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mkfs.c revision 1.130
      1 /*	$NetBSD: mkfs.c,v 1.130 2020/08/20 15:54:11 riastradh 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 1.130 2020/08/20 15:54:11 riastradh 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 union Buffer;
    114 static int makedir(union Buffer *, struct direct *, int);
    115 static daddr_t alloc(int, int);
    116 static void iput(union dinode *, ino_t);
    117 static void rdfs(daddr_t, int, void *);
    118 static void wtfs(daddr_t, int, void *);
    119 static int isblock(struct fs *, unsigned char *, int);
    120 static void clrblock(struct fs *, unsigned char *, int);
    121 static void setblock(struct fs *, unsigned char *, int);
    122 static int ilog2(int);
    123 static void zap_old_sblock(int);
    124 #ifdef MFS
    125 static void *mkfs_malloc(size_t size);
    126 #endif
    127 
    128 /*
    129  * make file system for cylinder-group style file systems
    130  */
    131 #define	UMASK		0755
    132 
    133 union {
    134 	struct fs fs;
    135 	char data[SBLOCKSIZE];
    136 } *fsun;
    137 #define	sblock	fsun->fs
    138 
    139 union Buffer {
    140 	struct quota2_header q2h;
    141 	char data[MAXBSIZE];
    142 };
    143 
    144 struct	csum *fscs_0;		/* first block of cylinder summaries */
    145 struct	csum *fscs_next;	/* place for next summary */
    146 struct	csum *fscs_end;		/* end of summary buffer */
    147 struct	csum *fscs_reset;	/* place for next summary after write */
    148 uint	fs_csaddr;		/* fragment number to write to */
    149 
    150 union {
    151 	struct cg cg;
    152 	char pad[MAXBSIZE];
    153 } *cgun;
    154 #define	acg	cgun->cg
    155 
    156 #define DIP(dp, field) \
    157 	((sblock.fs_magic == FS_UFS1_MAGIC) ? \
    158 	(dp)->dp1.di_##field : (dp)->dp2.di_##field)
    159 
    160 #define EXT2FS_SBOFF	1024	/* XXX: SBOFF in <ufs/ext2fs/ext2fs.h> */
    161 
    162 char *iobuf;
    163 int iobufsize;			/* size to end of 2nd inode block */
    164 int iobuf_memsize;		/* Actual buffer size */
    165 
    166 int	fsi, fso;
    167 
    168 static void
    169 fserr(int num)
    170 {
    171 #ifdef GARBAGE
    172 	extern int Gflag;
    173 
    174 	if (Gflag)
    175 		return;
    176 #endif
    177 	exit(num);
    178 }
    179 
    180 void
    181 mkfs(const char *fsys, int fi, int fo,
    182     mode_t mfsmode, uid_t mfsuid, gid_t mfsgid)
    183 {
    184 	uint fragsperinodeblk, ncg, u;
    185 	uint cgzero;
    186 	uint64_t inodeblks, cgall;
    187 	int32_t cylno, i, csfrags;
    188 	int inodes_per_cg;
    189 	struct timeval tv;
    190 	long long sizepb;
    191 	int len, col, delta, fld_width, max_cols;
    192 	struct winsize winsize;
    193 
    194 #ifndef STANDALONE
    195 	gettimeofday(&tv, NULL);
    196 #endif
    197 #ifdef MFS
    198 	if (mfs && !Nflag) {
    199 		if ((membase = mkfs_malloc(fssize * sectorsize)) == NULL)
    200 			exit(12);
    201 	}
    202 #endif
    203 	if ((fsun = aligned_alloc(DEV_BSIZE, sizeof(*fsun))) == NULL)
    204 		exit(12);
    205 	memset(fsun, 0, sizeof(*fsun));
    206 	if ((cgun = aligned_alloc(DEV_BSIZE, sizeof(*cgun))) == NULL)
    207 		exit(12);
    208 	memset(cgun, 0, sizeof(*cgun));
    209 
    210 	fsi = fi;
    211 	fso = fo;
    212 	if (Oflag == 0) {
    213 		sblock.fs_old_inodefmt = FS_42INODEFMT;
    214 		sblock.fs_maxsymlinklen = 0;
    215 		sblock.fs_old_flags = 0;
    216 	} else {
    217 		sblock.fs_old_inodefmt = FS_44INODEFMT;
    218 		sblock.fs_maxsymlinklen = (Oflag == 1 ? UFS1_MAXSYMLINKLEN :
    219 		    UFS2_MAXSYMLINKLEN);
    220 		sblock.fs_old_flags = FS_FLAGS_UPDATED;
    221 		if (isappleufs)
    222 			sblock.fs_old_flags = 0;
    223 		sblock.fs_flags = 0;
    224 	}
    225 
    226 	/*
    227 	 * collect and verify the filesystem density info
    228 	 */
    229 	sblock.fs_avgfilesize = avgfilesize;
    230 	sblock.fs_avgfpdir = avgfpdir;
    231 	if (sblock.fs_avgfilesize <= 0) {
    232 		printf("illegal expected average file size %d\n",
    233 		    sblock.fs_avgfilesize);
    234 		fserr(14);
    235 	}
    236 	if (sblock.fs_avgfpdir <= 0) {
    237 		printf("illegal expected number of files per directory %d\n",
    238 		    sblock.fs_avgfpdir);
    239 		fserr(15);
    240 	}
    241 	/*
    242 	 * collect and verify the block and fragment sizes
    243 	 */
    244 	sblock.fs_bsize = bsize;
    245 	sblock.fs_fsize = fsize;
    246 	if (!powerof2(sblock.fs_bsize)) {
    247 		printf("block size must be a power of 2, not %d\n",
    248 		    sblock.fs_bsize);
    249 		fserr(16);
    250 	}
    251 	if (!powerof2(sblock.fs_fsize)) {
    252 		printf("fragment size must be a power of 2, not %d\n",
    253 		    sblock.fs_fsize);
    254 		fserr(17);
    255 	}
    256 	if (sblock.fs_fsize < sectorsize) {
    257 		printf("fragment size %d is too small, minimum is %d\n",
    258 		    sblock.fs_fsize, sectorsize);
    259 		fserr(18);
    260 	}
    261 	if (sblock.fs_bsize < MINBSIZE) {
    262 		printf("block size %d is too small, minimum is %d\n",
    263 		    sblock.fs_bsize, MINBSIZE);
    264 		fserr(19);
    265 	}
    266 	if (sblock.fs_bsize > MAXBSIZE) {
    267 		printf("block size %d is too large, maximum is %d\n",
    268 		    sblock.fs_bsize, MAXBSIZE);
    269 		fserr(19);
    270 	}
    271 	if (sblock.fs_bsize < sblock.fs_fsize) {
    272 		printf("block size (%d) cannot be smaller than fragment size (%d)\n",
    273 		    sblock.fs_bsize, sblock.fs_fsize);
    274 		fserr(20);
    275 	}
    276 
    277 	if (maxbsize < bsize || !powerof2(maxbsize)) {
    278 		sblock.fs_maxbsize = sblock.fs_bsize;
    279 	} else if (sblock.fs_maxbsize > FS_MAXCONTIG * sblock.fs_bsize) {
    280 		sblock.fs_maxbsize = FS_MAXCONTIG * sblock.fs_bsize;
    281 	} else {
    282 		sblock.fs_maxbsize = maxbsize;
    283 	}
    284 	sblock.fs_maxcontig = maxcontig;
    285 	if (sblock.fs_maxcontig < sblock.fs_maxbsize / sblock.fs_bsize) {
    286 		sblock.fs_maxcontig = sblock.fs_maxbsize / sblock.fs_bsize;
    287 		if (verbosity > 0)
    288 			printf("Maxcontig raised to %d\n", sblock.fs_maxbsize);
    289 	}
    290 	if (sblock.fs_maxcontig > 1)
    291 		sblock.fs_contigsumsize = MIN(sblock.fs_maxcontig,FS_MAXCONTIG);
    292 
    293 	sblock.fs_bmask = ~(sblock.fs_bsize - 1);
    294 	sblock.fs_fmask = ~(sblock.fs_fsize - 1);
    295 	sblock.fs_qbmask = ~sblock.fs_bmask;
    296 	sblock.fs_qfmask = ~sblock.fs_fmask;
    297 	for (sblock.fs_bshift = 0, i = sblock.fs_bsize; i > 1; i >>= 1)
    298 		sblock.fs_bshift++;
    299 	for (sblock.fs_fshift = 0, i = sblock.fs_fsize; i > 1; i >>= 1)
    300 		sblock.fs_fshift++;
    301 	sblock.fs_frag = ffs_numfrags(&sblock, sblock.fs_bsize);
    302 	for (sblock.fs_fragshift = 0, i = sblock.fs_frag; i > 1; i >>= 1)
    303 		sblock.fs_fragshift++;
    304 	if (sblock.fs_frag > MAXFRAG) {
    305 		printf("fragment size %d is too small, "
    306 			"minimum with block size %d is %d\n",
    307 		    sblock.fs_fsize, sblock.fs_bsize,
    308 		    sblock.fs_bsize / MAXFRAG);
    309 		fserr(21);
    310 	}
    311 	sblock.fs_fsbtodb = ilog2(sblock.fs_fsize / sectorsize);
    312 	sblock.fs_size = FFS_DBTOFSB(&sblock, fssize);
    313 	if (Oflag <= 1) {
    314 		if ((uint64_t)sblock.fs_size >= 1ull << 31) {
    315 			printf("Too many fragments (0x%" PRIx64
    316 			    ") for a FFSv1 filesystem\n", sblock.fs_size);
    317 			fserr(22);
    318 		}
    319 		sblock.fs_magic = FS_UFS1_MAGIC;
    320 		sblock.fs_sblockloc = SBLOCK_UFS1;
    321 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int32_t);
    322 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs1_dinode);
    323 		sblock.fs_old_cgoffset = 0;
    324 		sblock.fs_old_cgmask = 0xffffffff;
    325 		sblock.fs_old_size = sblock.fs_size;
    326 		sblock.fs_old_rotdelay = 0;
    327 		sblock.fs_old_rps = 60;
    328 		sblock.fs_old_nspf = sblock.fs_fsize / sectorsize;
    329 		sblock.fs_old_cpg = 1;
    330 		sblock.fs_old_interleave = 1;
    331 		sblock.fs_old_trackskew = 0;
    332 		sblock.fs_old_cpc = 0;
    333 		sblock.fs_old_postblformat = FS_DYNAMICPOSTBLFMT;
    334 		sblock.fs_old_nrpos = 1;
    335 	} else {
    336 		sblock.fs_magic = FS_UFS2_MAGIC;
    337 		sblock.fs_sblockloc = SBLOCK_UFS2;
    338 		sblock.fs_nindir = sblock.fs_bsize / sizeof(int64_t);
    339 		sblock.fs_inopb = sblock.fs_bsize / sizeof(struct ufs2_dinode);
    340 	}
    341 
    342 	sblock.fs_sblkno =
    343 	    roundup(howmany(sblock.fs_sblockloc + SBLOCKSIZE, sblock.fs_fsize),
    344 		sblock.fs_frag);
    345 	sblock.fs_cblkno = (daddr_t)(sblock.fs_sblkno +
    346 	    roundup(howmany(SBLOCKSIZE, sblock.fs_fsize), sblock.fs_frag));
    347 	sblock.fs_iblkno = sblock.fs_cblkno + sblock.fs_frag;
    348 	sblock.fs_maxfilesize = sblock.fs_bsize * UFS_NDADDR - 1;
    349 	for (sizepb = sblock.fs_bsize, i = 0; i < UFS_NIADDR; i++) {
    350 		sizepb *= FFS_NINDIR(&sblock);
    351 		sblock.fs_maxfilesize += sizepb;
    352 	}
    353 
    354 	/*
    355 	 * Calculate the number of blocks to put into each cylinder group.
