xref: /freebsd/sys/fs/msdosfs/msdosfs_vnops.c (revision c98323078dede7579020518ec84cdcb478e5c142)
1 /* $FreeBSD$ */
2 /*	$NetBSD: msdosfs_vnops.c,v 1.68 1998/02/10 14:10:04 mrg Exp $	*/
3 
4 /*-
5  * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
6  * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
7  * All rights reserved.
8  * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *	This product includes software developed by TooLs GmbH.
21  * 4. The name of TooLs GmbH may not be used to endorse or promote products
22  *    derived from this software without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
25  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
29  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
30  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
31  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
32  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
33  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 /*
36  * Written by Paul Popelka (paulp@uts.amdahl.com)
37  *
38  * You can do anything you want with this software, just don't say you wrote
39  * it, and don't remove this notice.
40  *
41  * This software is provided "as is".
42  *
43  * The author supplies this software to be publicly redistributed on the
44  * understanding that the author is not responsible for the correct
45  * functioning of this software in any circumstances and is not liable for
46  * any damages caused by this software.
47  *
48  * October 1992
49  */
50 
51 #include <sys/param.h>
52 #include <sys/systm.h>
53 #include <sys/lockf.h>
54 #include <sys/namei.h>
55 #include <sys/resourcevar.h>	/* defines plimit structure in proc struct */
56 #include <sys/kernel.h>
57 #include <sys/stat.h>
58 #include <sys/bio.h>
59 #include <sys/buf.h>
60 #include <sys/proc.h>
61 #include <sys/mount.h>
62 #include <sys/unistd.h>
63 #include <sys/vnode.h>
64 #include <sys/malloc.h>
65 #include <sys/dirent.h>
66 #include <sys/signalvar.h>
67 
68 #include <vm/vm.h>
69 #include <vm/vm_extern.h>
70 #include <vm/vnode_pager.h>
71 
72 #include <machine/mutex.h>
73 
74 #include <fs/msdosfs/bpb.h>
75 #include <fs/msdosfs/msdosfsmount.h>
76 #include <fs/msdosfs/direntry.h>
77 #include <fs/msdosfs/denode.h>
78 #include <fs/msdosfs/fat.h>
79 
80 #include "opt_msdosfs.h"
81 
82 #define	DOS_FILESIZE_MAX	0xffffffff
83 
84 /*
85  * Prototypes for MSDOSFS vnode operations
86  */
87 static int msdosfs_advlock(struct vop_advlock_args *);
88 static int msdosfs_create(struct vop_create_args *);
89 static int msdosfs_mknod(struct vop_mknod_args *);
90 static int msdosfs_close(struct vop_close_args *);
91 static int msdosfs_access(struct vop_access_args *);
92 static int msdosfs_getattr(struct vop_getattr_args *);
93 static int msdosfs_setattr(struct vop_setattr_args *);
94 static int msdosfs_read(struct vop_read_args *);
95 static int msdosfs_write(struct vop_write_args *);
96 static int msdosfs_fsync(struct vop_fsync_args *);
97 static int msdosfs_remove(struct vop_remove_args *);
98 static int msdosfs_link(struct vop_link_args *);
99 static int msdosfs_rename(struct vop_rename_args *);
100 static int msdosfs_mkdir(struct vop_mkdir_args *);
101 static int msdosfs_rmdir(struct vop_rmdir_args *);
102 static int msdosfs_symlink(struct vop_symlink_args *);
103 static int msdosfs_readdir(struct vop_readdir_args *);
104 static int msdosfs_bmap(struct vop_bmap_args *);
105 static int msdosfs_strategy(struct vop_strategy_args *);
106 static int msdosfs_print(struct vop_print_args *);
107 static int msdosfs_pathconf(struct vop_pathconf_args *ap);
108 
109 /*
110  * Some general notes:
111  *
112  * In the ufs filesystem the inodes, superblocks, and indirect blocks are
113  * read/written using the vnode for the filesystem. Blocks that represent
114  * the contents of a file are read/written using the vnode for the file
115  * (including directories when they are read/written as files). This
116  * presents problems for the dos filesystem because data that should be in
117  * an inode (if dos had them) resides in the directory itself.  Since we
118  * must update directory entries without the benefit of having the vnode
119  * for the directory we must use the vnode for the filesystem.  This means
120  * that when a directory is actually read/written (via read, write, or
121  * readdir, or seek) we must use the vnode for the filesystem instead of
122  * the vnode for the directory as would happen in ufs. This is to insure we
123  * retreive the correct block from the buffer cache since the hash value is
124  * based upon the vnode address and the desired block number.
125  */
126 
127 /*
128  * Create a regular file. On entry the directory to contain the file being
129  * created is locked.  We must release before we return. We must also free
130  * the pathname buffer pointed at by cnp->cn_pnbuf, always on error, or
131  * only if the SAVESTART bit in cn_flags is clear on success.
132  */
133 static int
134 msdosfs_create(ap)
135 	struct vop_create_args /* {
136 		struct vnode *a_dvp;
137 		struct vnode **a_vpp;
138 		struct componentname *a_cnp;
139 		struct vattr *a_vap;
140 	} */ *ap;
141 {
142 	struct componentname *cnp = ap->a_cnp;
143 	struct denode ndirent;
144 	struct denode *dep;
145 	struct denode *pdep = VTODE(ap->a_dvp);
146 	struct timespec ts;
147 	int error;
148 
149 #ifdef MSDOSFS_DEBUG
150 	printf("msdosfs_create(cnp %p, vap %p\n", cnp, ap->a_vap);
151 #endif
152 
153 	/*
154 	 * If this is the root directory and there is no space left we
155 	 * can't do anything.  This is because the root directory can not
156 	 * change size.
157 	 */
158 	if (pdep->de_StartCluster == MSDOSFSROOT
159 	    && pdep->de_fndoffset >= pdep->de_FileSize) {
160 		error = ENOSPC;
161 		goto bad;
162 	}
163 
164 	/*
165 	 * Create a directory entry for the file, then call createde() to
166 	 * have it installed. NOTE: DOS files are always executable.  We
167 	 * use the absence of the owner write bit to make the file
168 	 * readonly.
169 	 */
170 #ifdef DIAGNOSTIC
171 	if ((cnp->cn_flags & HASBUF) == 0)
172 		panic("msdosfs_create: no name");
173 #endif
174 	bzero(&ndirent, sizeof(ndirent));
175 	error = uniqdosname(pdep, cnp, ndirent.de_Name);
176 	if (error)
177 		goto bad;
178 
179 	ndirent.de_Attributes = (ap->a_vap->va_mode & VWRITE) ?
180 				ATTR_ARCHIVE : ATTR_ARCHIVE | ATTR_READONLY;
181 	ndirent.de_LowerCase = 0;
182 	ndirent.de_StartCluster = 0;
183 	ndirent.de_FileSize = 0;
184 	ndirent.de_dev = pdep->de_dev;
185 	ndirent.de_devvp = pdep->de_devvp;
186 	ndirent.de_pmp = pdep->de_pmp;
187 	ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE;
188 	getnanotime(&ts);
189 	DETIMES(&ndirent, &ts, &ts, &ts);
190 	error = createde(&ndirent, pdep, &dep, cnp);
191 	if (error)
192 		goto bad;
193 	*ap->a_vpp = DETOV(dep);
194 	return (0);
195 
196 bad:
197 	return (error);
198 }
199 
200 static int
201 msdosfs_mknod(ap)
202 	struct vop_mknod_args /* {
203 		struct vnode *a_dvp;
204 		struct vnode **a_vpp;
205 		struct componentname *a_cnp;
206 		struct vattr *a_vap;
207 	} */ *ap;
208 {
209     return (EINVAL);
210 }
211 
212 static int
213 msdosfs_close(ap)
214 	struct vop_close_args /* {
215 		struct vnode *a_vp;
216 		int a_fflag;
217 		struct ucred *a_cred;
218 		struct thread *a_td;
219 	} */ *ap;
220 {
221 	struct vnode *vp = ap->a_vp;
222 	struct denode *dep = VTODE(vp);
223 	struct timespec ts;
224 
225 	VI_LOCK(vp);
226 	if (vp->v_usecount > 1) {
227 		getnanotime(&ts);
228 		DETIMES(dep, &ts, &ts, &ts);
229 	}
230 	VI_UNLOCK(vp);
231 	return 0;
232 }
233 
234 static int
235 msdosfs_access(ap)
236 	struct vop_access_args /* {
237 		struct vnode *a_vp;
238 		int a_mode;
239 		struct ucred *a_cred;
240 		struct thread *a_td;
241 	} */ *ap;
242 {
243 	struct vnode *vp = ap->a_vp;
244 	struct denode *dep = VTODE(ap->a_vp);
245 	struct msdosfsmount *pmp = dep->de_pmp;
246 	mode_t file_mode, mode = ap->a_mode;
247 
248 	file_mode = (S_IXUSR|S_IXGRP|S_IXOTH) | (S_IRUSR|S_IRGRP|S_IROTH) |
249 	    ((dep->de_Attributes & ATTR_READONLY) ? 0 : (S_IWUSR|S_IWGRP|S_IWOTH));
250 	file_mode &= (vp->v_type == VDIR ? pmp->pm_dirmask : pmp->pm_mask);
251 
252 	/*
253 	 * Disallow write attempts on read-only filesystems;
254 	 * unless the file is a socket, fifo, or a block or
255 	 * character device resident on the filesystem.
