1 /* $FreeBSD$ */ 2 /* $NetBSD: msdosfs_vfsops.c,v 1.51 1997/11/17 15:36:58 ws Exp $ */ 3 4 /*- 5 * SPDX-License-Identifier: BSD-4-Clause 6 * 7 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. 8 * Copyright (C) 1994, 1995, 1997 TooLs GmbH. 9 * All rights reserved. 10 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by TooLs GmbH. 23 * 4. The name of TooLs GmbH may not be used to endorse or promote products 24 * derived from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 29 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 31 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 32 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 33 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 34 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 35 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 */ 37 /*- 38 * Written by Paul Popelka (paulp@uts.amdahl.com) 39 * 40 * You can do anything you want with this software, just don't say you wrote 41 * it, and don't remove this notice. 42 * 43 * This software is provided "as is". 44 * 45 * The author supplies this software to be publicly redistributed on the 46 * understanding that the author is not responsible for the correct 47 * functioning of this software in any circumstances and is not liable for 48 * any damages caused by this software. 49 * 50 * October 1992 51 */ 52 53 #include <sys/param.h> 54 #include <sys/systm.h> 55 #include <sys/buf.h> 56 #include <sys/bufobj.h> 57 #include <sys/conf.h> 58 #include <sys/fcntl.h> 59 #include <sys/iconv.h> 60 #include <sys/kernel.h> 61 #include <sys/lock.h> 62 #include <sys/malloc.h> 63 #include <sys/mount.h> 64 #include <sys/mutex.h> 65 #include <sys/namei.h> 66 #include <sys/priv.h> 67 #include <sys/proc.h> 68 #include <sys/rwlock.h> 69 #include <sys/stat.h> 70 #include <sys/taskqueue.h> 71 #include <sys/vnode.h> 72 73 #include <geom/geom.h> 74 #include <geom/geom_vfs.h> 75 76 #include <fs/msdosfs/bootsect.h> 77 #include <fs/msdosfs/bpb.h> 78 #include <fs/msdosfs/direntry.h> 79 #include <fs/msdosfs/denode.h> 80 #include <fs/msdosfs/fat.h> 81 #include <fs/msdosfs/msdosfsmount.h> 82 83 #ifdef MSDOSFS_DEBUG 84 #include <sys/rwlock.h> 85 #endif 86 87 static const char msdosfs_lock_msg[] = "fatlk"; 88 89 /* Mount options that we support. */ 90 static const char *msdosfs_opts[] = { 91 "async", "noatime", "noclusterr", "noclusterw", 92 "export", "force", "from", "sync", 93 "cs_dos", "cs_local", "cs_win", "dirmask", 94 "gid", "kiconv", "longname", 95 "longnames", "mask", "shortname", "shortnames", 96 "uid", "win95", "nowin95", 97 NULL 98 }; 99 100 #if 1 /*def PC98*/ 101 /* 102 * XXX - The boot signature formatted by NEC PC-98 DOS looks like a 103 * garbage or a random value :-{ 104 * If you want to use that broken-signatured media, define the 105 * following symbol even though PC/AT. 106 * (ex. mount PC-98 DOS formatted FD on PC/AT) 107 */ 108 #define MSDOSFS_NOCHECKSIG 109 #endif 110 111 MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); 112 static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); 113 114 struct iconv_functions *msdosfs_iconv; 115 116 static int update_mp(struct mount *mp, struct thread *td); 117 static int mountmsdosfs(struct vnode *devvp, struct mount *mp); 118 static void msdosfs_remount_ro(void *arg, int pending); 119 static vfs_fhtovp_t msdosfs_fhtovp; 120 static vfs_mount_t msdosfs_mount; 121 static vfs_root_t msdosfs_root; 122 static vfs_statfs_t msdosfs_statfs; 123 static vfs_sync_t msdosfs_sync; 124 static vfs_unmount_t msdosfs_unmount; 125 126 /* Maximum length of a character set name (arbitrary). */ 127 #define MAXCSLEN 64 128 129 static int 130 update_mp(struct mount *mp, struct thread *td) 131 { 132 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 133 void *dos, *win, *local; 134 int error, v; 135 136 if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { 137 if (msdosfs_iconv != NULL) { 138 error = vfs_getopt(mp->mnt_optnew, 139 "cs_win", &win, NULL); 140 if (!error) 141 error = vfs_getopt(mp->mnt_optnew, 142 "cs_local", &local, NULL); 143 if (!error) 144 error = vfs_getopt(mp->mnt_optnew, 145 "cs_dos", &dos, NULL); 146 if (!error) { 147 msdosfs_iconv->open(win, local, &pmp->pm_u2w); 148 msdosfs_iconv->open(local, win, &pmp->pm_w2u); 149 msdosfs_iconv->open(dos, local, &pmp->pm_u2d); 150 msdosfs_iconv->open(local, dos, &pmp->pm_d2u); 151 } 152 if (error != 0) 153 return (error); 154 } else { 155 pmp->pm_w2u = NULL; 156 pmp->pm_u2w = NULL; 157 pmp->pm_d2u = NULL; 158 pmp->pm_u2d = NULL; 159 } 160 } 161 162 if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1) 163 pmp->pm_gid = v; 164 if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1) 165 pmp->pm_uid = v; 166 if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1) 167 pmp->pm_mask = v & ALLPERMS; 168 if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1) 169 pmp->pm_dirmask = v & ALLPERMS; 170 vfs_flagopt(mp->mnt_optnew, "shortname", 171 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 172 vfs_flagopt(mp->mnt_optnew, "shortnames", 173 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 174 vfs_flagopt(mp->mnt_optnew, "longname", 175 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 176 vfs_flagopt(mp->mnt_optnew, "longnames", 177 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 178 vfs_flagopt(mp->mnt_optnew, "kiconv", 179 &pmp->pm_flags, MSDOSFSMNT_KICONV); 180 181 if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) 182 pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 183 else 184 pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; 185 186 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 187 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 188 else 189 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 190 return 0; 191 } 192 193 static int 194 msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags) 195 { 196 struct msdosfs_args args; 197 int error; 198 199 if (data == NULL) 200 return (EINVAL); 201 error = copyin(data, &args, sizeof args); 202 if (error) 203 return (error); 204 205 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 206 ma = mount_arg(ma, "export", &args.export, sizeof(args.export)); 207 ma = mount_argf(ma, "uid", "%d", args.uid); 208 ma = mount_argf(ma, "gid", "%d", args.gid); 209 ma = mount_argf(ma, "mask", "%d", args.mask); 210 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 211 212 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 213 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 214 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 215 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 216 217 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 218 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 219 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 220 221 error = kernel_mount(ma, flags); 222 223 return (error); 224 } 225 226 /* 227 * mp - path - addr in user space of mount point (ie /usr or whatever) 228 * data - addr in user space of mount params including the name of the block 229 * special file to treat as a filesystem. 230 */ 231 static int 232 msdosfs_mount(struct mount *mp) 233 { 234 struct vnode *devvp, *odevvp; /* vnode for blk device to mount */ 235 struct thread *td; 236 /* msdosfs specific mount control block */ 237 struct msdosfsmount *pmp = NULL; 238 struct nameidata ndp; 239 int error, flags; 240 accmode_t accmode; 241 char *from; 242 243 td = curthread; 244 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 245 return (EINVAL); 246 247 /* 248 * If updating, check whether changing from read-only to 249 * read/write; if there is no device name, that's all we do. 250 */ 251 if (mp->mnt_flag & MNT_UPDATE) { 252 pmp = VFSTOMSDOSFS(mp); 253 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 254 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 255 if ((error = vn_start_write(NULL, &mp, V_WAIT)) != 0) 256 return (error); 257 error = vfs_write_suspend_umnt(mp); 258 if (error != 0) 259 return (error); 260 261 flags = WRITECLOSE; 262 if (mp->mnt_flag & MNT_FORCE) 263 flags |= FORCECLOSE; 264 error = vflush(mp, 0, flags, td); 265 if (error != 0) { 266 vfs_write_resume(mp, 0); 267 return (error); 268 } 269 270 /* 271 * Now the volume is clean. Mark it so while the 272 * device is still rw. 273 */ 274 error = markvoldirty(pmp, 0); 275 if (error != 0) { 276 vfs_write_resume(mp, 0); 277 (void)markvoldirty(pmp, 1); 278 return (error); 279 } 280 281 /* Downgrade the device from rw to ro. */ 282 g_topology_lock(); 283 error = g_access(pmp->pm_cp, 0, -1, 0); 284 g_topology_unlock(); 285 if (error) { 286 vfs_write_resume(mp, 0); 287 (void)markvoldirty(pmp, 1); 288 return (error); 289 } 290 291 /* 292 * Backing out after an error was painful in the 293 * above. Now we are committed to succeeding. 294 */ 295 pmp->pm_fmod = 0; 296 pmp->pm_flags |= MSDOSFSMNT_RONLY; 297 MNT_ILOCK(mp); 298 mp->mnt_flag |= MNT_RDONLY; 299 MNT_IUNLOCK(mp); 300 vfs_write_resume(mp, 0); 301 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 302 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 303 /* 304 * If upgrade to read-write by non-root, then verify 305 * that user has necessary permissions on the device. 306 */ 307 odevvp = pmp->pm_odevvp; 308 vn_lock(odevvp, LK_EXCLUSIVE | LK_RETRY); 309 error = VOP_ACCESS(odevvp, VREAD | VWRITE, 310 td->td_ucred, td); 311 if (error) 312 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 313 if (error) { 314 VOP_UNLOCK(odevvp); 315 return (error); 316 } 317 VOP_UNLOCK(odevvp); 318 g_topology_lock(); 319 error = g_access(pmp->pm_cp, 0, 1, 0); 320 g_topology_unlock(); 321 if (error) 322 return (error); 323 324 /* Now that the volume is modifiable, mark it dirty. */ 325 error = markvoldirty_upgrade(pmp, true, true); 326 if (error) { 327 /* 328 * If dirtying the superblock failed, drop GEOM 329 * 'w' refs (we're still RO). 330 */ 331 g_topology_lock(); 332 (void)g_access(pmp->pm_cp, 0, -1, 0); 333 g_topology_unlock(); 334 335 return (error); 336 } 337 338 pmp->pm_fmod = 1; 339 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 340 MNT_ILOCK(mp); 341 mp->mnt_flag &= ~MNT_RDONLY; 342 MNT_IUNLOCK(mp); 343 } 344 345 /* 346 * Avoid namei() below. The "from" option is not set. 347 * Update of the devvp is pointless for this case. 348 */ 349 if ((pmp->pm_flags & MSDOSFS_ERR_RO) != 0) 350 return (0); 351 } 352 /* 353 * Not an update, or updating the name: look up the name 354 * and verify that it refers to a sensible disk device. 355 */ 356 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 357 return (EINVAL); 358 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from); 359 error = namei(&ndp); 360 if (error) 361 return (error); 362 devvp = ndp.ni_vp; 363 NDFREE_PNBUF(&ndp); 364 365 if (!vn_isdisk_error(devvp, &error)) { 366 vput(devvp); 367 return (error); 368 } 369 /* 370 * If mount by non-root, then verify that user has necessary 371 * permissions on the device. 372 */ 373 accmode = VREAD; 374 if ((mp->mnt_flag & MNT_RDONLY) == 0) 375 accmode |= VWRITE; 376 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 377 if (error) 378 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 379 if (error) { 380 vput(devvp); 381 return (error); 382 } 383 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 384 error = mountmsdosfs(devvp, mp); 385 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 386 pmp = VFSTOMSDOSFS(mp); 387 #endif 388 } else { 389 vput(devvp); 390 if (devvp != pmp->pm_odevvp) 391 return (EINVAL); /* XXX needs translation */ 392 } 393 if (error) { 394 vrele(devvp); 395 return (error); 396 } 397 398 error = update_mp(mp, td); 399 if (error) { 400 if ((mp->mnt_flag & MNT_UPDATE) == 0) 401 msdosfs_unmount(mp, MNT_FORCE); 402 return error; 403 } 404 405 vfs_mountedfrom(mp, from); 406 #ifdef MSDOSFS_DEBUG 407 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 408 #endif 409 return (0); 410 } 411 412 static int 413 mountmsdosfs(struct vnode *odevvp, struct