msdosfs_vfsops.c revision 1.126
1 /* $NetBSD: msdosfs_vfsops.c,v 1.126 2017/04/17 08:31:01 hannken Exp $ */ 2 3 /*- 4 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. 5 * Copyright (C) 1994, 1995, 1997 TooLs GmbH. 6 * All rights reserved. 7 * Original code by Paul Popelka (paulp (at) uts.amdahl.com) (see below). 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed by TooLs GmbH. 20 * 4. The name of TooLs GmbH may not be used to endorse or promote products 21 * derived from this software without specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 24 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 25 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 26 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 27 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 28 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 29 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 30 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 31 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 32 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 33 */ 34 /* 35 * Written by Paul Popelka (paulp (at) uts.amdahl.com) 36 * 37 * You can do anything you want with this software, just don't say you wrote 38 * it, and don't remove this notice. 39 * 40 * This software is provided "as is". 41 * 42 * The author supplies this software to be publicly redistributed on the 43 * understanding that the author is not responsible for the correct 44 * functioning of this software in any circumstances and is not liable for 45 * any damages caused by this software. 46 * 47 * October 1992 48 */ 49 50 #include <sys/cdefs.h> 51 __KERNEL_RCSID(0, "$NetBSD: msdosfs_vfsops.c,v 1.126 2017/04/17 08:31:01 hannken Exp $"); 52 53 #if defined(_KERNEL_OPT) 54 #include "opt_compat_netbsd.h" 55 #endif 56 57 #include <sys/param.h> 58 #include <sys/systm.h> 59 #include <sys/sysctl.h> 60 #include <sys/namei.h> 61 #include <sys/proc.h> 62 #include <sys/kernel.h> 63 #include <sys/vnode.h> 64 #include <miscfs/genfs/genfs.h> 65 #include <miscfs/specfs/specdev.h> /* XXX */ /* defines v_rdev */ 66 #include <sys/mount.h> 67 #include <sys/buf.h> 68 #include <sys/file.h> 69 #include <sys/device.h> 70 #include <sys/disklabel.h> 71 #include <sys/disk.h> 72 #include <sys/ioctl.h> 73 #include <sys/malloc.h> 74 #include <sys/dirent.h> 75 #include <sys/stat.h> 76 #include <sys/conf.h> 77 #include <sys/kauth.h> 78 #include <sys/module.h> 79 80 #include <fs/msdosfs/bpb.h> 81 #include <fs/msdosfs/bootsect.h> 82 #include <fs/msdosfs/direntry.h> 83 #include <fs/msdosfs/denode.h> 84 #include <fs/msdosfs/msdosfsmount.h> 85 #include <fs/msdosfs/fat.h> 86 87 MODULE(MODULE_CLASS_VFS, msdos, NULL); 88 89 #ifdef MSDOSFS_DEBUG 90 #define DPRINTF(fmt, ...) uprintf("%s(): " fmt "\n", __func__, ##__VA_ARGS__) 91 #else 92 #define DPRINTF(fmt, ...) 93 #endif 94 95 #define GEMDOSFS_BSIZE 512 96 97 #define MSDOSFS_NAMEMAX(pmp) \ 98 (pmp)->pm_flags & MSDOSFSMNT_LONGNAME ? WIN_MAXLEN : 12 99 100 int msdosfs_mountfs(struct vnode *, struct mount *, struct lwp *, 101 struct msdosfs_args *); 102 103 static int update_mp(struct mount *, struct msdosfs_args *); 104 105 MALLOC_JUSTDEFINE(M_MSDOSFSMNT, "MSDOSFS mount", "MSDOS FS mount structure"); 106 MALLOC_JUSTDEFINE(M_MSDOSFSFAT, "MSDOSFS FAT", "MSDOS FS FAT table"); 107 MALLOC_JUSTDEFINE(M_MSDOSFSTMP, "MSDOSFS temp", "MSDOS FS temp. structures"); 108 109 static struct sysctllog *msdosfs_sysctl_log; 110 111 extern const struct vnodeopv_desc msdosfs_vnodeop_opv_desc; 112 113 const struct vnodeopv_desc * const msdosfs_vnodeopv_descs[] = { 114 &msdosfs_vnodeop_opv_desc, 115 NULL, 116 }; 117 118 struct vfsops msdosfs_vfsops = { 119 .vfs_name = MOUNT_MSDOS, 120 .vfs_min_mount_data = sizeof (struct msdosfs_args), 121 .vfs_mount = msdosfs_mount, 122 .vfs_start = msdosfs_start, 123 .vfs_unmount = msdosfs_unmount, 124 .vfs_root = msdosfs_root, 125 .vfs_quotactl = (void *)eopnotsupp, 126 .vfs_statvfs = msdosfs_statvfs, 127 .vfs_sync = msdosfs_sync, 