1 /* $Id: msdosfs_denode.c,v 1.17 1996/06/12 03:37:42 davidg Exp $ */ 2 /* $NetBSD: msdosfs_denode.c,v 1.9 1994/08/21 18:44:00 ws Exp $ */ 3 4 /*- 5 * Copyright (C) 1994 Wolfgang Solfrank. 6 * Copyright (C) 1994 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/mount.h> 54 #include <sys/malloc.h> 55 #include <sys/proc.h> 56 #include <sys/buf.h> 57 #include <sys/vnode.h> 58 #include <sys/types.h> 59 #include <sys/kernel.h> /* defines "time" */ 60 61 #include <vm/vm.h> 62 #include <vm/vm_param.h> 63 #include <vm/vm_extern.h> 64 65 #include <msdosfs/bpb.h> 66 #include <msdosfs/msdosfsmount.h> 67 #include <msdosfs/direntry.h> 68 #include <msdosfs/denode.h> 69 #include <msdosfs/fat.h> 70 71 struct denode **dehashtbl; 72 u_long dehash; /* size of hash table - 1 */ 73 #define DEHASH(dev, deno) (((dev) + (deno)) & dehash) 74 75 union _qcvt { 76 quad_t qcvt; 77 long val[2]; 78 }; 79 #define SETHIGH(q, h) { \ 80 union _qcvt tmp; \ 81 tmp.qcvt = (q); \ 82 tmp.val[_QUAD_HIGHWORD] = (h); \ 83 (q) = tmp.qcvt; \ 84 } 85 #define SETLOW(q, l) { \ 86 union _qcvt tmp; \ 87 tmp.qcvt = (q); \ 88 tmp.val[_QUAD_LOWWORD] = (l); \ 89 (q) = tmp.qcvt; \ 90 } 91 92 static struct denode * 93 msdosfs_hashget __P((dev_t dev, u_long dirclust, 94 u_long diroff)); 95 static void msdosfs_hashins __P((struct denode *dep)); 96 static void msdosfs_hashrem __P((struct denode *dep)); 97 98 int msdosfs_init() 99 { 100 dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash); 101 return 0; 102 } 103 104 static struct denode * 105 msdosfs_hashget(dev, dirclust, diroff) 106 dev_t dev; 107 u_long dirclust; 108 u_long diroff; 109 { 110 struct denode *dep; 111 112 for (;;) 113 for (dep = dehashtbl[DEHASH(dev, dirclust + diroff)];; 114 dep = dep->de_next) { 115 if (dep == NULL) 116 return NULL; 117 if (dirclust != dep->de_dirclust 118 || diroff != dep->de_diroffset 119 || dev != dep->de_dev 120 || dep->de_refcnt == 0) 121 continue; 122 if (dep->de_flag & DE_LOCKED) { 123 dep->de_flag |= DE_WANTED; 124 (void) tsleep((caddr_t)dep, PINOD, "msdhgt", 0); 125 break; 126 } 127 if (!vget(DETOV(dep), 1)) 128 return dep; 129 break; 130 } 131 /* NOTREACHED */ 132 } 133 134 static void 135 msdosfs_hashins(dep) 136 struct denode *dep; 137 { 138 struct denode **depp, *deq; 139 140 depp = &dehashtbl[DEHASH(dep->de_dev, dep->de_dirclust + dep->de_diroffset)]; 141 deq = *depp; 142 if (deq) 143 deq->de_prev = &dep->de_next; 144 dep->de_next = deq; 145 dep->de_prev = depp; 146 *depp = dep; 147 } 148 149 static void 150 msdosfs_hashrem(dep) 151 struct denode *dep; 152 { 153 struct denode *deq; 154 deq = dep->de_next; 155 if (deq) 156 deq->de_prev = dep->de_prev; 157 *dep->de_prev = deq; 158 #ifdef DIAGNOSTIC 159 dep->de_next = NULL; 160 dep->de_prev = NULL; 161 #endif 162 } 163 164 /* 165 * If deget() succeeds it returns with the gotten denode locked(). 166 * 167 * pmp - address of msdosfsmount structure of the filesystem containing 168 * the denode of interest. The pm_dev field and the address of 169 * the msdosfsmount structure are used. 170 * dirclust - which cluster bp contains, if dirclust is 0 (root directory) 171 * diroffset is relative to the beginning of the root directory, 172 * otherwise it is cluster relative. 173 * diroffset - offset past begin of cluster of denode we want 174 * direntptr - address of the direntry structure of interest. If direntptr is 175 * NULL, the block is read if necessary. 176 * depp - returns the address of the gotten denode. 