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 * @(#)ffs_subr.c 8.5 (Berkeley) 3/21/95 32 */ 33 34 #include <sys/cdefs.h> 35 #include <sys/param.h> 36 #include <sys/endian.h> 37 #include <sys/limits.h> 38 39 #ifndef _KERNEL 40 #include <stdio.h> 41 #include <string.h> 42 #include <stdlib.h> 43 #include <time.h> 44 #include <sys/errno.h> 45 #include <ufs/ufs/dinode.h> 46 #include <ufs/ffs/fs.h> 47 48 uint32_t calculate_crc32c(uint32_t, const void *, size_t); 49 uint32_t ffs_calc_sbhash(struct fs *); 50 struct malloc_type; 51 #define UFS_MALLOC(size, type, flags) malloc(size) 52 #define UFS_FREE(ptr, type) free(ptr) 53 #define maxphys MAXPHYS 54 55 #else /* _KERNEL */ 56 #include <sys/systm.h> 57 #include <sys/gsb_crc32.h> 58 #include <sys/lock.h> 59 #include <sys/malloc.h> 60 #include <sys/mount.h> 61 #include <sys/vnode.h> 62 #include <sys/bio.h> 63 #include <sys/buf.h> 64 #include <sys/ucred.h> 65 66 #include <ufs/ufs/quota.h> 67 #include <ufs/ufs/inode.h> 68 #include <ufs/ufs/extattr.h> 69 #include <ufs/ufs/ufsmount.h> 70 #include <ufs/ufs/ufs_extern.h> 71 #include <ufs/ffs/ffs_extern.h> 72 #include <ufs/ffs/fs.h> 73 74 #define UFS_MALLOC(size, type, flags) malloc(size, type, flags) 75 #define UFS_FREE(ptr, type) free(ptr, type) 76 77 #endif /* _KERNEL */ 78 79 /* 80 * Verify an inode check-hash. 81 */ 82 int 83 ffs_verify_dinode_ckhash(struct fs *fs, struct ufs2_dinode *dip) 84 { 85 uint32_t ckhash, save_ckhash; 86 87 /* 88 * Return success if unallocated or we are not doing inode check-hash. 89 */ 90 if (dip->di_mode == 0 || (fs->fs_metackhash & CK_INODE) == 0) 91 return (0); 92 /* 93 * Exclude di_ckhash from the crc32 calculation, e.g., always use 94 * a check-hash value of zero when calculating the check-hash. 95 */ 96 save_ckhash = dip->di_ckhash; 97 dip->di_ckhash = 0; 98 ckhash = calculate_crc32c(~0L, (void *)dip, sizeof(*dip)); 99 dip->di_ckhash = save_ckhash; 100 if (save_ckhash == ckhash) 101 return (0); 102 return (EINVAL); 103 } 104 105 /* 106 * Update an inode check-hash. 107 */ 108 void 109 ffs_update_dinode_ckhash(struct fs *fs, struct ufs2_dinode *dip) 110 { 111 112 if (dip->di_mode == 0 || (fs->fs_metackhash & CK_INODE) == 0) 113 return; 114 /* 115 * Exclude old di_ckhash from the crc32 calculation, e.g., always use 116 * a check-hash value of zero when calculating the new check-hash. 117 */ 118 dip->di_ckhash = 0; 119 dip->di_ckhash = calculate_crc32c(~0L, (void *)dip, sizeof(*dip)); 120 } 121 122 /* 123 * These are the low-level functions that actually read and write 124 * the superblock and its associated data. 125 */ 126 static off_t sblock_try[] = SBLOCKSEARCH; 127 static int readsuper(void *, struct fs **, off_t, int, 128 int (*)(void *, off_t, void **, int)); 129 static int validate_sblock(struct fs *, int); 130 131 /* 132 * Read a superblock from the devfd device. 133 * 134 * If an alternate superblock is specified, it is read. Otherwise the 135 * set of locations given in the SBLOCKSEARCH list is searched for a 136 * superblock. Memory is allocated for the superblock by the readfunc and 137 * is returned. If filltype is non-NULL, additional memory is allocated 138 * of type filltype and filled in with the superblock summary information. 139 * All memory is freed when any error is returned. 140 * 141 * If a superblock is found, zero is returned. Otherwise one of the 142 * following error values is returned: 143 * EIO: non-existent or truncated superblock. 144 * EIO: error reading summary information. 145 * ENOENT: no usable known superblock found. 146 * EILSEQ: filesystem with wrong byte order found. 147 * ENOMEM: failed to allocate space for the superblock. 148 * EINVAL: The previous newfs operation on this volume did not complete. 149 * The administrator must complete newfs before using this volume. 150 */ 151 int 152 ffs_sbget(void *devfd, struct fs **fsp, off_t sblock, int flags, 153 struct malloc_type *filltype, 154 int (*readfunc)(void *devfd, off_t loc, void **bufp, int size)) 155 { 156 struct fs *fs; 157 struct fs_summary_info *fs_si; 158 int i, error; 159 uint64_t size, blks; 160 uint8_t *space; 161 int32_t *lp; 162 char *buf; 163 164 fs = NULL; 165 *fsp = NULL; 166 if (sblock != UFS_STDSB) { 167 if ((error = readsuper(devfd, &fs, sblock, 168 flags | UFS_ALTSBLK, readfunc)) != 0) { 169 if (fs != NULL) 170 UFS_FREE(fs, filltype); 171 return (error); 172 } 173 } else { 174 for (i = 0; sblock_try[i] != -1; i++) { 175 if ((error = readsuper(devfd, &fs, sblock_try[i], 176 flags, readfunc)) == 0) { 177 if ((flags & UFS_NOCSUM) != 0) { 178 *fsp = fs; 179 return (0); 180 } 181 break; 182 } 183 if (fs != NULL) { 184 UFS_FREE(fs, filltype); 185 fs = NULL; 186 } 187 if (error == ENOENT) 188 continue; 189 return (error); 190 } 191 if (sblock_try[i] == -1) 192 return (ENOENT); 193 } 194 /* 195 * Read in the superblock summary information. 