msdosfs_vfsops.c revision 151897
1/* $FreeBSD: head/sys/fs/msdosfs/msdosfs_vfsops.c 151897 2005-10-31 15:41:29Z rwatson $ */
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/iconv.h>
65#include <sys/mutex.h>
66
67#include <fs/msdosfs/bpb.h>
68#include <fs/msdosfs/bootsect.h>
69#include <fs/msdosfs/msdosfsmount.h>
70#include <fs/msdosfs/direntry.h>
71#include <fs/msdosfs/denode.h>
72#include <fs/msdosfs/fat.h>
73
74#include <geom/geom.h>
75#include <geom/geom_vfs.h>
76
77#include "opt_msdosfs.h"
78
79/* List of mount options we support */
80static const char *msdosfs_opts[] = {
81	"from",
82	"export",
83	"uid", "gid", "mask", "dirmask",
84	"shortname", "longname", "win95",
85	"kiconv", "cs_win", "cs_dos", "cs_local",
86	NULL
87};
88
89#define MSDOSFS_DFLTBSIZE       4096
90
91#if 1 /*def PC98*/
92/*
93 * XXX - The boot signature formatted by NEC PC-98 DOS looks like a
94 *       garbage or a random value :-{
95 *       If you want to use that broken-signatured media, define the
96 *       following symbol even though PC/AT.
97 *       (ex. mount PC-98 DOS formatted FD on PC/AT)
98 */
99#define	MSDOSFS_NOCHECKSIG
100#endif
101
102MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure");
103static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table");
104
105struct iconv_functions *msdosfs_iconv = NULL;
106
107static int	update_mp(struct mount *mp, struct thread *td);
108static int	mountmsdosfs(struct vnode *devvp, struct mount *mp,
109		    struct thread *td);
110static vfs_fhtovp_t	msdosfs_fhtovp;
111static vfs_mount_t	msdosfs_mount;
112static vfs_root_t	msdosfs_root;
113static vfs_statfs_t	msdosfs_statfs;
114static vfs_sync_t	msdosfs_sync;
115static vfs_unmount_t	msdosfs_unmount;
116static vfs_vptofh_t	msdosfs_vptofh;
117
118/* Maximum length of a character set name (arbitrary). */
119#define	MAXCSLEN	64
120
121static int
122update_mp(mp, td)
123	struct mount *mp;
124	struct thread *td;
125{
126	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
127	void *dos, *win, *local;
128	int error, v;
129
130	if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) {
131		if (msdosfs_iconv != NULL) {
132			error = vfs_getopt(mp->mnt_optnew,
133			    "cs_win", &win, NULL);
134			if (!error)
135				error = vfs_getopt(mp->mnt_optnew,
136				    "cs_local", &local, NULL);
137			if (!error)
138				error = vfs_getopt(mp->mnt_optnew,
139				    "cs_dos", &dos, NULL);
140			if (!error) {
141				msdosfs_iconv->open(win, local, &pmp->pm_u2w);
142				msdosfs_iconv->open(local, win, &pmp->pm_w2u);
143				msdosfs_iconv->open(dos, local, &pmp->pm_u2d);
144				msdosfs_iconv->open(local, dos, &pmp->pm_d2u);
145			}
146			if (error != 0)
147				return (error);
148		} else {
149			pmp->pm_w2u = NULL;
150			pmp->pm_u2w = NULL;
151			pmp->pm_d2u = NULL;
152			pmp->pm_u2d = NULL;
153		}
154	}
155
156	if (1 == vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v))
157		pmp->pm_gid = v;
158	if (1 == vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v))
159		pmp->pm_uid = v;
160	if (1 == vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v))
161		pmp->pm_mask = v & ALLPERMS;
162	if (1 == vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v))
163		pmp->pm_dirmask = v & ALLPERMS;
164	vfs_flagopt(mp->mnt_optnew, "shortname",
165	    &pmp->pm_flags, MSDOSFSMNT_SHORTNAME);
166	vfs_flagopt(mp->mnt_optnew, "longname",
167	    &pmp->pm_flags, MSDOSFSMNT_LONGNAME);
168	vfs_flagopt(mp->mnt_optnew, "kiconv",
169	    &pmp->pm_flags, MSDOSFSMNT_KICONV);
170
171	/* XXX: Can't use flagopt due to negative option */
172	if (!vfs_getopt(mp->mnt_optnew, "win95", NULL, NULL))
173		pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95;
174	else
175		pmp->pm_flags |= MSDOSFSMNT_NOWIN95;
176
177	if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
