1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1982, 1986, 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 #include <sys/cdefs.h> 33 #include <sys/param.h> 34 #include <sys/endian.h> 35 #include <sys/limits.h> 36 37 #ifndef _KERNEL 38 #include <stdio.h> 39 #include <string.h> 40 #include <stdlib.h> 41 #include <time.h> 42 #include <sys/errno.h> 43 #include <ufs/ufs/dinode.h> 44 #include <ufs/ffs/fs.h> 45 46 uint32_t calculate_crc32c(uint32_t, const void *, size_t); 47 uint32_t ffs_calc_sbhash(struct fs *); 48 struct malloc_type; 49 #define UFS_MALLOC(size, type, flags) malloc(size) 50 #define UFS_FREE(ptr, type) free(ptr) 51 #define maxphys MAXPHYS 52 53 #else /* _KERNEL */ 54 #include <sys/systm.h> 55 #include <sys/gsb_crc32.h> 56 #include <sys/lock.h> 57 #include <sys/malloc.h> 58 #include <sys/mount.h> 59 #include <sys/vnode.h> 60 #include <sys/bio.h> 61 #include <sys/buf.h> 62 #include <sys/ucred.h> 63 64 #include <ufs/ufs/quota.h> 65 #include <ufs/ufs/inode.h> 66 #include <ufs/ufs/extattr.h> 67 #include <ufs/ufs/ufsmount.h> 68 #include <ufs/ufs/ufs_extern.h> 69 #include <ufs/ffs/ffs_extern.h> 70 #include <ufs/ffs/fs.h> 71 72 #define UFS_MALLOC(size, type, flags) malloc(size, type, flags) 73 #define UFS_FREE(ptr, type) free(ptr, type) 74 75 #endif /* _KERNEL */ 76 77 /* 78 * Verify an inode check-hash. 79 */ 80 int 81 ffs_verify_dinode_ckhash(struct fs *fs, struct ufs2_dinode *dip) 82 { 83 uint32_t ckhash, save_ckhash; 84 85 /* 86 * Return success if unallocated or we are not doing inode check-hash. 87 */ 88 if (dip->di_mode == 0 || (fs->fs_metackhash & CK_INODE) == 0) 89 return (0); 90 /* 91 * Exclude di_ckhash from the crc32 calculation, e.g., always use 92 * a check-hash value of zero when calculating the check-hash. 93 */ 94 save_ckhash = dip->di_ckhash; 95 dip->di_ckhash = 0; 96 ckhash = calculate_crc32c(~0L, (void *)dip, sizeof(*dip)); 97 dip->di_ckhash = save_ckhash; 98 if (save_ckhash == ckhash) 99 return (0); 100 return (EINVAL); 101 } 102 103 /* 104 * Update an inode check-hash. 105 */ 106 void 107 ffs_update_dinode_ckhash(struct fs *fs, struct ufs2_dinode *dip) 108 { 109 110 if (dip->di_mode == 0 || (fs->fs_metackhash & CK_INODE) == 0) 111 return; 112 /* 113 * Exclude old di_ckhash from the crc32 calculation, e.g., always use 114 * a check-hash value of zero when calculating the new check-hash. 115 */ 116 dip->di_ckhash = 0; 117 dip->di_ckhash = calculate_crc32c(~0L, (void *)dip, sizeof(*dip)); 118 } 119 120 /* 121 * These are the low-level functions that actually read and write 122 * the superblock and its associated data. 123 */ 124 static off_t sblock_try[] = SBLOCKSEARCH; 125 static int readsuper(void *, struct fs **, off_t, int, 126 int (*)(void *, off_t, void **, int)); 127 static int validate_sblock(struct fs *, int); 128 129 /* 130 * Read a superblock from the devfd device. 131 * 132 * If an alternate superblock is specified, it is read. Otherwise the 133 * set of locations given in the SBLOCKSEARCH list is searched for a 134 * superblock. Memory is allocated for the superblock by the readfunc and 135 * is returned. If filltype is non-NULL, additional memory is allocated 136 * of type filltype and filled in with the superblock summary information. 137 * All memory is freed when any error is returned. 138 * 139 * If a superblock is found, zero is returned. Otherwise one of the 140 * following error values is returned: 141 * EIO: non-existent or truncated superblock. 142 * EIO: error reading summary information. 143 * ENOENT: no usable known superblock found. 144 * EILSEQ: filesystem with wrong byte order found. 145 * ENOMEM: failed to allocate space for the superblock. 146 * EINVAL: The previous newfs operation on this volume did not complete. 147 * The administrator must complete newfs before using this volume. 148 */ 149 int 150 ffs_sbget(void *devfd, struct fs **fsp, off_t sblock, int flags, 151 struct malloc_type *filltype, 152 int (*readfunc)(void *devfd, off_t loc, void **bufp, int size)) 153 { 154 struct fs *fs; 155 struct fs_summary_info *fs_si; 156 int i, error; 157 uint64_t size, blks; 158 uint8_t *space; 159 int32_t *lp; 160 char *buf; 161 162 fs = NULL; 163 *fsp = NULL; 164 if (sblock != UFS_STDSB) { 165 if ((error = readsuper(devfd, &fs, sblock, 166 flags | UFS_ALTSBLK, readfunc)) != 0) { 167 if (fs != NULL) 168 UFS_FREE(fs, filltype); 169 return (error); 170 } 171 } else { 172 for (i = 0; sblock_try[i] != -1; i++) { 173 if ((error = readsuper(devfd, &fs, sblock_try[i], 174 flags, readfunc)) == 0) { 175 if ((flags & UFS_NOCSUM) != 0) { 176 *fsp = fs; 177 return (0); 178 } 179 break; 180 } 181 if (fs != NULL) { 182 UFS_FREE(fs, filltype); 183 fs = NULL; 184 } 185 if (error == ENOENT) 186 continue; 187 return (error); 188 } 189 if (sblock_try[i] == -1) 190 return (ENOENT); 191 } 192 /* 193 * Read in the superblock summary information. 