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sys/ufs/ufs/ufs_lookup.c
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1 /*- 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)ufs_lookup.c 8.15 (Berkeley) 6/16/95 35 */ 36 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include "opt_ffs_broken_fixme.h" 41 #include "opt_ufs.h" 42 #include "opt_quota.h" 43 44 #include <sys/param.h> 45 #include <sys/systm.h> 46 #include <sys/kernel.h> 47 #include <sys/namei.h> 48 #include <sys/bio.h> 49 #include <sys/buf.h> 50 #include <sys/proc.h> 51 #include <sys/stat.h> 52 #include <sys/mount.h> 53 #include <sys/vnode.h> 54 #include <sys/sysctl.h> 55 56 #include <vm/vm.h> 57 #include <vm/vm_extern.h> 58 59 #include <ufs/ufs/extattr.h> 60 #include <ufs/ufs/quota.h> 61 #include <ufs/ufs/inode.h> 62 #include <ufs/ufs/dir.h> 63 #ifdef UFS_DIRHASH 64 #include <ufs/ufs/dirhash.h> 65 #endif 66 #include <ufs/ufs/ufsmount.h> 67 #include <ufs/ufs/ufs_extern.h> 68 69 #ifdef DIAGNOSTIC 70 static int dirchk = 1; 71 #else 72 static int dirchk = 0; 73 #endif 74 75 SYSCTL_INT(_debug, OID_AUTO, dircheck, CTLFLAG_RW, &dirchk, 0, ""); 76 77 /* true if old FS format...*/ 78 #define OFSFMT(vp) ((vp)->v_mount->mnt_maxsymlinklen <= 0) 79 80 static int ufs_lookup_(struct vnode *, struct vnode **, struct componentname *, 81 ino_t *); 82 83 /* 84 * Convert a component of a pathname into a pointer to a locked inode. 85 * This is a very central and rather complicated routine. 86 * If the filesystem is not maintained in a strict tree hierarchy, 87 * this can result in a deadlock situation (see comments in code below). 88 * 89 * The cnp->cn_nameiop argument is LOOKUP, CREATE, RENAME, or DELETE depending 90 * on whether the name is to be looked up, created, renamed, or deleted. 91 * When CREATE, RENAME, or DELETE is specified, information usable in 92 * creating, renaming, or deleting a directory entry may be calculated. 93 * If flag has LOCKPARENT or'ed into it and the target of the pathname 94 * exists, lookup returns both the target and its parent directory locked. 95 * When creating or renaming and LOCKPARENT is specified, the target may 96 * not be ".". When deleting and LOCKPARENT is specified, the target may 97 * be "."., but the caller must check to ensure it does an vrele and vput 98 * instead of two vputs. 99 * 100 * This routine is actually used as VOP_CACHEDLOOKUP method, and the 101 * filesystem employs the generic vfs_cache_lookup() as VOP_LOOKUP 102 * method. 103 * 104 * vfs_cache_lookup() performs the following for us: 105 * check that it is a directory 106 * check accessibility of directory 107 * check for modification attempts on read-only mounts 108 * if name found in cache 109 * if at end of path and deleting or creating 110 * drop it 111 * else 112 * return name. 113 * return VOP_CACHEDLOOKUP() 114 * 115 * Overall outline of ufs_lookup: 116 * 117 * search for name in directory, to found or notfound 118 * notfound: 119 * if creating, return locked directory, leaving info on available slots 120 * else return error 121 * found: 122 * if at end of path and deleting, return information to allow delete 123 * if at end of path and rewriting (RENAME and LOCKPARENT), lock target 124 * inode and return info to allow rewrite 125 * if not at end, add name to cache; if at end and neither creating 126 * nor deleting, add name to cache 127 */ 128 int 129 ufs_lookup(ap) 130 struct vop_cachedlookup_args /* { 131 struct vnode *a_dvp; 132 struct vnode **a_vpp; 133 struct componentname *a_cnp; 134 } */ *ap; 135 { 136 137 return (ufs_lookup_(ap->a_dvp, ap->a_vpp, ap->a_cnp, NULL)); 138 } 139 140 static int 141 ufs_lookup_(struct vnode *vdp, struct vnode **vpp, struct componentname *cnp, 142 ino_t *dd_ino) 143 { 144 struct inode *dp; /* inode for directory being searched */ 145 struct buf *bp; /* a buffer of directory entries */ 146 struct direct *ep; /* the current directory entry */ 147 int entryoffsetinblock; /* offset of ep in bp's buffer */ 148 enum {NONE, COMPACT, FOUND} slotstatus; 149 doff_t slotoffset; /* offset of area with free space */ 150 doff_t i_diroff; /* cached i_diroff value. */ 151 doff_t i_offset; /* cached i_offset value. */ 152 int slotsize; /* size of area at slotoffset */ 153 int slotfreespace; /* amount of space free in slot */ 154 int slotneeded; /* size of the entry we're seeking */ 155 int numdirpasses; /* strategy for directory search */ 156 doff_t endsearch; /* offset to end directory search */ 157 doff_t prevoff; /* prev entry dp->i_offset */ 158 struct vnode *pdp; /* saved dp during symlink work */ 159 struct vnode *tdp; /* returned by VFS_VGET */ 160 doff_t enduseful; /* pointer past last used dir slot */ 161 u_long bmask; /* block offset mask */ 162 int namlen, error; 163 struct ucred *cred = cnp->cn_cred; 164 int flags = cnp->cn_flags; 165 int nameiop = cnp->cn_nameiop; 166 struct thread *td = cnp->cn_thread; 167 ino_t ino, ino1; 168 int ltype; 169 170 if (vpp != NULL) 171 *vpp = NULL; 172 173 dp = VTOI(vdp); 174 175 /* 176 * Create a vm object if vmiodirenable is enabled. 