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 int 73 de_vncmpf(struct vnode *vp, void *arg) 74 { 75 struct denode *de; 76 uint64_t *a; 77 78 a = arg; 79 de = VTODE(vp); 80 return (de->de_inode != *a); 81 } 82 83 /* 84 * If deget() succeeds it returns with the gotten denode locked(). 85 * 86 * pmp - address of msdosfsmount structure of the filesystem containing 87 * the denode of interest. The address of 88 * the msdosfsmount structure are used. 89 * dirclust - which cluster bp contains, if dirclust is 0 (root directory) 90 * diroffset is relative to the beginning of the root directory, 91 * otherwise it is cluster relative. 92 * diroffset - offset past begin of cluster of denode we want 93 * depp - returns the address of the gotten denode. 94 */ 95 int 96 deget(pmp, dirclust, diroffset, depp) 97 struct msdosfsmount *pmp; /* so we know the maj/min number */ 98 u_long dirclust; /* cluster this dir entry came from */ 99 u_long diroffset; /* index of entry within the cluster */ 100 struct denode **depp; /* returns the addr of the gotten denode */ 101 { 102 int error; 103 uint64_t inode; 104 struct mount *mntp = pmp->pm_mountp; 105 struct direntry *direntptr; 106 struct denode *ldep; 107 struct vnode *nvp, *xvp; 108 struct buf *bp; 109 110 #ifdef MSDOSFS_DEBUG 111 printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n", 112 pmp, dirclust, diroffset, depp); 113 #endif 114 115 /* 116 * On FAT32 filesystems, root is a (more or less) normal 117 * directory 118 */ 119 if (FAT32(pmp) && dirclust == MSDOSFSROOT) 120 dirclust = pmp->pm_rootdirblk; 121 122 /* 123 * See if the denode is in the denode cache. Use the location of 124 * the directory entry to compute the hash value. For subdir use 125 * address of "." entry. For root dir (if not FAT32) use cluster 126 * MSDOSFSROOT, offset MSDOSFSROOT_OFS 127 * 128 * NOTE: The check for de_refcnt > 0 below insures the denode being 129 * examined does not represent an unlinked but still open file. 130 * These files are not to be accessible even when the directory 131 * entry that represented the file happens to be reused while the 132 * deleted file is still open. 133 */ 134 inode = (uint64_t)pmp->pm_bpcluster * dirclust + diroffset; 135 136 error = vfs_hash_get(mntp, inode, LK_EXCLUSIVE, curthread, &nvp, 137 de_vncmpf, &inode); 138 if (error) 139 return(error); 140 if (nvp != NULL) { 141 *depp = VTODE(nvp); 142 KASSERT((*depp)->de_dirclust == dirclust, ("wrong dirclust")); 143 KASSERT((*depp)->de_diroffset == diroffset, ("wrong diroffset")); 144 return (0); 145 } 146 147 /* 148 * Do the MALLOC before the getnewvnode since doing so afterward 149 * might cause a bogus v_data pointer to get dereferenced 150 * elsewhere if MALLOC should block. 151 */ 152 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK); 153 154 /* 155 * Directory entry was not in cache, have to create a vnode and 156 * copy it from the passed disk buffer. 157 */ 158 /* getnewvnode() does a VREF() on the vnode */ 159 error = getnewvnode("msdosfs", mntp, &msdosfs_vnodeops, &nvp); 160 if (error) { 161 *depp = NULL; 162 FREE(ldep, M_MSDOSFSNODE); 163 return error; 164 } 165 bzero((caddr_t)ldep, sizeof *ldep); 166 nvp->v_data = ldep; 167 ldep->de_vnode = nvp; 168 ldep->de_flag = 0; 169 ldep->de_dirclust = dirclust; 170 ldep->de_diroffset = diroffset; 171 ldep->de_inode = inode; 172 fc_purge(ldep, 0); /* init the fat cache for this denode */ 173 174 error = vfs_hash_insert(nvp, inode, LK_EXCLUSIVE, curthread, &xvp, 175 de_vncmpf, &inode); 176 if (error) { 177 *depp = NULL; 178 return (error); 179 } 180 if (xvp != NULL) { 181 /* XXX: Not sure this is right */ 182 nvp = xvp; 183 ldep->de_vnode = nvp; 184 } 185 186 ldep->de_pmp = pmp; 187 ldep->de_refcnt = 1; 188 /* 189 * Copy the directory entry into the denode area of the vnode. 