xref: /netbsd-src/sys/fs/msdosfs/msdosfs_vnops.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /*	$NetBSD: msdosfs_vnops.c,v 1.89 2014/01/23 10:13:56 hannken 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_vnops.c,v 1.89 2014/01/23 10:13:56 hannken Exp $");
52 
53 #include <sys/param.h>
54 #include <sys/systm.h>
55 #include <sys/namei.h>
56 #include <sys/resourcevar.h>	/* defines plimit structure in proc struct */
57 #include <sys/kernel.h>
58 #include <sys/file.h>		/* define FWRITE ... */
59 #include <sys/stat.h>
60 #include <sys/buf.h>
61 #include <sys/proc.h>
62 #include <sys/mount.h>
63 #include <sys/fstrans.h>
64 #include <sys/vnode.h>
65 #include <sys/signalvar.h>
66 #include <sys/malloc.h>
67 #include <sys/dirent.h>
68 #include <sys/lockf.h>
69 #include <sys/kauth.h>
70 
71 #include <miscfs/genfs/genfs.h>
72 #include <miscfs/specfs/specdev.h> /* XXX */	/* defines v_rdev */
73 
74 #include <uvm/uvm_extern.h>
75 
76 #include <fs/msdosfs/bpb.h>
77 #include <fs/msdosfs/direntry.h>
78 #include <fs/msdosfs/denode.h>
79 #include <fs/msdosfs/msdosfsmount.h>
80 #include <fs/msdosfs/fat.h>
81 
82 /*
83  * Some general notes:
84  *
85  * In the ufs filesystem the inodes, superblocks, and indirect blocks are
86  * read/written using the vnode for the filesystem. Blocks that represent
87  * the contents of a file are read/written using the vnode for the file
88  * (including directories when they are read/written as files). This
89  * presents problems for the dos filesystem because data that should be in
90  * an inode (if dos had them) resides in the directory itself.  Since we
91  * must update directory entries without the benefit of having the vnode
92  * for the directory we must use the vnode for the filesystem.  This means
93  * that when a directory is actually read/written (via read, write, or
94  * readdir, or seek) we must use the vnode for the filesystem instead of
95  * the vnode for the directory as would happen in ufs. This is to insure we
96  * retrieve the correct block from the buffer cache since the hash value is
97  * based upon the vnode address and the desired block number.
98  */
99 
100 /*
101  * Create a regular file. On entry the directory to contain the file being
102  * created is locked.  We must release before we return.
103  */
104 int
105 msdosfs_create(void *v)
106 {
107 	struct vop_create_v3_args /* {
108 		struct vnode *a_dvp;
109 		struct vnode **a_vpp;
110 		struct componentname *a_cnp;
111 		struct vattr *a_vap;
112 	} */ *ap = v;
113 	struct componentname *cnp = ap->a_cnp;
114 	struct denode ndirent;
115 	struct denode *dep;
116 	struct denode *pdep = VTODE(ap->a_dvp);
117 	int error;
118 
119 #ifdef MSDOSFS_DEBUG
120 	printf("msdosfs_create(cnp %p, vap %p\n", cnp, ap->a_vap);
121 #endif
122 
123 	fstrans_start(ap->a_dvp->v_mount, FSTRANS_SHARED);
124 	/*
125 	 * If this is the root directory and there is no space left we
126 	 * can't do anything.  This is because the root directory can not
127 	 * change size.
128 	 */
129 	if (pdep->de_StartCluster == MSDOSFSROOT
130 	    && pdep->de_fndoffset >= pdep->de_FileSize) {
131 		error = ENOSPC;
132 		goto bad;
133 	}
134 
135 	/*
136 	 * Create a directory entry for the file, then call createde() to
137 	 * have it installed. NOTE: DOS files are always executable.  We
138 	 * use the absence of the owner write bit to make the file
139 	 * readonly.
140 	 */
141 	memset(&ndirent, 0, sizeof(ndirent));
142 	if ((error = uniqdosname(pdep, cnp, ndirent.de_Name)) != 0)
143 		goto bad;
144 
145 	ndirent.de_Attributes = (ap->a_vap->va_mode & S_IWUSR) ?
146 				ATTR_ARCHIVE : ATTR_ARCHIVE | ATTR_READONLY;
147 	ndirent.de_StartCluster = 0;
148 	ndirent.de_FileSize = 0;
149 	ndirent.de_dev = pdep->de_dev;
150 	ndirent.de_devvp = pdep->de_devvp;
151 	ndirent.de_pmp = pdep->de_pmp;
152 	ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE;
153 	DETIMES(&ndirent, NULL, NULL, NULL, pdep->de_pmp->pm_gmtoff);
154 	if ((error = createde(&ndirent, pdep, &dep, cnp)) != 0)
155 		goto bad;
156 	fstrans_done(ap->a_dvp->v_mount);
157 	VN_KNOTE(ap->a_dvp, NOTE_WRITE);
158 	*ap->a_vpp = DETOV(dep);
159 	return (0);
160 
161 bad:
162 	fstrans_done(ap->a_dvp->v_mount);
163 	return (error);
164 }
165 
166 int
167 msdosfs_close(void *v)
168 {
169 	struct vop_close_args /* {
170 		struct vnode *a_vp;
171 		int a_fflag;
172 		kauth_cred_t a_cred;
173 	} */ *ap = v;
174 	struct vnode *vp = ap->a_vp;
175 	struct denode *dep = VTODE(vp);
176 
177 	fstrans_start(vp->v_mount, FSTRANS_SHARED);
178 	mutex_enter(vp->v_interlock);
179 	if (vp->v_usecount > 1)
180 		DETIMES(dep, NULL, NULL, NULL, dep->de_pmp->pm_gmtoff);
181 	mutex_exit(vp->v_interlock);
182 	fstrans_done(vp->v_mount);
183 	return (0);
184 }
185 
186 static int
187 msdosfs_check_possible(struct vnode *vp, struct denode *dep, mode_t mode)
188 {
189 
190 	/*
191 	 * Disallow write attempts on read-only file systems;
192 	 * unless the file is a socket, fifo, or a block or
193 	 * character device resident on the file system.
194 	 */
195 	if (mode & VWRITE) {
196 		switch (vp->v_type) {
197 		case VDIR:
198 		case VLNK:
199 		case VREG:
200 			if (vp->v_mount->mnt_flag & MNT_RDONLY)
201 				return (EROFS);
202 		default:
203 			break;
204 		}
205 	}
206 
207 	return 0;
208 }
209 
210 static int
211 msdosfs_check_permitted(struct vnode *vp, struct denode *dep, mode_t mode,
212     kauth_cred_t cred)
213 {
214 	struct msdosfsmount *pmp = dep->de_pmp;
215 	mode_t file_mode;
216 
217 	if ((dep->de_Attributes & ATTR_READONLY) == 0)
218 		file_mode = S_IRWXU|S_IRWXG|S_IRWXO;
219 	else
220 		file_mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
221 
222 	file_mode &= (vp->v_type == VDIR ? pmp->pm_dirmask : pmp->pm_mask);
223 
224 	return kauth_authorize_vnode(cred, KAUTH_ACCESS_ACTION(mode,
225 	    vp->v_type, file_mode), vp, NULL, genfs_can_access(vp->v_type,
226 	    file_mode, pmp->pm_uid, pmp->pm_gid, mode, cred));
227 }
228 
229 int
230 msdosfs_access(void *v)
231 {
232 	struct vop_access_args /* {
233 		struct vnode *a_vp;
234 		int a_mode;
235 		kauth_cred_t a_cred;
236 	} */ *ap = v;
237 	struct vnode *vp = ap->a_vp;
238 	struct denode *dep = VTODE(vp);
239 	int error;
240 
241 	error = msdosfs_check_possible(vp, dep, ap->a_mode);
242 	if (error)
243 		return error;
244 
245 	error = msdosfs_check_permitted(vp, dep, ap->a_mode, ap->a_cred);
246 
247 	return error;
248 }
249 
250 int
251 msdosfs_getattr(void *v)
252 {
253 	struct vop_getattr_args /* {
254 		struct vnode *a_vp;
255 		struct vattr *a_vap;
256 		kauth_cred_t a_cred;
257 	} */ *ap = v;
258 	struct denode *dep = VTODE(ap->a_vp);
259 	struct msdosfsmount *pmp = dep->de_pmp;
260 	struct vattr *vap = ap->a_vap;
261 	mode_t mode;
262 	u_long dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry);
263 	ino_t fileid;
264 
265 	fstrans_start(ap->a_vp->v_mount, FSTRANS_SHARED);
266 	DETIMES(dep, NULL, NULL, NULL, pmp->pm_gmtoff);
267 	vap->va_fsid = dep->de_dev;
268 	/*
269 	 * The following computation of the fileid must be the same as that
270 	 * used in msdosfs_readdir() to compute d_fileno. If not, pwd
271 	 * doesn't work.
