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 1.9 2003/10/18 20:15:08 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_inittoken(&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 */
132 gen = lwkt_gettoken(&dehash_token);
134 for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) {
135 if (dirclust == dep->de_dirclust
136 && diroff == dep->de_diroffset
137 && dev == dep->de_dev
138 && dep->de_refcnt != 0) {
140 lwkt_gettoken(&vp->v_interlock);
141 if (lwkt_gentoken(&dehash_token, &gen) != 0) {
142 lwkt_reltoken(&vp->v_interlock);
145 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td)) {
146 lwkt_gentoken(&dehash_token, &gen);
149 if (lwkt_reltoken(&dehash_token) != gen) {
151 gen = lwkt_gettoken(&dehash_token);
157 lwkt_reltoken(&dehash_token);
165 struct denode **depp, *deq;
167 lwkt_gettoken(&dehash_token);
168 depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset);
171 deq->de_prev = &dep->de_next;
175 lwkt_reltoken(&dehash_token);
184 lwkt_gettoken(&dehash_token);
187 deq->de_prev = dep->de_prev;
193 lwkt_reltoken(&dehash_token);
197 * If deget() succeeds it returns with the gotten denode locked().
199 * pmp - address of msdosfsmount structure of the filesystem containing
200 * the denode of interest. The pm_dev field and the address of
201 * the msdosfsmount structure are used.
202 * dirclust - which cluster bp contains, if dirclust is 0 (root directory)
203 * diroffset is relative to the beginning of the root directory,
204 * otherwise it is cluster relative.
205 * diroffset - offset past begin of cluster of denode we want
206 * depp - returns the address of the gotten denode.
209 deget(pmp, dirclust, diroffset, depp)
210 struct msdosfsmount *pmp; /* so we know the maj/min number */
211 u_long dirclust; /* cluster this dir entry came from */
212 u_long diroffset; /* index of entry within the cluster */
213 struct denode **depp; /* returns the addr of the gotten denode */
215 struct thread *td = curthread; /* XXX */
217 dev_t dev = pmp->pm_dev;
218 struct mount *mntp = pmp->pm_mountp;
219 struct direntry *direntptr;
226 printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
227 pmp, dirclust, diroffset, depp);
231 * On FAT32 filesystems, root is a (more or less) normal
234 if (FAT32(pmp) && dirclust == MSDOSFSROOT)
235 dirclust = pmp->pm_rootdirblk;
238 * See if the denode is in the denode cache. Use the location of
239 * the directory entry to compute the hash value. For subdir use
240 * address of "." entry. For root dir (if not FAT32) use cluster
241 * MSDOSFSROOT, offset MSDOSFSROOT_OFS
243 * NOTE: The check for de_refcnt > 0 below insures the denode being
244 * examined does not represent an unlinked but still open file.
245 * These files are not to be accessible even when the directory
246 * entry that represented the file happens to be reused while the
247 * deleted file is still open.
249 ldep = msdosfs_hashget(dev, dirclust, diroffset);
256 * Do the MALLOC before the getnewvnode since doing so afterward
257 * might cause a bogus v_data pointer to get dereferenced
258 * elsewhere if MALLOC should block.
260 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK);
263 * Directory entry was not in cache, have to create a vnode and
264 * copy it from the passed disk buffer.
266 /* getnewvnode() does a VREF() on the vnode */
267 error = getnewvnode(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp);
270 FREE(ldep, M_MSDOSFSNODE);
273 bzero((caddr_t)ldep, sizeof *ldep);
274 lockinit(&ldep->de_lock, 0, "denode", VLKTIMEOUT, 0);
276 ldep->de_vnode = nvp;
280 ldep->de_dirclust = dirclust;
281 ldep->de_diroffset = diroffset;
282 fc_purge(ldep, 0); /* init the fat cache for this denode */
285 * Lock the denode so that it can't be accessed until we've read
286 * it in and have done what we need to it. Do this here instead
287 * of at the start of msdosfs_hashins() so that reinsert() can
288 * call msdosfs_hashins() with a locked denode.
290 if (lockmgr(&ldep->de_lock, LK_EXCLUSIVE, NULL, td))
291 panic("deget: unexpected lock failure");
294 * Insert the denode into the hash queue.
296 msdosfs_hashins(ldep);
301 * Copy the directory entry into the denode area of the vnode.
