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 1.2 2003/06/17 04:28:47 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 #ifndef NULL_SIMPLELOCKS
77 static struct simplelock dehash_slock;
84 #define SETHIGH(q, h) { \
87 tmp.val[_QUAD_HIGHWORD] = (h); \
90 #define SETLOW(q, l) { \
93 tmp.val[_QUAD_LOWWORD] = (l); \
97 static struct denode *
98 msdosfs_hashget __P((dev_t dev, u_long dirclust,
100 static void msdosfs_hashins __P((struct denode *dep));
101 static void msdosfs_hashrem __P((struct denode *dep));
106 struct vfsconf *vfsp;
108 dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash);
109 simple_lock_init(&dehash_slock);
115 struct vfsconf *vfsp;
119 free(dehashtbl, M_MSDOSFSMNT);
123 static struct denode *
124 msdosfs_hashget(dev, dirclust, diroff)
129 struct proc *p = curproc; /* XXX */
134 simple_lock(&dehash_slock);
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) {
141 simple_lock(&vp->v_interlock);
142 simple_unlock(&dehash_slock);
143 if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, p))
148 simple_unlock(&dehash_slock);
156 struct denode **depp, *deq;
158 simple_lock(&dehash_slock);
159 depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset);
162 deq->de_prev = &dep->de_next;
166 simple_unlock(&dehash_slock);
175 simple_lock(&dehash_slock);
178 deq->de_prev = dep->de_prev;
184 simple_unlock(&dehash_slock);
188 * If deget() succeeds it returns with the gotten denode locked().
190 * pmp - address of msdosfsmount structure of the filesystem containing
191 * the denode of interest. The pm_dev field and the address of
192 * the msdosfsmount structure are used.
193 * dirclust - which cluster bp contains, if dirclust is 0 (root directory)
194 * diroffset is relative to the beginning of the root directory,
195 * otherwise it is cluster relative.
196 * diroffset - offset past begin of cluster of denode we want
197 * depp - returns the address of the gotten denode.
200 deget(pmp, dirclust, diroffset, depp)
201 struct msdosfsmount *pmp; /* so we know the maj/min number */
202 u_long dirclust; /* cluster this dir entry came from */
203 u_long diroffset; /* index of entry within the cluster */
204 struct denode **depp; /* returns the addr of the gotten denode */
207 dev_t dev = pmp->pm_dev;
208 struct mount *mntp = pmp->pm_mountp;
209 struct direntry *direntptr;
213 struct proc *p = curproc; /* XXX */
217 printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
218 pmp, dirclust, diroffset, depp);
222 * On FAT32 filesystems, root is a (more or less) normal
225 if (FAT32(pmp) && dirclust == MSDOSFSROOT)
226 dirclust = pmp->pm_rootdirblk;
229 * See if the denode is in the denode cache. Use the location of
230 * the directory entry to compute the hash value. For subdir use
231 * address of "." entry. For root dir (if not FAT32) use cluster
232 * MSDOSFSROOT, offset MSDOSFSROOT_OFS
234 * NOTE: The check for de_refcnt > 0 below insures the denode being
235 * examined does not represent an unlinked but still open file.
236 * These files are not to be accessible even when the directory
237 * entry that represented the file happens to be reused while the
238 * deleted file is still open.
240 ldep = msdosfs_hashget(dev, dirclust, diroffset);
247 * Do the MALLOC before the getnewvnode since doing so afterward
248 * might cause a bogus v_data pointer to get dereferenced
249 * elsewhere if MALLOC should block.
251 MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK);
254 * Directory entry was not in cache, have to create a vnode and
255 * copy it from the passed disk buffer.
257 /* getnewvnode() does a VREF() on the vnode */
258 error = getnewvnode(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp);
261 FREE(ldep, M_MSDOSFSNODE);
264 bzero((caddr_t)ldep, sizeof *ldep);
265 lockinit(&ldep->de_lock, PINOD, "denode", VLKTIMEOUT, 0);
267 ldep->de_vnode = nvp;
271 ldep->de_dirclust = dirclust;
272 ldep->de_diroffset = diroffset;
273 fc_purge(ldep, 0); /* init the fat cache for this denode */
276 * Lock the denode so that it can't be accessed until we've read
277 * it in and have done what we need to it. Do this here instead
278 * of at the start of msdosfs_hashins() so that reinsert() can
279 * call msdosfs_hashins() with a locked denode.
281 if (lockmgr(&ldep->de_lock, LK_EXCLUSIVE, (struct simplelock *)0, p))
282 panic("deget: unexpected lock failure");
285 * Insert the denode into the hash queue.