    356 	 *
    357 	 * The cylinder group size is limited because the data structure
    358 	 * must fit into a single block.
    359 	 * We try to have as few cylinder groups as possible, with a proviso
    360 	 * that we create at least MINCYLGRPS (==4) except for small
    361 	 * filesystems.
    362 	 *
    363 	 * This algorithm works out how many blocks of inodes would be
    364 	 * needed to fill the entire volume at the specified density.
    365 	 * It then looks at how big the 'cylinder block' would have to
    366 	 * be and, assuming that it is linearly related to the number
    367 	 * of inodes and blocks how many cylinder groups are needed to
    368 	 * keep the cylinder block below the filesystem block size.
    369 	 *
    370 	 * The cylinder groups are then all created with the average size.
    371 	 *
    372 	 * Space taken by the red tape on cylinder groups other than the
    373 	 * first is ignored.
    374 	 */
    375 
    376 	/* There must be space for 1 inode block and 2 data blocks */
    377 	if (sblock.fs_size < sblock.fs_iblkno + 3 * sblock.fs_frag) {
    378 		printf("Filesystem size %lld < minimum size of %d\n",
    379 		    (long long)sblock.fs_size, sblock.fs_iblkno + 3 * sblock.fs_frag);
    380 		fserr(23);
    381 	}
    382 	if (num_inodes != 0)
    383 		inodeblks = howmany(num_inodes, FFS_INOPB(&sblock));
    384 	else {
    385 		/*
    386 		 * Calculate 'per inode block' so we can allocate less than
    387 		 * 1 fragment per inode - useful for /dev.
    388 		 */
    389 		fragsperinodeblk = MAX(ffs_numfrags(&sblock,
    390 					(uint64_t)density * FFS_INOPB(&sblock)), 1);
    391 		inodeblks = (sblock.fs_size - sblock.fs_iblkno) /
    392 			(sblock.fs_frag + fragsperinodeblk);
    393 	}
    394 	if (inodeblks == 0)
    395 		inodeblks = 1;
    396 	/* Ensure that there are at least 2 data blocks (or we fail below) */
    397 	if (inodeblks > (uint64_t)(sblock.fs_size - sblock.fs_iblkno)/sblock.fs_frag - 2)
    398 		inodeblks = (sblock.fs_size-sblock.fs_iblkno)/sblock.fs_frag-2;
    399 	/* Even UFS2 limits number of inodes to 2^31 (fs_ipg is int32_t) */
    400 	if (inodeblks * FFS_INOPB(&sblock) >= 1ull << 31)
    401 		inodeblks = ((1ull << 31) - NBBY) / FFS_INOPB(&sblock);
    402 	/*
    403 	 * See what would happen if we tried to use 1 cylinder group.
    404 	 * Assume space linear, so work out number of cylinder groups needed.
    405 	 */
    406 	cgzero = CGSIZE_IF(&sblock, 0, 0);
    407 	cgall = CGSIZE_IF(&sblock, inodeblks * FFS_INOPB(&sblock), sblock.fs_size);
    408 	ncg = howmany(cgall - cgzero, sblock.fs_bsize - cgzero);
    409 	if (ncg < MINCYLGRPS) {
    410 		/*
    411 		 * We would like to allocate MINCLYGRPS cylinder groups,
    412 		 * but for small file sytems (especially ones with a lot
    413 		 * of inodes) this is not desirable (or possible).
    414 		 */
    415 		u = sblock.fs_size / 2 / (sblock.fs_iblkno +
    416 						inodeblks * sblock.fs_frag);
    417 		if (u > ncg)
    418 			ncg = u;
    419 		if (ncg > MINCYLGRPS)
    420 			ncg = MINCYLGRPS;
    421 		if (ncg > inodeblks)
    422 			ncg = inodeblks;
    423 	}
    424 	/*
    425 	 * Put an equal number of blocks in each cylinder group.
    426 	 * Round up so we don't have more fragments in the last CG than
    427 	 * the earlier ones (does that matter?), but kill a block if the
    428 	 * CGSIZE becomes too big (only happens if there are a lot of CGs).
    429 	 */
    430 	sblock.fs_fpg = roundup(howmany(sblock.fs_size, ncg), sblock.fs_frag);
    431 	/* Round up the fragments/group so the bitmap bytes are full */
    432 	sblock.fs_fpg = roundup(sblock.fs_fpg, NBBY);
    433 	inodes_per_cg = ((inodeblks - 1) / ncg + 1) * FFS_INOPB(&sblock);
    434 
    435 	i = CGSIZE_IF(&sblock, inodes_per_cg, sblock.fs_fpg);
    436 	if (i > sblock.fs_bsize) {
    437 		sblock.fs_fpg -= (i - sblock.fs_bsize) * NBBY;
    438 		/* ... and recalculate how many cylinder groups we now need */
    439 		ncg = howmany(sblock.fs_size, sblock.fs_fpg);
    440 		inodes_per_cg = ((inodeblks - 1) / ncg + 1) * FFS_INOPB(&sblock);
    441 	}
    442 	sblock.fs_ipg = inodes_per_cg;
    443 	/* Sanity check on our sums... */
    444 	if ((int)CGSIZE(&sblock) > sblock.fs_bsize) {
    445 		printf("CGSIZE miscalculated %d > %d\n",
    446 		    (int)CGSIZE(&sblock), sblock.fs_bsize);
    447 		fserr(24);
    448 	}
    449 
    450 	sblock.fs_dblkno = sblock.fs_iblkno + sblock.fs_ipg / FFS_INOPF(&sblock);
    451 	/* Check that the last cylinder group has enough space for the inodes */
    452 	i = sblock.fs_size - sblock.fs_fpg * (ncg - 1ull);
    453 	if (i < sblock.fs_dblkno) {
    454 		/*
    455 		 * Since we make all the cylinder groups the same size, the
    456 		 * last will only be small if there are a large number of
    457 		 * cylinder groups. If we pull even a fragment from each
    458 		 * of the other groups then the last CG will be overfull.
    459 		 * So we just kill the last CG.
    460 		 */
    461 		ncg--;
    462 		sblock.fs_size -= i;
    463 	}
    464 	sblock.fs_ncg = ncg;
    465 
    466 	sblock.fs_cgsize = ffs_fragroundup(&sblock, CGSIZE(&sblock));
    467 	if (Oflag <= 1) {
    468 		sblock.fs_old_spc = sblock.fs_fpg * sblock.fs_old_nspf;
    469 		sblock.fs_old_nsect = sblock.fs_old_spc;
    470 		sblock.fs_old_npsect = sblock.fs_old_spc;
    471 		sblock.fs_old_ncyl = sblock.fs_ncg;
    472 	}
    473 
    474 	/*
    475 	 * Cylinder group summary information for each cylinder is written
    476 	 * into the first cylinder group.
    477 	 * Write this fragment by fragment, but doing the first CG last
    478 	 * (after we've taken stuff off for the structure itself and the
    479 	 * root directory.
