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 __FBSDID("$FreeBSD$"); 36 37 #include <sys/param.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 UFS_TIME time(NULL) 54 /* 55 * Request standard superblock location in ffs_sbget 56 */ 57 #define STDSB -1 /* Fail if check-hash is bad */ 58 #define STDSB_NOHASHFAIL -2 /* Ignore check-hash failure */ 59 60 #else /* _KERNEL */ 61 #include <sys/systm.h> 62 #include <sys/gsb_crc32.h> 63 #include <sys/lock.h> 64 #include <sys/malloc.h> 65 #include <sys/mount.h> 66 #include <sys/vnode.h> 67 #include <sys/bio.h> 68 #include <sys/buf.h> 69 #include <sys/ucred.h> 70 71 #include <ufs/ufs/quota.h> 72 #include <ufs/ufs/inode.h> 73 #include <ufs/ufs/extattr.h> 74 #include <ufs/ufs/ufsmount.h> 75 #include <ufs/ufs/ufs_extern.h> 76 #include <ufs/ffs/ffs_extern.h> 77 #include <ufs/ffs/fs.h> 78 79 #define UFS_MALLOC(size, type, flags) malloc(size, type, flags) 80 #define UFS_FREE(ptr, type) free(ptr, type) 81 #define UFS_TIME time_second 82 83 /* 84 * Return buffer with the contents of block "offset" from the beginning of 85 * directory "ip". If "res" is non-zero, fill it in with a pointer to the 86 * remaining space in the directory. 87 */ 88 int 89 ffs_blkatoff(struct vnode *vp, off_t offset, char **res, struct buf **bpp) 90 { 91 struct inode *ip; 92 struct fs *fs; 93 struct buf *bp; 94 ufs_lbn_t lbn; 95 int bsize, error; 96 97 ip = VTOI(vp); 98 fs = ITOFS(ip); 99 lbn = lblkno(fs, offset); 100 bsize = blksize(fs, ip, lbn); 101 102 *bpp = NULL; 103 error = bread(vp, lbn, bsize, NOCRED, &bp); 104 if (error) { 105 brelse(bp); 106 return (error); 107 } 108 if (res) 109 *res = (char *)bp->b_data + blkoff(fs, offset); 110 *bpp = bp; 111 return (0); 112 } 113 114 /* 115 * Load up the contents of an inode and copy the appropriate pieces 116 * to the incore copy. 117 */ 118 int 119 ffs_load_inode(struct buf *bp, struct inode *ip, struct fs *fs, ino_t ino) 120 { 121 struct ufs1_dinode *dip1; 122 struct ufs2_dinode *dip2; 123 int error; 124 125 if (I_IS_UFS1(ip)) { 126 dip1 = ip->i_din1; 127 *dip1 = 128 *((struct ufs1_dinode *)bp->b_data + ino_to_fsbo(fs, ino)); 129 ip->i_mode = dip1->di_mode; 130 ip->i_nlink = dip1->di_nlink; 131 ip->i_effnlink = dip1->di_nlink; 132 ip->i_size = dip1->di_size; 133 ip->i_flags = dip1->di_flags; 134 ip->i_gen = dip1->di_gen; 135 ip->i_uid = dip1->di_uid; 136 ip->i_gid = dip1->di_gid; 137 return (0); 138 } 139 dip2 = ((struct ufs2_dinode *)bp->b_data + ino_to_fsbo(fs, ino)); 140 if ((error = ffs_verify_dinode_ckhash(fs, dip2)) != 0) { 141 printf("%s: inode %jd: check-hash failed\n", fs->fs_fsmnt, 142 (intmax_t)ino); 143 return (error); 144 } 145 *ip->i_din2 = *dip2; 146 dip2 = ip->i_din2; 147 ip->i_mode = dip2->di_mode; 148 ip->i_nlink = dip2->di_nlink; 149 ip->i_effnlink = dip2->di_nlink; 150 ip->i_size = dip2->di_size; 151 ip->i_flags = dip2->di_flags; 152 ip->i_gen = dip2->di_gen; 153 ip->i_uid = dip2->di_uid; 154 ip->i_gid = dip2->di_gid; 155 return (0); 156 } 157 158 /* 159 * Verify that a filesystem block number is a valid data block. 160 * This routine is only called on untrusted filesystems. 