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/buf.h>
54 #include <sys/clock.h>
55 #include <sys/kernel.h>
56 #include <sys/malloc.h>
57 #include <sys/mount.h>
58 #include <sys/vnode.h>
59
60 #include <vm/vm.h>
61 #include <vm/vm_extern.h>
62
63 #include <fs/msdosfs/bpb.h>
64 #include <fs/msdosfs/direntry.h>
65 #include <fs/msdosfs/denode.h>
66 #include <fs/msdosfs/fat.h>
67 #include <fs/msdosfs/msdosfsmount.h>
68
69 static MALLOC_DEFINE(M_MSDOSFSNODE, "msdosfs_node", "MSDOSFS vnode private part");
70
71 static int
72 de_vncmpf(struct vnode *vp, void *arg)
73 {
74 struct denode *de;
75 uint64_t *a;
76
77 a = arg;
78 de = VTODE(vp);
79 return (de->de_inode != *a);
80 }
81
82 /*
83 * If deget() succeeds it returns with the gotten denode locked().
84 *
85 * pmp - address of msdosfsmount structure of the filesystem containing
86 * the denode of interest. The address of
87 * the msdosfsmount structure are used.
88 * dirclust - which cluster bp contains, if dirclust is 0 (root directory)
89 * diroffset is relative to the beginning of the root directory,
90 * otherwise it is cluster relative.
91 * diroffset - offset past begin of cluster of denode we want
92 * depp - returns the address of the gotten denode.
93 */
94 int
95 deget(pmp, dirclust, diroffset, depp)
96 struct msdosfsmount *pmp; /* so we know the maj/min number */
97 u_long dirclust; /* cluster this dir entry came from */
98 u_long diroffset; /* index of entry within the cluster */
99 struct denode **depp; /* returns the addr of the gotten denode */
100 {
101 int error;
102 uint64_t inode;
103 struct mount *mntp = pmp->pm_mountp;
104 struct direntry *direntptr;
105 struct denode *ldep;
106 struct vnode *nvp, *xvp;
107 struct buf *bp;
108 struct thread *td;
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 td = curthread;
175 lockmgr(nvp->v_vnlock, LK_EXCLUSIVE, NULL, td);
176 error = insmntque(nvp, mntp);
177 if (error != 0) {
178 FREE(ldep, M_MSDOSFSNODE);
179 *depp = NULL;
180 return (error);
181 }
182 error = vfs_hash_insert(nvp, inode, LK_EXCLUSIVE, td, &xvp,
183 de_vncmpf, &inode);
184 if (error) {
185 *depp = NULL;
186 return (error);
187 }
188 if (xvp != NULL) {
189 /* XXX: Not sure this is right */
190 nvp = xvp;
191 ldep->de_vnode = nvp;
192 }
193
194 ldep->de_pmp = pmp;
195 ldep->de_refcnt = 1;
196 /*
197 * Copy the directory entry into the denode area of the vnode.
198 */
199 if ((dirclust == MSDOSFSROOT
200 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
201 && diroffset == MSDOSFSROOT_OFS) {
202 /*
203 * Directory entry for the root directory. There isn't one,
204 * so we manufacture one. We should probably rummage
205 * through the root directory and find a label entry (if it
206 * exists), and then use the time and date from that entry
207 * as the time and date for the root denode.
208 */
209 nvp->v_vflag |= VV_ROOT; /* should be further down XXX */
210
211 ldep->de_Attributes = ATTR_DIRECTORY;
212 ldep->de_LowerCase = 0;
213 if (FAT32(pmp))
214 ldep->de_StartCluster = pmp->pm_rootdirblk;
215 /* de_FileSize will be filled in further down */
216 else {
217 ldep->de_StartCluster = MSDOSFSROOT;
218 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
219 }
220 /*
221 * fill in time and date so that fattime2timespec() doesn't
222 * spit up when called from msdosfs_getattr() with root
223 * denode
224 */
225 ldep->de_CHun = 0;
226 ldep->de_CTime = 0x0000; /* 00:00:00 */
227 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
228 | (1 << DD_DAY_SHIFT);
229 /* Jan 1, 1980 */
230 ldep->de_ADate = ldep->de_CDate;
231 ldep->de_MTime = ldep->de_CTime;
232 ldep->de_MDate = ldep->de_CDate;
233 /* leave the other fields as garbage */
234 } else {
235 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
236 if (error) {
237 /*
238 * The denode does not contain anything useful, so
239 * it would be wrong to leave it on its hash chain.
