2/* $NetBSD: msdosfs_vnops.c,v 1.68 1998/02/10 14:10:04 mrg 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/resourcevar.h> /* defines plimit structure in proc struct */
55#include <sys/kernel.h>
56#include <sys/stat.h>
57#include <sys/buf.h>
58#include <sys/proc.h>
59#include <sys/mount.h>
60#include <sys/unistd.h>
61#include <sys/vnode.h>
62#include <sys/malloc.h>
63#include <sys/dirent.h>
64#include <sys/signalvar.h>
65
66#include <vm/vm.h>
67#include <vm/vm_extern.h>
68#include <vm/vm_zone.h>
69#include <vm/vnode_pager.h>
70
71#include <msdosfs/bpb.h>
72#include <msdosfs/direntry.h>
73#include <msdosfs/denode.h>
74#include <msdosfs/msdosfsmount.h>
75#include <msdosfs/fat.h>
76
77#define DOS_FILESIZE_MAX 0xffffffff
78
79/*
80 * Prototypes for MSDOSFS vnode operations
81 */
82static int msdosfs_create __P((struct vop_create_args *));
83static int msdosfs_mknod __P((struct vop_mknod_args *));
84static int msdosfs_close __P((struct vop_close_args *));
85static int msdosfs_access __P((struct vop_access_args *));
86static int msdosfs_getattr __P((struct vop_getattr_args *));
87static int msdosfs_setattr __P((struct vop_setattr_args *));
88static int msdosfs_read __P((struct vop_read_args *));
89static int msdosfs_write __P((struct vop_write_args *));
90static int msdosfs_fsync __P((struct vop_fsync_args *));
91static int msdosfs_remove __P((struct vop_remove_args *));
92static int msdosfs_link __P((struct vop_link_args *));
93static int msdosfs_rename __P((struct vop_rename_args *));
94static int msdosfs_mkdir __P((struct vop_mkdir_args *));
95static int msdosfs_rmdir __P((struct vop_rmdir_args *));
96static int msdosfs_symlink __P((struct vop_symlink_args *));
97static int msdosfs_readdir __P((struct vop_readdir_args *));
98static int msdosfs_bmap __P((struct vop_bmap_args *));
99static int msdosfs_strategy __P((struct vop_strategy_args *));
100static int msdosfs_print __P((struct vop_print_args *));
101static int msdosfs_pathconf __P((struct vop_pathconf_args *ap));
102static int msdosfs_getpages __P((struct vop_getpages_args *));
103static int msdosfs_putpages __P((struct vop_putpages_args *));
104
105/*
106 * Some general notes:
107 *
108 * In the ufs filesystem the inodes, superblocks, and indirect blocks are
109 * read/written using the vnode for the filesystem. Blocks that represent
110 * the contents of a file are read/written using the vnode for the file
111 * (including directories when they are read/written as files). This
112 * presents problems for the dos filesystem because data that should be in
113 * an inode (if dos had them) resides in the directory itself. Since we
114 * must update directory entries without the benefit of having the vnode
115 * for the directory we must use the vnode for the filesystem. This means
116 * that when a directory is actually read/written (via read, write, or
117 * readdir, or seek) we must use the vnode for the filesystem instead of
118 * the vnode for the directory as would happen in ufs. This is to insure we
119 * retreive the correct block from the buffer cache since the hash value is
120 * based upon the vnode address and the desired block number.
121 */
122
123/*
124 * Create a regular file. On entry the directory to contain the file being
125 * created is locked. We must release before we return. We must also free
126 * the pathname buffer pointed at by cnp->cn_pnbuf, always on error, or
127 * only if the SAVESTART bit in cn_flags is clear on success.
128 */
129static int
130msdosfs_create(ap)
131 struct vop_create_args /* {
132 struct vnode *a_dvp;
133 struct vnode **a_vpp;
134 struct componentname *a_cnp;
135 struct vattr *a_vap;
136 } */ *ap;
137{
138 struct componentname *cnp = ap->a_cnp;
139 struct denode ndirent;
140 struct denode *dep;
141 struct denode *pdep = VTODE(ap->a_dvp);
142 struct timespec ts;
143 int error;
144
145#ifdef MSDOSFS_DEBUG
146 printf("msdosfs_create(cnp %p, vap %p\n", cnp, ap->a_vap);
147#endif
148
149 /*
150 * If this is the root directory and there is no space left we
151 * can't do anything. This is because the root directory can not
152 * change size.
153 */
154 if (pdep->de_StartCluster == MSDOSFSROOT
155 && pdep->de_fndoffset >= pdep->de_FileSize) {
156 error = ENOSPC;
157 goto bad;
158 }
159
160 /*
161 * Create a directory entry for the file, then call createde() to
162 * have it installed. NOTE: DOS files are always executable. We
163 * use the absence of the owner write bit to make the file
164 * readonly.
165 */
166#ifdef DIAGNOSTIC
167 if ((cnp->cn_flags & HASBUF) == 0)
168 panic("msdosfs_create: no name");
169#endif
170 bzero(&ndirent, sizeof(ndirent));
171 error = uniqdosname(pdep, cnp, ndirent.de_Name);
172 if (error)
173 goto bad;
174
175 ndirent.de_Attributes = (ap->a_vap->va_mode & VWRITE) ?
176 ATTR_ARCHIVE : ATTR_ARCHIVE | ATTR_READONLY;
177 ndirent.de_LowerCase = 0;
178 ndirent.de_StartCluster = 0;
179 ndirent.de_FileSize = 0;
180 ndirent.de_dev = pdep->de_dev;
181 ndirent.de_devvp = pdep->de_devvp;
182 ndirent.de_pmp = pdep->de_pmp;
183 ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE;
184 getnanotime(&ts);
185 DETIMES(&ndirent, &ts, &ts, &ts);
186 error = createde(&ndirent, pdep, &dep, cnp);
187 if (error)
188 goto bad;
189 *ap->a_vpp = DETOV(dep);
190 return (0);
191
192bad:
193 return (error);
194}
195
196static int
197msdosfs_mknod(ap)
198 struct vop_mknod_args /* {
199 struct vnode *a_dvp;
200 struct vnode **a_vpp;
201 struct componentname *a_cnp;
202 struct vattr *a_vap;
203 } */ *ap;
204{
205
206 switch (ap->a_vap->va_type) {
207 case VDIR:
208 return (msdosfs_mkdir((struct vop_mkdir_args *)ap));
209 break;
210
211 case VREG:
212 return (msdosfs_create((struct vop_create_args *)ap));
213 break;
214
215 default:
216 return (EINVAL);
217 }
218 /* NOTREACHED */
219}
220
221static int
222msdosfs_close(ap)
223 struct vop_close_args /* {
224 struct vnode *a_vp;
225 int a_fflag;
226 struct ucred *a_cred;
227 struct proc *a_p;
228 } */ *ap;
229{
230 struct vnode *vp = ap->a_vp;
231 struct denode *dep = VTODE(vp);
232 struct timespec ts;
233
234 simple_lock(&vp->v_interlock);
235 if (vp->v_usecount > 1) {
236 getnanotime(&ts);
237 DETIMES(dep, &ts, &ts, &ts);
238 }
239 simple_unlock(&vp->v_interlock);
240 return 0;
241}
242
243static int
244msdosfs_access(ap)
245 struct vop_access_args /* {
246 struct vnode *a_vp;
247 int a_mode;
248 struct ucred *a_cred;
249 struct proc *a_p;
250 } */ *ap;
251{
252 struct vnode *vp = ap->a_vp;
253 struct denode *dep = VTODE(ap->a_vp);
254 struct msdosfsmount *pmp = dep->de_pmp;
255 struct ucred *cred = ap->a_cred;
256 mode_t mask, file_mode, mode = ap->a_mode;
257 register gid_t *gp;
258 int i;
259
260 file_mode = (S_IXUSR|S_IXGRP|S_IXOTH) | (S_IRUSR|S_IRGRP|S_IROTH) |
261 ((dep->de_Attributes & ATTR_READONLY) ? 0 : (S_IWUSR|S_IWGRP|S_IWOTH));
262 file_mode &= pmp->pm_mask;
263
264 /*
265 * Disallow write attempts on read-only file systems;
266 * unless the file is a socket, fifo, or a block or
267 * character device resident on the file system.