287 msdosfs_hashins(ldep);
292 * Copy the directory entry into the denode area of the vnode.
294 if ((dirclust == MSDOSFSROOT
295 || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
296 && diroffset == MSDOSFSROOT_OFS) {
298 * Directory entry for the root directory. There isn't one,
299 * so we manufacture one. We should probably rummage
300 * through the root directory and find a label entry (if it
301 * exists), and then use the time and date from that entry
302 * as the time and date for the root denode.
304 nvp->v_flag |= VROOT; /* should be further down XXX */
306 ldep->de_Attributes = ATTR_DIRECTORY;
307 ldep->de_LowerCase = 0;
309 ldep->de_StartCluster = pmp->pm_rootdirblk;
310 /* de_FileSize will be filled in further down */
312 ldep->de_StartCluster = MSDOSFSROOT;
313 ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
316 * fill in time and date so that dos2unixtime() doesn't
317 * spit up when called from msdosfs_getattr() with root
321 ldep->de_CTime = 0x0000; /* 00:00:00 */
322 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
323 | (1 << DD_DAY_SHIFT);
325 ldep->de_ADate = ldep->de_CDate;
326 ldep->de_MTime = ldep->de_CTime;
327 ldep->de_MDate = ldep->de_CDate;
328 /* leave the other fields as garbage */
330 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
333 * The denode does not contain anything useful, so
334 * it would be wrong to leave it on its hash chain.
335 * Arrange for vput() to just forget about it.
337 ldep->de_Name[0] = SLOT_DELETED;
343 DE_INTERNALIZE(ldep, direntptr);
348 * Fill in a few fields of the vnode and finish filling in the
349 * denode. Then return the address of the found denode.
351 if (ldep->de_Attributes & ATTR_DIRECTORY) {
353 * Since DOS directory entries that describe directories
354 * have 0 in the filesize field, we take this opportunity
355 * to find out the length of the directory and plug it into
356 * the denode structure.
361 * XXX Sometimes, these arrives that . entry have cluster
362 * number 0, when it shouldn't. Use real cluster number
363 * instead of what is written in directory entry.
365 if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) {
366 printf("deget(): . entry at clust %ld != %ld\n",
367 dirclust, ldep->de_StartCluster);
368 ldep->de_StartCluster = dirclust;
372 if (ldep->de_StartCluster != MSDOSFSROOT) {
373 error = pcbmap(ldep, 0xffff, 0, &size, 0);
374 if (error == E2BIG) {
375 ldep->de_FileSize = de_cn2off(pmp, size);
378 printf("deget(): pcbmap returned %d\n", error);
383 SETHIGH(ldep->de_modrev, tv.tv_sec);
384 SETLOW(ldep->de_modrev, tv.tv_usec * 4294);
385 ldep->de_devvp = pmp->pm_devvp;
386 VREF(ldep->de_devvp);
392 deupdat(dep, waitfor)
398 struct direntry *dirp;
401 if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY)
404 DETIMES(dep, &ts, &ts, &ts);
405 if ((dep->de_flag & DE_MODIFIED) == 0)
407 dep->de_flag &= ~DE_MODIFIED;
408 if (dep->de_Attributes & ATTR_DIRECTORY)
410 if (dep->de_refcnt <= 0)
412 error = readde(dep, &bp, &dirp);
415 DE_EXTERNALIZE(dirp, dep);
425 * Truncate the file described by dep to the length specified by length.
428 detrunc(dep, length, flags, cred, p)
441 int isadir = dep->de_Attributes & ATTR_DIRECTORY;
443 struct msdosfsmount *pmp = dep->de_pmp;
446 printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
450 * Disallow attempts to truncate the root directory since it is of
451 * fixed size. That's just the way dos filesystems are. We use
452 * the VROOT bit in the vnode because checking for the directory
453 * bit and a startcluster of 0 in the denode is not adequate to
454 * recognize the root directory at this point in a file or
457 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp)) {
458 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
459 dep->de_dirclust, dep->de_diroffset);
464 if (dep->de_FileSize < length) {
465 vnode_pager_setsize(DETOV(dep), length);
466 return deextend(dep, length, cred);
470 * If the desired length is 0 then remember the starting cluster of
471 * the file and set the StartCluster field in the directory entry
472 * to 0. If the desired length is not zero, then get the number of
473 * the last cluster in the shortened file. Then get the number of
474 * the first cluster in the part of the file that is to be freed.
475 * Then set the next cluster pointer in the last cluster of the
476 * file to CLUST_EOFE.
