xref: /netbsd-src/sbin/newfs/mkfs.c (revision b757af438b42b93f8c6571f026d8b8ef3eaf5fc9)
1 /*	$NetBSD: mkfs.c,v 1.112 2012/02/13 12:59:56 wiz Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 /*
33  * Copyright (c) 2002 Networks Associates Technology, Inc.
34  * All rights reserved.
35  *
36  * This software was developed for the FreeBSD Project by Marshall
37  * Kirk McKusick and Network Associates Laboratories, the Security
38  * Research Division of Network Associates, Inc. under DARPA/SPAWAR
39  * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
40  * research program
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. All advertising materials mentioning features or use of this software
51  *    must display the following acknowledgement:
52  *	This product includes software developed by the University of
53  *	California, Berkeley and its contributors.
54  * 4. Neither the name of the University nor the names of its contributors
55  *    may be used to endorse or promote products derived from this software
56  *    without specific prior written permission.
57  *
58  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68  * SUCH DAMAGE.
69  */
70 
71 #include <sys/cdefs.h>
72 #ifndef lint
73 #if 0
74 static char sccsid[] = "@(#)mkfs.c	8.11 (Berkeley) 5/3/95";
75 #else
76 __RCSID("$NetBSD: mkfs.c,v 1.112 2012/02/13 12:59:56 wiz Exp $");
77 #endif
78 #endif /* not lint */
79 
80 #include <sys/param.h>
81 #include <sys/mman.h>
82 #include <sys/time.h>
83 #include <sys/resource.h>
84 #include <ufs/ufs/dinode.h>
85 #include <ufs/ufs/dir.h>
86 #include <ufs/ufs/ufs_bswap.h>
87 #include <ufs/ufs/quota2.h>
88 #include <ufs/ffs/fs.h>
89 #include <ufs/ffs/ffs_extern.h>
90 #include <sys/ioctl.h>
91 #include <sys/disklabel.h>
92 
93 #include <err.h>
94 #include <errno.h>
95 #include <string.h>
96 #include <unistd.h>
97 #include <stdlib.h>
98 #include <stddef.h>
99 
100 #ifndef STANDALONE
101 #include <stdio.h>
102 #endif
103 
104 #include "extern.h"
105 
106 union dinode {
107 	struct ufs1_dinode dp1;
108 	struct ufs2_dinode dp2;
109 };
110 
111 static void initcg(int, const struct timeval *);
112 static int fsinit(const struct timeval *, mode_t, uid_t, gid_t);
113 static int makedir(struct direct *, int);
114 static daddr_t alloc(int, int);
115 static void iput(union dinode *, ino_t);
116 static void rdfs(daddr_t, int, void *);
117 static void wtfs(daddr_t, int, void *);
118 static int isblock(struct fs *, unsigned char *, int);
119 static void clrblock(struct fs *, unsigned char *, int);
120 static void setblock(struct fs *, unsigned char *, int);
121 static int ilog2(int);
122 static void zap_old_sblock(int);
123 #ifdef MFS
124 static void calc_memfree(void);
125 static void *mkfs_malloc(size_t size);
126 #endif
127 
128 /*
129  * make file system for cylinder-group style file systems
130  */
131 #define	UMASK		0755
132 
133 union {
134 	struct fs fs;
135 	char pad[SBLOCKSIZE];
136 } fsun;
137 #define	sblock	fsun.fs
138 
139 struct	csum *fscs_0;		/* first block of cylinder summaries */
140 struct	csum *fscs_next;	/* place for next summary */
141 struct	csum *fscs_end;		/* end of summary buffer */
142 struct	csum *fscs_reset;	/* place for next summary after write */
143 uint	fs_csaddr;		/* fragment number to write to */
144 
145 union {
146 	struct cg cg;
147 	char pad[MAXBSIZE];
148 } cgun;
149 #define	acg	cgun.cg
150 
151 #define DIP(dp, field) \
152 	((sblock.fs_magic == FS_UFS1_MAGIC) ? \
153 	(dp)->dp1.di_##field : (dp)->dp2.di_##field)
154 
155 #define EXT2FS_SBOFF	1024	/* XXX: SBOFF in <ufs/ext2fs/ext2fs.h> */
156 
157 char *iobuf;
158 int iobufsize;			/* size to end of 2nd inode block */
159 int iobuf_memsize;		/* Actual buffer size */
160 
161 int	fsi, fso;
162 
163 static void
164 fserr(int num)
165 {
166 #ifdef GARBAGE
167 	extern int Gflag;
168 
169 	if (Gflag)
170 		return;
171 #endif
172 	exit(num);
173 }
174 
175 void
176 mkfs(const char *fsys, int fi, int fo,
177     mode_t mfsmode, uid_t mfsuid, gid_t mfsgid)
178 {
179 	uint fragsperinodeblk, ncg, u;
180 	uint cgzero;
181 	uint64_t inodeblks, cgall;
182 	int32_t cylno, i, csfrags;
183 	int inodes_per_cg;
184 	struct timeval tv;
185 	long long sizepb;
186 	int len, col, delta, fld_width, max_cols;
187 	struct winsize winsize;
188 
189 #ifndef STANDALONE
190 	gettimeofday(&tv, NULL);
191 #endif
192 #ifdef MFS
193 	if (mfs && !Nflag) {
194 		calc_memfree();
195 		if ((uint64_t)fssize * sectorsize > memleft)
196 			fssize = memleft / sectorsize;
197 		if ((membase = mkfs_malloc(fssize * sectorsize)) == NULL)
198 			exit(12);
199 	}
200 #endif
201 	fsi = fi;
202 	fso = fo;
203 	if (Oflag == 0) {
204 		sblock.fs_old_inodefmt = FS_42INODEFMT;
205 		sblock.fs_maxsymlinklen = 0;
206 		sblock.fs_old_flags = 0;
207 	} else {
208 		sblock.fs_old_inodefmt = FS_44INODEFMT;
209 		sblock.fs_maxsymlinklen = (Oflag == 1 ? MAXSYMLINKLEN_UFS1 :
210 		    MAXSYMLINKLEN_UFS2);
211 		sblock.fs_old_flags = FS_FLAGS_UPDATED;
212 		if (isappleufs)
213 			sblock.fs_old_flags = 0;
214 		sblock.fs_flags = 0;
215 	}
216 
217 	/*
218 	 * collect and verify the filesystem density info
219 	 */
220 	sblock.fs_avgfilesize = avgfilesize;
221 	sblock.fs_avgfpdir = avgfpdir;
222 	if (sblock.fs_avgfilesize <= 0) {
223 		printf("illegal expected average file size %d\n",
224 		    sblock.fs_avgfilesize);
225 		fserr(14);
226 	}
227 	if (sblock.fs_avgfpdir <= 0) {
228 		printf("illegal expected number of files per directory %d\n",
229 		    sblock.fs_avgfpdir);
230 		fserr(15);
231 	}
232 	/*
233 	 * collect and verify the block and fragment sizes
234 	 */
235 	sblock.fs_bsize = bsize;
236 	sblock.fs_fsize = fsize;
237 	if (!powerof2(sblock.fs_bsize)) {
238 		printf("block size must be a power of 2, not %d\n",
239 		    sblock.fs_bsize);
240 		fserr(16);
241 	}
242 	if (!powerof2(sblock.fs_fsize)) {
243 		printf("fragment size must be a power of 2, not %d\n",
244 		    sblock.fs_fsize);
245 		fserr(17);
246 	}
247 	if (sblock.fs_fsize < sectorsize) {
248 		printf("fragment size %d is too small, minimum is %d\n",
249 		    sblock.fs_fsize, sectorsize);
250 		fserr(18);
251 	}
252 	if (sblock.fs_bsize < MINBSIZE) {
253 		printf("block size %d is too small, minimum is %d\n",
254 		    sblock.fs_bsize, MINBSIZE);
255 		fserr(19);
256 	}
257 	if (sblock.fs_bsize > MAXBSIZE) {
258 		printf("block size %d is too large, maximum is %d\n",
259 		    sblock.fs_bsize, MAXBSIZE);
260 		fserr(19);
261 	}
262 	if (sblock.fs_bsize < sblock.fs_fsize) {
263 		printf("block size (%d) cannot be smaller than fragment size (%d)\n",
264 		    sblock.fs_bsize, sblock.fs_fsize);
265 		fserr(20);
266 	}
267 
268 	if (maxbsize < bsize || !powerof2(maxbsize)) {
269 		sblock.fs_maxbsize = sblock.fs_bsize;
270 	} else if (sblock.fs_maxbsize > FS_MAXCONTIG * sblock.fs_bsize) {
271 		sblock.fs_maxbsize = FS_MAXCONTIG * sblock.fs_bsize;
272 	} else {
273 		sblock.fs_maxbsize = maxbsize;
274 	}
275 	sblock.fs_maxcontig = maxcontig;
276 	if (sblock.fs_maxcontig < sblock.fs_maxbsize / sblock.fs_bsize) {
277 		sblock.fs_maxcontig = sblock.fs_maxbsize / sblock.fs_bsize;
278 		if (verbosity > 0)
279 			printf("Maxcontig raised to %d\n", sblock.fs_maxbsize);
280 	}
281 	if (sblock.fs_maxcontig > 1)
