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 1.5 2003/07/06 21:23:52 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>
64 #include <msdosfs/bpb.h>
65 #include <msdosfs/msdosfsmount.h>
66 #include <msdosfs/direntry.h>
67 #include <msdosfs/denode.h>
68 #include <msdosfs/fat.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 __P((dev_t dev, u_long dirclust,
98 static void msdosfs_hashins __P((struct denode *dep));
99 static void msdosfs_hashrem __P((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 lwkt_gettoken(&dehash_token);
133 for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) {
134 if (dirclust == dep->de_dirclust
135 && diroff == dep->de_diroffset
136 && dev == dep->de_dev
137 && dep->de_refcnt != 0) {
139 lwkt_gettoken(&vp->v_interlock);
140 lwkt_reltoken(&dehash_token);
141 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td))
146 lwkt_reltoken(&dehash_token);
154 struct denode **depp, *deq;
156 lwkt_gettoken(&dehash_token);
157 depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset);
160 deq->de_prev = &dep->de_next;
164 lwkt_reltoken(&dehash_token);
173 lwkt_gettoken(&dehash_token);
176 deq->de_prev = dep->de_prev;
182 lwkt_reltoken(&dehash_token);
186 * If deget() succeeds it returns with the gotten denode locked().
188 * pmp - address of msdosfsmount structure of the filesystem containing
189 * the denode of interest. The pm_dev field and the address of
190 * the msdosfsmount structure are used.
191 * dirclust - which cluster bp contains, if dirclust is 0 (root directory)
192 * diroffset is relative to the beginning of the root directory,
193 * otherwise it is cluster relative.
194 * diroffset - offset past begin of cluster of denode we want
195 * depp - returns the address of the gotten denode.
198 deget(pmp, dirclust, diroffset, depp)
199 struct msdosfsmount *pmp; /* so we know the maj/min number */
200 u_long dirclust; /* cluster this dir entry came from */
201 u_long diroffset; /* index of entry within the cluster */
202 struct denode **depp; /* returns the addr of the gotten denode */
204 struct thread *td = curthread; /* XXX */
206 dev_t dev = pmp->pm_dev;
207 struct mount *mntp = pmp->pm_mountp;
208 struct direntry *direntptr;
215 printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
216 pmp, dirclust, diroffset, depp);
220 * On FAT32 filesystems, root is a (more or less) normal
223 if (FAT32(pmp) && dirclust == MSDOSFSROOT)
224 dirclust = pmp->pm_rootdirblk;
227 * See if the denode is in the denode cache. Use the location of
228 * the directory entry to compute the hash value. For subdir use
229 * address of "." entry. For root dir (if not FAT32) use cluster
230 * MSDOSFSROOT, offset MSDOSFSROOT_OFS
232 * NOTE: The check for de_refcnt > 0 below insures the denode being
233 * examined does not represent an unlinked but still open file.
234 * These files are not to be accessible even when the directory
235 * entry that represented the file happens to be reused while the
236 * deleted file is still open.
238 ldep = msdosfs_hashget(dev, dirclust, diroffset);
245 * Do the MALLOC before the getnewvnode since doing so afterward
246 * might cause a bogus v_data pointer to get dereferenced
247 * elsewhere if MALLOC should block.
249 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK);
252 * Directory entry was not in cache, have to create a vnode and
253 * copy it from the passed disk buffer.
255 /* getnewvnode() does a VREF() on the vnode */
256 error = getnewvnode(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp);
259 FREE(ldep, M_MSDOSFSNODE);
262 bzero((caddr_t)ldep, sizeof *ldep);
263 lockinit(&ldep->de_lock, PINOD, "denode", VLKTIMEOUT, 0);
265 ldep->de_vnode = nvp;
269 ldep->de_dirclust = dirclust;
270 ldep->de_diroffset = diroffset;
271 fc_purge(ldep, 0); /* init the fat cache for this denode */
274 * Lock the denode so that it can't be accessed until we've read
275 * it in and have done what we need to it. Do this here instead
276 * of at the start of msdosfs_hashins() so that reinsert() can
277 * call msdosfs_hashins() with a locked denode.
279 if (lockmgr(&ldep->de_lock, LK_EXCLUSIVE, NULL, td))
280 panic("deget: unexpected lock failure");
283 * Insert the denode into the hash queue.
285 msdosfs_hashins(ldep);
290 * Copy the directory entry into the denode area of the vnode.
