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sys/fs/msdosfs/msdosfs_vfsops.c
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1 /* $FreeBSD$ */ 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 179 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 180 return 0; 181 } 182 183 static int 184 msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags) 185 { 186 struct msdosfs_args args; 187 struct export_args exp; 188 int error; 189 190 if (data == NULL) 191 return (EINVAL); 192 error = copyin(data, &args, sizeof args); 193 if (error) 194 return (error); 195 vfs_oexport_conv(&args.export, &exp); 196 197 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 198 ma = mount_arg(ma, "export", &exp, sizeof(exp)); 199 ma = mount_argf(ma, "uid", "%d", args.uid); 200 ma = mount_argf(ma, "gid", "%d", args.gid); 201 ma = mount_argf(ma, "mask", "%d", args.mask); 202 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 203 204 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 205 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 206 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 207 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 208 209 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 210 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 211 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 212 213 error = kernel_mount(ma, flags); 214 215 return (error); 216 } 217 218 /* 219 * mp - path - addr in user space of mount point (ie /usr or whatever) 220 * data - addr in user space of mount params including the name of the block 221 * special file to treat as a filesystem. 222 */ 223 static int 224 msdosfs_mount(struct mount *mp) 225 { 226 struct vnode *devvp; /* vnode for blk device to mount */ 227 struct thread *td; 228 /* msdosfs specific mount control block */ 229 struct msdosfsmount *pmp = NULL; 230 struct nameidata ndp; 231 int error, flags; 232 accmode_t accmode; 233 char *from; 234 235 td = curthread; 236 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 237 return (EINVAL); 238 239 /* 240 * If updating, check whether changing from read-only to 241 * read/write; if there is no device name, that's all we do. 242 */ 243 if (mp->mnt_flag & MNT_UPDATE) { 244 pmp = VFSTOMSDOSFS(mp); 245 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) { 246 /* 247 * Forbid export requests if filesystem has 248 * MSDOSFS_LARGEFS flag set. 249 */ 250 if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) { 251 vfs_mount_error(mp, 252 "MSDOSFS_LARGEFS flag set, cannot export"); 253 return (EOPNOTSUPP); 254 } 255 } 256 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 257 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 258 error = VFS_SYNC(mp, MNT_WAIT); 259 if (error) 260 return (error); 261 flags = WRITECLOSE; 262 if (mp->mnt_flag & MNT_FORCE) 263 flags |= FORCECLOSE; 264 error = vflush(mp, 0, flags, td); 265 if (error) 266 return (error); 267 268 /* 269 * Now the volume is clean. Mark it so while the 270 * device is still rw. 271 */ 272 error = markvoldirty(pmp, 0); 273 if (error) { 274 (void)markvoldirty(pmp, 1); 275 return (error); 276 } 277 278 /* Downgrade the device from rw to ro. */ 279 DROP_GIANT(); 280 g_topology_lock(); 281 error = g_access(pmp->pm_cp, 0, -1, 0); 282 g_topology_unlock(); 283 PICKUP_GIANT(); 284 if (error) { 285 (void)markvoldirty(pmp, 1); 286 return (error); 287 } 288 289 /* 290 * Backing out after an error was painful in the 291 * above. Now we are committed to succeeding. 292 */ 293 pmp->pm_fmod = 0; 294 pmp->pm_flags |= MSDOSFSMNT_RONLY; 295 MNT_ILOCK(mp); 296 mp->mnt_flag |= MNT_RDONLY; 297 MNT_IUNLOCK(mp); 298 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 299 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 300 /* 301 * If upgrade to read-write by non-root, then verify 302 * that user has necessary permissions on the device. 