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sys/fs/msdosfs/msdosfs_vfsops.c
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1 /* $FreeBSD: releng/8.0/sys/fs/msdosfs/msdosfs_vfsops.c 191990 2009-05-11 15:33:26Z attilio $ */ 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 /* Mount options that we support. */ 79 static const char *msdosfs_opts[] = { 80 "async", "noatime", "noclusterr", "noclusterw", 81 "export", "force", "from", "sync", 82 "cs_dos", "cs_local", "cs_win", "dirmask", 83 "gid", "kiconv", "large", "longname", 84 "longnames", "mask", "shortname", "shortnames", 85 "uid", "win95", "nowin95", 86 NULL 87 }; 88 89 #if 1 /*def PC98*/ 90 /* 91 * XXX - The boot signature formatted by NEC PC-98 DOS looks like a 92 * garbage or a random value :-{ 93 * If you want to use that broken-signatured media, define the 94 * following symbol even though PC/AT. 95 * (ex. mount PC-98 DOS formatted FD on PC/AT) 96 */ 97 #define MSDOSFS_NOCHECKSIG 98 #endif 99 100 MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); 101 static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); 102 103 struct iconv_functions *msdosfs_iconv; 104 105 static int update_mp(struct mount *mp, struct thread *td); 106 static int mountmsdosfs(struct vnode *devvp, struct mount *mp); 107 static vfs_fhtovp_t msdosfs_fhtovp; 108 static vfs_mount_t msdosfs_mount; 109 static vfs_root_t msdosfs_root; 110 static vfs_statfs_t msdosfs_statfs; 111 static vfs_sync_t msdosfs_sync; 112 static vfs_unmount_t msdosfs_unmount; 113 114 /* Maximum length of a character set name (arbitrary). */ 115 #define MAXCSLEN 64 116 117 static int 118 update_mp(struct mount *mp, struct thread *td) 119 { 120 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 121 void *dos, *win, *local; 122 int error, v; 123 124 if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { 125 if (msdosfs_iconv != NULL) { 126 error = vfs_getopt(mp->mnt_optnew, 127 "cs_win", &win, NULL); 128 if (!error) 129 error = vfs_getopt(mp->mnt_optnew, 130 "cs_local", &local, NULL); 131 if (!error) 132 error = vfs_getopt(mp->mnt_optnew, 133 "cs_dos", &dos, NULL); 134 if (!error) { 135 msdosfs_iconv->open(win, local, &pmp->pm_u2w); 136 msdosfs_iconv->open(local, win, &pmp->pm_w2u); 137 msdosfs_iconv->open(dos, local, &pmp->pm_u2d); 138 msdosfs_iconv->open(local, dos, &pmp->pm_d2u); 139 } 140 if (error != 0) 141 return (error); 142 } else { 143 pmp->pm_w2u = NULL; 144 pmp->pm_u2w = NULL; 145 pmp->pm_d2u = NULL; 146 pmp->pm_u2d = NULL; 147 } 148 } 149 150 if (1 == vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v)) 151 pmp->pm_gid = v; 152 if (1 == vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v)) 153 pmp->pm_uid = v; 154 if (1 == vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v)) 155 pmp->pm_mask = v & ALLPERMS; 156 if (1 == vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v)) 157 pmp->pm_dirmask = v & ALLPERMS; 158 vfs_flagopt(mp->mnt_optnew, "shortname", 159 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 160 vfs_flagopt(mp->mnt_optnew, "shortnames", 161 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 162 vfs_flagopt(mp->mnt_optnew, "longname", 163 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 164 vfs_flagopt(mp->mnt_optnew, "longnames", 165 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 166 vfs_flagopt(mp->mnt_optnew, "kiconv", 167 &pmp->pm_flags, MSDOSFSMNT_KICONV); 168 169 if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) 170 pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 171 else 172 pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; 173 174 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 175 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 176 else if (!(pmp->pm_flags & 177 (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) { 178 struct vnode *rootvp; 179 180 /* 181 * Try to divine whether to support Win'95 long filenames 182 */ 183 if (FAT32(pmp)) 184 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 185 else { 186 if ((error = 187 msdosfs_root(mp, LK_EXCLUSIVE, &rootvp)) != 0) 188 return error; 189 pmp->pm_flags |= findwin95(VTODE(rootvp)) ? 