sbin/fsck_ffs/pass5.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-3-Clause
   3  *
   4  * Copyright (c) 1980, 1986, 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 #if 0
  33 #ifndef lint
  34 static const char sccsid[] = "@(#)pass5.c       8.9 (Berkeley) 4/28/95";
  35 #endif /* not lint */
  36 #endif
  37 #include <sys/cdefs.h>
  38 __FBSDID("$FreeBSD$");
  39
  40 #include <sys/param.h>
  41 #include <sys/sysctl.h>
  42
  43 #include <ufs/ufs/dinode.h>
  44 #include <ufs/ffs/fs.h>
  45
  46 #include <err.h>
  47 #include <inttypes.h>
  48 #include <limits.h>
  49 #include <string.h>
  50 #include <libufs.h>
  51
  52 #include "fsck.h"
  53
  54 static void check_maps(u_char *, u_char *, int, ufs2_daddr_t, const char *,
  55                         int *, int, int, int);
  56 static void clear_blocks(ufs2_daddr_t start, ufs2_daddr_t end);
  57
  58 void
  59 pass5(void)
  60 {
  61         int c, i, j, blk, frags, basesize, mapsize;
  62         int inomapsize, blkmapsize;
  63         struct fs *fs = &sblock;
  64         ufs2_daddr_t d, dbase, dmax, start;
  65         int rewritecg = 0;
  66         struct csum *cs;
  67         struct csum_total cstotal;
  68         struct inodesc idesc[3];
  69         char buf[MAXBSIZE];
  70         struct cg *cg, *newcg = (struct cg *)buf;
  71         struct bufarea *cgbp;
  72
  73         inoinfo(UFS_WINO)->ino_state = USTATE;
  74         memset(newcg, 0, (size_t)fs->fs_cgsize);
  75         newcg->cg_niblk = fs->fs_ipg;
  76         /* check to see if we are to add a cylinder group check hash */
  77         if ((ckhashadd & CK_CYLGRP) != 0)
  78                 rewritecg = 1;
  79         if (cvtlevel >= 3) {
  80                 if (fs->fs_maxcontig < 2 && fs->fs_contigsumsize > 0) {
  81                         if (preen)
  82                                 pwarn("DELETING CLUSTERING MAPS\n");
  83                         if (preen || reply("DELETE CLUSTERING MAPS")) {
  84                                 fs->fs_contigsumsize = 0;
  85                                 rewritecg = 1;
  86                                 sbdirty();
  87                         }
  88                 }
  89                 if (fs->fs_maxcontig > 1) {
  90                         const char *doit = NULL;
  91
  92                         if (fs->fs_contigsumsize < 1) {
  93                                 doit = "CREAT";
  94                         } else if (fs->fs_contigsumsize < fs->fs_maxcontig &&
  95                                    fs->fs_contigsumsize < FS_MAXCONTIG) {
  96                                 doit = "EXPAND";
  97                         }
  98                         if (doit) {
  99                                 i = fs->fs_contigsumsize;
 100                                 fs->fs_contigsumsize =
 101                                     MIN(fs->fs_maxcontig, FS_MAXCONTIG);
 102                                 if (CGSIZE(fs) > (u_int)fs->fs_bsize) {
 103                                         pwarn("CANNOT %s CLUSTER MAPS\n", doit);
 104                                         fs->fs_contigsumsize = i;
 105                                 } else if (preen ||
 106                                     reply("CREATE CLUSTER MAPS")) {
 107                                         if (preen)
 108                                                 pwarn("%sING CLUSTER MAPS\n",
 109                                                     doit);
 110                                         fs->fs_cgsize =
 111                                             fragroundup(fs, CGSIZE(fs));
 112                                         rewritecg = 1;
 113                                         sbdirty();
 114                                 }
 115                         }
 116                 }
 117         }
 118         basesize = &newcg->cg_space[0] - (u_char *)(&newcg->cg_firstfield);
 119         if (sblock.fs_magic == FS_UFS2_MAGIC) {
 120                 newcg->cg_iusedoff = basesize;
 121         } else {
 122                 /*
 123                  * We reserve the space for the old rotation summary
 124                  * tables for the benefit of old kernels, but do not
 125                  * maintain them in modern kernels. In time, they can
 126                  * go away.
