1 /* $FreeBSD: src/sys/msdosfs/msdosfs_denode.c,v 1.47.2.3 2002/08/22 16:20:15 trhodes Exp $ */
2 /* $NetBSD: msdosfs_denode.c,v 1.28 1998/02/10 14:10:00 mrg Exp $ */
5 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
6 * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
8 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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.
36 * Written by Paul Popelka (paulp@uts.amdahl.com)
38 * You can do anything you want with this software, just don't say you wrote
39 * it, and don't remove this notice.
41 * This software is provided "as is".
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.
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>
58 #include <sys/vnode.h>
61 #include <vm/vm_extern.h>
63 #include <msdosfs/bpb.h>
64 #include <msdosfs/msdosfsmount.h>
65 #include <msdosfs/direntry.h>
66 #include <msdosfs/denode.h>
67 #include <msdosfs/fat.h>
69 static MALLOC_DEFINE(M_MSDOSFSNODE, "MSDOSFS node", "MSDOSFS vnode private part");
71 static struct denode **dehashtbl;
72 static u_long dehash; /* size of hash table - 1 */
73 #define DEHASH(dev, dcl, doff) (dehashtbl[(minor(dev) + (dcl) + (doff) / \
74 sizeof(struct direntry)) & dehash])
75 #ifndef NULL_SIMPLELOCKS
76 static struct simplelock dehash_slock;
83 #define SETHIGH(q, h) { \
86 tmp.val[_QUAD_HIGHWORD] = (h); \
89 #define SETLOW(q, l) { \
92 tmp.val[_QUAD_LOWWORD] = (l); \
96 static struct denode *
97 msdosfs_hashget __P((dev_t dev, u_long dirclust,
99 static void msdosfs_hashins __P((struct denode *dep));
100 static void msdosfs_hashrem __P((struct denode *dep));
105 struct vfsconf *vfsp;
107 dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash);
108 simple_lock_init(&dehash_slock);
114 struct vfsconf *vfsp;
118 free(dehashtbl, M_MSDOSFSMNT);
122 static struct denode *
123 msdosfs_hashget(dev, dirclust, diroff)
128 struct proc *p = curproc; /* XXX */
133 simple_lock(&dehash_slock);
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 simple_lock(&vp->v_interlock);
141 simple_unlock(&dehash_slock);
142 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, p))
147 simple_unlock(&dehash_slock);
155 struct denode **depp, *deq;
157 simple_lock(&dehash_slock);
158 depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset);
161 deq->de_prev = &dep->de_next;
165 simple_unlock(&dehash_slock);
174 simple_lock(&dehash_slock);
177 deq->de_prev = dep->de_prev;
183 simple_unlock(&dehash_slock);
187 * If deget() succeeds it returns with the gotten denode locked().
189 * pmp - address of msdosfsmount structure of the filesystem containing
190 * the denode of interest. The pm_dev field and the address of
191 * the msdosfsmount structure are used.
192 * dirclust - which cluster bp contains, if dirclust is 0 (root directory)
193 * diroffset is relative to the beginning of the root directory,
194 * otherwise it is cluster relative.
195 * diroffset - offset past begin of cluster of denode we want
196 * depp - returns the address of the gotten denode.
199 deget(pmp, dirclust, diroffset, depp)
200 struct msdosfsmount *pmp; /* so we know the maj/min number */
201 u_long dirclust; /* cluster this dir entry came from */
202 u_long diroffset; /* index of entry within the cluster */
203 struct denode **depp; /* returns the addr of the gotten denode */
206 dev_t dev = pmp->pm_dev;
207 struct mount *mntp = pmp->pm_mountp;
208 struct direntry *direntptr;
212 struct proc *p = curproc; /* XXX */
216 printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
217 pmp, dirclust, diroffset, depp);
221 * On FAT32 filesystems, root is a (more or less) normal
224 if (FAT32(pmp) && dirclust == MSDOSFSROOT)
225 dirclust = pmp->pm_rootdirblk;
228 * See if the denode is in the denode cache. Use the location of
229 * the directory entry to compute the hash value. For subdir use
230 * address of "." entry. For root dir (if not FAT32) use cluster
231 * MSDOSFSROOT, offset MSDOSFSROOT_OFS
233 * NOTE: The check for de_refcnt > 0 below insures the denode being
234 * examined does not represent an unlinked but still open file.
235 * These files are not to be accessible even when the directory
236 * entry that represented the file happens to be reused while the
237 * deleted file is still open.
239 ldep = msdosfs_hashget(dev, dirclust, diroffset);
246 * Do the MALLOC before the getnewvnode since doing so afterward
247 * might cause a bogus v_data pointer to get dereferenced
248 * elsewhere if MALLOC should block.
250 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK);
253 * Directory entry was not in cache, have to create a vnode and
254 * copy it from the passed disk buffer.
