xref: /netbsd-src/sys/fs/msdosfs/msdosfs_denode.c (revision 796c32c94f6e154afc9de0f63da35c91bb739b45)
1 /*	$NetBSD: msdosfs_denode.c,v 1.56 2017/05/26 14:34:19 riastradh Exp $	*/
2 
3 /*-
4  * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
5  * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
6  * All rights reserved.
7  * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *	This product includes software developed by TooLs GmbH.
20  * 4. The name of TooLs GmbH may not be used to endorse or promote products
21  *    derived from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
24  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
25  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
26  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
27  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
28  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
29  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
30  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
31  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
32  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
33  */
34 /*
35  * Written by Paul Popelka (paulp@uts.amdahl.com)
36  *
37  * You can do anything you want with this software, just don't say you wrote
38  * it, and don't remove this notice.
39  *
40  * This software is provided "as is".
41  *
42  * The author supplies this software to be publicly redistributed on the
43  * understanding that the author is not responsible for the correct
44  * functioning of this software in any circumstances and is not liable for
45  * any damages caused by this software.
46  *
47  * October 1992
48  */
49 
50 #include <sys/cdefs.h>
51 __KERNEL_RCSID(0, "$NetBSD: msdosfs_denode.c,v 1.56 2017/05/26 14:34:19 riastradh Exp $");
52 
53 #include <sys/param.h>
54 #include <sys/systm.h>
55 #include <sys/mount.h>
56 #include <sys/malloc.h>
57 #include <sys/pool.h>
58 #include <sys/proc.h>
59 #include <sys/buf.h>
60 #include <sys/vnode.h>
61 #include <sys/kernel.h>		/* defines "time" */
62 #include <sys/dirent.h>
63 #include <sys/namei.h>
64 #include <sys/kauth.h>
65 
66 #include <uvm/uvm_extern.h>
67 
68 #include <fs/msdosfs/bpb.h>
69 #include <fs/msdosfs/msdosfsmount.h>
70 #include <fs/msdosfs/direntry.h>
71 #include <fs/msdosfs/denode.h>
72 #include <fs/msdosfs/fat.h>
73 
74 struct pool msdosfs_denode_pool;
75 
76 struct fh_key {
77 	struct msdosfsmount *fhk_mount;
78 	uint32_t fhk_dircluster;
79 	uint32_t fhk_diroffset;
80 };
81 struct fh_node {
82 	struct rb_node fh_rbnode;
83 	struct fh_key fh_key;
84 #define fh_mount	fh_key.fhk_mount
85 #define fh_dircluster	fh_key.fhk_dircluster
86 #define fh_diroffset	fh_key.fhk_diroffset
87 	uint32_t fh_gen;
88 };
89 
90 static int
91 fh_compare_node_fh(void *ctx, const void *b, const void *key)
92 {
93 	const struct fh_node * const pnp = b;
94 	const struct fh_key * const fhp = key;
95 
96 	/* msdosfs_fh_destroy() below depends on first sorting on fh_mount. */
97 	if (pnp->fh_mount != fhp->fhk_mount)
98 		return (intptr_t)pnp->fh_mount - (intptr_t)fhp->fhk_mount;
99 	if (pnp->fh_dircluster != fhp->fhk_dircluster)
100 		return pnp->fh_dircluster - fhp->fhk_dircluster;