177 */ 178 int 179 deget(pmp, dirclust, diroffset, direntptr, depp) 180 struct msdosfsmount *pmp; /* so we know the maj/min number */ 181 u_long dirclust; /* cluster this dir entry came from */ 182 u_long diroffset; /* index of entry within the cluster */ 183 struct direntry *direntptr; 184 struct denode **depp; /* returns the addr of the gotten denode */ 185 { 186 int error; 187 dev_t dev = pmp->pm_dev; 188 struct mount *mntp = pmp->pm_mountp; 189 struct denode *ldep; 190 struct vnode *nvp; 191 struct buf *bp; 192 193 #ifdef MSDOSFS_DEBUG 194 printf("deget(pmp %p, dirclust %ld, diroffset %x, direntptr %p, depp %p)\n", 195 pmp, dirclust, diroffset, direntptr, depp); 196 #endif 197 198 /* 199 * If dir entry is given and refers to a directory, convert to 200 * canonical form 201 */ 202 if (direntptr && (direntptr->deAttributes & ATTR_DIRECTORY)) { 203 dirclust = getushort(direntptr->deStartCluster); 204 if (dirclust == MSDOSFSROOT) 205 diroffset = MSDOSFSROOT_OFS; 206 else 207 diroffset = 0; 208 } 209 210 /* 211 * See if the denode is in the denode cache. Use the location of 212 * the directory entry to compute the hash value. For subdir use 213 * address of "." entry. for root dir use cluster MSDOSFSROOT, 214 * offset MSDOSFSROOT_OFS 215 * 216 * NOTE: The check for de_refcnt > 0 below insures the denode being 217 * examined does not represent an unlinked but still open file. 218 * These files are not to be accessible even when the directory 219 * entry that represented the file happens to be reused while the 220 * deleted file is still open. 221 */ 222 ldep = msdosfs_hashget(dev, dirclust, diroffset); 223 if (ldep) { 224 *depp = ldep; 225 return 0; 226 } 227 228 /* 229 * Do the MALLOC before the getnewvnode since doing so afterward 230 * might cause a bogus v_data pointer to get dereferenced 231 * elsewhere if MALLOC should block. 232 */ 233 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK); 234 235 /* 236 * Directory entry was not in cache, have to create a vnode and 237 * copy it from the passed disk buffer. 238 */ 239 /* getnewvnode() does a VREF() on the vnode */ 240 error = getnewvnode(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp); 241 if (error) { 242 *depp = NULL; 243 FREE(ldep, M_MSDOSFSNODE); 244 return error; 245 } 246 bzero((caddr_t)ldep, sizeof *ldep); 247 nvp->v_data = ldep; 248 ldep->de_vnode = nvp; 249 ldep->de_flag = 0; 250 ldep->de_devvp = 0; 251 ldep->de_lockf = 0; 252 ldep->de_dev = dev; 253 ldep->de_dirclust = dirclust; 254 ldep->de_diroffset = diroffset; 255 fc_purge(ldep, 0); /* init the fat cache for this denode */ 256 257 /* 258 * Insert the denode into the hash queue and lock the denode so it 259 * can't be accessed until we've read it in and have done what we 260 * need to it. 261 */ 262 VOP_LOCK(nvp); 263 msdosfs_hashins(ldep); 264 265 /* 266 * Copy the directory entry into the denode area of the vnode. 267 */ 268 if (dirclust == MSDOSFSROOT && diroffset == MSDOSFSROOT_OFS) { 269 /* 270 * Directory entry for the root directory. There isn't one, 271 * so we manufacture one. We should probably rummage 272 * through the root directory and find a label entry (if it 273 * exists), and then use the time and date from that entry 274 * as the time and date for the root denode. 275 */ 276 ldep->de_Attributes = ATTR_DIRECTORY; 277 ldep->de_StartCluster = MSDOSFSROOT; 278 ldep->de_FileSize = pmp->pm_rootdirsize * pmp->pm_BytesPerSec; 279 /* 280 * fill in time and date so that dos2unixtime() doesn't 281 * spit up when called from msdosfs_getattr() with root 282 * denode 283 */ 284 ldep->de_Time = 0x0000; /* 00:00:00 */ 285 ldep->de_Date = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT) 286 | (1 << DD_DAY_SHIFT); 287 /* Jan 1, 1980 */ 288 /* leave the other fields as garbage */ 289 } else { 290 bp = NULL; 291 if (!direntptr) { 292 error = readep(pmp, dirclust, diroffset, &bp, 293 &direntptr); 294 if (error) 295 return error; 296 } 297 DE_INTERNALIZE(ldep, direntptr); 298 if (bp) 299 brelse(bp); 300 } 301 302 /* 303 * Fill in a few fields of the vnode and finish filling in the 304 * denode. Then return the address of the found denode. 