msdosfs_vfsops.c revision 1.118.2.1
1 /* $NetBSD: msdosfs_vfsops.c,v 1.118.2.1 2016/07/20 23:47:56 pgoyette 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 1.118.2.1 2016/07/20 23:47:56 pgoyette 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/fstrans.h> 73 #include <sys/ioctl.h> 74 #include <sys/malloc.h> 75 #include <sys/dirent.h> 76 #include <sys/stat.h> 77 #include <sys/conf.h> 78 #include <sys/kauth.h> 79 #include <sys/module.h> 80 81 #include <fs/msdosfs/bpb.h> 82 #include <fs/msdosfs/bootsect.h> 83 #include <fs/msdosfs/direntry.h> 84 #include <fs/msdosfs/denode.h> 85 #include <fs/msdosfs/msdosfsmount.h> 86 #include <fs/msdosfs/fat.h> 87 88 MODULE(MODULE_CLASS_VFS, msdos, NULL); 89 90 #ifdef MSDOSFS_DEBUG 91 #define DPRINTF(fmt, ...) uprintf("%s(): " fmt "\n", __func__, ##__VA_ARGS__) 92 #else 93 #define DPRINTF(fmt, ...) 94 #endif 95 96 #define GEMDOSFS_BSIZE 512 97 98 #define MSDOSFS_NAMEMAX(pmp) \ 99 (pmp)->pm_flags & MSDOSFSMNT_LONGNAME ? WIN_MAXLEN : 12 100 101 int msdosfs_mountfs(struct vnode *, struct mount *, struct lwp *, 102 struct msdosfs_args *); 103 104 static int update_mp(struct mount *, struct msdosfs_args *); 105 106 MALLOC_JUSTDEFINE(M_MSDOSFSMNT, "MSDOSFS mount", "MSDOS FS mount structure"); 107 MALLOC_JUSTDEFINE(M_MSDOSFSFAT, "MSDOSFS FAT", "MSDOS FS FAT table"); 108 MALLOC_JUSTDEFINE(M_MSDOSFSTMP, "MSDOSFS temp", "MSDOS FS temp. structures"); 109 110 static struct sysctllog *msdosfs_sysctl_log; 111 112 extern const struct vnodeopv_desc msdosfs_vnodeop_opv_desc; 113 114 const struct vnodeopv_desc * const msdosfs_vnodeopv_descs[] = { 115 &msdosfs_vnodeop_opv_desc, 116 NULL, 117 }; 118 119 struct vfsops msdosfs_vfsops = { 120 .vfs_name = MOUNT_MSDOS, 121 .vfs_min_mount_data = sizeof (struct msdosfs_args), 122 .vfs_mount = msdosfs_mount, 123 .vfs_start = msdosfs_start, 124 .vfs_unmount = msdosfs_unmount, 125 .vfs_root = msdosfs_root, 126 .vfs_quotactl = (void *)eopnotsupp, 127 .vfs_statvfs = msdosfs_statvfs, 128 .vfs_sync = msdosfs_sync, 129 .vfs_vget = msdosfs_vget, 130 .vfs_loadvnode = msdosfs_loadvnode, 131 .vfs_fhtovp = msdosfs_fhtovp, 132 .vfs_vptofh = msdosfs_vptofh, 133 .vfs_init = msdosfs_init, 134 .vfs_reinit = msdosfs_reinit, 135 .vfs_done = msdosfs_done, 136 .vfs_mountroot = msdosfs_mountroot, 137 .vfs_snapshot = (void *)eopnotsupp, 138 .vfs_extattrctl = vfs_stdextattrctl, 139 .vfs_suspendctl = msdosfs_suspendctl, 140 .vfs_renamelock_enter = genfs_renamelock_enter, 141 .vfs_renamelock_exit = genfs_renamelock_exit, 142 .vfs_fsync = (void *)eopnotsupp, 143 .vfs_opv_descs = msdosfs_vnodeopv_descs 144 }; 145 146 static int 147 msdos_modcmd(modcmd_t cmd, void *arg) 148 { 149 int error; 150 151 switch (cmd) { 152 case MODULE_CMD_INIT: 153 error = vfs_attach(&msdosfs_vfsops); 154 if (error != 0) 155 break; 156 sysctl_createv(&msdosfs_sysctl_log, 0, NULL, NULL, 157 CTLFLAG_PERMANENT, 158 CTLTYPE_NODE, "msdosfs", 159 SYSCTL_DESCR("MS-DOS file system"), 160 NULL, 0, NULL, 0, 161 CTL_VFS, 4, CTL_EOL); 162 /* 163 * XXX the "4" above could be dynamic, thereby eliminating one 164 * more instance of the "number to vfs" mapping problem, but 165 * "4" is the order as taken from sys/mount.h 166 */ 167 break; 168 case MODULE_CMD_FINI: 169 error = vfs_detach(&msdosfs_vfsops); 170 if (error != 0) 171 break; 172 sysctl_teardown(&msdosfs_sysctl_log); 173 break; 174 default: 175 error = ENOTTY; 176 break; 177 } 178 179 return (error); 180 } 181 182 static int 183 update_mp(struct mount *mp, struct msdosfs_args *argp) 184 { 185 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 186 int error; 187 188 pmp->pm_gid = argp->gid; 189 pmp->pm_uid = argp->uid; 190 pmp->pm_mask = argp->mask & ALLPERMS; 191 pmp->pm_dirmask = argp->dirmask & ALLPERMS; 192 pmp->pm_gmtoff = argp->gmtoff; 193 pmp->pm_flags |= argp->flags & MSDOSFSMNT_MNTOPT; 194 195 /* 196 * GEMDOS knows nothing about win95 long filenames 197 */ 198 if (pmp->pm_flags & MSDOSFSMNT_GEMDOSFS) 199 pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 200 201 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 202 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 203 else if (!