101 	return pnp->fh_diroffset - fhp->fhk_diroffset;
102 }
103 
104 static int
105 fh_compare_nodes(void *ctx, const void *parent, const void *node)
106 {
107 	const struct fh_node * const np = node;
108 
109 	return fh_compare_node_fh(ctx, parent, &np->fh_key);
110 }
111 
112 static uint32_t fh_generation;
113 static kmutex_t fh_lock;
114 static struct pool fh_pool;
115 static rb_tree_t fh_rbtree;
116 static const rb_tree_ops_t fh_rbtree_ops = {
117 	.rbto_compare_nodes = fh_compare_nodes,
118 	.rbto_compare_key = fh_compare_node_fh,
119 	.rbto_node_offset = offsetof(struct fh_node, fh_rbnode),
120 	.rbto_context = NULL
121 };
122 
123 static const struct genfs_ops msdosfs_genfsops = {
124 	.gop_size = genfs_size,
125 	.gop_alloc = msdosfs_gop_alloc,
126 	.gop_write = genfs_gop_write,
127 	.gop_markupdate = msdosfs_gop_markupdate,
128 };
129 
130 MALLOC_DECLARE(M_MSDOSFSFAT);
131 
132 void
133 msdosfs_init(void)
134 {
135 
136 	malloc_type_attach(M_MSDOSFSMNT);
137 	malloc_type_attach(M_MSDOSFSFAT);
138 	malloc_type_attach(M_MSDOSFSTMP);
139 	pool_init(&msdosfs_denode_pool, sizeof(struct denode), 0, 0, 0,
140 	    "msdosnopl", &pool_allocator_nointr, IPL_NONE);
141 	pool_init(&fh_pool, sizeof(struct fh_node), 0, 0, 0,
142 	    "msdosfhpl", &pool_allocator_nointr, IPL_NONE);
143 	rb_tree_init(&fh_rbtree, &fh_rbtree_ops);
144 	mutex_init(&fh_lock, MUTEX_DEFAULT, IPL_NONE);
145 }
146 
147 /*
148  * Reinitialize.
149  */
150 
151 void
152 msdosfs_reinit(void)
153 {
154 
155 }
156 
157 void
158 msdosfs_done(void)
159 {
160 	pool_destroy(&msdosfs_denode_pool);
161 	pool_destroy(&fh_pool);
162 	mutex_destroy(&fh_lock);
163 	malloc_type_detach(M_MSDOSFSTMP);
164 	malloc_type_detach(M_MSDOSFSFAT);
165 	malloc_type_detach(M_MSDOSFSMNT);
166 }
167 
168 /*
169  * If deget() succeeds it returns with the gotten denode unlocked.
170  *
171  * pmp	     - address of msdosfsmount structure of the filesystem containing
172  *	       the denode of interest.  The pm_dev field and the address of
173  *	       the msdosfsmount structure are used.
174  * dirclust  - which cluster bp contains, if dirclust is 0 (root directory)
175  *	       diroffset is relative to the beginning of the root directory,
176  *	       otherwise it is cluster relative.
177  * diroffset - offset past begin of cluster of denode we want
178  * vpp	     - returns the address of the gotten vnode.
179  */
180 int
181 deget(struct msdosfsmount *pmp, u_long dirclust, u_long diroffset,
182     struct vnode **vpp)
183 	/* pmp:	 so we know the maj/min number */
184 	/* dirclust:		 cluster this dir entry came from */
185 	/* diroffset:		 index of entry within the cluster */
186 	/* vpp:			 returns the addr of the gotten vnode */
187 {
188 	int error;
189 	struct denode_key key;
190 
191 	/*
192 	 * On FAT32 filesystems, root is a (more or less) normal
193 	 * directory
194 	 */
195 	if (FAT32(pmp) && dirclust == MSDOSFSROOT)
196 		dirclust = pmp->pm_rootdirblk;
197 
198 	memset(&key, 0, sizeof(key));
199 	key.dk_dirclust = dirclust;
200 	key.dk_diroffset = diroffset;
201 	/* key.dk_dirgen = NULL; */
202 
203 	error = vcache_get(pmp->pm_mountp, &key, sizeof(key), vpp);
204 	return error;
205 }
206 
207 int