256 /* getnewvnode() does a VREF() on the vnode */
257 error = getnewvnode(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp);
260 FREE(ldep, M_MSDOSFSNODE);
263 bzero((caddr_t)ldep, sizeof *ldep);
264 lockinit(&ldep->de_lock, PINOD, "denode", VLKTIMEOUT, 0);
266 ldep->de_vnode = nvp;
270 ldep->de_dirclust = dirclust;
271 ldep->de_diroffset = diroffset;
272 fc_purge(ldep, 0); /* init the fat cache for this denode */
275 * Lock the denode so that it can't be accessed until we've read
276 * it in and have done what we need to it. Do this here instead
277 * of at the start of msdosfs_hashins() so that reinsert() can
278 * call msdosfs_hashins() with a locked denode.
280 if (lockmgr(&ldep->de_lock, LK_EXCLUSIVE, (struct simplelock *)0, p))
281 panic("deget: unexpected lock failure");
284 * Insert the denode into the hash queue.
286 msdosfs_hashins(ldep);
291 * Copy the directory entry into the denode area of the vnode.
293 if ((dirclust == MSDOSFSROOT
294 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
295 && diroffset == MSDOSFSROOT_OFS) {
297 * Directory entry for the root directory. There isn't one,
298 * so we manufacture one. We should probably rummage
299 * through the root directory and find a label entry (if it
300 * exists), and then use the time and date from that entry
301 * as the time and date for the root denode.
303 nvp->v_flag |= VROOT; /* should be further down XXX */
305 ldep->de_Attributes = ATTR_DIRECTORY;
306 ldep->de_LowerCase = 0;
308 ldep->de_StartCluster = pmp->pm_rootdirblk;
309 /* de_FileSize will be filled in further down */
311 ldep->de_StartCluster = MSDOSFSROOT;
312 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
315 * fill in time and date so that dos2unixtime() doesn't
316 * spit up when called from msdosfs_getattr() with root
320 ldep->de_CTime = 0x0000; /* 00:00:00 */
321 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
322 | (1 << DD_DAY_SHIFT);
324 ldep->de_ADate = ldep->de_CDate;
325 ldep->de_MTime = ldep->de_CTime;
326 ldep->de_MDate = ldep->de_CDate;
327 /* leave the other fields as garbage */
329 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
332 * The denode does not contain anything useful, so
333 * it would be wrong to leave it on its hash chain.
334 * Arrange for vput() to just forget about it.
336 ldep->de_Name[0] = SLOT_DELETED;
342 DE_INTERNALIZE(ldep, direntptr);
347 * Fill in a few fields of the vnode and finish filling in the
348 * denode. Then return the address of the found denode.
350 if (ldep->de_Attributes & ATTR_DIRECTORY) {
352 * Since DOS directory entries that describe directories
353 * have 0 in the filesize field, we take this opportunity
354 * to find out the length of the directory and plug it into
355 * the denode structure.
360 * XXX Sometimes, these arrives that . entry have cluster
361 * number 0, when it shouldn't. Use real cluster number
362 * instead of what is written in directory entry.
364 if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) {
365 printf("deget(): . entry at clust %ld != %ld\n",
366 dirclust, ldep->de_StartCluster);
367 ldep->de_StartCluster = dirclust;
371 if (ldep->de_StartCluster != MSDOSFSROOT) {
372 error = pcbmap(ldep, 0xffff, 0, &size, 0);
373 if (error == E2BIG) {
374 ldep->de_FileSize = de_cn2off(pmp, size);
377 printf("deget(): pcbmap returned %d\n", error);
382 SETHIGH(ldep->de_modrev, tv.tv_sec);
383 SETLOW(ldep->de_modrev, tv.tv_usec * 4294);
384 ldep->de_devvp = pmp->pm_devvp;
385 VREF(ldep->de_devvp);
391 deupdat(dep, waitfor)
397 struct direntry *dirp;
400 if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY)
403 DETIMES(dep, &ts, &ts, &ts);
404 if ((dep->de_flag & DE_MODIFIED) == 0)
406 dep->de_flag &= ~DE_MODIFIED;
407 if (dep->de_Attributes & ATTR_DIRECTORY)
409 if (dep->de_refcnt <= 0)
411 error = readde(dep, &bp, &dirp);
414 DE_EXTERNALIZE(dirp, dep);
424 * Truncate the file described by dep to the length specified by length.
427 detrunc(dep, length, flags, cred, p)
440 int isadir = dep->de_Attributes & ATTR_DIRECTORY;
442 struct msdosfsmount *pmp = dep->de_pmp;
445 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
449 * Disallow attempts to truncate the root directory since it is of
450 * fixed size. That's just the way dos filesystems are. We use
451 * the VROOT bit in the vnode because checking for the directory
452 * bit and a startcluster of 0 in the denode is not adequate to
453 * recognize the root directory at this point in a file or
456 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp)) {
457 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
458 dep->de_dirclust, dep->de_diroffset);
463 if (dep->de_FileSize < length) {
464 vnode_pager_setsize(DETOV(dep), length);
465 return deextend(dep, length, cred);
469 * If the desired length is 0 then remember the starting cluster of
470 * the file and set the StartCluster field in the directory entry
471 * to 0. If the desired length is not zero, then get the number of
472 * the last cluster in the shortened file. Then get the number of
473 * the first cluster in the part of the file that is to be freed.
