1 /* $FreeBSD: releng/10.0/sys/fs/msdosfs/msdosfs_vfsops.c 246921 2013-02-17 20:35:54Z kib $ */
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 if (!(pmp->pm_flags &
179 (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) {
180 struct vnode *rootvp;
181
182 /*
183 * Try to divine whether to support Win'95 long filenames
184 */
185 if (FAT32(pmp))
186 pmp->pm_flags |= MSDOSFSMNT_LONGNAME;
187 else {
188 if ((error =
189 msdosfs_root(mp, LK_EXCLUSIVE, &rootvp)) != 0)
190 return error;
191 pmp->pm_flags |= findwin95(VTODE(rootvp)) ?
192 MSDOSFSMNT_LONGNAME : MSDOSFSMNT_SHORTNAME;
193 vput(rootvp);
194 }
195 }
196 return 0;
197 }
198
199 static int
200 msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags)
201 {
202 struct msdosfs_args args;
203 struct export_args exp;
204 int error;
205
206 if (data == NULL)
207 return (EINVAL);
208 error = copyin(data, &args, sizeof args);
209 if (error)
210 return (error);
211 vfs_oexport_conv(&args.export, &exp);
212
213 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN);
214 ma = mount_arg(ma, "export", &exp, sizeof(exp));
215 ma = mount_argf(ma, "uid", "%d", args.uid);
216 ma = mount_argf(ma, "gid", "%d", args.gid);
217 ma = mount_argf(ma, "mask", "%d", args.mask);
218 ma = mount_argf(ma, "dirmask", "%d", args.dirmask);
219
220 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname");
221 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname");
222 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95");
223 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv");
224
225 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN);
226 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN);
227 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN);
228
229 error = kernel_mount(ma, flags);
230
231 return (error);
232 }
233
234 /*
235 * mp - path - addr in user space of mount point (ie /usr or whatever)
236 * data - addr in user space of mount params including the name of the block
237 * special file to treat as a filesystem.
238 */
239 static int
240 msdosfs_mount(struct mount *mp)
241 {
242 struct vnode *devvp; /* vnode for blk device to mount */
243 struct thread *td;
244 /* msdosfs specific mount control block */
245 struct msdosfsmount *pmp = NULL;
246 struct nameidata ndp;
247 int error, flags;
248 accmode_t accmode;
249 char *from;
250
251 td = curthread;
252 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts))
253 return (EINVAL);
254
255 /*
256 * If updating, check whether changing from read-only to
257 * read/write; if there is no device name, that's all we do.
258 */
259 if (mp->mnt_flag & MNT_UPDATE) {
260 pmp = VFSTOMSDOSFS(mp);
261 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) {
262 /*
263 * Forbid export requests if filesystem has
264 * MSDOSFS_LARGEFS flag set.
265 */
266 if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) {
267 vfs_mount_error(mp,
268 "MSDOSFS_LARGEFS flag set, cannot export");
269 return (EOPNOTSUPP);
270 }
271 }
272 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) &&
273 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
274 error = VFS_SYNC(mp, MNT_WAIT);
275 if (error)
276 return (error);
277 flags = WRITECLOSE;
278 if (mp->mnt_flag & MNT_FORCE)
279 flags |= FORCECLOSE;
280 error = vflush(mp, 0, flags, td);
281 if (error)
282 return (error);
283
284 /*
285 * Now the volume is clean. Mark it so while the
286 * device is still rw.
287 */
288 error = markvoldirty(pmp, 0);
289 if (error) {
290 (void)markvoldirty(pmp, 1);
291 return (error);
292 }
293
294 /* Downgrade the device from rw to ro. */
295 DROP_GIANT();
296 g_topology_lock();
297 error = g_access(pmp->pm_cp, 0, -1, 0);
298 g_topology_unlock();
299 PICKUP_GIANT();
300 if (error) {
301 (void)markvoldirty(pmp, 1);
302 return (error);
303 }
304
305 /*
306 * Backing out after an error was painful in the
307 * above. Now we are committed to succeeding.