282 		sblock.fs_contigsumsize = MIN(sblock.fs_maxcontig,FS_MAXCONTIG);
283 
284 	sblock.fs_bmask = ~(sblock.fs_bsize - 1);
285 	sblock.fs_fmask = ~(sblock.fs_fsize - 1);
286 	sblock.fs_qbmask = ~sblock.fs_bmask;
287 	sblock.fs_qfmask = ~sblock.fs_fmask;
288 	for (sblock.fs_bshift = 0, i = sblock.fs_bsize; i > 1; i >>= 1)
289 		sblock.fs_bshift++;
290 	for (sblock.fs_fshift = 0, i = sblock.fs_fsize; i > 1; i >>= 1)
291 		sblock.fs_fshift++;
292 	sblock.fs_frag = numfrags(&sblock, sblock.fs_bsize);
293 	for (sblock.fs_fragshift = 0, i = sblock.fs_frag; i > 1; i >>= 1)
294 		sblock.fs_fragshift++;
295 	if (sblock.fs_frag > MAXFRAG) {
296 		printf("fragment size %d is too small, "
297 			"minimum with block size %d is %d\n",
298 		    sblock.fs_fsize, sblock.fs_bsize,
299 		    sblock.fs_bsize / MAXFRAG);
300 		fserr(21);
301 	}
302 	sblock.fs_fsbtodb = ilog2(sblock.fs_fsize / sectorsize);
303 	sblock.fs_size = dbtofsb(&sblock, fssize);
304 	if (Oflag <= 1) {
305 		if ((uint64_t)sblock.fs_size >= 1ull << 31) {
306 			printf("Too many fragments (0x%" PRIx64
307 			    ") for a FFSv1 filesystem\n", sblock.fs_size);
308 			fserr(22);
309 		}
310 		sblock.fs_magic = FS_UFS1_MAGIC;
311 		sblock.fs_sblockloc = SBLOCK_UFS1;
312 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int32_t);
313 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs1_dinode);
314 		sblock.fs_old_cgoffset = 0;
315 		sblock.fs_old_cgmask = 0xffffffff;
316 		sblock.fs_old_size = sblock.fs_size;
317 		sblock.fs_old_rotdelay = 0;
318 		sblock.fs_old_rps = 60;
319 		sblock.fs_old_nspf = sblock.fs_fsize / sectorsize;
320 		sblock.fs_old_cpg = 1;
321 		sblock.fs_old_interleave = 1;
322 		sblock.fs_old_trackskew = 0;
323 		sblock.fs_old_cpc = 0;
324 		sblock.fs_old_postblformat = FS_DYNAMICPOSTBLFMT;
325 		sblock.fs_old_nrpos = 1;
326 	} else {
327 		sblock.fs_magic = FS_UFS2_MAGIC;
328 		sblock.fs_sblockloc = SBLOCK_UFS2;
329 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int64_t);
330 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs2_dinode);
331 	}
332 
333 	sblock.fs_sblkno =
334 	    roundup(howmany(sblock.fs_sblockloc + SBLOCKSIZE, sblock.fs_fsize),
335 		sblock.fs_frag);
336 	sblock.fs_cblkno = (daddr_t)(sblock.fs_sblkno +
337 	    roundup(howmany(SBLOCKSIZE, sblock.fs_fsize), sblock.fs_frag));
338 	sblock.fs_iblkno = sblock.fs_cblkno + sblock.fs_frag;
339 	sblock.fs_maxfilesize = sblock.fs_bsize * NDADDR - 1;
340 	for (sizepb = sblock.fs_bsize, i = 0; i < NIADDR; i++) {
341 		sizepb *= NINDIR(&sblock);
342 		sblock.fs_maxfilesize += sizepb;
343 	}
344 
345 	/*
346 	 * Calculate the number of blocks to put into each cylinder group.
347 	 *
348 	 * The cylinder group size is limited because the data structure
349 	 * must fit into a single block.
350 	 * We try to have as few cylinder groups as possible, with a proviso
351 	 * that we create at least MINCYLGRPS (==4) except for small
352 	 * filesystems.
353 	 *
354 	 * This algorithm works out how many blocks of inodes would be
355 	 * needed to fill the entire volume at the specified density.
356 	 * It then looks at how big the 'cylinder block' would have to
357 	 * be and, assuming that it is linearly related to the number
358 	 * of inodes and blocks how many cylinder groups are needed to
359 	 * keep the cylinder block below the filesystem block size.
360 	 *
361 	 * The cylinder groups are then all created with the average size.
362 	 *
363 	 * Space taken by the red tape on cylinder groups other than the
364 	 * first is ignored.
365 	 */
366 
367 	/* There must be space for 1 inode block and 2 data blocks */
368 	if (sblock.fs_size < sblock.fs_iblkno + 3 * sblock.fs_frag) {
369 		printf("Filesystem size %lld < minimum size of %d\n",
370 		    (long long)sblock.fs_size, sblock.fs_iblkno + 3 * sblock.fs_frag);
371 		fserr(23);
372 	}
373 	if (num_inodes != 0)
374 		inodeblks = howmany(num_inodes, INOPB(&sblock));
375 	else {
376 		/*
377 		 * Calculate 'per inode block' so we can allocate less than
378 		 * 1 fragment per inode - useful for /dev.
379 		 */
380 		fragsperinodeblk = MAX(numfrags(&sblock,
381 					(uint64_t)density * INOPB(&sblock)), 1);
382 		inodeblks = (sblock.fs_size - sblock.fs_iblkno) /
383 			(sblock.fs_frag + fragsperinodeblk);
384 	}
385 	if (inodeblks == 0)
386 		inodeblks = 1;
387 	/* Ensure that there are at least 2 data blocks (or we fail below) */
388 	if (inodeblks > (uint64_t)(sblock.fs_size - sblock.fs_iblkno)/sblock.fs_frag - 2)
389 		inodeblks = (sblock.fs_size-sblock.fs_iblkno)/sblock.fs_frag-2;
390 	/* Even UFS2 limits number of inodes to 2^31 (fs_ipg is int32_t) */
391 	if (inodeblks * INOPB(&sblock) >= 1ull << 31)
392 		inodeblks = ((1ull << 31) - NBBY) / INOPB(&sblock);
393 	/*
394 	 * See what would happen if we tried to use 1 cylinder group.
395 	 * Assume space linear, so work out number of cylinder groups needed.
396 	 */
397 	cgzero = CGSIZE_IF(&sblock, 0, 0);
398 	cgall = CGSIZE_IF(&sblock, inodeblks * INOPB(&sblock), sblock.fs_size);
399 	ncg = howmany(cgall - cgzero, sblock.fs_bsize - cgzero);
400 	if (ncg < MINCYLGRPS) {
401 		/*
402 		 * We would like to allocate MINCLYGRPS cylinder groups,
403 		 * but for small file sytems (especially ones with a lot
404 		 * of inodes) this is not desirable (or possible).
405 		 */
406 		u = sblock.fs_size / 2 / (sblock.fs_iblkno +
407 						inodeblks * sblock.fs_frag);
408 		if (u > ncg)
409 			ncg = u;
410 		if (ncg > MINCYLGRPS)
411 			ncg = MINCYLGRPS;
412 		if (ncg > inodeblks)
413 			ncg = inodeblks;
414 	}
415 	/*
416 	 * Put an equal number of blocks in each cylinder group.
417 	 * Round up so we don't have more fragments in the last CG than
418 	 * the earlier ones (does that matter?), but kill a block if the
419 	 * CGSIZE becomes too big (only happens if there are a lot of CGs).
420 	 */
421 	sblock.fs_fpg = roundup(howmany(sblock.fs_size, ncg), sblock.fs_frag);
422 	/* Round up the fragments/group so the bitmap bytes are full */
423 	sblock.fs_fpg = roundup(sblock.fs_fpg, NBBY);
424 	inodes_per_cg = ((inodeblks - 1) / ncg + 1) * INOPB(&sblock);
425 
426 	i = CGSIZE_IF(&sblock, inodes_per_cg, sblock.fs_fpg);
427 	if (i > sblock.fs_bsize) {
428 		sblock.fs_fpg -= (i - sblock.fs_bsize) * NBBY;
429 		/* ... and recalculate how many cylinder groups we now need */
430 		ncg = howmany(sblock.fs_size, sblock.fs_fpg);
431 		inodes_per_cg = ((inodeblks - 1) / ncg + 1) * INOPB(&sblock);
432 	}
433 	sblock.fs_ipg = inodes_per_cg;
434 	/* Sanity check on our sums... */
435 	if ((int)CGSIZE(&sblock) > sblock.fs_bsize) {
436 		printf("CGSIZE miscalculated %d > %d\n",
437 		    (int)CGSIZE(&sblock), sblock.fs_bsize);
438 		fserr(24);
439 	}
440 
441 	sblock.fs_dblkno = sblock.fs_iblkno + sblock.fs_ipg / INOPF(&sblock);
442 	/* Check that the last cylinder group has enough space for the inodes */
443 	i = sblock.fs_size - sblock.fs_fpg * (ncg - 1ull);
444 	if (i < sblock.fs_dblkno) {
445 		/*
446 		 * Since we make all the cylinder groups the same size, the
447 		 * last will only be small if there are a large number of
448 		 * cylinder groups. If we pull even a fragment from each
449 		 * of the other groups then the last CG will be overfull.
