msdosfs_vfsops.c revision 118047
1/* $FreeBSD: head/sys/fs/msdosfs/msdosfs_vfsops.c 118047 2003-07-26 07:32:23Z phk $ */
2/*	$NetBSD: msdosfs_vfsops.c,v 1.51 1997/11/17 15:36:58 ws 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/conf.h>
54#include <sys/namei.h>
55#include <sys/proc.h>
56#include <sys/kernel.h>
57#include <sys/vnode.h>
58#include <sys/mount.h>
59#include <sys/bio.h>
60#include <sys/buf.h>
61#include <sys/fcntl.h>
62#include <sys/malloc.h>
63#include <sys/stat.h> 				/* defines ALLPERMS */
64#include <sys/mutex.h>
65
66#include <fs/msdosfs/bpb.h>
67#include <fs/msdosfs/bootsect.h>
68#include <fs/msdosfs/direntry.h>
69#include <fs/msdosfs/denode.h>
70#include <fs/msdosfs/msdosfsmount.h>
71#include <fs/msdosfs/fat.h>
72
73#define MSDOSFS_DFLTBSIZE       4096
74
75#if 1 /*def PC98*/
76/*
77 * XXX - The boot signature formatted by NEC PC-98 DOS looks like a
78 *       garbage or a random value :-{
79 *       If you want to use that broken-signatured media, define the
80 *       following symbol even though PC/AT.
81 *       (ex. mount PC-98 DOS formatted FD on PC/AT)
82 */
83#define	MSDOSFS_NOCHECKSIG
84#endif
85
86MALLOC_DEFINE(M_MSDOSFSMNT, "MSDOSFS mount", "MSDOSFS mount structure");
87static MALLOC_DEFINE(M_MSDOSFSFAT, "MSDOSFS FAT", "MSDOSFS file allocation table");
88
89static int	update_mp(struct mount *mp, struct msdosfs_args *argp);
90static int	mountmsdosfs(struct vnode *devvp, struct mount *mp,
91		    struct thread *td, struct msdosfs_args *argp);
92static vfs_fhtovp_t	msdosfs_fhtovp;
93static vfs_mount_t	msdosfs_mount;
94static vfs_root_t	msdosfs_root;
95static vfs_statfs_t	msdosfs_statfs;
96static vfs_sync_t	msdosfs_sync;
97static vfs_unmount_t	msdosfs_unmount;
98static vfs_vptofh_t	msdosfs_vptofh;
99
100static int
101update_mp(mp, argp)
102	struct mount *mp;
103	struct msdosfs_args *argp;
104{
105	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
106	int error;
107
108	pmp->pm_gid = argp->gid;
109	pmp->pm_uid = argp->uid;
110	pmp->pm_mask = argp->mask & ALLPERMS;
111	pmp->pm_flags |= argp->flags & MSDOSFSMNT_MNTOPT;
112	if (pmp->pm_flags & MSDOSFSMNT_U2WTABLE) {
113		bcopy(argp->u2w, pmp->pm_u2w, sizeof(pmp->pm_u2w));
114		bcopy(argp->d2u, pmp->pm_d2u, sizeof(pmp->pm_d2u));
115		bcopy(argp->u2d, pmp->pm_u2d, sizeof(pmp->pm_u2d));
116	}
117	if (pmp->pm_flags & MSDOSFSMNT_ULTABLE) {
118		bcopy(argp->ul, pmp->pm_ul, sizeof(pmp->pm_ul));
119		bcopy(argp->lu, pmp->pm_lu, sizeof(pmp->pm_lu));
120	}
121
122	if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
123		pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
124	else if (!(pmp->pm_flags &
125	    (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
126		struct vnode *rootvp;
127
128		/*
129		 * Try to divine whether to support Win'95 long filenames
130		 */
131		if (FAT32(pmp))
132			pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
133		else {
134			if ((error = msdosfs_root(mp, &rootvp)) != 0)
135				return error;
136			pmp->pm_flags |= findwin95(VTODE(rootvp))
137				? MSDOSFSMNT_LONGNAME
138					: MSDOSFSMNT_SHORTNAME;
139			vput(rootvp);
140		}
141	}
142	return 0;
143}
144
145/*
146 * mp - path - addr in user space of mount point (ie /usr or whatever)
147 * data - addr in user space of mount params including the name of the block
148 * special file to treat as a filesystem.
