msdosfs_vfsops.c revision 33548
1/*	$Id: msdosfs_vfsops.c,v 1.23 1997/11/12 05:42:19 julian 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
108#ifndef __FreeBSD__
109	/*
110	 * GEMDOS knows nothing (yet) about win95
111	 */
112	if (pmp->pm_flags & MSDOSFSMNT_GEMDOSFS)
113		pmp->pm_flags |= MSDOSFSMNT_NOWIN95;
114#endif
115
116	if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
117		pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
118	else if (!(pmp->pm_flags &
119	    (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
120		struct vnode *rootvp;
121
122		/*
123		 * Try to divine whether to support Win'95 long filenames
124		 */
125		if (FAT32(pmp))
126			pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
127		else {
128			if ((error = msdosfs_root(mp, &rootvp)) != 0)
129				return error;
130			pmp->pm_flags |= findwin95(VTODE(rootvp))
131				? MSDOSFSMNT_LONGNAME
132					: MSDOSFSMNT_SHORTNAME;
133			vput(rootvp);
134		}
135	}
136	return 0;
137}
138
139#ifndef __FreeBSD__
140int
141msdosfs_mountroot()
142{
143	register struct mount *mp;
144	struct proc *p = curproc;	/* XXX */
145	size_t size;
146	int error;
147	struct msdosfs_args args;
148
149	if (root_device->dv_class != DV_DISK)
150		return (ENODEV);
151
152	/*
153	 * Get vnodes for swapdev and rootdev.
154	 */
155	if (bdevvp(rootdev, &rootvp))
156		panic("msdosfs_mountroot: can't setup rootvp");
157
158	mp = malloc((u_long)sizeof(struct mount), M_MOUNT, M_WAITOK);
159	bzero((char *)mp, (u_long)sizeof(struct mount));
160	mp->mnt_op = &msdosfs_vfsops;
161	mp->mnt_flag = 0;
162	LIST_INIT(&mp->mnt_vnodelist);
163
164	args.flags = 0;
165	args.uid = 0;
166	args.gid = 0;
167	args.mask = 0777;
168
169	if ((error = mountmsdosfs(rootvp, mp, p, &args)) != 0) {
170		free(mp, M_MOUNT);
171		return (error);
172	}
173
174	if ((error = update_mp(mp, &args)) != 0) {
175		(void)msdosfs_unmount(mp, 0, p);
176		free(mp, M_MOUNT);
177		return (error);
178	}
179
180	if ((error = vfs_lock(mp)) != 0) {
181		(void)msdosfs_unmount(mp, 0, p);
182		free(mp, M_MOUNT);
183		return (error);
184	}
185
186	CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
187	mp->mnt_vnodecovered = NULLVP;
188	(void) copystr("/", mp->mnt_stat.f_mntonname, MNAMELEN - 1,
189	    &size);
190	bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
191	(void) copystr(ROOTNAME, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
192	    &size);
193	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
194	(void)msdosfs_statfs(mp, &mp->mnt_stat, p);
195	vfs_unlock(mp);
196	return (0);
197}
198#endif
199
200/*
201 * mp - path - addr in user space of mount point (ie /usr or whatever)
202 * data - addr in user space of mount params including the name of the block
203 * special file to treat as a filesystem.
204 */
205static int
206msdosfs_mount(mp, path, data, ndp, p)
207	struct mount *mp;
208	char *path;
209	caddr_t data;
210	struct nameidata *ndp;
211	struct proc *p;
212{
213	struct vnode *devvp;	  /* vnode for blk device to mount */
214	struct msdosfs_args args; /* will hold data from mount request */
215	/* msdosfs specific mount control block */
216	struct msdosfsmount *pmp = NULL;
217	size_t size;
218	int error, flags;
219	mode_t accessmode;
220
221	error = copyin(data, (caddr_t)&args, sizeof(struct msdosfs_args));
222	if (error)
223		return (error);
224	if (args.magic != MSDOSFS_ARGSMAGIC) {
225		printf("Old mount_msdosfs, flags=%d\n", args.flags);
226		args.flags = 0;
227	}
228	/*
229	 * If updating, check whether changing from read-only to
230	 * read/write; if there is no device name, that's all we do.
