1 /* $FreeBSD$ */ 2 /* $NetBSD: msdosfs_denode.c,v 1.28 1998/02/10 14:10:00 mrg Exp $ */ 3 4 /*- 5 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. 6 * Copyright (C) 1994, 1995, 1997 TooLs GmbH. 7 * All rights reserved. 8 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). 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 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by TooLs GmbH. 21 * 4. The name of TooLs GmbH may not be used to endorse or promote products 22 * derived from this software without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 27 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 29 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 30 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 32 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 33 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 /*- 36 * Written by Paul Popelka (paulp@uts.amdahl.com) 37 * 38 * You can do anything you want with this software, just don't say you wrote 39 * it, and don't remove this notice. 40 * 41 * This software is provided "as is". 42 * 43 * The author supplies this software to be publicly redistributed on the 44 * understanding that the author is not responsible for the correct 45 * functioning of this software in any circumstances and is not liable for 46 * any damages caused by this software. 47 * 48 * October 1992 49 */ 50 51 #include <sys/param.h> 52 #include <sys/systm.h> 53 #include <sys/kernel.h> 54 #include <sys/mount.h> 55 #include <sys/malloc.h> 56 #include <sys/bio.h> 57 #include <sys/buf.h> 58 #include <sys/vnode.h> 59 #include <sys/mutex.h> 60 61 #include <vm/vm.h> 62 #include <vm/vm_extern.h> 63 64 #include <fs/msdosfs/bpb.h> 65 #include <fs/msdosfs/msdosfsmount.h> 66 #include <fs/msdosfs/direntry.h> 67 #include <fs/msdosfs/denode.h> 68 #include <fs/msdosfs/fat.h> 69 70 static MALLOC_DEFINE(M_MSDOSFSNODE, "MSDOSFS node", "MSDOSFS vnode private part"); 71 72 static struct denode **dehashtbl; 73 static u_long dehash; /* size of hash table - 1 */ 74 #define DEHASH(dev, dcl, doff) (dehashtbl[(minor(dev) + (dcl) + (doff) / \ 75 sizeof(struct direntry)) & dehash]) 76 static struct mtx dehash_mtx; 77 static int dehash_init; 78 79 static struct denode * 80 msdosfs_hashget(struct cdev *dev, u_long dirclust, u_long diroff); 81 static void msdosfs_hashins(struct denode *dep); 82 static void msdosfs_hashrem(struct denode *dep); 83 84 /*ARGSUSED*/ 85 int 86 msdosfs_init(vfsp) 87 struct vfsconf *vfsp; 88 { 89 /* 90 * The following lines prevent us from initializing the mutex 91 * init multiple times. I'm not sure why we get called multiple 92 * times, but the following prevents the panic when we initalize 93 * the mutext the second time. XXX BAD XXX 94 */ 95 if (dehash_init) { 96 printf("Warning: msdosfs_init called more than once!\n"); 97 return (0); 98 } 99 dehash_init++; 100 dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash); 101 mtx_init(&dehash_mtx, "msdosfs dehash", NULL, MTX_DEF); 102 return (0); 103 } 104 105 int 106 msdosfs_uninit(vfsp) 107 struct vfsconf *vfsp; 108 { 109 110 if (dehashtbl) 111 free(dehashtbl, M_MSDOSFSMNT); 112 mtx_destroy(&dehash_mtx); 113 dehash_init--; 114 return (0); 115 } 116 117 static struct denode * 118 msdosfs_hashget(dev, dirclust, diroff) 119 struct cdev *dev; 120 u_long dirclust; 121 u_long diroff; 122 { 123 struct thread *td = curthread; /* XXX */ 124 struct denode *dep; 125 struct vnode *vp; 126 127 loop: 128 mtx_lock(&dehash_mtx); 129 for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) { 130 if (dirclust == dep->de_dirclust 131 && diroff == dep->de_diroffset 132 && dev == dep->de_dev 133 && dep->de_refcnt != 0) { 134 vp = DETOV(dep); 135 mtx_lock(&vp->v_interlock); 136 mtx_unlock(&dehash_mtx); 137 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td)) 138 goto loop; 139 return (dep); 140 } 141 } 142 mtx_unlock(&dehash_mtx); 143 return (NULL); 144 } 145 146 static void 147 msdosfs_hashins(dep) 148 struct denode *dep; 149 { 150 struct denode **depp, *deq; 