161 */ 162 int 163 ffs_check_blkno(struct mount *mp, ino_t inum, ufs2_daddr_t daddr, int blksize) 164 { 165 struct fs *fs; 166 struct ufsmount *ump; 167 ufs2_daddr_t end_daddr; 168 int cg, havemtx; 169 170 KASSERT((mp->mnt_flag & MNT_UNTRUSTED) != 0, 171 ("ffs_check_blkno called on a trusted file system")); 172 ump = VFSTOUFS(mp); 173 fs = ump->um_fs; 174 cg = dtog(fs, daddr); 175 end_daddr = daddr + numfrags(fs, blksize); 176 /* 177 * Verify that the block number is a valid data block. Also check 178 * that it does not point to an inode block or a superblock. Accept 179 * blocks that are unalloacted (0) or part of snapshot metadata 180 * (BLK_NOCOPY or BLK_SNAP). 181 * 182 * Thus, the block must be in a valid range for the filesystem and 183 * either in the space before a backup superblock (except the first 184 * cylinder group where that space is used by the bootstrap code) or 185 * after the inode blocks and before the end of the cylinder group. 186 */ 187 if ((uint64_t)daddr <= BLK_SNAP || 188 ((uint64_t)end_daddr <= fs->fs_size && 189 ((cg > 0 && end_daddr <= cgsblock(fs, cg)) || 190 (daddr >= cgdmin(fs, cg) && 191 end_daddr <= cgbase(fs, cg) + fs->fs_fpg)))) 192 return (0); 193 if ((havemtx = mtx_owned(UFS_MTX(ump))) == 0) 194 UFS_LOCK(ump); 195 if (ppsratecheck(&ump->um_last_integritymsg, 196 &ump->um_secs_integritymsg, 1)) { 197 UFS_UNLOCK(ump); 198 uprintf("\n%s: inode %jd, out-of-range indirect block " 199 "number %jd\n", mp->mnt_stat.f_mntonname, inum, daddr); 200 if (havemtx) 201 UFS_LOCK(ump); 202 } else if (!havemtx) 203 UFS_UNLOCK(ump); 204 return (EINTEGRITY); 205 } 206 #endif /* _KERNEL */ 207 208 /* 209 * Verify an inode check-hash. 210 */ 211 int 212 ffs_verify_dinode_ckhash(struct fs *fs, struct ufs2_dinode *dip) 213 { 214 uint32_t ckhash, save_ckhash; 215 216 /* 217 * Return success if unallocated or we are not doing inode check-hash. 218 */ 219 if (dip->di_mode == 0 || (fs->fs_metackhash & CK_INODE) == 0) 220 return (0); 221 /* 222 * Exclude di_ckhash from the crc32 calculation, e.g., always use 223 * a check-hash value of zero when calculating the check-hash. 224 */ 225 save_ckhash = dip->di_ckhash; 226 dip->di_ckhash = 0; 227 ckhash = calculate_crc32c(~0L, (void *)dip, sizeof(*dip)); 228 dip->di_ckhash = save_ckhash; 229 if (save_ckhash == ckhash) 230 return (0); 231 return (EINVAL); 232 } 233 234 /* 235 * Update an inode check-hash. 236 */ 237 void 238 ffs_update_dinode_ckhash(struct fs *fs, struct ufs2_dinode *dip) 239 { 240 241 if (dip->di_mode == 0 || (fs->fs_metackhash & CK_INODE) == 0) 242 return; 243 /* 244 * Exclude old di_ckhash from the crc32 calculation, e.g., always use 245 * a check-hash value of zero when calculating the new check-hash. 246 */ 247 dip->di_ckhash = 0; 248 dip->di_ckhash = calculate_crc32c(~0L, (void *)dip, sizeof(*dip)); 249 } 250 251 /* 252 * These are the low-level functions that actually read and write 253 * the superblock and its associated data. 254 */ 255 static off_t sblock_try[] = SBLOCKSEARCH; 256 static int readsuper(void *, struct fs **, off_t, int, int, 257 int (*)(void *, off_t, void **, int)); 258 259 /* 260 * Read a superblock from the devfd device. 