303 */ 304 devvp = pmp->pm_devvp; 305 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 306 error = VOP_ACCESS(devvp, VREAD | VWRITE, 307 td->td_ucred, td); 308 if (error) 309 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 310 if (error) { 311 VOP_UNLOCK(devvp, 0); 312 return (error); 313 } 314 VOP_UNLOCK(devvp, 0); 315 DROP_GIANT(); 316 g_topology_lock(); 317 error = g_access(pmp->pm_cp, 0, 1, 0); 318 g_topology_unlock(); 319 PICKUP_GIANT(); 320 if (error) 321 return (error); 322 323 pmp->pm_fmod = 1; 324 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 325 MNT_ILOCK(mp); 326 mp->mnt_flag &= ~MNT_RDONLY; 327 MNT_IUNLOCK(mp); 328 329 /* Now that the volume is modifiable, mark it dirty. */ 330 error = markvoldirty(pmp, 1); 331 if (error) 332 return (error); 333 } 334 } 335 /* 336 * Not an update, or updating the name: look up the name 337 * and verify that it refers to a sensible disk device. 338 */ 339 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 340 return (EINVAL); 341 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 342 error = namei(&ndp); 343 if (error) 344 return (error); 345 devvp = ndp.ni_vp; 346 NDFREE(&ndp, NDF_ONLY_PNBUF); 347 348 if (!vn_isdisk(devvp, &error)) { 349 vput(devvp); 350 return (error); 351 } 352 /* 353 * If mount by non-root, then verify that user has necessary 354 * permissions on the device. 355 */ 356 accmode = VREAD; 357 if ((mp->mnt_flag & MNT_RDONLY) == 0) 358 accmode |= VWRITE; 359 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 360 if (error) 361 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 362 if (error) { 363 vput(devvp); 364 return (error); 365 } 366 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 367 error = mountmsdosfs(devvp, mp); 368 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 369 pmp = VFSTOMSDOSFS(mp); 370 #endif 371 } else { 372 vput(devvp); 373 if (devvp != pmp->pm_devvp) 374 return (EINVAL); /* XXX needs translation */ 375 } 376 if (error) { 377 vrele(devvp); 378 return (error); 379 } 380 381 error = update_mp(mp, td); 382 if (error) { 383 if ((mp->mnt_flag & MNT_UPDATE) == 0) 384 msdosfs_unmount(mp, MNT_FORCE); 385 return error; 386 } 387 388 if (devvp->v_type == VCHR && devvp->v_rdev != NULL) 389 devvp->v_rdev->si_mountpt = mp; 390 vfs_mountedfrom(mp, from); 391 #ifdef MSDOSFS_DEBUG 392 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 393 #endif 394 return (0); 395 } 396 397 static int 398 mountmsdosfs(struct vnode *devvp, struct mount *mp) 399 { 400 struct msdosfsmount *pmp; 401 struct buf *bp; 402 struct cdev *dev; 403 union bootsector *bsp; 404 struct byte_bpb33 *b33; 405 struct byte_bpb50 *b50; 406 struct byte_bpb710 *b710; 407 u_int8_t SecPerClust; 408 u_long clusters; 409 int ronly, error; 410 struct g_consumer *cp; 411 struct bufobj *bo; 412 413 bp = NULL; /* This and pmp both used in error_exit. */ 414 pmp = NULL; 415 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 416 417 dev = devvp->v_rdev; 418 dev_ref(dev); 419 DROP_GIANT(); 420 g_topology_lock(); 421 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 422 g_topology_unlock(); 423 PICKUP_GIANT(); 424 VOP_UNLOCK(devvp, 0); 425 if (error) 426 goto error_exit; 427 428 bo = &devvp->v_bufobj; 429 430 /* 431 * Read the boot sector of the filesystem, and then check the 432 * boot signature. If not a dos boot sector then error out. 433 * 434 * NOTE: 8192 is a magic size that works for ffs. 435 */ 436 error = bread(devvp, 0, 8192, NOCRED, &bp); 437 if (error) 438 goto error_exit; 439 bp->b_flags |= B_AGE; 440 bsp = (union bootsector *)bp->b_data; 441 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 442 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 443 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 444 445 #ifndef MSDOSFS_NOCHECKSIG 446 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 447 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 448 error = EINVAL; 449 goto error_exit; 450 } 451 #endif 452 453 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 454 pmp->pm_mountp = mp; 455 pmp->pm_cp = cp; 456 pmp->pm_bo = bo; 457 458 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); 459 460 /* 461 * Initialize ownerships and permissions, since nothing else will 462 * initialize them iff we are mounting root. 463 */ 464 pmp->pm_uid = UID_ROOT; 465 pmp->pm_gid = GID_WHEEL; 466 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 467 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 468 469 /* 470 * Experimental support for large MS-DOS filesystems. 