149 */
150static int
151msdosfs_mount(mp, path, data, ndp, td)
152	struct mount *mp;
153	char *path;
154	caddr_t data;
155	struct nameidata *ndp;
156	struct thread *td;
157{
158	struct vnode *devvp;	  /* vnode for blk device to mount */
159	struct msdosfs_args args; /* will hold data from mount request */
160	/* msdosfs specific mount control block */
161	struct msdosfsmount *pmp = NULL;
162	size_t size;
163	int error, flags;
164	mode_t accessmode;
165
166	error = copyin(data, (caddr_t)&args, sizeof(struct msdosfs_args));
167	if (error)
168		return (error);
169	if (args.magic != MSDOSFS_ARGSMAGIC)
170		args.flags = 0;
171	/*
172	 * If updating, check whether changing from read-only to
173	 * read/write; if there is no device name, that's all we do.
174	 */
175	if (mp->mnt_flag & MNT_UPDATE) {
176		pmp = VFSTOMSDOSFS(mp);
177		error = 0;
178		if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && (mp->mnt_flag & MNT_RDONLY)) {
179			flags = WRITECLOSE;
180			if (mp->mnt_flag & MNT_FORCE)
181				flags |= FORCECLOSE;
182			error = vflush(mp, 0, flags);
183		}
184		if (!error && (mp->mnt_flag & MNT_RELOAD))
185			/* not yet implemented */
186			error = EOPNOTSUPP;
187		if (error)
188			return (error);
189		if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
190			/*
191			 * If upgrade to read-write by non-root, then verify
192			 * that user has necessary permissions on the device.
193			 */
194			if (suser(td)) {
195				devvp = pmp->pm_devvp;
196				vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
197				error = VOP_ACCESS(devvp, VREAD | VWRITE,
198						   td->td_ucred, td);
199				if (error) {
200					VOP_UNLOCK(devvp, 0, td);
201					return (error);
202				}
203				VOP_UNLOCK(devvp, 0, td);
204			}
205			pmp->pm_flags &= ~MSDOSFSMNT_RONLY;
206		}
207		if (args.fspec == 0) {
208#ifdef	__notyet__	/* doesn't work correctly with current mountd	XXX */
209			if (args.flags & MSDOSFSMNT_MNTOPT) {
210				pmp->pm_flags &= ~MSDOSFSMNT_MNTOPT;
211				pmp->pm_flags |= args.flags & MSDOSFSMNT_MNTOPT;
212				if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
213					pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
214			}
215#endif
216			/*
217			 * Process export requests.
218			 */
219			return (vfs_export(mp, &args.export));
220		}
221	}
222	/*
223	 * Not an update, or updating the name: look up the name
224	 * and verify that it refers to a sensible block device.
225	 */
226	NDINIT(ndp, LOOKUP, FOLLOW, UIO_USERSPACE, args.fspec, td);
227	error = namei(ndp);
228	if (error)
229		return (error);
230	devvp = ndp->ni_vp;
231	NDFREE(ndp, NDF_ONLY_PNBUF);
232
233	if (!vn_isdisk(devvp, &error)) {
234		vrele(devvp);
235		return (error);
236	}
237	/*
238	 * If mount by non-root, then verify that user has necessary
239	 * permissions on the device.