231	 */
232	if (mp->mnt_flag & MNT_UPDATE) {
233		pmp = VFSTOMSDOSFS(mp);
234		error = 0;
235		if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && (mp->mnt_flag & MNT_RDONLY)) {
236			flags = WRITECLOSE;
237			if (mp->mnt_flag & MNT_FORCE)
238				flags |= FORCECLOSE;
239			error = vflush(mp, NULLVP, flags);
240		}
241		if (!error && (mp->mnt_flag & MNT_RELOAD))
242			/* not yet implemented */
243			error = EOPNOTSUPP;
244		if (error)
245			return (error);
246		if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && (mp->mnt_kern_flag & MNTK_WANTRDWR)) {
247			/*
248			 * If upgrade to read-write by non-root, then verify
249			 * that user has necessary permissions on the device.
250			 */
251			if (p->p_ucred->cr_uid != 0) {
252				devvp = pmp->pm_devvp;
253				vn_lock(devvp, LK_EXCLUSIVE, p);
254				error = VOP_ACCESS(devvp, VREAD | VWRITE,
255						   p->p_ucred, p);
256				if (error) {
257					VOP_UNLOCK(devvp, 0, p);
258					return (error);
259				}
260				VOP_UNLOCK(devvp, 0, p);
261			}
262			pmp->pm_flags &= ~MSDOSFSMNT_RONLY;
263		}
264		if (args.fspec == 0) {
265#ifdef	__notyet__		/* doesn't work correctly with current mountd	XXX */
266			if (args.flags & MSDOSFSMNT_MNTOPT) {
267				pmp->pm_flags &= ~MSDOSFSMNT_MNTOPT;
268				pmp->pm_flags |= args.flags & MSDOSFSMNT_MNTOPT;
269				if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
270					pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
271			}
272#endif
273			/*
274			 * Process export requests.
275			 */
276			return (vfs_export(mp, &pmp->pm_export, &args.export));
277		}
278	}
279	/*
280	 * Not an update, or updating the name: look up the name
281	 * and verify that it refers to a sensible block device.
282	 */
283	NDINIT(ndp, LOOKUP, FOLLOW, UIO_USERSPACE, args.fspec, p);
284	error = namei(ndp);
285	if (error)
286		return (error);
287	devvp = ndp->ni_vp;
288
289	if (devvp->v_type != VBLK) {
290		vrele(devvp);
291		return (ENOTBLK);
292	}
293	if (major(devvp->v_rdev) >= nblkdev) {
294		vrele(devvp);
295		return (ENXIO);
296	}
297	/*
298	 * If mount by non-root, then verify that user has necessary
299	 * permissions on the device.
300	 */
301	if (p->p_ucred->cr_uid != 0) {
302		accessmode = VREAD;
303		if ((mp->mnt_flag & MNT_RDONLY) == 0)
304			accessmode |= VWRITE;
305		vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
306		error = VOP_ACCESS(devvp, accessmode, p->p_ucred, p);
307		if (error) {
308			vput(devvp);
309			return (error);
310		}
311		VOP_UNLOCK(devvp, 0, p);
312	}
313	if ((mp->mnt_flag & MNT_UPDATE) == 0) {
314		error = mountmsdosfs(devvp, mp, p, &args);
315#ifdef MSDOSFS_DEBUG		/* only needed for the printf below */
316		pmp = VFSTOMSDOSFS(mp);
317#endif
318	} else {
319		if (devvp != pmp->pm_devvp)
320			error = EINVAL;	/* XXX needs translation */
321		else
322			vrele(devvp);
323	}
324	if (error) {
325		vrele(devvp);
326		return (error);
327	}
328
329	error = update_mp(mp, &args);
330	if (error) {
331		msdosfs_unmount(mp, MNT_FORCE, p);
332		return error;
333	}
334
335	(void) copyinstr(path, mp->mnt_stat.f_mntonname, MNAMELEN - 1, &size);
336	bzero(mp->mnt_stat.f_mntonname + size, MNAMELEN - size);
337	(void) copyinstr(args.fspec, mp->mnt_stat.f_mntfromname, MNAMELEN - 1,
338	    &size);
339	bzero(mp->mnt_stat.f_mntfromname + size, MNAMELEN - size);
340	(void) msdosfs_statfs(mp, &mp->mnt_stat, p);
341#ifdef MSDOSFS_DEBUG
342	printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap);
343#endif
344	return (0);
345}
346
347static int
348mountmsdosfs(devvp, mp, p, argp)
349	struct vnode *devvp;
350	struct mount *mp;
351	struct proc *p;
352	struct msdosfs_args *argp;
353{
354	struct msdosfsmount *pmp;
355	struct buf *bp;
356	dev_t dev = devvp->v_rdev;
357#ifndef __FreeBSD__
358	struct partinfo dpart;
359#endif
360	union bootsector *bsp;
361	struct byte_bpb33 *b33;
362	struct byte_bpb50 *b50;
363#ifdef	PC98
364	u_int	pc98_wrk;
365	u_int	Phy_Sector_Size;
366#endif
367	struct byte_bpb710 *b710;
368	u_int8_t SecPerClust;
369	int	ronly, error;
370	int	bsize = 0, dtype = 0, tmp;
371
372	/*
373	 * Disallow multiple mounts of the same device.
