xref: /netbsd-src/sbin/newfs/mkfs.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: mkfs.c,v 1.122 2014/04/26 14:15:08 martin 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 1.122 2014/04/26 14:15:08 martin 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 *mkfs_malloc(size_t size);
125 #endif
126 
127 /*
128  * make file system for cylinder-group style file systems
129  */
130 #define	UMASK		0755
131 
132 union {
133 	struct fs fs;
134 	char data[SBLOCKSIZE];
135 } fsun;
136 #define	sblock	fsun.fs
137 
138 union {
139 	struct quota2_header q2h;
140 	char data[MAXBSIZE];
141 } buf;
142 
143 struct	csum *fscs_0;		/* first block of cylinder summaries */
144 struct	csum *fscs_next;	/* place for next summary */
145 struct	csum *fscs_end;		/* end of summary buffer */
146 struct	csum *fscs_reset;	/* place for next summary after write */
147 uint	fs_csaddr;		/* fragment number to write to */
148 
149 union {
150 	struct cg cg;
151 	char pad[MAXBSIZE];
152 } cgun;
153 #define	acg	cgun.cg
154 
155 #define DIP(dp, field) \
156 	((sblock.fs_magic == FS_UFS1_MAGIC) ? \
157 	(dp)->dp1.di_##field : (dp)->dp2.di_##field)
158 
159 #define EXT2FS_SBOFF	1024	/* XXX: SBOFF in <ufs/ext2fs/ext2fs.h> */
160 
161 char *iobuf;
162 int iobufsize;			/* size to end of 2nd inode block */
163 int iobuf_memsize;		/* Actual buffer size */
164 
165 int	fsi, fso;
166 
167 static void
168 fserr(int num)
169 {
170 #ifdef GARBAGE
171 	extern int Gflag;
172 
173 	if (Gflag)
174 		return;
175 #endif
176 	exit(num);
177 }
178 
179 void
180 mkfs(const char *fsys, int fi, int fo,
181     mode_t mfsmode, uid_t mfsuid, gid_t mfsgid)
182 {
183 	uint fragsperinodeblk, ncg, u;
184 	uint cgzero;
185 	uint64_t inodeblks, cgall;
186 	int32_t cylno, i, csfrags;
187 	int inodes_per_cg;
188 	struct timeval tv;
189 	long long sizepb;
190 	int len, col, delta, fld_width, max_cols;
191 	struct winsize winsize;
192 
193 #ifndef STANDALONE
194 	gettimeofday(&tv, NULL);
195 #endif
196 #ifdef MFS
197 	if (mfs && !Nflag) {
198 		if ((membase = mkfs_malloc(fssize * sectorsize)) == NULL)
199 			exit(12);
200 	}
201 #endif
202 	fsi = fi;
203 	fso = fo;
204 	if (Oflag == 0) {
205 		sblock.fs_old_inodefmt = FS_42INODEFMT;
206 		sblock.fs_maxsymlinklen = 0;
207 		sblock.fs_old_flags = 0;
208 	} else {
209 		sblock.fs_old_inodefmt = FS_44INODEFMT;
210 		sblock.fs_maxsymlinklen = (Oflag == 1 ? UFS1_MAXSYMLINKLEN :
211 		    UFS2_MAXSYMLINKLEN);
212 		sblock.fs_old_flags = FS_FLAGS_UPDATED;
213 		if (isappleufs)
214 			sblock.fs_old_flags = 0;
215 		sblock.fs_flags = 0;
216 	}
217 
218 	/*
219 	 * collect and verify the filesystem density info
220 	 */
221 	sblock.fs_avgfilesize = avgfilesize;
222 	sblock.fs_avgfpdir = avgfpdir;
223 	if (sblock.fs_avgfilesize <= 0) {
224 		printf("illegal expected average file size %d\n",
225 		    sblock.fs_avgfilesize);
226 		fserr(14);
227 	}
228 	if (sblock.fs_avgfpdir <= 0) {
229 		printf("illegal expected number of files per directory %d\n",
230 		    sblock.fs_avgfpdir);
231 		fserr(15);
232 	}
233 	/*
234 	 * collect and verify the block and fragment sizes
235 	 */
236 	sblock.fs_bsize = bsize;
237 	sblock.fs_fsize = fsize;
238 	if (!powerof2(sblock.fs_bsize)) {
239 		printf("block size must be a power of 2, not %d\n",
240 		    sblock.fs_bsize);
241 		fserr(16);
242 	}
243 	if (!powerof2(sblock.fs_fsize)) {
244 		printf("fragment size must be a power of 2, not %d\n",
245 		    sblock.fs_fsize);
246 		fserr(17);
247 	}
248 	if (sblock.fs_fsize < sectorsize) {
249 		printf("fragment size %d is too small, minimum is %d\n",
250 		    sblock.fs_fsize, sectorsize);
251 		fserr(18);
252 	}
253 	if (sblock.fs_bsize < MINBSIZE) {
254 		printf("block size %d is too small, minimum is %d\n",
255 		    sblock.fs_bsize, MINBSIZE);
256 		fserr(19);
257 	}
258 	if (sblock.fs_bsize > MAXBSIZE) {
259 		printf("block size %d is too large, maximum is %d\n",
260 		    sblock.fs_bsize, MAXBSIZE);
261 		fserr(19);
262 	}
263 	if (sblock.fs_bsize < sblock.fs_fsize) {
264 		printf("block size (%d) cannot be smaller than fragment size (%d)\n",
265 		    sblock.fs_bsize, sblock.fs_fsize);
266 		fserr(20);
267 	}
268 
269 	if (maxbsize < bsize || !powerof2(maxbsize)) {
270 		sblock.fs_maxbsize = sblock.fs_bsize;
271 	} else if (sblock.fs_maxbsize > FS_MAXCONTIG * sblock.fs_bsize) {
272 		sblock.fs_maxbsize = FS_MAXCONTIG * sblock.fs_bsize;
273 	} else {
274 		sblock.fs_maxbsize = maxbsize;
275 	}
276 	sblock.fs_maxcontig = maxcontig;
277 	if (sblock.fs_maxcontig < sblock.fs_maxbsize / sblock.fs_bsize) {
278 		sblock.fs_maxcontig = sblock.fs_maxbsize / sblock.fs_bsize;
279 		if (verbosity > 0)
280 			printf("Maxcontig raised to %d\n", sblock.fs_maxbsize);
281 	}
282 	if (sblock.fs_maxcontig > 1)
283 		sblock.fs_contigsumsize = MIN(sblock.fs_maxcontig,FS_MAXCONTIG);
284 
285 	sblock.fs_bmask = ~(sblock.fs_bsize - 1);
286 	sblock.fs_fmask = ~(sblock.fs_fsize - 1);
287 	sblock.fs_qbmask = ~sblock.fs_bmask;
288 	sblock.fs_qfmask = ~sblock.fs_fmask;
289 	for (sblock.fs_bshift = 0, i = sblock.fs_bsize; i > 1; i >>= 1)
290 		sblock.fs_bshift++;
291 	for (sblock.fs_fshift = 0, i = sblock.fs_fsize; i > 1; i >>= 1)
292 		sblock.fs_fshift++;
293 	sblock.fs_frag = ffs_numfrags(&sblock, sblock.fs_bsize);
294 	for (sblock.fs_fragshift = 0, i = sblock.fs_frag; i > 1; i >>= 1)
295 		sblock.fs_fragshift++;
296 	if (sblock.fs_frag > MAXFRAG) {
297 		printf("fragment size %d is too small, "
298 			"minimum with block size %d is %d\n",
299 		    sblock.fs_fsize, sblock.fs_bsize,
300 		    sblock.fs_bsize / MAXFRAG);
301 		fserr(21);
302 	}
303 	sblock.fs_fsbtodb = ilog2(sblock.fs_fsize / sectorsize);
304 	sblock.fs_size = FFS_DBTOFSB(&sblock, fssize);
305 	if (Oflag <= 1) {
306 		if ((uint64_t)sblock.fs_size >= 1ull << 31) {
307 			printf("Too many fragments (0x%" PRIx64
308 			    ") for a FFSv1 filesystem\n", sblock.fs_size);
309 			fserr(22);
310 		}
311 		sblock.fs_magic = FS_UFS1_MAGIC;
312 		sblock.fs_sblockloc = SBLOCK_UFS1;
313 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int32_t);
314 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs1_dinode);
315 		sblock.fs_old_cgoffset = 0;
316 		sblock.fs_old_cgmask = 0xffffffff;
317 		sblock.fs_old_size = sblock.fs_size;
318 		sblock.fs_old_rotdelay = 0;
319 		sblock.fs_old_rps = 60;
320 		sblock.fs_old_nspf = sblock.fs_fsize / sectorsize;
321 		sblock.fs_old_cpg = 1;
322 		sblock.fs_old_interleave = 1;
323 		sblock.fs_old_trackskew = 0;
324 		sblock.fs_old_cpc = 0;
325 		sblock.fs_old_postblformat = FS_DYNAMICPOSTBLFMT;
326 		sblock.fs_old_nrpos = 1;
327 	} else {
328 		sblock.fs_magic = FS_UFS2_MAGIC;
329 		sblock.fs_sblockloc = SBLOCK_UFS2;
330 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int64_t);
331 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs2_dinode);
332 	}
333 
334 	sblock.fs_sblkno =
335 	    roundup(howmany(sblock.fs_sblockloc + SBLOCKSIZE, sblock.fs_fsize),
336 		sblock.fs_frag);
337 	sblock.fs_cblkno = (daddr_t)(sblock.fs_sblkno +
338 	    roundup(howmany(SBLOCKSIZE, sblock.fs_fsize), sblock.fs_frag));
339 	sblock.fs_iblkno = sblock.fs_cblkno + sblock.fs_frag;
340 	sblock.fs_maxfilesize = sblock.fs_bsize * UFS_NDADDR - 1;
341 	for (sizepb = sblock.fs_bsize, i = 0; i < UFS_NIADDR; i++) {
342 		sizepb *= FFS_NINDIR(&sblock);
343 		sblock.fs_maxfilesize += sizepb;
344 	}
345 
346 	/*
347 	 * Calculate the number of blocks to put into each cylinder group.