308 */
309 pmp->pm_fmod = 0;
310 pmp->pm_flags |= MSDOSFSMNT_RONLY;
311 MNT_ILOCK(mp);
312 mp->mnt_flag |= MNT_RDONLY;
313 MNT_IUNLOCK(mp);
314 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) &&
315 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) {
316 /*
317 * If upgrade to read-write by non-root, then verify
318 * that user has necessary permissions on the device.
319 */
320 devvp = pmp->pm_devvp;
321 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY);
322 error = VOP_ACCESS(devvp, VREAD | VWRITE,
323 td->td_ucred, td);
324 if (error)
325 error = priv_check(td, PRIV_VFS_MOUNT_PERM);
326 if (error) {
327 VOP_UNLOCK(devvp, 0);
328 return (error);
329 }
330 VOP_UNLOCK(devvp, 0);
331 DROP_GIANT();
332 g_topology_lock();
333 error = g_access(pmp->pm_cp, 0, 1, 0);
334 g_topology_unlock();
335 PICKUP_GIANT();
336 if (error)
337 return (error);
338
339 pmp->pm_fmod = 1;
340 pmp->pm_flags &= ~MSDOSFSMNT_RONLY;
341 MNT_ILOCK(mp);
342 mp->mnt_flag &= ~MNT_RDONLY;
343 MNT_IUNLOCK(mp);
344
345 /* Now that the volume is modifiable, mark it dirty. */
346 error = markvoldirty(pmp, 1);
347 if (error)
348 return (error);
349 }
350 }
351 /*
352 * Not an update, or updating the name: look up the name
353 * and verify that it refers to a sensible disk device.
354 */
355 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL))
356 return (EINVAL);
357 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td);
358 error = namei(&ndp);
359 if (error)
360 return (error);
361 devvp = ndp.ni_vp;
362 NDFREE(&ndp, NDF_ONLY_PNBUF);
363
364 if (!vn_isdisk(devvp, &error)) {
365 vput(devvp);
366 return (error);
367 }
368 /*
369 * If mount by non-root, then verify that user has necessary
370 * permissions on the device.
371 */
372 accmode = VREAD;
373 if ((mp->mnt_flag & MNT_RDONLY) == 0)
374 accmode |= VWRITE;
375 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td);
376 if (error)
377 error = priv_check(td, PRIV_VFS_MOUNT_PERM);
378 if (error) {
379 vput(devvp);
380 return (error);
381 }
382 if ((mp->mnt_flag & MNT_UPDATE) == 0) {
383 error = mountmsdosfs(devvp, mp);
384 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */
385 pmp = VFSTOMSDOSFS(mp);
386 #endif
387 } else {
388 vput(devvp);
389 if (devvp != pmp->pm_devvp)
390 return (EINVAL); /* XXX needs translation */
391 }
392 if (error) {
393 vrele(devvp);
394 return (error);
395 }
396
397 error = update_mp(mp, td);
398 if (error) {
399 if ((mp->mnt_flag & MNT_UPDATE) == 0)
400 msdosfs_unmount(mp, MNT_FORCE);
401 return error;
402 }
403
404 if (devvp->v_type == VCHR && devvp->v_rdev != NULL)
405 devvp->v_rdev->si_mountpt = mp;
406 vfs_mountedfrom(mp, from);
407 #ifdef MSDOSFS_DEBUG
408 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap);
409 #endif
410 return (0);
411 }
412
413 static int
414 mountmsdosfs(struct vnode *devvp, struct mount *mp)
415 {
416 struct msdosfsmount *pmp;
417 struct buf *bp;
418 struct cdev *dev;
419 union bootsector *bsp;
420 struct byte_bpb33 *b33;
421 struct byte_bpb50 *b50;
422 struct byte_bpb710 *b710;
423 u_int8_t SecPerClust;
424 u_long clusters;
425 int ronly, error;
426 struct g_consumer *cp;
427 struct bufobj *bo;
428
429 bp = NULL; /* This and pmp both used in error_exit. */
430 pmp = NULL;
431 ronly = (mp->mnt_flag & MNT_RDONLY) != 0;
432
433 dev = devvp->v_rdev;
434 dev_ref(dev);
435 DROP_GIANT();
436 g_topology_lock();
437 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1);
438 g_topology_unlock();
439 PICKUP_GIANT();
440 VOP_UNLOCK(devvp, 0);
441 if (error)
442 goto error_exit;
443
444 bo = &devvp->v_bufobj;
445
446 /*
447 * Read the boot sector of the filesystem, and then check the
448 * boot signature. If not a dos boot sector then error out.