196 */ 197 size = fs->fs_cssize; 198 blks = howmany(size, fs->fs_fsize); 199 if (fs->fs_contigsumsize > 0) 200 size += fs->fs_ncg * sizeof(int32_t); 201 size += fs->fs_ncg * sizeof(uint8_t); 202 if ((fs_si = UFS_MALLOC(sizeof(*fs_si), filltype, M_NOWAIT)) == NULL) { 203 UFS_FREE(fs, filltype); 204 return (ENOMEM); 205 } 206 bzero(fs_si, sizeof(*fs_si)); 207 fs->fs_si = fs_si; 208 if ((space = UFS_MALLOC(size, filltype, M_NOWAIT)) == NULL) { 209 UFS_FREE(fs->fs_si, filltype); 210 UFS_FREE(fs, filltype); 211 return (ENOMEM); 212 } 213 fs->fs_csp = (struct csum *)space; 214 for (i = 0; i < blks; i += fs->fs_frag) { 215 size = fs->fs_bsize; 216 if (i + fs->fs_frag > blks) 217 size = (blks - i) * fs->fs_fsize; 218 buf = NULL; 219 error = (*readfunc)(devfd, 220 dbtob(fsbtodb(fs, fs->fs_csaddr + i)), (void **)&buf, size); 221 if (error) { 222 if (buf != NULL) 223 UFS_FREE(buf, filltype); 224 UFS_FREE(fs->fs_csp, filltype); 225 UFS_FREE(fs->fs_si, filltype); 226 UFS_FREE(fs, filltype); 227 return (error); 228 } 229 memcpy(space, buf, size); 230 UFS_FREE(buf, filltype); 231 space += size; 232 } 233 if (fs->fs_contigsumsize > 0) { 234 fs->fs_maxcluster = lp = (int32_t *)space; 235 for (i = 0; i < fs->fs_ncg; i++) 236 *lp++ = fs->fs_contigsumsize; 237 space = (uint8_t *)lp; 238 } 239 size = fs->fs_ncg * sizeof(uint8_t); 240 fs->fs_contigdirs = (uint8_t *)space; 241 bzero(fs->fs_contigdirs, size); 242 *fsp = fs; 243 return (0); 244 } 245 246 /* 247 * Try to read a superblock from the location specified by sblockloc. 248 * Return zero on success or an errno on failure. 249 */ 250 static int 251 readsuper(void *devfd, struct fs **fsp, off_t sblockloc, int flags, 252 int (*readfunc)(void *devfd, off_t loc, void **bufp, int size)) 253 { 254 struct fs *fs; 255 int error, res; 256 uint32_t ckhash; 257 258 error = (*readfunc)(devfd, sblockloc, (void **)fsp, SBLOCKSIZE); 259 if (error != 0) 260 return (error); 261 fs = *fsp; 262 if (fs->fs_magic == FS_BAD_MAGIC) 263 return (EINVAL); 264 /* 265 * For UFS1 with a 65536 block size, the first backup superblock 266 * is at the same location as the UFS2 superblock. Since SBLOCK_UFS2 267 * is the first location checked, the first backup is the superblock 268 * that will be accessed. Here we fail the lookup so that we can 269 * retry with the correct location for the UFS1 superblock. 270 */ 271 if (fs->fs_magic == FS_UFS1_MAGIC && (flags & UFS_ALTSBLK) == 0 && 272 fs->fs_bsize == SBLOCK_UFS2 && sblockloc == SBLOCK_UFS2) 273 return (ENOENT); 274 if ((error = validate_sblock(fs, flags)) > 0) 275 return (error); 276 /* 277 * If the filesystem has been run on a kernel without 278 * metadata check hashes, disable them. 279 */ 280 if ((fs->fs_flags & FS_METACKHASH) == 0) 281 fs->fs_metackhash = 0; 282 /* 283 * Clear any check-hashes that are not maintained 284 * by this kernel. Also clear any unsupported flags. 285 */ 286 fs->fs_metackhash &= CK_SUPPORTED; 287 fs->fs_flags &= FS_SUPPORTED; 288 if (fs->fs_ckhash != (ckhash = ffs_calc_sbhash(fs))) { 289 if ((flags & (UFS_NOMSG | UFS_NOHASHFAIL)) == 290 (UFS_NOMSG | UFS_NOHASHFAIL)) 291 return (0); 292 if ((flags & UFS_NOMSG) != 0) 293 return (EINTEGRITY); 294 #ifdef _KERNEL 295 res = uprintf("Superblock check-hash failed: recorded " 296 "check-hash 0x%x != computed check-hash 0x%x%s\n", 297 fs->fs_ckhash, ckhash, 298 (flags & UFS_NOHASHFAIL) != 0 ? " (Ignored)" : ""); 299 #else 300 res = 0; 301 #endif 302 /* 303 * Print check-hash failure if no controlling terminal 304 * in kernel or always if in user-mode (libufs). 305 */ 306 if (res == 0) 307 printf("Superblock check-hash failed: recorded " 308 "check-hash 0x%x != computed check-hash " 309 "0x%x%s\n", fs->fs_ckhash, ckhash, 310 (flags & UFS_NOHASHFAIL) ? " (Ignored)" : ""); 311 if ((flags & UFS_NOHASHFAIL) != 0) 312 return (0); 313 return (EINTEGRITY); 314 } 315 /* Have to set for old filesystems that predate this field */ 316 fs->fs_sblockactualloc = sblockloc; 317 /* Not yet any summary information */ 318 fs->fs_si = NULL; 319 return (0); 320 } 321 322 /* 323 * Verify the filesystem values. 