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mkfs.c revision 1.110.2.3
      1 /*	$NetBSD: mkfs.c,v 1.110.2.3 2014/05/22 11:37:30 yamt 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 1.110.2.3 2014/05/22 11:37:30 yamt 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 (at) 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