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mkfs.c revision 1.119
      1 /*	$NetBSD: mkfs.c,v 1.119 2013/06/23 07:28:36 dholland 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 1.119 2013/06/23 07:28:36 dholland 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 pad[SBLOCKSIZE];
    135 } fsun;
    136 #define	sblock	fsun.fs
    137 
    138 struct	csum *fscs_0;		/* first block of cylinder summaries */
    139 struct	csum *fscs_next;	/* place for next summary */
    140 struct	csum *fscs_end;		/* end of summary buffer */
    141 struct	csum *fscs_reset;	/* place for next summary after write */
    142 uint	fs_csaddr;		/* fragment number to write to */
    143 
    144 union {
    145 	struct cg cg;
    146 	char pad[MAXBSIZE];
    147 } cgun;
    148 #define	acg	cgun.cg
    149 
    150 #define DIP(dp, field) \
    151 	((sblock.fs_magic == FS_UFS1_MAGIC) ? \
    152 	(dp)->dp1.di_##field : (dp)->dp2.di_##field)
    153 
    154 #define EXT2FS_SBOFF	1024	/* XXX: SBOFF in <ufs/ext2fs/ext2fs.h> */
    155 
    156 char *iobuf;
    157 int iobufsize;			/* size to end of 2nd inode block */
    158 int iobuf_memsize;		/* Actual buffer size */
    159 
    160 int	fsi, fso;
    161 
    162 static void
    163 fserr(int num)
    164 {
    165 #ifdef GARBAGE
    166 	extern int Gflag;
    167 
    168 	if (Gflag)
    169 		return;
    170 #endif
    171 	exit(num);
    172 }
    173 
    174 void
    175 mkfs(const char *fsys, int fi, int fo,
    176     mode_t mfsmode, uid_t mfsuid, gid_t mfsgid)
    177 {
    178 	uint fragsperinodeblk, ncg, u;
    179 	uint cgzero;
    180 	uint64_t inodeblks, cgall;
    181 	int32_t cylno, i, csfrags;
    182 	int inodes_per_cg;
    183 	struct timeval tv;
    184 	long long sizepb;
    185 	int len, col, delta, fld_width, max_cols;
    186 	struct winsize winsize;
    187 
    188 #ifndef STANDALONE
    189 	gettimeofday(&tv, NULL);
    190 #endif
    191 #ifdef MFS
    192 	if (mfs && !Nflag) {
    193 		if ((membase = mkfs_malloc(fssize * sectorsize)) == NULL)
    194 			exit(12);
    195 	}
    196 #endif
    197 	fsi = fi;
    198 	fso = fo;
    199 	if (Oflag == 0) {
    200 		sblock.fs_old_inodefmt = FS_42INODEFMT;
    201 		sblock.fs_maxsymlinklen = 0;
    202 		sblock.fs_old_flags = 0;
    203 	} else {
    204 		sblock.fs_old_inodefmt = FS_44INODEFMT;
    205 		sblock.fs_maxsymlinklen = (Oflag == 1 ? UFS1_MAXSYMLINKLEN :
    206 		    UFS2_MAXSYMLINKLEN);
    207 		sblock.fs_old_flags = FS_FLAGS_UPDATED;
    208 		if (isappleufs)
    209 			sblock.fs_old_flags = 0;
    210 		sblock.fs_flags = 0;
    211 	}
    212 
    213 	/*
    214 	 * collect and verify the filesystem density info
    215 	 */
    216 	sblock.fs_avgfilesize = avgfilesize;
    217 	sblock.fs_avgfpdir = avgfpdir;
    218 	if (sblock.fs_avgfilesize <= 0) {
    219 		printf("illegal expected average file size %d\n",
    220 		    sblock.fs_avgfilesize);
    221 		fserr(14);
    222 	}
    223 	if (sblock.fs_avgfpdir <= 0) {
    224 		printf("illegal expected number of files per directory %d\n",
    225 		    sblock.fs_avgfpdir);
    226 		fserr(15);
    227 	}
    228 	/*
    229 	 * collect and verify the block and fragment sizes
    230 	 */
    231 	sblock.fs_bsize = bsize;
    232 	sblock.fs_fsize = fsize;
    233 	if (!powerof2(sblock.fs_bsize)) {
    234 		printf("block size must be a power of 2, not %d\n",
    235 		    sblock.fs_bsize);
    236 		fserr(16);
    237 	}
    238 	if (!powerof2(sblock.fs_fsize)) {
    239 		printf("fragment size must be a power of 2, not %d\n",
    240 		    sblock.fs_fsize);
    241 		fserr(17);
    242 	}
    243 	if (sblock.fs_fsize < sectorsize) {
    244 		printf("fragment size %d is too small, minimum is %d\n",
    245 		    sblock.fs_fsize, sectorsize);
    246 		fserr(18);
    247 	}
    248 	if (sblock.fs_bsize < MINBSIZE) {
    249 		printf("block size %d is too small, minimum is %d\n",
    250 		    sblock.fs_bsize, MINBSIZE);
    251 		fserr(19);
    252 	}
    253 	if (sblock.fs_bsize > MAXBSIZE) {
    254 		printf("block size %d is too large, maximum is %d\n",
    255 		    sblock.fs_bsize, MAXBSIZE);
    256 		fserr(19);
    257 	}
    258 	if (sblock.fs_bsize < sblock.fs_fsize) {
    259 		printf("block size (%d) cannot be smaller than fragment size (%d)\n",
    260 		    sblock.fs_bsize, sblock.fs_fsize);
    261 		fserr(20);
    262 	}
    263 
    264 	if (maxbsize < bsize || !powerof2(maxbsize)) {
    265 		sblock.fs_maxbsize = sblock.fs_bsize;
    266 	} else if (sblock.fs_maxbsize > FS_MAXCONTIG * sblock.fs_bsize) {
    267 		sblock.fs_maxbsize = FS_MAXCONTIG * sblock.fs_bsize;
    268 	} else {
    269 		sblock.fs_maxbsize = maxbsize;
    270 	}
    271 	sblock.fs_maxcontig = maxcontig;
    272 	if (sblock.fs_maxcontig < sblock.fs_maxbsize / sblock.fs_bsize) {
    273 		sblock.fs_maxcontig = sblock.fs_maxbsize / sblock.fs_bsize;
    274 		if (verbosity > 0)
    275 			printf("Maxcontig raised to %d\n", sblock.fs_maxbsize);
    276 	}
    277 	if (sblock.fs_maxcontig > 1)
    278 		sblock.fs_contigsumsize = MIN(sblock.fs_maxcontig,FS_MAXCONTIG);
    279 
    280 	sblock.fs_bmask = ~(sblock.fs_bsize - 1);
    281 	sblock.fs_fmask = ~(sblock.fs_fsize - 1);
    282 	sblock.fs_qbmask = ~sblock.fs_bmask;
    283 	sblock.fs_qfmask = ~sblock.fs_fmask;
    284 	for (sblock.fs_bshift = 0, i = sblock.fs_bsize; i > 1; i >>= 1)
    285 		sblock.fs_bshift++;
    286 	for (sblock.fs_fshift = 0, i = sblock.fs_fsize; i > 1; i >>= 1)
    287 		sblock.fs_fshift++;
    288 	sblock.fs_frag = ffs_numfrags(&sblock, sblock.fs_bsize);
    289 	for (sblock.fs_fragshift = 0, i = sblock.fs_frag; i > 1; i >>= 1)
    290 		sblock.fs_fragshift++;
    291 	if (sblock.fs_frag > MAXFRAG) {
    292 		printf("fragment size %d is too small, "
    293 			"minimum with block size %d is %d\n",
    294 		    sblock.fs_fsize, sblock.fs_bsize,
    295 		    sblock.fs_bsize / MAXFRAG);
    296 		fserr(21);
    297 	}
    298 	sblock.fs_fsbtodb = ilog2(sblock.fs_fsize / sectorsize);
    299 	sblock.fs_size = FFS_DBTOFSB(&sblock, fssize);
    300 	if (Oflag <= 1) {
    301 		if ((uint64_t)sblock.fs_size >= 1ull << 31) {
    302 			printf("Too many fragments (0x%" PRIx64
    303 			    ") for a FFSv1 filesystem\n", sblock.fs_size);
    304 			fserr(22);
    305 		}
    306 		sblock.fs_magic = FS_UFS1_MAGIC;
    307 		sblock.fs_sblockloc = SBLOCK_UFS1;
    308 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int32_t);
    309 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs1_dinode);
    310 		sblock.fs_old_cgoffset = 0;
    311 		sblock.fs_old_cgmask = 0xffffffff;
    312 		sblock.fs_old_size = sblock.fs_size;
    313 		sblock.fs_old_rotdelay = 0;
    314 		sblock.fs_old_rps = 60;
    315 		sblock.fs_old_nspf = sblock.fs_fsize / sectorsize;
    316 		sblock.fs_old_cpg = 1;
    317 		sblock.fs_old_interleave = 1;
    318 		sblock.fs_old_trackskew = 0;
    319 		sblock.fs_old_cpc = 0;
    320 		sblock.fs_old_postblformat = FS_DYNAMICPOSTBLFMT;
    321 		sblock.fs_old_nrpos = 1;
    322 	} else {
    323 		sblock.fs_magic = FS_UFS2_MAGIC;
    324 		sblock.fs_sblockloc = SBLOCK_UFS2;
    325 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int64_t);
    326 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs2_dinode);
    327 	}
    328 
    329 	sblock.fs_sblkno =
    330 	    roundup(howmany(sblock.fs_sblockloc + SBLOCKSIZE, sblock.fs_fsize),
    331 		sblock.fs_frag);
    332 	sblock.fs_cblkno = (daddr_t)(sblock.fs_sblkno +
    333 	    roundup(howmany(SBLOCKSIZE, sblock.fs_fsize), sblock.fs_frag));
    334 	sblock.fs_iblkno = sblock.fs_cblkno + sblock.fs_frag;
    335 	sblock.fs_maxfilesize = sblock.fs_bsize * UFS_NDADDR - 1;
    336 	for (sizepb = sblock.fs_bsize, i = 0; i < UFS_NIADDR; i++) {
    337 		sizepb *= FFS_NINDIR(&sblock);
    338 		sblock.fs_maxfilesize += sizepb;
    339 	}
    340 
    341 	/*
    342 	 * Calculate the number of blocks to put into each cylinder group.
