msdosfs_vfsops.c revision 1.131
1 /* $NetBSD: msdosfs_vfsops.c,v 1.131 2020/01/17 20:08:07 ad 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 1.131 2020/01/17 20:08:07 ad 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 error = msdosfs_root(mp, LK_EXCLUSIVE, &rtvp); 213 if (error != 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); 252 vfs_rele(mp); 253 return (error); 254 } 255 256 if ((error = update_mp(mp, &args)) != 0) { 257 (void)msdosfs_unmount(mp, 0); 258 vfs_unbusy(mp); 259 vfs_rele(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); 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; 285 286 if (args == NULL) 287 return EINVAL; 288 if (*data_len < sizeof *args) 289 return EINVAL; 290 291 if (mp->mnt_flag & MNT_GETARGS) { 292 pmp = VFSTOMSDOSFS(mp); 293 if (pmp == NULL) 294 return EIO; 295 args->fspec = NULL; 296 args->uid = pmp->pm_uid; 297 args->gid = pmp->pm_gid; 298 args->mask = pmp->pm_mask; 299 args->flags = pmp->pm_flags; 300 args->version = MSDOSFSMNT_VERSION; 301 args->dirmask = pmp->pm_dirmask; 302 args->gmtoff = pmp->pm_gmtoff; 303 *data_len = sizeof *args; 304 return 0; 305 } 306 307 /* 308 * If not versioned (i.e. using old mount_msdos(8)), fill in 309 * the additional structure items with suitable defaults. 310 */ 311 if ((args->flags & MSDOSFSMNT_VERSIONED) == 0) { 312 args->version = 1; 313 args->dirmask = args->mask; 314 } 315 316 /* 317 * Reset GMT offset for pre-v3 mount structure args. 318 */ 319 if (args->version < 3) 320 args->gmtoff = 0; 321 322 /* 323 * If updating, check whether changing from read-only to 324 * read/write; if there is no device name, that's all we do. 325 */ 326 if (mp->mnt_flag & MNT_UPDATE) { 327 pmp = VFSTOMSDOSFS(mp); 328 error = 0; 329 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 330 (mp->mnt_flag & MNT_RDONLY)) { 331 flags = WRITECLOSE; 332 if (mp->mnt_flag & MNT_FORCE) 333 flags |= FORCECLOSE; 334 error = vflush(mp, NULLVP, flags); 335 } 336 if (!error && (mp->mnt_flag & MNT_RELOAD)) 337 /* not yet implemented */ 338 error = EOPNOTSUPP; 339 if (error) { 340 DPRINTF("vflush %d", error); 341 return (error); 342 } 343 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 344 (mp->mnt_iflag & IMNT_WANTRDWR)) { 345 /* 346 * If upgrade to read-write by non-root, then verify 347 * that user has necessary permissions on the device. 348 * 349 * Permission to update a mount is checked higher, so 350 * here we presume updating the mount is okay (for 351 * example, as far as securelevel goes) which leaves us 352 * with the normal check. 353 */ 354 devvp = pmp->pm_devvp; 355 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 356 error = kauth_authorize_system(l->l_cred, 357 KAUTH_SYSTEM_MOUNT, KAUTH_REQ_SYSTEM_MOUNT_DEVICE, 358 mp, devvp, KAUTH_ARG(VREAD | VWRITE)); 359 VOP_UNLOCK(devvp); 360 DPRINTF("KAUTH_REQ_SYSTEM_MOUNT_DEVICE %d", error); 361 if (error) 362 return (error); 363 364 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 365 } 366 if (args->fspec == NULL) { 367 DPRINTF("missing fspec"); 368 return EINVAL; 369 } 370 } 371 /* 372 * Not an update, or updating the name: look up the name 373 * and verify that it refers to a sensible block device. 