240	 */
241	if (suser(td)) {
242		accessmode = VREAD;
243		if ((mp->mnt_flag & MNT_RDONLY) == 0)
244			accessmode |= VWRITE;
245		vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
246		error = VOP_ACCESS(devvp, accessmode, td->td_ucred, td);
247		if (error) {
248			vput(devvp);
249			return (error);
250		}
251		VOP_UNLOCK(devvp, 0, td);
252	}
253	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
254		error = mountmsdosfs(devvp, mp, td, &args);
255#ifdef MSDOSFS_DEBUG		/* only needed for the printf below */
256		pmp = VFSTOMSDOSFS(mp);
257#endif
258	} else {
259		if (devvp != pmp->pm_devvp)
260			error = EINVAL;	/* XXX needs translation */
261		else
262			vrele(devvp);
263	}
264	if (error) {
265		vrele(devvp);
266		return (error);
267	}
268
269	error = update_mp(mp, &args);
270	if (error) {
271		msdosfs_unmount(mp, MNT_FORCE, td);
272		return error;
273	}
274	(void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
275	    &size);
276	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
277	(void) msdosfs_statfs(mp, &mp->mnt_stat, td);
278#ifdef MSDOSFS_DEBUG
279	printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap);
280#endif
281	return (0);
282}
283
284static int
285mountmsdosfs(devvp, mp, td, argp)
286	struct vnode *devvp;
287	struct mount *mp;
288	struct thread *td;
289	struct msdosfs_args *argp;
290{
291	struct msdosfsmount *pmp;
292	struct buf *bp;
293	dev_t dev = devvp->v_rdev;
294	union bootsector *bsp;
295	struct byte_bpb33 *b33;
296	struct byte_bpb50 *b50;
297	struct byte_bpb710 *b710;
298	u_int8_t SecPerClust;
299	u_long clusters;
300	int	ronly, error;
301
302	/*
303	 * Disallow multiple mounts of the same device.
304	 * Disallow mounting of a device that is currently in use
305	 * (except for root, which might share swap device for miniroot).
306	 * Flush out any old buffers remaining from a previous use.
307	 */
308	error = vfs_mountedon(devvp);
309	if (error)
310		return (error);
311	if (vcount(devvp) > 1 && devvp != rootvp)
312		return (EBUSY);
313	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
314	error = vinvalbuf(devvp, V_SAVE, td->td_ucred, td, 0, 0);
315	VOP_UNLOCK(devvp, 0, td);
316	if (error)
317		return (error);
318
319	ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
320	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
321	/*
322	 * XXX Open the device with write access even if the filesystem
323	 * is read-only: someone may remount it read-write later, and
324	 * we don't VOP_OPEN the device again in that case.
325	 */
326#ifdef notyet
327	error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, FSCRED, td, -1);
328#else
329	error = VOP_OPEN(devvp, FREAD|FWRITE, FSCRED, td, -1);
330#endif
331	VOP_UNLOCK(devvp, 0, td);
332	if (error)
333		return (error);
334
335	bp  = NULL; /* both used in error_exit */
336	pmp = NULL;
337
338	/*
339	 * Read the boot sector of the filesystem, and then check the
340	 * boot signature.  If not a dos boot sector then error out.
341	 *
342	 * NOTE: 2048 is a maximum sector size in current...
343	 */
344	error = bread(devvp, 0, 2048, NOCRED, &bp);
345	if (error)
346		goto error_exit;
347	bp->b_flags |= B_AGE;
348	bsp = (union bootsector *)bp->b_data;
349	b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
350	b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
351	b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB;
352
353#ifndef MSDOSFS_NOCHECKSIG
354	if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
355	    || bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
356		error = EINVAL;
357		goto error_exit;
358	}
359#endif
360
361	pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO);
362	pmp->pm_mountp = mp;
363
364	/*
365	 * Compute several useful quantities from the bpb in the
366	 * bootsector.  Copy in the dos 5 variant of the bpb then fix up
367	 * the fields that are different between dos 5 and dos 3.3.
