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 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 < UFS_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 UFS_NDADDR blocks are direct blocks 122 */ 123 124 if (lbn < UFS_NDADDR) { 125 nb = ufs_rw32(ip->i_ffs1_db[lbn], needswap); 126 if (nb != 0 && ip->i_ffs1_size >= 127 (uint64_t)lblktosize(fs, lbn + 1)) { 128 129 /* 130 * The block is an already-allocated direct block 131 * and the file already extends past this block, 132 * thus this must be a whole block. 133 * Just read the block (if requested). 134 */ 135 136 if (bpp != NULL) { 137 error = bread(&vp, lbn, fs->fs_bsize, NULL, 138 bpp); 139 if (error) { 140 brelse(*bpp, 0); 141 return (error); 142 } 143 } 144 return (0); 145 } 146 if (nb != 0) { 147 148 /* 149 * Consider need to reallocate a fragment. 150 */ 151 152 osize = fragroundup(fs, blkoff(fs, ip->i_ffs1_size)); 153 nsize = fragroundup(fs, size); 154 if (nsize <= osize) { 155 156 /* 157 * The existing block is already 158 * at least as big as we want. 159 * Just read the block (if requested). 160 */ 161 162 if (bpp != NULL) { 163 error = bread(&vp, lbn, osize, NULL, 164 bpp); 165 if (error) { 166 brelse(*bpp, 0); 167 return (error); 168 } 169 } 170 return 0; 171 } else { 172 warnx("need to ffs_realloccg; not supported!"); 173 abort(); 174 } 175 } else { 176 177 /* 178 * the block was not previously allocated, 179 * allocate a new block or fragment. 180 */ 181 182 if (ip->i_ffs1_size < (uint64_t)lblktosize(fs, lbn + 1)) 183 nsize = fragroundup(fs, size); 184 else 185 nsize = fs->fs_bsize; 186 error = ffs_alloc(ip, lbn, 187 ffs_blkpref_ufs1(ip, lbn, (int)lbn, 188 &ip->i_ffs1_db[0]), 189 nsize, &newb); 190 if (error) 191 return (error); 192 if (bpp != NULL) { 193 bp = getblk(&vp, lbn, nsize, 0, 0, 0); 194 bp->b_blkno = fsbtodb(fs, newb); 195 clrbuf(bp); 196 *bpp = bp; 197 } 198 } 199 ip->i_ffs1_db[lbn] = ufs_rw32((int32_t)newb, needswap); 200 return (0); 201 } 202 203 /* 204 * Determine the number of levels of indirection. 205 */ 206 207 pref = 0; 208 if ((error = ufs_getlbns(ip, lbn, indirs, &num)) != 0) 209 return (error); 210 211 if (num < 1) { 212 warnx("ffs_balloc: ufs_getlbns returned indirect block"); 213 abort(); 214 } 215 216 /* 217 * Fetch the first indirect block allocating if necessary. 218 */ 219 220 --num; 221 nb = ufs_rw32(ip->i_ffs1_ib[indirs[0].in_off], needswap); 222 allocib = NULL; 223 allocblk = allociblk; 224 if (nb == 0) { 225 pref = ffs_blkpref_ufs1(ip, lbn, 0, (int32_t *)0); 226 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 227 if (error) 228 return error; 229 nb = newb; 230 *allocblk++ = nb; 231 bp = getblk(&vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0, 0); 232 bp->b_blkno = fsbtodb(fs, nb); 233 clrbuf(bp); 234 /* 235 * Write synchronously so that indirect blocks 236 * never point at garbage. 237 */ 238 if ((error = bwrite(bp)) != 0) 239 return error; 240 allocib = &ip->i_ffs1_ib[indirs[0].in_off]; 241 *allocib = ufs_rw32((int32_t)nb, needswap); 242 } 243 244 /* 245 * Fetch through the indirect blocks, allocating as necessary. 246 */ 247 248 for (i = 1;;) { 249 error = bread(&vp, indirs[i].in_lbn, fs->fs_bsize, 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(&vp, 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(&vp, 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(&vp, 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 struct vnode vp = { ip->i_fd, ip->i_fs, NULL, 0 }; 344 345 lbn = lblkno(fs, offset); 346 size = blkoff(fs, offset) + bufsize; 347 if (bpp != NULL) { 348 *bpp = NULL; 349 } 350 351 assert(size <= fs->fs_bsize); 352 if (lbn < 0) 353 return (EFBIG); 354 355 /* 356 * If the next write will extend the file into a new block, 357 * and the file is currently composed of a fragment 358 * this fragment has to be extended to be a full block. 