450 		 * So we just kill the last CG.
451 		 */
452 		ncg--;
453 		sblock.fs_size -= i;
454 	}
455 	sblock.fs_ncg = ncg;
456 
457 	sblock.fs_cgsize = fragroundup(&sblock, CGSIZE(&sblock));
458 	if (Oflag <= 1) {
459 		sblock.fs_old_spc = sblock.fs_fpg * sblock.fs_old_nspf;
460 		sblock.fs_old_nsect = sblock.fs_old_spc;
461 		sblock.fs_old_npsect = sblock.fs_old_spc;
462 		sblock.fs_old_ncyl = sblock.fs_ncg;
463 	}
464 
465 	/*
466 	 * Cylinder group summary information for each cylinder is written
467 	 * into the first cylinder group.
468 	 * Write this fragment by fragment, but doing the first CG last
469 	 * (after we've taken stuff off for the structure itself and the
470 	 * root directory.
471 	 */
472 	sblock.fs_csaddr = cgdmin(&sblock, 0);
473 	sblock.fs_cssize =
474 	    fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));
475 	if (512 % sizeof *fscs_0)
476 		errx(1, "cylinder group summary doesn't fit in sectors");
477 	fscs_0 = mmap(0, 2 * sblock.fs_fsize, PROT_READ|PROT_WRITE,
478 			MAP_ANON|MAP_PRIVATE, -1, 0);
479 	if (fscs_0 == MAP_FAILED)
480 		exit(39);
481 	memset(fscs_0, 0, 2 * sblock.fs_fsize);
482 	fs_csaddr = sblock.fs_csaddr;
483 	fscs_next = fscs_0;
484 	fscs_end = (void *)((char *)fscs_0 + 2 * sblock.fs_fsize);
485 	fscs_reset = (void *)((char *)fscs_0 + sblock.fs_fsize);
486 	/*
487 	 * fill in remaining fields of the super block
488 	 */
489 	sblock.fs_sbsize = fragroundup(&sblock, sizeof(struct fs));
490 	if (sblock.fs_sbsize > SBLOCKSIZE)
491 		sblock.fs_sbsize = SBLOCKSIZE;
492 	sblock.fs_minfree = minfree;
493 	sblock.fs_maxcontig = maxcontig;
494 	sblock.fs_maxbpg = maxbpg;
495 	sblock.fs_optim = opt;
496 	sblock.fs_cgrotor = 0;
497 	sblock.fs_pendingblocks = 0;
498 	sblock.fs_pendinginodes = 0;
499 	sblock.fs_cstotal.cs_ndir = 0;
500 	sblock.fs_cstotal.cs_nbfree = 0;
501 	sblock.fs_cstotal.cs_nifree = 0;
502 	sblock.fs_cstotal.cs_nffree = 0;
503 	sblock.fs_fmod = 0;
504 	sblock.fs_ronly = 0;
505 	sblock.fs_state = 0;
506 	sblock.fs_clean = FS_ISCLEAN;
507 	sblock.fs_ronly = 0;
508 	sblock.fs_id[0] = (long)tv.tv_sec;	/* XXXfvdl huh? */
509 	sblock.fs_id[1] = arc4random() & INT32_MAX;
510 	sblock.fs_fsmnt[0] = '\0';
511 	csfrags = howmany(sblock.fs_cssize, sblock.fs_fsize);
512 	sblock.fs_dsize = sblock.fs_size - sblock.fs_sblkno -
513 	    sblock.fs_ncg * (sblock.fs_dblkno - sblock.fs_sblkno);
514 	sblock.fs_cstotal.cs_nbfree =
515 	    fragstoblks(&sblock, sblock.fs_dsize) -
516 	    howmany(csfrags, sblock.fs_frag);
517 	sblock.fs_cstotal.cs_nffree =
518 	    fragnum(&sblock, sblock.fs_size) +
519 	    (fragnum(&sblock, csfrags) > 0 ?
520 	    sblock.fs_frag - fragnum(&sblock, csfrags) : 0);
521 	sblock.fs_cstotal.cs_nifree = sblock.fs_ncg * sblock.fs_ipg - ROOTINO;
522 	sblock.fs_cstotal.cs_ndir = 0;
523 	sblock.fs_dsize -= csfrags;
524 	sblock.fs_time = tv.tv_sec;
525 	if (Oflag <= 1) {
526 		sblock.fs_old_time = tv.tv_sec;
527 		sblock.fs_old_dsize = sblock.fs_dsize;
528 		sblock.fs_old_csaddr = sblock.fs_csaddr;
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 	/* add quota data in superblock */
535 	if (quotas) {
536 		sblock.fs_flags |= FS_DOQUOTA2;
537 		sblock.fs_quota_magic = Q2_HEAD_MAGIC;
538 		sblock.fs_quota_flags = quotas;
539 	}
540 	/*
541 	 * Dump out summary information about file system.
542 	 */
543 	if (verbosity > 0) {
544 #define	B2MBFACTOR (1 / (1024.0 * 1024.0))
545 		printf("%s: %.1fMB (%lld sectors) block size %d, "
546 		       "fragment size %d\n",
547 		    fsys, (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
548 		    (long long)fsbtodb(&sblock, sblock.fs_size),
549 		    sblock.fs_bsize, sblock.fs_fsize);
550 		printf("\tusing %d cylinder groups of %.2fMB, %d blks, "
551 		       "%d inodes.\n",
552 		    sblock.fs_ncg,
553 		    (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
554 		    sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
555 #undef B2MBFACTOR
556 	}
557 
558 	/*
559 	 * allocate space for superblock, cylinder group map, and
560 	 * two sets of inode blocks.
561 	 */
562 	if (sblock.fs_bsize < SBLOCKSIZE)
563 		iobufsize = SBLOCKSIZE + 3 * sblock.fs_bsize;
564 	else
565 		iobufsize = 4 * sblock.fs_bsize;
566 	iobuf_memsize = iobufsize;
567 	if (!mfs && sblock.fs_magic == FS_UFS1_MAGIC) {
568 		/* A larger buffer so we can write multiple inode blks */
569 		iobuf_memsize += 14 * sblock.fs_bsize;
570 	}
571 	for (;;) {
572 		iobuf = mmap(0, iobuf_memsize, PROT_READ|PROT_WRITE,
573 				MAP_ANON|MAP_PRIVATE, -1, 0);
574 		if (iobuf != MAP_FAILED)
575 			break;
576 		if (iobuf_memsize != iobufsize) {
577 			/* Try again with the smaller size */
578 			iobuf_memsize = iobufsize;
579 			continue;
580 		}
581 		printf("Cannot allocate I/O buffer\n");
582 		exit(38);
583 	}
584 	memset(iobuf, 0, iobuf_memsize);
585 
586 	/*
587 	 * We now start writing to the filesystem
588 	 */
589 
590 	if (!Nflag) {
591 		/*
592 		 * Validate the given file system size.
593 		 * Verify that its last block can actually be accessed.
594 		 * Convert to file system fragment sized units.
595 		 */
596 		if (fssize <= 0) {
597 			printf("preposterous size %lld\n", (long long)fssize);
598 			fserr(13);
599 		}
600 		wtfs(fssize - 1, sectorsize, iobuf);
601 
602 		/*
603 		 * Ensure there is nothing that looks like a filesystem
604 		 * superbock anywhere other than where ours will be.
605 		 * If fsck finds the wrong one all hell breaks loose!
606 		 */
607 		for (i = 0; ; i++) {
608 			static const int sblocklist[] = SBLOCKSEARCH;
609 			int sblkoff = sblocklist[i];
610 			int sz;
611 			if (sblkoff == -1)
612 				break;
613 			/* Remove main superblock */
614 			zap_old_sblock(sblkoff);
615 			/* and all possible locations for the first alternate */
616 			sblkoff += SBLOCKSIZE;
617 			for (sz = SBLOCKSIZE; sz <= 0x10000; sz <<= 1)
618 				zap_old_sblock(roundup(sblkoff, sz));
619 		}
620 		/*
621 		 * Also zap possible Ext2fs magic leftover to prevent
622 		 * kernel vfs_mountroot() and bootloaders from mis-recognizing
623 		 * this file system as Ext2fs.
624 		 */
625 		zap_old_sblock(EXT2FS_SBOFF);
626 
627 		if (isappleufs) {
628 			struct appleufslabel appleufs;
629 			ffs_appleufs_set(&appleufs, appleufs_volname,
630 			    tv.tv_sec, 0);
631 			wtfs(APPLEUFS_LABEL_OFFSET/sectorsize,
632 			    APPLEUFS_LABEL_SIZE, &appleufs);
633 		} else if (APPLEUFS_LABEL_SIZE % sectorsize == 0) {
634 			struct appleufslabel appleufs;
635 			/* Look for & zap any existing valid apple ufs labels */
636 			rdfs(APPLEUFS_LABEL_OFFSET/sectorsize,
637 			    APPLEUFS_LABEL_SIZE, &appleufs);
638 			if (ffs_appleufs_validate(fsys, &appleufs, NULL) == 0) {
639 				memset(&appleufs, 0, sizeof(appleufs));
640 				wtfs(APPLEUFS_LABEL_OFFSET/sectorsize,
641 				    APPLEUFS_LABEL_SIZE, &appleufs);
642 			}
643 		}
644 	}
645 
646 	/*
647 	 * Make a copy of the superblock into the buffer that we will be
648 	 * writing out in each cylinder group.
