1 /* $FreeBSD: src/sys/msdosfs/msdosfs_denode.c,v 1.47.2.3 2002/08/22 16:20:15 trhodes Exp $ */
2 /* $DragonFly: src/sys/vfs/msdosfs/msdosfs_denode.c,v 1.10 2004/03/01 06:33:21 dillon Exp $ */
3 /* $NetBSD: msdosfs_denode.c,v 1.28 1998/02/10 14:10:00 mrg Exp $ */
6 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
7 * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
9 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 * 3. All advertising materials mentioning features or use of this software
20 * must display the following acknowledgement:
21 * This product includes software developed by TooLs GmbH.
22 * 4. The name of TooLs GmbH may not be used to endorse or promote products
23 * derived from this software without specific prior written permission.
25 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
29 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
30 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
31 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
32 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
33 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
34 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37 * Written by Paul Popelka (paulp@uts.amdahl.com)
39 * You can do anything you want with this software, just don't say you wrote
40 * it, and don't remove this notice.
42 * This software is provided "as is".
44 * The author supplies this software to be publicly redistributed on the
45 * understanding that the author is not responsible for the correct
46 * functioning of this software in any circumstances and is not liable for
47 * any damages caused by this software.
52 #include <sys/param.h>
53 #include <sys/systm.h>
54 #include <sys/kernel.h>
55 #include <sys/mount.h>
56 #include <sys/malloc.h>
59 #include <sys/vnode.h>
62 #include <vm/vm_extern.h>
65 #include "msdosfsmount.h"
70 static MALLOC_DEFINE(M_MSDOSFSNODE, "MSDOSFS node", "MSDOSFS vnode private part");
72 static struct denode **dehashtbl;
73 static u_long dehash; /* size of hash table - 1 */
74 #define DEHASH(dev, dcl, doff) (dehashtbl[(minor(dev) + (dcl) + (doff) / \
75 sizeof(struct direntry)) & dehash])
76 static struct lwkt_token dehash_token;
82 #define SETHIGH(q, h) { \
85 tmp.val[_QUAD_HIGHWORD] = (h); \
88 #define SETLOW(q, l) { \
91 tmp.val[_QUAD_LOWWORD] = (l); \
95 static struct denode *
96 msdosfs_hashget (dev_t dev, u_long dirclust,
98 static void msdosfs_hashins (struct denode *dep);
99 static void msdosfs_hashrem (struct denode *dep);
104 struct vfsconf *vfsp;
106 dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash);
107 lwkt_token_init(&dehash_token);
113 struct vfsconf *vfsp;
117 free(dehashtbl, M_MSDOSFSMNT);
121 static struct denode *
122 msdosfs_hashget(dev, dirclust, diroff)
127 struct thread *td = curthread; /* XXX */
133 lwkt_gettoken(&ilock, &dehash_token);
135 for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) {
136 if (dirclust != dep->de_dirclust
137 || diroff != dep->de_diroffset
138 || dev != dep->de_dev
139 || dep->de_refcnt == 0) {
143 lwkt_gettoken(&vlock, vp->v_interlock);
145 * We must check to see if the inode has been ripped
146 * out from under us after blocking.
148 for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) {
149 if (dirclust == dep->de_dirclust
150 && diroff == dep->de_diroffset
151 && dev == dep->de_dev
152 && dep->de_refcnt != 0) {
156 if (dep == NULL || DETOV(dep) != vp) {
157 lwkt_reltoken(&vlock);
160 if (vget(vp, &vlock, LK_EXCLUSIVE | LK_INTERLOCK, td))
162 lwkt_reltoken(&ilock);
165 lwkt_reltoken(&ilock);
173 struct denode **depp, *deq;
176 lwkt_gettoken(&ilock, &dehash_token);
177 depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset);
180 deq->de_prev = &dep->de_next;
184 lwkt_reltoken(&ilock);
194 lwkt_gettoken(&ilock, &dehash_token);
197 deq->de_prev = dep->de_prev;
203 lwkt_reltoken(&ilock);
207 * If deget() succeeds it returns with the gotten denode locked().