    343 	 *
    344 	 * The cylinder group size is limited because the data structure
    345 	 * must fit into a single block.
    346 	 * We try to have as few cylinder groups as possible, with a proviso
    347 	 * that we create at least MINCYLGRPS (==4) except for small
    348 	 * filesystems.
    349 	 *
    350 	 * This algorithm works out how many blocks of inodes would be
    351 	 * needed to fill the entire volume at the specified density.
    352 	 * It then looks at how big the 'cylinder block' would have to
    353 	 * be and, assuming that it is linearly related to the number
    354 	 * of inodes and blocks how many cylinder groups are needed to
    355 	 * keep the cylinder block below the filesystem block size.
    356 	 *
    357 	 * The cylinder groups are then all created with the average size.
    358 	 *
    359 	 * Space taken by the red tape on cylinder groups other than the
    360 	 * first is ignored.
    361 	 */
    362 
    363 	/* There must be space for 1 inode block and 2 data blocks */
    364 	if (sblock.fs_size < sblock.fs_iblkno + 3 * sblock.fs_frag) {
    365 		printf("Filesystem size %lld < minimum size of %d\n",
    366 		    (long long)sblock.fs_size, sblock.fs_iblkno + 3 * sblock.fs_frag);
    367 		fserr(23);
    368 	}
    369 	if (num_inodes != 0)
    370 		inodeblks = howmany(num_inodes, FFS_INOPB(&sblock));
    371 	else {
    372 		/*
    373 		 * Calculate 'per inode block' so we can allocate less than
    374 		 * 1 fragment per inode - useful for /dev.
    375 		 */
    376 		fragsperinodeblk = MAX(ffs_numfrags(&sblock,
    377 					(uint64_t)density * FFS_INOPB(&sblock)), 1);
    378 		inodeblks = (sblock.fs_size - sblock.fs_iblkno) /
    379 			(sblock.fs_frag + fragsperinodeblk);
    380 	}
    381 	if (inodeblks == 0)
    382 		inodeblks = 1;
    383 	/* Ensure that there are at least 2 data blocks (or we fail below) */
    384 	if (inodeblks > (uint64_t)(sblock.fs_size - sblock.fs_iblkno)/sblock.fs_frag - 2)
    385 		inodeblks = (sblock.fs_size-sblock.fs_iblkno)/sblock.fs_frag-2;
    386 	/* Even UFS2 limits number of inodes to 2^31 (fs_ipg is int32_t) */
    387 	if (inodeblks * FFS_INOPB(&sblock) >= 1ull << 31)
    388 		inodeblks = ((1ull << 31) - NBBY) / FFS_INOPB(&sblock);
    389 	/*
    390 	 * See what would happen if we tried to use 1 cylinder group.
    391 	 * Assume space linear, so work out number of cylinder groups needed.
    392 	 */
    393 	cgzero = CGSIZE_IF(&sblock, 0, 0);
    394 	cgall = CGSIZE_IF(&sblock, inodeblks * FFS_INOPB(&sblock), sblock.fs_size);
    395 	ncg = howmany(cgall - cgzero, sblock.fs_bsize - cgzero);
    396 	if (ncg < MINCYLGRPS) {
    397 		/*
    398 		 * We would like to allocate MINCLYGRPS cylinder groups,
    399 		 * but for small file sytems (especially ones with a lot
    400 		 * of inodes) this is not desirable (or possible).
    401 		 */
    402 		u = sblock.fs_size / 2 / (sblock.fs_iblkno +
    403 						inodeblks * sblock.fs_frag);
    404 		if (u > ncg)
    405 			ncg = u;
    406 		if (ncg > MINCYLGRPS)
    407 			ncg = MINCYLGRPS;
    408 		if (ncg > inodeblks)
    409 			ncg = inodeblks;
    410 	}
    411 	/*
    412 	 * Put an equal number of blocks in each cylinder group.
    413 	 * Round up so we don't have more fragments in the last CG than
    414 	 * the earlier ones (does that matter?), but kill a block if the
    415 	 * CGSIZE becomes too big (only happens if there are a lot of CGs).
    416 	 */
    417 	sblock.fs_fpg = roundup(howmany(sblock.fs_size, ncg), sblock.fs_frag);
    418 	/* Round up the fragments/group so the bitmap bytes are full */
    419 	sblock.fs_fpg = roundup(sblock.fs_fpg, NBBY);
    420 	inodes_per_cg = ((inodeblks - 1) / ncg + 1) * FFS_INOPB(&sblock);
    421 
    422 	i = CGSIZE_IF(&sblock, inodes_per_cg, sblock.fs_fpg);
    423 	if (i > sblock.fs_bsize) {
    424 		sblock.fs_fpg -= (i - sblock.fs_bsize) * NBBY;
    425 		/* ... and recalculate how many cylinder groups we now need */
    426 		ncg = howmany(sblock.fs_size, sblock.fs_fpg);
    427 		inodes_per_cg = ((inodeblks - 1) / ncg + 1) * FFS_INOPB(&sblock);
    428 	}
    429 	sblock.fs_ipg = inodes_per_cg;
    430 	/* Sanity check on our sums... */
    431 	if ((int)CGSIZE(&sblock) > sblock.fs_bsize) {
    432 		printf("CGSIZE miscalculated %d > %d\n",
    433 		    (int)CGSIZE(&sblock), sblock.fs_bsize);
    434 		fserr(24);
    435 	}
    436 
    437 	sblock.fs_dblkno = sblock.fs_iblkno + sblock.fs_ipg / FFS_INOPF(&sblock);
    438 	/* Check that the last cylinder group has enough space for the inodes */
    439 	i = sblock.fs_size - sblock.fs_fpg * (ncg - 1ull);
    440 	if (i < sblock.fs_dblkno) {
    441 		/*
    442 		 * Since we make all the cylinder groups the same size, the
    443 		 * last will only be small if there are a large number of
    444 		 * cylinder groups. If we pull even a fragment from each
    445 		 * of the other groups then the last CG will be overfull.
    446 		 * So we just kill the last CG.
    447 		 */
    448 		ncg--;
    449 		sblock.fs_size -= i;
    450 	}
    451 	sblock.fs_ncg = ncg;
    452 
    453 	sblock.fs_cgsize = ffs_fragroundup(&sblock, CGSIZE(&sblock));
    454 	if (Oflag <= 1) {
    455 		sblock.fs_old_spc = sblock.fs_fpg * sblock.fs_old_nspf;
    456 		sblock.fs_old_nsect = sblock.fs_old_spc;
    457 		sblock.fs_old_npsect = sblock.fs_old_spc;
    458 		sblock.fs_old_ncyl = sblock.fs_ncg;
    459 	}
    460 
    461 	/*
    462 	 * Cylinder group summary information for each cylinder is written
    463 	 * into the first cylinder group.
    464 	 * Write this fragment by fragment, but doing the first CG last
    465 	 * (after we've taken stuff off for the structure itself and the
    466 	 * root directory.