151 152 mtx_lock(&dehash_mtx); 153 depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset); 154 deq = *depp; 155 if (deq) 156 deq->de_prev = &dep->de_next; 157 dep->de_next = deq; 158 dep->de_prev = depp; 159 *depp = dep; 160 mtx_unlock(&dehash_mtx); 161 } 162 163 static void 164 msdosfs_hashrem(dep) 165 struct denode *dep; 166 { 167 struct denode *deq; 168 169 mtx_lock(&dehash_mtx); 170 deq = dep->de_next; 171 if (deq) 172 deq->de_prev = dep->de_prev; 173 *dep->de_prev = deq; 174 #ifdef DIAGNOSTIC 175 dep->de_next = NULL; 176 dep->de_prev = NULL; 177 #endif 178 mtx_unlock(&dehash_mtx); 179 } 180 181 /* 182 * If deget() succeeds it returns with the gotten denode locked(). 183 * 184 * pmp - address of msdosfsmount structure of the filesystem containing 185 * the denode of interest. The pm_dev field and the address of 186 * the msdosfsmount structure are used. 187 * dirclust - which cluster bp contains, if dirclust is 0 (root directory) 188 * diroffset is relative to the beginning of the root directory, 189 * otherwise it is cluster relative. 190 * diroffset - offset past begin of cluster of denode we want 191 * depp - returns the address of the gotten denode. 192 */ 193 int 194 deget(pmp, dirclust, diroffset, depp) 195 struct msdosfsmount *pmp; /* so we know the maj/min number */ 196 u_long dirclust; /* cluster this dir entry came from */ 197 u_long diroffset; /* index of entry within the cluster */ 198 struct denode **depp; /* returns the addr of the gotten denode */ 199 { 200 int error; 201 struct cdev *dev = pmp->pm_dev; 202 struct mount *mntp = pmp->pm_mountp; 203 struct direntry *direntptr; 204 struct denode *ldep; 205 struct vnode *nvp; 206 struct buf *bp; 207 struct thread *td = curthread; /* XXX */ 208 209 #ifdef MSDOSFS_DEBUG 210 printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n", 211 pmp, dirclust, diroffset, depp); 212 #endif 213 214 /* 215 * On FAT32 filesystems, root is a (more or less) normal 216 * directory 217 */ 218 if (FAT32(pmp) && dirclust == MSDOSFSROOT) 219 dirclust = pmp->pm_rootdirblk; 220 221 /* 222 * See if the denode is in the denode cache. Use the location of 223 * the directory entry to compute the hash value. For subdir use 224 * address of "." entry. For root dir (if not FAT32) use cluster 225 * MSDOSFSROOT, offset MSDOSFSROOT_OFS 226 * 227 * NOTE: The check for de_refcnt > 0 below insures the denode being 228 * examined does not represent an unlinked but still open file. 229 * These files are not to be accessible even when the directory 230 * entry that represented the file happens to be reused while the 231 * deleted file is still open. 232 */ 233 ldep = msdosfs_hashget(dev, dirclust, diroffset); 234 if (ldep) { 235 *depp = ldep; 236 return (0); 237 } 238 239 /* 240 * Do the MALLOC before the getnewvnode since doing so afterward 241 * might cause a bogus v_data pointer to get dereferenced 242 * elsewhere if MALLOC should block. 243 */ 244 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK); 245 246 /* 247 * Directory entry was not in cache, have to create a vnode and 248 * copy it from the passed disk buffer. 249 */ 250 /* getnewvnode() does a VREF() on the vnode */ 251 error = getnewvnode("msdosfs", mntp, &msdosfs_vnodeops, &nvp); 252 if (error) { 253 *depp = NULL; 254 FREE(ldep, M_MSDOSFSNODE); 255 return error; 256 } 257 bzero((caddr_t)ldep, sizeof *ldep); 258 nvp->v_data = ldep; 259 ldep->de_vnode = nvp; 260 ldep->de_flag = 0; 261 ldep->de_dev = dev; 262 ldep->de_dirclust = dirclust; 263 ldep->de_diroffset = diroffset; 264 fc_purge(ldep, 0); /* init the fat cache for this denode */ 265 266 /* 267 * Lock the denode so that it can't be accessed until we've read 268 * it in and have done what we need to it. Do this here instead 269 * of at the start of msdosfs_hashins() so that reinsert() can 270 * call msdosfs_hashins() with a locked denode. 271 */ 272 if (VOP_LOCK(nvp, LK_EXCLUSIVE, td) != 0) 273 panic("deget: unexpected lock failure"); 274 275 /* 276 * Insert the denode into the hash queue. 