471 * WARNING: This uses at least 32 bytes of kernel memory (which is not 472 * reclaimed until the FS is unmounted) for each file on disk to map 473 * between the 32-bit inode numbers used by VFS and the 64-bit 474 * pseudo-inode numbers used internally by msdosfs. This is only 475 * safe to use in certain controlled situations (e.g. read-only FS 476 * with less than 1 million files). 477 * Since the mappings do not persist across unmounts (or reboots), these 478 * filesystems are not suitable for exporting through NFS, or any other 479 * application that requires fixed inode numbers. 480 */ 481 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS); 482 483 /* 484 * Compute several useful quantities from the bpb in the 485 * bootsector. Copy in the dos 5 variant of the bpb then fix up 486 * the fields that are different between dos 5 and dos 3.3. 487 */ 488 SecPerClust = b50->bpbSecPerClust; 489 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 490 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 491 error = EINVAL; 492 goto error_exit; 493 } 494 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 495 pmp->pm_FATs = b50->bpbFATs; 496 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 497 pmp->pm_Sectors = getushort(b50->bpbSectors); 498 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 499 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 500 pmp->pm_Heads = getushort(b50->bpbHeads); 501 pmp->pm_Media = b50->bpbMedia; 502 503 /* calculate the ratio of sector size to DEV_BSIZE */ 504 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 505 506 /* 507 * We don't check pm_Heads nor pm_SecPerTrack, because 508 * these may not be set for EFI file systems. We don't 509 * use these anyway, so we're unaffected if they are 510 * invalid. 511 */ 512 if (!pmp->pm_BytesPerSec || !SecPerClust) { 513 error = EINVAL; 514 goto error_exit; 515 } 516 517 if (pmp->pm_Sectors == 0) { 518 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 519 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 520 } else { 521 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 522 pmp->pm_HugeSectors = pmp->pm_Sectors; 523 } 524 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) { 525 if (pmp->pm_HugeSectors > 0xffffffff / 526 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) { 527 /* 528 * We cannot deal currently with this size of disk 529 * due to fileid limitations (see msdosfs_getattr and 530 * msdosfs_readdir) 531 */ 532 error = EINVAL; 533 vfs_mount_error(mp, 534 "Disk too big, try '-o large' mount option"); 535 goto error_exit; 536 } 537 } 538 539 if (pmp->pm_RootDirEnts == 0) { 540 if (pmp->pm_FATsecs 541 || getushort(b710->bpbFSVers)) { 542 error = EINVAL; 543 #ifdef MSDOSFS_DEBUG 544 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 545 #endif 546 goto error_exit; 547 } 548 pmp->pm_fatmask = FAT32_MASK; 549 pmp->pm_fatmult = 4; 550 pmp->pm_fatdiv = 1; 551 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 552 if (getushort(b710->bpbExtFlags) & FATMIRROR) 553 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 554 else 555 pmp->pm_flags |= MSDOSFS_FATMIRROR; 556 } else 557 pmp->pm_flags |= MSDOSFS_FATMIRROR; 558 559 /* 560 * Check a few values (could do some more): 561 * - logical sector size: power of 2, >= block size 562 * - sectors per cluster: power of 2, >= 1 563 * - number of sectors: >= 1, <= size of partition 564 * - number of FAT sectors: >= 1 565 */ 566 if ( (SecPerClust == 0) 567 || (SecPerClust & (SecPerClust - 1)) 568 || (pmp->pm_BytesPerSec < DEV_BSIZE) 569 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 570 || (pmp->pm_HugeSectors == 0) 571 || (pmp->pm_FATsecs == 0) 572 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) 573 ) { 574 error = EINVAL; 575 goto error_exit; 576 } 577 