194 */ 195 size = fs->fs_cssize; 196 blks = howmany(size, fs->fs_fsize); 197 if (fs->fs_contigsumsize > 0) 198 size += fs->fs_ncg * sizeof(int32_t); 199 size += fs->fs_ncg * sizeof(uint8_t); 200 if ((fs_si = UFS_MALLOC(sizeof(*fs_si), filltype, M_NOWAIT)) == NULL) { 201 UFS_FREE(fs, filltype); 202 return (ENOMEM); 203 } 204 bzero(fs_si, sizeof(*fs_si)); 205 fs->fs_si = fs_si; 206 if ((space = UFS_MALLOC(size, filltype, M_NOWAIT)) == NULL) { 207 UFS_FREE(fs->fs_si, filltype); 208 UFS_FREE(fs, filltype); 209 return (ENOMEM); 210 } 211 fs->fs_csp = (struct csum *)space; 212 for (i = 0; i < blks; i += fs->fs_frag) { 213 size = fs->fs_bsize; 214 if (i + fs->fs_frag > blks) 215 size = (blks - i) * fs->fs_fsize; 216 buf = NULL; 217 error = (*readfunc)(devfd, 218 dbtob(fsbtodb(fs, fs->fs_csaddr + i)), (void **)&buf, size); 219 if (error) { 220 if (buf != NULL) 221 UFS_FREE(buf, filltype); 222 UFS_FREE(fs->fs_csp, filltype); 223 UFS_FREE(fs->fs_si, filltype); 224 UFS_FREE(fs, filltype); 225 return (error); 226 } 227 memcpy(space, buf, size); 228 UFS_FREE(buf, filltype); 229 space += size; 230 } 231 if (fs->fs_contigsumsize > 0) { 232 fs->fs_maxcluster = lp = (int32_t *)space; 233 for (i = 0; i < fs->fs_ncg; i++) 234 *lp++ = fs->fs_contigsumsize; 235 space = (uint8_t *)lp; 236 } 237 size = fs->fs_ncg * sizeof(uint8_t); 238 fs->fs_contigdirs = (uint8_t *)space; 239 bzero(fs->fs_contigdirs, size); 240 *fsp = fs; 241 return (0); 242 } 243 244 /* 245 * Try to read a superblock from the location specified by sblockloc. 246 * Return zero on success or an errno on failure. 247 */ 248 static int 249 readsuper(void *devfd, struct fs **fsp, off_t sblockloc, int flags, 250 int (*readfunc)(void *devfd, off_t loc, void **bufp, int size)) 251 { 252 struct fs *fs; 253 int error, res; 254 uint32_t ckhash; 255 256 error = (*readfunc)(devfd, sblockloc, (void **)fsp, SBLOCKSIZE); 257 if (error != 0) 258 return (error); 259 fs = *fsp; 260 if (fs->fs_magic == FS_BAD_MAGIC) 261 return (EINVAL); 262 /* 263 * For UFS1 with a 65536 block size, the first backup superblock 264 * is at the same location as the UFS2 superblock. Since SBLOCK_UFS2 265 * is the first location checked, the first backup is the superblock 266 * that will be accessed. Here we fail the lookup so that we can 267 * retry with the correct location for the UFS1 superblock. 268 */ 269 if (fs->fs_magic == FS_UFS1_MAGIC && (flags & UFS_ALTSBLK) == 0 && 270 fs->fs_bsize == SBLOCK_UFS2 && sblockloc == SBLOCK_UFS2) 271 return (ENOENT); 272 if ((error = validate_sblock(fs, flags)) > 0) 273 return (error); 274 /* 275 * If the filesystem has been run on a kernel without 276 * metadata check hashes, disable them. 277 */ 278 if ((fs->fs_flags & FS_METACKHASH) == 0) 279 fs->fs_metackhash = 0; 280 /* 281 * Clear any check-hashes that are not maintained 282 * by this kernel. Also clear any unsupported flags. 283 */ 284 fs->fs_metackhash &= CK_SUPPORTED; 285 fs->fs_flags &= FS_SUPPORTED; 286 if (fs->fs_ckhash != (ckhash = ffs_calc_sbhash(fs))) { 287 if ((flags & (UFS_NOMSG | UFS_NOHASHFAIL)) == 288 (UFS_NOMSG | UFS_NOHASHFAIL)) 289 return (0); 290 if ((flags & UFS_NOMSG) != 0) 291 return (EINTEGRITY); 292 #ifdef _KERNEL 293 res = uprintf("Superblock check-hash failed: recorded " 294 "check-hash 0x%x != computed check-hash 0x%x%s\n", 295 fs->fs_ckhash, ckhash, 296 (flags & UFS_NOHASHFAIL) != 0 ? " (Ignored)" : ""); 297 #else 298 res = 0; 299 #endif 300 /* 301 * Print check-hash failure if no controlling terminal 302 * in kernel or always if in user-mode (libufs). 303 */ 304 if (res == 0) 305 printf("Superblock check-hash failed: recorded " 306 "check-hash 0x%x != computed check-hash " 307 "0x%x%s\n", fs->fs_ckhash, ckhash, 308 (flags & UFS_NOHASHFAIL) ? " (Ignored)" : ""); 309 if ((flags & UFS_NOHASHFAIL) != 0) 310 return (0); 311 return (EINTEGRITY); 312 } 313 /* Have to set for old filesystems that predate this field */ 314 fs->fs_sblockactualloc = sblockloc; 315 /* Not yet any summary information */ 316 fs->fs_si = NULL; 317 return (0); 318 } 319 320 /* 321 * Verify the filesystem values. 