128 .vfs_vget = msdosfs_vget, 129 .vfs_loadvnode = msdosfs_loadvnode, 130 .vfs_fhtovp = msdosfs_fhtovp, 131 .vfs_vptofh = msdosfs_vptofh, 132 .vfs_init = msdosfs_init, 133 .vfs_reinit = msdosfs_reinit, 134 .vfs_done = msdosfs_done, 135 .vfs_mountroot = msdosfs_mountroot, 136 .vfs_snapshot = (void *)eopnotsupp, 137 .vfs_extattrctl = vfs_stdextattrctl, 138 .vfs_suspendctl = genfs_suspendctl, 139 .vfs_renamelock_enter = genfs_renamelock_enter, 140 .vfs_renamelock_exit = genfs_renamelock_exit, 141 .vfs_fsync = (void *)eopnotsupp, 142 .vfs_opv_descs = msdosfs_vnodeopv_descs 143 }; 144 145 static int 146 msdos_modcmd(modcmd_t cmd, void *arg) 147 { 148 int error; 149 150 switch (cmd) { 151 case MODULE_CMD_INIT: 152 error = vfs_attach(&msdosfs_vfsops); 153 if (error != 0) 154 break; 155 sysctl_createv(&msdosfs_sysctl_log, 0, NULL, NULL, 156 CTLFLAG_PERMANENT, 157 CTLTYPE_NODE, "msdosfs", 158 SYSCTL_DESCR("MS-DOS file system"), 159 NULL, 0, NULL, 0, 160 CTL_VFS, 4, CTL_EOL); 161 /* 162 * XXX the "4" above could be dynamic, thereby eliminating one 163 * more instance of the "number to vfs" mapping problem, but 164 * "4" is the order as taken from sys/mount.h 165 */ 166 break; 167 case MODULE_CMD_FINI: 168 error = vfs_detach(&msdosfs_vfsops); 169 if (error != 0) 170 break; 171 sysctl_teardown(&msdosfs_sysctl_log); 172 break; 173 default: 174 error = ENOTTY; 175 break; 176 } 177 178 return (error); 179 } 180 181 static int 182 update_mp(struct mount *mp, struct msdosfs_args *argp) 183 { 184 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 185 int error; 186 187 pmp->pm_gid = argp->gid; 188 pmp->pm_uid = argp->uid; 189 pmp->pm_mask = argp->mask & ALLPERMS; 190 pmp->pm_dirmask = argp->dirmask & ALLPERMS; 191 pmp->pm_gmtoff = argp->gmtoff; 192 pmp->pm_flags |= argp->flags & MSDOSFSMNT_MNTOPT; 193 194 /* 195 * GEMDOS knows nothing about win95 long filenames 196 */ 197 if (pmp->pm_flags & MSDOSFSMNT_GEMDOSFS) 198 pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 199 200 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 201 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 202 else if (!(pmp->pm_flags & 203 (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) { 204 struct vnode *rtvp; 205 206 /* 207 * Try to divine whether to support Win'95 long filenames 208 */ 209 if (FAT32(pmp)) 210 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 211 else { 212 if ((error = msdosfs_root(mp, &rtvp)) != 0) 213 return error; 214 pmp->pm_flags |= findwin95(VTODE(rtvp)) 215 ? MSDOSFSMNT_LONGNAME 216 : MSDOSFSMNT_SHORTNAME; 217 vput(rtvp); 218 } 219 } 220 221 mp->mnt_stat.f_namemax = MSDOSFS_NAMEMAX(pmp); 222 223 return 0; 224 } 225 226 int 227 msdosfs_mountroot(void) 228 { 229 struct mount *mp; 230 struct lwp *l = curlwp; /* XXX */ 231 int error; 232 struct msdosfs_args args; 233 234 if (device_class(root_device) != DV_DISK) 235 return (ENODEV); 236 237 if ((error = vfs_rootmountalloc(MOUNT_MSDOS, "root_device", &mp))) { 238 vrele(rootvp); 239 return (error); 240 } 241 242 args.flags = MSDOSFSMNT_VERSIONED; 243 args.uid = 0; 244 args.gid = 0; 245 args.mask = 0777; 246 args.version = MSDOSFSMNT_VERSION; 247 args.dirmask = 0777; 248 249 if ((error = msdosfs_mountfs(rootvp, mp, l, &args)) != 0) { 250 vfs_unbusy(mp, false, NULL); 251 vfs_rele(mp); 252 return (error); 253 } 254 255 if ((error = update_mp(mp, &args)) != 0) { 256 (void)msdosfs_unmount(mp, 0); 257 vfs_unbusy(mp, false, NULL); 258 vfs_rele(mp); 259 vrele(rootvp); 260 return (error); 261 } 262 263 mountlist_append(mp); 264 (void)msdosfs_statvfs(mp, &mp->mnt_stat); 265 vfs_unbusy(mp, false, NULL); 266 return (0); 267 } 268 269 /* 270 * mp - path - addr in user space of mount point (ie /usr or whatever) 271 * data - addr in user space of mount params including the name of the block 272 * special file to treat as a filesystem. 