msdosfs_vfsops.c revision 33765
1/*	$Id: msdosfs_vfsops.c,v 1.26 1998/02/23 09:59:08 ache Exp $ */
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/namei.h>
54#include <sys/proc.h>
55#include <sys/kernel.h>
56#include <sys/vnode.h>
57#include <miscfs/specfs/specdev.h> /* XXX */	/* defines v_rdev */
58#include <sys/mount.h>
59#include <sys/buf.h>
60#include <sys/fcntl.h>
61#include <sys/malloc.h>
62#include <sys/stat.h> 				/* defines ALLPERMS */
63
64#include <msdosfs/bpb.h>
65#include <msdosfs/bootsect.h>
66#include <msdosfs/direntry.h>
67#include <msdosfs/denode.h>
68#include <msdosfs/msdosfsmount.h>
69#include <msdosfs/fat.h>
70
71MALLOC_DEFINE(M_MSDOSFSMNT, "MSDOSFS mount", "MSDOSFS mount structure");
72static MALLOC_DEFINE(M_MSDOSFSFAT, "MSDOSFS FAT", "MSDOSFS file allocation table");
73
74static int	update_mp __P((struct mount *mp, struct msdosfs_args *argp));
75static int	mountmsdosfs __P((struct vnode *devvp, struct mount *mp,
76				  struct proc *p, struct msdosfs_args *argp));
77static int	msdosfs_fhtovp __P((struct mount *, struct fid *,
78				    struct sockaddr *, struct vnode **, int *,
79				    struct ucred **));
80static int	msdosfs_mount __P((struct mount *, char *, caddr_t,
81				   struct nameidata *, struct proc *));
82static int	msdosfs_quotactl __P((struct mount *, int, uid_t, caddr_t,
83				      struct proc *));
84static int	msdosfs_root __P((struct mount *, struct vnode **));
85static int	msdosfs_start __P((struct mount *, int, struct proc *));
86static int	msdosfs_statfs __P((struct mount *, struct statfs *,
87				    struct proc *));
88static int	msdosfs_sync __P((struct mount *, int, struct ucred *,
89				  struct proc *));
90static int	msdosfs_unmount __P((struct mount *, int, struct proc *));
91static int	msdosfs_vget __P((struct mount *mp, ino_t ino,
92				  struct vnode **vpp));
93static int	msdosfs_vptofh __P((struct vnode *, struct fid *));
94
95static int
96update_mp(mp, argp)
97	struct mount *mp;
98	struct msdosfs_args *argp;
99{
100	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
101	int error;
102
103	pmp->pm_gid = argp->gid;
104	pmp->pm_uid = argp->uid;
105	pmp->pm_mask = argp->mask & ALLPERMS;
106	pmp->pm_flags |= argp->flags & MSDOSFSMNT_MNTOPT;
107	if (pmp->pm_flags & MSDOSFSMNT_U2WTABLE)
108		bcopy(argp->u2w, pmp->pm_u2w, sizeof(pmp->pm_u2w));
109	if (pmp->pm_flags & MSDOSFSMNT_ULTABLE)
110		bcopy(argp->ul, pmp->pm_ul, sizeof(pmp->pm_ul));
111
112#ifndef __FreeBSD__
113	/*
114	 * GEMDOS knows nothing (yet) about win95
115	 */
116	if (pmp->pm_flags & MSDOSFSMNT_GEMDOSFS)
117		pmp->pm_flags |= MSDOSFSMNT_NOWIN95;
118#endif
119
120	if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
121		pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
122	else if (!(pmp->pm_flags &
123	    (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
124		struct vnode *rootvp;
125
126		/*
127		 * Try to divine whether to support Win'95 long filenames
128		 */
129		if (FAT32(pmp))
130			pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
131		else {
132			if ((error = msdosfs_root(mp, &rootvp)) != 0)
133				return error;
134			pmp->pm_flags |= findwin95(VTODE(rootvp))
135				? MSDOSFSMNT_LONGNAME
136					: MSDOSFSMNT_SHORTNAME;
137			vput(rootvp);
138		}
139	}
140	return 0;
141}
142
143#ifndef __FreeBSD__
144int
145msdosfs_mountroot()
146{
147	register struct mount *mp;
148	struct proc *p = curproc;	/* XXX */
149	size_t size;
150	int error;
151	struct msdosfs_args args;
152
153	if (root_device->dv_class != DV_DISK)
154		return (ENODEV);
155
156	/*
157	 * Get vnodes for swapdev and rootdev.
