1 /* $FreeBSD$ */ 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(vfsp) 99 struct vfsconf *vfsp; 100 { 101 dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash); 102 return 0; 103 } 104 105 static struct denode * 106 msdosfs_hashget(dev, dirclust, diroff) 107 dev_t dev; 108 u_long dirclust; 109 u_long diroff; 110 { 111 struct denode *dep; 112 113 for (;;) 114 for (dep = dehashtbl[DEHASH(dev, dirclust + diroff)];; 115 dep = dep->de_next) { 116 if (dep == NULL) 117 return NULL; 118 if (dirclust != dep->de_dirclust 119 || diroff != dep->de_diroffset 120 || dev != dep->de_dev 121 || dep->de_refcnt == 0) 122 continue; 123 if (dep->de_flag & DE_LOCKED) { 124 dep->de_flag |= DE_WANTED; 125 (void) tsleep((caddr_t)dep, PINOD, "msdhgt", 0); 126 break; 127 } 128 if (!vget(DETOV(dep), LK_EXCLUSIVE | LK_INTERLOCK, curproc)) 129 return dep; 130 break; 131 } 132 /* NOTREACHED */ 133 } 134 135 static void 136 msdosfs_hashins(dep) 137 struct denode *dep; 138 { 139 struct denode **depp, *deq; 140 141 depp = &dehashtbl[DEHASH(dep->de_dev, dep->de_dirclust + dep->de_diroffset)]; 142 deq = *depp; 143 if (deq) 144 deq->de_prev = &dep->de_next; 145 dep->de_next = deq; 146 dep->de_prev = depp; 147 *depp = dep; 148 } 149 150 static void 151 msdosfs_hashrem(dep) 152 struct denode *dep; 153 { 154 struct denode *deq; 155 deq = dep->de_next; 156 if (deq) 157 deq->de_prev = dep->de_prev; 158 *dep->de_prev = deq; 159 #ifdef DIAGNOSTIC 160 dep->de_next = NULL; 161 dep->de_prev = NULL; 162 #endif 163 } 164 165 /* 166 * If deget() succeeds it returns with the gotten denode locked(). 167 * 168 * pmp - address of msdosfsmount structure of the filesystem containing 169 * the denode of interest. The pm_dev field and the address of 170 * the msdosfsmount structure are used. 171 * dirclust - which cluster bp contains, if dirclust is 0 (root directory) 172 * diroffset is relative to the beginning of the root directory, 173 * otherwise it is cluster relative. 174 * diroffset - offset past begin of cluster of denode we want 175 * direntptr - address of the direntry structure of interest. If direntptr is 176 * NULL, the block is read if necessary. 177 * depp - returns the address of the gotten denode. 178 */ 179 int 180 deget(pmp, dirclust, diroffset, direntptr, depp) 181 struct msdosfsmount *pmp; /* so we know the maj/min number */ 182 u_long dirclust; /* cluster this dir entry came from */ 183 u_long diroffset; /* index of entry within the cluster */ 184 struct direntry *direntptr; 185 struct denode **depp; /* returns the addr of the gotten denode */ 186 { 187 int error; 188 dev_t dev = pmp->pm_dev; 189 struct mount *mntp = pmp->pm_mountp; 190 struct denode *ldep; 191 struct vnode *nvp; 192 struct buf *bp; 193 194 #ifdef MSDOSFS_DEBUG 195 printf("deget(pmp %p, dirclust %ld, diroffset %x, direntptr %p, depp %p)\n", 196 pmp, dirclust, diroffset, direntptr, depp); 197 #endif 198 199 /* 200 * If dir entry is given and refers to a directory, convert to 201 * canonical form 202 */ 203 if (direntptr && (direntptr->deAttributes & ATTR_DIRECTORY)) { 204 dirclust = getushort(direntptr->deStartCluster); 205 if (dirclust == MSDOSFSROOT) 206 diroffset = MSDOSFSROOT_OFS; 207 else 208 diroffset = 0; 209 } 210 211 /* 212 * See if the denode is in the denode cache. Use the location of 213 * the directory entry to compute the hash value. For subdir use 214 * address of "." entry. for root dir use cluster MSDOSFSROOT, 215 * offset MSDOSFSROOT_OFS 216 * 217 * NOTE: The check for de_refcnt > 0 below insures the denode being 218 * examined does not represent an unlinked but still open file. 219 * These files are not to be accessible even when the directory 220 * entry that represented the file happens to be reused while the 221 * deleted file is still open. 222 */ 223 ldep = msdosfs_hashget(dev, dirclust, diroffset); 224 if (ldep) { 225 *depp = ldep; 226 return 0; 227 } 228 229 /* 230 * Do the MALLOC before the getnewvnode since doing so afterward 231 * might cause a bogus v_data pointer to get dereferenced 232 * elsewhere if MALLOC should block. 