190 */ 191 if ((dirclust == MSDOSFSROOT 192 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk)) 193 && diroffset == MSDOSFSROOT_OFS) { 194 /* 195 * Directory entry for the root directory. There isn't one, 196 * so we manufacture one. We should probably rummage 197 * through the root directory and find a label entry (if it 198 * exists), and then use the time and date from that entry 199 * as the time and date for the root denode. 200 */ 201 nvp->v_vflag |= VV_ROOT; /* should be further down XXX */ 202 203 ldep->de_Attributes = ATTR_DIRECTORY; 204 ldep->de_LowerCase = 0; 205 if (FAT32(pmp)) 206 ldep->de_StartCluster = pmp->pm_rootdirblk; 207 /* de_FileSize will be filled in further down */ 208 else { 209 ldep->de_StartCluster = MSDOSFSROOT; 210 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE; 211 } 212 /* 213 * fill in time and date so that dos2unixtime() doesn't 214 * spit up when called from msdosfs_getattr() with root 215 * denode 216 */ 217 ldep->de_CHun = 0; 218 ldep->de_CTime = 0x0000; /* 00:00:00 */ 219 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT) 220 | (1 << DD_DAY_SHIFT); 221 /* Jan 1, 1980 */ 222 ldep->de_ADate = ldep->de_CDate; 223 ldep->de_MTime = ldep->de_CTime; 224 ldep->de_MDate = ldep->de_CDate; 225 /* leave the other fields as garbage */ 226 } else { 227 error = readep(pmp, dirclust, diroffset, &bp, &direntptr); 228 if (error) { 229 /* 230 * The denode does not contain anything useful, so 231 * it would be wrong to leave it on its hash chain. 232 * Arrange for vput() to just forget about it. 233 */ 234 ldep->de_Name[0] = SLOT_DELETED; 235 236 vput(nvp); 237 *depp = NULL; 238 return (error); 239 } 240 DE_INTERNALIZE(ldep, direntptr); 241 brelse(bp); 242 } 243 244 /* 245 * Fill in a few fields of the vnode and finish filling in the 246 * denode. Then return the address of the found denode. 247 */ 248 if (ldep->de_Attributes & ATTR_DIRECTORY) { 249 /* 250 * Since DOS directory entries that describe directories 251 * have 0 in the filesize field, we take this opportunity 252 * to find out the length of the directory and plug it into 253 * the denode structure. 254 */ 255 u_long size; 256 257 /* 258 * XXX Sometimes, these arrives that . entry have cluster 259 * number 0, when it shouldn't. Use real cluster number 260 * instead of what is written in directory entry. 261 */ 262 if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) { 263 printf("deget(): . entry at clust %ld != %ld\n", 264 dirclust, ldep->de_StartCluster); 265 ldep->de_StartCluster = dirclust; 266 } 267 268 nvp->v_type = VDIR; 269 if (ldep->de_StartCluster != MSDOSFSROOT) { 270 error = pcbmap(ldep, 0xffff, 0, &size, 0); 271 if (error == E2BIG) { 272 ldep->de_FileSize = de_cn2off(pmp, size); 273 error = 0; 274 } else 275 printf("deget(): pcbmap returned %d\n", error); 276 } 277 } else 278 nvp->v_type = VREG; 279 ldep->de_modrev = init_va_filerev(); 280 *depp = ldep; 281 return (0); 282 } 283 284 int 285 deupdat(dep, waitfor) 286 struct denode *dep; 287 int waitfor; 288 { 289 int error; 290 struct buf *bp; 291 struct direntry *dirp; 292 struct timespec ts; 293 294 if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY) 295 return (0); 296 getnanotime(&ts); 297 DETIMES(dep, &ts, &ts, &ts); 298 if ((dep->de_flag & DE_MODIFIED) == 0) 299 return (0); 300 dep->de_flag &= ~DE_MODIFIED; 301 if (dep->de_Attributes & ATTR_DIRECTORY) 302 return (0); 303 if (dep->de_refcnt <= 0) 304 return (0); 305 error = readde(dep, &bp, &dirp); 306 if (error) 307 return (error); 308 DE_EXTERNALIZE(dirp, dep); 309 if (waitfor) 310 return (bwrite(bp)); 311 else { 312 bdwrite(bp); 313 return (0); 314 } 315 } 316 317 /* 318 * Truncate the file described by dep to the length specified by length. 