msdosfs_vfsops.c revision 173690
1/* $FreeBSD: head/sys/fs/msdosfs/msdosfs_vfsops.c 173690 2007-11-17 16:19:48Z maxim $ */ 2/* $NetBSD: msdosfs_vfsops.c,v 1.51 1997/11/17 15:36:58 ws Exp $ */ 3 4/*- 5 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. 6 * Copyright (C) 1994, 1995, 1997 TooLs GmbH. 7 * All rights reserved. 8 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by TooLs GmbH. 21 * 4. The name of TooLs GmbH may not be used to endorse or promote products 22 * derived from this software without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 27 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 29 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 30 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 32 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 33 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35/*- 36 * Written by Paul Popelka (paulp@uts.amdahl.com) 37 * 38 * You can do anything you want with this software, just don't say you wrote 39 * it, and don't remove this notice. 40 * 41 * This software is provided "as is". 42 * 43 * The author supplies this software to be publicly redistributed on the 44 * understanding that the author is not responsible for the correct 45 * functioning of this software in any circumstances and is not liable for 46 * any damages caused by this software. 47 * 48 * October 1992 49 */ 50 51#include <sys/param.h> 52#include <sys/systm.h> 53#include <sys/buf.h> 54#include <sys/conf.h> 55#include <sys/iconv.h> 56#include <sys/kernel.h> 57#include <sys/lock.h> 58#include <sys/malloc.h> 59#include <sys/mount.h> 60#include <sys/mutex.h> 61#include <sys/namei.h> 62#include <sys/priv.h> 63#include <sys/proc.h> 64#include <sys/stat.h> 65#include <sys/vnode.h> 66 67#include <geom/geom.h> 68#include <geom/geom_vfs.h> 69 70#include <fs/msdosfs/bootsect.h> 71#include <fs/msdosfs/bpb.h> 72#include <fs/msdosfs/direntry.h> 73#include <fs/msdosfs/denode.h> 74#include <fs/msdosfs/fat.h> 75#include <fs/msdosfs/msdosfsmount.h> 76 77/* Mount options that we support. */ 78static const char *msdosfs_opts[] = { 79 "async", "noatime", "noclusterr", "noclusterw", 80 "export", "force", "from", "sync", 81 "cs_dos", "cs_local", "cs_win", "dirmask", 82 "gid", "kiconv", "large", "longname", 83 "longnames", "mask", "shortname", "shortnames", 84 "uid", "win95", "nowin95", 85 NULL 86}; 87 88#if 1 /*def PC98*/ 89/* 90 * XXX - The boot signature formatted by NEC PC-98 DOS looks like a 91 * garbage or a random value :-{ 92 * If you want to use that broken-signatured media, define the 93 * following symbol even though PC/AT. 94 * (ex. mount PC-98 DOS formatted FD on PC/AT) 95 */ 96#define MSDOSFS_NOCHECKSIG 97#endif 98 99MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); 100static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); 101 102struct iconv_functions *msdosfs_iconv; 103 104static int update_mp(struct mount *mp, struct thread *td); 105static int mountmsdosfs(struct vnode *devvp, struct mount *mp, 106 struct thread *td); 107static vfs_fhtovp_t msdosfs_fhtovp; 108static vfs_mount_t msdosfs_mount; 109static vfs_root_t msdosfs_root; 110static vfs_statfs_t msdosfs_statfs; 111static vfs_sync_t msdosfs_sync; 112static vfs_unmount_t msdosfs_unmount; 113 114/* Maximum length of a character set name (arbitrary). */ 115#define MAXCSLEN 64 116 117static int 118update_mp(struct mount *mp, struct thread *td) 119{ 120 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 121 void *dos, *win, *local; 122 int error, v; 123 124 if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { 125 if (msdosfs_iconv != NULL) { 126 error = vfs_getopt(mp->mnt_optnew, 127 "cs_win", &win, NULL); 128 if (!error) 129 error = vfs_getopt(mp->mnt_optnew, 130 "cs_local", &local, NULL); 131 if (!error) 132 error = vfs_getopt(mp->mnt_optnew, 133 "cs_dos", &dos, NULL); 134 if (!error) { 135 msdosfs_iconv->open(win, local, &pmp->pm_u2w); 