1 /* $FreeBSD$ */ 2 /* $NetBSD: msdosfs_vfsops.c,v 1.51 1997/11/17 15:36:58 ws Exp $ */ 3 4 /*- 5 * SPDX-License-Identifier: BSD-4-Clause 6 * 7 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. 8 * Copyright (C) 1994, 1995, 1997 TooLs GmbH. 9 * All rights reserved. 10 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by TooLs GmbH. 23 * 4. The name of TooLs GmbH may not be used to endorse or promote products 24 * derived from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 29 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 31 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 32 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 33 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 34 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 35 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 */ 37 /*- 38 * Written by Paul Popelka (paulp@uts.amdahl.com) 39 * 40 * You can do anything you want with this software, just don't say you wrote 41 * it, and don't remove this notice. 42 * 43 * This software is provided "as is". 44 * 45 * The author supplies this software to be publicly redistributed on the 46 * understanding that the author is not responsible for the correct 47 * functioning of this software in any circumstances and is not liable for 48 * any damages caused by this software. 49 * 50 * October 1992 51 */ 52 53 #include <sys/param.h> 54 #include <sys/systm.h> 55 #include <sys/buf.h> 56 #include <sys/conf.h> 57 #include <sys/fcntl.h> 58 #include <sys/iconv.h> 59 #include <sys/kernel.h> 60 #include <sys/lock.h> 61 #include <sys/malloc.h> 62 #include <sys/mount.h> 63 #include <sys/mutex.h> 64 #include <sys/namei.h> 65 #include <sys/priv.h> 66 #include <sys/proc.h> 67 #include <sys/stat.h> 68 #include <sys/vnode.h> 69 70 #include <geom/geom.h> 71 #include <geom/geom_vfs.h> 72 73 #include <fs/msdosfs/bootsect.h> 74 #include <fs/msdosfs/bpb.h> 75 #include <fs/msdosfs/direntry.h> 76 #include <fs/msdosfs/denode.h> 77 #include <fs/msdosfs/fat.h> 78 #include <fs/msdosfs/msdosfsmount.h> 79 80 #ifdef MSDOSFS_DEBUG 81 #include <sys/rwlock.h> 82 #endif 83 84 static const char msdosfs_lock_msg[] = "fatlk"; 85 86 /* Mount options that we support. */ 87 static const char *msdosfs_opts[] = { 88 "async", "noatime", "noclusterr", "noclusterw", 89 "export", "force", "from", "sync", 90 "cs_dos", "cs_local", "cs_win", "dirmask", 91 "gid", "kiconv", "longname", 92 "longnames", "mask", "shortname", "shortnames", 93 "uid", "win95", "nowin95", 94 NULL 95 }; 96 97 #if 1 /*def PC98*/ 98 /* 99 * XXX - The boot signature formatted by NEC PC-98 DOS looks like a 100 * garbage or a random value :-{ 101 * If you want to use that broken-signatured media, define the 102 * following symbol even though PC/AT. 103 * (ex. mount PC-98 DOS formatted FD on PC/AT) 104 */ 105 #define MSDOSFS_NOCHECKSIG 106 #endif 107 108 MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); 109 static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); 110 111 struct iconv_functions *msdosfs_iconv; 112 113 static int update_mp(struct mount *mp, struct thread *td); 114 static int mountmsdosfs(struct vnode *devvp, struct mount *mp); 115 static vfs_fhtovp_t msdosfs_fhtovp; 116 static vfs_mount_t msdosfs_mount; 117 static vfs_root_t msdosfs_root; 118 static vfs_statfs_t msdosfs_statfs; 119 static vfs_sync_t msdosfs_sync; 120 static vfs_unmount_t msdosfs_unmount; 121 122 /* Maximum length of a character set name (arbitrary). */ 123 #define MAXCSLEN 64 124 125 static int 126 update_mp(struct mount *mp, struct thread *td) 127 { 128 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 129 void *dos, *win, *local; 130 int error, v; 131 132 if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { 133 if (msdosfs_iconv != NULL) { 134 error = vfs_getopt(mp->mnt_optnew, 135 "cs_win", &win, NULL); 136 if (!error) 137 error = vfs_getopt(mp->mnt_optnew, 138 "cs_local", &local, NULL); 139 if (!error) 140 error = vfs_getopt(mp->mnt_optnew, 141 "cs_dos", &dos, NULL); 142 if (!error) { 143 msdosfs_iconv->open(win, local, &pmp->pm_u2w); 144 msdosfs_iconv->open(local, win, &pmp->pm_w2u); 145 msdosfs_iconv->open(dos, local, &pmp->pm_u2d); 146 msdosfs_iconv->open(local, dos, &pmp->pm_d2u); 147 } 148 if (error != 0) 149 return (error); 150 } else { 151 pmp->pm_w2u = NULL; 152 pmp->pm_u2w = NULL; 153 pmp->pm_d2u = NULL; 154 pmp->pm_u2d = NULL; 155 } 156 } 157 158 if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1) 159 pmp->pm_gid = v; 160 if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1) 161 pmp->pm_uid = v; 162 if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1) 163 pmp->pm_mask = v & ALLPERMS; 164 if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1) 165 pmp->pm_dirmask = v & ALLPERMS; 166 vfs_flagopt(mp->mnt_optnew, "shortname", 167 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 168 vfs_flagopt(mp->mnt_optnew, "shortnames", 169 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 170 vfs_flagopt(mp->mnt_optnew, "longname", 171 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 172 vfs_flagopt(mp->mnt_optnew, "longnames", 173 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 174 vfs_flagopt(mp->mnt_optnew, "kiconv", 175 &pmp->pm_flags, MSDOSFSMNT_KICONV); 176 177 if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) 178 pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 179 else 180 pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; 181 182 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 183 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 184 else 185 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 186 return 0; 187 } 188 189 static int 190 msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags) 191 { 192 struct msdosfs_args args; 193 int error; 194 195 if (data == NULL) 196 return (EINVAL); 197 error = copyin(data, &args, sizeof args); 198 if (error) 199 return (error); 200 201 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 202 ma = mount_arg(ma, "export", &args.export, sizeof(args.export)); 203 ma = mount_argf(ma, "uid", "%d", args.uid); 204 ma = mount_argf(ma, "gid", "%d", args.gid); 205 ma = mount_argf(ma, "mask", "%d", args.mask); 206 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 207 208 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 209 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 210 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 211 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 212 213 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 214 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 215 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 216 217 error = kernel_mount(ma, flags); 218 219 return (error); 220 } 221 222 /* 223 * mp - path - addr in user space of mount point (ie /usr or whatever) 224 * data - addr in user space of mount params including the name of the block 225 * special file to treat as a filesystem. 