(pmp->pm_flags & 204 (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) { 205 struct vnode *rtvp; 206 207 /* 208 * Try to divine whether to support Win'95 long filenames 209 */ 210 if (FAT32(pmp)) 211 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 212 else { 213 if ((error = msdosfs_root(mp, &rtvp)) != 0) 214 return error; 215 pmp->pm_flags |= findwin95(VTODE(rtvp)) 216 ? MSDOSFSMNT_LONGNAME 217 : MSDOSFSMNT_SHORTNAME; 218 vput(rtvp); 219 } 220 } 221 222 mp->mnt_stat.f_namemax = MSDOSFS_NAMEMAX(pmp); 223 224 return 0; 225 } 226 227 int 228 msdosfs_mountroot(void) 229 { 230 struct mount *mp; 231 struct lwp *l = curlwp; /* XXX */ 232 int error; 233 struct msdosfs_args args; 234 235 if (device_class(root_device) != DV_DISK) 236 return (ENODEV); 237 238 if ((error = vfs_rootmountalloc(MOUNT_MSDOS, "root_device", &mp))) { 239 vrele(rootvp); 240 return (error); 241 } 242 243 args.flags = MSDOSFSMNT_VERSIONED; 244 args.uid = 0; 245 args.gid = 0; 246 args.mask = 0777; 247 args.version = MSDOSFSMNT_VERSION; 248 args.dirmask = 0777; 249 250 if ((error = msdosfs_mountfs(rootvp, mp, l, &args)) != 0) { 251 vfs_unbusy(mp, false, NULL); 252 vfs_destroy(mp); 253 return (error); 254 } 255 256 if ((error = update_mp(mp, &args)) != 0) { 257 (void)msdosfs_unmount(mp, 0); 258 vfs_unbusy(mp, false, NULL); 259 vfs_destroy(mp); 260 vrele(rootvp); 261 return (error); 262 } 263 264 mountlist_append(mp); 265 (void)msdosfs_statvfs(mp, &mp->mnt_stat); 266 vfs_unbusy(mp, false, NULL); 267 return (0); 268 } 269 270 /* 271 * mp - path - addr in user space of mount point (ie /usr or whatever) 272 * data - addr in user space of mount params including the name of the block 273 * special file to treat as a filesystem. 274 */ 275 int 276 msdosfs_mount(struct mount *mp, const char *path, void *data, size_t *data_len) 277 { 278 struct lwp *l = curlwp; 279 struct vnode *devvp; /* vnode for blk device to mount */ 280 struct msdosfs_args *args = data; /* holds data from mount request */ 281 /* msdosfs specific mount control block */ 282 struct msdosfsmount *pmp = NULL; 283 int error, flags; 284 mode_t accessmode; 285 const struct bdevsw *bdev; 286 287 if (args == NULL) 288 return EINVAL; 289 if (*data_len < sizeof *args) 290 return EINVAL; 291 292 if (mp->mnt_flag & MNT_GETARGS) { 293 pmp = VFSTOMSDOSFS(mp); 294 if (pmp == NULL) 295 return EIO; 296 args->fspec = NULL; 297 args->uid = pmp->pm_uid; 298 args->gid = pmp->pm_gid; 299 args->mask = pmp->pm_mask; 300 args->flags = pmp->pm_flags; 301 args->version = MSDOSFSMNT_VERSION; 302 args->dirmask = pmp->pm_dirmask; 303 args->gmtoff = pmp->pm_gmtoff; 304 *data_len = sizeof *args; 305 return 0; 306 } 307 308 /* 309 * If not versioned (i.e. using old mount_msdos(8)), fill in 310 * the additional structure items with suitable defaults. 311 */ 312 if ((args->flags & MSDOSFSMNT_VERSIONED) == 0) { 313 args->version = 1; 314 args->dirmask = args->mask; 315 } 316 317 /* 318 * Reset GMT offset for pre-v3 mount structure args. 319 */ 320 if (args->version < 3) 321 args->gmtoff = 0; 322 323 /* 324 * If updating, check whether changing from read-only to 325 * read/write; if there is no device name, that's all we do. 326 */ 327 if (mp->mnt_flag & MNT_UPDATE) { 328 pmp = VFSTOMSDOSFS(mp); 329 error = 0; 330 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 331 (mp->mnt_flag & MNT_RDONLY)) { 332 flags = WRITECLOSE; 333 if (mp->mnt_flag & MNT_FORCE) 334 flags |= FORCECLOSE; 335 error = vflush(mp, NULLVP, flags); 336 } 337 if (!error && (mp->mnt_flag & MNT_RELOAD)) 338 /* not yet implemented */ 339 error = EOPNOTSUPP; 340 if (error) { 341 DPRINTF("vflush %d", error); 342 return (error); 343 } 344 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 345 (mp->mnt_iflag & IMNT_WANTRDWR)) { 346 /* 347 * If upgrade to read-write by non-root, then verify 348 * that user has necessary permissions on the device. 