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sys/fs/msdosfs/msdosfs_vfsops.c
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1 /* $FreeBSD: releng/11.0/sys/fs/msdosfs/msdosfs_vfsops.c 300371 2016-05-21 11:40:41Z 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 g_topology_lock(); 296 error = g_access(pmp->pm_cp, 0, -1, 0); 297 g_topology_unlock(); 298 if (error) { 299 (void)markvoldirty(pmp, 1); 300 return (error); 301 } 302 303 /* 304 * Backing out after an error was painful in the 305 * above. Now we are committed to succeeding. 306 */ 307 pmp->pm_fmod = 0; 308 pmp->pm_flags |= MSDOSFSMNT_RONLY; 309 MNT_ILOCK(mp); 310 mp->mnt_flag |= MNT_RDONLY; 311 MNT_IUNLOCK(mp); 312 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 313 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 314 /* 315 * If upgrade to read-write by non-root, then verify 316 * that user has necessary permissions on the device. 317 */ 318 devvp = pmp->pm_devvp; 319 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 320 error = VOP_ACCESS(devvp, VREAD | VWRITE, 321 td->td_ucred, td); 322 if (error) 323 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 324 if (error) { 325 VOP_UNLOCK(devvp, 0); 326 return (error); 327 } 328 VOP_UNLOCK(devvp, 0); 329 g_topology_lock(); 330 error = g_access(pmp->pm_cp, 0, 1, 0); 331 g_topology_unlock(); 332 if (error) 333 return (error); 334 335 pmp->pm_fmod = 1; 336 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 337 MNT_ILOCK(mp); 338 mp->mnt_flag &= ~MNT_RDONLY; 339 MNT_IUNLOCK(mp); 340 341 /* Now that the volume is modifiable, mark it dirty. */ 342 error = markvoldirty(pmp, 1); 343 if (error) 344 return (error); 345 } 346 } 347 /* 348 * Not an update, or updating the name: look up the name 349 * and verify that it refers to a sensible disk device. 350 */ 351 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 352 return (EINVAL); 353 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 354 error = namei(&ndp); 355 if (error) 356 return (error); 357 devvp = ndp.ni_vp; 358 NDFREE(&ndp, NDF_ONLY_PNBUF); 359 360 if (!vn_isdisk(devvp, &error)) { 361 vput(devvp); 362 return (error); 363 } 364 /* 365 * If mount by non-root, then verify that user has necessary 366 * permissions on the device. 367 */ 368 accmode = VREAD; 369 if ((mp->mnt_flag & MNT_RDONLY) == 0) 370 accmode |= VWRITE; 371 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 372 if (error) 373 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 374 if (error) { 375 vput(devvp); 376 return (error); 377 } 378 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 379 error = mountmsdosfs(devvp, mp); 380 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 381 pmp = VFSTOMSDOSFS(mp); 382 #endif 383 } else { 384 vput(devvp); 385 if (devvp != pmp->pm_devvp) 386 return (EINVAL); /* XXX needs translation */ 387 } 388 if (error) { 389 vrele(devvp); 390 return (error); 391 } 392 393 error = update_mp(mp, td); 394 if (error) { 395 if ((mp->mnt_flag & MNT_UPDATE) == 0) 396 msdosfs_unmount(mp, MNT_FORCE); 397 return error; 398 } 399 400 vfs_mountedfrom(mp, from); 401 #ifdef MSDOSFS_DEBUG 402 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 403 #endif 404 return (0); 405 } 406 407 static int 408 mountmsdosfs(struct vnode *devvp, struct mount *mp) 409 { 410 struct msdosfsmount *pmp; 411 struct buf *bp; 412 struct cdev *dev; 413 union bootsector *bsp; 414 struct byte_bpb33 *b33; 415 struct byte_bpb50 *b50; 416 struct byte_bpb710 *b710; 417 u_int8_t SecPerClust; 418 u_long clusters; 419 int ronly, error; 420 struct g_consumer *cp; 421 struct bufobj *bo; 422 423 bp = NULL; /* This and pmp both used in error_exit. */ 424 pmp = NULL; 425 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 