177 * Alternatively we could call vnode_create_vobject 178 * in VFS_VGET but we could end up creating objects 179 * that are never used. 180 */ 181 vnode_create_vobject(vdp, DIP(dp, i_size), cnp->cn_thread); 182 183 bmask = VFSTOUFS(vdp->v_mount)->um_mountp->mnt_stat.f_iosize - 1; 184 185 restart: 186 bp = NULL; 187 slotoffset = -1; 188 189 /* 190 * We now have a segment name to search for, and a directory to search. 191 * 192 * Suppress search for slots unless creating 193 * file and at end of pathname, in which case 194 * we watch for a place to put the new file in 195 * case it doesn't already exist. 196 */ 197 ino = 0; 198 i_diroff = dp->i_diroff; 199 slotstatus = FOUND; 200 slotfreespace = slotsize = slotneeded = 0; 201 if ((nameiop == CREATE || nameiop == RENAME) && 202 (flags & ISLASTCN)) { 203 slotstatus = NONE; 204 slotneeded = DIRECTSIZ(cnp->cn_namelen); 205 } 206 207 #ifdef UFS_DIRHASH 208 /* 209 * Use dirhash for fast operations on large directories. The logic 210 * to determine whether to hash the directory is contained within 211 * ufsdirhash_build(); a zero return means that it decided to hash 212 * this directory and it successfully built up the hash table. 213 */ 214 if (ufsdirhash_build(dp) == 0) { 215 /* Look for a free slot if needed. */ 216 enduseful = dp->i_size; 217 if (slotstatus != FOUND) { 218 slotoffset = ufsdirhash_findfree(dp, slotneeded, 219 &slotsize); 220 if (slotoffset >= 0) { 221 slotstatus = COMPACT; 222 enduseful = ufsdirhash_enduseful(dp); 223 if (enduseful < 0) 224 enduseful = dp->i_size; 225 } 226 } 227 /* Look up the component. */ 228 numdirpasses = 1; 229 entryoffsetinblock = 0; /* silence compiler warning */ 230 switch (ufsdirhash_lookup(dp, cnp->cn_nameptr, cnp->cn_namelen, 231 &i_offset, &bp, nameiop == DELETE ? &prevoff : NULL)) { 232 case 0: 233 ep = (struct direct *)((char *)bp->b_data + 234 (i_offset & bmask)); 235 goto foundentry; 236 case ENOENT: 237 i_offset = roundup2(dp->i_size, DIRBLKSIZ); 238 goto notfound; 239 default: 240 /* Something failed; just do a linear search. */ 241 break; 242 } 243 } 244 #endif /* UFS_DIRHASH */ 245 /* 246 * If there is cached information on a previous search of 247 * this directory, pick up where we last left off. 248 * We cache only lookups as these are the most common 249 * and have the greatest payoff. Caching CREATE has little 250 * benefit as it usually must search the entire directory 251 * to determine that the entry does not exist. Caching the 252 * location of the last DELETE or RENAME has not reduced 253 * profiling time and hence has been removed in the interest 254 * of simplicity. 255 */ 256 if (nameiop != LOOKUP || i_diroff == 0 || i_diroff >= dp->i_size) { 257 entryoffsetinblock = 0; 258 i_offset = 0; 259 numdirpasses = 1; 260 } else { 261 i_offset = i_diroff; 262 if ((entryoffsetinblock = i_offset & bmask) && 263 (error = UFS_BLKATOFF(vdp, (off_t)i_offset, NULL, &bp))) 264 return (error); 265 numdirpasses = 2; 266 nchstats.ncs_2passes++; 267 } 268 prevoff = i_offset; 269 endsearch = roundup2(dp->i_size, DIRBLKSIZ); 270 enduseful = 0; 271 272 searchloop: 273 while (i_offset < endsearch) { 274 /* 275 * If necessary, get the next directory block. 276 */ 277 if ((i_offset & bmask) == 0) { 278 if (bp != NULL) 279 brelse(bp); 280 error = 281 UFS_BLKATOFF(vdp, (off_t)i_offset, NULL, &bp); 282 if (error) 283 return (error); 284 entryoffsetinblock = 0; 285 } 286 /* 287 * If still looking for a slot, and at a DIRBLKSIZE 288 * boundary, have to start looking for free space again. 289 */ 290 if (slotstatus == NONE && 291 (entryoffsetinblock & (DIRBLKSIZ - 1)) == 0) { 292 slotoffset = -1; 293 slotfreespace = 0; 294 } 295 /* 296 * Get pointer to next entry. 297 * Full validation checks are slow, so we only check 298 * enough to insure forward progress through the 299 * directory. Complete checks can be run by patching 300 * "dirchk" to be true. 301 */ 302 ep = (struct direct *)((char *)bp->b_data + entryoffsetinblock); 303 if (ep->d_reclen == 0 || ep->d_reclen > 304 DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1)) || 305 (dirchk && ufs_dirbadentry(vdp, ep, entryoffsetinblock))) { 306 int i; 307 308 ufs_dirbad(dp, i_offset, "mangled entry"); 309 i = DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1)); 310 i_offset += i; 311 entryoffsetinblock += i; 312 continue; 313 } 314 315 /* 316 * If an appropriate sized slot has not yet been found, 317 * check to see if one is available. Also accumulate space 318 * in the current block so that we can determine if 319 * compaction is viable. 