268 */
269 if (mode & VWRITE) {
270 switch (vp->v_type) {
271 case VDIR:
272 case VLNK:
273 case VREG:
274 if (vp->v_mount->mnt_flag & MNT_RDONLY)
275 return (EROFS);
276 break;
277 default:
278 break;
279 }
280 }
281
282 /* User id 0 always gets access. */
283 if (cred->cr_uid == 0)
284 return 0;
285
286 mask = 0;
287
288 /* Otherwise, check the owner. */
289 if (cred->cr_uid == pmp->pm_uid) {
290 if (mode & VEXEC)
291 mask |= S_IXUSR;
292 if (mode & VREAD)
293 mask |= S_IRUSR;
294 if (mode & VWRITE)
295 mask |= S_IWUSR;
296 return (file_mode & mask) == mask ? 0 : EACCES;
297 }
298
299 /* Otherwise, check the groups. */
300 for (i = 0, gp = cred->cr_groups; i < cred->cr_ngroups; i++, gp++)
301 if (pmp->pm_gid == *gp) {
302 if (mode & VEXEC)
303 mask |= S_IXGRP;
304 if (mode & VREAD)
305 mask |= S_IRGRP;
306 if (mode & VWRITE)
307 mask |= S_IWGRP;
308 return (file_mode & mask) == mask ? 0 : EACCES;
309 }
310
311 /* Otherwise, check everyone else. */
312 if (mode & VEXEC)
313 mask |= S_IXOTH;
314 if (mode & VREAD)
315 mask |= S_IROTH;
316 if (mode & VWRITE)
317 mask |= S_IWOTH;
318 return (file_mode & mask) == mask ? 0 : EACCES;
319}
320
321static int
322msdosfs_getattr(ap)
323 struct vop_getattr_args /* {
324 struct vnode *a_vp;
325 struct vattr *a_vap;
326 struct ucred *a_cred;
327 struct proc *a_p;
328 } */ *ap;
329{
330 struct denode *dep = VTODE(ap->a_vp);
331 struct msdosfsmount *pmp = dep->de_pmp;
332 struct vattr *vap = ap->a_vap;
333 mode_t mode;
334 struct timespec ts;
335 u_long dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry);
336 u_long fileid;
337
338 getnanotime(&ts);
339 DETIMES(dep, &ts, &ts, &ts);
340 vap->va_fsid = dev2udev(dep->de_dev);
341 /*
342 * The following computation of the fileid must be the same as that
343 * used in msdosfs_readdir() to compute d_fileno. If not, pwd
344 * doesn't work.
345 */
346 if (dep->de_Attributes & ATTR_DIRECTORY) {
347 fileid = cntobn(pmp, dep->de_StartCluster) * dirsperblk;
348 if (dep->de_StartCluster == MSDOSFSROOT)
349 fileid = 1;
350 } else {
351 fileid = cntobn(pmp, dep->de_dirclust) * dirsperblk;
352 if (dep->de_dirclust == MSDOSFSROOT)
353 fileid = roottobn(pmp, 0) * dirsperblk;
354 fileid += dep->de_diroffset / sizeof(struct direntry);
355 }
356 vap->va_fileid = fileid;
357 if ((dep->de_Attributes & ATTR_READONLY) == 0)
358 mode = S_IRWXU|S_IRWXG|S_IRWXO;
359 else
360 mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH;
361 vap->va_mode = mode & pmp->pm_mask;
362 vap->va_uid = pmp->pm_uid;
363 vap->va_gid = pmp->pm_gid;
364 vap->va_nlink = 1;
365 vap->va_rdev = 0;
366 vap->va_size = dep->de_FileSize;
367 dos2unixtime(dep->de_MDate, dep->de_MTime, 0, &vap->va_mtime);
368 if (pmp->pm_flags & MSDOSFSMNT_LONGNAME) {
369 dos2unixtime(dep->de_ADate, 0, 0, &vap->va_atime);
370 dos2unixtime(dep->de_CDate, dep->de_CTime, dep->de_CHun, &vap->va_ctime);
371 } else {
372 vap->va_atime = vap->va_mtime;
373 vap->va_ctime = vap->va_mtime;
374 }
375 vap->va_flags = 0;
376 if ((dep->de_Attributes & ATTR_ARCHIVE) == 0)
377 vap->va_flags |= SF_ARCHIVED;
378 vap->va_gen = 0;
379 vap->va_blocksize = pmp->pm_bpcluster;
380 vap->va_bytes =
381 (dep->de_FileSize + pmp->pm_crbomask) & ~pmp->pm_crbomask;
382 vap->va_type = ap->a_vp->v_type;
383 vap->va_filerev = dep->de_modrev;
384 return (0);
385}
386
387static int
388msdosfs_setattr(ap)
389 struct vop_setattr_args /* {
390 struct vnode *a_vp;
391 struct vattr *a_vap;
392 struct ucred *a_cred;
393 struct proc *a_p;
394 } */ *ap;
395{
396 struct vnode *vp = ap->a_vp;
397 struct denode *dep = VTODE(ap->a_vp);
398 struct msdosfsmount *pmp = dep->de_pmp;
399 struct vattr *vap = ap->a_vap;
400 struct ucred *cred = ap->a_cred;
401 int error = 0;
402
403#ifdef MSDOSFS_DEBUG
404 printf("msdosfs_setattr(): vp %p, vap %p, cred %p, p %p\n",
405 ap->a_vp, vap, cred, ap->a_p);
406#endif
407
408 /*
409 * Check for unsettable attributes.
410 */
411 if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) ||
412 (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) ||
413 (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) ||
414 (vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) {
415#ifdef MSDOSFS_DEBUG
416 printf("msdosfs_setattr(): returning EINVAL\n");
417 printf(" va_type %d, va_nlink %x, va_fsid %lx, va_fileid %lx\n",
418 vap->va_type, vap->va_nlink, vap->va_fsid, vap->va_fileid);
419 printf(" va_blocksize %lx, va_rdev %x, va_bytes %qx, va_gen %lx\n",
420 vap->va_blocksize, vap->va_rdev, vap->va_bytes, vap->va_gen);
421 printf(" va_uid %x, va_gid %x\n",
422 vap->va_uid, vap->va_gid);
423#endif
424 return (EINVAL);
425 }
426 if (vap->va_flags != VNOVAL) {
427 if (vp->v_mount->mnt_flag & MNT_RDONLY)
428 return (EROFS);
429 if (cred->cr_uid != pmp->pm_uid &&
430 (error = suser_xxx(cred, ap->a_p, PRISON_ROOT)))
431 return (error);
432 /*
433 * We are very inconsistent about handling unsupported
434 * attributes. We ignored the access time and the
435 * read and execute bits. We were strict for the other
436 * attributes.
437 *
438 * Here we are strict, stricter than ufs in not allowing
439 * users to attempt to set SF_SETTABLE bits or anyone to
440 * set unsupported bits. However, we ignore attempts to
441 * set ATTR_ARCHIVE for directories `cp -pr' from a more
442 * sensible file system attempts it a lot.
443 */
444 if (cred->cr_uid != 0) {
445 if (vap->va_flags & SF_SETTABLE)
446 return EPERM;
447 }
448 if (vap->va_flags & ~SF_ARCHIVED)
449 return EOPNOTSUPP;
450 if (vap->va_flags & SF_ARCHIVED)
451 dep->de_Attributes &= ~ATTR_ARCHIVE;
452 else if (!(dep->de_Attributes & ATTR_DIRECTORY))
453 dep->de_Attributes |= ATTR_ARCHIVE;
454 dep->de_flag |= DE_MODIFIED;
455 }
456
457 if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) {
458 uid_t uid;
459 gid_t gid;
460
461 if (vp->v_mount->mnt_flag & MNT_RDONLY)
462 return (EROFS);
463 uid = vap->va_uid;
464 if (uid == (uid_t)VNOVAL)
465 uid = pmp->pm_uid;
466 gid = vap->va_gid;
467 if (gid == (gid_t)VNOVAL)
468 gid = pmp->pm_gid;
469 if ((cred->cr_uid != pmp->pm_uid || uid != pmp->pm_uid ||
470 (gid != pmp->pm_gid && !groupmember(gid, cred))) &&
471 (error = suser_xxx(cred, ap->a_p, PRISON_ROOT)))
472 return error;
473 if (uid != pmp->pm_uid || gid != pmp->pm_gid)
474 return EINVAL;
475 }
476
477 if (vap->va_size != VNOVAL) {
478 /*
479 * Disallow write attempts on read-only file systems;
480 * unless the file is a socket, fifo, or a block or
481 * character device resident on the file system.