136 msdosfs_iconv->open(local, win, &pmp->pm_w2u); 137 msdosfs_iconv->open(dos, local, &pmp->pm_u2d); 138 msdosfs_iconv->open(local, dos, &pmp->pm_d2u); 139 } 140 if (error != 0) 141 return (error); 142 } else { 143 pmp->pm_w2u = NULL; 144 pmp->pm_u2w = NULL; 145 pmp->pm_d2u = NULL; 146 pmp->pm_u2d = NULL; 147 } 148 } 149 150 if (1 == vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v)) 151 pmp->pm_gid = v; 152 if (1 == vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v)) 153 pmp->pm_uid = v; 154 if (1 == vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v)) 155 pmp->pm_mask = v & ALLPERMS; 156 if (1 == vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v)) 157 pmp->pm_dirmask = v & ALLPERMS; 158 vfs_flagopt(mp->mnt_optnew, "shortname", 159 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 160 vfs_flagopt(mp->mnt_optnew, "shortnames", 161 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 162 vfs_flagopt(mp->mnt_optnew, "longname", 163 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 164 vfs_flagopt(mp->mnt_optnew, "longnames", 165 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 166 vfs_flagopt(mp->mnt_optnew, "kiconv", 167 &pmp->pm_flags, MSDOSFSMNT_KICONV); 168 169 if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) 170 pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 171 else 172 pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; 173 174 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 175 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 176 else if (!(pmp->pm_flags & 177 (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) { 178 struct vnode *rootvp; 179 180 /* 181 * Try to divine whether to support Win'95 long filenames 182 */ 183 if (FAT32(pmp)) 184 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 185 else { 186 if ((error = 187 msdosfs_root(mp, LK_EXCLUSIVE, &rootvp, td)) != 0) 188 return error; 189 pmp->pm_flags |= findwin95(VTODE(rootvp)) ? 190 MSDOSFSMNT_LONGNAME : MSDOSFSMNT_SHORTNAME; 191 vput(rootvp); 192 } 193 } 194 return 0; 195} 196 197static int 198msdosfs_cmount(struct mntarg *ma, void *data, int flags, struct thread *td) 199{ 200 struct msdosfs_args args; 201 int error; 202 203 if (data == NULL) 204 return (EINVAL); 205 error = copyin(data, &args, sizeof args); 206 if (error) 207 return (error); 208 209 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 210 ma = mount_arg(ma, "export", &args.export, sizeof args.export); 211 ma = mount_argf(ma, "uid", "%d", args.uid); 212 ma = mount_argf(ma, "gid", "%d", args.gid); 213 ma = mount_argf(ma, "mask", "%d", args.mask); 214 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 215 216 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 217 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 218 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 219 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 220 221 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 222 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 223 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 224 225 error = kernel_mount(ma, flags); 226 227 return (error); 228} 229 230/* 231 * mp - path - addr in user space of mount point (ie /usr or whatever) 232 * data - addr in user space of mount params including the name of the block 233 * special file to treat as a filesystem. 