    480 	 */
    481 	sblock.fs_csaddr = cgdmin(&sblock, 0);
    482 	sblock.fs_cssize =
    483 	    ffs_fragroundup(&sblock, sblock.fs_ncg * sizeof(struct csum));
    484 	if (512 % sizeof *fscs_0)
    485 		errx(1, "cylinder group summary doesn't fit in sectors");
    486 	fscs_0 = mmap(0, 2 * sblock.fs_fsize, PROT_READ|PROT_WRITE,
    487 			MAP_ANON|MAP_PRIVATE, -1, 0);
    488 	if (fscs_0 == MAP_FAILED)
    489 		exit(39);
    490 	memset(fscs_0, 0, 2 * sblock.fs_fsize);
    491 	fs_csaddr = sblock.fs_csaddr;
    492 	fscs_next = fscs_0;
    493 	fscs_end = (void *)((char *)fscs_0 + 2 * sblock.fs_fsize);
    494 	fscs_reset = (void *)((char *)fscs_0 + sblock.fs_fsize);
    495 	/*
    496 	 * fill in remaining fields of the super block
    497 	 */
    498 	sblock.fs_sbsize = ffs_fragroundup(&sblock, sizeof(struct fs));
    499 	if (sblock.fs_sbsize > SBLOCKSIZE)
    500 		sblock.fs_sbsize = SBLOCKSIZE;
    501 	sblock.fs_minfree = minfree;
    502 	sblock.fs_maxcontig = maxcontig;
    503 	sblock.fs_maxbpg = maxbpg;
    504 	sblock.fs_optim = opt;
    505 	sblock.fs_cgrotor = 0;
    506 	sblock.fs_pendingblocks = 0;
    507 	sblock.fs_pendinginodes = 0;
    508 	sblock.fs_cstotal.cs_ndir = 0;
    509 	sblock.fs_cstotal.cs_nbfree = 0;
    510 	sblock.fs_cstotal.cs_nifree = 0;
    511 	sblock.fs_cstotal.cs_nffree = 0;
    512 	sblock.fs_fmod = 0;
    513 	sblock.fs_ronly = 0;
    514 	sblock.fs_state = 0;
    515 	sblock.fs_clean = FS_ISCLEAN;
    516 	sblock.fs_ronly = 0;
    517 	sblock.fs_id[0] = (long)tv.tv_sec;	/* XXXfvdl huh? */
    518 	sblock.fs_id[1] = arc4random() & INT32_MAX;
    519 	sblock.fs_fsmnt[0] = '\0';
    520 	csfrags = howmany(sblock.fs_cssize, sblock.fs_fsize);
    521 	sblock.fs_dsize = sblock.fs_size - sblock.fs_sblkno -
    522 	    sblock.fs_ncg * (sblock.fs_dblkno - sblock.fs_sblkno);
    523 	sblock.fs_cstotal.cs_nbfree =
    524 	    ffs_fragstoblks(&sblock, sblock.fs_dsize) -
    525 	    howmany(csfrags, sblock.fs_frag);
    526 	sblock.fs_cstotal.cs_nffree =
    527 	    ffs_fragnum(&sblock, sblock.fs_size) +
    528 	    (ffs_fragnum(&sblock, csfrags) > 0 ?
    529 	    sblock.fs_frag - ffs_fragnum(&sblock, csfrags) : 0);
    530 	sblock.fs_cstotal.cs_nifree = sblock.fs_ncg * sblock.fs_ipg - UFS_ROOTINO;
    531 	sblock.fs_cstotal.cs_ndir = 0;
    532 	sblock.fs_dsize -= csfrags;
    533 	sblock.fs_time = tv.tv_sec;
    534 	if (Oflag <= 1) {
    535 		sblock.fs_old_time = tv.tv_sec;
    536 		sblock.fs_old_dsize = sblock.fs_dsize;
    537 		sblock.fs_old_csaddr = sblock.fs_csaddr;
    538 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
    539 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
    540 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
    541 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
    542 	}
    543 	/* add quota data in superblock */
    544 	if (quotas) {
    545 		sblock.fs_flags |= FS_DOQUOTA2;
    546 		sblock.fs_quota_magic = Q2_HEAD_MAGIC;
    547 		sblock.fs_quota_flags = quotas;
    548 	}
    549 	/*
    550 	 * Dump out summary information about file system.
    551 	 */
    552 	if (verbosity > 0) {
    553 #define	B2MBFACTOR (1 / (1024.0 * 1024.0))
    554 		printf("%s: %.1fMB (%lld sectors) block size %d, "
    555 		       "fragment size %d\n",
    556 		    fsys, (float)sblock.fs_size * sblock.fs_fsize * B2MBFACTOR,
    557 		    (long long)FFS_FSBTODB(&sblock, sblock.fs_size),
    558 		    sblock.fs_bsize, sblock.fs_fsize);
    559 		printf("\tusing %d cylinder groups of %.2fMB, %d blks, "
    560 		       "%d inodes.\n",
    561 		    sblock.fs_ncg,
    562 		    (float)sblock.fs_fpg * sblock.fs_fsize * B2MBFACTOR,
    563 		    sblock.fs_fpg / sblock.fs_frag, sblock.fs_ipg);
    564 #undef B2MBFACTOR
    565 	}
    566 
    567 	/*
    568 	 * allocate space for superblock, cylinder group map, and
    569 	 * two sets of inode blocks.
    570 	 */
    571 	if (sblock.fs_bsize < SBLOCKSIZE)
    572 		iobufsize = SBLOCKSIZE + 3 * sblock.fs_bsize;
    573 	else
    574 		iobufsize = 4 * sblock.fs_bsize;
    575 	iobuf_memsize = iobufsize;
    576 	if (!mfs && sblock.fs_magic == FS_UFS1_MAGIC) {
    577 		/* A larger buffer so we can write multiple inode blks */
    578 		iobuf_memsize += 14 * sblock.fs_bsize;
    579 	}
    580 	for (;;) {
    581 		iobuf = mmap(0, iobuf_memsize, PROT_READ|PROT_WRITE,
    582 				MAP_ANON|MAP_PRIVATE, -1, 0);
    583 		if (iobuf != MAP_FAILED)
    584 			break;
    585 		if (iobuf_memsize != iobufsize) {
    586 			/* Try again with the smaller size */
    587 			iobuf_memsize = iobufsize;
    588 			continue;
    589 		}
    590 		printf("Cannot allocate I/O buffer\n");
    591 		exit(38);
    592 	}
    593 	memset(iobuf, 0, iobuf_memsize);
    594 
    595 	/*
    596 	 * We now start writing to the filesystem
    597 	 */
    598 
    599 	if (!Nflag) {
    600 		/*
    601 		 * Validate the given file system size.
    602 		 * Verify that its last block can actually be accessed.
    603 		 * Convert to file system fragment sized units.
    604 		 */
    605 		if (fssize <= 0) {
    606 			printf("preposterous size %lld\n", (long long)fssize);
    607 			fserr(13);
    608 		}
    609 		wtfs(fssize - 1, sectorsize, iobuf);
    610 
    611 		/*
    612 		 * Ensure there is nothing that looks like a filesystem
    613 		 * superbock anywhere other than where ours will be.
    614 		 * If fsck finds the wrong one all hell breaks loose!
    615 		 */
    616 		for (i = 0; ; i++) {
    617 			static const int sblocklist[] = SBLOCKSEARCH;
    618 			int sblkoff = sblocklist[i];
    619 			int sz;
    620 			if (sblkoff == -1)
    621 				break;
    622 			/* Remove main superblock */
    623 			zap_old_sblock(sblkoff);
    624 			/* and all possible locations for the first alternate */
    625 			sblkoff += SBLOCKSIZE;
    626 			for (sz = SBLOCKSIZE; sz <= 0x10000; sz <<= 1)
    627 				zap_old_sblock(roundup(sblkoff, sz));
    628 		}
    629 		/*
    630 		 * Also zap possible Ext2fs magic leftover to prevent
    631 		 * kernel vfs_mountroot() and bootloaders from mis-recognizing
    632 		 * this file system as Ext2fs.
    633 		 */
    634 		zap_old_sblock(EXT2FS_SBOFF);
    635 
    636 #ifndef NO_APPLE_UFS
    637 		if (isappleufs) {
    638 			struct appleufslabel appleufs __aligned(DEV_BSIZE);
    639 			ffs_appleufs_set(&appleufs, appleufs_volname,
    640 			    tv.tv_sec, 0);
    641 			wtfs(APPLEUFS_LABEL_OFFSET/sectorsize,
    642 			    APPLEUFS_LABEL_SIZE, &appleufs);
    643 		} else if (APPLEUFS_LABEL_SIZE % sectorsize == 0) {
    644 			struct appleufslabel appleufs;
    645 			/* Look for & zap any existing valid apple ufs labels */
    646 			rdfs(APPLEUFS_LABEL_OFFSET/sectorsize,
    647 			    APPLEUFS_LABEL_SIZE, &appleufs);
    648 			if (ffs_appleufs_validate(fsys, &appleufs, NULL) == 0) {
    649 				memset(&appleufs, 0, sizeof(appleufs));
    650 				wtfs(APPLEUFS_LABEL_OFFSET/sectorsize,
    651 				    APPLEUFS_LABEL_SIZE, &appleufs);
    652 			}
    653 		}
    654 #endif
    655 	}
    656 
    657 	/*
    658 	 * Make a copy of the superblock into the buffer that we will be
    659 	 * writing out in each cylinder group.