158	 */
159	if (bdevvp(rootdev, &rootvp))
160		panic("msdosfs_mountroot: can't setup rootvp");
161
162	mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK);
163	bzero((char *)mp, (u_long)sizeof(struct mount));
164	mp->mnt_op = &msdosfs_vfsops;
165	mp->mnt_flag = 0;
166	LIST_INIT(&mp->mnt_vnodelist);
167
168	args.flags = 0;
169	args.uid = 0;
170	args.gid = 0;
171	args.mask = 0777;
172
173	if ((error = mountmsdosfs(rootvp, mp, p, &args)) != 0) {
174		free(mp, M_MOUNT);
175		return (error);
176	}
177
178	if ((error = update_mp(mp, &args)) != 0) {
179		(void)msdosfs_unmount(mp, 0, p);
180		free(mp, M_MOUNT);
181		return (error);
182	}
183
184	if ((error = vfs_lock(mp)) != 0) {
185		(void)msdosfs_unmount(mp, 0, p);
186		free(mp, M_MOUNT);
187		return (error);
188	}
189
190	CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
191	mp->mnt_vnodecovered = NULLVP;
192	(void) copystr("/", mp->mnt_stat.f_mntonname, MNAMELEN - 1,
193	    &size);
194	bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
195	(void) copystr(ROOTNAME, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
196	    &size);
197	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
198	(void)msdosfs_statfs(mp, &mp->mnt_stat, p);
199	vfs_unlock(mp);
200	return (0);
201}
202#endif
203
204/*
205 * mp - path - addr in user space of mount point (ie /usr or whatever)
206 * data - addr in user space of mount params including the name of the block
207 * special file to treat as a filesystem.
208 */
209static int
210msdosfs_mount(mp, path, data, ndp, p)
211	struct mount *mp;
212	char *path;
213	caddr_t data;
214	struct nameidata *ndp;
215	struct proc *p;
216{
217	struct vnode *devvp;	  /* vnode for blk device to mount */
218	struct msdosfs_args args; /* will hold data from mount request */
219	/* msdosfs specific mount control block */
220	struct msdosfsmount *pmp = NULL;
221	size_t size;
222	int error, flags;
223	mode_t accessmode;
224
225	error = copyin(data, (caddr_t)&args, sizeof(struct msdosfs_args));
226	if (error)
227		return (error);
228	if (args.magic != MSDOSFS_ARGSMAGIC) {
229		printf("Old mount_msdosfs, flags=%d\n", args.flags);
230		args.flags = 0;
231	}
232	/*
233	 * If updating, check whether changing from read-only to
234	 * read/write; if there is no device name, that's all we do.
235	 */
236	if (mp->mnt_flag & MNT_UPDATE) {
237		pmp = VFSTOMSDOSFS(mp);
238		error = 0;
239		if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && (mp->mnt_flag & MNT_RDONLY)) {
240			flags = WRITECLOSE;
241			if (mp->mnt_flag & MNT_FORCE)
242				flags |= FORCECLOSE;
243			error = vflush(mp, NULLVP, flags);
244		}
245		if (!error && (mp->mnt_flag & MNT_RELOAD))
246			/* not yet implemented */
247			error = EOPNOTSUPP;
248		if (error)
249			return (error);
250		if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
251			/*
252			 * If upgrade to read-write by non-root, then verify
253			 * that user has necessary permissions on the device.
254			 */
255			if (p->p_ucred->cr_uid != 0) {
256				devvp = pmp->pm_devvp;
257				vn_lock(devvp, LK_EXCLUSIVE, p);
258				error = VOP_ACCESS(devvp, VREAD | VWRITE,
259						   p->p_ucred, p);
260				if (error) {
261					VOP_UNLOCK(devvp, 0, p);
262					return (error);
263				}
264				VOP_UNLOCK(devvp, 0, p);
265			}
266			pmp->pm_flags &= ~MSDOSFSMNT_RONLY;
267		}
268		if (args.fspec == 0) {
269#ifdef	__notyet__		/* doesn't work correctly with current mountd	XXX */
270			if (args.flags & MSDOSFSMNT_MNTOPT) {
271				pmp->pm_flags &= ~MSDOSFSMNT_MNTOPT;
272				pmp->pm_flags |= args.flags & MSDOSFSMNT_MNTOPT;
273				if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
274					pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
275			}
276#endif
277			/*
278			 * Process export requests.
279			 */
280			return (vfs_export(mp, &pmp->pm_export, &args.export));
281		}
282	}
283	/*
284	 * Not an update, or updating the name: look up the name
285	 * and verify that it refers to a sensible block device.