578 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 579 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 580 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 581 SecPerClust *= pmp->pm_BlkPerSec; 582 583 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 584 585 if (FAT32(pmp)) { 586 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 587 pmp->pm_firstcluster = pmp->pm_fatblk 588 + (pmp->pm_FATs * pmp->pm_FATsecs); 589 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 590 } else { 591 pmp->pm_rootdirblk = pmp->pm_fatblk + 592 (pmp->pm_FATs * pmp->pm_FATsecs); 593 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 594 + DEV_BSIZE - 1) 595 / DEV_BSIZE; /* in blocks */ 596 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 597 } 598 599 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 600 SecPerClust + 1; 601 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 602 603 if (pmp->pm_fatmask == 0) { 604 if (pmp->pm_maxcluster 605 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 606 /* 607 * This will usually be a floppy disk. This size makes 608 * sure that one fat entry will not be split across 609 * multiple blocks. 610 */ 611 pmp->pm_fatmask = FAT12_MASK; 612 pmp->pm_fatmult = 3; 613 pmp->pm_fatdiv = 2; 614 } else { 615 pmp->pm_fatmask = FAT16_MASK; 616 pmp->pm_fatmult = 2; 617 pmp->pm_fatdiv = 1; 618 } 619 } 620 621 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 622 if (pmp->pm_maxcluster >= clusters) { 623 #ifdef MSDOSFS_DEBUG 624 printf("Warning: number of clusters (%ld) exceeds FAT " 625 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 626 #endif 627 pmp->pm_maxcluster = clusters - 1; 628 } 629 630 if (FAT12(pmp)) 631 pmp->pm_fatblocksize = 3 * 512; 632 else 633 pmp->pm_fatblocksize = PAGE_SIZE; 634 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 635 pmp->pm_BytesPerSec); 636 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 637 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 638 639 /* 640 * Compute mask and shift value for isolating cluster relative byte 641 * offsets and cluster numbers from a file offset. 642 */ 643 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 644 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 645 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 646 647 /* 648 * Check for valid cluster size 649 * must be a power of 2 650 */ 651 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 652 error = EINVAL; 653 goto error_exit; 654 } 655 656 /* 657 * Release the bootsector buffer. 658 */ 659 brelse(bp); 660 bp = NULL; 661 662 /* 663 * Check the fsinfo sector if we have one. Silently fix up our 664 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 665 * or too large. Ignore fp->fsinfree for now, since we need to 666 * read the entire FAT anyway to fill the inuse map. 667 */ 668 if (pmp->pm_fsinfo) { 669 struct fsinfo *fp; 670 671 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 672 NOCRED, &bp)) != 0) 673 goto error_exit; 674 fp = (struct fsinfo *)bp->b_data; 675 if (!bcmp(fp->fsisig1, "RRaA", 4) 676 && !bcmp(fp->fsisig2, "rrAa", 4) 677 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 678 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 679 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 680 pmp->pm_nxtfree = CLUST_FIRST; 681 } else 682 pmp->pm_fsinfo = 0; 683 brelse(bp); 684 bp = NULL; 685 } 686 687 /* 688 * Finish initializing pmp->pm_nxtfree (just in case the first few 689 * sectors aren't properly reserved in the FAT). This completes 690 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 691 * value if there is no fsinfo. We will use pmp->pm_nxtfree 692 * internally even if there is no fsinfo. 693 */ 694 if (pmp->pm_nxtfree < CLUST_FIRST) 695 pmp->pm_nxtfree = CLUST_FIRST; 696 697 /* 698 * Allocate memory for the bitmap of allocated clusters, and then 699 * fill it in. 700 */ 701 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 702 * sizeof(*pmp->pm_inusemap), 703 M_MSDOSFSFAT, M_WAITOK); 704 705 /* 706 * fillinusemap() needs pm_devvp. 