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 error = VFS_SYNC(mp, MNT_WAIT); 252 if (error) 253 return (error); 254 flags = WRITECLOSE; 255 if (mp->mnt_flag & MNT_FORCE) 256 flags |= FORCECLOSE; 257 error = vflush(mp, 0, flags, td); 258 if (error) 259 return (error); 260 261 /* 262 * Now the volume is clean. Mark it so while the 263 * device is still rw. 264 */ 265 error = markvoldirty(pmp, 0); 266 if (error) { 267 (void)markvoldirty(pmp, 1); 268 return (error); 269 } 270 271 /* Downgrade the device from rw to ro. */ 272 g_topology_lock(); 273 error = g_access(pmp->pm_cp, 0, -1, 0); 274 g_topology_unlock(); 275 if (error) { 276 (void)markvoldirty(pmp, 1); 277 return (error); 278 } 279 280 /* 281 * Backing out after an error was painful in the 282 * above. Now we are committed to succeeding. 283 */ 284 pmp->pm_fmod = 0; 285 pmp->pm_flags |= MSDOSFSMNT_RONLY; 286 MNT_ILOCK(mp); 287 mp->mnt_flag |= MNT_RDONLY; 288 MNT_IUNLOCK(mp); 289 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 290 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 291 /* 292 * If upgrade to read-write by non-root, then verify 293 * that user has necessary permissions on the device. 294 */ 295 devvp = pmp->pm_devvp; 296 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 297 error = VOP_ACCESS(devvp, VREAD | VWRITE, 298 td->td_ucred, td); 299 if (error) 300 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 301 if (error) { 302 VOP_UNLOCK(devvp); 303 return (error); 304 } 305 VOP_UNLOCK(devvp); 306 g_topology_lock(); 307 error = g_access(pmp->pm_cp, 0, 1, 0); 308 g_topology_unlock(); 309 if (error) 310 return (error); 311 312 /* Now that the volume is modifiable, mark it dirty. */ 313 error = markvoldirty_upgrade(pmp, true, true); 314 if (error) { 315 /* 316 * If dirtying the superblock failed, drop GEOM 317 * 'w' refs (we're still RO). 318 */ 319 g_topology_lock(); 320 (void)g_access(pmp->pm_cp, 0, -1, 0); 321 g_topology_unlock(); 322 323 return (error); 324 } 325 326 pmp->pm_fmod = 1; 327 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 328 MNT_ILOCK(mp); 329 mp->mnt_flag &= ~MNT_RDONLY; 330 MNT_IUNLOCK(mp); 331 } 332 } 333 /* 334 * Not an update, or updating the name: look up the name 335 * and verify that it refers to a sensible disk device. 336 */ 337 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 338 return (EINVAL); 339 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 340 error = namei(&ndp); 341 if (error) 342 return (error); 343 devvp = ndp.ni_vp; 344 NDFREE(&ndp, NDF_ONLY_PNBUF); 345 346 if (!vn_isdisk(devvp, &error)) { 347 vput(devvp); 348 return (error); 349 } 350 /* 351 * If mount by non-root, then verify that user has necessary 352 * permissions on the device. 353 */ 354 accmode = VREAD; 355 if ((mp->mnt_flag & MNT_RDONLY) == 0) 356 accmode |= VWRITE; 357 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 358 if (error) 359 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 360 if (error) { 361 vput(devvp); 362 return (error); 363 } 364 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 365 error = mountmsdosfs(devvp, mp); 366 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 367 pmp = VFSTOMSDOSFS(mp); 368 #endif 369 } else { 370 vput(devvp); 371 if (devvp != pmp->pm_devvp) 372 return (EINVAL); /* XXX needs translation */ 373 } 374 if (error) { 375 vrele(devvp); 376 return (error); 377 } 378 379 error = update_mp(mp, td); 380 if (error) { 381 if ((mp->mnt_flag & MNT_UPDATE) == 0) 382 msdosfs_unmount(mp, MNT_FORCE); 383 return error; 384 } 385 386 vfs_mountedfrom(mp, from); 387 #ifdef MSDOSFS_DEBUG 388 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 389 #endif 390 return (0); 391 } 392 393 static int 394 mountmsdosfs(struct vnode *devvp, struct mount *mp) 395 { 396 struct msdosfsmount *pmp; 397 struct buf *bp; 398 struct cdev *dev; 399 union bootsector *bsp; 400 struct byte_bpb33 *b33; 401 struct byte_bpb50 *b50; 402 struct byte_bpb710 *b710; 403 uint8_t SecPerClust; 404 u_long clusters; 405 int ronly, error; 406 struct g_consumer *cp; 407 struct bufobj *bo; 408 409 bp = NULL; /* This and pmp both used in