178		pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
179	else if (!(pmp->pm_flags &
180	    (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
181		struct vnode *rootvp;
182
183		/*
184		 * Try to divine whether to support Win'95 long filenames
185		 */
186		if (FAT32(pmp))
187			pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
188		else {
189			if ((error =
190			    msdosfs_root(mp, LK_EXCLUSIVE, &rootvp, td)) != 0)
191				return error;
192			pmp->pm_flags |= findwin95(VTODE(rootvp))
193				? MSDOSFSMNT_LONGNAME
194					: MSDOSFSMNT_SHORTNAME;
195			vput(rootvp);
196		}
197	}
198	return 0;
199}
200
201static int
202msdosfs_cmount(struct mntarg *ma, void *data, int flags, struct thread *td)
203{
204	struct msdosfs_args args;
205	int error;
206
207	if (data == NULL)
208		return (EINVAL);
209	error = copyin(data, &args, sizeof args);
210	if (error)
211		return (error);
212
213	ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN);
214	ma = mount_arg(ma, "export", &args.export, sizeof args.export);
215	ma = mount_argf(ma, "uid", "%d", args.uid);
216	ma = mount_argf(ma, "gid", "%d", args.gid);
217	ma = mount_argf(ma, "mask", "%d", args.mask);
218	ma = mount_argf(ma, "dirmask", "%d", args.dirmask);
219
220        ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname");
221        ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname");
222        ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95");
223        ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv");
224
225        ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN);
226        ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN);
227        ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN);
228
229	error = kernel_mount(ma, flags);
230
231	return (error);
232}
233
234/*
235 * mp - path - addr in user space of mount point (ie /usr or whatever)
236 * data - addr in user space of mount params including the name of the block
237 * special file to treat as a filesystem.
238 */
239static int
240msdosfs_mount(struct mount *mp, struct thread *td)
241{
242	struct vnode *devvp;	  /* vnode for blk device to mount */
243	struct export_args export;
244	/* msdosfs specific mount control block */
245	struct msdosfsmount *pmp = NULL;
246	struct nameidata ndp;
247	int error, flags;
248	mode_t accessmode;
249	char *from;
250
251	if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts))
252		return (EINVAL);
253
254	/*
255	 * If updating, check whether changing from read-only to
256	 * read/write; if there is no device name, that's all we do.
257	 */
258	if (mp->mnt_flag & MNT_UPDATE) {
259		pmp = VFSTOMSDOSFS(mp);
260
261		error = vfs_copyopt(mp->mnt_optnew, "export",
262		    &export, sizeof export);
263		if (error == 0 && export.ex_flags != 0) {
264			/*
265			 * Process export requests.
266			 */
267			if ((export.ex_flags & MNT_EXPORTED) != 0 &&
268			    (pmp->pm_flags & MSDOSFS_LARGEFS) != 0)
269				return (EOPNOTSUPP);
270			return (vfs_export(mp, &export));
271		}
272		if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) &&
273		    vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
274			error = VFS_SYNC(mp, MNT_WAIT, td);
275			if (error)
276				return (error);
277			flags = WRITECLOSE;
278			if (mp->mnt_flag & MNT_FORCE)
279				flags |= FORCECLOSE;
280			error = vflush(mp, 0, flags, td);
281			if (error)
282				return (error);
283			DROP_GIANT();
284			g_topology_lock();
285			g_access(pmp->pm_cp, 0, -1, 0);
286			g_topology_unlock();
287			PICKUP_GIANT();
288		} else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) &&
289		    !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
290			/*
291			 * If upgrade to read-write by non-root, then verify
292			 * that user has necessary permissions on the device.