348 	 *
349 	 * The cylinder group size is limited because the data structure
350 	 * must fit into a single block.
351 	 * We try to have as few cylinder groups as possible, with a proviso
352 	 * that we create at least MINCYLGRPS (==4) except for small
353 	 * filesystems.
354 	 *
355 	 * This algorithm works out how many blocks of inodes would be
356 	 * needed to fill the entire volume at the specified density.
357 	 * It then looks at how big the 'cylinder block' would have to
358 	 * be and, assuming that it is linearly related to the number
359 	 * of inodes and blocks how many cylinder groups are needed to
360 	 * keep the cylinder block below the filesystem block size.
361 	 *
362 	 * The cylinder groups are then all created with the average size.
363 	 *
364 	 * Space taken by the red tape on cylinder groups other than the
365 	 * first is ignored.
366 	 */
367 
368 	/* There must be space for 1 inode block and 2 data blocks */
369 	if (sblock.fs_size < sblock.fs_iblkno + 3 * sblock.fs_frag) {
370 		printf("Filesystem size %lld < minimum size of %d\n",
371 		    (long long)sblock.fs_size, sblock.fs_iblkno + 3 * sblock.fs_frag);
372 		fserr(23);
373 	}
374 	if (num_inodes != 0)
375 		inodeblks = howmany(num_inodes, FFS_INOPB(&sblock));
376 	else {
377 		/*
378 		 * Calculate 'per inode block' so we can allocate less than
379 		 * 1 fragment per inode - useful for /dev.
380 		 */
381 		fragsperinodeblk = MAX(ffs_numfrags(&sblock,
382 					(uint64_t)density * FFS_INOPB(&sblock)), 1);
383 		inodeblks = (sblock.fs_size - sblock.fs_iblkno) /
384 			(sblock.fs_frag + fragsperinodeblk);
385 	}
386 	if (inodeblks == 0)
387 		inodeblks = 1;
388 	/* Ensure that there are at least 2 data blocks (or we fail below) */
389 	if (inodeblks > (uint64_t)(sblock.fs_size - sblock.fs_iblkno)/sblock.fs_frag - 2)
390 		inodeblks = (sblock.fs_size-sblock.fs_iblkno)/sblock.fs_frag-2;
391 	/* Even UFS2 limits number of inodes to 2^31 (fs_ipg is int32_t) */
392 	if (inodeblks * FFS_INOPB(&sblock) >= 1ull << 31)
393 		inodeblks = ((1ull << 31) - NBBY) / FFS_INOPB(&sblock);
394 	/*
395 	 * See what would happen if we tried to use 1 cylinder group.
396 	 * Assume space linear, so work out number of cylinder groups needed.
397 	 */
398 	cgzero = CGSIZE_IF(&sblock, 0, 0);
399 	cgall = CGSIZE_IF(&sblock, inodeblks * FFS_INOPB(&sblock), sblock.fs_size);
400 	ncg = howmany(cgall - cgzero, sblock.fs_bsize - cgzero);
401 	if (ncg < MINCYLGRPS) {
402 		/*
403 		 * We would like to allocate MINCLYGRPS cylinder groups,
404 		 * but for small file sytems (especially ones with a lot
405 		 * of inodes) this is not desirable (or possible).
406 		 */
407 		u = sblock.fs_size / 2 / (sblock.fs_iblkno +
408 						inodeblks * sblock.fs_frag);
409 		if (u > ncg)
410 			ncg = u;
411 		if (ncg > MINCYLGRPS)
412 			ncg = MINCYLGRPS;
413 		if (ncg > inodeblks)
414 			ncg = inodeblks;
415 	}
416 	/*
417 	 * Put an equal number of blocks in each cylinder group.
418 	 * Round up so we don't have more fragments in the last CG than
419 	 * the earlier ones (does that matter?), but kill a block if the
420 	 * CGSIZE becomes too big (only happens if there are a lot of CGs).
421 	 */
422 	sblock.fs_fpg = roundup(howmany(sblock.fs_size, ncg), sblock.fs_frag);
423 	/* Round up the fragments/group so the bitmap bytes are full */
424 	sblock.fs_fpg = roundup(sblock.fs_fpg, NBBY);
425 	inodes_per_cg = ((inodeblks - 1) / ncg + 1) * FFS_INOPB(&sblock);
426 
427 	i = CGSIZE_IF(&sblock, inodes_per_cg, sblock.fs_fpg);
428 	if (i > sblock.fs_bsize) {
429 		sblock.fs_fpg -= (i - sblock.fs_bsize) * NBBY;
430 		/* ... and recalculate how many cylinder groups we now need */
431 		ncg = howmany(sblock.fs_size, sblock.fs_fpg);
432 		inodes_per_cg = ((inodeblks - 1) / ncg + 1) * FFS_INOPB(&sblock);
433 	}
434 	sblock.fs_ipg = inodes_per_cg;
435 	/* Sanity check on our sums... */
436 	if ((int)CGSIZE(&sblock) > sblock.fs_bsize) {
437 		printf("CGSIZE miscalculated %d > %d\n",
438 		    (int)CGSIZE(&sblock), sblock.fs_bsize);
439 		fserr(24);
440 	}
441 
442 	sblock.fs_dblkno = sblock.fs_iblkno + sblock.fs_ipg / FFS_INOPF(&sblock);
443 	/* Check that the last cylinder group has enough space for the inodes */
444 	i = sblock.fs_size - sblock.fs_fpg * (ncg - 1ull);
445 	if (i < sblock.fs_dblkno) {
446 		/*
447 		 * Since we make all the cylinder groups the same size, the
448 		 * last will only be small if there are a large number of
449 		 * cylinder groups. If we pull even a fragment from each
450 		 * of the other groups then the last CG will be overfull.
451 		 * So we just kill the last CG.
452 		 */
453 		ncg--;
454 		sblock.fs_size -= i;
455 	}
456 	sblock.fs_ncg = ncg;
457 
458 	sblock.fs_cgsize = ffs_fragroundup(&sblock, CGSIZE(&sblock));
459 	if (Oflag <= 1) {
460 		sblock.fs_old_spc = sblock.fs_fpg * sblock.fs_old_nspf;
461 		sblock.fs_old_nsect = sblock.fs_old_spc;
462 		sblock.fs_old_npsect = sblock.fs_old_spc;
463 		sblock.fs_old_ncyl = sblock.fs_ncg;
464 	}
465 
466 	/*
467 	 * Cylinder group summary information for each cylinder is written
468 	 * into the first cylinder group.
469 	 * Write this fragment by fragment, but doing the first CG last
470 	 * (after we've taken stuff off for the structure itself and the
471 	 * root directory.