374	 * Disallow mounting of a device that is currently in use
375	 * (except for root, which might share swap device for miniroot).
376	 * Flush out any old buffers remaining from a previous use.
377	 */
378	error = vfs_mountedon(devvp);
379	if (error)
380		return (error);
381	if (vcount(devvp) > 1 && devvp != rootvp)
382		return (EBUSY);
383	vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, p);
384	error = vinvalbuf(devvp, V_SAVE, p->p_ucred, p, 0, 0);
385	VOP_UNLOCK(devvp, 0, p);
386	if (error)
387		return (error);
388
389	ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
390	error = VOP_OPEN(devvp, ronly ? FREAD : FREAD|FWRITE, FSCRED, p);
391	if (error)
392		return (error);
393
394	bp  = NULL; /* both used in error_exit */
395	pmp = NULL;
396
397#ifndef __FreeBSD__
398	if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
399		/*
400	 	 * We need the disklabel to calculate the size of a FAT entry
401		 * later on. Also make sure the partition contains a filesystem
402		 * of type FS_MSDOS. This doesn't work for floppies, so we have
403		 * to check for them too.
404	 	 *
405	 	 * At least some parts of the msdos fs driver seem to assume
406		 * that the size of a disk block will always be 512 bytes.
407		 * Let's check it...
408		 */
409		error = VOP_IOCTL(devvp, DIOCGPART, (caddr_t)&dpart,
410				  FREAD, NOCRED, p);
411		if (error)
412			goto error_exit;
413		tmp   = dpart.part->p_fstype;
414		dtype = dpart.disklab->d_type;
415		bsize = dpart.disklab->d_secsize;
416		if (bsize != 512 || (dtype!=DTYPE_FLOPPY && tmp!=FS_MSDOS)) {
417			error = EINVAL;
418			goto error_exit;
419		}
420	}
421#endif
422
423	/*
424	 * Read the boot sector of the filesystem, and then check the
425	 * boot signature.  If not a dos boot sector then error out.
426	 */
427#ifdef	PC98
428	devvp->v_flag &= 0xffff;
429	error = bread(devvp, 0, 1024, NOCRED, &bp);
430#else
431	error = bread(devvp, 0, 512, NOCRED, &bp);
432#endif
433	if (error)
434		goto error_exit;
435	bp->b_flags |= B_AGE;
436	bsp = (union bootsector *)bp->b_data;
437	b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
438	b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
439	b710 = (struct byte_bpb710 *)bsp->bs710.bsPBP;
440
441#ifndef __FreeBSD__
442	if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) {
443#endif
444#ifdef PC98
445		if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
446		    || bsp->bs50.bsBootSectSig1 != BOOTSIG1
447		    && bsp->bs50.bsBootSectSig0 != 0	    /* PC98 DOS 3.3x */
448		    || bsp->bs50.bsBootSectSig1 != 0
449		    && bsp->bs50.bsBootSectSig0 != 0x90     /* PC98 DOS 5.0  */
450		    || bsp->bs50.bsBootSectSig1 != 0x3d
451		    && bsp->bs50.bsBootSectSig0 != 0x46     /* PC98 DOS 3.3B */
452		    || bsp->bs50.bsBootSectSig1 != 0xfa) {
453#else
454		if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
455		    || bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
456#endif
457			error = EINVAL;
458			goto error_exit;
459		}
460#ifndef __FreeBSD__
461	}
462#endif
463
464	pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK);
465	bzero((caddr_t)pmp, sizeof *pmp);
466	pmp->pm_mountp = mp;
467
468	/*
469	 * Compute several useful quantities from the bpb in the
470	 * bootsector.  Copy in the dos 5 variant of the bpb then fix up
471	 * the fields that are different between dos 5 and dos 3.3.