273 */ 274 int 275 msdosfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len) 276 { 277 struct lwp *l = curlwp; 278 struct vnode *devvp; /* vnode for blk device to mount */ 279 struct msdosfs_args *args = data; /* holds data from mount request */ 280 /* msdosfs specific mount control block */ 281 struct msdosfsmount *pmp = NULL; 282 int error, flags; 283 mode_t accessmode; 284 285 if (args == NULL) 286 return EINVAL; 287 if (*data_len < sizeof *args) 288 return EINVAL; 289 290 if (mp->mnt_flag & MNT_GETARGS) { 291 pmp = VFSTOMSDOSFS(mp); 292 if (pmp == NULL) 293 return EIO; 294 args->fspec = NULL; 295 args->uid = pmp->pm_uid; 296 args->gid = pmp->pm_gid; 297 args->mask = pmp->pm_mask; 298 args->flags = pmp->pm_flags; 299 args->version = MSDOSFSMNT_VERSION; 300 args->dirmask = pmp->pm_dirmask; 301 args->gmtoff = pmp->pm_gmtoff; 302 *data_len = sizeof *args; 303 return 0; 304 } 305 306 /* 307 * If not versioned (i.e. using old mount_msdos(8)), fill in 308 * the additional structure items with suitable defaults. 309 */ 310 if ((args->flags & MSDOSFSMNT_VERSIONED) == 0) { 311 args->version = 1; 312 args->dirmask = args->mask; 313 } 314 315 /* 316 * Reset GMT offset for pre-v3 mount structure args. 317 */ 318 if (args->version < 3) 319 args->gmtoff = 0; 320 321 /* 322 * If updating, check whether changing from read-only to 323 * read/write; if there is no device name, that's all we do. 324 */ 325 if (mp->mnt_flag & MNT_UPDATE) { 326 pmp = VFSTOMSDOSFS(mp); 327 error = 0; 328 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 329 (mp->mnt_flag & MNT_RDONLY)) { 330 flags = WRITECLOSE; 331 if (mp->mnt_flag & MNT_FORCE) 332 flags |= FORCECLOSE; 333 error = vflush(mp, NULLVP, flags); 334 } 335 if (!error && (mp->mnt_flag & MNT_RELOAD)) 336 /* not yet implemented */ 337 error = EOPNOTSUPP; 338 if (error) { 339 DPRINTF("vflush %d", error); 340 return (error); 341 } 342 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 343 (mp->mnt_iflag & IMNT_WANTRDWR)) { 344 /* 345 * If upgrade to read-write by non-root, then verify 346 * that user has necessary permissions on the device. 347 * 348 * Permission to update a mount is checked higher, so 349 * here we presume updating the mount is okay (for 350 * example, as far as securelevel goes) which leaves us 351 * with the normal check. 352 */ 353 devvp = pmp->pm_devvp; 354 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 355 error = kauth_authorize_system(l->l_cred, 356 KAUTH_SYSTEM_MOUNT, KAUTH_REQ_SYSTEM_MOUNT_DEVICE, 357 mp, devvp, KAUTH_ARG(VREAD | VWRITE)); 358 VOP_UNLOCK(devvp); 359 DPRINTF("KAUTH_REQ_SYSTEM_MOUNT_DEVICE %d", error); 360 if (error) 361 return (error); 362 363 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 364 } 365 if (args->fspec == NULL) { 366 DPRINTF("missing fspec"); 367 return EINVAL; 368 } 369 } 370 /* 371 * Not an update, or updating the name: look up the name 372 * and verify that it refers to a sensible block device. 373 */ 374 error = namei_simple_user(args->fspec, 375 NSM_FOLLOW_NOEMULROOT, &devvp); 376 if (error != 0) { 377 DPRINTF("namei %d", error); 378 return (error); 379 } 380 381 if (devvp->v_type != VBLK) { 382 DPRINTF("not block"); 383 vrele(devvp); 384 return (ENOTBLK); 385 } 386 if (bdevsw_lookup(devvp->v_rdev) == NULL) { 387 DPRINTF("no block switch"); 388 vrele(devvp); 389 return (ENXIO); 390 } 391 /* 392 * If mount by non-root, then verify that user has necessary 393 * permissions on the device. 394 */ 395 accessmode = VREAD; 396 if ((mp->mnt_flag & MNT_RDONLY) == 0) 397 accessmode |= VWRITE; 398 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 399 error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MOUNT, 400 KAUTH_REQ_SYSTEM_MOUNT_DEVICE, mp, devvp, KAUTH_ARG(accessmode)); 401 VOP_UNLOCK(devvp); 402 if (error) { 403 DPRINTF("KAUTH_REQ_SYSTEM_MOUNT_DEVICE %d", error); 404 vrele(devvp); 405 return (error); 406 } 407 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 408 int xflags; 409 410 if (mp->mnt_flag & MNT_RDONLY) 411 xflags = FREAD; 412 else 413 xflags = FREAD|FWRITE; 414 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 415 error = VOP_OPEN(devvp, xflags, FSCRED); 