479 chaintofree = dep->de_StartCluster;
480 dep->de_StartCluster = 0;
483 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0,
487 printf("detrunc(): pcbmap fails %d\n", error);
493 fc_purge(dep, de_clcount(pmp, length));
496 * If the new length is not a multiple of the cluster size then we
497 * must zero the tail end of the new last cluster in case it
498 * becomes part of the file again because of a seek.
500 if ((boff = length & pmp->pm_crbomask) != 0) {
502 bn = cntobn(pmp, eofentry);
503 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
506 bn = de_blk(pmp, length);
507 error = bread(DETOV(dep), bn, pmp->pm_bpcluster,
513 printf("detrunc(): bread fails %d\n", error);
518 * is this the right place for it?
520 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
528 * Write out the updated directory entry. Even if the update fails
529 * we free the trailing clusters.
531 dep->de_FileSize = length;
533 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
534 allerror = vtruncbuf(DETOV(dep), cred, p, length, pmp->pm_bpcluster);
537 printf("detrunc(): vtruncbuf error %d\n", allerror);
539 error = deupdat(dep, 1);
540 if (error && (allerror == 0))
543 printf("detrunc(): allerror %d, eofentry %lu\n",
548 * If we need to break the cluster chain for the file then do it
551 if (eofentry != ~0) {
552 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
553 &chaintofree, CLUST_EOFE);
556 printf("detrunc(): fatentry errors %d\n", error);
560 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
565 * Now free the clusters removed from the file because of the
568 if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
569 freeclusterchain(pmp, chaintofree);
575 * Extend the file described by dep to length specified by length.
578 deextend(dep, length, cred)
583 struct msdosfsmount *pmp = dep->de_pmp;
588 * The root of a DOS filesystem cannot be extended.
590 if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp))
594 * Directories cannot be extended.
596 if (dep->de_Attributes & ATTR_DIRECTORY)
599 if (length <= dep->de_FileSize)
600 panic("deextend: file too large");
603 * Compute the number of clusters to allocate.
605 count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
607 if (count > pmp->pm_freeclustercount)
609 error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
611 /* truncate the added clusters away again */
612 (void) detrunc(dep, dep->de_FileSize, 0, cred, NULL);
616 dep->de_FileSize = length;
617 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
618 return (deupdat(dep, 1));
622 * Move a denode to its correct hash queue after the file it represents has
623 * been moved to a new directory.
630 * Fix up the denode cache. If the denode is for a directory,
631 * there is nothing to do since the hash is based on the starting
632 * cluster of the directory file and that hasn't changed. If for a
633 * file the hash is based on the location of the directory entry,
634 * so we must remove it from the cache and re-enter it with the
635 * hash based on the new location of the directory entry.
637 if (dep->de_Attributes & ATTR_DIRECTORY)
639 msdosfs_hashrem(dep);
640 msdosfs_hashins(dep);
645 struct vop_reclaim_args /* {
649 struct vnode *vp = ap->a_vp;
650 struct denode *dep = VTODE(vp);
653 printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
654 dep, dep->de_Name, dep->de_refcnt);
657 if (prtactive && vp->v_usecount != 0)
658 vprint("msdosfs_reclaim(): pushing active", vp);
660 * Remove the denode from its hash chain.
662 msdosfs_hashrem(dep);
664 * Purge old data structures associated with the denode.
668 vrele(dep->de_devvp);
674 FREE(dep, M_MSDOSFSNODE);
682 struct vop_inactive_args /* {
687 struct vnode *vp = ap->a_vp;
688 struct denode *dep = VTODE(vp);
689 struct proc *p = ap->a_p;
693 printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
696 if (prtactive && vp->v_usecount != 0)
697 vprint("msdosfs_inactive(): pushing active", vp);
700 * Ignore denodes related to stale file handles.
702 if (dep->de_Name[0] == SLOT_DELETED)
706 * If the file has been deleted and it is on a read/write
707 * filesystem, then truncate the file, and mark the directory slot
708 * as empty. (This may not be necessary for the dos filesystem.)
711 printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n",
712 dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY);
714 if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
715 error = detrunc(dep, (u_long) 0, 0, NOCRED, p);
716 dep->de_flag |= DE_UPDATE;
717 dep->de_Name[0] = SLOT_DELETED;
722 VOP_UNLOCK(vp, 0, p);
724 * If we are done with the denode, reclaim it
725 * so that it can be reused immediately.
728 printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vp->v_usecount,
731 if (dep->de_Name[0] == SLOT_DELETED)
732 vrecycle(vp, (struct simplelock *)0, p);