293			 */
294			if (suser(td)) {
295				devvp = pmp->pm_devvp;
296				vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td);
297				error = VOP_ACCESS(devvp, VREAD | VWRITE,
298						   td->td_ucred, td);
299				if (error) {
300					VOP_UNLOCK(devvp, 0, td);
301					return (error);
302				}
303				VOP_UNLOCK(devvp, 0, td);
304			}
305			DROP_GIANT();
306			g_topology_lock();
307			error = g_access(pmp->pm_cp, 0, 1, 0);
308			g_topology_unlock();
309			PICKUP_GIANT();
310			if (error)
311				return (error);
312
313			/* Now that the volume is modifiable, mark it dirty. */
314			error = markvoldirty(pmp, 1);
315			if (error)
316				return (error);
317		}
318		vfs_flagopt(mp->mnt_optnew, "ro",
319		    &pmp->pm_flags, MSDOSFSMNT_RONLY);
320		vfs_flagopt(mp->mnt_optnew, "ro",
321		    &mp->mnt_flag, MNT_RDONLY);
322		if (vfs_getopt(mp->mnt_optnew, "from", NULL, NULL)) {
323#ifdef	__notyet__	/* doesn't work correctly with current mountd	XXX */
324			if (args.flags & MSDOSFSMNT_MNTOPT) {
325				pmp->pm_flags &= ~MSDOSFSMNT_MNTOPT;
326				pmp->pm_flags |= args.flags & MSDOSFSMNT_MNTOPT;
327				if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
328					pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
329			}
330#endif
331		}
332	}
333	/*
334	 * Not an update, or updating the name: look up the name
335	 * and verify that it refers to a sensible disk device.
336	 */
337	if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL))
338		return (EINVAL);
339	NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td);
340	error = namei(&ndp);
341	if (error)
342		return (error);
343	devvp = ndp.ni_vp;
344	NDFREE(&ndp, NDF_ONLY_PNBUF);
345
346	if (!vn_isdisk(devvp, &error)) {
347		vput(devvp);
348		return (error);
349	}
350	/*
351	 * If mount by non-root, then verify that user has necessary
352	 * permissions on the device.
353	 */
354	if (suser(td)) {
355		accessmode = VREAD;
356		if ((mp->mnt_flag & MNT_RDONLY) == 0)
357			accessmode |= VWRITE;
358		error = VOP_ACCESS(devvp, accessmode, td->td_ucred, td);
359		if (error) {
360			vput(devvp);
361			return (error);
362		}
363	}
364	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
365		error = mountmsdosfs(devvp, mp, td);
366#ifdef MSDOSFS_DEBUG		/* only needed for the printf below */
367		pmp = VFSTOMSDOSFS(mp);
368#endif
369	} else {
370		if (devvp != pmp->pm_devvp)
371			error = EINVAL;	/* XXX needs translation */
372		else
373			vput(devvp);
374	}
375	if (error) {
376		vrele(devvp);
377		return (error);
378	}
379
380	error = update_mp(mp, td);
381	if (error) {
382		if ((mp->mnt_flag & MNT_UPDATE) == 0)
383			msdosfs_unmount(mp, MNT_FORCE, td);
384		return error;
385	}
386
387	vfs_mountedfrom(mp, from);
388#ifdef MSDOSFS_DEBUG
389	printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap);
390#endif
391	return (0);
392}
393
394static int
395mountmsdosfs(devvp, mp, td)
396	struct vnode *devvp;
397	struct mount *mp;
398	struct thread *td;
399{
400	struct msdosfsmount *pmp;
401	struct buf *bp;
402	struct cdev *dev = devvp->v_rdev;
403	union bootsector *bsp;
404	struct byte_bpb33 *b33;
405	struct byte_bpb50 *b50;
406	struct byte_bpb710 *b710;
407	u_int8_t SecPerClust;
408	u_long clusters;
409	int	ronly, error;
410	struct g_consumer *cp;
411	struct bufobj *bo;
412
413	ronly = !vfs_getopt(mp->mnt_optnew, "ro", NULL, NULL);
414	/* XXX: use VOP_ACCESS to check FS perms */
415	DROP_GIANT();
416	g_topology_lock();
417	error = g_vfs_open(devvp, &cp, "msdos", ronly ? 0 : 1);
418	g_topology_unlock();
419	PICKUP_GIANT();
420	VOP_UNLOCK(devvp, 0, td);
421	if (error)
422		return (error);
423
424	bo = &devvp->v_bufobj;
425	bp  = NULL; /* both used in error_exit */
426	pmp = NULL;
427
428	/*
429	 * Read the boot sector of the filesystem, and then check the
430	 * boot signature.  If not a dos boot sector then error out.
431	 *
432	 * NOTE: 2048 is a maximum sector size in current...