190 MSDOSFSMNT_LONGNAME : MSDOSFSMNT_SHORTNAME; 191 vput(rootvp); 192 } 193 } 194 return 0; 195 } 196 197 static int 198 msdosfs_cmount(struct mntarg *ma, void *data, int flags) 199 { 200 struct msdosfs_args args; 201 int error; 202 203 if (data == NULL) 204 return (EINVAL); 205 error = copyin(data, &args, sizeof args); 206 if (error) 207 return (error); 208 209 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 210 ma = mount_arg(ma, "export", &args.export, sizeof args.export); 211 ma = mount_argf(ma, "uid", "%d", args.uid); 212 ma = mount_argf(ma, "gid", "%d", args.gid); 213 ma = mount_argf(ma, "mask", "%d", args.mask); 214 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 215 216 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 217 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 218 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 219 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 220 221 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 222 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 223 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 224 225 error = kernel_mount(ma, flags); 226 227 return (error); 228 } 229 230 /* 231 * mp - path - addr in user space of mount point (ie /usr or whatever) 232 * data - addr in user space of mount params including the name of the block 233 * special file to treat as a filesystem. 234 */ 235 static int 236 msdosfs_mount(struct mount *mp) 237 { 238 struct vnode *devvp; /* vnode for blk device to mount */ 239 struct thread *td; 240 /* msdosfs specific mount control block */ 241 struct msdosfsmount *pmp = NULL; 242 struct nameidata ndp; 243 int error, flags; 244 accmode_t accmode; 245 char *from; 246 247 td = curthread; 248 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 249 return (EINVAL); 250 251 /* 252 * If updating, check whether changing from read-only to 253 * read/write; if there is no device name, that's all we do. 254 */ 255 if (mp->mnt_flag & MNT_UPDATE) { 256 pmp = VFSTOMSDOSFS(mp); 257 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) { 258 /* 259 * Forbid export requests if filesystem has 260 * MSDOSFS_LARGEFS flag set. 261 */ 262 if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) { 263 vfs_mount_error(mp, 264 "MSDOSFS_LARGEFS flag set, cannot export"); 265 return (EOPNOTSUPP); 266 } 267 } 268 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 269 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 270 error = VFS_SYNC(mp, MNT_WAIT); 271 if (error) 272 return (error); 273 flags = WRITECLOSE; 274 if (mp->mnt_flag & MNT_FORCE) 275 flags |= FORCECLOSE; 276 error = vflush(mp, 0, flags, td); 277 if (error) 278 return (error); 279 280 /* 281 * Now the volume is clean. Mark it so while the 282 * device is still rw. 283 */ 284 error = markvoldirty(pmp, 0); 285 if (error) { 286 (void)markvoldirty(pmp, 1); 287 return (error); 288 } 289 290 /* Downgrade the device from rw to ro. */ 291 DROP_GIANT(); 292 g_topology_lock(); 293 error = g_access(pmp->pm_cp, 0, -1, 0); 294 g_topology_unlock(); 295 PICKUP_GIANT(); 296 if (error) { 297 (void)markvoldirty(pmp, 1); 298 return (error); 299 } 300 301 /* 302 * Backing out after an error was painful in the 303 * above. Now we are committed to succeeding. 304 */ 305 pmp->pm_fmod = 0; 306 pmp->pm_flags |= MSDOSFSMNT_RONLY; 307 MNT_ILOCK(mp); 308 mp->mnt_flag |= MNT_RDONLY; 309 MNT_IUNLOCK(mp); 310 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 311 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 312 /* 313 * If upgrade to read-write by non-root, then verify 314 * that user has necessary permissions on the device. 315 */ 316 devvp = pmp->pm_devvp; 317 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 318 error = VOP_ACCESS(devvp, VREAD | VWRITE, 319 td->td_ucred, td); 320 if (error) 321 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 322 if (error) { 323 VOP_UNLOCK(devvp, 0); 324 return (error); 325 } 326 VOP_UNLOCK(devvp, 0); 327 DROP_GIANT(); 328 g_topology_lock(); 329 error = g_access(pmp->pm_cp, 0, 1, 0); 330 g_topology_unlock(); 331 PICKUP_GIANT(); 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 if (devvp != pmp->pm_devvp) 385 error = EINVAL; /* XXX needs translation */ 386 else 387 vput(devvp); 388 } 389 if (error) { 390 vrele(devvp); 391 return (error); 392 } 393 394 error = update_mp(mp, td); 395 if (error) { 396 if ((mp->mnt_flag & MNT_UPDATE) == 0) 397 msdosfs_unmount(mp, MNT_FORCE); 398 return error; 399 } 400 401 vfs_mountedfrom(mp, from); 402 #ifdef MSDOSFS_DEBUG 403 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 404 #endif 405 return (0); 406 } 407 408 static int 409 mountmsdosfs(struct vnode *devvp, struct mount *mp) 410 { 411 struct msdosfsmount *pmp; 412 struct buf *bp; 413 struct cdev *dev; 414 union bootsector *bsp; 415 struct byte_bpb33 *b33; 416 struct byte_bpb50 *b50; 417 struct byte_bpb710 *b710; 418 u_int8_t SecPerClust; 419 u_long clusters; 420 int ronly, error; 421 struct g_consumer *cp; 422 struct bufobj *bo; 423 424 bp = NULL; /* This and pmp both used in error_exit. */ 425 pmp = NULL; 426 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 427 428 dev = devvp->v_rdev; 429 dev_ref(dev); 430 DROP_GIANT(); 431 g_topology_lock(); 432 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 433 g_topology_unlock(); 434 PICKUP_GIANT(); 435 VOP_UNLOCK(devvp, 0); 436 if (error) 437 goto error_exit; 438 439 bo = &devvp->v_bufobj; 440 441 /* 442 * Read the boot sector of the filesystem, and then check the 443 * boot signature. If not a dos boot sector then error out. 444 * 445 * NOTE: 8192 is a magic size that works for ffs. 446 */ 447 error = bread(devvp, 0, 8192, NOCRED, &bp); 448 if (error) 449 goto error_exit; 450 bp->b_flags |= B_AGE; 451 bsp = (union bootsector *)bp->b_data; 452 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 453 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 454 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 455 456 #ifndef MSDOSFS_NOCHECKSIG 457 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 458 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 459 error = EINVAL; 460 goto error_exit; 461 } 462 #endif 463 464 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 465 pmp->pm_mountp = mp; 466 pmp->pm_cp = cp; 467 pmp->pm_bo = bo; 468 469 /* 470 * Initialize ownerships and permissions, since nothing else will 471 * initialize them iff we are mounting root. 472 */ 473 pmp->pm_uid = UID_ROOT; 474 pmp->pm_gid = GID_WHEEL; 475 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 476 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 477 478 /* 479 * Experimental support for large MS-DOS filesystems. 480 * WARNING: This uses at least 32 bytes of kernel memory (which is not 481 * reclaimed until the FS is unmounted) for each file on disk to map 482 * between the 32-bit inode numbers used by VFS and the 64-bit 483 * pseudo-inode numbers used internally by msdosfs. This is only 484 * safe to use in certain controlled situations (e.g. read-only FS 485 * with less than 1 million files). 486 * Since the mappings do not persist across unmounts (or reboots), these 487 * filesystems are not suitable for exporting through NFS, or any other 488 * application that requires fixed inode numbers. 489 */ 490 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS); 491 492 /* 493 * Compute several useful quantities from the bpb in the 494 * bootsector. Copy in the dos 5 variant of the bpb then fix up 495 * the fields that are different between dos 5 and dos 3.3. 496 */ 497 SecPerClust = b50->bpbSecPerClust; 498 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 499 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 500 error = EINVAL; 501 goto error_exit; 502 } 503 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 504 pmp->pm_FATs = b50->bpbFATs; 505 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 506 pmp->pm_Sectors = getushort(b50->bpbSectors); 507 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 508 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 509 pmp->pm_Heads = getushort(b50->bpbHeads); 510 pmp->pm_Media = b50->bpbMedia; 511 512 /* calculate the ratio of sector size to DEV_BSIZE */ 513 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 514 515 /* 516 * We don't check pm_Heads nor pm_SecPerTrack, because 517 * these may not be set for EFI file systems. We don't 518 * use these anyway, so we're unaffected if they are 519 * invalid. 