2 /* $NetBSD: msdosfs_denode.c,v 1.28 1998/02/10 14:10:00 mrg Exp $ */
5 * SPDX-License-Identifier: BSD-4-Clause
7 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
8 * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
10 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. All advertising materials mentioning features or use of this software
21 * must display the following acknowledgement:
22 * This product includes software developed by TooLs GmbH.
23 * 4. The name of TooLs GmbH may not be used to endorse or promote products
24 * derived from this software without specific prior written permission.
26 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
31 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
32 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
33 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
34 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
35 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 * Written by Paul Popelka (paulp@uts.amdahl.com)
40 * You can do anything you want with this software, just don't say you wrote
41 * it, and don't remove this notice.
43 * This software is provided "as is".
45 * The author supplies this software to be publicly redistributed on the
46 * understanding that the author is not responsible for the correct
47 * functioning of this software in any circumstances and is not liable for
48 * any damages caused by this software.
53 #include <sys/param.h>
54 #include <sys/systm.h>
56 #include <sys/clock.h>
57 #include <sys/kernel.h>
58 #include <sys/malloc.h>
59 #include <sys/mount.h>
60 #include <sys/vmmeter.h>
61 #include <sys/vnode.h>
64 #include <vm/vm_extern.h>
66 #include <fs/msdosfs/bpb.h>
67 #include <fs/msdosfs/direntry.h>
68 #include <fs/msdosfs/denode.h>
69 #include <fs/msdosfs/fat.h>
70 #include <fs/msdosfs/msdosfsmount.h>
72 static MALLOC_DEFINE(M_MSDOSFSNODE, "msdosfs_node", "MSDOSFS vnode private part");
75 de_vncmpf(struct vnode *vp, void *arg)
82 return (de->de_inode != *a);
86 * If deget() succeeds it returns with the gotten denode locked().
88 * pmp - address of msdosfsmount structure of the filesystem containing
89 * the denode of interest. The address of
90 * the msdosfsmount structure are used.
91 * dirclust - which cluster bp contains, if dirclust is 0 (root directory)
92 * diroffset is relative to the beginning of the root directory,
93 * otherwise it is cluster relative.
94 * diroffset - offset past begin of cluster of denode we want
95 * depp - returns the address of the gotten denode.
98 deget(struct msdosfsmount *pmp, u_long dirclust, u_long diroffset,
103 struct mount *mntp = pmp->pm_mountp;
104 struct direntry *direntptr;
106 struct vnode *nvp, *xvp;
110 printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
111 pmp, dirclust, diroffset, depp);
115 * On FAT32 filesystems, root is a (more or less) normal
118 if (FAT32(pmp) && dirclust == MSDOSFSROOT)
119 dirclust = pmp->pm_rootdirblk;
122 * See if the denode is in the denode cache. Use the location of
123 * the directory entry to compute the hash value. For subdir use
124 * address of "." entry. For root dir (if not FAT32) use cluster
125 * MSDOSFSROOT, offset MSDOSFSROOT_OFS
127 * NOTE: The check for de_refcnt > 0 below insures the denode being
128 * examined does not represent an unlinked but still open file.
129 * These files are not to be accessible even when the directory
130 * entry that represented the file happens to be reused while the
131 * deleted file is still open.
133 inode = (uint64_t)pmp->pm_bpcluster * dirclust + diroffset;
135 error = vfs_hash_get(mntp, inode, LK_EXCLUSIVE, curthread, &nvp,
141 KASSERT((*depp)->de_dirclust == dirclust, ("wrong dirclust"));
142 KASSERT((*depp)->de_diroffset == diroffset, ("wrong diroffset"));
145 ldep = malloc(sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK | M_ZERO);
148 * Directory entry was not in cache, have to create a vnode and
149 * copy it from the passed disk buffer.
151 /* getnewvnode() does a VREF() on the vnode */
152 error = getnewvnode("msdosfs", mntp, &msdosfs_vnodeops, &nvp);
155 free(ldep, M_MSDOSFSNODE);
159 ldep->de_vnode = nvp;
161 ldep->de_dirclust = dirclust;
162 ldep->de_diroffset = diroffset;
163 ldep->de_inode = inode;
164 lockmgr(nvp->v_vnlock, LK_EXCLUSIVE, NULL);
165 fc_purge(ldep, 0); /* init the FAT cache for this denode */
166 error = insmntque(nvp, mntp);
168 free(ldep, M_MSDOSFSNODE);
172 error = vfs_hash_insert(nvp, inode, LK_EXCLUSIVE, curthread, &xvp,
186 * Copy the directory entry into the denode area of the vnode.
