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 struct export_args exp; 194 int error; 195 196 if (data == NULL) 197 return (EINVAL); 198 error = copyin(data, &args, sizeof args); 199 if (error) 200 return (error); 201 vfs_oexport_conv(&args.export, &exp); 202 203 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 204 ma = mount_arg(ma, "export", &exp, sizeof(exp)); 205 ma = mount_argf(ma, "uid", "%d", args.uid); 206 ma = mount_argf(ma, "gid", "%d", args.gid); 207 ma = mount_argf(ma, "mask", "%d", args.mask); 208 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 209 210 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 211 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 212 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 213 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 214 215 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 216 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 217 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 218 219 error = kernel_mount(ma, flags); 220 221 return (error); 222 } 223 224 /* 225 * mp - path - addr in user space of mount point (ie /usr or whatever) 226 * data - addr in user space of mount params including the name of the block 227 * special file to treat as a filesystem. 228 */ 229 static int 230 msdosfs_mount(struct mount *mp) 231 { 232 struct vnode *devvp; /* vnode for blk device to mount */ 233 struct thread *td; 234 /* msdosfs specific mount control block */ 235 struct msdosfsmount *pmp = NULL; 236 struct nameidata ndp; 237 int error, flags; 238 accmode_t accmode; 239 char *from; 240 241 td = curthread; 242 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 243 return (EINVAL); 244 245 /* 246 * If updating, check whether changing from read-only to 247 * read/write; if there is no device name, that's all we do. 248 */ 249 if (mp->mnt_flag & MNT_UPDATE) { 250 pmp = VFSTOMSDOSFS(mp); 251 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 252 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 253 error = VFS_SYNC(mp, MNT_WAIT); 254 if (error) 255 return (error); 256 flags = WRITECLOSE; 257 if (mp->mnt_flag & MNT_FORCE) 258 flags |= FORCECLOSE; 259 error = vflush(mp, 0, flags, td); 260 if (error) 261 return (error); 262 263 /* 264 * Now the volume is clean. Mark it so while the 265 * device is still rw. 266 */ 267 error = markvoldirty(pmp, 0); 268 if (error) { 269 (void)markvoldirty(pmp, 1); 270 return (error); 271 } 272 273 /* Downgrade the device from rw to ro. */ 274 g_topology_lock(); 275 error = g_access(pmp->pm_cp, 0, -1, 0); 276 g_topology_unlock(); 277 if (error) { 278 (void)markvoldirty(pmp, 1); 279 return (error); 280 } 281 282 /* 283 * Backing out after an error was painful in the 284 * above. Now we are committed to succeeding. 285 */ 286 pmp->pm_fmod = 0; 287 pmp->pm_flags |= MSDOSFSMNT_RONLY; 288 MNT_ILOCK(mp); 289 mp->mnt_flag |= MNT_RDONLY; 290 MNT_IUNLOCK(mp); 291 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 292 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 293 /* 294 * If upgrade to read-write by non-root, then verify 295 * that user has necessary permissions on the device. 296 */ 297 devvp = pmp->pm_devvp; 298 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 299 error = VOP_ACCESS(devvp, VREAD | VWRITE, 300 td->td_ucred, td); 301 if (error) 302 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 303 if (error) { 304 VOP_UNLOCK(devvp); 305 return (error); 306 } 307 VOP_UNLOCK(devvp); 308 g_topology_lock(); 309 error = g_access(pmp->pm_cp, 0, 1, 0); 310 g_topology_unlock(); 311 if (error) 312 return (error); 313 314 /* Now that the volume is modifiable, mark it dirty. */ 315 error = markvoldirty_upgrade(pmp, true, true); 316 if (error) { 317 /* 318 * If dirtying the superblock failed, drop GEOM 319 * 'w' refs (we're still RO). 