272 	 */
273 	if (dep->de_Attributes & ATTR_DIRECTORY) {
274 		fileid = cntobn(pmp, (ino_t)dep->de_StartCluster) * dirsperblk;
275 		if (dep->de_StartCluster == MSDOSFSROOT)
276 			fileid = 1;
277 	} else {
278 		fileid = cntobn(pmp, (ino_t)dep->de_dirclust) * dirsperblk;
279 		if (dep->de_dirclust == MSDOSFSROOT)
280 			fileid = roottobn(pmp, 0) * dirsperblk;
281 		fileid += dep->de_diroffset / sizeof(struct direntry);
282 	}
283 	vap->va_fileid = fileid;
284 	if ((dep->de_Attributes & ATTR_READONLY) == 0)
285 		mode = S_IRWXU|S_IRWXG|S_IRWXO;
286 	else
287 		mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
288 	vap->va_mode =
289 	    mode & (ap->a_vp->v_type == VDIR ? pmp->pm_dirmask : pmp->pm_mask);
290 	vap->va_uid = pmp->pm_uid;
291 	vap->va_gid = pmp->pm_gid;
292 	vap->va_nlink = 1;
293 	vap->va_rdev = 0;
294 	vap->va_size = ap->a_vp->v_size;
295 	dos2unixtime(dep->de_MDate, dep->de_MTime, 0, pmp->pm_gmtoff,
296 	    &vap->va_mtime);
297 	if (dep->de_pmp->pm_flags & MSDOSFSMNT_LONGNAME) {
298 		dos2unixtime(dep->de_ADate, 0, 0, pmp->pm_gmtoff,
299 		    &vap->va_atime);
300 		dos2unixtime(dep->de_CDate, dep->de_CTime, dep->de_CHun,
301 		    pmp->pm_gmtoff, &vap->va_ctime);
302 	} else {
303 		vap->va_atime = vap->va_mtime;
304 		vap->va_ctime = vap->va_mtime;
305 	}
306 	vap->va_flags = 0;
307 	if ((dep->de_Attributes & ATTR_ARCHIVE) == 0) {
308 		vap->va_flags |= SF_ARCHIVED;
309 		vap->va_mode  |= S_ARCH1;
310 	}
311 	vap->va_gen = 0;
312 	vap->va_blocksize = pmp->pm_bpcluster;
313 	vap->va_bytes =
314 	    (dep->de_FileSize + pmp->pm_crbomask) & ~pmp->pm_crbomask;
315 	vap->va_type = ap->a_vp->v_type;
316 	fstrans_done(ap->a_vp->v_mount);
317 	return (0);
318 }
319 
320 int
321 msdosfs_setattr(void *v)
322 {
323 	struct vop_setattr_args /* {
324 		struct vnode *a_vp;
325 		struct vattr *a_vap;
326 		kauth_cred_t a_cred;
327 	} */ *ap = v;
328 	int error = 0, de_changed = 0;
329 	struct denode *dep = VTODE(ap->a_vp);
330 	struct msdosfsmount *pmp = dep->de_pmp;
331 	struct vnode *vp  = ap->a_vp;
332 	struct vattr *vap = ap->a_vap;
333 	kauth_cred_t cred = ap->a_cred;
334 
335 #ifdef MSDOSFS_DEBUG
336 	printf("msdosfs_setattr(): vp %p, vap %p, cred %p\n",
337 	    ap->a_vp, vap, cred);
338 #endif
339 	/*
340 	 * Note we silently ignore uid or gid changes.
341 	 */
342 	if ((vap->va_type != VNON) || (vap->va_nlink != (nlink_t)VNOVAL) ||
343 	    (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
344 	    (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
345 	    (vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL) ||
346 	    (vap->va_uid != VNOVAL && vap->va_uid != pmp->pm_uid) ||
347 	    (vap->va_gid != VNOVAL && vap->va_gid != pmp->pm_gid)) {
348 #ifdef MSDOSFS_DEBUG
349 		printf("msdosfs_setattr(): returning EINVAL\n");
350 		printf("    va_type %d, va_nlink %x, va_fsid %"PRIx64", va_fileid %llx\n",
351 		    vap->va_type, vap->va_nlink, vap->va_fsid,
352 		    (unsigned long long)vap->va_fileid);
353 		printf("    va_blocksize %lx, va_rdev %"PRIx64", va_bytes %"PRIx64", va_gen %lx\n",
354 		    vap->va_blocksize, vap->va_rdev, vap->va_bytes, vap->va_gen);
355 #endif
356 		return (EINVAL);
357 	}
358 	/*
359 	 * Silently ignore attributes modifications on directories.
360 	 */
361 	if (ap->a_vp->v_type == VDIR)
362 		return 0;
363 
364 	fstrans_start(vp->v_mount, FSTRANS_SHARED);
365 	if (vap->va_size != VNOVAL) {
366 		if (vp->v_mount->mnt_flag & MNT_RDONLY) {
367 			error = EROFS;
368 			goto bad;
369 		}
370 		error = detrunc(dep, (u_long)vap->va_size, 0, cred);
371 		if (error)
372 			goto bad;
373 		de_changed = 1;
374 	}
375 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
376 		if (vp->v_mount->mnt_flag & MNT_RDONLY) {
377 			error = EROFS;
378 			goto bad;
379 		}
380 		error = kauth_authorize_vnode(cred, KAUTH_VNODE_WRITE_TIMES,
381 		    ap->a_vp, NULL, genfs_can_chtimes(ap->a_vp, vap->va_vaflags,
382 		    pmp->pm_uid, cred));
383 		if (error)
384 			goto bad;
385 		if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95) == 0 &&
386 		    vap->va_atime.tv_sec != VNOVAL)
387 			unix2dostime(&vap->va_atime, pmp->pm_gmtoff, &dep->de_ADate, NULL, NULL);
388 		if (vap->va_mtime.tv_sec != VNOVAL)
389 			unix2dostime(&vap->va_mtime, pmp->pm_gmtoff, &dep->de_MDate, &dep->de_MTime, NULL);
390 		dep->de_Attributes |= ATTR_ARCHIVE;
391 		dep->de_flag |= DE_MODIFIED;
392 		de_changed = 1;
393 	}
394 	/*
395 	 * DOS files only have the ability to have their writability
396 	 * attribute set, so we use the owner write bit to set the readonly
397 	 * attribute.
398 	 */
399 	if (vap->va_mode != (mode_t)VNOVAL) {
400 		if (vp->v_mount->mnt_flag & MNT_RDONLY) {
401 			error = EROFS;
402 			goto bad;
403 		}
404 		error = kauth_authorize_vnode(cred, KAUTH_VNODE_WRITE_FLAGS, vp,
405 		    NULL, genfs_can_chflags(cred, vp->v_type, pmp->pm_uid, false));
406 		if (error)
407 			goto bad;
408 		/* We ignore the read and execute bits. */
409 		if (vap->va_mode & S_IWUSR)
410 			dep->de_Attributes &= ~ATTR_READONLY;
411 		else
412 			dep->de_Attributes |= ATTR_READONLY;
413 		dep->de_flag |= DE_MODIFIED;
414 		de_changed = 1;
415 	}
416 	/*
417 	 * Allow the `archived' bit to be toggled.
418 	 */
419 	if (vap->va_flags != VNOVAL) {
420 		if (vp->v_mount->mnt_flag & MNT_RDONLY) {
421 			error = EROFS;
422 			goto bad;
423 		}
424 		error = kauth_authorize_vnode(cred, KAUTH_VNODE_WRITE_FLAGS, vp,
425 		    NULL, genfs_can_chflags(cred, vp->v_type, pmp->pm_uid, false));
426 		if (error)
427 			goto bad;
428 		if (vap->va_flags & SF_ARCHIVED)
429 			dep->de_Attributes &= ~ATTR_ARCHIVE;
430 		else
431 			dep->de_Attributes |= ATTR_ARCHIVE;
432 		dep->de_flag |= DE_MODIFIED;
433 		de_changed = 1;
434 	}
435 
436 	if (de_changed) {
437 		VN_KNOTE(vp, NOTE_ATTRIB);
438 		error = deupdat(dep, 1);
439 		if (error)
440 			goto bad;
441 	}
442 
443 bad:
444 	fstrans_done(vp->v_mount);
445 	return error;
446 }
447 
448 int
449 msdosfs_read(void *v)
450 {
451 	struct vop_read_args /* {
452 		struct vnode *a_vp;
453 		struct uio *a_uio;
454 		int a_ioflag;
455 		kauth_cred_t a_cred;
456 	} */ *ap = v;
457 	int error = 0;
458 	int64_t diff;
459 	int blsize;
460 	long n;
461 	long on;
462 	daddr_t lbn;
463 	vsize_t bytelen;
464 	struct buf *bp;
465 	struct vnode *vp = ap->a_vp;
466 	struct denode *dep = VTODE(vp);
467 	struct msdosfsmount *pmp = dep->de_pmp;
468 	struct uio *uio = ap->a_uio;
469 
470 	/*
471 	 * If they didn't ask for any data, then we are done.
472 	 */
473 
474 	if (uio->uio_resid == 0)
475 		return (0);
476 	if (uio->uio_offset < 0)
477 		return (EINVAL);
478 	if (uio->uio_offset >= dep->de_FileSize)
479 		return (0);
480 
481 	fstrans_start(vp->v_mount, FSTRANS_SHARED);
482 	if (vp->v_type == VREG) {
483 		const int advice = IO_ADV_DECODE(ap->a_ioflag);
484 
485 		while (uio->uio_resid > 0) {
486 			bytelen = MIN(dep->de_FileSize - uio->uio_offset,
487 				      uio->uio_resid);
488 
489 			if (bytelen == 0)
490 				break;
491 			error = ubc_uiomove(&vp->v_uobj, uio, bytelen, advice,
492 			    UBC_READ | UBC_PARTIALOK | UBC_UNMAP_FLAG(vp));
493 			if (error)
494 				break;
495 		}
496 		dep->de_flag |= DE_ACCESS;
497 		goto out;
498 	}
499 
500 	/* this loop is only for directories now */
501 	do {
502 		lbn = de_cluster(pmp, uio->uio_offset);
503 		on = uio->uio_offset & pmp->pm_crbomask;
504 		n = MIN(pmp->pm_bpcluster - on, uio->uio_resid);
505 		if (uio->uio_offset >= dep->de_FileSize) {
506 			fstrans_done(vp->v_mount);
507 			return (0);
508 		}
509 		/* file size (and hence diff) may be up to 4GB */
510 		diff = dep->de_FileSize - uio->uio_offset;
511 		if (diff < n)
512 			n = (long) diff;
513 
514 		/* convert cluster # to sector # */
515 		error = pcbmap(dep, lbn, &lbn, 0, &blsize);
516 		if (error)
517 			goto bad;
518 
519 		/*
520 		 * If we are operating on a directory file then be sure to
521 		 * do i/o with the vnode for the filesystem instead of the
522 		 * vnode for the directory.