305 */ 306 ldep->de_pmp = pmp; 307 ldep->de_devvp = pmp->pm_devvp; 308 ldep->de_refcnt = 1; 309 if (ldep->de_Attributes & ATTR_DIRECTORY) { 310 /* 311 * Since DOS directory entries that describe directories 312 * have 0 in the filesize field, we take this opportunity 313 * to find out the length of the directory and plug it into 314 * the denode structure. 315 */ 316 u_long size; 317 318 nvp->v_type = VDIR; 319 if (ldep->de_StartCluster == MSDOSFSROOT) 320 nvp->v_flag |= VROOT; 321 else { 322 error = pcbmap(ldep, 0xffff, 0, &size); 323 if (error == E2BIG) { 324 ldep->de_FileSize = size << pmp->pm_cnshift; 325 error = 0; 326 } else 327 printf("deget(): pcbmap returned %d\n", error); 328 } 329 } else 330 nvp->v_type = VREG; 331 SETHIGH(ldep->de_modrev, mono_time.tv_sec); 332 SETLOW(ldep->de_modrev, mono_time.tv_usec * 4294); 333 VREF(ldep->de_devvp); 334 *depp = ldep; 335 return 0; 336 } 337 338 int 339 deupdat(dep, tp, waitfor) 340 struct denode *dep; 341 struct timespec *tp; 342 int waitfor; 343 { 344 int error; 345 struct buf *bp; 346 struct direntry *dirp; 347 struct vnode *vp = DETOV(dep); 348 349 #ifdef MSDOSFS_DEBUG 350 printf("deupdat(): dep %p\n", dep); 351 #endif 352 353 /* 354 * If the denode-modified and update-mtime bits are off, 355 * or this denode is from a readonly filesystem, 356 * or this denode is for a directory, 357 * or the denode represents an open but unlinked file, 358 * then don't do anything. DOS directory 359 * entries that describe a directory do not ever get 360 * updated. This is the way DOS treats them. 361 */ 362 if ((dep->de_flag & (DE_MODIFIED | DE_UPDATE)) == 0 || 363 vp->v_mount->mnt_flag & MNT_RDONLY || 364 dep->de_Attributes & ATTR_DIRECTORY || 365 dep->de_refcnt <= 0) 366 return 0; 367 368 /* 369 * Read in the cluster containing the directory entry we want to 370 * update. 371 */ 372 error = readde(dep, &bp, &dirp); 373 if (error) 374 return error; 375 376 /* 377 * If the mtime is to be updated, put the passed in time into the 378 * directory entry. 379 */ 380 if (dep->de_flag & DE_UPDATE) { 381 dep->de_Attributes |= ATTR_ARCHIVE; 382 unix2dostime(tp, &dep->de_Date, &dep->de_Time); 383 } 384 385 /* 386 * The mtime is now up to date. The denode will be unmodifed soon. 387 */ 388 dep->de_flag &= ~(DE_MODIFIED | DE_UPDATE); 389 390 /* 391 * Copy the directory entry out of the denode into the cluster it 392 * came from. 393 */ 394 DE_EXTERNALIZE(dirp, dep); 395 396 /* 397 * Write the cluster back to disk. If they asked for us to wait 398 * for the write to complete, then use bwrite() otherwise use 399 * bdwrite(). 400 */ 401 error = 0; /* note that error is 0 from above, but ... */ 402 if (waitfor) 403 error = bwrite(bp); 404 else 405 bdwrite(bp); 406 return error; 407 } 408 409 /* 410 * Truncate the file described by dep to the length specified by length. 411 */ 412 int 413 detrunc(dep, length, flags, cred, p) 414 struct denode *dep; 415 u_long length; 416 int flags; 417 struct ucred *cred; 418 struct proc *p; 419 { 420 int error; 421 int allerror; 422 int vflags; 423 u_long eofentry; 424 u_long chaintofree; 425 daddr_t bn; 426 int boff; 427 int isadir = dep->de_Attributes & ATTR_DIRECTORY; 428 struct buf *bp; 429 struct msdosfsmount *pmp = dep->de_pmp; 430 struct timespec ts; 431 432 #ifdef MSDOSFS_DEBUG 433 printf("detrunc(): file %s, length %d, flags %d\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_flag & VROOT) { 445 printf( 446 "detrunc(): can't truncate root directory, clust %ld, offset %ld\n", 447 dep->de_dirclust, dep->de_diroffset); 448 return EINVAL; 449 } 450 451 452 if (dep->de_FileSize < length) { 453 vnode_pager_setsize(DETOV(dep), length); 454 return deextend(dep, length, cred); 455 } 456 457 /* 458 * If the desired length is 0 then remember the starting cluster of 459 * the file and set the StartCluster field in the directory entry 460 * to 0. If the desired length is not zero, then get the number of 461 * the last cluster in the shortened file. Then get the number of 462 * the first cluster in the part of the file that is to be freed. 