433	 */
434	error = bread(devvp, 0, 2048, NOCRED, &bp);
435	if (error)
436		goto error_exit;
437	bp->b_flags |= B_AGE;
438	bsp = (union bootsector *)bp->b_data;
439	b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
440	b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
441	b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB;
442
443#ifndef MSDOSFS_NOCHECKSIG
444	if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
445	    || bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
446		error = EINVAL;
447		goto error_exit;
448	}
449#endif
450
451	pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO);
452	pmp->pm_mountp = mp;
453	pmp->pm_cp = cp;
454	pmp->pm_bo = bo;
455
456	/*
457	 * Compute several useful quantities from the bpb in the
458	 * bootsector.  Copy in the dos 5 variant of the bpb then fix up
459	 * the fields that are different between dos 5 and dos 3.3.
460	 */
461	SecPerClust = b50->bpbSecPerClust;
462	pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
463	if (pmp->pm_BytesPerSec < DEV_BSIZE) {
464		error = EINVAL;
465		goto error_exit;
466	}
467	pmp->pm_ResSectors = getushort(b50->bpbResSectors);
468	pmp->pm_FATs = b50->bpbFATs;
469	pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
470	pmp->pm_Sectors = getushort(b50->bpbSectors);
471	pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
472	pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
473	pmp->pm_Heads = getushort(b50->bpbHeads);
474	pmp->pm_Media = b50->bpbMedia;
475
476	/* calculate the ratio of sector size to DEV_BSIZE */
477	pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE;
478
479	/* XXX - We should probably check more values here */
480	if (!pmp->pm_BytesPerSec || !SecPerClust
481		|| !pmp->pm_Heads
482#ifdef PC98
483    		|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 255) {
484#else
485		|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) {
486#endif
487		error = EINVAL;
488		goto error_exit;
489	}
490
491	if (pmp->pm_Sectors == 0) {
492		pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
493		pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
494	} else {
495		pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
496		pmp->pm_HugeSectors = pmp->pm_Sectors;
497	}
498#ifndef MSDOSFS_LARGE
499	if (pmp->pm_HugeSectors > 0xffffffff /
500	    (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) {
501		/*
502		 * We cannot deal currently with this size of disk
503		 * due to fileid limitations (see msdosfs_getattr and
504		 * msdosfs_readdir)
505		 */
506		error = EINVAL;
507		printf("mountmsdosfs(): disk too big, sorry\n");
508		goto error_exit;
509	}
510#endif	/* !MSDOSFS_LARGE */
511
512	if (pmp->pm_RootDirEnts == 0) {
513		if (pmp->pm_Sectors
514		    || pmp->pm_FATsecs
515		    || getushort(b710->bpbFSVers)) {
516			error = EINVAL;
517			printf("mountmsdosfs(): bad FAT32 filesystem\n");
518			goto error_exit;
519		}
520		pmp->pm_fatmask = FAT32_MASK;
521		pmp->pm_fatmult = 4;
522		pmp->pm_fatdiv = 1;
523		pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
524		if (getushort(b710->bpbExtFlags) & FATMIRROR)
525			pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
526		else
527			pmp->pm_flags |= MSDOSFS_FATMIRROR;
528	} else
529		pmp->pm_flags |= MSDOSFS_FATMIRROR;
530
531	/*
532	 * Check a few values (could do some more):
533	 * - logical sector size: power of 2, >= block size
534	 * - sectors per cluster: power of 2, >= 1
535	 * - number of sectors:   >= 1, <= size of partition
536	 * - number of FAT sectors: >= 1
537	 */
538	if ( (SecPerClust == 0)
539	  || (SecPerClust & (SecPerClust - 1))
540	  || (pmp->pm_BytesPerSec < DEV_BSIZE)
541	  || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
542	  || (pmp->pm_HugeSectors == 0)
543	  || (pmp->pm_FATsecs == 0)
544	) {
545		error = EINVAL;
546		goto error_exit;
547	}
548
549	pmp->pm_HugeSectors *= pmp->pm_BlkPerSec;
550	pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */
551	pmp->pm_FATsecs     *= pmp->pm_BlkPerSec;
552	SecPerClust         *= pmp->pm_BlkPerSec;
553
554	pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec;
555
556	if (FAT32(pmp)) {
557		pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
558		pmp->pm_firstcluster = pmp->pm_fatblk
559			+ (pmp->pm_FATs * pmp->pm_FATsecs);
560		pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec;
561	} else {
562		pmp->pm_rootdirblk = pmp->pm_fatblk +
563			(pmp->pm_FATs * pmp->pm_FATsecs);
564		pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry)
565				       + DEV_BSIZE - 1)
566			/ DEV_BSIZE; /* in blocks */
567		pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
568	}
569
570	pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
571	    SecPerClust + 1;
572	pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */
573
574	if (pmp->pm_fatmask == 0) {
575		if (pmp->pm_maxcluster
576		    <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
577			/*
578			 * This will usually be a floppy disk. This size makes
579			 * sure that one fat entry will not be split across
580			 * multiple blocks.