320 */ 321 if (slotstatus != FOUND) { 322 int size = ep->d_reclen; 323 324 if (ep->d_ino != 0) 325 size -= DIRSIZ(OFSFMT(vdp), ep); 326 if (size > 0) { 327 if (size >= slotneeded) { 328 slotstatus = FOUND; 329 slotoffset = i_offset; 330 slotsize = ep->d_reclen; 331 } else if (slotstatus == NONE) { 332 slotfreespace += size; 333 if (slotoffset == -1) 334 slotoffset = i_offset; 335 if (slotfreespace >= slotneeded) { 336 slotstatus = COMPACT; 337 slotsize = i_offset + 338 ep->d_reclen - slotoffset; 339 } 340 } 341 } 342 } 343 344 /* 345 * Check for a name match. 346 */ 347 if (ep->d_ino) { 348 # if (BYTE_ORDER == LITTLE_ENDIAN) 349 if (OFSFMT(vdp)) 350 namlen = ep->d_type; 351 else 352 namlen = ep->d_namlen; 353 # else 354 namlen = ep->d_namlen; 355 # endif 356 if (namlen == cnp->cn_namelen && 357 (cnp->cn_nameptr[0] == ep->d_name[0]) && 358 !bcmp(cnp->cn_nameptr, ep->d_name, 359 (unsigned)namlen)) { 360 #ifdef UFS_DIRHASH 361 foundentry: 362 #endif 363 /* 364 * Save directory entry's inode number and 365 * reclen in ndp->ni_ufs area, and release 366 * directory buffer. 367 */ 368 if (vdp->v_mount->mnt_maxsymlinklen > 0 && 369 ep->d_type == DT_WHT) { 370 slotstatus = FOUND; 371 slotoffset = i_offset; 372 slotsize = ep->d_reclen; 373 enduseful = dp->i_size; 374 cnp->cn_flags |= ISWHITEOUT; 375 numdirpasses--; 376 goto notfound; 377 } 378 ino = ep->d_ino; 379 goto found; 380 } 381 } 382 prevoff = i_offset; 383 i_offset += ep->d_reclen; 384 entryoffsetinblock += ep->d_reclen; 385 if (ep->d_ino) 386 enduseful = i_offset; 387 } 388 notfound: 389 /* 390 * If we started in the middle of the directory and failed 391 * to find our target, we must check the beginning as well. 392 */ 393 if (numdirpasses == 2) { 394 numdirpasses--; 395 i_offset = 0; 396 endsearch = i_diroff; 397 goto searchloop; 398 } 399 if (bp != NULL) 400 brelse(bp); 401 /* 402 * If creating, and at end of pathname and current 403 * directory has not been removed, then can consider 404 * allowing file to be created. 405 */ 406 if ((nameiop == CREATE || nameiop == RENAME || 407 (nameiop == DELETE && 408 (cnp->cn_flags & DOWHITEOUT) && 409 (cnp->cn_flags & ISWHITEOUT))) && 410 (flags & ISLASTCN) && dp->i_effnlink != 0) { 411 /* 412 * Access for write is interpreted as allowing 413 * creation of files in the directory. 414 */ 415 error = VOP_ACCESS(vdp, VWRITE, cred, cnp->cn_thread); 416 if (error) 417 return (error); 418 /* 419 * Return an indication of where the new directory 420 * entry should be put. If we didn't find a slot, 421 * then set dp->i_count to 0 indicating 422 * that the new slot belongs at the end of the 423 * directory. If we found a slot, then the new entry 424 * can be put in the range from dp->i_offset to 425 * dp->i_offset + dp->i_count. 426 */ 427 if (slotstatus == NONE) { 428 dp->i_offset = roundup2(dp->i_size, DIRBLKSIZ); 429 dp->i_count = 0; 430 enduseful = dp->i_offset; 431 } else if (nameiop == DELETE) { 432 dp->i_offset = slotoffset; 433 if ((dp->i_offset & (DIRBLKSIZ - 1)) == 0) 434 dp->i_count = 0; 435 else 436 dp->i_count = dp->i_offset - prevoff; 437 } else { 438 dp->i_offset = slotoffset; 439 dp->i_count = slotsize; 440 if (enduseful < slotoffset + slotsize) 441 enduseful = slotoffset + slotsize; 442 } 443 dp->i_endoff = roundup2(enduseful, DIRBLKSIZ); 444 /* 445 * We return with the directory locked, so that 446 * the parameters we set up above will still be 447 * valid if we actually decide to do a direnter(). 448 * We return ni_vp == NULL to indicate that the entry 449 * does not currently exist; we leave a pointer to 450 * the (locked) directory inode in ndp->ni_dvp. 451 * The pathname buffer is saved so that the name 452 * can be obtained later. 453 * 454 * NB - if the directory is unlocked, then this 455 * information cannot be used. 456 */ 457 cnp->cn_flags |= SAVENAME; 458 return (EJUSTRETURN); 459 } 460 /* 461 * Insert name into cache (as non-existent) if appropriate. 462 */ 463 if ((cnp->cn_flags & MAKEENTRY) && nameiop != CREATE) 464 cache_enter(vdp, NULL, cnp); 465 return (ENOENT); 466 467 found: 468 if (numdirpasses == 2) 469 nchstats.ncs_pass2++; 470 /* 471 * Check that directory length properly reflects presence 472 * of this entry. 473 */ 474 if (i_offset + DIRSIZ(OFSFMT(vdp), ep) > dp->i_size) { 475 ufs_dirbad(dp, i_offset, "i_size too small"); 476 dp->i_size = i_offset + DIRSIZ(OFSFMT(vdp), ep); 477 DIP_SET(dp, i_size, dp->i_size); 478 dp->i_flag |= IN_CHANGE | IN_UPDATE; 479 } 480 brelse(bp); 481 482 /* 483 * Found component in pathname. 484 * If the final component of path name, save information 485 * in the cache as to where the entry was found. 486 */ 487 if ((flags & ISLASTCN) && nameiop == LOOKUP) 488 dp->i_diroff = i_offset &~ (DIRBLKSIZ - 1); 489 490 if (dd_ino != NULL) { 491 *dd_ino = ino; 492 return (0); 493 } 494 495 /* 496 * If deleting, and at end of pathname, return 497 * parameters which can be used to remove file. 498 */ 499 if (nameiop == DELETE && (flags & ISLASTCN)) { 500 if (flags & LOCKPARENT) 501 ASSERT_VOP_ELOCKED(vdp, __FUNCTION__); 502 /* 503 * Write access to directory required to delete files. 