520 */ 521 if (!pmp->pm_BytesPerSec || !SecPerClust) { 522 error = EINVAL; 523 goto error_exit; 524 } 525 526 if (pmp->pm_Sectors == 0) { 527 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 528 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 529 } else { 530 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 531 pmp->pm_HugeSectors = pmp->pm_Sectors; 532 } 533 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) { 534 if (pmp->pm_HugeSectors > 0xffffffff / 535 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) { 536 /* 537 * We cannot deal currently with this size of disk 538 * due to fileid limitations (see msdosfs_getattr and 539 * msdosfs_readdir) 540 */ 541 error = EINVAL; 542 vfs_mount_error(mp, 543 "Disk too big, try '-o large' mount option"); 544 goto error_exit; 545 } 546 } 547 548 if (pmp->pm_RootDirEnts == 0) { 549 if (pmp->pm_Sectors 550 || pmp->pm_FATsecs 551 || getushort(b710->bpbFSVers)) { 552 error = EINVAL; 553 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 554 goto error_exit; 555 } 556 pmp->pm_fatmask = FAT32_MASK; 557 pmp->pm_fatmult = 4; 558 pmp->pm_fatdiv = 1; 559 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 560 if (getushort(b710->bpbExtFlags) & FATMIRROR) 561 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 562 else 563 pmp->pm_flags |= MSDOSFS_FATMIRROR; 564 } else 565 pmp->pm_flags |= MSDOSFS_FATMIRROR; 566 567 /* 568 * Check a few values (could do some more): 569 * - logical sector size: power of 2, >= block size 570 * - sectors per cluster: power of 2, >= 1 571 * - number of sectors: >= 1, <= size of partition 572 * - number of FAT sectors: >= 1 573 */ 574 if ( (SecPerClust == 0) 575 || (SecPerClust & (SecPerClust - 1)) 576 || (pmp->pm_BytesPerSec < DEV_BSIZE) 577 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 578 || (pmp->pm_HugeSectors == 0) 579 || (pmp->pm_FATsecs == 0) 580 ) { 581 error = EINVAL; 582 goto error_exit; 583 } 584 585 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 586 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 587 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 588 SecPerClust *= pmp->pm_BlkPerSec; 589 590 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 591 592 if (FAT32(pmp)) { 593 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 594 pmp->pm_firstcluster = pmp->pm_fatblk 595 + (pmp->pm_FATs * pmp->pm_FATsecs); 596 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 597 } else { 598 pmp->pm_rootdirblk = pmp->pm_fatblk + 599 (pmp->pm_FATs * pmp->pm_FATsecs); 600 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 601 + DEV_BSIZE - 1) 602 / DEV_BSIZE; /* in blocks */ 603 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 604 } 605 606 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 607 SecPerClust + 1; 608 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 609 610 if (pmp->pm_fatmask == 0) { 611 if (pmp->pm_maxcluster 612 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 613 /* 614 * This will usually be a floppy disk. This size makes 615 * sure that one fat entry will not be split across 616 * multiple blocks. 617 */ 618 pmp->pm_fatmask = FAT12_MASK; 619 pmp->pm_fatmult = 3; 620 pmp->pm_fatdiv = 2; 621 } else { 622 pmp->pm_fatmask = FAT16_MASK; 623 pmp->pm_fatmult = 2; 624 pmp->pm_fatdiv = 1; 625 } 626 } 627 628 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 629 if (pmp->pm_maxcluster >= clusters) { 630 printf("Warning: number of clusters (%ld) exceeds FAT " 631 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 632 pmp->pm_maxcluster = clusters - 1; 633 } 634 635 if (FAT12(pmp)) 636 pmp->pm_fatblocksize = 3 * 512; 637 else 638 pmp->pm_fatblocksize = PAGE_SIZE; 639 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 640 pmp->pm_BytesPerSec); 641 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 642 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 643 644 /* 645 * Compute mask and shift value for isolating cluster relative byte 646 * offsets and cluster numbers from a file offset. 647 */ 648 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 649 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 650 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 651 652 /* 653 * Check for valid cluster size 654 * must be a power of 2 655 */ 656 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 657 error = EINVAL; 658 goto error_exit; 659 } 660 661 /* 662 * Release the bootsector buffer. 