ffs_balloc.c revision 1.22
1 /* $NetBSD: ffs_balloc.c,v 1.22 2022/11/17 06:40:41 chs Exp $ */ 2 /* From NetBSD: ffs_balloc.c,v 1.25 2001/08/08 08:36:36 lukem Exp */ 3 4 /* 5 * Copyright (c) 1982, 1986, 1989, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * @(#)ffs_balloc.c 8.8 (Berkeley) 6/16/95 33 */ 34 35 #if HAVE_NBTOOL_CONFIG_H 36 #include "nbtool_config.h" 37 #endif 38 39 #include <sys/cdefs.h> 40 #if defined(__RCSID) && !defined(__lint) 41 __RCSID("$NetBSD: ffs_balloc.c,v 1.22 2022/11/17 06:40:41 chs Exp $"); 42 #endif /* !__lint */ 43 44 #include <sys/param.h> 45 #include <sys/time.h> 46 47 #include <assert.h> 48 #include <errno.h> 49 #include <stdio.h> 50 #include <stdlib.h> 51 #include <string.h> 52 53 #include "makefs.h" 54 55 #include <ufs/ufs/dinode.h> 56 #include <ufs/ufs/ufs_bswap.h> 57 #include <ufs/ffs/fs.h> 58 59 #include "ffs/buf.h" 60 #include "ffs/ufs_inode.h" 61 #include "ffs/ffs_extern.h" 62 63 static int ffs_balloc_ufs1(struct inode *, off_t, int, struct buf **); 64 static int ffs_balloc_ufs2(struct inode *, off_t, int, struct buf **); 65 66 /* 67 * Balloc defines the structure of file system storage 68 * by allocating the physical blocks on a device given 69 * the inode and the logical block number in a file. 70 * 71 * Assume: flags == B_SYNC | B_CLRBUF 72 */ 73 74 int 75 ffs_balloc(struct inode *ip, off_t offset, int bufsize, struct buf **bpp) 76 { 77 if (ip->i_fs->fs_magic == FS_UFS2_MAGIC || 78 ip->i_fs->fs_magic == FS_UFS2EA_MAGIC) 79 return ffs_balloc_ufs2(ip, offset, bufsize, bpp); 80 else 81 return ffs_balloc_ufs1(ip, offset, bufsize, bpp); 82 } 83 84 static int 85 ffs_balloc_ufs1(struct inode *ip, off_t offset, int bufsize, struct buf **bpp) 86 { 87 daddr_t lbn, lastlbn; 88 int size; 89 int32_t nb; 90 struct buf *bp, *nbp; 91 struct fs *fs = ip->i_fs; 92 struct indir indirs[UFS_NIADDR + 2]; 93 daddr_t newb, pref; 94 int32_t *bap; 95 int osize, nsize, num, i, error; 96 int32_t *allocblk, allociblk[UFS_NIADDR + 1]; 97 int32_t *allocib; 98 const int needswap = UFS_FSNEEDSWAP(fs); 99 100 lbn = ffs_lblkno(fs, offset); 101 size = ffs_blkoff(fs, offset) + bufsize; 102 if (bpp != NULL) { 103 *bpp = NULL; 104 } 105 106 assert(size <= fs->fs_bsize); 107 if (lbn < 0) 108 return (EFBIG); 109 110 /* 111 * If the next write will extend the file into a new block, 112 * and the file is currently composed of a fragment 113 * this fragment has to be extended to be a full block. 114 */ 115 116 lastlbn = ffs_lblkno(fs, ip->i_ffs1_size); 117 if (lastlbn < UFS_NDADDR && lastlbn < lbn) { 118 nb = lastlbn; 119 osize = ffs_blksize(fs, ip, nb); 120 if (osize < fs->fs_bsize && osize > 0) { 121 warnx("need to ffs_realloccg; not supported!"); 122 abort(); 123 } 124 } 125 126 /* 127 * The first UFS_NDADDR blocks are direct blocks 128 */ 129 130 if (lbn < UFS_NDADDR) { 131 nb = ufs_rw32(ip->i_ffs1_db[lbn], needswap); 132 if (nb != 0 && ip->i_ffs1_size >= ffs_lblktosize(fs, lbn + 1)) { 133 134 /* 135 * The block is an already-allocated direct block 136 * and the file already extends past this block, 137 * thus this must be a whole block. 138 * Just read the block (if requested). 139 */ 140 141 if (bpp != NULL) { 142 error = bread(ip->i_devvp, lbn, fs->fs_bsize, 143 0, bpp); 144 if (error) { 145 brelse(*bpp, 0); 146 return (error); 147 } 148 } 149 return (0); 150 } 151 if (nb != 0) { 152 153 /* 154 * Consider need to reallocate a fragment. 