234 */ 235static int 236msdosfs_mount(struct mount *mp, struct thread *td) 237{ 238 struct vnode *devvp; /* vnode for blk device to mount */ 239 /* msdosfs specific mount control block */ 240 struct msdosfsmount *pmp = NULL; 241 struct nameidata ndp; 242 int error, flags; 243 mode_t accessmode; 244 char *from; 245 246 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 247 return (EINVAL); 248 249 /* 250 * If updating, check whether changing from read-only to 251 * read/write; if there is no device name, that's all we do. 252 */ 253 if (mp->mnt_flag & MNT_UPDATE) { 254 pmp = VFSTOMSDOSFS(mp); 255 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) { 256 /* 257 * Forbid export requests if filesystem has 258 * MSDOSFS_LARGEFS flag set. 259 */ 260 if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) { 261 vfs_mount_error(mp, 262 "MSDOSFS_LARGEFS flag set, cannot export"); 263 return (EOPNOTSUPP); 264 } 265 } 266 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 267 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 268 error = VFS_SYNC(mp, MNT_WAIT, td); 269 if (error) 270 return (error); 271 flags = WRITECLOSE; 272 if (mp->mnt_flag & MNT_FORCE) 273 flags |= FORCECLOSE; 274 error = vflush(mp, 0, flags, td); 275 if (error) 276 return (error); 277 278 /* 279 * Now the volume is clean. Mark it so while the 280 * device is still rw. 281 */ 282 error = markvoldirty(pmp, 0); 283 if (error) { 284 (void)markvoldirty(pmp, 1); 285 return (error); 286 } 287 288 /* Downgrade the device from rw to ro. */ 289 DROP_GIANT(); 290 g_topology_lock(); 291 error = g_access(pmp->pm_cp, 0, -1, 0); 292 g_topology_unlock(); 293 PICKUP_GIANT(); 294 if (error) { 295 (void)markvoldirty(pmp, 1); 296 return (error); 297 } 298 299 /* 300 * Backing out after an error was painful in the 301 * above. Now we are committed to succeeding. 302 */ 303 pmp->pm_fmod = 0; 304 pmp->pm_flags |= MSDOSFSMNT_RONLY; 305 MNT_ILOCK(mp); 306 mp->mnt_flag |= MNT_RDONLY; 307 MNT_IUNLOCK(mp); 308 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 309 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 310 /* 311 * If upgrade to read-write by non-root, then verify 312 * that user has necessary permissions on the device. 313 */ 314 devvp = pmp->pm_devvp; 315 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td); 316 error = VOP_ACCESS(devvp, VREAD | VWRITE, 317 td->td_ucred, td); 318 if (error) 319 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 320 if (error) { 321 VOP_UNLOCK(devvp, 0, td); 322 return (error); 323 } 324 VOP_UNLOCK(devvp, 0, td); 325 DROP_GIANT(); 326 g_topology_lock(); 327 error = g_access(pmp->pm_cp, 0, 1, 0); 328 g_topology_unlock(); 329 PICKUP_GIANT(); 330 if (error) 331 return (error); 332 333 pmp->pm_fmod = 1; 334 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 335 MNT_ILOCK(mp); 336 mp->mnt_flag &= ~MNT_RDONLY; 337 MNT_IUNLOCK(mp); 338 339 /* Now that the volume is modifiable, mark it dirty. */ 340 error = markvoldirty(pmp, 1); 341 if (error) 342 return (error); 343 } 344 } 345 /* 346 * Not an update, or updating the name: look up the name 347 * and verify that it refers to a sensible disk device. 348 */ 349 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 350 return (EINVAL); 351 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 352 error = namei(&ndp); 353 if (error) 354 return (error); 355 devvp = ndp.ni_vp; 356 NDFREE(&ndp, NDF_ONLY_PNBUF); 357 358 if (!vn_isdisk(devvp, &error)) { 359 vput(devvp); 360 return (error); 361 } 362 /* 363 * If mount by non-root, then verify that user has necessary 364 * permissions on the device. 365 */ 366 accessmode = VREAD; 367 if ((mp->mnt_flag & MNT_RDONLY) == 0) 368 accessmode |= VWRITE; 369 error = VOP_ACCESS(devvp, accessmode, td->td_ucred, td); 370 if (error) 371 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 372 if (error) { 373 vput(devvp); 374 return (error); 375 } 376 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 377 error = mountmsdosfs(devvp, mp, td); 378#ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 379 pmp = VFSTOMSDOSFS(mp); 380#endif 381 } else { 382 if (devvp != pmp->pm_devvp) 383 error = EINVAL; /* XXX needs translation */ 384 else 385 vput(devvp); 386 } 387 if (error) { 388 vrele(devvp); 389 return (error); 390 } 391 392 error = update_mp(mp, td); 393 if (error) { 394 if ((mp->mnt_flag & MNT_UPDATE) == 0) 395 msdosfs_unmount(mp, MNT_FORCE, td); 396 return error; 397 } 398 399 vfs_mountedfrom(mp, from); 400#ifdef