581			 */
582			pmp->pm_fatmask = FAT12_MASK;
583			pmp->pm_fatmult = 3;
584			pmp->pm_fatdiv = 2;
585		} else {
586			pmp->pm_fatmask = FAT16_MASK;
587			pmp->pm_fatmult = 2;
588			pmp->pm_fatdiv = 1;
589		}
590	}
591
592	clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv;
593	if (pmp->pm_maxcluster >= clusters) {
594		printf("Warning: number of clusters (%ld) exceeds FAT "
595		    "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters);
596		pmp->pm_maxcluster = clusters - 1;
597	}
598
599
600	if (FAT12(pmp))
601		pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec;
602	else
603		pmp->pm_fatblocksize = MSDOSFS_DFLTBSIZE;
604
605	pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE;
606	pmp->pm_bnshift = ffs(DEV_BSIZE) - 1;
607
608	/*
609	 * Compute mask and shift value for isolating cluster relative byte
610	 * offsets and cluster numbers from a file offset.
611	 */
612	pmp->pm_bpcluster = SecPerClust * DEV_BSIZE;
613	pmp->pm_crbomask = pmp->pm_bpcluster - 1;
614	pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
615
616	/*
617	 * Check for valid cluster size
618	 * must be a power of 2
619	 */
620	if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
621		error = EINVAL;
622		goto error_exit;
623	}
624
625	/*
626	 * Release the bootsector buffer.
627	 */
628	brelse(bp);
629	bp = NULL;
630
631	/*
632	 * Check FSInfo.
633	 */
634	if (pmp->pm_fsinfo) {
635		struct fsinfo *fp;
636
637		if ((error = bread(devvp, pmp->pm_fsinfo, fsi_size(pmp),
638		    NOCRED, &bp)) != 0)
639			goto error_exit;
640		fp = (struct fsinfo *)bp->b_data;
641		if (!bcmp(fp->fsisig1, "RRaA", 4)
642		    && !bcmp(fp->fsisig2, "rrAa", 4)
643		    && !bcmp(fp->fsisig3, "\0\0\125\252", 4)
644		    && !bcmp(fp->fsisig4, "\0\0\125\252", 4)) {
645			pmp->pm_nxtfree = getulong(fp->fsinxtfree);
646			if (pmp->pm_nxtfree == 0xffffffff)
647				pmp->pm_nxtfree = CLUST_FIRST;
648		} else
649			pmp->pm_fsinfo = 0;
650		brelse(bp);
651		bp = NULL;
652	}
653
654	/*
655	 * Check and validate (or perhaps invalidate?) the fsinfo structure?
656	 */
657	if (pmp->pm_fsinfo && pmp->pm_nxtfree > pmp->pm_maxcluster) {
658		printf(
659		"Next free cluster in FSInfo (%lu) exceeds maxcluster (%lu)\n",
660		    pmp->pm_nxtfree, pmp->pm_maxcluster);
661		error = EINVAL;
662		goto error_exit;
663	}
664
665	/*
666	 * Allocate memory for the bitmap of allocated clusters, and then
667	 * fill it in.
668	 */
669	pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS)
670				  * sizeof(*pmp->pm_inusemap),
671				  M_MSDOSFSFAT, M_WAITOK);
672
673	/*
674	 * fillinusemap() needs pm_devvp.
675	 */
676	pmp->pm_devvp = devvp;
677
678	/*
679	 * Have the inuse map filled in.
680	 */
681	if ((error = fillinusemap(pmp)) != 0)
682		goto error_exit;
683
684	/*
685	 * If they want fat updates to be synchronous then let them suffer
686	 * the performance degradation in exchange for the on disk copy of
687	 * the fat being correct just about all the time.  I suppose this
688	 * would be a good thing to turn on if the kernel is still flakey.
689	 */
690	if (mp->mnt_flag & MNT_SYNCHRONOUS)
691		pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
692
693	/*
694	 * Finish up.