error_exit. */ 410 pmp = NULL; 411 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 412 413 dev = devvp->v_rdev; 414 if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0, 415 (uintptr_t)mp) == 0) { 416 VOP_UNLOCK(devvp); 417 return (EBUSY); 418 } 419 g_topology_lock(); 420 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 421 g_topology_unlock(); 422 if (error != 0) { 423 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 424 VOP_UNLOCK(devvp); 425 return (error); 426 } 427 dev_ref(dev); 428 bo = &devvp->v_bufobj; 429 VOP_UNLOCK(devvp); 430 if (dev->si_iosize_max != 0) 431 mp->mnt_iosize_max = dev->si_iosize_max; 432 if (mp->mnt_iosize_max > MAXPHYS) 433 mp->mnt_iosize_max = MAXPHYS; 434 435 /* 436 * Read the boot sector of the filesystem, and then check the 437 * boot signature. If not a dos boot sector then error out. 438 * 439 * NOTE: 8192 is a magic size that works for ffs. 440 */ 441 error = bread(devvp, 0, 8192, NOCRED, &bp); 442 if (error) 443 goto error_exit; 444 bp->b_flags |= B_AGE; 445 bsp = (union bootsector *)bp->b_data; 446 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 447 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 448 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 449 450 #ifndef MSDOSFS_NOCHECKSIG 451 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 452 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 453 error = EINVAL; 454 goto error_exit; 455 } 456 #endif 457 458 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 459 pmp->pm_mountp = mp; 460 pmp->pm_cp = cp; 461 pmp->pm_bo = bo; 462 463 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); 464 465 /* 466 * Initialize ownerships and permissions, since nothing else will 467 * initialize them iff we are mounting root. 468 */ 469 pmp->pm_uid = UID_ROOT; 470 pmp->pm_gid = GID_WHEEL; 471 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 472 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 473 474 /* 475 * Compute several useful quantities from the bpb in the 476 * bootsector. Copy in the dos 5 variant of the bpb then fix up 477 * the fields that are different between dos 5 and dos 3.3. 478 */ 479 SecPerClust = b50->bpbSecPerClust; 480 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 481 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 482 error = EINVAL; 483 goto error_exit; 484 } 485 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 486 pmp->pm_FATs = b50->bpbFATs; 487 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 488 pmp->pm_Sectors = getushort(b50->bpbSectors); 489 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 490 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 491 pmp->pm_Heads = getushort(b50->bpbHeads); 492 pmp->pm_Media = b50->bpbMedia; 493 494 /* calculate the ratio of sector size to DEV_BSIZE */ 495 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 496 497 /* 498 * We don't check pm_Heads nor pm_SecPerTrack, because 499 * these may not be set for EFI file systems. We don't 500 * use these anyway, so we're unaffected if they are 501 * invalid. 502 */ 503 if (!pmp->pm_BytesPerSec || !SecPerClust) { 504 error = EINVAL; 505 goto error_exit; 506 } 507 508 if (pmp->pm_Sectors == 0) { 509 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 510 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 511 } else { 512 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 513 pmp->pm_HugeSectors = pmp->pm_Sectors; 514 } 515 516 if (pmp->pm_RootDirEnts == 0) { 517 if (pmp->pm_FATsecs 518 || getushort(b710->bpbFSVers)) { 519 error = EINVAL; 520 #ifdef MSDOSFS_DEBUG 521 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 522 #endif 523 goto error_exit; 524 } 525 pmp->pm_fatmask = FAT32_MASK; 526 pmp->pm_fatmult = 4; 527 pmp->pm_fatdiv = 1; 528 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 529 if (getushort(b710->bpbExtFlags) & FATMIRROR) 530 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 531 else 532 pmp->pm_flags |= MSDOSFS_FATMIRROR; 533 } else 534 pmp->pm_flags |= MSDOSFS_FATMIRROR; 535 536 /* 537 * Check a few values (could do some more): 538 * - logical sector size: power of 