MSDOSFS_DEBUG 401 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 402#endif 403 return (0); 404} 405 406static int 407mountmsdosfs(struct vnode *devvp, struct mount *mp, struct thread *td) 408{ 409 struct msdosfsmount *pmp; 410 struct buf *bp; 411 struct cdev *dev = devvp->v_rdev; 412 union bootsector *bsp; 413 struct byte_bpb33 *b33; 414 struct byte_bpb50 *b50; 415 struct byte_bpb710 *b710; 416 u_int8_t SecPerClust; 417 u_long clusters; 418 int ronly, error; 419 struct g_consumer *cp; 420 struct bufobj *bo; 421 422 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 423 /* XXX: use VOP_ACCESS to check FS perms */ 424 DROP_GIANT(); 425 g_topology_lock(); 426 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 427 g_topology_unlock(); 428 PICKUP_GIANT(); 429 VOP_UNLOCK(devvp, 0, td); 430 if (error) 431 return (error); 432 433 bo = &devvp->v_bufobj; 434 bp = NULL; /* This and pmp both used in error_exit. */ 435 pmp = NULL; 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 /* 466 * Initialize ownerships and permissions, since nothing else will 467 * initialize them if 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 * Experimental support for large MS-DOS filesystems. 476 * WARNING: This uses at least 32 bytes of kernel memory (which is not 477 * reclaimed until the FS is unmounted) for each file on disk to map 478 * between the 32-bit inode numbers used by VFS and the 64-bit 479 * pseudo-inode numbers used internally by msdosfs. This is only 480 * safe to use in certain controlled situations (e.g. read-only FS 481 * with less than 1 million files). 482 * Since the mappings do not persist across unmounts (or reboots), these 483 * filesystems are not suitable for exporting through NFS, or any other 484 * application that requires fixed inode numbers. 485 */ 486 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS); 487 488 /* 489 * Compute several useful quantities from the bpb in the 490 * bootsector. Copy in the dos 5 variant of the bpb then fix up 491 * the fields that are different between dos 5 and dos 3.3. 492 */ 493 SecPerClust = b50->bpbSecPerClust; 494 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 495 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 496 error = EINVAL; 497 goto error_exit; 498 } 499 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 500 pmp->pm_FATs = b50->bpbFATs; 501 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 502 pmp->pm_Sectors = getushort(b50->bpbSectors); 503 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 504 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 505 pmp->pm_Heads = getushort(b50->bpbHeads); 506 pmp->pm_Media = b50->bpbMedia; 507 508 /* calculate the ratio of sector size to DEV_BSIZE */ 509 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 510 511 /* XXX - We should probably check more values here */ 512 if (!pmp->pm_BytesPerSec || !SecPerClust 513 || !pmp->pm_Heads 514#ifdef PC98 515 || !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 255) { 516#else 517 || !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) { 518#endif 519 error = EINVAL; 520 goto error_exit; 521 } 522 523 if (pmp->pm_Sectors == 0) { 524 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 525 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 526 } else { 527 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 528 pmp->pm_HugeSectors = pmp->pm_Sectors; 529 } 530 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) { 531 if (pmp->pm_HugeSectors > 0xffffffff / 532 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) { 533 /* 534 * We cannot deal currently with this size of disk 535 * due to fileid limitations (see msdosfs_getattr and 536 * msdosfs_readdir) 537 */ 538 error = EINVAL; 539 vfs_mount_error(mp, 540 "Disk too big, try '-o large' mount option"); 541 goto error_exit; 542 } 543 } 544 545 if (pmp->pm_RootDirEnts == 0) { 546 if (pmp->pm_Sectors 547 || pmp->pm_FATsecs 548 || getushort(b710->bpbFSVers)) { 549 error = EINVAL; 550 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 551 goto error_exit; 552 } 553 pmp->pm_fatmask = FAT32_MASK; 554 pmp->pm_fatmult = 4; 555 pmp->pm_fatdiv = 1; 556 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 557 if (getushort(b710->bpbExtFlags) & FATMIRROR) 558 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 559 else 560 pmp->pm_flags |= MSDOSFS_FATMIRROR; 561 } else 562 pmp->pm_flags |= MSDOSFS_FATMIRROR; 563 564 /* 565 * Check a few values (could do some more): 566 * - logical sector size: power of 2, >= block size 567 * - sectors per cluster: power of 2, >= 1 568 * - number of sectors: >= 1, <= size of partition 569 * - number of FAT sectors: >= 1 570 */ 571 if ( (SecPerClust == 0) 572 || (SecPerClust & (SecPerClust - 1)) 573 || (pmp->pm_BytesPerSec < DEV_BSIZE) 574 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 575 || (pmp->pm_HugeSectors == 0) 576 || (pmp->pm_FATsecs == 0) 577 ) { 578 error = EINVAL; 579 goto error_exit; 580 } 581 582 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 583 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 584 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 585 SecPerClust *= pmp->pm_BlkPerSec; 586 587 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 588 589 if (FAT32(pmp)) { 590 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 591 pmp->pm_firstcluster = pmp->pm_fatblk 592 + (pmp->pm_FATs * pmp->pm_FATsecs); 593 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 594 } else { 595 pmp->pm_rootdirblk = pmp->pm_fatblk + 596 (pmp->pm_FATs * pmp->pm_FATsecs); 597 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 598 + DEV_BSIZE - 1) 599 / DEV_BSIZE; /* in blocks */ 600 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 601 } 602 603 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 604 SecPerClust + 1; 605 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 606 607 if (pmp->pm_fatmask == 0) { 608 if (pmp->pm_maxcluster 609 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 610 /* 611 * This will usually be a floppy disk. This size makes 612 * sure that one fat entry will not be split across 613 * multiple blocks. 614 */ 615 pmp->pm_fatmask = FAT12_MASK; 616 pmp->pm_fatmult = 3; 617 pmp->pm_fatdiv = 2; 618 } else { 619 pmp->pm_fatmask = FAT16_MASK; 620 pmp->pm_fatmult = 2; 621 pmp->pm_fatdiv = 1; 622 } 623 } 624 625 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 626 if (pmp->pm_maxcluster >= clusters) { 627 printf("Warning: number of clusters (%ld) exceeds FAT " 628 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 629 pmp->pm_maxcluster = clusters - 1; 630 } 631 632 if (FAT12(pmp)) 633 pmp->pm_fatblocksize = 3 * 512; 634 else 635 pmp->pm_fatblocksize = PAGE_SIZE; 636 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 637 pmp->pm_BytesPerSec); 638 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 639 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 640 641 /* 642 * Compute mask and shift value for isolating cluster relative byte 643 * offsets and cluster numbers from a file offset. 644 */ 645 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 646 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 647 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 648 649 /* 650 * Check for valid cluster size 651 * must be a power of 2 652 */ 653 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 654 error = EINVAL; 655 goto error_exit; 656 } 657 658 /* 659 * Release the bootsector buffer. 