324 */ 325 #define ILOG2(num) (fls(num) - 1) 326 #ifdef STANDALONE_SMALL 327 #define MPRINT(...) do { } while (0) 328 #else 329 #define MPRINT(...) if (prtmsg) printf(__VA_ARGS__) 330 #endif 331 #define FCHK(lhs, op, rhs, fmt) \ 332 if (lhs op rhs) { \ 333 MPRINT("UFS%d superblock failed: %s (" #fmt ") %s %s (" \ 334 #fmt ")\n", fs->fs_magic == FS_UFS1_MAGIC ? 1 : 2, \ 335 #lhs, (intmax_t)lhs, #op, #rhs, (intmax_t)rhs); \ 336 if (error < 0) \ 337 return (ENOENT); \ 338 if (error == 0) \ 339 error = ENOENT; \ 340 } 341 #define WCHK(lhs, op, rhs, fmt) \ 342 if (lhs op rhs) { \ 343 MPRINT("UFS%d superblock failed: %s (" #fmt ") %s %s (" \ 344 #fmt ")%s\n", fs->fs_magic == FS_UFS1_MAGIC ? 1 : 2,\ 345 #lhs, (intmax_t)lhs, #op, #rhs, (intmax_t)rhs, wmsg);\ 346 if (error == 0) \ 347 error = warnerr; \ 348 if (warnerr == 0) \ 349 lhs = rhs; \ 350 } 351 #define FCHK2(lhs1, op1, rhs1, lhs2, op2, rhs2, fmt) \ 352 if (lhs1 op1 rhs1 && lhs2 op2 rhs2) { \ 353 MPRINT("UFS%d superblock failed: %s (" #fmt ") %s %s (" \ 354 #fmt ") && %s (" #fmt ") %s %s (" #fmt ")\n", \ 355 fs->fs_magic == FS_UFS1_MAGIC ? 1 : 2, #lhs1, \ 356 (intmax_t)lhs1, #op1, #rhs1, (intmax_t)rhs1, #lhs2, \ 357 (intmax_t)lhs2, #op2, #rhs2, (intmax_t)rhs2); \ 358 if (error < 0) \ 359 return (ENOENT); \ 360 if (error == 0) \ 361 error = ENOENT; \ 362 } 363 364 static int 365 validate_sblock(struct fs *fs, int flags) 366 { 367 uint64_t i, sectorsize; 368 uint64_t maxfilesize, sizepb; 369 int error, prtmsg, warnerr; 370 char *wmsg; 371 372 error = 0; 373 sectorsize = dbtob(1); 374 prtmsg = ((flags & UFS_NOMSG) == 0); 375 warnerr = (flags & UFS_NOWARNFAIL) == UFS_NOWARNFAIL ? 0 : ENOENT; 376 wmsg = warnerr ? "" : " (Ignored)"; 377 /* 378 * Check for endian mismatch between machine and filesystem. 379 */ 380 if (((fs->fs_magic != FS_UFS2_MAGIC) && 381 (bswap32(fs->fs_magic) == FS_UFS2_MAGIC)) || 382 ((fs->fs_magic != FS_UFS1_MAGIC) && 383 (bswap32(fs->fs_magic) == FS_UFS1_MAGIC))) { 384 MPRINT("UFS superblock failed due to endian mismatch " 385 "between machine and filesystem\n"); 386 return(EILSEQ); 387 } 388 /* 389 * If just validating for recovery, then do just the minimal 390 * checks needed for the superblock fields needed to find 391 * alternate superblocks. 392 */ 393 if ((flags & UFS_FSRONLY) == UFS_FSRONLY && 394 (fs->fs_magic == FS_UFS1_MAGIC || fs->fs_magic == FS_UFS2_MAGIC)) { 395 error = -1; /* fail on first error */ 396 if (fs->fs_magic == FS_UFS2_MAGIC) { 397 FCHK(fs->fs_sblockloc, !=, SBLOCK_UFS2, %#jx); 398 } else if (fs->fs_magic == FS_UFS1_MAGIC) { 399 FCHK(fs->fs_sblockloc, <, 0, %jd); 400 FCHK(fs->fs_sblockloc, >, SBLOCK_UFS1, %jd); 401 FCHK(fs->fs_old_ncyl, !=, fs->fs_ncg, %jd); 402 } 403 FCHK(fs->fs_frag, <, 1, %jd); 404 FCHK(fs->fs_frag, >, MAXFRAG, %jd); 405 FCHK(fs->fs_bsize, <, MINBSIZE, %jd); 406 FCHK(fs->fs_bsize, >, MAXBSIZE, %jd); 407 FCHK(fs->fs_bsize, <, roundup(sizeof(struct fs), DEV_BSIZE), 408 %jd); 409 FCHK(fs->fs_fsize, <, sectorsize, %jd); 410 FCHK(fs->fs_fsize * fs->fs_frag, !=, fs->fs_bsize, %jd); 411 FCHK(powerof2(fs->fs_fsize), ==, 0, %jd); 412 FCHK(fs->fs_sbsize, >, SBLOCKSIZE, %jd); 413 FCHK(fs->fs_sbsize, <, (signed)sizeof(struct fs), %jd); 414 FCHK(fs->fs_sbsize % sectorsize, !=, 0, %jd); 415 FCHK(fs->fs_fpg, <, 3 * fs->fs_frag, %jd); 416 FCHK(fs->fs_ncg, <, 1, %jd); 417 FCHK(fs->fs_fsbtodb, !=, ILOG2(fs->fs_fsize / sectorsize), %jd); 418 FCHK(fs->fs_old_cgoffset, <, 0, %jd); 419 FCHK2(fs->fs_old_cgoffset, >, 0, ~fs->fs_old_cgmask, <, 0, %jd); 420 FCHK(fs->fs_old_cgoffset * (~fs->fs_old_cgmask), >, fs->fs_fpg, 421 %jd); 422 FCHK(fs->fs_sblkno, !=, roundup( 423 howmany(fs->fs_sblockloc + SBLOCKSIZE, fs->fs_fsize), 424 fs->fs_frag), %jd); 425 FCHK(CGSIZE(fs), >, fs->fs_bsize, %jd); 426 /* Only need to validate these if reading in csum data */ 427 if ((flags & UFS_NOCSUM) != 0) 428 return (error); 429 FCHK((uint64_t)fs->fs_ipg * fs->fs_ncg, >, 430 (((int64_t)(1)) << 32) - INOPB(fs), %jd); 431 FCHK(fs->fs_cstotal.cs_nifree, <, 0, %jd); 432 FCHK(fs->fs_cstotal.cs_nifree, >, 433 (uint64_t)fs->fs_ipg * fs->fs_ncg, %jd); 434 FCHK(fs->fs_cstotal.cs_ndir, >, 435 ((uint64_t)fs->fs_ipg * fs->fs_ncg) - 436 fs->fs_cstotal.cs_nifree, %jd); 437 FCHK(fs->fs_size, <, 8 * fs->fs_frag, %jd); 438 FCHK(fs->fs_size, <=, ((int64_t)fs->fs_ncg - 1) * fs->fs_fpg, 439 %jd); 440 FCHK(fs->fs_size, >, (int64_t)fs->fs_ncg * fs->fs_fpg, %jd); 441 FCHK(fs->fs_csaddr, <, 0, %jd); 442 FCHK(fs->fs_cssize, !