663 */ 664 brelse(bp); 665 bp = NULL; 666 667 /* 668 * Check the fsinfo sector if we have one. Silently fix up our 669 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 670 * or too large. Ignore fp->fsinfree for now, since we need to 671 * read the entire FAT anyway to fill the inuse map. 672 */ 673 if (pmp->pm_fsinfo) { 674 struct fsinfo *fp; 675 676 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 677 NOCRED, &bp)) != 0) 678 goto error_exit; 679 fp = (struct fsinfo *)bp->b_data; 680 if (!bcmp(fp->fsisig1, "RRaA", 4) 681 && !bcmp(fp->fsisig2, "rrAa", 4) 682 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 683 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 684 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 685 pmp->pm_nxtfree = CLUST_FIRST; 686 } else 687 pmp->pm_fsinfo = 0; 688 brelse(bp); 689 bp = NULL; 690 } 691 692 /* 693 * Finish initializing pmp->pm_nxtfree (just in case the first few 694 * sectors aren't properly reserved in the FAT). This completes 695 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 696 * value if there is no fsinfo. We will use pmp->pm_nxtfree 697 * internally even if there is no fsinfo. 698 */ 699 if (pmp->pm_nxtfree < CLUST_FIRST) 700 pmp->pm_nxtfree = CLUST_FIRST; 701 702 /* 703 * Allocate memory for the bitmap of allocated clusters, and then 704 * fill it in. 705 */ 706 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 707 * sizeof(*pmp->pm_inusemap), 708 M_MSDOSFSFAT, M_WAITOK); 709 710 /* 711 * fillinusemap() needs pm_devvp. 712 */ 713 pmp->pm_devvp = devvp; 714 pmp->pm_dev = dev; 715 716 /* 717 * Have the inuse map filled in. 718 */ 719 if ((error = fillinusemap(pmp)) != 0) 720 goto error_exit; 721 722 /* 723 * If they want fat updates to be synchronous then let them suffer 724 * the performance degradation in exchange for the on disk copy of 725 * the fat being correct just about all the time. I suppose this 726 * would be a good thing to turn on if the kernel is still flakey. 727 */ 728 if (mp->mnt_flag & MNT_SYNCHRONOUS) 729 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 730 731 /* 732 * Finish up. 733 */ 734 if (ronly) 735 pmp->pm_flags |= MSDOSFSMNT_RONLY; 736 else { 737 if ((error = markvoldirty(pmp, 1)) != 0) { 738 (void)markvoldirty(pmp, 0); 739 goto error_exit; 740 } 741 pmp->pm_fmod = 1; 742 } 743 mp->mnt_data = pmp; 744 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 745 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 746 MNT_ILOCK(mp); 747 mp->mnt_flag |= MNT_LOCAL; 748 MNT_IUNLOCK(mp); 749 750 if (pmp->pm_flags & MSDOSFS_LARGEFS) 751 msdosfs_fileno_init(mp); 752 753 return 0; 754 755 error_exit: 756 if (bp) 757 brelse(bp); 758 if (cp != NULL) { 759 DROP_GIANT(); 760 g_topology_lock(); 761 g_vfs_close(cp); 762 g_topology_unlock(); 763 PICKUP_GIANT(); 764 } 765 if (pmp) { 766 if (pmp->pm_inusemap) 767 free(pmp->pm_inusemap, M_MSDOSFSFAT); 768 free(pmp, M_MSDOSFSMNT); 769 mp->mnt_data = NULL; 770 } 771 dev_rel(dev); 772 return (error); 773 } 774 775 /* 776 * Unmount the filesystem described by mp. 777 */ 778 static int 779 msdosfs_unmount(struct mount *mp, int mntflags) 780 { 781 struct msdosfsmount *pmp; 782 int error, flags; 783 784 flags = 0; 785 if (mntflags & MNT_FORCE) 786 flags |= FORCECLOSE; 787 error = vflush(mp, 0, flags, curthread); 788 if (error && error != ENXIO) 789 return error; 790 pmp = VFSTOMSDOSFS(mp); 791 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 792 error = markvoldirty(pmp, 0); 793 if (error && error != ENXIO) { 794 (void)markvoldirty(pmp, 1); 795 return (error); 796 } 797 } 798 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 799 if (pmp->pm_w2u) 800 msdosfs_iconv->close(pmp->pm_w2u); 801 if (pmp->pm_u2w) 802 msdosfs_iconv->close(pmp->pm_u2w); 803 if (pmp->pm_d2u) 804 msdosfs_iconv->close(pmp->pm_d2u); 805 if (pmp->pm_u2d) 806 msdosfs_iconv->close(pmp->pm_u2d); 807 } 808 809 #ifdef MSDOSFS_DEBUG 810 { 811 struct vnode *vp = pmp->pm_devvp; 812 struct bufobj *bo; 813 814 bo = &vp->v_bufobj; 815 BO_LOCK(bo); 816 VI_LOCK(vp); 817 vn_printf(vp, 818 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 819 printf("freef %p, freeb %p, mount %p\n", 820 TAILQ_NEXT(vp, v_freelist), vp->v_freelist.tqe_prev, 821 