1 /* $FreeBSD$ */
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/buf.h>
54 #include <sys/conf.h>
55 #include <sys/fcntl.h>
56 #include <sys/iconv.h>
57 #include <sys/kernel.h>
58 #include <sys/lock.h>
59 #include <sys/malloc.h>
60 #include <sys/mount.h>
61 #include <sys/mutex.h>
62 #include <sys/namei.h>
63 #include <sys/priv.h>
64 #include <sys/proc.h>
65 #include <sys/stat.h>
66 #include <sys/vnode.h>
67
68 #include <geom/geom.h>
69 #include <geom/geom_vfs.h>
70
71 #include <fs/msdosfs/bootsect.h>
72 #include <fs/msdosfs/bpb.h>
73 #include <fs/msdosfs/direntry.h>
74 #include <fs/msdosfs/denode.h>
75 #include <fs/msdosfs/fat.h>
76 #include <fs/msdosfs/msdosfsmount.h>
77
78 static const char msdosfs_lock_msg[] = "fatlk";
79
80 /* Mount options that we support. */
81 static const char *msdosfs_opts[] = {
82 "async", "noatime", "noclusterr", "noclusterw",
83 "export", "force", "from", "sync",
84 "cs_dos", "cs_local", "cs_win", "dirmask",
85 "gid", "kiconv", "large", "longname",
86 "longnames", "mask", "shortname", "shortnames",
87 "uid", "win95", "nowin95",
88 NULL
89 };
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
102 MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure");
103 static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table");
104
105 struct iconv_functions *msdosfs_iconv;
106
107 static int update_mp(struct mount *mp, struct thread *td);
108 static int mountmsdosfs(struct vnode *devvp, struct mount *mp);
109 static vfs_fhtovp_t msdosfs_fhtovp;
110 static vfs_mount_t msdosfs_mount;
111 static vfs_root_t msdosfs_root;
112 static vfs_statfs_t msdosfs_statfs;
113 static vfs_sync_t msdosfs_sync;
114 static vfs_unmount_t msdosfs_unmount;
115
116 /* Maximum length of a character set name (arbitrary). */
117 #define MAXCSLEN 64
118
119 static int
120 update_mp(struct mount *mp, struct thread *td)
121 {
122 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
123 void *dos, *win, *local;
124 int error, v;
125
126 if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) {
127 if (msdosfs_iconv != NULL) {
128 error = vfs_getopt(mp->mnt_optnew,
129 "cs_win", &win, NULL);
130 if (!error)
131 error = vfs_getopt(mp->mnt_optnew,
132 "cs_local", &local, NULL);
133 if (!error)
134 error = vfs_getopt(mp->mnt_optnew,
135 "cs_dos", &dos, NULL);
136 if (!error) {
137 msdosfs_iconv->open(win, local, &pmp->pm_u2w);
138 msdosfs_iconv->open(local, win, &pmp->pm_w2u);
139 msdosfs_iconv->open(dos, local, &pmp->pm_u2d);
140 msdosfs_iconv->open(local, dos, &pmp->pm_d2u);
141 }
142 if (error != 0)
143 return (error);
144 } else {
145 pmp->pm_w2u = NULL;
146 pmp->pm_u2w = NULL;
147 pmp->pm_d2u = NULL;
148 pmp->pm_u2d = NULL;
149 }
150 }
151
152 if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1)
153 pmp->pm_gid = v;
154 if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1)
155 pmp->pm_uid = v;
156 if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1)
157 pmp->pm_mask = v & ALLPERMS;
158 if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1)
159 pmp->pm_dirmask = v & ALLPERMS;
160 vfs_flagopt(mp->mnt_optnew, "shortname",
161 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME);
162 vfs_flagopt(mp->mnt_optnew, "shortnames",
163 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME);
164 vfs_flagopt(mp->mnt_optnew, "longname",
165 &pmp->pm_flags, MSDOSFSMNT_LONGNAME);
166 vfs_flagopt(mp->mnt_optnew, "longnames",
167 &pmp->pm_flags, MSDOSFSMNT_LONGNAME);
168 vfs_flagopt(mp->mnt_optnew, "kiconv",
169 &pmp->pm_flags, MSDOSFSMNT_KICONV);
170
171 if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0)
172 pmp->pm_flags |= MSDOSFSMNT_NOWIN95;
173 else
174 pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95;
175
176 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95)
177 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME;
178 else
179 pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
180 return 0;
181 }
182
183 static int
184 msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags)
185 {
186 struct msdosfs_args args;
187 struct export_args exp;
188 int error;
189
190 if (data == NULL)
191 return (EINVAL);
192 error = copyin(data, &args, sizeof args);
193 if (error)
194 return (error);
195 vfs_oexport_conv(&args.export, &exp);
196
197 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN);
198 ma = mount_arg(ma, "export", &exp, sizeof(exp));
199 ma = mount_argf(ma, "uid", "%d", args.uid);
200 ma = mount_argf(ma, "gid", "%d", args.gid);
201 ma = mount_argf(ma, "mask", "%d", args.mask);
202 ma = mount_argf(ma, "dirmask", "%d", args.dirmask);
203
204 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname");
205 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname");
206 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95");
207 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv");
208
209 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN);
210 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN);
211 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN);
212
213 error = kernel_mount(ma, flags);
214
215 return (error);
216 }
217
218 /*
219 * mp - path - addr in user space of mount point (ie /usr or whatever)
220 * data - addr in user space of mount params including the name of the block
221 * special file to treat as a filesystem.