=, 443 fragroundup(fs, fs->fs_ncg * sizeof(struct csum)), %jd); 444 FCHK(fs->fs_csaddr + howmany(fs->fs_cssize, fs->fs_fsize), >, 445 fs->fs_size, %jd); 446 FCHK(fs->fs_csaddr, <, cgdmin(fs, dtog(fs, fs->fs_csaddr)), 447 %jd); 448 FCHK(dtog(fs, fs->fs_csaddr + howmany(fs->fs_cssize, 449 fs->fs_fsize)), >, dtog(fs, fs->fs_csaddr), %jd); 450 return (error); 451 } 452 if (fs->fs_magic == FS_UFS2_MAGIC) { 453 if ((flags & UFS_ALTSBLK) == 0) 454 FCHK2(fs->fs_sblockactualloc, !=, SBLOCK_UFS2, 455 fs->fs_sblockactualloc, !=, 0, %jd); 456 FCHK(fs->fs_sblockloc, !=, SBLOCK_UFS2, %#jx); 457 FCHK(fs->fs_maxsymlinklen, !=, ((UFS_NDADDR + UFS_NIADDR) * 458 sizeof(ufs2_daddr_t)), %jd); 459 FCHK(fs->fs_nindir, !=, fs->fs_bsize / sizeof(ufs2_daddr_t), 460 %jd); 461 FCHK(fs->fs_inopb, !=, 462 fs->fs_bsize / sizeof(struct ufs2_dinode), %jd); 463 } else if (fs->fs_magic == FS_UFS1_MAGIC) { 464 if ((flags & UFS_ALTSBLK) == 0) 465 FCHK(fs->fs_sblockactualloc, >, SBLOCK_UFS1, %jd); 466 FCHK(fs->fs_sblockloc, <, 0, %jd); 467 FCHK(fs->fs_sblockloc, >, SBLOCK_UFS1, %jd); 468 FCHK(fs->fs_nindir, !=, fs->fs_bsize / sizeof(ufs1_daddr_t), 469 %jd); 470 FCHK(fs->fs_inopb, !=, 471 fs->fs_bsize / sizeof(struct ufs1_dinode), %jd); 472 FCHK(fs->fs_maxsymlinklen, !=, ((UFS_NDADDR + UFS_NIADDR) * 473 sizeof(ufs1_daddr_t)), %jd); 474 WCHK(fs->fs_old_inodefmt, !=, FS_44INODEFMT, %jd); 475 WCHK(fs->fs_old_rotdelay, !=, 0, %jd); 476 WCHK(fs->fs_old_rps, !=, 60, %jd); 477 WCHK(fs->fs_old_nspf, !=, fs->fs_fsize / sectorsize, %jd); 478 FCHK(fs->fs_old_cpg, !=, 1, %jd); 479 WCHK(fs->fs_old_interleave, !=, 1, %jd); 480 WCHK(fs->fs_old_trackskew, !=, 0, %jd); 481 WCHK(fs->fs_old_cpc, !=, 0, %jd); 482 WCHK(fs->fs_old_postblformat, !=, 1, %jd); 483 FCHK(fs->fs_old_nrpos, !=, 1, %jd); 484 WCHK(fs->fs_old_spc, !=, fs->fs_fpg * fs->fs_old_nspf, %jd); 485 WCHK(fs->fs_old_nsect, !=, fs->fs_old_spc, %jd); 486 WCHK(fs->fs_old_npsect, !=, fs->fs_old_spc, %jd); 487 FCHK(fs->fs_old_ncyl, !=, fs->fs_ncg, %jd); 488 } else { 489 /* Bad magic number, so assume not a superblock */ 490 return (ENOENT); 491 } 492 FCHK(fs->fs_bsize, <, MINBSIZE, %jd); 493 FCHK(fs->fs_bsize, >, MAXBSIZE, %jd); 494 FCHK(fs->fs_bsize, <, roundup(sizeof(struct fs), DEV_BSIZE), %jd); 495 FCHK(powerof2(fs->fs_bsize), ==, 0, %jd); 496 FCHK(fs->fs_frag, <, 1, %jd); 497 FCHK(fs->fs_frag, >, MAXFRAG, %jd); 498 FCHK(fs->fs_frag, !=, numfrags(fs, fs->fs_bsize), %jd); 499 FCHK(fs->fs_fsize, <, sectorsize, %jd); 500 FCHK(fs->fs_fsize * fs->fs_frag, !=, fs->fs_bsize, %jd); 501 FCHK(powerof2(fs->fs_fsize), ==, 0, %jd); 502 FCHK(fs->fs_fpg, <, 3 * fs->fs_frag, %jd); 503 FCHK(fs->fs_ncg, <, 1, %jd); 504 FCHK(fs->fs_ipg, <, fs->fs_inopb, %jd); 505 FCHK((uint64_t)fs->fs_ipg * fs->fs_ncg, >, 506 (((int64_t)(1)) << 32) - INOPB(fs), %jd); 507 FCHK(fs->fs_cstotal.cs_nifree, <, 0, %jd); 508 FCHK(fs->fs_cstotal.cs_nifree, >, (uint64_t)fs->fs_ipg * fs->fs_ncg, 509 %jd); 510 FCHK(fs->fs_cstotal.cs_ndir, <, 0, %jd); 511 FCHK(fs->fs_cstotal.cs_ndir, >, 512 ((uint64_t)fs->fs_ipg * fs->fs_ncg) - fs->fs_cstotal.cs_nifree, 513 %jd); 514 FCHK(fs->fs_sbsize, >, SBLOCKSIZE, %jd); 515 FCHK(fs->fs_sbsize, <, (signed)sizeof(struct fs), %jd); 516 /* fix for misconfigured filesystems */ 517 if (fs->fs_maxbsize == 0) 518 fs->fs_maxbsize = fs->fs_bsize; 519 FCHK(fs->fs_maxbsize, <, fs->fs_bsize, %jd); 520 FCHK(powerof2(fs->fs_maxbsize), ==, 0, %jd); 521 FCHK(fs->fs_maxbsize, >, FS_MAXCONTIG * fs->fs_bsize, %jd); 522 FCHK(fs->fs_bmask, !=, ~(fs->fs_bsize - 1), %#jx); 523 FCHK(fs->fs_fmask, !=, ~(fs->fs_fsize - 1), %#jx); 524 FCHK(fs->fs_qbmask, !=, ~fs->fs_bmask, %#jx); 525 FCHK(fs->fs_qfmask, !=, ~fs->fs_fmask, %#jx); 526 FCHK(fs->fs_bshift, !=, ILOG2(fs->fs_bsize), %jd); 527 FCHK(fs->fs_fshift, !=, ILOG2(fs->fs_fsize), %jd); 528 FCHK(fs->fs_fragshift, !=, ILOG2(fs->fs_frag), %jd); 529 FCHK(fs->fs_fsbtodb, !=, ILOG2(fs->fs_fsize / sectorsize), %jd); 530 FCHK(fs->fs_old_cgoffset, <, 0, %jd); 531 FCHK2(fs->fs_old_cgoffset, >, 0, ~fs->fs_old_cgmask, <, 0, %jd); 532 FCHK(fs->fs_old_cgoffset * (~fs->fs_old_cgmask), >, fs->fs_fpg, %jd); 533 FCHK(CGSIZE(fs), >, fs->fs_bsize, %jd); 534 /* 535 * If anything has failed up to this point, it is usafe to proceed 536 * as checks below may divide by zero or make other fatal calculations. 