322 */ 323 #define ILOG2(num) (fls(num) - 1) 324 #ifdef STANDALONE_SMALL 325 #define MPRINT(...) do { } while (0) 326 #else 327 #define MPRINT(...) if (prtmsg) printf(__VA_ARGS__) 328 #endif 329 #define FCHK(lhs, op, rhs, fmt) \ 330 if (lhs op rhs) { \ 331 MPRINT("UFS%d superblock failed: %s (" #fmt ") %s %s (" \ 332 #fmt ")\n", fs->fs_magic == FS_UFS1_MAGIC ? 1 : 2, \ 333 #lhs, (intmax_t)lhs, #op, #rhs, (intmax_t)rhs); \ 334 if (error < 0) \ 335 return (ENOENT); \ 336 if (error == 0) \ 337 error = ENOENT; \ 338 } 339 #define WCHK(lhs, op, rhs, fmt) \ 340 if (lhs op rhs) { \ 341 MPRINT("UFS%d superblock failed: %s (" #fmt ") %s %s (" \ 342 #fmt ")%s\n", fs->fs_magic == FS_UFS1_MAGIC ? 1 : 2,\ 343 #lhs, (intmax_t)lhs, #op, #rhs, (intmax_t)rhs, wmsg);\ 344 if (error == 0) \ 345 error = warnerr; \ 346 if (warnerr == 0) \ 347 lhs = rhs; \ 348 } 349 #define FCHK2(lhs1, op1, rhs1, lhs2, op2, rhs2, fmt) \ 350 if (lhs1 op1 rhs1 && lhs2 op2 rhs2) { \ 351 MPRINT("UFS%d superblock failed: %s (" #fmt ") %s %s (" \ 352 #fmt ") && %s (" #fmt ") %s %s (" #fmt ")\n", \ 353 fs->fs_magic == FS_UFS1_MAGIC ? 1 : 2, #lhs1, \ 354 (intmax_t)lhs1, #op1, #rhs1, (intmax_t)rhs1, #lhs2, \ 355 (intmax_t)lhs2, #op2, #rhs2, (intmax_t)rhs2); \ 356 if (error < 0) \ 357 return (ENOENT); \ 358 if (error == 0) \ 359 error = ENOENT; \ 360 } 361 362 static int 363 validate_sblock(struct fs *fs, int flags) 364 { 365 uint64_t i, sectorsize; 366 uint64_t maxfilesize, sizepb; 367 int error, prtmsg, warnerr; 368 char *wmsg; 369 370 error = 0; 371 sectorsize = dbtob(1); 372 prtmsg = ((flags & UFS_NOMSG) == 0); 373 warnerr = (flags & UFS_NOWARNFAIL) == UFS_NOWARNFAIL ? 0 : ENOENT; 374 wmsg = warnerr ? "" : " (Ignored)"; 375 /* 376 * Check for endian mismatch between machine and filesystem. 377 */ 378 if (((fs->fs_magic != FS_UFS2_MAGIC) && 379 (bswap32(fs->fs_magic) == FS_UFS2_MAGIC)) || 380 ((fs->fs_magic != FS_UFS1_MAGIC) && 381 (bswap32(fs->fs_magic) == FS_UFS1_MAGIC))) { 382 MPRINT("UFS superblock failed due to endian mismatch " 383 "between machine and filesystem\n"); 384 return(EILSEQ); 385 } 386 /* 387 * If just validating for recovery, then do just the minimal 388 * checks needed for the superblock fields needed to find 389 * alternate superblocks. 390 */ 391 if ((flags & UFS_FSRONLY) == UFS_FSRONLY && 392 (fs->fs_magic == FS_UFS1_MAGIC || fs->fs_magic == FS_UFS2_MAGIC)) { 393 error = -1; /* fail on first error */ 394 if (fs->fs_magic == FS_UFS2_MAGIC) { 395 FCHK(fs->fs_sblockloc, !=, SBLOCK_UFS2, %#jx); 396 } else if (fs->fs_magic == FS_UFS1_MAGIC) { 397 FCHK(fs->fs_sblockloc, <, 0, %jd); 398 FCHK(fs->fs_sblockloc, >, SBLOCK_UFS1, %jd); 399 FCHK(fs->fs_old_ncyl, !=, fs->fs_ncg, %jd); 400 } 401 FCHK(fs->fs_frag, <, 1, %jd); 402 FCHK(fs->fs_frag, >, MAXFRAG, %jd); 403 FCHK(fs->fs_bsize, <, MINBSIZE, %jd); 404 FCHK(fs->fs_bsize, >, MAXBSIZE, %jd); 405 FCHK(fs->fs_bsize, <, roundup(sizeof(struct fs), DEV_BSIZE), 406 %jd); 407 FCHK(fs->fs_fsize, <, sectorsize, %jd); 408 FCHK(fs->fs_fsize * fs->fs_frag, !=, fs->fs_bsize, %jd); 409 FCHK(powerof2(fs->fs_fsize), ==, 0, %jd); 410 FCHK(fs->fs_sbsize, >, SBLOCKSIZE, %jd); 411 FCHK(fs->fs_sbsize, <, (signed)sizeof(struct fs), %jd); 412 FCHK(fs->fs_sbsize % sectorsize, !=, 0, %jd); 413 FCHK(fs->fs_fpg, <, 3 * fs->fs_frag, %jd); 414 FCHK(fs->fs_ncg, <, 1, %jd); 415 FCHK(fs->fs_fsbtodb, !=, ILOG2(fs->fs_fsize / sectorsize), %jd); 416 FCHK(fs->fs_old_cgoffset, <, 0, %jd); 417 FCHK2(fs->fs_old_cgoffset, >, 0, ~fs->fs_old_cgmask, <, 0, %jd); 418 FCHK(fs->fs_old_cgoffset * (~fs->fs_old_cgmask), >, fs->fs_fpg, 419 %jd); 420 FCHK(fs->fs_sblkno, !=, roundup( 421 howmany(fs->fs_sblockloc + SBLOCKSIZE, fs->fs_fsize), 422 fs->fs_frag), %jd); 423 FCHK(CGSIZE(fs), >, fs->fs_bsize, %jd); 424 /* Only need to validate these if reading in csum data */ 425 if ((flags & UFS_NOCSUM) != 0) 426 return (error); 427 FCHK((uint64_t)fs->fs_ipg * fs->fs_ncg, >, 428 (((int64_t)(1)) << 32) - INOPB(fs), %jd); 429 FCHK(fs->fs_cstotal.cs_nifree, <, 0, %jd); 430 FCHK(fs->fs_cstotal.cs_nifree, >, 431 (uint64_t)fs->fs_ipg * fs->fs_ncg, %jd); 432 FCHK(fs->fs_cstotal.cs_ndir, >, 433 ((uint64_t)fs->fs_ipg * fs->fs_ncg) - 434 fs->fs_cstotal.cs_nifree, %jd); 435 FCHK(fs->fs_size, <, 8 * fs->fs_frag, %jd); 436 FCHK(fs->fs_size, <=, ((int64_t)fs->fs_ncg - 1) * fs->fs_fpg, 437 %jd); 438 FCHK(fs->fs_size, >, (int64_t)fs->fs_ncg * fs->fs_fpg, %jd); 439 FCHK(fs->fs_csaddr, <, 0, %jd); 440 FCHK(fs->fs_cssize, !