374 */ 375 error = namei_simple_user(args->fspec, 376 NSM_FOLLOW_NOEMULROOT, &devvp); 377 if (error != 0) { 378 DPRINTF("namei %d", error); 379 return (error); 380 } 381 382 if (devvp->v_type != VBLK) { 383 DPRINTF("not block"); 384 vrele(devvp); 385 return (ENOTBLK); 386 } 387 if (bdevsw_lookup(devvp->v_rdev) == NULL) { 388 DPRINTF("no block switch"); 389 vrele(devvp); 390 return (ENXIO); 391 } 392 /* 393 * If mount by non-root, then verify that user has necessary 394 * permissions on the device. 395 */ 396 accessmode = VREAD; 397 if ((mp->mnt_flag & MNT_RDONLY) == 0) 398 accessmode |= VWRITE; 399 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 400 error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_MOUNT, 401 KAUTH_REQ_SYSTEM_MOUNT_DEVICE, mp, devvp, KAUTH_ARG(accessmode)); 402 VOP_UNLOCK(devvp); 403 if (error) { 404 DPRINTF("KAUTH_REQ_SYSTEM_MOUNT_DEVICE %d", error); 405 vrele(devvp); 406 return (error); 407 } 408 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 409 int xflags; 410 411 if (mp->mnt_flag & MNT_RDONLY) 412 xflags = FREAD; 413 else 414 xflags = FREAD|FWRITE; 415 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 416 error = VOP_OPEN(devvp, xflags, FSCRED); 417 VOP_UNLOCK(devvp); 418 if (error) { 419 DPRINTF("VOP_OPEN %d", error); 420 goto fail; 421 } 422 error = msdosfs_mountfs(devvp, mp, l, args); 423 if (error) { 424 DPRINTF("msdosfs_mountfs %d", error); 425 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 426 (void) VOP_CLOSE(devvp, xflags, NOCRED); 427 VOP_UNLOCK(devvp); 428 goto fail; 429 } 430 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 431 pmp = VFSTOMSDOSFS(mp); 432 #endif 433 } else { 434 vrele(devvp); 435 if (devvp != pmp->pm_devvp) { 436 DPRINTF("devvp %p pmp %p", devvp, pmp->pm_devvp); 437 return (EINVAL); /* needs translation */ 438 } 439 } 440 if ((error = update_mp(mp, args)) != 0) { 441 msdosfs_unmount(mp, MNT_FORCE); 442 DPRINTF("update_mp %d", error); 443 return error; 444 } 445 446 #ifdef MSDOSFS_DEBUG 447 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 448 #endif 449 return set_statvfs_info(path, UIO_USERSPACE, args->fspec, UIO_USERSPACE, 450 mp->mnt_op->vfs_name, mp, l); 451 452 fail: 453 vrele(devvp); 454 return (error); 455 } 456 457 int 458 msdosfs_mountfs(struct vnode *devvp, struct mount *mp, struct lwp *l, struct msdosfs_args *argp) 459 { 460 struct msdosfsmount *pmp; 461 struct buf *bp; 462 dev_t dev = devvp->v_rdev; 463 union bootsector *bsp; 464 struct byte_bpb33 *b33; 465 struct byte_bpb50 *b50; 466 struct byte_bpb710 *b710; 467 uint8_t SecPerClust; 468 int ronly, error, BlkPerSec; 469 uint64_t psize; 470 unsigned secsize; 471 u_long fatbytes, fatblocksecs; 472 473 /* Flush out any old buffers remaining from a previous use. */ 474 if ((error = vinvalbuf(devvp, V_SAVE, l->l_cred, l, 0, 0)) != 0) 475 return (error); 476 477 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 478 479 bp = NULL; /* both used in error_exit */ 480 pmp = NULL; 481 482 error = getdisksize(devvp, &psize, &secsize); 483 if (error) { 484 if (argp->flags & MSDOSFSMNT_GEMDOSFS) 485 goto error_exit; 486 