537 * So if we have any errors at this point, give up. 538 */ 539 if (error) 540 return (error); 541 FCHK(fs->fs_sbsize % sectorsize, !=, 0, %jd); 542 FCHK(fs->fs_ipg % fs->fs_inopb, !=, 0, %jd); 543 FCHK(fs->fs_sblkno, !=, roundup( 544 howmany(fs->fs_sblockloc + SBLOCKSIZE, fs->fs_fsize), 545 fs->fs_frag), %jd); 546 FCHK(fs->fs_cblkno, !=, fs->fs_sblkno + 547 roundup(howmany(SBLOCKSIZE, fs->fs_fsize), fs->fs_frag), %jd); 548 FCHK(fs->fs_iblkno, !=, fs->fs_cblkno + fs->fs_frag, %jd); 549 FCHK(fs->fs_dblkno, !=, fs->fs_iblkno + fs->fs_ipg / INOPF(fs), %jd); 550 FCHK(fs->fs_cgsize, >, fs->fs_bsize, %jd); 551 FCHK(fs->fs_cgsize, <, fs->fs_fsize, %jd); 552 FCHK(fs->fs_cgsize % fs->fs_fsize, !=, 0, %jd); 553 /* 554 * This test is valid, however older versions of growfs failed 555 * to correctly update fs_dsize so will fail this test. Thus we 556 * exclude it from the requirements. 557 */ 558 #ifdef notdef 559 WCHK(fs->fs_dsize, !=, fs->fs_size - fs->fs_sblkno - 560 fs->fs_ncg * (fs->fs_dblkno - fs->fs_sblkno) - 561 howmany(fs->fs_cssize, fs->fs_fsize), %jd); 562 #endif 563 WCHK(fs->fs_metaspace, <, 0, %jd); 564 WCHK(fs->fs_metaspace, >, fs->fs_fpg / 2, %jd); 565 WCHK(fs->fs_minfree, >, 99, %jd%%); 566 maxfilesize = fs->fs_bsize * UFS_NDADDR - 1; 567 for (sizepb = fs->fs_bsize, i = 0; i < UFS_NIADDR; i++) { 568 sizepb *= NINDIR(fs); 569 maxfilesize += sizepb; 570 } 571 WCHK(fs->fs_maxfilesize, !=, maxfilesize, %jd); 572 /* 573 * These values have a tight interaction with each other that 574 * makes it hard to tightly bound them. So we can only check 575 * that they are within a broader possible range. 576 * 577 * The size cannot always be accurately determined, but ensure 578 * that it is consistent with the number of cylinder groups (fs_ncg) 579 * and the number of fragments per cylinder group (fs_fpg). Ensure 580 * that the summary information size is correct and that it starts 581 * and ends in the data area of the same cylinder group. 582 */ 583 FCHK(fs->fs_size, <, 8 * fs->fs_frag, %jd); 584 FCHK(fs->fs_size, <=, ((int64_t)fs->fs_ncg - 1) * fs->fs_fpg, %jd); 585 FCHK(fs->fs_size, >, (int64_t)fs->fs_ncg * fs->fs_fpg, %jd); 586 /* 587 * If we are not requested to read in the csum data stop here 588 * as the correctness of the remaining values is only important 589 * to bound the space needed to be allocated to hold the csum data. 590 */ 591 if ((flags & UFS_NOCSUM) != 0) 592 return (error); 593 FCHK(fs->fs_csaddr, <, 0, %jd); 594 FCHK(fs->fs_cssize, !=, 595 fragroundup(fs, fs->fs_ncg * sizeof(struct csum)), %jd); 596 FCHK(fs->fs_csaddr + howmany(fs->fs_cssize, fs->fs_fsize), >, 597 fs->fs_size, %jd); 598 FCHK(fs->fs_csaddr, <, cgdmin(fs, dtog(fs, fs->fs_csaddr)), %jd); 599 FCHK(dtog(fs, fs->fs_csaddr + howmany(fs->fs_cssize, fs->fs_fsize)), >, 600 dtog(fs, fs->fs_csaddr), %jd); 601 /* 602 * With file system clustering it is possible to allocate 603 * many contiguous blocks. The kernel variable maxphys defines 604 * the maximum transfer size permitted by the controller and/or 605 * buffering. The fs_maxcontig parameter controls the maximum 606 * number of blocks that the filesystem will read or write 607 * in a single transfer. It is calculated when the filesystem 608 * is created as maxphys / fs_bsize. The loader uses a maxphys 609 * of 128K even when running on a system that supports larger 610 * values. If the filesystem was built on a system that supports 611 * a larger maxphys (1M is typical) it will have configured 612 * fs_maxcontig for that larger system. So we bound the upper 613 * allowable limit for fs_maxconfig to be able to at least 614 * work with a 1M maxphys on the smallest block size filesystem: 615 * 1M / 4096 == 256. There is no harm in allowing the mounting of 616 * filesystems that make larger than maxphys I/O requests because 617 * those (mostly 32-bit machines) can (very slowly) handle I/O 618 * requests that exceed maxphys. 619 */ 620 WCHK(fs->fs_maxcontig, <, 0, %jd); 621 WCHK(fs->fs_maxcontig, >, MAX(256, maxphys / fs->fs_bsize), %jd); 622 FCHK2(fs->fs_maxcontig, ==, 0, fs->fs_contigsumsize, !=, 0, %jd); 623 FCHK2(fs->fs_maxcontig, >, 1, fs->fs_contigsumsize, !=, 624 MIN(fs->fs_maxcontig, FS_MAXCONTIG), %jd); 625 return (error); 626 } 627 628 /* 629 * Make an extensive search to find a superblock. If the superblock 630 * in the standard place cannot be used, try looking for one of the 631 * backup superblocks. 