472 	 */
473 	sblock.fs_csaddr = cgdmin(&sblock, 0);
474 	sblock.fs_cssize =
475 	    ffs_fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));
476 	if (512 % sizeof *fscs_0)
477 		errx(1, "cylinder group summary doesn't fit in sectors");
478 	fscs_0 = mmap(0, 2 * sblock.fs_fsize, PROT_READ|PROT_WRITE,
479 			MAP_ANON|MAP_PRIVATE, -1, 0);
480 	if (fscs_0 == MAP_FAILED)
481 		exit(39);
482 	memset(fscs_0, 0, 2 * sblock.fs_fsize);
483 	fs_csaddr = sblock.fs_csaddr;
484 	fscs_next = fscs_0;
485 	fscs_end = (void *)((char *)fscs_0 + 2 * sblock.fs_fsize);
486 	fscs_reset = (void *)((char *)fscs_0 + sblock.fs_fsize);
487 	/*
488 	 * fill in remaining fields of the super block
489 	 */
490 	sblock.fs_sbsize = ffs_fragroundup(&sblock, sizeof(struct fs));
491 	if (sblock.fs_sbsize > SBLOCKSIZE)
492 		sblock.fs_sbsize = SBLOCKSIZE;
493 	sblock.fs_minfree = minfree;
494 	sblock.fs_maxcontig = maxcontig;
495 	sblock.fs_maxbpg = maxbpg;
496 	sblock.fs_optim = opt;
497 	sblock.fs_cgrotor = 0;
498 	sblock.fs_pendingblocks = 0;
499 	sblock.fs_pendinginodes = 0;
500 	sblock.fs_cstotal.cs_ndir = 0;
501 	sblock.fs_cstotal.cs_nbfree = 0;
502 	sblock.fs_cstotal.cs_nifree = 0;
503 	sblock.fs_cstotal.cs_nffree = 0;
504 	sblock.fs_fmod = 0;
505 	sblock.fs_ronly = 0;
506 	sblock.fs_state = 0;
507 	sblock.fs_clean = FS_ISCLEAN;
508 	sblock.fs_ronly = 0;
509 	sblock.fs_id[0] = (long)tv.tv_sec;	/* XXXfvdl huh? */
510 	sblock.fs_id[1] = arc4random() & INT32_MAX;
511 	sblock.fs_fsmnt[0] = '\0';
512 	csfrags = howmany(sblock.fs_cssize, sblock.fs_fsize);
513 	sblock.fs_dsize = sblock.fs_size - sblock.fs_sblkno -
514 	    sblock.fs_ncg * (sblock.fs_dblkno - sblock.fs_sblkno);
515 	sblock.fs_cstotal.cs_nbfree =
516 	    ffs_fragstoblks(&sblock, sblock.fs_dsize) -
517 	    howmany(csfrags, sblock.fs_frag);
518 	sblock.fs_cstotal.cs_nffree =
519 	    ffs_fragnum(&sblock, sblock.fs_size) +
520 	    (ffs_fragnum(&sblock, csfrags) > 0 ?
521 	    sblock.fs_frag - ffs_fragnum(&sblock, csfrags) : 0);
522 	sblock.fs_cstotal.cs_nifree = sblock.fs_ncg * sblock.fs_ipg - UFS_ROOTINO;
523 	sblock.fs_cstotal.cs_ndir = 0;
524 	sblock.fs_dsize -= csfrags;
525 	sblock.fs_time = tv.tv_sec;
526 	if (Oflag <= 1) {
527 		sblock.fs_old_time = tv.tv_sec;
528 		sblock.fs_old_dsize = sblock.fs_dsize;
529 		sblock.fs_old_csaddr = sblock.fs_csaddr;
530 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
531 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
532 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
533 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
534 	}
535 	/* add quota data in superblock */
536 	if (quotas) {
537 		sblock.fs_flags |= FS_DOQUOTA2;
538 		sblock.fs_quota_magic = Q2_HEAD_MAGIC;
539 		sblock.fs_quota_flags = quotas;
540 	}
541 	/*
542 	 * Dump out summary information about file system.
543 	 */
544 	if (verbosity > 0) {
545 #define	B2MBFACTOR (1 / (1024.0 * 1024.0))
546 		printf("%s: %.1fMB (%lld sectors) block size %d, "
547 		       "fragment size %d\n",
548 		    fsys, (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
549 		    (long long)FFS_FSBTODB(&sblock, sblock.fs_size),
550 		    sblock.fs_bsize, sblock.fs_fsize);
551 		printf("\tusing %d cylinder groups of %.2fMB, %d blks, "
552 		       "%d inodes.\n",
553 		    sblock.fs_ncg,
554 		    (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
555 		    sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
556 #undef B2MBFACTOR
557 	}
558 
559 	/*
560 	 * allocate space for superblock, cylinder group map, and
561 	 * two sets of inode blocks.
562 	 */
563 	if (sblock.fs_bsize < SBLOCKSIZE)
564 		iobufsize = SBLOCKSIZE + 3 * sblock.fs_bsize;
565 	else
566 		iobufsize = 4 * sblock.fs_bsize;
567 	iobuf_memsize = iobufsize;
568 	if (!mfs && sblock.fs_magic == FS_UFS1_MAGIC) {
569 		/* A larger buffer so we can write multiple inode blks */
570 		iobuf_memsize += 14 * sblock.fs_bsize;
571 	}
572 	for (;;) {
573 		iobuf = mmap(0, iobuf_memsize, PROT_READ|PROT_WRITE,
574 				MAP_ANON|MAP_PRIVATE, -1, 0);
575 		if (iobuf != MAP_FAILED)
576 			break;
577 		if (iobuf_memsize != iobufsize) {
578 			/* Try again with the smaller size */
579 			iobuf_memsize = iobufsize;
580 			continue;
581 		}
582 		printf("Cannot allocate I/O buffer\n");
583 		exit(38);
584 	}
585 	memset(iobuf, 0, iobuf_memsize);
586 
587 	/*
588 	 * We now start writing to the filesystem
589 	 */
590 
591 	if (!Nflag) {
592 		/*
593 		 * Validate the given file system size.
594 		 * Verify that its last block can actually be accessed.
595 		 * Convert to file system fragment sized units.
596 		 */
597 		if (fssize <= 0) {
598 			printf("preposterous size %lld\n", (long long)fssize);
599 			fserr(13);
600 		}
601 		wtfs(fssize - 1, sectorsize, iobuf);
602 
603 		/*
604 		 * Ensure there is nothing that looks like a filesystem
605 		 * superbock anywhere other than where ours will be.
606 		 * If fsck finds the wrong one all hell breaks loose!
607 		 */
608 		for (i = 0; ; i++) {
609 			static const int sblocklist[] = SBLOCKSEARCH;
610 			int sblkoff = sblocklist[i];
611 			int sz;
612 			if (sblkoff == -1)
613 				break;
614 			/* Remove main superblock */
615 			zap_old_sblock(sblkoff);
616 			/* and all possible locations for the first alternate */
617 			sblkoff += SBLOCKSIZE;
618 			for (sz = SBLOCKSIZE; sz <= 0x10000; sz <<= 1)
619 				zap_old_sblock(roundup(sblkoff, sz));
620 		}
621 		/*
622 		 * Also zap possible Ext2fs magic leftover to prevent
623 		 * kernel vfs_mountroot() and bootloaders from mis-recognizing
624 		 * this file system as Ext2fs.
625 		 */
626 		zap_old_sblock(EXT2FS_SBOFF);
627 
628 		if (isappleufs) {
629 			struct appleufslabel appleufs;
630 			ffs_appleufs_set(&appleufs, appleufs_volname,
631 			    tv.tv_sec, 0);
632 			wtfs(APPLEUFS_LABEL_OFFSET/sectorsize,
633 			    APPLEUFS_LABEL_SIZE, &appleufs);
634 		} else if (APPLEUFS_LABEL_SIZE % sectorsize == 0) {
635 			struct appleufslabel appleufs;
636 			/* Look for & zap any existing valid apple ufs labels */
637 			rdfs(APPLEUFS_LABEL_OFFSET/sectorsize,
638 			    APPLEUFS_LABEL_SIZE, &appleufs);
639 			if (ffs_appleufs_validate(fsys, &appleufs, NULL) == 0) {
640 				memset(&appleufs, 0, sizeof(appleufs));
641 				wtfs(APPLEUFS_LABEL_OFFSET/sectorsize,
642 				    APPLEUFS_LABEL_SIZE, &appleufs);
643 			}
644 		}
645 	}
646 
647 	/*
648 	 * Make a copy of the superblock into the buffer that we will be
649 	 * writing out in each cylinder group.