426 427 dev = devvp->v_rdev; 428 if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0, 429 (uintptr_t)mp) == 0) { 430 VOP_UNLOCK(devvp, 0); 431 return (EBUSY); 432 } 433 g_topology_lock(); 434 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 435 g_topology_unlock(); 436 if (error != 0) { 437 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 438 VOP_UNLOCK(devvp, 0); 439 return (error); 440 } 441 dev_ref(dev); 442 VOP_UNLOCK(devvp, 0); 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 = howmany(pmp->pm_RootDirEnts * 610 sizeof(struct direntry), DEV_BSIZE); /* in blocks */ 611 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 612 } 613 614 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 615 SecPerClust + 1; 616 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 617 618 if (pmp->pm_fatmask == 0) { 619 if (pmp->pm_maxcluster 620 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 621 /* 622 * This will usually be a floppy disk. This size makes 623 * sure that one fat entry will not be split across 624 * multiple blocks. 625 */ 626 pmp->pm_fatmask = FAT12_MASK; 627 pmp->pm_fatmult = 3; 628 pmp->pm_fatdiv = 2; 629 } else { 630 pmp->pm_fatmask = FAT16_MASK; 631 pmp->pm_fatmult = 2; 632 pmp->pm_fatdiv = 1; 633 } 634 } 635 636 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 637 if (pmp->pm_maxcluster >= clusters) { 638 #ifdef MSDOSFS_DEBUG 639 printf("Warning: number of clusters (%ld) exceeds FAT " 640 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 641 #endif 642 pmp->pm_maxcluster = clusters - 1; 643 } 644 645 if (FAT12(pmp)) 646 pmp->pm_fatblocksize = 3 * 512; 647 else 648 pmp->pm_fatblocksize = PAGE_SIZE; 649 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 650 pmp->pm_BytesPerSec); 651 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 652 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 653 654 /* 655 * Compute mask and shift value for isolating cluster relative byte 656 * offsets and cluster numbers from a file offset. 657 */ 658 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 659 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 660 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 661 662 /* 663 * Check for valid cluster size 664 * must be a power of 2 665 */ 666 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 667 error = EINVAL; 668 goto error_exit; 669 } 670 671 /* 672 * Release the bootsector buffer. 673 */ 674 brelse(bp); 675 bp = NULL; 676 677 /* 678 * Check the fsinfo sector if we have one. Silently fix up our 679 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 680 * or too large. Ignore fp->fsinfree for now, since we need to 681 * read the entire FAT anyway to fill the inuse map. 682 */ 683 if (pmp->pm_fsinfo) { 684 struct fsinfo *fp; 685 686 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 687 NOCRED, &bp)) != 0) 688 goto error_exit; 689 fp = (struct fsinfo *)bp->b_data; 690 if (!bcmp(fp->fsisig1, "RRaA", 4) 691 && !bcmp(fp->fsisig2, "rrAa", 4) 692 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 693 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 694 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 695 pmp->pm_nxtfree = CLUST_FIRST; 696 } else 697 pmp->pm_fsinfo = 0; 698 brelse(bp); 699 bp = NULL; 700 } 701 702 /* 703 * Finish initializing pmp->pm_nxtfree (just in case the first few 704 * sectors aren't properly reserved in the FAT). This completes 705 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 706 * value if there is no fsinfo. We will use pmp->pm_nxtfree 707 * internally even if there is no fsinfo. 