523 		 */
524 		error = bread(pmp->pm_devvp, de_bn2kb(pmp, lbn), blsize,
525 		    NOCRED, 0, &bp);
526 		if (error) {
527 			goto bad;
528 		}
529 		n = MIN(n, pmp->pm_bpcluster - bp->b_resid);
530 		error = uiomove((char *)bp->b_data + on, (int) n, uio);
531 		brelse(bp, 0);
532 	} while (error == 0 && uio->uio_resid > 0 && n != 0);
533 
534 out:
535 	if ((ap->a_ioflag & IO_SYNC) == IO_SYNC)
536 		error = deupdat(dep, 1);
537 bad:
538 	fstrans_done(vp->v_mount);
539 	return (error);
540 }
541 
542 /*
543  * Write data to a file or directory.
544  */
545 int
546 msdosfs_write(void *v)
547 {
548 	struct vop_write_args /* {
549 		struct vnode *a_vp;
550 		struct uio *a_uio;
551 		int a_ioflag;
552 		kauth_cred_t a_cred;
553 	} */ *ap = v;
554 	int resid, extended = 0;
555 	int error = 0;
556 	int ioflag = ap->a_ioflag;
557 	u_long osize;
558 	u_long count;
559 	vsize_t bytelen;
560 	off_t oldoff;
561 	size_t rem;
562 	struct uio *uio = ap->a_uio;
563 	struct vnode *vp = ap->a_vp;
564 	struct denode *dep = VTODE(vp);
565 	struct msdosfsmount *pmp = dep->de_pmp;
566 	kauth_cred_t cred = ap->a_cred;
567 	bool async;
568 
569 #ifdef MSDOSFS_DEBUG
570 	printf("msdosfs_write(vp %p, uio %p, ioflag %x, cred %p\n",
571 	    vp, uio, ioflag, cred);
572 	printf("msdosfs_write(): diroff %lu, dirclust %lu, startcluster %lu\n",
573 	    dep->de_diroffset, dep->de_dirclust, dep->de_StartCluster);
574 #endif
575 
576 	switch (vp->v_type) {
577 	case VREG:
578 		if (ioflag & IO_APPEND)
579 			uio->uio_offset = dep->de_FileSize;
580 		break;
581 	case VDIR:
582 		return EISDIR;
583 	default:
584 		panic("msdosfs_write(): bad file type");
585 	}
586 
587 	if (uio->uio_offset < 0)
588 		return (EINVAL);
589 
590 	if (uio->uio_resid == 0)
591 		return (0);
592 
593 	/* Don't bother to try to write files larger than the fs limit */
594 	if (uio->uio_offset + uio->uio_resid > MSDOSFS_FILESIZE_MAX)
595 		return (EFBIG);
596 
597 	fstrans_start(vp->v_mount, FSTRANS_SHARED);
598 	/*
599 	 * If the offset we are starting the write at is beyond the end of
600 	 * the file, then they've done a seek.  Unix filesystems allow
601 	 * files with holes in them, DOS doesn't so we must fill the hole
602 	 * with zeroed blocks.
603 	 */
604 	if (uio->uio_offset > dep->de_FileSize) {
605 		if ((error = deextend(dep, uio->uio_offset, cred)) != 0) {
606 			fstrans_done(vp->v_mount);
607 			return (error);
608 		}
609 	}
610 
611 	/*
612 	 * Remember some values in case the write fails.
613 	 */
614 	async = vp->v_mount->mnt_flag & MNT_ASYNC;
615 	resid = uio->uio_resid;
616 	osize = dep->de_FileSize;
617 
618 	/*
619 	 * If we write beyond the end of the file, extend it to its ultimate
620 	 * size ahead of the time to hopefully get a contiguous area.
621 	 */
622 	if (uio->uio_offset + resid > osize) {
623 		count = de_clcount(pmp, uio->uio_offset + resid) -
624 			de_clcount(pmp, osize);
625 		if ((error = extendfile(dep, count, NULL, NULL, 0)))
626 			goto errexit;
627 
628 		dep->de_FileSize = uio->uio_offset + resid;
629 		/* hint uvm to not read in extended part */
630 		uvm_vnp_setwritesize(vp, dep->de_FileSize);
631 		/* zero out the remainder of the last page */
632 		rem = round_page(dep->de_FileSize) - dep->de_FileSize;
633 		if (rem > 0)
634 			ubc_zerorange(&vp->v_uobj, (off_t)dep->de_FileSize,
635 			    rem, UBC_UNMAP_FLAG(vp));
636 		extended = 1;
637 	}
638 
639 	do {
640 		oldoff = uio->uio_offset;
641 		bytelen = uio->uio_resid;
642 
643 		error = ubc_uiomove(&vp->v_uobj, uio, bytelen,
644 		    IO_ADV_DECODE(ioflag), UBC_WRITE | UBC_UNMAP_FLAG(vp));
645 		if (error)
646 			break;
647 
648 		/*
649 		 * flush what we just wrote if necessary.
650 		 * XXXUBC simplistic async flushing.
651 		 */
652 
653 		if (!async && oldoff >> 16 != uio->uio_offset >> 16) {
654 			mutex_enter(vp->v_interlock);
655 			error = VOP_PUTPAGES(vp, (oldoff >> 16) << 16,
656 			    (uio->uio_offset >> 16) << 16,
657 			    PGO_CLEANIT | PGO_LAZY);
658 		}
659 	} while (error == 0 && uio->uio_resid > 0);
660 
661 	/* set final size */
662 	uvm_vnp_setsize(vp, dep->de_FileSize);
663 	if (error == 0 && ioflag & IO_SYNC) {
664 		mutex_enter(vp->v_interlock);
665 		error = VOP_PUTPAGES(vp, trunc_page(oldoff),
666 		    round_page(oldoff + bytelen), PGO_CLEANIT | PGO_SYNCIO);
667 	}
668 	dep->de_flag |= DE_UPDATE;
669 
670 	/*
671 	 * If the write failed and they want us to, truncate the file back
672 	 * to the size it was before the write was attempted.
673 	 */
674 errexit:
675 	if (resid > uio->uio_resid)
676 		VN_KNOTE(vp, NOTE_WRITE | (extended ? NOTE_EXTEND : 0));
677 	if (error) {
678 		detrunc(dep, osize, ioflag & IO_SYNC, NOCRED);
679 		uio->uio_offset -= resid - uio->uio_resid;
680 		uio->uio_resid = resid;
681 	} else if ((ioflag & IO_SYNC) == IO_SYNC)
682 		error = deupdat(dep, 1);
683 	fstrans_done(vp->v_mount);
684 	KASSERT(vp->v_size == dep->de_FileSize);
685 	return (error);
686 }
687 
688 int
689 msdosfs_update(struct vnode *vp, const struct timespec *acc,
690     const struct timespec *mod, int flags)
691 {
692 	struct buf *bp;
693 	struct direntry *dirp;
694 	struct denode *dep;
695 	int error;
696 
697 	if (vp->v_mount->mnt_flag & MNT_RDONLY)
698 		return (0);
699 	dep = VTODE(vp);
700 	DETIMES(dep, acc, mod, NULL, dep->de_pmp->pm_gmtoff);
701 	if ((dep->de_flag & DE_MODIFIED) == 0)
702 		return (0);
703 	dep->de_flag &= ~DE_MODIFIED;
704 	if (dep->de_Attributes & ATTR_DIRECTORY)
705 		return (0);
706 	if (dep->de_refcnt <= 0)
707 		return (0);
708 	error = readde(dep, &bp, &dirp);
709 	if (error)
710 		return (error);
711 	DE_EXTERNALIZE(dirp, dep);
712 	if (flags & (UPDATE_WAIT|UPDATE_DIROP))
713 		return (bwrite(bp));
714 	else {
715 		bdwrite(bp);
716 		return (0);
717 	}
718 }
719 
720 /*
721  * Flush the blocks of a file to disk.
722  *
723  * This function is worthless for vnodes that represent directories. Maybe we
724  * could just do a sync if they try an fsync on a directory file.
725  */
726 int
727 msdosfs_remove(void *v)
728 {
729 	struct vop_remove_args /* {
730 		struct vnode *a_dvp;
731 		struct vnode *a_vp;
732 		struct componentname *a_cnp;
733 	} */ *ap = v;
734 	struct denode *dep = VTODE(ap->a_vp);
735 	struct denode *ddep = VTODE(ap->a_dvp);
736 	int error;
737 
738 	fstrans_start(ap->a_dvp->v_mount, FSTRANS_SHARED);
739 	if (ap->a_vp->v_type == VDIR)
740 		error = EPERM;
741 	else
742 		error = removede(ddep, dep);
743 #ifdef MSDOSFS_DEBUG
744 	printf("msdosfs_remove(), dep %p, v_usecount %d\n",
745 		dep, ap->a_vp->v_usecount);
746 #endif
747 	VN_KNOTE(ap->a_vp, NOTE_DELETE);
748 	VN_KNOTE(ap->a_dvp, NOTE_WRITE);
749 	if (ddep == dep)
750 		vrele(ap->a_vp);
751 	else
752 		vput(ap->a_vp);	/* causes msdosfs_inactive() to be called
753 				 * via vrele() */
754 	vput(ap->a_dvp);
755 	fstrans_done(ap->a_dvp->v_mount);
756 	return (error);
757 }
758 
759 /*
760  * Renames on files require moving the denode to a new hash queue since the
761  * denode's location is used to compute which hash queue to put the file
762  * in. Unless it is a rename in place.  For example "mv a b".