 127                  */
 128                 newcg->cg_old_btotoff = basesize;
 129                 newcg->cg_old_boff = newcg->cg_old_btotoff +
 130                     fs->fs_old_cpg * sizeof(int32_t);
 131                 newcg->cg_iusedoff = newcg->cg_old_boff +
 132                     fs->fs_old_cpg * fs->fs_old_nrpos * sizeof(u_int16_t);
 133                 memset(&newcg->cg_space[0], 0, newcg->cg_iusedoff - basesize);
 134         }
 135         inomapsize = howmany(fs->fs_ipg, CHAR_BIT);
 136         newcg->cg_freeoff = newcg->cg_iusedoff + inomapsize;
 137         blkmapsize = howmany(fs->fs_fpg, CHAR_BIT);
 138         newcg->cg_nextfreeoff = newcg->cg_freeoff + blkmapsize;
 139         if (fs->fs_contigsumsize > 0) {
 140                 newcg->cg_clustersumoff = newcg->cg_nextfreeoff -
 141                     sizeof(u_int32_t);
 142                 newcg->cg_clustersumoff =
 143                     roundup(newcg->cg_clustersumoff, sizeof(u_int32_t));
 144                 newcg->cg_clusteroff = newcg->cg_clustersumoff +
 145                     (fs->fs_contigsumsize + 1) * sizeof(u_int32_t);
 146                 newcg->cg_nextfreeoff = newcg->cg_clusteroff +
 147                     howmany(fragstoblks(fs, fs->fs_fpg), CHAR_BIT);
 148         }
 149         newcg->cg_magic = CG_MAGIC;
 150         mapsize = newcg->cg_nextfreeoff - newcg->cg_iusedoff;
 151         memset(&idesc[0], 0, sizeof idesc);
 152         for (i = 0; i < 3; i++)
 153                 idesc[i].id_type = ADDR;
 154         memset(&cstotal, 0, sizeof(struct csum_total));
 155         dmax = blknum(fs, fs->fs_size + fs->fs_frag - 1);
 156         for (d = fs->fs_size; d < dmax; d++)
 157                 setbmap(d);
 158         for (c = 0; c < fs->fs_ncg; c++) {
 159                 if (got_siginfo) {
 160                         printf("%s: phase 5: cyl group %d of %d (%d%%)\n",
 161                             cdevname, c, sblock.fs_ncg,
 162                             c * 100 / sblock.fs_ncg);
 163                         got_siginfo = 0;
 164                 }
 165                 if (got_sigalarm) {
 166                         setproctitle("%s p5 %d%%", cdevname,
 167                             c * 100 / sblock.fs_ncg);
 168                         got_sigalarm = 0;
 169                 }
 170                 cgbp = cglookup(c);
 171                 cg = cgbp->b_un.b_cg;
 172                 if (!cg_chkmagic(cg))
 173                         pfatal("CG %d: BAD MAGIC NUMBER\n", c);
 174                 /*
 175                  * If we have a cylinder group check hash and are not adding
 176                  * it for the first time, verify that it is good.
