAXSYMLINKLEN_UFS1 :
152 		    MAXSYMLINKLEN_UFS2);
153 		sblock.fs_old_flags = FS_FLAGS_UPDATED;
154 		sblock.fs_flags = 0;
155 	}
156 	/*
157 	 * Validate the given file system size.
158 	 * Verify that its last block can actually be accessed.
159 	 * Convert to file system fragment sized units.
160 	 */
161 	if (fssize <= 0) {
162 		printf("preposterous size %lld\n", (long long)fssize);
163 		exit(13);
164 	}
165 	ffs_wtfs(fssize - 1, sectorsize, (char *)&sblock, fsopts);
166 
167 	/*
168 	 * collect and verify the filesystem density info
169 	 */
170 	sblock.fs_avgfilesize = avgfilesize;
171 	sblock.fs_avgfpdir = avgfpdir;
172 	if (sblock.fs_avgfilesize <= 0)
173 		printf("illegal expected average file size %d\n",
174 		    sblock.fs_avgfilesize), exit(14);
175 	if (sblock.fs_avgfpdir <= 0)
176 		printf("illegal expected number of files per directory %d\n",
177 		    sblock.fs_avgfpdir), exit(15);
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("fragment size %d is too small, minimum is %d\n",
195 		    sblock.fs_fsize, sectorsize);
196 		exit(18);
197 	}
198 	if (sblock.fs_bsize < MINBSIZE) {
199 		printf("block size %d is too small, minimum is %d\n",
200 		    sblock.fs_bsize, MINBSIZE);
201 		exit(19);
202 	}
203 	if (sblock.fs_bsize > FFS_MAXBSIZE) {
204 		printf("block size %d is too large, maximum is %d\n",
205 		    sblock.fs_bsize, FFS_MAXBSIZE);
206 		exit(19);
207 	}
208 	if (sblock.fs_bsize < sblock.fs_fsize) {
209 		printf("block size (%d) cannot be smaller than fragment size (%d)\n",
210 		    sblock.fs_bsize, sblock.fs_fsize);
211 		exit(20);
212 	}
213 
214 	if (maxbsize < bsize || !POWEROF2(maxbsize)) {
215 		sblock.fs_maxbsize = sblock.fs_bsize;
216 		printf("Extent size set to %d\n", sblock.fs_maxbsize);
217 	} else if (sblock.fs_maxbsize > FS_MAXCONTIG * sblock.fs_bsize) {
218 		sblock.fs_maxbsize = FS_MAXCONTIG * sblock.fs_bsize;
219 		printf("Extent size reduced to %d\n", sblock.fs_maxbsize);
220 	} else {
221 		sblock.fs_maxbsize = maxbsize;
222 	}
223 	sblock.fs_maxcontig = maxcontig;
224 	if (sblock.fs_maxcontig < sblock.fs_maxbsize / sblock.fs_bsize) {
225 		sblock.fs_maxcontig = sblock.fs_maxbsize / sblock.fs_bsize;
226 		printf("Maxcontig raised to %d\n", sblock.fs_maxbsize);
227 	}
228 
229 	if (sblock.fs_maxcontig > 1)
230 		sblock.fs_contigsumsize = MIN(sblock.fs_maxcontig,FS_MAXCONTIG);
231 
232 	sblock.fs_bmask = ~(sblock.fs_bsize - 1);
233 	sblock.fs_fmask = ~(sblock.fs_fsize - 1);
234 	sblock.fs_qbmask = ~sblock.fs_bmask;
235 	sblock.fs_qfmask = ~sblock.fs_fmask;
236 	for (sblock.fs_bshift = 0, i = sblock.fs_bsize; i > 1; i >>= 1)
237 		sblock.fs_bshift++;
238 	for (sblock.fs_fshift = 0, i = sblock.fs_fsize; i > 1; i >>= 1)
239 		sblock.fs_fshift++;
240 	sblock.fs_frag = numfrags(&sblock, sblock.fs_bsize);
241 	for (sblock.fs_fragshift = 0, i = sblock.fs_frag; i > 1; i >>= 1)