256 	 */
257 	if (mode & VWRITE) {
258 		switch (vp->v_type) {
259 		case VDIR:
260 		case VLNK:
261 		case VREG:
262 			if (vp->v_mount->mnt_flag & MNT_RDONLY)
263 				return (EROFS);
264 			break;
265 		default:
266 			break;
267 		}
268 	}
269 
270 	return (vaccess(vp->v_type, file_mode, pmp->pm_uid, pmp->pm_gid,
271 	    ap->a_mode, ap->a_cred, NULL));
272 }
273 
274 static int
275 msdosfs_getattr(ap)
276 	struct vop_getattr_args /* {
277 		struct vnode *a_vp;
278 		struct vattr *a_vap;
279 		struct ucred *a_cred;
280 		struct thread *a_td;
281 	} */ *ap;
282 {
283 	struct denode *dep = VTODE(ap->a_vp);
284 	struct msdosfsmount *pmp = dep->de_pmp;
285 	struct vattr *vap = ap->a_vap;
286 	mode_t mode;
287 	struct timespec ts;
288 	u_long dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry);
289 	uint64_t fileid;
290 
291 	getnanotime(&ts);
292 	DETIMES(dep, &ts, &ts, &ts);
293 	vap->va_fsid = dev2udev(dep->de_dev);
294 	/*
295 	 * The following computation of the fileid must be the same as that
296 	 * used in msdosfs_readdir() to compute d_fileno. If not, pwd
297 	 * doesn't work.
298 	 */
299 	if (dep->de_Attributes & ATTR_DIRECTORY) {
300 		fileid = (uint64_t)cntobn(pmp, dep->de_StartCluster) *
301 		    dirsperblk;
302 		if (dep->de_StartCluster == MSDOSFSROOT)
303 			fileid = 1;
304 	} else {
305 		fileid = (uint64_t)cntobn(pmp, dep->de_dirclust) *
306 		    dirsperblk;
307 		if (dep->de_dirclust == MSDOSFSROOT)
308 			fileid = (uint64_t)roottobn(pmp, 0) * dirsperblk;
309 		fileid += (uint64_t)dep->de_diroffset / sizeof(struct direntry);
310 	}
311 #ifdef MSDOSFS_LARGE
312 	vap->va_fileid = msdosfs_fileno_map(pmp->pm_mountp, fileid);
313 #else
314 	vap->va_fileid = (long)fileid;
315 #endif
316 	if ((dep->de_Attributes & ATTR_READONLY) == 0)
317 		mode = S_IRWXU|S_IRWXG|S_IRWXO;
318 	else
319 		mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
320 	vap->va_mode = mode &
321 		(ap->a_vp->v_type == VDIR ? pmp->pm_dirmask : pmp->pm_mask);
322 	vap->va_uid = pmp->pm_uid;
323 	vap->va_gid = pmp->pm_gid;
324 	vap->va_nlink = 1;
325 	vap->va_rdev = 0;
326 	vap->va_size = dep->de_FileSize;
327 	dos2unixtime(dep->de_MDate, dep->de_MTime, 0, &vap->va_mtime);
328 	if (pmp->pm_flags & MSDOSFSMNT_LONGNAME) {
329 		dos2unixtime(dep->de_ADate, 0, 0, &vap->va_atime);
330 		dos2unixtime(dep->de_CDate, dep->de_CTime, dep->de_CHun, &vap->va_ctime);
331 	} else {
332 		vap->va_atime = vap->va_mtime;
333 		vap->va_ctime = vap->va_mtime;
334 	}
335 	vap->va_flags = 0;
336 	if ((dep->de_Attributes & ATTR_ARCHIVE) == 0)
337 		vap->va_flags |= SF_ARCHIVED;
338 	vap->va_gen = 0;
339 	vap->va_blocksize = pmp->pm_bpcluster;
340 	vap->va_bytes =
341 	    (dep->de_FileSize + pmp->pm_crbomask) & ~pmp->pm_crbomask;
342 	vap->va_type = ap->a_vp->v_type;
343 	vap->va_filerev = dep->de_modrev;
344 	return (0);
345 }
346 
347 static int
348 msdosfs_setattr(ap)
349 	struct vop_setattr_args /* {
350 		struct vnode *a_vp;
351 		struct vattr *a_vap;
352 		struct ucred *a_cred;
353 		struct thread *a_td;
354 	} */ *ap;
355 {
356 	struct vnode *vp = ap->a_vp;
357 	struct denode *dep = VTODE(ap->a_vp);
358 	struct msdosfsmount *pmp = dep->de_pmp;
359 	struct vattr *vap = ap->a_vap;
360 	struct ucred *cred = ap->a_cred;
361 	int error = 0;
362 
363 #ifdef MSDOSFS_DEBUG
364 	printf("msdosfs_setattr(): vp %p, vap %p, cred %p, p %p\n",
365 	    ap->a_vp, vap, cred, ap->a_td);
366 #endif
367 
368 	/*
369 	 * Check for unsettable attributes.
370 	 */
371 	if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) ||
372 	    (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
373 	    (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
374 	    (vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) {
375 #ifdef MSDOSFS_DEBUG
376 		printf("msdosfs_setattr(): returning EINVAL\n");
377 		printf("    va_type %d, va_nlink %x, va_fsid %lx, va_fileid %lx\n",
378 		    vap->va_type, vap->va_nlink, vap->va_fsid, vap->va_fileid);
379 		printf("    va_blocksize %lx, va_rdev %x, va_bytes %qx, va_gen %lx\n",
380 		    vap->va_blocksize, vap->va_rdev, vap->va_bytes, vap->va_gen);
381 		printf("    va_uid %x, va_gid %x\n",
382 		    vap->va_uid, vap->va_gid);
383 #endif
384 		return (EINVAL);
385 	}
386 	if (vap->va_flags != VNOVAL) {
387 		if (vp->v_mount->mnt_flag & MNT_RDONLY)
388 			return (EROFS);
389 		if (cred->cr_uid != pmp->pm_uid &&
390 		    (error = suser_cred(cred, PRISON_ROOT)))
391 			return (error);
392 		/*
393 		 * We are very inconsistent about handling unsupported
394 		 * attributes.  We ignored the access time and the
395 		 * read and execute bits.  We were strict for the other
396 		 * attributes.
397 		 *
398 		 * Here we are strict, stricter than ufs in not allowing
399 		 * users to attempt to set SF_SETTABLE bits or anyone to
400 		 * set unsupported bits.  However, we ignore attempts to
401 		 * set ATTR_ARCHIVE for directories `cp -pr' from a more
402 		 * sensible filesystem attempts it a lot.
403 		 */
404 		if (suser_cred(cred, PRISON_ROOT)) {
405 			if (vap->va_flags & SF_SETTABLE)
406 				return EPERM;
407 		}
408 		if (vap->va_flags & ~SF_ARCHIVED)
409 			return EOPNOTSUPP;
410 		if (vap->va_flags & SF_ARCHIVED)
411 			dep->de_Attributes &= ~ATTR_ARCHIVE;
412 		else if (!(dep->de_Attributes & ATTR_DIRECTORY))
413 			dep->de_Attributes |= ATTR_ARCHIVE;
414 		dep->de_flag |= DE_MODIFIED;
415 	}
416 
417 	if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) {
418 		uid_t uid;
419 		gid_t gid;
420 
421 		if (vp->v_mount->mnt_flag & MNT_RDONLY)
422 			return (EROFS);
423 		uid = vap->va_uid;
424 		if (uid == (uid_t)VNOVAL)
425 			uid = pmp->pm_uid;
426 		gid = vap->va_gid;
427 		if (gid == (gid_t)VNOVAL)
428 			gid = pmp->pm_gid;
429 		if ((cred->cr_uid != pmp->pm_uid || uid != pmp->pm_uid ||
430 		    (gid != pmp->pm_gid && !groupmember(gid, cred))) &&
431 		    (error = suser_cred(cred, PRISON_ROOT)))
432 			return error;
433 		if (uid != pmp->pm_uid || gid != pmp->pm_gid)
434 			return EINVAL;
435 	}
436 
437 	if (vap->va_size != VNOVAL) {
438 		/*
439 		 * Disallow write attempts on read-only filesystems;
440 		 * unless the file is a socket, fifo, or a block or
441 		 * character device resident on the filesystem.
442 		 */
443 		switch (vp->v_type) {
444 		case VDIR:
445 			return (EISDIR);
446 			/* NOT REACHED */
447 		case VLNK:
448 		case VREG:
449 			if (vp->v_mount->mnt_flag & MNT_RDONLY)
450 				return (EROFS);
451 			break;
452 		default:
453 			break;
454 		}
455 		error = detrunc(dep, vap->va_size, 0, cred, ap->a_td);
456 		if (error)
457 			return error;
458 	}
459 	if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
460 		if (vp->v_mount->mnt_flag & MNT_RDONLY)
461 			return (EROFS);
462 		if (cred->cr_uid != pmp->pm_uid &&
463 		    (error = suser_cred(cred, PRISON_ROOT)) &&
464 		    ((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
465 		    (error = VOP_ACCESS(ap->a_vp, VWRITE, cred, ap->a_td))))
466 			return (error);
467 		if (vp->v_type != VDIR) {
468 			if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95) == 0 &&
469 			    vap->va_atime.tv_sec != VNOVAL) {
470 				dep->de_flag &= ~DE_ACCESS;
471 				unix2dostime(&vap->va_atime, &dep->de_ADate,
472 				    NULL, NULL);
473 			}
474 			if (vap->va_mtime.tv_sec != VNOVAL) {
475 				dep->de_flag &= ~DE_UPDATE;
476 				unix2dostime(&vap->va_mtime, &dep->de_MDate,
477 				    &dep->de_MTime, NULL);
478 			}
479 			dep->de_Attributes |= ATTR_ARCHIVE;
480 			dep->de_flag |= DE_MODIFIED;
481 		}
482 	}
483 	/*
484 	 * DOS files only have the ability to have their writability
485 	 * attribute set, so we use the owner write bit to set the readonly
486 	 * attribute.