 177                  */
 178                 if ((fs->fs_metackhash & CK_CYLGRP) != 0 &&
 179                     (ckhashadd & CK_CYLGRP) == 0) {
 180                         uint32_t ckhash, thishash;
 181
 182                         ckhash = cg->cg_ckhash;
 183                         cg->cg_ckhash = 0;
 184                         thishash = calculate_crc32c(~0L, cg, fs->fs_cgsize);
 185                         if (ckhash == thishash) {
 186                                 cg->cg_ckhash = ckhash;
 187                         } else {
 188                                 pwarn("CG %d: BAD CHECK-HASH %#x vs %#x\n",
 189                                     c, ckhash, thishash);
 190                                 cg->cg_ckhash = thishash;
 191                                 cgdirty(cgbp);
 192                         }
 193                 }
 194                 newcg->cg_time = cg->cg_time;
 195                 newcg->cg_old_time = cg->cg_old_time;
 196                 newcg->cg_unrefs = cg->cg_unrefs;
 197                 newcg->cg_ckhash = cg->cg_ckhash;
 198                 newcg->cg_cgx = c;
 199                 dbase = cgbase(fs, c);
 200                 dmax = dbase + fs->fs_fpg;
 201                 if (dmax > fs->fs_size)
 202                         dmax = fs->fs_size;
 203                 newcg->cg_ndblk = dmax - dbase;
 204                 if (fs->fs_magic == FS_UFS1_MAGIC) {
 205                         if (c == fs->fs_ncg - 1)
 206                                 newcg->cg_old_ncyl = howmany(newcg->cg_ndblk,
 207                                     fs->fs_fpg / fs->fs_old_cpg);
 208                         else
 209                                 newcg->cg_old_ncyl = fs->fs_old_cpg;
 210                         newcg->cg_old_niblk = fs->fs_ipg;
 211                         newcg->cg_niblk = 0;
 212                 }
 213                 if (fs->fs_contigsumsize > 0)
 214                         newcg->cg_nclusterblks = newcg->cg_ndblk / fs->fs_frag;
 215                 newcg->cg_cs.cs_ndir = 0;
 216                 newcg->cg_cs.cs_nffree = 0;
 217                 newcg->cg_cs.cs_nbfree = 0;
 218                 newcg->cg_cs.cs_nifree = fs->fs_ipg;
 219                 if (cg->cg_rotor >= 0 && cg->cg_rotor < newcg->cg_ndblk)
 220                         newcg->cg_rotor = cg->cg_rotor;
 221                 else
 222                         newcg->cg_rotor = 0;
 223                 if (cg->cg_frotor >= 0 && cg->cg_frotor < newcg->cg_ndblk)
 224                         newcg->cg_frotor = cg->cg_frotor;
 225                 else
 226                         newcg->cg_frotor = 0;
 227                 if (cg->cg_irotor >= 0 && cg->cg_irotor < fs->fs_ipg)
 228                         newcg->cg_irotor = cg->cg_irotor;
 229                 else
 230                         newcg->cg_irotor = 0;
 231                 if (fs->fs_magic == FS_UFS1_MAGIC) {
 232                         newcg->cg_initediblk = 0;
 233                 } else {
 234                         if ((unsigned)cg->cg_initediblk > fs->fs_ipg)
 235                                 newcg->cg_initediblk = fs->fs_ipg;
 236                         else
 237                                 newcg->cg_initediblk = cg->cg_initediblk;
 238                 }
 239                 memset(&newcg->cg_frsum[0], 0, sizeof newcg->cg_frsum);
 240                 memset(cg_inosused(newcg), 0, (size_t)(mapsize));
 241                 j = fs->fs_ipg * c;
 242                 for (i = 0; i < inostathead[c].il_numalloced; j++, i++) {
 243                         switch (inoinfo(j)->ino_state) {
 244
 245                         case USTATE:
 246                                 break;
 247
 248                         case DSTATE:
 249                         case DCLEAR:
 250                         case DFOUND:
 251                         case DZLINK:
 252                                 newcg->cg_cs.cs_ndir++;
 253                                 /* FALLTHROUGH */
 254
 255                         case FSTATE:
 256                         case FCLEAR:
 257                         case FZLINK:
 258                                 newcg->cg_cs.cs_nifree--;
 259                                 setbit(cg_inosused(newcg), i);
 260                                 break;
 261
 262                         default:
 263                                 if (j < (int)UFS_ROOTINO)
 264                                         break;
 265                                 errx(EEXIT, "BAD STATE %d FOR INODE I=%d",
 266                                     inoinfo(j)->ino_state, j);
 267                         }