416 VOP_UNLOCK(devvp); 417 if (error) { 418 DPRINTF("VOP_OPEN %d", error); 419 goto fail; 420 } 421 error = msdosfs_mountfs(devvp, mp, l, args); 422 if (error) { 423 DPRINTF("msdosfs_mountfs %d", error); 424 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 425 (void) VOP_CLOSE(devvp, xflags, NOCRED); 426 VOP_UNLOCK(devvp); 427 goto fail; 428 } 429 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 430 pmp = VFSTOMSDOSFS(mp); 431 #endif 432 } else { 433 vrele(devvp); 434 if (devvp != pmp->pm_devvp) { 435 DPRINTF("devvp %p pmp %p", devvp, pmp->pm_devvp); 436 return (EINVAL); /* needs translation */ 437 } 438 } 439 if ((error = update_mp(mp, args)) != 0) { 440 msdosfs_unmount(mp, MNT_FORCE); 441 DPRINTF("update_mp %d", error); 442 return error; 443 } 444 445 #ifdef MSDOSFS_DEBUG 446 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 447 #endif 448 return set_statvfs_info(path, UIO_USERSPACE, args->fspec, UIO_USERSPACE, 449 mp->mnt_op->vfs_name, mp, l); 450 451 fail: 452 vrele(devvp); 453 return (error); 454 } 455 456 int 457 msdosfs_mountfs(struct vnode *devvp, struct mount *mp, struct lwp *l, struct msdosfs_args *argp) 458 { 459 struct msdosfsmount *pmp; 460 struct buf *bp; 461 dev_t dev = devvp->v_rdev; 462 union bootsector *bsp; 463 struct byte_bpb33 *b33; 464 struct byte_bpb50 *b50; 465 struct byte_bpb710 *b710; 466 uint8_t SecPerClust; 467 int ronly, error, BlkPerSec; 468 uint64_t psize; 469 unsigned secsize; 470 471 /* Flush out any old buffers remaining from a previous use. */ 472 if ((error = vinvalbuf(devvp, V_SAVE, l->l_cred, l, 0, 0)) != 0) 473 return (error); 474 475 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 476 477 bp = NULL; /* both used in error_exit */ 478 pmp = NULL; 479 480 error = getdisksize(devvp, &psize, &secsize); 481 if (error) { 482 if (argp->flags & MSDOSFSMNT_GEMDOSFS) 483 goto error_exit; 484 485 /* ok, so it failed. we most likely don't need the info */ 486 secsize = DEV_BSIZE; 487 psize = 0; 488 error = 0; 489 } 490 if (secsize < DEV_BSIZE) { 491 DPRINTF("Invalid block secsize (%d < DEV_BSIZE)", secsize); 492 error = EINVAL; 493 goto error_exit; 494 } 495 496 if (argp->flags & MSDOSFSMNT_GEMDOSFS) { 497 if (secsize != GEMDOSFS_BSIZE) { 498 DPRINTF("Invalid block secsize %d for GEMDOS", secsize); 499 error = EINVAL; 500 goto error_exit; 501 } 502 } 503 504 /* 505 * Read the boot sector of the filesystem, and then check the 506 * boot signature. If not a dos boot sector then error out. 507 */ 508 if (secsize < sizeof(*b50)) { 509 DPRINTF("50 bootsec %u\n", secsize); 510 error = EINVAL; 511 goto error_exit; 512 } 513 if ((error = bread(devvp, 0, secsize, 0, &bp)) != 0) 514 goto error_exit; 515 bsp = (union bootsector *)bp->b_data; 516 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 517 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 518 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 519 520 if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) { 521 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 522 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 523 DPRINTF("bootsig0 %d bootsig1 %d", 524 bsp->bs50.bsBootSectSig0, 525 bsp->bs50.bsBootSectSig1); 526 error = EINVAL; 527 goto error_exit; 528 } 529 } 530 531 pmp = malloc(sizeof(*pmp), M_MSDOSFSMNT, M_WAITOK|M_ZERO); 532 pmp->pm_mountp = mp; 533 534 /* 535 * Compute several useful quantities from the bpb in the 536 * bootsector. Copy in the dos 5 variant of the bpb then fix up 537 * the fields that are different between dos 5 and dos 3.3. 