463 * Then set the next cluster pointer in the last cluster of the 464 * file to CLUST_EOFE. 465 */ 466 if (length == 0) { 467 chaintofree = dep->de_StartCluster; 468 dep->de_StartCluster = 0; 469 eofentry = ~0; 470 } else { 471 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0, &eofentry); 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, (length + pmp->pm_crbomask) >> pmp->pm_cnshift); 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 /* 489 * should read from file vnode or filesystem vnode 490 * depending on if file or dir 491 */ 492 if (isadir) { 493 bn = cntobn(pmp, eofentry); 494 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, 495 NOCRED, &bp); 496 } else { 497 bn = de_blk(pmp, length); 498 #ifdef PC98 499 /* 500 * 1024 byte/sector support 501 */ 502 if (pmp->pm_BytesPerSec == 1024) 503 DETOV(dep)->v_flag |= 0x10000; 504 #endif 505 error = bread(DETOV(dep), bn, pmp->pm_bpcluster, 506 NOCRED, &bp); 507 } 508 if (error) { 509 #ifdef MSDOSFS_DEBUG 510 printf("detrunc(): bread fails %d\n", error); 511 #endif 512 return error; 513 } 514 /* 515 * is this the right place for it? 516 */ 517 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff); 518 if (flags & IO_SYNC) 519 bwrite(bp); 520 else 521 bdwrite(bp); 522 } 523 524 /* 525 * Write out the updated directory entry. Even if the update fails 526 * we free the trailing clusters. 527 */ 528 dep->de_FileSize = length; 529 dep->de_flag |= DE_UPDATE; 530 vflags = (length > 0 ? V_SAVE : 0) | V_SAVEMETA; 531 vinvalbuf(DETOV(dep), vflags, cred, p, 0, 0); 532 vnode_pager_setsize(DETOV(dep), length); 533 TIMEVAL_TO_TIMESPEC(&time, &ts); 534 allerror = deupdat(dep, &ts, 1); 535 #ifdef MSDOSFS_DEBUG 536 printf("detrunc(): allerror %d, eofentry %d\n", 537 allerror, eofentry); 538 #endif 539 540 /* 541 * If we need to break the cluster chain for the file then do it 542 * now. 543 */ 544 if (eofentry != ~0) { 545 error = fatentry(FAT_GET_AND_SET, pmp, eofentry, 546 &chaintofree, CLUST_EOFE); 547 if (error) { 548 #ifdef MSDOSFS_DEBUG 549 printf("detrunc(): fatentry errors %d\n", error); 550 #endif 551 return error; 552 } 553 fc_setcache(dep, FC_LASTFC, (length - 1) >> pmp->pm_cnshift, 554 eofentry); 555 } 556 557 /* 558 * Now free the clusters removed from the file because of the 559 * truncation. 560 */ 561 if (chaintofree != 0 && !MSDOSFSEOF(chaintofree)) 562 freeclusterchain(pmp, chaintofree); 563 564 return allerror; 565 } 566 567 /* 568 * Extend the file described by dep to length specified by length. 569 */ 570 int 571 deextend(dep, length, cred) 572 struct denode *dep; 573 off_t length; 574 struct ucred *cred; 575 { 576 struct msdosfsmount *pmp = dep->de_pmp; 577 u_long count; 578 int error; 579 struct timespec ts; 580 581 /* 582 * The root of a DOS filesystem cannot be extended. 583 */ 584 if (DETOV(dep)->v_flag & VROOT) 585 return EINVAL; 586 587 /* 588 * Directories can only be extended by the superuser. 589 * Is this really important? 590 */ 591 if (dep->de_Attributes & ATTR_DIRECTORY) { 592 error = suser(cred, NULL); 593 if (error) 594 return error; 595 } 596 597 if (length <= dep->de_FileSize) 598 panic("deextend: file too large"); 599 600 /* 601 * Compute the number of clusters to allocate. 