msdosfs_vfsops.c revision 234466
1/* $FreeBSD: stable/9/sys/fs/msdosfs/msdosfs_vfsops.c 234466 2012-04-19 18:03:24Z mckusick $ */ 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/fcntl.h> 56#include <sys/iconv.h> 57#include <sys/kernel.h> 58#include <sys/lock.h> 59#include <sys/malloc.h> 60#include <sys/mount.h> 61#include <sys/mutex.h> 62#include <sys/namei.h> 63#include <sys/priv.h> 64#include <sys/proc.h> 65#include <sys/stat.h> 66#include <sys/vnode.h> 67 68#include <geom/geom.h> 69#include <geom/geom_vfs.h> 70 71#include <fs/msdosfs/bootsect.h> 72#include <fs/msdosfs/bpb.h> 73#include <fs/msdosfs/direntry.h> 74#include <fs/msdosfs/denode.h> 75#include <fs/msdosfs/fat.h> 76#include <fs/msdosfs/msdosfsmount.h> 77 78static const char msdosfs_lock_msg[] = "fatlk"; 79 80/* Mount options that we support. */ 81static const char *msdosfs_opts[] = { 82 "async", "noatime", "noclusterr", "noclusterw", 83 "export", "force", "from", "sync", 84 "cs_dos", "cs_local", "cs_win", "dirmask", 85 "gid", "kiconv", "large", "longname", 86 "longnames", "mask", "shortname", "shortnames", 87 "uid", "win95", "nowin95", 88 NULL 89}; 90 91#if 1 /*def PC98*/ 92/* 93 * XXX - The boot signature formatted by NEC PC-98 DOS looks like a 94 * garbage or a random value :-{ 95 * If you want to use that broken-signatured media, define the 96 * following symbol even though PC/AT. 97 * (ex. mount PC-98 DOS formatted FD on PC/AT) 98 */ 99#define MSDOSFS_NOCHECKSIG 100#endif 101 102MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); 103static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); 104 105struct iconv_functions *msdosfs_iconv; 106 107static int update_mp(struct mount *mp, struct thread *td); 108static int mountmsdosfs(struct vnode *devvp, struct mount *mp); 109static vfs_fhtovp_t msdosfs_fhtovp; 110static vfs_mount_t msdosfs_mount; 111static vfs_root_t msdosfs_root; 112static vfs_statfs_t msdosfs_statfs; 113static vfs_sync_t msdosfs_sync; 114static vfs_unmount_t msdosfs_unmount; 115 116/* Maximum length of a character set name (arbitrary). */ 117#define MAXCSLEN 64 118 119static int 120update_mp(struct mount *mp, struct thread *td) 121{ 122 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 123 void *dos, *win, *local; 124 int error, v; 125 126 if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { 127 if (msdosfs_iconv != NULL) { 128 error = vfs_getopt(mp->mnt_optnew, 129 "cs_win", &win, NULL); 130 if (!error) 131 error = vfs_getopt(mp->mnt_optnew, 132 "cs_local", &local, NULL); 133 if (!error) 134 error = vfs_getopt(mp->mnt_optnew, 135 "cs_dos", &dos, NULL); 136 if (!error) { 137 msdosfs_iconv->open(win, local, &pmp->pm_u2w); 138 msdosfs_iconv->open(local, win, &pmp->pm_w2u); 139 msdosfs_iconv->open(dos, local, &pmp->pm_u2d); 140 msdosfs_iconv->open(local, dos, &pmp->pm_d2u); 141 } 142 if (error != 0) 143 return (error); 144 } else { 145 pmp->pm_w2u = NULL; 146 pmp->pm_u2w = NULL; 147 pmp->pm_d2u = NULL; 148 pmp->pm_u2d = NULL; 149 } 150 } 151 152 if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1) 153 pmp->pm_gid = v; 154 if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1) 155 pmp->pm_uid = v; 156 if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1) 157 pmp->pm_mask = v & ALLPERMS; 158 if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1) 159 pmp->pm_dirmask = v & ALLPERMS; 160 vfs_flagopt(mp->mnt_optnew, "shortname", 161 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 162 vfs_flagopt(mp->mnt_optnew, "shortnames", 163 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 164 vfs_flagopt(mp->mnt_optnew, "longname", 165 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 166 vfs_flagopt(mp->mnt_optnew, "longnames", 167 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 168 vfs_flagopt(mp->mnt_optnew, "kiconv", 169 &pmp->pm_flags, MSDOSFSMNT_KICONV); 170 171 if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) 172 pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 173 else 174 pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; 175 176 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 177 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 178 else if (!