    660 	 */
    661 	memcpy(iobuf, &sblock, sizeof sblock);
    662 	if (needswap)
    663 		ffs_sb_swap(&sblock, (struct fs *)iobuf);
    664 	if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0)
    665 		memset(iobuf + offsetof(struct fs, fs_old_postbl_start),
    666 		    0xff, 256);
    667 
    668 	if (verbosity >= 3)
    669 		printf("super-block backups (for fsck_ffs -b #) at:\n");
    670 	/* If we are printing more than one line of numbers, line up columns */
    671 	fld_width = verbosity < 4 ? 1 : snprintf(NULL, 0, "%" PRIu64,
    672 		(uint64_t)FFS_FSBTODB(&sblock, cgsblock(&sblock, sblock.fs_ncg-1)));
    673 	/* Get terminal width */
    674 	if (ioctl(fileno(stdout), TIOCGWINSZ, &winsize) == 0)
    675 		max_cols = winsize.ws_col;
    676 	else
    677 		max_cols = 80;
    678 	if (Nflag && verbosity == 3)
    679 		/* Leave space to add " ..." after one row of numbers */
    680 		max_cols -= 4;
    681 #define BASE 0x10000	/* For some fixed-point maths */
    682 	col = 0;
    683 	delta = verbosity > 2 ? 0 : max_cols * BASE / sblock.fs_ncg;
    684 	for (cylno = 0; cylno < sblock.fs_ncg; cylno++) {
    685 		fflush(stdout);
    686 		initcg(cylno, &tv);
    687 		if (verbosity < 2)
    688 			continue;
    689 		if (delta > 0) {
    690 			if (Nflag)
    691 				/* No point doing dots for -N */
    692 				break;
    693 			/* Print dots scaled to end near RH margin */
    694 			for (col += delta; col > BASE; col -= BASE)
    695 				printf(".");
    696 			continue;
    697 		}
    698 		/* Print superblock numbers */
    699 		len = printf("%s%*" PRIu64 ",", col ? " " : "", fld_width,
    700 		    (uint64_t)FFS_FSBTODB(&sblock, cgsblock(&sblock, cylno)));
    701 		col += len;
    702 		if (col + len < max_cols)
    703 			/* Next number fits */
    704 			continue;
    705 		/* Next number won't fit, need a newline */
    706 		if (verbosity <= 3) {
    707 			/* Print dots for subsequent cylinder groups */
    708 			delta = sblock.fs_ncg - cylno - 1;
    709 			if (delta != 0) {
    710 				if (Nflag) {
    711 					printf(" ...");
    712 					break;
    713 				}
    714 				delta = max_cols * BASE / delta;
    715 			}
    716 		}
    717 		col = 0;
    718 		printf("\n");
    719 	}
    720 #undef BASE
    721 	if (col > 0)
    722 		printf("\n");
    723 	if (Nflag)
    724 		exit(0);
    725 
    726 	/*
    727 	 * Now construct the initial file system,
    728 	 */
    729 	if (fsinit(&tv, mfsmode, mfsuid, mfsgid) == 0 && mfs)
    730 		errx(1, "Error making filesystem");
    731 	sblock.fs_time = tv.tv_sec;
    732 	if (Oflag <= 1) {
    733 		sblock.fs_old_cstotal.cs_ndir = sblock.fs_cstotal.cs_ndir;
    734 		sblock.fs_old_cstotal.cs_nbfree = sblock.fs_cstotal.cs_nbfree;
    735 		sblock.fs_old_cstotal.cs_nifree = sblock.fs_cstotal.cs_nifree;
    736 		sblock.fs_old_cstotal.cs_nffree = sblock.fs_cstotal.cs_nffree;
    737 	}
    738 	/*
    739 	 * Write out the super-block and zeros until the first cg info
    740 	 */
    741 	i = cgsblock(&sblock, 0) * sblock.fs_fsize - sblock.fs_sblockloc;
    742 	if ((size_t)i < sizeof(sblock))
    743 		errx(1, "No space for superblock");
    744 	memcpy(iobuf, &sblock, sizeof(sblock));
    745 	memset(iobuf + sizeof(sblock), 0, i - sizeof(sblock));
    746 	if (needswap)
    747 		ffs_sb_swap(&sblock, (struct fs *)iobuf);
    748 	if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0)
    749 		memset(iobuf + offsetof(struct fs, fs_old_postbl_start),
    750 		    0xff, 256);
    751 	wtfs(sblock.fs_sblockloc / sectorsize, i, iobuf);
    752 
    753 	/* Write out first and last cylinder summary sectors */
    754 	if (needswap)
    755 		ffs_csum_swap(fscs_0, fscs_0, sblock.fs_fsize);
    756 	wtfs(FFS_FSBTODB(&sblock, sblock.fs_csaddr), sblock.fs_fsize, fscs_0);
    757 
    758 	if (fscs_next > fscs_reset) {
    759 		if (needswap)
    760 			ffs_csum_swap(fscs_reset, fscs_reset, sblock.fs_fsize);
    761 		fs_csaddr++;
    762 		wtfs(FFS_FSBTODB(&sblock, fs_csaddr), sblock.fs_fsize, fscs_reset);
    763 	}
    764 
    765 	/* mfs doesn't need these permanently allocated */
    766 	munmap(iobuf, iobuf_memsize);
    767 	munmap(fscs_0, 2 * sblock.fs_fsize);
    768 }
    769 
    770 /*
    771  * Initialize a cylinder group.
    772  */
    773 void
    774 initcg(int cylno, const struct timeval *tv)
    775 {
    776 	daddr_t cbase, dmax;
    777 	int32_t i, d, dlower, dupper, blkno;
    778 	uint32_t u;
    779 	struct ufs1_dinode *dp1;
    780 	struct ufs2_dinode *dp2;
    781 	int start;
    782 
    783 	/*
    784 	 * Determine block bounds for cylinder group.
    785 	 * Allow space for super block summary information in first
    786 	 * cylinder group.
    787 	 */
    788 	cbase = cgbase(&sblock, cylno);
    789 	dmax = cbase + sblock.fs_fpg;
    790 	if (dmax > sblock.fs_size)
    791 		dmax = sblock.fs_size;
    792 	dlower = cgsblock(&sblock, cylno) - cbase;
    793 	dupper = cgdmin(&sblock, cylno) - cbase;
    794 	if (cylno == 0) {
    795 		dupper += howmany(sblock.fs_cssize, sblock.fs_fsize);
    796 		if (dupper >= cgstart(&sblock, cylno + 1)) {
    797 			printf("\rToo many cylinder groups to fit summary "
    798 				"information into first cylinder group\n");
    799 			fserr(40);
    800 		}
    801 	}
    802 	memset(&acg, 0, sblock.fs_cgsize);
    803 	acg.cg_magic = CG_MAGIC;
    804 	acg.cg_cgx = cylno;
    805 	acg.cg_ndblk = dmax - cbase;
    806 	if (sblock.fs_contigsumsize > 0)
    807 		acg.cg_nclusterblks = acg.cg_ndblk >> sblock.fs_fragshift;
    808 	start = &acg.cg_space[0] - (u_char *)(&acg.cg_firstfield);
    809 	if (Oflag == 2) {
    810 		acg.cg_time = tv->tv_sec;
    811 		acg.cg_niblk = sblock.fs_ipg;
    812 		acg.cg_initediblk = sblock.fs_ipg < 2 * FFS_INOPB(&sblock) ?
    813 		    sblock.fs_ipg : 2 * FFS_INOPB(&sblock);
    814 		acg.cg_iusedoff = start;
    815 	} else {
    816 		acg.cg_old_ncyl = sblock.fs_old_cpg;
    817 		if ((sblock.fs_old_flags & FS_FLAGS_UPDATED) == 0 &&
    818 		    (cylno == sblock.fs_ncg - 1))
    819 			acg.cg_old_ncyl =
    820 			    sblock.fs_old_ncyl % sblock.fs_old_cpg;
    821 		acg.cg_old_time = tv->tv_sec;
    822 		acg.cg_old_niblk = sblock.fs_ipg;
    823 		acg.cg_old_btotoff = start;
    824 		acg.cg_old_boff = acg.cg_old_btotoff +
    825 		    sblock.fs_old_cpg * sizeof(int32_t);
    826 		acg.cg_iusedoff = acg.cg_old_boff +
    827 		    sblock.fs_old_cpg * sizeof(u_int16_t);
    828 	}
    829 	acg.cg_freeoff = acg.cg_iusedoff + howmany(sblock.fs_ipg, CHAR_BIT);
    830 	if (sblock.fs_contigsumsize <= 0) {
    831 		acg.cg_nextfreeoff = acg.cg_freeoff +
    832 		   howmany(sblock.fs_fpg, CHAR_BIT);
    833 	} else {
    834 		acg.cg_clustersumoff = acg.cg_freeoff +
    835 		    howmany(sblock.fs_fpg, CHAR_BIT) - sizeof(int32_t);
    836 		if (isappleufs) {
    837 			/* Apple PR2216969 gives rationale for this change.
    838 			 * I believe they were mistaken, but we need to
    839 			 * duplicate it for compatibility.  -- dbj (at) NetBSD.org
    840 			 */
    841 			acg.cg_clustersumoff += sizeof(int32_t);
    842 		}
    843 		acg.cg_clustersumoff =
    844 		    roundup(acg.cg_clustersumoff, sizeof(int32_t));
    845 		acg.cg_clusteroff = acg.cg_clustersumoff +
    846 		    (sblock.fs_contigsumsize + 1) * sizeof(int32_t);
    847 		acg.cg_nextfreeoff = acg.cg_clusteroff +
    848 		    howmany(ffs_fragstoblks(&sblock, sblock.fs_fpg), CHAR_BIT);
    849 	}
    850 	if (acg.cg_nextfreeoff > sblock.fs_cgsize) {
    851 		printf("Panic: cylinder group too big\n");
    852 		fserr(37);
    853 	}
    854 	acg.cg_cs.cs_nifree += sblock.fs_ipg;
    855 	if (cylno == 0)
    856 		for (u = 0; u < UFS_ROOTINO; u++) {
    857 			setbit(cg_inosused(&acg, 0), u);
    858 			acg.cg_cs.cs_nifree--;
    859 		}
    860 	if (cylno > 0) {
    861 		/*
    862 		 * In cylno 0, beginning space is reserved
    863 		 * for boot and super blocks.