650 	 */
651 	memcpy(iobuf, &sblock, sizeof sblock);
652 	if (needswap)
653 		ffs_sb_swap(&sblock, (struct fs *)iobuf);
654 	if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0)
655 		memset(iobuf + offsetof(struct fs, fs_old_postbl_start),
656 		    0xff, 256);
657 
658 	if (verbosity >= 3)
659 		printf("super-block backups (for fsck_ffs -b #) at:\n");
660 	/* If we are printing more than one line of numbers, line up columns */
661 	fld_width = verbosity < 4 ? 1 : snprintf(NULL, 0, "%" PRIu64,
662 		(uint64_t)FFS_FSBTODB(&sblock, cgsblock(&sblock, sblock.fs_ncg-1)));
663 	/* Get terminal width */
664 	if (ioctl(fileno(stdout), TIOCGWINSZ, &winsize) == 0)
665 		max_cols = winsize.ws_col;
666 	else
667 		max_cols = 80;
668 	if (Nflag && verbosity == 3)
669 		/* Leave space to add " ..." after one row of numbers */
670 		max_cols -= 4;
671 #define BASE 0x10000	/* For some fixed-point maths */
672 	col = 0;
673 	delta = verbosity > 2 ? 0 : max_cols * BASE / sblock.fs_ncg;
674 	for (cylno = 0; cylno < sblock.fs_ncg; cylno++) {
675 		fflush(stdout);
676 		initcg(cylno, &tv);
677 		if (verbosity < 2)
678 			continue;
679 		if (delta > 0) {
680 			if (Nflag)
681 				/* No point doing dots for -N */
682 				break;
683 			/* Print dots scaled to end near RH margin */
684 			for (col += delta; col > BASE; col -= BASE)
685 				printf(".");
686 			continue;
687 		}
688 		/* Print superblock numbers */
689 		len = printf("%s%*" PRIu64 ",", col ? " " : "", fld_width,
690 		    (uint64_t)FFS_FSBTODB(&sblock, cgsblock(&sblock, cylno)));
691 		col += len;
692 		if (col + len < max_cols)
693 			/* Next number fits */
694 			continue;
695 		/* Next number won't fit, need a newline */
696 		if (verbosity <= 3) {
697 			/* Print dots for subsequent cylinder groups */
698 			delta = sblock.fs_ncg - cylno - 1;
699 			if (delta != 0) {
700 				if (Nflag) {
701 					printf(" ...");
702 					break;
703 				}
704 				delta = max_cols * BASE / delta;
705 			}
706 		}
707 		col = 0;
708 		printf("\n");
709 	}
710 #undef BASE
711 	if (col > 0)
712 		printf("\n");
713 	if (Nflag)
714 		exit(0);
715 
716 	/*
717 	 * Now construct the initial file system,
718 	 */
719 	if (fsinit(&tv, mfsmode, mfsuid, mfsgid) == 0 && mfs)
720 		errx(1, "Error making filesystem");
721 	sblock.fs_time = tv.tv_sec;
722 	if (Oflag <= 1) {
723 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
724 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
725 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
726 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
727 	}
728 	/*
729 	 * Write out the super-block and zeros until the first cg info
730 	 */
731 	i = cgsblock(&sblock, 0) * sblock.fs_fsize - sblock.fs_sblockloc,
732 	memset(iobuf, 0, i);
733 	memcpy(iobuf, &sblock, sizeof sblock);
734 	if (needswap)
735 		ffs_sb_swap(&sblock, (struct fs *)iobuf);
736 	if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0)
737 		memset(iobuf + offsetof(struct fs, fs_old_postbl_start),
738 		    0xff, 256);
739 	wtfs(sblock.fs_sblockloc / sectorsize, i, iobuf);
740 
741 	/* Write out first and last cylinder summary sectors */
742 	if (needswap)
743 		ffs_csum_swap(fscs_0, fscs_0, sblock.fs_fsize);
744 	wtfs(FFS_FSBTODB(&sblock, sblock.fs_csaddr), sblock.fs_fsize, fscs_0);
745 
746 	if (fscs_next > fscs_reset) {
747 		if (needswap)
748 			ffs_csum_swap(fscs_reset, fscs_reset, sblock.fs_fsize);
749 		fs_csaddr++;
750 		wtfs(FFS_FSBTODB(&sblock, fs_csaddr), sblock.fs_fsize, fscs_reset);
751 	}
752 
753 	/* mfs doesn't need these permanently allocated */
754 	munmap(iobuf, iobuf_memsize);
755 	munmap(fscs_0, 2 * sblock.fs_fsize);
756 }
757 
758 /*
759  * Initialize a cylinder group.
760  */
761 void
762 initcg(int cylno, const struct timeval *tv)
763 {
764 	daddr_t cbase, dmax;
765 	int32_t i, d, dlower, dupper, blkno;
766 	uint32_t u;
767 	struct ufs1_dinode *dp1;
768 	struct ufs2_dinode *dp2;
769 	int start;
770 
771 	/*
772 	 * Determine block bounds for cylinder group.
773 	 * Allow space for super block summary information in first
774 	 * cylinder group.
775 	 */
776 	cbase = cgbase(&sblock, cylno);
777 	dmax = cbase + sblock.fs_fpg;
778 	if (dmax > sblock.fs_size)
779 		dmax = sblock.fs_size;
780 	dlower = cgsblock(&sblock, cylno) - cbase;
781 	dupper = cgdmin(&sblock, cylno) - cbase;
782 	if (cylno == 0) {
783 		dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
784 		if (dupper >= cgstart(&sblock, cylno + 1)) {
785 			printf("\rToo many cylinder groups to fit summary "
786 				"information into first cylinder group\n");
787 			fserr(40);
788 		}
789 	}
790 	memset(&acg, 0, sblock.fs_cgsize);
791 	acg.cg_magic = CG_MAGIC;
792 	acg.cg_cgx = cylno;
793 	acg.cg_ndblk = dmax - cbase;
794 	if (sblock.fs_contigsumsize > 0)
795 		acg.cg_nclusterblks = acg.cg_ndblk >> sblock.fs_fragshift;
796 	start = &acg.cg_space[0] - (u_char *)(&acg.cg_firstfield);
797 	if (Oflag == 2) {
798 		acg.cg_time = tv->tv_sec;
799 		acg.cg_niblk = sblock.fs_ipg;
800 		acg.cg_initediblk = sblock.fs_ipg < 2 * FFS_INOPB(&sblock) ?
801 		    sblock.fs_ipg : 2 * FFS_INOPB(&sblock);
802 		acg.cg_iusedoff = start;
803 	} else {
804 		acg.cg_old_ncyl = sblock.fs_old_cpg;
805 		if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0 &&
806 		    (cylno == sblock.fs_ncg - 1))
807 			acg.cg_old_ncyl =
808 			    sblock.fs_old_ncyl % sblock.fs_old_cpg;
809 		acg.cg_old_time = tv->tv_sec;
810 		acg.cg_old_niblk = sblock.fs_ipg;
811 		acg.cg_old_btotoff = start;
812 		acg.cg_old_boff = acg.cg_old_btotoff +
813 		    sblock.fs_old_cpg * sizeof(int32_t);
814 		acg.cg_iusedoff = acg.cg_old_boff +
815 		    sblock.fs_old_cpg * sizeof(u_int16_t);
816 	}
817 	acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
818 	if (sblock.fs_contigsumsize <= 0) {
819 		acg.cg_nextfreeoff = acg.cg_freeoff +
820 		   howmany(sblock.fs_fpg, CHAR_BIT);
821 	} else {
822 		acg.cg_clustersumoff = acg.cg_freeoff +
823 		    howmany(sblock.fs_fpg, CHAR_BIT) - sizeof(int32_t);
824 		if (isappleufs) {
825 			/* Apple PR2216969 gives rationale for this change.
826 			 * I believe they were mistaken, but we need to
827 			 * duplicate it for compatibility.  -- dbj@NetBSD.org
828 			 */
829 			acg.cg_clustersumoff += sizeof(int32_t);
830 		}
831 		acg.cg_clustersumoff =
832 		    roundup(acg.cg_clustersumoff, sizeof(int32_t));
833 		acg.cg_clusteroff = acg.cg_clustersumoff +
834 		    (sblock.fs_contigsumsize + 1) * sizeof(int32_t);
835 		acg.cg_nextfreeoff = acg.cg_clusteroff +
836 		    howmany(ffs_fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
837 	}
838 	if (acg.cg_nextfreeoff > sblock.fs_cgsize) {
839 		printf("Panic: cylinder group too big\n");
840 		fserr(37);
841 	}
842 	acg.cg_cs.cs_nifree += sblock.fs_ipg;
843 	if (cylno == 0)
844 		for (u = 0; u < UFS_ROOTINO; u++) {
845 			setbit(cg_inosused(&acg, 0), u);
846 			acg.cg_cs.cs_nifree--;
847 		}
848 	if (cylno > 0) {
849 		/*
850 		 * In cylno 0, beginning space is reserved
851 		 * for boot and super blocks.