632 * 633 * Flags are made up of the following or'ed together options: 634 * 635 * UFS_NOMSG indicates that superblock inconsistency error messages 636 * should not be printed. 637 * 638 * UFS_NOCSUM causes only the superblock itself to be returned, but does 639 * not read in any auxillary data structures like the cylinder group 640 * summary information. 641 */ 642 int 643 ffs_sbsearch(void *devfd, struct fs **fsp, int reqflags, 644 struct malloc_type *filltype, 645 int (*readfunc)(void *devfd, off_t loc, void **bufp, int size)) 646 { 647 struct fsrecovery *fsr; 648 struct fs *protofs; 649 void *fsrbuf; 650 char *cp; 651 long nocsum, flags, msg, cg; 652 off_t sblk, secsize; 653 int error; 654 655 msg = (reqflags & UFS_NOMSG) == 0; 656 nocsum = reqflags & UFS_NOCSUM; 657 /* 658 * Try normal superblock read and return it if it works. 659 * 660 * Suppress messages if it fails until we find out if 661 * failure can be avoided. 662 */ 663 flags = UFS_NOMSG | nocsum; 664 error = ffs_sbget(devfd, fsp, UFS_STDSB, flags, filltype, readfunc); 665 /* 666 * If successful or endian error, no need to try further. 667 */ 668 if (error == 0 || error == EILSEQ) { 669 if (msg && error == EILSEQ) 670 printf("UFS superblock failed due to endian mismatch " 671 "between machine and filesystem\n"); 672 return (error); 673 } 674 /* 675 * First try: ignoring hash failures. 676 */ 677 flags |= UFS_NOHASHFAIL; 678 if (msg) 679 flags &= ~UFS_NOMSG; 680 if (ffs_sbget(devfd, fsp, UFS_STDSB, flags, filltype, readfunc) == 0) 681 return (0); 682 /* 683 * Next up is to check if fields of the superblock that are 684 * needed to find backup superblocks are usable. 685 */ 686 if (msg) 687 printf("Attempted recovery for standard superblock: failed\n"); 688 flags = UFS_FSRONLY | UFS_NOHASHFAIL | UFS_NOCSUM | UFS_NOMSG; 689 if (ffs_sbget(devfd, &protofs, UFS_STDSB, flags, filltype, 690 readfunc) == 0) { 691 if (msg) 692 printf("Attempt extraction of recovery data from " 693 "standard superblock.\n"); 694 } else { 695 /* 696 * Final desperation is to see if alternate superblock 697 * parameters have been saved in the boot area. 698 */ 699 if (msg) 700 printf("Attempted extraction of recovery data from " 701 "standard superblock: failed\nAttempt to find " 702 "boot zone recovery data.\n"); 703 /* 704 * Look to see if recovery information has been saved. 705 * If so we can generate a prototype superblock based 706 * on that information. 707 * 708 * We need fragments-per-group, number of cylinder groups, 709 * location of the superblock within the cylinder group, and 710 * the conversion from filesystem fragments to disk blocks. 711 * 712 * When building a UFS2 filesystem, newfs(8) stores these 713 * details at the end of the boot block area at the start 714 * of the filesystem partition. If they have been overwritten 715 * by a boot block, we fail. But usually they are there 716 * and we can use them. 717 * 718 * We could ask the underlying device for its sector size, 719 * but some devices lie. So we just try a plausible range. 720 */ 721 error = ENOENT; 722 fsrbuf = NULL; 723 for (secsize = dbtob(1); secsize <= SBLOCKSIZE; secsize *= 2) 724 if ((error = (*readfunc)(devfd, (SBLOCK_UFS2 - secsize), 725 &fsrbuf, secsize)) == 0) 726 break; 727 if (error != 0) 728 goto trynowarn; 729 cp = fsrbuf; /* type change to keep compiler happy */ 730 fsr = (struct fsrecovery *)&cp[secsize - sizeof *fsr]; 731 if (fsr->fsr_magic != FS_UFS2_MAGIC || 732 (protofs = UFS_MALLOC(SBLOCKSIZE, filltype, M_NOWAIT)) 733 == NULL) { 734 UFS_FREE(fsrbuf, filltype); 735 goto trynowarn; 736 } 737 memset(protofs, 0, sizeof(struct fs)); 738 protofs->fs_fpg = fsr->fsr_fpg; 739 protofs->fs_fsbtodb = fsr->fsr_fsbtodb; 740 protofs->fs_sblkno = fsr->fsr_sblkno; 741 protofs->fs_magic = fsr->fsr_magic; 742 protofs->fs_ncg = fsr->fsr_ncg; 743 UFS_FREE(fsrbuf, filltype); 744 } 745 /* 746 * Scan looking for alternative superblocks. 747 */ 748 flags = nocsum; 749 if (!msg) 750 flags |= UFS_NOMSG; 751 for (cg = 0; cg < protofs->fs_ncg; cg++) { 752 sblk = fsbtodb(protofs, cgsblock(protofs, cg)); 753 if (msg) 754 printf("Try cg %ld at sblock loc %jd\n", cg, 755 (intmax_t)sblk); 756 if (ffs_sbget(devfd, fsp, dbtob(sblk), flags, filltype, 757 readfunc) == 0) { 758 if (msg) 759 printf("Succeeded with alternate superblock " 760 "at %jd\n", (intmax_t)sblk); 761 UFS_FREE(protofs, filltype); 762 return (0); 763 } 764 } 765 UFS_FREE(protofs, filltype); 766 /* 767 * Our alternate superblock strategies failed. Our last ditch effort 768 * is to see if the standard superblock has only non-critical errors. 