261 * 262 * If an alternate superblock is specified, it is read. Otherwise the 263 * set of locations given in the SBLOCKSEARCH list is searched for a 264 * superblock. Memory is allocated for the superblock by the readfunc and 265 * is returned. If filltype is non-NULL, additional memory is allocated 266 * of type filltype and filled in with the superblock summary information. 267 * All memory is freed when any error is returned. 268 * 269 * If a superblock is found, zero is returned. Otherwise one of the 270 * following error values is returned: 271 * EIO: non-existent or truncated superblock. 272 * EIO: error reading summary information. 273 * ENOENT: no usable known superblock found. 274 * ENOSPC: failed to allocate space for the superblock. 275 * EINVAL: The previous newfs operation on this volume did not complete. 276 * The administrator must complete newfs before using this volume. 277 */ 278 int 279 ffs_sbget(void *devfd, struct fs **fsp, off_t altsblock, 280 struct malloc_type *filltype, 281 int (*readfunc)(void *devfd, off_t loc, void **bufp, int size)) 282 { 283 struct fs *fs; 284 int i, error, size, blks; 285 uint8_t *space; 286 int32_t *lp; 287 int chkhash; 288 char *buf; 289 290 fs = NULL; 291 *fsp = NULL; 292 chkhash = 1; 293 if (altsblock >= 0) { 294 if ((error = readsuper(devfd, &fs, altsblock, 1, chkhash, 295 readfunc)) != 0) { 296 if (fs != NULL) 297 UFS_FREE(fs, filltype); 298 return (error); 299 } 300 } else { 301 if (altsblock == STDSB_NOHASHFAIL) 302 chkhash = 0; 303 for (i = 0; sblock_try[i] != -1; i++) { 304 if ((error = readsuper(devfd, &fs, sblock_try[i], 0, 305 chkhash, readfunc)) == 0) 306 break; 307 if (fs != NULL) { 308 UFS_FREE(fs, filltype); 309 fs = NULL; 310 } 311 if (error == ENOENT) 312 continue; 313 return (error); 314 } 315 if (sblock_try[i] == -1) 316 return (ENOENT); 317 } 318 /* 319 * Read in the superblock summary information. 320 */ 321 size = fs->fs_cssize; 322 blks = howmany(size, fs->fs_fsize); 323 if (fs->fs_contigsumsize > 0) 324 size += fs->fs_ncg * sizeof(int32_t); 325 size += fs->fs_ncg * sizeof(u_int8_t); 326 /* When running in libufs or libsa, UFS_MALLOC may fail */ 327 if ((space = UFS_MALLOC(size, filltype, M_WAITOK)) == NULL) { 328 UFS_FREE(fs, filltype); 329 return (ENOSPC); 330 } 331 fs->fs_csp = (struct csum *)space; 332 for (i = 0; i < blks; i += fs->fs_frag) { 333 size = fs->fs_bsize; 334 if (i + fs->fs_frag > blks) 335 size = (blks - i) * fs->fs_fsize; 336 buf = NULL; 337 error = (*readfunc)(devfd, 338 dbtob(fsbtodb(fs, fs->fs_csaddr + i)), (void **)&buf, size); 339 if (error) { 340 if (buf != NULL) 341 UFS_FREE(buf, filltype); 342 UFS_FREE(fs->fs_csp, filltype); 343 UFS_FREE(fs, filltype); 344 return (error); 345 } 346 memcpy(space, buf, size); 347 UFS_FREE(buf, filltype); 348 space += size; 349 } 350 if (fs->fs_contigsumsize > 0) { 351 fs->fs_maxcluster = lp = (int32_t *)space; 352 for (i = 0; i < fs->fs_ncg; i++) 353 *lp++ = fs->fs_contigsumsize; 354 space = (uint8_t *)lp; 355 } 356 size = fs->fs_ncg * sizeof(u_int8_t); 357 fs->fs_contigdirs = (u_int8_t *)space; 358 bzero(fs->fs_contigdirs, size); 359 *fsp = fs; 360 return (0); 361 } 362 363 /* 364 * Try to read a superblock from the location specified by sblockloc. 