504 */ 505 error = VOP_ACCESS(vdp, VWRITE, cred, cnp->cn_thread); 506 if (error) 507 return (error); 508 /* 509 * Return pointer to current entry in dp->i_offset, 510 * and distance past previous entry (if there 511 * is a previous entry in this block) in dp->i_count. 512 * Save directory inode pointer in ndp->ni_dvp for dirremove(). 513 * 514 * Technically we shouldn't be setting these in the 515 * WANTPARENT case (first lookup in rename()), but any 516 * lookups that will result in directory changes will 517 * overwrite these. 518 */ 519 dp->i_offset = i_offset; 520 if ((dp->i_offset & (DIRBLKSIZ - 1)) == 0) 521 dp->i_count = 0; 522 else 523 dp->i_count = dp->i_offset - prevoff; 524 if (dp->i_number == ino) { 525 VREF(vdp); 526 *vpp = vdp; 527 return (0); 528 } 529 if ((error = VFS_VGET(vdp->v_mount, ino, 530 LK_EXCLUSIVE, &tdp)) != 0) 531 return (error); 532 /* 533 * If directory is "sticky", then user must own 534 * the directory, or the file in it, else she 535 * may not delete it (unless she's root). This 536 * implements append-only directories. 537 */ 538 if ((dp->i_mode & ISVTX) && 539 VOP_ACCESS(vdp, VADMIN, cred, cnp->cn_thread) && 540 VOP_ACCESS(tdp, VADMIN, cred, cnp->cn_thread)) { 541 vput(tdp); 542 return (EPERM); 543 } 544 *vpp = tdp; 545 return (0); 546 } 547 548 /* 549 * If rewriting (RENAME), return the inode and the 550 * information required to rewrite the present directory 551 * Must get inode of directory entry to verify it's a 552 * regular file, or empty directory. 553 */ 554 if (nameiop == RENAME && (flags & ISLASTCN)) { 555 if ((error = VOP_ACCESS(vdp, VWRITE, cred, cnp->cn_thread))) 556 return (error); 557 /* 558 * Careful about locking second inode. 559 * This can only occur if the target is ".". 560 */ 561 dp->i_offset = i_offset; 562 if (dp->i_number == ino) 563 return (EISDIR); 564 if ((error = VFS_VGET(vdp->v_mount, ino, 565 LK_EXCLUSIVE, &tdp)) != 0) 566 return (error); 567 *vpp = tdp; 568 cnp->cn_flags |= SAVENAME; 569 return (0); 570 } 571 572 /* 573 * Step through the translation in the name. We do not `vput' the 574 * directory because we may need it again if a symbolic link 575 * is relative to the current directory. Instead we save it 576 * unlocked as "pdp". We must get the target inode before unlocking 577 * the directory to insure that the inode will not be removed 578 * before we get it. We prevent deadlock by always fetching 579 * inodes from the root, moving down the directory tree. Thus 580 * when following backward pointers ".." we must unlock the 581 * parent directory before getting the requested directory. 582 * There is a potential race condition here if both the current 583 * and parent directories are removed before the VFS_VGET for the 584 * inode associated with ".." returns. We hope that this occurs 585 * infrequently since we cannot avoid this race condition without 586 * implementing a sophisticated deadlock detection algorithm. 587 * Note also that this simple deadlock detection scheme will not 588 * work if the filesystem has any hard links other than ".." 589 * that point backwards in the directory structure. 590 */ 591 pdp = vdp; 592 if (flags & ISDOTDOT) { 593 error = vn_vget_ino(pdp, ino, cnp->cn_lkflags, &tdp); 594 if (error) 595 return (error); 596 597 /* 598 * Recheck that ".." entry in the vdp directory points 599 * to the inode we looked up before vdp lock was 600 * dropped. 601 */ 602 error = ufs_lookup_(pdp, NULL, cnp, &ino1); 603 if (error) { 604 vput(tdp); 605 return (error); 606 } 607 if (ino1 != ino) { 608 vput(tdp); 609 goto restart; 610 } 611 612 *vpp = tdp; 613 } else if (dp->i_number == ino) { 614 VREF(vdp); /* we want ourself, ie "." */ 615 /* 616 * When we lookup "." we still can be asked to lock it 617 * differently. 618 */ 619 ltype = cnp->cn_lkflags & LK_TYPE_MASK; 620 if (ltype != VOP_ISLOCKED(vdp, td)) { 621 if (ltype == LK_EXCLUSIVE) 622 vn_lock(vdp, LK_UPGRADE | LK_RETRY, td); 623 else /* if (ltype == LK_SHARED) */ 624 vn_lock(vdp, LK_DOWNGRADE | LK_RETRY, td); 625 } 626 *vpp = vdp; 627 } else { 628 error = VFS_VGET(pdp->v_mount, ino, cnp->cn_lkflags, &tdp); 629 if (error) 630 return (error); 631 *vpp = tdp; 632 } 633 634 /* 635 * Insert name into cache if appropriate. 