155 */ 156 157 osize = ffs_fragroundup(fs, ffs_blkoff(fs, ip->i_ffs1_size)); 158 nsize = ffs_fragroundup(fs, size); 159 if (nsize <= osize) { 160 161 /* 162 * The existing block is already 163 * at least as big as we want. 164 * Just read the block (if requested). 165 */ 166 167 if (bpp != NULL) { 168 error = bread(ip->i_devvp, lbn, osize, 169 0, bpp); 170 if (error) { 171 brelse(*bpp, 0); 172 return (error); 173 } 174 } 175 return 0; 176 } else { 177 warnx("need to ffs_realloccg; not supported!"); 178 abort(); 179 } 180 } else { 181 182 /* 183 * the block was not previously allocated, 184 * allocate a new block or fragment. 185 */ 186 187 if (ip->i_ffs1_size < ffs_lblktosize(fs, lbn + 1)) 188 nsize = ffs_fragroundup(fs, size); 189 else 190 nsize = fs->fs_bsize; 191 error = ffs_alloc(ip, lbn, 192 ffs_blkpref_ufs1(ip, lbn, (int)lbn, 193 &ip->i_ffs1_db[0]), 194 nsize, &newb); 195 if (error) 196 return (error); 197 if (bpp != NULL) { 198 bp = getblk(ip->i_devvp, lbn, nsize, 0, 0); 199 bp->b_blkno = FFS_FSBTODB(fs, newb); 200 clrbuf(bp); 201 *bpp = bp; 202 } 203 } 204 ip->i_ffs1_db[lbn] = ufs_rw32((int32_t)newb, needswap); 205 return (0); 206 } 207 208 /* 209 * Determine the number of levels of indirection. 210 */ 211 212 pref = 0; 213 if ((error = ufs_getlbns(ip, lbn, indirs, &num)) != 0) 214 return (error); 215 216 if (num < 1) { 217 warnx("ffs_balloc: ufs_getlbns returned indirect block"); 218 abort(); 219 } 220 221 /* 222 * Fetch the first indirect block allocating if necessary. 223 */ 224 225 --num; 226 nb = ufs_rw32(ip->i_ffs1_ib[indirs[0].in_off], needswap); 227 allocib = NULL; 228 allocblk = allociblk; 229 if (nb == 0) { 230 pref = ffs_blkpref_ufs1(ip, lbn, 0, (int32_t *)0); 231 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 232 if (error) 233 return error; 234 nb = newb; 235 *allocblk++ = nb; 236 bp = getblk(ip->i_devvp, indirs[1].in_lbn, fs->fs_bsize, 0, 0); 237 bp->b_blkno = FFS_FSBTODB(fs, nb); 238 clrbuf(bp); 239 /* 240 * Write synchronously so that indirect blocks 241 * never point at garbage. 242 */ 243 if ((error = bwrite(bp)) != 0) 244 return error; 245 allocib = &ip->i_ffs1_ib[indirs[0].in_off]; 246 *allocib = ufs_rw32((int32_t)nb, needswap); 247 } 248 249 /* 250 * Fetch through the indirect blocks, allocating as necessary. 251 */ 252 253 for (i = 1;;) { 254 error = bread(ip->i_devvp, indirs[i].in_lbn, fs->fs_bsize, 255 0, &bp); 256 if (error) { 257 brelse(bp, 0); 258 return error; 259 } 260 bap = (int32_t *)bp->b_data; 261 nb = ufs_rw32(bap[indirs[i].in_off], needswap); 262 if (i == num) 263 break; 264 i++; 265 if (nb != 0) { 266 brelse(bp, 0); 267 continue; 268 } 269 if (pref == 0) 270 pref = ffs_blkpref_ufs1(ip, lbn, 0, (int32_t *)0); 271 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 272 if (error) { 273 brelse(bp, 0); 274 return error; 275 } 276 nb = newb; 277 *allocblk++ = nb; 278 nbp = getblk(ip->i_devvp, indirs[i].in_lbn, fs->fs_bsize, 0, 0); 279 nbp->b_blkno = FFS_FSBTODB(fs, nb); 280 clrbuf(nbp); 281 /* 282 * Write synchronously so that indirect blocks 283 * never point at garbage. 284 */ 285 286 if ((error = bwrite(nbp)) != 0) { 287 brelse(bp, 0); 288 return error; 289 } 290 bap[indirs[i - 1].in_off] = ufs_rw32(nb, needswap); 291 292 bwrite(bp); 293 } 294 295 /* 296 * Get the data block, allocating if necessary. 