208 msdosfs_loadvnode(struct mount *mp, struct vnode *vp,
209     const void *key, size_t key_len, const void **new_key)
210 {
211 	bool is_root;
212 	int error;
213 	extern int (**msdosfs_vnodeop_p)(void *);
214 	struct msdosfsmount *pmp;
215 	struct direntry *direntptr;
216 	struct denode *ldep;
217 	struct buf *bp;
218 	struct denode_key dkey;
219 
220 	KASSERT(key_len == sizeof(dkey));
221 	memcpy(&dkey, key, key_len);
222 	KASSERT(dkey.dk_dirgen == NULL);
223 
224 	pmp = VFSTOMSDOSFS(mp);
225 	is_root = ((dkey.dk_dirclust == MSDOSFSROOT ||
226 	    (FAT32(pmp) && dkey.dk_dirclust == pmp->pm_rootdirblk)) &&
227 	    dkey.dk_diroffset == MSDOSFSROOT_OFS);
228 
229 #ifdef MSDOSFS_DEBUG
230 	printf("loadvnode(pmp %p, dirclust %lu, diroffset %lx, vp %p)\n",
231 	    pmp, dkey.dk_dirclust, dkey.dk_diroffset, vp);
232 #endif
233 
234 	ldep = pool_get(&msdosfs_denode_pool, PR_WAITOK);
235 	memset(ldep, 0, sizeof *ldep);
236 	/* ldep->de_flag = 0; */
237 	/* ldep->de_devvp = 0; */
238 	/* ldep->de_lockf = 0; */
239 	ldep->de_dev = pmp->pm_dev;
240 	ldep->de_dirclust = dkey.dk_dirclust;
241 	ldep->de_diroffset = dkey.dk_diroffset;
242 	ldep->de_pmp = pmp;
243 	ldep->de_devvp = pmp->pm_devvp;
244 	ldep->de_refcnt = 1;
245 	fc_purge(ldep, 0);	/* init the FAT cache for this denode */
246 
247 	/*
248 	 * Copy the directory entry into the denode area of the vnode.
249 	 */
250 	if (is_root) {
251 		/*
252 		 * Directory entry for the root directory. There isn't one,
253 		 * so we manufacture one. We should probably rummage
254 		 * through the root directory and find a label entry (if it
255 		 * exists), and then use the time and date from that entry
256 		 * as the time and date for the root denode.
257 		 */
258 		ldep->de_Attributes = ATTR_DIRECTORY;
259 		if (FAT32(pmp))
260 			ldep->de_StartCluster = pmp->pm_rootdirblk;
261 			/* de_FileSize will be filled in further down */
262 		else {
263 			ldep->de_StartCluster = MSDOSFSROOT;
264 			ldep->de_FileSize = pmp->pm_rootdirsize *
265 			    pmp->pm_BytesPerSec;
266 		}
267 		/*
268 		 * fill in time and date so that dos2unixtime() doesn't
269 		 * spit up when called from msdosfs_getattr() with root
270 		 * denode
271 		 */
272 		ldep->de_CHun = 0;
273 		ldep->de_CTime = 0x0000;	/* 00:00:00	 */
274 		ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
275 		    | (1 << DD_DAY_SHIFT);
276 		/* Jan 1, 1980	 */
277 		ldep->de_ADate = ldep->de_CDate;
278 		ldep->de_MTime = ldep->de_CTime;
279 		ldep->de_MDate = ldep->de_CDate;
280 		/* leave the other fields as garbage */
281 	} else {
282 		error = readep(pmp, ldep->de_dirclust, ldep->de_diroffset,
283 		    &bp, &direntptr);
284 		if (error) {
285 			pool_put(&msdosfs_denode_pool, ldep);
286 			return error;
287 		}
288 		DE_INTERNALIZE(ldep, direntptr);
289 		brelse(bp, 0);
290 	}
291 
292 	/*
293 	 * Fill in a few fields of the vnode and finish filling in the
294 	 * denode.
295 	 */
296 	if (ldep->de_Attributes & ATTR_DIRECTORY) {
297 		/*
298 		 * Since DOS directory entries that describe directories
299 		 * have 0 in the filesize field, we take this opportunity
300 		 * to find out the length of the directory and plug it into
301 		 * the denode structure.