602 */ 603 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize); 604 if (count > 0) { 605 if (count > pmp->pm_freeclustercount) 606 return ENOSPC; 607 error = extendfile(dep, count, NULL, NULL, DE_CLEAR); 608 if (error) { 609 /* truncate the added clusters away again */ 610 (void) detrunc(dep, dep->de_FileSize, 0, cred, NULL); 611 return error; 612 } 613 } 614 615 dep->de_flag |= DE_UPDATE; 616 dep->de_FileSize = length; 617 TIMEVAL_TO_TIMESPEC(&time, &ts); 618 return deupdat(dep, &ts, 1); 619 } 620 621 /* 622 * Move a denode to its correct hash queue after the file it represents has 623 * been moved to a new directory. 624 */ 625 int reinsert(dep) 626 struct denode *dep; 627 { 628 /* 629 * Fix up the denode cache. If the denode is for a directory, 630 * there is nothing to do since the hash is based on the starting 631 * cluster of the directory file and that hasn't changed. If for a 632 * file the hash is based on the location of the directory entry, 633 * so we must remove it from the cache and re-enter it with the 634 * hash based on the new location of the directory entry. 635 */ 636 if ((dep->de_Attributes & ATTR_DIRECTORY) == 0) { 637 msdosfs_hashrem(dep); 638 msdosfs_hashins(dep); 639 } 640 return 0; 641 } 642 643 int 644 msdosfs_reclaim(ap) 645 struct vop_reclaim_args /* { 646 struct vnode *a_vp; 647 } */ *ap; 648 { 649 struct vnode *vp = ap->a_vp; 650 struct denode *dep = VTODE(vp); 651 652 #ifdef MSDOSFS_DEBUG 653 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n", 654 dep, dep->de_Name, dep->de_refcnt); 655 #endif 656 657 if (prtactive && vp->v_usecount != 0) 658 vprint("msdosfs_reclaim(): pushing active", vp); 659 660 /* 661 * Remove the denode from the denode hash chain we are in. 662 */ 663 msdosfs_hashrem(dep); 664 665 cache_purge(vp); 666 /* 667 * Indicate that one less file on the filesystem is open. 668 */ 669 if (dep->de_devvp) { 670 vrele(dep->de_devvp); 671 dep->de_devvp = 0; 672 } 673 674 dep->de_flag = 0; 675 676 FREE(dep, M_MSDOSFSNODE); 677 vp->v_data = NULL; 678 679 return 0; 680 } 681 682 int 683 msdosfs_inactive(ap) 684 struct vop_inactive_args /* { 685 struct vnode *a_vp; 686 } */ *ap; 687 { 688 struct vnode *vp = ap->a_vp; 689 struct denode *dep = VTODE(vp); 690 int error = 0; 691 struct timespec ts; 692 693 #ifdef MSDOSFS_DEBUG 694 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]); 695 #endif 696 697 if (prtactive && vp->v_usecount != 0) 698 vprint("msdosfs_inactive(): pushing active", vp); 699 700 /* 701 * Get rid of denodes related to stale file handles. Hmmm, what 702 * does this really do? 703 */ 704 if (dep->de_Name[0] == SLOT_DELETED) { 705 if ((vp->v_flag & VXLOCK) == 0) 706 vgone(vp); 707 return 0; 708 } 709 710 /* 711 * If the file has been deleted and it is on a read/write 712 * filesystem, then truncate the file, and mark the directory slot 713 * as empty. (This may not be necessary for the dos filesystem.) 714 */ 715 #ifdef MSDOSFS_DEBUG 716 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n", 717 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY); 718 #endif 719 VOP_LOCK(vp); 720 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { 721 error = detrunc(dep, (u_long) 0, 0, NOCRED, NULL); 722 dep->de_flag |= DE_UPDATE; 723 dep->de_Name[0] = SLOT_DELETED; 724 } 725 if (dep->de_flag & (DE_MODIFIED | DE_UPDATE)) { 726 TIMEVAL_TO_TIMESPEC(&time, &ts); 727 deupdat(dep, &ts, 0); 728 } 729 VOP_UNLOCK(vp); 730 dep->de_flag = 0; 731 732 /* 733 * If we are done with the denode, then reclaim it so that it can 734 * be reused now. 735 */ 736 #ifdef MSDOSFS_DEBUG 737 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vp->v_usecount, 738 dep->de_Name[0]); 739 #endif 740 if (vp->v_usecount == 0 && dep->de_Name[0] == SLOT_DELETED) 741 vgone(vp); 742 return error; 743 } 744