ffs_balloc.c revision 329099
1/* $NetBSD: ffs_balloc.c,v 1.13 2004/06/20 22:20:18 jmc 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#include <sys/cdefs.h> 36__FBSDID("$FreeBSD: stable/11/usr.sbin/makefs/ffs/ffs_balloc.c 329099 2018-02-10 04:37:44Z kevans $"); 37 38#include <sys/param.h> 39#include <sys/time.h> 40 41#include <assert.h> 42#include <errno.h> 43#include <stdio.h> 44#include <stdlib.h> 45#include <string.h> 46 47#include "makefs.h" 48 49#include <ufs/ufs/dinode.h> 50#include <ufs/ffs/fs.h> 51 52#include "ffs/ufs_bswap.h" 53#include "ffs/buf.h" 54#include "ffs/ufs_inode.h" 55#include "ffs/ffs_extern.h" 56 57static int ffs_balloc_ufs1(struct inode *, off_t, int, struct buf **); 58static int ffs_balloc_ufs2(struct inode *, off_t, int, struct buf **); 59 60/* 61 * Balloc defines the structure of file system storage 62 * by allocating the physical blocks on a device given 63 * the inode and the logical block number in a file. 64 * 65 * Assume: flags == B_SYNC | B_CLRBUF 66 */ 67 68int 69ffs_balloc(struct inode *ip, off_t offset, int bufsize, struct buf **bpp) 70{ 71 if (ip->i_fs->fs_magic == FS_UFS2_MAGIC) 72 return ffs_balloc_ufs2(ip, offset, bufsize, bpp); 73 else 74 return ffs_balloc_ufs1(ip, offset, bufsize, bpp); 75} 76 77static int 78ffs_balloc_ufs1(struct inode *ip, off_t offset, int bufsize, struct buf **bpp) 79{ 80 daddr_t lbn, lastlbn; 81 int size; 82 int32_t nb; 83 struct buf *bp, *nbp; 84 struct fs *fs = ip->i_fs; 85 struct indir indirs[NIADDR + 2]; 86 daddr_t newb, pref; 87 int32_t *bap; 88 int osize, nsize, num, i, error; 89 int32_t *allocblk, allociblk[NIADDR + 1]; 90 int32_t *allocib; 91 const int needswap = UFS_FSNEEDSWAP(fs); 92 struct vnode vp = { ip->i_fd, ip->i_fs, NULL, 0 }; 93 94 lbn = lblkno(fs, offset); 95 size = blkoff(fs, offset) + bufsize; 96 if (bpp != NULL) { 97 *bpp = NULL; 98 } 99 100 assert(size <= fs->fs_bsize); 101 if (lbn < 0) 102 return (EFBIG); 103 104 /* 105 * If the next write will extend the file into a new block, 106 * and the file is currently composed of a fragment 107 * this fragment has to be extended to be a full block. 108 */ 109 110 lastlbn = lblkno(fs, ip->i_ffs1_size); 111 if (lastlbn < NDADDR && lastlbn < lbn) { 112 nb = lastlbn; 113 osize = blksize(fs, ip, nb); 114 if (osize < fs->fs_bsize && osize > 0) { 115 warnx("need to ffs_realloccg; not supported!"); 116 abort(); 117 } 118 } 119 120 /* 121 * The first NDADDR blocks are direct blocks 122 */ 123 124 if (lbn < NDADDR) { 125 nb = ufs_rw32(ip->i_ffs1_db[lbn], needswap); 126 if (nb != 0 && ip->i_ffs1_size >= lblktosize(fs, lbn + 1)) { 127 128 /* 129 * The block is an already-allocated direct block 130 * and the file already extends past this block, 131 * thus this must be a whole block. 132 * Just read the block (if requested). 133 */ 134 135 if (bpp != NULL) { 136 error = bread(&vp, lbn, fs->fs_bsize, NULL, 137 bpp); 138 if (error) { 139 brelse(*bpp, 0); 140 return (error); 141 } 142 } 143 return (0); 144 } 145 if (nb != 0) { 146 147 /* 148 * Consider need to reallocate a fragment. 149 */ 150 151 osize = fragroundup(fs, blkoff(fs, ip->i_ffs1_size)); 152 nsize = fragroundup(fs, size); 153 if (nsize <= osize) { 154 155 /* 156 * The existing block is already 157 * at least as big as we want. 158 * Just read the block (if requested). 