    864 		 */
    865 		for (d = 0, blkno = 0; d < dlower;) {
    866 			setblock(&sblock, cg_blksfree(&acg, 0), blkno);
    867 			if (sblock.fs_contigsumsize > 0)
    868 				setbit(cg_clustersfree(&acg, 0), blkno);
    869 			acg.cg_cs.cs_nbfree++;
    870 			if (Oflag <= 1) {
    871 				int cn = old_cbtocylno(&sblock, d);
    872 				old_cg_blktot(&acg, 0)[cn]++;
    873 				old_cg_blks(&sblock, &acg,
    874 				    cn, 0)[old_cbtorpos(&sblock, d)]++;
    875 			}
    876 			d += sblock.fs_frag;
    877 			blkno++;
    878 		}
    879 	}
    880 	if ((i = (dupper & (sblock.fs_frag - 1))) != 0) {
    881 		acg.cg_frsum[sblock.fs_frag - i]++;
    882 		for (d = dupper + sblock.fs_frag - i; dupper < d; dupper++) {
    883 			setbit(cg_blksfree(&acg, 0), dupper);
    884 			acg.cg_cs.cs_nffree++;
    885 		}
    886 	}
    887 	for (d = dupper, blkno = dupper >> sblock.fs_fragshift;
    888 	     d + sblock.fs_frag <= acg.cg_ndblk; ) {
    889 		setblock(&sblock, cg_blksfree(&acg, 0), blkno);
    890 		if (sblock.fs_contigsumsize > 0)
    891 			setbit(cg_clustersfree(&acg, 0), blkno);
    892 		acg.cg_cs.cs_nbfree++;
    893 		if (Oflag <= 1) {
    894 			int cn = old_cbtocylno(&sblock, d);
    895 			old_cg_blktot(&acg, 0)[cn]++;
    896 			old_cg_blks(&sblock, &acg,
    897 			    cn, 0)[old_cbtorpos(&sblock, d)]++;
    898 		}
    899 		d += sblock.fs_frag;
    900 		blkno++;
    901 	}
    902 	if (d < acg.cg_ndblk) {
    903 		acg.cg_frsum[acg.cg_ndblk - d]++;
    904 		for (; d < acg.cg_ndblk; d++) {
    905 			setbit(cg_blksfree(&acg, 0), d);
    906 			acg.cg_cs.cs_nffree++;
    907 		}
    908 	}
    909 	if (sblock.fs_contigsumsize > 0) {
    910 		int32_t *sump = cg_clustersum(&acg, 0);
    911 		u_char *mapp = cg_clustersfree(&acg, 0);
    912 		int map = *mapp++;
    913 		int bit = 1;
    914 		int run = 0;
    915 
    916 		for (i = 0; i < acg.cg_nclusterblks; i++) {
    917 			if ((map & bit) != 0) {
    918 				run++;
    919 			} else if (run != 0) {
    920 				if (run > sblock.fs_contigsumsize)
    921 					run = sblock.fs_contigsumsize;
    922 				sump[run]++;
    923 				run = 0;
    924 			}
    925 			if ((i & (CHAR_BIT - 1)) != (CHAR_BIT - 1)) {
    926 				bit <<= 1;
    927 			} else {
    928 				map = *mapp++;
    929 				bit = 1;
    930 			}
    931 		}
    932 		if (run != 0) {
    933 			if (run > sblock.fs_contigsumsize)
    934 				run = sblock.fs_contigsumsize;
    935 			sump[run]++;
    936 		}
    937 	}
    938 	*fscs_next++ = acg.cg_cs;
    939 	if (fscs_next == fscs_end) {
    940 		/* write block of cylinder group summary info into cyl 0 */
    941 		if (needswap)
    942 			ffs_csum_swap(fscs_reset, fscs_reset, sblock.fs_fsize);
    943 		fs_csaddr++;
    944 		wtfs(FFS_FSBTODB(&sblock, fs_csaddr), sblock.fs_fsize, fscs_reset);
    945 		fscs_next = fscs_reset;
    946 		memset(fscs_next, 0, sblock.fs_fsize);
    947 	}
    948 	/*
    949 	 * Write out the duplicate super block, the cylinder group map
    950 	 * and two blocks worth of inodes in a single write.
    951 	 */
    952 	start = sblock.fs_bsize > SBLOCKSIZE ? sblock.fs_bsize : SBLOCKSIZE;
    953 	memcpy(&iobuf[start], &acg, sblock.fs_cgsize);
    954 	if (needswap)
    955 		ffs_cg_swap(&acg, (struct cg*)&iobuf[start], &sblock);
    956 	start += sblock.fs_bsize;
    957 	dp1 = (struct ufs1_dinode *)(&iobuf[start]);
    958 	dp2 = (struct ufs2_dinode *)(&iobuf[start]);
    959 	for (i = MIN(sblock.fs_ipg, 2) * FFS_INOPB(&sblock); i != 0; i--) {
    960 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
    961 			/* No need to swap, it'll stay random */
    962 			dp1->di_gen = arc4random() & INT32_MAX;
    963 			dp1++;
    964 		} else {
    965 			dp2->di_gen = arc4random() & INT32_MAX;
    966 			dp2++;
    967 		}
    968 	}
    969 	wtfs(FFS_FSBTODB(&sblock, cgsblock(&sblock, cylno)), iobufsize, iobuf);
    970 	/*
    971 	 * For the old file system, we have to initialize all the inodes.
    972 	 */
    973 	if (sblock.fs_magic != FS_UFS1_MAGIC)
    974 		return;
    975 
    976 	/* Write 'd' (usually 16 * fs_frag) file-system fragments at once */
    977 	d = (iobuf_memsize - start) / sblock.fs_bsize * sblock.fs_frag;
    978 	dupper = sblock.fs_ipg / FFS_INOPF(&sblock);
    979 	for (i = 2 * sblock.fs_frag; i < dupper; i += d) {
    980 		if (d > dupper - i)
    981 			d = dupper - i;
    982 		dp1 = (struct ufs1_dinode *)(&iobuf[start]);
    983 		do
    984 			dp1->di_gen = arc4random() & INT32_MAX;
    985 		while ((char *)++dp1 < &iobuf[iobuf_memsize]);
    986 		wtfs(FFS_FSBTODB(&sblock, cgimin(&sblock, cylno) + i),
    987 		    d * sblock.fs_bsize / sblock.fs_frag, &iobuf[start]);
    988 	}
    989 }
    990 
    991 /*
    992  * initialize the file system
    993  */
    994 
    995 #ifdef LOSTDIR
    996 #define	PREDEFDIR 3
    997 #else
    998 #define	PREDEFDIR 2
    999 #endif
   1000 
   1001 struct direct root_dir[] = {
   1002 	{ UFS_ROOTINO, sizeof(struct direct), DT_DIR, 1, "." },
   1003 	{ UFS_ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
   1004 #ifdef LOSTDIR
   1005 	{ LOSTFOUNDINO, sizeof(struct direct), DT_DIR, 10, "lost+found" },
   1006 #endif
   1007 };
   1008 struct odirect {
   1009 	u_int32_t d_ino;
   1010 	u_int16_t d_reclen;
   1011 	u_int16_t d_namlen;
   1012 	u_char	d_name[FFS_MAXNAMLEN + 1];
   1013 } oroot_dir[] = {
   1014 	{ UFS_ROOTINO, sizeof(struct direct), 1, "." },
   1015 	{ UFS_ROOTINO, sizeof(struct direct), 2, ".." },
   1016 #ifdef LOSTDIR
   1017 	{ LOSTFOUNDINO, sizeof(struct direct), 10, "lost+found" },
   1018 #endif
   1019 };
   1020 #ifdef LOSTDIR
   1021 struct direct lost_found_dir[] = {
   1022 	{ LOSTFOUNDINO, sizeof(struct direct), DT_DIR, 1, "." },
   1023 	{ UFS_ROOTINO, sizeof(struct direct), DT_DIR, 2, ".." },
   1024 	{ 0, DIRBLKSIZ, 0, 0, 0 },
   1025 };
   1026 struct odirect olost_found_dir[] = {
   1027 	{ LOSTFOUNDINO, sizeof(struct direct), 1, "." },
   1028 	{ UFS_ROOTINO, sizeof(struct direct), 2, ".." },
   1029 	{ 0, DIRBLKSIZ, 0, 0 },
   1030 };
   1031 #endif
   1032 
   1033 static void copy_dir(struct direct *, struct direct *);
   1034 
   1035 int
   1036 fsinit(const struct timeval *tv, mode_t mfsmode, uid_t mfsuid, gid_t mfsgid)
   1037 {
   1038 	union dinode node;
   1039 	union Buffer buf __aligned(DEV_BSIZE);
   1040 	int i;
   1041 	int qblocks = 0;
   1042 	int qinos = 0;
   1043 	uint8_t q2h_hash_shift;
   1044 	uint16_t q2h_hash_mask;
   1045 #ifdef LOSTDIR
   1046 	int dirblksiz = DIRBLKSIZ;
   1047 	if (isappleufs)
   1048 		dirblksiz = APPLEUFS_DIRBLKSIZ;
   1049 	int nextino = LOSTFOUNDINO+1;
   1050 #else
   1051 	int nextino = UFS_ROOTINO+1;
   1052 #endif
   1053 
   1054 	/*
   1055 	 * initialize the node
   1056 	 */
   1057 
   1058 #ifdef LOSTDIR
   1059 	/*
   1060 	 * create the lost+found directory
   1061 	 */
   1062 	memset(&node, 0, sizeof(node));
   1063 	if (Oflag == 0) {
   1064 		(void)makedir(&buf, (struct direct *)olost_found_dir, 2);
   1065 		for (i = dirblksiz; i < sblock.fs_bsize; i += dirblksiz)
   1066 			copy_dir((struct direct*)&olost_found_dir[2],
   1067 				(struct direct*)&buf[i]);
   1068 	} else {
   1069 		(void)makedir(&buf, lost_found_dir, 2);
   1070 		for (i = dirblksiz; i < sblock.fs_bsize; i += dirblksiz)
   1071 			copy_dir(&lost_found_dir[2], (struct direct*)&buf[i]);
   1072 	}
   1073 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
   1074 		node.dp1.di_atime = tv->tv_sec;
   1075 		node.dp1.di_atimensec = tv->tv_usec * 1000;
   1076 		node.dp1.di_mtime = tv->tv_sec;
   1077 		node.dp1.di_mtimensec = tv->tv_usec * 1000;
   1078 		node.dp1.di_ctime = tv->tv_sec;