852 		 */
853 		for (d = 0, blkno = 0; d < dlower;) {
854 			setblock(&sblock, cg_blksfree(&acg, 0), blkno);
855 			if (sblock.fs_contigsumsize > 0)
856 				setbit(cg_clustersfree(&acg, 0), blkno);
857 			acg.cg_cs.cs_nbfree++;
858 			if (Oflag <= 1) {
859 				int cn = old_cbtocylno(&sblock, d);
860 				old_cg_blktot(&acg, 0)[cn]++;
861 				old_cg_blks(&sblock, &acg,
862 				    cn, 0)[old_cbtorpos(&sblock, d)]++;
863 			}
864 			d += sblock.fs_frag;
865 			blkno++;
866 		}
867 	}
868 	if ((i = (dupper & (sblock.fs_frag - 1))) != 0) {
869 		acg.cg_frsum[sblock.fs_frag - i]++;
870 		for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
871 			setbit(cg_blksfree(&acg, 0), dupper);
872 			acg.cg_cs.cs_nffree++;
873 		}
874 	}
875 	for (d = dupper, blkno = dupper >> sblock.fs_fragshift;
876 	     d + sblock.fs_frag <= acg.cg_ndblk; ) {
877 		setblock(&sblock, cg_blksfree(&acg, 0), blkno);
878 		if (sblock.fs_contigsumsize > 0)
879 			setbit(cg_clustersfree(&acg, 0), blkno);
880 		acg.cg_cs.cs_nbfree++;
881 		if (Oflag <= 1) {
882 			int cn = old_cbtocylno(&sblock, d);
883 			old_cg_blktot(&acg, 0)[cn]++;
884 			old_cg_blks(&sblock, &acg,
885 			    cn, 0)[old_cbtorpos(&sblock, d)]++;
886 		}
887 		d += sblock.fs_frag;
888 		blkno++;
889 	}
890 	if (d < acg.cg_ndblk) {
891 		acg.cg_frsum[acg.cg_ndblk - d]++;
892 		for (; d < acg.cg_ndblk; d++) {
893 			setbit(cg_blksfree(&acg, 0), d);
894 			acg.cg_cs.cs_nffree++;
895 		}
896 	}
897 	if (sblock.fs_contigsumsize > 0) {
898 		int32_t *sump = cg_clustersum(&acg, 0);
899 		u_char *mapp = cg_clustersfree(&acg, 0);
900 		int map = *mapp++;
901 		int bit = 1;
902 		int run = 0;
903 
904 		for (i = 0; i < acg.cg_nclusterblks; i++) {
905 			if ((map & bit) != 0) {
906 				run++;
907 			} else if (run != 0) {
908 				if (run > sblock.fs_contigsumsize)
909 					run = sblock.fs_contigsumsize;
910 				sump[run]++;
911 				run = 0;
912 			}
913 			if ((i & (CHAR_BIT - 1)) != (CHAR_BIT - 1)) {
914 				bit <<= 1;
915 			} else {
916 				map = *mapp++;
917 				bit = 1;
918 			}
919 		}
920 		if (run != 0) {
921 			if (run > sblock.fs_contigsumsize)
922 				run = sblock.fs_contigsumsize;
923 			sump[run]++;
924 		}
925 	}
926 	*fscs_next++ = acg.cg_cs;
927 	if (fscs_next == fscs_end) {
928 		/* write block of cylinder group summary info into cyl 0 */
929 		if (needswap)
930 			ffs_csum_swap(fscs_reset, fscs_reset, sblock.fs_fsize);
931 		fs_csaddr++;
932 		wtfs(FFS_FSBTODB(&sblock, fs_csaddr), sblock.fs_fsize, fscs_reset);
933 		fscs_next = fscs_reset;
934 		memset(fscs_next, 0, sblock.fs_fsize);
935 	}
936 	/*
937 	 * Write out the duplicate super block, the cylinder group map
938 	 * and two blocks worth of inodes in a single write.
939 	 */
940 	start = sblock.fs_bsize > SBLOCKSIZE ? sblock.fs_bsize : SBLOCKSIZE;
941 	memcpy(&iobuf[start], &acg, sblock.fs_cgsize);
942 	if (needswap)
943 		ffs_cg_swap(&acg, (struct cg*)&iobuf[start], &sblock);
944 	start += sblock.fs_bsize;
945 	dp1 = (struct ufs1_dinode *)(&iobuf[start]);
946 	dp2 = (struct ufs2_dinode *)(&iobuf[start]);
947 	for (i = MIN(sblock.fs_ipg, 2) * FFS_INOPB(&sblock); i != 0; i--) {
948 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
949 			/* No need to swap, it'll stay random */
950 			dp1->di_gen = arc4random() & INT32_MAX;
951 			dp1++;
952 		} else {
953 			dp2->di_gen = arc4random() & INT32_MAX;
954 			dp2++;
955 		}
956 	}
957 	wtfs(FFS_FSBTODB(&sblock, cgsblock(&sblock, cylno)), iobufsize, iobuf);
958 	/*
959 	 * For the old file system, we have to initialize all the inodes.
960 	 */
961 	if (sblock.fs_magic != FS_UFS1_MAGIC)
962 		return;
963 
964 	/* Write 'd' (usually 16 * fs_frag) file-system fragments at once */
965 	d = (iobuf_memsize - start) / sblock.fs_bsize * sblock.fs_frag;
966 	dupper = sblock.fs_ipg / FFS_INOPF(&sblock);
967 	for (i = 2 * sblock.fs_frag; i < dupper; i += d) {
968 		if (d > dupper - i)
969 			d = dupper - i;
970 		dp1 = (struct ufs1_dinode *)(&iobuf[start]);
971 		do
972 			dp1->di_gen = arc4random() & INT32_MAX;
973 		while ((char *)++dp1 < &iobuf[iobuf_memsize]);
974 		wtfs(FFS_FSBTODB(&sblock, cgimin(&sblock, cylno) + i),
975 		    d * sblock.fs_bsize / sblock.fs_frag, &iobuf[start]);
976 	}
977 }
978 
979 /*
980  * initialize the file system
981  */
982 
983 #ifdef LOSTDIR
984 #define	PREDEFDIR 3
985 #else
986 #define	PREDEFDIR 2
987 #endif
988 
989 struct direct root_dir[] = {
990 	{ UFS_ROOTINO, sizeof(struct direct), DT_DIR, 1, "." },
991 	{ UFS_ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
992 #ifdef LOSTDIR
993 	{ LOSTFOUNDINO, sizeof(struct direct), DT_DIR, 10, "lost+found" },
994 #endif
995 };
996 struct odirect {
997 	u_int32_t d_ino;
998 	u_int16_t d_reclen;
999 	u_int16_t d_namlen;
1000 	u_char	d_name[FFS_MAXNAMLEN + 1];
1001 } oroot_dir[] = {
1002 	{ UFS_ROOTINO, sizeof(struct direct), 1, "." },
1003 	{ UFS_ROOTINO, sizeof(struct direct), 2, ".." },
1004 #ifdef LOSTDIR
1005 	{ LOSTFOUNDINO, sizeof(struct direct), 10, "lost+found" },
1006 #endif
1007 };
1008 #ifdef LOSTDIR
1009 struct direct lost_found_dir[] = {
1010 	{ LOSTFOUNDINO, sizeof(struct direct), DT_DIR, 1, "." },
1011 	{ UFS_ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
1012 	{ 0, DIRBLKSIZ, 0, 0, 0 },
1013 };
1014 struct odirect olost_found_dir[] = {
1015 	{ LOSTFOUNDINO, sizeof(struct direct), 1, "." },
1016 	{ UFS_ROOTINO, sizeof(struct direct), 2, ".." },
1017 	{ 0, DIRBLKSIZ, 0, 0 },
1018 };
1019 #endif
1020 
1021 static void copy_dir(struct direct *, struct direct *);
1022 
1023 int
1024 fsinit(const struct timeval *tv, mode_t mfsmode, uid_t mfsuid, gid_t mfsgid)
1025 {
1026 	union dinode node;
1027 	int i;
1028 	int qblocks = 0;
1029 	int qinos = 0;
1030 	uint8_t q2h_hash_shift;
1031 	uint16_t q2h_hash_mask;
1032 #ifdef LOSTDIR
1033 	int dirblksiz = DIRBLKSIZ;
1034 	if (isappleufs)
1035 		dirblksiz = APPLEUFS_DIRBLKSIZ;
1036 	int nextino = LOSTFOUNDINO+1;
1037 #else
1038 	int nextino = UFS_ROOTINO+1;
1039 #endif
1040 
1041 	/*
1042 	 * initialize the node
1043 	 */
1044 
1045 #ifdef LOSTDIR
1046 	/*
1047 	 * create the lost+found directory
1048 	 */
1049 	memset(&node, 0, sizeof(node));
1050 	if (Oflag == 0) {
1051 		(void)makedir((struct direct *)olost_found_dir, 2);
1052 		for (i = dirblksiz; i < sblock.fs_bsize; i += dirblksiz)
1053 			copy_dir((struct direct*)&olost_found_dir[2],
1054 				(struct direct*)&buf[i]);
1055 	} else {
1056 		(void)makedir(lost_found_dir, 2);
1057 		for (i = dirblksiz; i < sblock.fs_bsize; i += dirblksiz)
1058 			copy_dir(&lost_found_dir[2], (struct direct*)&buf[i]);
1059 	}
1060 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
1061 		node.dp1.di_atime = tv->tv_sec;
1062 		node.dp1.di_atimensec = tv->tv_usec * 1000;
1063 		node.dp1.di_mtime = tv->tv_sec;
1064 		node.dp1.di_mtimensec = tv->tv_usec * 1000;
1065 		node.dp1.di_ctime = tv->tv_sec;
1066 		node.dp1.di_ctimensec = tv->tv_usec * 1000;
1067 		node.dp1.di_mode = IFDIR | UMASK;
1068 		node.dp1.di_nlink = 2;
