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 1.12 2004/04/24 04:32:04 drhodus 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);
103 msdosfs_init(struct vfsconf *vfsp)
105 dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash);
106 lwkt_token_init(&dehash_token);
111 msdosfs_uninit(struct vfsconf *vfsp)
115 free(dehashtbl, M_MSDOSFSMNT);
119 static struct denode *
120 msdosfs_hashget(dev_t dev, u_long dirclust, u_long diroff)
122 struct thread *td = curthread; /* XXX */
128 lwkt_gettoken(&ilock, &dehash_token);
130 for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) {
131 if (dirclust != dep->de_dirclust
132 || diroff != dep->de_diroffset
133 || dev != dep->de_dev
134 || dep->de_refcnt == 0) {
138 lwkt_gettoken(&vlock, vp->v_interlock);
140 * We must check to see if the inode has been ripped
141 * out from under us after blocking.
143 for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) {
144 if (dirclust == dep->de_dirclust
145 && diroff == dep->de_diroffset
146 && dev == dep->de_dev
147 && dep->de_refcnt != 0) {
151 if (dep == NULL || DETOV(dep) != vp) {
152 lwkt_reltoken(&vlock);
155 if (vget(vp, &vlock, LK_EXCLUSIVE | LK_INTERLOCK, td))
157 lwkt_reltoken(&ilock);
160 lwkt_reltoken(&ilock);
165 msdosfs_hashins(struct denode *dep)
167 struct denode **depp, *deq;
170 lwkt_gettoken(&ilock, &dehash_token);
171 depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset);
174 deq->de_prev = &dep->de_next;
178 lwkt_reltoken(&ilock);
182 msdosfs_hashrem(struct denode *dep)
187 lwkt_gettoken(&ilock, &dehash_token);
190 deq->de_prev = dep->de_prev;
196 lwkt_reltoken(&ilock);
200 * If deget() succeeds it returns with the gotten denode locked().
202 * pmp - address of msdosfsmount structure of the filesystem containing
203 * the denode of interest. The pm_dev field and the address of
204 * the msdosfsmount structure are used.
205 * dirclust - which cluster bp contains, if dirclust is 0 (root directory)
206 * diroffset is relative to the beginning of the root directory,
207 * otherwise it is cluster relative.
208 * diroffset - offset past begin of cluster of denode we want
209 * depp - returns the address of the gotten denode.
212 deget(struct msdosfsmount *pmp, /* so we know the maj/min number */
213 u_long dirclust, /* cluster this dir entry came from */
214 u_long diroffset, /* index of entry within the cluster */
215 struct denode **depp) /* returns the addr of the gotten denode */
217 struct thread *td = curthread; /* XXX */
219 dev_t dev = pmp->pm_dev;
220 struct mount *mntp = pmp->pm_mountp;
221 struct direntry *direntptr;
228 printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
229 pmp, dirclust, diroffset, depp);
233 * On FAT32 filesystems, root is a (more or less) normal
236 if (FAT32(pmp) && dirclust == MSDOSFSROOT)
237 dirclust = pmp->pm_rootdirblk;
240 * See if the denode is in the denode cache. Use the location of
241 * the directory entry to compute the hash value. For subdir use
242 * address of "." entry. For root dir (if not FAT32) use cluster
243 * MSDOSFSROOT, offset MSDOSFSROOT_OFS
245 * NOTE: The check for de_refcnt > 0 below insures the denode being
246 * examined does not represent an unlinked but still open file.
247 * These files are not to be accessible even when the directory
248 * entry that represented the file happens to be reused while the
249 * deleted file is still open.
251 ldep = msdosfs_hashget(dev, dirclust, diroffset);
258 * Do the MALLOC before the getnewvnode since doing so afterward
259 * might cause a bogus v_data pointer to get dereferenced
260 * elsewhere if MALLOC should block.
262 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK);
265 * Directory entry was not in cache, have to create a vnode and
266 * copy it from the passed disk buffer.