359 */ 360 361 lastlbn = lblkno(fs, ip->i_ffs2_size); 362 if (lastlbn < UFS_NDADDR && lastlbn < lbn) { 363 nb = lastlbn; 364 osize = blksize(fs, ip, nb); 365 if (osize < fs->fs_bsize && osize > 0) { 366 warnx("need to ffs_realloccg; not supported!"); 367 abort(); 368 } 369 } 370 371 /* 372 * The first UFS_NDADDR blocks are direct blocks 373 */ 374 375 if (lbn < UFS_NDADDR) { 376 nb = ufs_rw64(ip->i_ffs2_db[lbn], needswap); 377 if (nb != 0 && ip->i_ffs2_size >= 378 (uint64_t)lblktosize(fs, lbn + 1)) { 379 380 /* 381 * The block is an already-allocated direct block 382 * and the file already extends past this block, 383 * thus this must be a whole block. 384 * Just read the block (if requested). 385 */ 386 387 if (bpp != NULL) { 388 error = bread(&vp, lbn, fs->fs_bsize, NULL, 389 bpp); 390 if (error) { 391 brelse(*bpp, 0); 392 return (error); 393 } 394 } 395 return (0); 396 } 397 if (nb != 0) { 398 399 /* 400 * Consider need to reallocate a fragment. 401 */ 402 403 osize = fragroundup(fs, blkoff(fs, ip->i_ffs2_size)); 404 nsize = fragroundup(fs, size); 405 if (nsize <= osize) { 406 407 /* 408 * The existing block is already 409 * at least as big as we want. 410 * Just read the block (if requested). 411 */ 412 413 if (bpp != NULL) { 414 error = bread(&vp, lbn, osize, NULL, 415 bpp); 416 if (error) { 417 brelse(*bpp, 0); 418 return (error); 419 } 420 } 421 return 0; 422 } else { 423 warnx("need to ffs_realloccg; not supported!"); 424 abort(); 425 } 426 } else { 427 428 /* 429 * the block was not previously allocated, 430 * allocate a new block or fragment. 431 */ 432 433 if (ip->i_ffs2_size < (uint64_t)lblktosize(fs, lbn + 1)) 434 nsize = fragroundup(fs, size); 435 else 436 nsize = fs->fs_bsize; 437 error = ffs_alloc(ip, lbn, 438 ffs_blkpref_ufs2(ip, lbn, (int)lbn, 439 &ip->i_ffs2_db[0]), 440 nsize, &newb); 441 if (error) 442 return (error); 443 if (bpp != NULL) { 444 bp = getblk(&vp, lbn, nsize, 0, 0, 0); 445 bp->b_blkno = fsbtodb(fs, newb); 446 clrbuf(bp); 447 *bpp = bp; 448 } 449 } 450 ip->i_ffs2_db[lbn] = ufs_rw64(newb, needswap); 451 return (0); 452 } 453 454 /* 455 * Determine the number of levels of indirection. 456 */ 457 458 pref = 0; 459 if ((error = ufs_getlbns(ip, lbn, indirs, &num)) != 0) 460 return (error); 461 462 if (num < 1) { 463 warnx("ffs_balloc: ufs_getlbns returned indirect block"); 464 abort(); 465 } 466 467 /* 468 * Fetch the first indirect block allocating if necessary. 469 */ 470 471 --num; 472 nb = ufs_rw64(ip->i_ffs2_ib[indirs[0].in_off], needswap); 473 allocib = NULL; 474 allocblk = allociblk; 475 if (nb == 0) { 476 pref = ffs_blkpref_ufs2(ip, lbn, 0, (int64_t *)0); 477 error = ffs_alloc(ip, lbn, pref, (int)fs->fs_bsize, &newb); 478 if (error) 479 return error; 480 nb = newb; 481 *allocblk++ = nb; 482 bp = getblk(&vp, indirs[1].in_lbn, fs->fs_bsize, 0, 0, 0); 483 bp->b_blkno = fsbtodb(fs, nb); 484 clrbuf(bp); 485 /* 486 * Write synchronously so that indirect blocks 487 * never point at garbage. 488 */ 489 if ((error = bwrite(bp)) != 0) 490 return error; 491 allocib = &ip->i_ffs2_ib[indirs[0].in_off]; 492 *allocib = ufs_rw64(nb, needswap); 493 } 494 495 /* 496 * Fetch through the indirect blocks, allocating as necessary. 497 */ 498 499 for (i = 1;;) { 500 error = bread(&vp, indirs[i].in_lbn, fs->fs_bsize, 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(&vp, 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(&vp, 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(&vp, 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