 268                 }
 269                 if (c == 0)
 270                         for (i = 0; i < (int)UFS_ROOTINO; i++) {
 271                                 setbit(cg_inosused(newcg), i);
 272                                 newcg->cg_cs.cs_nifree--;
 273                         }
 274                 start = -1;
 275                 for (i = 0, d = dbase;
 276                      d < dmax;
 277                      d += fs->fs_frag, i += fs->fs_frag) {
 278                         frags = 0;
 279                         for (j = 0; j < fs->fs_frag; j++) {
 280                                 if (testbmap(d + j)) {
 281                                         if ((Eflag || Zflag) && start != -1) {
 282                                                 clear_blocks(start, d + j - 1);
 283                                                 start = -1;
 284                                         }
 285                                         continue;
 286                                 }
 287                                 if (start == -1)
 288                                         start = d + j;
 289                                 setbit(cg_blksfree(newcg), i + j);
 290                                 frags++;
 291                         }
 292                         if (frags == fs->fs_frag) {
 293                                 newcg->cg_cs.cs_nbfree++;
 294                                 if (fs->fs_contigsumsize > 0)
 295                                         setbit(cg_clustersfree(newcg),
 296                                             i / fs->fs_frag);
 297                         } else if (frags > 0) {
 298                                 newcg->cg_cs.cs_nffree += frags;
 299                                 blk = blkmap(fs, cg_blksfree(newcg), i);
 300                                 ffs_fragacct(fs, blk, newcg->cg_frsum, 1);
 301                         }
 302                 }
 303                 if ((Eflag || Zflag) && start != -1)
 304                         clear_blocks(start, d - 1);
 305                 if (fs->fs_contigsumsize > 0) {
 306                         int32_t *sump = cg_clustersum(newcg);
 307                         u_char *mapp = cg_clustersfree(newcg);
 308                         int map = *mapp++;
 309                         int bit = 1;
 310                         int run = 0;
 311
 312                         for (i = 0; i < newcg->cg_nclusterblks; i++) {
 313                                 if ((map & bit) != 0) {
 314                                         run++;
 315                                 } else if (run != 0) {
 316                                         if (run > fs->fs_contigsumsize)
 317                                                 run = fs->fs_contigsumsize;
 318                                         sump[run]++;
 319                                         run = 0;
 320                                 }
 321                                 if ((i & (CHAR_BIT - 1)) != (CHAR_BIT - 1)) {
 322                                         bit <<= 1;
 323                                 } else {
 324                                         map = *mapp++;
 325                                         bit = 1;
 326                                 }
 327                         }
 328                         if (run != 0) {
 329                                 if (run > fs->fs_contigsumsize)
 330                                         run = fs->fs_contigsumsize;
 331                                 sump[run]++;
 332                         }
 333                 }
 334
 335                 if (bkgrdflag != 0) {
 336                         cstotal.cs_nffree += cg->cg_cs.cs_nffree;
 337                         cstotal.cs_nbfree += cg->cg_cs.cs_nbfree;
 338                         cstotal.cs_nifree += cg->cg_cs.cs_nifree;
 339                         cstotal.cs_ndir += cg->cg_cs.cs_ndir;
 340                 } else {
 341                         cstotal.cs_nffree += newcg->cg_cs.cs_nffree;
 342                         cstotal.cs_nbfree += newcg->cg_cs.cs_nbfree;
 343                         cstotal.cs_nifree += newcg->cg_cs.cs_nifree;
 344                         cstotal.cs_ndir += newcg->cg_cs.cs_ndir;
 345                 }
 346                 cs = &fs->fs_cs(fs, c);
 347                 if (cursnapshot == 0 &&
 348                     memcmp(&newcg->cg_cs, cs, sizeof *cs) != 0 &&
 349                     dofix(&idesc[0], "FREE BLK COUNT(S) WRONG IN SUPERBLK")) {
 350                         memmove(cs, &newcg->cg_cs, sizeof *cs);
 351                         sbdirty();