242 		sblock.fs_fragshift++;
243 	if (sblock.fs_frag > MAXFRAG) {
244 		printf("fragment size %d is too small, "
245 			"minimum with block size %d is %d\n",
246 		    sblock.fs_fsize, sblock.fs_bsize,
247 		    sblock.fs_bsize / MAXFRAG);
248 		exit(21);
249 	}
250 	sblock.fs_fsbtodb = ilog2(sblock.fs_fsize / sectorsize);
251 	sblock.fs_size = fssize = dbtofsb(&sblock, fssize);
252 
253 	if (Oflag <= 1) {
254 		sblock.fs_magic = FS_UFS1_MAGIC;
255 		sblock.fs_sblockloc = SBLOCK_UFS1;
256 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int32_t);
257 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs1_dinode);
258 		sblock.fs_maxsymlinklen = ((NDADDR + NIADDR) *
259 		    sizeof (int32_t));
260 		sblock.fs_old_inodefmt = FS_44INODEFMT;
261 		sblock.fs_old_cgoffset = 0;
262 		sblock.fs_old_cgmask = 0xffffffff;
263 		sblock.fs_old_size = sblock.fs_size;
264 		sblock.fs_old_rotdelay = 0;
265 		sblock.fs_old_rps = 60;
266 		sblock.fs_old_nspf = sblock.fs_fsize / sectorsize;
267 		sblock.fs_old_cpg = 1;
268 		sblock.fs_old_interleave = 1;
269 		sblock.fs_old_trackskew = 0;
270 		sblock.fs_old_cpc = 0;
271 		sblock.fs_old_postblformat = 1;
272 		sblock.fs_old_nrpos = 1;
273 	} else {
274 		sblock.fs_magic = FS_UFS2_MAGIC;
275 #if 0 /* XXX makefs is used for small filesystems. */
276 		sblock.fs_sblockloc = SBLOCK_UFS2;
277 #else
278 		sblock.fs_sblockloc = SBLOCK_UFS1;
279 #endif
280 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int64_t);
281 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs2_dinode);
282 		sblock.fs_maxsymlinklen = ((NDADDR + NIADDR) *
283 		    sizeof (int64_t));
284 	}
285 
286 	sblock.fs_sblkno =
287 	    roundup(howmany(sblock.fs_sblockloc + SBLOCKSIZE, sblock.fs_fsize),
288 		sblock.fs_frag);
289 	sblock.fs_cblkno = (daddr_t)(sblock.fs_sblkno +
290 	    roundup(howmany(SBLOCKSIZE, sblock.fs_fsize), sblock.fs_frag));
291 	sblock.fs_iblkno = sblock.fs_cblkno + sblock.fs_frag;
292 	sblock.fs_maxfilesize = sblock.fs_bsize * NDADDR - 1;
293 	for (sizepb = sblock.fs_bsize, i = 0; i < NIADDR; i++) {
294 		sizepb *= NINDIR(&sblock);
295 		sblock.fs_maxfilesize += sizepb;
296 	}
297 
298 	/*
299 	 * Calculate the number of blocks to put into each cylinder group.
300 	 *
301 	 * This algorithm selects the number of blocks per cylinder
302 	 * group. The first goal is to have at least enough data blocks
303 	 * in each cylinder group to meet the density requirement. Once
304 	 * this goal is achieved we try to expand to have at least
305 	 * 1 cylinder group. Once this goal is achieved, we pack as
306 	 * many blocks into each cylinder group map as will fit.
307 	 *
308 	 * We start by calculating the smallest number of blocks that we
309 	 * can put into each cylinder group. If this is too big, we reduce
310 	 * the density until it fits.