472	 */
473	SecPerClust = b50->bpbSecPerClust;
474	pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
475	pmp->pm_ResSectors = getushort(b50->bpbResSectors);
476	pmp->pm_FATs = b50->bpbFATs;
477	pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
478	pmp->pm_Sectors = getushort(b50->bpbSectors);
479	pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
480	pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
481	pmp->pm_Heads = getushort(b50->bpbHeads);
482	pmp->pm_Media = b50->bpbMedia;
483
484#ifndef __FreeBSD__
485	if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) {
486#endif
487		/* XXX - We should probably check more values here */
488		if (!pmp->pm_BytesPerSec || !SecPerClust
489			|| !pmp->pm_Heads || pmp->pm_Heads > 255
490#ifdef PC98
491	    		|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 255) {
492#else
493			|| !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) {
494#endif
495			error = EINVAL;
496			goto error_exit;
497		}
498#ifndef __FreeBSD__
499	}
500#endif
501
502	if (pmp->pm_Sectors == 0) {
503		pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
504		pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
505	} else {
506		pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
507		pmp->pm_HugeSectors = pmp->pm_Sectors;
508	}
509#ifdef	PC98	/* for PC98		added Satoshi Yasuda	*/
510	Phy_Sector_Size = 512;
511	if ((devvp->v_rdev>>8) == 2) {	/* floppy check */
512		if (((devvp->v_rdev&077) == 2) && (pmp->pm_HugeSectors == 1232)) {
513				Phy_Sector_Size = 1024;	/* 2HD */
514				/*
515				 * 1024byte/sector support
516				 */
517				devvp->v_flag |= 0x10000;
518		} else {
519			if ((((devvp->v_rdev&077) == 3)	/* 2DD 8 or 9 sector */
520				&& (pmp->pm_HugeSectors == 1440)) /* 9 sector */
521				|| (((devvp->v_rdev&077) == 4)
522				&& (pmp->pm_HugeSectors == 1280)) /* 8 sector */
523				|| (((devvp->v_rdev&077) == 5)
524				&& (pmp->pm_HugeSectors == 2880))) { /* 1.44M */
525					Phy_Sector_Size = 512;
526			} else {
527				if (((devvp->v_rdev&077) != 1)
528				    && ((devvp->v_rdev&077) != 0)) { /* 2HC */
529					error = EINVAL;
530					goto error_exit;
531				}
532			}
533		}
534	}
535	pc98_wrk = pmp->pm_BytesPerSec / Phy_Sector_Size;
536	pmp->pm_BytesPerSec = Phy_Sector_Size;
537	SecPerClust = SecPerClust * pc98_wrk;
538	pmp->pm_HugeSectors = pmp->pm_HugeSectors * pc98_wrk;
539	pmp->pm_ResSectors = pmp->pm_ResSectors * pc98_wrk;
540	pmp->pm_FATsecs = pmp->pm_FATsecs * pc98_wrk;
541	pmp->pm_SecPerTrack = pmp->pm_SecPerTrack * pc98_wrk;
542	pmp->pm_HiddenSects = pmp->pm_HiddenSects * pc98_wrk;
543#endif			/*						*/
544	if (pmp->pm_HugeSectors > 0xffffffff / pmp->pm_BytesPerSec + 1) {
545		/*
546		 * We cannot deal currently with this size of disk
547		 * due to fileid limitations (see msdosfs_getattr and
548		 * msdosfs_readdir)
549		 */
550		error = EINVAL;
551		goto error_exit;
552	}
553
554	if (pmp->pm_RootDirEnts == 0) {
555		if (bsp->bs710.bsBootSectSig2 != BOOTSIG2
556		    || bsp->bs710.bsBootSectSig3 != BOOTSIG3
557		    || pmp->pm_Sectors
558		    || pmp->pm_FATsecs
559		    || getushort(b710->bpbFSVers)) {
560			error = EINVAL;
561			goto error_exit;
562		}
563		pmp->pm_fatmask = FAT32_MASK;
564		pmp->pm_fatmult = 4;
565		pmp->pm_fatdiv = 1;
566		pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
567		if (getushort(b710->bpbExtFlags) & FATMIRROR)
568			pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
569		else
570			pmp->pm_flags |= MSDOSFS_FATMIRROR;
571	} else
572		pmp->pm_flags |= MSDOSFS_FATMIRROR;
573
574#ifndef __FreeBSD__
575	if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
576		if (FAT32(pmp)) {
577			/*
578			 * GEMDOS doesn't know fat32.