538 */ 539 SecPerClust = b50->bpbSecPerClust; 540 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 541 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 542 pmp->pm_FATs = b50->bpbFATs; 543 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 544 pmp->pm_Sectors = getushort(b50->bpbSectors); 545 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 546 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 547 pmp->pm_Heads = getushort(b50->bpbHeads); 548 pmp->pm_Media = b50->bpbMedia; 549 550 if (pmp->pm_Sectors == 0) { 551 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 552 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 553 } else { 554 if (secsize < sizeof(*b33)) { 555 DPRINTF("33 bootsec %u\n", secsize); 556 error = EINVAL; 557 goto error_exit; 558 } 559 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 560 pmp->pm_HugeSectors = pmp->pm_Sectors; 561 } 562 563 /* 564 * Sanity checks, from the FAT specification: 565 * - sectors per cluster: >= 1, power of 2 566 * - logical sector size: >= 1, power of 2 567 * - cluster size: <= max FS block size 568 * - number of sectors: >= 1 569 */ 570 if ((SecPerClust == 0) || !powerof2(SecPerClust) || 571 (pmp->pm_BytesPerSec == 0) || !powerof2(pmp->pm_BytesPerSec) || 572 (SecPerClust * pmp->pm_BytesPerSec > MAXBSIZE) || 573 (pmp->pm_HugeSectors == 0)) { 574 DPRINTF("consistency checks"); 575 error = EINVAL; 576 goto error_exit; 577 } 578 579 if (!(argp->flags & MSDOSFSMNT_GEMDOSFS) && 580 (pmp->pm_SecPerTrack > 63)) { 581 DPRINTF("SecPerTrack %d", pmp->pm_SecPerTrack); 582 error = EINVAL; 583 goto error_exit; 584 } 585 586 if (pmp->pm_RootDirEnts == 0) { 587 if (secsize < sizeof(*b710)) { 588 DPRINTF("710 bootsec %u\n", secsize); 589 error = EINVAL; 590 goto error_exit; 591 } 592 unsigned short FSVers = getushort(b710->bpbFSVers); 593 unsigned short ExtFlags = getushort(b710->bpbExtFlags); 594 /* 595 * Some say that bsBootSectSig[23] must be zero, but 596 * Windows does not require this and some digital cameras 597 * do not set these to zero. Therefore, do not insist. 598 */ 599 if (pmp->pm_Sectors || pmp->pm_FATsecs || FSVers) { 600 DPRINTF("Sectors %d FATsecs %lu FSVers %d", 601 pmp->pm_Sectors, pmp->pm_FATsecs, FSVers); 602 error = EINVAL; 603 goto error_exit; 604 } 605 pmp->pm_fatmask = FAT32_MASK; 606 pmp->pm_fatmult = 4; 607 pmp->pm_fatdiv = 1; 608 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 609 610 /* Mirroring is enabled if the FATMIRROR bit is not set. */ 611 if ((ExtFlags & FATMIRROR) == 0) 612 pmp->pm_flags |= MSDOSFS_FATMIRROR; 613 else 614 pmp->pm_curfat = ExtFlags & FATNUM; 615 } else 616 pmp->pm_flags |= MSDOSFS_FATMIRROR; 617 618 if (argp->flags & MSDOSFSMNT_GEMDOSFS) { 619 if (FAT32(pmp)) { 620 /* GEMDOS doesn't know FAT32. */ 621 DPRINTF("FAT32 for GEMDOS"); 622 error = EINVAL; 623 goto error_exit; 624 } 625 626 /* 627 * Check a few values (could do some more): 628 * - logical sector size: >= block size 629 * - number of sectors: <= size of partition 630 */ 631 if ((pmp->pm_BytesPerSec < GEMDOSFS_BSIZE) || 632 (pmp->pm_HugeSectors * 633 (pmp->pm_BytesPerSec / GEMDOSFS_BSIZE) > psize)) { 634 DPRINTF("consistency checks for GEMDOS"); 635 error = EINVAL; 636 goto error_exit; 637 } 638 /* 639 * XXX - Many parts of the msdosfs driver seem to assume that 640 * the number of bytes per logical sector (BytesPerSec) will 641 * always be the same as the number of bytes per disk block 642 * Let's pretend it is. 643 */ 644 BlkPerSec = pmp->pm_BytesPerSec / GEMDOSFS_BSIZE; 645 pmp->pm_BytesPerSec = GEMDOSFS_BSIZE; 646 pmp->pm_HugeSectors *= BlkPerSec; 647 pmp->pm_HiddenSects *= BlkPerSec; 648 pmp->pm_ResSectors *= BlkPerSec; 649 pmp->pm_Sectors *= BlkPerSec; 650 pmp->pm_FATsecs *= BlkPerSec; 651 SecPerClust *= BlkPerSec; 652 } 653 654 /* Check that fs has nonzero FAT size */ 655 if (pmp->pm_FATsecs == 0) { 656 DPRINTF("FATsecs is 0"); 657 error = EINVAL; 658 goto error_exit; 659 } 660 661 pmp->pm_fatblk = pmp->pm_ResSectors; 662 if (FAT32(pmp)) { 663 if (secsize < sizeof(*b710)) { 664 DPRINTF("710 bootsec %u\n", secsize); 665 error = EINVAL; 666 goto error_exit; 667 } 668 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 669 pmp->pm_firstcluster = pmp->pm_fatblk 670 + (pmp->pm_FATs * pmp->pm_FATsecs); 671 pmp->pm_fsinfo = getushort(b710->bpbFSInfo); 672 } else { 673 pmp->pm_rootdirblk = pmp->pm_fatblk + 674 (pmp->pm_FATs * pmp->pm_FATsecs); 675 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 