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[UFS_NIADDR + 2]; 86 daddr_t newb, pref; 87 int32_t *bap; 88 int osize, nsize, num, i, error; 89 int32_t *allocblk, allociblk[UFS_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 < UFS_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 UFS_NDADDR blocks are direct blocks 121 */ 122 123 if (lbn < UFS_NDADDR) { 124 nb = ufs_rw32(ip->i_ffs1_db[lbn], needswap); 125 if (nb != 0 && ip->i_ffs1_size >= 126 (uint64_t)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(ip->i_devvp, lbn, fs->fs_bsize, 137 NULL, 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(ip->i_devvp, lbn, osize, 163 NULL, 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 < (uint64_t)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(ip->i_devvp, 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(ip->i_devvp, 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(ip->i_devvp, indirs[i].in_lbn, fs->fs_bsize, 249 NULL, &bp); 250 if (error) { 251 brelse(bp, 0); 252 return error; 253 } 254 bap = (int32_t *)bp->b_data; 255 nb = ufs_rw32(bap[indirs[i].in_off], needswap); 256 if (i == num) 257 break; 258 i++; 259 if (nb != 0) { 260 brelse(bp, 0); 261 continue; 262 } 263 if (pref == 0) 264 pref = ffs_blkpref_ufs1(ip, lbn, 0, (int32_t *)0); 265 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 266 if (error) { 267 brelse(bp, 0); 268 return error; 269 } 270 nb = newb; 271 *allocblk++ = nb; 272 nbp = getblk(ip->i_devvp, indirs[i].in_lbn, fs->fs_bsize, 0, 0, 0); 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, 0); 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, 0); 298 return error; 299 } 300 nb = newb; 301 *allocblk++ = nb; 302 if (bpp != NULL) { 303 nbp = getblk(ip->i_devvp, lbn, fs->fs_bsize, 0, 0, 0); 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, 0); 318 if (bpp != NULL) { 319 error = bread(ip->i_devvp, lbn, (int)fs->fs_bsize, NULL, &nbp); 320 if (error) { 321 brelse(nbp, 0); 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[UFS_NIADDR + 2]; 337 daddr_t newb, pref, nb; 338 int64_t *bap; 339 int osize, nsize, num, i, error; 340 int64_t *allocblk, allociblk[UFS_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 < UFS_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 UFS_NDADDR blocks are direct blocks 372 */ 373 374 if (lbn < UFS_NDADDR) { 375 nb = ufs_rw64(ip->i_ffs2_db[lbn], needswap); 376 if (nb != 0 && ip->i_ffs2_size >= 377 (uint64_t)lblktosize(fs, lbn + 1)) { 378 379 /* 380 * The block is an already-allocated direct block 381 * and the file already extends past this block, 382 * thus this must be a whole block. 383 * Just read the block (if requested). 384 */ 385 386 if (bpp != NULL) { 387 error = bread(ip->i_devvp, lbn, fs->fs_bsize, 388 NULL, bpp); 389 if (error) { 390 brelse(*bpp, 0); 391 return (error); 392 } 393 } 394 return (0); 395 } 396 if (nb != 0) { 397 398 /* 399 * Consider need to reallocate a fragment. 400 */ 401 402 osize = fragroundup(fs, blkoff(fs, ip->i_ffs2_size)); 403 nsize = fragroundup(fs, size); 404 if (nsize <= osize) { 405 406 /* 407 * The existing block is already 408 * at least as big as we want. 409 * Just read the block (if requested). 410 */ 411 412 if (bpp != NULL) { 413 error = bread(ip->i_devvp, lbn, osize, 414 NULL, bpp); 415 if (error) { 416 brelse(*bpp, 0); 417 return (error); 418 } 419 } 420 return 0; 421 } else { 422 warnx("need to ffs_realloccg; not supported!"); 423 abort(); 424 } 425 } else { 426 427 /* 428 * the block was not previously allocated, 429 * allocate a new block or fragment. 430 */ 431 432 if (ip->i_ffs2_size < (uint64_t)lblktosize(fs, lbn + 1)) 433 nsize = fragroundup(fs, size); 434 else 435 nsize = fs->fs_bsize; 436 error = ffs_alloc(ip, lbn, 437 ffs_blkpref_ufs2(ip, lbn, (int)lbn, 438 &ip->i_ffs2_db[0]), 439 nsize, &newb); 440 if (error) 441 return (error); 442 if (bpp != NULL) { 443 bp = getblk(ip->i_devvp, lbn, nsize, 0, 0, 0); 444 bp->b_blkno = fsbtodb(fs, newb); 445 clrbuf(bp); 446 *bpp = bp; 447 } 448 } 449 ip->i_ffs2_db[lbn] = ufs_rw64(newb, needswap); 450 return (0); 451 } 452 453 /* 454 * Determine the number of levels of indirection. 455 */ 456 457 pref = 0; 458 if ((error = ufs_getlbns(ip, lbn, indirs, &num)) != 0) 459 return (error); 460 461 if (num < 1) { 462 warnx("ffs_balloc: ufs_getlbns returned indirect block"); 463 abort(); 464 } 465 466 /* 467 * Fetch the first indirect block allocating if necessary. 468 */ 469 470 --num; 471 nb = ufs_rw64(ip->i_ffs2_ib[indirs[0].in_off], needswap); 472 allocib = NULL; 473 allocblk = allociblk; 474 if (nb == 0) { 475 pref = ffs_blkpref_ufs2(ip, lbn, 0, (int64_t *)0); 476 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 477 if (error) 478 return error; 479 nb = newb; 480 *allocblk++ = nb; 481 bp = getblk(ip->i_devvp, indirs[1].in_lbn, fs->fs_bsize, 0, 0, 0); 482 bp->b_blkno = fsbtodb(fs, nb); 483 clrbuf(bp); 484 /* 485 * Write synchronously so that indirect blocks 486 * never point at garbage. 487 */ 488 if ((error = bwrite(bp)) != 0) 489 return error; 490 allocib = &ip->i_ffs2_ib[indirs[0].in_off]; 491 *allocib = ufs_rw64(nb, needswap); 492 } 493 494 /* 495 * Fetch through the indirect blocks, allocating as necessary. 496 */ 497 498 for (i = 1;;) { 499 error = bread(ip->i_devvp, indirs[i].in_lbn, fs->fs_bsize, 500 NULL, &bp); 501 if (error) { 502 brelse(bp, 0); 503 return error; 504 } 505 bap = (int64_t *)bp->b_data; 506 nb = ufs_rw64(bap[indirs[i].in_off], needswap); 507 if (i == num) 508 break; 509 i++; 510 if (nb != 0) { 511 brelse(bp, 0); 512 continue; 513 } 514 if (pref == 0) 515 pref = ffs_blkpref_ufs2(ip, lbn, 0, (int64_t *)0); 516 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 517 if (error) { 518 brelse(bp, 0); 519 return error; 520 } 521 nb = newb; 522 *allocblk++ = nb; 523 nbp = getblk(ip->i_devvp, indirs[i].in_lbn, fs->fs_bsize, 0, 0, 0); 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, 0); 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, 0); 549 return error; 550 } 551 nb = newb; 552 *allocblk++ = nb; 553 if (bpp != NULL) { 554 nbp = getblk(ip->i_devvp, lbn, fs->fs_bsize, 0, 0, 0); 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, 0); 569 if (bpp != NULL) { 570 error = bread(ip->i_devvp, lbn, (int)fs->fs_bsize, NULL, &nbp); 571 if (error) { 572 brelse(nbp, 0); 573 return error; 574 } 575 *bpp = nbp; 576 } 577 return (0); 578 } 579