286	 */
287	NDINIT(ndp, LOOKUP, FOLLOW, UIO_USERSPACE, args.fspec, p);
288	error = namei(ndp);
289	if (error)
290		return (error);
291	devvp = ndp->ni_vp;
292
293	if (devvp->v_type != VBLK) {
294		vrele(devvp);
295		return (ENOTBLK);
296	}
297	if (major(devvp->v_rdev) >= nblkdev) {
298		vrele(devvp);
299		return (ENXIO);
300	}
301	/*
302	 * If mount by non-root, then verify that user has necessary
303	 * permissions on the device.
304	 */
305	if (p->p_ucred->cr_uid != 0) {
306		accessmode = VREAD;
307		if ((mp->mnt_flag & MNT_RDONLY) == 0)
308			accessmode |= VWRITE;
309		vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
310		error = VOP_ACCESS(devvp, accessmode, p->p_ucred, p);
311		if (error) {
312			vput(devvp);
313			return (error);
314		}
315		VOP_UNLOCK(devvp, 0, p);
316	}
317	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
318		error = mountmsdosfs(devvp, mp, p, &args);
319#ifdef MSDOSFS_DEBUG		/* only needed for the printf below */
320		pmp = VFSTOMSDOSFS(mp);
321#endif
322	} else {
323		if (devvp != pmp->pm_devvp)
324			error = EINVAL;	/* XXX needs translation */
325		else
326			vrele(devvp);
327	}
328	if (error) {
329		vrele(devvp);
330		return (error);
331	}
332
333	error = update_mp(mp, &args);
334	if (error) {
335		msdosfs_unmount(mp, MNT_FORCE, p);
336		return error;
337	}
338
339	(void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
340	bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
341	(void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
342	    &size);
343	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
344	(void) msdosfs_statfs(mp, &mp->mnt_stat, p);
345#ifdef MSDOSFS_DEBUG
346	printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap);
347#endif
348	return (0);
349}
350
351static int
352mountmsdosfs(devvp, mp, p, argp)
353	struct vnode *devvp;
354	struct mount *mp;
355	struct proc *p;
356	struct msdosfs_args *argp;
357{
358	struct msdosfsmount *pmp;
359	struct buf *bp;
360	dev_t dev = devvp->v_rdev;
361#ifndef __FreeBSD__
362	struct partinfo dpart;
363#endif
364	union bootsector *bsp;
365	struct byte_bpb33 *b33;
366	struct byte_bpb50 *b50;
367#ifdef	PC98
368	u_int	pc98_wrk;
369	u_int	Phy_Sector_Size;
370#endif
371	struct byte_bpb710 *b710;
372	u_int8_t SecPerClust;
373	int	ronly, error;
374	int	bsize = 0, dtype = 0, tmp;
375
376	/*
377	 * Disallow multiple mounts of the same device.
378	 * Disallow mounting of a device that is currently in use
379	 * (except for root, which might share swap device for miniroot).
380	 * Flush out any old buffers remaining from a previous use.
381	 */
382	error = vfs_mountedon(devvp);
383	if (error)
384		return (error);
385	if (vcount(devvp) > 1 && devvp != rootvp)
386		return (EBUSY);
387	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
388	error = vinvalbuf(devvp, V_SAVE, p->p_ucred, p, 0, 0);
389	VOP_UNLOCK(devvp, 0, p);
390	if (error)
391		return (error);
392
393	ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
394	error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, FSCRED, p);
395	if (error)
396		return (error);
397
398	bp  = NULL; /* both used in error_exit */
399	pmp = NULL;
400
401#ifndef __FreeBSD__
402	if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
403		/*
404	 	 * We need the disklabel to calculate the size of a FAT entry
405		 * later on. Also make sure the partition contains a filesystem
406		 * of type FS_MSDOS. This doesn't work for floppies, so we have
407		 * to check for them too.
408	 	 *
409	 	 * At least some parts of the msdos fs driver seem to assume
410		 * that the size of a disk block will always be 512 bytes.
411		 * Let's check it...
412		 */
413		error = VOP_IOCTL(devvp, DIOCGPART, (caddr_t)&dpart,
414				  FREAD, NOCRED, p);
415		if (error)
416			goto error_exit;
417		tmp   = dpart.part->p_fstype;
418		dtype = dpart.disklab->d_type;
419		bsize = dpart.disklab->d_secsize;
420		if (bsize != 512 || (dtype!=DTYPE_FLOPPY && tmp!=FS_MSDOS)) {
421			error = EINVAL;
422			goto error_exit;
423		}
424	}
425#endif
426
427	/*
428	 * Read the boot sector of the filesystem, and then check the
429	 * boot signature.  If not a dos boot sector then error out.
