ext2_alloc.c revision 330897
1/*- 2 * modified for Lites 1.1 3 * 4 * Aug 1995, Godmar Back (gback@cs.utah.edu) 5 * University of Utah, Department of Computer Science 6 */ 7/*- 8 * SPDX-License-Identifier: BSD-3-Clause 9 * 10 * Copyright (c) 1982, 1986, 1989, 1993 11 * The Regents of the University of California. All rights reserved. 12 * 13 * Redistribution and use in source and binary forms, with or without 14 * modification, are permitted provided that the following conditions 15 * are met: 16 * 1. Redistributions of source code must retain the above copyright 17 * notice, this list of conditions and the following disclaimer. 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 4. Neither the name of the University nor the names of its contributors 22 * may be used to endorse or promote products derived from this software 23 * without specific prior written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 35 * SUCH DAMAGE. 36 * 37 * @(#)ffs_alloc.c 8.8 (Berkeley) 2/21/94 38 * $FreeBSD: stable/11/sys/fs/ext2fs/ext2_alloc.c 330897 2018-03-14 03:19:51Z eadler $ 39 */ 40 41#include <sys/param.h> 42#include <sys/systm.h> 43#include <sys/conf.h> 44#include <sys/vnode.h> 45#include <sys/stat.h> 46#include <sys/mount.h> 47#include <sys/sysctl.h> 48#include <sys/syslog.h> 49#include <sys/buf.h> 50#include <sys/endian.h> 51 52#include <fs/ext2fs/fs.h> 53#include <fs/ext2fs/inode.h> 54#include <fs/ext2fs/ext2_mount.h> 55#include <fs/ext2fs/ext2fs.h> 56#include <fs/ext2fs/ext2_extern.h> 57 58static daddr_t ext2_alloccg(struct inode *, int, daddr_t, int); 59static daddr_t ext2_clusteralloc(struct inode *, int, daddr_t, int); 60static u_long ext2_dirpref(struct inode *); 61static u_long ext2_hashalloc(struct inode *, int, long, int, 62 daddr_t (*)(struct inode *, int, daddr_t, 63 int)); 64static daddr_t ext2_nodealloccg(struct inode *, int, daddr_t, int); 65static daddr_t ext2_mapsearch(struct m_ext2fs *, char *, daddr_t); 66 67/* 68 * Allocate a block in the filesystem. 69 * 70 * A preference may be optionally specified. If a preference is given 71 * the following hierarchy is used to allocate a block: 72 * 1) allocate the requested block. 73 * 2) allocate a rotationally optimal block in the same cylinder. 74 * 3) allocate a block in the same cylinder group. 75 * 4) quadradically rehash into other cylinder groups, until an 76 * available block is located. 77 * If no block preference is given the following hierarchy is used 78 * to allocate a block: 79 * 1) allocate a block in the cylinder group that contains the 80 * inode for the file. 81 * 2) quadradically rehash into other cylinder groups, until an 82 * available block is located. 83 */ 84int 85ext2_alloc(struct inode *ip, daddr_t lbn, e4fs_daddr_t bpref, int size, 86 struct ucred *cred, e4fs_daddr_t *bnp) 87{ 88 struct m_ext2fs *fs; 89 struct ext2mount *ump; 90 int32_t bno; 91 int cg; 92 93 *bnp = 0; 94 fs = ip->i_e2fs; 95 ump = ip->i_ump; 96 mtx_assert(EXT2_MTX(ump), MA_OWNED); 97#ifdef INVARIANTS 98 if ((u_int)size > fs->e2fs_bsize || blkoff(fs, size) != 0) { 99 vn_printf(ip->i_devvp, "bsize = %lu, size = %d, fs = %s\n", 100 (long unsigned int)fs->e2fs_bsize, size, fs->e2fs_fsmnt); 101 panic("ext2_alloc: bad size"); 102 } 103 if (cred == NOCRED) 104 panic("ext2_alloc: missing credential"); 105#endif /* INVARIANTS */ 106 if (size == fs->e2fs_bsize && fs->e2fs->e2fs_fbcount == 0) 107 goto nospace; 108 if (cred->cr_uid != 0 && 109 fs->e2fs->e2fs_fbcount < fs->e2fs->e2fs_rbcount) 110 goto nospace; 111 if (bpref >= fs->e2fs->e2fs_bcount) 112 bpref = 0; 113 if (bpref == 0) 114 cg = ino_to_cg(fs, ip->i_number); 115 else 116 cg = dtog(fs, bpref); 117 bno = (daddr_t)ext2_hashalloc(ip, cg, bpref, fs->e2fs_bsize, 118 ext2_alloccg); 119 if (bno > 0) { 120 /* set next_alloc fields as done in block_getblk */ 121 ip->i_next_alloc_block = lbn; 122 ip->i_next_alloc_goal = bno; 123 124 ip->i_blocks += btodb(fs->e2fs_bsize); 125 ip->i_flag |= IN_CHANGE | IN_UPDATE; 126 *bnp = bno; 127 return (0); 128 } 129nospace: 130 EXT2_UNLOCK(ump); 131 ext2_fserr(fs, cred->cr_uid, "filesystem full"); 132 uprintf("\n%s: write failed, filesystem is full\n", fs->e2fs_fsmnt); 133 return (ENOSPC); 134} 135 136/* 137 * Allocate EA's block for inode. 138 */ 139daddr_t 140ext2_allocfacl(struct inode *ip) 141{ 142 struct m_ext2fs *fs; 143 daddr_t facl; 144 145 fs = ip->i_e2fs; 146 147 EXT2_LOCK(ip->i_ump); 148 facl = ext2_alloccg(ip, ino_to_cg(fs, ip->i_number), 0, fs->e2fs_bsize); 149 if (0 == facl) 150 EXT2_UNLOCK(ip->i_ump); 151 152 return (facl); 153} 154 155/* 156 * Reallocate a sequence of blocks into a contiguous sequence of blocks. 