763  *
764  * What follows is the basic algorithm:
765  *
766  * if (file move) {
767  *	if (dest file exists) {
768  *		remove dest file
769  *	}
770  *	if (dest and src in same directory) {
771  *		rewrite name in existing directory slot
772  *	} else {
773  *		write new entry in dest directory
774  *		update offset and dirclust in denode
775  *		move denode to new hash chain
776  *		clear old directory entry
777  *	}
778  * } else {
779  *	directory move
780  *	if (dest directory exists) {
781  *		if (dest is not empty) {
782  *			return ENOTEMPTY
783  *		}
784  *		remove dest directory
785  *	}
786  *	if (dest and src in same directory) {
787  *		rewrite name in existing entry
788  *	} else {
789  *		be sure dest is not a child of src directory
790  *		write entry in dest directory
791  *		update "." and ".." in moved directory
792  *		update offset and dirclust in denode
793  *		move denode to new hash chain
794  *		clear old directory entry for moved directory
795  *	}
796  * }
797  *
798  * On entry:
799  *	source's parent directory is unlocked
800  *	source file or directory is unlocked
801  *	destination's parent directory is locked
802  *	destination file or directory is locked if it exists
803  *
804  * On exit:
805  *	all denodes should be released
806  *
807  * Notes:
808  * I'm not sure how the memory containing the pathnames pointed at by the
809  * componentname structures is freed, there may be some memory bleeding
810  * for each rename done.
811  *
812  * --More-- Notes:
813  * This routine needs help.  badly.
814  */
815 int
816 msdosfs_rename(void *v)
817 {
818 	struct vop_rename_args /* {
819 		struct vnode *a_fdvp;
820 		struct vnode *a_fvp;
821 		struct componentname *a_fcnp;
822 		struct vnode *a_tdvp;
823 		struct vnode *a_tvp;
824 		struct componentname *a_tcnp;
825 	} */ *ap = v;
826 	struct vnode *tvp = ap->a_tvp;
827 	struct vnode *tdvp = ap->a_tdvp;
828 	struct vnode *fvp = ap->a_fvp;
829 	struct vnode *fdvp = ap->a_fdvp;
830 	struct mount *mp = fdvp->v_mount;
831 	struct componentname *tcnp = ap->a_tcnp;
832 	struct componentname *fcnp = ap->a_fcnp;
833 	struct denode *ip, *xp, *dp, *zp;
834 	u_char toname[12], oldname[12];
835 	u_long from_diroffset, to_diroffset;
836 	u_char to_count;
837 	int doingdirectory = 0, newparent = 0;
838 	int error;
839 	u_long cn;
840 	daddr_t bn;
841 	struct msdosfsmount *pmp;
842 	struct direntry *dotdotp;
843 	struct buf *bp;
844 
845 	pmp = VFSTOMSDOSFS(fdvp->v_mount);
846 
847 	/*
848 	 * Check for cross-device rename.
849 	 */
850 	if ((fvp->v_mount != tdvp->v_mount) ||
851 	    (tvp && (fvp->v_mount != tvp->v_mount))) {
852 		error = EXDEV;
853 abortit:
854 		VOP_ABORTOP(tdvp, tcnp);
855 		if (tdvp == tvp)
856 			vrele(tdvp);
857 		else
858 			vput(tdvp);
859 		if (tvp)
860 			vput(tvp);
861 		VOP_ABORTOP(fdvp, fcnp);
862 		vrele(fdvp);
863 		vrele(fvp);
864 		return (error);
865 	}
866 
867 	/*
868 	 * If source and dest are the same, do nothing.
869 	 */
870 	if (tvp == fvp) {
871 		error = 0;
872 		goto abortit;
873 	}
874 
875 	/*
876 	 * XXX: This can deadlock since we hold tdvp/tvp locked.
877 	 * But I'm not going to fix it now.
878 	 */
879 	if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0)
880 		goto abortit;
881 	dp = VTODE(fdvp);
882 	ip = VTODE(fvp);
883 
884 	/*
885 	 * Be sure we are not renaming ".", "..", or an alias of ".". This
886 	 * leads to a crippled directory tree.  It's pretty tough to do a
887 	 * "ls" or "pwd" with the "." directory entry missing, and "cd .."
888 	 * doesn't work if the ".." entry is missing.
889 	 */
890 	if (ip->de_Attributes & ATTR_DIRECTORY) {
891 		/*
892 		 * Avoid ".", "..", and aliases of "." for obvious reasons.
893 		 */
894 		if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
895 		    dp == ip ||
896 		    (fcnp->cn_flags & ISDOTDOT) ||
897 		    (tcnp->cn_flags & ISDOTDOT) ||
898 		    (ip->de_flag & DE_RENAME)) {
899 			VOP_UNLOCK(fvp);
900 			error = EINVAL;
901 			goto abortit;
902 		}
903 		ip->de_flag |= DE_RENAME;
904 		doingdirectory++;
905 	}
906 	VN_KNOTE(fdvp, NOTE_WRITE);		/* XXXLUKEM/XXX: right place? */
907 
908 	fstrans_start(mp, FSTRANS_SHARED);
909 	/*
910 	 * When the target exists, both the directory
911 	 * and target vnodes are returned locked.
912 	 */
913 	dp = VTODE(tdvp);
914 	xp = tvp ? VTODE(tvp) : NULL;
915 	/*
916 	 * Remember direntry place to use for destination
917 	 */
918 	to_diroffset = dp->de_fndoffset;
919 	to_count = dp->de_fndcnt;
920 
921 	/*
922 	 * If ".." must be changed (ie the directory gets a new
923 	 * parent) then the source directory must not be in the
924 	 * directory hierarchy above the target, as this would
925 	 * orphan everything below the source directory. Also
926 	 * the user must have write permission in the source so
927 	 * as to be able to change "..". We must repeat the call
928 	 * to namei, as the parent directory is unlocked by the
929 	 * call to doscheckpath().
930 	 */
931 	error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred);
932 	VOP_UNLOCK(fvp);
933 	if (VTODE(fdvp)->de_StartCluster != VTODE(tdvp)->de_StartCluster)
934 		newparent = 1;
935 
936 	if (doingdirectory && newparent) {
937 		if (error)	/* write access check above */
938 			goto tdvpbad;
939 		if (xp != NULL)
940 			vput(tvp);
941 		tvp = NULL;
942 		/*
943 		 * doscheckpath() vput()'s tdvp (dp == VTODE(tdvp)),
944 		 * so we have to get an extra ref to it first, and
945 		 * because it's been unlocked we need to do a relookup
946 		 * afterwards in case tvp has changed.
947 		 */
948 		vref(tdvp);
949 		if ((error = doscheckpath(ip, dp)) != 0)
950 			goto bad;
951 		vn_lock(tdvp, LK_EXCLUSIVE | LK_RETRY);
952 		if ((error = relookup(tdvp, &tvp, tcnp, 0)) != 0) {
953 			VOP_UNLOCK(tdvp);
954 			goto bad;
955 		}
956 		dp = VTODE(tdvp);
957 		xp = tvp ? VTODE(tvp) : NULL;
958 	}
959 
960 	if (xp != NULL) {
961 		/*
962 		 * Target must be empty if a directory and have no links
963 		 * to it. Also, ensure source and target are compatible
964 		 * (both directories, or both not directories).
965 		 */
966 		if (xp->de_Attributes & ATTR_DIRECTORY) {
967 			if (!dosdirempty(xp)) {
968 				error = ENOTEMPTY;
969 				goto tdvpbad;
970 			}
971 			if (!doingdirectory) {
972 				error = ENOTDIR;
973 				goto tdvpbad;
974 			}
975 		} else if (doingdirectory) {
976 			error = EISDIR;
977 			goto tdvpbad;
978 		}
979 		if ((error = removede(dp, xp)) != 0)
980 			goto tdvpbad;
981 		VN_KNOTE(tdvp, NOTE_WRITE);
982 		VN_KNOTE(tvp, NOTE_DELETE);
983 		cache_purge(tvp);
984 		vput(tvp);
985 		tvp = NULL;
986 		xp = NULL;
987 	}
988 
989 	/*
990 	 * Convert the filename in tcnp into a dos filename. We copy this
991 	 * into the denode and directory entry for the destination
992 	 * file/directory.
993 	 */
994 	if ((error = uniqdosname(VTODE(tdvp), tcnp, toname)) != 0) {
995 		fstrans_done(mp);
996 		goto abortit;
997 	}
998 
999 	/*
1000 	 * Since from wasn't locked at various places above,
1001 	 * have to do a relookup here.
1002 	 */
1003 	fcnp->cn_flags &= ~MODMASK;
1004 	fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
1005 	VOP_UNLOCK(tdvp);
1006 	vn_lock(fdvp, LK_EXCLUSIVE | LK_RETRY);
1007 	if ((error = relookup(fdvp, &fvp, fcnp, 0))) {
1008 		VOP_UNLOCK(fdvp);
1009 		vrele(ap->a_fvp);
1010 		vrele(tdvp);
1011 		fstrans_done(mp);
1012 		return (error);
1013 	}
1014 	if (fvp == NULL) {
1015 		/*
1016 		 * From name has disappeared.