233 */ 234 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK); 235 236 /* 237 * Directory entry was not in cache, have to create a vnode and 238 * copy it from the passed disk buffer. 239 */ 240 /* getnewvnode() does a VREF() on the vnode */ 241 error = getnewvnode(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp); 242 if (error) { 243 *depp = NULL; 244 FREE(ldep, M_MSDOSFSNODE); 245 return error; 246 } 247 bzero((caddr_t)ldep, sizeof *ldep); 248 nvp->v_data = ldep; 249 ldep->de_vnode = nvp; 250 ldep->de_flag = 0; 251 ldep->de_devvp = 0; 252 ldep->de_lockf = 0; 253 ldep->de_dev = dev; 254 ldep->de_dirclust = dirclust; 255 ldep->de_diroffset = diroffset; 256 fc_purge(ldep, 0); /* init the fat cache for this denode */ 257 258 /* 259 * Insert the denode into the hash queue and lock the denode so it 260 * can't be accessed until we've read it in and have done what we 261 * need to it. 262 */ 263 vn_lock(nvp, LK_EXCLUSIVE | LK_RETRY, curproc); 264 msdosfs_hashins(ldep); 265 266 /* 267 * Copy the directory entry into the denode area of the vnode. 268 */ 269 if (dirclust == MSDOSFSROOT && diroffset == MSDOSFSROOT_OFS) { 270 /* 271 * Directory entry for the root directory. There isn't one, 272 * so we manufacture one. We should probably rummage 273 * through the root directory and find a label entry (if it 274 * exists), and then use the time and date from that entry 275 * as the time and date for the root denode. 276 */ 277 ldep->de_Attributes = ATTR_DIRECTORY; 278 ldep->de_StartCluster = MSDOSFSROOT; 279 ldep->de_FileSize = pmp->pm_rootdirsize * pmp->pm_BytesPerSec; 280 /* 281 * fill in time and date so that dos2unixtime() doesn't 282 * spit up when called from msdosfs_getattr() with root 283 * denode 284 */ 285 ldep->de_Time = 0x0000; /* 00:00:00 */ 286 ldep->de_Date = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT) 287 | (1 << DD_DAY_SHIFT); 288 /* Jan 1, 1980 */ 289 /* leave the other fields as garbage */ 290 } else { 291 bp = NULL; 292 if (!direntptr) { 293 error = readep(pmp, dirclust, diroffset, &bp, 294 &direntptr); 295 if (error) 296 return error; 297 } 298 DE_INTERNALIZE(ldep, direntptr); 299 if (bp) 300 brelse(bp); 301 } 302 303 /* 304 * Fill in a few fields of the vnode and finish filling in the 305 * denode. Then return the address of the found denode. 306 */ 307 ldep->de_pmp = pmp; 308 ldep->de_devvp = pmp->pm_devvp; 309 ldep->de_refcnt = 1; 310 if (ldep->de_Attributes & ATTR_DIRECTORY) { 311 /* 312 * Since DOS directory entries that describe directories 313 * have 0 in the filesize field, we take this opportunity 314 * to find out the length of the directory and plug it into 315 * the denode structure. 