157 * 158 * The vnode and an array of buffer pointers for a range of sequential 159 * logical blocks to be made contiguous is given. The allocator attempts 160 * to find a range of sequential blocks starting as close as possible to 161 * an fs_rotdelay offset from the end of the allocation for the logical 162 * block immediately preceding the current range. If successful, the 163 * physical block numbers in the buffer pointers and in the inode are 164 * changed to reflect the new allocation. If unsuccessful, the allocation 165 * is left unchanged. The success in doing the reallocation is returned. 166 * Note that the error return is not reflected back to the user. Rather 167 * the previous block allocation will be used. 168 */ 169 170static SYSCTL_NODE(_vfs, OID_AUTO, ext2fs, CTLFLAG_RW, 0, "EXT2FS filesystem"); 171 172static int doasyncfree = 1; 173 174SYSCTL_INT(_vfs_ext2fs, OID_AUTO, doasyncfree, CTLFLAG_RW, &doasyncfree, 0, 175 "Use asychronous writes to update block pointers when freeing blocks"); 176 177static int doreallocblks = 0; 178 179SYSCTL_INT(_vfs_ext2fs, OID_AUTO, doreallocblks, CTLFLAG_RW, &doreallocblks, 0, ""); 180 181int 182ext2_reallocblks(struct vop_reallocblks_args *ap) 183{ 184 struct m_ext2fs *fs; 185 struct inode *ip; 186 struct vnode *vp; 187 struct buf *sbp, *ebp; 188 uint32_t *bap, *sbap, *ebap; 189 struct ext2mount *ump; 190 struct cluster_save *buflist; 191 struct indir start_ap[NIADDR + 1], end_ap[NIADDR + 1], *idp; 192 e2fs_lbn_t start_lbn, end_lbn; 193 int soff; 194 e2fs_daddr_t newblk, blkno; 195 int i, len, start_lvl, end_lvl, pref, ssize; 196 197 if (doreallocblks == 0) 198 return (ENOSPC); 199 200 vp = ap->a_vp; 201 ip = VTOI(vp); 202 fs = ip->i_e2fs; 203 ump = ip->i_ump; 204 205 if (fs->e2fs_contigsumsize <= 0) 206 return (ENOSPC); 207 208 buflist = ap->a_buflist; 209 len = buflist->bs_nchildren; 210 start_lbn = buflist->bs_children[0]->b_lblkno; 211 end_lbn = start_lbn + len - 1; 212#ifdef INVARIANTS 213 for (i = 1; i < len; i++) 214 if (buflist->bs_children[i]->b_lblkno != start_lbn + i) 215 panic("ext2_reallocblks: non-cluster"); 216#endif 217 /* 218 * If the cluster crosses the boundary for the first indirect 219 * block, leave space for the indirect block. Indirect blocks 220 * are initially laid out in a position after the last direct 221 * block. Block reallocation would usually destroy locality by 222 * moving the indirect block out of the way to make room for 223 * data blocks if we didn't compensate here. We should also do 224 * this for other indirect block boundaries, but it is only 225 * important for the first one. 226 */ 227 if (start_lbn < NDADDR && end_lbn >= NDADDR) 228 return (ENOSPC); 229 /* 230 * If the latest allocation is in a new cylinder group, assume that 231 * the filesystem has decided to move and do not force it back to 232 * the previous cylinder group. 233 */ 234 if (dtog(fs, dbtofsb(fs, buflist->bs_children[0]->b_blkno)) != 235 dtog(fs, dbtofsb(fs, buflist->bs_children[len - 1]->b_blkno))) 236 return (ENOSPC); 237 if (ext2_getlbns(vp, start_lbn, start_ap, &start_lvl) || 238 ext2_getlbns(vp, end_lbn, end_ap, &end_lvl)) 239 return (ENOSPC); 240 /* 241 * Get the starting offset and block map for the first block. 242 */ 243 if (start_lvl == 0) { 244 sbap = &ip->i_db[0]; 245 soff = start_lbn; 246 } else { 247 idp = &start_ap[start_lvl - 1]; 248 if (bread(vp, idp->in_lbn, (int)fs->e2fs_bsize, NOCRED, &sbp)) { 249 brelse(sbp); 250 return (ENOSPC); 251 } 252 sbap = (u_int *)sbp->b_data; 253 soff = idp->in_off; 254 } 255 /* 256 * If the block range spans two block maps, get the second map. 257 */ 258 ebap = NULL; 259 if (end_lvl == 0 || (idp = &end_ap[end_lvl - 1])->in_off + 1 >= len) { 260 ssize = len; 261 } else { 262#ifdef INVARIANTS 263 if (start_ap[start_lvl - 1].in_lbn == idp->in_lbn) 264 panic("ext2_reallocblks: start == end"); 265#endif 266 ssize = len - (idp->in_off + 1); 267 if (bread(vp, idp->in_lbn, (int)fs->e2fs_bsize, NOCRED, &ebp)) 268 goto fail; 269 ebap = (u_int *)ebp->b_data; 270 } 271 /* 272 * Find the preferred location for the cluster. 273 */ 274 EXT2_LOCK(ump); 275 pref = ext2_blkpref(ip, start_lbn, soff, sbap, 0); 276 /* 277 * Search the block map looking for an allocation of the desired size. 278 */ 279 if ((newblk = (e2fs_daddr_t)ext2_hashalloc(ip, dtog(fs, pref), pref, 280 len, ext2_clusteralloc)) == 0) { 281 EXT2_UNLOCK(ump); 282 goto fail; 283 } 284 /* 285 * We have found a new contiguous block. 