430	 */
431#ifdef	PC98
432	devvp->v_flag &= 0xffff;
433	error = bread(devvp, 0, 1024, NOCRED, &bp);
434#else
435	error = bread(devvp, 0, 512, NOCRED, &bp);
436#endif
437	if (error)
438		goto error_exit;
439	bp->b_flags |= B_AGE;
440	bsp = (union bootsector *)bp->b_data;
441	b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
442	b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
443	b710 = (struct byte_bpb710 *)bsp->bs710.bsPBP;
444
445#ifndef __FreeBSD__
446	if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) {
447#endif
448#ifdef PC98
449		if ((bsp->bs50.bsBootSectSig0 != BOOTSIG0
450		    || bsp->bs50.bsBootSectSig1 != BOOTSIG1)
451		    && (bsp->bs50.bsBootSectSig0 != 0       /* PC98 DOS 3.3x */
452		    || bsp->bs50.bsBootSectSig1 != 0)
453		    && (bsp->bs50.bsBootSectSig0 != 0x90    /* PC98 DOS 5.0  */
454		    || bsp->bs50.bsBootSectSig1 != 0x3d)
455		    && (bsp->bs50.bsBootSectSig0 != 0x46    /* PC98 DOS 3.3B */
456		    || bsp->bs50.bsBootSectSig1 != 0xfa)) {
457#else
458		if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
459		    || bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
460#endif
461			error = EINVAL;
462			goto error_exit;
463		}
464#ifndef __FreeBSD__
465	}
466#endif
467
468	pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK);
469	bzero((caddr_t)pmp, sizeof *pmp);
470	pmp->pm_mountp = mp;
471
472	/*
473	 * Compute several useful quantities from the bpb in the
474	 * bootsector.  Copy in the dos 5 variant of the bpb then fix up
475	 * the fields that are different between dos 5 and dos 3.3.
476	 */
477	SecPerClust = b50->bpbSecPerClust;
478	pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
479	pmp->pm_ResSectors = getushort(b50->bpbResSectors);
480	pmp->pm_FATs = b50->bpbFATs;
481	pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
482	pmp->pm_Sectors = getushort(b50->bpbSectors);
483	pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
484	pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
485	pmp->pm_Heads = getushort(b50->bpbHeads);
486	pmp->pm_Media = b50->bpbMedia;
487
488#ifndef __FreeBSD__
489	if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) {
490#endif
491		/* XXX - We should probably check more values here */
492		if (!pmp->pm_BytesPerSec || !SecPerClust
493			|| !pmp->pm_Heads || pmp->pm_Heads > 255
494#ifdef PC98
495	    		|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 255) {
496#else
497			|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) {
498#endif
499			error = EINVAL;
500			goto error_exit;
501		}
502#ifndef __FreeBSD__
503	}
504#endif
505
506	if (pmp->pm_Sectors == 0) {
507		pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
508		pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
509	} else {
510		pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
511		pmp->pm_HugeSectors = pmp->pm_Sectors;
512	}
513#ifdef	PC98	/* for PC98		added Satoshi Yasuda	*/
514	Phy_Sector_Size = 512;
515	if ((devvp->v_rdev>>8) == 2) {	/* floppy check */
516		if (((devvp->v_rdev&077) == 2) && (pmp->pm_HugeSectors == 1232)) {
517				Phy_Sector_Size = 1024;	/* 2HD */
518				/*
519				 * 1024byte/sector support
520				 */
521				devvp->v_flag |= 0x10000;
522		} else {
523			if ((((devvp->v_rdev&077) == 3)	/* 2DD 8 or 9 sector */
524				&& (pmp->pm_HugeSectors == 1440)) /* 9 sector */
525				|| (((devvp->v_rdev&077) == 4)
526				&& (pmp->pm_HugeSectors == 1280)) /* 8 sector */
527				|| (((devvp->v_rdev&077) == 5)
528				&& (pmp->pm_HugeSectors == 2880))) { /* 1.44M */
529					Phy_Sector_Size = 512;
530			} else {
531				if (((devvp->v_rdev&077) != 1)
532				    && ((devvp->v_rdev&077) != 0)) { /* 2HC */
533					error = EINVAL;
534					goto error_exit;
535				}
536			}
537		}
538	}
539	pc98_wrk = pmp->pm_BytesPerSec / Phy_Sector_Size;
540	pmp->pm_BytesPerSec = Phy_Sector_Size;
541	SecPerClust = SecPerClust * pc98_wrk;
542	pmp->pm_HugeSectors = pmp->pm_HugeSectors * pc98_wrk;
543	pmp->pm_ResSectors = pmp->pm_ResSectors * pc98_wrk;