222 */
223 static int
224 msdosfs_mount(struct mount *mp)
225 {
226 struct vnode *devvp; /* vnode for blk device to mount */
227 struct thread *td;
228 /* msdosfs specific mount control block */
229 struct msdosfsmount *pmp = NULL;
230 struct nameidata ndp;
231 int error, flags;
232 accmode_t accmode;
233 char *from;
234
235 td = curthread;
236 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts))
237 return (EINVAL);
238
239 /*
240 * If updating, check whether changing from read-only to
241 * read/write; if there is no device name, that's all we do.
242 */
243 if (mp->mnt_flag & MNT_UPDATE) {
244 pmp = VFSTOMSDOSFS(mp);
245 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) {
246 /*
247 * Forbid export requests if filesystem has
248 * MSDOSFS_LARGEFS flag set.
249 */
250 if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) {
251 vfs_mount_error(mp,
252 "MSDOSFS_LARGEFS flag set, cannot export");
253 return (EOPNOTSUPP);
254 }
255 }
256 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) &&
257 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
258 error = VFS_SYNC(mp, MNT_WAIT);
259 if (error)
260 return (error);
261 flags = WRITECLOSE;
262 if (mp->mnt_flag & MNT_FORCE)
263 flags |= FORCECLOSE;
264 error = vflush(mp, 0, flags, td);
265 if (error)
266 return (error);
267
268 /*
269 * Now the volume is clean. Mark it so while the
270 * device is still rw.
271 */
272 error = markvoldirty(pmp, 0);
273 if (error) {
274 (void)markvoldirty(pmp, 1);
275 return (error);
276 }
277
278 /* Downgrade the device from rw to ro. */
279 g_topology_lock();
280 error = g_access(pmp->pm_cp, 0, -1, 0);
281 g_topology_unlock();
282 if (error) {
283 (void)markvoldirty(pmp, 1);
284 return (error);
285 }
286
287 /*
288 * Backing out after an error was painful in the
289 * above. Now we are committed to succeeding.
290 */
291 pmp->pm_fmod = 0;
292 pmp->pm_flags |= MSDOSFSMNT_RONLY;
293 MNT_ILOCK(mp);
294 mp->mnt_flag |= MNT_RDONLY;
295 MNT_IUNLOCK(mp);
296 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) &&
297 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
298 /*
299 * If upgrade to read-write by non-root, then verify
300 * that user has necessary permissions on the device.
301 */
302 devvp = pmp->pm_devvp;
303 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
304 error = VOP_ACCESS(devvp, VREAD | VWRITE,
305 td->td_ucred, td);
306 if (error)
307 error = priv_check(td, PRIV_VFS_MOUNT_PERM);
308 if (error) {
309 VOP_UNLOCK(devvp, 0);
310 return (error);
311 }
312 VOP_UNLOCK(devvp, 0);
313 g_topology_lock();
314 error = g_access(pmp->pm_cp, 0, 1, 0);
315 g_topology_unlock();
316 if (error)
317 return (error);
318
319 pmp->pm_fmod = 1;
320 pmp->pm_flags &= ~MSDOSFSMNT_RONLY;
321 MNT_ILOCK(mp);
322 mp->mnt_flag &= ~MNT_RDONLY;
323 MNT_IUNLOCK(mp);
324
325 /* Now that the volume is modifiable, mark it dirty. */
326 error = markvoldirty(pmp, 1);
327 if (error)
328 return (error);
329 }
330 }
331 /*
332 * Not an update, or updating the name: look up the name
333 * and verify that it refers to a sensible disk device.
