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("$FreeBSD$"); 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 57 static int ffs_balloc_ufs1(struct inode *, off_t, int, struct buf **); 58 static 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 68 int 69 ffs_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 77 static int 78 ffs_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 93 lbn = lblkno(fs, offset); 94 size = blkoff(fs, offset) + bufsize; 95 if (bpp != NULL) { 96 *bpp = NULL; 97 } 98 99 assert(size <= fs->fs_bsize); 100 if (lbn < 0) 101 return (EFBIG); 102 103 /* 104 * If the next write will extend the file into a new block, 105 * and the file is currently composed of a fragment 106 * this fragment has to be extended to be a full block. 107 */ 108 109 lastlbn = lblkno(fs, ip->i_ffs1_size); 110 if (lastlbn < NDADDR && lastlbn < lbn) { 111 nb = lastlbn; 112 osize = blksize(fs, ip, nb); 113 if (osize < fs->fs_bsize && osize > 0) { 114 warnx("need to ffs_realloccg; not supported!"); 115 abort(); 116 } 117 } 118 119 /* 120 * The first NDADDR blocks are direct blocks 121 */ 122 123 if (lbn < NDADDR) { 124 nb = ufs_rw32(ip->i_ffs1_db[lbn], needswap); 125 if (nb != 0 && ip->i_ffs1_size >= lblktosize(fs, lbn + 1)) { 126 127 /* 128 * The block is an already-allocated direct block 129 * and the file already extends past this block, 130 * thus this must be a whole block. 131 * Just read the block (if requested). 132 */ 133 134 if (bpp != NULL) { 135 error = bread(ip->i_fd, ip->i_fs, lbn, 136 fs->fs_bsize, bpp); 137 if (error) { 138 brelse(*bpp); 139 return (error); 140 } 141 } 142 return (0); 143 } 144 if (nb != 0) { 145 146 /* 147 * Consider need to reallocate a fragment. 148 */ 149 150 osize = fragroundup(fs, blkoff(fs, ip->i_ffs1_size)); 151 nsize = fragroundup(fs, size); 152 if (nsize <= osize) { 153 154 /* 155 * The existing block is already 156 * at least as big as we want. 157 * Just read the block (if requested). 158 */ 159 160 if (bpp != NULL) { 161 error = bread(ip->i_fd, ip->i_fs, lbn, 162 osize, bpp); 163 if (error) { 164 brelse(*bpp); 165 return (error); 166 } 167 } 168 return 0; 169 } else { 170 warnx("need to ffs_realloccg; not supported!"); 171 abort(); 172 } 173 } else { 174 175 /* 176 * the block was not previously allocated, 177 * allocate a new block or fragment. 178 */ 179 180 if (ip->i_ffs1_size < lblktosize(fs, lbn + 1)) 181 nsize = fragroundup(fs, size); 182 else 183 nsize = fs->fs_bsize; 184 error = ffs_alloc(ip, lbn, 185 ffs_blkpref_ufs1(ip, lbn, (int)lbn, 186 &ip->i_ffs1_db[0]), 187 nsize, &newb); 188 if (error) 189 return (error); 190 if (bpp != NULL) { 191 bp = getblk(ip->i_fd, ip->i_fs, lbn, nsize); 192 bp->b_blkno = fsbtodb(fs, newb); 193 clrbuf(bp); 194 *bpp = bp; 195 } 196 } 197 ip->i_ffs1_db[lbn] = ufs_rw32((int32_t)newb, needswap); 198 return (0); 199 } 200 201 /* 202 * Determine the number of levels of indirection. 203 */ 204 205 pref = 0; 206 if ((error = ufs_getlbns(ip, lbn, indirs, &num)) != 0) 207 return (error); 208 209 if (num < 1) { 210 warnx("ffs_balloc: ufs_getlbns returned indirect block"); 211 abort(); 212 } 213 214 /* 215 * Fetch the first indirect block allocating if necessary. 216 */ 217 218 --num; 219 nb = ufs_rw32(ip->i_ffs1_ib[indirs[0].in_off], needswap); 220 allocib = NULL; 221 allocblk = allociblk; 222 if (nb == 0) { 223 pref = ffs_blkpref_ufs1(ip, lbn, 0, (int32_t *)0); 224 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 225 if (error) 226 return error; 227 nb = newb; 228 *allocblk++ = nb; 229 bp = getblk(ip->i_fd, ip->i_fs, indirs[1].in_lbn, fs->fs_bsize); 230 bp->b_blkno = fsbtodb(fs, nb); 231 clrbuf(bp); 232 /* 233 * Write synchronously so that indirect blocks 234 * never point at garbage. 235 */ 236 if ((error = bwrite(bp)) != 0) 237 return error; 238 allocib = &ip->i_ffs1_ib[indirs[0].in_off]; 239 *allocib = ufs_rw32((int32_t)nb, needswap); 240 } 241 242 /* 243 * Fetch through the indirect blocks, allocating as necessary. 