319 */ 320 int 321 detrunc(dep, length, flags, cred, td) 322 struct denode *dep; 323 u_long length; 324 int flags; 325 struct ucred *cred; 326 struct thread *td; 327 { 328 int error; 329 int allerror; 330 u_long eofentry; 331 u_long chaintofree; 332 daddr_t bn; 333 int boff; 334 int isadir = dep->de_Attributes & ATTR_DIRECTORY; 335 struct buf *bp; 336 struct msdosfsmount *pmp = dep->de_pmp; 337 338 #ifdef MSDOSFS_DEBUG 339 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags); 340 #endif 341 342 /* 343 * Disallow attempts to truncate the root directory since it is of 344 * fixed size. That's just the way dos filesystems are. We use 345 * the VROOT bit in the vnode because checking for the directory 346 * bit and a startcluster of 0 in the denode is not adequate to 347 * recognize the root directory at this point in a file or 348 * directory's life. 349 */ 350 if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) { 351 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n", 352 dep->de_dirclust, dep->de_diroffset); 353 return (EINVAL); 354 } 355 356 357 if (dep->de_FileSize < length) { 358 vnode_pager_setsize(DETOV(dep), length); 359 return deextend(dep, length, cred); 360 } 361 362 /* 363 * If the desired length is 0 then remember the starting cluster of 364 * the file and set the StartCluster field in the directory entry 365 * to 0. If the desired length is not zero, then get the number of 366 * the last cluster in the shortened file. Then get the number of 367 * the first cluster in the part of the file that is to be freed. 368 * Then set the next cluster pointer in the last cluster of the 369 * file to CLUST_EOFE. 370 */ 371 if (length == 0) { 372 chaintofree = dep->de_StartCluster; 373 dep->de_StartCluster = 0; 374 eofentry = ~0; 375 } else { 376 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0, 377 &eofentry, 0); 378 if (error) { 379 #ifdef MSDOSFS_DEBUG 380 printf("detrunc(): pcbmap fails %d\n", error); 381 #endif 382 return (error); 383 } 384 } 385 386 fc_purge(dep, de_clcount(pmp, length)); 387 388 /* 389 * If the new length is not a multiple of the cluster size then we 390 * must zero the tail end of the new last cluster in case it 391 * becomes part of the file again because of a seek. 392 */ 393 if ((boff = length & pmp->pm_crbomask) != 0) { 394 if (isadir) { 395 bn = cntobn(pmp, eofentry); 396 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, 397 NOCRED, &bp); 398 if (error) { 399 brelse(bp); 400 #ifdef MSDOSFS_DEBUG 401 printf("detrunc(): bread fails %d\n", error); 402 #endif 403 return (error); 404 } 405 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff); 406 if (flags & IO_SYNC) 407 bwrite(bp); 408 else 409 bdwrite(bp); 410 } 411 } 412 413 /* 414 * Write out the updated directory entry. Even if the update fails 415 * we free the trailing clusters. 416 */ 417 dep->de_FileSize = length; 418 if (!isadir) 419 dep->de_flag |= DE_UPDATE|DE_MODIFIED; 420 allerror = vtruncbuf(DETOV(dep), cred, td, length, pmp->pm_bpcluster); 421 #ifdef MSDOSFS_DEBUG 422 if (allerror) 423 printf("detrunc(): vtruncbuf error %d\n", allerror); 424 #endif 425 error = deupdat(dep, 1); 426 if (error && (allerror == 0)) 427 allerror = error; 428 #ifdef MSDOSFS_DEBUG 429 printf("detrunc(): allerror %d, eofentry %lu\n", 430 allerror, eofentry); 431 #endif 432 433 /* 434 * If we need to break the cluster chain for the file then do it 435 * now. 436 */ 437 if (eofentry != ~0) { 438 error = fatentry(FAT_GET_AND_SET, pmp, eofentry, 439 &chaintofree, CLUST_EOFE); 440 if (error) { 441 #ifdef MSDOSFS_DEBUG 442 printf("detrunc(): fatentry errors %d\n", error); 443 #endif 444 return (error); 445 } 446 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1), 447 eofentry); 448 } 449 450 /* 451 * Now free the clusters removed from the file because of the 452 * truncation. 453 */ 454 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree)) 455 freeclusterchain(pmp, chaintofree); 456 457 return (allerror); 458 } 459 460 /* 461 * Extend the file described by dep to length specified by length. 462 */ 463 int 464 deextend(dep, length, cred) 465 struct denode *dep; 466 u_long length; 467 struct ucred *cred; 468 { 469 struct msdosfsmount *pmp = dep->de_pmp; 470 u_long count; 471 int error; 472 473 /* 474 * The root of a DOS filesystem cannot be extended. 