474 * Then set the next cluster pointer in the last cluster of the
475 * file to CLUST_EOFE.
478 chaintofree = dep->de_StartCluster;
479 dep->de_StartCluster = 0;
482 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0,
486 printf("detrunc(): pcbmap fails %d\n", error);
492 fc_purge(dep, de_clcount(pmp, length));
495 * If the new length is not a multiple of the cluster size then we
496 * must zero the tail end of the new last cluster in case it
497 * becomes part of the file again because of a seek.
499 if ((boff = length & pmp->pm_crbomask) != 0) {
501 bn = cntobn(pmp, eofentry);
502 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
505 bn = de_blk(pmp, length);
506 error = bread(DETOV(dep), bn, pmp->pm_bpcluster,
512 printf("detrunc(): bread fails %d\n", error);
517 * is this the right place for it?
519 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
527 * Write out the updated directory entry. Even if the update fails
528 * we free the trailing clusters.
530 dep->de_FileSize = length;
532 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
533 allerror = vtruncbuf(DETOV(dep), cred, p, length, pmp->pm_bpcluster);
536 printf("detrunc(): vtruncbuf error %d\n", allerror);
538 error = deupdat(dep, 1);
539 if (error && (allerror == 0))
542 printf("detrunc(): allerror %d, eofentry %lu\n",
547 * If we need to break the cluster chain for the file then do it
550 if (eofentry != ~0) {
551 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
552 &chaintofree, CLUST_EOFE);
555 printf("detrunc(): fatentry errors %d\n", error);
559 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
564 * Now free the clusters removed from the file because of the
567 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
568 freeclusterchain(pmp, chaintofree);
574 * Extend the file described by dep to length specified by length.
577 deextend(dep, length, cred)
582 struct msdosfsmount *pmp = dep->de_pmp;
587 * The root of a DOS filesystem cannot be extended.
589 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp))
593 * Directories cannot be extended.
595 if (dep->de_Attributes & ATTR_DIRECTORY)
598 if (length <= dep->de_FileSize)
599 panic("deextend: file too large");
602 * Compute the number of clusters to allocate.
604 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
606 if (count > pmp->pm_freeclustercount)
608 error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
610 /* truncate the added clusters away again */
611 (void) detrunc(dep, dep->de_FileSize, 0, cred, NULL);
615 dep->de_FileSize = length;
616 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
617 return (deupdat(dep, 1));
621 * Move a denode to its correct hash queue after the file it represents has
622 * been moved to a new directory.
629 * Fix up the denode cache. If the denode is for a directory,
630 * there is nothing to do since the hash is based on the starting
631 * cluster of the directory file and that hasn't changed. If for a
632 * file the hash is based on the location of the directory entry,
633 * so we must remove it from the cache and re-enter it with the
634 * hash based on the new location of the directory entry.
636 if (dep->de_Attributes & ATTR_DIRECTORY)
638 msdosfs_hashrem(dep);
639 msdosfs_hashins(dep);
644 struct vop_reclaim_args /* {
648 struct vnode *vp = ap->a_vp;
649 struct denode *dep = VTODE(vp);
652 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
653 dep, dep->de_Name, dep->de_refcnt);
656 if (prtactive && vp->v_usecount != 0)
657 vprint("msdosfs_reclaim(): pushing active", vp);
659 * Remove the denode from its hash chain.
661 msdosfs_hashrem(dep);
663 * Purge old data structures associated with the denode.
667 vrele(dep->de_devvp);
673 FREE(dep, M_MSDOSFSNODE);
681 struct vop_inactive_args /* {
686 struct vnode *vp = ap->a_vp;
687 struct denode *dep = VTODE(vp);
688 struct proc *p = ap->a_p;
692 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
695 if (prtactive && vp->v_usecount != 0)
696 vprint("msdosfs_inactive(): pushing active", vp);
699 * Ignore denodes related to stale file handles.
701 if (dep->de_Name[0] == SLOT_DELETED)
705 * If the file has been deleted and it is on a read/write
706 * filesystem, then truncate the file, and mark the directory slot
707 * as empty. (This may not be necessary for the dos filesystem.)
710 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n",
711 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY);
713 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
714 error = detrunc(dep, (u_long) 0, 0, NOCRED, p);
715 dep->de_flag |= DE_UPDATE;
716 dep->de_Name[0] = SLOT_DELETED;
721 VOP_UNLOCK(vp, 0, p);
723 * If we are done with the denode, reclaim it
724 * so that it can be reused immediately.
727 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vp->v_usecount,
730 if (dep->de_Name[0] == SLOT_DELETED)
731 vrecycle(vp, (struct simplelock *)0, p);