660 */ 661 brelse(bp); 662 bp = NULL; 663 664 /* 665 * Check the fsinfo sector if we have one. Silently fix up our 666 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 667 * or too large. Ignore fp->fsinfree for now, since we need to 668 * read the entire FAT anyway to fill the inuse map. 669 */ 670 if (pmp->pm_fsinfo) { 671 struct fsinfo *fp; 672 673 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 674 NOCRED, &bp)) != 0) 675 goto error_exit; 676 fp = (struct fsinfo *)bp->b_data; 677 if (!bcmp(fp->fsisig1, "RRaA", 4) 678 && !bcmp(fp->fsisig2, "rrAa", 4) 679 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 680 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 681 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 682 pmp->pm_nxtfree = CLUST_FIRST; 683 } else 684 pmp->pm_fsinfo = 0; 685 brelse(bp); 686 bp = NULL; 687 } 688 689 /* 690 * Finish initializing pmp->pm_nxtfree (just in case the first few 691 * sectors aren't properly reserved in the FAT). This completes 692 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 693 * value if there is no fsinfo. We will use pmp->pm_nxtfree 694 * internally even if there is no fsinfo. 695 */ 696 if (pmp->pm_nxtfree < CLUST_FIRST) 697 pmp->pm_nxtfree = CLUST_FIRST; 698 699 /* 700 * Allocate memory for the bitmap of allocated clusters, and then 701 * fill it in. 702 */ 703 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 704 * sizeof(*pmp->pm_inusemap), 705 M_MSDOSFSFAT, M_WAITOK); 706 707 /* 708 * fillinusemap() needs pm_devvp. 709 */ 710 pmp->pm_devvp = devvp; 711 712 /* 713 * Have the inuse map filled in. 714 */ 715 if ((error = fillinusemap(pmp)) != 0) 716 goto error_exit; 717 718 /* 719 * If they want fat updates to be synchronous then let them suffer 720 * the performance degradation in exchange for the on disk copy of 721 * the fat being correct just about all the time. I suppose this 722 * would be a good thing to turn on if the kernel is still flakey. 723 */ 724 if (mp->mnt_flag & MNT_SYNCHRONOUS) 725 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 726 727 /* 728 * Finish up. 729 */ 730 if (ronly) 731 pmp->pm_flags |= MSDOSFSMNT_RONLY; 732 else { 733 if ((error = markvoldirty(pmp, 1)) != 0) { 734 (void)markvoldirty(pmp, 0); 735 goto error_exit; 736 } 737 pmp->pm_fmod = 1; 738 } 739 mp->mnt_data = pmp; 740 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 741 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 742 MNT_ILOCK(mp); 743 mp->mnt_flag |= MNT_LOCAL; 744 MNT_IUNLOCK(mp); 745 746 if (pmp->pm_flags & MSDOSFS_LARGEFS) 747 msdosfs_fileno_init(mp); 748 749 return 0; 750 751error_exit: 752 if (bp) 753 brelse(bp); 754 if (cp != NULL) { 755 DROP_GIANT(); 756 g_topology_lock(); 757 g_vfs_close(cp, td); 758 g_topology_unlock(); 759 PICKUP_GIANT(); 760 } 761 if (pmp) { 762 if (pmp->pm_inusemap) 763 free(pmp->pm_inusemap, M_MSDOSFSFAT); 764 free(pmp, M_MSDOSFSMNT); 765 mp->mnt_data = NULL; 766 } 767 return (error); 768} 769 770/* 771 * Unmount the filesystem described by mp. 772 */ 773static int 774msdosfs_unmount(struct mount *mp, int mntflags, struct thread *td) 775{ 776 struct msdosfsmount *pmp; 777 int error, flags; 778 779 flags = 0; 780 if (mntflags & MNT_FORCE) 781 flags |= FORCECLOSE; 782 error = vflush(mp, 0, flags, td); 783 if (error) 784 return error; 785 pmp = VFSTOMSDOSFS(mp); 786 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 787 error = markvoldirty(pmp, 0); 788 if (error) { 789 (void)markvoldirty(pmp, 1); 790 return (error); 791 } 792 } 793 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 794 if (pmp->pm_w2u) 795 msdosfs_iconv->close(pmp->pm_w2u); 796 if (pmp->pm_u2w) 797 msdosfs_iconv->close(pmp->pm_u2w); 798 if (pmp->pm_d2u) 799 msdosfs_iconv->close(pmp->pm_d2u); 800 if (pmp->pm_u2d) 801 msdosfs_iconv->close(pmp->pm_u2d); 802 } 803 804#ifdef MSDOSFS_DEBUG 805 { 806 struct vnode *vp = pmp->pm_devvp; 807 808 VI_LOCK(vp); 809 vn_printf(vp, 810 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 811 printf("freef %p, freeb %p, mount %p\n", 812 TAILQ_NEXT(vp, v_freelist), vp->v_freelist.tqe_prev, 813 vp->v_mount); 814 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 815 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 816 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 817 