226 */ 227 static int 228 msdosfs_mount(struct mount *mp) 229 { 230 struct vnode *devvp; /* vnode for blk device to mount */ 231 struct thread *td; 232 /* msdosfs specific mount control block */ 233 struct msdosfsmount *pmp = NULL; 234 struct nameidata ndp; 235 int error, flags; 236 accmode_t accmode; 237 char *from; 238 239 td = curthread; 240 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 241 return (EINVAL); 242 243 /* 244 * If updating, check whether changing from read-only to 245 * read/write; if there is no device name, that's all we do. 246 */ 247 if (mp->mnt_flag & MNT_UPDATE) { 248 pmp = VFSTOMSDOSFS(mp); 249 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 250 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 251 if ((error = vn_start_write(NULL, &mp, V_WAIT)) != 0) 252 return (error); 253 error = vfs_write_suspend_umnt(mp); 254 if (error != 0) 255 return (error); 256 257 flags = WRITECLOSE; 258 if (mp->mnt_flag & MNT_FORCE) 259 flags |= FORCECLOSE; 260 error = vflush(mp, 0, flags, td); 261 if (error != 0) { 262 vfs_write_resume(mp, 0); 263 return (error); 264 } 265 266 /* 267 * Now the volume is clean. Mark it so while the 268 * device is still rw. 269 */ 270 error = markvoldirty(pmp, 0); 271 if (error != 0) { 272 vfs_write_resume(mp, 0); 273 (void)markvoldirty(pmp, 1); 274 return (error); 275 } 276 277 /* Downgrade the device from rw to ro. */ 278 g_topology_lock(); 279 error = g_access(pmp->pm_cp, 0, -1, 0); 280 g_topology_unlock(); 281 if (error) { 282 vfs_write_resume(mp, 0); 283 (void)markvoldirty(pmp, 1); 284 return (error); 285 } 286 287 /* 288 * Backing out after an error was painful in the 289 * above. Now we are committed to succeeding. 290 */ 291 pmp->pm_fmod = 0; 292 pmp->pm_flags |= MSDOSFSMNT_RONLY; 293 MNT_ILOCK(mp); 294 mp->mnt_flag |= MNT_RDONLY; 295 MNT_IUNLOCK(mp); 296 vfs_write_resume(mp, 0); 297 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 298 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 299 /* 300 * If upgrade to read-write by non-root, then verify 301 * that user has necessary permissions on the device. 302 */ 303 devvp = pmp->pm_devvp; 304 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 305 error = VOP_ACCESS(devvp, VREAD | VWRITE, 306 td->td_ucred, td); 307 if (error) 308 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 309 if (error) { 310 VOP_UNLOCK(devvp); 311 return (error); 312 } 313 VOP_UNLOCK(devvp); 314 g_topology_lock(); 315 error = g_access(pmp->pm_cp, 0, 1, 0); 316 g_topology_unlock(); 317 if (error) 318 return (error); 319 320 /* Now that the volume is modifiable, mark it dirty. */ 321 error = markvoldirty_upgrade(pmp, true, true); 322 if (error) { 323 /* 324 * If dirtying the superblock failed, drop GEOM 325 * 'w' refs (we're still RO). 326 */ 327 g_topology_lock(); 328 (void)g_access(pmp->pm_cp, 0, -1, 0); 329 g_topology_unlock(); 330 331 return (error); 332 } 333 334 pmp->pm_fmod = 1; 335 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 336 MNT_ILOCK(mp); 337 mp->mnt_flag &= ~MNT_RDONLY; 338 MNT_IUNLOCK(mp); 339 } 340 } 341 /* 342 * Not an update, or updating the name: look up the name 343 * and verify that it refers to a sensible disk device. 344 */ 345 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 346 return (EINVAL); 347 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 348 error = namei(&ndp); 349 if (error) 350 return (error); 351 devvp = ndp.ni_vp; 352 NDFREE(&ndp, NDF_ONLY_PNBUF); 353 354 if (!vn_isdisk_error(devvp, &error)) { 355 vput(devvp); 356 return (error); 357 } 358 /* 359 * If mount by non-root, then verify that user has necessary 360 * permissions on the device. 