    467 	 */
    468 	sblock.fs_csaddr = cgdmin(&sblock, 0);
    469 	sblock.fs_cssize =
    470 	    ffs_fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));
    471 	if (512 % sizeof *fscs_0)
    472 		errx(1, "cylinder group summary doesn't fit in sectors");
    473 	fscs_0 = mmap(0, 2 * sblock.fs_fsize, PROT_READ|PROT_WRITE,
    474 			MAP_ANON|MAP_PRIVATE, -1, 0);
    475 	if (fscs_0 == MAP_FAILED)
    476 		exit(39);
    477 	memset(fscs_0, 0, 2 * sblock.fs_fsize);
    478 	fs_csaddr = sblock.fs_csaddr;
    479 	fscs_next = fscs_0;
    480 	fscs_end = (void *)((char *)fscs_0 + 2 * sblock.fs_fsize);
    481 	fscs_reset = (void *)((char *)fscs_0 + sblock.fs_fsize);
    482 	/*
    483 	 * fill in remaining fields of the super block
    484 	 */
    485 	sblock.fs_sbsize = ffs_fragroundup(&sblock, sizeof(struct fs));
    486 	if (sblock.fs_sbsize > SBLOCKSIZE)
    487 		sblock.fs_sbsize = SBLOCKSIZE;
    488 	sblock.fs_minfree = minfree;
    489 	sblock.fs_maxcontig = maxcontig;
    490 	sblock.fs_maxbpg = maxbpg;
    491 	sblock.fs_optim = opt;
    492 	sblock.fs_cgrotor = 0;
    493 	sblock.fs_pendingblocks = 0;
    494 	sblock.fs_pendinginodes = 0;
    495 	sblock.fs_cstotal.cs_ndir = 0;
    496 	sblock.fs_cstotal.cs_nbfree = 0;
    497 	sblock.fs_cstotal.cs_nifree = 0;
    498 	sblock.fs_cstotal.cs_nffree = 0;
    499 	sblock.fs_fmod = 0;
    500 	sblock.fs_ronly = 0;
    501 	sblock.fs_state = 0;
    502 	sblock.fs_clean = FS_ISCLEAN;
    503 	sblock.fs_ronly = 0;
    504 	sblock.fs_id[0] = (long)tv.tv_sec;	/* XXXfvdl huh? */
    505 	sblock.fs_id[1] = arc4random() & INT32_MAX;
    506 	sblock.fs_fsmnt[0] = '\0';
    507 	csfrags = howmany(sblock.fs_cssize, sblock.fs_fsize);
    508 	sblock.fs_dsize = sblock.fs_size - sblock.fs_sblkno -
    509 	    sblock.fs_ncg * (sblock.fs_dblkno - sblock.fs_sblkno);
    510 	sblock.fs_cstotal.cs_nbfree =
    511 	    fragstoblks(&sblock, sblock.fs_dsize) -
    512 	    howmany(csfrags, sblock.fs_frag);
    513 	sblock.fs_cstotal.cs_nffree =
    514 	    fragnum(&sblock, sblock.fs_size) +
    515 	    (fragnum(&sblock, csfrags) > 0 ?
    516 	    sblock.fs_frag - fragnum(&sblock, csfrags) : 0);
    517 	sblock.fs_cstotal.cs_nifree = sblock.fs_ncg * sblock.fs_ipg - UFS_ROOTINO;
    518 	sblock.fs_cstotal.cs_ndir = 0;
    519 	sblock.fs_dsize -= csfrags;
    520 	sblock.fs_time = tv.tv_sec;
    521 	if (Oflag <= 1) {
    522 		sblock.fs_old_time = tv.tv_sec;
    523 		sblock.fs_old_dsize = sblock.fs_dsize;
    524 		sblock.fs_old_csaddr = sblock.fs_csaddr;
    525 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
    526 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
    527 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
    528 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
    529 	}
    530 	/* add quota data in superblock */
    531 	if (quotas) {
    532 		sblock.fs_flags |= FS_DOQUOTA2;
    533 		sblock.fs_quota_magic = Q2_HEAD_MAGIC;
    534 		sblock.fs_quota_flags = quotas;
    535 	}
    536 	/*
    537 	 * Dump out summary information about file system.
    538 	 */
    539 	if (verbosity > 0) {
    540 #define	B2MBFACTOR (1 / (1024.0 * 1024.0))
    541 		printf("%s: %.1fMB (%lld sectors) block size %d, "
    542 		       "fragment size %d\n",
    543 		    fsys, (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
    544 		    (long long)FFS_FSBTODB(&sblock, sblock.fs_size),
    545 		    sblock.fs_bsize, sblock.fs_fsize);
    546 		printf("\tusing %d cylinder groups of %.2fMB, %d blks, "
    547 		       "%d inodes.\n",
    548 		    sblock.fs_ncg,
    549 		    (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
    550 		    sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
    551 #undef B2MBFACTOR
    552 	}
    553 
    554 	/*
    555 	 * allocate space for superblock, cylinder group map, and
    556 	 * two sets of inode blocks.
    557 	 */
    558 	if (sblock.fs_bsize < SBLOCKSIZE)
    559 		iobufsize = SBLOCKSIZE + 3 * sblock.fs_bsize;
    560 	else
    561 		iobufsize = 4 * sblock.fs_bsize;
    562 	iobuf_memsize = iobufsize;
    563 	if (!mfs && sblock.fs_magic == FS_UFS1_MAGIC) {
    564 		/* A larger buffer so we can write multiple inode blks */
    565 		iobuf_memsize += 14 * sblock.fs_bsize;
    566 	}
    567 	for (;;) {
    568 		iobuf = mmap(0, iobuf_memsize, PROT_READ|PROT_WRITE,
    569 				MAP_ANON|MAP_PRIVATE, -1, 0);
    570 		if (iobuf != MAP_FAILED)
    571 			break;
    572 		if (iobuf_memsize != iobufsize) {
    573 			/* Try again with the smaller size */
    574 			iobuf_memsize = iobufsize;
    575 			continue;
    576 		}
    577 		printf("Cannot allocate I/O buffer\n");
    578 		exit(38);
    579 	}
    580 	memset(iobuf, 0, iobuf_memsize);
    581 
    582 	/*
    583 	 * We now start writing to the filesystem
    584 	 */
    585 
    586 	if (!Nflag) {
    587 		/*
    588 		 * Validate the given file system size.
    589 		 * Verify that its last block can actually be accessed.
    590 		 * Convert to file system fragment sized units.
    591 		 */
    592 		if (fssize <= 0) {
    593 			printf("preposterous size %lld\n", (long long)fssize);
    594 			fserr(13);
    595 		}
    596 		wtfs(fssize - 1, sectorsize, iobuf);
    597 
    598 		/*
    599 		 * Ensure there is nothing that looks like a filesystem
    600 		 * superbock anywhere other than where ours will be.
    601 		 * If fsck finds the wrong one all hell breaks loose!
    602 		 */
    603 		for (i = 0; ; i++) {
    604 			static const int sblocklist[] = SBLOCKSEARCH;
    605 			int sblkoff = sblocklist[i];
    606 			int sz;
    607 			if (sblkoff == -1)
    608 				break;
    609 			/* Remove main superblock */
    610 			zap_old_sblock(sblkoff);
    611 			/* and all possible locations for the first alternate */
    612 			sblkoff += SBLOCKSIZE;
    613 			for (sz = SBLOCKSIZE; sz <= 0x10000; sz <<= 1)
    614 				zap_old_sblock(roundup(sblkoff, sz));
    615 		}
    616 		/*
    617 		 * Also zap possible Ext2fs magic leftover to prevent
    618 		 * kernel vfs_mountroot() and bootloaders from mis-recognizing
    619 		 * this file system as Ext2fs.
    620 		 */
    621 		zap_old_sblock(EXT2FS_SBOFF);
    622 
    623 		if (isappleufs) {
    624 			struct appleufslabel appleufs;
    625 			ffs_appleufs_set(&appleufs, appleufs_volname,
    626 			    tv.tv_sec, 0);
    627 			wtfs(APPLEUFS_LABEL_OFFSET/sectorsize,
    628 			    APPLEUFS_LABEL_SIZE, &appleufs);
    629 		} else if (APPLEUFS_LABEL_SIZE % sectorsize == 0) {
    630 			struct appleufslabel appleufs;
    631 			/* Look for & zap any existing valid apple ufs labels */
    632 			rdfs(APPLEUFS_LABEL_OFFSET/sectorsize,
    633 			    APPLEUFS_LABEL_SIZE, &appleufs);
    634 			if (ffs_appleufs_validate(fsys, &appleufs, NULL) == 0) {
    635 				memset(&appleufs, 0, sizeof(appleufs));
    636 				wtfs(APPLEUFS_LABEL_OFFSET/sectorsize,
    637 				    APPLEUFS_LABEL_SIZE, &appleufs);
    638 			}
    639 		}
    640 	}
    641 
    642 	/*
    643 	 * Make a copy of the superblock into the buffer that we will be
    644 	 * writing out in each cylinder group.