487 /* ok, so it failed. we most likely don't need the info */ 488 secsize = DEV_BSIZE; 489 psize = 0; 490 error = 0; 491 } 492 if (secsize < DEV_BSIZE) { 493 DPRINTF("Invalid block secsize (%d < DEV_BSIZE)", secsize); 494 error = EINVAL; 495 goto error_exit; 496 } 497 498 if (argp->flags & MSDOSFSMNT_GEMDOSFS) { 499 if (secsize != GEMDOSFS_BSIZE) { 500 DPRINTF("Invalid block secsize %d for GEMDOS", secsize); 501 error = EINVAL; 502 goto error_exit; 503 } 504 } 505 506 /* 507 * Read the boot sector of the filesystem, and then check the 508 * boot signature. If not a dos boot sector then error out. 509 */ 510 if (secsize < sizeof(*b50)) { 511 DPRINTF("50 bootsec %u\n", secsize); 512 error = EINVAL; 513 goto error_exit; 514 } 515 if ((error = bread(devvp, 0, secsize, 0, &bp)) != 0) 516 goto error_exit; 517 bsp = (union bootsector *)bp->b_data; 518 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 519 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 520 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 521 522 if (!(argp->flags & MSDOSFSMNT_GEMDOSFS)) { 523 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 524 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 525 DPRINTF("bootsig0 %d bootsig1 %d", 526 bsp->bs50.bsBootSectSig0, 527 bsp->bs50.bsBootSectSig1); 528 error = EINVAL; 529 goto error_exit; 530 } 531 } 532 533 pmp = malloc(sizeof(*pmp), M_MSDOSFSMNT, M_WAITOK|M_ZERO); 534 pmp->pm_mountp = mp; 535 536 /* 537 * Compute several useful quantities from the bpb in the 538 * bootsector. Copy in the dos 5 variant of the bpb then fix up 539 * the fields that are different between dos 5 and dos 3.3. 540 */ 541 SecPerClust = b50->bpbSecPerClust; 542 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 543 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 544 pmp->pm_FATs = b50->bpbFATs; 545 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 546 pmp->pm_Sectors = getushort(b50->bpbSectors); 547 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 548 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 549 pmp->pm_Heads = getushort(b50->bpbHeads); 550 pmp->pm_Media = b50->bpbMedia; 551 552 if (pmp->pm_Sectors == 0) { 553 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 554 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 555 } else { 556 if (secsize < sizeof(*b33)) { 557 DPRINTF("33 bootsec %u\n", secsize); 558 error = EINVAL; 559 goto error_exit; 560 } 561 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 562 pmp->pm_HugeSectors = pmp->pm_Sectors; 563 } 564 565 /* 566 * Sanity checks, from the FAT specification: 567 * - sectors per cluster: >= 1, power of 2 568 * - logical sector size: >= 1, power of 2 569 * - cluster size: <= max FS block size 570 * - number of sectors: >= 1 571 */ 572 if ((SecPerClust == 0) || !powerof2(SecPerClust) || 573 (pmp->pm_BytesPerSec == 0) || !powerof2(pmp->pm_BytesPerSec) || 574 (SecPerClust * pmp->pm_BytesPerSec > MAXBSIZE) || 575 (pmp->pm_HugeSectors == 0)) { 576 DPRINTF("consistency checks"); 577 error = EINVAL; 578 goto error_exit; 579 } 580 581 if (!