2, >= block size 539 * - sectors per cluster: power of 2, >= 1 540 * - number of sectors: >= 1, <= size of partition 541 * - number of FAT sectors: >= 1 542 */ 543 if ( (SecPerClust == 0) 544 || (SecPerClust & (SecPerClust - 1)) 545 || (pmp->pm_BytesPerSec < DEV_BSIZE) 546 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 547 || (pmp->pm_HugeSectors == 0) 548 || (pmp->pm_FATsecs == 0) 549 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) 550 ) { 551 error = EINVAL; 552 goto error_exit; 553 } 554 555 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 556 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 557 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 558 SecPerClust *= pmp->pm_BlkPerSec; 559 560 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 561 562 if (FAT32(pmp)) { 563 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 564 pmp->pm_firstcluster = pmp->pm_fatblk 565 + (pmp->pm_FATs * pmp->pm_FATsecs); 566 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 567 } else { 568 pmp->pm_rootdirblk = pmp->pm_fatblk + 569 (pmp->pm_FATs * pmp->pm_FATsecs); 570 pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts * 571 sizeof(struct direntry), DEV_BSIZE); /* in blocks */ 572 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 573 } 574 575 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 576 SecPerClust + 1; 577 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 578 579 if (pmp->pm_fatmask == 0) { 580 if (pmp->pm_maxcluster 581 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 582 /* 583 * This will usually be a floppy disk. This size makes 584 * sure that one FAT entry will not be split across 585 * multiple blocks. 586 */ 587 pmp->pm_fatmask = FAT12_MASK; 588 pmp->pm_fatmult = 3; 589 pmp->pm_fatdiv = 2; 590 } else { 591 pmp->pm_fatmask = FAT16_MASK; 592 pmp->pm_fatmult = 2; 593 pmp->pm_fatdiv = 1; 594 } 595 } 596 597 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 598 if (pmp->pm_maxcluster >= clusters) { 599 #ifdef MSDOSFS_DEBUG 600 printf("Warning: number of clusters (%ld) exceeds FAT " 601 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 602 #endif 603 pmp->pm_maxcluster = clusters - 1; 604 } 605 606 if (FAT12(pmp)) 607 pmp->pm_fatblocksize = 3 * 512; 608 else 609 pmp->pm_fatblocksize = PAGE_SIZE; 610 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 611 pmp->pm_BytesPerSec); 612 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 613 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 614 615 /* 616 * Compute mask and shift value for isolating cluster relative byte 617 * offsets and cluster numbers from a file offset. 618 */ 619 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 620 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 621 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 622 623 /* 624 * Check for valid cluster size 625 * must be a power of 2 626 */ 627 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 628 error = EINVAL; 629 goto error_exit; 630 } 631 632 /* 633 * Release the bootsector buffer. 634 */ 635 brelse(bp); 636 bp = NULL; 637 638 /* 639 * Check the fsinfo sector if we have one. Silently fix up our 640 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 641 * or too large. Ignore fp->fsinfree for now, since we need to 642 * read the entire FAT anyway to fill the inuse map. 643 */ 644 if (pmp->pm_fsinfo) { 645 struct fsinfo *fp; 646 647 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 648 NOCRED, &bp)) != 0) 649 goto error_exit; 650 fp = (struct fsinfo *)bp->b_data; 651 if (!bcmp(fp->fsisig1, "RRaA", 4) 652 && !bcmp(fp->fsisig2, "rrAa", 4) 653 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 654 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 655 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 656 pmp->pm_nxtfree = CLUST_FIRST; 657 } else 658 pmp->pm_fsinfo = 0; 659 brelse(bp); 660 bp = NULL; 661 } 662 663 /* 664 * Finish initializing pmp->pm_nxtfree (just in case the first few 665 * sectors aren't properly reserved in the FAT). This completes 666 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 667 * value if there is no fsinfo. We will use pmp->pm_nxtfree 668 * internally even if there is no fsinfo. 