311 	 */
312 	origdensity = density;
313 	for (;;) {
314 		fragsperinode = MAX(numfrags(&sblock, density), 1);
315 		minfpg = fragsperinode * INOPB(&sblock);
316 		if (minfpg > sblock.fs_size)
317 			minfpg = sblock.fs_size;
318 		sblock.fs_ipg = INOPB(&sblock);
319 		sblock.fs_fpg = roundup(sblock.fs_iblkno +
320 		    sblock.fs_ipg / INOPF(&sblock), sblock.fs_frag);
321 		if (sblock.fs_fpg < minfpg)
322 			sblock.fs_fpg = minfpg;
323 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
324 		    INOPB(&sblock));
325 		sblock.fs_fpg = roundup(sblock.fs_iblkno +
326 		    sblock.fs_ipg / INOPF(&sblock), sblock.fs_frag);
327 		if (sblock.fs_fpg < minfpg)
328 			sblock.fs_fpg = minfpg;
329 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
330 		    INOPB(&sblock));
331 		if (CGSIZE(&sblock) < (unsigned long)sblock.fs_bsize)
332 			break;
333 		density -= sblock.fs_fsize;
334 	}
335 	if (density != origdensity)
336 		printf("density reduced from %d to %d\n", origdensity, density);
337 
338 	if (maxblkspercg <= 0 || maxblkspercg >= fssize)
339 		maxblkspercg = fssize - 1;
340 	/*
341 	 * Start packing more blocks into the cylinder group until
342 	 * it cannot grow any larger, the number of cylinder groups
343 	 * drops below 1, or we reach the size requested.
344 	 */
345 	for ( ; sblock.fs_fpg < maxblkspercg; sblock.fs_fpg += sblock.fs_frag) {
346 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
347 		    INOPB(&sblock));
348 		if (sblock.fs_size / sblock.fs_fpg < 1)
349 			break;
350 		if (CGSIZE(&sblock) < (unsigned long)sblock.fs_bsize)
351 			continue;
352 		if (CGSIZE(&sblock) == (unsigned long)sblock.fs_bsize)
353 			break;
354 		sblock.fs_fpg -= sblock.fs_frag;
355 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
356 		    INOPB(&sblock));
357 		break;
358 	}
359 	/*
360 	 * Check to be sure that the last cylinder group has enough blocks
361 	 * to be viable. If it is too small, reduce the number of blocks
362 	 * per cylinder group which will have the effect of moving more
363 	 * blocks into the last cylinder group.
364 	 */
365 	optimalfpg = sblock.fs_fpg;
366 	for (;;) {
367 		sblock.fs_ncg = howmany(sblock.fs_size, sblock.fs_fpg);
368 		lastminfpg = roundup(sblock.fs_iblkno +
369 		    sblock.fs_ipg / INOPF(&sblock), sblock.fs_frag);
370 		if (sblock.fs_size < lastminfpg) {
371 			printf("Filesystem size %lld < minimum size of %d\n",
372 			    (long long)sblock.fs_size, lastminfpg);
373 			exit(28);
374 		}
375 		if (sblock.fs_size % sblock.fs_fpg >= lastminfpg ||
376 		    sblock.fs_size % sblock.fs_fpg == 0)
377 			break;
378 		sblock.fs_fpg -= sblock.fs_frag;
379 		sblock.fs_ipg = roundup(howmany(sblock.fs_fpg, fragsperinode),
380 		    INOPB(&sblock));
381 	}
382 	if (optimalfpg != sblock.fs_fpg)
383 		printf("Reduced frags per cylinder group from %d to %d %s\n",
384 		   optimalfpg, sblock.fs_fpg, "to enlarge last cyl group");
385 	sblock.fs_cgsize = fragroundup(&sblock, CGSIZE(&sblock));
386 	sblock.fs_dblkno = sblock.fs_iblkno + sblock.fs_ipg / INOPF(&sblock);
387 	if (Oflag <= 1) {
388 		sblock.fs_old_spc = sblock.fs_fpg * sblock.fs_old_nspf;
389 		sblock.fs_old_nsect = sblock.fs_old_spc;
390 		sblock.fs_old_npsect = sblock.fs_old_spc;
391 		sblock.fs_old_ncyl = sblock.fs_ncg;
392 	}
393 
394 	/*
395 	 * fill in remaining fields of the super block
396 	 */
397 	sblock.fs_csaddr = cgdmin(&sblock, 0);
398 	sblock.fs_cssize =
399 	    fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));
400 
401 	/*
402 	 * Setup memory for temporary in-core cylgroup summaries.