303 if ((dirclust == MSDOSFSROOT
304 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
305 && diroffset == MSDOSFSROOT_OFS) {
307 * Directory entry for the root directory. There isn't one,
308 * so we manufacture one. We should probably rummage
309 * through the root directory and find a label entry (if it
310 * exists), and then use the time and date from that entry
311 * as the time and date for the root denode.
313 nvp->v_flag |= VROOT; /* should be further down XXX */
315 ldep->de_Attributes = ATTR_DIRECTORY;
316 ldep->de_LowerCase = 0;
318 ldep->de_StartCluster = pmp->pm_rootdirblk;
319 /* de_FileSize will be filled in further down */
321 ldep->de_StartCluster = MSDOSFSROOT;
322 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
325 * fill in time and date so that dos2unixtime() doesn't
326 * spit up when called from msdosfs_getattr() with root
330 ldep->de_CTime = 0x0000; /* 00:00:00 */
331 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
332 | (1 << DD_DAY_SHIFT);
334 ldep->de_ADate = ldep->de_CDate;
335 ldep->de_MTime = ldep->de_CTime;
336 ldep->de_MDate = ldep->de_CDate;
337 /* leave the other fields as garbage */
339 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
342 * The denode does not contain anything useful, so
343 * it would be wrong to leave it on its hash chain.
344 * Arrange for vput() to just forget about it.
346 ldep->de_Name[0] = SLOT_DELETED;
352 DE_INTERNALIZE(ldep, direntptr);
357 * Fill in a few fields of the vnode and finish filling in the
358 * denode. Then return the address of the found denode.
360 if (ldep->de_Attributes & ATTR_DIRECTORY) {
362 * Since DOS directory entries that describe directories
363 * have 0 in the filesize field, we take this opportunity
364 * to find out the length of the directory and plug it into
365 * the denode structure.
370 * XXX Sometimes, these arrives that . entry have cluster
371 * number 0, when it shouldn't. Use real cluster number
372 * instead of what is written in directory entry.
374 if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) {
375 printf("deget(): . entry at clust %ld != %ld\n",
376 dirclust, ldep->de_StartCluster);
377 ldep->de_StartCluster = dirclust;
381 if (ldep->de_StartCluster != MSDOSFSROOT) {
382 error = pcbmap(ldep, 0xffff, 0, &size, 0);
383 if (error == E2BIG) {
384 ldep->de_FileSize = de_cn2off(pmp, size);
387 printf("deget(): pcbmap returned %d\n", error);
392 SETHIGH(ldep->de_modrev, tv.tv_sec);
393 SETLOW(ldep->de_modrev, tv.tv_usec * 4294);
394 ldep->de_devvp = pmp->pm_devvp;
395 VREF(ldep->de_devvp);
401 deupdat(dep, waitfor)
407 struct direntry *dirp;
410 if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY)
413 DETIMES(dep, &ts, &ts, &ts);
414 if ((dep->de_flag & DE_MODIFIED) == 0)
416 dep->de_flag &= ~DE_MODIFIED;
417 if (dep->de_Attributes & ATTR_DIRECTORY)
419 if (dep->de_refcnt <= 0)
421 error = readde(dep, &bp, &dirp);
424 DE_EXTERNALIZE(dirp, dep);
434 * Truncate the file described by dep to the length specified by length.
437 detrunc(dep, length, flags, td)
449 int isadir = dep->de_Attributes & ATTR_DIRECTORY;
451 struct msdosfsmount *pmp = dep->de_pmp;
454 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
458 * Disallow attempts to truncate the root directory since it is of
459 * fixed size. That's just the way dos filesystems are. We use
460 * the VROOT bit in the vnode because checking for the directory
461 * bit and a startcluster of 0 in the denode is not adequate to
462 * recognize the root directory at this point in a file or
465 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp)) {
466 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
467 dep->de_dirclust, dep->de_diroffset);
472 if (dep->de_FileSize < length) {
473 vnode_pager_setsize(DETOV(dep), length);
474 return deextend(dep, length);
478 * If the desired length is 0 then remember the starting cluster of
479 * the file and set the StartCluster field in the directory entry
480 * to 0. If the desired length is not zero, then get the number of
481 * the last cluster in the shortened file. Then get the number of
482 * the first cluster in the part of the file that is to be freed.
483 * Then set the next cluster pointer in the last cluster of the
484 * file to CLUST_EOFE.