349 * 350 * Permission to update a mount is checked higher, so 351 * here we presume updating the mount is okay (for 352 * example, as far as securelevel goes) which leaves us 353 * with the normal check. 354 */ 355 devvp = pmp->pm_devvp; 356 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 357 error = kauth_authorize_system(l->l_cred, 358 KAUTH_SYSTEM_MOUNT, KAUTH_REQ_SYSTEM_MOUNT_DEVICE, 359 mp, devvp, KAUTH_ARG(VREAD | VWRITE)); 360 VOP_UNLOCK(devvp); 361 DPRINTF("KAUTH_REQ_SYSTEM_MOUNT_DEVICE %d", error); 362 if (error) 363 return (error); 364 365 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 366 } 367 if (args->fspec == NULL) { 368 DPRINTF("missing fspec"); 369 return EINVAL; 370 } 371 } 372 /* 373 * Not an update, or updating the name: look up the name 374 * and verify that it refers to a sensible block device. 375 */ 376 error = namei_simple_user(args->fspec, 377 NSM_FOLLOW_NOEMULROOT, &devvp); 378 if (error != 0) { 379 DPRINTF("namei %d", error); 380 return (error); 381 } 382 383 if (devvp->v_type != VBLK) { 384 DPRINTF("not block"); 385 vrele(devvp); 386 return (ENOTBLK); 387 } 388 if ((bdev = bdevsw_lookup_acquire(devvp->v_rdev)) == NULL) { 389 DPRINTF("no block switch"); 390 vrele(devvp); 391 return (ENXIO); 392 } 393 /* 394 * If mount by non-root, then verify that user has necessary 395 * permissions on the device. 396 */ 397 accessmode = VREAD; 398 if ((mp->mnt_flag & MNT_RDONLY) == 0) 399 accessmode |= VWRITE; 400 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 401 error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MOUNT, 402 KAUTH_REQ_SYSTEM_MOUNT_DEVICE, mp, devvp, KAUTH_ARG(accessmode)); 403 VOP_UNLOCK(devvp); 404 if (error) { 405 DPRINTF("KAUTH_REQ_SYSTEM_MOUNT_DEVICE %d", error); 406 bdevsw_release(bdev); 407 vrele(devvp); 408 return (error); 409 } 410 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 411 int xflags; 412 413 if (mp->mnt_flag & MNT_RDONLY) 414 xflags = FREAD; 415 else 416 xflags = FREAD|FWRITE; 417 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 418 error = VOP_OPEN(devvp, xflags, FSCRED); 419 VOP_UNLOCK(devvp); 420 if (error) { 421 DPRINTF("VOP_OPEN %d", error); 422 goto fail; 423 } 424 error = msdosfs_mountfs(devvp, mp, l, args); 425 if (error) { 426 DPRINTF("msdosfs_mountfs %d", error); 427 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 428 (void) VOP_CLOSE(devvp, xflags, NOCRED); 429 VOP_UNLOCK(devvp); 430 goto fail; 431 } 432 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 433 pmp = VFSTOMSDOSFS(mp); 434 #endif 435 } else { 436 vrele(devvp); 437 if (devvp != pmp->pm_devvp) { 438 DPRINTF("devvp %p pmp %p", devvp, pmp->pm_devvp); 439 bdevsw_release(bdev); 440 return (EINVAL); /* needs translation */ 441 } 442 } 443 if ((error = update_mp(mp, args)) != 0) { 444 msdosfs_unmount(mp, MNT_FORCE); 445 DPRINTF("update_mp %d", error); 446 bdevsw_release(bdev); 447 return error; 448 } 449 450 #ifdef MSDOSFS_DEBUG 451 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 452 #endif 453 error = set_statvfs_info(path, UIO_USERSPACE, args->fspec, 454 UIO_USERSPACE, mp->mnt_op->vfs_name, mp, l); 455 bdevsw_release(bdev); 456 return error; 457 458 fail: 459 bdevsw_release(bdev); 460 vrele(devvp); 461 return (error); 462 } 463 464 int 465 msdosfs_mountfs(struct vnode *devvp, struct mount *mp, struct lwp *l, struct msdosfs_args *argp) 466 { 467 struct msdosfsmount *pmp; 468 struct buf *bp; 469 dev_t dev = devvp->v_rdev; 470 union bootsector *bsp; 471 struct byte_bpb33 *b33; 472 struct byte_bpb50 *b50; 473 struct byte_bpb710 *b710; 474 uint8_t SecPerClust; 475 int ronly, error, BlkPerSec; 