240 * Arrange for vput() to just forget about it.
241 */
242 ldep->de_Name[0] = SLOT_DELETED;
243
244 vput(nvp);
245 *depp = NULL;
246 return (error);
247 }
248 DE_INTERNALIZE(ldep, direntptr);
249 brelse(bp);
250 }
251
252 /*
253 * Fill in a few fields of the vnode and finish filling in the
254 * denode. Then return the address of the found denode.
255 */
256 if (ldep->de_Attributes & ATTR_DIRECTORY) {
257 /*
258 * Since DOS directory entries that describe directories
259 * have 0 in the filesize field, we take this opportunity
260 * to find out the length of the directory and plug it into
261 * the denode structure.
262 */
263 u_long size;
264
265 /*
266 * XXX it sometimes happens that the "." entry has cluster
267 * number 0 when it shouldn't. Use the actual cluster number
268 * instead of what is written in directory entry.
269 */
270 if (diroffset == 0 && ldep->de_StartCluster != dirclust) {
271 printf("deget(): \".\" entry at clust %lu != %lu\n",
272 dirclust, ldep->de_StartCluster);
273 ldep->de_StartCluster = dirclust;
274 }
275
276 nvp->v_type = VDIR;
277 if (ldep->de_StartCluster != MSDOSFSROOT) {
278 error = pcbmap(ldep, 0xffff, 0, &size, 0);
279 if (error == E2BIG) {
280 ldep->de_FileSize = de_cn2off(pmp, size);
281 error = 0;
282 } else
283 printf("deget(): pcbmap returned %d\n", error);
284 }
285 } else
286 nvp->v_type = VREG;
287 ldep->de_modrev = init_va_filerev();
288 *depp = ldep;
289 return (0);
290 }
291
292 int
293 deupdat(dep, waitfor)
294 struct denode *dep;
295 int waitfor;
296 {
297 int error;
298 struct buf *bp;
299 struct direntry *dirp;
300 struct timespec ts;
301
302 if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY)
303 return (0);
304 getnanotime(&ts);
305 DETIMES(dep, &ts, &ts, &ts);
306 if ((dep->de_flag & DE_MODIFIED) == 0)
307 return (0);
308 dep->de_flag &= ~DE_MODIFIED;
309 if (dep->de_Attributes & ATTR_DIRECTORY)
310 return (0);
311 if (dep->de_refcnt <= 0)
312 return (0);
313 error = readde(dep, &bp, &dirp);
314 if (error)
315 return (error);
316 DE_EXTERNALIZE(dirp, dep);
317 if (waitfor)
318 return (bwrite(bp));
319 else {
320 bdwrite(bp);
321 return (0);
322 }
323 }
324
325 /*
326 * Truncate the file described by dep to the length specified by length.
327 */
328 int
329 detrunc(dep, length, flags, cred, td)
330 struct denode *dep;
331 u_long length;
332 int flags;
333 struct ucred *cred;
334 struct thread *td;
335 {
336 int error;
337 int allerror;
338 u_long eofentry;
339 u_long chaintofree;
340 daddr_t bn;
341 int boff;
342 int isadir = dep->de_Attributes & ATTR_DIRECTORY;
343 struct buf *bp;
344 struct msdosfsmount *pmp = dep->de_pmp;
345
346 #ifdef MSDOSFS_DEBUG
347 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
348 #endif
349
350 /*
351 * Disallow attempts to truncate the root directory since it is of
352 * fixed size. That's just the way dos filesystems are. We use
353 * the VROOT bit in the vnode because checking for the directory
354 * bit and a startcluster of 0 in the denode is not adequate to
355 * recognize the root directory at this point in a file or
356 * directory's life.