209 * pmp - address of msdosfsmount structure of the filesystem containing
210 * the denode of interest. The pm_dev field and the address of
211 * the msdosfsmount structure are used.
212 * dirclust - which cluster bp contains, if dirclust is 0 (root directory)
213 * diroffset is relative to the beginning of the root directory,
214 * otherwise it is cluster relative.
215 * diroffset - offset past begin of cluster of denode we want
216 * depp - returns the address of the gotten denode.
219 deget(pmp, dirclust, diroffset, depp)
220 struct msdosfsmount *pmp; /* so we know the maj/min number */
221 u_long dirclust; /* cluster this dir entry came from */
222 u_long diroffset; /* index of entry within the cluster */
223 struct denode **depp; /* returns the addr of the gotten denode */
225 struct thread *td = curthread; /* XXX */
227 dev_t dev = pmp->pm_dev;
228 struct mount *mntp = pmp->pm_mountp;
229 struct direntry *direntptr;
236 printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
237 pmp, dirclust, diroffset, depp);
241 * On FAT32 filesystems, root is a (more or less) normal
244 if (FAT32(pmp) && dirclust == MSDOSFSROOT)
245 dirclust = pmp->pm_rootdirblk;
248 * See if the denode is in the denode cache. Use the location of
249 * the directory entry to compute the hash value. For subdir use
250 * address of "." entry. For root dir (if not FAT32) use cluster
251 * MSDOSFSROOT, offset MSDOSFSROOT_OFS
253 * NOTE: The check for de_refcnt > 0 below insures the denode being
254 * examined does not represent an unlinked but still open file.
255 * These files are not to be accessible even when the directory
256 * entry that represented the file happens to be reused while the
257 * deleted file is still open.
259 ldep = msdosfs_hashget(dev, dirclust, diroffset);
266 * Do the MALLOC before the getnewvnode since doing so afterward
267 * might cause a bogus v_data pointer to get dereferenced
268 * elsewhere if MALLOC should block.
270 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK);
273 * Directory entry was not in cache, have to create a vnode and
274 * copy it from the passed disk buffer.
276 /* getnewvnode() does a VREF() on the vnode */
277 error = getnewvnode(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp);
280 FREE(ldep, M_MSDOSFSNODE);
283 bzero((caddr_t)ldep, sizeof *ldep);
284 lockinit(&ldep->de_lock, 0, "denode", VLKTIMEOUT, 0);
286 ldep->de_vnode = nvp;
290 ldep->de_dirclust = dirclust;
291 ldep->de_diroffset = diroffset;
292 fc_purge(ldep, 0); /* init the fat cache for this denode */
295 * Lock the denode so that it can't be accessed until we've read
296 * it in and have done what we need to it. Do this here instead
297 * of at the start of msdosfs_hashins() so that reinsert() can
298 * call msdosfs_hashins() with a locked denode.
300 if (lockmgr(&ldep->de_lock, LK_EXCLUSIVE, NULL, td))
301 panic("deget: unexpected lock failure");
304 * Insert the denode into the hash queue.
306 msdosfs_hashins(ldep);
311 * Copy the directory entry into the denode area of the vnode.
313 if ((dirclust == MSDOSFSROOT
314 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
315 && diroffset == MSDOSFSROOT_OFS) {
317 * Directory entry for the root directory. There isn't one,
318 * so we manufacture one. We should probably rummage
319 * through the root directory and find a label entry (if it
320 * exists), and then use the time and date from that entry
321 * as the time and date for the root denode.
323 nvp->v_flag |= VROOT; /* should be further down XXX */
325 ldep->de_Attributes = ATTR_DIRECTORY;
326 ldep->de_LowerCase = 0;
328 ldep->de_StartCluster = pmp->pm_rootdirblk;
329 /* de_FileSize will be filled in further down */
331 ldep->de_StartCluster = MSDOSFSROOT;
332 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
335 * fill in time and date so that dos2unixtime() doesn't
336 * spit up when called from msdosfs_getattr() with root
340 ldep->de_CTime = 0x0000; /* 00:00:00 */
341 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
342 | (1 << DD_DAY_SHIFT);
344 ldep->de_ADate = ldep->de_CDate;
345 ldep->de_MTime = ldep->de_CTime;
346 ldep->de_MDate = ldep->de_CDate;
347 /* leave the other fields as garbage */
349 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
352 * The denode does not contain anything useful, so
353 * it would be wrong to leave it on its hash chain.
