1 /* $NetBSD: setup.c,v 1.12 2000/01/28 16:01:46 bouyer Exp $ */ 2 3 /* 4 * Copyright (c) 1997 Manuel Bouyer. 5 * Copyright (c) 1980, 1986, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 */ 36 37 #include <sys/cdefs.h> 38 #ifndef lint 39 #if 0 40 static char sccsid[] = "@(#)setup.c 8.5 (Berkeley) 11/23/94"; 41 #else 42 __RCSID("$NetBSD: setup.c,v 1.12 2000/01/28 16:01:46 bouyer Exp $"); 43 #endif 44 #endif /* not lint */ 45 46 #define FSTYPENAMES 47 #include <sys/param.h> 48 #include <sys/time.h> 49 #include <ufs/ext2fs/ext2fs_dinode.h> 50 #include <ufs/ext2fs/ext2fs.h> 51 #include <sys/stat.h> 52 #include <sys/ioctl.h> 53 #include <sys/disklabel.h> 54 #include <sys/file.h> 55 56 #include <errno.h> 57 #include <stdio.h> 58 #include <stdlib.h> 59 #include <string.h> 60 #include <ctype.h> 61 62 #include "fsck.h" 63 #include "extern.h" 64 #include "fsutil.h" 65 66 #define POWEROF2(num) (((num) & ((num) - 1)) == 0) 67 68 void badsb __P((int, char *)); 69 int calcsb __P((const char *, int, struct m_ext2fs *)); 70 static struct disklabel *getdisklabel __P((const char *, int)); 71 static int readsb __P((int)); 72 73 int 74 setup(dev) 75 const char *dev; 76 { 77 long cg, asked, i; 78 long bmapsize; 79 struct disklabel *lp; 80 off_t sizepb; 81 struct stat statb; 82 struct m_ext2fs proto; 83 int doskipclean; 84 u_int64_t maxfilesize; 85 86 havesb = 0; 87 fswritefd = -1; 88 doskipclean = skipclean; 89 if (stat(dev, &statb) < 0) { 90 printf("Can't stat %s: %s\n", dev, strerror(errno)); 91 return (0); 92 } 93 if (!S_ISCHR(statb.st_mode)) { 94 pfatal("%s is not a character device", dev); 95 if (reply("CONTINUE") == 0) 96 return (0); 97 } 98 if ((fsreadfd = open(dev, O_RDONLY)) < 0) { 99 printf("Can't open %s: %s\n", dev, strerror(errno)); 100 return (0); 101 } 102 if (preen == 0) 103 printf("** %s", dev); 104 if (nflag || (fswritefd = open(dev, O_WRONLY)) < 0) { 105 fswritefd = -1; 106 if (preen) 107 pfatal("NO WRITE ACCESS"); 108 printf(" (NO WRITE)"); 109 } 110 if (preen == 0) 111 printf("\n"); 112 fsmodified = 0; 113 lfdir = 0; 114 initbarea(&sblk); 115 initbarea(&asblk); 116 sblk.b_un.b_buf = malloc(SBSIZE); 117 asblk.b_un.b_buf = malloc(SBSIZE); 118 if (sblk.b_un.b_buf == NULL || asblk.b_un.b_buf == NULL) 119 errexit("cannot allocate space for superblock\n"); 120 if ((lp = getdisklabel((char *)NULL, fsreadfd)) != NULL) 121 dev_bsize = secsize = lp->d_secsize; 122 else 123 dev_bsize = secsize = DEV_BSIZE; 124 /* 125 * Read in the superblock, looking for alternates if necessary 126 */ 127 if (readsb(1) == 0) { 128 