334 */
335 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL))
336 return (EINVAL);
337 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td);
338 error = namei(&ndp);
339 if (error)
340 return (error);
341 devvp = ndp.ni_vp;
342 NDFREE(&ndp, NDF_ONLY_PNBUF);
343
344 if (!vn_isdisk(devvp, &error)) {
345 vput(devvp);
346 return (error);
347 }
348 /*
349 * If mount by non-root, then verify that user has necessary
350 * permissions on the device.
351 */
352 accmode = VREAD;
353 if ((mp->mnt_flag & MNT_RDONLY) == 0)
354 accmode |= VWRITE;
355 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td);
356 if (error)
357 error = priv_check(td, PRIV_VFS_MOUNT_PERM);
358 if (error) {
359 vput(devvp);
360 return (error);
361 }
362 if ((mp->mnt_flag & MNT_UPDATE) == 0) {
363 error = mountmsdosfs(devvp, mp);
364 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */
365 pmp = VFSTOMSDOSFS(mp);
366 #endif
367 } else {
368 vput(devvp);
369 if (devvp != pmp->pm_devvp)
370 return (EINVAL); /* XXX needs translation */
371 }
372 if (error) {
373 vrele(devvp);
374 return (error);
375 }
376
377 error = update_mp(mp, td);
378 if (error) {
379 if ((mp->mnt_flag & MNT_UPDATE) == 0)
380 msdosfs_unmount(mp, MNT_FORCE);
381 return error;
382 }
383
384 vfs_mountedfrom(mp, from);
385 #ifdef MSDOSFS_DEBUG
386 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap);
387 #endif
388 return (0);
389 }
390
391 static int
392 mountmsdosfs(struct vnode *devvp, struct mount *mp)
393 {
394 struct msdosfsmount *pmp;
395 struct buf *bp;
396 struct cdev *dev;
397 union bootsector *bsp;
398 struct byte_bpb33 *b33;
399 struct byte_bpb50 *b50;
400 struct byte_bpb710 *b710;
401 u_int8_t SecPerClust;
402 u_long clusters;
403 int ronly, error;
404 struct g_consumer *cp;
405 struct bufobj *bo;
406
407 bp = NULL; /* This and pmp both used in error_exit. */
408 pmp = NULL;
409 ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
410
411 dev = devvp->v_rdev;
412 if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0,
413 (uintptr_t)mp) == 0) {
414 VOP_UNLOCK(devvp, 0);
415 return (EBUSY);
416 }
417 g_topology_lock();
418 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1);
419 g_topology_unlock();
420 if (error != 0) {
421 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0);
422 VOP_UNLOCK(devvp, 0);
423 return (error);
424 }
425 dev_ref(dev);
426 VOP_UNLOCK(devvp, 0);
427
428 bo = &devvp->v_bufobj;
429
430 /*
431 * Read the boot sector of the filesystem, and then check the
432 * boot signature. If not a dos boot sector then error out.
433 *
434 * NOTE: 8192 is a magic size that works for ffs.
435 */
436 error = bread(devvp, 0, 8192, NOCRED, &bp);
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.bsBPB;
444
445 #ifndef MSDOSFS_NOCHECKSIG
446 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
447 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
448 error = EINVAL;
449 goto error_exit;
450 }
451 #endif
452
453 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO);
454 pmp->pm_mountp = mp;
455 pmp->pm_cp = cp;
456 pmp->pm_bo = bo;
457
458 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0);
459
460 /*
461 * Initialize ownerships and permissions, since nothing else will
462 * initialize them iff we are mounting root.
463 */
464 pmp->pm_uid = UID_ROOT;
465 pmp->pm_gid = GID_WHEEL;
466 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH |
467 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR;
468
469 /*
470 * Experimental support for large MS-DOS filesystems.
471 * WARNING: This uses at least 32 bytes of kernel memory (which is not
472 * reclaimed until the FS is unmounted) for each file on disk to map
473 * between the 32-bit inode numbers used by VFS and the 64-bit
474 * pseudo-inode numbers used internally by msdosfs. This is only
475 * safe to use in certain controlled situations (e.g. read-only FS
476 * with less than 1 million files).