297 */ 298 299 if (nb == 0) { 300 pref = ffs_blkpref_ufs1(ip, lbn, indirs[num].in_off, &bap[0]); 301 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 302 if (error) { 303 brelse(bp, 0); 304 return error; 305 } 306 nb = newb; 307 *allocblk++ = nb; 308 if (bpp != NULL) { 309 nbp = getblk(ip->i_devvp, lbn, fs->fs_bsize, 0, 0); 310 nbp->b_blkno = FFS_FSBTODB(fs, nb); 311 clrbuf(nbp); 312 *bpp = nbp; 313 } 314 bap[indirs[num].in_off] = ufs_rw32(nb, needswap); 315 316 /* 317 * If required, write synchronously, otherwise use 318 * delayed write. 319 */ 320 bwrite(bp); 321 return (0); 322 } 323 brelse(bp, 0); 324 if (bpp != NULL) { 325 error = bread(ip->i_devvp, lbn, (int)fs->fs_bsize, 0, &nbp); 326 if (error) { 327 brelse(nbp, 0); 328 return error; 329 } 330 *bpp = nbp; 331 } 332 return (0); 333 } 334 335 static int 336 ffs_balloc_ufs2(struct inode *ip, off_t offset, int bufsize, struct buf **bpp) 337 { 338 daddr_t lbn, lastlbn; 339 int size; 340 struct buf *bp, *nbp; 341 struct fs *fs = ip->i_fs; 342 struct indir indirs[UFS_NIADDR + 2]; 343 daddr_t newb, pref, nb; 344 int64_t *bap; 345 int osize, nsize, num, i, error; 346 int64_t *allocblk, allociblk[UFS_NIADDR + 1]; 347 int64_t *allocib; 348 const int needswap = UFS_FSNEEDSWAP(fs); 349 350 lbn = ffs_lblkno(fs, offset); 351 size = ffs_blkoff(fs, offset) + bufsize; 352 if (bpp != NULL) { 353 *bpp = NULL; 354 } 355 356 assert(size <= fs->fs_bsize); 357 if (lbn < 0) 358 return (EFBIG); 359 360 /* 361 * If the next write will extend the file into a new block, 362 * and the file is currently composed of a fragment 363 * this fragment has to be extended to be a full block. 364 */ 365 366 lastlbn = ffs_lblkno(fs, ip->i_ffs2_size); 367 if (lastlbn < UFS_NDADDR && lastlbn < lbn) { 368 nb = lastlbn; 369 osize = ffs_blksize(fs, ip, nb); 370 if (osize < fs->fs_bsize && osize > 0) { 371 warnx("need to ffs_realloccg; not supported!"); 372 abort(); 373 } 374 } 375 376 /* 377 * The first UFS_NDADDR blocks are direct blocks 378 */ 379 380 if (lbn < UFS_NDADDR) { 381 nb = ufs_rw64(ip->i_ffs2_db[lbn], needswap); 382 if (nb != 0 && ip->i_ffs2_size >= ffs_lblktosize(fs, lbn + 1)) { 383 384 /* 385 * The block is an already-allocated direct block 386 * and the file already extends past this block, 387 * thus this must be a whole block. 388 * Just read the block (if requested). 389 */ 390 391 if (bpp != NULL) { 392 error = bread(ip->i_devvp, lbn, fs->fs_bsize, 393 0, bpp); 394 if (error) { 395 brelse(*bpp, 0); 396 return (error); 397 } 398 } 399 return (0); 400 } 401 if (nb != 0) { 402 403 /* 404 * Consider need to reallocate a fragment. 405 */ 406 407 osize = ffs_fragroundup(fs, ffs_blkoff(fs, ip->i_ffs2_size)); 408 nsize = ffs_fragroundup(fs, size); 409 if (nsize <= osize) { 410 411 /* 412 * The existing block is already 413 * at least as big as we want. 414 * Just read the block (if requested). 415 */ 416 417 if (bpp != NULL) { 418 error = bread(ip->i_devvp, lbn, osize, 419 0, bpp); 420 if (error) { 421 brelse(*bpp, 0); 422 return (error); 423 } 424 } 425 return 0; 426 } else { 427 warnx("need to ffs_realloccg; not supported!"); 428 abort(); 429 } 430 } else { 431 432 /* 433 * the block was not previously allocated, 434 * allocate a new block or fragment. 