676 + pmp->pm_BytesPerSec - 1) 677 / pmp->pm_BytesPerSec;/* in sectors */ 678 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 679 } 680 681 pmp->pm_nmbrofclusters = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 682 SecPerClust; 683 pmp->pm_maxcluster = pmp->pm_nmbrofclusters + 1; 684 pmp->pm_fatsize = pmp->pm_FATsecs * pmp->pm_BytesPerSec; 685 686 if (argp->flags & MSDOSFSMNT_GEMDOSFS) { 687 if (pmp->pm_nmbrofclusters <= (0xff0 - 2)) { 688 pmp->pm_fatmask = FAT12_MASK; 689 pmp->pm_fatmult = 3; 690 pmp->pm_fatdiv = 2; 691 } else { 692 pmp->pm_fatmask = FAT16_MASK; 693 pmp->pm_fatmult = 2; 694 pmp->pm_fatdiv = 1; 695 } 696 } else if (pmp->pm_fatmask == 0) { 697 if (pmp->pm_maxcluster 698 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 699 /* 700 * This will usually be a floppy disk. This size makes 701 * sure that one FAT entry will not be split across 702 * multiple blocks. 703 */ 704 pmp->pm_fatmask = FAT12_MASK; 705 pmp->pm_fatmult = 3; 706 pmp->pm_fatdiv = 2; 707 } else { 708 pmp->pm_fatmask = FAT16_MASK; 709 pmp->pm_fatmult = 2; 710 pmp->pm_fatdiv = 1; 711 } 712 } 713 if (FAT12(pmp)) 714 pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec; 715 else 716 pmp->pm_fatblocksize = MAXBSIZE; 717 718 pmp->pm_fatblocksec = pmp->pm_fatblocksize / pmp->pm_BytesPerSec; 719 pmp->pm_bnshift = ffs(pmp->pm_BytesPerSec) - 1; 720 721 /* 722 * Compute mask and shift value for isolating cluster relative byte 723 * offsets and cluster numbers from a file offset. 724 */ 725 pmp->pm_bpcluster = SecPerClust * pmp->pm_BytesPerSec; 726 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 727 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 728 729 /* 730 * Check for valid cluster size 731 * must be a power of 2 732 */ 733 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 734 DPRINTF("bpcluster %lu cnshift %lu", pmp->pm_bpcluster, 735 pmp->pm_cnshift); 736 error = EINVAL; 737 goto error_exit; 738 } 739 740 /* 741 * Cluster size must be within limit of MAXBSIZE. 742 * Many FAT filesystems will not have clusters larger than 743 * 32KiB due to limits in Windows versions before Vista. 744 */ 745 if (pmp->pm_bpcluster > MAXBSIZE) { 746 DPRINTF("bpcluster %lu > MAXBSIZE %d", 747 pmp->pm_bpcluster, MAXBSIZE); 748 error = EINVAL; 749 goto error_exit; 750 } 751 752 /* 753 * Release the bootsector buffer. 754 */ 755 brelse(bp, BC_AGE); 756 bp = NULL; 757 758 /* 759 * Check FSInfo. 760 */ 761 if (pmp->pm_fsinfo) { 762 struct fsinfo *fp; 763 const int rdsz = roundup(sizeof(*fp), pmp->pm_BytesPerSec); 764 765 /* 766 * XXX If the fsinfo block is stored on media with 767 * 2KB or larger sectors, is the fsinfo structure 768 * padded at the end or in the middle? 769 */ 770 if ((error = bread(devvp, de_bn2kb(pmp, pmp->pm_fsinfo), 771 rdsz, 0, &bp)) != 0) 772 goto error_exit; 773 fp = (struct fsinfo *)bp->b_data; 774 if (!memcmp(fp->fsisig1, "RRaA", 4) 775 && !memcmp(fp->fsisig2, "rrAa", 4) 776 && !memcmp(fp->fsisig3, "\0\0\125\252", 4) 777 && !memcmp(fp->fsisig4, "\0\0\125\252", 4)) 778 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 779 else 780 pmp->pm_fsinfo = 0; 781 brelse(bp, 0); 782 bp = NULL; 783 } 784 785 /* 786 * Check and validate (or perhaps invalidate?) the fsinfo structure? 787 * XXX 788 */ 789 if (pmp->pm_fsinfo) { 790 if ((pmp->pm_nxtfree == 0xffffffffUL) || 791 (pmp->pm_nxtfree > pmp->pm_maxcluster)) 792 pmp->pm_fsinfo = 0; 793 } 794 795 /* 796 * Allocate memory for the bitmap of allocated clusters, and then 797 * fill it in. 798 */ 799 pmp->pm_inusemap = malloc(((pmp->pm_maxcluster + N_INUSEBITS) 800 / N_INUSEBITS) 801 * sizeof(*pmp->pm_inusemap), 802 M_MSDOSFSFAT, M_WAITOK); 803 804 /* 805 * fillinusemap() needs pm_devvp. 806 */ 807 pmp->pm_dev = dev; 808 pmp->pm_devvp = devvp; 809 810 /* 811 * Have the inuse map filled in. 812 */ 813 if ((error = fillinusemap(pmp)) != 0) { 814 DPRINTF("fillinusemap %d", error); 815 goto error_exit; 816 } 817 818 /* 819 * If they want FAT updates to be synchronous then let them suffer 820 * the performance degradation in exchange for the on disk copy of 821 * the FAT being correct just about all the time. I suppose this 822 * would be a good thing to turn on if the kernel is still flakey. 