449 *
450 * NOTE: 8192 is a magic size that works for ffs.
451 */
452 error = bread(devvp, 0, 8192, NOCRED, &bp);
453 if (error)
454 goto error_exit;
455 bp->b_flags |= B_AGE;
456 bsp = (union bootsector *)bp->b_data;
457 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB;
458 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB;
459 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB;
460
461 #ifndef MSDOSFS_NOCHECKSIG
462 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0
463 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) {
464 error = EINVAL;
465 goto error_exit;
466 }
467 #endif
468
469 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO);
470 pmp->pm_mountp = mp;
471 pmp->pm_cp = cp;
472 pmp->pm_bo = bo;
473
474 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0);
475
476 /*
477 * Initialize ownerships and permissions, since nothing else will
478 * initialize them iff we are mounting root.
479 */
480 pmp->pm_uid = UID_ROOT;
481 pmp->pm_gid = GID_WHEEL;
482 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH |
483 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR;
484
485 /*
486 * Experimental support for large MS-DOS filesystems.
487 * WARNING: This uses at least 32 bytes of kernel memory (which is not
488 * reclaimed until the FS is unmounted) for each file on disk to map
489 * between the 32-bit inode numbers used by VFS and the 64-bit
490 * pseudo-inode numbers used internally by msdosfs. This is only
491 * safe to use in certain controlled situations (e.g. read-only FS
492 * with less than 1 million files).
493 * Since the mappings do not persist across unmounts (or reboots), these
494 * filesystems are not suitable for exporting through NFS, or any other
495 * application that requires fixed inode numbers.
496 */
497 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS);
498
499 /*
500 * Compute several useful quantities from the bpb in the
501 * bootsector. Copy in the dos 5 variant of the bpb then fix up
502 * the fields that are different between dos 5 and dos 3.3.
503 */
504 SecPerClust = b50->bpbSecPerClust;
505 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec);
506 if (pmp->pm_BytesPerSec < DEV_BSIZE) {
507 error = EINVAL;
508 goto error_exit;
509 }
510 pmp->pm_ResSectors = getushort(b50->bpbResSectors);
511 pmp->pm_FATs = b50->bpbFATs;
512 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts);
513 pmp->pm_Sectors = getushort(b50->bpbSectors);
514 pmp->pm_FATsecs = getushort(b50->bpbFATsecs);
515 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack);
516 pmp->pm_Heads = getushort(b50->bpbHeads);
517 pmp->pm_Media = b50->bpbMedia;
518
519 /* calculate the ratio of sector size to DEV_BSIZE */
520 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE;
521
522 /*
523 * We don't check pm_Heads nor pm_SecPerTrack, because
524 * these may not be set for EFI file systems. We don't
525 * use these anyway, so we're unaffected if they are
526 * invalid.