544	pmp->pm_FATsecs = pmp->pm_FATsecs * pc98_wrk;
545	pmp->pm_SecPerTrack = pmp->pm_SecPerTrack * pc98_wrk;
546	pmp->pm_HiddenSects = pmp->pm_HiddenSects * pc98_wrk;
547#endif			/*						*/
548	if (pmp->pm_HugeSectors > 0xffffffff / pmp->pm_BytesPerSec + 1) {
549		/*
550		 * We cannot deal currently with this size of disk
551		 * due to fileid limitations (see msdosfs_getattr and
552		 * msdosfs_readdir)
553		 */
554		error = EINVAL;
555		goto error_exit;
556	}
557
558	if (pmp->pm_RootDirEnts == 0) {
559		if (bsp->bs710.bsBootSectSig2 != BOOTSIG2
560		    || bsp->bs710.bsBootSectSig3 != BOOTSIG3
561		    || pmp->pm_Sectors
562		    || pmp->pm_FATsecs
563		    || getushort(b710->bpbFSVers)) {
564			error = EINVAL;
565			goto error_exit;
566		}
567		pmp->pm_fatmask = FAT32_MASK;
568		pmp->pm_fatmult = 4;
569		pmp->pm_fatdiv = 1;
570		pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
571		if (getushort(b710->bpbExtFlags) & FATMIRROR)
572			pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
573		else
574			pmp->pm_flags |= MSDOSFS_FATMIRROR;
575	} else
576		pmp->pm_flags |= MSDOSFS_FATMIRROR;
577
578#ifndef __FreeBSD__
579	if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
580		if (FAT32(pmp)) {
581			/*
582			 * GEMDOS doesn't know fat32.
583			 */
584			error = EINVAL;
585			goto error_exit;
586		}
587
588		/*
589		 * Check a few values (could do some more):
590		 * - logical sector size: power of 2, >= block size
591		 * - sectors per cluster: power of 2, >= 1
592		 * - number of sectors:   >= 1, <= size of partition
593		 */
594		if ( (SecPerClust == 0)
595		  || (SecPerClust & (SecPerClust - 1))
596		  || (pmp->pm_BytesPerSec < bsize)
597		  || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
598		  || (pmp->pm_HugeSectors == 0)
599		  || (pmp->pm_HugeSectors * (pmp->pm_BytesPerSec / bsize)
600							> dpart.part->p_size)
601		   ) {
602			error = EINVAL;
603			goto error_exit;
604		}
605		/*
606		 * XXX - Many parts of the msdos fs driver seem to assume that
607		 * the number of bytes per logical sector (BytesPerSec) will
608		 * always be the same as the number of bytes per disk block
609		 * Let's pretend it is.
610		 */
611		tmp = pmp->pm_BytesPerSec / bsize;
612		pmp->pm_BytesPerSec  = bsize;
613		pmp->pm_HugeSectors *= tmp;
614		pmp->pm_HiddenSects *= tmp;
615		pmp->pm_ResSectors  *= tmp;
616		pmp->pm_Sectors     *= tmp;
617		pmp->pm_FATsecs     *= tmp;
618		SecPerClust         *= tmp;
619	}
620#endif
621	pmp->pm_fatblk = pmp->pm_ResSectors;
622	if (FAT32(pmp)) {
623		pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
624		pmp->pm_firstcluster = pmp->pm_fatblk
625			+ (pmp->pm_FATs * pmp->pm_FATsecs);
626		pmp->pm_fsinfo = getushort(b710->bpbFSInfo);
627	} else {
628		pmp->pm_rootdirblk = pmp->pm_fatblk +
629			(pmp->pm_FATs * pmp->pm_FATsecs);
630		pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry)
631				       + pmp->pm_BytesPerSec - 1)
632			/ pmp->pm_BytesPerSec;/* in sectors */
633		pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
634	}
635
636	pmp->pm_nmbrofclusters = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
637	    SecPerClust;
638	pmp->pm_maxcluster = pmp->pm_nmbrofclusters + 1;
639	pmp->pm_fatsize = pmp->pm_FATsecs * pmp->pm_BytesPerSec;
640
641#ifndef __FreeBSD__
642	if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
643		if ((pmp->pm_nmbrofclusters <= (0xff0 - 2))
644		      && ((dtype == DTYPE_FLOPPY) || ((dtype == DTYPE_VNODE)
645		      && ((pmp->pm_Heads == 1) || (pmp->pm_Heads == 2))))
646		    ) {
647			pmp->pm_fatmask = FAT12_MASK;
648			pmp->pm_fatmult = 3;
649			pmp->pm_fatdiv = 2;
650		} else {
651			pmp->pm_fatmask = FAT16_MASK;
652			pmp->pm_fatmult = 2;
653			pmp->pm_fatdiv = 1;
654		}
655	} else
656#endif
657	if (pmp->pm_fatmask == 0) {
658		if (pmp->pm_maxcluster
659		    <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
660			/*
661			 * This will usually be a floppy disk. This size makes
662			 * sure that one fat entry will not be split across
663			 * multiple blocks.