277 */ 278 msdosfs_hashins(ldep); 279 280 ldep->de_pmp = pmp; 281 ldep->de_refcnt = 1; 282 /* 283 * Copy the directory entry into the denode area of the vnode. 284 */ 285 if ((dirclust == MSDOSFSROOT 286 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk)) 287 && diroffset == MSDOSFSROOT_OFS) { 288 /* 289 * Directory entry for the root directory. There isn't one, 290 * so we manufacture one. We should probably rummage 291 * through the root directory and find a label entry (if it 292 * exists), and then use the time and date from that entry 293 * as the time and date for the root denode. 294 */ 295 nvp->v_vflag |= VV_ROOT; /* should be further down XXX */ 296 297 ldep->de_Attributes = ATTR_DIRECTORY; 298 ldep->de_LowerCase = 0; 299 if (FAT32(pmp)) 300 ldep->de_StartCluster = pmp->pm_rootdirblk; 301 /* de_FileSize will be filled in further down */ 302 else { 303 ldep->de_StartCluster = MSDOSFSROOT; 304 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE; 305 } 306 /* 307 * fill in time and date so that dos2unixtime() doesn't 308 * spit up when called from msdosfs_getattr() with root 309 * denode 310 */ 311 ldep->de_CHun = 0; 312 ldep->de_CTime = 0x0000; /* 00:00:00 */ 313 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT) 314 | (1 << DD_DAY_SHIFT); 315 /* Jan 1, 1980 */ 316 ldep->de_ADate = ldep->de_CDate; 317 ldep->de_MTime = ldep->de_CTime; 318 ldep->de_MDate = ldep->de_CDate; 319 /* leave the other fields as garbage */ 320 } else { 321 error = readep(pmp, dirclust, diroffset, &bp, &direntptr); 322 if (error) { 323 /* 324 * The denode does not contain anything useful, so 325 * it would be wrong to leave it on its hash chain. 326 * Arrange for vput() to just forget about it. 327 */ 328 ldep->de_Name[0] = SLOT_DELETED; 329 330 vput(nvp); 331 *depp = NULL; 332 return (error); 333 } 334 DE_INTERNALIZE(ldep, direntptr); 335 brelse(bp); 336 } 337 338 /* 339 * Fill in a few fields of the vnode and finish filling in the 340 * denode. Then return the address of the found denode. 341 */ 342 if (ldep->de_Attributes & ATTR_DIRECTORY) { 343 /* 344 * Since DOS directory entries that describe directories 345 * have 0 in the filesize field, we take this opportunity 346 * to find out the length of the directory and plug it into 347 * the denode structure. 348 */ 349 u_long size; 350 351 /* 352 * XXX Sometimes, these arrives that . entry have cluster 353 * number 0, when it shouldn't. Use real cluster number 354 * instead of what is written in directory entry. 355 */ 356 if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) { 357 printf("deget(): . entry at clust %ld != %ld\n", 358 dirclust, ldep->de_StartCluster); 359 ldep->de_StartCluster = dirclust; 360 } 361 362 nvp->v_type = VDIR; 363 if (ldep->de_StartCluster != MSDOSFSROOT) { 364 error = pcbmap(ldep, 0xffff, 0, &size, 0); 365 if (error == E2BIG) { 366 ldep->de_FileSize = de_cn2off(pmp, size); 367 error = 0; 368 } else 369 printf("deget(): pcbmap returned %d\n", error); 370 } 371 } else 372 nvp->v_type = VREG; 373 ldep->de_modrev = init_va_filerev(); 374 *depp = ldep; 375 return (0); 376 } 377 378 int 379 deupdat(dep, waitfor) 380 struct denode *dep; 381 int waitfor; 382 { 383 int error; 384 struct buf *bp; 385 struct direntry *dirp; 386 struct timespec ts; 387 388 if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY) 389 return (0); 390 getnanotime(&ts); 391 DETIMES(dep, &ts, &ts, &ts); 392 if ((dep->de_flag & DE_MODIFIED) == 0) 393 return (0); 394 dep->de_flag &= ~DE_MODIFIED; 395 if (dep->de_Attributes & ATTR_DIRECTORY) 396 return (0); 397 if (dep->de_refcnt <= 0) 398 return (0); 399 error = readde(dep, &bp, &dirp); 400 if (error) 401 return (error); 402 DE_EXTERNALIZE(dirp, dep); 403 if (waitfor) 404 return (bwrite(bp)); 405 else { 406 bdwrite(bp); 407 return (0); 408 } 409 } 410 411 /* 412 * Truncate the file described by dep to the length specified by length. 