769 */ 770 trynowarn: 771 flags = UFS_NOWARNFAIL | UFS_NOMSG | nocsum; 772 if (msg) { 773 printf("Finding an alternate superblock failed.\nCheck for " 774 "only non-critical errors in standard superblock\n"); 775 flags &= ~UFS_NOMSG; 776 } 777 if (ffs_sbget(devfd, fsp, UFS_STDSB, flags, filltype, readfunc) != 0) { 778 if (msg) 779 printf("Failed, superblock has critical errors\n"); 780 return (ENOENT); 781 } 782 if (msg) 783 printf("Success, using standard superblock with " 784 "non-critical errors.\n"); 785 return (0); 786 } 787 788 /* 789 * Write a superblock to the devfd device from the memory pointed to by fs. 790 * Write out the superblock summary information if it is present. 791 * 792 * If the write is successful, zero is returned. Otherwise one of the 793 * following error values is returned: 794 * EIO: failed to write superblock. 795 * EIO: failed to write superblock summary information. 796 */ 797 int 798 ffs_sbput(void *devfd, struct fs *fs, off_t loc, 799 int (*writefunc)(void *devfd, off_t loc, void *buf, int size)) 800 { 801 int i, error, blks, size; 802 uint8_t *space; 803 804 /* 805 * If there is summary information, write it first, so if there 806 * is an error, the superblock will not be marked as clean. 807 */ 808 if (fs->fs_si != NULL && fs->fs_csp != NULL) { 809 blks = howmany(fs->fs_cssize, fs->fs_fsize); 810 space = (uint8_t *)fs->fs_csp; 811 for (i = 0; i < blks; i += fs->fs_frag) { 812 size = fs->fs_bsize; 813 if (i + fs->fs_frag > blks) 814 size = (blks - i) * fs->fs_fsize; 815 if ((error = (*writefunc)(devfd, 816 dbtob(fsbtodb(fs, fs->fs_csaddr + i)), 817 space, size)) != 0) 818 return (error); 819 space += size; 820 } 821 } 822 fs->fs_fmod = 0; 823 #ifndef _KERNEL 824 { 825 struct fs_summary_info *fs_si; 826 827 fs->fs_time = time(NULL); 828 /* Clear the pointers for the duration of writing. */ 829 fs_si = fs->fs_si; 830 fs->fs_si = NULL; 831 fs->fs_ckhash = ffs_calc_sbhash(fs); 832 error = (*writefunc)(devfd, loc, fs, fs->fs_sbsize); 833 fs->fs_si = fs_si; 834 } 835 #else /* _KERNEL */ 836 fs->fs_time = time_second; 837 fs->fs_ckhash = ffs_calc_sbhash(fs); 838 error = (*writefunc)(devfd, loc, fs, fs->fs_sbsize); 839 #endif /* _KERNEL */ 840 return (error); 841 } 842 843 /* 844 * Calculate the check-hash for a superblock. 845 */ 846 uint32_t 847 ffs_calc_sbhash(struct fs *fs) 848 { 849 uint32_t ckhash, save_ckhash; 850 851 /* 852 * A filesystem that was using a superblock ckhash may be moved 853 * to an older kernel that does not support ckhashes. The 854 * older kernel will clear the FS_METACKHASH flag indicating 855 * that it does not update hashes. When the disk is moved back 856 * to a kernel capable of ckhashes it disables them on mount: 857 * 858 * if ((fs->fs_flags & FS_METACKHASH) == 0) 859 * fs->fs_metackhash = 0; 860 * 861 * This leaves (fs->fs_metackhash & CK_SUPERBLOCK) == 0) with an 862 * old stale value in the fs->fs_ckhash field. Thus the need to 863 * just accept what is there. 864 */ 865 if ((fs->fs_metackhash & CK_SUPERBLOCK) == 0) 866 return (fs->fs_ckhash); 867 868 save_ckhash = fs->fs_ckhash; 869 fs->fs_ckhash = 0; 870 /* 871 * If newly read from disk, the caller is responsible for 872 * verifying that fs->fs_sbsize <= SBLOCKSIZE. 873 */ 874 ckhash = calculate_crc32c(~0L, (void *)fs, fs->fs_sbsize); 875 fs->fs_ckhash = save_ckhash; 876 return (ckhash); 877 } 878 879 /* 880 * Update the frsum fields to reflect addition or deletion 881 * of some frags. 882 */ 883 void 884 ffs_fragacct(struct fs *fs, int fragmap, int32_t fraglist[], int cnt) 885 { 886 int inblk; 887 int field, subfield; 888 int siz, pos; 889 890 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 891 fragmap <<= 1; 892 for (siz = 1; siz < fs->fs_frag; siz++) { 893 if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0) 894 continue; 895 field = around[siz]; 896 subfield = inside[siz]; 897 for (pos = siz; pos <= fs->fs_frag; pos++) { 898 if ((fragmap & field) == subfield) { 899 fraglist[siz] += cnt; 900 pos += siz; 901 field <<= siz; 902 subfield <<= siz; 903 } 904 field <<= 1; 905 subfield <<= 1; 906 } 907 } 908 } 909 910 /* 911 * block