if (bflag || preen || calcsb(dev, fsreadfd, &proto) == 0) 129 return(0); 130 if (reply("LOOK FOR ALTERNATE SUPERBLOCKS") == 0) 131 return (0); 132 for (cg = 1; cg < proto.e2fs_ncg; cg++) { 133 bflag = fsbtodb(&proto, 134 cg * proto.e2fs.e2fs_bpg + proto.e2fs.e2fs_first_dblock); 135 if (readsb(0) != 0) 136 break; 137 } 138 if (cg >= proto.e2fs_ncg) { 139 printf("%s %s\n%s %s\n%s %s\n", 140 "SEARCH FOR ALTERNATE SUPER-BLOCK", 141 "FAILED. YOU MUST USE THE", 142 "-b OPTION TO FSCK_FFS TO SPECIFY THE", 143 "LOCATION OF AN ALTERNATE", 144 "SUPER-BLOCK TO SUPPLY NEEDED", 145 "INFORMATION; SEE fsck_ext2fs(8)."); 146 return(0); 147 } 148 doskipclean = 0; 149 pwarn("USING ALTERNATE SUPERBLOCK AT %d\n", bflag); 150 } 151 if (debug) 152 printf("state = %d\n", sblock.e2fs.e2fs_state); 153 if (sblock.e2fs.e2fs_state == E2FS_ISCLEAN) { 154 if (doskipclean) { 155 pwarn("%sile system is clean; not checking\n", 156 preen ? "f" : "** F"); 157 return (-1); 158 } 159 if (!preen) 160 pwarn("** File system is already clean\n"); 161 } 162 maxfsblock = sblock.e2fs.e2fs_bcount; 163 maxino = sblock.e2fs_ncg * sblock.e2fs.e2fs_ipg; 164 sizepb = sblock.e2fs_bsize; 165 maxfilesize = sblock.e2fs_bsize * NDADDR - 1; 166 for (i = 0; i < NIADDR; i++) { 167 sizepb *= NINDIR(&sblock); 168 maxfilesize += sizepb; 169 } 170 /* 171 * Check and potentially fix certain fields in the super block. 172 */ 173 if ((sblock.e2fs.e2fs_rbcount < 0) || 174 (sblock.e2fs.e2fs_rbcount > sblock.e2fs.e2fs_bcount)) { 175 pfatal("IMPOSSIBLE RESERVED BLOCK COUNT=%d IN SUPERBLOCK", 176 sblock.e2fs.e2fs_rbcount); 177 if (reply("SET TO DEFAULT") == 1) { 178 sblock.e2fs.e2fs_rbcount = sblock.e2fs.e2fs_bcount * 0.1; 179 sbdirty(); 180 dirty(&asblk); 181 } 182 } 183 if (sblock.e2fs.e2fs_bpg != sblock.e2fs.e2fs_fpg) { 184 pfatal("WRONG FPG=%d (BPG=%d) IN SUPERBLOCK", 185 sblock.e2fs.e2fs_fpg, sblock.e2fs.e2fs_bpg); 186 return 0; 187 } 188 if (asblk.b_dirty && !bflag) { 189 copyback_sb(&asblk); 190 flush(fswritefd, &asblk); 191 } 192 /* 193 * read in the summary info. 194 */ 195 196 sblock.e2fs_gd = malloc(sblock.e2fs_ngdb * sblock.e2fs_bsize); 197 if (sblock.e2fs_gd == NULL) 198 errexit("out of memory\n"); 199 asked = 0; 200 for (i=0; i < sblock.e2fs_ngdb; i++) { 201 if (bread(fsreadfd,(char *) 202 &sblock.e2fs_gd[i* sblock.e2fs_bsize / sizeof(struct ext2_gd)], 203 fsbtodb(&sblock, ((sblock.e2fs_bsize>1024)?0:1)+i+1), 204 sblock.e2fs_bsize) != 0 && !asked) { 205 pfatal("BAD SUMMARY INFORMATION"); 206 if (reply("CONTINUE") == 0) 207 errexit("%s\n", ""); 208 asked++; 209 } 