707 */ 708 pmp->pm_devvp = devvp; 709 pmp->pm_dev = dev; 710 711 /* 712 * Have the inuse map filled in. 713 */ 714 MSDOSFS_LOCK_MP(pmp); 715 error = fillinusemap(pmp); 716 MSDOSFS_UNLOCK_MP(pmp); 717 if (error != 0) 718 goto error_exit; 719 720 /* 721 * If they want fat updates to be synchronous then let them suffer 722 * the performance degradation in exchange for the on disk copy of 723 * the fat being correct just about all the time. I suppose this 724 * would be a good thing to turn on if the kernel is still flakey. 725 */ 726 if (mp->mnt_flag & MNT_SYNCHRONOUS) 727 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 728 729 /* 730 * Finish up. 731 */ 732 if (ronly) 733 pmp->pm_flags |= MSDOSFSMNT_RONLY; 734 else { 735 if ((error = markvoldirty(pmp, 1)) != 0) { 736 (void)markvoldirty(pmp, 0); 737 goto error_exit; 738 } 739 pmp->pm_fmod = 1; 740 } 741 mp->mnt_data = pmp; 742 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 743 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 744 MNT_ILOCK(mp); 745 mp->mnt_flag |= MNT_LOCAL; 746 mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF; 747 MNT_IUNLOCK(mp); 748 749 if (pmp->pm_flags & MSDOSFS_LARGEFS) 750 msdosfs_fileno_init(mp); 751 752 return 0; 753 754 error_exit: 755 if (bp) 756 brelse(bp); 757 if (cp != NULL) { 758 DROP_GIANT(); 759 g_topology_lock(); 760 g_vfs_close(cp); 761 g_topology_unlock(); 762 PICKUP_GIANT(); 763 } 764 if (pmp) { 765 lockdestroy(&pmp->pm_fatlock); 766 free(pmp->pm_inusemap, M_MSDOSFSFAT); 767 free(pmp, M_MSDOSFSMNT); 768 mp->mnt_data = NULL; 769 } 770 dev_rel(dev); 771 return (error); 772 } 773 774 /* 775 * Unmount the filesystem described by mp. 776 */ 777 static int 778 msdosfs_unmount(struct mount *mp, int mntflags) 779 { 780 struct msdosfsmount *pmp; 781 int error, flags; 782 783 error = flags = 0; 784 pmp = VFSTOMSDOSFS(mp); 785 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) 786 error = msdosfs_sync(mp, MNT_WAIT); 787 if ((mntflags & MNT_FORCE) != 0) 788 flags |= FORCECLOSE; 789 else if (error != 0) 790 return (error); 791 error = vflush(mp, 0, flags, curthread); 792 if (error != 0 && error != ENXIO) 793 return (error); 794 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 795 error = markvoldirty(pmp, 0); 796 if (error && error != ENXIO) { 797 (void)markvoldirty(pmp, 1); 798 return (error); 799 } 800 } 801 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 802 if (pmp->pm_w2u) 803 msdosfs_iconv->close(pmp->pm_w2u); 804 if (pmp->pm_u2w) 805 msdosfs_iconv->close(pmp->pm_u2w); 806 if (pmp->pm_d2u) 807 msdosfs_iconv->close(pmp->pm_d2u); 808 if (pmp->pm_u2d) 809 msdosfs_iconv->close(pmp->pm_u2d); 810 } 811 812 #ifdef MSDOSFS_DEBUG 813 { 814 struct vnode *vp = pmp->pm_devvp; 815 struct bufobj *bo; 816 817 bo = &vp->v_bufobj; 818 BO_LOCK(bo); 819 VI_LOCK(vp); 820 vn_printf(vp, 821 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 822 printf("freef %p, freeb %p, mount %p\n", 823 TAILQ_NEXT(vp, v_actfreelist), vp->v_actfreelist.tqe_prev, 824 vp->v_mount); 825 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 826 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 827 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 828 vp->v_bufobj.bo_numoutput, vp->v_type); 829 VI_UNLOCK(vp); 830 BO_UNLOCK(bo); 831 } 832 #endif 833 DROP_GIANT(); 834 if (pmp->pm_devvp->v_type == VCHR && pmp->pm_devvp->v_rdev != NULL) 835 pmp->pm_devvp->v_rdev->si_mountpt = NULL; 836 g_topology_lock(); 837 g_vfs_close(pmp->pm_cp); 838 g_topology_unlock(); 839 PICKUP_GIANT(); 840 vrele(pmp->pm_devvp); 841 dev_rel(pmp->pm_dev); 842 free(pmp->pm_inusemap, M_MSDOSFSFAT); 843 if (pmp->pm_flags & MSDOSFS_LARGEFS) 844 msdosfs_fileno_free(mp); 845 lockdestroy(&pmp->pm_fatlock); 846 free(pmp, M_MSDOSFSMNT); 847 mp->mnt_data = NULL; 848 MNT_ILOCK(mp); 849 mp->mnt_flag &= ~MNT_LOCAL; 850 MNT_IUNLOCK(mp); 851 return (error); 852 } 853 854 static int 855 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 856 { 857 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 858 struct denode *ndep; 859 int error; 860 861 #ifdef MSDOSFS_DEBUG 862 