operations 912 * 913 * check if a block is available 914 */ 915 int 916 ffs_isblock(struct fs *fs, unsigned char *cp, ufs1_daddr_t h) 917 { 918 unsigned char mask; 919 920 switch ((int)fs->fs_frag) { 921 case 8: 922 return (cp[h] == 0xff); 923 case 4: 924 mask = 0x0f << ((h & 0x1) << 2); 925 return ((cp[h >> 1] & mask) == mask); 926 case 2: 927 mask = 0x03 << ((h & 0x3) << 1); 928 return ((cp[h >> 2] & mask) == mask); 929 case 1: 930 mask = 0x01 << (h & 0x7); 931 return ((cp[h >> 3] & mask) == mask); 932 default: 933 #ifdef _KERNEL 934 panic("ffs_isblock"); 935 #endif 936 break; 937 } 938 return (0); 939 } 940 941 /* 942 * check if a block is free 943 */ 944 int 945 ffs_isfreeblock(struct fs *fs, uint8_t *cp, ufs1_daddr_t h) 946 { 947 948 switch ((int)fs->fs_frag) { 949 case 8: 950 return (cp[h] == 0); 951 case 4: 952 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 953 case 2: 954 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 955 case 1: 956 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 957 default: 958 #ifdef _KERNEL 959 panic("ffs_isfreeblock"); 960 #endif 961 break; 962 } 963 return (0); 964 } 965 966 /* 967 * take a block out of the map 968 */ 969 void 970 ffs_clrblock(struct fs *fs, uint8_t *cp, ufs1_daddr_t h) 971 { 972 973 switch ((int)fs->fs_frag) { 974 case 8: 975 cp[h] = 0; 976 return; 977 case 4: 978 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 979 return; 980 case 2: 981 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 982 return; 983 case 1: 984 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 985 return; 986 default: 987 #ifdef _KERNEL 988 panic("ffs_clrblock"); 989 #endif 990 break; 991 } 992 } 993 994 /* 995 * put a block into the map 996 */ 997 void 998 ffs_setblock(struct fs *fs, unsigned char *cp, ufs1_daddr_t h) 999 { 1000 1001 switch ((int)fs->fs_frag) { 1002 case 8: 1003 cp[h] = 0xff; 1004 return; 1005 case 4: 1006 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 1007 return; 1008 case 2: 1009 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 1010 return; 1011 case 1: 1012 cp[h >> 3] |= (0x01 << (h & 0x7)); 1013 return; 1014 default: 1015 #ifdef _KERNEL 1016 panic("ffs_setblock"); 1017 #endif 1018 break; 1019 } 1020 } 1021 1022 /* 1023 * Update the cluster map because of an allocation or free. 1024 * 1025 * Cnt == 1 means free; cnt == -1 means allocating. 1026 */ 1027 void 1028 ffs_clusteracct(struct fs *fs, struct cg *cgp, ufs1_daddr_t blkno, int cnt) 1029 { 1030 int32_t *sump; 1031 int32_t *lp; 1032 uint8_t *freemapp, *mapp; 1033 int i, start, end, forw, back, map; 1034 uint64_t bit; 1035 1036 if (fs->fs_contigsumsize <= 0) 1037 return; 1038 freemapp = cg_clustersfree(cgp); 1039 sump = cg_clustersum(cgp); 1040 /* 1041 * Allocate or clear the actual block. 1042 */ 1043 if (cnt > 0) 1044 setbit(freemapp, blkno); 1045 else 1046 clrbit(freemapp, blkno); 1047 /* 1048 * Find the size of the cluster going forward. 1049 */ 1050 start = blkno + 1; 1051 end = start + fs->fs_contigsumsize; 1052 if (end >= cgp->cg_nclusterblks) 1053 end = cgp->cg_nclusterblks; 1054 mapp = &freemapp[start / NBBY]; 1055 map = *mapp++; 1056 bit = 1U << (start % NBBY); 1057 for (i = start; i < end; i++) { 1058 if ((map & bit) == 0) 1059 break; 1060 if ((i & (NBBY - 1)) != (NBBY - 1)) { 1061 bit <<= 1; 1062 } else { 1063 map = *mapp++; 1064 bit = 1; 1065 } 1066 } 1067 forw = i - start; 1068 /* 1069 * Find the size of the cluster going backward. 1070 */ 1071 start = blkno - 1; 1072 end = start - fs->fs_contigsumsize; 1073 if (end < 0) 1074 end = -1; 1075 mapp = &freemapp[start / NBBY]; 1076 map = *mapp--; 1077 bit = 1U << (start % NBBY); 1078 for (i = start; i > end; i--) { 1079 if ((map & bit) == 0) 1080 break; 1081 if ((i & (NBBY - 1)) != 0) { 1082 bit >>= 1; 1083 } else { 1084 map = *mapp--; 1085 bit = 1U << (NBBY - 1); 1086 } 1087 } 1088 back = start - i; 1089 /* 1090 * Account for old cluster and the possibly new forward and 1091 * back clusters. 1092 */ 1093 i = back + forw + 1; 1094 if (i > fs->fs_contigsumsize) 1095 i = fs->fs_contigsumsize; 1096 sump[i] += cnt; 1097 if (back > 0) 1098 sump[back] -= cnt; 1099 if (forw > 0) 1100 sump[forw] -= cnt; 1101 /* 1102 * Update cluster summary information. 1103 */ 1104 lp = &sump[fs->fs_contigsumsize]; 1105 for (i = fs->fs_contigsumsize; i > 0; i--) 1106 if (*lp-- > 0) 1107 break; 1108 fs->fs_maxcluster[cgp->cg_cgx] = i; 1109 } 1110