316 */ 317 u_long size; 318 319 nvp->v_type = VDIR; 320 if (ldep->de_StartCluster == MSDOSFSROOT) 321 nvp->v_flag |= VROOT; 322 else { 323 error = pcbmap(ldep, 0xffff, 0, &size); 324 if (error == E2BIG) { 325 ldep->de_FileSize = size << pmp->pm_cnshift; 326 error = 0; 327 } else 328 printf("deget(): pcbmap returned %d\n", error); 329 } 330 } else 331 nvp->v_type = VREG; 332 SETHIGH(ldep->de_modrev, mono_time.tv_sec); 333 SETLOW(ldep->de_modrev, mono_time.tv_usec * 4294); 334 VREF(ldep->de_devvp); 335 *depp = ldep; 336 return 0; 337 } 338 339 int 340 deupdat(dep, tp, waitfor) 341 struct denode *dep; 342 struct timespec *tp; 343 int waitfor; 344 { 345 int error; 346 struct buf *bp; 347 struct direntry *dirp; 348 struct vnode *vp = DETOV(dep); 349 350 #ifdef MSDOSFS_DEBUG 351 printf("deupdat(): dep %p\n", dep); 352 #endif 353 354 /* 355 * If the denode-modified and update-mtime bits are off, 356 * or this denode is from a readonly filesystem, 357 * or this denode is for a directory, 358 * or the denode represents an open but unlinked file, 359 * then don't do anything. DOS directory 360 * entries that describe a directory do not ever get 361 * updated. This is the way DOS treats them. 362 */ 363 if ((dep->de_flag & (DE_MODIFIED | DE_UPDATE)) == 0 || 364 vp->v_mount->mnt_flag & MNT_RDONLY || 365 dep->de_Attributes & ATTR_DIRECTORY || 366 dep->de_refcnt <= 0) 367 return 0; 368 369 /* 370 * Read in the cluster containing the directory entry we want to 371 * update. 372 */ 373 error = readde(dep, &bp, &dirp); 374 if (error) 375 return error; 376 377 /* 378 * If the mtime is to be updated, put the passed in time into the 379 * directory entry. 380 */ 381 if (dep->de_flag & DE_UPDATE) { 382 dep->de_Attributes |= ATTR_ARCHIVE; 383 unix2dostime(tp, &dep->de_Date, &dep->de_Time); 384 } 385 386 /* 387 * The mtime is now up to date. The denode will be unmodifed soon. 388 */ 389 dep->de_flag &= ~(DE_MODIFIED | DE_UPDATE); 390 391 /* 392 * Copy the directory entry out of the denode into the cluster it 393 * came from. 394 */ 395 DE_EXTERNALIZE(dirp, dep); 396 397 /* 398 * Write the cluster back to disk. If they asked for us to wait 399 * for the write to complete, then use bwrite() otherwise use 400 * bdwrite(). 401 */ 402 error = 0; /* note that error is 0 from above, but ... */ 403 if (waitfor) 404 error = bwrite(bp); 405 else 406 bdwrite(bp); 407 return error; 408 } 409 410 /* 411 * Truncate the file described by dep to the length specified by length. 412 */ 413 int 414 detrunc(dep, length, flags, cred, p) 415 struct denode *dep; 416 u_long length; 417 int flags; 418 struct ucred *cred; 419 struct proc *p; 420 { 421 int error; 422 int allerror; 423 int vflags; 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 struct timespec ts; 432 433 #ifdef MSDOSFS_DEBUG 434 printf("detrunc(): file %s, length %d, flags %d\n", dep->de_Name, length, flags); 435 #endif 436 437 /* 438 * Disallow attempts to truncate the root directory since it is of 439 * fixed size. That's just the way dos filesystems are. We use 440 * the VROOT bit in the vnode because checking for the directory 441 * bit and a startcluster of 0 in the denode is not adequate to 442 * recognize the root directory at this point in a file or 443 * directory's life. 444 */ 445 if (DETOV(dep)->v_flag & VROOT) { 446 printf( 447 "detrunc(): can't truncate root directory, clust %ld, offset %ld\n", 448 dep->de_dirclust, dep->de_diroffset); 449 return EINVAL; 450 } 451 452 453 if (dep->de_FileSize < length) { 454 vnode_pager_setsize(DETOV(dep), length); 455 return deextend(dep, length, cred); 456 } 457 458 /* 459 * If the desired length is 0 then remember the starting cluster of 460 * the file and set the StartCluster field in the directory entry 461 * to 0. If the desired length is not zero, then get the number of 462 * the last cluster in the shortened file. Then get the number of 463 * the first cluster in the part of the file that is to be freed. 