268 /* getnewvnode() does a vref() on the vnode */
269 error = getnewvnode(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp);
272 FREE(ldep, M_MSDOSFSNODE);
275 bzero((caddr_t)ldep, sizeof *ldep);
276 lockinit(&ldep->de_lock, 0, "denode", VLKTIMEOUT, 0);
278 ldep->de_vnode = nvp;
282 ldep->de_dirclust = dirclust;
283 ldep->de_diroffset = diroffset;
284 fc_purge(ldep, 0); /* init the fat cache for this denode */
287 * Lock the denode so that it can't be accessed until we've read
288 * it in and have done what we need to it. Do this here instead
289 * of at the start of msdosfs_hashins() so that reinsert() can
290 * call msdosfs_hashins() with a locked denode.
292 if (lockmgr(&ldep->de_lock, LK_EXCLUSIVE, NULL, td))
293 panic("deget: unexpected lock failure");
296 * Insert the denode into the hash queue.
298 msdosfs_hashins(ldep);
303 * Copy the directory entry into the denode area of the vnode.
305 if ((dirclust == MSDOSFSROOT
306 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
307 && diroffset == MSDOSFSROOT_OFS) {
309 * Directory entry for the root directory. There isn't one,
310 * so we manufacture one. We should probably rummage
311 * through the root directory and find a label entry (if it
312 * exists), and then use the time and date from that entry
313 * as the time and date for the root denode.
315 nvp->v_flag |= VROOT; /* should be further down XXX */
317 ldep->de_Attributes = ATTR_DIRECTORY;
318 ldep->de_LowerCase = 0;
320 ldep->de_StartCluster = pmp->pm_rootdirblk;
321 /* de_FileSize will be filled in further down */
323 ldep->de_StartCluster = MSDOSFSROOT;
324 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
327 * fill in time and date so that dos2unixtime() doesn't
328 * spit up when called from msdosfs_getattr() with root
332 ldep->de_CTime = 0x0000; /* 00:00:00 */
333 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
334 | (1 << DD_DAY_SHIFT);
336 ldep->de_ADate = ldep->de_CDate;
337 ldep->de_MTime = ldep->de_CTime;
338 ldep->de_MDate = ldep->de_CDate;
339 /* leave the other fields as garbage */
341 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
344 * The denode does not contain anything useful, so
345 * it would be wrong to leave it on its hash chain.
346 * Arrange for vput() to just forget about it.
348 ldep->de_Name[0] = SLOT_DELETED;
354 DE_INTERNALIZE(ldep, direntptr);
359 * Fill in a few fields of the vnode and finish filling in the
360 * denode. Then return the address of the found denode.
362 if (ldep->de_Attributes & ATTR_DIRECTORY) {
364 * Since DOS directory entries that describe directories
365 * have 0 in the filesize field, we take this opportunity
366 * to find out the length of the directory and plug it into
367 * the denode structure.
372 * XXX Sometimes, these arrives that . entry have cluster
373 * number 0, when it shouldn't. Use real cluster number
374 * instead of what is written in directory entry.
376 if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) {
377 printf("deget(): . entry at clust %ld != %ld\n",
378 dirclust, ldep->de_StartCluster);
379 ldep->de_StartCluster = dirclust;
383 if (ldep->de_StartCluster != MSDOSFSROOT) {
384 error = pcbmap(ldep, 0xffff, 0, &size, 0);
385 if (error == E2BIG) {
386 ldep->de_FileSize = de_cn2off(pmp, size);
389 printf("deget(): pcbmap returned %d\n", error);
394 SETHIGH(ldep->de_modrev, tv.tv_sec);
395 SETLOW(ldep->de_modrev, tv.tv_usec * 4294);
396 ldep->de_devvp = pmp->pm_devvp;
397 vref(ldep->de_devvp);
403 deupdat(struct denode *dep, int 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(struct denode *dep, u_long length, int flags, struct thread *td)
445 int isadir = dep->de_Attributes & ATTR_DIRECTORY;
447 struct msdosfsmount *pmp = dep->de_pmp;
450 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
454 * Disallow attempts to truncate the root directory since it is of
455 * fixed size. That's just the way dos filesystems are. We use
456 * the VROOT bit in the vnode because checking for the directory
457 * bit and a startcluster of 0 in the denode is not adequate to
458 * recognize the root directory at this point in a file or
461 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp)) {
462 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
463 dep->de_dirclust, dep->de_diroffset);
468 if (dep->de_FileSize < length) {
469 vnode_pager_setsize(DETOV(dep), length);
470 return deextend(dep, length);
474 * If the desired length is 0 then remember the starting cluster of
475 * the file and set the StartCluster field in the directory entry
476 * to 0. If the desired length is not zero, then get the number of
477 * the last cluster in the shortened file. Then get the number of
478 * the first cluster in the part of the file that is to be freed.