=, 441 fragroundup(fs, fs->fs_ncg * sizeof(struct csum)), %jd); 442 FCHK(fs->fs_csaddr + howmany(fs->fs_cssize, fs->fs_fsize), >, 443 fs->fs_size, %jd); 444 FCHK(fs->fs_csaddr, <, cgdmin(fs, dtog(fs, fs->fs_csaddr)), 445 %jd); 446 FCHK(dtog(fs, fs->fs_csaddr + howmany(fs->fs_cssize, 447 fs->fs_fsize)), >, dtog(fs, fs->fs_csaddr), %jd); 448 return (error); 449 } 450 if (fs->fs_magic == FS_UFS2_MAGIC) { 451 if ((flags & UFS_ALTSBLK) == 0) 452 FCHK2(fs->fs_sblockactualloc, !=, SBLOCK_UFS2, 453 fs->fs_sblockactualloc, !=, 0, %jd); 454 FCHK(fs->fs_sblockloc, !=, SBLOCK_UFS2, %#jx); 455 FCHK(fs->fs_maxsymlinklen, !=, ((UFS_NDADDR + UFS_NIADDR) * 456 sizeof(ufs2_daddr_t)), %jd); 457 FCHK(fs->fs_nindir, !=, fs->fs_bsize / sizeof(ufs2_daddr_t), 458 %jd); 459 FCHK(fs->fs_inopb, !=, 460 fs->fs_bsize / sizeof(struct ufs2_dinode), %jd); 461 } else if (fs->fs_magic == FS_UFS1_MAGIC) { 462 if ((flags & UFS_ALTSBLK) == 0) 463 FCHK(fs->fs_sblockactualloc, >, SBLOCK_UFS1, %jd); 464 FCHK(fs->fs_sblockloc, <, 0, %jd); 465 FCHK(fs->fs_sblockloc, >, SBLOCK_UFS1, %jd); 466 FCHK(fs->fs_nindir, !=, fs->fs_bsize / sizeof(ufs1_daddr_t), 467 %jd); 468 FCHK(fs->fs_inopb, !=, 469 fs->fs_bsize / sizeof(struct ufs1_dinode), %jd); 470 FCHK(fs->fs_maxsymlinklen, !=, ((UFS_NDADDR + UFS_NIADDR) * 471 sizeof(ufs1_daddr_t)), %jd); 472 WCHK(fs->fs_old_inodefmt, !=, FS_44INODEFMT, %jd); 473 WCHK(fs->fs_old_rotdelay, !=, 0, %jd); 474 WCHK(fs->fs_old_rps, !=, 60, %jd); 475 WCHK(fs->fs_old_nspf, !=, fs->fs_fsize / sectorsize, %jd); 476 FCHK(fs->fs_old_cpg, !=, 1, %jd); 477 WCHK(fs->fs_old_interleave, !=, 1, %jd); 478 WCHK(fs->fs_old_trackskew, !=, 0, %jd); 479 WCHK(fs->fs_old_cpc, !=, 0, %jd); 480 WCHK(fs->fs_old_postblformat, !=, 1, %jd); 481 FCHK(fs->fs_old_nrpos, !=, 1, %jd); 482 WCHK(fs->fs_old_spc, !=, fs->fs_fpg * fs->fs_old_nspf, %jd); 483 WCHK(fs->fs_old_nsect, !=, fs->fs_old_spc, %jd); 484 WCHK(fs->fs_old_npsect, !=, fs->fs_old_spc, %jd); 485 FCHK(fs->fs_old_ncyl, !=, fs->fs_ncg, %jd); 486 } else { 487 /* Bad magic number, so assume not a superblock */ 488 return (ENOENT); 489 } 490 FCHK(fs->fs_bsize, <, MINBSIZE, %jd); 491 FCHK(fs->fs_bsize, >, MAXBSIZE, %jd); 492 FCHK(fs->fs_bsize, <, roundup(sizeof(struct fs), DEV_BSIZE), %jd); 493 FCHK(powerof2(fs->fs_bsize), ==, 0, %jd); 494 FCHK(fs->fs_frag, <, 1, %jd); 495 FCHK(fs->fs_frag, >, MAXFRAG, %jd); 496 FCHK(fs->fs_frag, !=, numfrags(fs, fs->fs_bsize), %jd); 497 FCHK(fs->fs_fsize, <, sectorsize, %jd); 498 FCHK(fs->fs_fsize * fs->fs_frag, !=, fs->fs_bsize, %jd); 499 FCHK(powerof2(fs->fs_fsize), ==, 0, %jd); 500 FCHK(fs->fs_fpg, <, 3 * fs->fs_frag, %jd); 501 FCHK(fs->fs_ncg, <, 1, %jd); 502 FCHK(fs->fs_ipg, <, fs->fs_inopb, %jd); 503 FCHK((uint64_t)fs->fs_ipg * fs->fs_ncg, >, 504 (((int64_t)(1)) << 32) - INOPB(fs), %jd); 505 FCHK(fs->fs_cstotal.cs_nifree, <, 0, %jd); 506 FCHK(fs->fs_cstotal.cs_nifree, >, (uint64_t)fs->fs_ipg * fs->fs_ncg, 507 %jd); 508 FCHK(fs->fs_cstotal.cs_ndir, <, 0, %jd); 509 FCHK(fs->fs_cstotal.cs_ndir, >, 510 ((uint64_t)fs->fs_ipg * fs->fs_ncg) - fs->fs_cstotal.cs_nifree, 511 %jd); 512 FCHK(fs->fs_sbsize, >, SBLOCKSIZE, %jd); 513 FCHK(fs->fs_sbsize, <, (signed)sizeof(struct fs), %jd); 514 /* fix for misconfigured filesystems */ 515 if (fs->fs_maxbsize == 0) 516 fs->fs_maxbsize = fs->fs_bsize; 517 FCHK(fs->fs_maxbsize, <, fs->fs_bsize, %jd); 518 FCHK(powerof2(fs->fs_maxbsize), ==, 0, %jd); 519 FCHK(fs->fs_maxbsize, >, FS_MAXCONTIG * fs->fs_bsize, %jd); 520 FCHK(fs->fs_bmask, !=, ~(fs->fs_bsize - 1), %#jx); 521 FCHK(fs->fs_fmask, !=, ~(fs->fs_fsize - 1), %#jx); 522 FCHK(fs->fs_qbmask, !=, ~fs->fs_bmask, %#jx); 523 FCHK(fs->fs_qfmask, !=, ~fs->fs_fmask, %#jx); 524 FCHK(fs->fs_bshift, !=, ILOG2(fs->fs_bsize), %jd); 525 FCHK(fs->fs_fshift, !=, ILOG2(fs->fs_fsize), %jd); 526 FCHK(fs->fs_fragshift, !=, ILOG2(fs->fs_frag), %jd); 527 FCHK(fs->fs_fsbtodb, !=, ILOG2(fs->fs_fsize / sectorsize), %jd); 528 FCHK(fs->fs_old_cgoffset, <, 0, %jd); 529 FCHK2(fs->fs_old_cgoffset, >, 0, ~fs->fs_old_cgmask, <, 0, %jd); 530 FCHK(fs->fs_old_cgoffset * (~fs->fs_old_cgmask), >, fs->fs_fpg, %jd); 531 FCHK(CGSIZE(fs), >, fs->fs_bsize, %jd); 532 /* 533 * If anything has failed up to this point, it is usafe to proceed 534 * as checks below may divide by zero or make other fatal calculations. 