579			 */
580			error = EINVAL;
581			goto error_exit;
582		}
583
584		/*
585		 * Check a few values (could do some more):
586		 * - logical sector size: power of 2, >= block size
587		 * - sectors per cluster: power of 2, >= 1
588		 * - number of sectors:   >= 1, <= size of partition
589		 */
590		if ( (SecPerClust == 0)
591		  || (SecPerClust & (SecPerClust - 1))
592		  || (pmp->pm_BytesPerSec < bsize)
593		  || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
594		  || (pmp->pm_HugeSectors == 0)
595		  || (pmp->pm_HugeSectors * (pmp->pm_BytesPerSec / bsize)
596							> dpart.part->p_size)
597		   ) {
598			error = EINVAL;
599			goto error_exit;
600		}
601		/*
602		 * XXX - Many parts of the msdos fs driver seem to assume that
603		 * the number of bytes per logical sector (BytesPerSec) will
604		 * always be the same as the number of bytes per disk block
605		 * Let's pretend it is.
606		 */
607		tmp = pmp->pm_BytesPerSec / bsize;
608		pmp->pm_BytesPerSec  = bsize;
609		pmp->pm_HugeSectors *= tmp;
610		pmp->pm_HiddenSects *= tmp;
611		pmp->pm_ResSectors  *= tmp;
612		pmp->pm_Sectors     *= tmp;
613		pmp->pm_FATsecs     *= tmp;
614		SecPerClust         *= tmp;
615	}
616#endif
617	pmp->pm_fatblk = pmp->pm_ResSectors;
618	if (FAT32(pmp)) {
619		pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
620		pmp->pm_firstcluster = pmp->pm_fatblk
621			+ (pmp->pm_FATs * pmp->pm_FATsecs);
622		pmp->pm_fsinfo = getushort(b710->bpbFSInfo);
623	} else {
624		pmp->pm_rootdirblk = pmp->pm_fatblk +
625			(pmp->pm_FATs * pmp->pm_FATsecs);
626		pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry)
627				       + pmp->pm_BytesPerSec - 1)
628			/ pmp->pm_BytesPerSec;/* in sectors */
629		pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
630	}
631
632	pmp->pm_nmbrofclusters = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
633	    SecPerClust;
634	pmp->pm_maxcluster = pmp->pm_nmbrofclusters + 1;
635	pmp->pm_fatsize = pmp->pm_FATsecs * pmp->pm_BytesPerSec;
636
637#ifndef __FreeBSD__
638	if (argp->flags & MSDOSFSMNT_GEMDOSFS) {
639		if ((pmp->pm_nmbrofclusters <= (0xff0 - 2))
640		      && ((dtype == DTYPE_FLOPPY) || ((dtype == DTYPE_VNODE)
641		      && ((pmp->pm_Heads == 1) || (pmp->pm_Heads == 2))))
642		    ) {
643			pmp->pm_fatmask = FAT12_MASK;
644			pmp->pm_fatmult = 3;
645			pmp->pm_fatdiv = 2;
646		} else {
647			pmp->pm_fatmask = FAT16_MASK;
648			pmp->pm_fatmult = 2;
649			pmp->pm_fatdiv = 1;
650		}
651	} else
652#endif
653	if (pmp->pm_fatmask == 0) {
654		if (pmp->pm_maxcluster
655		    <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
656			/*
657			 * This will usually be a floppy disk. This size makes
658			 * sure that one fat entry will not be split across
659			 * multiple blocks.