320 */ 321 g_topology_lock(); 322 (void)g_access(pmp->pm_cp, 0, -1, 0); 323 g_topology_unlock(); 324 325 return (error); 326 } 327 328 pmp->pm_fmod = 1; 329 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 330 MNT_ILOCK(mp); 331 mp->mnt_flag &= ~MNT_RDONLY; 332 MNT_IUNLOCK(mp); 333 } 334 } 335 /* 336 * Not an update, or updating the name: look up the name 337 * and verify that it refers to a sensible disk device. 338 */ 339 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 340 return (EINVAL); 341 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 342 error = namei(&ndp); 343 if (error) 344 return (error); 345 devvp = ndp.ni_vp; 346 NDFREE(&ndp, NDF_ONLY_PNBUF); 347 348 if (!vn_isdisk(devvp, &error)) { 349 vput(devvp); 350 return (error); 351 } 352 /* 353 * If mount by non-root, then verify that user has necessary 354 * permissions on the device. 355 */ 356 accmode = VREAD; 357 if ((mp->mnt_flag & MNT_RDONLY) == 0) 358 accmode |= VWRITE; 359 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 360 if (error) 361 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 362 if (error) { 363 vput(devvp); 364 return (error); 365 } 366 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 367 error = mountmsdosfs(devvp, mp); 368 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 369 pmp = VFSTOMSDOSFS(mp); 370 #endif 371 } else { 372 vput(devvp); 373 if (devvp != pmp->pm_devvp) 374 return (EINVAL); /* XXX needs translation */ 375 } 376 if (error) { 377 vrele(devvp); 378 return (error); 379 } 380 381 error = update_mp(mp, td); 382 if (error) { 383 if ((mp->mnt_flag & MNT_UPDATE) == 0) 384 msdosfs_unmount(mp, MNT_FORCE); 385 return error; 386 } 387 388 vfs_mountedfrom(mp, from); 389 #ifdef MSDOSFS_DEBUG 390 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 391 #endif 392 return (0); 393 } 394 395 static int 396 mountmsdosfs(struct vnode *devvp, struct mount *mp) 397 { 398 struct msdosfsmount *pmp; 399 struct buf *bp; 400 struct cdev *dev; 401 union bootsector *bsp; 402 struct byte_bpb33 *b33; 403 struct byte_bpb50 *b50; 404 struct byte_bpb710 *b710; 405 uint8_t SecPerClust; 406 u_long clusters; 407 int ronly, error; 408 struct g_consumer *cp; 409 struct bufobj *bo; 410 411 bp = NULL; /* This and pmp both used in error_exit. */ 412 pmp = NULL; 413 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 414 415 dev = devvp->v_rdev; 416 if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0, 417 (uintptr_t)mp) == 0) { 418 VOP_UNLOCK(devvp); 419 return (EBUSY); 420 } 421 g_topology_lock(); 422 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 423 g_topology_unlock(); 424 if (error != 0) { 425 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 426 VOP_UNLOCK(devvp); 427 return (error); 428 } 429 dev_ref(dev); 430 bo = &devvp->v_bufobj; 431 VOP_UNLOCK(devvp); 432 if (dev->si_iosize_max != 0) 433 mp->mnt_iosize_max = dev->si_iosize_max; 434 if (mp->mnt_iosize_max > MAXPHYS) 435 mp->mnt_iosize_max = MAXPHYS; 436 437 /* 438 * Read the boot sector of the filesystem, and then check the 439 * boot signature. If not a dos boot sector then error out. 440 * 441 * NOTE: 8192 is a magic size that works for ffs. 442 */ 443 error = bread(devvp, 0, 8192, NOCRED, &bp); 444 if (error) 445 goto error_exit; 446 bp->b_flags |= B_AGE; 447 bsp = (union bootsector *)bp->b_data; 448 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 449 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 450 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 451 452 #ifndef MSDOSFS_NOCHECKSIG 453 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 454 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 455 error = EINVAL; 456 goto error_exit; 457 } 458 #endif 459 460 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 461 pmp->pm_mountp = mp; 462 pmp->pm_cp = cp; 463 pmp->pm_bo = bo; 464 465 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); 466 467 /* 468 * Initialize ownerships and permissions, since nothing else will 469 * initialize them iff we are mounting root. 470 */ 471 pmp->pm_uid = UID_ROOT; 472 pmp->pm_gid = GID_WHEEL; 473 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 474 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 475 476 /* 477 * Compute several useful quantities from the bpb in the 478 * bootsector. Copy in the dos 5 variant of the bpb then fix up 479 * the fields that are different between dos 5 and dos 3.3. 480 */ 481 SecPerClust = b50->bpbSecPerClust; 482 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 483 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 484 error = EINVAL; 485 goto error_exit; 486 } 487 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 488 pmp->pm_FATs = b50->bpbFATs; 489 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 490 pmp->pm_Sectors = getushort(b50->bpbSectors); 491 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 492 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 493 pmp->pm_Heads = getushort(b50->bpbHeads); 494 pmp->pm_Media = b50->bpbMedia; 495 496 /* calculate the ratio of sector size to DEV_BSIZE */ 497 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 498 499 /* 500 * We don't check pm_Heads nor pm_SecPerTrack, because 501 * these may not be set for EFI file systems. We don't 502 * use these anyway, so we're unaffected if they are 503 * invalid. 504 */ 505 if (!pmp->pm_BytesPerSec || !SecPerClust) { 506 error = EINVAL; 507 goto error_exit; 508 } 509 510 if (pmp->pm_Sectors == 0) { 511 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 512 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 513 } else { 514 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 515 pmp->pm_HugeSectors = pmp->pm_Sectors; 516 } 517 518 if (pmp->pm_RootDirEnts == 0) { 519 if (pmp->pm_FATsecs 520 || getushort(b710->bpbFSVers)) { 521 error = EINVAL; 522 #ifdef MSDOSFS_DEBUG 523 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 524 #endif 525 goto error_exit; 526 } 527 pmp->pm_fatmask = FAT32_MASK; 528 pmp->pm_fatmult = 4; 529 pmp->pm_fatdiv = 1; 530 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 531 if (getushort(b710->bpbExtFlags) & FATMIRROR) 532 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 533 else 534 pmp->pm_flags |= MSDOSFS_FATMIRROR; 535 } else 536 pmp->pm_flags |= MSDOSFS_FATMIRROR; 537 538 /* 539 * Check a few values (could do some more): 540 * - logical sector size: power of 2, >= block size 541 * - sectors per cluster: power of 2, >= 1 542 * - number of sectors: >= 1, <= size of partition 543 * - number of FAT sectors: >= 1 544 */ 545 if ( (SecPerClust == 0) 546 || (SecPerClust & (SecPerClust - 1)) 547 || (pmp->pm_BytesPerSec < DEV_BSIZE) 548 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 549 || (pmp->pm_HugeSectors == 0) 550 || (pmp->pm_FATsecs == 0) 551 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) 552 ) { 553 error = EINVAL; 554 goto error_exit; 555 } 556 557 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 558 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 559 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 560 SecPerClust *= pmp->pm_BlkPerSec; 561 562 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 563 564 if (FAT32(pmp)) { 565 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 566 pmp->pm_firstcluster = pmp->pm_fatblk 567 + (pmp->pm_FATs * pmp->pm_FATsecs); 568 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 569 } else { 570 pmp->pm_rootdirblk = pmp->pm_fatblk + 571 (pmp->pm_FATs * pmp->pm_FATsecs); 572 pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts * 573 sizeof(struct direntry), DEV_BSIZE); /* in blocks */ 574 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 575 } 576 577 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 578 SecPerClust + 1; 579 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 580 581 if (pmp->pm_fatmask == 0) { 582 if (pmp->pm_maxcluster 583 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 584 /* 585 * This will usually be a floppy disk. This size makes 586 * sure that one FAT entry will not be split across 587 * multiple blocks. 588 */ 589 pmp->pm_fatmask = FAT12_MASK; 590 pmp->pm_fatmult = 3; 591 pmp->pm_fatdiv = 2; 592 } else { 593 pmp->pm_fatmask = FAT16_MASK; 594 pmp->pm_fatmult = 2; 595 pmp->pm_fatdiv = 1; 596 } 597 } 598 599 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 600 if (pmp->pm_maxcluster >= clusters) { 601 #ifdef MSDOSFS_DEBUG 602 printf("Warning: number of clusters (%ld) exceeds FAT " 603 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 604 #endif 605 pmp->pm_maxcluster = clusters - 1; 606 } 607 608 if (FAT12(pmp)) 609 pmp->pm_fatblocksize = 3 * 512; 610 else 611 pmp->pm_fatblocksize = PAGE_SIZE; 612 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 613 pmp->pm_BytesPerSec); 614 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 615 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 616 617 /* 618 * Compute mask and shift value for isolating cluster relative byte 619 * offsets and cluster numbers from a file offset. 620 */ 621 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 622 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 623 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 624 625 /* 626 * Check for valid cluster size 627 * must be a power of 2 628 */ 629 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 630 error = EINVAL; 631 goto error_exit; 632 } 633 634 /* 635 * Release the bootsector buffer. 636 */ 637 brelse(bp); 638 bp = NULL; 639 640 /* 641 * Check the fsinfo sector if we have one. Silently fix up our 642 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 643 * or too large. Ignore fp->fsinfree for now, since we need to 644 * read the entire FAT anyway to fill the inuse map. 645 */ 646 if (pmp->pm_fsinfo) { 647 struct fsinfo *fp; 648 649 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 650 NOCRED, &bp)) != 0) 651 goto error_exit; 652 fp = (struct fsinfo *)bp->b_data; 653 if (!bcmp(fp->fsisig1, "RRaA", 4) 654 && !bcmp(fp->fsisig2, "rrAa", 4) 655 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 656 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 657 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 658 pmp->pm_nxtfree = CLUST_FIRST; 659 } else 660 pmp->pm_fsinfo = 0; 661 brelse(bp); 662 bp = NULL; 663 } 664 665 /* 666 * Finish initializing pmp->pm_nxtfree (just in case the first few 667 * sectors aren't properly reserved in the FAT). This completes 668 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 669 * value if there is no fsinfo. We will use pmp->pm_nxtfree 670 * internally even if there is no fsinfo. 671 */ 672 if (pmp->pm_nxtfree < CLUST_FIRST) 673 pmp->pm_nxtfree = CLUST_FIRST; 674 675 /* 676 * Allocate memory for the bitmap of allocated clusters, and then 677 * fill it in. 678 */ 679 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 680 * sizeof(*pmp->pm_inusemap), 681 M_MSDOSFSFAT, M_WAITOK); 682 683 /* 684 * fillinusemap() needs pm_devvp. 685 */ 686 pmp->pm_devvp = devvp; 687 pmp->pm_dev = dev; 688 689 /* 690 * Have the inuse map filled in. 691 */ 692 MSDOSFS_LOCK_MP(pmp); 693 error = fillinusemap(pmp); 694 MSDOSFS_UNLOCK_MP(pmp); 695 if (error != 0) 696 goto error_exit; 697 698 /* 699 * If they want FAT updates to be synchronous then let them suffer 700 * the performance degradation in exchange for the on disk copy of 701 * the FAT being correct just about all the time. I suppose this 702 * would be a good thing to turn on if the kernel is still flakey. 