535 * So if we have any errors at this point, give up. 536 */ 537 if (error) 538 return (error); 539 FCHK(fs->fs_sbsize % sectorsize, !=, 0, %jd); 540 FCHK(fs->fs_ipg % fs->fs_inopb, !=, 0, %jd); 541 FCHK(fs->fs_sblkno, !=, roundup( 542 howmany(fs->fs_sblockloc + SBLOCKSIZE, fs->fs_fsize), 543 fs->fs_frag), %jd); 544 FCHK(fs->fs_cblkno, !=, fs->fs_sblkno + 545 roundup(howmany(SBLOCKSIZE, fs->fs_fsize), fs->fs_frag), %jd); 546 FCHK(fs->fs_iblkno, !=, fs->fs_cblkno + fs->fs_frag, %jd); 547 FCHK(fs->fs_dblkno, !=, fs->fs_iblkno + fs->fs_ipg / INOPF(fs), %jd); 548 FCHK(fs->fs_cgsize, >, fs->fs_bsize, %jd); 549 FCHK(fs->fs_cgsize, <, fs->fs_fsize, %jd); 550 FCHK(fs->fs_cgsize % fs->fs_fsize, !=, 0, %jd); 551 /* 552 * This test is valid, however older versions of growfs failed 553 * to correctly update fs_dsize so will fail this test. Thus we 554 * exclude it from the requirements. 555 */ 556 #ifdef notdef 557 WCHK(fs->fs_dsize, !=, fs->fs_size - fs->fs_sblkno - 558 fs->fs_ncg * (fs->fs_dblkno - fs->fs_sblkno) - 559 howmany(fs->fs_cssize, fs->fs_fsize), %jd); 560 #endif 561 WCHK(fs->fs_metaspace, <, 0, %jd); 562 WCHK(fs->fs_metaspace, >, fs->fs_fpg / 2, %jd); 563 WCHK(fs->fs_minfree, >, 99, %jd%%); 564 maxfilesize = fs->fs_bsize * UFS_NDADDR - 1; 565 for (sizepb = fs->fs_bsize, i = 0; i < UFS_NIADDR; i++) { 566 sizepb *= NINDIR(fs); 567 maxfilesize += sizepb; 568 } 569 WCHK(fs->fs_maxfilesize, !=, maxfilesize, %jd); 570 /* 571 * These values have a tight interaction with each other that 572 * makes it hard to tightly bound them. So we can only check 573 * that they are within a broader possible range. 574 * 575 * The size cannot always be accurately determined, but ensure 576 * that it is consistent with the number of cylinder groups (fs_ncg) 577 * and the number of fragments per cylinder group (fs_fpg). Ensure 578 * that the summary information size is correct and that it starts 579 * and ends in the data area of the same cylinder group. 580 */ 581 FCHK(fs->fs_size, <, 8 * fs->fs_frag, %jd); 582 FCHK(fs->fs_size, <=, ((int64_t)fs->fs_ncg - 1) * fs->fs_fpg, %jd); 583 FCHK(fs->fs_size, >, (int64_t)fs->fs_ncg * fs->fs_fpg, %jd); 584 /* 585 * If we are not requested to read in the csum data stop here 586 * as the correctness of the remaining values is only important 587 * to bound the space needed to be allocated to hold the csum data. 588 */ 589 if ((flags & UFS_NOCSUM) != 0) 590 return (error); 591 FCHK(fs->fs_csaddr, <, 0, %jd); 592 FCHK(fs->fs_cssize, !=, 593 fragroundup(fs, fs->fs_ncg * sizeof(struct csum)), %jd); 594 FCHK(fs->fs_csaddr + howmany(fs->fs_cssize, fs->fs_fsize), >, 595 fs->fs_size, %jd); 596 FCHK(fs->fs_csaddr, <, cgdmin(fs, dtog(fs, fs->fs_csaddr)), %jd); 597 FCHK(dtog(fs, fs->fs_csaddr + howmany(fs->fs_cssize, fs->fs_fsize)), >, 598 dtog(fs, fs->fs_csaddr), %jd); 599 /* 600 * With file system clustering it is possible to allocate 601 * many contiguous blocks. The kernel variable maxphys defines 602 * the maximum transfer size permitted by the controller and/or 603 * buffering. The fs_maxcontig parameter controls the maximum 604 * number of blocks that the filesystem will read or write 605 * in a single transfer. It is calculated when the filesystem 606 * is created as maxphys / fs_bsize. The loader uses a maxphys 607 * of 128K even when running on a system that supports larger 608 * values. If the filesystem was built on a system that supports 609 * a larger maxphys (1M is typical) it will have configured 610 * fs_maxcontig for that larger system. So we bound the upper 611 * allowable limit for fs_maxconfig to be able to at least 612 * work with a 1M maxphys on the smallest block size filesystem: 613 * 1M / 4096 == 256. There is no harm in allowing the mounting of 614 * filesystems that make larger than maxphys I/O requests because 615 * those (mostly 32-bit machines) can (very slowly) handle I/O 616 * requests that exceed maxphys. 617 */ 618 WCHK(fs->fs_maxcontig, <, 0, %jd); 619 WCHK(fs->fs_maxcontig, >, MAX(256, maxphys / fs->fs_bsize), %jd); 620 FCHK2(fs->fs_maxcontig, ==, 0, fs->fs_contigsumsize, !=, 0, %jd); 621 FCHK2(fs->fs_maxcontig, >, 1, fs->fs_contigsumsize, !=, 622 MIN(fs->fs_maxcontig, FS_MAXCONTIG), %jd); 623 return (error); 624 } 625 626 /* 627 * Make an extensive search to find a superblock. If the superblock 628 * in the standard place cannot be used, try looking for one of the 629 * backup superblocks. 