1017 		 */
1018 		if (doingdirectory)
1019 			panic("rename: lost dir entry");
1020 		vput(fdvp);
1021 		vrele(ap->a_fvp);
1022 		vrele(tdvp);
1023 		fstrans_done(mp);
1024 		return 0;
1025 	}
1026 	VOP_UNLOCK(fdvp);
1027 	xp = VTODE(fvp);
1028 	zp = VTODE(fdvp);
1029 	from_diroffset = zp->de_fndoffset;
1030 
1031 	/*
1032 	 * Ensure that the directory entry still exists and has not
1033 	 * changed till now. If the source is a file the entry may
1034 	 * have been unlinked or renamed. In either case there is
1035 	 * no further work to be done. If the source is a directory
1036 	 * then it cannot have been rmdir'ed or renamed; this is
1037 	 * prohibited by the DE_RENAME flag.
1038 	 */
1039 	if (xp != ip) {
1040 		if (doingdirectory)
1041 			panic("rename: lost dir entry");
1042 		vrele(ap->a_fvp);
1043 		xp = NULL;
1044 	} else {
1045 		vrele(fvp);
1046 		xp = NULL;
1047 
1048 		/*
1049 		 * First write a new entry in the destination
1050 		 * directory and mark the entry in the source directory
1051 		 * as deleted.  Then move the denode to the correct hash
1052 		 * chain for its new location in the filesystem.  And, if
1053 		 * we moved a directory, then update its .. entry to point
1054 		 * to the new parent directory.
1055 		 */
1056 		memcpy(oldname, ip->de_Name, 11);
1057 		memcpy(ip->de_Name, toname, 11);	/* update denode */
1058 		dp->de_fndoffset = to_diroffset;
1059 		dp->de_fndcnt = to_count;
1060 		error = createde(ip, dp, (struct denode **)0, tcnp);
1061 		if (error) {
1062 			memcpy(ip->de_Name, oldname, 11);
1063 			VOP_UNLOCK(fvp);
1064 			goto bad;
1065 		}
1066 		ip->de_refcnt++;
1067 		zp->de_fndoffset = from_diroffset;
1068 		if ((error = removede(zp, ip)) != 0) {
1069 			/* XXX should really panic here, fs is corrupt */
1070 			VOP_UNLOCK(fvp);
1071 			goto bad;
1072 		}
1073 		cache_purge(fvp);
1074 		if (!doingdirectory) {
1075 			error = pcbmap(dp, de_cluster(pmp, to_diroffset), 0,
1076 				       &ip->de_dirclust, 0);
1077 			if (error) {
1078 				/* XXX should really panic here, fs is corrupt */
1079 				VOP_UNLOCK(fvp);
1080 				goto bad;
1081 			}
1082 			ip->de_diroffset = to_diroffset;
1083 			if (ip->de_dirclust != MSDOSFSROOT)
1084 				ip->de_diroffset &= pmp->pm_crbomask;
1085 		}
1086 		reinsert(ip);
1087 	}
1088 
1089 	/*
1090 	 * If we moved a directory to a new parent directory, then we must
1091 	 * fixup the ".." entry in the moved directory.
1092 	 */
1093 	if (doingdirectory && newparent) {
1094 		cn = ip->de_StartCluster;
1095 		if (cn == MSDOSFSROOT) {
1096 			/* this should never happen */
1097 			panic("msdosfs_rename: updating .. in root directory?");
1098 		} else
1099 			bn = cntobn(pmp, cn);
1100 		error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn),
1101 		    pmp->pm_bpcluster, NOCRED, B_MODIFY, &bp);
1102 		if (error) {
1103 			/* XXX should really panic here, fs is corrupt */
1104 			VOP_UNLOCK(fvp);
1105 			goto bad;
1106 		}
1107 		dotdotp = (struct direntry *)bp->b_data + 1;
1108 		putushort(dotdotp->deStartCluster, dp->de_StartCluster);
1109 		if (FAT32(pmp)) {
1110 			putushort(dotdotp->deHighClust,
1111 				dp->de_StartCluster >> 16);
1112 		} else {
1113 			putushort(dotdotp->deHighClust, 0);
1114 		}
1115 		if ((error = bwrite(bp)) != 0) {
1116 			/* XXX should really panic here, fs is corrupt */
1117 			VOP_UNLOCK(fvp);
1118 			goto bad;
1119 		}
1120 	}
1121 
1122 	VN_KNOTE(fvp, NOTE_RENAME);
1123 	VOP_UNLOCK(fvp);
1124 bad:
1125 	if (tvp)
1126 		vput(tvp);
1127 	vrele(tdvp);
1128 	ip->de_flag &= ~DE_RENAME;
1129 	vrele(fdvp);
1130 	vrele(fvp);
1131 	fstrans_done(mp);
1132 	return (error);
1133 
1134 	/* XXX: uuuh */
1135 tdvpbad:
1136 	VOP_UNLOCK(tdvp);
1137 	goto bad;
1138 }
1139 
1140 static const struct {
1141 	struct direntry dot;
1142 	struct direntry dotdot;
1143 } dosdirtemplate = {
1144 	{	".       ", "   ",			/* the . entry */
1145 		ATTR_DIRECTORY,				/* file attribute */
1146 		0,	 				/* reserved */
1147 		0, { 0, 0 }, { 0, 0 },			/* create time & date */
1148 		{ 0, 0 },				/* access date */
1149 		{ 0, 0 },				/* high bits of start cluster */
1150 		{ 210, 4 }, { 210, 4 },			/* modify time & date */
1151 		{ 0, 0 },				/* startcluster */
1152 		{ 0, 0, 0, 0 } 				/* filesize */
1153 	},
1154 	{	"..      ", "   ",			/* the .. entry */
1155 		ATTR_DIRECTORY,				/* file attribute */
1156 		0,	 				/* reserved */
1157 		0, { 0, 0 }, { 0, 0 },			/* create time & date */
1158 		{ 0, 0 },				/* access date */
1159 		{ 0, 0 },				/* high bits of start cluster */
1160 		{ 210, 4 }, { 210, 4 },			/* modify time & date */
1161 		{ 0, 0 },				/* startcluster */
1162 		{ 0, 0, 0, 0 }				/* filesize */
1163 	}
1164 };
1165 
1166 int
1167 msdosfs_mkdir(void *v)
1168 {
1169 	struct vop_mkdir_v3_args /* {
1170 		struct vnode *a_dvp;
1171 		struvt vnode **a_vpp;
1172 		struvt componentname *a_cnp;
1173 		struct vattr *a_vap;
1174 	} */ *ap = v;
1175 	struct componentname *cnp = ap->a_cnp;
1176 	struct denode ndirent;
1177 	struct denode *dep;
1178 	struct denode *pdep = VTODE(ap->a_dvp);
1179 	int error;
1180 	int bn;
1181 	u_long newcluster, pcl;
1182 	daddr_t lbn;
1183 	struct direntry *denp;
1184 	struct msdosfsmount *pmp = pdep->de_pmp;
1185 	struct buf *bp;
1186 	int async = pdep->de_pmp->pm_mountp->mnt_flag & MNT_ASYNC;
1187 
1188 	fstrans_start(ap->a_dvp->v_mount, FSTRANS_SHARED);
1189 	/*
1190 	 * If this is the root directory and there is no space left we
1191 	 * can't do anything.  This is because the root directory can not
1192 	 * change size.
1193 	 */
1194 	if (pdep->de_StartCluster == MSDOSFSROOT
1195 	    && pdep->de_fndoffset >= pdep->de_FileSize) {
1196 		error = ENOSPC;
1197 		goto bad2;
1198 	}
1199 
1200 	/*
1201 	 * Allocate a cluster to hold the about to be created directory.
1202 	 */
1203 	error = clusteralloc(pmp, 0, 1, &newcluster, NULL);
1204 	if (error)
1205 		goto bad2;
1206 
1207 	memset(&ndirent, 0, sizeof(ndirent));
1208 	ndirent.de_pmp = pmp;
1209 	ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE;
1210 	DETIMES(&ndirent, NULL, NULL, NULL, pmp->pm_gmtoff);
1211 
1212 	/*
1213 	 * Now fill the cluster with the "." and ".." entries. And write
1214 	 * the cluster to disk.  This way it is there for the parent
1215 	 * directory to be pointing at if there were a crash.
1216 	 */
1217 	bn = cntobn(pmp, newcluster);
1218 	lbn = de_bn2kb(pmp, bn);
1219 	/* always succeeds */
1220 	bp = getblk(pmp->pm_devvp, lbn, pmp->pm_bpcluster, 0, 0);
1221 	memset(bp->b_data, 0, pmp->pm_bpcluster);
1222 	memcpy(bp->b_data, &dosdirtemplate, sizeof dosdirtemplate);
1223 	denp = (struct direntry *)bp->b_data;
1224 	putushort(denp[0].deStartCluster, newcluster);
1225 	putushort(denp[0].deCDate, ndirent.de_CDate);
1226 	putushort(denp[0].deCTime, ndirent.de_CTime);
1227 	denp[0].deCHundredth = ndirent.de_CHun;
1228 	putushort(denp[0].deADate, ndirent.de_ADate);
1229 	putushort(denp[0].deMDate, ndirent.de_MDate);
1230 	putushort(denp[0].deMTime, ndirent.de_MTime);
1231 	pcl = pdep->de_StartCluster;
1232 	if (FAT32(pmp) && pcl == pmp->pm_rootdirblk)
1233 		pcl = 0;
1234 	putushort(denp[1].deStartCluster, pcl);
1235 	putushort(denp[1].deCDate, ndirent.de_CDate);
1236 	putushort(denp[1].deCTime, ndirent.de_CTime);
1237 	denp[1].deCHundredth = ndirent.de_CHun;
1238 	putushort(denp[1].deADate, ndirent.de_ADate);
1239 	putushort(denp[1].deMDate, ndirent.de_MDate);
1240 	putushort(denp[1].deMTime, ndirent.de_MTime);
1241 	if (FAT32(pmp)) {
1242 		putushort(denp[0].deHighClust, newcluster >> 16);
1243 		putushort(denp[1].deHighClust, pdep->de_StartCluster >> 16);
1244 	} else {
1245 		putushort(denp[0].deHighClust, 0);
1246 		putushort(denp[1].deHighClust, 0);
1247 	}
1248 
1249 	if (async)
1250 		bdwrite(bp);
1251 	else if ((error = bwrite(bp)) != 0)
1252 		goto bad;
1253 
1254 	/*
1255 	 * Now build up a directory entry pointing to the newly allocated
1256 	 * cluster.  This will be written to an empty slot in the parent
1257 	 * directory.