361 */ 362 accmode = VREAD; 363 if ((mp->mnt_flag & MNT_RDONLY) == 0) 364 accmode |= VWRITE; 365 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 366 if (error) 367 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 368 if (error) { 369 vput(devvp); 370 return (error); 371 } 372 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 373 error = mountmsdosfs(devvp, mp); 374 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 375 pmp = VFSTOMSDOSFS(mp); 376 #endif 377 } else { 378 vput(devvp); 379 if (devvp != pmp->pm_devvp) 380 return (EINVAL); /* XXX needs translation */ 381 } 382 if (error) { 383 vrele(devvp); 384 return (error); 385 } 386 387 error = update_mp(mp, td); 388 if (error) { 389 if ((mp->mnt_flag & MNT_UPDATE) == 0) 390 msdosfs_unmount(mp, MNT_FORCE); 391 return error; 392 } 393 394 vfs_mountedfrom(mp, from); 395 #ifdef MSDOSFS_DEBUG 396 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 397 #endif 398 return (0); 399 } 400 401 static int 402 mountmsdosfs(struct vnode *devvp, struct mount *mp) 403 { 404 struct msdosfsmount *pmp; 405 struct buf *bp; 406 struct cdev *dev; 407 union bootsector *bsp; 408 struct byte_bpb33 *b33; 409 struct byte_bpb50 *b50; 410 struct byte_bpb710 *b710; 411 uint8_t SecPerClust; 412 u_long clusters; 413 int ronly, error; 414 struct g_consumer *cp; 415 struct bufobj *bo; 416 417 bp = NULL; /* This and pmp both used in error_exit. */ 418 pmp = NULL; 419 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 420 421 dev = devvp->v_rdev; 422 if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0, 423 (uintptr_t)mp) == 0) { 424 VOP_UNLOCK(devvp); 425 return (EBUSY); 426 } 427 g_topology_lock(); 428 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 429 g_topology_unlock(); 430 if (error != 0) { 431 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 432 VOP_UNLOCK(devvp); 433 return (error); 434 } 435 dev_ref(dev); 436 bo = &devvp->v_bufobj; 437 VOP_UNLOCK(devvp); 438 if (dev->si_iosize_max != 0) 439 mp->mnt_iosize_max = dev->si_iosize_max; 440 if (mp->mnt_iosize_max > maxphys) 441 mp->mnt_iosize_max = maxphys; 442 443 /* 444 * Read the boot sector of the filesystem, and then check the 445 * boot signature. If not a dos boot sector then error out. 446 * 447 * NOTE: 8192 is a magic size that works for ffs. 448 */ 449 error = bread(devvp, 0, 8192, NOCRED, &bp); 450 if (error) 451 goto error_exit; 452 bp->b_flags |= B_AGE; 453 bsp = (union bootsector *)bp->b_data; 454 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 455 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 456 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 457 458 #ifndef MSDOSFS_NOCHECKSIG 459 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 460 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 461 error = EINVAL; 462 goto error_exit; 463 } 464 #endif 465 466 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 467 pmp->pm_mountp = mp; 468 pmp->pm_cp = cp; 469 pmp->pm_bo = bo; 470 471 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); 472 lockinit(&pmp->pm_checkpath_lock, 0, "msdoscp", 0, 0); 473 474 /* 475 * Initialize ownerships and permissions, since nothing else will 476 * initialize them iff we are mounting root. 477 */ 478 pmp->pm_uid = UID_ROOT; 479 pmp->pm_gid = GID_WHEEL; 480 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 481 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 482 483 /* 484 * Compute several useful quantities from the bpb in the 485 * bootsector. Copy in the dos 5 variant of the bpb then fix up 486 * the fields that are different between dos 5 and dos 3.3. 