365 * Return zero on success or an errno on failure. 366 */ 367 static int 368 readsuper(void *devfd, struct fs **fsp, off_t sblockloc, int isaltsblk, 369 int chkhash, int (*readfunc)(void *devfd, off_t loc, void **bufp, int size)) 370 { 371 struct fs *fs; 372 int error, res; 373 uint32_t ckhash; 374 375 error = (*readfunc)(devfd, sblockloc, (void **)fsp, SBLOCKSIZE); 376 if (error != 0) 377 return (error); 378 fs = *fsp; 379 if (fs->fs_magic == FS_BAD_MAGIC) 380 return (EINVAL); 381 if (((fs->fs_magic == FS_UFS1_MAGIC && (isaltsblk || 382 sblockloc <= SBLOCK_UFS1)) || 383 (fs->fs_magic == FS_UFS2_MAGIC && (isaltsblk || 384 sblockloc == fs->fs_sblockloc))) && 385 fs->fs_ncg >= 1 && 386 fs->fs_bsize >= MINBSIZE && 387 fs->fs_bsize <= MAXBSIZE && 388 fs->fs_bsize >= roundup(sizeof(struct fs), DEV_BSIZE) && 389 fs->fs_sbsize <= SBLOCKSIZE) { 390 /* 391 * If the filesystem has been run on a kernel without 392 * metadata check hashes, disable them. 393 */ 394 if ((fs->fs_flags & FS_METACKHASH) == 0) 395 fs->fs_metackhash = 0; 396 if (fs->fs_ckhash != (ckhash = ffs_calc_sbhash(fs))) { 397 #ifdef _KERNEL 398 res = uprintf("Superblock check-hash failed: recorded " 399 "check-hash 0x%x != computed check-hash 0x%x%s\n", 400 fs->fs_ckhash, ckhash, 401 chkhash == 0 ? " (Ignored)" : ""); 402 #else 403 res = 0; 404 #endif 405 /* 406 * Print check-hash failure if no controlling terminal 407 * in kernel or always if in user-mode (libufs). 408 */ 409 if (res == 0) 410 printf("Superblock check-hash failed: recorded " 411 "check-hash 0x%x != computed check-hash " 412 "0x%x%s\n", fs->fs_ckhash, ckhash, 413 chkhash == 0 ? " (Ignored)" : ""); 414 if (chkhash == 0) { 415 fs->fs_flags |= FS_NEEDSFSCK; 416 fs->fs_fmod = 1; 417 return (0); 418 } 419 fs->fs_fmod = 0; 420 return (EINVAL); 421 } 422 /* Have to set for old filesystems that predate this field */ 423 fs->fs_sblockactualloc = sblockloc; 424 /* Not yet any summary information */ 425 fs->fs_csp = NULL; 426 return (0); 427 } 428 return (ENOENT); 429 } 430 431 /* 432 * Write a superblock to the devfd device from the memory pointed to by fs. 433 * Write out the superblock summary information if it is present. 434 * 435 * If the write is successful, zero is returned. Otherwise one of the 436 * following error values is returned: 437 * EIO: failed to write superblock. 438 * EIO: failed to write superblock summary information. 439 */ 440 int 441 ffs_sbput(void *devfd, struct fs *fs, off_t loc, 442 int (*writefunc)(void *devfd, off_t loc, void *buf, int size)) 443 { 444 int i, error, blks, size; 445 uint8_t *space; 446 447 /* 448 * If there is summary information, write it first, so if there 449 * is an error, the superblock will not be marked as clean. 450 */ 451 if (fs->fs_csp != NULL) { 452 blks = howmany(fs->fs_cssize, fs->fs_fsize); 453 space = (uint8_t *)fs->fs_csp; 454 for (i = 0; i < blks; i += fs->fs_frag) { 455 size = fs->fs_bsize; 456 if (i + fs->fs_frag > blks) 457 size = (blks - i) * fs->fs_fsize; 458 if ((error = (*writefunc)(devfd, 459 dbtob(fsbtodb(fs, fs->fs_csaddr + i)), 460 space, size)) != 0) 461 return (error); 462 space += size; 463 } 464 } 465 fs->fs_fmod = 0; 466 fs->fs_time = UFS_TIME; 467 fs->fs_ckhash = ffs_calc_sbhash(fs); 468 if ((error = (*writefunc)(devfd, loc, fs, fs->fs_sbsize)) != 0) 469 return (error); 470 return (0); 471 } 472 473 /* 474 * Calculate the check-hash for a superblock. 