mount *mp) 414 { 415 struct msdosfsmount *pmp; 416 struct buf *bp; 417 struct cdev *dev; 418 struct vnode *devvp; 419 union bootsector *bsp; 420 struct byte_bpb33 *b33; 421 struct byte_bpb50 *b50; 422 struct byte_bpb710 *b710; 423 uint8_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 devvp = mntfs_allocvp(mp, odevvp); 434 VOP_UNLOCK(odevvp); 435 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 436 dev = devvp->v_rdev; 437 if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0, 438 (uintptr_t)mp) == 0) { 439 mntfs_freevp(devvp); 440 return (EBUSY); 441 } 442 g_topology_lock(); 443 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 444 g_topology_unlock(); 445 if (error != 0) { 446 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 447 mntfs_freevp(devvp); 448 return (error); 449 } 450 dev_ref(dev); 451 bo = &devvp->v_bufobj; 452 BO_LOCK(&odevvp->v_bufobj); 453 odevvp->v_bufobj.bo_flag |= BO_NOBUFS; 454 BO_UNLOCK(&odevvp->v_bufobj); 455 VOP_UNLOCK(devvp); 456 if (dev->si_iosize_max != 0) 457 mp->mnt_iosize_max = dev->si_iosize_max; 458 if (mp->mnt_iosize_max > maxphys) 459 mp->mnt_iosize_max = maxphys; 460 461 /* 462 * Read the boot sector of the filesystem, and then check the 463 * boot signature. If not a dos boot sector then error out. 464 * 465 * NOTE: 8192 is a magic size that works for ffs. 466 */ 467 error = bread(devvp, 0, 8192, NOCRED, &bp); 468 if (error) 469 goto error_exit; 470 bp->b_flags |= B_AGE; 471 bsp = (union bootsector *)bp->b_data; 472 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 473 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 474 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 475 476 #ifndef MSDOSFS_NOCHECKSIG 477 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 || 478 bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 479 error = EINVAL; 480 goto error_exit; 481 } 482 #endif 483 484 pmp = malloc(sizeof(*pmp), M_MSDOSFSMNT, M_WAITOK | M_ZERO); 485 pmp->pm_mountp = mp; 486 pmp->pm_cp = cp; 487 pmp->pm_bo = bo; 488 489 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); 490 lockinit(&pmp->pm_checkpath_lock, 0, "msdoscp", 0, 0); 491 492 TASK_INIT(&pmp->pm_rw2ro_task, 0, msdosfs_remount_ro, pmp); 493 494 /* 495 * Initialize ownerships and permissions, since nothing else will 496 * initialize them iff we are mounting root. 497 */ 498 pmp->pm_uid = UID_ROOT; 499 pmp->pm_gid = GID_WHEEL; 500 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 501 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 502 503 /* 504 * Compute several useful quantities from the bpb in the 505 * bootsector. Copy in the dos 5 variant of the bpb then fix up 506 * the fields that are different between dos 5 and dos 3.3. 507 */ 508 SecPerClust = b50->bpbSecPerClust; 509 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 510 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 511 error = EINVAL; 512 goto error_exit; 513 } 514 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 515 pmp->pm_FATs = b50->bpbFATs; 516 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 517 pmp->pm_Sectors = getushort(b50->bpbSectors); 518 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 519 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 520 pmp->pm_Heads = getushort(b50->bpbHeads); 521 pmp->pm_Media = b50->bpbMedia; 522 523 /* calculate the ratio of sector size to DEV_BSIZE */ 524 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 525 526 /* 527 * We don't check pm_Heads nor pm_SecPerTrack, because 528 * these may not be set for EFI file systems. We don't 529 * use these anyway, so we're unaffected if they are 530 * invalid. 