527 */
528 if (!pmp->pm_BytesPerSec || !SecPerClust) {
529 error = EINVAL;
530 goto error_exit;
531 }
532
533 if (pmp->pm_Sectors == 0) {
534 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs);
535 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors);
536 } else {
537 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs);
538 pmp->pm_HugeSectors = pmp->pm_Sectors;
539 }
540 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) {
541 if (pmp->pm_HugeSectors > 0xffffffff /
542 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) {
543 /*
544 * We cannot deal currently with this size of disk
545 * due to fileid limitations (see msdosfs_getattr and
546 * msdosfs_readdir)
547 */
548 error = EINVAL;
549 vfs_mount_error(mp,
550 "Disk too big, try '-o large' mount option");
551 goto error_exit;
552 }
553 }
554
555 if (pmp->pm_RootDirEnts == 0) {
556 if (pmp->pm_FATsecs
557 || getushort(b710->bpbFSVers)) {
558 error = EINVAL;
559 #ifdef MSDOSFS_DEBUG
560 printf("mountmsdosfs(): bad FAT32 filesystem\n");
561 #endif
562 goto error_exit;
563 }
564 pmp->pm_fatmask = FAT32_MASK;
565 pmp->pm_fatmult = 4;
566 pmp->pm_fatdiv = 1;
567 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs);
568 if (getushort(b710->bpbExtFlags) & FATMIRROR)
569 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM;
570 else
571 pmp->pm_flags |= MSDOSFS_FATMIRROR;
572 } else
573 pmp->pm_flags |= MSDOSFS_FATMIRROR;
574
575 /*
576 * Check a few values (could do some more):
577 * - logical sector size: power of 2, >= block size
578 * - sectors per cluster: power of 2, >= 1
579 * - number of sectors: >= 1, <= size of partition
580 * - number of FAT sectors: >= 1
581 */
582 if ( (SecPerClust == 0)
583 || (SecPerClust & (SecPerClust - 1))
584 || (pmp->pm_BytesPerSec < DEV_BSIZE)
585 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1))
586 || (pmp->pm_HugeSectors == 0)
587 || (pmp->pm_FATsecs == 0)
588 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE)
589 ) {
590 error = EINVAL;
591 goto error_exit;
592 }
593
594 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec;
595 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */
596 pmp->pm_FATsecs *= pmp->pm_BlkPerSec;
597 SecPerClust *= pmp->pm_BlkPerSec;
598
599 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec;
600
601 if (FAT32(pmp)) {
602 pmp->pm_rootdirblk = getulong(b710->bpbRootClust);
603 pmp->pm_firstcluster = pmp->pm_fatblk
604 + (pmp->pm_FATs * pmp->pm_FATsecs);
605 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec;
606 } else {
607 pmp->pm_rootdirblk = pmp->pm_fatblk +
608 (pmp->pm_FATs * pmp->pm_FATsecs);
609 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry)
610 + DEV_BSIZE - 1)
611 / DEV_BSIZE; /* in blocks */
612 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize;
613 }
614
615 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) /
616 SecPerClust + 1;
617 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */
618
619 if (pmp->pm_fatmask == 0) {
620 if (pmp->pm_maxcluster
621 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) {
622 /*
623 * This will usually be a floppy disk. This size makes
624 * sure that one fat entry will not be split across
625 * multiple blocks.
626 */
627 pmp->pm_fatmask = FAT12_MASK;
628 pmp->pm_fatmult = 3;
629 pmp->pm_fatdiv = 2;
630 } else {
631 pmp->pm_fatmask = FAT16_MASK;
632 pmp->pm_fatmult = 2;
633 pmp->pm_fatdiv = 1;
634 }
635 }
636
637 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv;
638 if (pmp->pm_maxcluster >= clusters) {
639 #ifdef MSDOSFS_DEBUG
640 printf("Warning: number of clusters (%ld) exceeds FAT "
641 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters);
642 #endif
643 pmp->pm_maxcluster = clusters - 1;
644 }
645
646 if (FAT12(pmp))
647 pmp->pm_fatblocksize = 3 * 512;
648 else
649 pmp->pm_fatblocksize = PAGE_SIZE;
650 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize,
651 pmp->pm_BytesPerSec);
652 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE;
653 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1;
654
655 /*
656 * Compute mask and shift value for isolating cluster relative byte
657 * offsets and cluster numbers from a file offset.