477 * Since the mappings do not persist across unmounts (or reboots), these
478 * filesystems are not suitable for exporting through NFS, or any other
479 * application that requires fixed inode numbers.
480 */
481 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS);
482
483 /*
484 * Compute several useful quantities from the bpb in the
485 * bootsector. Copy in the dos 5 variant of the bpb then fix up
486 * the fields that are different between dos 5 and dos 3.3.
487 */
488 SecPerClust = b50->bpbSecPerClust;
489 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
490 if (pmp->pm_BytesPerSec < DEV_BSIZE) {
491 error = EINVAL;
492 goto error_exit;
493 }
494 pmp->pm_ResSectors = getushort(b50->bpbResSectors);
495 pmp->pm_FATs = b50->bpbFATs;
496 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
497 pmp->pm_Sectors = getushort(b50->bpbSectors);
498 pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
499 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
500 pmp->pm_Heads = getushort(b50->bpbHeads);
501 pmp->pm_Media = b50->bpbMedia;
502
503 /* calculate the ratio of sector size to DEV_BSIZE */
504 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE;
505
506 /*
507 * We don't check pm_Heads nor pm_SecPerTrack, because
508 * these may not be set for EFI file systems. We don't
509 * use these anyway, so we're unaffected if they are
510 * invalid.
511 */
512 if (!pmp->pm_BytesPerSec || !SecPerClust) {
513 error = EINVAL;
514 goto error_exit;
515 }
516
517 if (pmp->pm_Sectors == 0) {
518 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
519 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
520 } else {
521 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
522 pmp->pm_HugeSectors = pmp->pm_Sectors;
523 }
524 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) {
525 if (pmp->pm_HugeSectors > 0xffffffff /
526 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) {
527 /*
528 * We cannot deal currently with this size of disk
529 * due to fileid limitations (see msdosfs_getattr and
530 * msdosfs_readdir)
531 */
532 error = EINVAL;
533 vfs_mount_error(mp,
534 "Disk too big, try '-o large' mount option");
535 goto error_exit;
536 }
537 }
538
539 if (pmp->pm_RootDirEnts == 0) {
540 if (pmp->pm_FATsecs
541 || getushort(b710->bpbFSVers)) {
542 error = EINVAL;
543 #ifdef MSDOSFS_DEBUG
544 printf("mountmsdosfs(): bad FAT32 filesystem\n");
545 #endif
546 goto error_exit;
547 }
548 pmp->pm_fatmask = FAT32_MASK;
549 pmp->pm_fatmult = 4;
550 pmp->pm_fatdiv = 1;
551 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
552 if (getushort(b710->bpbExtFlags) & FATMIRROR)
553 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
554 else
555 pmp->pm_flags |= MSDOSFS_FATMIRROR;
556 } else
557 pmp->pm_flags |= MSDOSFS_FATMIRROR;
558
559 /*
560 * Check a few values (could do some more):
561 * - logical sector size: power of 2, >= block size
562 * - sectors per cluster: power of 2, >= 1
563 * - number of sectors: >= 1, <= size of partition
564 * - number of FAT sectors: >= 1
565 */
566 if ( (SecPerClust == 0)
567 || (SecPerClust & (SecPerClust - 1))
568 || (pmp->pm_BytesPerSec < DEV_BSIZE)
569 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
570 || (pmp->pm_HugeSectors == 0)
571 || (pmp->pm_FATsecs == 0)
572 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE)
573 ) {
574 error = EINVAL;
575 goto error_exit;
576 }
577
578 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec;
579 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */
580 pmp->pm_FATsecs *= pmp->pm_BlkPerSec;
581 SecPerClust *= pmp->pm_BlkPerSec;
582
583 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec;
584
585 if (FAT32(pmp)) {
586 pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
587 pmp->pm_firstcluster = pmp->pm_fatblk
588 + (pmp->pm_FATs * pmp->pm_FATsecs);
589 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec;
590 } else {
591 pmp->pm_rootdirblk = pmp->pm_fatblk +
592 (pmp->pm_FATs * pmp->pm_FATsecs);
593 pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts *
594 sizeof(struct direntry), DEV_BSIZE); /* in blocks */
595 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
596 }
597
598 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
599 SecPerClust + 1;
600 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */
601
602 if (pmp->pm_fatmask == 0) {
603 if (pmp->pm_maxcluster
604 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
605 /*
606 * This will usually be a floppy disk. This size makes
607 * sure that one fat entry will not be split across
608 * multiple blocks.