464 * Then set the next cluster pointer in the last cluster of the 465 * file to CLUST_EOFE. 466 */ 467 if (length == 0) { 468 chaintofree = dep->de_StartCluster; 469 dep->de_StartCluster = 0; 470 eofentry = ~0; 471 } else { 472 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0, &eofentry); 473 if (error) { 474 #ifdef MSDOSFS_DEBUG 475 printf("detrunc(): pcbmap fails %d\n", error); 476 #endif 477 return error; 478 } 479 } 480 481 fc_purge(dep, (length + pmp->pm_crbomask) >> pmp->pm_cnshift); 482 483 /* 484 * If the new length is not a multiple of the cluster size then we 485 * must zero the tail end of the new last cluster in case it 486 * becomes part of the file again because of a seek. 487 */ 488 if ((boff = length & pmp->pm_crbomask) != 0) { 489 /* 490 * should read from file vnode or filesystem vnode 491 * depending on if file or dir 492 */ 493 if (isadir) { 494 bn = cntobn(pmp, eofentry); 495 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, 496 NOCRED, &bp); 497 } else { 498 bn = de_blk(pmp, length); 499 #ifdef PC98 500 /* 501 * 1024 byte/sector support 502 */ 503 if (pmp->pm_BytesPerSec == 1024) 504 DETOV(dep)->v_flag |= 0x10000; 505 #endif 506 error = bread(DETOV(dep), bn, pmp->pm_bpcluster, 507 NOCRED, &bp); 508 } 509 if (error) { 510 #ifdef MSDOSFS_DEBUG 511 printf("detrunc(): bread fails %d\n", error); 512 #endif 513 return error; 514 } 515 /* 516 * is this the right place for it? 517 */ 518 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff); 519 if (flags & IO_SYNC) 520 bwrite(bp); 521 else 522 bdwrite(bp); 523 } 524 525 /* 526 * Write out the updated directory entry. Even if the update fails 527 * we free the trailing clusters. 528 */ 529 dep->de_FileSize = length; 530 dep->de_flag |= DE_UPDATE; 531 vflags = (length > 0 ? V_SAVE : 0) | V_SAVEMETA; 532 vinvalbuf(DETOV(dep), vflags, cred, p, 0, 0); 533 vnode_pager_setsize(DETOV(dep), length); 534 TIMEVAL_TO_TIMESPEC(&time, &ts); 535 allerror = deupdat(dep, &ts, 1); 536 #ifdef MSDOSFS_DEBUG 537 printf("detrunc(): allerror %d, eofentry %d\n", 538 allerror, eofentry); 539 #endif 540 541 /* 542 * If we need to break the cluster chain for the file then do it 543 * now. 544 */ 545 if (eofentry != ~0) { 546 error = fatentry(FAT_GET_AND_SET, pmp, eofentry, 547 &chaintofree, CLUST_EOFE); 548 if (error) { 549 #ifdef MSDOSFS_DEBUG 550 printf("detrunc(): fatentry errors %d\n", error); 551 #endif 552 return error; 553 } 554 fc_setcache(dep, FC_LASTFC, (length - 1) >> pmp->pm_cnshift, 555 eofentry); 556 } 557 558 /* 559 * Now free the clusters removed from the file because of the 560 * truncation. 561 */ 562 if (chaintofree != 0 && !MSDOSFSEOF(chaintofree)) 563 freeclusterchain(pmp, chaintofree); 564 565 return allerror; 566 } 567 568 /* 569 * Extend the file described by dep to length specified by length. 570 */ 571 int 572 deextend(dep, length, cred) 573 struct denode *dep; 574 off_t length; 575 struct ucred *cred; 576 { 577 struct msdosfsmount *pmp = dep->de_pmp; 578 u_long count; 579 int error; 580 struct timespec ts; 581 582 /* 583 * The root of a DOS filesystem cannot be extended. 584 */ 585 if (DETOV(dep)->v_flag & VROOT) 586 return EINVAL; 587 588 /* 589 * Directories can only be extended by the superuser. 590 * Is this really important? 591 */ 592 if (dep->de_Attributes & ATTR_DIRECTORY) { 593 error = suser(cred, NULL); 594 if (error) 595 return error; 596 } 597 598 if (length <= dep->de_FileSize) 599 panic("deextend: file too large"); 600 601 /* 602 * Compute the number of clusters to allocate. 