487 	 */
488 	if (vap->va_mode != (mode_t)VNOVAL) {
489 		if (vp->v_mount->mnt_flag & MNT_RDONLY)
490 			return (EROFS);
491 		if (cred->cr_uid != pmp->pm_uid &&
492 		    (error = suser_cred(cred, PRISON_ROOT)))
493 			return (error);
494 		if (vp->v_type != VDIR) {
495 			/* We ignore the read and execute bits. */
496 			if (vap->va_mode & VWRITE)
497 				dep->de_Attributes &= ~ATTR_READONLY;
498 			else
499 				dep->de_Attributes |= ATTR_READONLY;
500 			dep->de_Attributes |= ATTR_ARCHIVE;
501 			dep->de_flag |= DE_MODIFIED;
502 		}
503 	}
504 	return (deupdat(dep, 1));
505 }
506 
507 static int
508 msdosfs_read(ap)
509 	struct vop_read_args /* {
510 		struct vnode *a_vp;
511 		struct uio *a_uio;
512 		int a_ioflag;
513 		struct ucred *a_cred;
514 	} */ *ap;
515 {
516 	int error = 0;
517 	int blsize;
518 	int isadir;
519 	int orig_resid;
520 	u_int n;
521 	u_long diff;
522 	u_long on;
523 	daddr_t lbn;
524 	daddr_t rablock;
525 	int rasize;
526 	int seqcount;
527 	struct buf *bp;
528 	struct vnode *vp = ap->a_vp;
529 	struct denode *dep = VTODE(vp);
530 	struct msdosfsmount *pmp = dep->de_pmp;
531 	struct uio *uio = ap->a_uio;
532 
533 	if (uio->uio_offset < 0)
534 		return (EINVAL);
535 
536 	if ((uoff_t)uio->uio_offset > DOS_FILESIZE_MAX)
537 		return (0);
538 	/*
539 	 * If they didn't ask for any data, then we are done.
540 	 */
541 	orig_resid = uio->uio_resid;
542 	if (orig_resid <= 0)
543 		return (0);
544 
545 	seqcount = ap->a_ioflag >> IO_SEQSHIFT;
546 
547 	isadir = dep->de_Attributes & ATTR_DIRECTORY;
548 	do {
549 		if (uio->uio_offset >= dep->de_FileSize)
550 			break;
551 		lbn = de_cluster(pmp, uio->uio_offset);
552 		/*
553 		 * If we are operating on a directory file then be sure to
554 		 * do i/o with the vnode for the filesystem instead of the
555 		 * vnode for the directory.
556 		 */
557 		if (isadir) {
558 			/* convert cluster # to block # */
559 			error = pcbmap(dep, lbn, &lbn, 0, &blsize);
560 			if (error == E2BIG) {
561 				error = EINVAL;
562 				break;
563 			} else if (error)
564 				break;
565 			error = bread(pmp->pm_devvp, lbn, blsize, NOCRED, &bp);
566 		} else {
567 			blsize = pmp->pm_bpcluster;
568 			rablock = lbn + 1;
569 			if (seqcount > 1 &&
570 			    de_cn2off(pmp, rablock) < dep->de_FileSize) {
571 				rasize = pmp->pm_bpcluster;
572 				error = breadn(vp, lbn, blsize,
573 				    &rablock, &rasize, 1, NOCRED, &bp);
574 			} else {
575 				error = bread(vp, lbn, blsize, NOCRED, &bp);
576 			}
577 		}
578 		if (error) {
579 			brelse(bp);
580 			break;
581 		}
582 		on = uio->uio_offset & pmp->pm_crbomask;
583 		diff = pmp->pm_bpcluster - on;
584 		n = diff > uio->uio_resid ? uio->uio_resid : diff;
585 		diff = dep->de_FileSize - uio->uio_offset;
586 		if (diff < n)
587 			n = diff;
588 		diff = blsize - bp->b_resid;
589 		if (diff < n)
590 			n = diff;
591 		error = uiomove(bp->b_data + on, (int) n, uio);
592 		brelse(bp);
593 	} while (error == 0 && uio->uio_resid > 0 && n != 0);
594 	if (!isadir && (error == 0 || uio->uio_resid != orig_resid) &&
595 	    (vp->v_mount->mnt_flag & MNT_NOATIME) == 0)
596 		dep->de_flag |= DE_ACCESS;
597 	return (error);
598 }
599 
600 /*
601  * Write data to a file or directory.
602  */
603 static int
604 msdosfs_write(ap)
605 	struct vop_write_args /* {
606 		struct vnode *a_vp;
607 		struct uio *a_uio;
608 		int a_ioflag;
609 		struct ucred *a_cred;
610 	} */ *ap;
611 {
612 	int n;
613 	int croffset;
614 	int resid;
615 	u_long osize;
616 	int error = 0;
617 	u_long count;
618 	daddr_t bn, lastcn;
619 	struct buf *bp;
620 	int ioflag = ap->a_ioflag;
621 	struct uio *uio = ap->a_uio;
622 	struct thread *td = uio->uio_td;
623 	struct vnode *vp = ap->a_vp;
624 	struct vnode *thisvp;
625 	struct denode *dep = VTODE(vp);
626 	struct msdosfsmount *pmp = dep->de_pmp;
627 	struct ucred *cred = ap->a_cred;
628 
629 #ifdef MSDOSFS_DEBUG
630 	printf("msdosfs_write(vp %p, uio %p, ioflag %x, cred %p\n",
631 	    vp, uio, ioflag, cred);
632 	printf("msdosfs_write(): diroff %lu, dirclust %lu, startcluster %lu\n",
633 	    dep->de_diroffset, dep->de_dirclust, dep->de_StartCluster);
634 #endif
635 
636 	switch (vp->v_type) {
637 	case VREG:
638 		if (ioflag & IO_APPEND)
639 			uio->uio_offset = dep->de_FileSize;
640 		thisvp = vp;
641 		break;
642 	case VDIR:
643 		return EISDIR;
644 	default:
645 		panic("msdosfs_write(): bad file type");
646 	}
647 
648 	if (uio->uio_offset < 0)
649 		return (EFBIG);
650 
651 	if (uio->uio_resid == 0)
652 		return (0);
653 
654 	/*
655 	 * If they've exceeded their filesize limit, tell them about it.
656 	 */
657 	if (td != NULL) {
658 		PROC_LOCK(td->td_proc);
659 		if ((uoff_t)uio->uio_offset + uio->uio_resid >
660 		    lim_cur(td->td_proc, RLIMIT_FSIZE)) {
661 			psignal(td->td_proc, SIGXFSZ);
662 			PROC_UNLOCK(td->td_proc);
663 			return (EFBIG);
664 		}
665 		PROC_UNLOCK(td->td_proc);
666 	}
667 
668 	if ((uoff_t)uio->uio_offset + uio->uio_resid > DOS_FILESIZE_MAX)
669 		return (EFBIG);
670 
671 	/*
672 	 * If the offset we are starting the write at is beyond the end of
673 	 * the file, then they've done a seek.  Unix filesystems allow
674 	 * files with holes in them, DOS doesn't so we must fill the hole
675 	 * with zeroed blocks.
676 	 */
677 	if (uio->uio_offset > dep->de_FileSize) {
678 		error = deextend(dep, uio->uio_offset, cred);
679 		if (error)
680 			return (error);
681 	}
682 
683 	/*
684 	 * Remember some values in case the write fails.
685 	 */
686 	resid = uio->uio_resid;
687 	osize = dep->de_FileSize;
688 
689 	/*
690 	 * If we write beyond the end of the file, extend it to its ultimate
691 	 * size ahead of the time to hopefully get a contiguous area.
692 	 */
693 	if (uio->uio_offset + resid > osize) {
694 		count = de_clcount(pmp, uio->uio_offset + resid) -
695 			de_clcount(pmp, osize);
696 		error = extendfile(dep, count, NULL, NULL, 0);
697 		if (error &&  (error != ENOSPC || (ioflag & IO_UNIT)))
698 			goto errexit;
699 		lastcn = dep->de_fc[FC_LASTFC].fc_frcn;
700 	} else
701 		lastcn = de_clcount(pmp, osize) - 1;
702 
703 	do {
704 		if (de_cluster(pmp, uio->uio_offset) > lastcn) {
705 			error = ENOSPC;
706 			break;
707 		}
708 
709 		croffset = uio->uio_offset & pmp->pm_crbomask;
710 		n = min(uio->uio_resid, pmp->pm_bpcluster - croffset);
711 		if (uio->uio_offset + n > dep->de_FileSize) {
712 			dep->de_FileSize = uio->uio_offset + n;
713 			/* The object size needs to be set before buffer is allocated */
714 			vnode_pager_setsize(vp, dep->de_FileSize);
715 		}
716 
717 		bn = de_cluster(pmp, uio->uio_offset);
718 		if ((uio->uio_offset & pmp->pm_crbomask) == 0
719 		    && (de_cluster(pmp, uio->uio_offset + uio->uio_resid)
720 			> de_cluster(pmp, uio->uio_offset)
721 			|| uio->uio_offset + uio->uio_resid >= dep->de_FileSize)) {
722 			/*
723 			 * If either the whole cluster gets written,
724 			 * or we write the cluster from its start beyond EOF,
725 			 * then no need to read data from disk.