(pmp->pm_flags & 179 (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) { 180 struct vnode *rootvp; 181 182 /* 183 * Try to divine whether to support Win'95 long filenames 184 */ 185 if (FAT32(pmp)) 186 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 187 else { 188 if ((error = 189 msdosfs_root(mp, LK_EXCLUSIVE, &rootvp)) != 0) 190 return error; 191 pmp->pm_flags |= findwin95(VTODE(rootvp)) ? 192 MSDOSFSMNT_LONGNAME : MSDOSFSMNT_SHORTNAME; 193 vput(rootvp); 194 } 195 } 196 return 0; 197} 198 199static int 200msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags) 201{ 202 struct msdosfs_args args; 203 struct export_args exp; 204 int error; 205 206 if (data == NULL) 207 return (EINVAL); 208 error = copyin(data, &args, sizeof args); 209 if (error) 210 return (error); 211 vfs_oexport_conv(&args.export, &exp); 212 213 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 214 ma = mount_arg(ma, "export", &exp, sizeof(exp)); 215 ma = mount_argf(ma, "uid", "%d", args.uid); 216 ma = mount_argf(ma, "gid", "%d", args.gid); 217 ma = mount_argf(ma, "mask", "%d", args.mask); 218 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 219 220 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 221 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 222 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 223 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 224 225 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 226 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 227 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 228 229 error = kernel_mount(ma, flags); 230 231 return (error); 232} 233 234/* 235 * mp - path - addr in user space of mount point (ie /usr or whatever) 236 * data - addr in user space of mount params including the name of the block 237 * special file to treat as a filesystem. 238 */ 239static int 240msdosfs_mount(struct mount *mp) 241{ 242 struct vnode *devvp; /* vnode for blk device to mount */ 243 struct thread *td; 244 /* msdosfs specific mount control block */ 245 struct msdosfsmount *pmp = NULL; 246 struct nameidata ndp; 247 int error, flags; 248 accmode_t accmode; 249 char *from; 250 251 td = curthread; 252 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 253 return (EINVAL); 254 255 /* 256 * If updating, check whether changing from read-only to 257 * read/write; if there is no device name, that's all we do. 258 */ 259 if (mp->mnt_flag & MNT_UPDATE) { 260 pmp = VFSTOMSDOSFS(mp); 261 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) { 262 /* 263 * Forbid export requests if filesystem has 264 * MSDOSFS_LARGEFS flag set. 265 */ 266 if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) { 267 vfs_mount_error(mp, 268 "MSDOSFS_LARGEFS flag set, cannot export"); 269 return (EOPNOTSUPP); 270 } 271 } 272 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 273 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 274 error = VFS_SYNC(mp, MNT_WAIT); 275 if (error) 276 return (error); 277 flags = WRITECLOSE; 278 if (mp->mnt_flag & MNT_FORCE) 279 flags |= FORCECLOSE; 280 error = vflush(mp, 0, flags, td); 281 if (error) 282 return (error); 283 284 /* 285 * Now the volume is clean. Mark it so while the 286 * device is still rw. 287 */ 288 error = markvoldirty(pmp, 0); 289 if (error) { 290 (void)markvoldirty(pmp, 1); 291 return (error); 292 } 293 294 /* Downgrade the device from rw to ro. */ 295 DROP_GIANT(); 296 g_topology_lock(); 297 error = g_access(pmp->pm_cp, 0, -1, 0); 298 g_topology_unlock(); 299 PICKUP_GIANT(); 300 if (error) { 301 (void)markvoldirty(pmp, 1); 302 return (error); 303 } 304 305 /* 306 * Backing out after an error was painful in the 307 * above. Now we are committed to succeeding. 