476 uint64_t psize; 477 unsigned secsize; 478 479 /* Flush out any old buffers remaining from a previous use. */ 480 if ((error = vinvalbuf(devvp, V_SAVE, l->l_cred, l, 0, 0)) != 0) 481 return (error); 482 483 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 484 485 bp = NULL; /* both used in error_exit */ 486 pmp = NULL; 487 488 error = fstrans_mount(mp); 489 if (error) 490 goto error_exit; 491 492 error = getdisksize(devvp, &psize, &secsize); 493 if (error) { 494 if (argp->flags & MSDOSFSMNT_GEMDOSFS) 495 goto error_exit; 496 497 /* ok, so it failed. we most likely don't need the info */ 498 secsize = DEV_BSIZE; 499 psize = 0; 500 error = 0; 501 } 502 if (secsize < DEV_BSIZE) { 503 DPRINTF("Invalid block secsize (%d < DEV_BSIZE)", secsize); 504 error = EINVAL; 505 goto error_exit; 506 } 507 508 if (argp->flags & MSDOSFSMNT_GEMDOSFS) { 509 if (secsize != GEMDOSFS_BSIZE) { 510 DPRINTF("Invalid block secsize %d for GEMDOS", secsize); 511 error = EINVAL; 512 goto error_exit; 513 } 514 } 515 516 /* 517 * Read the boot sector of the filesystem, and then check the 518 * boot signature. If not a dos boot sector then error out. 519 */ 520 if (secsize < sizeof(*b50)) { 521 DPRINTF("50 bootsec %u\n", secsize); 522 error = EINVAL; 523 goto error_exit; 524 } 525 if ((error = bread(devvp, 0, secsize, 0, &bp)) != 0) 526 goto error_exit; 527 bsp = (union bootsector *)bp->b_data; 528 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 529 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 530 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 531 532 if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) { 533 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 534 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 535 DPRINTF("bootsig0 %d bootsig1 %d", 536 bsp->bs50.bsBootSectSig0, 537 bsp->bs50.bsBootSectSig1); 538 error = EINVAL; 539 goto error_exit; 540 } 541 } 542 543 pmp = malloc(sizeof(*pmp), M_MSDOSFSMNT, M_WAITOK|M_ZERO); 544 pmp->pm_mountp = mp; 545 546 /* 547 * Compute several useful quantities from the bpb in the 548 * bootsector. Copy in the dos 5 variant of the bpb then fix up 549 * the fields that are different between dos 5 and dos 3.3. 550 */ 551 SecPerClust = b50->bpbSecPerClust; 552 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 553 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 554 pmp->pm_FATs = b50->bpbFATs; 555 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 556 pmp->pm_Sectors = getushort(b50->bpbSectors); 557 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 558 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 559 pmp->pm_Heads = getushort(b50->bpbHeads); 560 pmp->pm_Media = b50->bpbMedia; 561 562 if (pmp->pm_Sectors == 0) { 563 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 564 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 565 } else { 566 if (secsize < sizeof(*b33)) { 567 DPRINTF("33 bootsec %u\n", secsize); 568 error = EINVAL; 569 goto error_exit; 570 } 571 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 572 pmp->pm_HugeSectors = pmp->pm_Sectors; 573 } 574 575 /* 576 * Sanity checks, from the FAT specification: 577 * - sectors per cluster: >= 1, power of 2 578 * - logical sector size: >= 1, power of 2 579 * - cluster size: <= max FS block size 580 * - number of sectors: >= 1 581 */ 582 if ((SecPerClust == 0) || !powerof2(SecPerClust) || 583 (pmp->pm_BytesPerSec == 0) || !powerof2(pmp->pm_BytesPerSec) || 584 (SecPerClust * pmp->pm_BytesPerSec > MAXBSIZE) || 585 (pmp->pm_HugeSectors == 0)) { 586 DPRINTF("consistency checks"); 587 error = EINVAL; 588 goto error_exit; 589 } 590 591 if (!