292 if ((dirclust == MSDOSFSROOT
293 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
294 && diroffset == MSDOSFSROOT_OFS) {
296 * Directory entry for the root directory. There isn't one,
297 * so we manufacture one. We should probably rummage
298 * through the root directory and find a label entry (if it
299 * exists), and then use the time and date from that entry
300 * as the time and date for the root denode.
302 nvp->v_flag |= VROOT; /* should be further down XXX */
304 ldep->de_Attributes = ATTR_DIRECTORY;
305 ldep->de_LowerCase = 0;
307 ldep->de_StartCluster = pmp->pm_rootdirblk;
308 /* de_FileSize will be filled in further down */
310 ldep->de_StartCluster = MSDOSFSROOT;
311 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
314 * fill in time and date so that dos2unixtime() doesn't
315 * spit up when called from msdosfs_getattr() with root
319 ldep->de_CTime = 0x0000; /* 00:00:00 */
320 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
321 | (1 << DD_DAY_SHIFT);
323 ldep->de_ADate = ldep->de_CDate;
324 ldep->de_MTime = ldep->de_CTime;
325 ldep->de_MDate = ldep->de_CDate;
326 /* leave the other fields as garbage */
328 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
331 * The denode does not contain anything useful, so
332 * it would be wrong to leave it on its hash chain.
333 * Arrange for vput() to just forget about it.
335 ldep->de_Name[0] = SLOT_DELETED;
341 DE_INTERNALIZE(ldep, direntptr);
346 * Fill in a few fields of the vnode and finish filling in the
347 * denode. Then return the address of the found denode.
349 if (ldep->de_Attributes & ATTR_DIRECTORY) {
351 * Since DOS directory entries that describe directories
352 * have 0 in the filesize field, we take this opportunity
353 * to find out the length of the directory and plug it into
354 * the denode structure.
359 * XXX Sometimes, these arrives that . entry have cluster
360 * number 0, when it shouldn't. Use real cluster number
361 * instead of what is written in directory entry.
363 if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) {
364 printf("deget(): . entry at clust %ld != %ld\n",
365 dirclust, ldep->de_StartCluster);
366 ldep->de_StartCluster = dirclust;
370 if (ldep->de_StartCluster != MSDOSFSROOT) {
371 error = pcbmap(ldep, 0xffff, 0, &size, 0);
372 if (error == E2BIG) {
373 ldep->de_FileSize = de_cn2off(pmp, size);
376 printf("deget(): pcbmap returned %d\n", error);
381 SETHIGH(ldep->de_modrev, tv.tv_sec);
382 SETLOW(ldep->de_modrev, tv.tv_usec * 4294);
383 ldep->de_devvp = pmp->pm_devvp;
384 VREF(ldep->de_devvp);
390 deupdat(dep, waitfor)
396 struct direntry *dirp;
399 if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY)
402 DETIMES(dep, &ts, &ts, &ts);
403 if ((dep->de_flag & DE_MODIFIED) == 0)
405 dep->de_flag &= ~DE_MODIFIED;
406 if (dep->de_Attributes & ATTR_DIRECTORY)
408 if (dep->de_refcnt <= 0)
410 error = readde(dep, &bp, &dirp);
413 DE_EXTERNALIZE(dirp, dep);
423 * Truncate the file described by dep to the length specified by length.
426 detrunc(dep, length, flags, td)
438 int isadir = dep->de_Attributes & ATTR_DIRECTORY;
440 struct msdosfsmount *pmp = dep->de_pmp;
443 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
447 * Disallow attempts to truncate the root directory since it is of
448 * fixed size. That's just the way dos filesystems are. We use
449 * the VROOT bit in the vnode because checking for the directory
450 * bit and a startcluster of 0 in the denode is not adequate to
451 * recognize the root directory at this point in a file or
454 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp)) {
455 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
456 dep->de_dirclust, dep->de_diroffset);
461 if (dep->de_FileSize < length) {
462 vnode_pager_setsize(DETOV(dep), length);
463 return deextend(dep, length);
467 * If the desired length is 0 then remember the starting cluster of
468 * the file and set the StartCluster field in the directory entry
469 * to 0. If the desired length is not zero, then get the number of
470 * the last cluster in the shortened file. Then get the number of
471 * the first cluster in the part of the file that is to be freed.
472 * Then set the next cluster pointer in the last cluster of the
473 * file to CLUST_EOFE.