531 */ 532 if (pmp->pm_BytesPerSec == 0 || SecPerClust == 0) { 533 error = EINVAL; 534 goto error_exit; 535 } 536 537 if (pmp->pm_Sectors == 0) { 538 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 539 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 540 } else { 541 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 542 pmp->pm_HugeSectors = pmp->pm_Sectors; 543 } 544 545 if (pmp->pm_RootDirEnts == 0) { 546 if (pmp->pm_FATsecs != 0 || getushort(b710->bpbFSVers) != 0) { 547 error = EINVAL; 548 #ifdef MSDOSFS_DEBUG 549 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 550 #endif 551 goto error_exit; 552 } 553 pmp->pm_fatmask = FAT32_MASK; 554 pmp->pm_fatmult = 4; 555 pmp->pm_fatdiv = 1; 556 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 557 if ((getushort(b710->bpbExtFlags) & FATMIRROR) != 0) 558 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 559 else 560 pmp->pm_flags |= MSDOSFS_FATMIRROR; 561 } else 562 pmp->pm_flags |= MSDOSFS_FATMIRROR; 563 564 /* 565 * Check a few values (could do some more): 566 * - logical sector size: power of 2, >= block size 567 * - sectors per cluster: power of 2, >= 1 568 * - number of sectors: >= 1, <= size of partition 569 * - number of FAT sectors: >= 1 570 */ 571 if (SecPerClust == 0 || (SecPerClust & (SecPerClust - 1)) != 0 || 572 pmp->pm_BytesPerSec < DEV_BSIZE || 573 (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) != 0 || 574 pmp->pm_HugeSectors == 0 || pmp->pm_FATsecs == 0 || 575 SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) { 576 error = EINVAL; 577 goto error_exit; 578 } 579 580 if ((off_t)pmp->pm_HugeSectors * pmp->pm_BytesPerSec < 581 pmp->pm_HugeSectors /* overflow */ || 582 (off_t)pmp->pm_HugeSectors * pmp->pm_BytesPerSec > 583 cp->provider->mediasize /* past end of vol */) { 584 error = EINVAL; 585 goto error_exit; 586 } 587 588 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 589 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 590 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 591 SecPerClust *= pmp->pm_BlkPerSec; 592 593 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 594 595 if (FAT32(pmp)) { 596 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 597 pmp->pm_firstcluster = pmp->pm_fatblk + 598 pmp->pm_FATs * pmp->pm_FATsecs; 599 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 600 } else { 601 pmp->pm_rootdirblk = pmp->pm_fatblk + 602 pmp->pm_FATs * pmp->pm_FATsecs; 603 pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts * 604 sizeof(struct direntry), DEV_BSIZE); /* in blocks */ 605 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 606 } 607 608 if (pmp->pm_HugeSectors <= pmp->pm_firstcluster) { 609 error = EINVAL; 610 goto error_exit; 611 } 612 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 613 SecPerClust + 1; 614 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 615 616 if (pmp->pm_fatmask == 0) { 617 if (pmp->pm_maxcluster <= ((CLUST_RSRVD - CLUST_FIRST) & 618 FAT12_MASK)) { 619 /* 620 * This will usually be a floppy disk. This size makes 621 * sure that one FAT entry will not be split across 622 * multiple blocks. 623 */ 624 pmp->pm_fatmask = FAT12_MASK; 625 pmp->pm_fatmult = 3; 626 pmp->pm_fatdiv = 2; 627 } else { 628 pmp->pm_fatmask = FAT16_MASK; 629 pmp->pm_fatmult = 2; 630 pmp->pm_fatdiv = 1; 631 } 632 } 633 634 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 635 if (pmp->pm_maxcluster >= clusters) { 636 #ifdef MSDOSFS_DEBUG 637 printf("Warning: number of clusters (%ld) exceeds FAT " 638 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 639 #endif 640 pmp->pm_maxcluster = clusters - 1; 641 } 642 643 if (FAT12(pmp)) 644 pmp->pm_fatblocksize = 3 * 512; 645 else 646 pmp->pm_fatblocksize = PAGE_SIZE; 647 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 648 pmp->pm_BytesPerSec); 649 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 650 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 651 652 /* 653 * Compute mask and shift value for isolating cluster relative byte 654 * offsets and cluster numbers from a file offset. 655 */ 656 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 657 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 658 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 659 660 /* 661 * Check for valid cluster size 662 * must be a power of 2 663 */ 664 if ((pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) != 0) { 665 error = EINVAL; 666 goto error_exit; 667 } 668 669 /* 670 * Release the bootsector buffer. 