482 */
483 switch (vp->v_type) {
484 case VDIR:
485 return (EISDIR);
486 /* NOT REACHED */
487 case VLNK:
488 case VREG:
489 if (vp->v_mount->mnt_flag & MNT_RDONLY)
490 return (EROFS);
491 break;
492 default:
493 break;
494 }
495 error = detrunc(dep, vap->va_size, 0, cred, ap->a_p);
496 if (error)
497 return error;
498 }
499 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) {
500 if (vp->v_mount->mnt_flag & MNT_RDONLY)
501 return (EROFS);
502 if (cred->cr_uid != pmp->pm_uid &&
503 (error = suser_xxx(cred, ap->a_p, PRISON_ROOT)) &&
504 ((vap->va_vaflags & VA_UTIMES_NULL) == 0 ||
505 (error = VOP_ACCESS(ap->a_vp, VWRITE, cred, ap->a_p))))
506 return (error);
507 if (vp->v_type != VDIR) {
508 if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95) == 0 &&
509 vap->va_atime.tv_sec != VNOVAL)
510 unix2dostime(&vap->va_atime, &dep->de_ADate, NULL, NULL);
511 if (vap->va_mtime.tv_sec != VNOVAL)
512 unix2dostime(&vap->va_mtime, &dep->de_MDate, &dep->de_MTime, NULL);
513 dep->de_Attributes |= ATTR_ARCHIVE;
514 dep->de_flag |= DE_MODIFIED;
515 }
516 }
517 /*
518 * DOS files only have the ability to have their writability
519 * attribute set, so we use the owner write bit to set the readonly
520 * attribute.
521 */
522 if (vap->va_mode != (mode_t)VNOVAL) {
523 if (vp->v_mount->mnt_flag & MNT_RDONLY)
524 return (EROFS);
525 if (cred->cr_uid != pmp->pm_uid &&
526 (error = suser_xxx(cred, ap->a_p, PRISON_ROOT)))
527 return (error);
528 if (vp->v_type != VDIR) {
529 /* We ignore the read and execute bits. */
530 if (vap->va_mode & VWRITE)
531 dep->de_Attributes &= ~ATTR_READONLY;
532 else
533 dep->de_Attributes |= ATTR_READONLY;
534 dep->de_flag |= DE_MODIFIED;
535 }
536 }
537 return (deupdat(dep, 1));
538}
539
540static int
541msdosfs_read(ap)
542 struct vop_read_args /* {
543 struct vnode *a_vp;
544 struct uio *a_uio;
545 int a_ioflag;
546 struct ucred *a_cred;
547 } */ *ap;
548{
549 int error = 0;
550 int blsize;
551 int isadir;
552 int orig_resid;
553 u_int n;
554 u_long diff;
555 u_long on;
556 daddr_t lbn;
557 daddr_t rablock;
558 int rasize;
559 int seqcount;
560 struct buf *bp;
561 struct vnode *vp = ap->a_vp;
562 struct denode *dep = VTODE(vp);
563 struct msdosfsmount *pmp = dep->de_pmp;
564 struct uio *uio = ap->a_uio;
565
566 if (uio->uio_offset < 0)
567 return (EINVAL);
568
569 if ((uoff_t)uio->uio_offset > DOS_FILESIZE_MAX)
570 return (0);
571 /*
572 * If they didn't ask for any data, then we are done.
573 */
574 orig_resid = uio->uio_resid;
575 if (orig_resid <= 0)
576 return (0);
577
578 seqcount = ap->a_ioflag >> 16;
579
580 isadir = dep->de_Attributes & ATTR_DIRECTORY;
581 do {
582 if (uio->uio_offset >= dep->de_FileSize)
583 break;
584 lbn = de_cluster(pmp, uio->uio_offset);
585 /*
586 * If we are operating on a directory file then be sure to
587 * do i/o with the vnode for the filesystem instead of the
588 * vnode for the directory.
589 */
590 if (isadir) {
591 /* convert cluster # to block # */
592 error = pcbmap(dep, lbn, &lbn, 0, &blsize);
593 if (error == E2BIG) {
594 error = EINVAL;
595 break;
596 } else if (error)
597 break;
598 error = bread(pmp->pm_devvp, lbn, blsize, NOCRED, &bp);
599 } else {
600 blsize = pmp->pm_bpcluster;
601 rablock = lbn + 1;
602 if (seqcount > 1 &&
603 de_cn2off(pmp, rablock) < dep->de_FileSize) {
604 rasize = pmp->pm_bpcluster;
605 error = breadn(vp, lbn, blsize,
606 &rablock, &rasize, 1, NOCRED, &bp);
607 } else {
608 error = bread(vp, lbn, blsize, NOCRED, &bp);
609 }
610 }
611 if (error) {
612 brelse(bp);
613 break;
614 }
615 on = uio->uio_offset & pmp->pm_crbomask;
616 diff = pmp->pm_bpcluster - on;
617 n = diff > uio->uio_resid ? uio->uio_resid : diff;
618 diff = dep->de_FileSize - uio->uio_offset;
619 if (diff < n)
620 n = diff;
621 diff = blsize - bp->b_resid;
622 if (diff < n)
623 n = diff;
624 error = uiomove(bp->b_data + on, (int) n, uio);
625 brelse(bp);
626 } while (error == 0 && uio->uio_resid > 0 && n != 0);
627 if (!isadir && (error == 0 || uio->uio_resid != orig_resid) &&
628 (vp->v_mount->mnt_flag & MNT_NOATIME) == 0)
629 dep->de_flag |= DE_ACCESS;
630 return (error);
631}
632
633/*
634 * Write data to a file or directory.
635 */
636static int
637msdosfs_write(ap)
638 struct vop_write_args /* {
639 struct vnode *a_vp;
640 struct uio *a_uio;
641 int a_ioflag;
642 struct ucred *a_cred;
643 } */ *ap;
644{
645 int n;
646 int croffset;
647 int resid;
648 u_long osize;
649 int error = 0;
650 u_long count;
651 daddr_t bn, lastcn;
652 struct buf *bp;
653 int ioflag = ap->a_ioflag;
654 struct uio *uio = ap->a_uio;
655 struct proc *p = uio->uio_procp;
656 struct vnode *vp = ap->a_vp;
657 struct vnode *thisvp;
658 struct denode *dep = VTODE(vp);
659 struct msdosfsmount *pmp = dep->de_pmp;
660 struct ucred *cred = ap->a_cred;
661
662#ifdef MSDOSFS_DEBUG
663 printf("msdosfs_write(vp %p, uio %p, ioflag %x, cred %p\n",
664 vp, uio, ioflag, cred);
665 printf("msdosfs_write(): diroff %lu, dirclust %lu, startcluster %lu\n",
666 dep->de_diroffset, dep->de_dirclust, dep->de_StartCluster);
667#endif
668
669 switch (vp->v_type) {
670 case VREG:
671 if (ioflag & IO_APPEND)
672 uio->uio_offset = dep->de_FileSize;
673 thisvp = vp;
674 break;
675 case VDIR:
676 return EISDIR;
677 default:
678 panic("msdosfs_write(): bad file type");
679 }
680
681 if (uio->uio_offset < 0)
682 return (EFBIG);
683
684 if (uio->uio_resid == 0)
685 return (0);
686
687 /*
688 * If they've exceeded their filesize limit, tell them about it.
689 */
690 if (p &&
691 ((uoff_t)uio->uio_offset + uio->uio_resid >
692 p->p_rlimit[RLIMIT_FSIZE].rlim_cur)) {
693 psignal(p, SIGXFSZ);
694 return (EFBIG);
695 }
696
697 if ((uoff_t)uio->uio_offset + uio->uio_resid > DOS_FILESIZE_MAX)
698 return (EFBIG);
699
700 /*
701 * If the offset we are starting the write at is beyond the end of
702 * the file, then they've done a seek. Unix filesystems allow
703 * files with holes in them, DOS doesn't so we must fill the hole
704 * with zeroed blocks.