   1079 		node.dp1.di_ctimensec = tv->tv_usec * 1000;
   1080 		node.dp1.di_mode = IFDIR | UMASK;
   1081 		node.dp1.di_nlink = 2;
   1082 		node.dp1.di_size = sblock.fs_bsize;
   1083 		node.dp1.di_db[0] = alloc(node.dp1.di_size, node.dp1.di_mode);
   1084 		if (node.dp1.di_db[0] == 0)
   1085 			return (0);
   1086 		node.dp1.di_blocks = btodb(ffs_fragroundup(&sblock,
   1087 		    node.dp1.di_size));
   1088 		qblocks += node.dp1.di_blocks;
   1089 		node.dp1.di_uid = geteuid();
   1090 		node.dp1.di_gid = getegid();
   1091 		wtfs(FFS_FSBTODB(&sblock, node.dp1.di_db[0]), node.dp1.di_size,
   1092 		    buf);
   1093 	} else {
   1094 		node.dp2.di_atime = tv->tv_sec;
   1095 		node.dp2.di_atimensec = tv->tv_usec * 1000;
   1096 		node.dp2.di_mtime = tv->tv_sec;
   1097 		node.dp2.di_mtimensec = tv->tv_usec * 1000;
   1098 		node.dp2.di_ctime = tv->tv_sec;
   1099 		node.dp2.di_ctimensec = tv->tv_usec * 1000;
   1100 		node.dp2.di_birthtime = tv->tv_sec;
   1101 		node.dp2.di_birthnsec = tv->tv_usec * 1000;
   1102 		node.dp2.di_mode = IFDIR | UMASK;
   1103 		node.dp2.di_nlink = 2;
   1104 		node.dp2.di_size = sblock.fs_bsize;
   1105 		node.dp2.di_db[0] = alloc(node.dp2.di_size, node.dp2.di_mode);
   1106 		if (node.dp2.di_db[0] == 0)
   1107 			return (0);
   1108 		node.dp2.di_blocks = btodb(ffs_fragroundup(&sblock,
   1109 		    node.dp2.di_size));
   1110 		qblocks += node.dp2.di_blocks;
   1111 		node.dp2.di_uid = geteuid();
   1112 		node.dp2.di_gid = getegid();
   1113 		wtfs(FFS_FSBTODB(&sblock, node.dp2.di_db[0]), node.dp2.di_size,
   1114 		    buf);
   1115 	}
   1116 	qinos++;
   1117 	iput(&node, LOSTFOUNDINO);
   1118 #endif
   1119 	/*
   1120 	 * create the root directory
   1121 	 */
   1122 	memset(&node, 0, sizeof(node));
   1123 	if (Oflag <= 1) {
   1124 		if (mfs) {
   1125 			node.dp1.di_mode = IFDIR | mfsmode;
   1126 			node.dp1.di_uid = mfsuid;
   1127 			node.dp1.di_gid = mfsgid;
   1128 		} else {
   1129 			node.dp1.di_mode = IFDIR | UMASK;
   1130 			node.dp1.di_uid = geteuid();
   1131 			node.dp1.di_gid = getegid();
   1132 		}
   1133 		node.dp1.di_nlink = PREDEFDIR;
   1134 		if (Oflag == 0)
   1135 			node.dp1.di_size = makedir(&buf,
   1136 			    (struct direct *)oroot_dir, PREDEFDIR);
   1137 		else
   1138 			node.dp1.di_size = makedir(&buf, root_dir, PREDEFDIR);
   1139 		node.dp1.di_db[0] = alloc(sblock.fs_fsize, node.dp1.di_mode);
   1140 		if (node.dp1.di_db[0] == 0)
   1141 			return (0);
   1142 		node.dp1.di_blocks = btodb(ffs_fragroundup(&sblock,
   1143 		    node.dp1.di_size));
   1144 		qblocks += node.dp1.di_blocks;
   1145 		wtfs(FFS_FSBTODB(&sblock, node.dp1.di_db[0]), sblock.fs_fsize, &buf);
   1146 	} else {
   1147 		if (mfs) {
   1148 			node.dp2.di_mode = IFDIR | mfsmode;
   1149 			node.dp2.di_uid = mfsuid;
   1150 			node.dp2.di_gid = mfsgid;
   1151 		} else {
   1152 			node.dp2.di_mode = IFDIR | UMASK;
   1153 			node.dp2.di_uid = geteuid();
   1154 			node.dp2.di_gid = getegid();
   1155 		}
   1156 		node.dp2.di_atime = tv->tv_sec;
   1157 		node.dp2.di_atimensec = tv->tv_usec * 1000;
   1158 		node.dp2.di_mtime = tv->tv_sec;
   1159 		node.dp2.di_mtimensec = tv->tv_usec * 1000;
   1160 		node.dp2.di_ctime = tv->tv_sec;
   1161 		node.dp2.di_ctimensec = tv->tv_usec * 1000;
   1162 		node.dp2.di_birthtime = tv->tv_sec;
   1163 		node.dp2.di_birthnsec = tv->tv_usec * 1000;
   1164 		node.dp2.di_nlink = PREDEFDIR;
   1165 		node.dp2.di_size = makedir(&buf, root_dir, PREDEFDIR);
   1166 		node.dp2.di_db[0] = alloc(sblock.fs_fsize, node.dp2.di_mode);
   1167 		if (node.dp2.di_db[0] == 0)
   1168 			return (0);
   1169 		node.dp2.di_blocks = btodb(ffs_fragroundup(&sblock,
   1170 		    node.dp2.di_size));
   1171 		qblocks += node.dp2.di_blocks;
   1172 		wtfs(FFS_FSBTODB(&sblock, node.dp2.di_db[0]), sblock.fs_fsize, &buf);
   1173 	}
   1174 	qinos++;
   1175 	iput(&node, UFS_ROOTINO);
   1176 	/*
   1177 	 * compute the size of the hash table
   1178 	 * We know the smallest block size is 4k, so we can use 2k
   1179 	 * for the hash table; as an entry is 8 bytes we can store
   1180 	 * 256 entries. So let start q2h_hash_shift at 8
   1181 	 */
   1182 	for (q2h_hash_shift = 8;
   1183 	    q2h_hash_shift < 15;
   1184 	    q2h_hash_shift++) {
   1185 		if ((sizeof(uint64_t) << (q2h_hash_shift + 1)) +
   1186 		    sizeof(struct quota2_header) > (u_int)sblock.fs_bsize)
   1187 			break;
   1188 	}
   1189 	q2h_hash_mask = (1 << q2h_hash_shift) - 1;
   1190 	for (i = 0; i < MAXQUOTAS; i++) {
   1191 		struct quota2_header *q2h;
   1192 		struct quota2_entry *q2e;
   1193 		uint64_t offset;
   1194 		uid_t uid = (i == USRQUOTA ? geteuid() : getegid());
   1195 
   1196 		if ((quotas & FS_Q2_DO_TYPE(i)) == 0)
   1197 			continue;
   1198 		quota2_create_blk0(sblock.fs_bsize, &buf, q2h_hash_shift,
   1199 		    i, needswap);
   1200 		/* grab an entry from header for root dir */
   1201 		q2h = &buf.q2h;
   1202 		offset = ufs_rw64(q2h->q2h_free, needswap);
   1203 		q2e = (void *)((char *)&buf + offset);
   1204 		q2h->q2h_free = q2e->q2e_next;
   1205 		memcpy(q2e, &q2h->q2h_defentry, sizeof(*q2e));
   1206 		q2e->q2e_uid = ufs_rw32(uid, needswap);
   1207 		q2e->q2e_val[QL_BLOCK].q2v_cur = ufs_rw64(qblocks, needswap);
   1208 		q2e->q2e_val[QL_FILE].q2v_cur = ufs_rw64(qinos, needswap);
   1209 		/* add to the hash entry */
   1210 		q2e->q2e_next = q2h->q2h_entries[uid & q2h_hash_mask];
   1211 		q2h->q2h_entries[uid & q2h_hash_mask] =
   1212 		    ufs_rw64(offset, needswap);
   1213 
   1214 		memset(&node, 0, sizeof(node));
   1215 		if (sblock.fs_magic == FS_UFS1_MAGIC) {
   1216 			node.dp1.di_atime = tv->tv_sec;
   1217 			node.dp1.di_atimensec = tv->tv_usec * 1000;
   1218 			node.dp1.di_mtime = tv->tv_sec;
   1219 			node.dp1.di_mtimensec = tv->tv_usec * 1000;
   1220 			node.dp1.di_ctime = tv->tv_sec;
   1221 			node.dp1.di_ctimensec = tv->tv_usec * 1000;
   1222 			node.dp1.di_mode = IFREG;
   1223 			node.dp1.di_nlink = 1;
   1224 			node.dp1.di_size = sblock.fs_bsize;
   1225 			node.dp1.di_db[0] =
   1226 			    alloc(node.dp1.di_size, node.dp1.di_mode);
   1227 			if (node.dp1.di_db[0] == 0)
   1228 				return (0);
   1229 			node.dp1.di_blocks = btodb(ffs_fragroundup(&sblock,
   1230 			    node.dp1.di_size));
   1231 			node.dp1.di_uid = geteuid();
   1232 			node.dp1.di_gid = getegid();
   1233 			wtfs(FFS_FSBTODB(&sblock, node.dp1.di_db[0]),
   1234 			     node.dp1.di_size, &buf);
   1235 		} else {
   1236 			node.dp2.di_atime = tv->tv_sec;
   1237 			node.dp2.di_atimensec = tv->tv_usec * 1000;
   1238 			node.dp2.di_mtime = tv->tv_sec;
   1239 			node.dp2.di_mtimensec = tv->tv_usec * 1000;
   1240 			node.dp2.di_ctime = tv->tv_sec;
   1241 			node.dp2.di_ctimensec = tv->tv_usec * 1000;
   1242 			node.dp2.di_birthtime = tv->tv_sec;
   1243 			node.dp2.di_birthnsec = tv->tv_usec * 1000;
   1244 			node.dp2.di_mode = IFREG;
   1245 			node.dp2.di_nlink = 1;
   1246 			node.dp2.di_size = sblock.fs_bsize;
   1247 			node.dp2.di_db[0] =
   1248 			    alloc(node.dp2.di_size, node.dp2.di_mode);
   1249 			if (node.dp2.di_db[0] == 0)
   1250 				return (0);
   1251 			node.dp2.di_blocks = btodb(ffs_fragroundup(&sblock,
   1252 			    node.dp2.di_size));
   1253 			node.dp2.di_uid = geteuid();
   1254 			node.dp2.di_gid = getegid();
   1255 			wtfs(FFS_FSBTODB(&sblock, node.dp2.di_db[0]),
   1256 			    node.dp2.di_size, &buf);
   1257 		}
   1258 		iput(&node, nextino);
   1259 		sblock.fs_quotafile[i] = nextino;
   1260 		nextino++;
   1261 	}
   1262 	return (1);
   1263 }
   1264 
   1265 /*
   1266  * construct a set of directory entries in "buf".