403 	 * Cribbed from ffs_mountfs().
404 	 */
405 	size = sblock.fs_cssize;
406 	blks = howmany(size, sblock.fs_fsize);
407 	if (sblock.fs_contigsumsize > 0)
408 		size += sblock.fs_ncg * sizeof(int32_t);
409 	if ((space = (char *)calloc(1, size)) == NULL)
410 		err(1, "memory allocation error for cg summaries");
411 	sblock.fs_csp = space;
412 	space = (char *)space + sblock.fs_cssize;
413 	if (sblock.fs_contigsumsize > 0) {
414 		int32_t *lp;
415 
416 		sblock.fs_maxcluster = lp = space;
417 		for (i = 0; i < sblock.fs_ncg; i++)
418 		*lp++ = sblock.fs_contigsumsize;
419 	}
420 
421 	sblock.fs_sbsize = fragroundup(&sblock, sizeof(struct fs));
422 	if (sblock.fs_sbsize > SBLOCKSIZE)
423 		sblock.fs_sbsize = SBLOCKSIZE;
424 	sblock.fs_minfree = minfree;
425 	sblock.fs_maxcontig = maxcontig;
426 	sblock.fs_maxbpg = maxbpg;
427 	sblock.fs_optim = opt;
428 	sblock.fs_cgrotor = 0;
429 	sblock.fs_pendingblocks = 0;
430 	sblock.fs_pendinginodes = 0;
431 	sblock.fs_cstotal.cs_ndir = 0;
432 	sblock.fs_cstotal.cs_nbfree = 0;
433 	sblock.fs_cstotal.cs_nifree = 0;
434 	sblock.fs_cstotal.cs_nffree = 0;
435 	sblock.fs_fmod = 0;
436 	sblock.fs_ronly = 0;
437 	sblock.fs_state = 0;
438 	sblock.fs_clean = FS_ISCLEAN;
439 	sblock.fs_ronly = 0;
440 	sblock.fs_id[0] = start_time.tv_sec;
441 	sblock.fs_id[1] = random();
442 	sblock.fs_fsmnt[0] = '\0';
443 	csfrags = howmany(sblock.fs_cssize, sblock.fs_fsize);
444 	sblock.fs_dsize = sblock.fs_size - sblock.fs_sblkno -
445 	    sblock.fs_ncg * (sblock.fs_dblkno - sblock.fs_sblkno);
446 	sblock.fs_cstotal.cs_nbfree =
447 	    fragstoblks(&sblock, sblock.fs_dsize) -
448 	    howmany(csfrags, sblock.fs_frag);
449 	sblock.fs_cstotal.cs_nffree =
450 	    fragnum(&sblock, sblock.fs_size) +
451 	    (fragnum(&sblock, csfrags) > 0 ?
452 	    sblock.fs_frag - fragnum(&sblock, csfrags) : 0);
453 	sblock.fs_cstotal.cs_nifree = sblock.fs_ncg * sblock.fs_ipg - ROOTINO;
454 	sblock.fs_cstotal.cs_ndir = 0;
455 	sblock.fs_dsize -= csfrags;
456 	sblock.fs_time = start_time.tv_sec;
457 	if (Oflag <= 1) {
458 		sblock.fs_old_time = start_time.tv_sec;
459 		sblock.fs_old_dsize = sblock.fs_dsize;
460 		sblock.fs_old_csaddr = sblock.fs_csaddr;
461 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
462 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
463 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
464 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
465 	}
466 	/*
467 	 * Dump out summary information about file system.