660			 */
661			pmp->pm_fatmask = FAT12_MASK;
662			pmp->pm_fatmult = 3;
663			pmp->pm_fatdiv = 2;
664		} else {
665			pmp->pm_fatmask = FAT16_MASK;
666			pmp->pm_fatmult = 2;
667			pmp->pm_fatdiv = 1;
668		}
669	}
670	if (FAT12(pmp))
671		pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec;
672	else
673		pmp->pm_fatblocksize = MAXBSIZE;
674
675	pmp->pm_fatblocksec = pmp->pm_fatblocksize / pmp->pm_BytesPerSec;
676	pmp->pm_bnshift = ffs(pmp->pm_BytesPerSec) - 1;
677
678	/*
679	 * Compute mask and shift value for isolating cluster relative byte
680	 * offsets and cluster numbers from a file offset.
681	 */
682	pmp->pm_bpcluster = SecPerClust * pmp->pm_BytesPerSec;
683	pmp->pm_crbomask = pmp->pm_bpcluster - 1;
684	pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
685
686	/*
687	 * Check for valid cluster size
688	 * must be a power of 2
689	 */
690	if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
691		error = EINVAL;
692		goto error_exit;
693	}
694
695	/*
696	 * Release the bootsector buffer.
697	 */
698	brelse(bp);
699	bp = NULL;
700
701	/*
702	 * Check FSInfo.
703	 */
704	if (pmp->pm_fsinfo) {
705		struct fsinfo *fp;
706
707		if ((error = bread(devvp, pmp->pm_fsinfo, 1024, NOCRED, &bp)) != 0)
708			goto error_exit;
709		fp = (struct fsinfo *)bp->b_data;
710		if (!bcmp(fp->fsisig1, "RRaA", 4)
711		    && !bcmp(fp->fsisig2, "rrAa", 4)
712		    && !bcmp(fp->fsisig3, "\0\0\125\252", 4)
713		    && !bcmp(fp->fsisig4, "\0\0\125\252", 4))
714			pmp->pm_nxtfree = getulong(fp->fsinxtfree);
715		else
716			pmp->pm_fsinfo = 0;
717		brelse(bp);
718		bp = NULL;
719	}
720
721	/*
722	 * Check and validate (or perhaps invalidate?) the fsinfo structure?		XXX
723	 */
724
725	/*
726	 * Allocate memory for the bitmap of allocated clusters, and then
727	 * fill it in.
728	 */
729	pmp->pm_inusemap = malloc(((pmp->pm_maxcluster + N_INUSEBITS - 1)
730				   / N_INUSEBITS)
731				  * sizeof(*pmp->pm_inusemap),
732				  M_MSDOSFSFAT, M_WAITOK);
733
734	/*
735	 * fillinusemap() needs pm_devvp.
736	 */
737	pmp->pm_dev = dev;
738	pmp->pm_devvp = devvp;
739
740	/*
741	 * Have the inuse map filled in.
742	 */
743	if ((error = fillinusemap(pmp)) != 0)
744		goto error_exit;
745
746	/*
747	 * If they want fat updates to be synchronous then let them suffer
748	 * the performance degradation in exchange for the on disk copy of
749	 * the fat being correct just about all the time.  I suppose this
750	 * would be a good thing to turn on if the kernel is still flakey.
751	 */
752	if (mp->mnt_flag & MNT_SYNCHRONOUS)
753		pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
754
755	/*
756	 * Finish up.
757	 */
758	if (ronly)
759		pmp->pm_flags |= MSDOSFSMNT_RONLY;
760	else
761		pmp->pm_fmod = 1;
762	mp->mnt_data = (qaddr_t) pmp;
763	mp->mnt_stat.f_fsid.val[0] = (long)dev;
764	mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
765	mp->mnt_flag |= MNT_LOCAL;
766	devvp->v_specflags |= SI_MOUNTEDON;
767
768	return 0;
769
770error_exit:
771	if (bp)
772		brelse(bp);
773	(void) VOP_CLOSE(devvp, ronly ? FREAD : FREAD | FWRITE, NOCRED, p);
774	if (pmp) {
775		if (pmp->pm_inusemap)
776			free(pmp->pm_inusemap, M_MSDOSFSFAT);
777		free(pmp, M_MSDOSFSMNT);
778		mp->mnt_data = (qaddr_t)0;
779	}
780	return (error);
781}
782
783static int
784msdosfs_start(mp, flags, p)
785	struct mount *mp;
786	int flags;
787	struct proc *p;
788{
789
790	return (0);
791}
792
793/*
794 * Unmount the filesystem described by mp.