487 */ 488 SecPerClust = b50->bpbSecPerClust; 489 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 490 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 491 error = EINVAL; 492 goto error_exit; 493 } 494 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 495 pmp->pm_FATs = b50->bpbFATs; 496 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 497 pmp->pm_Sectors = getushort(b50->bpbSectors); 498 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 499 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 500 pmp->pm_Heads = getushort(b50->bpbHeads); 501 pmp->pm_Media = b50->bpbMedia; 502 503 /* calculate the ratio of sector size to DEV_BSIZE */ 504 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 505 506 /* 507 * We don't check pm_Heads nor pm_SecPerTrack, because 508 * these may not be set for EFI file systems. We don't 509 * use these anyway, so we're unaffected if they are 510 * invalid. 511 */ 512 if (!pmp->pm_BytesPerSec || !SecPerClust) { 513 error = EINVAL; 514 goto error_exit; 515 } 516 517 if (pmp->pm_Sectors == 0) { 518 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 519 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 520 } else { 521 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 522 pmp->pm_HugeSectors = pmp->pm_Sectors; 523 } 524 525 if (pmp->pm_RootDirEnts == 0) { 526 if (pmp->pm_FATsecs 527 || getushort(b710->bpbFSVers)) { 528 error = EINVAL; 529 #ifdef MSDOSFS_DEBUG 530 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 531 #endif 532 goto error_exit; 533 } 534 pmp->pm_fatmask = FAT32_MASK; 535 pmp->pm_fatmult = 4; 536 pmp->pm_fatdiv = 1; 537 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 538 if (getushort(b710->bpbExtFlags) & FATMIRROR) 539 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 540 else 541 pmp->pm_flags |= MSDOSFS_FATMIRROR; 542 } else 543 pmp->pm_flags |= MSDOSFS_FATMIRROR; 544 545 /* 546 * Check a few values (could do some more): 547 * - logical sector size: power of 2, >= block size 548 * - sectors per cluster: power of 2, >= 1 549 * - number of sectors: >= 1, <= size of partition 550 * - number of FAT sectors: >= 1 551 */ 552 if ( (SecPerClust == 0) 553 || (SecPerClust & (SecPerClust - 1)) 554 || (pmp->pm_BytesPerSec < DEV_BSIZE) 555 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 556 || (pmp->pm_HugeSectors == 0) 557 || (pmp->pm_FATsecs == 0) 558 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) 559 ) { 560 error = EINVAL; 561 goto error_exit; 562 } 563 564 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 565 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 566 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 567 SecPerClust *= pmp->pm_BlkPerSec; 568 569 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 570 571 if (FAT32(pmp)) { 572 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 573 pmp->pm_firstcluster = pmp->pm_fatblk 574 + (pmp->pm_FATs * pmp->pm_FATsecs); 575 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 576 } else { 577 pmp->pm_rootdirblk = pmp->pm_fatblk + 578 (pmp->pm_FATs * pmp->pm_FATsecs); 579 pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts * 580 sizeof(struct direntry), DEV_BSIZE); /* in blocks */ 581 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 582 } 583 584 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 585 SecPerClust + 1; 586 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 587 588 if (pmp->pm_fatmask == 0) { 589 if (pmp->pm_maxcluster 590 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 591 /* 592 * This will usually be a floppy disk. This size makes 593 * sure that one FAT entry will not be split across 594 * multiple blocks. 