210 } 211 /* 212 * allocate and initialize the necessary maps 213 */ 214 bmapsize = roundup(howmany(maxfsblock, NBBY), sizeof(int16_t)); 215 blockmap = calloc((unsigned)bmapsize, sizeof (char)); 216 if (blockmap == NULL) { 217 printf("cannot alloc %u bytes for blockmap\n", 218 (unsigned)bmapsize); 219 goto badsblabel; 220 } 221 statemap = calloc((unsigned)(maxino + 2), sizeof(char)); 222 if (statemap == NULL) { 223 printf("cannot alloc %u bytes for statemap\n", 224 (unsigned)(maxino + 1)); 225 goto badsblabel; 226 } 227 typemap = calloc((unsigned)(maxino + 1), sizeof(char)); 228 if (typemap == NULL) { 229 printf("cannot alloc %u bytes for typemap\n", 230 (unsigned)(maxino + 1)); 231 goto badsblabel; 232 } 233 lncntp = (int16_t *)calloc((unsigned)(maxino + 1), sizeof(int16_t)); 234 if (lncntp == NULL) { 235 printf("cannot alloc %u bytes for lncntp\n", 236 (unsigned)((maxino + 1) * sizeof(int16_t))); 237 goto badsblabel; 238 } 239 for (numdirs = 0, cg = 0; cg < sblock.e2fs_ncg; cg++) { 240 numdirs += fs2h16(sblock.e2fs_gd[cg].ext2bgd_ndirs); 241 } 242 inplast = 0; 243 listmax = numdirs + 10; 244 inpsort = (struct inoinfo **)calloc((unsigned)listmax, 245 sizeof(struct inoinfo *)); 246 inphead = (struct inoinfo **)calloc((unsigned)numdirs, 247 sizeof(struct inoinfo *)); 248 if (inpsort == NULL || inphead == NULL) { 249 printf("cannot alloc %u bytes for inphead\n", 250 (unsigned)(numdirs * sizeof(struct inoinfo *))); 251 goto badsblabel; 252 } 253 bufinit(); 254 return (1); 255 256 badsblabel: 257 ckfini(0); 258 return (0); 259 } 260 261 /* 262 * Read in the super block and its summary info, convert to host byte order. 263 */ 264 static int 265 readsb(listerr) 266 int listerr; 267 { 268 daddr_t super = bflag ? bflag : SBOFF / dev_bsize; 269 270 if (bread(fsreadfd, (char *)sblk.b_un.b_fs, super, (long)SBSIZE) != 0) 271 return (0); 272 sblk.b_bno = super; 273 sblk.b_size = SBSIZE; 274 275 /* Copy the superblock in memory */ 276 e2fs_sbload(sblk.b_un.b_fs, &sblock.e2fs); 277 278 /* 279 * run a few consistency checks of the super block 280 */ 281 if (sblock.e2fs.e2fs_magic != E2FS_MAGIC) { 282 badsb(listerr, "MAGIC NUMBER WRONG"); return (0); 283 } 284 if (sblock.e2fs.e2fs_log_bsize > 2) { 285 badsb(listerr, "BAD LOG_BSIZE"); return (0); 286 } 287 288 /* compute the dynamic fields of the in-memory sb */ 289 /* compute dynamic sb infos */ 290 sblock.e2fs_ncg = 291 howmany(sblock.e2fs.e2fs_bcount - sblock.e2fs.e2fs_first_dblock, 292 sblock.e2fs.e2fs_bpg); 293 /* XXX assume hw bsize = 512 */ 294 sblock.e2fs_fsbtodb = sblock.e2fs.e2fs_log_bsize + 1; 295 sblock.e2fs_bsize = 1024 << sblock.e2fs.e2fs_log_bsize; 296 sblock.e2fs_bshift = LOG_MINBSIZE + sblock.e2fs.e2fs_log_bsize; 297 sblock.e2fs_qbmask = sblock.e2fs_bsize - 1; 298 sblock.e2fs_bmask = ~sblock.e2fs_qbmask; 299 sblock.e2fs_ngdb = howmany(sblock.e2fs_ncg, 300 sblock.e2fs_bsize / sizeof(struct ext2_gd)); 301 sblock.e2fs_ipb = sblock.e2fs_bsize / sizeof(struct ext2fs_dinode); 302 sblock.e2fs_itpg = sblock.e2fs.e2fs_ipg/sblock.e2fs_ipb; 303 304 /* 305 * Compute block size that the filesystem is based on, 306 * according to fsbtodb, and adjust superblock block number 307 * so we can tell if this is an alternate later. 308 */ 309 super *= dev_bsize; 310 dev_bsize = sblock.e2fs_bsize / fsbtodb(&sblock, 1); 311 sblk.b_bno = super / dev_bsize; 312 313 getblk(&asblk, 1 * sblock.e2fs.e2fs_bpg + sblock.e2fs.e2fs_first_dblock, 314 (long)SBSIZE); 315 if (asblk.b_errs) 316 return (0); 317 if (bflag) { 318 havesb = 1; 319 return (1); 320 } 321 322 /* 323 * Set all possible fields that could differ, then do check 324 * of whole super block against an alternate super block. 325 * When an alternate super-block is specified this check is skipped. 326 */ 327 asblk.b_un.b_fs->e2fs_rbcount = sblk.b_un.b_fs->e2fs_rbcount; 328 asblk.b_un.b_fs->e2fs_fbcount = sblk.b_un.b_fs->e2fs_fbcount; 329 asblk.b_un.b_fs->e2fs_ficount = sblk.b_un.b_fs->e2fs_ficount; 330 asblk.b_un.b_fs->e2fs_mtime = sblk.b_un.b_fs->e2fs_mtime; 331 asblk.b_un.b_fs->e2fs_wtime = sblk.b_un.b_fs->e2fs_wtime; 332 asblk.b_un.b_fs->e2fs_mnt_count = sblk.b_un.b_fs->e2fs_mnt_count; 333 asblk.b_un.b_fs->e2fs_max_mnt_count = sblk.b_un.b_fs->e2fs_max_mnt_count; 334 asblk.b_un.b_fs->e2fs_state = sblk.b_un.b_fs->e2fs_state; 335 asblk.b_un.b_fs->e2fs_beh = sblk.b_un.b_fs->e2fs_beh; 336 asblk.b_un.b_fs->e2fs_lastfsck = sblk.b_un.b_fs->e2fs_lastfsck; 337 asblk.b_un.b_fs->e2fs_fsckintv = sblk.b_un.b_fs->e2fs_fsckintv; 338 asblk.b_un.b_fs->e2fs_ruid = sblk.b_un.b_fs->e2fs_ruid; 339 asblk.b_un.b_fs->e2fs_rgid = sblk.b_un.b_fs->e2fs_rgid; 340 asblk.b_un.b_fs->e2fs_block_group_nr = 341 sblk.b_un.b_fs->e2fs_block_group_nr; 342 if (sblock.e2fs.e2fs_rev > E2FS_REV0 && 343 ((sblock.e2fs.e2fs_features_incompat & ~EXT2F_INCOMPAT_SUPP) || 344 (sblock.e2fs.e2fs_features_rocompat & ~EXT2F_ROCOMPAT_SUPP))) { 345 if (debug) { 346 printf("compat 0x%08x, incompat 0x%08x, compat_ro " 347 "0x%08x\n", 348 sblock.e2fs.e2fs_features_compat, 349 sblock.e2fs.e2fs_features_incompat, 350 sblock.e2fs.e2fs_features_rocompat); 351 } 352 badsb(listerr,"INCOMPATIBLE FEATURE