468 	 */
469 #define	B2MBFACTOR (1 / (1024.0 * 1024.0))
470 	printf("%s: %.1fMB (%lld sectors) block size %d, "
471 	       "fragment size %d\n",
472 	    fsys, (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
473 	    (long long)fsbtodb(&sblock, sblock.fs_size),
474 	    sblock.fs_bsize, sblock.fs_fsize);
475 	printf("\tusing %d cylinder groups of %.2fMB, %d blks, "
476 	       "%d inodes.\n",
477 	    sblock.fs_ncg,
478 	    (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
479 	    sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
480 #undef B2MBFACTOR
481 	/*
482 	 * Now determine how wide each column will be, and calculate how
483 	 * many columns will fit in a 76 char line. 76 is the width of the
484 	 * subwindows in sysinst.
485 	 */
486 	printcolwidth = count_digits(
487 			fsbtodb(&sblock, cgsblock(&sblock, sblock.fs_ncg -1)));
488 	nprintcols = 76 / (printcolwidth + 2);
489 
490 	/*
491 	 * allocate space for superblock, cylinder group map, and
492 	 * two sets of inode blocks.
493 	 */
494 	if (sblock.fs_bsize < SBLOCKSIZE)
495 		iobufsize = SBLOCKSIZE + 3 * sblock.fs_bsize;
496 	else
497 		iobufsize = 4 * sblock.fs_bsize;
498 	if ((iobuf = malloc(iobufsize)) == 0) {
499 		printf("Cannot allocate I/O buffer\n");
500 		exit(38);
501 	}
502 	memset(iobuf, 0, iobufsize);
503 	/*
504 	 * Make a copy of the superblock into the buffer that we will be
505 	 * writing out in each cylinder group.
506 	 */
507 	memcpy(writebuf, &sblock, sbsize);
508 	if (fsopts->needswap)
509 		ffs_sb_swap(&sblock, (struct fs*)writebuf);
510 	memcpy(iobuf, writebuf, SBLOCKSIZE);
511 
512 	printf("super-block backups (for fsck -b #) at:");
513 	for (cylno = 0; cylno < sblock.fs_ncg; cylno++) {
514 		initcg(cylno, start_time.tv_sec, fsopts);
515 		if (cylno % nprintcols == 0)
516 			printf("\n");
517 		printf(" %*lld,", printcolwidth,
518 			(long long)fsbtodb(&sblock, cgsblock(&sblock, cylno)));
519 		fflush(stdout);
520 	}
521 	printf("\n");
522 
523 	/*
524 	 * Now construct the initial file system,
525 	 * then write out the super-block.
526 	 */
527 	sblock.fs_time = start_time.tv_sec;
528 	if (Oflag <= 1) {
529 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
530 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
531 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
532 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
533 	}
534 	if (fsopts->needswap)
535 		sblock.fs_flags |= FS_SWAPPED;
536 	ffs_write_superblock(&sblock, fsopts);
537 	return (&sblock);
538 }
539 
540 /*
541  * Write out the superblock and its duplicates,
542  * and the cylinder group summaries
543  */
544 void
545 ffs_write_superblock(struct fs *fs, const fsinfo_t *fsopts)
546 {
547 	int cylno, size, blks, i, saveflag;
548 	void *space;
549 	char *wrbuf;
550 
551 	saveflag = fs->fs_flags & FS_INTERNAL;
552 	fs->fs_flags &= ~FS_INTERNAL;
553 
554         memcpy(writebuf, &sblock, sbsize);
555 	if (fsopts->needswap)
556 		ffs_sb_swap(fs, (struct fs*)writebuf);
557 	ffs_wtfs(fs->fs_sblockloc / sectorsize, sbsize, writebuf, fsopts);
558 
559 	/* Write out the duplicate super blocks */
560 	for (cylno = 0; cylno < fs->fs_ncg; cylno++)
561 		ffs_wtfs(fsbtodb(fs, cgsblock(fs, cylno)),
562 		    sbsize, writebuf, fsopts);
563 
564 	/* Write out the cylinder group summaries */
565 	size = fs->fs_cssize;
566 	blks = howmany(size, fs->fs_fsize);
567 	space = (void *)fs->fs_csp;
568 	if ((wrbuf = malloc(size)) == NULL)
569 		err(1, "ffs_write_superblock: malloc %d", size);
570 	for (i = 0; i < blks; i+= fs->fs_frag) {
571 		size = fs->fs_bsize;
572 		if (i + fs->fs_frag > blks)
573 			size = (blks - i) * fs->fs_fsize;
574 		if (fsopts->needswap)
575 			ffs_csum_swap((struct csum *)space,
576 			    (struct csum *)wrbuf, size);
577 		else
578 			memcpy(wrbuf, space, (u_int)size);
579 		ffs_wtfs(fsbtodb(fs, fs->fs_csaddr + i), size, wrbuf, fsopts);
580 		space = (char *)space + size;
581 	}
582 	free(wrbuf);
583 	fs->fs_flags |= saveflag;
584 }
585 
586 /*
587  * Initialize a cylinder group.