286 * 287 * First we have to replace the old block pointers with the new 288 * block pointers in the inode and indirect blocks associated 289 * with the file. 290 */ 291#ifdef DEBUG 292 printf("realloc: ino %ju, lbns %jd-%jd\n\told:", 293 (uintmax_t)ip->i_number, (intmax_t)start_lbn, (intmax_t)end_lbn); 294#endif /* DEBUG */ 295 blkno = newblk; 296 for (bap = &sbap[soff], i = 0; i < len; i++, blkno += fs->e2fs_fpb) { 297 if (i == ssize) { 298 bap = ebap; 299 soff = -i; 300 } 301#ifdef INVARIANTS 302 if (buflist->bs_children[i]->b_blkno != fsbtodb(fs, *bap)) 303 panic("ext2_reallocblks: alloc mismatch"); 304#endif 305#ifdef DEBUG 306 printf(" %d,", *bap); 307#endif /* DEBUG */ 308 *bap++ = blkno; 309 } 310 /* 311 * Next we must write out the modified inode and indirect blocks. 312 * For strict correctness, the writes should be synchronous since 313 * the old block values may have been written to disk. In practise 314 * they are almost never written, but if we are concerned about 315 * strict correctness, the `doasyncfree' flag should be set to zero. 316 * 317 * The test on `doasyncfree' should be changed to test a flag 318 * that shows whether the associated buffers and inodes have 319 * been written. The flag should be set when the cluster is 320 * started and cleared whenever the buffer or inode is flushed. 321 * We can then check below to see if it is set, and do the 322 * synchronous write only when it has been cleared. 323 */ 324 if (sbap != &ip->i_db[0]) { 325 if (doasyncfree) 326 bdwrite(sbp); 327 else 328 bwrite(sbp); 329 } else { 330 ip->i_flag |= IN_CHANGE | IN_UPDATE; 331 if (!doasyncfree) 332 ext2_update(vp, 1); 333 } 334 if (ssize < len) { 335 if (doasyncfree) 336 bdwrite(ebp); 337 else 338 bwrite(ebp); 339 } 340 /* 341 * Last, free the old blocks and assign the new blocks to the buffers. 342 */ 343#ifdef DEBUG 344 printf("\n\tnew:"); 345#endif /* DEBUG */ 346 for (blkno = newblk, i = 0; i < len; i++, blkno += fs->e2fs_fpb) { 347 ext2_blkfree(ip, dbtofsb(fs, buflist->bs_children[i]->b_blkno), 348 fs->e2fs_bsize); 349 buflist->bs_children[i]->b_blkno = fsbtodb(fs, blkno); 350#ifdef DEBUG 351 printf(" %d,", blkno); 352#endif /* DEBUG */ 353 } 354#ifdef DEBUG 355 printf("\n"); 356#endif /* DEBUG */ 357 return (0); 358 359fail: 360 if (ssize < len) 361 brelse(ebp); 362 if (sbap != &ip->i_db[0]) 363 brelse(sbp); 364 return (ENOSPC); 365} 366 367/* 368 * Allocate an inode in the filesystem. 369 * 370 */ 371int 372ext2_valloc(struct vnode *pvp, int mode, struct ucred *cred, struct vnode **vpp) 373{ 374 struct timespec ts; 375 struct inode *pip; 376 struct m_ext2fs *fs; 377 struct inode *ip; 378 struct ext2mount *ump; 379 ino_t ino, ipref; 380 int i, error, cg; 381 382 *vpp = NULL; 383 pip = VTOI(pvp); 384 fs = pip->i_e2fs; 385 ump = pip->i_ump; 386 387 EXT2_LOCK(ump); 388 if (fs->e2fs->e2fs_ficount == 0) 389 goto noinodes; 390 /* 391 * If it is a directory then obtain a cylinder group based on 392 * ext2_dirpref else obtain it using ino_to_cg. The preferred inode is 393 * always the next inode. 394 */ 395 if ((mode & IFMT) == IFDIR) { 396 cg = ext2_dirpref(pip); 397 if (fs->e2fs_contigdirs[cg] < 255) 398 fs->e2fs_contigdirs[cg]++; 399 } else { 400 cg = ino_to_cg(fs, pip->i_number); 401 if (fs->e2fs_contigdirs[cg] > 0) 402 fs->e2fs_contigdirs[cg]--; 403 } 404 ipref = cg * fs->e2fs->e2fs_ipg + 1; 405 ino = (ino_t)ext2_hashalloc(pip, cg, (long)ipref, mode, ext2_nodealloccg); 406 407 if (ino == 0) 408 goto noinodes; 409 error = VFS_VGET(pvp->v_mount, ino, LK_EXCLUSIVE, vpp); 410 if (error) { 411 ext2_vfree(pvp, ino, mode); 412 return (error); 413 } 414 ip = VTOI(*vpp); 415 416 /* 417 * The question is whether using VGET was such good idea at all: 418 * Linux doesn't read the old inode in when it is allocating a 419 * new one. I will set at least i_size and i_blocks to zero. 420 */ 421 ip->i_flag = 0; 422 ip->i_size = 0; 423 ip->i_blocks = 0; 424 ip->i_mode = 0; 425 ip->i_flags = 0; 426 /* now we want to make sure that the block pointers are zeroed out */ 427 for (i = 0; i < NDADDR; i++) 428 ip->i_db[i] = 0; 429 for (i = 0; i < NIADDR; i++) 430 ip->i_ib[i] = 0; 431 432 /* 433 * Set up a new generation number for this inode. 434 * Avoid zero values. 435 */ 436 do { 437 ip->i_gen = arc4random(); 438 } while (ip->i_gen == 0); 439 440 vfs_timestamp(&ts); 441 ip->i_birthtime = ts.tv_sec; 442 ip->i_birthnsec = ts.tv_nsec; 443 444/* 445printf("ext2_valloc: allocated inode %d\n", ino); 446*/ 447 return (0); 448noinodes: 449 EXT2_UNLOCK(ump); 450 ext2_fserr(fs, cred->cr_uid, "out of inodes"); 451 uprintf("\n%s: create/symlink failed, no inodes free\n", fs->e2fs_fsmnt); 452 return (ENOSPC); 453} 454 455/* 456 * Find a cylinder to place a directory. 457 * 458 * The policy implemented by this algorithm is to allocate a 459 * directory inode in the same cylinder group as its parent 460 * directory, but also to reserve space for its files inodes 461 * and data. Restrict the number of directories which may be 462 * allocated one after another in the same cylinder group 463 * without intervening allocation of files. 