(argp->flags & MSDOSFSMNT_GEMDOSFS) && 582 (pmp->pm_SecPerTrack > 63)) { 583 DPRINTF("SecPerTrack %d", pmp->pm_SecPerTrack); 584 error = EINVAL; 585 goto error_exit; 586 } 587 588 if (pmp->pm_RootDirEnts == 0) { 589 if (secsize < sizeof(*b710)) { 590 DPRINTF("710 bootsec %u\n", secsize); 591 error = EINVAL; 592 goto error_exit; 593 } 594 unsigned short FSVers = getushort(b710->bpbFSVers); 595 unsigned short ExtFlags = getushort(b710->bpbExtFlags); 596 /* 597 * Some say that bsBootSectSig[23] must be zero, but 598 * Windows does not require this and some digital cameras 599 * do not set these to zero. Therefore, do not insist. 600 */ 601 if (pmp->pm_Sectors || pmp->pm_FATsecs || FSVers) { 602 DPRINTF("Sectors %d FATsecs %lu FSVers %d", 603 pmp->pm_Sectors, pmp->pm_FATsecs, FSVers); 604 error = EINVAL; 605 goto error_exit; 606 } 607 pmp->pm_fatmask = FAT32_MASK; 608 pmp->pm_fatmult = 4; 609 pmp->pm_fatdiv = 1; 610 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 611 612 /* Mirroring is enabled if the FATMIRROR bit is not set. */ 613 if ((ExtFlags & FATMIRROR) == 0) 614 pmp->pm_flags |= MSDOSFS_FATMIRROR; 615 else 616 pmp->pm_curfat = ExtFlags & FATNUM; 617 } else 618 pmp->pm_flags |= MSDOSFS_FATMIRROR; 619 620 if (argp->flags & MSDOSFSMNT_GEMDOSFS) { 621 if (FAT32(pmp)) { 622 /* GEMDOS doesn't know FAT32. */ 623 DPRINTF("FAT32 for GEMDOS"); 624 error = EINVAL; 625 goto error_exit; 626 } 627 628 /* 629 * Check a few values (could do some more): 630 * - logical sector size: >= block size 631 * - number of sectors: <= size of partition 632 */ 633 if ((pmp->pm_BytesPerSec < GEMDOSFS_BSIZE) || 634 (pmp->pm_HugeSectors * 635 (pmp->pm_BytesPerSec / GEMDOSFS_BSIZE) > psize)) { 636 DPRINTF("consistency checks for GEMDOS"); 637 error = EINVAL; 638 goto error_exit; 639 } 640 /* 641 * XXX - Many parts of the msdosfs driver seem to assume that 642 * the number of bytes per logical sector (BytesPerSec) will 643 * always be the same as the number of bytes per disk block 644 * Let's pretend it is. 645 */ 646 BlkPerSec = pmp->pm_BytesPerSec / GEMDOSFS_BSIZE; 647 pmp->pm_BytesPerSec = GEMDOSFS_BSIZE; 648 pmp->pm_HugeSectors *= BlkPerSec; 649 pmp->pm_HiddenSects *= BlkPerSec; 650 pmp->pm_ResSectors *= BlkPerSec; 651 pmp->pm_Sectors *= BlkPerSec; 652 pmp->pm_FATsecs *= BlkPerSec; 653 SecPerClust *= BlkPerSec; 654 } 655 656 /* Check that fs has nonzero FAT size */ 657 if (pmp->pm_FATsecs == 0) { 658 DPRINTF("FATsecs is 0"); 659 error = EINVAL; 660 goto error_exit; 661 } 662 663 pmp->pm_fatblk = pmp->pm_ResSectors; 664 if (FAT32(pmp)) { 665 if (secsize < sizeof(*b710)) { 666 DPRINTF("710 bootsec %u\n", secsize); 667 error = EINVAL; 668 goto error_exit; 669 } 670 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 671 pmp->pm_firstcluster = pmp->pm_fatblk 672 + (pmp->pm_FATs * pmp->pm_FATsecs); 673 pmp->pm_fsinfo = getushort(b710->bpbFSInfo); 674 } else { 675 pmp->pm_rootdirblk = pmp->pm_fatblk + 676 (pmp->pm_FATs * pmp->pm_FATsecs); 677 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 678 + pmp->pm_BytesPerSec - 1) 679 / pmp->pm_BytesPerSec;/* in sectors */ 680 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 681 } 682 683 pmp->pm_nmbrofclusters = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 