 352                 }
 353                 if (rewritecg) {
 354                         memmove(cg, newcg, (size_t)fs->fs_cgsize);
 355                         cgdirty(cgbp);
 356                         continue;
 357                 }
 358                 if (cursnapshot == 0 &&
 359                     memcmp(newcg, cg, basesize) != 0 &&
 360                     dofix(&idesc[2], "SUMMARY INFORMATION BAD")) {
 361                         memmove(cg, newcg, (size_t)basesize);
 362                         cgdirty(cgbp);
 363                 }
 364                 if (bkgrdflag != 0 || usedsoftdep || debug)
 365                         update_maps(cg, newcg, bkgrdflag);
 366                 if (cursnapshot == 0 &&
 367                     memcmp(cg_inosused(newcg), cg_inosused(cg), mapsize) != 0 &&
 368                     dofix(&idesc[1], "BLK(S) MISSING IN BIT MAPS")) {
 369                         memmove(cg_inosused(cg), cg_inosused(newcg),
 370                               (size_t)mapsize);
 371                         cgdirty(cgbp);
 372                 }
 373         }
 374         if (cursnapshot == 0 &&
 375             memcmp(&cstotal, &fs->fs_cstotal, sizeof cstotal) != 0
 376             && dofix(&idesc[0], "SUMMARY BLK COUNT(S) WRONG IN SUPERBLK")) {
 377                 memmove(&fs->fs_cstotal, &cstotal, sizeof cstotal);
 378                 fs->fs_ronly = 0;
 379                 fs->fs_fmod = 0;
 380                 sbdirty();
 381         }
 382
 383         /*
 384          * When doing background fsck on a snapshot, figure out whether
 385          * the superblock summary is inaccurate and correct it when
 386          * necessary.
 387          */
 388         if (cursnapshot != 0) {
 389                 cmd.size = 1;
 390
 391                 cmd.value = cstotal.cs_ndir - fs->fs_cstotal.cs_ndir;
 392                 if (cmd.value != 0) {
 393                         if (debug)
 394                                 printf("adjndir by %+" PRIi64 "\n", cmd.value);
 395                         if (bkgrdsumadj == 0 || sysctl(adjndir, MIBSIZE, 0, 0,
 396                             &cmd, sizeof cmd) == -1)
 397                                 rwerror("ADJUST NUMBER OF DIRECTORIES", cmd.value);
 398                 }
 399
 400                 cmd.value = cstotal.cs_nbfree - fs->fs_cstotal.cs_nbfree;
 401                 if (cmd.value != 0) {
 402                         if (debug)
 403                                 printf("adjnbfree by %+" PRIi64 "\n", cmd.value);
 404                         if (bkgrdsumadj == 0 || sysctl(adjnbfree, MIBSIZE, 0, 0,
 405                             &cmd, sizeof cmd) == -1)
 406                                 rwerror("ADJUST NUMBER OF FREE BLOCKS", cmd.value);
 407                 }
 408
 409                 cmd.value = cstotal.cs_nifree - fs->fs_cstotal.cs_nifree;
 410                 if (cmd.value != 0) {
 411                         if (debug)
 412                                 printf("adjnifree by %+" PRIi64 "\n", cmd.value);
 413                         if (bkgrdsumadj == 0 || sysctl(adjnifree, MIBSIZE, 0, 0,
 414                             &cmd, sizeof cmd) == -1)
 415                                 rwerror("ADJUST NUMBER OF FREE INODES", cmd.value);
 416                 }
 417
 418                 cmd.value = cstotal.cs_nffree - fs->fs_cstotal.cs_nffree;
 419                 if (cmd.value != 0) {
 420                         if (debug)
 421                                 printf("adjnffree by %+" PRIi64 "\n", cmd.value);
 422                         if (bkgrdsumadj == 0 || sysctl(adjnffree, MIBSIZE, 0, 0,
 423                             &cmd, sizeof cmd) == -1)
 424                                 rwerror("ADJUST NUMBER OF FREE FRAGS", cmd.value);
 425                 }
 426
 427                 cmd.value = cstotal.cs_numclusters - fs->fs_cstotal.cs_numclusters;
 428                 if (cmd.value != 0) {
 429                         if (debug)
 430                                 printf("adjnumclusters by %+" PRIi64 "\n", cmd.value);
 431                         if (bkgrdsumadj == 0 || sysctl(adjnumclusters, MIBSIZE, 0, 0,
 432                             &cmd, sizeof cmd) == -1)
 433                                 rwerror("ADJUST NUMBER OF FREE CLUSTERS", cmd.value);
 434                 }
 435         }
 436 }
 437
 438 /*
 439  * Compare the original cylinder group inode and block bitmaps with the
 440  * updated cylinder group inode and block bitmaps. Free inodes and blocks
 441  * that have been added. Complain if any previously freed inodes blocks
 442  * are now allocated.