705 */
706 if (uio->uio_offset > dep->de_FileSize) {
707 error = deextend(dep, uio->uio_offset, cred);
708 if (error)
709 return (error);
710 }
711
712 /*
713 * Remember some values in case the write fails.
714 */
715 resid = uio->uio_resid;
716 osize = dep->de_FileSize;
717
718 /*
719 * If we write beyond the end of the file, extend it to its ultimate
720 * size ahead of the time to hopefully get a contiguous area.
721 */
722 if (uio->uio_offset + resid > osize) {
723 count = de_clcount(pmp, uio->uio_offset + resid) -
724 de_clcount(pmp, osize);
725 error = extendfile(dep, count, NULL, NULL, 0);
726 if (error && (error != ENOSPC || (ioflag & IO_UNIT)))
727 goto errexit;
728 lastcn = dep->de_fc[FC_LASTFC].fc_frcn;
729 } else
730 lastcn = de_clcount(pmp, osize) - 1;
731
732 do {
733 if (de_cluster(pmp, uio->uio_offset) > lastcn) {
734 error = ENOSPC;
735 break;
736 }
737
738 croffset = uio->uio_offset & pmp->pm_crbomask;
739 n = min(uio->uio_resid, pmp->pm_bpcluster - croffset);
740 if (uio->uio_offset + n > dep->de_FileSize) {
741 dep->de_FileSize = uio->uio_offset + n;
742 /* The object size needs to be set before buffer is allocated */
743 vnode_pager_setsize(vp, dep->de_FileSize);
744 }
745
746 bn = de_cluster(pmp, uio->uio_offset);
747 if ((uio->uio_offset & pmp->pm_crbomask) == 0
748 && (de_cluster(pmp, uio->uio_offset + uio->uio_resid)
749 > de_cluster(pmp, uio->uio_offset)
750 || uio->uio_offset + uio->uio_resid >= dep->de_FileSize)) {
751 /*
752 * If either the whole cluster gets written,
753 * or we write the cluster from its start beyond EOF,
754 * then no need to read data from disk.
755 */
756 bp = getblk(thisvp, bn, pmp->pm_bpcluster, 0, 0);
757 clrbuf(bp);
758 /*
759 * Do the bmap now, since pcbmap needs buffers
760 * for the fat table. (see msdosfs_strategy)
761 */
762 if (bp->b_blkno == bp->b_lblkno) {
763 error = pcbmap(dep, bp->b_lblkno, &bp->b_blkno,
764 0, 0);
765 if (error)
766 bp->b_blkno = -1;
767 }
768 if (bp->b_blkno == -1) {
769 brelse(bp);
770 if (!error)
771 error = EIO; /* XXX */
772 break;
773 }
774 } else {
775 /*
776 * The block we need to write into exists, so read it in.
777 */
778 error = bread(thisvp, bn, pmp->pm_bpcluster, cred, &bp);
779 if (error) {
780 brelse(bp);
781 break;
782 }
783 }
784
785 /*
786 * Should these vnode_pager_* functions be done on dir
787 * files?
788 */
789
790 /*
791 * Copy the data from user space into the buf header.
792 */
793 error = uiomove(bp->b_data + croffset, n, uio);
794 if (error) {
795 brelse(bp);
796 break;
797 }
798
799 /*
800 * If they want this synchronous then write it and wait for
801 * it. Otherwise, if on a cluster boundary write it
802 * asynchronously so we can move on to the next block
803 * without delay. Otherwise do a delayed write because we
804 * may want to write somemore into the block later.
805 */
806 if (ioflag & IO_SYNC)
807 (void) bwrite(bp);
808 else if (n + croffset == pmp->pm_bpcluster)
809 bawrite(bp);
810 else
811 bdwrite(bp);
812 dep->de_flag |= DE_UPDATE;
813 } while (error == 0 && uio->uio_resid > 0);
814
815 /*
816 * If the write failed and they want us to, truncate the file back
817 * to the size it was before the write was attempted.
818 */
819errexit:
820 if (error) {
821 if (ioflag & IO_UNIT) {
822 detrunc(dep, osize, ioflag & IO_SYNC, NOCRED, NULL);
823 uio->uio_offset -= resid - uio->uio_resid;
824 uio->uio_resid = resid;
825 } else {
826 detrunc(dep, dep->de_FileSize, ioflag & IO_SYNC, NOCRED, NULL);
827 if (uio->uio_resid != resid)
828 error = 0;
829 }
830 } else if (ioflag & IO_SYNC)
831 error = deupdat(dep, 1);
832 return (error);
833}
834
835/*
836 * Flush the blocks of a file to disk.
837 *
838 * This function is worthless for vnodes that represent directories. Maybe we
839 * could just do a sync if they try an fsync on a directory file.
840 */
841static int
842msdosfs_fsync(ap)
843 struct vop_fsync_args /* {
844 struct vnode *a_vp;
845 struct ucred *a_cred;
846 int a_waitfor;
847 struct proc *a_p;
848 } */ *ap;
849{
850 struct vnode *vp = ap->a_vp;
851 int s;
852 struct buf *bp, *nbp;
853
854 /*
855 * Flush all dirty buffers associated with a vnode.
856 */
857loop:
858 s = splbio();
859 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
860 nbp = TAILQ_NEXT(bp, b_vnbufs);
861 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT))
862 continue;
863 if ((bp->b_flags & B_DELWRI) == 0)
864 panic("msdosfs_fsync: not dirty");
865 bremfree(bp);
866 splx(s);
867 (void) bwrite(bp);
868 goto loop;
869 }
870 while (vp->v_numoutput) {
871 vp->v_flag |= VBWAIT;
872 (void) tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "msdosfsn", 0);
873 }
874#ifdef DIAGNOSTIC
875 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) {
876 vprint("msdosfs_fsync: dirty", vp);
877 goto loop;
878 }
879#endif
880 splx(s);
881 return (deupdat(VTODE(vp), ap->a_waitfor == MNT_WAIT));
882}
883
884static int
885msdosfs_remove(ap)
886 struct vop_remove_args /* {
887 struct vnode *a_dvp;
888 struct vnode *a_vp;
889 struct componentname *a_cnp;
890 } */ *ap;
891{
892 struct denode *dep = VTODE(ap->a_vp);
893 struct denode *ddep = VTODE(ap->a_dvp);
894 int error;
895
896 if (ap->a_vp->v_type == VDIR)
897 error = EPERM;
898 else
899 error = removede(ddep, dep);
900#ifdef MSDOSFS_DEBUG
901 printf("msdosfs_remove(), dep %p, v_usecount %d\n", dep, ap->a_vp->v_usecount);
902#endif
903 return (error);
904}
905
906/*
907 * DOS filesystems don't know what links are. But since we already called
908 * msdosfs_lookup() with create and lockparent, the parent is locked so we
909 * have to free it before we return the error.
910 */
911static int
912msdosfs_link(ap)
913 struct vop_link_args /* {
914 struct vnode *a_tdvp;
915 struct vnode *a_vp;
916 struct componentname *a_cnp;
917 } */ *ap;
918{
919 return (EOPNOTSUPP);
920}
921
922/*
923 * Renames on files require moving the denode to a new hash queue since the
924 * denode's location is used to compute which hash queue to put the file
925 * in. Unless it is a rename in place. For example "mv a b".
926 *
927 * What follows is the basic algorithm:
928 *
929 * if (file move) {
930 * if (dest file exists) {
931 * remove dest file
932 * }
933 * if (dest and src in same directory) {
934 * rewrite name in existing directory slot
935 * } else {
936 * write new entry in dest directory
937 * update offset and dirclust in denode
938 * move denode to new hash chain
939 * clear old directory entry
940 * }
941 * } else {
942 * directory move
943 * if (dest directory exists) {
944 * if (dest is not empty) {
945 * return ENOTEMPTY
946 * }
947 * remove dest directory
948 * }
949 * if (dest and src in same directory) {
950 * rewrite name in existing entry
951 * } else {
952 * be sure dest is not a child of src directory
953 * write entry in dest directory
954 * update "." and ".." in moved directory
955 * clear old directory entry for moved directory
956 * }
957 * }
958 *
959 * On entry:
960 * source's parent directory is unlocked
961 * source file or directory is unlocked
962 * destination's parent directory is locked
963 * destination file or directory is locked if it exists
964 *
965 * On exit:
966 * all denodes should be released
967 *
968 * Notes:
969 * I'm not sure how the memory containing the pathnames pointed at by the
970 * componentname structures is freed, there may be some memory bleeding
971 * for each rename done.