649 	 */
650 	memcpy(iobuf, &sblock, sizeof sblock);
651 	if (needswap)
652 		ffs_sb_swap(&sblock, (struct fs *)iobuf);
653 	if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0)
654 		memset(iobuf + offsetof(struct fs, fs_old_postbl_start),
655 		    0xff, 256);
656 
657 	if (verbosity >= 3)
658 		printf("super-block backups (for fsck_ffs -b #) at:\n");
659 	/* If we are printing more than one line of numbers, line up columns */
660 	fld_width = verbosity < 4 ? 1 : snprintf(NULL, 0, "%" PRIu64,
661 		(uint64_t)fsbtodb(&sblock, cgsblock(&sblock, sblock.fs_ncg-1)));
662 	/* Get terminal width */
663 	if (ioctl(fileno(stdout), TIOCGWINSZ, &winsize) == 0)
664 		max_cols = winsize.ws_col;
665 	else
666 		max_cols = 80;
667 	if (Nflag && verbosity == 3)
668 		/* Leave space to add " ..." after one row of numbers */
669 		max_cols -= 4;
670 #define BASE 0x10000	/* For some fixed-point maths */
671 	col = 0;
672 	delta = verbosity > 2 ? 0 : max_cols * BASE / sblock.fs_ncg;
673 	for (cylno = 0; cylno < sblock.fs_ncg; cylno++) {
674 		fflush(stdout);
675 		initcg(cylno, &tv);
676 		if (verbosity < 2)
677 			continue;
678 		if (delta > 0) {
679 			if (Nflag)
680 				/* No point doing dots for -N */
681 				break;
682 			/* Print dots scaled to end near RH margin */
683 			for (col += delta; col > BASE; col -= BASE)
684 				printf(".");
685 			continue;
686 		}
687 		/* Print superblock numbers */
688 		len = printf("%s%*" PRIu64 ",", col ? " " : "", fld_width,
689 		    (uint64_t)fsbtodb(&sblock, cgsblock(&sblock, cylno)));
690 		col += len;
691 		if (col + len < max_cols)
692 			/* Next number fits */
693 			continue;
694 		/* Next number won't fit, need a newline */
695 		if (verbosity <= 3) {
696 			/* Print dots for subsequent cylinder groups */
697 			delta = sblock.fs_ncg - cylno - 1;
698 			if (delta != 0) {
699 				if (Nflag) {
700 					printf(" ...");
701 					break;
702 				}
703 				delta = max_cols * BASE / delta;
704 			}
705 		}
706 		col = 0;
707 		printf("\n");
708 	}
709 #undef BASE
710 	if (col > 0)
711 		printf("\n");
712 	if (Nflag)
713 		exit(0);
714 
715 	/*
716 	 * Now construct the initial file system,
717 	 */
718 	if (fsinit(&tv, mfsmode, mfsuid, mfsgid) == 0 && mfs)
719 		errx(1, "Error making filesystem");
720 	sblock.fs_time = tv.tv_sec;
721 	if (Oflag <= 1) {
722 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
723 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
724 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
725 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
726 	}
727 	/*
728 	 * Write out the super-block and zeros until the first cg info
729 	 */
730 	i = cgsblock(&sblock, 0) * sblock.fs_fsize - sblock.fs_sblockloc,
731 	memset(iobuf, 0, i);
732 	memcpy(iobuf, &sblock, sizeof sblock);
733 	if (needswap)
734 		ffs_sb_swap(&sblock, (struct fs *)iobuf);
735 	if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0)
736 		memset(iobuf + offsetof(struct fs, fs_old_postbl_start),
737 		    0xff, 256);
738 	wtfs(sblock.fs_sblockloc / sectorsize, i, iobuf);
739 
740 	/* Write out first and last cylinder summary sectors */
741 	if (needswap)
742 		ffs_csum_swap(fscs_0, fscs_0, sblock.fs_fsize);
743 	wtfs(fsbtodb(&sblock, sblock.fs_csaddr), sblock.fs_fsize, fscs_0);
744 
745 	if (fscs_next > fscs_reset) {
746 		if (needswap)
747 			ffs_csum_swap(fscs_reset, fscs_reset, sblock.fs_fsize);
748 		fs_csaddr++;
749 		wtfs(fsbtodb(&sblock, fs_csaddr), sblock.fs_fsize, fscs_reset);
750 	}
751 
752 	/* mfs doesn't need these permanently allocated */
753 	munmap(iobuf, iobuf_memsize);
754 	munmap(fscs_0, 2 * sblock.fs_fsize);
755 }
756 
757 /*
758  * Initialize a cylinder group.
759  */
760 void
761 initcg(int cylno, const struct timeval *tv)
762 {
763 	daddr_t cbase, dmax;
764 	int32_t i, d, dlower, dupper, blkno;
765 	uint32_t u;
766 	struct ufs1_dinode *dp1;
767 	struct ufs2_dinode *dp2;
768 	int start;
769 
770 	/*
771 	 * Determine block bounds for cylinder group.
772 	 * Allow space for super block summary information in first
773 	 * cylinder group.
774 	 */
775 	cbase = cgbase(&sblock, cylno);
776 	dmax = cbase + sblock.fs_fpg;
777 	if (dmax > sblock.fs_size)
778 		dmax = sblock.fs_size;
779 	dlower = cgsblock(&sblock, cylno) - cbase;
780 	dupper = cgdmin(&sblock, cylno) - cbase;
781 	if (cylno == 0) {
782 		dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
783 		if (dupper >= cgstart(&sblock, cylno + 1)) {
784 			printf("\rToo many cylinder groups to fit summary "
785 				"information into first cylinder group\n");
786 			fserr(40);
787 		}
788 	}
789 	memset(&acg, 0, sblock.fs_cgsize);
790 	acg.cg_magic = CG_MAGIC;
791 	acg.cg_cgx = cylno;
792 	acg.cg_ndblk = dmax - cbase;
793 	if (sblock.fs_contigsumsize > 0)
794 		acg.cg_nclusterblks = acg.cg_ndblk >> sblock.fs_fragshift;
795 	start = &acg.cg_space[0] - (u_char *)(&acg.cg_firstfield);
796 	if (Oflag == 2) {
797 		acg.cg_time = tv->tv_sec;
798 		acg.cg_niblk = sblock.fs_ipg;
799 		acg.cg_initediblk = sblock.fs_ipg < 2 * INOPB(&sblock) ?
800 		    sblock.fs_ipg : 2 * INOPB(&sblock);
801 		acg.cg_iusedoff = start;
802 	} else {
803 		acg.cg_old_ncyl = sblock.fs_old_cpg;
804 		if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0 &&
805 		    (cylno == sblock.fs_ncg - 1))
806 			acg.cg_old_ncyl =
807 			    sblock.fs_old_ncyl % sblock.fs_old_cpg;
808 		acg.cg_old_time = tv->tv_sec;
809 		acg.cg_old_niblk = sblock.fs_ipg;
810 		acg.cg_old_btotoff = start;
811 		acg.cg_old_boff = acg.cg_old_btotoff +
812 		    sblock.fs_old_cpg * sizeof(int32_t);
813 		acg.cg_iusedoff = acg.cg_old_boff +
814 		    sblock.fs_old_cpg * sizeof(u_int16_t);
815 	}
816 	acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
817 	if (sblock.fs_contigsumsize <= 0) {
818 		acg.cg_nextfreeoff = acg.cg_freeoff +
819 		   howmany(sblock.fs_fpg, CHAR_BIT);
820 	} else {
821 		acg.cg_clustersumoff = acg.cg_freeoff +
822 		    howmany(sblock.fs_fpg, CHAR_BIT) - sizeof(int32_t);
823 		if (isappleufs) {
824 			/* Apple PR2216969 gives rationale for this change.
825 			 * I believe they were mistaken, but we need to
826 			 * duplicate it for compatibility.  -- dbj@NetBSD.org
827 			 */
828 			acg.cg_clustersumoff += sizeof(int32_t);
829 		}
830 		acg.cg_clustersumoff =
831 		    roundup(acg.cg_clustersumoff, sizeof(int32_t));
832 		acg.cg_clusteroff = acg.cg_clustersumoff +
833 		    (sblock.fs_contigsumsize + 1) * sizeof(int32_t);
834 		acg.cg_nextfreeoff = acg.cg_clusteroff +
835 		    howmany(fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
836 	}
837 	if (acg.cg_nextfreeoff > sblock.fs_cgsize) {
838 		printf("Panic: cylinder group too big\n");
839 		fserr(37);
840 	}
841 	acg.cg_cs.cs_nifree += sblock.fs_ipg;
842 	if (cylno == 0)
843 		for (u = 0; u < ROOTINO; u++) {
844 			setbit(cg_inosused(&acg, 0), u);
845 			acg.cg_cs.cs_nifree--;
846 		}
847 	if (cylno > 0) {
848 		/*
849 		 * In cylno 0, beginning space is reserved
850 		 * for boot and super blocks.