302 		 */
303 		u_long size;
304 
305 		vp->v_type = VDIR;
306 		if (ldep->de_StartCluster != MSDOSFSROOT) {
307 			error = pcbmap(ldep, CLUST_END, 0, &size, 0);
308 			if (error == E2BIG) {
309 				ldep->de_FileSize = de_cn2off(pmp, size);
310 				error = 0;
311 			} else
312 				printf("loadvnode(): pcbmap returned %d\n",
313 				    error);
314 		}
315 	} else
316 		vp->v_type = VREG;
317 	vref(ldep->de_devvp);
318 	if (is_root)
319 		vp->v_vflag |= VV_ROOT;
320 	vp->v_tag = VT_MSDOSFS;
321 	vp->v_op = msdosfs_vnodeop_p;
322 	vp->v_data = ldep;
323 	ldep->de_vnode = vp;
324 	genfs_node_init(vp, &msdosfs_genfsops);
325 	uvm_vnp_setsize(vp, ldep->de_FileSize);
326 	*new_key = &ldep->de_key;
327 
328 	return 0;
329 }
330 
331 int
332 deupdat(struct denode *dep, int waitfor)
333 {
334 
335 	return (msdosfs_update(DETOV(dep), NULL, NULL,
336 	    waitfor ? UPDATE_WAIT : 0));
337 }
338 
339 /*
340  * Truncate the file described by dep to the length specified by length.
341  */
342 int
343 detrunc(struct denode *dep, u_long length, int flags, kauth_cred_t cred)
344 {
345 	int error;
346 	int allerror;
347 	u_long eofentry;
348 	u_long chaintofree = 0;
349 	daddr_t bn, lastblock;
350 	int boff;
351 	int isadir = dep->de_Attributes & ATTR_DIRECTORY;
352 	struct buf *bp;
353 	struct msdosfsmount *pmp = dep->de_pmp;
354 
355 #ifdef MSDOSFS_DEBUG
356 	printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
357 #endif
358 
359 	/*
360 	 * Disallow attempts to truncate the root directory since it is of
361 	 * fixed size.  That's just the way dos filesystems are.  We use
362 	 * the VROOT bit in the vnode because checking for the directory
363 	 * bit and a startcluster of 0 in the denode is not adequate to
364 	 * recognize the root directory at this point in a file or
365 	 * directory's life.
366 	 */
367 	if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) {
368 		printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
369 		    dep->de_dirclust, dep->de_diroffset);
370 		return (EINVAL);
371 	}
372 
373 	uvm_vnp_setsize(DETOV(dep), length);
374 
375 	if (dep->de_FileSize < length)
376 		return (deextend(dep, length, cred));
377 	lastblock = de_clcount(pmp, length) - 1;
378 
379 	/*
380 	 * If the desired length is 0 then remember the starting cluster of
381 	 * the file and set the StartCluster field in the directory entry
382 	 * to 0.  If the desired length is not zero, then get the number of
383 	 * the last cluster in the shortened file.  Then get the number of
384 	 * the first cluster in the part of the file that is to be freed.
385 	 * Then set the next cluster pointer in the last cluster of the
386 	 * file to CLUST_EOFE.
387 	 */
388 	if (length == 0) {
389 		chaintofree = dep->de_StartCluster;
390 		dep->de_StartCluster = 0;
391 		eofentry = ~0;
392 	} else {
393 		error = pcbmap(dep, lastblock, 0, &eofentry, 0);
394 		if (error) {
395 #ifdef MSDOSFS_DEBUG
396 			printf("detrunc(): pcbmap fails %d\n", error);
397 #endif
398 			return (error);
399 		}
400 	}
401 
402 	/*
403 	 * If the new length is not a multiple of the cluster size then we
404 	 * must zero the tail end of the new last cluster in case it
405 	 * becomes part of the file again because of a seek.