1258 	 */
1259 	if ((error = uniqdosname(pdep, cnp, ndirent.de_Name)) != 0)
1260 		goto bad;
1261 
1262 	ndirent.de_Attributes = ATTR_DIRECTORY;
1263 	ndirent.de_StartCluster = newcluster;
1264 	ndirent.de_FileSize = 0;
1265 	ndirent.de_dev = pdep->de_dev;
1266 	ndirent.de_devvp = pdep->de_devvp;
1267 	if ((error = createde(&ndirent, pdep, &dep, cnp)) != 0)
1268 		goto bad;
1269 	VN_KNOTE(ap->a_dvp, NOTE_WRITE | NOTE_LINK);
1270 	*ap->a_vpp = DETOV(dep);
1271 	fstrans_done(ap->a_dvp->v_mount);
1272 	return (0);
1273 
1274 bad:
1275 	clusterfree(pmp, newcluster, NULL);
1276 bad2:
1277 	fstrans_done(ap->a_dvp->v_mount);
1278 	return (error);
1279 }
1280 
1281 int
1282 msdosfs_rmdir(void *v)
1283 {
1284 	struct vop_rmdir_args /* {
1285 		struct vnode *a_dvp;
1286 		struct vnode *a_vp;
1287 		struct componentname *a_cnp;
1288 	} */ *ap = v;
1289 	struct vnode *vp = ap->a_vp;
1290 	struct vnode *dvp = ap->a_dvp;
1291 	struct mount *mp = dvp->v_mount;
1292 	struct componentname *cnp = ap->a_cnp;
1293 	struct denode *ip, *dp;
1294 	int error;
1295 
1296 	ip = VTODE(vp);
1297 	dp = VTODE(dvp);
1298 	/*
1299 	 * No rmdir "." please.
1300 	 */
1301 	if (dp == ip) {
1302 		vrele(dvp);
1303 		vput(vp);
1304 		return (EINVAL);
1305 	}
1306 	fstrans_start(mp, FSTRANS_SHARED);
1307 	/*
1308 	 * Verify the directory is empty (and valid).
1309 	 * (Rmdir ".." won't be valid since
1310 	 *  ".." will contain a reference to
1311 	 *  the current directory and thus be
1312 	 *  non-empty.)
1313 	 */
1314 	error = 0;
1315 	if (!dosdirempty(ip) || ip->de_flag & DE_RENAME) {
1316 		error = ENOTEMPTY;
1317 		goto out;
1318 	}
1319 	/*
1320 	 * Delete the entry from the directory.  For dos filesystems this
1321 	 * gets rid of the directory entry on disk, the in memory copy
1322 	 * still exists but the de_refcnt is <= 0.  This prevents it from
1323 	 * being found by deget().  When the vput() on dep is done we give
1324 	 * up access and eventually msdosfs_reclaim() will be called which
1325 	 * will remove it from the denode cache.
1326 	 */
1327 	if ((error = removede(dp, ip)) != 0)
1328 		goto out;
1329 	/*
1330 	 * This is where we decrement the link count in the parent
1331 	 * directory.  Since dos filesystems don't do this we just purge
1332 	 * the name cache and let go of the parent directory denode.
1333 	 */
1334 	VN_KNOTE(dvp, NOTE_WRITE | NOTE_LINK);
1335 	cache_purge(dvp);
1336 	vput(dvp);
1337 	dvp = NULL;
1338 	/*
1339 	 * Truncate the directory that is being deleted.
1340 	 */
1341 	error = detrunc(ip, (u_long)0, IO_SYNC, cnp->cn_cred);
1342 	cache_purge(vp);
1343 out:
1344 	VN_KNOTE(vp, NOTE_DELETE);
1345 	if (dvp)
1346 		vput(dvp);
1347 	vput(vp);
1348 	fstrans_done(mp);
1349 	return (error);
1350 }
1351 
1352 int
1353 msdosfs_readdir(void *v)
1354 {
1355 	struct vop_readdir_args /* {
1356 		struct vnode *a_vp;
1357 		struct uio *a_uio;
1358 		kauth_cred_t a_cred;
1359 		int *a_eofflag;
1360 		off_t **a_cookies;
1361 		int *a_ncookies;
1362 	} */ *ap = v;
1363 	int error = 0;
1364 	int diff;
1365 	long n;
1366 	int blsize;
1367 	long on;
1368 	long lost;
1369 	long count;
1370 	u_long cn;
1371 	ino_t fileno;
1372 	u_long dirsperblk;
1373 	long bias = 0;
1374 	daddr_t bn, lbn;
1375 	struct buf *bp;
1376 	struct denode *dep = VTODE(ap->a_vp);
1377 	struct msdosfsmount *pmp = dep->de_pmp;
1378 	struct direntry *dentp;
1379 	struct dirent *dirbuf;
1380 	struct uio *uio = ap->a_uio;
1381 	off_t *cookies = NULL;
1382 	int ncookies = 0, nc = 0;
1383 	off_t offset, uio_off;
1384 	int chksum = -1;
1385 
1386 #ifdef MSDOSFS_DEBUG
1387 	printf("msdosfs_readdir(): vp %p, uio %p, cred %p, eofflagp %p\n",
1388 	    ap->a_vp, uio, ap->a_cred, ap->a_eofflag);
1389 #endif
1390 
1391 	/*
1392 	 * msdosfs_readdir() won't operate properly on regular files since
1393 	 * it does i/o only with the filesystem vnode, and hence can
1394 	 * retrieve the wrong block from the buffer cache for a plain file.
1395 	 * So, fail attempts to readdir() on a plain file.
1396 	 */
1397 	if ((dep->de_Attributes & ATTR_DIRECTORY) == 0)
1398 		return (ENOTDIR);
1399 
1400 	/*
1401 	 * If the user buffer is smaller than the size of one dos directory
1402 	 * entry or the file offset is not a multiple of the size of a
1403 	 * directory entry, then we fail the read.
1404 	 */
1405 	count = uio->uio_resid & ~(sizeof(struct direntry) - 1);
1406 	offset = uio->uio_offset;
1407 	if (count < sizeof(struct direntry) ||
1408 	    (offset & (sizeof(struct direntry) - 1)))
1409 		return (EINVAL);
1410 	lost = uio->uio_resid - count;
1411 	uio->uio_resid = count;
1412 	uio_off = uio->uio_offset;
1413 
1414 	fstrans_start(ap->a_vp->v_mount, FSTRANS_SHARED);
1415 
1416 	/* Allocate a temporary dirent buffer. */
1417 	dirbuf = malloc(sizeof(struct dirent), M_MSDOSFSTMP, M_WAITOK | M_ZERO);
1418 
1419 	if (ap->a_ncookies) {
1420 		nc = uio->uio_resid / _DIRENT_MINSIZE((struct dirent *)0);
1421 		cookies = malloc(nc * sizeof (off_t), M_TEMP, M_WAITOK);
1422 		*ap->a_cookies = cookies;
1423 	}
1424 
1425 	dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry);
1426 
1427 	/*
1428 	 * If they are reading from the root directory then, we simulate
1429 	 * the . and .. entries since these don't exist in the root
1430 	 * directory.  We also set the offset bias to make up for having to
1431 	 * simulate these entries. By this I mean that at file offset 64 we
1432 	 * read the first entry in the root directory that lives on disk.
1433 	 */
1434 	if (dep->de_StartCluster == MSDOSFSROOT
1435 	    || (FAT32(pmp) && dep->de_StartCluster == pmp->pm_rootdirblk)) {
1436 #if 0
1437 		printf("msdosfs_readdir(): going after . or .. in root dir, "
1438 		    "offset %" PRIu64 "\n", offset);
1439 #endif
1440 		bias = 2 * sizeof(struct direntry);
1441 		if (offset < bias) {
1442 			for (n = (int)offset / sizeof(struct direntry);
1443 			     n < 2; n++) {
1444 				if (FAT32(pmp))
1445 					dirbuf->d_fileno = cntobn(pmp,
1446 					     (ino_t)pmp->pm_rootdirblk)
1447 					     * dirsperblk;
1448 				else
1449 					dirbuf->d_fileno = 1;
1450 				dirbuf->d_type = DT_DIR;
1451 				switch (n) {
1452 				case 0:
1453 					dirbuf->d_namlen = 1;
1454 					strlcpy(dirbuf->d_name, ".",
1455 					    sizeof(dirbuf->d_name));
1456 					break;
1457 				case 1:
1458 					dirbuf->d_namlen = 2;
1459 					strlcpy(dirbuf->d_name, "..",
1460 					    sizeof(dirbuf->d_name));
1461 					break;
1462 				}
1463 				dirbuf->d_reclen = _DIRENT_SIZE(dirbuf);
1464 				if (uio->uio_resid < dirbuf->d_reclen)
1465 					goto out;
1466 				error = uiomove(dirbuf, dirbuf->d_reclen, uio);
1467 				if (error)
1468 					goto out;
1469 				offset += sizeof(struct direntry);
1470 				uio_off = offset;
1471 				if (cookies) {
1472 					*cookies++ = offset;
1473 					ncookies++;
1474 					if (ncookies >= nc)
1475 						goto out;
1476 				}
1477 			}
1478 		}
1479 	}
1480 
1481 	while (uio->uio_resid > 0) {
1482 		lbn = de_cluster(pmp, offset - bias);
1483 		on = (offset - bias) & pmp->pm_crbomask;
1484 		n = MIN(pmp->pm_bpcluster - on, uio->uio_resid);
1485 		diff = dep->de_FileSize - (offset - bias);
1486 		if (diff <= 0)
1487 			break;
1488 		n = MIN(n, diff);
1489 		if ((error = pcbmap(dep, lbn, &bn, &cn, &blsize)) != 0)
1490 			break;
1491 		error = bread(pmp->pm_devvp, de_bn2kb(pmp, bn), blsize,
1492 		    NOCRED, 0, &bp);
1493 		if (error) {
1494 			goto bad;
1495 		}
1496 		n = MIN(n, blsize - bp->b_resid);
1497 
1498 		/*
1499 		 * Convert from dos directory entries to fs-independent
1500 		 * directory entries.