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 863 #endif 864 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 865 if (error) 866 return (error); 867 *vpp = DETOV(ndep); 868 return (0); 869 } 870 871 static int 872 msdosfs_statfs(struct mount *mp, struct statfs *sbp) 873 { 874 struct msdosfsmount *pmp; 875 876 pmp = VFSTOMSDOSFS(mp); 877 sbp->f_bsize = pmp->pm_bpcluster; 878 sbp->f_iosize = pmp->pm_bpcluster; 879 sbp->f_blocks = pmp->pm_maxcluster + 1; 880 sbp->f_bfree = pmp->pm_freeclustercount; 881 sbp->f_bavail = pmp->pm_freeclustercount; 882 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 883 sbp->f_ffree = 0; /* what to put in here? */ 884 return (0); 885 } 886 887 /* 888 * If we have an FSInfo block, update it. 889 */ 890 static int 891 msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) 892 { 893 struct fsinfo *fp; 894 struct buf *bp; 895 int error; 896 897 MSDOSFS_LOCK_MP(pmp); 898 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { 899 error = 0; 900 goto unlock; 901 } 902 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 903 NOCRED, &bp); 904 if (error != 0) { 905 brelse(bp); 906 goto unlock; 907 } 908 fp = (struct fsinfo *)bp->b_data; 909 putulong(fp->fsinfree, pmp->pm_freeclustercount); 910 putulong(fp->fsinxtfree, pmp->pm_nxtfree); 911 pmp->pm_flags &= ~MSDOSFS_FSIMOD; 912 if (waitfor == MNT_WAIT) 913 error = bwrite(bp); 914 else 915 bawrite(bp); 916 unlock: 917 MSDOSFS_UNLOCK_MP(pmp); 918 return (error); 919 } 920 921 static int 922 msdosfs_sync(struct mount *mp, int waitfor) 923 { 924 struct vnode *vp, *nvp; 925 struct thread *td; 926 struct denode *dep; 927 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 928 int error, allerror = 0; 929 930 td = curthread; 931 932 /* 933 * If we ever switch to not updating all of the fats all the time, 934 * this would be the place to update them from the first one. 935 */ 936 if (pmp->pm_fmod != 0) { 937 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 938 panic("msdosfs_sync: rofs mod"); 939 else { 940 /* update fats here */ 941 } 942 } 943 /* 944 * Write back each (modified) denode. 945 */ 946 loop: 947 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { 948 if (vp->v_type == VNON) { 949 VI_UNLOCK(vp); 950 continue; 951 } 952 dep = VTODE(vp); 953 if ((dep->de_flag & 954 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 955 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 956 waitfor == MNT_LAZY)) { 957 VI_UNLOCK(vp); 958 continue; 959 } 960 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 961 if (error) { 962 if (error == ENOENT) 963 goto loop; 964 continue; 965 } 966 error = VOP_FSYNC(vp, waitfor, td); 967 if (error) 968 allerror = error; 969 VOP_UNLOCK(vp, 0); 970 vrele(vp); 971 } 972 973 /* 974 * Flush filesystem control info. 975 */ 976 if (waitfor != MNT_LAZY) { 977 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 978 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 979 if (error) 980 allerror = error; 981 VOP_UNLOCK(pmp->pm_devvp, 0); 982 } 983 984 error = msdosfs_fsiflush(pmp, waitfor); 985 if (error != 0) 986 allerror = error; 987 return (allerror); 988 } 989 990 static int 991 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) 992 { 993 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 994 struct defid *defhp = (struct defid *) fhp; 995 struct denode *dep; 996 int error; 997 998 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 999 if (error) { 1000 *vpp = NULLVP; 1001 return (error); 1002 } 1003 *vpp = DETOV(dep); 1004 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 1005 return (0); 1006 } 1007 1008 static struct vfsops msdosfs_vfsops = { 1009 .vfs_fhtovp = msdosfs_fhtovp, 1010 .vfs_mount = msdosfs_mount, 1011 .vfs_cmount = msdosfs_cmount, 1012 .vfs_root = msdosfs_root, 1013 .vfs_statfs = msdosfs_statfs, 1014 .vfs_sync = msdosfs_sync, 1015 .vfs_unmount = msdosfs_unmount, 1016 }; 1017 1018 VFS_SET(msdosfs_vfsops, msdosfs, 0); 1019 MODULE_VERSION(msdosfs, 1);
Cache object: 54f43ffdf17efd644c2d5f67746b6ee5
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