726 			 */
727 			bp = getblk(thisvp, bn, pmp->pm_bpcluster, 0, 0, 0);
728 			clrbuf(bp);
729 			/*
730 			 * Do the bmap now, since pcbmap needs buffers
731 			 * for the fat table. (see msdosfs_strategy)
732 			 */
733 			if (bp->b_blkno == bp->b_lblkno) {
734 				error = pcbmap(dep, bp->b_lblkno, &bn, 0, 0);
735 				if (error)
736 					bp->b_blkno = -1;
737 				else
738 					bp->b_blkno = bn;
739 			}
740 			if (bp->b_blkno == -1) {
741 				brelse(bp);
742 				if (!error)
743 					error = EIO;		/* XXX */
744 				break;
745 			}
746 		} else {
747 			/*
748 			 * The block we need to write into exists, so read it in.
749 			 */
750 			error = bread(thisvp, bn, pmp->pm_bpcluster, cred, &bp);
751 			if (error) {
752 				brelse(bp);
753 				break;
754 			}
755 		}
756 
757 		/*
758 		 * Should these vnode_pager_* functions be done on dir
759 		 * files?
760 		 */
761 
762 		/*
763 		 * Copy the data from user space into the buf header.
764 		 */
765 		error = uiomove(bp->b_data + croffset, n, uio);
766 		if (error) {
767 			brelse(bp);
768 			break;
769 		}
770 
771 		/*
772 		 * If they want this synchronous then write it and wait for
773 		 * it.  Otherwise, if on a cluster boundary write it
774 		 * asynchronously so we can move on to the next block
775 		 * without delay.  Otherwise do a delayed write because we
776 		 * may want to write somemore into the block later.
777 		 */
778 		if (ioflag & IO_SYNC)
779 			(void) bwrite(bp);
780 		else if (n + croffset == pmp->pm_bpcluster)
781 			bawrite(bp);
782 		else
783 			bdwrite(bp);
784 		dep->de_flag |= DE_UPDATE;
785 	} while (error == 0 && uio->uio_resid > 0);
786 
787 	/*
788 	 * If the write failed and they want us to, truncate the file back
789 	 * to the size it was before the write was attempted.
790 	 */
791 errexit:
792 	if (error) {
793 		if (ioflag & IO_UNIT) {
794 			detrunc(dep, osize, ioflag & IO_SYNC, NOCRED, NULL);
795 			uio->uio_offset -= resid - uio->uio_resid;
796 			uio->uio_resid = resid;
797 		} else {
798 			detrunc(dep, dep->de_FileSize, ioflag & IO_SYNC, NOCRED, NULL);
799 			if (uio->uio_resid != resid)
800 				error = 0;
801 		}
802 	} else if (ioflag & IO_SYNC)
803 		error = deupdat(dep, 1);
804 	return (error);
805 }
806 
807 /*
808  * Flush the blocks of a file to disk.
809  *
810  * This function is worthless for vnodes that represent directories. Maybe we
811  * could just do a sync if they try an fsync on a directory file.
812  */
813 static int
814 msdosfs_fsync(ap)
815 	struct vop_fsync_args /* {
816 		struct vnode *a_vp;
817 		struct ucred *a_cred;
818 		int a_waitfor;
819 		struct thread *a_td;
820 	} */ *ap;
821 {
822 	/*
823 	 * Flush our dirty buffers.
824 	 */
825 	vop_stdfsync(ap);
826 
827 	return (deupdat(VTODE(ap->a_vp), ap->a_waitfor == MNT_WAIT));
828 }
829 
830 static int
831 msdosfs_remove(ap)
832 	struct vop_remove_args /* {
833 		struct vnode *a_dvp;
834 		struct vnode *a_vp;
835 		struct componentname *a_cnp;
836 	} */ *ap;
837 {
838 	struct denode *dep = VTODE(ap->a_vp);
839 	struct denode *ddep = VTODE(ap->a_dvp);
840 	int error;
841 
842 	if (ap->a_vp->v_type == VDIR)
843 		error = EPERM;
844 	else
845 		error = removede(ddep, dep);
846 #ifdef MSDOSFS_DEBUG
847 	printf("msdosfs_remove(), dep %p, v_usecount %d\n", dep, ap->a_vp->v_usecount);
848 #endif
849 	return (error);
850 }
851 
852 /*
853  * DOS filesystems don't know what links are.
854  */
855 static int
856 msdosfs_link(ap)
857 	struct vop_link_args /* {
858 		struct vnode *a_tdvp;
859 		struct vnode *a_vp;
860 		struct componentname *a_cnp;
861 	} */ *ap;
862 {
863 	return (EOPNOTSUPP);
864 }
865 
866 /*
867  * Renames on files require moving the denode to a new hash queue since the
868  * denode's location is used to compute which hash queue to put the file
869  * in. Unless it is a rename in place.  For example "mv a b".
870  *
871  * What follows is the basic algorithm:
872  *
873  * if (file move) {
874  *	if (dest file exists) {
875  *		remove dest file
876  *	}
877  *	if (dest and src in same directory) {
878  *		rewrite name in existing directory slot
879  *	} else {
880  *		write new entry in dest directory
881  *		update offset and dirclust in denode
882  *		move denode to new hash chain
883  *		clear old directory entry
884  *	}
885  * } else {
886  *	directory move
887  *	if (dest directory exists) {
888  *		if (dest is not empty) {
889  *			return ENOTEMPTY
890  *		}
891  *		remove dest directory
892  *	}
893  *	if (dest and src in same directory) {
894  *		rewrite name in existing entry
895  *	} else {
896  *		be sure dest is not a child of src directory
897  *		write entry in dest directory
898  *		update "." and ".." in moved directory
899  *		clear old directory entry for moved directory
900  *	}
901  * }
902  *
903  * On entry:
904  *	source's parent directory is unlocked
905  *	source file or directory is unlocked
906  *	destination's parent directory is locked
907  *	destination file or directory is locked if it exists
908  *
909  * On exit:
910  *	all denodes should be released
911  */
912 static int
913 msdosfs_rename(ap)
914 	struct vop_rename_args /* {
915 		struct vnode *a_fdvp;
916 		struct vnode *a_fvp;
917 		struct componentname *a_fcnp;
918 		struct vnode *a_tdvp;
919 		struct vnode *a_tvp;
920 		struct componentname *a_tcnp;
921 	} */ *ap;
922 {
923 	struct vnode *tdvp = ap->a_tdvp;
924 	struct vnode *fvp = ap->a_fvp;
925 	struct vnode *fdvp = ap->a_fdvp;
926 	struct vnode *tvp = ap->a_tvp;
927 	struct componentname *tcnp = ap->a_tcnp;
928 	struct componentname *fcnp = ap->a_fcnp;
929 	struct thread *td = fcnp->cn_thread;
930 	struct denode *ip, *xp, *dp, *zp;
931 	u_char toname[11], oldname[11];
932 	u_long from_diroffset, to_diroffset;
933 	u_char to_count;
934 	int doingdirectory = 0, newparent = 0;
935 	int error;
936 	u_long cn;
937 	daddr_t bn;
938 	struct denode *fddep;	/* from file's parent directory	 */
939 	struct msdosfsmount *pmp;
940 	struct direntry *dotdotp;
941 	struct buf *bp;
942 
943 	fddep = VTODE(ap->a_fdvp);
944 	pmp = fddep->de_pmp;
945 
946 	pmp = VFSTOMSDOSFS(fdvp->v_mount);
947 
948 #ifdef DIAGNOSTIC
949 	if ((tcnp->cn_flags & HASBUF) == 0 ||
950 	    (fcnp->cn_flags & HASBUF) == 0)
951 		panic("msdosfs_rename: no name");
952 #endif
953 	/*
954 	 * Check for cross-device rename.
955 	 */
956 	if ((fvp->v_mount != tdvp->v_mount) ||
957 	    (tvp && (fvp->v_mount != tvp->v_mount))) {
958 		error = EXDEV;
959 abortit:
960 		if (tdvp == tvp)
961 			vrele(tdvp);
962 		else
963 			vput(tdvp);
964 		if (tvp)
965 			vput(tvp);
966 		vrele(fdvp);
967 		vrele(fvp);
968 		return (error);
969 	}
970 
971 	/*
972 	 * If source and dest are the same, do nothing.
973 	 */
974 	if (tvp == fvp) {
975 		error = 0;
976 		goto abortit;
977 	}
978 
979 	error = vn_lock(fvp, LK_EXCLUSIVE, td);
980 	if (error)
981 		goto abortit;
982 	dp = VTODE(fdvp);
983 	ip = VTODE(fvp);
984 
985 	/*
986 	 * Be sure we are not renaming ".", "..", or an alias of ".". This
987 	 * leads to a crippled directory tree.  It's pretty tough to do a
988 	 * "ls" or "pwd" with the "." directory entry missing, and "cd .."
989 	 * doesn't work if the ".." entry is missing.
990 	 */
991 	if (ip->de_Attributes & ATTR_DIRECTORY) {
992 		/*
993 		 * Avoid ".", "..", and aliases of "." for obvious reasons.