636 */ 637 if (cnp->cn_flags & MAKEENTRY) 638 cache_enter(vdp, *vpp, cnp); 639 return (0); 640 } 641 642 void 643 ufs_dirbad(ip, offset, how) 644 struct inode *ip; 645 doff_t offset; 646 char *how; 647 { 648 struct mount *mp; 649 650 mp = ITOV(ip)->v_mount; 651 if ((mp->mnt_flag & MNT_RDONLY) == 0) 652 panic("ufs_dirbad: %s: bad dir ino %lu at offset %ld: %s", 653 mp->mnt_stat.f_mntonname, (u_long)ip->i_number, (long)offset, how); 654 else 655 (void)printf("%s: bad dir ino %lu at offset %ld: %s\n", 656 mp->mnt_stat.f_mntonname, (u_long)ip->i_number, (long)offset, how); 657 } 658 659 /* 660 * Do consistency checking on a directory entry: 661 * record length must be multiple of 4 662 * entry must fit in rest of its DIRBLKSIZ block 663 * record must be large enough to contain entry 664 * name is not longer than MAXNAMLEN 665 * name must be as long as advertised, and null terminated 666 */ 667 int 668 ufs_dirbadentry(dp, ep, entryoffsetinblock) 669 struct vnode *dp; 670 struct direct *ep; 671 int entryoffsetinblock; 672 { 673 int i, namlen; 674 675 # if (BYTE_ORDER == LITTLE_ENDIAN) 676 if (OFSFMT(dp)) 677 namlen = ep->d_type; 678 else 679 namlen = ep->d_namlen; 680 # else 681 namlen = ep->d_namlen; 682 # endif 683 if ((ep->d_reclen & 0x3) != 0 || 684 ep->d_reclen > DIRBLKSIZ - (entryoffsetinblock & (DIRBLKSIZ - 1)) || 685 ep->d_reclen < DIRSIZ(OFSFMT(dp), ep) || namlen > MAXNAMLEN) { 686 /*return (1); */ 687 printf("First bad\n"); 688 goto bad; 689 } 690 if (ep->d_ino == 0) 691 return (0); 692 for (i = 0; i < namlen; i++) 693 if (ep->d_name[i] == '\0') { 694 /*return (1); */ 695 printf("Second bad\n"); 696 goto bad; 697 } 698 if (ep->d_name[i]) 699 goto bad; 700 return (0); 701 bad: 702 return (1); 703 } 704 705 /* 706 * Construct a new directory entry after a call to namei, using the 707 * parameters that it left in the componentname argument cnp. The 708 * argument ip is the inode to which the new directory entry will refer. 709 */ 710 void 711 ufs_makedirentry(ip, cnp, newdirp) 712 struct inode *ip; 713 struct componentname *cnp; 714 struct direct *newdirp; 715 { 716 717 #ifdef INVARIANTS 718 if ((cnp->cn_flags & SAVENAME) == 0) 719 panic("ufs_makedirentry: missing name"); 720 #endif 721 newdirp->d_ino = ip->i_number; 722 newdirp->d_namlen = cnp->cn_namelen; 723 bcopy(cnp->cn_nameptr, newdirp->d_name, (unsigned)cnp->cn_namelen + 1); 724 if (ITOV(ip)->v_mount->mnt_maxsymlinklen > 0) 725 newdirp->d_type = IFTODT(ip->i_mode); 726 else { 727 newdirp->d_type = 0; 728 # if (BYTE_ORDER == LITTLE_ENDIAN) 729 { u_char tmp = newdirp->d_namlen; 730 newdirp->d_namlen = newdirp->d_type; 731 newdirp->d_type = tmp; } 732 # endif 733 } 734 } 735 736 /* 737 * Write a directory entry after a call to namei, using the parameters 738 * that it left in nameidata. The argument dirp is the new directory 739 * entry contents. Dvp is a pointer to the directory to be written, 740 * which was left locked by namei. Remaining parameters (dp->i_offset, 741 * dp->i_count) indicate how the space for the new entry is to be obtained. 742 * Non-null bp indicates that a directory is being created (for the 743 * soft dependency code). 744 */ 745 int 746 ufs_direnter(dvp, tvp, dirp, cnp, newdirbp) 747 struct vnode *dvp; 748 struct vnode *tvp; 749 struct direct *dirp; 750 struct componentname *cnp; 751 struct buf *newdirbp; 752 { 753 struct ucred *cr; 754 struct thread *td; 755 int newentrysize; 756 struct inode *dp; 757 struct buf *bp; 758 u_int dsize; 759 struct direct *ep, *nep; 760 int error, ret, blkoff, loc, spacefree, flags, namlen; 761 char *dirbuf; 762 763 td = curthread; /* XXX */ 764 cr = td->td_ucred; 765 766 dp = VTOI(dvp); 767 newentrysize = DIRSIZ(OFSFMT(dvp), dirp); 768 769 if (dp->i_count == 0) { 770 /* 771 * If dp->i_count is 0, then namei could find no 772 * space in the directory. Here, dp->i_offset will 773 * be on a directory block boundary and we will write the 774 * new entry into a fresh block. 775 */ 776 if (dp->i_offset & (DIRBLKSIZ - 1)) 777 panic("ufs_direnter: newblk"); 778 flags = BA_CLRBUF; 779 if (!DOINGSOFTDEP(dvp) && !DOINGASYNC(dvp)) 780 flags |= IO_SYNC; 781 #ifdef QUOTA 782 if ((error = getinoquota(dp)) != 0) { 783 if (DOINGSOFTDEP(dvp) && newdirbp != NULL) 784 bdwrite(newdirbp); 785 return (error); 786 } 787 #endif 788 if ((error = UFS_BALLOC(dvp, (off_t)dp->i_offset, DIRBLKSIZ, 789 cr, flags, &bp)) != 0) { 790 if (DOINGSOFTDEP(dvp) && newdirbp != NULL) 791 bdwrite(newdirbp); 792 return (error); 793 } 794 dp->i_size = dp->i_offset + DIRBLKSIZ; 795 DIP_SET(dp, i_size, dp->i_size); 796 dp->i_flag |= IN_CHANGE | IN_UPDATE; 797 vnode_pager_setsize(dvp, (u_long)dp->i_size); 798 dirp->d_reclen = DIRBLKSIZ; 799 blkoff = dp->i_offset & 800 (VFSTOUFS(dvp->v_mount)->um_mountp->mnt_stat.f_iosize - 1); 801 bcopy((caddr_t)dirp, (caddr_t)bp->b_data + blkoff,newentrysize); 802 #ifdef UFS_DIRHASH 803 if (dp->i_dirhash != NULL) { 804 ufsdirhash_newblk(dp, dp->i_offset); 805 ufsdirhash_add(dp, dirp, dp->i_offset); 806 ufsdirhash_checkblock(dp, (char *)bp->b_data + blkoff, 807 dp->i_offset); 808 } 809 #endif 810 if (DOINGSOFTDEP(dvp)) { 811 /* 812 * Ensure that the entire newly allocated block is a 813 * valid directory so that future growth within the 814 * block does not have to ensure that the block is 815 * written before the inode. 