684 SecPerClust; 685 pmp->pm_maxcluster = pmp->pm_nmbrofclusters + 1; 686 pmp->pm_fatsize = pmp->pm_FATsecs * pmp->pm_BytesPerSec; 687 688 if (argp->flags & MSDOSFSMNT_GEMDOSFS) { 689 if (pmp->pm_nmbrofclusters <= (0xff0 - 2)) { 690 pmp->pm_fatmask = FAT12_MASK; 691 pmp->pm_fatmult = 3; 692 pmp->pm_fatdiv = 2; 693 } else { 694 pmp->pm_fatmask = FAT16_MASK; 695 pmp->pm_fatmult = 2; 696 pmp->pm_fatdiv = 1; 697 } 698 } else if (pmp->pm_fatmask == 0) { 699 if (pmp->pm_maxcluster 700 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 701 /* 702 * This will usually be a floppy disk. This size makes 703 * sure that one FAT entry will not be split across 704 * multiple blocks. 705 */ 706 pmp->pm_fatmask = FAT12_MASK; 707 pmp->pm_fatmult = 3; 708 pmp->pm_fatdiv = 2; 709 } else { 710 pmp->pm_fatmask = FAT16_MASK; 711 pmp->pm_fatmult = 2; 712 pmp->pm_fatdiv = 1; 713 } 714 } 715 716 /* validate cluster count against FAT */ 717 if ((pmp->pm_maxcluster & pmp->pm_fatmask) != pmp->pm_maxcluster) { 718 DPRINTF("maxcluster %lu outside of mask %#lx\n", 719 pmp->pm_maxcluster, pmp->pm_fatmask); 720 error = EINVAL; 721 goto error_exit; 722 } 723 724 /* validate FAT size */ 725 fatbytes = (pmp->pm_maxcluster+1) * pmp->pm_fatmult / pmp->pm_fatdiv; 726 fatblocksecs = howmany(fatbytes, pmp->pm_BytesPerSec); 727 728 if (pmp->pm_FATsecs < fatblocksecs) { 729 DPRINTF("FATsecs %lu < real %lu\n", pmp->pm_FATsecs, 730 fatblocksecs); 731 error = EINVAL; 732 goto error_exit; 733 } 734 735 if (FAT12(pmp)) { 736 /* 737 * limit block size to what is needed to read a FAT block 738 * to not exceed MAXBSIZE 739 */ 740 pmp->pm_fatblocksec = uimin(3, fatblocksecs); 741 pmp->pm_fatblocksize = pmp->pm_fatblocksec 742 * pmp->pm_BytesPerSec; 743 } else { 744 pmp->pm_fatblocksize = MAXBSIZE; 745 pmp->pm_fatblocksec = pmp->pm_fatblocksize 746 / pmp->pm_BytesPerSec; 747 } 748 749 pmp->pm_bnshift = ffs(pmp->pm_BytesPerSec) - 1; 750 751 /* 752 * Compute mask and shift value for isolating cluster relative byte 753 * offsets and cluster numbers from a file offset. 754 */ 755 pmp->pm_bpcluster = SecPerClust * pmp->pm_BytesPerSec; 756 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 757 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 758 759 /* 760 * Check for valid cluster size 761 * must be a power of 2 762 */ 763 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 764 DPRINTF("bpcluster %lu cnshift %lu", pmp->pm_bpcluster, 765 pmp->pm_cnshift); 766 error = EINVAL; 767 goto error_exit; 768 } 769 770 /* 771 * Cluster size must be within limit of MAXBSIZE. 772 * Many FAT filesystems will not have clusters larger than 773 * 32KiB due to limits in Windows versions before Vista. 774 */ 775 if (pmp->pm_bpcluster > MAXBSIZE) { 776 DPRINTF("bpcluster %lu > MAXBSIZE %d", 777 pmp->pm_bpcluster, MAXBSIZE); 778 error = EINVAL; 779 goto error_exit; 780 } 781 782 /* 783 * Release the bootsector buffer. 784 */ 785 brelse(bp, BC_AGE); 786 bp = NULL; 787 788 /* 789 * Check FSInfo. 790 */ 791 if (pmp->pm_fsinfo) { 792 struct fsinfo *fp; 793 const int rdsz = roundup(sizeof(*fp), pmp->pm_BytesPerSec); 794 795 /* 796 * XXX If the fsinfo block is stored on media with 797 * 2KB or larger sectors, is the fsinfo structure 798 * padded at the end or in the middle? 