851 		 */
852 		for (d = 0, blkno = 0; d < dlower;) {
853 			setblock(&sblock, cg_blksfree(&acg, 0), blkno);
854 			if (sblock.fs_contigsumsize > 0)
855 				setbit(cg_clustersfree(&acg, 0), blkno);
856 			acg.cg_cs.cs_nbfree++;
857 			if (Oflag <= 1) {
858 				int cn = old_cbtocylno(&sblock, d);
859 				old_cg_blktot(&acg, 0)[cn]++;
860 				old_cg_blks(&sblock, &acg,
861 				    cn, 0)[old_cbtorpos(&sblock, d)]++;
862 			}
863 			d += sblock.fs_frag;
864 			blkno++;
865 		}
866 	}
867 	if ((i = (dupper & (sblock.fs_frag - 1))) != 0) {
868 		acg.cg_frsum[sblock.fs_frag - i]++;
869 		for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
870 			setbit(cg_blksfree(&acg, 0), dupper);
871 			acg.cg_cs.cs_nffree++;
872 		}
873 	}
874 	for (d = dupper, blkno = dupper >> sblock.fs_fragshift;
875 	     d + sblock.fs_frag <= acg.cg_ndblk; ) {
876 		setblock(&sblock, cg_blksfree(&acg, 0), blkno);
877 		if (sblock.fs_contigsumsize > 0)
878 			setbit(cg_clustersfree(&acg, 0), blkno);
879 		acg.cg_cs.cs_nbfree++;
880 		if (Oflag <= 1) {
881 			int cn = old_cbtocylno(&sblock, d);
882 			old_cg_blktot(&acg, 0)[cn]++;
883 			old_cg_blks(&sblock, &acg,
884 			    cn, 0)[old_cbtorpos(&sblock, d)]++;
885 		}
886 		d += sblock.fs_frag;
887 		blkno++;
888 	}
889 	if (d < acg.cg_ndblk) {
890 		acg.cg_frsum[acg.cg_ndblk - d]++;
891 		for (; d < acg.cg_ndblk; d++) {
892 			setbit(cg_blksfree(&acg, 0), d);
893 			acg.cg_cs.cs_nffree++;
894 		}
895 	}
896 	if (sblock.fs_contigsumsize > 0) {
897 		int32_t *sump = cg_clustersum(&acg, 0);
898 		u_char *mapp = cg_clustersfree(&acg, 0);
899 		int map = *mapp++;
900 		int bit = 1;
901 		int run = 0;
902 
903 		for (i = 0; i < acg.cg_nclusterblks; i++) {
904 			if ((map & bit) != 0) {
905 				run++;
906 			} else if (run != 0) {
907 				if (run > sblock.fs_contigsumsize)
908 					run = sblock.fs_contigsumsize;
909 				sump[run]++;
910 				run = 0;
911 			}
912 			if ((i & (CHAR_BIT - 1)) != (CHAR_BIT - 1)) {
913 				bit <<= 1;
914 			} else {
915 				map = *mapp++;
916 				bit = 1;
917 			}
918 		}
919 		if (run != 0) {
920 			if (run > sblock.fs_contigsumsize)
921 				run = sblock.fs_contigsumsize;
922 			sump[run]++;
923 		}
924 	}
925 	*fscs_next++ = acg.cg_cs;
926 	if (fscs_next == fscs_end) {
927 		/* write block of cylinder group summary info into cyl 0 */
928 		if (needswap)
929 			ffs_csum_swap(fscs_reset, fscs_reset, sblock.fs_fsize);
930 		fs_csaddr++;
931 		wtfs(fsbtodb(&sblock, fs_csaddr), sblock.fs_fsize, fscs_reset);
932 		fscs_next = fscs_reset;
933 		memset(fscs_next, 0, sblock.fs_fsize);
934 	}
935 	/*
936 	 * Write out the duplicate super block, the cylinder group map
937 	 * and two blocks worth of inodes in a single write.
938 	 */
939 	start = sblock.fs_bsize > SBLOCKSIZE ? sblock.fs_bsize : SBLOCKSIZE;
940 	memcpy(&iobuf[start], &acg, sblock.fs_cgsize);
941 	if (needswap)
942 		ffs_cg_swap(&acg, (struct cg*)&iobuf[start], &sblock);
943 	start += sblock.fs_bsize;
944 	dp1 = (struct ufs1_dinode *)(&iobuf[start]);
945 	dp2 = (struct ufs2_dinode *)(&iobuf[start]);
946 	for (i = MIN(sblock.fs_ipg, 2) * INOPB(&sblock); i != 0; i--) {
947 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
948 			/* No need to swap, it'll stay random */
949 			dp1->di_gen = arc4random() & INT32_MAX;
950 			dp1++;
951 		} else {
952 			dp2->di_gen = arc4random() & INT32_MAX;
953 			dp2++;
954 		}
955 	}
956 	wtfs(fsbtodb(&sblock, cgsblock(&sblock, cylno)), iobufsize, iobuf);
957 	/*
958 	 * For the old file system, we have to initialize all the inodes.
959 	 */
960 	if (sblock.fs_magic != FS_UFS1_MAGIC)
961 		return;
962 
963 	/* Write 'd' (usually 16 * fs_frag) file-system fragments at once */
964 	d = (iobuf_memsize - start) / sblock.fs_bsize * sblock.fs_frag;
965 	dupper = sblock.fs_ipg / INOPF(&sblock);
966 	for (i = 2 * sblock.fs_frag; i < dupper; i += d) {
967 		if (d > dupper - i)
968 			d = dupper - i;
969 		dp1 = (struct ufs1_dinode *)(&iobuf[start]);
970 		do
971 			dp1->di_gen = arc4random() & INT32_MAX;
972 		while ((char *)++dp1 < &iobuf[iobuf_memsize]);
973 		wtfs(fsbtodb(&sblock, cgimin(&sblock, cylno) + i),
974 		    d * sblock.fs_bsize / sblock.fs_frag, &iobuf[start]);
975 	}
976 }
977 
978 /*
979  * initialize the file system
980  */
981 
982 #ifdef LOSTDIR
983 #define	PREDEFDIR 3
984 #else
985 #define	PREDEFDIR 2
986 #endif
987 
988 struct direct root_dir[] = {
989 	{ ROOTINO, sizeof(struct direct), DT_DIR, 1, "." },
990 	{ ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
991 #ifdef LOSTDIR
992 	{ LOSTFOUNDINO, sizeof(struct direct), DT_DIR, 10, "lost+found" },
993 #endif
994 };
995 struct odirect {
996 	u_int32_t d_ino;
997 	u_int16_t d_reclen;
998 	u_int16_t d_namlen;
999 	u_char	d_name[FFS_MAXNAMLEN + 1];
1000 } oroot_dir[] = {
1001 	{ ROOTINO, sizeof(struct direct), 1, "." },
1002 	{ ROOTINO, sizeof(struct direct), 2, ".." },
1003 #ifdef LOSTDIR
1004 	{ LOSTFOUNDINO, sizeof(struct direct), 10, "lost+found" },
1005 #endif
1006 };
1007 #ifdef LOSTDIR
1008 struct direct lost_found_dir[] = {
1009 	{ LOSTFOUNDINO, sizeof(struct direct), DT_DIR, 1, "." },
1010 	{ ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
1011 	{ 0, DIRBLKSIZ, 0, 0, 0 },
1012 };
1013 struct odirect olost_found_dir[] = {
1014 	{ LOSTFOUNDINO, sizeof(struct direct), 1, "." },
1015 	{ ROOTINO, sizeof(struct direct), 2, ".." },
1016 	{ 0, DIRBLKSIZ, 0, 0 },
1017 };
1018 #endif
1019 char buf[MAXBSIZE];
1020 static void copy_dir(struct direct *, struct direct *);
1021 
1022 int
1023 fsinit(const struct timeval *tv, mode_t mfsmode, uid_t mfsuid, gid_t mfsgid)
1024 {
1025 	union dinode node;
1026 	int i;
1027 	int qblocks = 0;
1028 	int qinos = 0;
1029 	uint8_t q2h_hash_shift;
1030 	uint16_t q2h_hash_mask;
1031 #ifdef LOSTDIR
1032 	int dirblksiz = DIRBLKSIZ;
1033 	if (isappleufs)
1034 		dirblksiz = APPLEUFS_DIRBLKSIZ;
1035 	int nextino = LOSTFOUNDINO+1;
1036 #else
1037 	int nextino = ROOTINO+1;
1038 #endif
1039 
1040 	/*
1041 	 * initialize the node
1042 	 */
1043 
1044 #ifdef LOSTDIR
1045 	/*
1046 	 * create the lost+found directory
1047 	 */
1048 	memset(&node, 0, sizeof(node));
1049 	if (Oflag == 0) {
1050 		(void)makedir((struct direct *)olost_found_dir, 2);
1051 		for (i = dirblksiz; i < sblock.fs_bsize; i += dirblksiz)
1052 			copy_dir((struct direct*)&olost_found_dir[2],
1053 				(struct direct*)&buf[i]);
1054 	} else {
1055 		(void)makedir(lost_found_dir, 2);
1056 		for (i = dirblksiz; i < sblock.fs_bsize; i += dirblksiz)
1057 			copy_dir(&lost_found_dir[2], (struct direct*)&buf[i]);
1058 	}
1059 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
1060 		node.dp1.di_atime = tv->tv_sec;
1061 		node.dp1.di_atimensec = tv->tv_usec * 1000;
1062 		node.dp1.di_mtime = tv->tv_sec;
1063 		node.dp1.di_mtimensec = tv->tv_usec * 1000;
1064 		node.dp1.di_ctime = tv->tv_sec;
1065 		node.dp1.di_ctimensec = tv->tv_usec * 1000;
1066 		node.dp1.di_mode = IFDIR | UMASK;
1067 		node.dp1.di_nlink = 2;