1069 		node.dp1.di_size = sblock.fs_bsize;
1070 		node.dp1.di_db[0] = alloc(node.dp1.di_size, node.dp1.di_mode);
1071 		if (node.dp1.di_db[0] == 0)
1072 			return (0);
1073 		node.dp1.di_blocks = btodb(ffs_fragroundup(&sblock,
1074 		    node.dp1.di_size));
1075 		qblocks += node.dp1.di_blocks;
1076 		node.dp1.di_uid = geteuid();
1077 		node.dp1.di_gid = getegid();
1078 		wtfs(FFS_FSBTODB(&sblock, node.dp1.di_db[0]), node.dp1.di_size,
1079 		    buf);
1080 	} else {
1081 		node.dp2.di_atime = tv->tv_sec;
1082 		node.dp2.di_atimensec = tv->tv_usec * 1000;
1083 		node.dp2.di_mtime = tv->tv_sec;
1084 		node.dp2.di_mtimensec = tv->tv_usec * 1000;
1085 		node.dp2.di_ctime = tv->tv_sec;
1086 		node.dp2.di_ctimensec = tv->tv_usec * 1000;
1087 		node.dp2.di_birthtime = tv->tv_sec;
1088 		node.dp2.di_birthnsec = tv->tv_usec * 1000;
1089 		node.dp2.di_mode = IFDIR | UMASK;
1090 		node.dp2.di_nlink = 2;
1091 		node.dp2.di_size = sblock.fs_bsize;
1092 		node.dp2.di_db[0] = alloc(node.dp2.di_size, node.dp2.di_mode);
1093 		if (node.dp2.di_db[0] == 0)
1094 			return (0);
1095 		node.dp2.di_blocks = btodb(ffs_fragroundup(&sblock,
1096 		    node.dp2.di_size));
1097 		qblocks += node.dp2.di_blocks;
1098 		node.dp2.di_uid = geteuid();
1099 		node.dp2.di_gid = getegid();
1100 		wtfs(FFS_FSBTODB(&sblock, node.dp2.di_db[0]), node.dp2.di_size,
1101 		    buf);
1102 	}
1103 	qinos++;
1104 	iput(&node, LOSTFOUNDINO);
1105 #endif
1106 	/*
1107 	 * create the root directory
1108 	 */
1109 	memset(&node, 0, sizeof(node));
1110 	if (Oflag <= 1) {
1111 		if (mfs) {
1112 			node.dp1.di_mode = IFDIR | mfsmode;
1113 			node.dp1.di_uid = mfsuid;
1114 			node.dp1.di_gid = mfsgid;
1115 		} else {
1116 			node.dp1.di_mode = IFDIR | UMASK;
1117 			node.dp1.di_uid = geteuid();
1118 			node.dp1.di_gid = getegid();
1119 		}
1120 		node.dp1.di_nlink = PREDEFDIR;
1121 		if (Oflag == 0)
1122 			node.dp1.di_size = makedir((struct direct *)oroot_dir,
1123 			    PREDEFDIR);
1124 		else
1125 			node.dp1.di_size = makedir(root_dir, PREDEFDIR);
1126 		node.dp1.di_db[0] = alloc(sblock.fs_fsize, node.dp1.di_mode);
1127 		if (node.dp1.di_db[0] == 0)
1128 			return (0);
1129 		node.dp1.di_blocks = btodb(ffs_fragroundup(&sblock,
1130 		    node.dp1.di_size));
1131 		qblocks += node.dp1.di_blocks;
1132 		wtfs(FFS_FSBTODB(&sblock, node.dp1.di_db[0]), sblock.fs_fsize, &buf);
1133 	} else {
1134 		if (mfs) {
1135 			node.dp2.di_mode = IFDIR | mfsmode;
1136 			node.dp2.di_uid = mfsuid;
1137 			node.dp2.di_gid = mfsgid;
1138 		} else {
1139 			node.dp2.di_mode = IFDIR | UMASK;
1140 			node.dp2.di_uid = geteuid();
1141 			node.dp2.di_gid = getegid();
1142 		}
1143 		node.dp2.di_atime = tv->tv_sec;
1144 		node.dp2.di_atimensec = tv->tv_usec * 1000;
1145 		node.dp2.di_mtime = tv->tv_sec;
1146 		node.dp2.di_mtimensec = tv->tv_usec * 1000;
1147 		node.dp2.di_ctime = tv->tv_sec;
1148 		node.dp2.di_ctimensec = tv->tv_usec * 1000;
1149 		node.dp2.di_birthtime = tv->tv_sec;
1150 		node.dp2.di_birthnsec = tv->tv_usec * 1000;
1151 		node.dp2.di_nlink = PREDEFDIR;
1152 		node.dp2.di_size = makedir(root_dir, PREDEFDIR);
1153 		node.dp2.di_db[0] = alloc(sblock.fs_fsize, node.dp2.di_mode);
1154 		if (node.dp2.di_db[0] == 0)
1155 			return (0);
1156 		node.dp2.di_blocks = btodb(ffs_fragroundup(&sblock,
1157 		    node.dp2.di_size));
1158 		qblocks += node.dp2.di_blocks;
1159 		wtfs(FFS_FSBTODB(&sblock, node.dp2.di_db[0]), sblock.fs_fsize, &buf);
1160 	}
1161 	qinos++;
1162 	iput(&node, UFS_ROOTINO);
1163 	/*
1164 	 * compute the size of the hash table
1165 	 * We know the smallest block size is 4k, so we can use 2k
1166 	 * for the hash table; as an entry is 8 bytes we can store
1167 	 * 256 entries. So let start q2h_hash_shift at 8
1168 	 */
1169 	for (q2h_hash_shift = 8;
1170 	    q2h_hash_shift < 15;
1171 	    q2h_hash_shift++) {
1172 		if ((sizeof(uint64_t) << (q2h_hash_shift + 1)) +
1173 		    sizeof(struct quota2_header) > (u_int)sblock.fs_bsize)
1174 			break;
1175 	}
1176 	q2h_hash_mask = (1 << q2h_hash_shift) - 1;
1177 	for (i = 0; i < MAXQUOTAS; i++) {
1178 		struct quota2_header *q2h;
1179 		struct quota2_entry *q2e;
1180 		uint64_t offset;
1181 		uid_t uid = (i == USRQUOTA ? geteuid() : getegid());
1182 
1183 		if ((quotas & FS_Q2_DO_TYPE(i)) == 0)
1184 			continue;
1185 		quota2_create_blk0(sblock.fs_bsize, &buf, q2h_hash_shift,
1186 		    i, needswap);
1187 		/* grab an entry from header for root dir */
1188 		q2h = &buf.q2h;
1189 		offset = ufs_rw64(q2h->q2h_free, needswap);
1190 		q2e = (void *)((char *)&buf + offset);
1191 		q2h->q2h_free = q2e->q2e_next;
1192 		memcpy(q2e, &q2h->q2h_defentry, sizeof(*q2e));
1193 		q2e->q2e_uid = ufs_rw32(uid, needswap);
1194 		q2e->q2e_val[QL_BLOCK].q2v_cur = ufs_rw64(qblocks, needswap);
1195 		q2e->q2e_val[QL_FILE].q2v_cur = ufs_rw64(qinos, needswap);
1196 		/* add to the hash entry */
1197 		q2e->q2e_next = q2h->q2h_entries[uid & q2h_hash_mask];
1198 		q2h->q2h_entries[uid & q2h_hash_mask] =
1199 		    ufs_rw64(offset, needswap);
1200 
1201 		memset(&node, 0, sizeof(node));
1202 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
1203 			node.dp1.di_atime = tv->tv_sec;
1204 			node.dp1.di_atimensec = tv->tv_usec * 1000;
1205 			node.dp1.di_mtime = tv->tv_sec;
1206 			node.dp1.di_mtimensec = tv->tv_usec * 1000;
1207 			node.dp1.di_ctime = tv->tv_sec;
1208 			node.dp1.di_ctimensec = tv->tv_usec * 1000;
1209 			node.dp1.di_mode = IFREG;
1210 			node.dp1.di_nlink = 1;
1211 			node.dp1.di_size = sblock.fs_bsize;
1212 			node.dp1.di_db[0] =
1213 			    alloc(node.dp1.di_size, node.dp1.di_mode);
1214 			if (node.dp1.di_db[0] == 0)
1215 				return (0);
1216 			node.dp1.di_blocks = btodb(ffs_fragroundup(&sblock,
1217 			    node.dp1.di_size));
1218 			node.dp1.di_uid = geteuid();
1219 			node.dp1.di_gid = getegid();
1220 			wtfs(FFS_FSBTODB(&sblock, node.dp1.di_db[0]),
1221 			     node.dp1.di_size, &buf);
1222 		} else {
1223 			node.dp2.di_atime = tv->tv_sec;
1224 			node.dp2.di_atimensec = tv->tv_usec * 1000;
1225 			node.dp2.di_mtime = tv->tv_sec;
1226 			node.dp2.di_mtimensec = tv->tv_usec * 1000;
1227 			node.dp2.di_ctime = tv->tv_sec;
1228 			node.dp2.di_ctimensec = tv->tv_usec * 1000;
1229 			node.dp2.di_birthtime = tv->tv_sec;
1230 			node.dp2.di_birthnsec = tv->tv_usec * 1000;
1231 			node.dp2.di_mode = IFREG;
1232 			node.dp2.di_nlink = 1;
1233 			node.dp2.di_size = sblock.fs_bsize;
1234 			node.dp2.di_db[0] =
1235 			    alloc(node.dp2.di_size, node.dp2.di_mode);
1236 			if (node.dp2.di_db[0] == 0)
1237 				return (0);
1238 			node.dp2.di_blocks = btodb(ffs_fragroundup(&sblock,
1239 			    node.dp2.di_size));
1240 			node.dp2.di_uid = geteuid();
1241 			node.dp2.di_gid = getegid();
1242 			wtfs(FFS_FSBTODB(&sblock, node.dp2.di_db[0]),
1243 			    node.dp2.di_size, &buf);
1244 		}
1245 		iput(&node, nextino);
1246 		sblock.fs_quotafile[i] = nextino;
1247 		nextino++;
1248 	}
1249 	return (1);
1250 }
1251 
1252 /*
1253  * construct a set of directory entries in "buf".