1501 		 */
1502 		for (dentp = (struct direntry *)((char *)bp->b_data + on);
1503 		     (char *)dentp < (char *)bp->b_data + on + n;
1504 		     dentp++, offset += sizeof(struct direntry)) {
1505 #if 0
1506 
1507 			printf("rd: dentp %08x prev %08x crnt %08x deName %02x attr %02x\n",
1508 			    dentp, prev, crnt, dentp->deName[0], dentp->deAttributes);
1509 #endif
1510 			/*
1511 			 * If this is an unused entry, we can stop.
1512 			 */
1513 			if (dentp->deName[0] == SLOT_EMPTY) {
1514 				brelse(bp, 0);
1515 				goto out;
1516 			}
1517 			/*
1518 			 * Skip deleted entries.
1519 			 */
1520 			if (dentp->deName[0] == SLOT_DELETED) {
1521 				chksum = -1;
1522 				continue;
1523 			}
1524 
1525 			/*
1526 			 * Handle Win95 long directory entries
1527 			 */
1528 			if (dentp->deAttributes == ATTR_WIN95) {
1529 				if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
1530 					continue;
1531 				chksum = win2unixfn((struct winentry *)dentp,
1532 				    dirbuf, chksum);
1533 				continue;
1534 			}
1535 
1536 			/*
1537 			 * Skip volume labels
1538 			 */
1539 			if (dentp->deAttributes & ATTR_VOLUME) {
1540 				chksum = -1;
1541 				continue;
1542 			}
1543 			/*
1544 			 * This computation of d_fileno must match
1545 			 * the computation of va_fileid in
1546 			 * msdosfs_getattr.
1547 			 */
1548 			if (dentp->deAttributes & ATTR_DIRECTORY) {
1549 				fileno = getushort(dentp->deStartCluster);
1550 				if (FAT32(pmp))
1551 					fileno |= ((ino_t)getushort(dentp->deHighClust)) << 16;
1552 				/* if this is the root directory */
1553 				if (fileno == MSDOSFSROOT)
1554 					if (FAT32(pmp))
1555 						fileno = cntobn(pmp,
1556 						    (ino_t)pmp->pm_rootdirblk)
1557 						    * dirsperblk;
1558 					else
1559 						fileno = 1;
1560 				else
1561 					fileno = cntobn(pmp, fileno) * dirsperblk;
1562 				dirbuf->d_fileno = fileno;
1563 				dirbuf->d_type = DT_DIR;
1564 			} else {
1565 				dirbuf->d_fileno =
1566 				    offset / sizeof(struct direntry);
1567 				dirbuf->d_type = DT_REG;
1568 			}
1569 			if (chksum != winChksum(dentp->deName))
1570 				dirbuf->d_namlen = dos2unixfn(dentp->deName,
1571 				    (u_char *)dirbuf->d_name,
1572 				    pmp->pm_flags & MSDOSFSMNT_SHORTNAME);
1573 			else
1574 				dirbuf->d_name[dirbuf->d_namlen] = 0;
1575 			chksum = -1;
1576 			dirbuf->d_reclen = _DIRENT_SIZE(dirbuf);
1577 			if (uio->uio_resid < dirbuf->d_reclen) {
1578 				brelse(bp, 0);
1579 				goto out;
1580 			}
1581 			error = uiomove(dirbuf, dirbuf->d_reclen, uio);
1582 			if (error) {
1583 				brelse(bp, 0);
1584 				goto out;
1585 			}
1586 			uio_off = offset + sizeof(struct direntry);
1587 			if (cookies) {
1588 				*cookies++ = offset + sizeof(struct direntry);
1589 				ncookies++;
1590 				if (ncookies >= nc) {
1591 					brelse(bp, 0);
1592 					goto out;
1593 				}
1594 			}
1595 		}
1596 		brelse(bp, 0);
1597 	}
1598 
1599 out:
1600 	uio->uio_offset = uio_off;
1601 	uio->uio_resid += lost;
1602 	if (dep->de_FileSize - (offset - bias) <= 0)
1603 		*ap->a_eofflag = 1;
1604 	else
1605 		*ap->a_eofflag = 0;
1606 
1607 	if (ap->a_ncookies) {
1608 		if (error) {
1609 			free(*ap->a_cookies, M_TEMP);
1610 			*ap->a_ncookies = 0;
1611 			*ap->a_cookies = NULL;
1612 		} else
1613 			*ap->a_ncookies = ncookies;
1614 	}
1615 
1616 bad:
1617 	free(dirbuf, M_MSDOSFSTMP);
1618 	fstrans_done(ap->a_vp->v_mount);
1619 	return (error);
1620 }
1621 
1622 /*
1623  * vp  - address of vnode file the file
1624  * bn  - which cluster we are interested in mapping to a filesystem block number.
1625  * vpp - returns the vnode for the block special file holding the filesystem
1626  *	 containing the file of interest
1627  * bnp - address of where to return the filesystem relative block number
1628  */
1629 int
1630 msdosfs_bmap(void *v)
1631 {
1632 	struct vop_bmap_args /* {
1633 		struct vnode *a_vp;
1634 		daddr_t a_bn;
1635 		struct vnode **a_vpp;
1636 		daddr_t *a_bnp;
1637 		int *a_runp;
1638 	} */ *ap = v;
1639 	struct denode *dep = VTODE(ap->a_vp);
1640 	int run, maxrun;
1641 	daddr_t runbn;
1642 	int status;
1643 
1644 	if (ap->a_vpp != NULL)
1645 		*ap->a_vpp = dep->de_devvp;
1646 	if (ap->a_bnp == NULL)
1647 		return (0);
1648 	status = pcbmap(dep, ap->a_bn, ap->a_bnp, 0, 0);
1649 
1650 	/*
1651 	 * From FreeBSD:
1652 	 * A little kludgy, but we loop calling pcbmap until we
1653 	 * reach the end of the contiguous piece, or reach MAXPHYS.
1654 	 * Since it reduces disk I/Os, the "wasted" CPU is put to
1655 	 * good use (4 to 5 fold sequential read I/O improvement on USB
1656 	 * drives).
1657 	 */
1658 	if (ap->a_runp != NULL) {
1659 		/* taken from ufs_bmap */
1660 		maxrun = ulmin(MAXPHYS / dep->de_pmp->pm_bpcluster - 1,
1661 			       dep->de_pmp->pm_maxcluster - ap->a_bn);
1662 		for (run = 1; run <= maxrun; run++) {
1663 			if (pcbmap(dep, ap->a_bn + run, &runbn, NULL, NULL)
1664 			    != 0 || runbn !=
1665 			            *ap->a_bnp + de_cn2bn(dep->de_pmp, run))
1666 				break;
1667 		}
1668 		*ap->a_runp = run - 1;
1669 	}
1670 
1671 	/*
1672 	 * We need to scale *ap->a_bnp by sector_size/DEV_BSIZE
1673 	 */
1674 	*ap->a_bnp = de_bn2kb(dep->de_pmp, *ap->a_bnp);
1675 	return status;
1676 }
1677 
1678 int
1679 msdosfs_strategy(void *v)
1680 {
1681 	struct vop_strategy_args /* {
1682 		struct vnode *a_vp;
1683 		struct buf *a_bp;
1684 	} */ *ap = v;
1685 	struct vnode *vp = ap->a_vp;
1686 	struct buf *bp = ap->a_bp;
1687 	struct denode *dep = VTODE(bp->b_vp);
1688 	int error = 0;
1689 
1690 	if (vp->v_type == VBLK || vp->v_type == VCHR)
1691 		panic("msdosfs_strategy: spec");
1692 	/*
1693 	 * If we don't already know the filesystem relative block number
1694 	 * then get it using pcbmap().  If pcbmap() returns the block
1695 	 * number as -1 then we've got a hole in the file.  DOS filesystems
1696 	 * don't allow files with holes, so we shouldn't ever see this.
1697 	 */
1698 	if (bp->b_blkno == bp->b_lblkno) {
1699 		error = pcbmap(dep, de_bn2cn(dep->de_pmp, bp->b_lblkno),
1700 			       &bp->b_blkno, 0, 0);
1701 		if (error)
1702 			bp->b_blkno = -1;
1703 		if (bp->b_blkno == -1)
1704 			clrbuf(bp);
1705 		else
1706 			bp->b_blkno = de_bn2kb(dep->de_pmp, bp->b_blkno);
1707 	}
1708 	if (bp->b_blkno == -1) {
1709 		biodone(bp);
1710 		return (error);
1711 	}
1712 
1713 	/*
1714 	 * Read/write the block from/to the disk that contains the desired
1715 	 * file block.