630 * 631 * Flags are made up of the following or'ed together options: 632 * 633 * UFS_NOMSG indicates that superblock inconsistency error messages 634 * should not be printed. 635 * 636 * UFS_NOCSUM causes only the superblock itself to be returned, but does 637 * not read in any auxillary data structures like the cylinder group 638 * summary information. 639 */ 640 int 641 ffs_sbsearch(void *devfd, struct fs **fsp, int reqflags, 642 struct malloc_type *filltype, 643 int (*readfunc)(void *devfd, off_t loc, void **bufp, int size)) 644 { 645 struct fsrecovery *fsr; 646 struct fs *protofs; 647 void *fsrbuf; 648 char *cp; 649 long nocsum, flags, msg, cg; 650 off_t sblk, secsize; 651 int error; 652 653 msg = (reqflags & UFS_NOMSG) == 0; 654 nocsum = reqflags & UFS_NOCSUM; 655 /* 656 * Try normal superblock read and return it if it works. 657 * 658 * Suppress messages if it fails until we find out if 659 * failure can be avoided. 660 */ 661 flags = UFS_NOMSG | nocsum; 662 error = ffs_sbget(devfd, fsp, UFS_STDSB, flags, filltype, readfunc); 663 /* 664 * If successful or endian error, no need to try further. 665 */ 666 if (error == 0 || error == EILSEQ) { 667 if (msg && error == EILSEQ) 668 printf("UFS superblock failed due to endian mismatch " 669 "between machine and filesystem\n"); 670 return (error); 671 } 672 /* 673 * First try: ignoring hash failures. 674 */ 675 flags |= UFS_NOHASHFAIL; 676 if (msg) 677 flags &= ~UFS_NOMSG; 678 if (ffs_sbget(devfd, fsp, UFS_STDSB, flags, filltype, readfunc) == 0) 679 return (0); 680 /* 681 * Next up is to check if fields of the superblock that are 682 * needed to find backup superblocks are usable. 683 */ 684 if (msg) 685 printf("Attempted recovery for standard superblock: failed\n"); 686 flags = UFS_FSRONLY | UFS_NOHASHFAIL | UFS_NOCSUM | UFS_NOMSG; 687 if (ffs_sbget(devfd, &protofs, UFS_STDSB, flags, filltype, 688 readfunc) == 0) { 689 if (msg) 690 printf("Attempt extraction of recovery data from " 691 "standard superblock.\n"); 692 } else { 693 /* 694 * Final desperation is to see if alternate superblock 695 * parameters have been saved in the boot area. 696 */ 697 if (msg) 698 printf("Attempted extraction of recovery data from " 699 "standard superblock: failed\nAttempt to find " 700 "boot zone recovery data.\n"); 701 /* 702 * Look to see if recovery information has been saved. 703 * If so we can generate a prototype superblock based 704 * on that information. 705 * 706 * We need fragments-per-group, number of cylinder groups, 707 * location of the superblock within the cylinder group, and 708 * the conversion from filesystem fragments to disk blocks. 709 * 710 * When building a UFS2 filesystem, newfs(8) stores these 711 * details at the end of the boot block area at the start 712 * of the filesystem partition. If they have been overwritten 713 * by a boot block, we fail. But usually they are there 714 * and we can use them. 715 * 716 * We could ask the underlying device for its sector size, 717 * but some devices lie. So we just try a plausible range. 718 */ 719 error = ENOENT; 720 fsrbuf = NULL; 721 for (secsize = dbtob(1); secsize <= SBLOCKSIZE; secsize *= 2) 722 if ((error = (*readfunc)(devfd, (SBLOCK_UFS2 - secsize), 723 &fsrbuf, secsize)) == 0) 724 break; 725 if (error != 0) 726 goto trynowarn; 727 cp = fsrbuf; /* type change to keep compiler happy */ 728 fsr = (struct fsrecovery *)&cp[secsize - sizeof *fsr]; 729 if (fsr->fsr_magic != FS_UFS2_MAGIC || 730 (protofs = UFS_MALLOC(SBLOCKSIZE, filltype, M_NOWAIT)) 731 == NULL) { 732 UFS_FREE(fsrbuf, filltype); 733 goto trynowarn; 734 } 735 memset(protofs, 0, sizeof(struct fs)); 736 protofs->fs_fpg = fsr->fsr_fpg; 737 protofs->fs_fsbtodb = fsr->fsr_fsbtodb; 738 protofs->fs_sblkno = fsr->fsr_sblkno; 739 protofs->fs_magic = fsr->fsr_magic; 740 protofs->fs_ncg = fsr->fsr_ncg; 741 UFS_FREE(fsrbuf, filltype); 742 } 743 /* 744 * Scan looking for alternative superblocks. 745 */ 746 flags = nocsum; 747 if (!msg) 748 flags |= UFS_NOMSG; 749 for (cg = 0; cg < protofs->fs_ncg; cg++) { 750 sblk = fsbtodb(protofs, cgsblock(protofs, cg)); 751 if (msg) 752 printf("Try cg %ld at sblock loc %jd\n", cg, 753 (intmax_t)sblk); 754 if (ffs_sbget(devfd, fsp, dbtob(sblk), flags, filltype, 755 readfunc) == 0) { 756 if (msg) 757 printf("Succeeded with alternate superblock " 758 "at %jd\n", (intmax_t)sblk); 759 UFS_FREE(protofs, filltype); 760 return (0); 761 } 762 } 763 UFS_FREE(protofs, filltype); 764 /* 765 * Our alternate superblock strategies failed. Our last ditch effort 766 * is to see if the standard superblock has only non-critical errors. 