188 if ((dirclust == MSDOSFSROOT
189 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
190 && diroffset == MSDOSFSROOT_OFS) {
192 * Directory entry for the root directory. There isn't one,
193 * so we manufacture one. We should probably rummage
194 * through the root directory and find a label entry (if it
195 * exists), and then use the time and date from that entry
196 * as the time and date for the root denode.
198 nvp->v_vflag |= VV_ROOT; /* should be further down XXX */
200 ldep->de_Attributes = ATTR_DIRECTORY;
201 ldep->de_LowerCase = 0;
203 ldep->de_StartCluster = pmp->pm_rootdirblk;
204 /* de_FileSize will be filled in further down */
206 ldep->de_StartCluster = MSDOSFSROOT;
207 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
210 * fill in time and date so that fattime2timespec() doesn't
211 * spit up when called from msdosfs_getattr() with root
215 ldep->de_CTime = 0x0000; /* 00:00:00 */
216 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
217 | (1 << DD_DAY_SHIFT);
219 ldep->de_ADate = ldep->de_CDate;
220 ldep->de_MTime = ldep->de_CTime;
221 ldep->de_MDate = ldep->de_CDate;
222 /* leave the other fields as garbage */
224 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
227 * The denode does not contain anything useful, so
228 * it would be wrong to leave it on its hash chain.
229 * Arrange for vput() to just forget about it.
231 ldep->de_Name[0] = SLOT_DELETED;
237 (void)DE_INTERNALIZE(ldep, direntptr);
242 * Fill in a few fields of the vnode and finish filling in the
243 * denode. Then return the address of the found denode.
245 if (ldep->de_Attributes & ATTR_DIRECTORY) {
247 * Since DOS directory entries that describe directories
248 * have 0 in the filesize field, we take this opportunity
249 * to find out the length of the directory and plug it into
250 * the denode structure.
255 * XXX it sometimes happens that the "." entry has cluster
256 * number 0 when it shouldn't. Use the actual cluster number
257 * instead of what is written in directory entry.
259 if (diroffset == 0 && ldep->de_StartCluster != dirclust) {
261 printf("deget(): \".\" entry at clust %lu != %lu\n",
262 dirclust, ldep->de_StartCluster);
264 ldep->de_StartCluster = dirclust;
268 if (ldep->de_StartCluster != MSDOSFSROOT) {
269 error = pcbmap(ldep, 0xffff, 0, &size, 0);
270 if (error == E2BIG) {
271 ldep->de_FileSize = de_cn2off(pmp, size);
275 printf("deget(): pcbmap returned %d\n", error);
281 ldep->de_modrev = init_va_filerev();
287 deupdat(struct denode *dep, int waitfor)
292 struct direntry *dirp;
295 if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY) {
296 dep->de_flag &= ~(DE_UPDATE | DE_CREATE | DE_ACCESS |
301 DETIMES(dep, &ts, &ts, &ts);
302 if ((dep->de_flag & DE_MODIFIED) == 0 && waitfor == 0)
304 dep->de_flag &= ~DE_MODIFIED;
305 if (DETOV(dep)->v_vflag & VV_ROOT)
307 if (dep->de_refcnt <= 0)
309 error = readde(dep, &bp, &dirp);
312 DE_EXTERNALIZE(&dir, dep);
313 if (bcmp(dirp, &dir, sizeof(dir)) == 0) {
314 if (waitfor == 0 || (bp->b_flags & B_DELWRI) == 0) {
320 if ((DETOV(dep)->v_mount->mnt_flag & MNT_NOCLUSTERW) == 0)
321 bp->b_flags |= B_CLUSTEROK;
324 else if (vm_page_count_severe() || buf_dirty_count_severe())
332 * Truncate the file described by dep to the length specified by length.
335 detrunc(struct denode *dep, u_long length, int flags, struct ucred *cred)
343 int isadir = dep->de_Attributes & ATTR_DIRECTORY;
345 struct msdosfsmount *pmp = dep->de_pmp;
348 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
352 * Disallow attempts to truncate the root directory since it is of
353 * fixed size. That's just the way dos filesystems are. We use
354 * the VROOT bit in the vnode because checking for the directory
355 * bit and a startcluster of 0 in the denode is not adequate to
356 * recognize the root directory at this point in a file or
359 if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) {
361 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
362 dep->de_dirclust, dep->de_diroffset);
367 if (dep->de_FileSize < length) {
368 vnode_pager_setsize(DETOV(dep), length);
369 return deextend(dep, length, cred);
373 * If the desired length is 0 then remember the starting cluster of
374 * the file and set the StartCluster field in the directory entry
375 * to 0. If the desired length is not zero, then get the number of
376 * the last cluster in the shortened file. Then get the number of
377 * the first cluster in the part of the file that is to be freed.
378 * Then set the next cluster pointer in the last cluster of the
379 * file to CLUST_EOFE.