669 */ 670 if (pmp->pm_nxtfree < CLUST_FIRST) 671 pmp->pm_nxtfree = CLUST_FIRST; 672 673 /* 674 * Allocate memory for the bitmap of allocated clusters, and then 675 * fill it in. 676 */ 677 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 678 * sizeof(*pmp->pm_inusemap), 679 M_MSDOSFSFAT, M_WAITOK); 680 681 /* 682 * fillinusemap() needs pm_devvp. 683 */ 684 pmp->pm_devvp = devvp; 685 pmp->pm_dev = dev; 686 687 /* 688 * Have the inuse map filled in. 689 */ 690 MSDOSFS_LOCK_MP(pmp); 691 error = fillinusemap(pmp); 692 MSDOSFS_UNLOCK_MP(pmp); 693 if (error != 0) 694 goto error_exit; 695 696 /* 697 * If they want FAT updates to be synchronous then let them suffer 698 * the performance degradation in exchange for the on disk copy of 699 * the FAT being correct just about all the time. I suppose this 700 * would be a good thing to turn on if the kernel is still flakey. 701 */ 702 if (mp->mnt_flag & MNT_SYNCHRONOUS) 703 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 704 705 /* 706 * Finish up. 707 */ 708 if (ronly) 709 pmp->pm_flags |= MSDOSFSMNT_RONLY; 710 else { 711 if ((error = markvoldirty(pmp, 1)) != 0) 712 goto error_exit; 713 pmp->pm_fmod = 1; 714 } 715 mp->mnt_data = pmp; 716 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 717 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 718 MNT_ILOCK(mp); 719 mp->mnt_flag |= MNT_LOCAL; 720 mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF; 721 MNT_IUNLOCK(mp); 722 723 return (0); 724 725 error_exit: 726 if (bp) 727 brelse(bp); 728 if (cp != NULL) { 729 g_topology_lock(); 730 g_vfs_close(cp); 731 g_topology_unlock(); 732 } 733 if (pmp) { 734 lockdestroy(&pmp->pm_fatlock); 735 free(pmp->pm_inusemap, M_MSDOSFSFAT); 736 free(pmp, M_MSDOSFSMNT); 737 mp->mnt_data = NULL; 738 } 739 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 740 dev_rel(dev); 741 return (error); 742 } 743 744 /* 745 * Unmount the filesystem described by mp. 746 */ 747 static int 748 msdosfs_unmount(struct mount *mp, int mntflags) 749 { 750 struct msdosfsmount *pmp; 751 int error, flags; 752 753 error = flags = 0; 754 pmp = VFSTOMSDOSFS(mp); 755 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) 756 error = msdosfs_sync(mp, MNT_WAIT); 757 if ((mntflags & MNT_FORCE) != 0) 758 flags |= FORCECLOSE; 759 else if (error != 0) 760 return (error); 761 error = vflush(mp, 0, flags, curthread); 762 if (error != 0 && error != ENXIO) 763 return (error); 764 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 765 error = markvoldirty(pmp, 0); 766 if (error && error != ENXIO) { 767 (void)markvoldirty(pmp, 1); 768 return (error); 769 } 770 } 771 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 772 if (pmp->pm_w2u) 773 msdosfs_iconv->close(pmp->pm_w2u); 774 if (pmp->pm_u2w) 775 msdosfs_iconv->close(pmp->pm_u2w); 776 if (pmp->pm_d2u) 777 msdosfs_iconv->close(pmp->pm_d2u); 778 if (pmp->pm_u2d) 779 msdosfs_iconv->close(pmp->pm_u2d); 780 } 781 782 #ifdef MSDOSFS_DEBUG 783 { 784 struct vnode *vp = pmp->pm_devvp; 785 struct bufobj *bo; 786 787 bo = &vp->v_bufobj; 788 BO_LOCK(bo); 789 VI_LOCK(vp); 790 vn_printf(vp, 791 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 792 printf("freef %p, freeb %p, mount %p\n", 793 TAILQ_NEXT(vp, v_vnodelist), vp->v_vnodelist.tqe_prev, 794 vp->v_mount); 795 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 796 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 797 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 798 vp->v_bufobj.bo_numoutput, vp->v_type); 799 VI_UNLOCK(vp); 800 BO_UNLOCK(bo); 801 } 802 #endif 803 g_topology_lock(); 804 g_vfs_close(pmp->pm_cp); 805 g_topology_unlock(); 806 atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0); 807 vrele(pmp->pm_devvp); 808 dev_rel(pmp->pm_dev); 809 free(pmp->pm_inusemap, M_MSDOSFSFAT); 810 lockdestroy(&pmp->pm_fatlock); 811 free(pmp, M_MSDOSFSMNT); 812 mp->mnt_data = NULL; 813 MNT_ILOCK(mp); 814 mp->mnt_flag &= ~MNT_LOCAL; 815 MNT_IUNLOCK(mp); 816 return (error); 817 } 818 819 static int 820 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 