609 */
610 pmp->pm_fatmask = FAT12_MASK;
611 pmp->pm_fatmult = 3;
612 pmp->pm_fatdiv = 2;
613 } else {
614 pmp->pm_fatmask = FAT16_MASK;
615 pmp->pm_fatmult = 2;
616 pmp->pm_fatdiv = 1;
617 }
618 }
619
620 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv;
621 if (pmp->pm_maxcluster >= clusters) {
622 #ifdef MSDOSFS_DEBUG
623 printf("Warning: number of clusters (%ld) exceeds FAT "
624 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters);
625 #endif
626 pmp->pm_maxcluster = clusters - 1;
627 }
628
629 if (FAT12(pmp))
630 pmp->pm_fatblocksize = 3 * 512;
631 else
632 pmp->pm_fatblocksize = PAGE_SIZE;
633 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize,
634 pmp->pm_BytesPerSec);
635 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE;
636 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1;
637
638 /*
639 * Compute mask and shift value for isolating cluster relative byte
640 * offsets and cluster numbers from a file offset.
641 */
642 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE;
643 pmp->pm_crbomask = pmp->pm_bpcluster - 1;
644 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
645
646 /*
647 * Check for valid cluster size
648 * must be a power of 2
649 */
650 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
651 error = EINVAL;
652 goto error_exit;
653 }
654
655 /*
656 * Release the bootsector buffer.
657 */
658 brelse(bp);
659 bp = NULL;
660
661 /*
662 * Check the fsinfo sector if we have one. Silently fix up our
663 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff)
664 * or too large. Ignore fp->fsinfree for now, since we need to
665 * read the entire FAT anyway to fill the inuse map.
666 */
667 if (pmp->pm_fsinfo) {
668 struct fsinfo *fp;
669
670 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec,
671 NOCRED, &bp)) != 0)
672 goto error_exit;
673 fp = (struct fsinfo *)bp->b_data;
674 if (!bcmp(fp->fsisig1, "RRaA", 4)
675 && !bcmp(fp->fsisig2, "rrAa", 4)
676 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) {
677 pmp->pm_nxtfree = getulong(fp->fsinxtfree);
678 if (pmp->pm_nxtfree > pmp->pm_maxcluster)
679 pmp->pm_nxtfree = CLUST_FIRST;
680 } else
681 pmp->pm_fsinfo = 0;
682 brelse(bp);
683 bp = NULL;
684 }
685
686 /*
687 * Finish initializing pmp->pm_nxtfree (just in case the first few
688 * sectors aren't properly reserved in the FAT). This completes
689 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized
690 * value if there is no fsinfo. We will use pmp->pm_nxtfree
691 * internally even if there is no fsinfo.
692 */
693 if (pmp->pm_nxtfree < CLUST_FIRST)
694 pmp->pm_nxtfree = CLUST_FIRST;
695
696 /*
697 * Allocate memory for the bitmap of allocated clusters, and then
698 * fill it in.
699 */
700 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS)
701 * sizeof(*pmp->pm_inusemap),
702 M_MSDOSFSFAT, M_WAITOK);
703
704 /*
705 * fillinusemap() needs pm_devvp.
706 */
707 pmp->pm_devvp = devvp;
708 pmp->pm_dev = dev;
709
710 /*
711 * Have the inuse map filled in.
712 */
713 MSDOSFS_LOCK_MP(pmp);
714 error = fillinusemap(pmp);
715 MSDOSFS_UNLOCK_MP(pmp);
716 if (error != 0)
717 goto error_exit;
718
719 /*
720 * If they want fat updates to be synchronous then let them suffer
721 * the performance degradation in exchange for the on disk copy of
722 * the fat being correct just about all the time. I suppose this
723 * would be a good thing to turn on if the kernel is still flakey.
724 */
725 if (mp->mnt_flag & MNT_SYNCHRONOUS)
726 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
727
728 /*
729 * Finish up.