368	 */
369	SecPerClust = b50->bpbSecPerClust;
370	pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
371	if (pmp->pm_BytesPerSec < DEV_BSIZE) {
372		error = EINVAL;
373		goto error_exit;
374	}
375	pmp->pm_ResSectors = getushort(b50->bpbResSectors);
376	pmp->pm_FATs = b50->bpbFATs;
377	pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
378	pmp->pm_Sectors = getushort(b50->bpbSectors);
379	pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
380	pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
381	pmp->pm_Heads = getushort(b50->bpbHeads);
382	pmp->pm_Media = b50->bpbMedia;
383
384	/* calculate the ratio of sector size to DEV_BSIZE */
385	pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE;
386
387	/* XXX - We should probably check more values here */
388	if (!pmp->pm_BytesPerSec || !SecPerClust
389		|| !pmp->pm_Heads || pmp->pm_Heads > 255
390#ifdef PC98
391    		|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 255) {
392#else
393		|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) {
394#endif
395		error = EINVAL;
396		goto error_exit;
397	}
398
399	if (pmp->pm_Sectors == 0) {
400		pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
401		pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
402	} else {
403		pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
404		pmp->pm_HugeSectors = pmp->pm_Sectors;
405	}
406	if (pmp->pm_HugeSectors > 0xffffffff /
407	    (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) {
408		/*
409		 * We cannot deal currently with this size of disk
410		 * due to fileid limitations (see msdosfs_getattr and
411		 * msdosfs_readdir)
412		 */
413		error = EINVAL;
414		printf("mountmsdosfs(): disk too big, sorry\n");
415		goto error_exit;
416	}
417
418	if (pmp->pm_RootDirEnts == 0) {
419		if (bsp->bs710.bsBootSectSig2 != BOOTSIG2
420		    || bsp->bs710.bsBootSectSig3 != BOOTSIG3
421		    || pmp->pm_Sectors
422		    || pmp->pm_FATsecs
423		    || getushort(b710->bpbFSVers)) {
424			error = EINVAL;
425			printf("mountmsdosfs(): bad FAT32 filesystem\n");
426			goto error_exit;
427		}
428		pmp->pm_fatmask = FAT32_MASK;
429		pmp->pm_fatmult = 4;
430		pmp->pm_fatdiv = 1;
431		pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
432		if (getushort(b710->bpbExtFlags) & FATMIRROR)
433			pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
434		else
435			pmp->pm_flags |= MSDOSFS_FATMIRROR;
436	} else
437		pmp->pm_flags |= MSDOSFS_FATMIRROR;
438
439	/*
440	 * Check a few values (could do some more):
441	 * - logical sector size: power of 2, >= block size
442	 * - sectors per cluster: power of 2, >= 1
443	 * - number of sectors:   >= 1, <= size of partition
444	 * - number of FAT sectors: >= 1
445	 */
446	if ( (SecPerClust == 0)
447	  || (SecPerClust & (SecPerClust - 1))
448	  || (pmp->pm_BytesPerSec < DEV_BSIZE)
449	  || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
450	  || (pmp->pm_HugeSectors == 0)
451	  || (pmp->pm_FATsecs == 0)
452	) {
453		error = EINVAL;
454		goto error_exit;
455	}
456
457	pmp->pm_HugeSectors *= pmp->pm_BlkPerSec;
458	pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */
459	pmp->pm_FATsecs     *= pmp->pm_BlkPerSec;
460	SecPerClust         *= pmp->pm_BlkPerSec;
461
462	pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec;
463
464	if (FAT32(pmp)) {
465		pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
466		pmp->pm_firstcluster = pmp->pm_fatblk
467			+ (pmp->pm_FATs * pmp->pm_FATsecs);
468		pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec;
469	} else {
470		pmp->pm_rootdirblk = pmp->pm_fatblk +
471			(pmp->pm_FATs * pmp->pm_FATsecs);
472		pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry)
473				       + DEV_BSIZE - 1)
474			/ DEV_BSIZE; /* in blocks */
475		pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
476	}
477
478	pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
479	    SecPerClust + 1;
480	pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */
481
482	if (pmp->pm_fatmask == 0) {
483		if (pmp->pm_maxcluster
484		    <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
485			/*
486			 * This will usually be a floppy disk. This size makes
487			 * sure that one fat entry will not be split across
488			 * multiple blocks.
489			 */
490			pmp->pm_fatmask = FAT12_MASK;
491			pmp->pm_fatmult = 3;
492			pmp->pm_fatdiv = 2;
493		} else {
494			pmp->pm_fatmask = FAT16_MASK;
495			pmp->pm_fatmult = 2;
496			pmp->pm_fatdiv = 1;
497		}
498	}
499
500	clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv;
501	if (pmp->pm_maxcluster >= clusters) {
502		printf("Warning: number of clusters (%ld) exceeds FAT "
503		    "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters);
504		pmp->pm_maxcluster = clusters - 1;
505	}
506
507
508	if (FAT12(pmp))
509		pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec;
510	else
511		pmp->pm_fatblocksize = MSDOSFS_DFLTBSIZE;
512
513	pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE;
514	pmp->pm_bnshift = ffs(DEV_BSIZE) - 1;
515
516	/*
517	 * Compute mask and shift value for isolating cluster relative byte
518	 * offsets and cluster numbers from a file offset.