244 */ 245 246 for (i = 1;;) { 247 error = bread(ip->i_fd, ip->i_fs, indirs[i].in_lbn, 248 fs->fs_bsize, &bp); 249 if (error) { 250 brelse(bp); 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); 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); 267 return error; 268 } 269 nb = newb; 270 *allocblk++ = nb; 271 nbp = getblk(ip->i_fd, ip->i_fs, indirs[i].in_lbn, 272 fs->fs_bsize); 273 nbp->b_blkno = fsbtodb(fs, nb); 274 clrbuf(nbp); 275 /* 276 * Write synchronously so that indirect blocks 277 * never point at garbage. 278 */ 279 280 if ((error = bwrite(nbp)) != 0) { 281 brelse(bp); 282 return error; 283 } 284 bap[indirs[i - 1].in_off] = ufs_rw32(nb, needswap); 285 286 bwrite(bp); 287 } 288 289 /* 290 * Get the data block, allocating if necessary. 291 */ 292 293 if (nb == 0) { 294 pref = ffs_blkpref_ufs1(ip, lbn, indirs[num].in_off, &bap[0]); 295 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 296 if (error) { 297 brelse(bp); 298 return error; 299 } 300 nb = newb; 301 *allocblk++ = nb; 302 if (bpp != NULL) { 303 nbp = getblk(ip->i_fd, ip->i_fs, lbn, fs->fs_bsize); 304 nbp->b_blkno = fsbtodb(fs, nb); 305 clrbuf(nbp); 306 *bpp = nbp; 307 } 308 bap[indirs[num].in_off] = ufs_rw32(nb, needswap); 309 310 /* 311 * If required, write synchronously, otherwise use 312 * delayed write. 313 */ 314 bwrite(bp); 315 return (0); 316 } 317 brelse(bp); 318 if (bpp != NULL) { 319 error = bread(ip->i_fd, ip->i_fs, lbn, (int)fs->fs_bsize, &nbp); 320 if (error) { 321 brelse(nbp); 322 return error; 323 } 324 *bpp = nbp; 325 } 326 return (0); 327 } 328 329 static int 330 ffs_balloc_ufs2(struct inode *ip, off_t offset, int bufsize, struct buf **bpp) 331 { 332 daddr_t lbn, lastlbn; 333 int size; 334 struct buf *bp, *nbp; 335 struct fs *fs = ip->i_fs; 336 struct indir indirs[NIADDR + 2]; 337 daddr_t newb, pref, nb; 338 int64_t *bap; 339 int osize, nsize, num, i, error; 340 int64_t *allocblk, allociblk[NIADDR + 1]; 341 int64_t *allocib; 342 const int needswap = UFS_FSNEEDSWAP(fs); 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(ip->i_fd, ip->i_fs, lbn, 387 fs->fs_bsize, bpp); 388 if (error) { 389 brelse(*bpp); 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(ip->i_fd, ip->i_fs, lbn, 413 osize, bpp); 414 if (error) { 415 brelse(*bpp); 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(ip->i_fd, ip->i_fs, lbn, nsize); 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(ip->i_fd, ip->i_fs, indirs[1].in_lbn, fs->fs_bsize); 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(ip->i_fd, ip->i_fs, indirs[i].in_lbn, 499 fs->fs_bsize, &bp); 500 if (error) { 501 brelse(bp); 502 return error; 503 } 504 bap = (int64_t *)bp->b_data; 505 nb = ufs_rw64(bap[indirs[i].in_off], needswap); 506 if (i == num) 507 break; 508 i++; 509 if (nb != 0) { 510 brelse(bp); 511 continue; 512 } 513 if (pref == 0) 514 pref = ffs_blkpref_ufs2(ip, lbn, 0, (int64_t *)0); 515 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 516 if (error) { 517 brelse(bp); 518 return error; 519 } 520 nb = newb; 521 *allocblk++ = nb; 522 nbp = getblk(ip->i_fd, ip->i_fs, indirs[i].in_lbn, 523 fs->fs_bsize); 524 nbp->b_blkno = fsbtodb(fs, nb); 525 clrbuf(nbp); 526 /* 527 * Write synchronously so that indirect blocks 528 * never point at garbage. 529 */ 530 531 if ((error = bwrite(nbp)) != 0) { 532 brelse(bp); 533 return error; 534 } 535 bap[indirs[i - 1].in_off] = ufs_rw64(nb, needswap); 536 537 bwrite(bp); 538 } 539 540 /* 541 * Get the data block, allocating if necessary. 542 */ 543 544 if (nb == 0) { 545 pref = ffs_blkpref_ufs2(ip, lbn, indirs[num].in_off, &bap[0]); 546 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 547 if (error) { 548 brelse(bp); 549 return error; 550 } 551 nb = newb; 552 *allocblk++ = nb; 553 if (bpp != NULL) { 554 nbp = getblk(ip->i_fd, ip->i_fs, lbn, fs->fs_bsize); 555 nbp->b_blkno = fsbtodb(fs, nb); 556 clrbuf(nbp); 557 *bpp = nbp; 558 } 559 bap[indirs[num].in_off] = ufs_rw64(nb, needswap); 560 561 /* 562 * If required, write synchronously, otherwise use 563 * delayed write. 564 */ 565 bwrite(bp); 566 return (0); 567 } 568 brelse(bp); 569 if (bpp != NULL) { 570 error = bread(ip->i_fd, ip->i_fs, lbn, (int)fs->fs_bsize, &nbp); 571 if (error) { 572 brelse(nbp); 573 return error; 574 } 575 *bpp = nbp; 576 } 577 return (0); 578 } 579