972 */
973static int
974msdosfs_rename(ap)
975 struct vop_rename_args /* {
976 struct vnode *a_fdvp;
977 struct vnode *a_fvp;
978 struct componentname *a_fcnp;
979 struct vnode *a_tdvp;
980 struct vnode *a_tvp;
981 struct componentname *a_tcnp;
982 } */ *ap;
983{
984 struct vnode *tdvp = ap->a_tdvp;
985 struct vnode *fvp = ap->a_fvp;
986 struct vnode *fdvp = ap->a_fdvp;
987 struct vnode *tvp = ap->a_tvp;
988 struct componentname *tcnp = ap->a_tcnp;
989 struct componentname *fcnp = ap->a_fcnp;
990 struct proc *p = fcnp->cn_proc;
991 struct denode *ip, *xp, *dp, *zp;
992 u_char toname[11], oldname[11];
993 u_long from_diroffset, to_diroffset;
994 u_char to_count;
995 int doingdirectory = 0, newparent = 0;
996 int error;
997 u_long cn;
998 daddr_t bn;
999 struct denode *fddep; /* from file's parent directory */
1000 struct denode *fdep; /* from file or directory */
1001 struct denode *tddep; /* to file's parent directory */
1002 struct denode *tdep; /* to file or directory */
1003 struct msdosfsmount *pmp;
1004 struct direntry *dotdotp;
1005 struct buf *bp;
1006
1007 fddep = VTODE(ap->a_fdvp);
1008 fdep = VTODE(ap->a_fvp);
1009 tddep = VTODE(ap->a_tdvp);
1010 tdep = tvp ? VTODE(tvp) : NULL;
1011 pmp = fddep->de_pmp;
1012
1013 pmp = VFSTOMSDOSFS(fdvp->v_mount);
1014
1015#ifdef DIAGNOSTIC
1016 if ((tcnp->cn_flags & HASBUF) == 0 ||
1017 (fcnp->cn_flags & HASBUF) == 0)
1018 panic("msdosfs_rename: no name");
1019#endif
1020 /*
1021 * Check for cross-device rename.
1022 */
1023 if ((fvp->v_mount != tdvp->v_mount) ||
1024 (tvp && (fvp->v_mount != tvp->v_mount))) {
1025 error = EXDEV;
1026abortit:
1027 if (tdvp == tvp)
1028 vrele(tdvp);
1029 else
1030 vput(tdvp);
1031 if (tvp)
1032 vput(tvp);
1033 vrele(fdvp);
1034 vrele(fvp);
1035 return (error);
1036 }
1037
1038 /*
1039 * If source and dest are the same, do nothing.
1040 */
1041 if (tvp == fvp) {
1042 error = 0;
1043 goto abortit;
1044 }
1045
1046 error = vn_lock(fvp, LK_EXCLUSIVE, p);
1047 if (error)
1048 goto abortit;
1049 dp = VTODE(fdvp);
1050 ip = VTODE(fvp);
1051
1052 /*
1053 * Be sure we are not renaming ".", "..", or an alias of ".". This
1054 * leads to a crippled directory tree. It's pretty tough to do a
1055 * "ls" or "pwd" with the "." directory entry missing, and "cd .."
1056 * doesn't work if the ".." entry is missing.
1057 */
1058 if (ip->de_Attributes & ATTR_DIRECTORY) {
1059 /*
1060 * Avoid ".", "..", and aliases of "." for obvious reasons.
1061 */
1062 if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') ||
1063 dp == ip ||
1064 (fcnp->cn_flags & ISDOTDOT) ||
1065 (tcnp->cn_flags & ISDOTDOT) ||
1066 (ip->de_flag & DE_RENAME)) {
1067 VOP_UNLOCK(fvp, 0, p);
1068 error = EINVAL;
1069 goto abortit;
1070 }
1071 ip->de_flag |= DE_RENAME;
1072 doingdirectory++;
1073 }
1074
1075 /*
1076 * When the target exists, both the directory
1077 * and target vnodes are returned locked.
1078 */
1079 dp = VTODE(tdvp);
1080 xp = tvp ? VTODE(tvp) : NULL;
1081 /*
1082 * Remember direntry place to use for destination
1083 */
1084 to_diroffset = dp->de_fndoffset;
1085 to_count = dp->de_fndcnt;
1086
1087 /*
1088 * If ".." must be changed (ie the directory gets a new
1089 * parent) then the source directory must not be in the
1090 * directory heirarchy above the target, as this would
1091 * orphan everything below the source directory. Also
1092 * the user must have write permission in the source so
1093 * as to be able to change "..". We must repeat the call
1094 * to namei, as the parent directory is unlocked by the
1095 * call to doscheckpath().
1096 */
1097 error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_proc);
1098 VOP_UNLOCK(fvp, 0, p);
1099 if (VTODE(fdvp)->de_StartCluster != VTODE(tdvp)->de_StartCluster)
1100 newparent = 1;
1101 vrele(fdvp);
1102 if (doingdirectory && newparent) {
1103 if (error) /* write access check above */
1104 goto bad;
1105 if (xp != NULL)
1106 vput(tvp);
1107 /*
1108 * doscheckpath() vput()'s dp,
1109 * so we have to do a relookup afterwards
1110 */
1111 error = doscheckpath(ip, dp);
1112 if (error)
1113 goto out;
1114 if ((tcnp->cn_flags & SAVESTART) == 0)
1115 panic("msdosfs_rename: lost to startdir");
1116 error = relookup(tdvp, &tvp, tcnp);
1117 if (error)
1118 goto out;
1119 dp = VTODE(tdvp);
1120 xp = tvp ? VTODE(tvp) : NULL;
1121 }
1122
1123 if (xp != NULL) {
1124 /*
1125 * Target must be empty if a directory and have no links
1126 * to it. Also, ensure source and target are compatible
1127 * (both directories, or both not directories).
1128 */
1129 if (xp->de_Attributes & ATTR_DIRECTORY) {
1130 if (!dosdirempty(xp)) {
1131 error = ENOTEMPTY;
1132 goto bad;
1133 }
1134 if (!doingdirectory) {
1135 error = ENOTDIR;
1136 goto bad;
1137 }
1138 cache_purge(tdvp);
1139 } else if (doingdirectory) {
1140 error = EISDIR;
1141 goto bad;
1142 }
1143 error = removede(dp, xp);
1144 if (error)
1145 goto bad;
1146 vput(tvp);
1147 xp = NULL;
1148 }
1149
1150 /*
1151 * Convert the filename in tcnp into a dos filename. We copy this
1152 * into the denode and directory entry for the destination
1153 * file/directory.
1154 */
1155 error = uniqdosname(VTODE(tdvp), tcnp, toname);
1156 if (error)
1157 goto abortit;
1158
1159 /*
1160 * Since from wasn't locked at various places above,
1161 * have to do a relookup here.
1162 */
1163 fcnp->cn_flags &= ~MODMASK;
1164 fcnp->cn_flags |= LOCKPARENT | LOCKLEAF;
1165 if ((fcnp->cn_flags & SAVESTART) == 0)
1166 panic("msdosfs_rename: lost from startdir");
1167 if (!newparent)
1168 VOP_UNLOCK(tdvp, 0, p);
1169 (void) relookup(fdvp, &fvp, fcnp);
1170 if (fvp == NULL) {
1171 /*
1172 * From name has disappeared.
1173 */
1174 if (doingdirectory)
1175 panic("rename: lost dir entry");
1176 vrele(ap->a_fvp);
1177 if (newparent)
1178 VOP_UNLOCK(tdvp, 0, p);
1179 vrele(tdvp);
1180 return 0;
1181 }
1182 xp = VTODE(fvp);
1183 zp = VTODE(fdvp);
1184 from_diroffset = zp->de_fndoffset;
1185
1186 /*
1187 * Ensure that the directory entry still exists and has not
1188 * changed till now. If the source is a file the entry may
1189 * have been unlinked or renamed. In either case there is
1190 * no further work to be done. If the source is a directory
1191 * then it cannot have been rmdir'ed or renamed; this is
1192 * prohibited by the DE_RENAME flag.