479 * Then set the next cluster pointer in the last cluster of the
480 * file to CLUST_EOFE.
483 chaintofree = dep->de_StartCluster;
484 dep->de_StartCluster = 0;
487 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0,
491 printf("detrunc(): pcbmap fails %d\n", error);
497 fc_purge(dep, de_clcount(pmp, length));
500 * If the new length is not a multiple of the cluster size then we
501 * must zero the tail end of the new last cluster in case it
502 * becomes part of the file again because of a seek.
504 if ((boff = length & pmp->pm_crbomask) != 0) {
506 bn = cntobn(pmp, eofentry);
507 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, &bp);
509 bn = de_blk(pmp, length);
510 error = bread(DETOV(dep), bn, pmp->pm_bpcluster, &bp);
515 printf("detrunc(): bread fails %d\n", error);
520 * is this the right place for it?
522 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
530 * Write out the updated directory entry. Even if the update fails
531 * we free the trailing clusters.
533 dep->de_FileSize = length;
535 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
536 allerror = vtruncbuf(DETOV(dep), td, length, pmp->pm_bpcluster);
539 printf("detrunc(): vtruncbuf error %d\n", allerror);
541 error = deupdat(dep, 1);
542 if (error && (allerror == 0))
545 printf("detrunc(): allerror %d, eofentry %lu\n",
550 * If we need to break the cluster chain for the file then do it
553 if (eofentry != ~0) {
554 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
555 &chaintofree, CLUST_EOFE);
558 printf("detrunc(): fatentry errors %d\n", error);
562 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
567 * Now free the clusters removed from the file because of the
570 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
571 freeclusterchain(pmp, chaintofree);
577 * Extend the file described by dep to length specified by length.
580 deextend(struct denode *dep, u_long length)
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, 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.
625 reinsert(struct denode *dep)
628 * Fix up the denode cache. If the denode is for a directory,
629 * there is nothing to do since the hash is based on the starting
630 * cluster of the directory file and that hasn't changed. If for a
631 * file the hash is based on the location of the directory entry,
632 * so we must remove it from the cache and re-enter it with the
633 * hash based on the new location of the directory entry.
635 if (dep->de_Attributes & ATTR_DIRECTORY)
637 msdosfs_hashrem(dep);
638 msdosfs_hashins(dep);
642 * msdosfs_reclaim(struct vnode *a_vp)
645 msdosfs_reclaim(struct vop_reclaim_args *ap)
647 struct vnode *vp = ap->a_vp;
648 struct denode *dep = VTODE(vp);
651 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
652 dep, dep->de_Name, dep->de_refcnt);
655 if (prtactive && vp->v_usecount != 0)
656 vprint("msdosfs_reclaim(): pushing active", vp);
658 * Remove the denode from its hash chain.
660 msdosfs_hashrem(dep);
662 * Purge old data structures associated with the denode.
666 vrele(dep->de_devvp);
672 FREE(dep, M_MSDOSFSNODE);
679 * msdosfs_inactive(struct vnode *a_vp, struct thread *a_td)
682 msdosfs_inactive(struct vop_inactive_args *ap)
684 struct vnode *vp = ap->a_vp;
685 struct denode *dep = VTODE(vp);
689 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
692 if (prtactive && vp->v_usecount != 0)
693 vprint("msdosfs_inactive(): pushing active", vp);
696 * Ignore denodes related to stale file handles.
698 if (dep->de_Name[0] == SLOT_DELETED)
702 * If the file has been deleted and it is on a read/write
703 * filesystem, then truncate the file, and mark the directory slot
704 * as empty. (This may not be necessary for the dos filesystem.)
707 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n",
708 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY);
710 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
711 error = detrunc(dep, (u_long) 0, 0, ap->a_td);
712 dep->de_flag |= DE_UPDATE;
713 dep->de_Name[0] = SLOT_DELETED;
718 VOP_UNLOCK(vp, NULL, 0, ap->a_td);
720 * If we are done with the denode, reclaim it
721 * so that it can be reused immediately.
724 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vp->v_usecount,
727 if (dep->de_Name[0] == SLOT_DELETED)
728 vrecycle(vp, NULL, ap->a_td);