475 */ 476 uint32_t 477 ffs_calc_sbhash(struct fs *fs) 478 { 479 uint32_t ckhash, save_ckhash; 480 481 /* 482 * A filesystem that was using a superblock ckhash may be moved 483 * to an older kernel that does not support ckhashes. The 484 * older kernel will clear the FS_METACKHASH flag indicating 485 * that it does not update hashes. When the disk is moved back 486 * to a kernel capable of ckhashes it disables them on mount: 487 * 488 * if ((fs->fs_flags & FS_METACKHASH) == 0) 489 * fs->fs_metackhash = 0; 490 * 491 * This leaves (fs->fs_metackhash & CK_SUPERBLOCK) == 0) with an 492 * old stale value in the fs->fs_ckhash field. Thus the need to 493 * just accept what is there. 494 */ 495 if ((fs->fs_metackhash & CK_SUPERBLOCK) == 0) 496 return (fs->fs_ckhash); 497 498 save_ckhash = fs->fs_ckhash; 499 fs->fs_ckhash = 0; 500 /* 501 * If newly read from disk, the caller is responsible for 502 * verifying that fs->fs_sbsize <= SBLOCKSIZE. 503 */ 504 ckhash = calculate_crc32c(~0L, (void *)fs, fs->fs_sbsize); 505 fs->fs_ckhash = save_ckhash; 506 return (ckhash); 507 } 508 509 /* 510 * Update the frsum fields to reflect addition or deletion 511 * of some frags. 512 */ 513 void 514 ffs_fragacct(struct fs *fs, int fragmap, int32_t fraglist[], int cnt) 515 { 516 int inblk; 517 int field, subfield; 518 int siz, pos; 519 520 inblk = (int)(fragtbl[fs->fs_frag][fragmap]) << 1; 521 fragmap <<= 1; 522 for (siz = 1; siz < fs->fs_frag; siz++) { 523 if ((inblk & (1 << (siz + (fs->fs_frag % NBBY)))) == 0) 524 continue; 525 field = around[siz]; 526 subfield = inside[siz]; 527 for (pos = siz; pos <= fs->fs_frag; pos++) { 528 if ((fragmap & field) == subfield) { 529 fraglist[siz] += cnt; 530 pos += siz; 531 field <<= siz; 532 subfield <<= siz; 533 } 534 field <<= 1; 535 subfield <<= 1; 536 } 537 } 538 } 539 540 /* 541 * block operations 542 * 543 * check if a block is available 544 */ 545 int 546 ffs_isblock(struct fs *fs, unsigned char *cp, ufs1_daddr_t h) 547 { 548 unsigned char mask; 549 550 switch ((int)fs->fs_frag) { 551 case 8: 552 return (cp[h] == 0xff); 553 case 4: 554 mask = 0x0f << ((h & 0x1) << 2); 555 return ((cp[h >> 1] & mask) == mask); 556 case 2: 557 mask = 0x03 << ((h & 0x3) << 1); 558 return ((cp[h >> 2] & mask) == mask); 559 case 1: 560 mask = 0x01 << (h & 0x7); 561 return ((cp[h >> 3] & mask) == mask); 562 default: 563 #ifdef _KERNEL 564 panic("ffs_isblock"); 565 #endif 566 break; 567 } 568 return (0); 569 } 570 571 /* 572 * check if a block is free 573 */ 574 int 575 ffs_isfreeblock(struct fs *fs, u_char *cp, ufs1_daddr_t h) 576 { 577 578 switch ((int)fs->fs_frag) { 579 case 8: 580 return (cp[h] == 0); 581 case 4: 582 return ((cp[h >> 1] & (0x0f << ((h & 0x1) << 2))) == 0); 583 case 2: 584 return ((cp[h >> 2] & (0x03 << ((h & 0x3) << 1))) == 0); 585 case 1: 586 return ((cp[h >> 3] & (0x01 << (h & 0x7))) == 0); 587 default: 588 #ifdef _KERNEL 