1716 	 */
1717 
1718 	vp = dep->de_devvp;
1719 	return (VOP_STRATEGY(vp, bp));
1720 }
1721 
1722 int
1723 msdosfs_print(void *v)
1724 {
1725 	struct vop_print_args /* {
1726 		struct vnode *vp;
1727 	} */ *ap = v;
1728 	struct denode *dep = VTODE(ap->a_vp);
1729 
1730 	printf(
1731 	    "tag VT_MSDOSFS, startcluster %ld, dircluster %ld, diroffset %ld ",
1732 	    dep->de_StartCluster, dep->de_dirclust, dep->de_diroffset);
1733 	printf(" dev %llu, %llu ", (unsigned long long)major(dep->de_dev),
1734 	    (unsigned long long)minor(dep->de_dev));
1735 	printf("\n");
1736 	return (0);
1737 }
1738 
1739 int
1740 msdosfs_advlock(void *v)
1741 {
1742 	struct vop_advlock_args /* {
1743 		struct vnode *a_vp;
1744 		void *a_id;
1745 		int a_op;
1746 		struct flock *a_fl;
1747 		int a_flags;
1748 	} */ *ap = v;
1749 	struct denode *dep = VTODE(ap->a_vp);
1750 
1751 	return lf_advlock(ap, &dep->de_lockf, dep->de_FileSize);
1752 }
1753 
1754 int
1755 msdosfs_pathconf(void *v)
1756 {
1757 	struct vop_pathconf_args /* {
1758 		struct vnode *a_vp;
1759 		int a_name;
1760 		register_t *a_retval;
1761 	} */ *ap = v;
1762 
1763 	switch (ap->a_name) {
1764 	case _PC_LINK_MAX:
1765 		*ap->a_retval = 1;
1766 		return (0);
1767 	case _PC_NAME_MAX:
1768 		*ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_namemax;
1769 		return (0);
1770 	case _PC_PATH_MAX:
1771 		*ap->a_retval = PATH_MAX;
1772 		return (0);
1773 	case _PC_CHOWN_RESTRICTED:
1774 		*ap->a_retval = 1;
1775 		return (0);
1776 	case _PC_NO_TRUNC:
1777 		*ap->a_retval = 1;
1778 		return (0);
1779 	case _PC_SYNC_IO:
1780 		*ap->a_retval = 1;
1781 		return (0);
1782 	case _PC_FILESIZEBITS:
1783 		*ap->a_retval = 32;
1784 		return (0);
1785 	default:
1786 		return (EINVAL);
1787 	}
1788 	/* NOTREACHED */
1789 }
1790 
1791 int
1792 msdosfs_fsync(void *v)
1793 {
1794 	struct vop_fsync_args /* {
1795 		struct vnode *a_vp;
1796 		kauth_cred_t a_cred;
1797 		int a_flags;
1798 		off_t offlo;
1799 		off_t offhi;
1800 	} */ *ap = v;
1801 	struct vnode *vp = ap->a_vp;
1802 	int wait;
1803 	int error;
1804 
1805 	fstrans_start(vp->v_mount, FSTRANS_LAZY);
1806 	wait = (ap->a_flags & FSYNC_WAIT) != 0;
1807 	error = vflushbuf(vp, ap->a_flags);
1808 	if (error == 0 && (ap->a_flags & FSYNC_DATAONLY) == 0)
1809 		error = msdosfs_update(vp, NULL, NULL, wait ? UPDATE_WAIT : 0);
1810 
1811 	if (error == 0 && ap->a_flags & FSYNC_CACHE) {
1812 		struct denode *dep = VTODE(vp);
1813 		struct vnode *devvp = dep->de_devvp;
1814 
1815 		int l = 0;
1816 		error = VOP_IOCTL(devvp, DIOCCACHESYNC, &l, FWRITE,
1817 					  curlwp->l_cred);
1818 	}
1819 	fstrans_done(vp->v_mount);
1820 
1821 	return (error);
1822 }
1823 
1824 void
1825 msdosfs_detimes(struct denode *dep, const struct timespec *acc,
1826     const struct timespec *mod, const struct timespec *cre, int gmtoff)
1827 {
1828 	struct timespec *ts = NULL, tsb;
1829 
1830 	KASSERT(dep->de_flag & (DE_UPDATE | DE_CREATE | DE_ACCESS));
1831 	/* XXX just call getnanotime early and use result if needed? */
1832 	dep->de_flag |= DE_MODIFIED;
1833 	if (dep->de_flag & DE_UPDATE) {
1834 		if (mod == NULL) {
1835 			getnanotime(&tsb);
1836 			mod = ts = &tsb;
1837 		}
1838 		unix2dostime(mod, gmtoff, &dep->de_MDate, &dep->de_MTime, NULL);
1839 		dep->de_Attributes |= ATTR_ARCHIVE;
1840 	}
1841 	if ((dep->de_pmp->pm_flags & MSDOSFSMNT_NOWIN95) == 0) {
1842 		if (dep->de_flag & DE_ACCESS)  {
1843 			if (acc == NULL)
1844 				acc = ts == NULL ?
1845 				    (getnanotime(&tsb), ts = &tsb) : ts;
1846 			unix2dostime(acc, gmtoff, &dep->de_ADate, NULL, NULL);
1847 		}
1848 		if (dep->de_flag & DE_CREATE) {
1849 			if (cre == NULL)
1850 				cre = ts == NULL ?
1851 				    (getnanotime(&tsb), ts = &tsb) : ts;
1852 			unix2dostime(cre, gmtoff, &dep->de_CDate,
1853 			    &dep->de_CTime, &dep->de_CHun);
1854 		}
1855 	}
1856 
1857 	dep->de_flag &= ~(DE_UPDATE | DE_CREATE | DE_ACCESS);
1858 }
1859 
1860 /* Global vfs data structures for msdosfs */
1861 int (**msdosfs_vnodeop_p)(void *);
1862 const struct vnodeopv_entry_desc msdosfs_vnodeop_entries[] = {
1863 	{ &vop_default_desc, vn_default_error },
1864 	{ &vop_lookup_desc, msdosfs_lookup },		/* lookup */
1865 	{ &vop_create_desc, msdosfs_create },		/* create */
1866 	{ &vop_mknod_desc, genfs_eopnotsupp },		/* mknod */
1867 	{ &vop_open_desc, genfs_nullop },		/* open */
1868 	{ &vop_close_desc, msdosfs_close },		/* close */
1869 	{ &vop_access_desc, msdosfs_access },		/* access */
1870 	{ &vop_getattr_desc, msdosfs_getattr },		/* getattr */
1871 	{ &vop_setattr_desc, msdosfs_setattr },		/* setattr */
1872 	{ &vop_read_desc, msdosfs_read },		/* read */
1873 	{ &vop_write_desc, msdosfs_write },		/* write */
1874 	{ &vop_fcntl_desc, genfs_fcntl },		/* fcntl */
1875 	{ &vop_ioctl_desc, msdosfs_ioctl },		/* ioctl */
1876 	{ &vop_poll_desc, msdosfs_poll },		/* poll */
1877 	{ &vop_kqfilter_desc, genfs_kqfilter },		/* kqfilter */
1878 	{ &vop_revoke_desc, msdosfs_revoke },		/* revoke */
1879 	{ &vop_mmap_desc, msdosfs_mmap },		/* mmap */
1880 	{ &vop_fsync_desc, msdosfs_fsync },		/* fsync */
1881 	{ &vop_seek_desc, msdosfs_seek },		/* seek */
1882 	{ &vop_remove_desc, msdosfs_remove },		/* remove */
1883 	{ &vop_link_desc, genfs_eopnotsupp },		/* link */
1884 	{ &vop_rename_desc, msdosfs_rename },		/* rename */
1885 	{ &vop_mkdir_desc, msdosfs_mkdir },		/* mkdir */
1886 	{ &vop_rmdir_desc, msdosfs_rmdir },		/* rmdir */
1887 	{ &vop_symlink_desc, genfs_eopnotsupp },	/* symlink */
1888 	{ &vop_readdir_desc, msdosfs_readdir },		/* readdir */
1889 	{ &vop_readlink_desc, genfs_einval },		/* readlink */
1890 	{ &vop_abortop_desc, msdosfs_abortop },		/* abortop */
1891 	{ &vop_inactive_desc, msdosfs_inactive },	/* inactive */
1892 	{ &vop_reclaim_desc, msdosfs_reclaim },		/* reclaim */
1893 	{ &vop_lock_desc, genfs_lock },			/* lock */
1894 	{ &vop_unlock_desc, genfs_unlock },		/* unlock */
1895 	{ &vop_bmap_desc, msdosfs_bmap },		/* bmap */
1896 	{ &vop_strategy_desc, msdosfs_strategy },	/* strategy */
1897 	{ &vop_print_desc, msdosfs_print },		/* print */
1898 	{ &vop_islocked_desc, genfs_islocked },		/* islocked */
1899 	{ &vop_pathconf_desc, msdosfs_pathconf },	/* pathconf */
1900 	{ &vop_advlock_desc, msdosfs_advlock },		/* advlock */
1901 	{ &vop_bwrite_desc, vn_bwrite },		/* bwrite */
1902 	{ &vop_getpages_desc, genfs_getpages },		/* getpages */
1903 	{ &vop_putpages_desc, genfs_putpages },		/* putpages */
1904 	{ NULL, NULL }
1905 };
1906 const struct vnodeopv_desc msdosfs_vnodeop_opv_desc =
1907 	{ &msdosfs_vnodeop_p, msdosfs_vnodeop_entries };
1908