464 * 465 * If we allocate a first level directory then force allocation 466 * in another cylinder group. 467 * 468 */ 469static u_long 470ext2_dirpref(struct inode *pip) 471{ 472 struct m_ext2fs *fs; 473 int cg, prefcg, cgsize; 474 u_int avgifree, avgbfree, avgndir, curdirsize; 475 u_int minifree, minbfree, maxndir; 476 u_int mincg, minndir; 477 u_int dirsize, maxcontigdirs; 478 479 mtx_assert(EXT2_MTX(pip->i_ump), MA_OWNED); 480 fs = pip->i_e2fs; 481 482 avgifree = fs->e2fs->e2fs_ficount / fs->e2fs_gcount; 483 avgbfree = fs->e2fs->e2fs_fbcount / fs->e2fs_gcount; 484 avgndir = fs->e2fs_total_dir / fs->e2fs_gcount; 485 486 /* 487 * Force allocation in another cg if creating a first level dir. 488 */ 489 ASSERT_VOP_LOCKED(ITOV(pip), "ext2fs_dirpref"); 490 if (ITOV(pip)->v_vflag & VV_ROOT) { 491 prefcg = arc4random() % fs->e2fs_gcount; 492 mincg = prefcg; 493 minndir = fs->e2fs_ipg; 494 for (cg = prefcg; cg < fs->e2fs_gcount; cg++) 495 if (fs->e2fs_gd[cg].ext2bgd_ndirs < minndir && 496 fs->e2fs_gd[cg].ext2bgd_nifree >= avgifree && 497 fs->e2fs_gd[cg].ext2bgd_nbfree >= avgbfree) { 498 mincg = cg; 499 minndir = fs->e2fs_gd[cg].ext2bgd_ndirs; 500 } 501 for (cg = 0; cg < prefcg; cg++) 502 if (fs->e2fs_gd[cg].ext2bgd_ndirs < minndir && 503 fs->e2fs_gd[cg].ext2bgd_nifree >= avgifree && 504 fs->e2fs_gd[cg].ext2bgd_nbfree >= avgbfree) { 505 mincg = cg; 506 minndir = fs->e2fs_gd[cg].ext2bgd_ndirs; 507 } 508 return (mincg); 509 } 510 /* 511 * Count various limits which used for 512 * optimal allocation of a directory inode. 513 */ 514 maxndir = min(avgndir + fs->e2fs_ipg / 16, fs->e2fs_ipg); 515 minifree = avgifree - avgifree / 4; 516 if (minifree < 1) 517 minifree = 1; 518 minbfree = avgbfree - avgbfree / 4; 519 if (minbfree < 1) 520 minbfree = 1; 521 cgsize = fs->e2fs_fsize * fs->e2fs_fpg; 522 dirsize = AVGDIRSIZE; 523 curdirsize = avgndir ? (cgsize - avgbfree * fs->e2fs_bsize) / avgndir : 0; 524 if (dirsize < curdirsize) 525 dirsize = curdirsize; 526 maxcontigdirs = min((avgbfree * fs->e2fs_bsize) / dirsize, 255); 527 maxcontigdirs = min(maxcontigdirs, fs->e2fs_ipg / AFPDIR); 528 if (maxcontigdirs == 0) 529 maxcontigdirs = 1; 530 531 /* 532 * Limit number of dirs in one cg and reserve space for 533 * regular files, but only if we have no deficit in 534 * inodes or space. 535 */ 536 prefcg = ino_to_cg(fs, pip->i_number); 537 for (cg = prefcg; cg < fs->e2fs_gcount; cg++) 538 if (fs->e2fs_gd[cg].ext2bgd_ndirs < maxndir && 539 fs->e2fs_gd[cg].ext2bgd_nifree >= minifree && 540 fs->e2fs_gd[cg].ext2bgd_nbfree >= minbfree) { 541 if (fs->e2fs_contigdirs[cg] < maxcontigdirs) 542 return (cg); 543 } 544 for (cg = 0; cg < prefcg; cg++) 545 if (fs->e2fs_gd[cg].ext2bgd_ndirs < maxndir && 546 fs->e2fs_gd[cg].ext2bgd_nifree >= minifree && 547 fs->e2fs_gd[cg].ext2bgd_nbfree >= minbfree) { 548 if (fs->e2fs_contigdirs[cg] < maxcontigdirs) 549 return (cg); 550 } 551 /* 552 * This is a backstop when we have deficit in space. 553 */ 554 for (cg = prefcg; cg < fs->e2fs_gcount; cg++) 555 if (fs->e2fs_gd[cg].ext2bgd_nifree >= avgifree) 556 return (cg); 557 for (cg = 0; cg < prefcg; cg++) 558 if (fs->e2fs_gd[cg].ext2bgd_nifree >= avgifree) 559 break; 560 return (cg); 561} 562 563/* 564 * Select the desired position for the next block in a file. 565 * 566 * we try to mimic what Remy does in inode_getblk/block_getblk 567 * 568 * we note: blocknr == 0 means that we're about to allocate either 569 * a direct block or a pointer block at the first level of indirection 570 * (In other words, stuff that will go in i_db[] or i_ib[]) 571 * 572 * blocknr != 0 means that we're allocating a block that is none 573 * of the above. Then, blocknr tells us the number of the block 574 * that will hold the pointer 575 */ 576e4fs_daddr_t 577ext2_blkpref(struct inode *ip, e2fs_lbn_t lbn, int indx, e2fs_daddr_t *bap, 578 e2fs_daddr_t blocknr) 579{ 580 int tmp; 581 582 mtx_assert(EXT2_MTX(ip->i_ump), MA_OWNED); 583 584 /* 585 * If the next block is actually what we thought it is, then set the 586 * goal to what we thought it should be. 587 */ 588 if (ip->i_next_alloc_block == lbn && ip->i_next_alloc_goal != 0) 589 return ip->i_next_alloc_goal; 590 591 /* 592 * Now check whether we were provided with an array that basically 593 * tells us previous blocks to which we want to stay close. 594 */ 595 if (bap) 596 for (tmp = indx - 1; tmp >= 0; tmp--) 597 if (bap[tmp]) 598 return bap[tmp]; 599 600 /* 601 * Else lets fall back to the blocknr or, if there is none, follow 602 * the rule that a block should be allocated near its inode. 603 */ 604 return blocknr ? blocknr : 605 (e2fs_daddr_t)(ip->i_block_group * 606 EXT2_BLOCKS_PER_GROUP(ip->i_e2fs)) + 607 ip->i_e2fs->e2fs->e2fs_first_dblock; 608} 609 610/* 611 * Implement the cylinder overflow algorithm. 