664			 */
665			pmp->pm_fatmask = FAT12_MASK;
666			pmp->pm_fatmult = 3;
667			pmp->pm_fatdiv = 2;
668		} else {
669			pmp->pm_fatmask = FAT16_MASK;
670			pmp->pm_fatmult = 2;
671			pmp->pm_fatdiv = 1;
672		}
673	}
674	if (FAT12(pmp))
675		pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec;
676	else
677		pmp->pm_fatblocksize = MAXBSIZE;
678
679	pmp->pm_fatblocksec = pmp->pm_fatblocksize / pmp->pm_BytesPerSec;
680	pmp->pm_bnshift = ffs(pmp->pm_BytesPerSec) - 1;
681
682	/*
683	 * Compute mask and shift value for isolating cluster relative byte
684	 * offsets and cluster numbers from a file offset.
685	 */
686	pmp->pm_bpcluster = SecPerClust * pmp->pm_BytesPerSec;
687	pmp->pm_crbomask = pmp->pm_bpcluster - 1;
688	pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
689
690	/*
691	 * Check for valid cluster size
692	 * must be a power of 2
693	 */
694	if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
695		error = EINVAL;
696		goto error_exit;
697	}
698
699	/*
700	 * Release the bootsector buffer.
701	 */
702	brelse(bp);
703	bp = NULL;
704
705	/*
706	 * Check FSInfo.
707	 */
708	if (pmp->pm_fsinfo) {
709		struct fsinfo *fp;
710
711		if ((error = bread(devvp, pmp->pm_fsinfo, 1024, NOCRED, &bp)) != 0)
712			goto error_exit;
713		fp = (struct fsinfo *)bp->b_data;
714		if (!bcmp(fp->fsisig1, "RRaA", 4)
715		    && !bcmp(fp->fsisig2, "rrAa", 4)
716		    && !bcmp(fp->fsisig3, "\0\0\125\252", 4)
717		    && !bcmp(fp->fsisig4, "\0\0\125\252", 4))
718			pmp->pm_nxtfree = getulong(fp->fsinxtfree);
719		else
720			pmp->pm_fsinfo = 0;
721		brelse(bp);
722		bp = NULL;
723	}
724
725	/*
726	 * Check and validate (or perhaps invalidate?) the fsinfo structure?		XXX
727	 */
728
729	/*
730	 * Allocate memory for the bitmap of allocated clusters, and then
731	 * fill it in.
732	 */
733	pmp->pm_inusemap = malloc(((pmp->pm_maxcluster + N_INUSEBITS - 1)
734				   / N_INUSEBITS)
735				  * sizeof(*pmp->pm_inusemap),
736				  M_MSDOSFSFAT, M_WAITOK);
737
738	/*
739	 * fillinusemap() needs pm_devvp.
740	 */
741	pmp->pm_dev = dev;
742	pmp->pm_devvp = devvp;
743
744	/*
745	 * Have the inuse map filled in.
746	 */
747	if ((error = fillinusemap(pmp)) != 0)
748		goto error_exit;
749
750	/*
751	 * If they want fat updates to be synchronous then let them suffer
752	 * the performance degradation in exchange for the on disk copy of
753	 * the fat being correct just about all the time.  I suppose this
754	 * would be a good thing to turn on if the kernel is still flakey.
755	 */
756	if (mp->mnt_flag & MNT_SYNCHRONOUS)
757		pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
758
759	/*
760	 * Finish up.