357 */
358 if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) {
359 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
360 dep->de_dirclust, dep->de_diroffset);
361 return (EINVAL);
362 }
363
364 if (dep->de_FileSize < length) {
365 vnode_pager_setsize(DETOV(dep), length);
366 return deextend(dep, length, cred);
367 }
368
369 /*
370 * If the desired length is 0 then remember the starting cluster of
371 * the file and set the StartCluster field in the directory entry
372 * to 0. If the desired length is not zero, then get the number of
373 * the last cluster in the shortened file. Then get the number of
374 * the first cluster in the part of the file that is to be freed.
375 * Then set the next cluster pointer in the last cluster of the
376 * file to CLUST_EOFE.
377 */
378 if (length == 0) {
379 chaintofree = dep->de_StartCluster;
380 dep->de_StartCluster = 0;
381 eofentry = ~0;
382 } else {
383 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0,
384 &eofentry, 0);
385 if (error) {
386 #ifdef MSDOSFS_DEBUG
387 printf("detrunc(): pcbmap fails %d\n", error);
388 #endif
389 return (error);
390 }
391 }
392
393 fc_purge(dep, de_clcount(pmp, length));
394
395 /*
396 * If the new length is not a multiple of the cluster size then we
397 * must zero the tail end of the new last cluster in case it
398 * becomes part of the file again because of a seek.
399 */
400 if ((boff = length & pmp->pm_crbomask) != 0) {
401 if (isadir) {
402 bn = cntobn(pmp, eofentry);
403 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
404 NOCRED, &bp);
405 if (error) {
406 brelse(bp);
407 #ifdef MSDOSFS_DEBUG
408 printf("detrunc(): bread fails %d\n", error);
409 #endif
410 return (error);
411 }
412 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
413 if (flags & IO_SYNC)
414 bwrite(bp);
415 else
416 bdwrite(bp);
417 }
418 }
419
420 /*
421 * Write out the updated directory entry. Even if the update fails
422 * we free the trailing clusters.
423 */
424 dep->de_FileSize = length;
425 if (!isadir)
426 dep->de_flag |= DE_UPDATE | DE_MODIFIED;
427 allerror = vtruncbuf(DETOV(dep), cred, td, length, pmp->pm_bpcluster);
428 #ifdef MSDOSFS_DEBUG
429 if (allerror)
430 printf("detrunc(): vtruncbuf error %d\n", allerror);
431 #endif
432 error = deupdat(dep, 1);
433 if (error != 0 && allerror == 0)
434 allerror = error;
435 #ifdef MSDOSFS_DEBUG
436 printf("detrunc(): allerror %d, eofentry %lu\n",
437 allerror, eofentry);
438 #endif
439
440 /*
441 * If we need to break the cluster chain for the file then do it
442 * now.
443 */
444 if (eofentry != ~0) {
445 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
446 &chaintofree, CLUST_EOFE);
447 if (error) {
448 #ifdef MSDOSFS_DEBUG
449 printf("detrunc(): fatentry errors %d\n", error);
450 #endif
451 return (error);
452 }
453 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
454 eofentry);
455 }
456
457 /*
458 * Now free the clusters removed from the file because of the
459 * truncation.
460 */
461 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
462 freeclusterchain(pmp, chaintofree);
463
464 return (allerror);
465 }
466
467 /*
468 * Extend the file described by dep to length specified by length.
469 */
470 int
471 deextend(dep, length, cred)
472 struct denode *dep;
473 u_long length;
474 struct ucred *cred;
475 {
476 struct msdosfsmount *pmp = dep->de_pmp;
477 u_long count;
478 int error;
479
480 /*
481 * The root of a DOS filesystem cannot be extended.
482 */
483 if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp))
484 return (EINVAL);
485
486 /*
487 * Directories cannot be extended.
488 */
489 if (dep->de_Attributes & ATTR_DIRECTORY)
490 return (EISDIR);
491
492 if (length <= dep->de_FileSize)
493 panic("deextend: file too large");
494
495 /*
496 * Compute the number of clusters to allocate.