(argp->flags & MSDOSFSMNT_GEMDOSFS) && 592 (pmp->pm_SecPerTrack > 63)) { 593 DPRINTF("SecPerTrack %d", pmp->pm_SecPerTrack); 594 error = EINVAL; 595 goto error_exit; 596 } 597 598 if (pmp->pm_RootDirEnts == 0) { 599 if (secsize < sizeof(*b710)) { 600 DPRINTF("710 bootsec %u\n", secsize); 601 error = EINVAL; 602 goto error_exit; 603 } 604 unsigned short FSVers = getushort(b710->bpbFSVers); 605 unsigned short ExtFlags = getushort(b710->bpbExtFlags); 606 /* 607 * Some say that bsBootSectSig[23] must be zero, but 608 * Windows does not require this and some digital cameras 609 * do not set these to zero. Therefore, do not insist. 610 */ 611 if (pmp->pm_Sectors || pmp->pm_FATsecs || FSVers) { 612 DPRINTF("Sectors %d FATsecs %lu FSVers %d", 613 pmp->pm_Sectors, pmp->pm_FATsecs, FSVers); 614 error = EINVAL; 615 goto error_exit; 616 } 617 pmp->pm_fatmask = FAT32_MASK; 618 pmp->pm_fatmult = 4; 619 pmp->pm_fatdiv = 1; 620 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 621 622 /* Mirroring is enabled if the FATMIRROR bit is not set. */ 623 if ((ExtFlags & FATMIRROR) == 0) 624 pmp->pm_flags |= MSDOSFS_FATMIRROR; 625 else 626 pmp->pm_curfat = ExtFlags & FATNUM; 627 } else 628 pmp->pm_flags |= MSDOSFS_FATMIRROR; 629 630 if (argp->flags & MSDOSFSMNT_GEMDOSFS) { 631 if (FAT32(pmp)) { 632 /* GEMDOS doesn't know FAT32. */ 633 DPRINTF("FAT32 for GEMDOS"); 634 error = EINVAL; 635 goto error_exit; 636 } 637 638 /* 639 * Check a few values (could do some more): 640 * - logical sector size: >= block size 641 * - number of sectors: <= size of partition 642 */ 643 if ((pmp->pm_BytesPerSec < GEMDOSFS_BSIZE) || 644 (pmp->pm_HugeSectors * 645 (pmp->pm_BytesPerSec / GEMDOSFS_BSIZE) > psize)) { 646 DPRINTF("consistency checks for GEMDOS"); 647 error = EINVAL; 648 goto error_exit; 649 } 650 /* 651 * XXX - Many parts of the msdosfs driver seem to assume that 652 * the number of bytes per logical sector (BytesPerSec) will 653 * always be the same as the number of bytes per disk block 654 * Let's pretend it is. 655 */ 656 BlkPerSec = pmp->pm_BytesPerSec / GEMDOSFS_BSIZE; 657 pmp->pm_BytesPerSec = GEMDOSFS_BSIZE; 658 pmp->pm_HugeSectors *= BlkPerSec; 659 pmp->pm_HiddenSects *= BlkPerSec; 660 pmp->pm_ResSectors *= BlkPerSec; 661 pmp->pm_Sectors *= BlkPerSec; 662 pmp->pm_FATsecs *= BlkPerSec; 663 SecPerClust *= BlkPerSec; 664 } 665 666 /* Check that fs has nonzero FAT size */ 667 if (pmp->pm_FATsecs == 0) { 668 DPRINTF("FATsecs is 0"); 669 error = EINVAL; 670 goto error_exit; 671 } 672 673 pmp->pm_fatblk = pmp->pm_ResSectors; 674 if (FAT32(pmp)) { 675 if (secsize < sizeof(*b710)) { 676 DPRINTF("710 bootsec %u\n", secsize); 677 error = EINVAL; 678 goto error_exit; 679 } 680 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 681 pmp->pm_firstcluster = pmp->pm_fatblk 682 + (pmp->pm_FATs * pmp->pm_FATsecs); 683 pmp->pm_fsinfo = getushort(b710->bpbFSInfo); 684 } else { 685 pmp->pm_rootdirblk = pmp->pm_fatblk + 686 (pmp->pm_FATs * pmp->pm_FATsecs); 687 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 688 + pmp->pm_BytesPerSec - 1) 689 / pmp->pm_BytesPerSec;/* in sectors */ 690 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 691 } 692 693 pmp->pm_nmbrofclusters = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 694 SecPerClust; 695 pmp->pm_maxcluster = pmp->pm_nmbrofclusters + 1; 696 pmp->pm_fatsize = pmp->pm_FATsecs * pmp->pm_BytesPerSec; 697 698 if (argp->flags & MSDOSFSMNT_GEMDOSFS) { 699 if (pmp->pm_nmbrofclusters <= (0xff0 - 2)) { 700 pmp->pm_fatmask = FAT12_MASK; 701 pmp->pm_fatmult = 3; 702 pmp->pm_fatdiv = 2; 703 } else { 704 pmp->pm_fatmask = FAT16_MASK; 705 pmp->pm_fatmult = 2; 706 pmp->pm_fatdiv = 1; 707 } 708 } else if (pmp->pm_fatmask == 0) { 709 if (pmp->pm_maxcluster 710 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 711 /* 712 * This will usually be a floppy disk. This size makes 713 * sure that one FAT entry will not be split across 714 * multiple blocks. 