612 * 613 * The policy implemented by this algorithm is: 614 * 1) allocate the block in its requested cylinder group. 615 * 2) quadradically rehash on the cylinder group number. 616 * 3) brute force search for a free block. 617 */ 618static u_long 619ext2_hashalloc(struct inode *ip, int cg, long pref, int size, 620 daddr_t (*allocator) (struct inode *, int, daddr_t, int)) 621{ 622 struct m_ext2fs *fs; 623 ino_t result; 624 int i, icg = cg; 625 626 mtx_assert(EXT2_MTX(ip->i_ump), MA_OWNED); 627 fs = ip->i_e2fs; 628 /* 629 * 1: preferred cylinder group 630 */ 631 result = (*allocator)(ip, cg, pref, size); 632 if (result) 633 return (result); 634 /* 635 * 2: quadratic rehash 636 */ 637 for (i = 1; i < fs->e2fs_gcount; i *= 2) { 638 cg += i; 639 if (cg >= fs->e2fs_gcount) 640 cg -= fs->e2fs_gcount; 641 result = (*allocator)(ip, cg, 0, size); 642 if (result) 643 return (result); 644 } 645 /* 646 * 3: brute force search 647 * Note that we start at i == 2, since 0 was checked initially, 648 * and 1 is always checked in the quadratic rehash. 649 */ 650 cg = (icg + 2) % fs->e2fs_gcount; 651 for (i = 2; i < fs->e2fs_gcount; i++) { 652 result = (*allocator)(ip, cg, 0, size); 653 if (result) 654 return (result); 655 cg++; 656 if (cg == fs->e2fs_gcount) 657 cg = 0; 658 } 659 return (0); 660} 661 662static unsigned long 663ext2_cg_num_gdb(struct m_ext2fs *fs, int cg) 664{ 665 int gd_per_block, metagroup, first, last; 666 667 gd_per_block = fs->e2fs_bsize / sizeof(struct ext2_gd); 668 metagroup = cg / gd_per_block; 669 first = metagroup * gd_per_block; 670 last = first + gd_per_block - 1; 671 672 if (!EXT2_HAS_INCOMPAT_FEATURE(fs, EXT2F_INCOMPAT_META_BG) || 673 metagroup < fs->e2fs->e3fs_first_meta_bg) { 674 if (!ext2_cg_has_sb(fs, cg)) 675 return (0); 676 if (EXT2_HAS_INCOMPAT_FEATURE(fs, EXT2F_INCOMPAT_META_BG)) 677 return (fs->e2fs->e3fs_first_meta_bg); 678 return (fs->e2fs_gdbcount); 679 } 680 681 if (cg == first || cg == first + 1 || cg == last) 682 return (1); 683 return (0); 684 685} 686 687static int 688ext2_num_base_meta_blocks(struct m_ext2fs *fs, int cg) 689{ 690 int num, gd_per_block; 691 692 gd_per_block = fs->e2fs_bsize / sizeof(struct ext2_gd); 693 num = ext2_cg_has_sb(fs, cg); 694 695 if (!EXT2_HAS_INCOMPAT_FEATURE(fs, EXT2F_INCOMPAT_META_BG) || 696 cg < fs->e2fs->e3fs_first_meta_bg * gd_per_block) { 697 if (num) { 698 num += ext2_cg_num_gdb(fs, cg); 699 num += fs->e2fs->e2fs_reserved_ngdb; 700 } 701 } else { 702 num += ext2_cg_num_gdb(fs, cg); 703 } 704 705 return (num); 706} 707 708static int 709ext2_get_cg_number(struct m_ext2fs *fs, daddr_t blk) 710{ 711 int cg; 712 713 if (fs->e2fs->e2fs_bpg == fs->e2fs_bsize * 8) 714 cg = (blk - fs->e2fs->e2fs_first_dblock) / (fs->e2fs_bsize * 8); 715 else 716 cg = blk - fs->e2fs->e2fs_first_dblock; 717 718 return (cg); 719} 720 721static void 722ext2_mark_bitmap_end(int start_bit, int end_bit, char *bitmap) 723{ 724 int i; 725 726 if (start_bit >= end_bit) 727 return; 728 729 for (i = start_bit; i < ((start_bit + 7) & ~7UL); i++) 730 setbit(bitmap, i); 731 if (i < end_bit) 732 memset(bitmap + (i >> 3), 0xff, (end_bit - i) >> 3); 733} 734 735static int 736ext2_cg_block_bitmap_init(struct m_ext2fs *fs, int cg, struct buf *bp) 737{ 738 int bit, bit_max, inodes_per_block; 739 uint32_t start, tmp; 740 741 if (!EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM) || 742 !(fs->e2fs_gd[cg].ext4bgd_flags & EXT2_BG_BLOCK_UNINIT)) 743 return (0); 744 745 memset(bp->b_data, 0, fs->e2fs_bsize); 746 747 bit_max = ext2_num_base_meta_blocks(fs, cg); 748 if ((bit_max >> 3) >= fs->e2fs_bsize) 749 return (EINVAL); 750 751 for (bit = 0; bit < bit_max; bit++) 752 setbit(bp->b_data, bit); 753 754 start = cg * fs->e2fs->e2fs_bpg + fs->e2fs->e2fs_first_dblock; 755 756 /* Set bits for block and inode bitmaps, and inode table */ 757 tmp = fs->e2fs_gd[cg].ext2bgd_b_bitmap; 758 if (!EXT2_HAS_INCOMPAT_FEATURE(fs, EXT2F_INCOMPAT_FLEX_BG) || 759 tmp == ext2_get_cg_number(fs, cg)) 760 setbit(bp->b_data, tmp - start); 761 762 tmp = fs->e2fs_gd[cg].ext2bgd_i_bitmap; 763 if (!EXT2_HAS_INCOMPAT_FEATURE(fs, EXT2F_INCOMPAT_FLEX_BG) || 764 tmp == ext2_get_cg_number(fs, cg)) 765 setbit(bp->b_data, tmp - start); 766 767 tmp = fs->e2fs_gd[cg].ext2bgd_i_tables; 768 inodes_per_block = fs->e2fs_bsize/EXT2_INODE_SIZE(fs); 769 while( tmp < fs->e2fs_gd[cg].ext2bgd_i_tables + 770 fs->e2fs->e2fs_ipg / inodes_per_block ) { 771 if (!EXT2_HAS_INCOMPAT_FEATURE(fs, EXT2F_INCOMPAT_FLEX_BG) || 772 tmp == ext2_get_cg_number(fs, cg)) 773 setbit(bp->b_data, tmp - start); 774 tmp++; 775 } 776 777 /* 778 * Also if the number of blocks within the group is less than 779 * the blocksize * 8 ( which is the size of bitmap ), set rest 780 * of the block bitmap to 1 781 */ 782 ext2_mark_bitmap_end(fs->e2fs->e2fs_bpg, fs->e2fs_bsize * 8, 783 bp->b_data); 784 785 /* Clean the flag */ 786 fs->e2fs_gd[cg].ext4bgd_flags &= ~EXT2_BG_BLOCK_UNINIT; 787 788 return (0); 789} 790 791/* 792 * Determine whether a block can be allocated. 