671 */ 672 brelse(bp); 673 bp = NULL; 674 675 /* 676 * Check the fsinfo sector if we have one. Silently fix up our 677 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 678 * or too large. Ignore fp->fsinfree for now, since we need to 679 * read the entire FAT anyway to fill the inuse map. 680 */ 681 if (pmp->pm_fsinfo) { 682 struct fsinfo *fp; 683 684 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 685 NOCRED, &bp)) != 0) 686 goto error_exit; 687 fp = (struct fsinfo *)bp->b_data; 688 if (!bcmp(fp->fsisig1, "RRaA", 4) && 689 !bcmp(fp->fsisig2, "rrAa", 4) && 690 !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 691 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 692 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 693 pmp->pm_nxtfree = CLUST_FIRST; 694 } else 695 pmp->pm_fsinfo = 0; 696 brelse(bp); 697 bp = NULL; 698 } 699 700 /* 701 * Finish initializing pmp->pm_nxtfree (just in case the first few 702 * sectors aren't properly reserved in the FAT). This completes 703 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 704 * value if there is no fsinfo. We will use pmp->pm_nxtfree 705 * internally even if there is no fsinfo. 706 */ 707 if (pmp->pm_nxtfree < CLUST_FIRST) 708 pmp->pm_nxtfree = CLUST_FIRST; 709 710 /* 711 * Allocate memory for the bitmap of allocated clusters, and then 712 * fill it in. 713 */ 714 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, 715 N_INUSEBITS) * sizeof(*pmp->pm_inusemap), M_MSDOSFSFAT, M_WAITOK); 716 717 /* 718 * fillinusemap() needs pm_devvp. 719 */ 720 pmp->pm_devvp = devvp; 721 pmp->pm_odevvp = odevvp; 722 pmp->pm_dev = dev; 723 724 /* 725 * Have the inuse map filled in. 726 */ 727 MSDOSFS_LOCK_MP(pmp); 728 error = fillinusemap(pmp); 729 MSDOSFS_UNLOCK_MP(pmp); 730 if (error != 0) 731 goto error_exit; 732 733 /* 734 * If they want FAT updates to be synchronous then let them suffer 735 * the performance degradation in exchange for the on disk copy of 736 * the FAT being correct just about all the time. I suppose this 737 * would be a good thing to turn on if the kernel is still flakey. 738 */ 739 if (mp->mnt_flag & MNT_SYNCHRONOUS) 740 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 741 742 /* 743 * Finish up. 744 */ 745 if (ronly) 746 pmp->pm_flags |= MSDOSFSMNT_RONLY; 747 else { 748 if ((error = markvoldirty(pmp, 1)) != 0) 749 goto error_exit; 750 pmp->pm_fmod = 1; 751 } 752 mp->mnt_data = pmp; 753 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 754 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 755 MNT_ILOCK(mp); 756 mp->mnt_flag |= MNT_LOCAL; 757 mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF; 758 MNT_IUNLOCK(mp); 759 760 return (0); 761 762 error_exit: 763 if (bp != NULL) 764 brelse(bp); 765 if (cp != NULL) { 766 g_topology_lock(); 767 g_vfs_close(cp); 768 g_topology_unlock(); 769 } 770 if (pmp != NULL) { 771 lockdestroy(&pmp->pm_fatlock); 772 lockdestroy(&pmp->pm_checkpath_lock); 773 free(pmp->pm_inusemap, M_MSDOSFSFAT); 774 free(pmp, M_MSDOSFSMNT); 775 mp->mnt_data = NULL; 776 } 777 BO_LOCK(&odevvp->v_bufobj); 778 odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS; 779 BO_UNLOCK(&odevvp->v_bufobj); 780 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 781 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 782 mntfs_freevp(devvp); 783 dev_rel(dev); 784 return (error); 785 } 786 787 /* 788 * Unmount the filesystem described by mp. 789 */ 790 static int 791 msdosfs_unmount(struct mount *mp, int mntflags) 792 { 793 struct msdosfsmount *pmp; 794 int error, flags; 795 bool susp; 796 797 error = flags = 0; 798 pmp = VFSTOMSDOSFS(mp); 799 susp = (pmp->pm_flags & MSDOSFSMNT_RONLY) == 0; 800 801 if (susp) { 802 error = vfs_write_suspend_umnt(mp); 803 if (error != 0) 804 return (error); 805 } 806 807 if ((mntflags & MNT_FORCE) != 0) 808 flags |= FORCECLOSE; 