703 */ 704 if (mp->mnt_flag & MNT_SYNCHRONOUS) 705 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 706 707 /* 708 * Finish up. 709 */ 710 if (ronly) 711 pmp->pm_flags |= MSDOSFSMNT_RONLY; 712 else { 713 if ((error = markvoldirty(pmp, 1)) != 0) 714 goto error_exit; 715 pmp->pm_fmod = 1; 716 } 717 mp->mnt_data = pmp; 718 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 719 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 720 MNT_ILOCK(mp); 721 mp->mnt_flag |= MNT_LOCAL; 722 mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF; 723 MNT_IUNLOCK(mp); 724 725 return (0); 726 727 error_exit: 728 if (bp) 729 brelse(bp); 730 if (cp != NULL) { 731 g_topology_lock(); 732 g_vfs_close(cp); 733 g_topology_unlock(); 734 } 735 if (pmp) { 736 lockdestroy(&pmp->pm_fatlock); 737 free(pmp->pm_inusemap, M_MSDOSFSFAT); 738 free(pmp, M_MSDOSFSMNT); 739 mp->mnt_data = NULL; 740 } 741 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 742 dev_rel(dev); 743 return (error); 744 } 745 746 /* 747 * Unmount the filesystem described by mp. 748 */ 749 static int 750 msdosfs_unmount(struct mount *mp, int mntflags) 751 { 752 struct msdosfsmount *pmp; 753 int error, flags; 754 755 error = flags = 0; 756 pmp = VFSTOMSDOSFS(mp); 757 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) 758 error = msdosfs_sync(mp, MNT_WAIT); 759 if ((mntflags & MNT_FORCE) != 0) 760 flags |= FORCECLOSE; 761 else if (error != 0) 762 return (error); 763 error = vflush(mp, 0, flags, curthread); 764 if (error != 0 && error != ENXIO) 765 return (error); 766 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 767 error = markvoldirty(pmp, 0); 768 if (error && error != ENXIO) { 769 (void)markvoldirty(pmp, 1); 770 return (error); 771 } 772 } 773 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 774 if (pmp->pm_w2u) 775 msdosfs_iconv->close(pmp->pm_w2u); 776 if (pmp->pm_u2w) 777 msdosfs_iconv->close(pmp->pm_u2w); 778 if (pmp->pm_d2u) 779 msdosfs_iconv->close(pmp->pm_d2u); 780 if (pmp->pm_u2d) 781 msdosfs_iconv->close(pmp->pm_u2d); 782 } 783 784 #ifdef MSDOSFS_DEBUG 785 { 786 struct vnode *vp = pmp->pm_devvp; 787 struct bufobj *bo; 788 789 bo = &vp->v_bufobj; 790 BO_LOCK(bo); 791 VI_LOCK(vp); 792 vn_printf(vp, 793 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 794 printf("freef %p, freeb %p, mount %p\n", 795 TAILQ_NEXT(vp, v_vnodelist), vp->v_vnodelist.tqe_prev, 796 vp->v_mount); 797 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 798 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 799 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 800 vp->v_bufobj.bo_numoutput, vp->v_type); 801 VI_UNLOCK(vp); 802 BO_UNLOCK(bo); 803 } 804 #endif 805 g_topology_lock(); 806 g_vfs_close(pmp->pm_cp); 807 g_topology_unlock(); 808 atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0); 809 vrele(pmp->pm_devvp); 810 dev_rel(pmp->pm_dev); 811 free(pmp->pm_inusemap, M_MSDOSFSFAT); 812 lockdestroy(&pmp->pm_fatlock); 813 free(pmp, M_MSDOSFSMNT); 814 mp->mnt_data = NULL; 815 MNT_ILOCK(mp); 816 mp->mnt_flag &= ~MNT_LOCAL; 817 MNT_IUNLOCK(mp); 818 return (error); 819 } 820 821 static int 822 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 823 { 824 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 825 struct denode *ndep; 826 int error; 827 828 #ifdef MSDOSFS_DEBUG 829 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 830 #endif 831 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 832 if (error) 833 return (error); 834 *vpp = DETOV(ndep); 835 return (0); 836 } 837 838 static