658 */
659 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE;
660 pmp->pm_crbomask = pmp->pm_bpcluster - 1;
661 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1;
662
663 /*
664 * Check for valid cluster size
665 * must be a power of 2
666 */
667 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) {
668 error = EINVAL;
669 goto error_exit;
670 }
671
672 /*
673 * Release the bootsector buffer.
674 */
675 brelse(bp);
676 bp = NULL;
677
678 /*
679 * Check the fsinfo sector if we have one. Silently fix up our
680 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff)
681 * or too large. Ignore fp->fsinfree for now, since we need to
682 * read the entire FAT anyway to fill the inuse map.
683 */
684 if (pmp->pm_fsinfo) {
685 struct fsinfo *fp;
686
687 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec,
688 NOCRED, &bp)) != 0)
689 goto error_exit;
690 fp = (struct fsinfo *)bp->b_data;
691 if (!bcmp(fp->fsisig1, "RRaA", 4)
692 && !bcmp(fp->fsisig2, "rrAa", 4)
693 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) {
694 pmp->pm_nxtfree = getulong(fp->fsinxtfree);
695 if (pmp->pm_nxtfree > pmp->pm_maxcluster)
696 pmp->pm_nxtfree = CLUST_FIRST;
697 } else
698 pmp->pm_fsinfo = 0;
699 brelse(bp);
700 bp = NULL;
701 }
702
703 /*
704 * Finish initializing pmp->pm_nxtfree (just in case the first few
705 * sectors aren't properly reserved in the FAT). This completes
706 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized
707 * value if there is no fsinfo. We will use pmp->pm_nxtfree
708 * internally even if there is no fsinfo.
709 */
710 if (pmp->pm_nxtfree < CLUST_FIRST)
711 pmp->pm_nxtfree = CLUST_FIRST;
712
713 /*
714 * Allocate memory for the bitmap of allocated clusters, and then
715 * fill it in.
716 */
717 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS)
718 * sizeof(*pmp->pm_inusemap),
719 M_MSDOSFSFAT, M_WAITOK);
720
721 /*
722 * fillinusemap() needs pm_devvp.
723 */
724 pmp->pm_devvp = devvp;
725 pmp->pm_dev = dev;
726
727 /*
728 * Have the inuse map filled in.
729 */
730 MSDOSFS_LOCK_MP(pmp);
731 error = fillinusemap(pmp);
732 MSDOSFS_UNLOCK_MP(pmp);
733 if (error != 0)
734 goto error_exit;
735
736 /*
737 * If they want fat updates to be synchronous then let them suffer
738 * the performance degradation in exchange for the on disk copy of
739 * the fat being correct just about all the time. I suppose this
740 * would be a good thing to turn on if the kernel is still flakey.
741 */
742 if (mp->mnt_flag & MNT_SYNCHRONOUS)
743 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT;
744
745 /*
746 * Finish up.
747 */
748 if (ronly)
749 pmp->pm_flags |= MSDOSFSMNT_RONLY;
750 else {
751 if ((error = markvoldirty(pmp, 1)) != 0) {
752 (void)markvoldirty(pmp, 0);
753 goto error_exit;
754 }
755 pmp->pm_fmod = 1;
756 }
757 mp->mnt_data = pmp;
758 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev);
759 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum;
760 MNT_ILOCK(mp);
761 mp->mnt_flag |= MNT_LOCAL;
762 MNT_IUNLOCK(mp);
763
764 if (pmp->pm_flags & MSDOSFS_LARGEFS)
765 msdosfs_fileno_init(mp);
766
767 return 0;
768
769 error_exit:
770 if (bp)
771 brelse(bp);
772 if (cp != NULL) {
773 DROP_GIANT();
774 g_topology_lock();
775 g_vfs_close(cp);
776 g_topology_unlock();
777 PICKUP_GIANT();
778 }
779 if (pmp) {
780 lockdestroy(&pmp->pm_fatlock);
781 if (pmp->pm_inusemap)
782 free(pmp->pm_inusemap, M_MSDOSFSFAT);
783 free(pmp, M_MSDOSFSMNT);
784 mp->mnt_data = NULL;
785 }
786 dev_rel(dev);
787 return (error);
788 }
789
790 /*
791 * Unmount the filesystem described by mp.