1068 		node.dp1.di_size = sblock.fs_bsize;
1069 		node.dp1.di_db[0] = alloc(node.dp1.di_size, node.dp1.di_mode);
1070 		if (node.dp1.di_db[0] == 0)
1071 			return (0);
1072 		node.dp1.di_blocks = btodb(fragroundup(&sblock,
1073 		    node.dp1.di_size));
1074 		qblocks += node.dp1.di_blocks;
1075 		node.dp1.di_uid = geteuid();
1076 		node.dp1.di_gid = getegid();
1077 		wtfs(fsbtodb(&sblock, node.dp1.di_db[0]), node.dp1.di_size,
1078 		    buf);
1079 	} else {
1080 		node.dp2.di_atime = tv->tv_sec;
1081 		node.dp2.di_atimensec = tv->tv_usec * 1000;
1082 		node.dp2.di_mtime = tv->tv_sec;
1083 		node.dp2.di_mtimensec = tv->tv_usec * 1000;
1084 		node.dp2.di_ctime = tv->tv_sec;
1085 		node.dp2.di_ctimensec = tv->tv_usec * 1000;
1086 		node.dp2.di_birthtime = tv->tv_sec;
1087 		node.dp2.di_birthnsec = tv->tv_usec * 1000;
1088 		node.dp2.di_mode = IFDIR | UMASK;
1089 		node.dp2.di_nlink = 2;
1090 		node.dp2.di_size = sblock.fs_bsize;
1091 		node.dp2.di_db[0] = alloc(node.dp2.di_size, node.dp2.di_mode);
1092 		if (node.dp2.di_db[0] == 0)
1093 			return (0);
1094 		node.dp2.di_blocks = btodb(fragroundup(&sblock,
1095 		    node.dp2.di_size));
1096 		qblocks += node.dp2.di_blocks;
1097 		node.dp2.di_uid = geteuid();
1098 		node.dp2.di_gid = getegid();
1099 		wtfs(fsbtodb(&sblock, node.dp2.di_db[0]), node.dp2.di_size,
1100 		    buf);
1101 	}
1102 	qinos++;
1103 	iput(&node, LOSTFOUNDINO);
1104 #endif
1105 	/*
1106 	 * create the root directory
1107 	 */
1108 	memset(&node, 0, sizeof(node));
1109 	if (Oflag <= 1) {
1110 		if (mfs) {
1111 			node.dp1.di_mode = IFDIR | mfsmode;
1112 			node.dp1.di_uid = mfsuid;
1113 			node.dp1.di_gid = mfsgid;
1114 		} else {
1115 			node.dp1.di_mode = IFDIR | UMASK;
1116 			node.dp1.di_uid = geteuid();
1117 			node.dp1.di_gid = getegid();
1118 		}
1119 		node.dp1.di_nlink = PREDEFDIR;
1120 		if (Oflag == 0)
1121 			node.dp1.di_size = makedir((struct direct *)oroot_dir,
1122 			    PREDEFDIR);
1123 		else
1124 			node.dp1.di_size = makedir(root_dir, PREDEFDIR);
1125 		node.dp1.di_db[0] = alloc(sblock.fs_fsize, node.dp1.di_mode);
1126 		if (node.dp1.di_db[0] == 0)
1127 			return (0);
1128 		node.dp1.di_blocks = btodb(fragroundup(&sblock,
1129 		    node.dp1.di_size));
1130 		qblocks += node.dp1.di_blocks;
1131 		wtfs(fsbtodb(&sblock, node.dp1.di_db[0]), sblock.fs_fsize, buf);
1132 	} else {
1133 		if (mfs) {
1134 			node.dp2.di_mode = IFDIR | mfsmode;
1135 			node.dp2.di_uid = mfsuid;
1136 			node.dp2.di_gid = mfsgid;
1137 		} else {
1138 			node.dp2.di_mode = IFDIR | UMASK;
1139 			node.dp2.di_uid = geteuid();
1140 			node.dp2.di_gid = getegid();
1141 		}
1142 		node.dp2.di_atime = tv->tv_sec;
1143 		node.dp2.di_atimensec = tv->tv_usec * 1000;
1144 		node.dp2.di_mtime = tv->tv_sec;
1145 		node.dp2.di_mtimensec = tv->tv_usec * 1000;
1146 		node.dp2.di_ctime = tv->tv_sec;
1147 		node.dp2.di_ctimensec = tv->tv_usec * 1000;
1148 		node.dp2.di_birthtime = tv->tv_sec;
1149 		node.dp2.di_birthnsec = tv->tv_usec * 1000;
1150 		node.dp2.di_nlink = PREDEFDIR;
1151 		node.dp2.di_size = makedir(root_dir, PREDEFDIR);
1152 		node.dp2.di_db[0] = alloc(sblock.fs_fsize, node.dp2.di_mode);
1153 		if (node.dp2.di_db[0] == 0)
1154 			return (0);
1155 		node.dp2.di_blocks = btodb(fragroundup(&sblock,
1156 		    node.dp2.di_size));
1157 		qblocks += node.dp2.di_blocks;
1158 		wtfs(fsbtodb(&sblock, node.dp2.di_db[0]), sblock.fs_fsize, buf);
1159 	}
1160 	qinos++;
1161 	iput(&node, ROOTINO);
1162 	/*
1163 	 * compute the size of the hash table
1164 	 * We know the smallest block size is 4k, so we can use 2k
1165 	 * for the hash table; as an entry is 8 bytes we can store
1166 	 * 256 entries. So let start q2h_hash_shift at 8
1167 	 */
1168 	for (q2h_hash_shift = 8;
1169 	    q2h_hash_shift < 15;
1170 	    q2h_hash_shift++) {
1171 		if ((sizeof(uint64_t) << (q2h_hash_shift + 1)) +
1172 		    sizeof(struct quota2_header) > (u_int)sblock.fs_bsize)
1173 			break;
1174 	}
1175 	q2h_hash_mask = (1 << q2h_hash_shift) - 1;
1176 	for (i = 0; i < MAXQUOTAS; i++) {
1177 		struct quota2_header *q2h;
1178 		struct quota2_entry *q2e;
1179 		uint64_t offset;
1180 		uid_t uid = (i == USRQUOTA ? geteuid() : getegid());
1181 
1182 		if ((quotas & FS_Q2_DO_TYPE(i)) == 0)
1183 			continue;
1184 		quota2_create_blk0(sblock.fs_bsize, buf, q2h_hash_shift,
1185 		    i, needswap);
1186 		/* grab an entry from header for root dir */
1187 		q2h = (void *)buf;
1188 		offset = ufs_rw64(q2h->q2h_free, needswap);
1189 		q2e = (void *)((char *)buf + offset);
1190 		q2h->q2h_free = q2e->q2e_next;
1191 		memcpy(q2e, &q2h->q2h_defentry, sizeof(*q2e));
1192 		q2e->q2e_uid = ufs_rw32(uid, needswap);
1193 		q2e->q2e_val[QL_BLOCK].q2v_cur = ufs_rw64(qblocks, needswap);
1194 		q2e->q2e_val[QL_FILE].q2v_cur = ufs_rw64(qinos, needswap);
1195 		/* add to the hash entry */
1196 		q2e->q2e_next = q2h->q2h_entries[uid & q2h_hash_mask];
1197 		q2h->q2h_entries[uid & q2h_hash_mask] =
1198 		    ufs_rw64(offset, needswap);
1199 
1200 		memset(&node, 0, sizeof(node));
1201 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
1202 			node.dp1.di_atime = tv->tv_sec;
1203 			node.dp1.di_atimensec = tv->tv_usec * 1000;
1204 			node.dp1.di_mtime = tv->tv_sec;
1205 			node.dp1.di_mtimensec = tv->tv_usec * 1000;
1206 			node.dp1.di_ctime = tv->tv_sec;
1207 			node.dp1.di_ctimensec = tv->tv_usec * 1000;
1208 			node.dp1.di_mode = IFREG;
1209 			node.dp1.di_nlink = 1;
1210 			node.dp1.di_size = sblock.fs_bsize;
1211 			node.dp1.di_db[0] =
1212 			    alloc(node.dp1.di_size, node.dp1.di_mode);
1213 			if (node.dp1.di_db[0] == 0)
1214 				return (0);
1215 			node.dp1.di_blocks = btodb(fragroundup(&sblock,
1216 			    node.dp1.di_size));
1217 			node.dp1.di_uid = geteuid();
1218 			node.dp1.di_gid = getegid();
1219 			wtfs(fsbtodb(&sblock, node.dp1.di_db[0]),
1220 			     node.dp1.di_size, buf);
1221 		} else {
1222 			node.dp2.di_atime = tv->tv_sec;
1223 			node.dp2.di_atimensec = tv->tv_usec * 1000;
1224 			node.dp2.di_mtime = tv->tv_sec;
1225 			node.dp2.di_mtimensec = tv->tv_usec * 1000;
1226 			node.dp2.di_ctime = tv->tv_sec;
1227 			node.dp2.di_ctimensec = tv->tv_usec * 1000;
1228 			node.dp2.di_birthtime = tv->tv_sec;
1229 			node.dp2.di_birthnsec = tv->tv_usec * 1000;
1230 			node.dp2.di_mode = IFREG;
1231 			node.dp2.di_nlink = 1;
1232 			node.dp2.di_size = sblock.fs_bsize;
1233 			node.dp2.di_db[0] =
1234 			    alloc(node.dp2.di_size, node.dp2.di_mode);
1235 			if (node.dp2.di_db[0] == 0)
1236 				return (0);
1237 			node.dp2.di_blocks = btodb(fragroundup(&sblock,
1238 			    node.dp2.di_size));
1239 			node.dp2.di_uid = geteuid();
1240 			node.dp2.di_gid = getegid();
1241 			wtfs(fsbtodb(&sblock, node.dp2.di_db[0]),
1242 			    node.dp2.di_size, buf);
1243 		}
1244 		iput(&node, nextino);
1245 		sblock.fs_quotafile[i] = nextino;
1246 		nextino++;
1247 	}
1248 	return (1);
1249 }
1250 
1251 /*
1252  * construct a set of directory entries in "buf".