994 		 */
995 		if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
996 		    dp == ip ||
997 		    (fcnp->cn_flags & ISDOTDOT) ||
998 		    (tcnp->cn_flags & ISDOTDOT) ||
999 		    (ip->de_flag & DE_RENAME)) {
1000 			VOP_UNLOCK(fvp, 0, td);
1001 			error = EINVAL;
1002 			goto abortit;
1003 		}
1004 		ip->de_flag |= DE_RENAME;
1005 		doingdirectory++;
1006 	}
1007 
1008 	/*
1009 	 * When the target exists, both the directory
1010 	 * and target vnodes are returned locked.
1011 	 */
1012 	dp = VTODE(tdvp);
1013 	xp = tvp ? VTODE(tvp) : NULL;
1014 	/*
1015 	 * Remember direntry place to use for destination
1016 	 */
1017 	to_diroffset = dp->de_fndoffset;
1018 	to_count = dp->de_fndcnt;
1019 
1020 	/*
1021 	 * If ".." must be changed (ie the directory gets a new
1022 	 * parent) then the source directory must not be in the
1023 	 * directory heirarchy above the target, as this would
1024 	 * orphan everything below the source directory. Also
1025 	 * the user must have write permission in the source so
1026 	 * as to be able to change "..". We must repeat the call
1027 	 * to namei, as the parent directory is unlocked by the
1028 	 * call to doscheckpath().
1029 	 */
1030 	error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_thread);
1031 	VOP_UNLOCK(fvp, 0, td);
1032 	if (VTODE(fdvp)->de_StartCluster != VTODE(tdvp)->de_StartCluster)
1033 		newparent = 1;
1034 	if (doingdirectory && newparent) {
1035 		if (error)	/* write access check above */
1036 			goto bad;
1037 		if (xp != NULL)
1038 			vput(tvp);
1039 		/*
1040 		 * doscheckpath() vput()'s dp,
1041 		 * so we have to do a relookup afterwards
1042 		 */
1043 		error = doscheckpath(ip, dp);
1044 		if (error)
1045 			goto out;
1046 		if ((tcnp->cn_flags & SAVESTART) == 0)
1047 			panic("msdosfs_rename: lost to startdir");
1048 		error = relookup(tdvp, &tvp, tcnp);
1049 		if (error)
1050 			goto out;
1051 		dp = VTODE(tdvp);
1052 		xp = tvp ? VTODE(tvp) : NULL;
1053 	}
1054 
1055 	if (xp != NULL) {
1056 		/*
1057 		 * Target must be empty if a directory and have no links
1058 		 * to it. Also, ensure source and target are compatible
1059 		 * (both directories, or both not directories).
1060 		 */
1061 		if (xp->de_Attributes & ATTR_DIRECTORY) {
1062 			if (!dosdirempty(xp)) {
1063 				error = ENOTEMPTY;
1064 				goto bad;
1065 			}
1066 			if (!doingdirectory) {
1067 				error = ENOTDIR;
1068 				goto bad;
1069 			}
1070 			cache_purge(tdvp);
1071 		} else if (doingdirectory) {
1072 			error = EISDIR;
1073 			goto bad;
1074 		}
1075 		error = removede(dp, xp);
1076 		if (error)
1077 			goto bad;
1078 		vput(tvp);
1079 		xp = NULL;
1080 	}
1081 
1082 	/*
1083 	 * Convert the filename in tcnp into a dos filename. We copy this
1084 	 * into the denode and directory entry for the destination
1085 	 * file/directory.
1086 	 */
1087 	error = uniqdosname(VTODE(tdvp), tcnp, toname);
1088 	if (error)
1089 		goto abortit;
1090 
1091 	/*
1092 	 * Since from wasn't locked at various places above,
1093 	 * have to do a relookup here.
1094 	 */
1095 	fcnp->cn_flags &= ~MODMASK;
1096 	fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
1097 	if ((fcnp->cn_flags & SAVESTART) == 0)
1098 		panic("msdosfs_rename: lost from startdir");
1099 	if (!newparent)
1100 		VOP_UNLOCK(tdvp, 0, td);
1101 	if (relookup(fdvp, &fvp, fcnp) == 0)
1102 		vrele(fdvp);
1103 	if (fvp == NULL) {
1104 		/*
1105 		 * From name has disappeared.
1106 		 */
1107 		if (doingdirectory)
1108 			panic("rename: lost dir entry");
1109 		vrele(ap->a_fvp);
1110 		if (newparent)
1111 			VOP_UNLOCK(tdvp, 0, td);
1112 		vrele(tdvp);
1113 		return 0;
1114 	}
1115 	xp = VTODE(fvp);
1116 	zp = VTODE(fdvp);
1117 	from_diroffset = zp->de_fndoffset;
1118 
1119 	/*
1120 	 * Ensure that the directory entry still exists and has not
1121 	 * changed till now. If the source is a file the entry may
1122 	 * have been unlinked or renamed. In either case there is
1123 	 * no further work to be done. If the source is a directory
1124 	 * then it cannot have been rmdir'ed or renamed; this is
1125 	 * prohibited by the DE_RENAME flag.
1126 	 */
1127 	if (xp != ip) {
1128 		if (doingdirectory)
1129 			panic("rename: lost dir entry");
1130 		vrele(ap->a_fvp);
1131 		VOP_UNLOCK(fvp, 0, td);
1132 		if (newparent)
1133 			VOP_UNLOCK(fdvp, 0, td);
1134 		xp = NULL;
1135 	} else {
1136 		vrele(fvp);
1137 		xp = NULL;
1138 
1139 		/*
1140 		 * First write a new entry in the destination
1141 		 * directory and mark the entry in the source directory
1142 		 * as deleted.  Then move the denode to the correct hash
1143 		 * chain for its new location in the filesystem.  And, if
1144 		 * we moved a directory, then update its .. entry to point
1145 		 * to the new parent directory.
1146 		 */
1147 		bcopy(ip->de_Name, oldname, 11);
1148 		bcopy(toname, ip->de_Name, 11);	/* update denode */
1149 		dp->de_fndoffset = to_diroffset;
1150 		dp->de_fndcnt = to_count;
1151 		error = createde(ip, dp, (struct denode **)0, tcnp);
1152 		if (error) {
1153 			bcopy(oldname, ip->de_Name, 11);
1154 			if (newparent)
1155 				VOP_UNLOCK(fdvp, 0, td);
1156 			VOP_UNLOCK(fvp, 0, td);
1157 			goto bad;
1158 		}
1159 		ip->de_refcnt++;
1160 		zp->de_fndoffset = from_diroffset;
1161 		error = removede(zp, ip);
1162 		if (error) {
1163 			/* XXX should really panic here, fs is corrupt */
1164 			if (newparent)
1165 				VOP_UNLOCK(fdvp, 0, td);
1166 			VOP_UNLOCK(fvp, 0, td);
1167 			goto bad;
1168 		}
1169 		if (!doingdirectory) {
1170 			error = pcbmap(dp, de_cluster(pmp, to_diroffset), 0,
1171 				       &ip->de_dirclust, 0);
1172 			if (error) {
1173 				/* XXX should really panic here, fs is corrupt */
1174 				if (newparent)
1175 					VOP_UNLOCK(fdvp, 0, td);
1176 				VOP_UNLOCK(fvp, 0, td);
1177 				goto bad;
1178 			}
1179 			if (ip->de_dirclust == MSDOSFSROOT)
1180 				ip->de_diroffset = to_diroffset;
1181 			else
1182 				ip->de_diroffset = to_diroffset & pmp->pm_crbomask;
1183 		}
1184 		reinsert(ip);
1185 		if (newparent)
1186 			VOP_UNLOCK(fdvp, 0, td);
1187 	}
1188 
1189 	/*
1190 	 * If we moved a directory to a new parent directory, then we must
1191 	 * fixup the ".." entry in the moved directory.