795 */
796static int
797msdosfs_unmount(mp, mntflags, p)
798	struct mount *mp;
799	int mntflags;
800	struct proc *p;
801{
802	struct msdosfsmount *pmp;
803	int error, flags;
804
805	flags = 0;
806	if (mntflags & MNT_FORCE)
807		flags |= FORCECLOSE;
808	error = vflush(mp, NULLVP, flags);
809	if (error)
810		return error;
811	pmp = VFSTOMSDOSFS(mp);
812	pmp->pm_devvp->v_specflags &= ~SI_MOUNTEDON;
813#ifdef MSDOSFS_DEBUG
814	{
815		struct vnode *vp = pmp->pm_devvp;
816
817		printf("msdosfs_umount(): just before calling VOP_CLOSE()\n");
818		printf("flag %08lx, usecount %d, writecount %d, holdcnt %ld\n",
819		    vp->v_flag, vp->v_usecount, vp->v_writecount, vp->v_holdcnt);
820		printf("lastr %d, id %lu, mount %p, op %p\n",
821		    vp->v_lastr, vp->v_id, vp->v_mount, vp->v_op);
822		printf("freef %p, freeb %p, mount %p\n",
823		    vp->v_freelist.tqe_next, vp->v_freelist.tqe_prev,
824		    vp->v_mount);
825		printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n",
826		    vp->v_cleanblkhd.lh_first,
827		    vp->v_dirtyblkhd.lh_first,
828		    vp->v_numoutput, vp->v_type);
829		printf("union %p, tag %d, data[0] %08x, data[1] %08x\n",
830		    vp->v_socket, vp->v_tag,
831		    ((u_int *)vp->v_data)[0],
832		    ((u_int *)vp->v_data)[1]);
833	}
834#endif
835	error = VOP_CLOSE(pmp->pm_devvp, (pmp->pm_flags&MSDOSFSMNT_RONLY) ? FREAD : FREAD | FWRITE,
836	    NOCRED, p);
837	vrele(pmp->pm_devvp);
838	free(pmp->pm_inusemap, M_MSDOSFSFAT);
839	free(pmp, M_MSDOSFSMNT);
840	mp->mnt_data = (qaddr_t)0;
841	mp->mnt_flag &= ~MNT_LOCAL;
842	return (error);
843}
844
845static int
846msdosfs_root(mp, vpp)
847	struct mount *mp;
848	struct vnode **vpp;
849{
850	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
851	struct denode *ndep;
852	int error;
853
854#ifdef MSDOSFS_DEBUG
855	printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp);
856#endif
857	error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep);
858	if (error)
859		return (error);
860	*vpp = DETOV(ndep);
861	return (0);
862}
863
864static int
865msdosfs_quotactl(mp, cmds, uid, arg, p)
866	struct mount *mp;
867	int cmds;
868	uid_t uid;
869	caddr_t arg;
870	struct proc *p;
871{
872	return EOPNOTSUPP;
873}
874
875static int
876msdosfs_statfs(mp, sbp, p)
877	struct mount *mp;
878	struct statfs *sbp;
879	struct proc *p;
880{
881	struct msdosfsmount *pmp;
882
883	pmp = VFSTOMSDOSFS(mp);
884	sbp->f_bsize = pmp->pm_bpcluster;
885	sbp->f_iosize = pmp->pm_bpcluster;
886	sbp->f_blocks = pmp->pm_nmbrofclusters;
887	sbp->f_bfree = pmp->pm_freeclustercount;
888	sbp->f_bavail = pmp->pm_freeclustercount;
889	sbp->f_files = pmp->pm_RootDirEnts;			/* XXX */
890	sbp->f_ffree = 0;	/* what to put in here? */
891	if (sbp != &mp->mnt_stat) {
892		sbp->f_type = mp->mnt_vfc->vfc_typenum;
893		bcopy(mp->mnt_stat.f_mntonname, sbp->f_mntonname, MNAMELEN);
894		bcopy(mp->mnt_stat.f_mntfromname, sbp->f_mntfromname, MNAMELEN);
895	}
896	strncpy(sbp->f_fstypename, mp->mnt_vfc->vfc_name, MFSNAMELEN);
897	return (0);
898}
899
900static int
901msdosfs_sync(mp, waitfor, cred, p)
902	struct mount *mp;
903	int waitfor;
904	struct ucred *cred;
905	struct proc *p;
906{
907	struct vnode *vp, *nvp;
908	struct denode *dep;
909	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
910	int error, allerror = 0;
911
912	/*
913	 * If we ever switch to not updating all of the fats all the time,
914	 * this would be the place to update them from the first one.