823 */ 824 if (mp->mnt_flag & MNT_SYNCHRONOUS) 825 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 826 827 /* 828 * Finish up. 829 */ 830 if (ronly) 831 pmp->pm_flags |= MSDOSFSMNT_RONLY; 832 else 833 pmp->pm_fmod = 1; 834 mp->mnt_data = pmp; 835 mp->mnt_stat.f_fsidx.__fsid_val[0] = (long)dev; 836 mp->mnt_stat.f_fsidx.__fsid_val[1] = makefstype(MOUNT_MSDOS); 837 mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0]; 838 mp->mnt_stat.f_namemax = MSDOSFS_NAMEMAX(pmp); 839 mp->mnt_flag |= MNT_LOCAL; 840 mp->mnt_dev_bshift = pmp->pm_bnshift; 841 mp->mnt_fs_bshift = pmp->pm_cnshift; 842 843 /* 844 * If we ever do quotas for DOS filesystems this would be a place 845 * to fill in the info in the msdosfsmount structure. You dolt, 846 * quotas on dos filesystems make no sense because files have no 847 * owners on dos filesystems. of course there is some empty space 848 * in the directory entry where we could put uid's and gid's. 849 */ 850 851 spec_node_setmountedfs(devvp, mp); 852 853 return (0); 854 855 error_exit: 856 if (bp) 857 brelse(bp, BC_AGE); 858 if (pmp) { 859 if (pmp->pm_inusemap) 860 free(pmp->pm_inusemap, M_MSDOSFSFAT); 861 free(pmp, M_MSDOSFSMNT); 862 mp->mnt_data = NULL; 863 } 864 return (error); 865 } 866 867 int 868 msdosfs_start(struct mount *mp, int flags) 869 { 870 871 return (0); 872 } 873 874 /* 875 * Unmount the filesystem described by mp. 876 */ 877 int 878 msdosfs_unmount(struct mount *mp, int mntflags) 879 { 880 struct msdosfsmount *pmp; 881 int error, flags; 882 883 flags = 0; 884 if (mntflags & MNT_FORCE) 885 flags |= FORCECLOSE; 886 if ((error = vflush(mp, NULLVP, flags)) != 0) 887 return (error); 888 pmp = VFSTOMSDOSFS(mp); 889 if (pmp->pm_devvp->v_type != VBAD) 890 spec_node_setmountedfs(pmp->pm_devvp, NULL); 891 #ifdef MSDOSFS_DEBUG 892 { 893 struct vnode *vp = pmp->pm_devvp; 894 895 printf("msdosfs_umount(): just before calling VOP_CLOSE()\n"); 896 printf("flag %08x, usecount %d, writecount %d, holdcnt %d\n", 897 vp->v_vflag | vp->v_iflag | vp->v_uflag, vp->v_usecount, 898 vp->v_writecount, vp->v_holdcnt); 899 printf("mount %p, op %p\n", 900 vp->v_mount, vp->v_op); 901 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %d, type %d\n", 902 vp->v_cleanblkhd.lh_first, 903 vp->v_dirtyblkhd.lh_first, 904 vp->v_numoutput, vp->v_type); 905 printf("union %p, tag %d, data[0] %08x, data[1] %08x\n", 906 vp->v_socket, vp->v_tag, 907 ((u_int *)vp->v_data)[0], 908 ((u_int *)vp->v_data)[1]); 909 } 910 #endif 911 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 912 (void) VOP_CLOSE(pmp->pm_devvp, 913 pmp->pm_flags & MSDOSFSMNT_RONLY ? FREAD : FREAD|FWRITE, NOCRED); 914 vput(pmp->pm_devvp); 915 msdosfs_fh_destroy(pmp); 916 free(pmp->pm_inusemap, M_MSDOSFSFAT); 917 free(pmp, M_MSDOSFSMNT); 918 mp->mnt_data = NULL; 919 mp->mnt_flag &= ~MNT_LOCAL; 920 return (0); 921 } 922 923 int 924 msdosfs_root(struct mount *mp, struct vnode **vpp) 925 { 926 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 927 int error; 928 929 #ifdef MSDOSFS_DEBUG 930 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 931 #endif 932 if ((error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, vpp)) != 0) 933 return error; 934 error = vn_lock(*vpp, LK_EXCLUSIVE); 935 if (error) { 936 vrele(*vpp); 937 *vpp = NULL; 938 return error; 939 } 940 return 0; 941 } 942 943 int 944 msdosfs_statvfs(struct mount *mp, struct statvfs *sbp) 945 { 946 struct msdosfsmount *pmp; 947 948 pmp = VFSTOMSDOSFS(mp); 949 sbp->f_bsize = pmp->pm_bpcluster; 950 sbp->f_frsize = sbp->f_bsize; 951 sbp->f_iosize = pmp->pm_bpcluster; 952 sbp->f_blocks = pmp->pm_nmbrofclusters; 953 sbp->f_bfree = pmp->pm_freeclustercount; 954 sbp->f_bavail = pmp->pm_freeclustercount; 955 sbp->f_bresvd = 0; 956 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 