1192 	 */
1193 	if (doingdirectory && newparent) {
1194 		cn = ip->de_StartCluster;
1195 		if (cn == MSDOSFSROOT) {
1196 			/* this should never happen */
1197 			panic("msdosfs_rename(): updating .. in root directory?");
1198 		} else
1199 			bn = cntobn(pmp, cn);
1200 		error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
1201 			      NOCRED, &bp);
1202 		if (error) {
1203 			/* XXX should really panic here, fs is corrupt */
1204 			brelse(bp);
1205 			VOP_UNLOCK(fvp, 0, td);
1206 			goto bad;
1207 		}
1208 		dotdotp = (struct direntry *)bp->b_data + 1;
1209 		putushort(dotdotp->deStartCluster, dp->de_StartCluster);
1210 		if (FAT32(pmp))
1211 			putushort(dotdotp->deHighClust, dp->de_StartCluster >> 16);
1212 		error = bwrite(bp);
1213 		if (error) {
1214 			/* XXX should really panic here, fs is corrupt */
1215 			VOP_UNLOCK(fvp, 0, td);
1216 			goto bad;
1217 		}
1218 	}
1219 
1220 	VOP_UNLOCK(fvp, 0, td);
1221 bad:
1222 	if (xp)
1223 		vput(tvp);
1224 	vput(tdvp);
1225 out:
1226 	ip->de_flag &= ~DE_RENAME;
1227 	vrele(fdvp);
1228 	vrele(fvp);
1229 	return (error);
1230 
1231 }
1232 
1233 static struct {
1234 	struct direntry dot;
1235 	struct direntry dotdot;
1236 } dosdirtemplate = {
1237 	{	".       ", "   ",			/* the . entry */
1238 		ATTR_DIRECTORY,				/* file attribute */
1239 		0,					/* reserved */
1240 		0, { 0, 0 }, { 0, 0 },			/* create time & date */
1241 		{ 0, 0 },				/* access date */
1242 		{ 0, 0 },				/* high bits of start cluster */
1243 		{ 210, 4 }, { 210, 4 },			/* modify time & date */
1244 		{ 0, 0 },				/* startcluster */
1245 		{ 0, 0, 0, 0 }				/* filesize */
1246 	},
1247 	{	"..      ", "   ",			/* the .. entry */
1248 		ATTR_DIRECTORY,				/* file attribute */
1249 		0,					/* reserved */
1250 		0, { 0, 0 }, { 0, 0 },			/* create time & date */
1251 		{ 0, 0 },				/* access date */
1252 		{ 0, 0 },				/* high bits of start cluster */
1253 		{ 210, 4 }, { 210, 4 },			/* modify time & date */
1254 		{ 0, 0 },				/* startcluster */
1255 		{ 0, 0, 0, 0 }				/* filesize */
1256 	}
1257 };
1258 
1259 static int
1260 msdosfs_mkdir(ap)
1261 	struct vop_mkdir_args /* {
1262 		struct vnode *a_dvp;
1263 		struvt vnode **a_vpp;
1264 		struvt componentname *a_cnp;
1265 		struct vattr *a_vap;
1266 	} */ *ap;
1267 {
1268 	struct componentname *cnp = ap->a_cnp;
1269 	struct denode *dep;
1270 	struct denode *pdep = VTODE(ap->a_dvp);
1271 	struct direntry *denp;
1272 	struct msdosfsmount *pmp = pdep->de_pmp;
1273 	struct buf *bp;
1274 	u_long newcluster, pcl;
1275 	int bn;
1276 	int error;
1277 	struct denode ndirent;
1278 	struct timespec ts;
1279 
1280 	/*
1281 	 * If this is the root directory and there is no space left we
1282 	 * can't do anything.  This is because the root directory can not
1283 	 * change size.
1284 	 */
1285 	if (pdep->de_StartCluster == MSDOSFSROOT
1286 	    && pdep->de_fndoffset >= pdep->de_FileSize) {
1287 		error = ENOSPC;
1288 		goto bad2;
1289 	}
1290 
1291 	/*
1292 	 * Allocate a cluster to hold the about to be created directory.
1293 	 */
1294 	error = clusteralloc(pmp, 0, 1, CLUST_EOFE, &newcluster, NULL);
1295 	if (error)
1296 		goto bad2;
1297 
1298 	bzero(&ndirent, sizeof(ndirent));
1299 	ndirent.de_pmp = pmp;
1300 	ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE;
1301 	getnanotime(&ts);
1302 	DETIMES(&ndirent, &ts, &ts, &ts);
1303 
1304 	/*
1305 	 * Now fill the cluster with the "." and ".." entries. And write
1306 	 * the cluster to disk.  This way it is there for the parent
1307 	 * directory to be pointing at if there were a crash.
1308 	 */
1309 	bn = cntobn(pmp, newcluster);
1310 	/* always succeeds */
1311 	bp = getblk(pmp->pm_devvp, bn, pmp->pm_bpcluster, 0, 0, 0);
1312 	bzero(bp->b_data, pmp->pm_bpcluster);
1313 	bcopy(&dosdirtemplate, bp->b_data, sizeof dosdirtemplate);
1314 	denp = (struct direntry *)bp->b_data;
1315 	putushort(denp[0].deStartCluster, newcluster);
1316 	putushort(denp[0].deCDate, ndirent.de_CDate);
1317 	putushort(denp[0].deCTime, ndirent.de_CTime);
1318 	denp[0].deCHundredth = ndirent.de_CHun;
1319 	putushort(denp[0].deADate, ndirent.de_ADate);
1320 	putushort(denp[0].deMDate, ndirent.de_MDate);
1321 	putushort(denp[0].deMTime, ndirent.de_MTime);
1322 	pcl = pdep->de_StartCluster;
1323 	if (FAT32(pmp) && pcl == pmp->pm_rootdirblk)
1324 		pcl = 0;
1325 	putushort(denp[1].deStartCluster, pcl);
1326 	putushort(denp[1].deCDate, ndirent.de_CDate);
1327 	putushort(denp[1].deCTime, ndirent.de_CTime);
1328 	denp[1].deCHundredth = ndirent.de_CHun;
1329 	putushort(denp[1].deADate, ndirent.de_ADate);
1330 	putushort(denp[1].deMDate, ndirent.de_MDate);
1331 	putushort(denp[1].deMTime, ndirent.de_MTime);
1332 	if (FAT32(pmp)) {
1333 		putushort(denp[0].deHighClust, newcluster >> 16);
1334 		putushort(denp[1].deHighClust, pdep->de_StartCluster >> 16);
1335 	}
1336 
1337 	error = bwrite(bp);
1338 	if (error)
1339 		goto bad;
1340 
1341 	/*
1342 	 * Now build up a directory entry pointing to the newly allocated
1343 	 * cluster.  This will be written to an empty slot in the parent
1344 	 * directory.
1345 	 */
1346 #ifdef DIAGNOSTIC
1347 	if ((cnp->cn_flags & HASBUF) == 0)
1348 		panic("msdosfs_mkdir: no name");
1349 #endif
1350 	error = uniqdosname(pdep, cnp, ndirent.de_Name);
1351 	if (error)
1352 		goto bad;
1353 
1354 	ndirent.de_Attributes = ATTR_DIRECTORY;
1355 	ndirent.de_LowerCase = 0;
1356 	ndirent.de_StartCluster = newcluster;
1357 	ndirent.de_FileSize = 0;
1358 	ndirent.de_dev = pdep->de_dev;
1359 	ndirent.de_devvp = pdep->de_devvp;
1360 	error = createde(&ndirent, pdep, &dep, cnp);
1361 	if (error)
1362 		goto bad;
1363 	*ap->a_vpp = DETOV(dep);
1364 	return (0);
1365 
1366 bad:
1367 	clusterfree(pmp, newcluster, NULL);
1368 bad2:
1369 	return (error);
1370 }
1371 
1372 static int
1373 msdosfs_rmdir(ap)
1374 	struct vop_rmdir_args /* {
1375 		struct vnode *a_dvp;
1376 		struct vnode *a_vp;
1377 		struct componentname *a_cnp;
1378 	} */ *ap;
1379 {
1380 	struct vnode *vp = ap->a_vp;
1381 	struct vnode *dvp = ap->a_dvp;
1382 	struct componentname *cnp = ap->a_cnp;
1383 	struct denode *ip, *dp;
1384 	struct thread *td = cnp->cn_thread;
1385 	int error;
1386 
1387 	ip = VTODE(vp);
1388 	dp = VTODE(dvp);
1389 
1390 	/*
1391 	 * Verify the directory is empty (and valid).
1392 	 * (Rmdir ".." won't be valid since
1393 	 *  ".." will contain a reference to
1394 	 *  the current directory and thus be
1395 	 *  non-empty.)
1396 	 */
1397 	error = 0;
1398 	if (!dosdirempty(ip) || ip->de_flag & DE_RENAME) {
1399 		error = ENOTEMPTY;
1400 		goto out;
1401 	}
1402 	/*
1403 	 * Delete the entry from the directory.  For dos filesystems this
1404 	 * gets rid of the directory entry on disk, the in memory copy
1405 	 * still exists but the de_refcnt is <= 0.  This prevents it from
1406 	 * being found by deget().  When the vput() on dep is done we give
1407 	 * up access and eventually msdosfs_reclaim() will be called which
1408 	 * will remove it from the denode cache.
1409 	 */
1410 	error = removede(dp, ip);
1411 	if (error)
1412 		goto out;
1413 	/*
1414 	 * This is where we decrement the link count in the parent
1415 	 * directory.  Since dos filesystems don't do this we just purge
1416 	 * the name cache.
1417 	 */
1418 	cache_purge(dvp);
1419 	VOP_UNLOCK(dvp, 0, td);
1420 	/*
1421 	 * Truncate the directory that is being deleted.
1422 	 */
1423 	error = detrunc(ip, (u_long)0, IO_SYNC, cnp->cn_cred, td);
1424 	cache_purge(vp);
1425 
1426 	vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, td);
1427 out:
1428 	return (error);
1429 }
1430 
1431 /*
1432  * DOS filesystems don't know what symlinks are.