1254  * return size of directory.
1255  */
1256 int
1257 makedir(struct direct *protodir, int entries)
1258 {
1259 	char *cp;
1260 	int i, spcleft;
1261 	int dirblksiz = UFS_DIRBLKSIZ;
1262 	if (isappleufs)
1263 		dirblksiz = APPLEUFS_DIRBLKSIZ;
1264 
1265 	memset(&buf, 0, UFS_DIRBLKSIZ);
1266 	spcleft = dirblksiz;
1267 	for (cp = buf.data, i = 0; i < entries - 1; i++) {
1268 		protodir[i].d_reclen = UFS_DIRSIZ(Oflag == 0, &protodir[i], 0);
1269 		copy_dir(&protodir[i], (struct direct*)cp);
1270 		cp += protodir[i].d_reclen;
1271 		spcleft -= protodir[i].d_reclen;
1272 	}
1273 	protodir[i].d_reclen = spcleft;
1274 	copy_dir(&protodir[i], (struct direct*)cp);
1275 	return (dirblksiz);
1276 }
1277 
1278 /*
1279  * allocate a block or frag
1280  */
1281 daddr_t
1282 alloc(int size, int mode)
1283 {
1284 	int i, frag;
1285 	daddr_t d, blkno;
1286 
1287 	rdfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
1288 	/* fs -> host byte order */
1289 	if (needswap)
1290 		ffs_cg_swap(&acg, &acg, &sblock);
1291 	if (acg.cg_magic != CG_MAGIC) {
1292 		printf("cg 0: bad magic number\n");
1293 		return (0);
1294 	}
1295 	if (acg.cg_cs.cs_nbfree == 0) {
1296 		printf("first cylinder group ran out of space\n");
1297 		return (0);
1298 	}
1299 	for (d = 0; d < acg.cg_ndblk; d += sblock.fs_frag)
1300 		if (isblock(&sblock, cg_blksfree(&acg, 0),
1301 		    d >> sblock.fs_fragshift))
1302 			goto goth;
1303 	printf("internal error: can't find block in cyl 0\n");
1304 	return (0);
1305 goth:
1306 	blkno = ffs_fragstoblks(&sblock, d);
1307 	clrblock(&sblock, cg_blksfree(&acg, 0), blkno);
1308 	if (sblock.fs_contigsumsize > 0)
1309 		clrbit(cg_clustersfree(&acg, 0), blkno);
1310 	acg.cg_cs.cs_nbfree--;
1311 	sblock.fs_cstotal.cs_nbfree--;
1312 	fscs_0->cs_nbfree--;
1313 	if (mode & IFDIR) {
1314 		acg.cg_cs.cs_ndir++;
1315 		sblock.fs_cstotal.cs_ndir++;
1316 		fscs_0->cs_ndir++;
1317 	}
1318 	if (Oflag <= 1) {
1319 		int cn = old_cbtocylno(&sblock, d);
1320 		old_cg_blktot(&acg, 0)[cn]--;
1321 		old_cg_blks(&sblock, &acg,
1322 		    cn, 0)[old_cbtorpos(&sblock, d)]--;
1323 	}
1324 	if (size != sblock.fs_bsize) {
1325 		frag = howmany(size, sblock.fs_fsize);
1326 		fscs_0->cs_nffree += sblock.fs_frag - frag;
1327 		sblock.fs_cstotal.cs_nffree += sblock.fs_frag - frag;
1328 		acg.cg_cs.cs_nffree += sblock.fs_frag - frag;
1329 		acg.cg_frsum[sblock.fs_frag - frag]++;
1330 		for (i = frag; i < sblock.fs_frag; i++)
1331 			setbit(cg_blksfree(&acg, 0), d + i);
1332 	}
1333 	/* host -> fs byte order */
1334 	if (needswap)
1335 		ffs_cg_swap(&acg, &acg, &sblock);
1336 	wtfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
1337 	return (d);
1338 }
1339 
1340 /*
1341  * Allocate an inode on the disk
1342  */
1343 static void
1344 iput(union dinode *ip, ino_t ino)
1345 {
1346 	daddr_t d;
1347 	int i;
1348 	struct ufs1_dinode *dp1;
1349 	struct ufs2_dinode *dp2;
1350 
1351 	rdfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
1352 	/* fs -> host byte order */
1353 	if (needswap)
1354 		ffs_cg_swap(&acg, &acg, &sblock);
1355 	if (acg.cg_magic != CG_MAGIC) {
1356 		printf("cg 0: bad magic number\n");
1357 		fserr(31);
1358 	}
1359 	acg.cg_cs.cs_nifree--;
1360 	setbit(cg_inosused(&acg, 0), ino);
1361 	/* host -> fs byte order */
1362 	if (needswap)
1363 		ffs_cg_swap(&acg, &acg, &sblock);
1364 	wtfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
1365 	sblock.fs_cstotal.cs_nifree--;
1366 	fscs_0->cs_nifree--;
1367 	if (ino >= (ino_t)(sblock.fs_ipg * sblock.fs_ncg)) {
1368 		printf("fsinit: inode value out of range (%llu).\n",
1369 		    (unsigned long long)ino);
1370 		fserr(32);
1371 	}
1372 	d = FFS_FSBTODB(&sblock, ino_to_fsba(&sblock, ino));
1373 	rdfs(d, sblock.fs_bsize, (char *)iobuf);
1374 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
1375 		dp1 = (struct ufs1_dinode *)iobuf;
1376 		dp1 += ino_to_fsbo(&sblock, ino);
1377 		if (needswap) {
1378 			ffs_dinode1_swap(&ip->dp1, dp1);
1379 			/* ffs_dinode1_swap() doesn't swap blocks addrs */
1380 			for (i=0; i<UFS_NDADDR; i++)
1381 			    dp1->di_db[i] = bswap32(ip->dp1.di_db[i]);
1382 			for (i=0; i<UFS_NIADDR; i++)
1383 			    dp1->di_ib[i] = bswap32(ip->dp1.di_ib[i]);
1384 		} else
1385 			*dp1 = ip->dp1;
1386 		dp1->di_gen = arc4random() & INT32_MAX;
1387 	} else {
1388 		dp2 = (struct ufs2_dinode *)iobuf;
1389 		dp2 += ino_to_fsbo(&sblock, ino);
1390 		if (needswap) {
1391 			ffs_dinode2_swap(&ip->dp2, dp2);
1392 			for (i=0; i<UFS_NDADDR; i++)
1393 			    dp2->di_db[i] = bswap64(ip->dp2.di_db[i]);
1394 			for (i=0; i<UFS_NIADDR; i++)
1395 			    dp2->di_ib[i] = bswap64(ip->dp2.di_ib[i]);
1396 		} else
1397 			*dp2 = ip->dp2;
1398 		dp2->di_gen = arc4random() & INT32_MAX;
1399 	}
1400 	wtfs(d, sblock.fs_bsize, iobuf);
1401 }
1402 
1403 /*
1404  * read a block from the file system
1405  */
1406 void
1407 rdfs(daddr_t bno, int size, void *bf)
1408 {
1409 	int n;
1410 	off_t offset;
1411 
1412 #ifdef MFS
1413 	if (mfs) {
1414 		if (Nflag)
1415 			memset(bf, 0, size);
1416 		else
1417 			memmove(bf, membase + bno * sectorsize, size);
1418 		return;
1419 	}
1420 #endif
1421 	offset = bno;
1422 	n = pread(fsi, bf, size, offset * sectorsize);
1423 	if (n != size) {
1424 		printf("rdfs: read error for sector %lld: %s\n",
1425 		    (long long)bno, strerror(errno));
1426 		exit(34);
1427 	}
1428 }
1429 
1430 /*
1431  * write a block to the file system
1432  */
1433 void
1434 wtfs(daddr_t bno, int size, void *bf)
1435 {
1436 	int n;
1437 	off_t offset;
1438 
1439 	if (Nflag)
1440 		return;
1441 #ifdef MFS
1442 	if (mfs) {
1443 		memmove(membase + bno * sectorsize, bf, size);
1444 		return;
1445 	}
1446 #endif
1447 	offset = bno;
1448 	n = pwrite(fso, bf, size, offset * sectorsize);
1449 	if (n != size) {
1450 		printf("wtfs: write error for sector %lld: %s\n",
1451 		    (long long)bno, strerror(errno));
1452 		exit(36);
1453 	}
1454 }
1455 