    645 	 */
    646 	memcpy(iobuf, &sblock, sizeof sblock);
    647 	if (needswap)
    648 		ffs_sb_swap(&sblock, (struct fs *)iobuf);
    649 	if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0)
    650 		memset(iobuf + offsetof(struct fs, fs_old_postbl_start),
    651 		    0xff, 256);
    652 
    653 	if (verbosity >= 3)
    654 		printf("super-block backups (for fsck_ffs -b #) at:\n");
    655 	/* If we are printing more than one line of numbers, line up columns */
    656 	fld_width = verbosity < 4 ? 1 : snprintf(NULL, 0, "%" PRIu64,
    657 		(uint64_t)FFS_FSBTODB(&sblock, cgsblock(&sblock, sblock.fs_ncg-1)));
    658 	/* Get terminal width */
    659 	if (ioctl(fileno(stdout), TIOCGWINSZ, &winsize) == 0)
    660 		max_cols = winsize.ws_col;
    661 	else
    662 		max_cols = 80;
    663 	if (Nflag && verbosity == 3)
    664 		/* Leave space to add " ..." after one row of numbers */
    665 		max_cols -= 4;
    666 #define BASE 0x10000	/* For some fixed-point maths */
    667 	col = 0;
    668 	delta = verbosity > 2 ? 0 : max_cols * BASE / sblock.fs_ncg;
    669 	for (cylno = 0; cylno < sblock.fs_ncg; cylno++) {
    670 		fflush(stdout);
    671 		initcg(cylno, &tv);
    672 		if (verbosity < 2)
    673 			continue;
    674 		if (delta > 0) {
    675 			if (Nflag)
    676 				/* No point doing dots for -N */
    677 				break;
    678 			/* Print dots scaled to end near RH margin */
    679 			for (col += delta; col > BASE; col -= BASE)
    680 				printf(".");
    681 			continue;
    682 		}
    683 		/* Print superblock numbers */
    684 		len = printf("%s%*" PRIu64 ",", col ? " " : "", fld_width,
    685 		    (uint64_t)FFS_FSBTODB(&sblock, cgsblock(&sblock, cylno)));
    686 		col += len;
    687 		if (col + len < max_cols)
    688 			/* Next number fits */
    689 			continue;
    690 		/* Next number won't fit, need a newline */
    691 		if (verbosity <= 3) {
    692 			/* Print dots for subsequent cylinder groups */
    693 			delta = sblock.fs_ncg - cylno - 1;
    694 			if (delta != 0) {
    695 				if (Nflag) {
    696 					printf(" ...");
    697 					break;
    698 				}
    699 				delta = max_cols * BASE / delta;
    700 			}
    701 		}
    702 		col = 0;
    703 		printf("\n");
    704 	}
    705 #undef BASE
    706 	if (col > 0)
    707 		printf("\n");
    708 	if (Nflag)
    709 		exit(0);
    710 
    711 	/*
    712 	 * Now construct the initial file system,
    713 	 */
    714 	if (fsinit(&tv, mfsmode, mfsuid, mfsgid) == 0 && mfs)
    715 		errx(1, "Error making filesystem");
    716 	sblock.fs_time = tv.tv_sec;
    717 	if (Oflag <= 1) {
    718 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
    719 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
    720 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
    721 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
    722 	}
    723 	/*
    724 	 * Write out the super-block and zeros until the first cg info
    725 	 */
    726 	i = cgsblock(&sblock, 0) * sblock.fs_fsize - sblock.fs_sblockloc,
    727 	memset(iobuf, 0, i);
    728 	memcpy(iobuf, &sblock, sizeof sblock);
    729 	if (needswap)
    730 		ffs_sb_swap(&sblock, (struct fs *)iobuf);
    731 	if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0)
    732 		memset(iobuf + offsetof(struct fs, fs_old_postbl_start),
    733 		    0xff, 256);
    734 	wtfs(sblock.fs_sblockloc / sectorsize, i, iobuf);
    735 
    736 	/* Write out first and last cylinder summary sectors */
    737 	if (needswap)
    738 		ffs_csum_swap(fscs_0, fscs_0, sblock.fs_fsize);
    739 	wtfs(FFS_FSBTODB(&sblock, sblock.fs_csaddr), sblock.fs_fsize, fscs_0);
    740 
    741 	if (fscs_next > fscs_reset) {
    742 		if (needswap)
    743 			ffs_csum_swap(fscs_reset, fscs_reset, sblock.fs_fsize);
    744 		fs_csaddr++;
    745 		wtfs(FFS_FSBTODB(&sblock, fs_csaddr), sblock.fs_fsize, fscs_reset);
    746 	}
    747 
    748 	/* mfs doesn't need these permanently allocated */
    749 	munmap(iobuf, iobuf_memsize);
    750 	munmap(fscs_0, 2 * sblock.fs_fsize);
    751 }
    752 
    753 /*
    754  * Initialize a cylinder group.
    755  */
    756 void
    757 initcg(int cylno, const struct timeval *tv)
    758 {
    759 	daddr_t cbase, dmax;
    760 	int32_t i, d, dlower, dupper, blkno;
    761 	uint32_t u;
    762 	struct ufs1_dinode *dp1;
    763 	struct ufs2_dinode *dp2;
    764 	int start;
    765 
    766 	/*
    767 	 * Determine block bounds for cylinder group.
    768 	 * Allow space for super block summary information in first
    769 	 * cylinder group.
    770 	 */
    771 	cbase = cgbase(&sblock, cylno);
    772 	dmax = cbase + sblock.fs_fpg;
    773 	if (dmax > sblock.fs_size)
    774 		dmax = sblock.fs_size;
    775 	dlower = cgsblock(&sblock, cylno) - cbase;
    776 	dupper = cgdmin(&sblock, cylno) - cbase;
    777 	if (cylno == 0) {
    778 		dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
    779 		if (dupper >= cgstart(&sblock, cylno + 1)) {
    780 			printf("\rToo many cylinder groups to fit summary "
    781 				"information into first cylinder group\n");
    782 			fserr(40);
    783 		}
    784 	}
    785 	memset(&acg, 0, sblock.fs_cgsize);
    786 	acg.cg_magic = CG_MAGIC;
    787 	acg.cg_cgx = cylno;
    788 	acg.cg_ndblk = dmax - cbase;
    789 	if (sblock.fs_contigsumsize > 0)
    790 		acg.cg_nclusterblks = acg.cg_ndblk >> sblock.fs_fragshift;
    791 	start = &acg.cg_space[0] - (u_char *)(&acg.cg_firstfield);
    792 	if (Oflag == 2) {
    793 		acg.cg_time = tv->tv_sec;
    794 		acg.cg_niblk = sblock.fs_ipg;
    795 		acg.cg_initediblk = sblock.fs_ipg < 2 * FFS_INOPB(&sblock) ?
    796 		    sblock.fs_ipg : 2 * FFS_INOPB(&sblock);
    797 		acg.cg_iusedoff = start;
    798 	} else {
    799 		acg.cg_old_ncyl = sblock.fs_old_cpg;
    800 		if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0 &&
    801 		    (cylno == sblock.fs_ncg - 1))
    802 			acg.cg_old_ncyl =
    803 			    sblock.fs_old_ncyl % sblock.fs_old_cpg;
    804 		acg.cg_old_time = tv->tv_sec;
    805 		acg.cg_old_niblk = sblock.fs_ipg;
    806 		acg.cg_old_btotoff = start;
    807 		acg.cg_old_boff = acg.cg_old_btotoff +
    808 		    sblock.fs_old_cpg * sizeof(int32_t);
    809 		acg.cg_iusedoff = acg.cg_old_boff +
    810 		    sblock.fs_old_cpg * sizeof(u_int16_t);
    811 	}
    812 	acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
    813 	if (sblock.fs_contigsumsize <= 0) {
    814 		acg.cg_nextfreeoff = acg.cg_freeoff +
    815 		   howmany(sblock.fs_fpg, CHAR_BIT);
    816 	} else {
    817 		acg.cg_clustersumoff = acg.cg_freeoff +
    818 		    howmany(sblock.fs_fpg, CHAR_BIT) - sizeof(int32_t);
    819 		if (isappleufs) {
    820 			/* Apple PR2216969 gives rationale for this change.
    821 			 * I believe they were mistaken, but we need to
    822 			 * duplicate it for compatibility.  -- dbj (at) NetBSD.org
    823 			 */
    824 			acg.cg_clustersumoff += sizeof(int32_t);
    825 		}
    826 		acg.cg_clustersumoff =
    827 		    roundup(acg.cg_clustersumoff, sizeof(int32_t));
    828 		acg.cg_clusteroff = acg.cg_clustersumoff +
    829 		    (sblock.fs_contigsumsize + 1) * sizeof(int32_t);
    830 		acg.cg_nextfreeoff = acg.cg_clusteroff +
    831 		    howmany(fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
    832 	}
    833 	if (acg.cg_nextfreeoff > sblock.fs_cgsize) {
    834 		printf("Panic: cylinder group too big\n");
    835 		fserr(37);
    836 	}
    837 	acg.cg_cs.cs_nifree += sblock.fs_ipg;
    838 	if (cylno == 0)
    839 		for (u = 0; u < UFS_ROOTINO; u++) {
    840 			setbit(cg_inosused(&acg, 0), u);
    841 			acg.cg_cs.cs_nifree--;
    842 		}
    843 	if (cylno > 0) {
    844 		/*
    845 		 * In cylno 0, beginning space is reserved
    846 		 * for boot and super blocks.