413 */ 414 int 415 detrunc(dep, length, flags, cred, td) 416 struct denode *dep; 417 u_long length; 418 int flags; 419 struct ucred *cred; 420 struct thread *td; 421 { 422 int error; 423 int allerror; 424 u_long eofentry; 425 u_long chaintofree; 426 daddr_t bn; 427 int boff; 428 int isadir = dep->de_Attributes & ATTR_DIRECTORY; 429 struct buf *bp; 430 struct msdosfsmount *pmp = dep->de_pmp; 431 432 #ifdef MSDOSFS_DEBUG 433 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags); 434 #endif 435 436 /* 437 * Disallow attempts to truncate the root directory since it is of 438 * fixed size. That's just the way dos filesystems are. We use 439 * the VROOT bit in the vnode because checking for the directory 440 * bit and a startcluster of 0 in the denode is not adequate to 441 * recognize the root directory at this point in a file or 442 * directory's life. 443 */ 444 if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) { 445 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n", 446 dep->de_dirclust, dep->de_diroffset); 447 return (EINVAL); 448 } 449 450 451 if (dep->de_FileSize < length) { 452 vnode_pager_setsize(DETOV(dep), length); 453 return deextend(dep, length, cred); 454 } 455 456 /* 457 * If the desired length is 0 then remember the starting cluster of 458 * the file and set the StartCluster field in the directory entry 459 * to 0. If the desired length is not zero, then get the number of 460 * the last cluster in the shortened file. Then get the number of 461 * the first cluster in the part of the file that is to be freed. 462 * Then set the next cluster pointer in the last cluster of the 463 * file to CLUST_EOFE. 464 */ 465 if (length == 0) { 466 chaintofree = dep->de_StartCluster; 467 dep->de_StartCluster = 0; 468 eofentry = ~0; 469 } else { 470 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0, 471 &eofentry, 0); 472 if (error) { 473 #ifdef MSDOSFS_DEBUG 474 printf("detrunc(): pcbmap fails %d\n", error); 475 #endif 476 return (error); 477 } 478 } 479 480 fc_purge(dep, de_clcount(pmp, length)); 481 482 /* 483 * If the new length is not a multiple of the cluster size then we 484 * must zero the tail end of the new last cluster in case it 485 * becomes part of the file again because of a seek. 486 */ 487 if ((boff = length & pmp->pm_crbomask) != 0) { 488 if (isadir) { 489 bn = cntobn(pmp, eofentry); 490 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, 491 NOCRED, &bp); 492 if (error) { 493 brelse(bp); 494 #ifdef MSDOSFS_DEBUG 495 printf("detrunc(): bread fails %d\n", error); 496 #endif 497 return (error); 498 } 499 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff); 500 if (flags & IO_SYNC) 501 bwrite(bp); 502 else 503 bdwrite(bp); 504 } 505 } 506 507 /* 508 * Write out the updated directory entry. Even if the update fails 509 * we free the trailing clusters. 510 */ 511 dep->de_FileSize = length; 512 if (!isadir) 513 dep->de_flag |= DE_UPDATE|DE_MODIFIED; 514 allerror = vtruncbuf(DETOV(dep), cred, td, length, pmp->pm_bpcluster); 515 #ifdef MSDOSFS_DEBUG 516 if (allerror) 517 printf("detrunc(): vtruncbuf error %d\n", allerror); 518 #endif 519 error = deupdat(dep, 1); 520 if (error && (allerror == 0)) 521 allerror = error; 522 #ifdef MSDOSFS_DEBUG 523 printf("detrunc(): allerror %d, eofentry %lu\n", 524 allerror, eofentry); 525 #endif 526 527 /* 528 * If we need to break the cluster chain for the file then do it 529 * now. 530 */ 531 if (eofentry != ~0) { 532 error = fatentry(FAT_GET_AND_SET, pmp, eofentry, 533 &chaintofree, CLUST_EOFE); 534 if (error) { 535 #ifdef MSDOSFS_DEBUG 536 printf("detrunc(): fatentry errors %d\n", error); 537 #endif 538 return (error); 539 } 540 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1), 541 eofentry); 542 } 543 544 /* 545 * Now free the clusters removed from the file because of the 546 * truncation. 547 */ 548 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree)) 549 freeclusterchain(pmp, chaintofree); 550 551 return (allerror); 552 } 553 554 /* 555 * Extend the file described by dep to length specified by length. 