695	 */
696	if (ronly)
697		pmp->pm_flags |= MSDOSFSMNT_RONLY;
698	else {
699		/* Mark the volume dirty while it is mounted read/write. */
700		if ((error = markvoldirty(pmp, 1)) != 0)
701			goto error_exit;
702		pmp->pm_fmod = 1;
703	}
704	mp->mnt_data = (qaddr_t) pmp;
705	mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
706	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
707	mp->mnt_flag |= MNT_LOCAL;
708
709#ifdef MSDOSFS_LARGE
710	msdosfs_fileno_init(mp);
711#endif
712
713	return 0;
714
715error_exit:
716	if (bp)
717		brelse(bp);
718	if (cp != NULL) {
719		DROP_GIANT();
720		g_topology_lock();
721		g_vfs_close(cp, td);
722		g_topology_unlock();
723		PICKUP_GIANT();
724	}
725	if (pmp) {
726		if (pmp->pm_inusemap)
727			free(pmp->pm_inusemap, M_MSDOSFSFAT);
728		free(pmp, M_MSDOSFSMNT);
729		mp->mnt_data = (qaddr_t)0;
730	}
731	return (error);
732}
733
734/*
735 * Unmount the filesystem described by mp.
736 */
737static int
738msdosfs_unmount(mp, mntflags, td)
739	struct mount *mp;
740	int mntflags;
741	struct thread *td;
742{
743	struct msdosfsmount *pmp;
744	int error, flags;
745
746	flags = 0;
747	if (mntflags & MNT_FORCE)
748		flags |= FORCECLOSE;
749	error = vflush(mp, 0, flags, td);
750	if (error)
751		return error;
752	pmp = VFSTOMSDOSFS(mp);
753	if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) {
754		if (pmp->pm_w2u)
755			msdosfs_iconv->close(pmp->pm_w2u);
756		if (pmp->pm_u2w)
757			msdosfs_iconv->close(pmp->pm_u2w);
758		if (pmp->pm_d2u)
759			msdosfs_iconv->close(pmp->pm_d2u);
760		if (pmp->pm_u2d)
761			msdosfs_iconv->close(pmp->pm_u2d);
762	}
763
764	/* If the volume was mounted read/write, mark it clean now. */
765	if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) {
766		error = markvoldirty(pmp, 0);
767		if (error && (flags & FORCECLOSE) == 0)
768			return (error);
769	}
770#ifdef MSDOSFS_DEBUG
771	{
772		struct vnode *vp = pmp->pm_devvp;
773
774		VI_LOCK(vp);
775		vn_printf(vp,
776		    "msdosfs_umount(): just before calling VOP_CLOSE()\n");
777		printf("freef %p, freeb %p, mount %p\n",
778		    TAILQ_NEXT(vp, v_freelist), vp->v_freelist.tqe_prev,
779		    vp->v_mount);
780		printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n",
781		    TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd),
782		    TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd),
783		    vp->v_bufobj.bo_numoutput, vp->v_type);
784		VI_UNLOCK(vp);
785	}
786#endif
787	DROP_GIANT();
788	g_topology_lock();
789	g_vfs_close(pmp->pm_cp, td);
790	g_topology_unlock();
791	PICKUP_GIANT();
792	vrele(pmp->pm_devvp);
793	free(pmp->pm_inusemap, M_MSDOSFSFAT);
794#ifdef MSDOSFS_LARGE
795	msdosfs_fileno_free(mp);
796#endif
797	free(pmp, M_MSDOSFSMNT);
798	mp->mnt_data = (qaddr_t)0;
799	mp->mnt_flag &= ~MNT_LOCAL;
800	return (error);
801}
802
803static int
804msdosfs_root(mp, flags, vpp, td)
805	struct mount *mp;
806	int flags;
807	struct vnode **vpp;
808	struct thread *td;
809{
810	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
811	struct denode *ndep;
812	int error;
813
814#ifdef MSDOSFS_DEBUG
815	printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp);
816#endif
817	error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep);
818	if (error)
819		return (error);
820	*vpp = DETOV(ndep);
821	return (0);
822}
823
824static int
825msdosfs_statfs(mp, sbp, td)
826	struct mount *mp;
827	struct statfs *sbp;
828	struct thread *td;
829{
830	struct msdosfsmount *pmp;
831
832	pmp = VFSTOMSDOSFS(mp);
833	sbp->f_bsize = pmp->pm_bpcluster;
834	sbp->f_iosize = pmp->pm_bpcluster;
835	sbp->f_blocks = pmp->pm_maxcluster + 1;
836	sbp->f_bfree = pmp->pm_freeclustercount;
837	sbp->f_bavail = pmp->pm_freeclustercount;
838	sbp->f_files = pmp->pm_RootDirEnts;			/* XXX */
839	sbp->f_ffree = 0;	/* what to put in here? */
840	return (0);
841}
842
843static int
844msdosfs_sync(mp, waitfor, td)
845	struct mount *mp;
846	int waitfor;
847	struct thread *td;
848{
849	struct vnode *vp, *nvp;
850	struct denode *dep;
851	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
852	int error, allerror = 0;
853
854	/*
855	 * If we ever switch to not updating all of the fats all the time,
856	 * this would be the place to update them from the first one.