vp->v_mount); 822 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 823 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 824 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 825 vp->v_bufobj.bo_numoutput, vp->v_type); 826 VI_UNLOCK(vp); 827 BO_UNLOCK(bo); 828 } 829 #endif 830 DROP_GIANT(); 831 g_topology_lock(); 832 g_vfs_close(pmp->pm_cp); 833 g_topology_unlock(); 834 PICKUP_GIANT(); 835 vrele(pmp->pm_devvp); 836 dev_rel(pmp->pm_dev); 837 free(pmp->pm_inusemap, M_MSDOSFSFAT); 838 if (pmp->pm_flags & MSDOSFS_LARGEFS) 839 msdosfs_fileno_free(mp); 840 free(pmp, M_MSDOSFSMNT); 841 mp->mnt_data = NULL; 842 MNT_ILOCK(mp); 843 mp->mnt_flag &= ~MNT_LOCAL; 844 MNT_IUNLOCK(mp); 845 return (error); 846 } 847 848 static int 849 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 850 { 851 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 852 struct denode *ndep; 853 int error; 854 855 #ifdef MSDOSFS_DEBUG 856 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 857 #endif 858 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 859 if (error) 860 return (error); 861 *vpp = DETOV(ndep); 862 return (0); 863 } 864 865 static int 866 msdosfs_statfs(struct mount *mp, struct statfs *sbp) 867 { 868 struct msdosfsmount *pmp; 869 870 pmp = VFSTOMSDOSFS(mp); 871 sbp->f_bsize = pmp->pm_bpcluster; 872 sbp->f_iosize = pmp->pm_bpcluster; 873 sbp->f_blocks = pmp->pm_maxcluster + 1; 874 sbp->f_bfree = pmp->pm_freeclustercount; 875 sbp->f_bavail = pmp->pm_freeclustercount; 876 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 877 sbp->f_ffree = 0; /* what to put in here? */ 878 return (0); 879 } 880 881 static int 882 msdosfs_sync(struct mount *mp, int waitfor) 883 { 884 struct vnode *vp, *nvp; 885 struct thread *td; 886 struct denode *dep; 887 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 888 int error, allerror = 0; 889 890 td = curthread; 891 892 /* 893 * If we ever switch to not updating all of the fats all the time, 894 * this would be the place to update them from the first one. 895 */ 896 if (pmp->pm_fmod != 0) { 897 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 898 panic("msdosfs_sync: rofs mod"); 899 else { 900 /* update fats here */ 901 } 902 } 903 /* 904 * Write back each (modified) denode. 905 */ 906 MNT_ILOCK(mp); 907 loop: 908 MNT_VNODE_FOREACH(vp, mp, nvp) { 909 VI_LOCK(vp); 910 if (vp->v_type == VNON || (vp->v_iflag & VI_DOOMED)) { 911 VI_UNLOCK(vp); 912 continue; 913 } 914 MNT_IUNLOCK(mp); 915 dep = VTODE(vp); 916 if ((dep->de_flag & 917 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 918 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 919 waitfor == MNT_LAZY)) { 920 VI_UNLOCK(vp); 921 MNT_ILOCK(mp); 922 continue; 923 } 924 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 925 if (error) { 926 MNT_ILOCK(mp); 927 if (error == ENOENT) 928 goto loop; 929 continue; 930 } 931 error = VOP_FSYNC(vp, waitfor, td); 932 if (error) 933 allerror = error; 934 VOP_UNLOCK(vp, 0); 935 vrele(vp); 936 MNT_ILOCK(mp); 937 } 938 MNT_IUNLOCK(mp); 939 940 /* 941 * Flush filesystem control info. 942 */ 943 if (waitfor != MNT_LAZY) { 944 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 945 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 946 if (error) 947 allerror = error; 948 VOP_UNLOCK(pmp->pm_devvp, 0); 949 } 950 return (allerror); 951 } 952 953 static int 954 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp) 955 { 956 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 957 struct defid *defhp = (struct defid *) fhp; 958 struct denode *dep; 959 int error; 960 961 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 962 if (error) { 963 *vpp = NULLVP; 964 return (error); 965 } 966 *vpp = DETOV(dep); 967 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 968 return (0); 969 } 970 971 static struct vfsops msdosfs_vfsops = { 972 .vfs_fhtovp = msdosfs_fhtovp, 973 .vfs_mount = msdosfs_mount, 974 .vfs_cmount = msdosfs_cmount, 975 .vfs_root = msdosfs_root, 976 .vfs_statfs = msdosfs_statfs, 977 .vfs_sync = msdosfs_sync, 978 .vfs_unmount = msdosfs_unmount, 979 }; 980 981 VFS_SET(msdosfs_vfsops, msdosfs, 0); 982 MODULE_VERSION(msdosfs, 1);
Cache object: 5aac280f75ebef72a4ea3ebd090e17ce
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