595 */ 596 pmp->pm_fatmask = FAT12_MASK; 597 pmp->pm_fatmult = 3; 598 pmp->pm_fatdiv = 2; 599 } else { 600 pmp->pm_fatmask = FAT16_MASK; 601 pmp->pm_fatmult = 2; 602 pmp->pm_fatdiv = 1; 603 } 604 } 605 606 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 607 if (pmp->pm_maxcluster >= clusters) { 608 #ifdef MSDOSFS_DEBUG 609 printf("Warning: number of clusters (%ld) exceeds FAT " 610 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 611 #endif 612 pmp->pm_maxcluster = clusters - 1; 613 } 614 615 if (FAT12(pmp)) 616 pmp->pm_fatblocksize = 3 * 512; 617 else 618 pmp->pm_fatblocksize = PAGE_SIZE; 619 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 620 pmp->pm_BytesPerSec); 621 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 622 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 623 624 /* 625 * Compute mask and shift value for isolating cluster relative byte 626 * offsets and cluster numbers from a file offset. 627 */ 628 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 629 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 630 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 631 632 /* 633 * Check for valid cluster size 634 * must be a power of 2 635 */ 636 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 637 error = EINVAL; 638 goto error_exit; 639 } 640 641 /* 642 * Release the bootsector buffer. 643 */ 644 brelse(bp); 645 bp = NULL; 646 647 /* 648 * Check the fsinfo sector if we have one. Silently fix up our 649 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 650 * or too large. Ignore fp->fsinfree for now, since we need to 651 * read the entire FAT anyway to fill the inuse map. 652 */ 653 if (pmp->pm_fsinfo) { 654 struct fsinfo *fp; 655 656 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 657 NOCRED, &bp)) != 0) 658 goto error_exit; 659 fp = (struct fsinfo *)bp->b_data; 660 if (!bcmp(fp->fsisig1, "RRaA", 4) 661 && !bcmp(fp->fsisig2, "rrAa", 4) 662 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 663 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 664 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 665 pmp->pm_nxtfree = CLUST_FIRST; 666 } else 667 pmp->pm_fsinfo = 0; 668 brelse(bp); 669 bp = NULL; 670 } 671 672 /* 673 * Finish initializing pmp->pm_nxtfree (just in case the first few 674 * sectors aren't properly reserved in the FAT). This completes 675 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 676 * value if there is no fsinfo. We will use pmp->pm_nxtfree 677 * internally even if there is no fsinfo. 678 */ 679 if (pmp->pm_nxtfree < CLUST_FIRST) 680 pmp->pm_nxtfree = CLUST_FIRST; 681 682 /* 683 * Allocate memory for the bitmap of allocated clusters, and then 684 * fill it in. 685 */ 686 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 687 * sizeof(*pmp->pm_inusemap), 688 M_MSDOSFSFAT, M_WAITOK); 689 690 /* 691 * fillinusemap() needs pm_devvp. 692 */ 693 pmp->pm_devvp = devvp; 694 pmp->pm_dev = dev; 695 696 /* 697 * Have the inuse map filled in. 698 */ 699 MSDOSFS_LOCK_MP(pmp); 700 error = fillinusemap(pmp); 701 MSDOSFS_UNLOCK_MP(pmp); 702 if (error != 0) 703 goto error_exit; 704 705 /* 706 * If they want FAT updates to be synchronous then let them suffer 707 * the performance degradation in exchange for the on disk copy of 708 * the FAT being correct just about all the time. I suppose this 709 * would be a good thing to turn on if the kernel is still flakey. 