354 * Arrange for vput() to just forget about it.
356 ldep->de_Name[0] = SLOT_DELETED;
362 DE_INTERNALIZE(ldep, direntptr);
367 * Fill in a few fields of the vnode and finish filling in the
368 * denode. Then return the address of the found denode.
370 if (ldep->de_Attributes & ATTR_DIRECTORY) {
372 * Since DOS directory entries that describe directories
373 * have 0 in the filesize field, we take this opportunity
374 * to find out the length of the directory and plug it into
375 * the denode structure.
380 * XXX Sometimes, these arrives that . entry have cluster
381 * number 0, when it shouldn't. Use real cluster number
382 * instead of what is written in directory entry.
384 if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) {
385 printf("deget(): . entry at clust %ld != %ld\n",
386 dirclust, ldep->de_StartCluster);
387 ldep->de_StartCluster = dirclust;
391 if (ldep->de_StartCluster != MSDOSFSROOT) {
392 error = pcbmap(ldep, 0xffff, 0, &size, 0);
393 if (error == E2BIG) {
394 ldep->de_FileSize = de_cn2off(pmp, size);
397 printf("deget(): pcbmap returned %d\n", error);
402 SETHIGH(ldep->de_modrev, tv.tv_sec);
403 SETLOW(ldep->de_modrev, tv.tv_usec * 4294);
404 ldep->de_devvp = pmp->pm_devvp;
405 VREF(ldep->de_devvp);
411 deupdat(dep, waitfor)
417 struct direntry *dirp;
420 if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY)
423 DETIMES(dep, &ts, &ts, &ts);
424 if ((dep->de_flag & DE_MODIFIED) == 0)
426 dep->de_flag &= ~DE_MODIFIED;
427 if (dep->de_Attributes & ATTR_DIRECTORY)
429 if (dep->de_refcnt <= 0)
431 error = readde(dep, &bp, &dirp);
434 DE_EXTERNALIZE(dirp, dep);
444 * Truncate the file described by dep to the length specified by length.
447 detrunc(dep, length, flags, td)
459 int isadir = dep->de_Attributes & ATTR_DIRECTORY;
461 struct msdosfsmount *pmp = dep->de_pmp;
464 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
468 * Disallow attempts to truncate the root directory since it is of
469 * fixed size. That's just the way dos filesystems are. We use
470 * the VROOT bit in the vnode because checking for the directory
471 * bit and a startcluster of 0 in the denode is not adequate to
472 * recognize the root directory at this point in a file or
475 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp)) {
476 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
477 dep->de_dirclust, dep->de_diroffset);
482 if (dep->de_FileSize < length) {
483 vnode_pager_setsize(DETOV(dep), length);
484 return deextend(dep, length);
488 * If the desired length is 0 then remember the starting cluster of
489 * the file and set the StartCluster field in the directory entry
490 * to 0. If the desired length is not zero, then get the number of
491 * the last cluster in the shortened file. Then get the number of
492 * the first cluster in the part of the file that is to be freed.
493 * Then set the next cluster pointer in the last cluster of the
494 * file to CLUST_EOFE.
497 chaintofree = dep->de_StartCluster;
498 dep->de_StartCluster = 0;
501 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0,
505 printf("detrunc(): pcbmap fails %d\n", error);
511 fc_purge(dep, de_clcount(pmp, length));
514 * If the new length is not a multiple of the cluster size then we
515 * must zero the tail end of the new last cluster in case it
516 * becomes part of the file again because of a seek.