1253  * return size of directory.
1254  */
1255 int
1256 makedir(struct direct *protodir, int entries)
1257 {
1258 	char *cp;
1259 	int i, spcleft;
1260 	int dirblksiz = DIRBLKSIZ;
1261 	if (isappleufs)
1262 		dirblksiz = APPLEUFS_DIRBLKSIZ;
1263 
1264 	memset(buf, 0, DIRBLKSIZ);
1265 	spcleft = dirblksiz;
1266 	for (cp = buf, i = 0; i < entries - 1; i++) {
1267 		protodir[i].d_reclen = DIRSIZ(Oflag == 0, &protodir[i], 0);
1268 		copy_dir(&protodir[i], (struct direct*)cp);
1269 		cp += protodir[i].d_reclen;
1270 		spcleft -= protodir[i].d_reclen;
1271 	}
1272 	protodir[i].d_reclen = spcleft;
1273 	copy_dir(&protodir[i], (struct direct*)cp);
1274 	return (dirblksiz);
1275 }
1276 
1277 /*
1278  * allocate a block or frag
1279  */
1280 daddr_t
1281 alloc(int size, int mode)
1282 {
1283 	int i, frag;
1284 	daddr_t d, blkno;
1285 
1286 	rdfs(fsbtodb(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
1287 	/* fs -> host byte order */
1288 	if (needswap)
1289 		ffs_cg_swap(&acg, &acg, &sblock);
1290 	if (acg.cg_magic != CG_MAGIC) {
1291 		printf("cg 0: bad magic number\n");
1292 		return (0);
1293 	}
1294 	if (acg.cg_cs.cs_nbfree == 0) {
1295 		printf("first cylinder group ran out of space\n");
1296 		return (0);
1297 	}
1298 	for (d = 0; d < acg.cg_ndblk; d += sblock.fs_frag)
1299 		if (isblock(&sblock, cg_blksfree(&acg, 0),
1300 		    d >> sblock.fs_fragshift))
1301 			goto goth;
1302 	printf("internal error: can't find block in cyl 0\n");
1303 	return (0);
1304 goth:
1305 	blkno = fragstoblks(&sblock, d);
1306 	clrblock(&sblock, cg_blksfree(&acg, 0), blkno);
1307 	if (sblock.fs_contigsumsize > 0)
1308 		clrbit(cg_clustersfree(&acg, 0), blkno);
1309 	acg.cg_cs.cs_nbfree--;
1310 	sblock.fs_cstotal.cs_nbfree--;
1311 	fscs_0->cs_nbfree--;
1312 	if (mode & IFDIR) {
1313 		acg.cg_cs.cs_ndir++;
1314 		sblock.fs_cstotal.cs_ndir++;
1315 		fscs_0->cs_ndir++;
1316 	}
1317 	if (Oflag <= 1) {
1318 		int cn = old_cbtocylno(&sblock, d);
1319 		old_cg_blktot(&acg, 0)[cn]--;
1320 		old_cg_blks(&sblock, &acg,
1321 		    cn, 0)[old_cbtorpos(&sblock, d)]--;
1322 	}
1323 	if (size != sblock.fs_bsize) {
1324 		frag = howmany(size, sblock.fs_fsize);
1325 		fscs_0->cs_nffree += sblock.fs_frag - frag;
1326 		sblock.fs_cstotal.cs_nffree += sblock.fs_frag - frag;
1327 		acg.cg_cs.cs_nffree += sblock.fs_frag - frag;
1328 		acg.cg_frsum[sblock.fs_frag - frag]++;
1329 		for (i = frag; i < sblock.fs_frag; i++)
1330 			setbit(cg_blksfree(&acg, 0), d + i);
1331 	}
1332 	/* host -> fs byte order */
1333 	if (needswap)
1334 		ffs_cg_swap(&acg, &acg, &sblock);
1335 	wtfs(fsbtodb(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
1336 	return (d);
1337 }
1338 
1339 /*
1340  * Allocate an inode on the disk
1341  */
1342 static void
1343 iput(union dinode *ip, ino_t ino)
1344 {
1345 	daddr_t d;
1346 	int i;
1347 	struct ufs1_dinode *dp1;
1348 	struct ufs2_dinode *dp2;
1349 
1350 	rdfs(fsbtodb(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
1351 	/* fs -> host byte order */
1352 	if (needswap)
1353 		ffs_cg_swap(&acg, &acg, &sblock);
1354 	if (acg.cg_magic != CG_MAGIC) {
1355 		printf("cg 0: bad magic number\n");
1356 		fserr(31);
1357 	}
1358 	acg.cg_cs.cs_nifree--;
1359 	setbit(cg_inosused(&acg, 0), ino);
1360 	/* host -> fs byte order */
1361 	if (needswap)
1362 		ffs_cg_swap(&acg, &acg, &sblock);
1363 	wtfs(fsbtodb(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
1364 	sblock.fs_cstotal.cs_nifree--;
1365 	fscs_0->cs_nifree--;
1366 	if (ino >= (ino_t)(sblock.fs_ipg * sblock.fs_ncg)) {
1367 		printf("fsinit: inode value out of range (%llu).\n",
1368 		    (unsigned long long)ino);
1369 		fserr(32);
1370 	}
1371 	d = fsbtodb(&sblock, ino_to_fsba(&sblock, ino));
1372 	rdfs(d, sblock.fs_bsize, (char *)iobuf);
1373 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
1374 		dp1 = (struct ufs1_dinode *)iobuf;
1375 		dp1 += ino_to_fsbo(&sblock, ino);
1376 		if (needswap) {
1377 			ffs_dinode1_swap(&ip->dp1, dp1);
1378 			/* ffs_dinode1_swap() doesn't swap blocks addrs */
1379 			for (i=0; i<NDADDR + NIADDR; i++)
1380 			    dp1->di_db[i] = bswap32(ip->dp1.di_db[i]);
1381 		} else
1382 			*dp1 = ip->dp1;
1383 		dp1->di_gen = arc4random() & INT32_MAX;
1384 	} else {
1385 		dp2 = (struct ufs2_dinode *)iobuf;
1386 		dp2 += ino_to_fsbo(&sblock, ino);
1387 		if (needswap) {
1388 			ffs_dinode2_swap(&ip->dp2, dp2);
1389 			for (i=0; i<NDADDR + NIADDR; i++)
1390 			    dp2->di_db[i] = bswap64(ip->dp2.di_db[i]);
1391 		} else
1392 			*dp2 = ip->dp2;
1393 		dp2->di_gen = arc4random() & INT32_MAX;
1394 	}
1395 	wtfs(d, sblock.fs_bsize, iobuf);
1396 }
1397 
1398 /*
1399  * read a block from the file system
1400  */
1401 void
1402 rdfs(daddr_t bno, int size, void *bf)
1403 {
1404 	int n;
1405 	off_t offset;
1406 
1407 #ifdef MFS
1408 	if (mfs) {
1409 		if (Nflag)
1410 			memset(bf, 0, size);
1411 		else
1412 			memmove(bf, membase + bno * sectorsize, size);
1413 		return;
1414 	}
1415 #endif
1416 	offset = bno;
1417 	n = pread(fsi, bf, size, offset * sectorsize);
1418 	if (n != size) {
1419 		printf("rdfs: read error for sector %lld: %s\n",
1420 		    (long long)bno, strerror(errno));
1421 		exit(34);
1422 	}
1423 }
1424 
1425 /*
1426  * write a block to the file system
1427  */
1428 void
1429 wtfs(daddr_t bno, int size, void *bf)
1430 {
1431 	int n;
1432 	off_t offset;
1433 
1434 	if (Nflag)
1435 		return;
1436 #ifdef MFS
1437 	if (mfs) {
1438 		memmove(membase + bno * sectorsize, bf, size);
1439 		return;
1440 	}
1441 #endif
1442 	offset = bno;
1443 	n = pwrite(fso, bf, size, offset * sectorsize);
1444 	if (n != size) {
1445 		printf("wtfs: write error for sector %lld: %s\n",
1446 		    (long long)bno, strerror(errno));
1447 		exit(36);
1448 	}
1449 }
1450 
1451 /*
1452  * check if a block is available
1453  */
1454 int
1455 isblock(struct fs *fs, unsigned char *cp, int h)
1456 {
1457 	unsigned char mask;
1458 
1459 	switch (fs->fs_fragshift) {
1460 	case 3:
1461 		return (cp[h] == 0xff);