809 error = vflush(mp, 0, flags, curthread); 810 if (error != 0 && error != ENXIO) { 811 if (susp) 812 vfs_write_resume(mp, VR_START_WRITE); 813 return (error); 814 } 815 if (susp) { 816 error = markvoldirty(pmp, 0); 817 if (error != 0 && error != ENXIO) { 818 if (susp) 819 vfs_write_resume(mp, VR_START_WRITE); 820 (void)markvoldirty(pmp, 1); 821 return (error); 822 } 823 } 824 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 825 if (pmp->pm_w2u) 826 msdosfs_iconv->close(pmp->pm_w2u); 827 if (pmp->pm_u2w) 828 msdosfs_iconv->close(pmp->pm_u2w); 829 if (pmp->pm_d2u) 830 msdosfs_iconv->close(pmp->pm_d2u); 831 if (pmp->pm_u2d) 832 msdosfs_iconv->close(pmp->pm_u2d); 833 } 834 835 #ifdef MSDOSFS_DEBUG 836 { 837 struct vnode *vp = pmp->pm_devvp; 838 struct bufobj *bo; 839 840 bo = &vp->v_bufobj; 841 BO_LOCK(bo); 842 VI_LOCK(vp); 843 vn_printf(vp, 844 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 845 printf("freef %p, freeb %p, mount %p\n", 846 TAILQ_NEXT(vp, v_vnodelist), vp->v_vnodelist.tqe_prev, 847 vp->v_mount); 848 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %d, type %d\n", 849 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 850 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 851 vp->v_bufobj.bo_numoutput, vp->v_type); 852 VI_UNLOCK(vp); 853 BO_UNLOCK(bo); 854 } 855 #endif 856 if (susp) 857 vfs_write_resume(mp, VR_START_WRITE); 858 859 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 860 g_topology_lock(); 861 g_vfs_close(pmp->pm_cp); 862 g_topology_unlock(); 863 BO_LOCK(&pmp->pm_odevvp->v_bufobj); 864 pmp->pm_odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS; 865 BO_UNLOCK(&pmp->pm_odevvp->v_bufobj); 866 atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0); 867 mntfs_freevp(pmp->pm_devvp); 868 vrele(pmp->pm_odevvp); 869 dev_rel(pmp->pm_dev); 870 free(pmp->pm_inusemap, M_MSDOSFSFAT); 871 lockdestroy(&pmp->pm_fatlock); 872 lockdestroy(&pmp->pm_checkpath_lock); 873 free(pmp, M_MSDOSFSMNT); 874 mp->mnt_data = NULL; 875 MNT_ILOCK(mp); 876 mp->mnt_flag &= ~MNT_LOCAL; 877 MNT_IUNLOCK(mp); 878 return (error); 879 } 880 881 static void 882 msdosfs_remount_ro(void *arg, int pending) 883 { 884 struct msdosfsmount *pmp; 885 int error; 886 887 pmp = arg; 888 889 MSDOSFS_LOCK_MP(pmp); 890 if ((pmp->pm_flags & MSDOSFS_ERR_RO) != 0) { 891 while ((pmp->pm_flags & MSDOSFS_ERR_RO) != 0) 892 msleep(&pmp->pm_flags, &pmp->pm_fatlock, PVFS, 893 "msdoserrro", hz); 894 } else if ((pmp->pm_mountp->mnt_flag & MNT_RDONLY) == 0) { 895 pmp->pm_flags |= MSDOSFS_ERR_RO; 896 MSDOSFS_UNLOCK_MP(pmp); 897 printf("%s: remounting read-only due to corruption\n", 898 pmp->pm_mountp->mnt_stat.f_mntfromname); 899 error = vfs_remount_ro(pmp->pm_mountp); 900 if (error != 0) 901 printf("%s: remounting read-only failed: error %d\n", 902 pmp->pm_mountp->mnt_stat.f_mntfromname, error); 903 else 904 printf("remounted %s read-only\n", 905 pmp->pm_mountp->mnt_stat.f_mntfromname); 906 MSDOSFS_LOCK_MP(pmp); 907 pmp->pm_flags &= ~MSDOSFS_ERR_RO; 908 wakeup(&pmp->pm_flags); 909 } 910 MSDOSFS_UNLOCK_MP(pmp); 911 912 vfs_unbusy(pmp->pm_mountp); 913 } 914 915 void 916 msdosfs_integrity_error(struct msdosfsmount *pmp) 917 { 918 int error; 919 920 error = vfs_busy(pmp->pm_mountp, MBF_NOWAIT); 921 if (error == 0) 922 taskqueue_enqueue(taskqueue_thread, &pmp->pm_rw2ro_task); 923 else 924 printf("%s: integrity error busying failed, error %d\n", 925 pmp->pm_mountp->mnt_stat.f_mntfromname, error); 926 } 927 928 static int 929 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 930 { 931 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 932 struct denode *ndep; 933 int error; 934 935 #ifdef MSDOSFS_DEBUG 936 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 937 #endif 938 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, LK_EXCLUSIVE, &ndep); 939 if (error) 940 return (error); 941 *vpp = DETOV(ndep); 942 return (0); 943 } 944 945 static int 946 msdosfs_statfs(struct mount *mp, struct statfs *sbp) 947 { 948 