556 */ 557 int 558 deextend(dep, length, cred) 559 struct denode *dep; 560 u_long length; 561 struct ucred *cred; 562 { 563 struct msdosfsmount *pmp = dep->de_pmp; 564 u_long count; 565 int error; 566 567 /* 568 * The root of a DOS filesystem cannot be extended. 569 */ 570 if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) 571 return (EINVAL); 572 573 /* 574 * Directories cannot be extended. 575 */ 576 if (dep->de_Attributes & ATTR_DIRECTORY) 577 return (EISDIR); 578 579 if (length <= dep->de_FileSize) 580 panic("deextend: file too large"); 581 582 /* 583 * Compute the number of clusters to allocate. 584 */ 585 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize); 586 if (count > 0) { 587 if (count > pmp->pm_freeclustercount) 588 return (ENOSPC); 589 error = extendfile(dep, count, NULL, NULL, DE_CLEAR); 590 if (error) { 591 /* truncate the added clusters away again */ 592 (void) detrunc(dep, dep->de_FileSize, 0, cred, NULL); 593 return (error); 594 } 595 } 596 dep->de_FileSize = length; 597 dep->de_flag |= DE_UPDATE|DE_MODIFIED; 598 return (deupdat(dep, 1)); 599 } 600 601 /* 602 * Move a denode to its correct hash queue after the file it represents has 603 * been moved to a new directory. 604 */ 605 void 606 reinsert(dep) 607 struct denode *dep; 608 { 609 /* 610 * Fix up the denode cache. If the denode is for a directory, 611 * there is nothing to do since the hash is based on the starting 612 * cluster of the directory file and that hasn't changed. If for a 613 * file the hash is based on the location of the directory entry, 614 * so we must remove it from the cache and re-enter it with the 615 * hash based on the new location of the directory entry. 616 */ 617 if (dep->de_Attributes & ATTR_DIRECTORY) 618 return; 619 msdosfs_hashrem(dep); 620 msdosfs_hashins(dep); 621 } 622 623 int 624 msdosfs_reclaim(ap) 625 struct vop_reclaim_args /* { 626 struct vnode *a_vp; 627 } */ *ap; 628 { 629 struct vnode *vp = ap->a_vp; 630 struct denode *dep = VTODE(vp); 631 632 #ifdef MSDOSFS_DEBUG 633 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n", 634 dep, dep->de_Name, dep->de_refcnt); 635 #endif 636 637 if (prtactive && vrefcnt(vp) != 0) 638 vprint("msdosfs_reclaim(): pushing active", vp); 639 /* 640 * Remove the denode from its hash chain. 641 */ 642 msdosfs_hashrem(dep); 643 /* 644 * Purge old data structures associated with the denode. 645 */ 646 #if 0 /* XXX */ 647 dep->de_flag = 0; 648 #endif 649 FREE(dep, M_MSDOSFSNODE); 650 vp->v_data = NULL; 651 vnode_destroy_vobject(vp); 652 653 return (0); 654 } 655 656 int 657 msdosfs_inactive(ap) 658 struct vop_inactive_args /* { 659 struct vnode *a_vp; 660 struct thread *a_td; 661 } */ *ap; 662 { 663 struct vnode *vp = ap->a_vp; 664 struct denode *dep = VTODE(vp); 665 struct thread *td = ap->a_td; 666 int error = 0; 667 668 #ifdef MSDOSFS_DEBUG 669 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]); 670 #endif 671 672 if (prtactive && vrefcnt(vp) != 0) 673 vprint("msdosfs_inactive(): pushing active", vp); 674 675 /* 676 * Ignore denodes related to stale file handles. 677 */ 678 if (dep->de_Name[0] == SLOT_DELETED) 679 goto out; 680 681 /* 682 * If the file has been deleted and it is on a read/write 683 * filesystem, then truncate the file, and mark the directory slot 684 * as empty. (This may not be necessary for the dos filesystem.) 685 */ 686 #ifdef MSDOSFS_DEBUG 687 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n", 688 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY); 689 #endif 690 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { 691 error = detrunc(dep, (u_long) 0, 0, NOCRED, td); 692 dep->de_flag |= DE_UPDATE; 693 dep->de_Name[0] = SLOT_DELETED; 694 } 695 deupdat(dep, 0); 696 697 out: 698 VOP_UNLOCK(vp, 0, td); 699 /* 700 * If we are done with the denode, reclaim it 701 * so that it can be reused immediately. 702 */ 703 #ifdef MSDOSFS_DEBUG 704 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", 705 vrefcnt(vp), dep->de_Name[0]); 706 #endif 707 if (dep->de_Name[0] == SLOT_DELETED) 708 vrecycle(vp, td); 709 return (error); 710 } 711