792 */
793 static int
794 msdosfs_unmount(struct mount *mp, int mntflags)
795 {
796 struct msdosfsmount *pmp;
797 int error, flags;
798
799 flags = 0;
800 if (mntflags & MNT_FORCE)
801 flags |= FORCECLOSE;
802 error = vflush(mp, 0, flags, curthread);
803 if (error && error != ENXIO)
804 return error;
805 pmp = VFSTOMSDOSFS(mp);
806 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) {
807 error = markvoldirty(pmp, 0);
808 if (error && error != ENXIO) {
809 (void)markvoldirty(pmp, 1);
810 return (error);
811 }
812 }
813 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) {
814 if (pmp->pm_w2u)
815 msdosfs_iconv->close(pmp->pm_w2u);
816 if (pmp->pm_u2w)
817 msdosfs_iconv->close(pmp->pm_u2w);
818 if (pmp->pm_d2u)
819 msdosfs_iconv->close(pmp->pm_d2u);
820 if (pmp->pm_u2d)
821 msdosfs_iconv->close(pmp->pm_u2d);
822 }
823
824 #ifdef MSDOSFS_DEBUG
825 {
826 struct vnode *vp = pmp->pm_devvp;
827 struct bufobj *bo;
828
829 bo = &vp->v_bufobj;
830 BO_LOCK(bo);
831 VI_LOCK(vp);
832 vn_printf(vp,
833 "msdosfs_umount(): just before calling VOP_CLOSE()\n");
834 printf("freef %p, freeb %p, mount %p\n",
835 TAILQ_NEXT(vp, v_actfreelist), vp->v_actfreelist.tqe_prev,
836 vp->v_mount);
837 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n",
838 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd),
839 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd),
840 vp->v_bufobj.bo_numoutput, vp->v_type);
841 VI_UNLOCK(vp);
842 BO_UNLOCK(bo);
843 }
844 #endif
845 DROP_GIANT();
846 if (pmp->pm_devvp->v_type == VCHR && pmp->pm_devvp->v_rdev != NULL)
847 pmp->pm_devvp->v_rdev->si_mountpt = NULL;
848 g_topology_lock();
849 g_vfs_close(pmp->pm_cp);
850 g_topology_unlock();
851 PICKUP_GIANT();
852 vrele(pmp->pm_devvp);
853 dev_rel(pmp->pm_dev);
854 free(pmp->pm_inusemap, M_MSDOSFSFAT);
855 if (pmp->pm_flags & MSDOSFS_LARGEFS)
856 msdosfs_fileno_free(mp);
857 lockdestroy(&pmp->pm_fatlock);
858 free(pmp, M_MSDOSFSMNT);
859 mp->mnt_data = NULL;
860 MNT_ILOCK(mp);
861 mp->mnt_flag &= ~MNT_LOCAL;
862 MNT_IUNLOCK(mp);
863 return (error);
864 }
865
866 static int
867 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp)
868 {
869 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
870 struct denode *ndep;
871 int error;
872
873 #ifdef MSDOSFS_DEBUG
874 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp);
875 #endif
876 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep);
877 if (error)
878 return (error);
879 *vpp = DETOV(ndep);
880 return (0);
881 }
882
883 static int
884 msdosfs_statfs(struct mount *mp, struct statfs *sbp)
885 {
886 struct msdosfsmount *pmp;
887
888 pmp = VFSTOMSDOSFS(mp);
889 sbp->f_bsize = pmp->pm_bpcluster;
890 sbp->f_iosize = pmp->pm_bpcluster;
891 sbp->f_blocks = pmp->pm_maxcluster + 1;
892 sbp->f_bfree = pmp->pm_freeclustercount;
893 sbp->f_bavail = pmp->pm_freeclustercount;
894 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */
895 sbp->f_ffree = 0; /* what to put in here? */
896 return (0);
897 }
898
899 /*
900 * If we have an FSInfo block, update it.