915	 */
916	if (pmp->pm_fmod != 0)
917		if (pmp->pm_flags & MSDOSFSMNT_RONLY)
918			panic("msdosfs_sync: rofs mod");
919		else {
920			/* update fats here */
921		}
922	/*
923	 * Write back each (modified) denode.
924	 */
925	simple_lock(&mntvnode_slock);
926loop:
927	for (vp = mp->mnt_vnodelist.lh_first;
928	     vp != NULL;
929	     vp = nvp) {
930		/*
931		 * If the vnode that we are about to sync is no longer
932		 * assoicated with this mount point, start over.
933		 */
934		if (vp->v_mount != mp)
935			goto loop;
936
937		simple_lock(&vp->v_interlock);
938		nvp = vp->v_mntvnodes.le_next;
939		dep = VTODE(vp);
940		if (vp->v_type == VNON || ((dep->de_flag &
941		    (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0)
942		    && vp->v_dirtyblkhd.lh_first == NULL) {
943			simple_unlock(&vp->v_interlock);
944			continue;
945		}
946		simple_unlock(&mntvnode_slock);
947		error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, p);
948		if (error) {
949			simple_lock(&mntvnode_slock);
950			if (error == ENOENT)
951				goto loop;
952			continue;
953		}
954		error = VOP_FSYNC(vp, cred, waitfor, p);
955		if (error)
956			allerror = error;
957		VOP_UNLOCK(vp, 0, p);
958		vrele(vp);	/* done with this one	 */
959		simple_lock(&mntvnode_slock);
960	}
961	simple_unlock(&mntvnode_slock);
962
963	/*
964	 * Flush filesystem control info.
965	 */
966	error = VOP_FSYNC(pmp->pm_devvp, cred, waitfor, p);
967	if (error)
968		allerror = error;
969	return (allerror);
970}
971
972static int
973msdosfs_fhtovp(mp, fhp, nam, vpp, exflagsp, credanonp)
974	struct mount *mp;
975	struct fid *fhp;
976	struct sockaddr *nam;
977	struct vnode **vpp;
978	int *exflagsp;
979	struct ucred **credanonp;
980{
981	struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
982	struct defid *defhp = (struct defid *) fhp;
983	struct denode *dep;
984	struct netcred *np;
985	int error;
986
987	np = vfs_export_lookup(mp, &pmp->pm_export, nam);
988	if (np == NULL)
989		return (EACCES);
990	error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep);
991	if (error) {
992		*vpp = NULLVP;
993		return (error);
994	}
995	*vpp = DETOV(dep);
996	*exflagsp = np->netc_exflags;
997	*credanonp = &np->netc_anon;
998	return (0);
999}
1000
1001static int
1002msdosfs_vptofh(vp, fhp)
1003	struct vnode *vp;
1004	struct fid *fhp;
1005{
1006	struct denode *dep;
1007	struct defid *defhp;
1008
1009	dep = VTODE(vp);
1010	defhp = (struct defid *)fhp;
1011	defhp->defid_len = sizeof(struct defid);
1012	defhp->defid_dirclust = dep->de_dirclust;
1013	defhp->defid_dirofs = dep->de_diroffset;
1014	/* defhp->defid_gen = dep->de_gen; */
1015	return (0);
1016}
1017
1018static int
1019msdosfs_vget(mp, ino, vpp)
1020	struct mount *mp;
1021	ino_t ino;
1022	struct vnode **vpp;
1023{
1024	return EOPNOTSUPP;
1025}
1026
1027static struct vfsops msdosfs_vfsops = {
1028	msdosfs_mount,
1029	msdosfs_start,
1030	msdosfs_unmount,
1031	msdosfs_root,
1032	msdosfs_quotactl,
1033	msdosfs_statfs,
1034	msdosfs_sync,
1035	msdosfs_vget,
1036	msdosfs_fhtovp,
1037	msdosfs_vptofh,
1038	msdosfs_init
1039};
1040
1041VFS_SET(msdosfs_vfsops, msdos, MOUNT_MSDOS, 0);
1042