715 */ 716 pmp->pm_fatmask = FAT12_MASK; 717 pmp->pm_fatmult = 3; 718 pmp->pm_fatdiv = 2; 719 } else { 720 pmp->pm_fatmask = FAT16_MASK; 721 pmp->pm_fatmult = 2; 722 pmp->pm_fatdiv = 1; 723 } 724 } 725 if (FAT12(pmp)) 726 pmp->pm_fatblocksize = 3 * pmp->pm_BytesPerSec; 727 else 728 pmp->pm_fatblocksize = MAXBSIZE; 729 730 pmp->pm_fatblocksec = pmp->pm_fatblocksize / pmp->pm_BytesPerSec; 731 pmp->pm_bnshift = ffs(pmp->pm_BytesPerSec) - 1; 732 733 /* 734 * Compute mask and shift value for isolating cluster relative byte 735 * offsets and cluster numbers from a file offset. 736 */ 737 pmp->pm_bpcluster = SecPerClust * pmp->pm_BytesPerSec; 738 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 739 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 740 741 /* 742 * Check for valid cluster size 743 * must be a power of 2 744 */ 745 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 746 DPRINTF("bpcluster %lu cnshift %lu", pmp->pm_bpcluster, 747 pmp->pm_cnshift); 748 error = EINVAL; 749 goto error_exit; 750 } 751 752 /* 753 * Cluster size must be within limit of MAXBSIZE. 754 * Many FAT filesystems will not have clusters larger than 755 * 32KiB due to limits in Windows versions before Vista. 756 */ 757 if (pmp->pm_bpcluster > MAXBSIZE) { 758 DPRINTF("bpcluster %lu > MAXBSIZE %d", 759 pmp->pm_bpcluster, MAXBSIZE); 760 error = EINVAL; 761 goto error_exit; 762 } 763 764 /* 765 * Release the bootsector buffer. 766 */ 767 brelse(bp, BC_AGE); 768 bp = NULL; 769 770 /* 771 * Check FSInfo. 772 */ 773 if (pmp->pm_fsinfo) { 774 struct fsinfo *fp; 775 const int rdsz = roundup(sizeof(*fp), pmp->pm_BytesPerSec); 776 777 /* 778 * XXX If the fsinfo block is stored on media with 779 * 2KB or larger sectors, is the fsinfo structure 780 * padded at the end or in the middle? 781 */ 782 if ((error = bread(devvp, de_bn2kb(pmp, pmp->pm_fsinfo), 783 rdsz, 0, &bp)) != 0) 784 goto error_exit; 785 fp = (struct fsinfo *)bp->b_data; 786 if (!memcmp(fp->fsisig1, "RRaA", 4) 787 && !memcmp(fp->fsisig2, "rrAa", 4) 788 && !memcmp(fp->fsisig3, "\0\0\125\252", 4) 789 && !memcmp(fp->fsisig4, "\0\0\125\252", 4)) 790 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 791 else 792 pmp->pm_fsinfo = 0; 793 brelse(bp, 0); 794 bp = NULL; 795 } 796 797 /* 798 * Check and validate (or perhaps invalidate?) the fsinfo structure? 799 * XXX 800 */ 801 if (pmp->pm_fsinfo) { 802 if ((pmp->pm_nxtfree == 0xffffffffUL) || 803 (pmp->pm_nxtfree > pmp->pm_maxcluster)) 804 pmp->pm_fsinfo = 0; 805 } 806 807 /* 808 * Allocate memory for the bitmap of allocated clusters, and then 809 * fill it in. 810 */ 811 pmp->pm_inusemap = malloc(((pmp->pm_maxcluster + N_INUSEBITS) 812 / N_INUSEBITS) 813 * sizeof(*pmp->pm_inusemap), 814 M_MSDOSFSFAT, M_WAITOK); 815 816 /* 817 * fillinusemap() needs pm_devvp. 818 */ 819 pmp->pm_dev = dev; 820 pmp->pm_devvp = devvp; 821 822 /* 823 * Have the inuse map filled in. 824 */ 825 if ((error = fillinusemap(pmp)) != 0) { 826 DPRINTF("fillinusemap %d", error); 827 goto error_exit; 828 } 829 830 /* 831 * If they want FAT updates to be synchronous then let them suffer 832 * the performance degradation in exchange for the on disk copy of 833 * the FAT being correct just about all the time. I suppose this 834 * would be a good thing to turn on if the kernel is still flakey. 835 */ 836 if (mp->mnt_flag & MNT_SYNCHRONOUS) 837 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 838 839 /* 840 * Finish up. 841 */ 842 if (ronly) 843 pmp->pm_flags |= MSDOSFSMNT_RONLY; 844 else 845 pmp->pm_fmod = 1; 846 mp->mnt_data = pmp; 847 mp->mnt_stat.f_fsidx.__fsid_val[0] = (long)dev; 848 mp->mnt_stat.f_fsidx.