710 */ 711 if (mp->mnt_flag & MNT_SYNCHRONOUS) 712 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 713 714 /* 715 * Finish up. 716 */ 717 if (ronly) 718 pmp->pm_flags |= MSDOSFSMNT_RONLY; 719 else { 720 if ((error = markvoldirty(pmp, 1)) != 0) 721 goto error_exit; 722 pmp->pm_fmod = 1; 723 } 724 mp->mnt_data = pmp; 725 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 726 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 727 MNT_ILOCK(mp); 728 mp->mnt_flag |= MNT_LOCAL; 729 mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF; 730 MNT_IUNLOCK(mp); 731 732 return (0); 733 734 error_exit: 735 if (bp) 736 brelse(bp); 737 if (cp != NULL) { 738 g_topology_lock(); 739 g_vfs_close(cp); 740 g_topology_unlock(); 741 } 742 if (pmp) { 743 lockdestroy(&pmp->pm_fatlock); 744 lockdestroy(&pmp->pm_checkpath_lock); 745 free(pmp->pm_inusemap, M_MSDOSFSFAT); 746 free(pmp, M_MSDOSFSMNT); 747 mp->mnt_data = NULL; 748 } 749 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 750 dev_rel(dev); 751 return (error); 752 } 753 754 /* 755 * Unmount the filesystem described by mp. 756 */ 757 static int 758 msdosfs_unmount(struct mount *mp, int mntflags) 759 { 760 struct msdosfsmount *pmp; 761 int error, flags; 762 bool susp; 763 764 error = flags = 0; 765 pmp = VFSTOMSDOSFS(mp); 766 susp = (pmp->pm_flags & MSDOSFSMNT_RONLY) == 0; 767 768 if (susp) { 769 error = vfs_write_suspend_umnt(mp); 770 if (error != 0) 771 return (error); 772 } 773 774 if ((mntflags & MNT_FORCE) != 0) 775 flags |= FORCECLOSE; 776 error = vflush(mp, 0, flags, curthread); 777 if (error != 0 && error != ENXIO) { 778 if (susp) 779 vfs_write_resume(mp, VR_START_WRITE); 780 return (error); 781 } 782 if (susp) { 783 error = markvoldirty(pmp, 0); 784 if (error != 0 && error != ENXIO) { 785 if (susp) 786 vfs_write_resume(mp, VR_START_WRITE); 787 (void)markvoldirty(pmp, 1); 788 return (error); 789 } 790 } 791 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 792 if (pmp->pm_w2u) 793 msdosfs_iconv->close(pmp->pm_w2u); 794 if (pmp->pm_u2w) 795 msdosfs_iconv->close(pmp->pm_u2w); 796 if (pmp->pm_d2u) 797 msdosfs_iconv->close(pmp->pm_d2u); 798 if (pmp->pm_u2d) 799 msdosfs_iconv->close(pmp->pm_u2d); 800 } 801 802 #ifdef MSDOSFS_DEBUG 803 { 804 struct vnode *vp = pmp->pm_devvp; 805 struct bufobj *bo; 806 807 bo = &vp->v_bufobj; 808 BO_LOCK(bo); 809 VI_LOCK(vp); 810 vn_printf(vp, 811 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 812 printf("freef %p, freeb %p, mount %p\n", 813 TAILQ_NEXT(vp, v_vnodelist), vp->v_vnodelist.tqe_prev, 814 vp->v_mount); 815 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %d, type %d\n", 816 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 817 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 818 vp->v_bufobj.bo_numoutput, vp->v_type); 819 VI_UNLOCK(vp); 820 BO_UNLOCK(bo); 821 } 822 #endif 823 if (susp) 824 vfs_write_resume(mp, VR_START_WRITE); 825 826 g_topology_lock(); 827 g_vfs_close(pmp->pm_cp); 828 g_topology_unlock(); 829 atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0); 830 vrele(pmp->pm_devvp); 831 dev_rel(pmp->pm_dev); 832 free(pmp->pm_inusemap, M_MSDOSFSFAT); 833 lockdestroy(&pmp->pm_fatlock); 834 lockdestroy(&pmp->pm_checkpath_lock); 835 free(pmp, M_MSDOSFSMNT); 836 mp->mnt_data = NULL; 837 MNT_ILOCK(mp); 838 mp->mnt_flag &= ~MNT_LOCAL; 839 MNT_IUNLOCK(mp); 840 return (error); 841 } 842 843 static int 844 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 845 { 846 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 847 struct denode *ndep; 848 int error; 849 850 #ifdef MSDOSFS_DEBUG 851 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 852 #endif 853 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, LK_EXCLUSIVE, &ndep); 854 if (error) 855 return (error); 856 *vpp = DETOV(ndep); 857 return (0); 858 } 859 860 static int 861 msdosfs_statfs(struct mount *mp, struct statfs *sbp) 862 { 863 struct msdosfsmount *pmp; 864 865 pmp = VFSTOMSDOSFS(mp); 866 sbp->f_bsize = pmp->pm_bpcluster; 867 sbp->f_iosize = pmp->pm_bpcluster; 868 sbp->f_blocks = pmp->pm_maxcluster + 1; 869 sbp->f_bfree = pmp->pm_freeclustercount; 870 sbp->f_bavail = pmp->pm_freeclustercount; 