1193 */
1194 if (xp != ip) {
1195 if (doingdirectory)
1196 panic("rename: lost dir entry");
1197 vrele(ap->a_fvp);
1198 VOP_UNLOCK(fvp, 0, p);
1199 if (newparent)
1200 VOP_UNLOCK(fdvp, 0, p);
1201 xp = NULL;
1202 } else {
1203 vrele(fvp);
1204 xp = NULL;
1205
1206 /*
1207 * First write a new entry in the destination
1208 * directory and mark the entry in the source directory
1209 * as deleted. Then move the denode to the correct hash
1210 * chain for its new location in the filesystem. And, if
1211 * we moved a directory, then update its .. entry to point
1212 * to the new parent directory.
1213 */
1214 bcopy(ip->de_Name, oldname, 11);
1215 bcopy(toname, ip->de_Name, 11); /* update denode */
1216 dp->de_fndoffset = to_diroffset;
1217 dp->de_fndcnt = to_count;
1218 error = createde(ip, dp, (struct denode **)0, tcnp);
1219 if (error) {
1220 bcopy(oldname, ip->de_Name, 11);
1221 if (newparent)
1222 VOP_UNLOCK(fdvp, 0, p);
1223 VOP_UNLOCK(fvp, 0, p);
1224 goto bad;
1225 }
1226 ip->de_refcnt++;
1227 zp->de_fndoffset = from_diroffset;
1228 error = removede(zp, ip);
1229 if (error) {
1230 /* XXX should really panic here, fs is corrupt */
1231 if (newparent)
1232 VOP_UNLOCK(fdvp, 0, p);
1233 VOP_UNLOCK(fvp, 0, p);
1234 goto bad;
1235 }
1236 if (!doingdirectory) {
1237 error = pcbmap(dp, de_cluster(pmp, to_diroffset), 0,
1238 &ip->de_dirclust, 0);
1239 if (error) {
1240 /* XXX should really panic here, fs is corrupt */
1241 if (newparent)
1242 VOP_UNLOCK(fdvp, 0, p);
1243 VOP_UNLOCK(fvp, 0, p);
1244 goto bad;
1245 }
1246 if (ip->de_dirclust == MSDOSFSROOT)
1247 ip->de_diroffset = to_diroffset;
1248 else
1249 ip->de_diroffset = to_diroffset & pmp->pm_crbomask;
1250 }
1251 reinsert(ip);
1252 if (newparent)
1253 VOP_UNLOCK(fdvp, 0, p);
1254 }
1255
1256 /*
1257 * If we moved a directory to a new parent directory, then we must
1258 * fixup the ".." entry in the moved directory.
1259 */
1260 if (doingdirectory && newparent) {
1261 cn = ip->de_StartCluster;
1262 if (cn == MSDOSFSROOT) {
1263 /* this should never happen */
1264 panic("msdosfs_rename(): updating .. in root directory?");
1265 } else
1266 bn = cntobn(pmp, cn);
1267 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
1268 NOCRED, &bp);
1269 if (error) {
1270 /* XXX should really panic here, fs is corrupt */
1271 brelse(bp);
1272 VOP_UNLOCK(fvp, 0, p);
1273 goto bad;
1274 }
1275 dotdotp = (struct direntry *)bp->b_data + 1;
1276 putushort(dotdotp->deStartCluster, dp->de_StartCluster);
1277 if (FAT32(pmp))
1278 putushort(dotdotp->deHighClust, dp->de_StartCluster >> 16);
1279 error = bwrite(bp);
1280 if (error) {
1281 /* XXX should really panic here, fs is corrupt */
1282 VOP_UNLOCK(fvp, 0, p);
1283 goto bad;
1284 }
1285 }
1286
1287 VOP_UNLOCK(fvp, 0, p);
1288bad:
1289 if (xp)
1290 vput(tvp);
1291 vput(tdvp);
1292out:
1293 ip->de_flag &= ~DE_RENAME;
1294 vrele(fdvp);
1295 vrele(fvp);
1296 return (error);
1297
1298}
1299
1300static struct {
1301 struct direntry dot;
1302 struct direntry dotdot;
1303} dosdirtemplate = {
1304 { ". ", " ", /* the . entry */
1305 ATTR_DIRECTORY, /* file attribute */
1306 0, /* reserved */
1307 0, { 0, 0 }, { 0, 0 }, /* create time & date */
1308 { 0, 0 }, /* access date */
1309 { 0, 0 }, /* high bits of start cluster */
1310 { 210, 4 }, { 210, 4 }, /* modify time & date */
1311 { 0, 0 }, /* startcluster */
1312 { 0, 0, 0, 0 } /* filesize */
1313 },
1314 { ".. ", " ", /* the .. entry */
1315 ATTR_DIRECTORY, /* file attribute */
1316 0, /* reserved */
1317 0, { 0, 0 }, { 0, 0 }, /* create time & date */
1318 { 0, 0 }, /* access date */
1319 { 0, 0 }, /* high bits of start cluster */
1320 { 210, 4 }, { 210, 4 }, /* modify time & date */
1321 { 0, 0 }, /* startcluster */
1322 { 0, 0, 0, 0 } /* filesize */
1323 }
1324};
1325
1326static int
1327msdosfs_mkdir(ap)
1328 struct vop_mkdir_args /* {
1329 struct vnode *a_dvp;
1330 struvt vnode **a_vpp;
1331 struvt componentname *a_cnp;
1332 struct vattr *a_vap;
1333 } */ *ap;
1334{
1335 struct componentname *cnp = ap->a_cnp;
1336 struct denode *dep;
1337 struct denode *pdep = VTODE(ap->a_dvp);
1338 struct direntry *denp;
1339 struct msdosfsmount *pmp = pdep->de_pmp;
1340 struct buf *bp;
1341 u_long newcluster, pcl;
1342 int bn;
1343 int error;
1344 struct denode ndirent;
1345 struct timespec ts;
1346
1347 /*
1348 * If this is the root directory and there is no space left we
1349 * can't do anything. This is because the root directory can not
1350 * change size.
1351 */
1352 if (pdep->de_StartCluster == MSDOSFSROOT
1353 && pdep->de_fndoffset >= pdep->de_FileSize) {
1354 error = ENOSPC;
1355 goto bad2;
1356 }
1357
1358 /*
1359 * Allocate a cluster to hold the about to be created directory.
1360 */
1361 error = clusteralloc(pmp, 0, 1, CLUST_EOFE, &newcluster, NULL);
1362 if (error)
1363 goto bad2;
1364
1365 bzero(&ndirent, sizeof(ndirent));
1366 ndirent.de_pmp = pmp;
1367 ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE;
1368 getnanotime(&ts);
1369 DETIMES(&ndirent, &ts, &ts, &ts);
1370
1371 /*
1372 * Now fill the cluster with the "." and ".." entries. And write
1373 * the cluster to disk. This way it is there for the parent
1374 * directory to be pointing at if there were a crash.
1375 */
1376 bn = cntobn(pmp, newcluster);
1377 /* always succeeds */
1378 bp = getblk(pmp->pm_devvp, bn, pmp->pm_bpcluster, 0, 0);
1379 bzero(bp->b_data, pmp->pm_bpcluster);
1380 bcopy(&dosdirtemplate, bp->b_data, sizeof dosdirtemplate);
1381 denp = (struct direntry *)bp->b_data;
1382 putushort(denp[0].deStartCluster, newcluster);
1383 putushort(denp[0].deCDate, ndirent.de_CDate);
1384 putushort(denp[0].deCTime, ndirent.de_CTime);
1385 denp[0].deCHundredth = ndirent.de_CHun;
1386 putushort(denp[0].deADate, ndirent.de_ADate);
1387 putushort(denp[0].deMDate, ndirent.de_MDate);
1388 putushort(denp[0].deMTime, ndirent.de_MTime);
1389 pcl = pdep->de_StartCluster;
1390 if (FAT32(pmp) && pcl == pmp->pm_rootdirblk)
1391 pcl = 0;
1392 putushort(denp[1].deStartCluster, pcl);
1393 putushort(denp[1].deCDate, ndirent.de_CDate);
1394 putushort(denp[1].deCTime, ndirent.de_CTime);
1395 denp[1].deCHundredth = ndirent.de_CHun;
1396 putushort(denp[1].deADate, ndirent.de_ADate);
1397 putushort(denp[1].deMDate, ndirent.de_MDate);
1398 putushort(denp[1].deMTime, ndirent.de_MTime);
1399 if (FAT32(pmp)) {
1400 putushort(denp[0].deHighClust, newcluster >> 16);
1401 putushort(denp[1].deHighClust, pdep->de_StartCluster >> 16);
1402 }
1403
1404 error = bwrite(bp);
1405 if (error)
1406 goto bad;
1407
1408 /*
1409 * Now build up a directory entry pointing to the newly allocated
1410 * cluster. This will be written to an empty slot in the parent
1411 * directory.