 443  */
 444 void
 445 update_maps(
 446         struct cg *oldcg,       /* cylinder group of claimed allocations */
 447         struct cg *newcg,       /* cylinder group of determined allocations */
 448         int usesysctl)          /* 1 => use sysctl interface to update maps */
 449 {
 450         int inomapsize, excessdirs;
 451         struct fs *fs = &sblock;
 452
 453         inomapsize = howmany(fs->fs_ipg, CHAR_BIT);
 454         excessdirs = oldcg->cg_cs.cs_ndir - newcg->cg_cs.cs_ndir;
 455         if (excessdirs < 0) {
 456                 pfatal("LOST %d DIRECTORIES\n", -excessdirs);
 457                 excessdirs = 0;
 458         }
 459         if (excessdirs > 0)
 460                 check_maps(cg_inosused(newcg), cg_inosused(oldcg), inomapsize,
 461                     oldcg->cg_cgx * (ufs2_daddr_t)fs->fs_ipg, "DIR", freedirs,
 462                     0, excessdirs, usesysctl);
 463         check_maps(cg_inosused(newcg), cg_inosused(oldcg), inomapsize,
 464             oldcg->cg_cgx * (ufs2_daddr_t)fs->fs_ipg, "FILE", freefiles,
 465             excessdirs, fs->fs_ipg, usesysctl);
 466         check_maps(cg_blksfree(oldcg), cg_blksfree(newcg),
 467             howmany(fs->fs_fpg, CHAR_BIT),
 468             oldcg->cg_cgx * (ufs2_daddr_t)fs->fs_fpg, "FRAG",
 469             freeblks, 0, fs->fs_fpg, usesysctl);
 470 }
 471
 472 static void
 473 check_maps(
 474         u_char *map1,   /* map of claimed allocations */
 475         u_char *map2,   /* map of determined allocations */
 476         int mapsize,    /* size of above two maps */
 477         ufs2_daddr_t startvalue, /* resource value for first element in map */
 478         const char *name,       /* name of resource found in maps */
 479         int *opcode,    /* sysctl opcode to free resource */
 480         int skip,       /* number of entries to skip before starting to free */
 481         int limit,      /* limit on number of entries to free */
 482         int usesysctl)  /* 1 => use sysctl interface to update maps */
 483 {
 484 #       define BUFSIZE 16
 485         char buf[BUFSIZE];
 486         long i, j, k, l, m, size;
 487         ufs2_daddr_t n, astart, aend, ustart, uend;
 488         void (*msg)(const char *fmt, ...);
 489
 490         if (usesysctl)
 491                 msg = pfatal;
 492         else
 493                 msg = pwarn;
 494         astart = ustart = aend = uend = -1;
 495         for (i = 0; i < mapsize; i++) {
 496                 j = *map1++;
 497                 k = *map2++;
 498                 if (j == k)
 499                         continue;
 500                 for (m = 0, l = 1; m < CHAR_BIT; m++, l <<= 1) {
 501                         if ((j & l) == (k & l))
 502                                 continue;
 503                         n = startvalue + i * CHAR_BIT + m;
 504                         if ((j & l) != 0) {
 505                                 if (astart == -1) {
 506                                         astart = aend = n;
 507                                         continue;
 508                                 }
 509                                 if (aend + 1 == n) {
 510                                         aend = n;
 511                                         continue;
 512                                 }
 513                                 if (astart == aend)
 514                                         (*msg)("ALLOCATED %s %" PRId64
 515                                             " MARKED FREE\n",
 516                                             name, astart);
 517                                 else
 518                                         (*msg)("%s %sS %" PRId64 "-%" PRId64
 519                                             " MARKED FREE\n",
 520                                             "ALLOCATED", name, astart, aend);
 521                                 astart = aend = n;
 522                         } else {
 523                                 if (ustart == -1) {
 524                                         ustart = uend = n;
 525                                         continue;
 526                                 }
 527                                 if (uend + 1 == n) {
 528                                         uend = n;
 529                                         continue;
 530                                 }
 531                                 size = uend - ustart + 1;
 532                                 if (size <= skip) {