519	 */
520	pmp->pm_bpcluster = SecPerClust * DEV_BSIZE;
521	pmp->pm_crbomask = pmp->pm_bpcluster - 1;
522	pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
523
524	/*
525	 * Check for valid cluster size
526	 * must be a power of 2
527	 */
528	if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
529		error = EINVAL;
530		goto error_exit;
531	}
532
533	/*
534	 * Release the bootsector buffer.
535	 */
536	brelse(bp);
537	bp = NULL;
538
539	/*
540	 * Check FSInfo.
541	 */
542	if (pmp->pm_fsinfo) {
543		struct fsinfo *fp;
544
545		if ((error = bread(devvp, pmp->pm_fsinfo, fsi_size(pmp),
546		    NOCRED, &bp)) != 0)
547			goto error_exit;
548		fp = (struct fsinfo *)bp->b_data;
549		if (!bcmp(fp->fsisig1, "RRaA", 4)
550		    && !bcmp(fp->fsisig2, "rrAa", 4)
551		    && !bcmp(fp->fsisig3, "\0\0\125\252", 4)
552		    && !bcmp(fp->fsisig4, "\0\0\125\252", 4))
553			pmp->pm_nxtfree = getulong(fp->fsinxtfree);
554		else
555			pmp->pm_fsinfo = 0;
556		brelse(bp);
557		bp = NULL;
558	}
559
560	/*
561	 * Check and validate (or perhaps invalidate?) the fsinfo structure?
562	 */
563	if (pmp->pm_fsinfo && pmp->pm_nxtfree > pmp->pm_maxcluster) {
564		printf(
565		"Next free cluster in FSInfo (%lu) exceeds maxcluster (%lu)\n",
566		    pmp->pm_nxtfree, pmp->pm_maxcluster);
567		error = EINVAL;
568		goto error_exit;
569	}
570
571	/*
572	 * Allocate memory for the bitmap of allocated clusters, and then
573	 * fill it in.
574	 */
575	pmp->pm_inusemap = malloc(((pmp->pm_maxcluster + N_INUSEBITS - 1)
576				   / N_INUSEBITS)
577				  * sizeof(*pmp->pm_inusemap),
578				  M_MSDOSFSFAT, M_WAITOK);
579
580	/*
581	 * fillinusemap() needs pm_devvp.
582	 */
583	pmp->pm_dev = dev;
584	pmp->pm_devvp = devvp;
585
586	/*
587	 * Have the inuse map filled in.
588	 */
589	if ((error = fillinusemap(pmp)) != 0)
590		goto error_exit;
591
592	/*
593	 * If they want fat updates to be synchronous then let them suffer
594	 * the performance degradation in exchange for the on disk copy of
595	 * the fat being correct just about all the time.  I suppose this
596	 * would be a good thing to turn on if the kernel is still flakey.
597	 */
598	if (mp->mnt_flag & MNT_SYNCHRONOUS)
599		pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
600
601	/*
602	 * Finish up.
603	 */
604	if (ronly)
605		pmp->pm_flags |= MSDOSFSMNT_RONLY;
606	else
607		pmp->pm_fmod = 1;
608	mp->mnt_data = (qaddr_t) pmp;
609	mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
610	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
611	mp->mnt_flag |= MNT_LOCAL;
612	devvp->v_rdev->si_mountpoint = mp;
613
614	return 0;
615
616error_exit:
617	if (bp)
618		brelse(bp);
619	/* XXX See comment at VOP_OPEN call */
620#ifdef notyet
621	(void) VOP_CLOSE(devvp, ronly ? FREAD : FREAD | FWRITE, NOCRED, td);
622#else
623	(void) VOP_CLOSE(devvp, FREAD | FWRITE, NOCRED, td);
624#endif
625	if (pmp) {
626		if (pmp->pm_inusemap)
627			free(pmp->pm_inusemap, M_MSDOSFSFAT);
628		free(pmp, M_MSDOSFSMNT);
629		mp->mnt_data = (qaddr_t)0;
630	}
631	return (error);
632}
633
634/*
635 * Unmount the filesystem described by mp.