    847 		 */
    848 		for (d = 0, blkno = 0; d < dlower;) {
    849 			setblock(&sblock, cg_blksfree(&acg, 0), blkno);
    850 			if (sblock.fs_contigsumsize > 0)
    851 				setbit(cg_clustersfree(&acg, 0), blkno);
    852 			acg.cg_cs.cs_nbfree++;
    853 			if (Oflag <= 1) {
    854 				int cn = old_cbtocylno(&sblock, d);
    855 				old_cg_blktot(&acg, 0)[cn]++;
    856 				old_cg_blks(&sblock, &acg,
    857 				    cn, 0)[old_cbtorpos(&sblock, d)]++;
    858 			}
    859 			d += sblock.fs_frag;
    860 			blkno++;
    861 		}
    862 	}
    863 	if ((i = (dupper & (sblock.fs_frag - 1))) != 0) {
    864 		acg.cg_frsum[sblock.fs_frag - i]++;
    865 		for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
    866 			setbit(cg_blksfree(&acg, 0), dupper);
    867 			acg.cg_cs.cs_nffree++;
    868 		}
    869 	}
    870 	for (d = dupper, blkno = dupper >> sblock.fs_fragshift;
    871 	     d + sblock.fs_frag <= acg.cg_ndblk; ) {
    872 		setblock(&sblock, cg_blksfree(&acg, 0), blkno);
    873 		if (sblock.fs_contigsumsize > 0)
    874 			setbit(cg_clustersfree(&acg, 0), blkno);
    875 		acg.cg_cs.cs_nbfree++;
    876 		if (Oflag <= 1) {
    877 			int cn = old_cbtocylno(&sblock, d);
    878 			old_cg_blktot(&acg, 0)[cn]++;
    879 			old_cg_blks(&sblock, &acg,
    880 			    cn, 0)[old_cbtorpos(&sblock, d)]++;
    881 		}
    882 		d += sblock.fs_frag;
    883 		blkno++;
    884 	}
    885 	if (d < acg.cg_ndblk) {
    886 		acg.cg_frsum[acg.cg_ndblk - d]++;
    887 		for (; d < acg.cg_ndblk; d++) {
    888 			setbit(cg_blksfree(&acg, 0), d);
    889 			acg.cg_cs.cs_nffree++;
    890 		}
    891 	}
    892 	if (sblock.fs_contigsumsize > 0) {
    893 		int32_t *sump = cg_clustersum(&acg, 0);
    894 		u_char *mapp = cg_clustersfree(&acg, 0);
    895 		int map = *mapp++;
    896 		int bit = 1;
    897 		int run = 0;
    898 
    899 		for (i = 0; i < acg.cg_nclusterblks; i++) {
    900 			if ((map & bit) != 0) {
    901 				run++;
    902 			} else if (run != 0) {
    903 				if (run > sblock.fs_contigsumsize)
    904 					run = sblock.fs_contigsumsize;
    905 				sump[run]++;
    906 				run = 0;
    907 			}
    908 			if ((i & (CHAR_BIT - 1)) != (CHAR_BIT - 1)) {
    909 				bit <<= 1;
    910 			} else {
    911 				map = *mapp++;
    912 				bit = 1;
    913 			}
    914 		}
    915 		if (run != 0) {
    916 			if (run > sblock.fs_contigsumsize)
    917 				run = sblock.fs_contigsumsize;
    918 			sump[run]++;
    919 		}
    920 	}
    921 	*fscs_next++ = acg.cg_cs;
    922 	if (fscs_next == fscs_end) {
    923 		/* write block of cylinder group summary info into cyl 0 */
    924 		if (needswap)
    925 			ffs_csum_swap(fscs_reset, fscs_reset, sblock.fs_fsize);
    926 		fs_csaddr++;
    927 		wtfs(FFS_FSBTODB(&sblock, fs_csaddr), sblock.fs_fsize, fscs_reset);
    928 		fscs_next = fscs_reset;
    929 		memset(fscs_next, 0, sblock.fs_fsize);
    930 	}
    931 	/*
    932 	 * Write out the duplicate super block, the cylinder group map
    933 	 * and two blocks worth of inodes in a single write.
    934 	 */
    935 	start = sblock.fs_bsize > SBLOCKSIZE ? sblock.fs_bsize : SBLOCKSIZE;
    936 	memcpy(&iobuf[start], &acg, sblock.fs_cgsize);
    937 	if (needswap)
    938 		ffs_cg_swap(&acg, (struct cg*)&iobuf[start], &sblock);
    939 	start += sblock.fs_bsize;
    940 	dp1 = (struct ufs1_dinode *)(&iobuf[start]);
    941 	dp2 = (struct ufs2_dinode *)(&iobuf[start]);
    942 	for (i = MIN(sblock.fs_ipg, 2) * FFS_INOPB(&sblock); i != 0; i--) {
    943 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
    944 			/* No need to swap, it'll stay random */
    945 			dp1->di_gen = arc4random() & INT32_MAX;
    946 			dp1++;
    947 		} else {
    948 			dp2->di_gen = arc4random() & INT32_MAX;
    949 			dp2++;
    950 		}
    951 	}
    952 	wtfs(FFS_FSBTODB(&sblock, cgsblock(&sblock, cylno)), iobufsize, iobuf);
    953 	/*
    954 	 * For the old file system, we have to initialize all the inodes.
    955 	 */
    956 	if (sblock.fs_magic != FS_UFS1_MAGIC)
    957 		return;
    958 
    959 	/* Write 'd' (usually 16 * fs_frag) file-system fragments at once */
    960 	d = (iobuf_memsize - start) / sblock.fs_bsize * sblock.fs_frag;
    961 	dupper = sblock.fs_ipg / FFS_INOPF(&sblock);
    962 	for (i = 2 * sblock.fs_frag; i < dupper; i += d) {
    963 		if (d > dupper - i)
    964 			d = dupper - i;
    965 		dp1 = (struct ufs1_dinode *)(&iobuf[start]);
    966 		do
    967 			dp1->di_gen = arc4random() & INT32_MAX;
    968 		while ((char *)++dp1 < &iobuf[iobuf_memsize]);
    969 		wtfs(FFS_FSBTODB(&sblock, cgimin(&sblock, cylno) + i),
    970 		    d * sblock.fs_bsize / sblock.fs_frag, &iobuf[start]);
    971 	}
    972 }
    973 
    974 /*
    975  * initialize the file system
    976  */
    977 
    978 #ifdef LOSTDIR
    979 #define	PREDEFDIR 3
    980 #else
    981 #define	PREDEFDIR 2
    982 #endif
    983 
    984 struct direct root_dir[] = {
    985 	{ UFS_ROOTINO, sizeof(struct direct), DT_DIR, 1, "." },
    986 	{ UFS_ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
    987 #ifdef LOSTDIR
    988 	{ LOSTFOUNDINO, sizeof(struct direct), DT_DIR, 10, "lost+found" },
    989 #endif
    990 };
    991 struct odirect {
    992 	u_int32_t d_ino;
    993 	u_int16_t d_reclen;
    994 	u_int16_t d_namlen;
    995 	u_char	d_name[FFS_MAXNAMLEN + 1];
    996 } oroot_dir[] = {
    997 	{ UFS_ROOTINO, sizeof(struct direct), 1, "." },
    998 	{ UFS_ROOTINO, sizeof(struct direct), 2, ".." },
    999 #ifdef LOSTDIR
   1000 	{ LOSTFOUNDINO, sizeof(struct direct), 10, "lost+found" },
   1001 #endif
   1002 };
   1003 #ifdef LOSTDIR
   1004 struct direct lost_found_dir[] = {
   1005 	{ LOSTFOUNDINO, sizeof(struct direct), DT_DIR, 1, "." },
   1006 	{ UFS_ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
   1007 	{ 0, DIRBLKSIZ, 0, 0, 0 },
   1008 };
   1009 struct odirect olost_found_dir[] = {
   1010 	{ LOSTFOUNDINO, sizeof(struct direct), 1, "." },
   1011 	{ UFS_ROOTINO, sizeof(struct direct), 2, ".." },
   1012 	{ 0, DIRBLKSIZ, 0, 0 },
   1013 };
   1014 #endif
   1015 char buf[MAXBSIZE];
   1016 static void copy_dir(struct direct *, struct direct *);
   1017 
   1018 int
   1019 fsinit(const struct timeval *tv, mode_t mfsmode, uid_t mfsuid, gid_t mfsgid)
   1020 {
   1021 	union dinode node;
   1022 	int i;
   1023 	int qblocks = 0;
   1024 	int qinos = 0;
   1025 	uint8_t q2h_hash_shift;
   1026 	uint16_t q2h_hash_mask;
   1027 #ifdef LOSTDIR
   1028 	int dirblksiz = DIRBLKSIZ;
   1029 	if (isappleufs)
   1030 		dirblksiz = APPLEUFS_DIRBLKSIZ;
   1031 	int nextino = LOSTFOUNDINO+1;
   1032 #else
   1033 	int nextino = UFS_ROOTINO+1;
   1034 #endif
   1035 
   1036 	/*
   1037 	 * initialize the node
   1038 	 */
   1039 
   1040 #ifdef LOSTDIR
   1041 	/*
   1042 	 * create the lost+found directory
   1043 	 */
   1044 	memset(&node, 0, sizeof(node));
   1045 	if (Oflag == 0) {
   1046 		(void)makedir((struct direct *)olost_found_dir, 2);
   1047 		for (i = dirblksiz; i < sblock.fs_bsize; i += dirblksiz)
   1048 			copy_dir((struct direct*)&olost_found_dir[2],
   1049 				(struct direct*)&buf[i]);
   1050 	} else {
   1051 		(void)makedir(lost_found_dir, 2);
   1052 		for (i = dirblksiz; i < sblock.fs_bsize; i += dirblksiz)
   1053 			copy_dir(&lost_found_dir[2], (struct direct*)&buf[i]);
   1054 	}
   1055 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
   1056 		node.dp1.di_atime = tv->tv_sec;
   1057 		node.dp1.di_atimensec = tv->tv_usec * 1000;
   1058 		node.dp1.di_mtime = tv->tv_sec;
   1059 		node.dp1.di_mtimensec = tv->tv_usec * 1000;
   1060 		node.dp1.di_ctime = tv->tv_sec;