799 */ 800 if ((error = bread(devvp, de_bn2kb(pmp, pmp->pm_fsinfo), 801 rdsz, 0, &bp)) != 0) 802 goto error_exit; 803 fp = (struct fsinfo *)bp->b_data; 804 if (!memcmp(fp->fsisig1, "RRaA", 4) 805 && !memcmp(fp->fsisig2, "rrAa", 4) 806 && !memcmp(fp->fsisig3, "\0\0\125\252", 4) 807 && !memcmp(fp->fsisig4, "\0\0\125\252", 4)) 808 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 809 else 810 pmp->pm_fsinfo = 0; 811 brelse(bp, 0); 812 bp = NULL; 813 } 814 815 /* 816 * Check and validate (or perhaps invalidate?) the fsinfo structure? 817 * XXX 818 */ 819 if (pmp->pm_fsinfo) { 820 if ((pmp->pm_nxtfree == 0xffffffffUL) || 821 (pmp->pm_nxtfree > pmp->pm_maxcluster)) 822 pmp->pm_fsinfo = 0; 823 } 824 825 /* 826 * Allocate memory for the bitmap of allocated clusters, and then 827 * fill it in. 828 */ 829 pmp->pm_inusemap = malloc(((pmp->pm_maxcluster + N_INUSEBITS) 830 / N_INUSEBITS) 831 * sizeof(*pmp->pm_inusemap), 832 M_MSDOSFSFAT, M_WAITOK); 833 834 /* 835 * fillinusemap() needs pm_devvp. 836 */ 837 pmp->pm_dev = dev; 838 pmp->pm_devvp = devvp; 839 840 /* 841 * Have the inuse map filled in. 842 */ 843 if ((error = fillinusemap(pmp)) != 0) { 844 DPRINTF("fillinusemap %d", error); 845 goto error_exit; 846 } 847 848 /* 849 * If they want FAT updates to be synchronous then let them suffer 850 * the performance degradation in exchange for the on disk copy of 851 * the FAT being correct just about all the time. I suppose this 852 * would be a good thing to turn on if the kernel is still flakey. 853 */ 854 if (mp->mnt_flag & MNT_SYNCHRONOUS) 855 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 856 857 /* 858 * Finish up. 859 */ 860 if (ronly) 861 pmp->pm_flags |= MSDOSFSMNT_RONLY; 862 else 863 pmp->pm_fmod = 1; 864 mp->mnt_data = pmp; 865 mp->mnt_stat.f_fsidx.__fsid_val[0] = (long)dev; 866 mp->mnt_stat.f_fsidx.__fsid_val[1] = makefstype(MOUNT_MSDOS); 867 mp->mnt_stat.f_fsid = mp->mnt_stat.f_fsidx.__fsid_val[0]; 868 mp->mnt_stat.f_namemax = MSDOSFS_NAMEMAX(pmp); 869 mp->mnt_flag |= MNT_LOCAL; 870 mp->mnt_dev_bshift = pmp->pm_bnshift; 871 mp->mnt_fs_bshift = pmp->pm_cnshift; 872 873 /* 874 * If we ever do quotas for DOS filesystems this would be a place 875 * to fill in the info in the msdosfsmount structure. You dolt, 876 * quotas on dos filesystems make no sense because files have no 877 * owners on dos filesystems. of course there is some empty space 878 * in the directory entry where we could put uid's and gid's. 879 */ 880 881 spec_node_setmountedfs(devvp, mp); 882 883 return (0); 884 885 error_exit: 886 if (bp) 887 brelse(bp, BC_AGE); 888 if (pmp) { 889 if (pmp->pm_inusemap) 890 free(pmp->pm_inusemap, M_MSDOSFSFAT); 891 free(pmp, M_MSDOSFSMNT); 892 mp->mnt_data = NULL; 893 } 894 return (error); 895 } 896 897 int 898 msdosfs_start(struct mount *mp, int flags) 899 { 900 901 return (0); 902 } 903 904 /* 905 * Unmount the filesystem described by mp. 906 */ 907 int 908 msdosfs_unmount(struct mount *mp, int mntflags) 909 { 910 struct msdosfsmount *pmp; 911 int error, flags; 912 913 flags = 0; 