767 */ 768 trynowarn: 769 flags = UFS_NOWARNFAIL | UFS_NOMSG | nocsum; 770 if (msg) { 771 printf("Finding an alternate superblock failed.\nCheck for " 772 "only non-critical errors in standard superblock\n"); 773 flags &= ~UFS_NOMSG; 774 } 775 if (ffs_sbget(devfd, fsp, UFS_STDSB, flags, filltype, readfunc) != 0) { 776 if (msg) 777 printf("Failed, superblock has critical errors\n"); 778 return (ENOENT); 779 } 780 if (msg) 781 printf("Success, using standard superblock with " 782 "non-critical errors.\n"); 783 return (0); 784 } 785 786 /* 787 * Write a superblock to the devfd device from the memory pointed to by fs. 788 * Write out the superblock summary information if it is present. 789 * 790 * If the write is successful, zero is returned. Otherwise one of the 791 * following error values is returned: 792 * EIO: failed to write superblock. 793 * EIO: failed to write superblock summary information. 794 */ 795 int 796 ffs_sbput(void *devfd, struct fs *fs, off_t loc, 797 int (*writefunc)(void *devfd, off_t loc, void *buf, int size)) 798 { 799 int i, error, blks, size; 800 uint8_t *space; 801 802 /* 803 * If there is summary information, write it first, so if there 804 * is an error, the superblock will not be marked as clean. 805 */ 806 if (fs->fs_si != NULL && fs->fs_csp != NULL) { 807 blks = howmany(fs->fs_cssize, fs->fs_fsize); 808 space = (uint8_t *)fs->fs_csp; 809 for (i = 0; i < blks; i += fs->fs_frag) { 810 size = fs->fs_bsize; 811 if (i + fs->fs_frag > blks) 812 size = (blks - i) * fs->fs_fsize; 813 if ((error = (*writefunc)(devfd, 814 dbtob(fsbtodb(fs, fs->fs_csaddr + i)), 815 space, size)) != 0) 816 return (error); 817 space += size; 818 } 819 } 820 fs->fs_fmod = 0; 821 #ifndef _KERNEL 822 { 823 struct fs_summary_info *fs_si; 824 825 fs->fs_time = time(NULL); 826 /* Clear the pointers for the duration of writing. */ 827 fs_si = fs->fs_si; 828 fs->fs_si = NULL; 829 fs->fs_ckhash = ffs_calc_sbhash(fs); 830 error = (*writefunc)(devfd, loc, fs, fs->fs_sbsize); 831 fs->fs_si = fs_si; 832 } 833 #else /* _KERNEL */ 834 fs->fs_time = time_second; 835 fs->fs_ckhash = ffs_calc_sbhash(fs); 836 error = (*writefunc)(devfd, loc, fs, fs->fs_sbsize); 837 #endif /* _KERNEL */ 838 return (error); 839 } 840 841 /* 842 * Calculate the check-hash for a superblock. 843 */ 844 uint32_t 845 ffs_calc_sbhash(struct fs *fs) 846 { 847 uint32_t ckhash, save_ckhash; 848 849 /* 850 * A filesystem that was using a superblock ckhash may be moved 851 * to an older kernel that does not support ckhashes. The 852 * older kernel will clear the FS_METACKHASH flag indicating 853 * that it does not update hashes. When the disk is moved back 854 * to a kernel capable of ckhashes it disables them on mount: 855 * 856 * if ((fs->fs_flags & FS_METACKHASH) == 0) 857 * fs->fs_metackhash = 0; 858 * 859 * This leaves (fs->fs_metackhash & CK_SUPERBLOCK) == 0) with an 860 * old stale value in the fs->fs_ckhash field. Thus the need to 861 * just accept what is there. 862 */ 863 if ((fs->fs_metackhash & CK_SUPERBLOCK) == 0) 864 return (fs->fs_ckhash); 865 866 save_ckhash = fs->fs_ckhash; 867 fs->fs_ckhash = 0; 868 /* 869 * If newly read from disk, the caller is responsible for 870 * verifying that fs->fs_sbsize <= SBLOCKSIZE. 871 */ 872 ckhash = calculate_crc32c(~0L, (void *)fs, fs->fs_sbsize); 873 fs->fs_ckhash = save_ckhash; 874 return (ckhash); 875 } 876 877 /* 878 * Update the frsum fields to reflect addition or deletion 879 * of some frags. 880 */ 881 void 882 ffs_fragacct(struct fs *fs, int fragmap, int32_t fraglist[], int cnt) 883 { 884 int inblk; 885 int field, subfield; 886 int siz, pos; 887 888 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 889 fragmap <<= 1; 890 for (siz = 1; siz < fs->fs_frag; siz++) { 891 if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0) 892 continue; 893 field = around[siz]; 894 subfield = inside[siz]; 895 for (pos = siz; pos <= fs->fs_frag; pos++) { 896 if ((fragmap & field) == subfield) { 897 fraglist[siz] += cnt; 898 pos += siz; 899 field <<= siz; 900 subfield <<= siz; 901 } 902 field <<= 1; 903 subfield <<= 1; 904 } 905 } 906 } 907 908 /* 909 * block