487 chaintofree = dep->de_StartCluster;
488 dep->de_StartCluster = 0;
491 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0,
495 printf("detrunc(): pcbmap fails %d\n", error);
501 fc_purge(dep, de_clcount(pmp, length));
504 * If the new length is not a multiple of the cluster size then we
505 * must zero the tail end of the new last cluster in case it
506 * becomes part of the file again because of a seek.
508 if ((boff = length & pmp->pm_crbomask) != 0) {
510 bn = cntobn(pmp, eofentry);
511 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, &bp);
513 bn = de_blk(pmp, length);
514 error = bread(DETOV(dep), bn, pmp->pm_bpcluster, &bp);
519 printf("detrunc(): bread fails %d\n", error);
524 * is this the right place for it?
526 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
534 * Write out the updated directory entry. Even if the update fails
535 * we free the trailing clusters.
537 dep->de_FileSize = length;
539 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
540 allerror = vtruncbuf(DETOV(dep), td, length, pmp->pm_bpcluster);
543 printf("detrunc(): vtruncbuf error %d\n", allerror);
545 error = deupdat(dep, 1);
546 if (error && (allerror == 0))
549 printf("detrunc(): allerror %d, eofentry %lu\n",
554 * If we need to break the cluster chain for the file then do it
557 if (eofentry != ~0) {
558 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
559 &chaintofree, CLUST_EOFE);
562 printf("detrunc(): fatentry errors %d\n", error);
566 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
571 * Now free the clusters removed from the file because of the
574 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
575 freeclusterchain(pmp, chaintofree);
581 * Extend the file described by dep to length specified by length.
584 deextend(dep, length)
588 struct msdosfsmount *pmp = dep->de_pmp;
593 * The root of a DOS filesystem cannot be extended.
595 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp))
599 * Directories cannot be extended.
601 if (dep->de_Attributes & ATTR_DIRECTORY)
604 if (length <= dep->de_FileSize)
605 panic("deextend: file too large");
608 * Compute the number of clusters to allocate.
610 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
612 if (count > pmp->pm_freeclustercount)
614 error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
616 /* truncate the added clusters away again */
617 (void) detrunc(dep, dep->de_FileSize, 0, NULL);
621 dep->de_FileSize = length;
622 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
623 return (deupdat(dep, 1));
627 * Move a denode to its correct hash queue after the file it represents has
628 * been moved to a new directory.
635 * Fix up the denode cache. If the denode is for a directory,
636 * there is nothing to do since the hash is based on the starting
637 * cluster of the directory file and that hasn't changed. If for a
638 * file the hash is based on the location of the directory entry,
639 * so we must remove it from the cache and re-enter it with the
640 * hash based on the new location of the directory entry.
642 if (dep->de_Attributes & ATTR_DIRECTORY)
644 msdosfs_hashrem(dep);
645 msdosfs_hashins(dep);
650 struct vop_reclaim_args /* {
654 struct vnode *vp = ap->a_vp;
655 struct denode *dep = VTODE(vp);
658 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
659 dep, dep->de_Name, dep->de_refcnt);
662 if (prtactive && vp->v_usecount != 0)
663 vprint("msdosfs_reclaim(): pushing active", vp);
665 * Remove the denode from its hash chain.
667 msdosfs_hashrem(dep);
669 * Purge old data structures associated with the denode.
673 vrele(dep->de_devvp);
679 FREE(dep, M_MSDOSFSNODE);
687 struct vop_inactive_args /* {
692 struct vnode *vp = ap->a_vp;
693 struct denode *dep = VTODE(vp);
697 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
700 if (prtactive && vp->v_usecount != 0)
701 vprint("msdosfs_inactive(): pushing active", vp);
704 * Ignore denodes related to stale file handles.
706 if (dep->de_Name[0] == SLOT_DELETED)
710 * If the file has been deleted and it is on a read/write
711 * filesystem, then truncate the file, and mark the directory slot
712 * as empty. (This may not be necessary for the dos filesystem.)
715 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n",
716 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY);
718 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
719 error = detrunc(dep, (u_long) 0, 0, ap->a_td);
720 dep->de_flag |= DE_UPDATE;
721 dep->de_Name[0] = SLOT_DELETED;
726 VOP_UNLOCK(vp, 0, ap->a_td);
728 * If we are done with the denode, reclaim it
729 * so that it can be reused immediately.
732 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vp->v_usecount,
735 if (dep->de_Name[0] == SLOT_DELETED)
736 vrecycle(vp, NULL, ap->a_td);