382 chaintofree = dep->de_StartCluster;
383 dep->de_StartCluster = 0;
386 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0,
390 printf("detrunc(): pcbmap fails %d\n", error);
396 fc_purge(dep, de_clcount(pmp, length));
399 * If the new length is not a multiple of the cluster size then we
400 * must zero the tail end of the new last cluster in case it
401 * becomes part of the file again because of a seek.
403 if ((boff = length & pmp->pm_crbomask) != 0) {
405 bn = cntobn(pmp, eofentry);
406 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
411 printf("detrunc(): bread fails %d\n", error);
415 memset(bp->b_data + boff, 0, pmp->pm_bpcluster - boff);
424 * Write out the updated directory entry. Even if the update fails
425 * we free the trailing clusters.
427 dep->de_FileSize = length;
429 dep->de_flag |= DE_UPDATE | DE_MODIFIED;
430 allerror = vtruncbuf(DETOV(dep), cred, length, pmp->pm_bpcluster);
433 printf("detrunc(): vtruncbuf error %d\n", allerror);
435 error = deupdat(dep, !DOINGASYNC((DETOV(dep))));
436 if (error != 0 && allerror == 0)
439 printf("detrunc(): allerror %d, eofentry %lu\n",
444 * If we need to break the cluster chain for the file then do it
447 if (eofentry != ~0) {
448 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
449 &chaintofree, CLUST_EOFE);
452 printf("detrunc(): fatentry errors %d\n", error);
456 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
461 * Now free the clusters removed from the file because of the
464 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
465 freeclusterchain(pmp, chaintofree);
471 * Extend the file described by dep to length specified by length.
474 deextend(struct denode *dep, u_long length, struct ucred *cred)
476 struct msdosfsmount *pmp = dep->de_pmp;
481 * The root of a DOS filesystem cannot be extended.
483 if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp))
487 * Directories cannot be extended.
489 if (dep->de_Attributes & ATTR_DIRECTORY)
492 if (length <= dep->de_FileSize)
493 panic("deextend: file too large");
496 * Compute the number of clusters to allocate.
498 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
500 if (count > pmp->pm_freeclustercount)
502 error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
504 /* truncate the added clusters away again */
505 (void) detrunc(dep, dep->de_FileSize, 0, cred);
509 dep->de_FileSize = length;
510 dep->de_flag |= DE_UPDATE | DE_MODIFIED;
511 return (deupdat(dep, !DOINGASYNC(DETOV(dep))));
515 * Move a denode to its correct hash queue after the file it represents has
516 * been moved to a new directory.
519 reinsert(struct denode *dep)
524 * Fix up the denode cache. If the denode is for a directory,
525 * there is nothing to do since the hash is based on the starting
526 * cluster of the directory file and that hasn't changed. If for a
527 * file the hash is based on the location of the directory entry,
528 * so we must remove it from the cache and re-enter it with the
529 * hash based on the new location of the directory entry.
532 if (dep->de_Attributes & ATTR_DIRECTORY)
536 dep->de_inode = (uint64_t)dep->de_pmp->pm_bpcluster * dep->de_dirclust +
538 vfs_hash_rehash(vp, dep->de_inode);
542 msdosfs_reclaim(struct vop_reclaim_args *ap)
544 struct vnode *vp = ap->a_vp;
545 struct denode *dep = VTODE(vp);
548 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
549 dep, dep->de_Name, dep->de_refcnt);
553 * Destroy the vm object and flush associated pages.
555 vnode_destroy_vobject(vp);
557 * Remove the denode from its hash chain.
561 * Purge old data structures associated with the denode.
566 free(dep, M_MSDOSFSNODE);
573 msdosfs_inactive(struct vop_inactive_args *ap)
575 struct vnode *vp = ap->a_vp;
576 struct denode *dep = VTODE(vp);
580 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
584 * Ignore denodes related to stale file handles.
586 if (dep->de_Name[0] == SLOT_DELETED || dep->de_Name[0] == SLOT_EMPTY)
590 * If the file has been deleted and it is on a read/write
591 * filesystem, then truncate the file, and mark the directory slot
592 * as empty. (This may not be necessary for the dos filesystem.)
595 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %llx, MNT_RDONLY %llx\n",
596 dep, dep->de_refcnt, (unsigned long long)vp->v_mount->mnt_flag,
597 (unsigned long long)MNT_RDONLY);
599 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
600 error = detrunc(dep, (u_long) 0, 0, NOCRED);
601 dep->de_flag |= DE_UPDATE;
602 dep->de_Name[0] = SLOT_DELETED;
608 * If we are done with the denode, reclaim it
609 * so that it can be reused immediately.
612 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n",
613 vrefcnt(vp), dep->de_Name[0]);
615 if (dep->de_Name[0] == SLOT_DELETED || dep->de_Name[0] == SLOT_EMPTY)