1433  */
1434 static int
1435 msdosfs_symlink(ap)
1436 	struct vop_symlink_args /* {
1437 		struct vnode *a_dvp;
1438 		struct vnode **a_vpp;
1439 		struct componentname *a_cnp;
1440 		struct vattr *a_vap;
1441 		char *a_target;
1442 	} */ *ap;
1443 {
1444 	return (EOPNOTSUPP);
1445 }
1446 
1447 static int
1448 msdosfs_readdir(ap)
1449 	struct vop_readdir_args /* {
1450 		struct vnode *a_vp;
1451 		struct uio *a_uio;
1452 		struct ucred *a_cred;
1453 		int *a_eofflag;
1454 		int *a_ncookies;
1455 		u_long **a_cookies;
1456 	} */ *ap;
1457 {
1458 	int error = 0;
1459 	int diff;
1460 	long n;
1461 	int blsize;
1462 	long on;
1463 	u_long cn;
1464 	uint64_t fileno;
1465 	u_long dirsperblk;
1466 	long bias = 0;
1467 	daddr_t bn, lbn;
1468 	struct buf *bp;
1469 	struct denode *dep = VTODE(ap->a_vp);
1470 	struct msdosfsmount *pmp = dep->de_pmp;
1471 	struct direntry *dentp;
1472 	struct dirent dirbuf;
1473 	struct uio *uio = ap->a_uio;
1474 	u_long *cookies = NULL;
1475 	int ncookies = 0;
1476 	off_t offset, off;
1477 	int chksum = -1;
1478 
1479 #ifdef MSDOSFS_DEBUG
1480 	printf("msdosfs_readdir(): vp %p, uio %p, cred %p, eofflagp %p\n",
1481 	    ap->a_vp, uio, ap->a_cred, ap->a_eofflag);
1482 #endif
1483 
1484 	/*
1485 	 * msdosfs_readdir() won't operate properly on regular files since
1486 	 * it does i/o only with the the filesystem vnode, and hence can
1487 	 * retrieve the wrong block from the buffer cache for a plain file.
1488 	 * So, fail attempts to readdir() on a plain file.
1489 	 */
1490 	if ((dep->de_Attributes & ATTR_DIRECTORY) == 0)
1491 		return (ENOTDIR);
1492 
1493 	/*
1494 	 * To be safe, initialize dirbuf
1495 	 */
1496 	bzero(dirbuf.d_name, sizeof(dirbuf.d_name));
1497 
1498 	/*
1499 	 * If the user buffer is smaller than the size of one dos directory
1500 	 * entry or the file offset is not a multiple of the size of a
1501 	 * directory entry, then we fail the read.
1502 	 */
1503 	off = offset = uio->uio_offset;
1504 	if (uio->uio_resid < sizeof(struct direntry) ||
1505 	    (offset & (sizeof(struct direntry) - 1)))
1506 		return (EINVAL);
1507 
1508 	if (ap->a_ncookies) {
1509 		ncookies = uio->uio_resid / 16;
1510 		MALLOC(cookies, u_long *, ncookies * sizeof(u_long), M_TEMP,
1511 		       M_WAITOK);
1512 		*ap->a_cookies = cookies;
1513 		*ap->a_ncookies = ncookies;
1514 	}
1515 
1516 	dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry);
1517 
1518 	/*
1519 	 * If they are reading from the root directory then, we simulate
1520 	 * the . and .. entries since these don't exist in the root
1521 	 * directory.  We also set the offset bias to make up for having to
1522 	 * simulate these entries. By this I mean that at file offset 64 we
1523 	 * read the first entry in the root directory that lives on disk.
1524 	 */
1525 	if (dep->de_StartCluster == MSDOSFSROOT
1526 	    || (FAT32(pmp) && dep->de_StartCluster == pmp->pm_rootdirblk)) {
1527 #if 0
1528 		printf("msdosfs_readdir(): going after . or .. in root dir, offset %d\n",
1529 		    offset);
1530 #endif
1531 		bias = 2 * sizeof(struct direntry);
1532 		if (offset < bias) {
1533 			for (n = (int)offset / sizeof(struct direntry);
1534 			     n < 2; n++) {
1535 				if (FAT32(pmp))
1536 					fileno = (uint64_t)cntobn(pmp,
1537 								 pmp->pm_rootdirblk)
1538 							  * dirsperblk;
1539 				else
1540 					fileno = 1;
1541 #ifdef MSDOSFS_LARGE
1542 				dirbuf.d_fileno = msdosfs_fileno_map(
1543 				    pmp->pm_mountp, fileno);
1544 #else
1545 				dirbuf.d_fileno = (uint32_t)fileno;
1546 #endif
1547 				dirbuf.d_type = DT_DIR;
1548 				switch (n) {
1549 				case 0:
1550 					dirbuf.d_namlen = 1;
1551 					strcpy(dirbuf.d_name, ".");
1552 					break;
1553 				case 1:
1554 					dirbuf.d_namlen = 2;
1555 					strcpy(dirbuf.d_name, "..");
1556 					break;
1557 				}
1558 				dirbuf.d_reclen = GENERIC_DIRSIZ(&dirbuf);
1559 				if (uio->uio_resid < dirbuf.d_reclen)
1560 					goto out;
1561 				error = uiomove(&dirbuf, dirbuf.d_reclen, uio);
1562 				if (error)
1563 					goto out;
1564 				offset += sizeof(struct direntry);
1565 				off = offset;
1566 				if (cookies) {
1567 					*cookies++ = offset;
1568 					if (--ncookies <= 0)
1569 						goto out;
1570 				}
1571 			}
1572 		}
1573 	}
1574 
1575 	mbnambuf_init();
1576 	off = offset;
1577 	while (uio->uio_resid > 0) {
1578 		lbn = de_cluster(pmp, offset - bias);
1579 		on = (offset - bias) & pmp->pm_crbomask;
1580 		n = min(pmp->pm_bpcluster - on, uio->uio_resid);
1581 		diff = dep->de_FileSize - (offset - bias);
1582 		if (diff <= 0)
1583 			break;
1584 		n = min(n, diff);
1585 		error = pcbmap(dep, lbn, &bn, &cn, &blsize);
1586 		if (error)
1587 			break;
1588 		error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp);
1589 		if (error) {
1590 			brelse(bp);
1591 			return (error);
1592 		}
1593 		n = min(n, blsize - bp->b_resid);
1594 		if (n == 0) {
1595 			brelse(bp);
1596 			return (EIO);
1597 		}
1598 
1599 		/*
1600 		 * Convert from dos directory entries to fs-independent
1601 		 * directory entries.
1602 		 */
1603 		for (dentp = (struct direntry *)(bp->b_data + on);
1604 		     (char *)dentp < bp->b_data + on + n;
1605 		     dentp++, offset += sizeof(struct direntry)) {
1606 #if 0
1607 			printf("rd: dentp %08x prev %08x crnt %08x deName %02x attr %02x\n",
1608 			    dentp, prev, crnt, dentp->deName[0], dentp->deAttributes);
1609 #endif
1610 			/*
1611 			 * If this is an unused entry, we can stop.
1612 			 */
1613 			if (dentp->deName[0] == SLOT_EMPTY) {
1614 				brelse(bp);
1615 				goto out;
1616 			}
1617 			/*
1618 			 * Skip deleted entries.
1619 			 */
1620 			if (dentp->deName[0] == SLOT_DELETED) {
1621 				chksum = -1;
1622 				mbnambuf_init();
1623 				continue;
1624 			}
1625 
1626 			/*
1627 			 * Handle Win95 long directory entries
1628 			 */
1629 			if (dentp->deAttributes == ATTR_WIN95) {
1630 				if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
1631 					continue;
1632 				chksum = win2unixfn((struct winentry *)dentp,
1633 					chksum, pmp);
1634 				continue;
1635 			}
1636 
1637 			/*
1638 			 * Skip volume labels
1639 			 */
1640 			if (dentp->deAttributes & ATTR_VOLUME) {
1641 				chksum = -1;
1642 				mbnambuf_init();
1643 				continue;
1644 			}
1645 			/*
1646 			 * This computation of d_fileno must match
1647 			 * the computation of va_fileid in
1648 			 * msdosfs_getattr.
1649 			 */
1650 			if (dentp->deAttributes & ATTR_DIRECTORY) {
1651 				fileno = getushort(dentp->deStartCluster);
1652 				if (FAT32(pmp))
1653 					fileno |= getushort(dentp->deHighClust) << 16;
1654 				/* if this is the root directory */
1655 				if (fileno == MSDOSFSROOT)
1656 					if (FAT32(pmp))
1657 						fileno = (uint64_t)cntobn(pmp,
1658 								pmp->pm_rootdirblk)
1659 							 * dirsperblk;
1660 					else
1661 						fileno = 1;
1662 				else
1663 					fileno = (uint64_t)cntobn(pmp, fileno) *
1664 					    dirsperblk;
1665 				dirbuf.d_type = DT_DIR;
1666 			} else {
1667 				fileno = (uint64_t)offset / sizeof(struct direntry);
1668 				dirbuf.d_type = DT_REG;
1669 			}
1670 #ifdef MSDOSFS_LARGE
1671 			dirbuf.d_fileno = msdosfs_fileno_map(pmp->pm_mountp,
1672 			    fileno);
1673 #else
1674 			dirbuf.d_fileno = (uint32_t)fileno;
1675 #endif
1676 			if (chksum != winChksum(dentp->deName)) {
1677 				dirbuf.d_namlen = dos2unixfn(dentp->deName,
1678 				    (u_char *)dirbuf.d_name,
1679 				    dentp->deLowerCase |
1680 					((pmp->pm_flags & MSDOSFSMNT_SHORTNAME) ?