816 */ 817 blkoff += DIRBLKSIZ; 818 while (blkoff < bp->b_bcount) { 819 ((struct direct *) 820 (bp->b_data + blkoff))->d_reclen = DIRBLKSIZ; 821 blkoff += DIRBLKSIZ; 822 } 823 if (softdep_setup_directory_add(bp, dp, dp->i_offset, 824 dirp->d_ino, newdirbp, 1) == 0) { 825 bdwrite(bp); 826 return (UFS_UPDATE(dvp, 0)); 827 } 828 /* We have just allocated a directory block in an 829 * indirect block. Rather than tracking when it gets 830 * claimed by the inode, we simply do a VOP_FSYNC 831 * now to ensure that it is there (in case the user 832 * does a future fsync). Note that we have to unlock 833 * the inode for the entry that we just entered, as 834 * the VOP_FSYNC may need to lock other inodes which 835 * can lead to deadlock if we also hold a lock on 836 * the newly entered node. 837 */ 838 if ((error = bwrite(bp))) 839 return (error); 840 if (tvp != NULL) 841 VOP_UNLOCK(tvp, 0, td); 842 error = VOP_FSYNC(dvp, MNT_WAIT, td); 843 if (tvp != NULL) 844 vn_lock(tvp, LK_EXCLUSIVE | LK_RETRY, td); 845 return (error); 846 } 847 if (DOINGASYNC(dvp)) { 848 bdwrite(bp); 849 return (UFS_UPDATE(dvp, 0)); 850 } 851 error = bwrite(bp); 852 ret = UFS_UPDATE(dvp, 1); 853 if (error == 0) 854 return (ret); 855 return (error); 856 } 857 858 /* 859 * If dp->i_count is non-zero, then namei found space for the new 860 * entry in the range dp->i_offset to dp->i_offset + dp->i_count 861 * in the directory. To use this space, we may have to compact 862 * the entries located there, by copying them together towards the 863 * beginning of the block, leaving the free space in one usable 864 * chunk at the end. 865 */ 866 867 /* 868 * Increase size of directory if entry eats into new space. 869 * This should never push the size past a new multiple of 870 * DIRBLKSIZE. 871 * 872 * N.B. - THIS IS AN ARTIFACT OF 4.2 AND SHOULD NEVER HAPPEN. 873 */ 874 if (dp->i_offset + dp->i_count > dp->i_size) { 875 dp->i_size = dp->i_offset + dp->i_count; 876 DIP_SET(dp, i_size, dp->i_size); 877 } 878 /* 879 * Get the block containing the space for the new directory entry. 880 */ 881 error = UFS_BLKATOFF(dvp, (off_t)dp->i_offset, &dirbuf, &bp); 882 if (error) { 883 if (DOINGSOFTDEP(dvp) && newdirbp != NULL) 884 bdwrite(newdirbp); 885 return (error); 886 } 887 /* 888 * Find space for the new entry. In the simple case, the entry at 889 * offset base will have the space. If it does not, then namei 890 * arranged that compacting the region dp->i_offset to 891 * dp->i_offset + dp->i_count would yield the space. 892 */ 893 ep = (struct direct *)dirbuf; 894 dsize = ep->d_ino ? DIRSIZ(OFSFMT(dvp), ep) : 0; 895 spacefree = ep->d_reclen - dsize; 896 for (loc = ep->d_reclen; loc < dp->i_count; ) { 897 nep = (struct direct *)(dirbuf + loc); 898 899 /* Trim the existing slot (NB: dsize may be zero). */ 900 ep->d_reclen = dsize; 901 ep = (struct direct *)((char *)ep + dsize); 902 903 /* Read nep->d_reclen now as the bcopy() may clobber it. */ 904 loc += nep->d_reclen; 905 if (nep->d_ino == 0) { 906 /* 907 * A mid-block unused entry. Such entries are 908 * never created by the kernel, but fsck_ffs 909 * can create them (and it doesn't fix them). 910 * 911 * Add up the free space, and initialise the 912 * relocated entry since we don't bcopy it. 913 */ 914 spacefree += nep->d_reclen; 915 ep->d_ino = 0; 916 dsize = 0; 917 continue; 918 } 919 dsize = DIRSIZ(OFSFMT(dvp), nep); 920 spacefree += nep->d_reclen - dsize; 921 #ifdef UFS_DIRHASH 922 if (dp->i_dirhash != NULL) 923 ufsdirhash_move(dp, nep, 924 dp->i_offset + ((char *)nep - dirbuf), 925 dp->i_offset + ((char *)ep - dirbuf)); 926 #endif 927 if (DOINGSOFTDEP(dvp)) 928 softdep_change_directoryentry_offset(dp, dirbuf, 929 (caddr_t)nep, (caddr_t)ep, dsize); 930 else 931 bcopy((caddr_t)nep, (caddr_t)ep, dsize); 932 } 933 /* 934 * Here, `ep' points to a directory entry containing `dsize' in-use 935 * bytes followed by `spacefree' unused bytes. If ep->d_ino == 0, 936 * then the entry is completely unused (dsize == 0). The value 937 * of ep->d_reclen is always indeterminate. 938 * 939 * Update the pointer fields in the previous entry (if any), 940 * copy in the new entry, and write out the block. 941 */ 942 # if (BYTE_ORDER == LITTLE_ENDIAN) 943 if (OFSFMT(dvp)) 944 namlen = ep->d_type; 945 else 946 namlen = ep->d_namlen; 947 # else 948 namlen = ep->d_namlen; 949 # endif 950 if (ep->d_ino == 0 || 951 (ep->d_ino == WINO && namlen == dirp->d_namlen && 952 bcmp(ep->d_name, dirp->d_name, dirp->d_namlen) == 0)) { 953 if (spacefree + dsize < newentrysize) 954 panic("ufs_direnter: compact1"); 955 dirp->d_reclen = spacefree + dsize; 956 } else { 957 if (spacefree < newentrysize) 958 panic("ufs_direnter: compact2"); 959 dirp->d_reclen = spacefree; 960 ep->d_reclen = dsize; 961 ep = (struct direct *)((char *)ep + dsize); 962 } 963 #ifdef UFS_DIRHASH 964 if (dp->i_dirhash != NULL && (ep->d_ino == 0 || 965 dirp->d_reclen == spacefree)) 966 ufsdirhash_add(dp, dirp, dp->i_offset + ((char *)ep - dirbuf)); 967 #endif 968 bcopy((caddr_t)dirp, (caddr_t)ep, (u_int)newentrysize); 969 #ifdef UFS_DIRHASH 970 if (dp->i_dirhash != NULL) 971 ufsdirhash_checkblock(dp, dirbuf - 972 (dp->i_offset & (DIRBLKSIZ - 1)), 973 dp->i_offset & ~(DIRBLKSIZ - 1)); 974 #endif 975 976 if (DOINGSOFTDEP(dvp)) { 977 (void) softdep_setup_directory_add(bp, dp, 978 dp->i_offset + (caddr_t)ep - dirbuf, 979 dirp->d_ino, newdirbp, 0); 980 bdwrite(bp); 981 } else { 982 if (DOINGASYNC(dvp)) { 983 bdwrite(bp); 984 error = 0; 985 } else { 986 error = bwrite(bp); 987 } 988 } 989 dp->i_flag |= IN_CHANGE | IN_UPDATE; 990 /* 991 * If all went well, and the directory can be shortened, proceed 992 * with the truncation. Note that we have to unlock the inode for 993 * the entry that we just entered, as the truncation may need to 994 * lock other inodes which can lead to deadlock if we also hold a 995 * lock on the newly entered node. 996 */ 997 if (error == 0 && dp->i_endoff && dp->i_endoff < dp->i_size) { 998 if (tvp != NULL) 999 VOP_UNLOCK(tvp, 0, td); 1000 #ifdef UFS_DIRHASH 1001 if (dp->i_dirhash != NULL) 1002 ufsdirhash_dirtrunc(dp, dp->i_endoff); 1003 #endif 1004 (void) UFS_TRUNCATE(dvp, (off_t)dp->i_endoff, 1005 IO_NORMAL | IO_SYNC, cr, td); 1006 if (tvp != NULL) 1007 vn_lock(tvp, LK_EXCLUSIVE | LK_RETRY, td); 1008 } 1009 return (error); 1010 } 1011 1012 /* 1013 * Remove a directory entry after a call to namei, using 1014 * the parameters which it left in nameidata. The entry 1015 * dp->i_offset contains the offset into the directory of the 1016 * entry to be eliminated. The dp->i_count field contains the 1017 * size of the previous record in the directory. If this 1018 * is 0, the first entry is being deleted, so we need only 1019 * zero the inode number to mark the entry as free. If the 1020 * entry is not the first in the directory, we must reclaim 1021 * the space of the now empty record by adding the record size 1022 * to the size of the previous entry. 1023 */ 1024 int 1025 ufs_dirremove(dvp, ip, flags, isrmdir) 1026 struct vnode *dvp; 1027 struct inode *ip; 1028 int flags; 1029 int isrmdir; 1030 { 1031 struct inode *dp; 1032 struct direct *ep, *rep; 1033 struct buf *bp; 1034 int error; 1035 1036 dp = VTOI(dvp); 1037 1038 if (flags & DOWHITEOUT) { 1039 /* 1040 * Whiteout entry: set d_ino to WINO. 1041 */ 1042 if ((error = 1043 UFS_BLKATOFF(dvp, (off_t)dp->i_offset, (char **)&ep, &bp)) != 0) 1044 return (error); 1045 ep->d_ino = WINO; 1046 ep->d_type = DT_WHT; 1047 goto out; 1048 } 1049 1050 if ((error = UFS_BLKATOFF(dvp, 1051 (off_t)(dp->i_offset - dp->i_count), (char **)&ep, &bp)) != 0) 1052 return (error); 1053 1054 /* Set 'rep' to the entry being removed. */ 1055 if (dp->i_count == 0) 1056 rep = ep; 1057 else 1058 rep = (struct direct *)((char *)ep + ep->d_reclen); 1059 #ifdef UFS_DIRHASH 1060 /* 1061 * Remove the dirhash entry. This is complicated by the fact 1062 * that `ep' is the previous entry when dp->i_count != 0. 1063 */ 1064 if (dp->i_dirhash != NULL) 1065 ufsdirhash_remove(dp, rep, dp->i_offset); 1066 #endif 1067 if (dp->i_count == 0) { 1068 /* 1069 * First entry in block: set d_ino to zero. 1070 */ 1071 ep->d_ino = 0; 1072 } else { 1073 /* 1074 * Collapse new free space into previous entry. 1075 */ 1076 ep->d_reclen += rep->d_reclen; 1077 } 1078 #ifdef UFS_DIRHASH 1079 if (dp->i_dirhash != NULL) 1080 ufsdirhash_checkblock(dp, (char *)ep - 1081 ((dp->i_offset - dp->i_count) & (DIRBLKSIZ - 1)), 1082 dp->i_offset & ~(DIRBLKSIZ - 1)); 1083 #endif 1084 out: 1085 if (DOINGSOFTDEP(dvp)) { 1086 if (ip) { 1087 ip->i_effnlink--; 1088 softdep_change_linkcnt(ip); 1089 softdep_setup_remove(bp, dp, ip, isrmdir); 1090 } 1091 if (softdep_slowdown(dvp)) { 1092 error = bwrite(bp); 1093 } else { 1094 bdwrite(bp); 1095 error = 0; 1096 } 1097 } else { 1098 if (ip) { 1099 ip->i_effnlink--; 1100 ip->i_nlink--; 1101 DIP_SET(ip, i_nlink, ip->i_nlink); 1102 ip->i_flag |= IN_CHANGE; 1103 } 1104 if (flags & DOWHITEOUT) 1105 error = bwrite(bp); 1106 else if (DOINGASYNC(dvp) && dp->i_count != 0) { 1107 bdwrite(bp); 1108 error = 0; 1109 } else 1110 error = bwrite(bp); 1111 } 1112 dp->i_flag |= IN_CHANGE | IN_UPDATE; 1113 /* 1114 * If the last named reference to a snapshot goes away, 1115 * drop its snapshot reference so that it will be reclaimed 1116 * when last open reference goes away. 1117 */ 1118 #if defined(FFS) || defined(IFS) 1119 if (ip != 0 && (ip->i_flags & SF_SNAPSHOT) != 0 && ip->i_effnlink == 0) 1120 ffs_snapgone(ip); 1121 #endif 1122 return (error); 1123 } 1124 1125 /* 1126 * Rewrite an existing directory entry to point at the inode 1127 * supplied. The parameters describing the directory entry are 1128 * set up by a call to namei. 