BITS IN SUPER BLOCK"); 353 return 0; 354 } 355 if (memcmp(sblk.b_un.b_fs, asblk.b_un.b_fs, SBSIZE)) { 356 if (debug) { 357 u_int32_t *nlp, *olp, *endlp; 358 359 printf("superblock mismatches\n"); 360 nlp = (u_int32_t *)asblk.b_un.b_fs; 361 olp = (u_int32_t *)sblk.b_un.b_fs; 362 endlp = olp + (SBSIZE / sizeof *olp); 363 for ( ; olp < endlp; olp++, nlp++) { 364 if (*olp == *nlp) 365 continue; 366 printf("offset %ld, original %ld, alternate %ld\n", 367 (long)(olp - (u_int32_t *)sblk.b_un.b_fs), 368 (long)fs2h32(*olp), 369 (long)fs2h32(*nlp)); 370 } 371 } 372 badsb(listerr, 373 "VALUES IN SUPER BLOCK DISAGREE WITH THOSE IN FIRST ALTERNATE"); 374 return (0); 375 } 376 havesb = 1; 377 return (1); 378 } 379 380 void 381 copyback_sb(bp) 382 struct bufarea *bp; 383 { 384 /* Copy the in-memory superblock back to buffer */ 385 bp->b_un.b_fs->e2fs_icount = fs2h32(sblock.e2fs.e2fs_icount); 386 bp->b_un.b_fs->e2fs_bcount = fs2h32(sblock.e2fs.e2fs_bcount); 387 bp->b_un.b_fs->e2fs_rbcount = fs2h32(sblock.e2fs.e2fs_rbcount); 388 bp->b_un.b_fs->e2fs_fbcount = fs2h32(sblock.e2fs.e2fs_fbcount); 389 bp->b_un.b_fs->e2fs_ficount = fs2h32(sblock.e2fs.e2fs_ficount); 390 bp->b_un.b_fs->e2fs_first_dblock = 391 fs2h32(sblock.e2fs.e2fs_first_dblock); 392 bp->b_un.b_fs->e2fs_log_bsize = fs2h32(sblock.e2fs.e2fs_log_bsize); 393 bp->b_un.b_fs->e2fs_fsize = fs2h32(sblock.e2fs.e2fs_fsize); 394 bp->b_un.b_fs->e2fs_bpg = fs2h32(sblock.e2fs.e2fs_bpg); 395 bp->b_un.b_fs->e2fs_fpg = fs2h32(sblock.e2fs.e2fs_fpg); 396 bp->b_un.b_fs->e2fs_ipg = fs2h32(sblock.e2fs.e2fs_ipg); 397 bp->b_un.b_fs->e2fs_mtime = fs2h32(sblock.e2fs.e2fs_mtime); 398 bp->b_un.b_fs->e2fs_wtime = fs2h32(sblock.e2fs.e2fs_wtime); 399 bp->b_un.b_fs->e2fs_lastfsck = fs2h32(sblock.e2fs.e2fs_lastfsck); 400 bp->b_un.b_fs->e2fs_fsckintv = fs2h32(sblock.e2fs.e2fs_fsckintv); 401 bp->b_un.b_fs->e2fs_creator = fs2h32(sblock.e2fs.e2fs_creator); 402 bp->b_un.b_fs->e2fs_rev = fs2h32(sblock.e2fs.e2fs_rev); 403 bp->b_un.b_fs->e2fs_mnt_count = fs2h16(sblock.e2fs.e2fs_mnt_count); 404 bp->b_un.b_fs->e2fs_max_mnt_count = 405 fs2h16(sblock.e2fs.e2fs_max_mnt_count); 406 bp->b_un.b_fs->e2fs_magic = fs2h16(sblock.e2fs.e2fs_magic); 407 bp->b_un.b_fs->e2fs_state = fs2h16(sblock.e2fs.e2fs_state); 408 bp->b_un.b_fs->e2fs_beh = fs2h16(sblock.e2fs.e2fs_beh); 409 bp->b_un.b_fs->e2fs_ruid = fs2h16(sblock.e2fs.e2fs_ruid); 410 bp->b_un.b_fs->e2fs_rgid = fs2h16(sblock.e2fs.e2fs_rgid); 411 } 412 413 void 414 badsb(listerr, s) 415 int listerr; 416 char *s; 417 { 418 419 if (!listerr) 420 return; 421 if (preen) 422 printf("%s: ", cdevname()); 423 pfatal("BAD SUPER BLOCK: %s\n", s); 424 } 425 426 /* 427 * Calculate a prototype superblock based on information in the disk label. 