518 if ((boff = length & pmp->pm_crbomask) != 0) {
520 bn = cntobn(pmp, eofentry);
521 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, &bp);
523 bn = de_blk(pmp, length);
524 error = bread(DETOV(dep), bn, pmp->pm_bpcluster, &bp);
529 printf("detrunc(): bread fails %d\n", error);
534 * is this the right place for it?
536 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
544 * Write out the updated directory entry. Even if the update fails
545 * we free the trailing clusters.
547 dep->de_FileSize = length;
549 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
550 allerror = vtruncbuf(DETOV(dep), td, length, pmp->pm_bpcluster);
553 printf("detrunc(): vtruncbuf error %d\n", allerror);
555 error = deupdat(dep, 1);
556 if (error && (allerror == 0))
559 printf("detrunc(): allerror %d, eofentry %lu\n",
564 * If we need to break the cluster chain for the file then do it
567 if (eofentry != ~0) {
568 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
569 &chaintofree, CLUST_EOFE);
572 printf("detrunc(): fatentry errors %d\n", error);
576 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
581 * Now free the clusters removed from the file because of the
584 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
585 freeclusterchain(pmp, chaintofree);
591 * Extend the file described by dep to length specified by length.
594 deextend(dep, length)
598 struct msdosfsmount *pmp = dep->de_pmp;
603 * The root of a DOS filesystem cannot be extended.
605 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp))
609 * Directories cannot be extended.
611 if (dep->de_Attributes & ATTR_DIRECTORY)
614 if (length <= dep->de_FileSize)
615 panic("deextend: file too large");
618 * Compute the number of clusters to allocate.
620 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
622 if (count > pmp->pm_freeclustercount)
624 error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
626 /* truncate the added clusters away again */
627 (void) detrunc(dep, dep->de_FileSize, 0, NULL);
631 dep->de_FileSize = length;
632 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
633 return (deupdat(dep, 1));
637 * Move a denode to its correct hash queue after the file it represents has
638 * been moved to a new directory.
645 * Fix up the denode cache. If the denode is for a directory,
646 * there is nothing to do since the hash is based on the starting
647 * cluster of the directory file and that hasn't changed. If for a
648 * file the hash is based on the location of the directory entry,
649 * so we must remove it from the cache and re-enter it with the
650 * hash based on the new location of the directory entry.
652 if (dep->de_Attributes & ATTR_DIRECTORY)
654 msdosfs_hashrem(dep);
655 msdosfs_hashins(dep);
660 struct vop_reclaim_args /* {
664 struct vnode *vp = ap->a_vp;
665 struct denode *dep = VTODE(vp);
668 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
669 dep, dep->de_Name, dep->de_refcnt);
672 if (prtactive && vp->v_usecount != 0)
673 vprint("msdosfs_reclaim(): pushing active", vp);
675 * Remove the denode from its hash chain.
677 msdosfs_hashrem(dep);
679 * Purge old data structures associated with the denode.
683 vrele(dep->de_devvp);
689 FREE(dep, M_MSDOSFSNODE);
697 struct vop_inactive_args /* {
702 struct vnode *vp = ap->a_vp;
703 struct denode *dep = VTODE(vp);
707 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
710 if (prtactive && vp->v_usecount != 0)
711 vprint("msdosfs_inactive(): pushing active", vp);
714 * Ignore denodes related to stale file handles.
716 if (dep->de_Name[0] == SLOT_DELETED)
720 * If the file has been deleted and it is on a read/write
721 * filesystem, then truncate the file, and mark the directory slot
722 * as empty. (This may not be necessary for the dos filesystem.)
725 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n",
726 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY);
728 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
729 error = detrunc(dep, (u_long) 0, 0, ap->a_td);
730 dep->de_flag |= DE_UPDATE;
731 dep->de_Name[0] = SLOT_DELETED;
736 VOP_UNLOCK(vp, NULL, 0, ap->a_td);
738 * If we are done with the denode, reclaim it
739 * so that it can be reused immediately.
742 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vp->v_usecount,
745 if (dep->de_Name[0] == SLOT_DELETED)
746 vrecycle(vp, NULL, ap->a_td);