1462 	case 2:
1463 		mask = 0x0f << ((h & 0x1) << 2);
1464 		return ((cp[h >> 1] & mask) == mask);
1465 	case 1:
1466 		mask = 0x03 << ((h & 0x3) << 1);
1467 		return ((cp[h >> 2] & mask) == mask);
1468 	case 0:
1469 		mask = 0x01 << (h & 0x7);
1470 		return ((cp[h >> 3] & mask) == mask);
1471 	default:
1472 #ifdef STANDALONE
1473 		printf("isblock bad fs_fragshift %d\n", fs->fs_fragshift);
1474 #else
1475 		fprintf(stderr, "isblock bad fs_fragshift %d\n",
1476 		    fs->fs_fragshift);
1477 #endif
1478 		return (0);
1479 	}
1480 }
1481 
1482 /*
1483  * take a block out of the map
1484  */
1485 void
1486 clrblock(struct fs *fs, unsigned char *cp, int h)
1487 {
1488 	switch ((fs)->fs_fragshift) {
1489 	case 3:
1490 		cp[h] = 0;
1491 		return;
1492 	case 2:
1493 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
1494 		return;
1495 	case 1:
1496 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
1497 		return;
1498 	case 0:
1499 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
1500 		return;
1501 	default:
1502 #ifdef STANDALONE
1503 		printf("clrblock bad fs_fragshift %d\n", fs->fs_fragshift);
1504 #else
1505 		fprintf(stderr, "clrblock bad fs_fragshift %d\n",
1506 		    fs->fs_fragshift);
1507 #endif
1508 		return;
1509 	}
1510 }
1511 
1512 /*
1513  * put a block into the map
1514  */
1515 void
1516 setblock(struct fs *fs, unsigned char *cp, int h)
1517 {
1518 	switch (fs->fs_fragshift) {
1519 	case 3:
1520 		cp[h] = 0xff;
1521 		return;
1522 	case 2:
1523 		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
1524 		return;
1525 	case 1:
1526 		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
1527 		return;
1528 	case 0:
1529 		cp[h >> 3] |= (0x01 << (h & 0x7));
1530 		return;
1531 	default:
1532 #ifdef STANDALONE
1533 		printf("setblock bad fs_frag %d\n", fs->fs_fragshift);
1534 #else
1535 		fprintf(stderr, "setblock bad fs_fragshift %d\n",
1536 		    fs->fs_fragshift);
1537 #endif
1538 		return;
1539 	}
1540 }
1541 
1542 /* copy a direntry to a buffer, in fs byte order */
1543 static void
1544 copy_dir(struct direct *dir, struct direct *dbuf)
1545 {
1546 	memcpy(dbuf, dir, DIRSIZ(Oflag == 0, dir, 0));
1547 	if (needswap) {
1548 		dbuf->d_ino = bswap32(dir->d_ino);
1549 		dbuf->d_reclen = bswap16(dir->d_reclen);
1550 		if (Oflag == 0)
1551 			((struct odirect*)dbuf)->d_namlen =
1552 				bswap16(((struct odirect*)dir)->d_namlen);
1553 	}
1554 }
1555 
1556 static int
1557 ilog2(int val)
1558 {
1559 	u_int n;
1560 
1561 	for (n = 0; n < sizeof(n) * CHAR_BIT; n++)
1562 		if (1 << n == val)
1563 			return (n);
1564 	errx(1, "ilog2: %d is not a power of 2\n", val);
1565 }
1566 
1567 static void
1568 zap_old_sblock(int sblkoff)
1569 {
1570 	static int cg0_data;
1571 	uint32_t oldfs[SBLOCKSIZE / 4];
1572 	static const struct fsm {
1573 		uint32_t	offset;
1574 		uint32_t	magic;
1575 		uint32_t	mask;
1576 	} fs_magics[] = {
1577 		{offsetof(struct fs, fs_magic)/4, FS_UFS1_MAGIC, ~0u},
1578 		{offsetof(struct fs, fs_magic)/4, FS_UFS2_MAGIC, ~0u},
1579 		{0, 0x70162, ~0u},		/* LFS_MAGIC */
1580 		{14, 0xef53, 0xffff},		/* EXT2FS (little) */
1581 		{14, 0xef530000, 0xffff0000},	/* EXT2FS (big) */
1582 		{.offset = ~0u},
1583 	};
1584 	const struct fsm *fsm;
1585 
1586 	if (Nflag)
1587 		return;
1588 
1589 	if (sblkoff == 0)	/* Why did UFS2 add support for this?  sigh. */
1590 		return;
1591 
1592 	if (cg0_data == 0)
1593 		/* For FFSv1 this could include all the inodes. */
1594 		cg0_data = cgsblock(&sblock, 0) * sblock.fs_fsize + iobufsize;
1595 
1596 	/* Ignore anything that is beyond our filesystem */
1597 	if ((sblkoff + SBLOCKSIZE)/sectorsize >= fssize)
1598 		return;
1599 	/* Zero anything inside our filesystem... */
1600 	if (sblkoff >= sblock.fs_sblockloc) {
1601 		/* ...unless we will write that area anyway */
1602 		if (sblkoff >= cg0_data)
1603 			wtfs(sblkoff / sectorsize,
1604 			    roundup(sizeof sblock, sectorsize), iobuf);
1605 		return;
1606 	}
1607 
1608 	/* The sector might contain boot code, so we must validate it */
1609 	rdfs(sblkoff/sectorsize, sizeof oldfs, &oldfs);
1610 	for (fsm = fs_magics; ; fsm++) {
1611 		uint32_t v;
1612 		if (fsm->mask == 0)
1613 			return;
1614 		v = oldfs[fsm->offset];
1615 		if ((v & fsm->mask) == fsm->magic ||
1616 		    (bswap32(v) & fsm->mask) == fsm->magic)
1617 			break;
1618 	}
1619 
1620 	/* Just zap the magic number */
1621 	oldfs[fsm->offset] = 0;
1622 	wtfs(sblkoff/sectorsize, sizeof oldfs, &oldfs);
1623 }
1624 
1625 
1626 #ifdef MFS
1627 /*
1628  * XXX!
1629  * Attempt to guess how much more space is available for process data.  The
1630  * heuristic we use is
1631  *
1632  *	max_data_limit - (sbrk(0) - etext) - 128kB
1633  *
1634  * etext approximates that start address of the data segment, and the 128kB
1635  * allows some slop for both segment gap between text and data, and for other
1636  * (libc) malloc usage.
1637  */
1638 static void
1639 calc_memfree(void)
1640 {
1641 	extern char etext;
1642 	struct rlimit rlp;
1643 	u_long base;
1644 
1645 	base = (u_long)sbrk(0) - (u_long)&etext;
1646 	if (getrlimit(RLIMIT_DATA, &rlp) < 0)
1647 		perror("getrlimit");
1648 	rlp.rlim_cur = rlp.rlim_max;
1649 	if (setrlimit(RLIMIT_DATA, &rlp) < 0)
1650 		perror("setrlimit");
1651 	memleft = rlp.rlim_max - base - (128 * 1024);
1652 }
1653 
1654 /*
1655  * Internal version of malloc that trims the requested size if not enough
1656  * memory is available.
1657  */
1658 static void *
1659 mkfs_malloc(size_t size)
1660 {
1661 	u_long pgsz;
1662 	caddr_t *memory;
1663 
1664 	if (size == 0)
1665 		return (NULL);
1666 	if (memleft == 0)
1667 		calc_memfree();
1668 
1669 	pgsz = getpagesize() - 1;
1670 	size = (size + pgsz) &~ pgsz;
1671 	if (size > memleft)
1672 		size = memleft;
1673 	memleft -= size;
1674 	memory = mmap(0, size, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
1675 	    -1, 0);
1676 	return memory != MAP_FAILED ? memory : NULL;
1677 }
1678 #endif	/* MFS */
1679