957 sbp->f_ffree = 0; /* what to put in here? */ 958 sbp->f_favail = 0; /* what to put in here? */ 959 sbp->f_fresvd = 0; 960 copy_statvfs_info(sbp, mp); 961 return (0); 962 } 963 964 struct msdosfs_sync_ctx { 965 int waitfor; 966 }; 967 968 static bool 969 msdosfs_sync_selector(void *cl, struct vnode *vp) 970 { 971 struct msdosfs_sync_ctx *c = cl; 972 struct denode *dep; 973 974 KASSERT(mutex_owned(vp->v_interlock)); 975 976 dep = VTODE(vp); 977 if (c->waitfor == MNT_LAZY || vp->v_type == VNON || 978 dep == NULL || (((dep->de_flag & 979 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0) && 980 (LIST_EMPTY(&vp->v_dirtyblkhd) && 981 UVM_OBJ_IS_CLEAN(&vp->v_uobj)))) 982 return false; 983 return true; 984 } 985 986 int 987 msdosfs_sync(struct mount *mp, int waitfor, kauth_cred_t cred) 988 { 989 struct vnode *vp; 990 struct vnode_iterator *marker; 991 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 992 int error, allerror = 0; 993 struct msdosfs_sync_ctx ctx; 994 995 /* 996 * If we ever switch to not updating all of the FATs all the time, 997 * this would be the place to update them from the first one. 998 */ 999 if (pmp->pm_fmod != 0) { 1000 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 1001 panic("msdosfs_sync: rofs mod"); 1002 else { 1003 /* update FATs here */ 1004 } 1005 } 1006 /* 1007 * Write back each (modified) denode. 1008 */ 1009 vfs_vnode_iterator_init(mp, &marker); 1010 ctx.waitfor = waitfor; 1011 while ((vp = vfs_vnode_iterator_next(marker, msdosfs_sync_selector, 1012 &ctx))) 1013 { 1014 error = vn_lock(vp, LK_EXCLUSIVE); 1015 if (error) { 1016 vrele(vp); 1017 continue; 1018 } 1019 if ((error = VOP_FSYNC(vp, cred, 1020 waitfor == MNT_WAIT ? FSYNC_WAIT : 0, 0, 0)) != 0) 1021 allerror = error; 1022 vput(vp); 1023 } 1024 vfs_vnode_iterator_destroy(marker); 1025 1026 /* 1027 * Force stale file system control information to be flushed. 1028 */ 1029 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 1030 if ((error = VOP_FSYNC(pmp->pm_devvp, cred, 1031 waitfor == MNT_WAIT ? FSYNC_WAIT : 0, 0, 0)) != 0) 1032 allerror = error; 1033 VOP_UNLOCK(pmp->pm_devvp); 1034 return (allerror); 1035 } 1036 1037 int 1038 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp) 1039 { 1040 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 1041 struct defid defh; 1042 uint32_t gen; 1043 int error; 1044 1045 if (fhp->fid_len != sizeof(struct defid)) { 1046 DPRINTF("fid_len %d %zd", fhp->fid_len, sizeof(struct defid)); 1047 return EINVAL; 1048 } 1049 memcpy(&defh, fhp, sizeof(defh)); 1050 error = msdosfs_fh_lookup(pmp, defh.defid_dirclust, defh.defid_dirofs, 1051 &gen); 1052 if (error == 0 && gen != defh.defid_gen) 1053 error = ESTALE; 1054 if (error) { 1055 *vpp = NULLVP; 1056 return error; 1057 } 1058 error = deget(pmp, defh.defid_dirclust, defh.defid_dirofs, vpp); 1059 if (error) { 1060 DPRINTF("deget %d", error); 1061 *vpp = NULLVP; 1062 return error; 1063 } 1064 error = vn_lock(*vpp, LK_EXCLUSIVE); 1065 if (error) { 1066 vrele(*vpp); 1067 *vpp = NULLVP; 1068 return error; 1069 } 1070 return 0; 1071 } 1072 1073 int 1074 msdosfs_vptofh(struct vnode *vp, struct fid *fhp, size_t *fh_size) 1075 { 1076 struct msdosfsmount *pmp = VFSTOMSDOSFS(vp->v_mount); 1077 struct denode *dep; 1078 struct defid defh; 1079 int error; 1080 1081 if (*fh_size < sizeof(struct defid)) { 1082 *fh_size = sizeof(struct defid); 1083 return E2BIG; 1084 } 1085 *fh_size = sizeof(struct defid); 1086 dep = VTODE(vp); 1087 memset(&defh, 0, sizeof(defh)); 1088 defh.defid_len = sizeof(struct defid); 1089 defh.defid_dirclust = dep->de_dirclust; 1090 defh.defid_dirofs = dep->de_diroffset; 1091 error = msdosfs_fh_enter(pmp, dep->de_dirclust, dep->de_diroffset, 1092 &defh.defid_gen); 1093 if (error == 0) 1094 memcpy(fhp, &defh, sizeof(defh)); 1095 return error; 1096 } 1097 1098 int 1099 msdosfs_vget(struct mount *mp, ino_t ino, 1100 struct vnode **vpp) 1101 { 1102 1103 return (EOPNOTSUPP); 1104 } 1105
Indexes created Fri Sep 26 08:10:20 GMT 2025