497 */
498 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
499 if (count > 0) {
500 if (count > pmp->pm_freeclustercount)
501 return (ENOSPC);
502 error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
503 if (error) {
504 /* truncate the added clusters away again */
505 (void) detrunc(dep, dep->de_FileSize, 0, cred, NULL);
506 return (error);
507 }
508 }
509 dep->de_FileSize = length;
510 dep->de_flag |= DE_UPDATE | DE_MODIFIED;
511 return (deupdat(dep, 1));
512 }
513
514 /*
515 * Move a denode to its correct hash queue after the file it represents has
516 * been moved to a new directory.
517 */
518 void
519 reinsert(dep)
520 struct denode *dep;
521 {
522 struct vnode *vp;
523
524 /*
525 * Fix up the denode cache. If the denode is for a directory,
526 * there is nothing to do since the hash is based on the starting
527 * cluster of the directory file and that hasn't changed. If for a
528 * file the hash is based on the location of the directory entry,
529 * so we must remove it from the cache and re-enter it with the
530 * hash based on the new location of the directory entry.
531 */
532 #if 0
533 if (dep->de_Attributes & ATTR_DIRECTORY)
534 return;
535 #endif
536 vp = DETOV(dep);
537 dep->de_inode = (uint64_t)dep->de_pmp->pm_bpcluster * dep->de_dirclust +
538 dep->de_diroffset;
539 vfs_hash_rehash(vp, dep->de_inode);
540 }
541
542 int
543 msdosfs_reclaim(ap)
544 struct vop_reclaim_args /* {
545 struct vnode *a_vp;
546 } */ *ap;
547 {
548 struct vnode *vp = ap->a_vp;
549 struct denode *dep = VTODE(vp);
550
551 #ifdef MSDOSFS_DEBUG
552 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
553 dep, dep->de_Name, dep->de_refcnt);
554 #endif
555
556 if (prtactive && vrefcnt(vp) != 0)
557 vprint("msdosfs_reclaim(): pushing active", vp);
558 /*
559 * Destroy the vm object and flush associated pages.
560 */
561 vnode_destroy_vobject(vp);
562 /*
563 * Remove the denode from its hash chain.
564 */
565 vfs_hash_remove(vp);
566 /*
567 * Purge old data structures associated with the denode.
568 */
569 #if 0 /* XXX */
570 dep->de_flag = 0;
571 #endif
572 FREE(dep, M_MSDOSFSNODE);
573 vp->v_data = NULL;
574
575 return (0);
576 }
577
578 int
579 msdosfs_inactive(ap)
580 struct vop_inactive_args /* {
581 struct vnode *a_vp;
582 struct thread *a_td;
583 } */ *ap;
584 {
585 struct vnode *vp = ap->a_vp;
586 struct denode *dep = VTODE(vp);
587 struct thread *td = ap->a_td;
588 int error = 0;
589
590 #ifdef MSDOSFS_DEBUG
591 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
592 #endif
593
594 if (prtactive && vrefcnt(vp) != 0)
595 vprint("msdosfs_inactive(): pushing active", vp);
596
597 /*
598 * Ignore denodes related to stale file handles.
599 */
600 if (dep->de_Name[0] == SLOT_DELETED)
601 goto out;
602
603 /*
604 * If the file has been deleted and it is on a read/write
605 * filesystem, then truncate the file, and mark the directory slot
606 * as empty. (This may not be necessary for the dos filesystem.)
607 */
608 #ifdef MSDOSFS_DEBUG
609 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n",
610 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY);
611 #endif
612 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
613 error = detrunc(dep, (u_long) 0, 0, NOCRED, td);
614 dep->de_flag |= DE_UPDATE;
615 dep->de_Name[0] = SLOT_DELETED;
616 }
617 deupdat(dep, 0);
618
619 out:
620 /*
621 * If we are done with the denode, reclaim it
622 * so that it can be reused immediately.
623 */
624 #ifdef MSDOSFS_DEBUG
625 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n",
626 vrefcnt(vp), dep->de_Name[0]);
627 #endif
628 if (dep->de_Name[0] == SLOT_DELETED)
629 vrecycle(vp, td);
630 return (error);
631 }
Cache object: 8e49820cbfd1af9903124ef0e2663ff2
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