1412 */
1413#ifdef DIAGNOSTIC
1414 if ((cnp->cn_flags & HASBUF) == 0)
1415 panic("msdosfs_mkdir: no name");
1416#endif
1417 error = uniqdosname(pdep, cnp, ndirent.de_Name);
1418 if (error)
1419 goto bad;
1420
1421 ndirent.de_Attributes = ATTR_DIRECTORY;
1422 ndirent.de_LowerCase = 0;
1423 ndirent.de_StartCluster = newcluster;
1424 ndirent.de_FileSize = 0;
1425 ndirent.de_dev = pdep->de_dev;
1426 ndirent.de_devvp = pdep->de_devvp;
1427 error = createde(&ndirent, pdep, &dep, cnp);
1428 if (error)
1429 goto bad;
1430 *ap->a_vpp = DETOV(dep);
1431 return (0);
1432
1433bad:
1434 clusterfree(pmp, newcluster, NULL);
1435bad2:
1436 return (error);
1437}
1438
1439static int
1440msdosfs_rmdir(ap)
1441 struct vop_rmdir_args /* {
1442 struct vnode *a_dvp;
1443 struct vnode *a_vp;
1444 struct componentname *a_cnp;
1445 } */ *ap;
1446{
1447 register struct vnode *vp = ap->a_vp;
1448 register struct vnode *dvp = ap->a_dvp;
1449 register struct componentname *cnp = ap->a_cnp;
1450 register struct denode *ip, *dp;
1451 struct proc *p = cnp->cn_proc;
1452 int error;
1453
1454 ip = VTODE(vp);
1455 dp = VTODE(dvp);
1456
1457 /*
1458 * Verify the directory is empty (and valid).
1459 * (Rmdir ".." won't be valid since
1460 * ".." will contain a reference to
1461 * the current directory and thus be
1462 * non-empty.)
1463 */
1464 error = 0;
1465 if (!dosdirempty(ip) || ip->de_flag & DE_RENAME) {
1466 error = ENOTEMPTY;
1467 goto out;
1468 }
1469 /*
1470 * Delete the entry from the directory. For dos filesystems this
1471 * gets rid of the directory entry on disk, the in memory copy
1472 * still exists but the de_refcnt is <= 0. This prevents it from
1473 * being found by deget(). When the vput() on dep is done we give
1474 * up access and eventually msdosfs_reclaim() will be called which
1475 * will remove it from the denode cache.
1476 */
1477 error = removede(dp, ip);
1478 if (error)
1479 goto out;
1480 /*
1481 * This is where we decrement the link count in the parent
1482 * directory. Since dos filesystems don't do this we just purge
1483 * the name cache.
1484 */
1485 cache_purge(dvp);
1486 VOP_UNLOCK(dvp, 0, p);
1487 /*
1488 * Truncate the directory that is being deleted.
1489 */
1490 error = detrunc(ip, (u_long)0, IO_SYNC, cnp->cn_cred, p);
1491 cache_purge(vp);
1492
1493 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, p);
1494out:
1495 return (error);
1496}
1497
1498/*
1499 * DOS filesystems don't know what symlinks are.
1500 */
1501static int
1502msdosfs_symlink(ap)
1503 struct vop_symlink_args /* {
1504 struct vnode *a_dvp;
1505 struct vnode **a_vpp;
1506 struct componentname *a_cnp;
1507 struct vattr *a_vap;
1508 char *a_target;
1509 } */ *ap;
1510{
1511 return (EOPNOTSUPP);
1512}
1513
1514static int
1515msdosfs_readdir(ap)
1516 struct vop_readdir_args /* {
1517 struct vnode *a_vp;
1518 struct uio *a_uio;
1519 struct ucred *a_cred;
1520 int *a_eofflag;
1521 int *a_ncookies;
1522 u_long **a_cookies;
1523 } */ *ap;
1524{
1525 int error = 0;
1526 int diff;
1527 long n;
1528 int blsize;
1529 long on;
1530 u_long cn;
1531 u_long fileno;
1532 u_long dirsperblk;
1533 long bias = 0;
1534 daddr_t bn, lbn;
1535 struct buf *bp;
1536 struct denode *dep = VTODE(ap->a_vp);
1537 struct msdosfsmount *pmp = dep->de_pmp;
1538 struct direntry *dentp;
1539 struct dirent dirbuf;
1540 struct uio *uio = ap->a_uio;
1541 u_long *cookies = NULL;
1542 int ncookies = 0;
1543 off_t offset, off;
1544 int chksum = -1;
1545
1546#ifdef MSDOSFS_DEBUG
1547 printf("msdosfs_readdir(): vp %p, uio %p, cred %p, eofflagp %p\n",
1548 ap->a_vp, uio, ap->a_cred, ap->a_eofflag);
1549#endif
1550
1551 /*
1552 * msdosfs_readdir() won't operate properly on regular files since
1553 * it does i/o only with the the filesystem vnode, and hence can
1554 * retrieve the wrong block from the buffer cache for a plain file.
1555 * So, fail attempts to readdir() on a plain file.
1556 */
1557 if ((dep->de_Attributes & ATTR_DIRECTORY) == 0)
1558 return (ENOTDIR);
1559
1560 /*
1561 * To be safe, initialize dirbuf
1562 */
1563 bzero(dirbuf.d_name, sizeof(dirbuf.d_name));
1564
1565 /*
1566 * If the user buffer is smaller than the size of one dos directory
1567 * entry or the file offset is not a multiple of the size of a
1568 * directory entry, then we fail the read.
1569 */
1570 off = offset = uio->uio_offset;
1571 if (uio->uio_resid < sizeof(struct direntry) ||
1572 (offset & (sizeof(struct direntry) - 1)))
1573 return (EINVAL);
1574
1575 if (ap->a_ncookies) {
1576 ncookies = uio->uio_resid / 16;
1577 MALLOC(cookies, u_long *, ncookies * sizeof(u_long), M_TEMP,
1578 M_WAITOK);
1579 *ap->a_cookies = cookies;
1580 *ap->a_ncookies = ncookies;
1581 }
1582
1583 dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry);
1584
1585 /*
1586 * If they are reading from the root directory then, we simulate
1587 * the . and .. entries since these don't exist in the root
1588 * directory. We also set the offset bias to make up for having to
1589 * simulate these entries. By this I mean that at file offset 64 we
1590 * read the first entry in the root directory that lives on disk.