730 */
731 if (ronly)
732 pmp->pm_flags |= MSDOSFSMNT_RONLY;
733 else {
734 if ((error = markvoldirty(pmp, 1)) != 0) {
735 (void)markvoldirty(pmp, 0);
736 goto error_exit;
737 }
738 pmp->pm_fmod = 1;
739 }
740 mp->mnt_data = pmp;
741 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
742 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
743 MNT_ILOCK(mp);
744 mp->mnt_flag |= MNT_LOCAL;
745 mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF;
746 MNT_IUNLOCK(mp);
747
748 if (pmp->pm_flags & MSDOSFS_LARGEFS)
749 msdosfs_fileno_init(mp);
750
751 return 0;
752
753 error_exit:
754 if (bp)
755 brelse(bp);
756 if (cp != NULL) {
757 g_topology_lock();
758 g_vfs_close(cp);
759 g_topology_unlock();
760 }
761 if (pmp) {
762 lockdestroy(&pmp->pm_fatlock);
763 free(pmp->pm_inusemap, M_MSDOSFSFAT);
764 free(pmp, M_MSDOSFSMNT);
765 mp->mnt_data = NULL;
766 }
767 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0);
768 dev_rel(dev);
769 return (error);
770 }
771
772 /*
773 * Unmount the filesystem described by mp.
774 */
775 static int
776 msdosfs_unmount(struct mount *mp, int mntflags)
777 {
778 struct msdosfsmount *pmp;
779 int error, flags;
780
781 error = flags = 0;
782 pmp = VFSTOMSDOSFS(mp);
783 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0)
784 error = msdosfs_sync(mp, MNT_WAIT);
785 if ((mntflags & MNT_FORCE) != 0)
786 flags |= FORCECLOSE;
787 else if (error != 0)
788 return (error);
789 error = vflush(mp, 0, flags, curthread);
790 if (error != 0 && error != ENXIO)
791 return (error);
792 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) {
793 error = markvoldirty(pmp, 0);
794 if (error && error != ENXIO) {
795 (void)markvoldirty(pmp, 1);
796 return (error);
797 }
798 }
799 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) {
800 if (pmp->pm_w2u)
801 msdosfs_iconv->close(pmp->pm_w2u);
802 if (pmp->pm_u2w)
803 msdosfs_iconv->close(pmp->pm_u2w);
804 if (pmp->pm_d2u)
805 msdosfs_iconv->close(pmp->pm_d2u);
806 if (pmp->pm_u2d)
807 msdosfs_iconv->close(pmp->pm_u2d);
808 }
809
810 #ifdef MSDOSFS_DEBUG
811 {
812 struct vnode *vp = pmp->pm_devvp;
813 struct bufobj *bo;
814
815 bo = &vp->v_bufobj;
816 BO_LOCK(bo);
817 VI_LOCK(vp);
818 vn_printf(vp,
819 "msdosfs_umount(): just before calling VOP_CLOSE()\n");
820 printf("freef %p, freeb %p, mount %p\n",
821 TAILQ_NEXT(vp, v_actfreelist), vp->v_actfreelist.tqe_prev,
822 vp->v_mount);
823 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n",
824 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd),
825 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd),
826 vp->v_bufobj.bo_numoutput, vp->v_type);
827 VI_UNLOCK(vp);
828 BO_UNLOCK(bo);
829 }
830 #endif
831 g_topology_lock();
832 g_vfs_close(pmp->pm_cp);
833 g_topology_unlock();
834 atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0);
835 vrele(pmp->pm_devvp);
836 dev_rel(pmp->pm_dev);
837 free(pmp->pm_inusemap, M_MSDOSFSFAT);
838 if (pmp->pm_flags & MSDOSFS_LARGEFS)
839 msdosfs_fileno_free(mp);
840 lockdestroy(&pmp->pm_fatlock);
841 free(pmp, M_MSDOSFSMNT);
842 mp->mnt_data = NULL;
843 MNT_ILOCK(mp);
844 mp->mnt_flag &= ~MNT_LOCAL;
845 MNT_IUNLOCK(mp);
846 return (error);
847 }
848
849 static int
850 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp)
851 {
852 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
853 struct denode *ndep;
854 int error;
855
856 #ifdef MSDOSFS_DEBUG
857 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp);
858 #endif
859 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep);
860 if (error)
861 return (error);
862 *vpp = DETOV(ndep);
863 return (0);
864 }
865
866 static int
867 msdosfs_statfs(struct mount *mp, struct statfs *sbp)
868 {
869 struct msdosfsmount *pmp;
870
871 pmp = VFSTOMSDOSFS(mp);
872 sbp->f_bsize = pmp->pm_bpcluster;
873 sbp->f_iosize = pmp->pm_bpcluster;
874 sbp->f_blocks = pmp->pm_maxcluster + 1;
875 sbp->f_bfree = pmp->pm_freeclustercount;
876 sbp->f_bavail = pmp->pm_freeclustercount;
877 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */
878 sbp->f_ffree = 0; /* what to put in here? */
879 return (0);
880 }
881
882 /*
883 * If we have an FSInfo block, update it.