__fsid_val[1] = makefstype(MOUNT_MSDOS); 849 mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0]; 850 mp->mnt_stat.f_namemax = MSDOSFS_NAMEMAX(pmp); 851 mp->mnt_flag |= MNT_LOCAL; 852 mp->mnt_dev_bshift = pmp->pm_bnshift; 853 mp->mnt_fs_bshift = pmp->pm_cnshift; 854 855 /* 856 * If we ever do quotas for DOS filesystems this would be a place 857 * to fill in the info in the msdosfsmount structure. You dolt, 858 * quotas on dos filesystems make no sense because files have no 859 * owners on dos filesystems. of course there is some empty space 860 * in the directory entry where we could put uid's and gid's. 861 */ 862 863 spec_node_setmountedfs(devvp, mp); 864 865 return (0); 866 867 error_exit: 868 fstrans_unmount(mp); 869 if (bp) 870 brelse(bp, BC_AGE); 871 if (pmp) { 872 if (pmp->pm_inusemap) 873 free(pmp->pm_inusemap, M_MSDOSFSFAT); 874 free(pmp, M_MSDOSFSMNT); 875 mp->mnt_data = NULL; 876 } 877 return (error); 878 } 879 880 int 881 msdosfs_start(struct mount *mp, int flags) 882 { 883 884 return (0); 885 } 886 887 /* 888 * Unmount the filesystem described by mp. 889 */ 890 int 891 msdosfs_unmount(struct mount *mp, int mntflags) 892 { 893 struct msdosfsmount *pmp; 894 int error, flags; 895 896 flags = 0; 897 if (mntflags & MNT_FORCE) 898 flags |= FORCECLOSE; 899 if ((error = vflush(mp, NULLVP, flags)) != 0) 900 return (error); 901 pmp = VFSTOMSDOSFS(mp); 902 if (pmp->pm_devvp->v_type != VBAD) 903 spec_node_setmountedfs(pmp->pm_devvp, NULL); 904 #ifdef MSDOSFS_DEBUG 905 { 906 struct vnode *vp = pmp->pm_devvp; 907 908 printf("msdosfs_umount(): just before calling VOP_CLOSE()\n"); 909 printf("flag %08x, usecount %d, writecount %d, holdcnt %d\n", 910 vp->v_vflag | vp->v_iflag | vp->v_uflag, vp->v_usecount, 911 vp->v_writecount, vp->v_holdcnt); 912 printf("mount %p, op %p\n", 913 vp->v_mount, vp->v_op); 914 printf("freef %p, freeb %p, mount %p\n", 915 vp->v_freelist.tqe_next, vp->v_freelist.tqe_prev, 916 vp->v_mount); 917 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %d, type %d\n", 918 vp->v_cleanblkhd.lh_first, 919 vp->v_dirtyblkhd.lh_first, 920 vp->v_numoutput, vp->v_type); 921 printf("union %p, tag %d, data[0] %08x, data[1] %08x\n", 922 vp->v_socket, vp->v_tag, 923 ((u_int *)vp->v_data)[0], 924 ((u_int *)vp->v_data)[1]); 925 } 926 #endif 927 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 928 (void) VOP_CLOSE(pmp->pm_devvp, 929 pmp->pm_flags & MSDOSFSMNT_RONLY ? FREAD : FREAD|FWRITE, NOCRED); 930 vput(pmp->pm_devvp); 931 msdosfs_fh_destroy(pmp); 932 free(pmp->pm_inusemap, M_MSDOSFSFAT); 933 free(pmp, M_MSDOSFSMNT); 934 mp->mnt_data = NULL; 935 mp->mnt_flag &= ~MNT_LOCAL; 936 fstrans_unmount(mp); 937 return (0); 938 } 939 940 int 941 msdosfs_root(struct mount *mp, struct vnode **vpp) 942 { 943 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 944 int error; 945 946 #ifdef MSDOSFS_DEBUG 947 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 948 #endif 949 if ((error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, vpp)) != 0) 950 return error; 951 error = vn_lock(*vpp, LK_EXCLUSIVE); 952 if (error) { 953 vrele(*vpp); 954 *vpp = NULL; 955 return error; 956 } 957 return 0; 958 } 959 960 int 961 msdosfs_statvfs(struct mount *mp, struct statvfs *sbp) 962 { 963 struct msdosfsmount *pmp; 964 965 pmp = VFSTOMSDOSFS(mp); 966 sbp->f_bsize = pmp->pm_bpcluster; 967 sbp->f_frsize = sbp->f_bsize; 968 sbp->f_iosize = pmp->pm_bpcluster; 969 sbp->f_blocks = pmp->pm_nmbrofclusters; 970 sbp->f_bfree = pmp->pm_freeclustercount; 971 sbp->f_bavail = pmp->pm_freeclustercount; 972 sbp->f_bresvd = 0; 973 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 974 sbp->f_ffree = 0; /* what to put in here? */ 975 sbp->f_favail = 0; /* what to put in here? */ 976 sbp->f_fresvd = 0; 977 copy_statvfs_info(sbp, mp); 978 return (0); 979 } 980 981 struct msdosfs_sync_ctx { 982 int waitfor; 983 }; 984 985 static bool 986 msdosfs_sync_selector(void *cl, struct vnode *vp) 987 { 988 struct msdosfs_sync_ctx *c = cl; 989 struct denode *dep; 990 991 dep = VTODE(vp); 992 if (c->waitfor == MNT_LAZY || vp->v_type == VNON || 993 dep == NULL || (((dep->de_flag & 994 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0) && 995 (LIST_EMPTY(&vp->v_dirtyblkhd) && 996 UVM_OBJ_IS_CLEAN(&vp->v_uobj)))) 997 return false; 998 return true; 999 } 1000 1001 int 1002 