761	 */
762	if (ronly)
763		pmp->pm_flags |= MSDOSFSMNT_RONLY;
764	else
765		pmp->pm_fmod = 1;
766	mp->mnt_data = (qaddr_t) pmp;
767	mp->mnt_stat.f_fsid.val[0] = (long)dev;
768	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
769	mp->mnt_flag |= MNT_LOCAL;
770	devvp->v_specflags |= SI_MOUNTEDON;
771
772	return 0;
773
774error_exit:
775	if (bp)
776		brelse(bp);
777	(void) VOP_CLOSE(devvp, ronly ? FREAD : FREAD | FWRITE, NOCRED, p);
778	if (pmp) {
779		if (pmp->pm_inusemap)
780			free(pmp->pm_inusemap, M_MSDOSFSFAT);
781		free(pmp, M_MSDOSFSMNT);
782		mp->mnt_data = (qaddr_t)0;
783	}
784	return (error);
785}
786
787static int
788msdosfs_start(mp, flags, p)
789	struct mount *mp;
790	int flags;
791	struct proc *p;
792{
793
794	return (0);
795}
796
797/*
798 * Unmount the filesystem described by mp.
799 */
800static int
801msdosfs_unmount(mp, mntflags, p)
802	struct mount *mp;
803	int mntflags;
804	struct proc *p;
805{
806	struct msdosfsmount *pmp;
807	int error, flags;
808
809	flags = 0;
810	if (mntflags & MNT_FORCE)
811		flags |= FORCECLOSE;
812	error = vflush(mp, NULLVP, flags);
813	if (error)
814		return error;
815	pmp = VFSTOMSDOSFS(mp);
816	pmp->pm_devvp->v_specflags &= ~SI_MOUNTEDON;
817#ifdef MSDOSFS_DEBUG
818	{
819		struct vnode *vp = pmp->pm_devvp;
820
821		printf("msdosfs_umount(): just before calling VOP_CLOSE()\n");
822		printf("flag %08lx, usecount %d, writecount %d, holdcnt %ld\n",
823		    vp->v_flag, vp->v_usecount, vp->v_writecount, vp->v_holdcnt);
824		printf("lastr %d, id %lu, mount %p, op %p\n",
825		    vp->v_lastr, vp->v_id, vp->v_mount, vp->v_op);
826		printf("freef %p, freeb %p, mount %p\n",
827		    vp->v_freelist.tqe_next, vp->v_freelist.tqe_prev,
828		    vp->v_mount);
829		printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n",
830		    vp->v_cleanblkhd.lh_first,
831		    vp->v_dirtyblkhd.lh_first,
832		    vp->v_numoutput, vp->v_type);
833		printf("union %p, tag %d, data[0] %08x, data[1] %08x\n",
834		    vp->v_socket, vp->v_tag,
835		    ((u_int *)vp->v_data)[0],
836		    ((u_int *)vp->v_data)[1]);
837	}
838#endif
839	error = VOP_CLOSE(pmp->pm_devvp, (pmp->pm_flags&MSDOSFSMNT_RONLY) ? FREAD : FREAD | FWRITE,
840	    NOCRED, p);
841	vrele(pmp->pm_devvp);
842	free(pmp->pm_inusemap, M_MSDOSFSFAT);
843	free(pmp, M_MSDOSFSMNT);
844	mp->mnt_data = (qaddr_t)0;
845	mp->mnt_flag &= ~MNT_LOCAL;
846	return (error);
847}
848
849static int
850msdosfs_root(mp, vpp)
851	struct mount *mp;
852	struct vnode **vpp;
853{
854	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
855	struct denode *ndep;
856	int error;
857
858#ifdef MSDOSFS_DEBUG
859	printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp);
860#endif
861	error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep);
862	if (error)
863		return (error);
864	*vpp = DETOV(ndep);
865	return (0);
866}
867
868static int
869msdosfs_quotactl(mp, cmds, uid, arg, p)
870	struct mount *mp;
871	int cmds;
872	uid_t uid;
873	caddr_t arg;
874	struct proc *p;
875{
876	return EOPNOTSUPP;
877}
878
879static int
880msdosfs_statfs(mp, sbp, p)
881	struct mount *mp;
882	struct statfs *sbp;
883	struct proc *p;
884{
885	struct msdosfsmount *pmp;
886
887	pmp = VFSTOMSDOSFS(mp);
888	sbp->f_bsize = pmp->pm_bpcluster;
889	sbp->f_iosize = pmp->pm_bpcluster;
890	sbp->f_blocks = pmp->pm_nmbrofclusters;
891	sbp->f_bfree = pmp->pm_freeclustercount;
892	sbp->f_bavail = pmp->pm_freeclustercount;
893	sbp->f_files = pmp->pm_RootDirEnts;			/* XXX */
894	sbp->f_ffree = 0;	/* what to put in here? */
895	if (sbp != &mp->mnt_stat) {
896		sbp->f_type = mp->mnt_vfc->vfc_typenum;
897		bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
898		bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
899	}
900	strncpy(sbp->f_fstypename, mp->mnt_vfc->vfc_name, MFSNAMELEN);
901	return (0);
902}
903
904static int
905msdosfs_sync(mp, waitfor, cred, p)
906	struct mount *mp;
907	int waitfor;
908	struct ucred *cred;
909	struct proc *p;
910{
911	struct vnode *vp, *nvp;
912	struct denode *dep;
913	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
914	int error, allerror = 0;
915
916	/*
917	 * If we ever switch to not updating all of the fats all the time,
918	 * this would be the place to update them from the first one.