428 * When done the cgsblock macro can be calculated and the fs_ncg field 429 * can be used. Do NOT attempt to use other macros without verifying that 430 * their needed information is available! 431 */ 432 433 int 434 calcsb(dev, devfd, fs) 435 const char *dev; 436 int devfd; 437 struct m_ext2fs *fs; 438 { 439 struct disklabel *lp; 440 struct partition *pp; 441 char *cp; 442 443 cp = strchr(dev, '\0') - 1; 444 if ((cp == (char *)-1 || (*cp < 'a' || *cp > 'h')) && !isdigit(*cp)) { 445 pfatal("%s: CANNOT FIGURE OUT FILE SYSTEM PARTITION\n", dev); 446 return (0); 447 } 448 lp = getdisklabel(dev, devfd); 449 if (isdigit(*cp)) 450 pp = &lp->d_partitions[0]; 451 else 452 pp = &lp->d_partitions[*cp - 'a']; 453 if (pp->p_fstype != FS_EX2FS) { 454 pfatal("%s: NOT LABELED AS A EXT2 FILE SYSTEM (%s)\n", 455 dev, pp->p_fstype < FSMAXTYPES ? 456 fstypenames[pp->p_fstype] : "unknown"); 457 return (0); 458 } 459 memset(fs, 0, sizeof(struct m_ext2fs)); 460 fs->e2fs_bsize = pp->p_fsize; 461 fs->e2fs.e2fs_log_bsize = pp->p_fsize / 1024; 462 fs->e2fs.e2fs_bcount = (pp->p_size * DEV_BSIZE) / fs->e2fs_bsize; 463 fs->e2fs.e2fs_first_dblock = (fs->e2fs.e2fs_log_bsize == 0) ? 1 : 0; 464 fs->e2fs.e2fs_bpg = fs->e2fs_bsize * NBBY; 465 fs->e2fs_bshift = LOG_MINBSIZE + fs->e2fs.e2fs_log_bsize; 466 fs->e2fs_qbmask = fs->e2fs_bsize - 1; 467 fs->e2fs_bmask = ~fs->e2fs_qbmask; 468 fs->e2fs_ncg = 469 howmany(fs->e2fs.e2fs_bcount - fs->e2fs.e2fs_first_dblock, 470 fs->e2fs.e2fs_bpg); 471 fs->e2fs_fsbtodb = fs->e2fs.e2fs_log_bsize + 1; 472 fs->e2fs_ngdb = howmany(fs->e2fs_ncg, 473 fs->e2fs_bsize / sizeof(struct ext2_gd)); 474 475 return (1); 476 } 477 478 static struct disklabel * 479 getdisklabel(s, fd) 480 const char *s; 481 int fd; 482 { 483 static struct disklabel lab; 484 485 if (ioctl(fd, DIOCGDINFO, (char *)&lab) < 0) { 486 if (s == NULL) 487 return ((struct disklabel *)NULL); 488 pwarn("ioctl (GCINFO): %s\n", strerror(errno)); 489 errexit("%s: can't read disk label\n", s); 490 } 491 return (&lab); 492 } 493 494 daddr_t 495 cgoverhead(c) 496 int c; 497 { 498 int overh; 499 overh = 1 /* block bitmap */ + 500 1 /* inode bitmap */ + 501 sblock.e2fs_itpg; 502 if (sblock.e2fs.e2fs_rev > E2FS_REV0 && 503 sblock.e2fs.e2fs_features_rocompat & EXT2F_ROCOMPAT_SPARSESUPER) { 504 if (cg_has_sb(c) == 0) 505 return overh; 506 } 507 overh += 1 + sblock.e2fs_ngdb; 508 return overh; 509 } 510