914 if (mntflags & MNT_FORCE) 915 flags |= FORCECLOSE; 916 if ((error = vflush(mp, NULLVP, flags)) != 0) 917 return (error); 918 pmp = VFSTOMSDOSFS(mp); 919 if (pmp->pm_devvp->v_type != VBAD) 920 spec_node_setmountedfs(pmp->pm_devvp, NULL); 921 #ifdef MSDOSFS_DEBUG 922 { 923 struct vnode *vp = pmp->pm_devvp; 924 925 printf("msdosfs_umount(): just before calling VOP_CLOSE()\n"); 926 printf("flag %08x, usecount %d, writecount %d, holdcnt %d\n", 927 vp->v_vflag | vp->v_iflag | vp->v_uflag, vp->v_usecount, 928 vp->v_writecount, vp->v_holdcnt); 929 printf("mount %p, op %p\n", 930 vp->v_mount, vp->v_op); 931 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %d, type %d\n", 932 vp->v_cleanblkhd.lh_first, 933 vp->v_dirtyblkhd.lh_first, 934 vp->v_numoutput, vp->v_type); 935 printf("union %p, tag %d, data[0] %08x, data[1] %08x\n", 936 vp->v_socket, vp->v_tag, 937 ((u_int *)vp->v_data)[0], 938 ((u_int *)vp->v_data)[1]); 939 } 940 #endif 941 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 942 (void) VOP_CLOSE(pmp->pm_devvp, 943 pmp->pm_flags & MSDOSFSMNT_RONLY ? FREAD : FREAD|FWRITE, NOCRED); 944 vput(pmp->pm_devvp); 945 msdosfs_fh_destroy(pmp); 946 free(pmp->pm_inusemap, M_MSDOSFSFAT); 947 free(pmp, M_MSDOSFSMNT); 948 mp->mnt_data = NULL; 949 mp->mnt_flag &= ~MNT_LOCAL; 950 return (0); 951 } 952 953 int 954 msdosfs_root(struct mount *mp, int lktype, struct vnode **vpp) 955 { 956 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 957 int error; 958 959 #ifdef MSDOSFS_DEBUG 960 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 961 #endif 962 if ((error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, vpp)) != 0) 963 return error; 964 error = vn_lock(*vpp, lktype); 965 if (error) { 966 vrele(*vpp); 967 *vpp = NULL; 968 return error; 969 } 970 return 0; 971 } 972 973 int 974 msdosfs_statvfs(struct mount *mp, struct statvfs *sbp) 975 { 976 struct msdosfsmount *pmp; 977 978 pmp = VFSTOMSDOSFS(mp); 979 sbp->f_bsize = pmp->pm_bpcluster; 980 sbp->f_frsize = sbp->f_bsize; 981 sbp->f_iosize = pmp->pm_bpcluster; 982 sbp->f_blocks = pmp->pm_nmbrofclusters; 983 sbp->f_bfree = pmp->pm_freeclustercount; 984 sbp->f_bavail = pmp->pm_freeclustercount; 985 sbp->f_bresvd = 0; 986 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 987 sbp->f_ffree = 0; /* what to put in here? */ 988 sbp->f_favail = 0; /* what to put in here? */ 989 sbp->f_fresvd = 0; 990 copy_statvfs_info(sbp, mp); 991 return (0); 992 } 993 994 struct msdosfs_sync_ctx { 995 int waitfor; 996 }; 997 998 static bool 999 msdosfs_sync_selector(void *cl, struct vnode *vp) 1000 { 1001 struct msdosfs_sync_ctx *c = cl; 1002 struct denode *dep; 1003 1004 KASSERT(mutex_owned(vp->v_interlock)); 1005 1006 dep = VTODE(vp); 1007 if (c->waitfor == MNT_LAZY || vp->v_type == VNON || 1008 dep == NULL || (((dep->de_flag & 1009 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0) && 1010 (LIST_EMPTY(&vp->v_dirtyblkhd) && 1011 UVM_OBJ_IS_CLEAN(&vp->v_uobj)))) 1012 return false; 1013 return true; 1014 } 1015 1016 int 1017 msdosfs_sync(struct mount *mp, int waitfor, kauth_cred_t cred) 1018 { 1019 struct vnode *vp; 1020 struct vnode_iterator *marker; 1021 