793 * 794 * Check to see if a block of the appropriate size is available, 795 * and if it is, allocate it. 796 */ 797static daddr_t 798ext2_alloccg(struct inode *ip, int cg, daddr_t bpref, int size) 799{ 800 struct m_ext2fs *fs; 801 struct buf *bp; 802 struct ext2mount *ump; 803 daddr_t bno, runstart, runlen; 804 int bit, loc, end, error, start; 805 char *bbp; 806 /* XXX ondisk32 */ 807 fs = ip->i_e2fs; 808 ump = ip->i_ump; 809 if (fs->e2fs_gd[cg].ext2bgd_nbfree == 0) 810 return (0); 811 EXT2_UNLOCK(ump); 812 error = bread(ip->i_devvp, fsbtodb(fs, 813 fs->e2fs_gd[cg].ext2bgd_b_bitmap), 814 (int)fs->e2fs_bsize, NOCRED, &bp); 815 if (error) { 816 brelse(bp); 817 EXT2_LOCK(ump); 818 return (0); 819 } 820 if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM)) { 821 error = ext2_cg_block_bitmap_init(fs, cg, bp); 822 if (error) { 823 brelse(bp); 824 EXT2_LOCK(ump); 825 return (0); 826 } 827 } 828 if (fs->e2fs_gd[cg].ext2bgd_nbfree == 0) { 829 /* 830 * Another thread allocated the last block in this 831 * group while we were waiting for the buffer. 832 */ 833 brelse(bp); 834 EXT2_LOCK(ump); 835 return (0); 836 } 837 bbp = (char *)bp->b_data; 838 839 if (dtog(fs, bpref) != cg) 840 bpref = 0; 841 if (bpref != 0) { 842 bpref = dtogd(fs, bpref); 843 /* 844 * if the requested block is available, use it 845 */ 846 if (isclr(bbp, bpref)) { 847 bno = bpref; 848 goto gotit; 849 } 850 } 851 /* 852 * no blocks in the requested cylinder, so take next 853 * available one in this cylinder group. 854 * first try to get 8 contigous blocks, then fall back to a single 855 * block. 856 */ 857 if (bpref) 858 start = dtogd(fs, bpref) / NBBY; 859 else 860 start = 0; 861 end = howmany(fs->e2fs->e2fs_fpg, NBBY) - start; 862retry: 863 runlen = 0; 864 runstart = 0; 865 for (loc = start; loc < end; loc++) { 866 if (bbp[loc] == (char)0xff) { 867 runlen = 0; 868 continue; 869 } 870 871 /* Start of a run, find the number of high clear bits. */ 872 if (runlen == 0) { 873 bit = fls(bbp[loc]); 874 runlen = NBBY - bit; 875 runstart = loc * NBBY + bit; 876 } else if (bbp[loc] == 0) { 877 /* Continue a run. */ 878 runlen += NBBY; 879 } else { 880 /* 881 * Finish the current run. If it isn't long 882 * enough, start a new one. 883 */ 884 bit = ffs(bbp[loc]) - 1; 885 runlen += bit; 886 if (runlen >= 8) { 887 bno = runstart; 888 goto gotit; 889 } 890 891 /* Run was too short, start a new one. */ 892 bit = fls(bbp[loc]); 893 runlen = NBBY - bit; 894 runstart = loc * NBBY + bit; 895 } 896 897 /* If the current run is long enough, use it. */ 898 if (runlen >= 8) { 899 bno = runstart; 900 goto gotit; 901 } 902 } 903 if (start != 0) { 904 end = start; 905 start = 0; 906 goto retry; 907 } 908 bno = ext2_mapsearch(fs, bbp, bpref); 909 if (bno < 0) { 910 brelse(bp); 911 EXT2_LOCK(ump); 912 return (0); 913 } 914gotit: 915#ifdef INVARIANTS 916 if (isset(bbp, bno)) { 917 printf("ext2fs_alloccgblk: cg=%d bno=%jd fs=%s\n", 918 cg, (intmax_t)bno, fs->e2fs_fsmnt); 919 panic("ext2fs_alloccg: dup alloc"); 920 } 921#endif 922 setbit(bbp, bno); 923 EXT2_LOCK(ump); 924 ext2_clusteracct(fs, bbp, cg, bno, -1); 925 fs->e2fs->e2fs_fbcount--; 926 fs->e2fs_gd[cg].ext2bgd_nbfree--; 927 fs->e2fs_fmod = 1; 928 EXT2_UNLOCK(ump); 929 bdwrite(bp); 930 return (cg * fs->e2fs->e2fs_fpg + fs->e2fs->e2fs_first_dblock + bno); 931} 932 933/* 934 * Determine whether a cluster can be allocated. 935 */ 936static daddr_t 937ext2_clusteralloc(struct inode *ip, int cg, daddr_t bpref, int len) 938{ 939 struct m_ext2fs *fs; 940 struct ext2mount *ump; 941 struct buf *bp; 942 char *bbp; 943 int bit, error, got, i, loc, run; 944 int32_t *lp; 945 daddr_t bno; 946 947 fs = ip->i_e2fs; 948 ump = ip->i_ump; 949 950 if (fs->e2fs_maxcluster[cg] < len) 951 return (0); 952 953 EXT2_UNLOCK(ump); 954 error = bread(ip->i_devvp, 955 fsbtodb(fs, fs->e2fs_gd[cg].ext2bgd_b_bitmap), 956 (int)fs->e2fs_bsize, NOCRED, &bp); 957 if (error) 958 goto fail_lock; 959 960 bbp = (char *)bp->b_data; 961 EXT2_LOCK(ump); 962 /* 963 * Check to see if a cluster of the needed size (or bigger) is 964 * available in this cylinder group. 965 */ 966 lp = &fs->e2fs_clustersum[cg].cs_sum[len]; 967 for (i = len; i <= fs->e2fs_contigsumsize; i++) 968 if (*lp++ > 0) 969 break; 970 if (i > fs->e2fs_contigsumsize) { 971 /* 972 * Update the cluster summary information to reflect 973 * the true maximum-sized cluster so that future cluster 974 * allocation requests can avoid reading the bitmap only 975 * to find no cluster. 