struct msdosfsmount *pmp; 949 950 pmp = VFSTOMSDOSFS(mp); 951 sbp->f_bsize = pmp->pm_bpcluster; 952 sbp->f_iosize = pmp->pm_bpcluster; 953 sbp->f_blocks = pmp->pm_maxcluster + 1; 954 sbp->f_bfree = pmp->pm_freeclustercount; 955 sbp->f_bavail = pmp->pm_freeclustercount; 956 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 957 sbp->f_ffree = 0; /* what to put in here? */ 958 return (0); 959 } 960 961 /* 962 * If we have an FSInfo block, update it. 963 */ 964 static int 965 msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) 966 { 967 struct fsinfo *fp; 968 struct buf *bp; 969 int error; 970 971 MSDOSFS_LOCK_MP(pmp); 972 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { 973 error = 0; 974 goto unlock; 975 } 976 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 977 NOCRED, &bp); 978 if (error != 0) { 979 goto unlock; 980 } 981 fp = (struct fsinfo *)bp->b_data; 982 putulong(fp->fsinfree, pmp->pm_freeclustercount); 983 putulong(fp->fsinxtfree, pmp->pm_nxtfree); 984 pmp->pm_flags &= ~MSDOSFS_FSIMOD; 985 if (waitfor == MNT_WAIT) 986 error = bwrite(bp); 987 else 988 bawrite(bp); 989 unlock: 990 MSDOSFS_UNLOCK_MP(pmp); 991 return (error); 992 } 993 994 static int 995 msdosfs_sync(struct mount *mp, int waitfor) 996 { 997 struct vnode *vp, *nvp; 998 struct thread *td; 999 struct denode *dep; 1000 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 1001 int error, allerror = 0; 1002 1003 td = curthread; 1004 1005 /* 1006 * If we ever switch to not updating all of the FATs all the time, 1007 * this would be the place to update them from the first one. 1008 */ 1009 if (pmp->pm_fmod != 0) { 1010 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 1011 panic("msdosfs_sync: rofs mod"); 1012 else { 1013 /* update FATs here */ 1014 } 1015 } 1016 /* 1017 * Write back each (modified) denode. 1018 */ 1019 loop: 1020 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { 1021 if (vp->v_type == VNON) { 1022 VI_UNLOCK(vp); 1023 continue; 1024 } 1025 dep = VTODE(vp); 1026 if ((dep->de_flag & 1027 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 1028 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 1029 waitfor == MNT_LAZY)) { 1030 VI_UNLOCK(vp); 1031 continue; 1032 } 1033 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK); 1034 if (error) { 1035 if (error == ENOENT) { 1036 MNT_VNODE_FOREACH_ALL_ABORT(mp, nvp); 1037 goto loop; 1038 } 1039 continue; 1040 } 1041 error = VOP_FSYNC(vp, waitfor, td); 1042 if (error) 1043 allerror = error; 1044 VOP_UNLOCK(vp); 1045 vrele(vp); 1046 } 1047 1048 /* 1049 * Flush filesystem control info. 1050 */ 1051 if (waitfor != MNT_LAZY) { 1052 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 1053 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 1054 if (error) 1055 allerror = error; 1056 VOP_UNLOCK(pmp->pm_devvp); 1057 } 1058 1059 error = msdosfs_fsiflush(pmp, waitfor); 1060 if (error != 0) 1061 allerror = error; 1062 1063 if (allerror == 0 && waitfor == MNT_SUSPEND) { 1064 MNT_ILOCK(mp); 1065 mp->mnt_kern_flag |= MNTK_SUSPEND2 | MNTK_SUSPENDED; 1066 MNT_IUNLOCK(mp); 1067 } 1068 return (allerror); 1069 } 1070 1071 static int 1072 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) 1073 { 1074 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 1075 struct defid *defhp = (struct defid *) fhp; 1076 struct denode *dep; 1077 int error; 1078 1079 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, 1080 LK_EXCLUSIVE, &dep); 1081 if (error) { 1082 *vpp = NULLVP; 1083 return (error); 1084 } 1085 *vpp = DETOV(dep); 1086 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 1087 return (0); 1088 } 1089 1090 static struct vfsops msdosfs_vfsops = { 1091 .vfs_fhtovp = msdosfs_fhtovp, 1092 .vfs_mount = msdosfs_mount, 1093 .vfs_cmount = msdosfs_cmount, 1094 .vfs_root = msdosfs_root, 1095 .vfs_statfs = msdosfs_statfs, 1096 .vfs_sync = msdosfs_sync, 1097 .vfs_unmount = msdosfs_unmount, 1098 }; 1099 1100 VFS_SET(msdosfs_vfsops, msdosfs, 0); 1101 MODULE_VERSION(msdosfs, 1); 1102