159 */ 160 161 if (bpp != NULL) { 162 error = bread(&vp, lbn, osize, NULL, 163 bpp); 164 if (error) { 165 brelse(*bpp, 0); 166 return (error); 167 } 168 } 169 return 0; 170 } else { 171 warnx("need to ffs_realloccg; not supported!"); 172 abort(); 173 } 174 } else { 175 176 /* 177 * the block was not previously allocated, 178 * allocate a new block or fragment. 179 */ 180 181 if (ip->i_ffs1_size < lblktosize(fs, lbn + 1)) 182 nsize = fragroundup(fs, size); 183 else 184 nsize = fs->fs_bsize; 185 error = ffs_alloc(ip, lbn, 186 ffs_blkpref_ufs1(ip, lbn, (int)lbn, 187 &ip->i_ffs1_db[0]), 188 nsize, &newb); 189 if (error) 190 return (error); 191 if (bpp != NULL) { 192 bp = getblk(&vp, lbn, nsize, 0, 0, 0); 193 bp->b_blkno = fsbtodb(fs, newb); 194 clrbuf(bp); 195 *bpp = bp; 196 } 197 } 198 ip->i_ffs1_db[lbn] = ufs_rw32((int32_t)newb, needswap); 199 return (0); 200 } 201 202 /* 203 * Determine the number of levels of indirection. 204 */ 205 206 pref = 0; 207 if ((error = ufs_getlbns(ip, lbn, indirs, &num)) != 0) 208 return (error); 209 210 if (num < 1) { 211 warnx("ffs_balloc: ufs_getlbns returned indirect block"); 212 abort(); 213 } 214 215 /* 216 * Fetch the first indirect block allocating if necessary. 217 */ 218 219 --num; 220 nb = ufs_rw32(ip->i_ffs1_ib[indirs[0].in_off], needswap); 221 allocib = NULL; 222 allocblk = allociblk; 223 if (nb == 0) { 224 pref = ffs_blkpref_ufs1(ip, lbn, 0, (int32_t *)0); 225 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 226 if (error) 227 return error; 228 nb = newb; 229 *allocblk++ = nb; 230 bp = getblk(&vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0, 0); 231 bp->b_blkno = fsbtodb(fs, nb); 232 clrbuf(bp); 233 /* 234 * Write synchronously so that indirect blocks 235 * never point at garbage. 236 */ 237 if ((error = bwrite(bp)) != 0) 238 return error; 239 allocib = &ip->i_ffs1_ib[indirs[0].in_off]; 240 *allocib = ufs_rw32((int32_t)nb, needswap); 241 } 242 243 /* 244 * Fetch through the indirect blocks, allocating as necessary. 245 */ 246 247 for (i = 1;;) { 248 error = bread(&vp, indirs[i].in_lbn, fs->fs_bsize, NULL, &bp); 249 if (error) { 250 brelse(bp, 0); 251 return error; 252 } 253 bap = (int32_t *)bp->b_data; 254 nb = ufs_rw32(bap[indirs[i].in_off], needswap); 255 if (i == num) 256 break; 257 i++; 258 if (nb != 0) { 259 brelse(bp, 0); 260 continue; 261 } 262 if (pref == 0) 263 pref = ffs_blkpref_ufs1(ip, lbn, 0, (int32_t *)0); 264 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 265 if (error) { 266 brelse(bp, 0); 267 return error; 268 } 269 nb = newb; 270 *allocblk++ = nb; 271 nbp = getblk(&vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0, 0); 272 nbp->b_blkno = fsbtodb(fs, nb); 273 clrbuf(nbp); 274 /* 275 * Write synchronously so that indirect blocks 276 * never point at garbage. 277 */ 278 279 if ((error = bwrite(nbp)) != 0) { 280 brelse(bp, 0); 281 return error; 282 } 283 bap[indirs[i - 1].in_off] = ufs_rw32(nb, needswap); 284 285 bwrite(bp); 286 } 287 288 /* 289 * Get the data block, allocating if necessary. 