operations 910 * 911 * check if a block is available 912 */ 913 int 914 ffs_isblock(struct fs *fs, unsigned char *cp, ufs1_daddr_t h) 915 { 916 unsigned char mask; 917 918 switch ((int)fs->fs_frag) { 919 case 8: 920 return (cp[h] == 0xff); 921 case 4: 922 mask = 0x0f << ((h & 0x1) << 2); 923 return ((cp[h >> 1] & mask) == mask); 924 case 2: 925 mask = 0x03 << ((h & 0x3) << 1); 926 return ((cp[h >> 2] & mask) == mask); 927 case 1: 928 mask = 0x01 << (h & 0x7); 929 return ((cp[h >> 3] & mask) == mask); 930 default: 931 #ifdef _KERNEL 932 panic("ffs_isblock"); 933 #endif 934 break; 935 } 936 return (0); 937 } 938 939 /* 940 * check if a block is free 941 */ 942 int 943 ffs_isfreeblock(struct fs *fs, uint8_t *cp, ufs1_daddr_t h) 944 { 945 946 switch ((int)fs->fs_frag) { 947 case 8: 948 return (cp[h] == 0); 949 case 4: 950 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 951 case 2: 952 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 953 case 1: 954 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 955 default: 956 #ifdef _KERNEL 957 panic("ffs_isfreeblock"); 958 #endif 959 break; 960 } 961 return (0); 962 } 963 964 /* 965 * take a block out of the map 966 */ 967 void 968 ffs_clrblock(struct fs *fs, uint8_t *cp, ufs1_daddr_t h) 969 { 970 971 switch ((int)fs->fs_frag) { 972 case 8: 973 cp[h] = 0; 974 return; 975 case 4: 976 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 977 return; 978 case 2: 979 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 980 return; 981 case 1: 982 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 983 return; 984 default: 985 #ifdef _KERNEL 986 panic("ffs_clrblock"); 987 #endif 988 break; 989 } 990 } 991 992 /* 993 * put a block into the map 994 */ 995 void 996 ffs_setblock(struct fs *fs, unsigned char *cp, ufs1_daddr_t h) 997 { 998 999 switch ((int)fs->fs_frag) { 1000 case 8: 1001 cp[h] = 0xff; 1002 return; 1003 case 4: 1004 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 1005 return; 1006 case 2: 1007 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 1008 return; 1009 case 1: 1010 cp[h >> 3] |= (0x01 << (h & 0x7)); 1011 return; 1012 default: 1013 #ifdef _KERNEL 1014 panic("ffs_setblock"); 1015 #endif 1016 break; 1017 } 1018 } 1019 1020 /* 1021 * Update the cluster map because of an allocation or free. 1022 * 1023 * Cnt == 1 means free; cnt == -1 means allocating. 1024 */ 1025 void 1026 ffs_clusteracct(struct fs *fs, struct cg *cgp, ufs1_daddr_t blkno, int cnt) 1027 { 1028 int32_t *sump; 1029 int32_t *lp; 1030 uint8_t *freemapp, *mapp; 1031 int i, start, end, forw, back, map; 1032 uint64_t bit; 1033 1034 if (fs->fs_contigsumsize <= 0) 1035 return; 1036 freemapp = cg_clustersfree(cgp); 1037 sump = cg_clustersum(cgp); 1038 /* 1039 * Allocate or clear the actual block. 1040 */ 1041 if (cnt > 0) 1042 setbit(freemapp, blkno); 1043 else 1044 clrbit(freemapp, blkno); 1045 /* 1046 * Find the size of the cluster going forward. 1047 */ 1048 start = blkno + 1; 1049 end = start + fs->fs_contigsumsize; 1050 if (end >= cgp->cg_nclusterblks) 1051 end = cgp->cg_nclusterblks; 1052 mapp = &freemapp[start / NBBY]; 1053 map = *mapp++; 1054 bit = 1U << (start % NBBY); 1055 for (i = start; i < end; i++) { 1056 if ((map & bit) == 0) 1057 break; 1058 if ((i & (NBBY - 1)) != (NBBY - 1)) { 1059 bit <<= 1; 1060 } else { 1061 map = *mapp++; 1062 bit = 1; 1063 } 1064 } 1065 forw = i - start; 1066 /* 1067 * Find the size of the cluster going backward. 1068 */ 1069 start = blkno - 1; 1070 end = start - fs->fs_contigsumsize; 1071 if (end < 0) 1072 end = -1; 1073 mapp = &freemapp[start / NBBY]; 1074 map = *mapp--; 1075 bit = 1U << (start % NBBY); 1076 for (i = start; i > end; i--) { 1077 if ((map & bit) == 0) 1078 break; 1079 if ((i & (NBBY - 1)) != 0) { 1080 bit >>= 1; 1081 } else { 1082 map = *mapp--; 1083 bit = 1U << (NBBY - 1); 1084 } 1085 } 1086 back = start - i; 1087 /* 1088 * Account for old cluster and the possibly new forward and 1089 * back clusters. 1090 */ 1091 i = back + forw + 1; 1092 if (i > fs->fs_contigsumsize) 1093 i = fs->fs_contigsumsize; 1094 sump[i] += cnt; 1095 if (back > 0) 1096 sump[back] -= cnt; 1097 if (forw > 0) 1098 sump[forw] -= cnt; 1099 /* 1100 * Update cluster summary information. 1101 */ 1102 lp = &sump[fs->fs_contigsumsize]; 1103 for (i = fs->fs_contigsumsize; i > 0; i--) 1104 if (*lp-- > 0) 1105 break; 1106 fs->fs_maxcluster[cgp->cg_cgx] = i; 1107 } 1108