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 1022 int error, allerror = 0; 1023 struct msdosfs_sync_ctx ctx; 1024 1025 /* 1026 * If we ever switch to not updating all of the FATs all the time, 1027 * this would be the place to update them from the first one. 1028 */ 1029 if (pmp->pm_fmod != 0) { 1030 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 1031 panic("msdosfs_sync: rofs mod"); 1032 else { 1033 /* update FATs here */ 1034 } 1035 } 1036 /* 1037 * Write back each (modified) denode. 1038 */ 1039 vfs_vnode_iterator_init(mp, &marker); 1040 ctx.waitfor = waitfor; 1041 while ((vp = vfs_vnode_iterator_next(marker, msdosfs_sync_selector, 1042 &ctx))) 1043 { 1044 error = vn_lock(vp, LK_EXCLUSIVE); 1045 if (error) { 1046 vrele(vp); 1047 continue; 1048 } 1049 if ((error = VOP_FSYNC(vp, cred, 1050 waitfor == MNT_WAIT ? FSYNC_WAIT : 0, 0, 0)) != 0) 1051 allerror = error; 1052 vput(vp); 1053 } 1054 vfs_vnode_iterator_destroy(marker); 1055 1056 /* 1057 * Force stale file system control information to be flushed. 1058 */ 1059 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 1060 if ((error = VOP_FSYNC(pmp->pm_devvp, cred, 1061 waitfor == MNT_WAIT ? FSYNC_WAIT : 0, 0, 0)) != 0) 1062 allerror = error; 1063 VOP_UNLOCK(pmp->pm_devvp); 1064 return (allerror); 1065 } 1066 1067 int 1068 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int lktype, struct vnode **vpp) 1069 { 1070 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 1071 struct defid defh; 1072 uint32_t gen; 1073 int error; 1074 1075 if (fhp->fid_len != sizeof(struct defid)) { 1076 DPRINTF("fid_len %d %zd", fhp->fid_len, sizeof(struct defid)); 1077 return EINVAL; 1078 } 1079 memcpy(&defh, fhp, sizeof(defh)); 1080 error = msdosfs_fh_lookup(pmp, defh.defid_dirclust, defh.defid_dirofs, 1081 &gen); 1082 if (error == 0 && gen != defh.defid_gen) 1083 error = ESTALE; 1084 if (error) { 1085 *vpp = NULLVP; 1086 return error; 1087 } 1088 error = deget(pmp, defh.defid_dirclust, defh.defid_dirofs, vpp); 1089 if (error) { 1090 DPRINTF("deget %d", error); 1091 *vpp = NULLVP; 1092 return error; 1093 } 1094 error = vn_lock(*vpp, lktype); 1095 if (error) { 1096 vrele(*vpp); 1097 *vpp = NULLVP; 1098 return error; 1099 } 1100 return 0; 1101 } 1102 1103 int 1104 msdosfs_vptofh(struct vnode *vp, struct fid *fhp, size_t *fh_size) 1105 { 1106 struct msdosfsmount *pmp = VFSTOMSDOSFS(vp->v_mount); 1107 struct denode *dep; 1108 struct defid defh; 1109 int error; 1110 1111 if (*fh_size < sizeof(struct defid)) { 1112 *fh_size = sizeof(struct defid); 1113 return E2BIG; 1114 } 1115 *fh_size = sizeof(struct defid); 1116 dep = VTODE(vp); 1117 memset(&defh, 0, sizeof(defh)); 1118 defh.defid_len = sizeof(struct defid); 1119 defh.defid_dirclust = dep->de_dirclust; 1120 defh.defid_dirofs = dep->de_diroffset; 1121 error = msdosfs_fh_enter(pmp, dep->de_dirclust, dep->de_diroffset, 1122 &defh.defid_gen); 1123 if (error == 0) 1124 memcpy(fhp, &defh, sizeof(defh)); 1125 return error; 1126 } 1127 1128 int 1129 msdosfs_vget(struct mount *mp, ino_t ino, int lktype, 1130 struct vnode **vpp) 1131 { 1132 1133 return (EOPNOTSUPP); 1134 } 1135
Indexes created Fri Sep 26 08:10:20 GMT 2025