406 	 */
407 	if ((boff = length & pmp->pm_crbomask) != 0) {
408 		if (isadir) {
409 			bn = cntobn(pmp, eofentry);
410 			error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn),
411 			    pmp->pm_bpcluster, B_MODIFY, &bp);
412 			if (error) {
413 #ifdef MSDOSFS_DEBUG
414 				printf("detrunc(): bread fails %d\n", error);
415 #endif
416 				return (error);
417 			}
418 			memset((char *)bp->b_data + boff, 0,
419 			    pmp->pm_bpcluster - boff);
420 			if (flags & IO_SYNC)
421 				bwrite(bp);
422 			else
423 				bdwrite(bp);
424 		} else {
425 			ubc_zerorange(&DETOV(dep)->v_uobj, length,
426 				      pmp->pm_bpcluster - boff,
427 				      UBC_UNMAP_FLAG(DETOV(dep)));
428 		}
429 	}
430 
431 	/*
432 	 * Write out the updated directory entry.  Even if the update fails
433 	 * we free the trailing clusters.
434 	 */
435 	dep->de_FileSize = length;
436 	if (!isadir)
437 		dep->de_flag |= DE_UPDATE|DE_MODIFIED;
438 	vtruncbuf(DETOV(dep), lastblock + 1, 0, 0);
439 	allerror = deupdat(dep, 1);
440 #ifdef MSDOSFS_DEBUG
441 	printf("detrunc(): allerror %d, eofentry %lu\n",
442 	       allerror, eofentry);
443 #endif
444 
445 	fc_purge(dep, lastblock + 1);
446 
447 	/*
448 	 * If we need to break the cluster chain for the file then do it
449 	 * now.
450 	 */
451 	if (eofentry != ~0) {
452 		error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
453 				 &chaintofree, CLUST_EOFE);
454 		if (error) {
455 #ifdef MSDOSFS_DEBUG
456 			printf("detrunc(): fatentry errors %d\n", error);
457 #endif
458 			return (error);
459 		}
460 		fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
461 			    eofentry);
462 	}
463 
464 	/*
465 	 * Now free the clusters removed from the file because of the
466 	 * truncation.
467 	 */
468 	if (chaintofree != 0 && !MSDOSFSEOF(chaintofree, pmp->pm_fatmask))
469 		freeclusterchain(pmp, chaintofree);
470 
471 	return (allerror);
472 }
473 
474 /*
475  * Extend the file described by dep to length specified by length.
476  */
477 int
478 deextend(struct denode *dep, u_long length, kauth_cred_t cred)
479 {
480 	struct msdosfsmount *pmp = dep->de_pmp;
481 	u_long count, osize;
482 	int error;
483 
484 	/*
485 	 * The root of a DOS filesystem cannot be extended.
486 	 */
487 	if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp))
488 		return (EINVAL);
489 
490 	/*
491 	 * Directories cannot be extended.
492 	 */
493 	if (dep->de_Attributes & ATTR_DIRECTORY)
494 		return (EISDIR);
495 
496 	if (length <= dep->de_FileSize)
497 		panic("deextend: file too large");
498 
499 	/*
500 	 * Compute the number of clusters to allocate.
501 	 */
502 	count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
503 	if (count > 0) {
504 		if (count > pmp->pm_freeclustercount)
505 			return (ENOSPC);
506 		error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
507 		if (error) {
508 			/* truncate the added clusters away again */
509 			(void) detrunc(dep, dep->de_FileSize, 0, cred);
510 			return (error);
511 		}
512 	}
513 
514 	/*
515 	 * Zero extend file range; ubc_zerorange() uses ubc_alloc() and a
516 	 * memset(); we set the write size so ubc won't read in file data that
517 	 * is zero'd later.