976 */ 977 lp = &fs->e2fs_clustersum[cg].cs_sum[len - 1]; 978 for (i = len - 1; i > 0; i--) 979 if (*lp-- > 0) 980 break; 981 fs->e2fs_maxcluster[cg] = i; 982 goto fail; 983 } 984 EXT2_UNLOCK(ump); 985 986 /* Search the bitmap to find a big enough cluster like in FFS. */ 987 if (dtog(fs, bpref) != cg) 988 bpref = 0; 989 if (bpref != 0) 990 bpref = dtogd(fs, bpref); 991 loc = bpref / NBBY; 992 bit = 1 << (bpref % NBBY); 993 for (run = 0, got = bpref; got < fs->e2fs->e2fs_fpg; got++) { 994 if ((bbp[loc] & bit) != 0) 995 run = 0; 996 else { 997 run++; 998 if (run == len) 999 break; 1000 } 1001 if ((got & (NBBY - 1)) != (NBBY - 1)) 1002 bit <<= 1; 1003 else { 1004 loc++; 1005 bit = 1; 1006 } 1007 } 1008 1009 if (got >= fs->e2fs->e2fs_fpg) 1010 goto fail_lock; 1011 1012 /* Allocate the cluster that we found. */ 1013 for (i = 1; i < len; i++) 1014 if (!isclr(bbp, got - run + i)) 1015 panic("ext2_clusteralloc: map mismatch"); 1016 1017 bno = got - run + 1; 1018 if (bno >= fs->e2fs->e2fs_fpg) 1019 panic("ext2_clusteralloc: allocated out of group"); 1020 1021 EXT2_LOCK(ump); 1022 for (i = 0; i < len; i += fs->e2fs_fpb) { 1023 setbit(bbp, bno + i); 1024 ext2_clusteracct(fs, bbp, cg, bno + i, -1); 1025 fs->e2fs->e2fs_fbcount--; 1026 fs->e2fs_gd[cg].ext2bgd_nbfree--; 1027 } 1028 fs->e2fs_fmod = 1; 1029 EXT2_UNLOCK(ump); 1030 1031 bdwrite(bp); 1032 return (cg * fs->e2fs->e2fs_fpg + fs->e2fs->e2fs_first_dblock + bno); 1033 1034fail_lock: 1035 EXT2_LOCK(ump); 1036fail: 1037 brelse(bp); 1038 return (0); 1039} 1040 1041static int 1042ext2_zero_inode_table(struct inode *ip, int cg) 1043{ 1044 struct m_ext2fs *fs; 1045 struct buf *bp; 1046 int i, all_blks, used_blks; 1047 1048 fs = ip->i_e2fs; 1049 1050 if (fs->e2fs_gd[cg].ext4bgd_flags & EXT2_BG_INODE_ZEROED) 1051 return (0); 1052 1053 all_blks = fs->e2fs->e2fs_inode_size * fs->e2fs->e2fs_ipg / 1054 fs->e2fs_bsize; 1055 1056 used_blks = howmany(fs->e2fs->e2fs_ipg - 1057 fs->e2fs_gd[cg].ext4bgd_i_unused, 1058 fs->e2fs_bsize / EXT2_INODE_SIZE(fs)); 1059 1060 for (i = 0; i < all_blks - used_blks; i++) { 1061 bp = getblk(ip->i_devvp, fsbtodb(fs, 1062 fs->e2fs_gd[cg].ext2bgd_i_tables + used_blks + i), 1063 fs->e2fs_bsize, 0, 0, 0); 1064 if (!bp) 1065 return (EIO); 1066 1067 vfs_bio_bzero_buf(bp, 0, fs->e2fs_bsize); 1068 bawrite(bp); 1069 } 1070 1071 fs->e2fs_gd[cg].ext4bgd_flags |= EXT2_BG_INODE_ZEROED; 1072 1073 return (0); 1074} 1075 1076/* 1077 * Determine whether an inode can be allocated. 1078 * 1079 * Check to see if an inode is available, and if it is, 1080 * allocate it using tode in the specified cylinder group. 1081 */ 1082static daddr_t 1083ext2_nodealloccg(struct inode *ip, int cg, daddr_t ipref, int mode) 1084{ 1085 struct m_ext2fs *fs; 1086 struct buf *bp; 1087 struct ext2mount *ump; 1088 int error, start, len; 1089 char *ibp, *loc; 1090 1091 ipref--; /* to avoid a lot of (ipref -1) */ 1092 if (ipref == -1) 1093 ipref = 0; 1094 fs = ip->i_e2fs; 1095 ump = ip->i_ump; 1096 if (fs->e2fs_gd[cg].ext2bgd_nifree == 0) 1097 return (0); 1098 EXT2_UNLOCK(ump); 1099 error = bread(ip->i_devvp, fsbtodb(fs, 1100 fs->e2fs_gd[cg].ext2bgd_i_bitmap), 1101 (int)fs->e2fs_bsize, NOCRED, &bp); 1102 if (error) { 1103 brelse(bp); 1104 EXT2_LOCK(ump); 1105 return (0); 1106 } 1107 if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM)) { 1108 if (fs->e2fs_gd[cg].ext4bgd_flags & EXT2_BG_INODE_UNINIT) { 1109 memset(bp->b_data, 0, fs->e2fs_bsize); 1110 fs->e2fs_gd[cg].ext4bgd_flags &= ~EXT2_BG_INODE_UNINIT; 1111 } 1112 error = ext2_zero_inode_table(ip, cg); 1113 if (error) { 1114 brelse(bp); 1115 EXT2_LOCK(ump); 1116 return (0); 1117 } 1118 } 1119 if (fs->e2fs_gd[cg].ext2bgd_nifree == 0) { 1120 /* 1121 * Another thread allocated the last i-node in this 1122 * group while we were waiting for the buffer. 1123 */ 1124 brelse(bp); 1125 EXT2_LOCK(ump); 1126 return (0); 1127 } 1128 ibp = (char *)bp->b_data; 1129 if (ipref) { 1130 ipref %= fs->e2fs->e2fs_ipg; 1131 if (isclr(ibp, ipref)) 1132 goto gotit; 1133 } 1134 start = ipref / NBBY; 1135 len = howmany(fs->e2fs->e2fs_ipg - ipref, NBBY); 1136 loc = memcchr(&ibp[start], 0xff, len); 1137 if (loc == NULL) { 1138 len = start + 1; 1139 start = 0; 1140 loc = memcchr(&ibp[start], 0xff, len); 1141 if (loc == NULL) { 1142 printf("cg = %d, ipref = %lld, fs = %s\n", 1143 cg, (long long)ipref, fs->e2fs_fsmnt); 1144 panic("ext2fs_nodealloccg: map corrupted"); 1145 /* NOTREACHED */ 1146 } 1147 } 1148 ipref = (loc - ibp) * NBBY + ffs(~*loc) - 1; 1149gotit: 1150 setbit(ibp, ipref); 1151 EXT2_LOCK(ump); 1152 fs->e2fs_gd[cg].ext2bgd_nifree--; 1153 if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM)) 1154 fs->e2fs_gd[cg].ext4bgd_i_unused--; 1155 fs->e2fs->e2fs_ficount--; 1156 fs->e2fs_fmod = 1; 1157 if ((mode & IFMT) == IFDIR) { 1158 fs->e2fs_gd[cg].ext2bgd_ndirs++; 1159 fs->e2fs_total_dir++; 1160 } 1161 EXT2_UNLOCK(ump); 1162 bdwrite(bp); 1163 return (cg * fs->e2fs->e2fs_ipg + ipref + 1); 1164} 1165 1166/* 1167 * Free a block or fragment. 