   1267  * return size of directory.
   1268  */
   1269 int
   1270 makedir(union Buffer *buf, struct direct *protodir, int entries)
   1271 {
   1272 	char *cp;
   1273 	int i, spcleft;
   1274 	int dirblksiz = UFS_DIRBLKSIZ;
   1275 	if (isappleufs)
   1276 		dirblksiz = APPLEUFS_DIRBLKSIZ;
   1277 
   1278 	memset(buf, 0, dirblksiz);
   1279 	spcleft = dirblksiz;
   1280 	for (cp = buf->data, i = 0; i < entries - 1; i++) {
   1281 		protodir[i].d_reclen = UFS_DIRSIZ(Oflag == 0, &protodir[i], 0);
   1282 		copy_dir(&protodir[i], (struct direct*)cp);
   1283 		cp += protodir[i].d_reclen;
   1284 		spcleft -= protodir[i].d_reclen;
   1285 	}
   1286 	protodir[i].d_reclen = spcleft;
   1287 	copy_dir(&protodir[i], (struct direct*)cp);
   1288 	return (dirblksiz);
   1289 }
   1290 
   1291 /*
   1292  * allocate a block or frag
   1293  */
   1294 daddr_t
   1295 alloc(int size, int mode)
   1296 {
   1297 	int i, frag;
   1298 	daddr_t d, blkno;
   1299 
   1300 	rdfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
   1301 	/* fs -> host byte order */
   1302 	if (needswap)
   1303 		ffs_cg_swap(&acg, &acg, &sblock);
   1304 	if (acg.cg_magic != CG_MAGIC) {
   1305 		printf("cg 0: bad magic number\n");
   1306 		return (0);
   1307 	}
   1308 	if (acg.cg_cs.cs_nbfree == 0) {
   1309 		printf("first cylinder group ran out of space\n");
   1310 		return (0);
   1311 	}
   1312 	for (d = 0; d < acg.cg_ndblk; d += sblock.fs_frag)
   1313 		if (isblock(&sblock, cg_blksfree(&acg, 0),
   1314 		    d >> sblock.fs_fragshift))
   1315 			goto goth;
   1316 	printf("internal error: can't find block in cyl 0\n");
   1317 	return (0);
   1318 goth:
   1319 	blkno = ffs_fragstoblks(&sblock, d);
   1320 	clrblock(&sblock, cg_blksfree(&acg, 0), blkno);
   1321 	if (sblock.fs_contigsumsize > 0)
   1322 		clrbit(cg_clustersfree(&acg, 0), blkno);
   1323 	acg.cg_cs.cs_nbfree--;
   1324 	sblock.fs_cstotal.cs_nbfree--;
   1325 	fscs_0->cs_nbfree--;
   1326 	if (mode & IFDIR) {
   1327 		acg.cg_cs.cs_ndir++;
   1328 		sblock.fs_cstotal.cs_ndir++;
   1329 		fscs_0->cs_ndir++;
   1330 	}
   1331 	if (Oflag <= 1) {
   1332 		int cn = old_cbtocylno(&sblock, d);
   1333 		old_cg_blktot(&acg, 0)[cn]--;
   1334 		old_cg_blks(&sblock, &acg,
   1335 		    cn, 0)[old_cbtorpos(&sblock, d)]--;
   1336 	}
   1337 	if (size != sblock.fs_bsize) {
   1338 		frag = howmany(size, sblock.fs_fsize);
   1339 		fscs_0->cs_nffree += sblock.fs_frag - frag;
   1340 		sblock.fs_cstotal.cs_nffree += sblock.fs_frag - frag;
   1341 		acg.cg_cs.cs_nffree += sblock.fs_frag - frag;
   1342 		acg.cg_frsum[sblock.fs_frag - frag]++;
   1343 		for (i = frag; i < sblock.fs_frag; i++)
   1344 			setbit(cg_blksfree(&acg, 0), d + i);
   1345 	}
   1346 	/* host -> fs byte order */
   1347 	if (needswap)
   1348 		ffs_cg_swap(&acg, &acg, &sblock);
   1349 	wtfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
   1350 	return (d);
   1351 }
   1352 
   1353 /*
   1354  * Allocate an inode on the disk
   1355  */
   1356 static void
   1357 iput(union dinode *ip, ino_t ino)
   1358 {
   1359 	daddr_t d;
   1360 	int i;
   1361 	struct ufs1_dinode *dp1;
   1362 	struct ufs2_dinode *dp2;
   1363 
   1364 	rdfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
   1365 	/* fs -> host byte order */
   1366 	if (needswap)
   1367 		ffs_cg_swap(&acg, &acg, &sblock);
   1368 	if (acg.cg_magic != CG_MAGIC) {
   1369 		printf("cg 0: bad magic number\n");
   1370 		fserr(31);
   1371 	}
   1372 	acg.cg_cs.cs_nifree--;
   1373 	setbit(cg_inosused(&acg, 0), ino);
   1374 	/* host -> fs byte order */
   1375 	if (needswap)
   1376 		ffs_cg_swap(&acg, &acg, &sblock);
   1377 	wtfs(FFS_FSBTODB(&sblock, cgtod(&sblock, 0)), sblock.fs_cgsize, &acg);
   1378 	sblock.fs_cstotal.cs_nifree--;
   1379 	fscs_0->cs_nifree--;
   1380 	if (ino >= (ino_t)(sblock.fs_ipg * sblock.fs_ncg)) {
   1381 		printf("fsinit: inode value out of range (%llu).\n",
   1382 		    (unsigned long long)ino);
   1383 		fserr(32);
   1384 	}
   1385 	d = FFS_FSBTODB(&sblock, ino_to_fsba(&sblock, ino));
   1386 	rdfs(d, sblock.fs_bsize, (char *)iobuf);
   1387 	if (sblock.fs_magic == FS_UFS1_MAGIC) {
   1388 		dp1 = (struct ufs1_dinode *)iobuf;
   1389 		dp1 += ino_to_fsbo(&sblock, ino);
   1390 		if (needswap) {
   1391 			ffs_dinode1_swap(&ip->dp1, dp1);
   1392 			/* ffs_dinode1_swap() doesn't swap blocks addrs */
   1393 			for (i=0; i<UFS_NDADDR; i++)
   1394 			    dp1->di_db[i] = bswap32(ip->dp1.di_db[i]);
   1395 			for (i=0; i<UFS_NIADDR; i++)
   1396 			    dp1->di_ib[i] = bswap32(ip->dp1.di_ib[i]);
   1397 		} else
   1398 			*dp1 = ip->dp1;
   1399 		dp1->di_gen = arc4random() & INT32_MAX;
   1400 	} else {
   1401 		dp2 = (struct ufs2_dinode *)iobuf;
   1402 		dp2 += ino_to_fsbo(&sblock, ino);
   1403 		if (needswap) {
   1404 			ffs_dinode2_swap(&ip->dp2, dp2);
   1405 			for (i=0; i<UFS_NDADDR; i++)
   1406 			    dp2->di_db[i] = bswap64(ip->dp2.di_db[i]);
   1407 			for (i=0; i<UFS_NIADDR; i++)
   1408 			    dp2->di_ib[i] = bswap64(ip->dp2.di_ib[i]);
   1409 		} else
   1410 			*dp2 = ip->dp2;
   1411 		dp2->di_gen = arc4random() & INT32_MAX;
   1412 	}
   1413 	wtfs(d, sblock.fs_bsize, iobuf);
   1414 }
   1415 
   1416 /*
   1417  * read a block from the file system
   1418  */
   1419 void
   1420 rdfs(daddr_t bno, int size, void *bf)
   1421 {
   1422 	int n;
   1423 	off_t offset;
   1424 
   1425 #ifdef MFS
   1426 	if (mfs) {
   1427 		if (Nflag)
   1428 			memset(bf, 0, size);
   1429 		else
   1430 			memmove(bf, membase + bno * sectorsize, size);
   1431 		return;
   1432 	}
   1433 #endif
   1434 	offset = bno;
   1435 	n = pread(fsi, bf, size, offset * sectorsize);
   1436 	if (n != size) {
   1437 		printf("rdfs: read error for sector %lld: %s\n",
   1438 		    (long long)bno, strerror(errno));
   1439 		exit(34);
   1440 	}
   1441 }
   1442 
   1443 /*
   1444  * write a block to the file system
   1445  */
   1446 void
   1447 wtfs(daddr_t bno, int size, void *bf)
   1448 {
   1449 	int n;
   1450 	off_t offset;
   1451 
   1452 	if (Nflag)
   1453 		return;
   1454 #ifdef MFS
   1455 	if (mfs) {
   1456 		memmove(membase + bno * sectorsize, bf, size);
   1457 		return;
   1458 	}
   1459 #endif
   1460 	offset = bno;
   1461 	n = pwrite(fso, bf, size, offset * sectorsize);
   1462 	if (n != size) {
   1463 		printf("wtfs: write error for sector %lld: %s\n",
   1464 		    (long long)bno, strerror(errno));
   1465 		exit(36);
   1466 	}
   1467 }
   1468 
   1469 /*