901 */
902 static int
903 msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor)
904 {
905 struct fsinfo *fp;
906 struct buf *bp;
907 int error;
908
909 MSDOSFS_LOCK_MP(pmp);
910 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) {
911 error = 0;
912 goto unlock;
913 }
914 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec,
915 NOCRED, &bp);
916 if (error != 0) {
917 brelse(bp);
918 goto unlock;
919 }
920 fp = (struct fsinfo *)bp->b_data;
921 putulong(fp->fsinfree, pmp->pm_freeclustercount);
922 putulong(fp->fsinxtfree, pmp->pm_nxtfree);
923 pmp->pm_flags &= ~MSDOSFS_FSIMOD;
924 if (waitfor == MNT_WAIT)
925 error = bwrite(bp);
926 else
927 bawrite(bp);
928 unlock:
929 MSDOSFS_UNLOCK_MP(pmp);
930 return (error);
931 }
932
933 static int
934 msdosfs_sync(struct mount *mp, int waitfor)
935 {
936 struct vnode *vp, *nvp;
937 struct thread *td;
938 struct denode *dep;
939 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
940 int error, allerror = 0;
941
942 td = curthread;
943
944 /*
945 * If we ever switch to not updating all of the fats all the time,
946 * this would be the place to update them from the first one.
947 */
948 if (pmp->pm_fmod != 0) {
949 if (pmp->pm_flags & MSDOSFSMNT_RONLY)
950 panic("msdosfs_sync: rofs mod");
951 else {
952 /* update fats here */
953 }
954 }
955 /*
956 * Write back each (modified) denode.
957 */
958 loop:
959 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) {
960 if (vp->v_type == VNON) {
961 VI_UNLOCK(vp);
962 continue;
963 }
964 dep = VTODE(vp);
965 if ((dep->de_flag &
966 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 &&
967 (vp->v_bufobj.bo_dirty.bv_cnt == 0 ||
968 waitfor == MNT_LAZY)) {
969 VI_UNLOCK(vp);
970 continue;
971 }
972 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td);
973 if (error) {
974 if (error == ENOENT)
975 goto loop;
976 continue;
977 }
978 error = VOP_FSYNC(vp, waitfor, td);
979 if (error)
980 allerror = error;
981 VOP_UNLOCK(vp, 0);
982 vrele(vp);
983 }
984
985 /*
986 * Flush filesystem control info.
987 */
988 if (waitfor != MNT_LAZY) {
989 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY);
990 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td);
991 if (error)
992 allerror = error;
993 VOP_UNLOCK(pmp->pm_devvp, 0);
994 }
995
996 error = msdosfs_fsiflush(pmp, waitfor);
997 if (error != 0)
998 allerror = error;
999 return (allerror);
1000 }
1001
1002 static int
1003 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp)
1004 {
1005 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp);
1006 struct defid *defhp = (struct defid *) fhp;
1007 struct denode *dep;
1008 int error;
1009
1010 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep);
1011 if (error) {
1012 *vpp = NULLVP;
1013 return (error);
1014 }
1015 *vpp = DETOV(dep);
1016 vnode_create_vobject(*vpp, dep->de_FileSize, curthread);
1017 return (0);
1018 }
1019
1020 static struct vfsops msdosfs_vfsops = {
1021 .vfs_fhtovp = msdosfs_fhtovp,
1022 .vfs_mount = msdosfs_mount,
1023 .vfs_cmount = msdosfs_cmount,
1024 .vfs_root = msdosfs_root,
1025 .vfs_statfs = msdosfs_statfs,
1026 .vfs_sync = msdosfs_sync,
1027 .vfs_unmount = msdosfs_unmount,
1028 };
1029
1030 VFS_SET(msdosfs_vfsops, msdosfs, 0);
1031 MODULE_VERSION(msdosfs, 1);
Cache object: d97f24aff509050943d1da75d2a42039
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