589 panic("ffs_isfreeblock"); 590 #endif 591 break; 592 } 593 return (0); 594 } 595 596 /* 597 * take a block out of the map 598 */ 599 void 600 ffs_clrblock(struct fs *fs, u_char *cp, ufs1_daddr_t h) 601 { 602 603 switch ((int)fs->fs_frag) { 604 case 8: 605 cp[h] = 0; 606 return; 607 case 4: 608 cp[h >> 1] &= ~(0x0f << ((h & 0x1) << 2)); 609 return; 610 case 2: 611 cp[h >> 2] &= ~(0x03 << ((h & 0x3) << 1)); 612 return; 613 case 1: 614 cp[h >> 3] &= ~(0x01 << (h & 0x7)); 615 return; 616 default: 617 #ifdef _KERNEL 618 panic("ffs_clrblock"); 619 #endif 620 break; 621 } 622 } 623 624 /* 625 * put a block into the map 626 */ 627 void 628 ffs_setblock(struct fs *fs, unsigned char *cp, ufs1_daddr_t h) 629 { 630 631 switch ((int)fs->fs_frag) { 632 633 case 8: 634 cp[h] = 0xff; 635 return; 636 case 4: 637 cp[h >> 1] |= (0x0f << ((h & 0x1) << 2)); 638 return; 639 case 2: 640 cp[h >> 2] |= (0x03 << ((h & 0x3) << 1)); 641 return; 642 case 1: 643 cp[h >> 3] |= (0x01 << (h & 0x7)); 644 return; 645 default: 646 #ifdef _KERNEL 647 panic("ffs_setblock"); 648 #endif 649 break; 650 } 651 } 652 653 /* 654 * Update the cluster map because of an allocation or free. 655 * 656 * Cnt == 1 means free; cnt == -1 means allocating. 657 */ 658 void 659 ffs_clusteracct(struct fs *fs, struct cg *cgp, ufs1_daddr_t blkno, int cnt) 660 { 661 int32_t *sump; 662 int32_t *lp; 663 u_char *freemapp, *mapp; 664 int i, start, end, forw, back, map; 665 u_int bit; 666 667 if (fs->fs_contigsumsize <= 0) 668 return; 669 freemapp = cg_clustersfree(cgp); 670 sump = cg_clustersum(cgp); 671 /* 672 * Allocate or clear the actual block. 673 */ 674 if (cnt > 0) 675 setbit(freemapp, blkno); 676 else 677 clrbit(freemapp, blkno); 678 /* 679 * Find the size of the cluster going forward. 680 */ 681 start = blkno + 1; 682 end = start + fs->fs_contigsumsize; 683 if (end >= cgp->cg_nclusterblks) 684 end = cgp->cg_nclusterblks; 685 mapp = &freemapp[start / NBBY]; 686 map = *mapp++; 687 bit = 1U << (start % NBBY); 688 for (i = start; i < end; i++) { 689 if ((map & bit) == 0) 690 break; 691 if ((i & (NBBY - 1)) != (NBBY - 1)) { 692 bit <<= 1; 693 } else { 694 map = *mapp++; 695 bit = 1; 696 } 697 } 698 forw = i - start; 699 /* 700 * Find the size of the cluster going backward. 701 */ 702 start = blkno - 1; 703 end = start - fs->fs_contigsumsize; 704 if (end < 0) 705 end = -1; 706 mapp = &freemapp[start / NBBY]; 707 map = *mapp--; 708 bit = 1U << (start % NBBY); 709 for (i = start; i > end; i--) { 710 if ((map & bit) == 0) 711 break; 712 if ((i & (NBBY - 1)) != 0) { 713 bit >>= 1; 714 } else { 715 map = *mapp--; 716 bit = 1U << (NBBY - 1); 717 } 718 } 719 back = start - i; 720 /* 721 * Account for old cluster and the possibly new forward and 722 * back clusters. 723 */ 724 i = back + forw + 1; 725 if (i > fs->fs_contigsumsize) 726 i = fs->fs_contigsumsize; 727 sump[i] += cnt; 728 if (back > 0) 729 sump[back] -= cnt; 730 if (forw > 0) 731 sump[forw] -= cnt; 732 /* 733 * Update cluster summary information. 734 */ 735 lp = &sump[fs->fs_contigsumsize]; 736 for (i = fs->fs_contigsumsize; i > 0; i--) 737 if (*lp-- > 0) 738 break; 739 fs->fs_maxcluster[cgp->cg_cgx] = i; 740 } 741