588  */
589 static void
590 initcg(int cylno, time_t utime, const fsinfo_t *fsopts)
591 {
592 	daddr_t cbase, dmax;
593 	int32_t i, j, d, dlower, dupper, blkno;
594 	struct ufs1_dinode *dp1;
595 	struct ufs2_dinode *dp2;
596 	int start;
597 
598 	/*
599 	 * Determine block bounds for cylinder group.
600 	 * Allow space for super block summary information in first
601 	 * cylinder group.
602 	 */
603 	cbase = cgbase(&sblock, cylno);
604 	dmax = cbase + sblock.fs_fpg;
605 	if (dmax > sblock.fs_size)
606 		dmax = sblock.fs_size;
607 	dlower = cgsblock(&sblock, cylno) - cbase;
608 	dupper = cgdmin(&sblock, cylno) - cbase;
609 	if (cylno == 0)
610 		dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
611 	memset(&acg, 0, sblock.fs_cgsize);
612 	acg.cg_time = utime;
613 	acg.cg_magic = CG_MAGIC;
614 	acg.cg_cgx = cylno;
615 	acg.cg_niblk = sblock.fs_ipg;
616 	acg.cg_initediblk = sblock.fs_ipg < 2 * INOPB(&sblock) ?
617 	    sblock.fs_ipg : 2 * INOPB(&sblock);
618 	acg.cg_ndblk = dmax - cbase;
619 	if (sblock.fs_contigsumsize > 0)
620 		acg.cg_nclusterblks = acg.cg_ndblk >> sblock.fs_fragshift;
621 	start = &acg.cg_space[0] - (u_char *)(&acg.cg_firstfield);
622 	if (Oflag == 2) {
623 		acg.cg_iusedoff = start;
624 	} else {
625 		if (cylno == sblock.fs_ncg - 1)
626 			acg.cg_old_ncyl = howmany(acg.cg_ndblk,
627 			    sblock.fs_fpg / sblock.fs_old_cpg);
628 		else
629 			acg.cg_old_ncyl = sblock.fs_old_cpg;
630 		acg.cg_old_time = acg.cg_time;
631 		acg.cg_time = 0;
632 		acg.cg_old_niblk = acg.cg_niblk;
633 		acg.cg_niblk = 0;
634 		acg.cg_initediblk = 0;
635 		acg.cg_old_btotoff = start;
636 		acg.cg_old_boff = acg.cg_old_btotoff +
637 		    sblock.fs_old_cpg * sizeof(int32_t);
638 		acg.cg_iusedoff = acg.cg_old_boff +
639 		    sblock.fs_old_cpg * sizeof(u_int16_t);
640 	}
641 	acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
642 	if (sblock.fs_contigsumsize <= 0) {
643 		acg.cg_nextfreeoff = acg.cg_freeoff +
644 		   howmany(sblock.fs_fpg, CHAR_BIT);
645 	} else {
646 		acg.cg_clustersumoff = acg.cg_freeoff +
647 		    howmany(sblock.fs_fpg, CHAR_BIT) - sizeof(int32_t);
648 		acg.cg_clustersumoff =
649 		    roundup(acg.cg_clustersumoff, sizeof(int32_t));
650 		acg.cg_clusteroff = acg.cg_clustersumoff +
651 		    (sblock.fs_contigsumsize + 1) * sizeof(int32_t);
652 		acg.cg_nextfreeoff = acg.cg_clusteroff +
653 		    howmany(fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
654 	}
655 	if (acg.cg_nextfreeoff > sblock.fs_cgsize) {
656 		printf("Panic: cylinder group too big\n");
657 		exit(37);
658 	}
659 	acg.cg_cs.cs_nifree += sblock.fs_ipg;
660 	if (cylno == 0)
661 		for (i = 0; i < ROOTINO; i++) {
662 			setbit(cg_inosused_swap(&acg, 0), i);
663 			acg.cg_cs.cs_nifree--;
664 		}
665 	if (cylno > 0) {
666 		/*
667 		 * In cylno 0, beginning space is reserved
668 		 * for boot and super blocks.