290 */ 291 292 if (nb == 0) { 293 pref = ffs_blkpref_ufs1(ip, lbn, indirs[num].in_off, &bap[0]); 294 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 295 if (error) { 296 brelse(bp, 0); 297 return error; 298 } 299 nb = newb; 300 *allocblk++ = nb; 301 if (bpp != NULL) { 302 nbp = getblk(&vp, lbn, fs->fs_bsize, 0, 0, 0); 303 nbp->b_blkno = fsbtodb(fs, nb); 304 clrbuf(nbp); 305 *bpp = nbp; 306 } 307 bap[indirs[num].in_off] = ufs_rw32(nb, needswap); 308 309 /* 310 * If required, write synchronously, otherwise use 311 * delayed write. 312 */ 313 bwrite(bp); 314 return (0); 315 } 316 brelse(bp, 0); 317 if (bpp != NULL) { 318 error = bread(&vp, lbn, (int)fs->fs_bsize, NULL, &nbp); 319 if (error) { 320 brelse(nbp, 0); 321 return error; 322 } 323 *bpp = nbp; 324 } 325 return (0); 326} 327 328static int 329ffs_balloc_ufs2(struct inode *ip, off_t offset, int bufsize, struct buf **bpp) 330{ 331 daddr_t lbn, lastlbn; 332 int size; 333 struct buf *bp, *nbp; 334 struct fs *fs = ip->i_fs; 335 struct indir indirs[NIADDR + 2]; 336 daddr_t newb, pref, nb; 337 int64_t *bap; 338 int osize, nsize, num, i, error; 339 int64_t *allocblk, allociblk[NIADDR + 1]; 340 int64_t *allocib; 341 const int needswap = UFS_FSNEEDSWAP(fs); 342 struct vnode vp = { ip->i_fd, ip->i_fs, NULL, 0 }; 343 344 lbn = lblkno(fs, offset); 345 size = blkoff(fs, offset) + bufsize; 346 if (bpp != NULL) { 347 *bpp = NULL; 348 } 349 350 assert(size <= fs->fs_bsize); 351 if (lbn < 0) 352 return (EFBIG); 353 354 /* 355 * If the next write will extend the file into a new block, 356 * and the file is currently composed of a fragment 357 * this fragment has to be extended to be a full block. 358 */ 359 360 lastlbn = lblkno(fs, ip->i_ffs2_size); 361 if (lastlbn < NDADDR && lastlbn < lbn) { 362 nb = lastlbn; 363 osize = blksize(fs, ip, nb); 364 if (osize < fs->fs_bsize && osize > 0) { 365 warnx("need to ffs_realloccg; not supported!"); 366 abort(); 367 } 368 } 369 370 /* 371 * The first NDADDR blocks are direct blocks 372 */ 373 374 if (lbn < NDADDR) { 375 nb = ufs_rw64(ip->i_ffs2_db[lbn], needswap); 376 if (nb != 0 && ip->i_ffs2_size >= lblktosize(fs, lbn + 1)) { 377 378 /* 379 * The block is an already-allocated direct block 380 * and the file already extends past this block, 381 * thus this must be a whole block. 382 * Just read the block (if requested). 383 */ 384 385 if (bpp != NULL) { 386 error = bread(&vp, lbn, fs->fs_bsize, NULL, 387 bpp); 388 if (error) { 389 brelse(*bpp, 0); 390 return (error); 391 } 392 } 393 return (0); 394 } 395 if (nb != 0) { 396 397 /* 398 * Consider need to reallocate a fragment. 399 */ 400 401 osize = fragroundup(fs, blkoff(fs, ip->i_ffs2_size)); 402 nsize = fragroundup(fs, size); 403 if (nsize <= osize) { 404 405 /* 406 * The existing block is already 407 * at least as big as we want. 408 * Just read the block (if requested). 409 */ 410 411 if (bpp != NULL) { 412 error = bread(&vp, lbn, osize, NULL, 413 bpp); 414 if (error) { 415 brelse(*bpp, 0); 416 return (error); 417 } 418 } 419 return 0; 420 } else { 421 warnx("need to ffs_realloccg; not supported!"); 422 abort(); 423 } 424 } else { 425 426 /* 427 * the block was not previously allocated, 428 * allocate a new block or fragment. 