476 chaintofree = dep->de_StartCluster;
477 dep->de_StartCluster = 0;
480 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0,
484 printf("detrunc(): pcbmap fails %d\n", error);
490 fc_purge(dep, de_clcount(pmp, length));
493 * If the new length is not a multiple of the cluster size then we
494 * must zero the tail end of the new last cluster in case it
495 * becomes part of the file again because of a seek.
497 if ((boff = length & pmp->pm_crbomask) != 0) {
499 bn = cntobn(pmp, eofentry);
500 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, &bp);
502 bn = de_blk(pmp, length);
503 error = bread(DETOV(dep), bn, pmp->pm_bpcluster, &bp);
508 printf("detrunc(): bread fails %d\n", error);
513 * is this the right place for it?
515 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
523 * Write out the updated directory entry. Even if the update fails
524 * we free the trailing clusters.
526 dep->de_FileSize = length;
528 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
529 allerror = vtruncbuf(DETOV(dep), td, length, pmp->pm_bpcluster);
532 printf("detrunc(): vtruncbuf error %d\n", allerror);
534 error = deupdat(dep, 1);
535 if (error && (allerror == 0))
538 printf("detrunc(): allerror %d, eofentry %lu\n",
543 * If we need to break the cluster chain for the file then do it
546 if (eofentry != ~0) {
547 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
548 &chaintofree, CLUST_EOFE);
551 printf("detrunc(): fatentry errors %d\n", error);
555 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
560 * Now free the clusters removed from the file because of the
563 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
564 freeclusterchain(pmp, chaintofree);
570 * Extend the file described by dep to length specified by length.
573 deextend(dep, length)
577 struct msdosfsmount *pmp = dep->de_pmp;
582 * The root of a DOS filesystem cannot be extended.
584 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp))
588 * Directories cannot be extended.
590 if (dep->de_Attributes & ATTR_DIRECTORY)
593 if (length <= dep->de_FileSize)
594 panic("deextend: file too large");
597 * Compute the number of clusters to allocate.
599 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
601 if (count > pmp->pm_freeclustercount)
603 error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
605 /* truncate the added clusters away again */
606 (void) detrunc(dep, dep->de_FileSize, 0, NULL);
610 dep->de_FileSize = length;
611 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
612 return (deupdat(dep, 1));
616 * Move a denode to its correct hash queue after the file it represents has
617 * been moved to a new directory.
624 * Fix up the denode cache. If the denode is for a directory,
625 * there is nothing to do since the hash is based on the starting
626 * cluster of the directory file and that hasn't changed. If for a
627 * file the hash is based on the location of the directory entry,
628 * so we must remove it from the cache and re-enter it with the
629 * hash based on the new location of the directory entry.
631 if (dep->de_Attributes & ATTR_DIRECTORY)
633 msdosfs_hashrem(dep);
634 msdosfs_hashins(dep);
639 struct vop_reclaim_args /* {
643 struct vnode *vp = ap->a_vp;
644 struct denode *dep = VTODE(vp);
647 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
648 dep, dep->de_Name, dep->de_refcnt);
651 if (prtactive && vp->v_usecount != 0)
652 vprint("msdosfs_reclaim(): pushing active", vp);
654 * Remove the denode from its hash chain.
656 msdosfs_hashrem(dep);
658 * Purge old data structures associated with the denode.
662 vrele(dep->de_devvp);
668 FREE(dep, M_MSDOSFSNODE);
676 struct vop_inactive_args /* {
681 struct vnode *vp = ap->a_vp;
682 struct denode *dep = VTODE(vp);
686 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
689 if (prtactive && vp->v_usecount != 0)
690 vprint("msdosfs_inactive(): pushing active", vp);
693 * Ignore denodes related to stale file handles.
695 if (dep->de_Name[0] == SLOT_DELETED)
699 * If the file has been deleted and it is on a read/write
700 * filesystem, then truncate the file, and mark the directory slot
701 * as empty. (This may not be necessary for the dos filesystem.)
704 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n",
705 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY);
707 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
708 error = detrunc(dep, (u_long) 0, 0, ap->a_td);
709 dep->de_flag |= DE_UPDATE;
710 dep->de_Name[0] = SLOT_DELETED;
715 VOP_UNLOCK(vp, 0, ap->a_td);
717 * If we are done with the denode, reclaim it
718 * so that it can be reused immediately.
721 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vp->v_usecount,
724 if (dep->de_Name[0] == SLOT_DELETED)
725 vrecycle(vp, NULL, ap->a_td);