669 		 */
670 		for (d = 0, blkno = 0; d < dlower;) {
671 			ffs_setblock(&sblock, cg_blksfree_swap(&acg, 0), blkno);
672 			if (sblock.fs_contigsumsize > 0)
673 				setbit(cg_clustersfree_swap(&acg, 0), blkno);
674 			acg.cg_cs.cs_nbfree++;
675 			d += sblock.fs_frag;
676 			blkno++;
677 		}
678 	}
679 	if ((i = (dupper & (sblock.fs_frag - 1))) != 0) {
680 		acg.cg_frsum[sblock.fs_frag - i]++;
681 		for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
682 			setbit(cg_blksfree_swap(&acg, 0), dupper);
683 			acg.cg_cs.cs_nffree++;
684 		}
685 	}
686 	for (d = dupper, blkno = dupper >> sblock.fs_fragshift;
687 	     d + sblock.fs_frag <= acg.cg_ndblk; ) {
688 		ffs_setblock(&sblock, cg_blksfree_swap(&acg, 0), blkno);
689 		if (sblock.fs_contigsumsize > 0)
690 			setbit(cg_clustersfree_swap(&acg, 0), blkno);
691 		acg.cg_cs.cs_nbfree++;
692 		d += sblock.fs_frag;
693 		blkno++;
694 	}
695 	if (d < acg.cg_ndblk) {
696 		acg.cg_frsum[acg.cg_ndblk - d]++;
697 		for (; d < acg.cg_ndblk; d++) {
698 			setbit(cg_blksfree_swap(&acg, 0), d);
699 			acg.cg_cs.cs_nffree++;
700 		}
701 	}
702 	if (sblock.fs_contigsumsize > 0) {
703 		int32_t *sump = cg_clustersum_swap(&acg, 0);
704 		u_char *mapp = cg_clustersfree_swap(&acg, 0);
705 		int map = *mapp++;
706 		int bit = 1;
707 		int run = 0;
708 
709 		for (i = 0; i < acg.cg_nclusterblks; i++) {
710 			if ((map & bit) != 0) {
711 				run++;
712 			} else if (run != 0) {
713 				if (run > sblock.fs_contigsumsize)
714 					run = sblock.fs_contigsumsize;
715 				sump[run]++;
716 				run = 0;
717 			}
718 			if ((i & (CHAR_BIT - 1)) != (CHAR_BIT - 1)) {
719 				bit <<= 1;
720 			} else {
721 				map = *mapp++;
722 				bit = 1;
723 			}
724 		}
725 		if (run != 0) {
726 			if (run > sblock.fs_contigsumsize)
727 				run = sblock.fs_contigsumsize;
728 			sump[run]++;
729 		}
730 	}
731 	sblock.fs_cs(&sblock, cylno) = acg.cg_cs;
732 	/*
733 	 * Write out the duplicate super block, the cylinder group map
734 	 * and two blocks worth of inodes in a single write.