603 */ 604 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize); 605 if (count > 0) { 606 if (count > pmp->pm_freeclustercount) 607 return ENOSPC; 608 error = extendfile(dep, count, NULL, NULL, DE_CLEAR); 609 if (error) { 610 /* truncate the added clusters away again */ 611 (void) detrunc(dep, dep->de_FileSize, 0, cred, NULL); 612 return error; 613 } 614 } 615 616 dep->de_flag |= DE_UPDATE; 617 dep->de_FileSize = length; 618 TIMEVAL_TO_TIMESPEC(&time, &ts); 619 return deupdat(dep, &ts, 1); 620 } 621 622 /* 623 * Move a denode to its correct hash queue after the file it represents has 624 * been moved to a new directory. 625 */ 626 int reinsert(dep) 627 struct denode *dep; 628 { 629 /* 630 * Fix up the denode cache. If the denode is for a directory, 631 * there is nothing to do since the hash is based on the starting 632 * cluster of the directory file and that hasn't changed. If for a 633 * file the hash is based on the location of the directory entry, 634 * so we must remove it from the cache and re-enter it with the 635 * hash based on the new location of the directory entry. 636 */ 637 if ((dep->de_Attributes & ATTR_DIRECTORY) == 0) { 638 msdosfs_hashrem(dep); 639 msdosfs_hashins(dep); 640 } 641 return 0; 642 } 643 644 int 645 msdosfs_reclaim(ap) 646 struct vop_reclaim_args /* { 647 struct vnode *a_vp; 648 } */ *ap; 649 { 650 struct vnode *vp = ap->a_vp; 651 struct denode *dep = VTODE(vp); 652 653 #ifdef MSDOSFS_DEBUG 654 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n", 655 dep, dep->de_Name, dep->de_refcnt); 656 #endif 657 658 if (prtactive && vp->v_usecount != 0) 659 vprint("msdosfs_reclaim(): pushing active", vp); 660 661 /* 662 * Remove the denode from the denode hash chain we are in. 663 */ 664 msdosfs_hashrem(dep); 665 666 cache_purge(vp); 667 /* 668 * Indicate that one less file on the filesystem is open. 669 */ 670 if (dep->de_devvp) { 671 vrele(dep->de_devvp); 672 dep->de_devvp = 0; 673 } 674 675 dep->de_flag = 0; 676 677 FREE(dep, M_MSDOSFSNODE); 678 vp->v_data = NULL; 679 680 return 0; 681 } 682 683 int 684 msdosfs_inactive(ap) 685 struct vop_inactive_args /* { 686 struct vnode *a_vp; 687 } */ *ap; 688 { 689 struct vnode *vp = ap->a_vp; 690 struct denode *dep = VTODE(vp); 691 int error = 0; 692 struct timespec ts; 693 694 #ifdef MSDOSFS_DEBUG 695 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]); 696 #endif 697 698 if (prtactive && vp->v_usecount != 0) 699 vprint("msdosfs_inactive(): pushing active", vp); 700 701 /* 702 * Get rid of denodes related to stale file handles. Hmmm, what 703 * does this really do? 704 */ 705 if (dep->de_Name[0] == SLOT_DELETED) { 706 if ((vp->v_flag & VXLOCK) == 0) 707 vgone(vp); 708 return 0; 709 } 710 711 /* 712 * If the file has been deleted and it is on a read/write 713 * filesystem, then truncate the file, and mark the directory slot 714 * as empty. (This may not be necessary for the dos filesystem.) 715 */ 716 #ifdef MSDOSFS_DEBUG 717 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n", 718 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY); 719 #endif 720 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, curproc); 721 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { 722 error = detrunc(dep, (u_long) 0, 0, NOCRED, NULL); 723 dep->de_flag |= DE_UPDATE; 724 dep->de_Name[0] = SLOT_DELETED; 725 } 726 if (dep->de_flag & (DE_MODIFIED | DE_UPDATE)) { 727 TIMEVAL_TO_TIMESPEC(&time, &ts); 728 deupdat(dep, &ts, 0); 729 } 730 VOP_UNLOCK(vp, 0, curproc); 731 dep->de_flag = 0; 732 733 /* 734 * If we are done with the denode, then reclaim it so that it can 735 * be reused now. 736 */ 737 #ifdef MSDOSFS_DEBUG 738 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vp->v_usecount, 739 dep->de_Name[0]); 740 #endif 741 if (vp->v_usecount == 0 && dep->de_Name[0] == SLOT_DELETED) 742 vgone(vp); 743 return error; 744 } 745