518 	 */
519 	osize = dep->de_FileSize;
520 	dep->de_FileSize = length;
521 	uvm_vnp_setwritesize(DETOV(dep), (voff_t)dep->de_FileSize);
522 	dep->de_flag |= DE_UPDATE|DE_MODIFIED;
523 	ubc_zerorange(&DETOV(dep)->v_uobj, (off_t)osize,
524 	    (size_t)(round_page(dep->de_FileSize) - osize),
525 	    UBC_UNMAP_FLAG(DETOV(dep)));
526 	uvm_vnp_setsize(DETOV(dep), (voff_t)dep->de_FileSize);
527 	return (deupdat(dep, 1));
528 }
529 
530 int
531 msdosfs_reclaim(void *v)
532 {
533 	struct vop_reclaim_v2_args /* {
534 		struct vnode *a_vp;
535 	} */ *ap = v;
536 	struct vnode *vp = ap->a_vp;
537 	struct denode *dep = VTODE(vp);
538 
539 	VOP_UNLOCK(vp);
540 
541 #ifdef MSDOSFS_DEBUG
542 	printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
543 	    dep, dep->de_Name, dep->de_refcnt);
544 #endif
545 
546 	/*
547 	 * Purge old data structures associated with the denode.
548 	 */
549 	if (dep->de_devvp) {
550 		vrele(dep->de_devvp);
551 		dep->de_devvp = 0;
552 	}
553 #if 0 /* XXX */
554 	dep->de_flag = 0;
555 #endif
556 	/*
557 	 * To interlock with msdosfs_sync().
558 	 */
559 	genfs_node_destroy(vp);
560 	mutex_enter(vp->v_interlock);
561 	vp->v_data = NULL;
562 	mutex_exit(vp->v_interlock);
563 	pool_put(&msdosfs_denode_pool, dep);
564 	return (0);
565 }
566 
567 int
568 msdosfs_inactive(void *v)
569 {
570 	struct vop_inactive_v2_args /* {
571 		struct vnode *a_vp;
572 		bool *a_recycle;
573 	} */ *ap = v;
574 	struct vnode *vp = ap->a_vp;
575 	struct denode *dep = VTODE(vp);
576 	int error = 0;
577 
578 #ifdef MSDOSFS_DEBUG
579 	printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
580 #endif
581 
582 	/*
583 	 * Get rid of denodes related to stale file handles.
584 	 */
585 	if (dep->de_Name[0] == SLOT_DELETED)
586 		goto out;
587 
588 	/*
589 	 * If the file has been deleted and it is on a read/write
590 	 * filesystem, then truncate the file, and mark the directory slot
591 	 * as empty.  (This may not be necessary for the dos filesystem.)
592 	 */
593 #ifdef MSDOSFS_DEBUG
594 	printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x %s\n",
595 	       dep, dep->de_refcnt, vp->v_mount->mnt_flag,
596 		(vp->v_mount->mnt_flag & MNT_RDONLY) ? "MNT_RDONLY" : "");
597 #endif
598 	if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
599 		if (dep->de_FileSize != 0) {
600 			error = detrunc(dep, (u_long)0, 0, NOCRED);
601 		}
602 		dep->de_Name[0] = SLOT_DELETED;
603 		msdosfs_fh_remove(dep->de_pmp,
604 		    dep->de_dirclust, dep->de_diroffset);
605 	}
606 	deupdat(dep, 0);
607 out:
608 	/*
609 	 * If we are done with the denode, reclaim it
610 	 * so that it can be reused immediately.