1129 */ 1130 int 1131 ufs_dirrewrite(dp, oip, newinum, newtype, isrmdir) 1132 struct inode *dp, *oip; 1133 ino_t newinum; 1134 int newtype; 1135 int isrmdir; 1136 { 1137 struct buf *bp; 1138 struct direct *ep; 1139 struct vnode *vdp = ITOV(dp); 1140 int error; 1141 1142 error = UFS_BLKATOFF(vdp, (off_t)dp->i_offset, (char **)&ep, &bp); 1143 if (error) 1144 return (error); 1145 ep->d_ino = newinum; 1146 if (!OFSFMT(vdp)) 1147 ep->d_type = newtype; 1148 oip->i_effnlink--; 1149 if (DOINGSOFTDEP(vdp)) { 1150 softdep_change_linkcnt(oip); 1151 softdep_setup_directory_change(bp, dp, oip, newinum, isrmdir); 1152 bdwrite(bp); 1153 } else { 1154 oip->i_nlink--; 1155 DIP_SET(oip, i_nlink, oip->i_nlink); 1156 oip->i_flag |= IN_CHANGE; 1157 if (DOINGASYNC(vdp)) { 1158 bdwrite(bp); 1159 error = 0; 1160 } else { 1161 error = bwrite(bp); 1162 } 1163 } 1164 dp->i_flag |= IN_CHANGE | IN_UPDATE; 1165 /* 1166 * If the last named reference to a snapshot goes away, 1167 * drop its snapshot reference so that it will be reclaimed 1168 * when last open reference goes away. 1169 */ 1170 #if defined(FFS) || defined(IFS) 1171 if ((oip->i_flags & SF_SNAPSHOT) != 0 && oip->i_effnlink == 0) 1172 ffs_snapgone(oip); 1173 #endif 1174 return (error); 1175 } 1176 1177 /* 1178 * Check if a directory is empty or not. 1179 * Inode supplied must be locked. 1180 * 1181 * Using a struct dirtemplate here is not precisely 1182 * what we want, but better than using a struct direct. 1183 * 1184 * NB: does not handle corrupted directories. 1185 */ 1186 int 1187 ufs_dirempty(ip, parentino, cred) 1188 struct inode *ip; 1189 ino_t parentino; 1190 struct ucred *cred; 1191 { 1192 doff_t off; 1193 struct dirtemplate dbuf; 1194 struct direct *dp = (struct direct *)&dbuf; 1195 int error, count, namlen; 1196 #define MINDIRSIZ (sizeof (struct dirtemplate) / 2) 1197 1198 for (off = 0; off < ip->i_size; off += dp->d_reclen) { 1199 error = vn_rdwr(UIO_READ, ITOV(ip), (caddr_t)dp, MINDIRSIZ, 1200 off, UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK, cred, 1201 NOCRED, &count, (struct thread *)0); 1202 /* 1203 * Since we read MINDIRSIZ, residual must 1204 * be 0 unless we're at end of file. 1205 */ 1206 if (error || count != 0) 1207 return (0); 1208 /* avoid infinite loops */ 1209 if (dp->d_reclen == 0) 1210 return (0); 1211 /* skip empty entries */ 1212 if (dp->d_ino == 0 || dp->d_ino == WINO) 1213 continue; 1214 /* accept only "." and ".." */ 1215 # if (BYTE_ORDER == LITTLE_ENDIAN) 1216 if (OFSFMT(ITOV(ip))) 1217 namlen = dp->d_type; 1218 else 1219 namlen = dp->d_namlen; 1220 # else 1221 namlen = dp->d_namlen; 1222 # endif 1223 if (namlen > 2) 1224 return (0); 1225 if (dp->d_name[0] != '.') 1226 return (0); 1227 /* 1228 * At this point namlen must be 1 or 2. 1229 * 1 implies ".", 2 implies ".." if second 1230 * char is also "." 1231 */ 1232 if (namlen == 1 && dp->d_ino == ip->i_number) 1233 continue; 1234 if (dp->d_name[1] == '.' && dp->d_ino == parentino) 1235 continue; 1236 return (0); 1237 } 1238 return (1); 1239 } 1240 1241 static int 1242 ufs_dir_dd_ino(struct vnode *vp, struct ucred *cred, ino_t *dd_ino) 1243 { 1244 struct dirtemplate dirbuf; 1245 int error, namlen; 1246 1247 if (vp->v_type != VDIR) 1248 return (ENOTDIR); 1249 error = vn_rdwr(UIO_READ, vp, (caddr_t)&dirbuf, 1250 sizeof (struct dirtemplate), (off_t)0, UIO_SYSSPACE, 1251 IO_NODELOCKED | IO_NOMACCHECK, cred, NOCRED, NULL, NULL); 1252 if (error != 0) 1253 return (error); 1254 #if (BYTE_ORDER == LITTLE_ENDIAN) 1255 if (OFSFMT(vp)) 1256 namlen = dirbuf.dotdot_type; 1257 else 1258 namlen = dirbuf.dotdot_namlen; 1259 #else 1260 namlen = dirbuf.dotdot_namlen; 1261 #endif 1262 if (namlen != 2 || dirbuf.dotdot_name[0] != '.' || 1263 dirbuf.dotdot_name[1] != '.') 1264 return (ENOTDIR); 1265 *dd_ino = dirbuf.dotdot_ino; 1266 return (0); 1267 } 1268 1269 /* 1270 * Check if source directory is in the path of the target directory. 1271 * Target is supplied locked, source is unlocked. 1272 * The target is always vput before returning. 1273 */ 1274 int 1275 ufs_checkpath(ino_t source_ino, struct inode *target, struct ucred *cred) 1276 { 1277 struct vnode *vp, *vp1; 1278 int error; 1279 ino_t dd_ino; 1280 1281 vp = ITOV(target); 1282 if (target->i_number == source_ino) { 1283 error = EEXIST; 1284 goto out; 1285 } 1286 error = 0; 1287 if (target->i_number == ROOTINO) 1288 goto out; 1289 1290 for (;;) { 1291 error = ufs_dir_dd_ino(vp, cred, &dd_ino); 1292 if (error != 0) 1293 break; 1294 if (dd_ino == source_ino) { 1295 error = EINVAL; 1296 break; 1297 } 1298 if (dd_ino == ROOTINO) 1299 break; 1300 error = vn_vget_ino(vp, dd_ino, LK_EXCLUSIVE, &vp1); 1301 if (error != 0) 1302 break; 1303 /* Recheck that ".." still points to vp1 after relock of vp */ 1304 error = ufs_dir_dd_ino(vp, cred, &dd_ino); 1305 if (error != 0) { 1306 vput(vp1); 1307 break; 1308 } 1309 /* Redo the check of ".." if directory was reparented */ 1310 if (dd_ino != VTOI(vp1)->i_number) { 1311 vput(vp1); 1312 continue; 1313 } 1314 vput(vp); 1315 vp = vp1; 1316 } 1317 1318 out: 1319 if (error == ENOTDIR) 1320 printf("checkpath: .. not a directory\n"); 1321 if (vp != NULL) 1322 vput(vp); 1323 return (error); 1324 }
Cache object: 12048b68a421e0e9a287785112074c8b
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