msdosfs_sync(struct mount *mp, int waitfor, kauth_cred_t cred) 1003 { 1004 struct vnode *vp; 1005 struct vnode_iterator *marker; 1006 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 1007 int error, allerror = 0; 1008 struct msdosfs_sync_ctx ctx; 1009 1010 /* 1011 * If we ever switch to not updating all of the FATs all the time, 1012 * this would be the place to update them from the first one. 1013 */ 1014 if (pmp->pm_fmod != 0) { 1015 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 1016 panic("msdosfs_sync: rofs mod"); 1017 else { 1018 /* update FATs here */ 1019 } 1020 } 1021 fstrans_start(mp, FSTRANS_SHARED); 1022 /* 1023 * Write back each (modified) denode. 1024 */ 1025 vfs_vnode_iterator_init(mp, &marker); 1026 ctx.waitfor = waitfor; 1027 while ((vp = vfs_vnode_iterator_next(marker, msdosfs_sync_selector, 1028 &ctx))) 1029 { 1030 error = vn_lock(vp, LK_EXCLUSIVE); 1031 if (error) { 1032 vrele(vp); 1033 continue; 1034 } 1035 if ((error = VOP_FSYNC(vp, cred, 1036 waitfor == MNT_WAIT ? FSYNC_WAIT : 0, 0, 0)) != 0) 1037 allerror = error; 1038 vput(vp); 1039 } 1040 vfs_vnode_iterator_destroy(marker); 1041 1042 /* 1043 * Force stale file system control information to be flushed. 1044 */ 1045 if ((error = VOP_FSYNC(pmp->pm_devvp, cred, 1046 waitfor == MNT_WAIT ? FSYNC_WAIT : 0, 0, 0)) != 0) 1047 allerror = error; 1048 fstrans_done(mp); 1049 return (allerror); 1050 } 1051 1052 int 1053 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp) 1054 { 1055 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 1056 struct defid defh; 1057 uint32_t gen; 1058 int error; 1059 1060 if (fhp->fid_len != sizeof(struct defid)) { 1061 DPRINTF("fid_len %d %zd", fhp->fid_len, sizeof(struct defid)); 1062 return EINVAL; 1063 } 1064 memcpy(&defh, fhp, sizeof(defh)); 1065 error = msdosfs_fh_lookup(pmp, defh.defid_dirclust, defh.defid_dirofs, 1066 &gen); 1067 if (error == 0 && gen != defh.defid_gen) 1068 error = ESTALE; 1069 if (error) { 1070 *vpp = NULLVP; 1071 return error; 1072 } 1073 error = deget(pmp, defh.defid_dirclust, defh.defid_dirofs, vpp); 1074 if (error) { 1075 DPRINTF("deget %d", error); 1076 *vpp = NULLVP; 1077 return error; 1078 } 1079 error = vn_lock(*vpp, LK_EXCLUSIVE); 1080 if (error) { 1081 vrele(*vpp); 1082 *vpp = NULLVP; 1083 return error; 1084 } 1085 return 0; 1086 } 1087 1088 int 1089 msdosfs_vptofh(struct vnode *vp, struct fid *fhp, size_t *fh_size) 1090 { 1091 struct msdosfsmount *pmp = VFSTOMSDOSFS(vp->v_mount); 1092 struct denode *dep; 1093 struct defid defh; 1094 int error; 1095 1096 if (*fh_size < sizeof(struct defid)) { 1097 *fh_size = sizeof(struct defid); 1098 return E2BIG; 1099 } 1100 *fh_size = sizeof(struct defid); 1101 dep = VTODE(vp); 1102 memset(&defh, 0, sizeof(defh)); 1103 defh.defid_len = sizeof(struct defid); 1104 defh.defid_dirclust = dep->de_dirclust; 1105 defh.defid_dirofs = dep->de_diroffset; 1106 error = msdosfs_fh_enter(pmp, dep->de_dirclust, dep->de_diroffset, 1107 &defh.defid_gen); 1108 if (error == 0) 1109 memcpy(fhp, &defh, sizeof(defh)); 1110 return error; 1111 } 1112 1113 int 1114 msdosfs_vget(struct mount *mp, ino_t ino, 1115 struct vnode **vpp) 1116 { 1117 1118 return (EOPNOTSUPP); 1119 } 1120 1121 int 1122 msdosfs_suspendctl(struct mount *mp, int cmd) 1123 { 1124 int error; 1125 struct lwp *l = curlwp; 1126 1127 switch (cmd) { 1128 case SUSPEND_SUSPEND: 1129 if ((error = fstrans_setstate(mp, FSTRANS_SUSPENDING)) != 0) 1130 return error; 1131 error = msdosfs_sync(mp, MNT_WAIT, l->l_proc->p_cred); 1132 if (error == 0) 1133 error = fstrans_setstate(mp, FSTRANS_SUSPENDED); 1134 if (error != 0) { 1135 (void) fstrans_setstate(mp, FSTRANS_NORMAL); 1136 return error; 1137 } 1138 return 0; 1139 1140 case SUSPEND_RESUME: 1141 return fstrans_setstate(mp, FSTRANS_NORMAL); 1142 1143 default: 1144 return EINVAL; 1145 } 1146 } 1147
Indexes created Fri Oct 17 00:09:41 GMT 2025