636 */
637static int
638msdosfs_unmount(mp, mntflags, td)
639	struct mount *mp;
640	int mntflags;
641	struct thread *td;
642{
643	struct msdosfsmount *pmp;
644	int error, flags;
645
646	flags = 0;
647	if (mntflags & MNT_FORCE)
648		flags |= FORCECLOSE;
649	error = vflush(mp, 0, flags);
650	if (error)
651		return error;
652	pmp = VFSTOMSDOSFS(mp);
653	pmp->pm_devvp->v_rdev->si_mountpoint = NULL;
654#ifdef MSDOSFS_DEBUG
655	{
656		struct vnode *vp = pmp->pm_devvp;
657
658		VI_LOCK(vp);
659		printf("msdosfs_umount(): just before calling VOP_CLOSE()\n");
660		printf("iflag %08lx, usecount %d, writecount %d, holdcnt %ld\n",
661		    vp->vi_flag, vp->v_usecount, vp->v_writecount,
662		    vp->v_holdcnt);
663		printf("id %lu, mount %p, op %p\n",
664		    vp->v_id, vp->v_mount, vp->v_op);
665		printf("freef %p, freeb %p, mount %p\n",
666		    TAILQ_NEXT(vp, v_freelist), vp->v_freelist.tqe_prev,
667		    vp->v_mount);
668		printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n",
669		    TAILQ_FIRST(&vp->v_cleanblkhd),
670		    TAILQ_FIRST(&vp->v_dirtyblkhd),
671		    vp->v_numoutput, vp->v_type);
672		printf("union %p, tag %s, data[0] %08x, data[1] %08x\n",
673		    vp->v_socket, vp->v_tag,
674		    ((u_int *)vp->v_data)[0],
675		    ((u_int *)vp->v_data)[1]);
676		VI_UNLOCK(vp);
677	}
678#endif
679	/* XXX See comment at VOP_OPEN call */
680#ifdef notyet
681	error = VOP_CLOSE(pmp->pm_devvp,
682		    (pmp->pm_flags&MSDOSFSMNT_RONLY) ? FREAD : FREAD | FWRITE,
683		    NOCRED, td);
684#else
685	error = VOP_CLOSE(pmp->pm_devvp, FREAD | FWRITE, NOCRED, td);
686#endif
687	vrele(pmp->pm_devvp);
688	free(pmp->pm_inusemap, M_MSDOSFSFAT);
689	free(pmp, M_MSDOSFSMNT);
690	mp->mnt_data = (qaddr_t)0;
691	mp->mnt_flag &= ~MNT_LOCAL;
692	return (error);
693}
694
695static int
696msdosfs_root(mp, vpp)
697	struct mount *mp;
698	struct vnode **vpp;
699{
700	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
701	struct denode *ndep;
702	int error;
703
704#ifdef MSDOSFS_DEBUG
705	printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp);
706#endif
707	error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep);
708	if (error)
709		return (error);
710	*vpp = DETOV(ndep);
711	return (0);
712}
713
714static int
715msdosfs_statfs(mp, sbp, td)
716	struct mount *mp;
717	struct statfs *sbp;
718	struct thread *td;
719{
720	struct msdosfsmount *pmp;
721
722	pmp = VFSTOMSDOSFS(mp);
723	sbp->f_bsize = pmp->pm_bpcluster;
724	sbp->f_iosize = pmp->pm_bpcluster;
725	sbp->f_blocks = pmp->pm_maxcluster + 1;
726	sbp->f_bfree = pmp->pm_freeclustercount;
727	sbp->f_bavail = pmp->pm_freeclustercount;
728	sbp->f_files = pmp->pm_RootDirEnts;			/* XXX */
729	sbp->f_ffree = 0;	/* what to put in here? */
730	if (sbp != &mp->mnt_stat) {
731		sbp->f_type = mp->mnt_vfc->vfc_typenum;
732		bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
733		bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
734	}
735	strncpy(sbp->f_fstypename, mp->mnt_vfc->vfc_name, MFSNAMELEN);
736	return (0);
737}
738
739static int
740msdosfs_sync(mp, waitfor, cred, td)
741	struct mount *mp;
742	int waitfor;
743	struct ucred *cred;
744	struct thread *td;
745{
746	struct vnode *vp, *nvp;
747	struct denode *dep;
748	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
749	int error, allerror = 0;
750
751	/*
752	 * If we ever switch to not updating all of the fats all the time,
753	 * this would be the place to update them from the first one.