735 	 */
736 	start = sblock.fs_bsize > SBLOCKSIZE ? sblock.fs_bsize : SBLOCKSIZE;
737 	memcpy(&iobuf[start], &acg, sblock.fs_cgsize);
738 	if (fsopts->needswap)
739 		ffs_cg_swap(&acg, (struct cg*)&iobuf[start], &sblock);
740 	start += sblock.fs_bsize;
741 	dp1 = (struct ufs1_dinode *)(&iobuf[start]);
742 	dp2 = (struct ufs2_dinode *)(&iobuf[start]);
743 	for (i = 0; i < acg.cg_initediblk; i++) {
744 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
745 			/* No need to swap, it'll stay random */
746 			dp1->di_gen = random();
747 			dp1++;
748 		} else {
749 			dp2->di_gen = random();
750 			dp2++;
751 		}
752 	}
753 	ffs_wtfs(fsbtodb(&sblock, cgsblock(&sblock, cylno)), iobufsize, iobuf,
754 	    fsopts);
755 	/*
756 	 * For the old file system, we have to initialize all the inodes.
757 	 */
758 	if (Oflag <= 1) {
759 		for (i = 2 * sblock.fs_frag;
760 		     i < sblock.fs_ipg / INOPF(&sblock);
761 		     i += sblock.fs_frag) {
762 			dp1 = (struct ufs1_dinode *)(&iobuf[start]);
763 			for (j = 0; j < INOPB(&sblock); j++) {
764 				dp1->di_gen = random();
765 				dp1++;
766 			}
767 			ffs_wtfs(fsbtodb(&sblock, cgimin(&sblock, cylno) + i),
768 			    sblock.fs_bsize, &iobuf[start], fsopts);
769 		}
770 	}
771 }
772 
773 /*
774  * read a block from the file system
775  */
776 void
777 ffs_rdfs(daddr_t bno, int size, void *bf, const fsinfo_t *fsopts)
778 {
779 	int n;
780 	off_t offset;
781 
782 	offset = bno;
783 	offset *= fsopts->sectorsize;
784 	if (lseek(fsopts->fd, offset, SEEK_SET) < 0)
785 		err(1, "ffs_rdfs: seek error for sector %lld: %s\n",
786 		    (long long)bno, strerror(errno));
787 	n = read(fsopts->fd, bf, size);
788 	if (n == -1) {
789 		abort();
790 		err(1, "ffs_rdfs: read error bno %lld size %d", (long long)bno,
791 		    size);
792 	}
793 	else if (n != size)
794 		errx(1, "ffs_rdfs: read error for sector %lld: %s\n",
795 		    (long long)bno, strerror(errno));
796 }
797 
798 /*
799  * write a block to the file system
800  */
801 void
802 ffs_wtfs(daddr_t bno, int size, void *bf, const fsinfo_t *fsopts)
803 {
804 	int n;
805 	off_t offset;
806 
807 	offset = bno;
808 	offset *= fsopts->sectorsize;
809 	if (lseek(fsopts->fd, offset, SEEK_SET) < 0)
810 		err(1, "wtfs: seek error for sector %lld: %s\n",
811 		    (long long)bno, strerror(errno));
812 	n = write(fsopts->fd, bf, size);
813 	if (n == -1)
814 		err(1, "wtfs: write error for sector %lld: %s\n",
815 		    (long long)bno, strerror(errno));
816 	else if (n != size)
817 		errx(1, "wtfs: write error for sector %lld: %s\n",
818 		    (long long)bno, strerror(errno));
819 }
820 
821 
822 /* Determine how many digits are needed to print a given integer */
823 static int
824 count_digits(int num)
825 {
826 	int ndig;
827 
828 	for(ndig = 1; num > 9; num /=10, ndig++);
829 
830 	return (ndig);
831 }
832 
833 static int
834 ilog2(int val)
835 {
836 	u_int n;
837 
838 	for (n = 0; n < sizeof(n) * CHAR_BIT; n++)
839 		if (1 << n == val)
840 			return (n);
841 	errx(1, "ilog2: %d is not a power of 2\n", val);
842 }
843