821 { 822 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 823 struct denode *ndep; 824 int error; 825 826 #ifdef MSDOSFS_DEBUG 827 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 828 #endif 829 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 830 if (error) 831 return (error); 832 *vpp = DETOV(ndep); 833 return (0); 834 } 835 836 static int 837 msdosfs_statfs(struct mount *mp, struct statfs *sbp) 838 { 839 struct msdosfsmount *pmp; 840 841 pmp = VFSTOMSDOSFS(mp); 842 sbp->f_bsize = pmp->pm_bpcluster; 843 sbp->f_iosize = pmp->pm_bpcluster; 844 sbp->f_blocks = pmp->pm_maxcluster + 1; 845 sbp->f_bfree = pmp->pm_freeclustercount; 846 sbp->f_bavail = pmp->pm_freeclustercount; 847 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 848 sbp->f_ffree = 0; /* what to put in here? */ 849 return (0); 850 } 851 852 /* 853 * If we have an FSInfo block, update it. 854 */ 855 static int 856 msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) 857 { 858 struct fsinfo *fp; 859 struct buf *bp; 860 int error; 861 862 MSDOSFS_LOCK_MP(pmp); 863 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { 864 error = 0; 865 goto unlock; 866 } 867 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 868 NOCRED, &bp); 869 if (error != 0) { 870 goto unlock; 871 } 872 fp = (struct fsinfo *)bp->b_data; 873 putulong(fp->fsinfree, pmp->pm_freeclustercount); 874 putulong(fp->fsinxtfree, pmp->pm_nxtfree); 875 pmp->pm_flags &= ~MSDOSFS_FSIMOD; 876 if (waitfor == MNT_WAIT) 877 error = bwrite(bp); 878 else 879 bawrite(bp); 880 unlock: 881 MSDOSFS_UNLOCK_MP(pmp); 882 return (error); 883 } 884 885 static int 886 msdosfs_sync(struct mount *mp, int waitfor) 887 { 888 struct vnode *vp, *nvp; 889 struct thread *td; 890 struct denode *dep; 891 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 892 int error, allerror = 0; 893 894 td = curthread; 895 896 /* 897 * If we ever switch to not updating all of the FATs all the time, 898 * this would be the place to update them from the first one. 899 */ 900 if (pmp->pm_fmod != 0) { 901 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 902 panic("msdosfs_sync: rofs mod"); 903 else { 904 /* update FATs here */ 905 } 906 } 907 /* 908 * Write back each (modified) denode. 909 */ 910 loop: 911 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { 912 if (vp->v_type == VNON) { 913 VI_UNLOCK(vp); 914 continue; 915 } 916 dep = VTODE(vp); 917 if ((dep->de_flag & 918 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 919 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 920 waitfor == MNT_LAZY)) { 921 VI_UNLOCK(vp); 922 continue; 923 } 924 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 925 if (error) { 926 if (error == ENOENT) { 927 MNT_VNODE_FOREACH_ALL_ABORT(mp, nvp); 928 goto loop; 929 } 930 continue; 931 } 932 error = VOP_FSYNC(vp, waitfor, td); 933 if (error) 934 allerror = error; 935 VOP_UNLOCK(vp); 936 vrele(vp); 937 } 938 939 /* 940 * Flush filesystem control info. 941 */ 942 if (waitfor != MNT_LAZY) { 943 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 944 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 945 if (error) 946 allerror = error; 947 VOP_UNLOCK(pmp->pm_devvp); 948 } 949 950 error = msdosfs_fsiflush(pmp, waitfor); 951 if (error != 0) 952 allerror = error; 953 return (allerror); 954 } 955 956 static int 957 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) 958 { 959 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 960 struct defid *defhp = (struct defid *) fhp; 961 struct denode *dep; 962 int error; 963 964 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 965 if (error) { 966 *vpp = NULLVP; 967 return (error); 968 } 969 *vpp = DETOV(dep); 970 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 971 return (0); 972 } 973 974 static struct vfsops msdosfs_vfsops = { 975 .vfs_fhtovp = msdosfs_fhtovp, 976 .vfs_mount = msdosfs_mount, 977 .vfs_cmount = msdosfs_cmount, 978 .vfs_root = msdosfs_root, 979 .vfs_statfs = msdosfs_statfs, 980 .vfs_sync = msdosfs_sync, 981 .vfs_unmount = msdosfs_unmount, 982 }; 983 984 VFS_SET(msdosfs_vfsops, msdosfs, 0); 985 MODULE_VERSION(msdosfs, 1); 986