754	 */
755	if (pmp->pm_fmod != 0) {
756		if (pmp->pm_flags & MSDOSFSMNT_RONLY)
757			panic("msdosfs_sync: rofs mod");
758		else {
759			/* update fats here */
760		}
761	}
762	/*
763	 * Write back each (modified) denode.
764	 */
765	mtx_lock(&mntvnode_mtx);
766loop:
767	for (vp = TAILQ_FIRST(&mp->mnt_nvnodelist); vp != NULL; vp = nvp) {
768		/*
769		 * If the vnode that we are about to sync is no longer
770		 * associated with this mount point, start over.
771		 */
772		if (vp->v_mount != mp)
773			goto loop;
774		nvp = TAILQ_NEXT(vp, v_nmntvnodes);
775
776		mtx_unlock(&mntvnode_mtx);
777		VI_LOCK(vp);
778		dep = VTODE(vp);
779		if (vp->v_type == VNON ||
780		    ((dep->de_flag &
781		    (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 &&
782		    (TAILQ_EMPTY(&vp->v_dirtyblkhd) || waitfor == MNT_LAZY))) {
783			VI_UNLOCK(vp);
784			mtx_lock(&mntvnode_mtx);
785			continue;
786		}
787		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
788		if (error) {
789			mtx_lock(&mntvnode_mtx);
790			if (error == ENOENT)
791				goto loop;
792			continue;
793		}
794		error = VOP_FSYNC(vp, cred, waitfor, td);
795		if (error)
796			allerror = error;
797		VOP_UNLOCK(vp, 0, td);
798		vrele(vp);
799		mtx_lock(&mntvnode_mtx);
800	}
801	mtx_unlock(&mntvnode_mtx);
802
803	/*
804	 * Flush filesystem control info.
805	 */
806	if (waitfor != MNT_LAZY) {
807		vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY, td);
808		error = VOP_FSYNC(pmp->pm_devvp, cred, waitfor, td);
809		if (error)
810			allerror = error;
811		VOP_UNLOCK(pmp->pm_devvp, 0, td);
812	}
813	return (allerror);
814}
815
816static int
817msdosfs_fhtovp(mp, fhp, vpp)
818	struct mount *mp;
819	struct fid *fhp;
820	struct vnode **vpp;
821{
822	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
823	struct defid *defhp = (struct defid *) fhp;
824	struct denode *dep;
825	int error;
826
827	error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep);
828	if (error) {
829		*vpp = NULLVP;
830		return (error);
831	}
832	*vpp = DETOV(dep);
833	return (0);
834}
835
836static int
837msdosfs_vptofh(vp, fhp)
838	struct vnode *vp;
839	struct fid *fhp;
840{
841	struct denode *dep;
842	struct defid *defhp;
843
844	dep = VTODE(vp);
845	defhp = (struct defid *)fhp;
846	defhp->defid_len = sizeof(struct defid);
847	defhp->defid_dirclust = dep->de_dirclust;
848	defhp->defid_dirofs = dep->de_diroffset;
849	/* defhp->defid_gen = dep->de_gen; */
850	return (0);
851}
852
853static struct vfsops msdosfs_vfsops = {
854	.vfs_fhtovp =		msdosfs_fhtovp,
855	.vfs_init =		msdosfs_init,
856	.vfs_mount =		msdosfs_mount,
857	.vfs_root =		msdosfs_root,
858	.vfs_statfs =		msdosfs_statfs,
859	.vfs_sync =		msdosfs_sync,
860	.vfs_uninit =		msdosfs_uninit,
861	.vfs_unmount =		msdosfs_unmount,
862	.vfs_vptofh =		msdosfs_vptofh,
863};
864
865VFS_SET(msdosfs_vfsops, msdosfs, 0);
866