vp->v_bufobj.bo_numoutput, vp->v_type); 818 VI_UNLOCK(vp); 819 } 820#endif 821 DROP_GIANT(); 822 g_topology_lock(); 823 g_vfs_close(pmp->pm_cp, td); 824 g_topology_unlock(); 825 PICKUP_GIANT(); 826 vrele(pmp->pm_devvp); 827 free(pmp->pm_inusemap, M_MSDOSFSFAT); 828 if (pmp->pm_flags & MSDOSFS_LARGEFS) 829 msdosfs_fileno_free(mp); 830 free(pmp, M_MSDOSFSMNT); 831 mp->mnt_data = NULL; 832 MNT_ILOCK(mp); 833 mp->mnt_flag &= ~MNT_LOCAL; 834 MNT_IUNLOCK(mp); 835 return (0); 836} 837 838static int 839msdosfs_root(struct mount *mp, int flags, struct vnode **vpp, struct thread *td) 840{ 841 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 842 struct denode *ndep; 843 int error; 844 845#ifdef MSDOSFS_DEBUG 846 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 847#endif 848 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 849 if (error) 850 return (error); 851 *vpp = DETOV(ndep); 852 return (0); 853} 854 855static int 856msdosfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 857{ 858 struct msdosfsmount *pmp; 859 860 pmp = VFSTOMSDOSFS(mp); 861 sbp->f_bsize = pmp->pm_bpcluster; 862 sbp->f_iosize = pmp->pm_bpcluster; 863 sbp->f_blocks = pmp->pm_maxcluster + 1; 864 sbp->f_bfree = pmp->pm_freeclustercount; 865 sbp->f_bavail = pmp->pm_freeclustercount; 866 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 867 sbp->f_ffree = 0; /* what to put in here? */ 868 return (0); 869} 870 871static int 872msdosfs_sync(struct mount *mp, int waitfor, struct thread *td) 873{ 874 struct vnode *vp, *nvp; 875 struct denode *dep; 876 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 877 int error, allerror = 0; 878 879 /* 880 * If we ever switch to not updating all of the fats all the time, 881 * this would be the place to update them from the first one. 882 */ 883 if (pmp->pm_fmod != 0) { 884 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 885 panic("msdosfs_sync: rofs mod"); 886 else { 887 /* update fats here */ 888 } 889 } 890 /* 891 * Write back each (modified) denode. 892 */ 893 MNT_ILOCK(mp); 894loop: 895 MNT_VNODE_FOREACH(vp, mp, nvp) { 896 VI_LOCK(vp); 897 if (vp->v_type == VNON || (vp->v_iflag & VI_DOOMED)) { 898 VI_UNLOCK(vp); 899 continue; 900 } 901 MNT_IUNLOCK(mp); 902 dep = VTODE(vp); 903 if ((dep->de_flag & 904 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 905 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 906 waitfor == MNT_LAZY)) { 907 VI_UNLOCK(vp); 908 MNT_ILOCK(mp); 909 continue; 910 } 911 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 912 if (error) { 913 MNT_ILOCK(mp); 914 if (error == ENOENT) 915 goto loop; 916 continue; 917 } 918 error = VOP_FSYNC(vp, waitfor, td); 919 if (error) 920 allerror = error; 921 VOP_UNLOCK(vp, 0, td); 922 vrele(vp); 923 MNT_ILOCK(mp); 924 } 925 MNT_IUNLOCK(mp); 926 927 /* 928 * Flush filesystem control info. 929 */ 930 if (waitfor != MNT_LAZY) { 931 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY, td); 932 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 933 if (error) 934 allerror = error; 935 VOP_UNLOCK(pmp->pm_devvp, 0, td); 936 } 937 return (allerror); 938} 939 940static int 941msdosfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp) 942{ 943 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 944 struct defid *defhp = (struct defid *) fhp; 945 struct denode *dep; 946 int error; 947 948 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 949 if (error) { 950 *vpp = NULLVP; 951 return (error); 952 } 953 *vpp = DETOV(dep); 954 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 955 return (0); 956} 957 958static struct vfsops msdosfs_vfsops = { 959 .vfs_fhtovp = msdosfs_fhtovp, 960 .vfs_mount = msdosfs_mount, 961 .vfs_cmount = msdosfs_cmount, 962 .vfs_root = msdosfs_root, 963 .vfs_statfs = msdosfs_statfs, 964 .vfs_sync = msdosfs_sync, 965 .vfs_unmount = msdosfs_unmount, 966}; 967 968VFS_SET(msdosfs_vfsops, msdosfs, 0); 969MODULE_VERSION(msdosfs, 1); 970