 533                                         skip -= size;
 534                                         ustart = uend = n;
 535                                         continue;
 536                                 }
 537                                 if (skip > 0) {
 538                                         ustart += skip;
 539                                         size -= skip;
 540                                         skip = 0;
 541                                 }
 542                                 if (size > limit)
 543                                         size = limit;
 544                                 if (debug && size == 1)
 545                                         pwarn("%s %s %" PRId64
 546                                             " MARKED USED\n",
 547                                             "UNALLOCATED", name, ustart);
 548                                 else if (debug)
 549                                         pwarn("%s %sS %" PRId64 "-%" PRId64
 550                                             " MARKED USED\n",
 551                                             "UNALLOCATED", name, ustart,
 552                                             ustart + size - 1);
 553                                 if (usesysctl != 0) {
 554                                         cmd.value = ustart;
 555                                         cmd.size = size;
 556                                         if (sysctl(opcode, MIBSIZE, 0, 0,
 557                                             &cmd, sizeof cmd) == -1) {
 558                                                 snprintf(buf, BUFSIZE,
 559                                                     "FREE %s", name);
 560                                                 rwerror(buf, cmd.value);
 561                                         }
 562                                 }
 563                                 limit -= size;
 564                                 if (limit <= 0)
 565                                         return;
 566                                 ustart = uend = n;
 567                         }
 568                 }
 569         }
 570         if (astart != -1) {
 571                 if (astart == aend)
 572                         (*msg)("ALLOCATED %s %" PRId64
 573                             " MARKED FREE\n", name, astart);
 574                 else
 575                         (*msg)("ALLOCATED %sS %" PRId64 "-%" PRId64
 576                             " MARKED FREE\n",
 577                             name, astart, aend);
 578         }
 579         if (ustart != -1) {
 580                 size = uend - ustart + 1;
 581                 if (size <= skip)
 582                         return;
 583                 if (skip > 0) {
 584                         ustart += skip;
 585                         size -= skip;
 586                 }
 587                 if (size > limit)
 588                         size = limit;
 589                 if (debug) {
 590                         if (size == 1)
 591                                 pwarn("UNALLOCATED %s %" PRId64
 592                                     " MARKED USED\n",
 593                                     name, ustart);
 594                         else
 595                                 pwarn("UNALLOCATED %sS %" PRId64 "-%" PRId64
 596                                     " MARKED USED\n",
 597                                     name, ustart, ustart + size - 1);
 598                 }
 599                 if (usesysctl != 0) {
 600                         cmd.value = ustart;
 601                         cmd.size = size;
 602                         if (sysctl(opcode, MIBSIZE, 0, 0, &cmd,
 603                             sizeof cmd) == -1) {
 604                                 snprintf(buf, BUFSIZE, "FREE %s", name);
 605                                 rwerror(buf, cmd.value);
 606                         }
 607                 }
 608         }
 609 }
 610
 611 static void
 612 clear_blocks(ufs2_daddr_t start, ufs2_daddr_t end)
 613 {
 614
 615         if (debug)
 616                 printf("Zero frags %jd to %jd\n", start, end);
 617         if (Zflag)
 618                 blzero(fswritefd, fsbtodb(&sblock, start),
 619                     lfragtosize(&sblock, end - start + 1));
 620         if (Eflag)
 621                 blerase(fswritefd, fsbtodb(&sblock, start),
 622                     lfragtosize(&sblock, end - start + 1));
 623 }