   1061 		node.dp1.di_ctimensec = tv->tv_usec * 1000;
   1062 		node.dp1.di_mode = IFDIR | UMASK;
   1063 		node.dp1.di_nlink = 2;
   1064 		node.dp1.di_size = sblock.fs_bsize;
   1065 		node.dp1.di_db[0] = alloc(node.dp1.di_size, node.dp1.di_mode);
   1066 		if (node.dp1.di_db[0] == 0)
   1067 			return (0);
   1068 		node.dp1.di_blocks = btodb(ffs_fragroundup(&sblock,
   1069 		    node.dp1.di_size));
   1070 		qblocks += node.dp1.di_blocks;
   1071 		node.dp1.di_uid = geteuid();
   1072 		node.dp1.di_gid = getegid();
   1073 		wtfs(FFS_FSBTODB(&sblock, node.dp1.di_db[0]), node.dp1.di_size,
   1074 		    buf);
   1075 	} else {
   1076 		node.dp2.di_atime = tv->tv_sec;
   1077 		node.dp2.di_atimensec = tv->tv_usec * 1000;
   1078 		node.dp2.di_mtime = tv->tv_sec;
   1079 		node.dp2.di_mtimensec = tv->tv_usec * 1000;
   1080 		node.dp2.di_ctime = tv->tv_sec;
   1081 		node.dp2.di_ctimensec = tv->tv_usec * 1000;
   1082 		node.dp2.di_birthtime = tv->tv_sec;
   1083 		node.dp2.di_birthnsec = tv->tv_usec * 1000;
   1084 		node.dp2.di_mode = IFDIR | UMASK;
   1085 		node.dp2.di_nlink = 2;
   1086 		node.dp2.di_size = sblock.fs_bsize;
   1087 		node.dp2.di_db[0] = alloc(node.dp2.di_size, node.dp2.di_mode);
   1088 		if (node.dp2.di_db[0] == 0)
   1089 			return (0);
   1090 		node.dp2.di_blocks = btodb(ffs_fragroundup(&sblock,
   1091 		    node.dp2.di_size));
   1092 		qblocks += node.dp2.di_blocks;
   1093 		node.dp2.di_uid = geteuid();
   1094 		node.dp2.di_gid = getegid();
   1095 		wtfs(FFS_FSBTODB(&sblock, node.dp2.di_db[0]), node.dp2.di_size,
   1096 		    buf);
   1097 	}
   1098 	qinos++;
   1099 	iput(&node, LOSTFOUNDINO);
   1100 #endif
   1101 	/*
   1102 	 * create the root directory
   1103 	 */
   1104 	memset(&node, 0, sizeof(node));
   1105 	if (Oflag <= 1) {
   1106 		if (mfs) {
   1107 			node.dp1.di_mode = IFDIR | mfsmode;
   1108 			node.dp1.di_uid = mfsuid;
   1109 			node.dp1.di_gid = mfsgid;
   1110 		} else {
   1111 			node.dp1.di_mode = IFDIR | UMASK;
   1112 			node.dp1.di_uid = geteuid();
   1113 			node.dp1.di_gid = getegid();
   1114 		}
   1115 		node.dp1.di_nlink = PREDEFDIR;
   1116 		if (Oflag == 0)
   1117 			node.dp1.di_size = makedir((struct direct *)oroot_dir,
   1118 			    PREDEFDIR);
   1119 		else
   1120 			node.dp1.di_size = makedir(root_dir, PREDEFDIR);
   1121 		node.dp1.di_db[0] = alloc(sblock.fs_fsize, node.dp1.di_mode);
   1122 		if (node.dp1.di_db[0] == 0)
   1123 			return (0);
   1124 		node.dp1.di_blocks = btodb(ffs_fragroundup(&sblock,
   1125 		    node.dp1.di_size));
   1126 		qblocks += node.dp1.di_blocks;
   1127 		wtfs(FFS_FSBTODB(&sblock, node.dp1.di_db[0]), sblock.fs_fsize, buf);
   1128 	} else {
   1129 		if (mfs) {
   1130 			node.dp2.di_mode = IFDIR | mfsmode;
   1131 			node.dp2.di_uid = mfsuid;
   1132 			node.dp2.di_gid = mfsgid;
   1133 		} else {
   1134 			node.dp2.di_mode = IFDIR | UMASK;
   1135 			node.dp2.di_uid = geteuid();
   1136 			node.dp2.di_gid = getegid();
   1137 		}
   1138 		node.dp2.di_atime = tv->tv_sec;
   1139 		node.dp2.di_atimensec = tv->tv_usec * 1000;
   1140 		node.dp2.di_mtime = tv->tv_sec;
   1141 		node.dp2.di_mtimensec = tv->tv_usec * 1000;
   1142 		node.dp2.di_ctime = tv->tv_sec;
   1143 		node.dp2.di_ctimensec = tv->tv_usec * 1000;
   1144 		node.dp2.di_birthtime = tv->tv_sec;
   1145 		node.dp2.di_birthnsec = tv->tv_usec * 1000;
   1146 		node.dp2.di_nlink = PREDEFDIR;
   1147 		node.dp2.di_size = makedir(root_dir, PREDEFDIR);
   1148 		node.dp2.di_db[0] = alloc(sblock.fs_fsize, node.dp2.di_mode);
   1149 		if (node.dp2.di_db[0] == 0)
   1150 			return (0);
   1151 		node.dp2.di_blocks = btodb(ffs_fragroundup(&sblock,
   1152 		    node.dp2.di_size));
   1153 		qblocks += node.dp2.di_blocks;
   1154 		wtfs(FFS_FSBTODB(&sblock, node.dp2.di_db[0]), sblock.fs_fsize, buf);
   1155 	}
   1156 	qinos++;
   1157 	iput(&node, UFS_ROOTINO);
   1158 	/*
   1159 	 * compute the size of the hash table
   1160 	 * We know the smallest block size is 4k, so we can use 2k
   1161 	 * for the hash table; as an entry is 8 bytes we can store
   1162 	 * 256 entries. So let start q2h_hash_shift at 8
   1163 	 */
   1164 	for (q2h_hash_shift = 8;
   1165 	    q2h_hash_shift < 15;
   1166 	    q2h_hash_shift++) {
   1167 		if ((sizeof(uint64_t) << (q2h_hash_shift + 1)) +
   1168 		    sizeof(struct quota2_header) > (u_int)sblock.fs_bsize)
   1169 			break;
   1170 	}
   1171 	q2h_hash_mask = (1 << q2h_hash_shift) - 1;
   1172 	for (i = 0; i < MAXQUOTAS; i++) {
   1173 		struct quota2_header *q2h;
   1174 		struct quota2_entry *q2e;
   1175 		uint64_t offset;
   1176 		uid_t uid = (i == USRQUOTA ? geteuid() : getegid());
   1177 
   1178 		if ((quotas & FS_Q2_DO_TYPE(i)) == 0)
   1179 			continue;
   1180 		quota2_create_blk0(sblock.fs_bsize, buf, q2h_hash_shift,
   1181 		    i, needswap);
   1182 		/* grab an entry from header for root dir */
   1183 		q2h = (void *)buf;
   1184 		offset = ufs_rw64(q2h->q2h_free, needswap);
   1185 		q2e = (void *)((char *)buf + offset);
   1186 		q2h->q2h_free = q2e->q2e_next;
   1187 		memcpy(q2e, &q2h->q2h_defentry, sizeof(*q2e));
   1188 		q2e->q2e_uid = ufs_rw32(uid, needswap);
   1189 		q2e->q2e_val[QL_BLOCK].q2v_cur = ufs_rw64(qblocks, needswap);
   1190 		q2e->q2e_val[QL_FILE].q2v_cur = ufs_rw64(qinos, needswap);
   1191 		/* add to the hash entry */
   1192 		q2e->q2e_next = q2h->q2h_entries[uid & q2h_hash_mask];
   1193 		q2h->q2h_entries[uid & q2h_hash_mask] =
   1194 		    ufs_rw64(offset, needswap);
   1195 
   1196 		memset(&node, 0, sizeof(node));
   1197 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
   1198 			node.dp1.di_atime = tv->tv_sec;
   1199 			node.dp1.di_atimensec = tv->tv_usec * 1000;
   1200 			node.dp1.di_mtime = tv->tv_sec;
   1201 			node.dp1.di_mtimensec = tv->tv_usec * 1000;
   1202 			node.dp1.di_ctime = tv->tv_sec;
   1203 			node.dp1.di_ctimensec = tv->tv_usec * 1000;
   1204 			node.dp1.di_mode = IFREG;
   1205 			node.dp1.di_nlink = 1;
   1206 			node.dp1.di_size = sblock.fs_bsize;
   1207 			node.dp1.di_db[0] =
   1208 			    alloc(node.dp1.di_size, node.dp1.di_mode);
   1209 			if (node.dp1.di_db[0] == 0)
   1210 				return (0);
   1211 			node.dp1.di_blocks = btodb(ffs_fragroundup(&sblock,
   1212 			    node.dp1.di_size));
   1213 			node.dp1.di_uid = geteuid();
   1214 			node.dp1.di_gid = getegid();
   1215 			wtfs(FFS_FSBTODB(&sblock, node.dp1.di_db[0]),
   1216 			     node.dp1.di_size, buf);
   1217 		} else {
   1218 			node.dp2.di_atime = tv->tv_sec;
   1219 			node.dp2.di_atimensec = tv->tv_usec * 1000;
   1220 			node.dp2.di_mtime = tv->tv_sec;
   1221 			node.dp2.di_mtimensec = tv->tv_usec * 1000;
   1222 			node.dp2.di_ctime = tv->tv_sec;
   1223 			node.dp2.di_ctimensec = tv->tv_usec * 1000;
   1224 			node.dp2.di_birthtime = tv->tv_sec;
   1225 			node.dp2.di_birthnsec = tv->tv_usec * 1000;
   1226 			node.dp2.di_mode = IFREG;
   1227 			node.dp2.di_nlink = 1;
   1228 			node.dp2.di_size = sblock.fs_bsize;
   1229 			node.dp2.di_db[0] =
   1230 			    alloc(node.dp2.di_size, node.dp2.di_mode);
   1231 			if (node.dp2.di_db[0] == 0)
   1232 				return (0);
   1233 			node.dp2.di_blocks = btodb(ffs_fragroundup(&sblock,
   1234 			    node.dp2.di_size));
   1235 			node.dp2.di_uid = geteuid();
   1236 			node.dp2.di_gid = getegid();
   1237 			wtfs(FFS_FSBTODB(&sblock, node.dp2.di_db[0]),
   1238 			    node.dp2.di_size, buf);
   1239 		}
   1240 		iput(&node, nextino);
   1241 		sblock.fs_quotafile[i] = nextino;
   1242 		nextino++;
   1243 	}
   1244 	return (1);
   1245 }
   1246 
   1247 /*
   1248  * construct a set of directory entries in "buf".