   1470  * check if a block is available
   1471  */
   1472 int
   1473 isblock(struct fs *fs, unsigned char *cp, int h)
   1474 {
   1475 	unsigned char mask;
   1476 
   1477 	switch (fs->fs_fragshift) {
   1478 	case 3:
   1479 		return (cp[h] == 0xff);
   1480 	case 2:
   1481 		mask = 0x0f << ((h & 0x1) << 2);
   1482 		return ((cp[h >> 1] & mask) == mask);
   1483 	case 1:
   1484 		mask = 0x03 << ((h & 0x3) << 1);
   1485 		return ((cp[h >> 2] & mask) == mask);
   1486 	case 0:
   1487 		mask = 0x01 << (h & 0x7);
   1488 		return ((cp[h >> 3] & mask) == mask);
   1489 	default:
   1490 #ifdef STANDALONE
   1491 		printf("isblock bad fs_fragshift %d\n", fs->fs_fragshift);
   1492 #else
   1493 		fprintf(stderr, "isblock bad fs_fragshift %d\n",
   1494 		    fs->fs_fragshift);
   1495 #endif
   1496 		return (0);
   1497 	}
   1498 }
   1499 
   1500 /*
   1501  * take a block out of the map
   1502  */
   1503 void
   1504 clrblock(struct fs *fs, unsigned char *cp, int h)
   1505 {
   1506 	switch ((fs)->fs_fragshift) {
   1507 	case 3:
   1508 		cp[h] = 0;
   1509 		return;
   1510 	case 2:
   1511 		cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2));
   1512 		return;
   1513 	case 1:
   1514 		cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1));
   1515 		return;
   1516 	case 0:
   1517 		cp[h >> 3] &= ~(0x01 << (h & 0x7));
   1518 		return;
   1519 	default:
   1520 #ifdef STANDALONE
   1521 		printf("clrblock bad fs_fragshift %d\n", fs->fs_fragshift);
   1522 #else
   1523 		fprintf(stderr, "clrblock bad fs_fragshift %d\n",
   1524 		    fs->fs_fragshift);
   1525 #endif
   1526 		return;
   1527 	}
   1528 }
   1529 
   1530 /*
   1531  * put a block into the map
   1532  */
   1533 void
   1534 setblock(struct fs *fs, unsigned char *cp, int h)
   1535 {
   1536 	switch (fs->fs_fragshift) {
   1537 	case 3:
   1538 		cp[h] = 0xff;
   1539 		return;
   1540 	case 2:
   1541 		cp[h >> 1] |= (0x0f << ((h & 0x1) << 2));
   1542 		return;
   1543 	case 1:
   1544 		cp[h >> 2] |= (0x03 << ((h & 0x3) << 1));
   1545 		return;
   1546 	case 0:
   1547 		cp[h >> 3] |= (0x01 << (h & 0x7));
   1548 		return;
   1549 	default:
   1550 #ifdef STANDALONE
   1551 		printf("setblock bad fs_frag %d\n", fs->fs_fragshift);
   1552 #else
   1553 		fprintf(stderr, "setblock bad fs_fragshift %d\n",
   1554 		    fs->fs_fragshift);
   1555 #endif
   1556 		return;
   1557 	}
   1558 }
   1559 
   1560 /* copy a direntry to a buffer, in fs byte order */
   1561 static void
   1562 copy_dir(struct direct *dir, struct direct *dbuf)
   1563 {
   1564 	memcpy(dbuf, dir, UFS_DIRSIZ(Oflag == 0, dir, 0));
   1565 	if (needswap) {
   1566 		dbuf->d_ino = bswap32(dir->d_ino);
   1567 		dbuf->d_reclen = bswap16(dir->d_reclen);
   1568 		if (Oflag == 0)
   1569 			((struct odirect*)dbuf)->d_namlen =
   1570 				bswap16(((struct odirect*)dir)->d_namlen);
   1571 	}
   1572 }
   1573 
   1574 static int
   1575 ilog2(int val)
   1576 {
   1577 	u_int n;
   1578 
   1579 	for (n = 0; n < sizeof(n) * CHAR_BIT; n++)
   1580 		if (1 << n == val)
   1581 			return (n);
   1582 	errx(1, "ilog2: %d is not a power of 2", val);
   1583 }
   1584 
   1585 static void
   1586 zap_old_sblock(int sblkoff)
   1587 {
   1588 	static int cg0_data;
   1589 	uint32_t oldfs[SBLOCKSIZE / 4] __aligned(DEV_BSIZE);
   1590 	static const struct fsm {
   1591 		uint32_t	offset;
   1592 		uint32_t	magic;
   1593 		uint32_t	mask;
   1594 	} fs_magics[] = {
   1595 		{offsetof(struct fs, fs_magic)/4, FS_UFS1_MAGIC, ~0u},
   1596 		{offsetof(struct fs, fs_magic)/4, FS_UFS2_MAGIC, ~0u},
   1597 		{0, 0x70162, ~0u},		/* LFS_MAGIC */
   1598 		{14, 0xef53, 0xffff},		/* EXT2FS (little) */
   1599 		{14, 0xef530000, 0xffff0000},	/* EXT2FS (big) */
   1600 		{.offset = ~0u},
   1601 	};
   1602 	const struct fsm *fsm;
   1603 
   1604 	if (Nflag)
   1605 		return;
   1606 
   1607 	if (sblkoff == 0)	/* Why did UFS2 add support for this?  sigh. */
   1608 		return;
   1609 
   1610 	if (cg0_data == 0)
   1611 		/* For FFSv1 this could include all the inodes. */
   1612 		cg0_data = cgsblock(&sblock, 0) * sblock.fs_fsize + iobufsize;
   1613 
   1614 	/* Ignore anything that is beyond our filesystem */
   1615 	if ((sblkoff + SBLOCKSIZE)/sectorsize >= fssize)
   1616 		return;
   1617 	/* Zero anything inside our filesystem... */
   1618 	if (sblkoff >= sblock.fs_sblockloc) {
   1619 		/* ...unless we will write that area anyway */
   1620 		if (sblkoff >= cg0_data)
   1621 			wtfs(sblkoff / sectorsize,
   1622 			    roundup(sizeof sblock, sectorsize), iobuf);
   1623 		return;
   1624 	}
   1625 
   1626 	/* The sector might contain boot code, so we must validate it */
   1627 	rdfs(sblkoff/sectorsize, sizeof oldfs, &oldfs);
   1628 	for (fsm = fs_magics; ; fsm++) {
   1629 		uint32_t v;
   1630 		if (fsm->mask == 0)
   1631 			return;
   1632 		v = oldfs[fsm->offset];
   1633 		if ((v & fsm->mask) == fsm->magic ||
   1634 		    (bswap32(v) & fsm->mask) == fsm->magic)
   1635 			break;
   1636 	}
   1637 
   1638 	/* Just zap the magic number */
   1639 	oldfs[fsm->offset] = 0;
   1640 	wtfs(sblkoff/sectorsize, sizeof oldfs, &oldfs);
   1641 }
   1642 
   1643 
   1644 #ifdef MFS
   1645 /*
   1646  * Internal version of malloc that trims the requested size if not enough
   1647  * memory is available.
   1648  */
   1649 static void *
   1650 mkfs_malloc(size_t size)
   1651 {
   1652 	u_long pgsz;
   1653 	caddr_t *memory, *extra;
   1654 	size_t exsize = 128 * 1024;
   1655 
   1656 	if (size == 0)
   1657 		return (NULL);
   1658 
   1659 	pgsz = getpagesize() - 1;
   1660 	size = (size + pgsz) &~ pgsz;
   1661 
   1662 	/* try to map requested size */
   1663 	memory = mmap(0, size, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
   1664 	    -1, 0);
   1665 	if (memory == MAP_FAILED)
   1666 		return NULL;
   1667 
   1668 	/* try to map something extra */
   1669 	extra = mmap(0, exsize, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
   1670 	    -1, 0);
   1671 	if (extra != MAP_FAILED)
   1672 		munmap(extra, exsize);
   1673 
   1674 	/* if extra memory couldn't be mapped, reduce original request accordingly */
   1675 	if (extra == MAP_FAILED) {
   1676 		munmap(memory, size);
   1677 		size -= exsize;
   1678 		memory = mmap(0, size, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE,
   1679 		    -1, 0);
   1680 		if (memory == MAP_FAILED)
   1681 			return NULL;
   1682 	}
   1683 
   1684 	return memory;
   1685 }
   1686 #endif	/* MFS */
   1687