871 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 872 sbp->f_ffree = 0; /* what to put in here? */ 873 return (0); 874 } 875 876 /* 877 * If we have an FSInfo block, update it. 878 */ 879 static int 880 msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) 881 { 882 struct fsinfo *fp; 883 struct buf *bp; 884 int error; 885 886 MSDOSFS_LOCK_MP(pmp); 887 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { 888 error = 0; 889 goto unlock; 890 } 891 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 892 NOCRED, &bp); 893 if (error != 0) { 894 goto unlock; 895 } 896 fp = (struct fsinfo *)bp->b_data; 897 putulong(fp->fsinfree, pmp->pm_freeclustercount); 898 putulong(fp->fsinxtfree, pmp->pm_nxtfree); 899 pmp->pm_flags &= ~MSDOSFS_FSIMOD; 900 if (waitfor == MNT_WAIT) 901 error = bwrite(bp); 902 else 903 bawrite(bp); 904 unlock: 905 MSDOSFS_UNLOCK_MP(pmp); 906 return (error); 907 } 908 909 static int 910 msdosfs_sync(struct mount *mp, int waitfor) 911 { 912 struct vnode *vp, *nvp; 913 struct thread *td; 914 struct denode *dep; 915 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 916 int error, allerror = 0; 917 918 td = curthread; 919 920 /* 921 * If we ever switch to not updating all of the FATs all the time, 922 * this would be the place to update them from the first one. 923 */ 924 if (pmp->pm_fmod != 0) { 925 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 926 panic("msdosfs_sync: rofs mod"); 927 else { 928 /* update FATs here */ 929 } 930 } 931 /* 932 * Write back each (modified) denode. 933 */ 934 loop: 935 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { 936 if (vp->v_type == VNON) { 937 VI_UNLOCK(vp); 938 continue; 939 } 940 dep = VTODE(vp); 941 if ((dep->de_flag & 942 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 943 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 944 waitfor == MNT_LAZY)) { 945 VI_UNLOCK(vp); 946 continue; 947 } 948 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK); 949 if (error) { 950 if (error == ENOENT) { 951 MNT_VNODE_FOREACH_ALL_ABORT(mp, nvp); 952 goto loop; 953 } 954 continue; 955 } 956 error = VOP_FSYNC(vp, waitfor, td); 957 if (error) 958 allerror = error; 959 VOP_UNLOCK(vp); 960 vrele(vp); 961 } 962 963 /* 964 * Flush filesystem control info. 965 */ 966 if (waitfor != MNT_LAZY) { 967 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 968 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 969 if (error) 970 allerror = error; 971 VOP_UNLOCK(pmp->pm_devvp); 972 } 973 974 error = msdosfs_fsiflush(pmp, waitfor); 975 if (error != 0) 976 allerror = error; 977 978 if (allerror == 0 && waitfor == MNT_SUSPEND) { 979 MNT_ILOCK(mp); 980 mp->mnt_kern_flag |= MNTK_SUSPEND2 | MNTK_SUSPENDED; 981 MNT_IUNLOCK(mp); 982 } 983 return (allerror); 984 } 985 986 static int 987 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) 988 { 989 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 990 struct defid *defhp = (struct defid *) fhp; 991 struct denode *dep; 992 int error; 993 994 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, 995 LK_EXCLUSIVE, &dep); 996 if (error) { 997 *vpp = NULLVP; 998 return (error); 999 } 1000 *vpp = DETOV(dep); 1001 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 1002 return (0); 1003 } 1004 1005 static struct vfsops msdosfs_vfsops = { 1006 .vfs_fhtovp = msdosfs_fhtovp, 1007 .vfs_mount = msdosfs_mount, 1008 .vfs_cmount = msdosfs_cmount, 1009 .vfs_root = msdosfs_root, 1010 .vfs_statfs = msdosfs_statfs, 1011 .vfs_sync = msdosfs_sync, 1012 .vfs_unmount = msdosfs_unmount, 1013 }; 1014 1015 VFS_SET(msdosfs_vfsops, msdosfs, 0); 1016 MODULE_VERSION(msdosfs, 1); 1017