   1249  * return size of directory.
   1250  */
   1251 int
   1252 makedir(struct direct *protodir, int entries)
   1253 {
   1254 	char *cp;
   1255 	int i, spcleft;
   1256 	int dirblksiz = UFS_DIRBLKSIZ;
   1257 	if (isappleufs)
   1258 		dirblksiz = APPLEUFS_DIRBLKSIZ;
   1259 
   1260 	memset(buf, 0, UFS_DIRBLKSIZ);
   1261 	spcleft = dirblksiz;
   1262 	for (cp = buf, i = 0; i < entries - 1; i++) {
   1263 		protodir[i].d_reclen = UFS_DIRSIZ(Oflag == 0, &protodir[i], 0);
   1264 		copy_dir(&protodir[i], (struct direct*)cp);
   1265 		cp += protodir[i].d_reclen;
   1266 		spcleft -= protodir[i].d_reclen;
   1267 	}
   1268 	protodir[i].d_reclen = spcleft;
   1269 	copy_dir(&protodir[i], (struct direct*)cp);
   1270 	return (dirblksiz);
   1271 }
   1272 
   1273 /*
   1274  * allocate a block or frag
   1275  */
   1276 daddr_t
   1277 alloc(int size, int mode)
   1278 {
   1279 	int i, frag;
   1280 	daddr_t d, blkno;
   1281 
   1282 	rdfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
   1283 	/* fs -> host byte order */
   1284 	if (needswap)
   1285 		ffs_cg_swap(&acg, &acg, &sblock);
   1286 	if (acg.cg_magic != CG_MAGIC) {
   1287 		printf("cg 0: bad magic number\n");
   1288 		return (0);
   1289 	}
   1290 	if (acg.cg_cs.cs_nbfree == 0) {
   1291 		printf("first cylinder group ran out of space\n");
   1292 		return (0);
   1293 	}
   1294 	for (d = 0; d < acg.cg_ndblk; d += sblock.fs_frag)
   1295 		if (isblock(&sblock, cg_blksfree(&acg, 0),
   1296 		    d >> sblock.fs_fragshift))
   1297 			goto goth;
   1298 	printf("internal error: can't find block in cyl 0\n");
   1299 	return (0);
   1300 goth:
   1301 	blkno = fragstoblks(&sblock, d);
   1302 	clrblock(&sblock, cg_blksfree(&acg, 0), blkno);
   1303 	if (sblock.fs_contigsumsize > 0)
   1304 		clrbit(cg_clustersfree(&acg, 0), blkno);
   1305 	acg.cg_cs.cs_nbfree--;
   1306 	sblock.fs_cstotal.cs_nbfree--;
   1307 	fscs_0->cs_nbfree--;
   1308 	if (mode & IFDIR) {
   1309 		acg.cg_cs.cs_ndir++;
   1310 		sblock.fs_cstotal.cs_ndir++;
   1311 		fscs_0->cs_ndir++;
   1312 	}
   1313 	if (Oflag <= 1) {
   1314 		int cn = old_cbtocylno(&sblock, d);
   1315 		old_cg_blktot(&acg, 0)[cn]--;
   1316 		old_cg_blks(&sblock, &acg,
   1317 		    cn, 0)[old_cbtorpos(&sblock, d)]--;
   1318 	}
   1319 	if (size != sblock.fs_bsize) {
   1320 		frag = howmany(size, sblock.fs_fsize);
   1321 		fscs_0->cs_nffree += sblock.fs_frag - frag;
   1322 		sblock.fs_cstotal.cs_nffree += sblock.fs_frag - frag;
   1323 		acg.cg_cs.cs_nffree += sblock.fs_frag - frag;
   1324 		acg.cg_frsum[sblock.fs_frag - frag]++;
   1325 		for (i = frag; i < sblock.fs_frag; i++)
   1326 			setbit(cg_blksfree(&acg, 0), d + i);
   1327 	}
   1328 	/* host -> fs byte order */
   1329 	if (needswap)
   1330 		ffs_cg_swap(&acg, &acg, &sblock);
   1331 	wtfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
   1332 	return (d);
   1333 }
   1334 
   1335 /*
   1336  * Allocate an inode on the disk
   1337  */
   1338 static void
   1339 iput(union dinode *ip, ino_t ino)
   1340 {
   1341 	daddr_t d;
   1342 	int i;
   1343 	struct ufs1_dinode *dp1;
   1344 	struct ufs2_dinode *dp2;
   1345 
   1346 	rdfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
   1347 	/* fs -> host byte order */
   1348 	if (needswap)
   1349 		ffs_cg_swap(&acg, &acg, &sblock);
   1350 	if (acg.cg_magic != CG_MAGIC) {
   1351 		printf("cg 0: bad magic number\n");
   1352 		fserr(31);
   1353 	}
   1354 	acg.cg_cs.cs_nifree--;
   1355 	setbit(cg_inosused(&acg, 0), ino);
   1356 	/* host -> fs byte order */
   1357 	if (needswap)
   1358 		ffs_cg_swap(&acg, &acg, &sblock);
   1359 	wtfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
   1360 	sblock.fs_cstotal.cs_nifree--;
   1361 	fscs_0->cs_nifree--;
   1362 	if (ino >= (ino_t)(sblock.fs_ipg * sblock.fs_ncg)) {
   1363 		printf("fsinit: inode value out of range (%llu).\n",
   1364 		    (unsigned long long)ino);
   1365 		fserr(32);
   1366 	}
   1367 	d = FFS_FSBTODB(&sblock, ino_to_fsba(&sblock, ino));
   1368 	rdfs(d, sblock.fs_bsize, (char *)iobuf);
   1369 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
   1370 		dp1 = (struct ufs1_dinode *)iobuf;
   1371 		dp1 += ino_to_fsbo(&sblock, ino);
   1372 		if (needswap) {
   1373 			ffs_dinode1_swap(&ip->dp1, dp1);
   1374 			/* ffs_dinode1_swap() doesn't swap blocks addrs */
   1375 			for (i=0; i<UFS_NDADDR + UFS_NIADDR; i++)
   1376 			    dp1->di_db[i] = bswap32(ip->dp1.di_db[i]);
   1377 		} else
   1378 			*dp1 = ip->dp1;
   1379 		dp1->di_gen = arc4random() & INT32_MAX;
   1380 	} else {
   1381 		dp2 = (struct ufs2_dinode *)iobuf;
   1382 		dp2 += ino_to_fsbo(&sblock, ino);
   1383 		if (needswap) {
   1384 			ffs_dinode2_swap(&ip->dp2, dp2);
   1385 			for (i=0; i<UFS_NDADDR + UFS_NIADDR; i++)
   1386 			    dp2->di_db[i] = bswap64(ip->dp2.di_db[i]);
   1387 		} else
   1388 			*dp2 = ip->dp2;
   1389 		dp2->di_gen = arc4random() & INT32_MAX;
   1390 	}
   1391 	wtfs(d, sblock.fs_bsize, iobuf);
   1392 }
   1393 
   1394 /*
   1395  * read a block from the file system
   1396  */
   1397 void
   1398 rdfs(daddr_t bno, int size, void *bf)
   1399 {
   1400 	int n;
   1401 	off_t offset;
   1402 
   1403 #ifdef MFS
   1404 	if (mfs) {
   1405 		if (Nflag)
   1406 			memset(bf, 0, size);
   1407 		else
   1408 			memmove(bf, membase + bno * sectorsize, size);
   1409 		return;
   1410 	}
   1411 #endif
   1412 	offset = bno;
   1413 	n = pread(fsi, bf, size, offset * sectorsize);
   1414 	if (n != size) {
   1415 		printf("rdfs: read error for sector %lld: %s\n",
   1416 		    (long long)bno, strerror(errno));
   1417 		exit(34);
   1418 	}
   1419 }
   1420 
   1421 /*
   1422  * write a block to the file system
   1423  */
   1424 void
   1425 wtfs(daddr_t bno, int size, void *bf)
   1426 {
   1427 	int n;
   1428 	off_t offset;
   1429 
   1430 	if (Nflag)
   1431 		return;
   1432 #ifdef MFS
   1433 	if (mfs) {
   1434 		memmove(membase + bno * sectorsize, bf, size);
   1435 		return;
   1436 	}
   1437 #endif
   1438 	offset = bno;
   1439 	n = pwrite(fso, bf, size, offset * sectorsize);
   1440 	if (n != size) {
   1441 		printf("wtfs: write error for sector %lld: %s\n",
   1442 		    (long long)bno, strerror(errno));
   1443 		exit(36);
   1444 	}
   1445 }
   1446 
   1447 /*
   1448  * check if a block is available
   1449  */
   1450 int
   1451 isblock(struct fs *fs, unsigned char *cp, int h)