1456 /*
1457  * check if a block is available
1458  */
1459 int
1460 isblock(struct fs *fs, unsigned char *cp, int h)
1461 {
1462 	unsigned char mask;
1463 
1464 	switch (fs->fs_fragshift) {
1465 	case 3:
1466 		return (cp[h] == 0xff);
1467 	case 2:
1468 		mask = 0x0f << ((h & 0x1) << 2);
1469 		return ((cp[h >> 1] & mask) == mask);
1470 	case 1:
1471 		mask = 0x03 << ((h & 0x3) << 1);
1472 		return ((cp[h >> 2] & mask) == mask);
1473 	case 0:
1474 		mask = 0x01 << (h & 0x7);
1475 		return ((cp[h >> 3] & mask) == mask);
1476 	default:
1477 #ifdef STANDALONE
1478 		printf("isblock bad fs_fragshift %d\n", fs->fs_fragshift);
1479 #else
1480 		fprintf(stderr, "isblock bad fs_fragshift %d\n",
1481 		    fs->fs_fragshift);
1482 #endif
1483 		return (0);
1484 	}
1485 }
1486 
1487 /*
1488  * take a block out of the map
1489  */
1490 void
1491 clrblock(struct fs *fs, unsigned char *cp, int h)
1492 {
1493 	switch ((fs)->fs_fragshift) {
1494 	case 3:
1495 		cp[h] = 0;
1496 		return;
1497 	case 2:
1498 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
1499 		return;
1500 	case 1:
1501 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
1502 		return;
1503 	case 0:
1504 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
1505 		return;
1506 	default:
1507 #ifdef STANDALONE
1508 		printf("clrblock bad fs_fragshift %d\n", fs->fs_fragshift);
1509 #else
1510 		fprintf(stderr, "clrblock bad fs_fragshift %d\n",
1511 		    fs->fs_fragshift);
1512 #endif
1513 		return;
1514 	}
1515 }
1516 
1517 /*
1518  * put a block into the map
1519  */
1520 void
1521 setblock(struct fs *fs, unsigned char *cp, int h)
1522 {
1523 	switch (fs->fs_fragshift) {
1524 	case 3:
1525 		cp[h] = 0xff;
1526 		return;
1527 	case 2:
1528 		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
1529 		return;
1530 	case 1:
1531 		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
1532 		return;
1533 	case 0:
1534 		cp[h >> 3] |= (0x01 << (h & 0x7));
1535 		return;
1536 	default:
1537 #ifdef STANDALONE
1538 		printf("setblock bad fs_frag %d\n", fs->fs_fragshift);
1539 #else
1540 		fprintf(stderr, "setblock bad fs_fragshift %d\n",
1541 		    fs->fs_fragshift);
1542 #endif
1543 		return;
1544 	}
1545 }
1546 
1547 /* copy a direntry to a buffer, in fs byte order */
1548 static void
1549 copy_dir(struct direct *dir, struct direct *dbuf)
1550 {
1551 	memcpy(dbuf, dir, UFS_DIRSIZ(Oflag == 0, dir, 0));
1552 	if (needswap) {
1553 		dbuf->d_ino = bswap32(dir->d_ino);
1554 		dbuf->d_reclen = bswap16(dir->d_reclen);
1555 		if (Oflag == 0)
1556 			((struct odirect*)dbuf)->d_namlen =
1557 				bswap16(((struct odirect*)dir)->d_namlen);
1558 	}
1559 }
1560 
1561 static int
1562 ilog2(int val)
1563 {
1564 	u_int n;
1565 
1566 	for (n = 0; n < sizeof(n) * CHAR_BIT; n++)
1567 		if (1 << n == val)
1568 			return (n);
1569 	errx(1, "ilog2: %d is not a power of 2\n", val);
1570 }
1571 
1572 static void
1573 zap_old_sblock(int sblkoff)
1574 {
1575 	static int cg0_data;
1576 	uint32_t oldfs[SBLOCKSIZE / 4];
1577 	static const struct fsm {
1578 		uint32_t	offset;
1579 		uint32_t	magic;
1580 		uint32_t	mask;
1581 	} fs_magics[] = {
1582 		{offsetof(struct fs, fs_magic)/4, FS_UFS1_MAGIC, ~0u},
1583 		{offsetof(struct fs, fs_magic)/4, FS_UFS2_MAGIC, ~0u},
1584 		{0, 0x70162, ~0u},		/* LFS_MAGIC */
1585 		{14, 0xef53, 0xffff},		/* EXT2FS (little) */
1586 		{14, 0xef530000, 0xffff0000},	/* EXT2FS (big) */
1587 		{.offset = ~0u},
1588 	};
1589 	const struct fsm *fsm;
1590 
1591 	if (Nflag)
1592 		return;
1593 
1594 	if (sblkoff == 0)	/* Why did UFS2 add support for this?  sigh. */
1595 		return;
1596 
1597 	if (cg0_data == 0)
1598 		/* For FFSv1 this could include all the inodes. */
1599 		cg0_data = cgsblock(&sblock, 0) * sblock.fs_fsize + iobufsize;
1600 
1601 	/* Ignore anything that is beyond our filesystem */
1602 	if ((sblkoff + SBLOCKSIZE)/sectorsize >= fssize)
1603 		return;
1604 	/* Zero anything inside our filesystem... */
1605 	if (sblkoff >= sblock.fs_sblockloc) {
1606 		/* ...unless we will write that area anyway */
1607 		if (sblkoff >= cg0_data)
1608 			wtfs(sblkoff / sectorsize,
1609 			    roundup(sizeof sblock, sectorsize), iobuf);
1610 		return;
1611 	}
1612 
1613 	/* The sector might contain boot code, so we must validate it */
1614 	rdfs(sblkoff/sectorsize, sizeof oldfs, &oldfs);
1615 	for (fsm = fs_magics; ; fsm++) {
1616 		uint32_t v;
1617 		if (fsm->mask == 0)
1618 			return;
1619 		v = oldfs[fsm->offset];
1620 		if ((v & fsm->mask) == fsm->magic ||
1621 		    (bswap32(v) & fsm->mask) == fsm->magic)
1622 			break;
1623 	}
1624 
1625 	/* Just zap the magic number */
1626 	oldfs[fsm->offset] = 0;
1627 	wtfs(sblkoff/sectorsize, sizeof oldfs, &oldfs);
1628 }
1629 
1630 
1631 #ifdef MFS
1632 /*
1633  * Internal version of malloc that trims the requested size if not enough
1634  * memory is available.
1635  */
1636 static void *
1637 mkfs_malloc(size_t size)
1638 {
1639 	u_long pgsz;
1640 	caddr_t *memory, *extra;
1641 	size_t exsize = 128 * 1024;
1642 
1643 	if (size == 0)
1644 		return (NULL);
1645 
1646 	pgsz = getpagesize() - 1;
1647 	size = (size + pgsz) &~ pgsz;
1648 
1649 	/* try to map requested size */
1650 	memory = mmap(0, size, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
1651 	    -1, 0);
1652 	if (memory == MAP_FAILED)
1653 		return NULL;
1654 
1655 	/* try to map something extra */
1656 	extra = mmap(0, exsize, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
1657 	    -1, 0);
1658 	munmap(extra, exsize);
1659 
1660 	/* if extra memory couldn't be mapped, reduce original request accordingly */
1661 	if (extra == MAP_FAILED) {
1662 		munmap(memory, size);
1663 		size -= exsize;
1664 		memory = mmap(0, size, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
1665 		    -1, 0);
1666 		if (memory == MAP_FAILED)
1667 			return NULL;
1668 	}
1669 
1670 	return memory;
1671 }
1672 #endif	/* MFS */
1673