435 */ 436 437 if (ip->i_ffs2_size < ffs_lblktosize(fs, lbn + 1)) 438 nsize = ffs_fragroundup(fs, size); 439 else 440 nsize = fs->fs_bsize; 441 error = ffs_alloc(ip, lbn, 442 ffs_blkpref_ufs2(ip, lbn, (int)lbn, 443 &ip->i_ffs2_db[0]), 444 nsize, &newb); 445 if (error) 446 return (error); 447 if (bpp != NULL) { 448 bp = getblk(ip->i_devvp, lbn, nsize, 0, 0); 449 bp->b_blkno = FFS_FSBTODB(fs, newb); 450 clrbuf(bp); 451 *bpp = bp; 452 } 453 } 454 ip->i_ffs2_db[lbn] = ufs_rw64(newb, needswap); 455 return (0); 456 } 457 458 /* 459 * Determine the number of levels of indirection. 460 */ 461 462 pref = 0; 463 if ((error = ufs_getlbns(ip, lbn, indirs, &num)) != 0) 464 return (error); 465 466 if (num < 1) { 467 warnx("ffs_balloc: ufs_getlbns returned indirect block"); 468 abort(); 469 } 470 471 /* 472 * Fetch the first indirect block allocating if necessary. 473 */ 474 475 --num; 476 nb = ufs_rw64(ip->i_ffs2_ib[indirs[0].in_off], needswap); 477 allocib = NULL; 478 allocblk = allociblk; 479 if (nb == 0) { 480 pref = ffs_blkpref_ufs2(ip, lbn, 0, (int64_t *)0); 481 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 482 if (error) 483 return error; 484 nb = newb; 485 *allocblk++ = nb; 486 bp = getblk(ip->i_devvp, indirs[1].in_lbn, fs->fs_bsize, 0, 0); 487 bp->b_blkno = FFS_FSBTODB(fs, nb); 488 clrbuf(bp); 489 /* 490 * Write synchronously so that indirect blocks 491 * never point at garbage. 492 */ 493 if ((error = bwrite(bp)) != 0) 494 return error; 495 allocib = &ip->i_ffs2_ib[indirs[0].in_off]; 496 *allocib = ufs_rw64(nb, needswap); 497 } 498 499 /* 500 * Fetch through the indirect blocks, allocating as necessary. 501 */ 502 503 for (i = 1;;) { 504 error = bread(ip->i_devvp, indirs[i].in_lbn, fs->fs_bsize, 505 0, &bp); 506 if (error) { 507 brelse(bp, 0); 508 return error; 509 } 510 bap = (int64_t *)bp->b_data; 511 nb = ufs_rw64(bap[indirs[i].in_off], needswap); 512 if (i == num) 513 break; 514 i++; 515 if (nb != 0) { 516 brelse(bp, 0); 517 continue; 518 } 519 if (pref == 0) 520 pref = ffs_blkpref_ufs2(ip, lbn, 0, (int64_t *)0); 521 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 522 if (error) { 523 brelse(bp, 0); 524 return error; 525 } 526 nb = newb; 527 *allocblk++ = nb; 528 nbp = getblk(ip->i_devvp, indirs[i].in_lbn, fs->fs_bsize, 0, 0); 529 nbp->b_blkno = FFS_FSBTODB(fs, nb); 530 clrbuf(nbp); 531 /* 532 * Write synchronously so that indirect blocks 533 * never point at garbage. 534 */ 535 536 if ((error = bwrite(nbp)) != 0) { 537 brelse(bp, 0); 538 return error; 539 } 540 bap[indirs[i - 1].in_off] = ufs_rw64(nb, needswap); 541 542 bwrite(bp); 543 } 544 545 /* 546 * Get the data block, allocating if necessary. 547 */ 548 549 if (nb == 0) { 550 pref = ffs_blkpref_ufs2(ip, lbn, indirs[num].in_off, &bap[0]); 551 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 552 if (error) { 553 brelse(bp, 0); 554 return error; 555 } 556 nb = newb; 557 *allocblk++ = nb; 558 if (bpp != NULL) { 559 nbp = getblk(ip->i_devvp, lbn, fs->fs_bsize, 0, 0); 560 nbp->b_blkno = FFS_FSBTODB(fs, nb); 561 clrbuf(nbp); 562 *bpp = nbp; 563 } 564 bap[indirs[num].in_off] = ufs_rw64(nb, needswap); 565 566 /* 567 * If required, write synchronously, otherwise use 568 * delayed write. 569 */ 570 bwrite(bp); 571 return (0); 572 } 573 brelse(bp, 0); 574 if (bpp != NULL) { 575 error = bread(ip->i_devvp, lbn, (int)fs->fs_bsize, 0, 576 &nbp); 577 if (error) { 578 brelse(nbp, 0); 579 return error; 580 } 581 *bpp = nbp; 582 } 583 return (0); 584 } 585
Indexes created Mon Sep 29 21:09:56 GMT 2025