   1452 {
   1453 	unsigned char mask;
   1454 
   1455 	switch (fs->fs_fragshift) {
   1456 	case 3:
   1457 		return (cp[h] == 0xff);
   1458 	case 2:
   1459 		mask = 0x0f << ((h & 0x1) << 2);
   1460 		return ((cp[h >> 1] & mask) == mask);
   1461 	case 1:
   1462 		mask = 0x03 << ((h & 0x3) << 1);
   1463 		return ((cp[h >> 2] & mask) == mask);
   1464 	case 0:
   1465 		mask = 0x01 << (h & 0x7);
   1466 		return ((cp[h >> 3] & mask) == mask);
   1467 	default:
   1468 #ifdef STANDALONE
   1469 		printf("isblock bad fs_fragshift %d\n", fs->fs_fragshift);
   1470 #else
   1471 		fprintf(stderr, "isblock bad fs_fragshift %d\n",
   1472 		    fs->fs_fragshift);
   1473 #endif
   1474 		return (0);
   1475 	}
   1476 }
   1477 
   1478 /*
   1479  * take a block out of the map
   1480  */
   1481 void
   1482 clrblock(struct fs *fs, unsigned char *cp, int h)
   1483 {
   1484 	switch ((fs)->fs_fragshift) {
   1485 	case 3:
   1486 		cp[h] = 0;
   1487 		return;
   1488 	case 2:
   1489 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
   1490 		return;
   1491 	case 1:
   1492 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
   1493 		return;
   1494 	case 0:
   1495 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
   1496 		return;
   1497 	default:
   1498 #ifdef STANDALONE
   1499 		printf("clrblock bad fs_fragshift %d\n", fs->fs_fragshift);
   1500 #else
   1501 		fprintf(stderr, "clrblock bad fs_fragshift %d\n",
   1502 		    fs->fs_fragshift);
   1503 #endif
   1504 		return;
   1505 	}
   1506 }
   1507 
   1508 /*
   1509  * put a block into the map
   1510  */
   1511 void
   1512 setblock(struct fs *fs, unsigned char *cp, int h)
   1513 {
   1514 	switch (fs->fs_fragshift) {
   1515 	case 3:
   1516 		cp[h] = 0xff;
   1517 		return;
   1518 	case 2:
   1519 		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
   1520 		return;
   1521 	case 1:
   1522 		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
   1523 		return;
   1524 	case 0:
   1525 		cp[h >> 3] |= (0x01 << (h & 0x7));
   1526 		return;
   1527 	default:
   1528 #ifdef STANDALONE
   1529 		printf("setblock bad fs_frag %d\n", fs->fs_fragshift);
   1530 #else
   1531 		fprintf(stderr, "setblock bad fs_fragshift %d\n",
   1532 		    fs->fs_fragshift);
   1533 #endif
   1534 		return;
   1535 	}
   1536 }
   1537 
   1538 /* copy a direntry to a buffer, in fs byte order */
   1539 static void
   1540 copy_dir(struct direct *dir, struct direct *dbuf)
   1541 {
   1542 	memcpy(dbuf, dir, UFS_DIRSIZ(Oflag == 0, dir, 0));
   1543 	if (needswap) {
   1544 		dbuf->d_ino = bswap32(dir->d_ino);
   1545 		dbuf->d_reclen = bswap16(dir->d_reclen);
   1546 		if (Oflag == 0)
   1547 			((struct odirect*)dbuf)->d_namlen =
   1548 				bswap16(((struct odirect*)dir)->d_namlen);
   1549 	}
   1550 }
   1551 
   1552 static int
   1553 ilog2(int val)
   1554 {
   1555 	u_int n;
   1556 
   1557 	for (n = 0; n < sizeof(n) * CHAR_BIT; n++)
   1558 		if (1 << n == val)
   1559 			return (n);
   1560 	errx(1, "ilog2: %d is not a power of 2\n", val);
   1561 }
   1562 
   1563 static void
   1564 zap_old_sblock(int sblkoff)
   1565 {
   1566 	static int cg0_data;
   1567 	uint32_t oldfs[SBLOCKSIZE / 4];
   1568 	static const struct fsm {
   1569 		uint32_t	offset;
   1570 		uint32_t	magic;
   1571 		uint32_t	mask;
   1572 	} fs_magics[] = {
   1573 		{offsetof(struct fs, fs_magic)/4, FS_UFS1_MAGIC, ~0u},
   1574 		{offsetof(struct fs, fs_magic)/4, FS_UFS2_MAGIC, ~0u},
   1575 		{0, 0x70162, ~0u},		/* LFS_MAGIC */
   1576 		{14, 0xef53, 0xffff},		/* EXT2FS (little) */
   1577 		{14, 0xef530000, 0xffff0000},	/* EXT2FS (big) */
   1578 		{.offset = ~0u},
   1579 	};
   1580 	const struct fsm *fsm;
   1581 
   1582 	if (Nflag)
   1583 		return;
   1584 
   1585 	if (sblkoff == 0)	/* Why did UFS2 add support for this?  sigh. */
   1586 		return;
   1587 
   1588 	if (cg0_data == 0)
   1589 		/* For FFSv1 this could include all the inodes. */
   1590 		cg0_data = cgsblock(&sblock, 0) * sblock.fs_fsize + iobufsize;
   1591 
   1592 	/* Ignore anything that is beyond our filesystem */
   1593 	if ((sblkoff + SBLOCKSIZE)/sectorsize >= fssize)
   1594 		return;
   1595 	/* Zero anything inside our filesystem... */
   1596 	if (sblkoff >= sblock.fs_sblockloc) {
   1597 		/* ...unless we will write that area anyway */
   1598 		if (sblkoff >= cg0_data)
   1599 			wtfs(sblkoff / sectorsize,
   1600 			    roundup(sizeof sblock, sectorsize), iobuf);
   1601 		return;
   1602 	}
   1603 
   1604 	/* The sector might contain boot code, so we must validate it */
   1605 	rdfs(sblkoff/sectorsize, sizeof oldfs, &oldfs);
   1606 	for (fsm = fs_magics; ; fsm++) {
   1607 		uint32_t v;
   1608 		if (fsm->mask == 0)
   1609 			return;
   1610 		v = oldfs[fsm->offset];
   1611 		if ((v & fsm->mask) == fsm->magic ||
   1612 		    (bswap32(v) & fsm->mask) == fsm->magic)
   1613 			break;
   1614 	}
   1615 
   1616 	/* Just zap the magic number */
   1617 	oldfs[fsm->offset] = 0;
   1618 	wtfs(sblkoff/sectorsize, sizeof oldfs, &oldfs);
   1619 }
   1620 
   1621 
   1622 #ifdef MFS
   1623 /*
   1624  * Internal version of malloc that trims the requested size if not enough
   1625  * memory is available.
   1626  */
   1627 static void *
   1628 mkfs_malloc(size_t size)
   1629 {
   1630 	u_long pgsz;
   1631 	caddr_t *memory, *extra;
   1632 	size_t exsize = 128 * 1024;
   1633 
   1634 	if (size == 0)
   1635 		return (NULL);
   1636 
   1637 	pgsz = getpagesize() - 1;
   1638 	size = (size + pgsz) &~ pgsz;
   1639 
   1640 	/* try to map requested size */
   1641 	memory = mmap(0, size, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
   1642 	    -1, 0);
   1643 	if (memory == MAP_FAILED)
   1644 		return NULL;
   1645 
   1646 	/* try to map something extra */
   1647 	extra = mmap(0, exsize, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
   1648 	    -1, 0);
   1649 	munmap(extra, exsize);
   1650 
   1651 	/* if extra memory couldn't be mapped, reduce original request accordingly */
   1652 	if (extra == MAP_FAILED) {
   1653 		munmap(memory, size);
   1654 		size -= exsize;
   1655 		memory = mmap(0, size, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
   1656 		    -1, 0);
   1657 		if (memory == MAP_FAILED)
   1658 			return NULL;
   1659 	}
   1660 
   1661 	return memory;
   1662 }
   1663 #endif	/* MFS */
   1664