611 	 */
612 #ifdef MSDOSFS_DEBUG
613 	printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n",
614 		vp->v_usecount, dep->de_Name[0]);
615 #endif
616 	*ap->a_recycle = (dep->de_Name[0] == SLOT_DELETED);
617 
618 	return (error);
619 }
620 
621 int
622 msdosfs_gop_alloc(struct vnode *vp, off_t off,
623     off_t len, int flags, kauth_cred_t cred)
624 {
625 	return 0;
626 }
627 
628 void
629 msdosfs_gop_markupdate(struct vnode *vp, int flags)
630 {
631 	u_long mask = 0;
632 
633 	if ((flags & GOP_UPDATE_ACCESSED) != 0) {
634 		mask = DE_ACCESS;
635 	}
636 	if ((flags & GOP_UPDATE_MODIFIED) != 0) {
637 		mask |= DE_UPDATE;
638 	}
639 	if (mask) {
640 		struct denode *dep = VTODE(vp);
641 
642 		dep->de_flag |= mask;
643 	}
644 }
645 
646 int
647 msdosfs_fh_enter(struct msdosfsmount *pmp,
648      uint32_t dircluster, uint32_t diroffset, uint32_t *genp)
649 {
650 	struct fh_key fhkey;
651 	struct fh_node *fhp;
652 
653 	fhkey.fhk_mount = pmp;
654 	fhkey.fhk_dircluster = dircluster;
655 	fhkey.fhk_diroffset = diroffset;
656 
657 	mutex_enter(&fh_lock);
658 	fhp = rb_tree_find_node(&fh_rbtree, &fhkey);
659 	if (fhp == NULL) {
660 		mutex_exit(&fh_lock);
661 		fhp = pool_get(&fh_pool, PR_WAITOK);
662 		mutex_enter(&fh_lock);
663 		fhp->fh_key = fhkey;
664 		fhp->fh_gen = fh_generation++;
665 		rb_tree_insert_node(&fh_rbtree, fhp);
666 	}
667 	*genp = fhp->fh_gen;
668 	mutex_exit(&fh_lock);
669 	return 0;
670 }
671 
672 int
673 msdosfs_fh_remove(struct msdosfsmount *pmp,
674      uint32_t dircluster, uint32_t diroffset)
675 {
676 	struct fh_key fhkey;
677 	struct fh_node *fhp;
678 
679 	fhkey.fhk_mount = pmp;
680 	fhkey.fhk_dircluster = dircluster;
681 	fhkey.fhk_diroffset = diroffset;
682 
683 	mutex_enter(&fh_lock);
684 	fhp = rb_tree_find_node(&fh_rbtree, &fhkey);
685 	if (fhp == NULL) {
686 		mutex_exit(&fh_lock);
687 		return ENOENT;
688 	}
689 	rb_tree_remove_node(&fh_rbtree, fhp);
690 	mutex_exit(&fh_lock);
691 	pool_put(&fh_pool, fhp);
692 	return 0;
693 }
694 
695 int
696 msdosfs_fh_lookup(struct msdosfsmount *pmp,
697      uint32_t dircluster, uint32_t diroffset, uint32_t *genp)
698 {
699 	struct fh_key fhkey;
700 	struct fh_node *fhp;
701 
702 	fhkey.fhk_mount = pmp;
703 	fhkey.fhk_dircluster = dircluster;
704 	fhkey.fhk_diroffset = diroffset;
705 
706 	mutex_enter(&fh_lock);
707 	fhp = rb_tree_find_node(&fh_rbtree, &fhkey);
708 	if (fhp == NULL) {
709 		mutex_exit(&fh_lock);
710 		return ESTALE;
711 	}
712 	*genp = fhp->fh_gen;
713 	mutex_exit(&fh_lock);
714 	return 0;
715 }
716 
717 void
718 msdosfs_fh_destroy(struct msdosfsmount *pmp)
719 {
720 	struct fh_key fhkey;
721 	struct fh_node *fhp, *nfhp;
722 
723 	fhkey.fhk_mount = pmp;
724 	fhkey.fhk_dircluster = 0;
725 	fhkey.fhk_diroffset = 0;
726 
727 	mutex_enter(&fh_lock);
728 	for (fhp = rb_tree_find_node_geq(&fh_rbtree, &fhkey);
729 	    fhp != NULL && fhp->fh_mount == pmp; fhp = nfhp) {
730 		nfhp = rb_tree_iterate(&fh_rbtree, fhp, RB_DIR_RIGHT);
731 		rb_tree_remove_node(&fh_rbtree, fhp);
732 		pool_put(&fh_pool, fhp);
733 	}
734 #ifdef DIAGNOSTIC
735 	RB_TREE_FOREACH(fhp, &fh_rbtree) {
736 		KASSERT(fhp->fh_mount != pmp);
737 	}
738 #endif
739 	mutex_exit(&fh_lock);
740 }
741