1681 					(LCASE_BASE | LCASE_EXT) : 0),
1682 				    pmp);
1683 				mbnambuf_init();
1684 			} else
1685 				mbnambuf_flush(&dirbuf);
1686 			chksum = -1;
1687 			dirbuf.d_reclen = GENERIC_DIRSIZ(&dirbuf);
1688 			if (uio->uio_resid < dirbuf.d_reclen) {
1689 				brelse(bp);
1690 				goto out;
1691 			}
1692 			error = uiomove(&dirbuf, dirbuf.d_reclen, uio);
1693 			if (error) {
1694 				brelse(bp);
1695 				goto out;
1696 			}
1697 			if (cookies) {
1698 				*cookies++ = offset + sizeof(struct direntry);
1699 				if (--ncookies <= 0) {
1700 					brelse(bp);
1701 					goto out;
1702 				}
1703 			}
1704 			off = offset + sizeof(struct direntry);
1705 		}
1706 		brelse(bp);
1707 	}
1708 out:
1709 	/* Subtract unused cookies */
1710 	if (ap->a_ncookies)
1711 		*ap->a_ncookies -= ncookies;
1712 
1713 	uio->uio_offset = off;
1714 
1715 	/*
1716 	 * Set the eofflag (NFS uses it)
1717 	 */
1718 	if (ap->a_eofflag) {
1719 		if (dep->de_FileSize - (offset - bias) <= 0)
1720 			*ap->a_eofflag = 1;
1721 		else
1722 			*ap->a_eofflag = 0;
1723 	}
1724 	return (error);
1725 }
1726 
1727 /*
1728  * vp  - address of vnode file the file
1729  * bn  - which cluster we are interested in mapping to a filesystem block number.
1730  * vpp - returns the vnode for the block special file holding the filesystem
1731  *	 containing the file of interest
1732  * bnp - address of where to return the filesystem relative block number
1733  */
1734 static int
1735 msdosfs_bmap(ap)
1736 	struct vop_bmap_args /* {
1737 		struct vnode *a_vp;
1738 		daddr_t a_bn;
1739 		struct vnode **a_vpp;
1740 		daddr_t *a_bnp;
1741 		int *a_runp;
1742 		int *a_runb;
1743 	} */ *ap;
1744 {
1745 	struct denode *dep = VTODE(ap->a_vp);
1746 	daddr_t blkno;
1747 	int error;
1748 
1749 	if (ap->a_vpp != NULL)
1750 		*ap->a_vpp = dep->de_devvp;
1751 	if (ap->a_bnp == NULL)
1752 		return (0);
1753 	if (ap->a_runp) {
1754 		/*
1755 		 * Sequential clusters should be counted here.
1756 		 */
1757 		*ap->a_runp = 0;
1758 	}
1759 	if (ap->a_runb) {
1760 		*ap->a_runb = 0;
1761 	}
1762 	error = pcbmap(dep, ap->a_bn, &blkno, 0, 0);
1763 	*ap->a_bnp = blkno;
1764 	return (error);
1765 }
1766 
1767 static int
1768 msdosfs_strategy(ap)
1769 	struct vop_strategy_args /* {
1770 		struct vnode *a_vp;
1771 		struct buf *a_bp;
1772 	} */ *ap;
1773 {
1774 	struct buf *bp = ap->a_bp;
1775 	struct denode *dep = VTODE(bp->b_vp);
1776 	struct vnode *vp;
1777 	int error = 0;
1778 	daddr_t blkno;
1779 
1780 	KASSERT(ap->a_vp == ap->a_bp->b_vp, ("%s(%p != %p)",
1781 	    __func__, ap->a_vp, ap->a_bp->b_vp));
1782 	if (bp->b_vp->v_type == VBLK || bp->b_vp->v_type == VCHR)
1783 		panic("msdosfs_strategy: spec");
1784 	/*
1785 	 * If we don't already know the filesystem relative block number
1786 	 * then get it using pcbmap().  If pcbmap() returns the block
1787 	 * number as -1 then we've got a hole in the file.  DOS filesystems
1788 	 * don't allow files with holes, so we shouldn't ever see this.
1789 	 */
1790 	if (bp->b_blkno == bp->b_lblkno) {
1791 		error = pcbmap(dep, bp->b_lblkno, &blkno, 0, 0);
1792 		bp->b_blkno = blkno;
1793 		if (error) {
1794 			bp->b_error = error;
1795 			bp->b_ioflags |= BIO_ERROR;
1796 			bufdone(bp);
1797 			return (error);
1798 		}
1799 		if ((long)bp->b_blkno == -1)
1800 			vfs_bio_clrbuf(bp);
1801 	}
1802 	if (bp->b_blkno == -1) {
1803 		bufdone(bp);
1804 		return (0);
1805 	}
1806 	/*
1807 	 * Read/write the block from/to the disk that contains the desired
1808 	 * file block.
1809 	 */
1810 	vp = dep->de_devvp;
1811 	bp->b_dev = vp->v_rdev;
1812 	bp->b_iooffset = dbtob(bp->b_blkno);
1813 	VOP_SPECSTRATEGY(vp, bp);
1814 	return (0);
1815 }
1816 
1817 static int
1818 msdosfs_print(ap)
1819 	struct vop_print_args /* {
1820 		struct vnode *vp;
1821 	} */ *ap;
1822 {
1823 	struct denode *dep = VTODE(ap->a_vp);
1824 
1825 	printf("\tstartcluster %lu, dircluster %lu, diroffset %lu, ",
1826 	       dep->de_StartCluster, dep->de_dirclust, dep->de_diroffset);
1827 	printf("on dev (%d, %d)\n", major(dep->de_dev), minor(dep->de_dev));
1828 	return (0);
1829 }
1830 
1831 static int
1832 msdosfs_pathconf(ap)
1833 	struct vop_pathconf_args /* {
1834 		struct vnode *a_vp;
1835 		int a_name;
1836 		int *a_retval;
1837 	} */ *ap;
1838 {
1839 	struct msdosfsmount *pmp = VTODE(ap->a_vp)->de_pmp;
1840 
1841 	switch (ap->a_name) {
1842 	case _PC_LINK_MAX:
1843 		*ap->a_retval = 1;
1844 		return (0);
1845 	case _PC_NAME_MAX:
1846 		*ap->a_retval = pmp->pm_flags & MSDOSFSMNT_LONGNAME ? WIN_MAXLEN : 12;
1847 		return (0);
1848 	case _PC_PATH_MAX:
1849 		*ap->a_retval = PATH_MAX;
1850 		return (0);
1851 	case _PC_CHOWN_RESTRICTED:
1852 		*ap->a_retval = 1;
1853 		return (0);
1854 	case _PC_NO_TRUNC:
1855 		*ap->a_retval = 0;
1856 		return (0);
1857 	default:
1858 		return (EINVAL);
1859 	}
1860 	/* NOTREACHED */
1861 }
1862 
1863 static int
1864 msdosfs_advlock(ap)
1865 	struct vop_advlock_args /* {
1866 		struct vnode *a_vp;
1867 		u_char a_id;
1868 		int a_op;
1869 		struct flock *a_fl;
1870 		int a_flags;
1871 	} */ *ap;
1872 {
1873 	struct denode *dep = VTODE(ap->a_vp);
1874 
1875 	return (lf_advlock(ap, &dep->de_lockf, dep->de_FileSize));
1876 }
1877 
1878 /* Global vfs data structures for msdosfs */
1879 vop_t **msdosfs_vnodeop_p;
1880 static struct vnodeopv_entry_desc msdosfs_vnodeop_entries[] = {
1881 	{ &vop_default_desc,		(vop_t *) vop_defaultop },
1882 	{ &vop_access_desc,		(vop_t *) msdosfs_access },
1883 	{ &vop_advlock_desc,            (vop_t *) msdosfs_advlock },
1884 	{ &vop_bmap_desc,		(vop_t *) msdosfs_bmap },
1885 	{ &vop_cachedlookup_desc,	(vop_t *) msdosfs_lookup },
1886 	{ &vop_close_desc,		(vop_t *) msdosfs_close },
1887 	{ &vop_create_desc,		(vop_t *) msdosfs_create },
1888 	{ &vop_fsync_desc,		(vop_t *) msdosfs_fsync },
1889 	{ &vop_getattr_desc,		(vop_t *) msdosfs_getattr },
1890 	{ &vop_inactive_desc,		(vop_t *) msdosfs_inactive },
1891 	{ &vop_link_desc,		(vop_t *) msdosfs_link },
1892 	{ &vop_lookup_desc,		(vop_t *) vfs_cache_lookup },
1893 	{ &vop_mkdir_desc,		(vop_t *) msdosfs_mkdir },
1894 	{ &vop_mknod_desc,		(vop_t *) msdosfs_mknod },
1895 	{ &vop_pathconf_desc,		(vop_t *) msdosfs_pathconf },
1896 	{ &vop_print_desc,		(vop_t *) msdosfs_print },
1897 	{ &vop_read_desc,		(vop_t *) msdosfs_read },
1898 	{ &vop_readdir_desc,		(vop_t *) msdosfs_readdir },
1899 	{ &vop_reclaim_desc,		(vop_t *) msdosfs_reclaim },
1900 	{ &vop_remove_desc,		(vop_t *) msdosfs_remove },
1901 	{ &vop_rename_desc,		(vop_t *) msdosfs_rename },
1902 	{ &vop_rmdir_desc,		(vop_t *) msdosfs_rmdir },
1903 	{ &vop_setattr_desc,		(vop_t *) msdosfs_setattr },
1904 	{ &vop_strategy_desc,		(vop_t *) msdosfs_strategy },
1905 	{ &vop_symlink_desc,		(vop_t *) msdosfs_symlink },
1906 	{ &vop_write_desc,		(vop_t *) msdosfs_write },
1907 	{ NULL, NULL }
1908 };
1909 static struct vnodeopv_desc msdosfs_vnodeop_opv_desc =
1910 	{ &msdosfs_vnodeop_p, msdosfs_vnodeop_entries };
1911 
1912 VNODEOP_SET(msdosfs_vnodeop_opv_desc);
1913