919	 */
920	if (pmp->pm_fmod != 0)
921		if (pmp->pm_flags & MSDOSFSMNT_RONLY)
922			panic("msdosfs_sync: rofs mod");
923		else {
924			/* update fats here */
925		}
926	/*
927	 * Write back each (modified) denode.
928	 */
929	simple_lock(&mntvnode_slock);
930loop:
931	for (vp = mp->mnt_vnodelist.lh_first;
932	     vp != NULL;
933	     vp = nvp) {
934		/*
935		 * If the vnode that we are about to sync is no longer
936		 * assoicated with this mount point, start over.
937		 */
938		if (vp->v_mount != mp)
939			goto loop;
940
941		simple_lock(&vp->v_interlock);
942		nvp = vp->v_mntvnodes.le_next;
943		dep = VTODE(vp);
944		if (vp->v_type == VNON || ((dep->de_flag &
945		    (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0)
946		    && vp->v_dirtyblkhd.lh_first == NULL) {
947			simple_unlock(&vp->v_interlock);
948			continue;
949		}
950		simple_unlock(&mntvnode_slock);
951		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, p);
952		if (error) {
953			simple_lock(&mntvnode_slock);
954			if (error == ENOENT)
955				goto loop;
956			continue;
957		}
958		error = VOP_FSYNC(vp, cred, waitfor, p);
959		if (error)
960			allerror = error;
961		VOP_UNLOCK(vp, 0, p);
962		vrele(vp);	/* done with this one	 */
963		simple_lock(&mntvnode_slock);
964	}
965	simple_unlock(&mntvnode_slock);
966
967	/*
968	 * Flush filesystem control info.
969	 */
970	error = VOP_FSYNC(pmp->pm_devvp, cred, waitfor, p);
971	if (error)
972		allerror = error;
973	return (allerror);
974}
975
976static int
977msdosfs_fhtovp(mp, fhp, nam, vpp, exflagsp, credanonp)
978	struct mount *mp;
979	struct fid *fhp;
980	struct sockaddr *nam;
981	struct vnode **vpp;
982	int *exflagsp;
983	struct ucred **credanonp;
984{
985	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
986	struct defid *defhp = (struct defid *) fhp;
987	struct denode *dep;
988	struct netcred *np;
989	int error;
990
991	np = vfs_export_lookup(mp, &pmp->pm_export, nam);
992	if (np == NULL)
993		return (EACCES);
994	error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep);
995	if (error) {
996		*vpp = NULLVP;
997		return (error);
998	}
999	*vpp = DETOV(dep);
1000	*exflagsp = np->netc_exflags;
1001	*credanonp = &np->netc_anon;
1002	return (0);
1003}
1004
1005static int
1006msdosfs_vptofh(vp, fhp)
1007	struct vnode *vp;
1008	struct fid *fhp;
1009{
1010	struct denode *dep;
1011	struct defid *defhp;
1012
1013	dep = VTODE(vp);
1014	defhp = (struct defid *)fhp;
1015	defhp->defid_len = sizeof(struct defid);
1016	defhp->defid_dirclust = dep->de_dirclust;
1017	defhp->defid_dirofs = dep->de_diroffset;
1018	/* defhp->defid_gen = dep->de_gen; */
1019	return (0);
1020}
1021
1022static int
1023msdosfs_vget(mp, ino, vpp)
1024	struct mount *mp;
1025	ino_t ino;
1026	struct vnode **vpp;
1027{
1028	return EOPNOTSUPP;
1029}
1030
1031static struct vfsops msdosfs_vfsops = {
1032	msdosfs_mount,
1033	msdosfs_start,
1034	msdosfs_unmount,
1035	msdosfs_root,
1036	msdosfs_quotactl,
1037	msdosfs_statfs,
1038	msdosfs_sync,
1039	msdosfs_vget,
1040	msdosfs_fhtovp,
1041	msdosfs_vptofh,
1042	msdosfs_init
1043};
1044
1045VFS_SET(msdosfs_vfsops, msdos, MOUNT_MSDOS, 0);
1046