1591 */
1592 if (dep->de_StartCluster == MSDOSFSROOT
1593 || (FAT32(pmp) && dep->de_StartCluster == pmp->pm_rootdirblk)) {
1594#if 0
1595 printf("msdosfs_readdir(): going after . or .. in root dir, offset %d\n",
1596 offset);
1597#endif
1598 bias = 2 * sizeof(struct direntry);
1599 if (offset < bias) {
1600 for (n = (int)offset / sizeof(struct direntry);
1601 n < 2; n++) {
1602 if (FAT32(pmp))
1603 dirbuf.d_fileno = cntobn(pmp,
1604 pmp->pm_rootdirblk)
1605 * dirsperblk;
1606 else
1607 dirbuf.d_fileno = 1;
1608 dirbuf.d_type = DT_DIR;
1609 switch (n) {
1610 case 0:
1611 dirbuf.d_namlen = 1;
1612 strcpy(dirbuf.d_name, ".");
1613 break;
1614 case 1:
1615 dirbuf.d_namlen = 2;
1616 strcpy(dirbuf.d_name, "..");
1617 break;
1618 }
1619 dirbuf.d_reclen = GENERIC_DIRSIZ(&dirbuf);
1620 if (uio->uio_resid < dirbuf.d_reclen)
1621 goto out;
1622 error = uiomove((caddr_t) &dirbuf,
1623 dirbuf.d_reclen, uio);
1624 if (error)
1625 goto out;
1626 offset += sizeof(struct direntry);
1627 off = offset;
1628 if (cookies) {
1629 *cookies++ = offset;
1630 if (--ncookies <= 0)
1631 goto out;
1632 }
1633 }
1634 }
1635 }
1636
1637 off = offset;
1638 while (uio->uio_resid > 0) {
1639 lbn = de_cluster(pmp, offset - bias);
1640 on = (offset - bias) & pmp->pm_crbomask;
1641 n = min(pmp->pm_bpcluster - on, uio->uio_resid);
1642 diff = dep->de_FileSize - (offset - bias);
1643 if (diff <= 0)
1644 break;
1645 n = min(n, diff);
1646 error = pcbmap(dep, lbn, &bn, &cn, &blsize);
1647 if (error)
1648 break;
1649 error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp);
1650 if (error) {
1651 brelse(bp);
1652 return (error);
1653 }
1654 n = min(n, blsize - bp->b_resid);
1655
1656 /*
1657 * Convert from dos directory entries to fs-independent
1658 * directory entries.
1659 */
1660 for (dentp = (struct direntry *)(bp->b_data + on);
1661 (char *)dentp < bp->b_data + on + n;
1662 dentp++, offset += sizeof(struct direntry)) {
1663#if 0
1664 printf("rd: dentp %08x prev %08x crnt %08x deName %02x attr %02x\n",
1665 dentp, prev, crnt, dentp->deName[0], dentp->deAttributes);
1666#endif
1667 /*
1668 * If this is an unused entry, we can stop.
1669 */
1670 if (dentp->deName[0] == SLOT_EMPTY) {
1671 brelse(bp);
1672 goto out;
1673 }
1674 /*
1675 * Skip deleted entries.
1676 */
1677 if (dentp->deName[0] == SLOT_DELETED) {
1678 chksum = -1;
1679 continue;
1680 }
1681
1682 /*
1683 * Handle Win95 long directory entries
1684 */
1685 if (dentp->deAttributes == ATTR_WIN95) {
1686 if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME)
1687 continue;
1688 chksum = win2unixfn((struct winentry *)dentp,
1689 &dirbuf, chksum,
1690 pmp->pm_flags & MSDOSFSMNT_U2WTABLE,
1691 pmp->pm_u2w);
1692 continue;
1693 }
1694
1695 /*
1696 * Skip volume labels
1697 */
1698 if (dentp->deAttributes & ATTR_VOLUME) {
1699 chksum = -1;
1700 continue;
1701 }
1702 /*
1703 * This computation of d_fileno must match
1704 * the computation of va_fileid in
1705 * msdosfs_getattr.
1706 */
1707 if (dentp->deAttributes & ATTR_DIRECTORY) {
1708 fileno = getushort(dentp->deStartCluster);
1709 if (FAT32(pmp))
1710 fileno |= getushort(dentp->deHighClust) << 16;
1711 /* if this is the root directory */
1712 if (fileno == MSDOSFSROOT)
1713 if (FAT32(pmp))
1714 fileno = cntobn(pmp,
1715 pmp->pm_rootdirblk)
1716 * dirsperblk;
1717 else
1718 fileno = 1;
1719 else
1720 fileno = cntobn(pmp, fileno) * dirsperblk;
1721 dirbuf.d_fileno = fileno;
1722 dirbuf.d_type = DT_DIR;
1723 } else {
1724 dirbuf.d_fileno = offset / sizeof(struct direntry);
1725 dirbuf.d_type = DT_REG;
1726 }
1727 if (chksum != winChksum(dentp->deName))
1728 dirbuf.d_namlen = dos2unixfn(dentp->deName,
1729 (u_char *)dirbuf.d_name,
1730 dentp->deLowerCase |
1731 ((pmp->pm_flags & MSDOSFSMNT_SHORTNAME) ?
1732 (LCASE_BASE | LCASE_EXT) : 0),
1733 pmp->pm_flags & MSDOSFSMNT_U2WTABLE,
1734 pmp->pm_d2u,
1735 pmp->pm_flags & MSDOSFSMNT_ULTABLE,
1736 pmp->pm_ul);
1737 else
1738 dirbuf.d_name[dirbuf.d_namlen] = 0;
1739 chksum = -1;
1740 dirbuf.d_reclen = GENERIC_DIRSIZ(&dirbuf);
1741 if (uio->uio_resid < dirbuf.d_reclen) {
1742 brelse(bp);
1743 goto out;
1744 }
1745 error = uiomove((caddr_t) &dirbuf,
1746 dirbuf.d_reclen, uio);
1747 if (error) {
1748 brelse(bp);
1749 goto out;
1750 }
1751 if (cookies) {
1752 *cookies++ = offset + sizeof(struct direntry);
1753 if (--ncookies <= 0) {
1754 brelse(bp);
1755 goto out;
1756 }
1757 }
1758 off = offset + sizeof(struct direntry);
1759 }
1760 brelse(bp);
1761 }
1762out:
1763 /* Subtract unused cookies */
1764 if (ap->a_ncookies)
1765 *ap->a_ncookies -= ncookies;
1766
1767 uio->uio_offset = off;
1768
1769 /*
1770 * Set the eofflag (NFS uses it)
1771 */
1772 if (ap->a_eofflag) {
1773 if (dep->de_FileSize - (offset - bias) <= 0)
1774 *ap->a_eofflag = 1;
1775 else
1776 *ap->a_eofflag = 0;
1777 }
1778 return (error);
1779}
1780
1781/*
1782 * vp - address of vnode file the file
1783 * bn - which cluster we are interested in mapping to a filesystem block number.
1784 * vpp - returns the vnode for the block special file holding the filesystem
1785 * containing the file of interest
1786 * bnp - address of where to return the filesystem relative block number
1787 */
1788static int
1789msdosfs_bmap(ap)
1790 struct vop_bmap_args /* {
1791 struct vnode *a_vp;
1792 daddr_t a_bn;
1793 struct vnode **a_vpp;
1794 daddr_t *a_bnp;
1795 int *a_runp;
1796 int *a_runb;
1797 } */ *ap;
1798{
1799 struct denode *dep = VTODE(ap->a_vp);
1800
1801 if (ap->a_vpp != NULL)
1802 *ap->a_vpp = dep->de_devvp;
1803 if (ap->a_bnp == NULL)
1804 return (0);
1805 if (ap->a_runp) {
1806 /*
1807 * Sequential clusters should be counted here.
1808 */
1809 *ap->a_runp = 0;
1810 }
1811 if (ap->a_runb) {
1812 *ap->a_runb = 0;
1813 }
1814 return (pcbmap(dep, ap->a_bn, ap->a_bnp, 0, 0));
1815}
1816
1817static int
1818msdosfs_strategy(ap)
1819 struct vop_strategy_args /* {
1820 struct vnode *a_vp;
1821 struct buf *a_bp;
1822 } */ *ap;
1823{
1824 struct buf *bp = ap->a_bp;
1825 struct denode *dep = VTODE(bp->b_vp);
1826 struct vnode *vp;
1827 int error = 0;
1828
1829 if (bp->b_vp->v_type == VBLK || bp->b_vp->v_type == VCHR)
1830 panic("msdosfs_strategy: spec");
1831 /*
1832 * If we don't already know the filesystem relative block number
1833 * then get it using pcbmap(). If pcbmap() returns the block
1834 * number as -1 then we've got a hole in the file. DOS filesystems
1835 * don't allow files with holes, so we shouldn't ever see this.
1836 */
1837 if (bp->b_blkno == bp->b_lblkno) {
1838 error = pcbmap(dep, bp->b_lblkno, &bp->b_blkno, 0, 0);
1839 if (error) {
1840 bp->b_error = error;
1841 bp->b_ioflags |= BIO_ERROR;
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