708 */ 709 if (pmp->pm_nxtfree < CLUST_FIRST) 710 pmp->pm_nxtfree = CLUST_FIRST; 711 712 /* 713 * Allocate memory for the bitmap of allocated clusters, and then 714 * fill it in. 715 */ 716 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 717 * sizeof(*pmp->pm_inusemap), 718 M_MSDOSFSFAT, M_WAITOK); 719 720 /* 721 * fillinusemap() needs pm_devvp. 722 */ 723 pmp->pm_devvp = devvp; 724 pmp->pm_dev = dev; 725 726 /* 727 * Have the inuse map filled in. 728 */ 729 MSDOSFS_LOCK_MP(pmp); 730 error = fillinusemap(pmp); 731 MSDOSFS_UNLOCK_MP(pmp); 732 if (error != 0) 733 goto error_exit; 734 735 /* 736 * If they want fat updates to be synchronous then let them suffer 737 * the performance degradation in exchange for the on disk copy of 738 * the fat being correct just about all the time. I suppose this 739 * would be a good thing to turn on if the kernel is still flakey. 740 */ 741 if (mp->mnt_flag & MNT_SYNCHRONOUS) 742 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 743 744 /* 745 * Finish up. 746 */ 747 if (ronly) 748 pmp->pm_flags |= MSDOSFSMNT_RONLY; 749 else { 750 if ((error = markvoldirty(pmp, 1)) != 0) { 751 (void)markvoldirty(pmp, 0); 752 goto error_exit; 753 } 754 pmp->pm_fmod = 1; 755 } 756 mp->mnt_data = pmp; 757 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 758 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 759 MNT_ILOCK(mp); 760 mp->mnt_flag |= MNT_LOCAL; 761 mp->mnt_kern_flag |= MNTK_USES_BCACHE; 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 g_topology_lock(); 774 g_vfs_close(cp); 775 g_topology_unlock(); 776 } 777 if (pmp) { 778 lockdestroy(&pmp->pm_fatlock); 779 if (pmp->pm_inusemap) 780 free(pmp->pm_inusemap, M_MSDOSFSFAT); 781 free(pmp, M_MSDOSFSMNT); 782 mp->mnt_data = NULL; 783 } 784 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 785 dev_rel(dev); 786 return (error); 787 } 788 789 /* 790 * Unmount the filesystem described by mp. 791 */ 792 static int 793 msdosfs_unmount(struct mount *mp, int mntflags) 794 { 795 struct msdosfsmount *pmp; 796 int error, flags; 797 798 error = flags = 0; 799 pmp = VFSTOMSDOSFS(mp); 800 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) 801 error = msdosfs_sync(mp, MNT_WAIT); 802 if ((mntflags & MNT_FORCE) != 0) 803 flags |= FORCECLOSE; 804 else if (error != 0) 805 return (error); 806 error = vflush(mp, 0, flags, curthread); 807 if (error != 0 && error != ENXIO) 808 return (error); 809 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 810 error = markvoldirty(pmp, 0); 811 if (error && error != ENXIO) { 812 (void)markvoldirty(pmp, 1); 813 return (error); 814 } 815 } 816 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 817 if (pmp->pm_w2u) 818 msdosfs_iconv->close(pmp->pm_w2u); 819 if (pmp->pm_u2w) 820 msdosfs_iconv->close(pmp->pm_u2w); 821 if (pmp->pm_d2u) 822 msdosfs_iconv->close(pmp->pm_d2u); 823 if (pmp->pm_u2d) 824 msdosfs_iconv->close(pmp->pm_u2d); 825 } 826 827 #ifdef MSDOSFS_DEBUG 828 { 829 struct vnode *vp = pmp->pm_devvp; 830 struct bufobj *bo; 831 832 bo = &vp->v_bufobj; 833 BO_LOCK(bo); 834 VI_LOCK(vp); 835 vn_printf(vp, 836 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 837 printf("freef %p, freeb %p, mount %p\n", 838 TAILQ_NEXT(vp, v_actfreelist), vp->v_actfreelist.tqe_prev, 839 vp->v_mount); 840 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 841 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 842 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 843 vp->v_bufobj.bo_numoutput, vp->v_type); 844 VI_UNLOCK(vp); 845 BO_UNLOCK(bo); 846 } 847 #endif 848 g_topology_lock(); 849 g_vfs_close(pmp->pm_cp); 850 g_topology_unlock(); 851 atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0); 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: 112274952725bf2eb50e40b51dcc4f31
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