884 */
885 static int
886 msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor)
887 {
888 struct fsinfo *fp;
889 struct buf *bp;
890 int error;
891
892 MSDOSFS_LOCK_MP(pmp);
893 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) {
894 error = 0;
895 goto unlock;
896 }
897 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec,
898 NOCRED, &bp);
899 if (error != 0) {
900 brelse(bp);
901 goto unlock;
902 }
903 fp = (struct fsinfo *)bp->b_data;
904 putulong(fp->fsinfree, pmp->pm_freeclustercount);
905 putulong(fp->fsinxtfree, pmp->pm_nxtfree);
906 pmp->pm_flags &= ~MSDOSFS_FSIMOD;
907 if (waitfor == MNT_WAIT)
908 error = bwrite(bp);
909 else
910 bawrite(bp);
911 unlock:
912 MSDOSFS_UNLOCK_MP(pmp);
913 return (error);
914 }
915
916 static int
917 msdosfs_sync(struct mount *mp, int waitfor)
918 {
919 struct vnode *vp, *nvp;
920 struct thread *td;
921 struct denode *dep;
922 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
923 int error, allerror = 0;
924
925 td = curthread;
926
927 /*
928 * If we ever switch to not updating all of the fats all the time,
929 * this would be the place to update them from the first one.
930 */
931 if (pmp->pm_fmod != 0) {
932 if (pmp->pm_flags & MSDOSFSMNT_RONLY)
933 panic("msdosfs_sync: rofs mod");
934 else {
935 /* update fats here */
936 }
937 }
938 /*
939 * Write back each (modified) denode.
940 */
941 loop:
942 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) {
943 if (vp->v_type == VNON) {
944 VI_UNLOCK(vp);
945 continue;
946 }
947 dep = VTODE(vp);
948 if ((dep->de_flag &
949 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 &&
950 (vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
951 waitfor == MNT_LAZY)) {
952 VI_UNLOCK(vp);
953 continue;
954 }
955 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
956 if (error) {
957 if (error == ENOENT)
958 goto loop;
959 continue;
960 }
961 error = VOP_FSYNC(vp, waitfor, td);
962 if (error)
963 allerror = error;
964 VOP_UNLOCK(vp, 0);
965 vrele(vp);
966 }
967
968 /*
969 * Flush filesystem control info.
970 */
971 if (waitfor != MNT_LAZY) {
972 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY);
973 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td);
974 if (error)
975 allerror = error;
976 VOP_UNLOCK(pmp->pm_devvp, 0);
977 }
978
979 error = msdosfs_fsiflush(pmp, waitfor);
980 if (error != 0)
981 allerror = error;
982 return (allerror);
983 }
984
985 static int
986 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
987 {
988 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
989 struct defid *defhp = (struct defid *) fhp;
990 struct denode *dep;
991 int error;
992
993 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep);
994 if (error) {
995 *vpp = NULLVP;
996 return (error);
997 }
998 *vpp = DETOV(dep);
999 vnode_create_vobject(*vpp, dep->de_FileSize, curthread);
1000 return (0);
1001 }
1002
1003 static struct vfsops msdosfs_vfsops = {
1004 .vfs_fhtovp = msdosfs_fhtovp,
1005 .vfs_mount = msdosfs_mount,
1006 .vfs_cmount = msdosfs_cmount,
1007 .vfs_root = msdosfs_root,
1008 .vfs_statfs = msdosfs_statfs,
1009 .vfs_sync = msdosfs_sync,
1010 .vfs_unmount = msdosfs_unmount,
1011 };
1012
1013 VFS_SET(msdosfs_vfsops, msdosfs, 0);
1014 MODULE_VERSION(msdosfs, 1);
Cache object: ffc82967498fb4f5bd4a0dfc734a36cb
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