1168 * 1169 */ 1170void 1171ext2_blkfree(struct inode *ip, e4fs_daddr_t bno, long size) 1172{ 1173 struct m_ext2fs *fs; 1174 struct buf *bp; 1175 struct ext2mount *ump; 1176 int cg, error; 1177 char *bbp; 1178 1179 fs = ip->i_e2fs; 1180 ump = ip->i_ump; 1181 cg = dtog(fs, bno); 1182 if ((u_int)bno >= fs->e2fs->e2fs_bcount) { 1183 printf("bad block %lld, ino %ju\n", (long long)bno, 1184 (uintmax_t)ip->i_number); 1185 ext2_fserr(fs, ip->i_uid, "bad block"); 1186 return; 1187 } 1188 error = bread(ip->i_devvp, 1189 fsbtodb(fs, fs->e2fs_gd[cg].ext2bgd_b_bitmap), 1190 (int)fs->e2fs_bsize, NOCRED, &bp); 1191 if (error) { 1192 brelse(bp); 1193 return; 1194 } 1195 bbp = (char *)bp->b_data; 1196 bno = dtogd(fs, bno); 1197 if (isclr(bbp, bno)) { 1198 printf("block = %lld, fs = %s\n", 1199 (long long)bno, fs->e2fs_fsmnt); 1200 panic("ext2_blkfree: freeing free block"); 1201 } 1202 clrbit(bbp, bno); 1203 EXT2_LOCK(ump); 1204 ext2_clusteracct(fs, bbp, cg, bno, 1); 1205 fs->e2fs->e2fs_fbcount++; 1206 fs->e2fs_gd[cg].ext2bgd_nbfree++; 1207 fs->e2fs_fmod = 1; 1208 EXT2_UNLOCK(ump); 1209 bdwrite(bp); 1210} 1211 1212/* 1213 * Free an inode. 1214 * 1215 */ 1216int 1217ext2_vfree(struct vnode *pvp, ino_t ino, int mode) 1218{ 1219 struct m_ext2fs *fs; 1220 struct inode *pip; 1221 struct buf *bp; 1222 struct ext2mount *ump; 1223 int error, cg; 1224 char *ibp; 1225 1226 pip = VTOI(pvp); 1227 fs = pip->i_e2fs; 1228 ump = pip->i_ump; 1229 if ((u_int)ino > fs->e2fs_ipg * fs->e2fs_gcount) 1230 panic("ext2_vfree: range: devvp = %p, ino = %ju, fs = %s", 1231 pip->i_devvp, (uintmax_t)ino, fs->e2fs_fsmnt); 1232 1233 cg = ino_to_cg(fs, ino); 1234 error = bread(pip->i_devvp, 1235 fsbtodb(fs, fs->e2fs_gd[cg].ext2bgd_i_bitmap), 1236 (int)fs->e2fs_bsize, NOCRED, &bp); 1237 if (error) { 1238 brelse(bp); 1239 return (0); 1240 } 1241 ibp = (char *)bp->b_data; 1242 ino = (ino - 1) % fs->e2fs->e2fs_ipg; 1243 if (isclr(ibp, ino)) { 1244 printf("ino = %llu, fs = %s\n", 1245 (unsigned long long)ino, fs->e2fs_fsmnt); 1246 if (fs->e2fs_ronly == 0) 1247 panic("ext2_vfree: freeing free inode"); 1248 } 1249 clrbit(ibp, ino); 1250 EXT2_LOCK(ump); 1251 fs->e2fs->e2fs_ficount++; 1252 fs->e2fs_gd[cg].ext2bgd_nifree++; 1253 if (EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_GDT_CSUM)) 1254 fs->e2fs_gd[cg].ext4bgd_i_unused++; 1255 if ((mode & IFMT) == IFDIR) { 1256 fs->e2fs_gd[cg].ext2bgd_ndirs--; 1257 fs->e2fs_total_dir--; 1258 } 1259 fs->e2fs_fmod = 1; 1260 EXT2_UNLOCK(ump); 1261 bdwrite(bp); 1262 return (0); 1263} 1264 1265/* 1266 * Find a block in the specified cylinder group. 1267 * 1268 * It is a panic if a request is made to find a block if none are 1269 * available. 1270 */ 1271static daddr_t 1272ext2_mapsearch(struct m_ext2fs *fs, char *bbp, daddr_t bpref) 1273{ 1274 char *loc; 1275 int start, len; 1276 1277 /* 1278 * find the fragment by searching through the free block 1279 * map for an appropriate bit pattern 1280 */ 1281 if (bpref) 1282 start = dtogd(fs, bpref) / NBBY; 1283 else 1284 start = 0; 1285 len = howmany(fs->e2fs->e2fs_fpg, NBBY) - start; 1286 loc = memcchr(&bbp[start], 0xff, len); 1287 if (loc == NULL) { 1288 len = start + 1; 1289 start = 0; 1290 loc = memcchr(&bbp[start], 0xff, len); 1291 if (loc == NULL) { 1292 printf("start = %d, len = %d, fs = %s\n", 1293 start, len, fs->e2fs_fsmnt); 1294 panic("ext2_mapsearch: map corrupted"); 1295 /* NOTREACHED */ 1296 } 1297 } 1298 return ((loc - bbp) * NBBY + ffs(~*loc) - 1); 1299} 1300 1301/* 1302 * Fserr prints the name of a filesystem with an error diagnostic. 1303 * 1304 * The form of the error message is: 1305 * fs: error message 1306 */ 1307void 1308ext2_fserr(struct m_ext2fs *fs, uid_t uid, char *cp) 1309{ 1310 1311 log(LOG_ERR, "uid %u on %s: %s\n", uid, fs->e2fs_fsmnt, cp); 1312} 1313 1314int 1315ext2_cg_has_sb(struct m_ext2fs *fs, int cg) 1316{ 1317 int a3, a5, a7; 1318 1319 if (cg == 0) 1320 return (1); 1321 1322 if (EXT2_HAS_COMPAT_FEATURE(fs, EXT2F_COMPAT_SPARSESUPER2)) { 1323 if (cg == fs->e2fs->e4fs_backup_bgs[0] || 1324 cg == fs->e2fs->e4fs_backup_bgs[1]) 1325 return (1); 1326 return (0); 1327 } 1328 1329 if ((cg <= 1) || 1330 !EXT2_HAS_RO_COMPAT_FEATURE(fs, EXT2F_ROCOMPAT_SPARSESUPER)) 1331 return (1); 1332 1333 if (!(cg & 1)) 1334 return (0); 1335 1336 for (a3 = 3, a5 = 5, a7 = 7; 1337 a3 <= cg || a5 <= cg || a7 <= cg; 1338 a3 *= 3, a5 *= 5, a7 *= 7) 1339 if (cg == a3 || cg == a5 || cg == a7) 1340 return (1); 1341 return (0); 1342} 1343