857	 */
858	if (pmp->pm_fmod != 0) {
859		if (pmp->pm_flags & MSDOSFSMNT_RONLY)
860			panic("msdosfs_sync: rofs mod");
861		else {
862			/* update fats here */
863		}
864	}
865	/*
866	 * Write back each (modified) denode.
867	 */
868	MNT_ILOCK(mp);
869loop:
870	MNT_VNODE_FOREACH(vp, mp, nvp) {
871		VI_LOCK(vp);
872		if (vp->v_type == VNON || (vp->v_iflag & VI_DOOMED)) {
873			VI_UNLOCK(vp);
874			continue;
875		}
876		MNT_IUNLOCK(mp);
877		dep = VTODE(vp);
878		if ((dep->de_flag &
879		    (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 &&
880		    (vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
881		    waitfor == MNT_LAZY)) {
882			VI_UNLOCK(vp);
883			MNT_ILOCK(mp);
884			continue;
885		}
886		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
887		if (error) {
888			MNT_ILOCK(mp);
889			if (error == ENOENT)
890				goto loop;
891			continue;
892		}
893		error = VOP_FSYNC(vp, waitfor, td);
894		if (error)
895			allerror = error;
896		VOP_UNLOCK(vp, 0, td);
897		vrele(vp);
898		MNT_ILOCK(mp);
899	}
900	MNT_IUNLOCK(mp);
901
902	/*
903	 * Flush filesystem control info.
904	 */
905	if (waitfor != MNT_LAZY) {
906		vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY, td);
907		error = VOP_FSYNC(pmp->pm_devvp, waitfor, td);
908		if (error)
909			allerror = error;
910		VOP_UNLOCK(pmp->pm_devvp, 0, td);
911	}
912	return (allerror);
913}
914
915static int
916msdosfs_fhtovp(mp, fhp, vpp)
917	struct mount *mp;
918	struct fid *fhp;
919	struct vnode **vpp;
920{
921	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
922	struct defid *defhp = (struct defid *) fhp;
923	struct denode *dep;
924	int error;
925
926	error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep);
927	if (error) {
928		*vpp = NULLVP;
929		return (error);
930	}
931	*vpp = DETOV(dep);
932	vnode_create_vobject(*vpp, dep->de_FileSize, curthread);
933	return (0);
934}
935
936static int
937msdosfs_vptofh(vp, fhp)
938	struct vnode *vp;
939	struct fid *fhp;
940{
941	struct denode *dep;
942	struct defid *defhp;
943
944	dep = VTODE(vp);
945	defhp = (struct defid *)fhp;
946	defhp->defid_len = sizeof(struct defid);
947	defhp->defid_dirclust = dep->de_dirclust;
948	defhp->defid_dirofs = dep->de_diroffset;
949	/* defhp->defid_gen = dep->de_gen; */
950	return (0);
951}
952
953static struct vfsops msdosfs_vfsops = {
954	.vfs_fhtovp =		msdosfs_fhtovp,
955	.vfs_mount =		msdosfs_mount,
956	.vfs_cmount =		msdosfs_cmount,
957	.vfs_root =		msdosfs_root,
958	.vfs_statfs =		msdosfs_statfs,
959	.vfs_sync =		msdosfs_sync,
960	.vfs_unmount =		msdosfs_unmount,
961	.vfs_vptofh =		msdosfs_vptofh,
962};
963
964VFS_SET(msdosfs_vfsops, msdosfs, 0);
965MODULE_VERSION(msdosfs, 1);
966