int 839 msdosfs_statfs(struct mount *mp, struct statfs *sbp) 840 { 841 struct msdosfsmount *pmp; 842 843 pmp = VFSTOMSDOSFS(mp); 844 sbp->f_bsize = pmp->pm_bpcluster; 845 sbp->f_iosize = pmp->pm_bpcluster; 846 sbp->f_blocks = pmp->pm_maxcluster + 1; 847 sbp->f_bfree = pmp->pm_freeclustercount; 848 sbp->f_bavail = pmp->pm_freeclustercount; 849 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 850 sbp->f_ffree = 0; /* what to put in here? */ 851 return (0); 852 } 853 854 /* 855 * If we have an FSInfo block, update it. 856 */ 857 static int 858 msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) 859 { 860 struct fsinfo *fp; 861 struct buf *bp; 862 int error; 863 864 MSDOSFS_LOCK_MP(pmp); 865 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { 866 error = 0; 867 goto unlock; 868 } 869 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 870 NOCRED, &bp); 871 if (error != 0) { 872 goto unlock; 873 } 874 fp = (struct fsinfo *)bp->b_data; 875 putulong(fp->fsinfree, pmp->pm_freeclustercount); 876 putulong(fp->fsinxtfree, pmp->pm_nxtfree); 877 pmp->pm_flags &= ~MSDOSFS_FSIMOD; 878 if (waitfor == MNT_WAIT) 879 error = bwrite(bp); 880 else 881 bawrite(bp); 882 unlock: 883 MSDOSFS_UNLOCK_MP(pmp); 884 return (error); 885 } 886 887 static int 888 msdosfs_sync(struct mount *mp, int waitfor) 889 { 890 struct vnode *vp, *nvp; 891 struct thread *td; 892 struct denode *dep; 893 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 894 int error, allerror = 0; 895 896 td = curthread; 897 898 /* 899 * If we ever switch to not updating all of the FATs all the time, 900 * this would be the place to update them from the first one. 901 */ 902 if (pmp->pm_fmod != 0) { 903 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 904 panic("msdosfs_sync: rofs mod"); 905 else { 906 /* update FATs here */ 907 } 908 } 909 /* 910 * Write back each (modified) denode. 911 */ 912 loop: 913 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { 914 if (vp->v_type == VNON) { 915 VI_UNLOCK(vp); 916 continue; 917 } 918 dep = VTODE(vp); 919 if ((dep->de_flag & 920 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 921 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 922 waitfor == MNT_LAZY)) { 923 VI_UNLOCK(vp); 924 continue; 925 } 926 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 927 if (error) { 928 if (error == ENOENT) { 929 MNT_VNODE_FOREACH_ALL_ABORT(mp, nvp); 930 goto loop; 931 } 932 continue; 933 } 934 error = VOP_FSYNC(vp, waitfor, td); 935 if (error) 936 allerror = error; 937 VOP_UNLOCK(vp); 938 vrele(vp); 939 } 940 941 /* 942 * Flush filesystem control info. 943 */ 944 if (waitfor != MNT_LAZY) { 945 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 946 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 947 if (error) 948 allerror = error; 949 VOP_UNLOCK(pmp->pm_devvp); 950 } 951 952 error = msdosfs_fsiflush(pmp, waitfor); 953 if (error != 0) 954 allerror = error; 955 return (allerror); 956 } 957 958 static int 959 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) 960 { 961 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 962 struct defid *defhp = (struct defid *) fhp; 963 struct denode *dep; 964 int error; 965 966 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 967 if (error) { 968 *vpp = NULLVP; 969 return (error); 970 } 971 *vpp = DETOV(dep); 972 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 973 return (0); 974 } 975 976 static struct vfsops msdosfs_vfsops = { 977 .vfs_fhtovp = msdosfs_fhtovp, 978 .vfs_mount = msdosfs_mount, 979 .vfs_cmount = msdosfs_cmount, 980 .vfs_root = msdosfs_root, 981 .vfs_statfs = msdosfs_statfs, 982 .vfs_sync = msdosfs_sync, 983 .vfs_unmount = msdosfs_unmount, 984 }; 985 986 VFS_SET(msdosfs_vfsops, msdosfs, 0); 987 MODULE_VERSION(msdosfs, 1); 988