429 */ 430 431 if (ip->i_ffs2_size < lblktosize(fs, lbn + 1)) 432 nsize = fragroundup(fs, size); 433 else 434 nsize = fs->fs_bsize; 435 error = ffs_alloc(ip, lbn, 436 ffs_blkpref_ufs2(ip, lbn, (int)lbn, 437 &ip->i_ffs2_db[0]), 438 nsize, &newb); 439 if (error) 440 return (error); 441 if (bpp != NULL) { 442 bp = getblk(&vp, lbn, nsize, 0, 0, 0); 443 bp->b_blkno = fsbtodb(fs, newb); 444 clrbuf(bp); 445 *bpp = bp; 446 } 447 } 448 ip->i_ffs2_db[lbn] = ufs_rw64(newb, needswap); 449 return (0); 450 } 451 452 /* 453 * Determine the number of levels of indirection. 454 */ 455 456 pref = 0; 457 if ((error = ufs_getlbns(ip, lbn, indirs, &num)) != 0) 458 return (error); 459 460 if (num < 1) { 461 warnx("ffs_balloc: ufs_getlbns returned indirect block"); 462 abort(); 463 } 464 465 /* 466 * Fetch the first indirect block allocating if necessary. 467 */ 468 469 --num; 470 nb = ufs_rw64(ip->i_ffs2_ib[indirs[0].in_off], needswap); 471 allocib = NULL; 472 allocblk = allociblk; 473 if (nb == 0) { 474 pref = ffs_blkpref_ufs2(ip, lbn, 0, (int64_t *)0); 475 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 476 if (error) 477 return error; 478 nb = newb; 479 *allocblk++ = nb; 480 bp = getblk(&vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0, 0); 481 bp->b_blkno = fsbtodb(fs, nb); 482 clrbuf(bp); 483 /* 484 * Write synchronously so that indirect blocks 485 * never point at garbage. 486 */ 487 if ((error = bwrite(bp)) != 0) 488 return error; 489 allocib = &ip->i_ffs2_ib[indirs[0].in_off]; 490 *allocib = ufs_rw64(nb, needswap); 491 } 492 493 /* 494 * Fetch through the indirect blocks, allocating as necessary. 495 */ 496 497 for (i = 1;;) { 498 error = bread(&vp, indirs[i].in_lbn, fs->fs_bsize, NULL, &bp); 499 if (error) { 500 brelse(bp, 0); 501 return error; 502 } 503 bap = (int64_t *)bp->b_data; 504 nb = ufs_rw64(bap[indirs[i].in_off], needswap); 505 if (i == num) 506 break; 507 i++; 508 if (nb != 0) { 509 brelse(bp, 0); 510 continue; 511 } 512 if (pref == 0) 513 pref = ffs_blkpref_ufs2(ip, lbn, 0, (int64_t *)0); 514 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 515 if (error) { 516 brelse(bp, 0); 517 return error; 518 } 519 nb = newb; 520 *allocblk++ = nb; 521 nbp = getblk(&vp, indirs[i].in_lbn, fs->fs_bsize, 0, 0, 0); 522 nbp->b_blkno = fsbtodb(fs, nb); 523 clrbuf(nbp); 524 /* 525 * Write synchronously so that indirect blocks 526 * never point at garbage. 527 */ 528 529 if ((error = bwrite(nbp)) != 0) { 530 brelse(bp, 0); 531 return error; 532 } 533 bap[indirs[i - 1].in_off] = ufs_rw64(nb, needswap); 534 535 bwrite(bp); 536 } 537 538 /* 539 * Get the data block, allocating if necessary. 540 */ 541 542 if (nb == 0) { 543 pref = ffs_blkpref_ufs2(ip, lbn, indirs[num].in_off, &bap[0]); 544 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 545 if (error) { 546 brelse(bp, 0); 547 return error; 548 } 549 nb = newb; 550 *allocblk++ = nb; 551 if (bpp != NULL) { 552 nbp = getblk(&vp, lbn, fs->fs_bsize, 0, 0, 0); 553 nbp->b_blkno = fsbtodb(fs, nb); 554 clrbuf(nbp); 555 *bpp = nbp; 556 } 557 bap[indirs[num].in_off] = ufs_rw64(nb, needswap); 558 559 /* 560 * If required, write synchronously, otherwise use 561 * delayed write. 562 */ 563 bwrite(bp); 564 return (0); 565 } 566 brelse(bp, 0); 567 if (bpp != NULL) { 568 error = bread(&vp, lbn, (int)fs->fs_bsize, NULL, &nbp); 569 if (error) { 570 brelse(nbp, 0); 571 return error; 572 } 573 *bpp = nbp; 574 } 575 return (0); 576} 577