475 */ 476 if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) 477 return (EINVAL); 478 479 /* 480 * Directories cannot be extended. 481 */ 482 if (dep->de_Attributes & ATTR_DIRECTORY) 483 return (EISDIR); 484 485 if (length <= dep->de_FileSize) 486 panic("deextend: file too large"); 487 488 /* 489 * Compute the number of clusters to allocate. 490 */ 491 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize); 492 if (count > 0) { 493 if (count > pmp->pm_freeclustercount) 494 return (ENOSPC); 495 error = extendfile(dep, count, NULL, NULL, DE_CLEAR); 496 if (error) { 497 /* truncate the added clusters away again */ 498 (void) detrunc(dep, dep->de_FileSize, 0, cred, NULL); 499 return (error); 500 } 501 } 502 dep->de_FileSize = length; 503 dep->de_flag |= DE_UPDATE|DE_MODIFIED; 504 return (deupdat(dep, 1)); 505 } 506 507 /* 508 * Move a denode to its correct hash queue after the file it represents has 509 * been moved to a new directory. 510 */ 511 void 512 reinsert(dep) 513 struct denode *dep; 514 { 515 struct vnode *vp; 516 517 /* 518 * Fix up the denode cache. If the denode is for a directory, 519 * there is nothing to do since the hash is based on the starting 520 * cluster of the directory file and that hasn't changed. If for a 521 * file the hash is based on the location of the directory entry, 522 * so we must remove it from the cache and re-enter it with the 523 * hash based on the new location of the directory entry. 524 */ 525 #if 0 526 if (dep->de_Attributes & ATTR_DIRECTORY) 527 return; 528 #endif 529 vp = DETOV(dep); 530 dep->de_inode = (uint64_t)dep->de_pmp->pm_bpcluster * dep->de_dirclust + 531 dep->de_diroffset; 532 vfs_hash_rehash(vp, dep->de_inode); 533 } 534 535 int 536 msdosfs_reclaim(ap) 537 struct vop_reclaim_args /* { 538 struct vnode *a_vp; 539 } */ *ap; 540 { 541 struct vnode *vp = ap->a_vp; 542 struct denode *dep = VTODE(vp); 543 544 #ifdef MSDOSFS_DEBUG 545 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n", 546 dep, dep->de_Name, dep->de_refcnt); 547 #endif 548 549 if (prtactive && vrefcnt(vp) != 0) 550 vprint("msdosfs_reclaim(): pushing active", vp); 551 /* 552 * Destroy the vm object and flush associated pages. 553 */ 554 vnode_destroy_vobject(vp); 555 /* 556 * Remove the denode from its hash chain. 557 */ 558 vfs_hash_remove(vp); 559 /* 560 * Purge old data structures associated with the denode. 561 */ 562 #if 0 /* XXX */ 563 dep->de_flag = 0; 564 #endif 565 FREE(dep, M_MSDOSFSNODE); 566 vp->v_data = NULL; 567 568 return (0); 569 } 570 571 int 572 msdosfs_inactive(ap) 573 struct vop_inactive_args /* { 574 struct vnode *a_vp; 575 struct thread *a_td; 576 } */ *ap; 577 { 578 struct vnode *vp = ap->a_vp; 579 struct denode *dep = VTODE(vp); 580 struct thread *td = ap->a_td; 581 int error = 0; 582 583 #ifdef MSDOSFS_DEBUG 584 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]); 585 #endif 586 587 if (prtactive && vrefcnt(vp) != 0) 588 vprint("msdosfs_inactive(): pushing active", vp); 589 590 /* 591 * Ignore denodes related to stale file handles. 592 */ 593 if (dep->de_Name[0] == SLOT_DELETED) 594 goto out; 595 596 /* 597 * If the file has been deleted and it is on a read/write 598 * filesystem, then truncate the file, and mark the directory slot 599 * as empty. (This may not be necessary for the dos filesystem.) 600 */ 601 #ifdef MSDOSFS_DEBUG 602 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n", 603 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY); 604 #endif 605 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { 606 error = detrunc(dep, (u_long) 0, 0, NOCRED, td); 607 dep->de_flag |= DE_UPDATE; 608 dep->de_Name[0] = SLOT_DELETED; 609 } 610 deupdat(dep, 0); 611 612 out: 613 /* 614 * If we are done with the denode, reclaim it 615 * so that it can be reused immediately. 616 */ 617 #ifdef MSDOSFS_DEBUG 618 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", 619 vrefcnt(vp), dep->de_Name[0]); 620 #endif 621 if (dep->de_Name[0] == SLOT_DELETED) 622 vrecycle(vp, td); 623 return (error); 624 } 625