308 */ 309 pmp->pm_fmod = 0; 310 pmp->pm_flags |= MSDOSFSMNT_RONLY; 311 MNT_ILOCK(mp); 312 mp->mnt_flag |= MNT_RDONLY; 313 MNT_IUNLOCK(mp); 314 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 315 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 316 /* 317 * If upgrade to read-write by non-root, then verify 318 * that user has necessary permissions on the device. 319 */ 320 devvp = pmp->pm_devvp; 321 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 322 error = VOP_ACCESS(devvp, VREAD | VWRITE, 323 td->td_ucred, td); 324 if (error) 325 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 326 if (error) { 327 VOP_UNLOCK(devvp, 0); 328 return (error); 329 } 330 VOP_UNLOCK(devvp, 0); 331 DROP_GIANT(); 332 g_topology_lock(); 333 error = g_access(pmp->pm_cp, 0, 1, 0); 334 g_topology_unlock(); 335 PICKUP_GIANT(); 336 if (error) 337 return (error); 338 339 pmp->pm_fmod = 1; 340 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 341 MNT_ILOCK(mp); 342 mp->mnt_flag &= ~MNT_RDONLY; 343 MNT_IUNLOCK(mp); 344 345 /* Now that the volume is modifiable, mark it dirty. */ 346 error = markvoldirty(pmp, 1); 347 if (error) 348 return (error); 349 } 350 } 351 /* 352 * Not an update, or updating the name: look up the name 353 * and verify that it refers to a sensible disk device. 354 */ 355 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 356 return (EINVAL); 357 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 358 error = namei(&ndp); 359 if (error) 360 return (error); 361 devvp = ndp.ni_vp; 362 NDFREE(&ndp, NDF_ONLY_PNBUF); 363 364 if (!vn_isdisk(devvp, &error)) { 365 vput(devvp); 366 return (error); 367 } 368 /* 369 * If mount by non-root, then verify that user has necessary 370 * permissions on the device. 371 */ 372 accmode = VREAD; 373 if ((mp->mnt_flag & MNT_RDONLY) == 0) 374 accmode |= VWRITE; 375 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 376 if (error) 377 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 378 if (error) { 379 vput(devvp); 380 return (error); 381 } 382 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 383 error = mountmsdosfs(devvp, mp); 384#ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 385 pmp = VFSTOMSDOSFS(mp); 386#endif 387 } else { 388 vput(devvp); 389 if (devvp != pmp->pm_devvp) 390 return (EINVAL); /* XXX needs translation */ 391 } 392 if (error) { 393 vrele(devvp); 394 return (error); 395 } 396 397 error = update_mp(mp, td); 398 if (error) { 399 if ((mp->mnt_flag & MNT_UPDATE) == 0) 400 msdosfs_unmount(mp, MNT_FORCE); 401 return error; 402 } 403 404 if (devvp->v_type == VCHR && devvp->v_rdev != NULL) 405 devvp->v_rdev->si_mountpt = mp; 406 vfs_mountedfrom(mp, from); 407#ifdef MSDOSFS_DEBUG 408 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 409#endif 410 return (0); 411} 412 413static int 414mountmsdosfs(struct vnode *devvp, struct mount *mp) 415{ 416 struct msdosfsmount *pmp; 417 struct buf *bp; 418 struct cdev *dev; 419 union bootsector *bsp; 420 struct byte_bpb33 *b33; 421 struct byte_bpb50 *b50; 422 struct byte_bpb710 *b710; 423 u_int8_t SecPerClust; 424 u_long clusters; 425 int ronly, error; 426 struct g_consumer *cp; 427 struct bufobj *bo; 428 429 bp = NULL; /* This and pmp both used in error_exit. */ 430 pmp = NULL; 431 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 432 433 dev = devvp->v_rdev; 434 dev_ref(dev); 435 DROP_GIANT(); 436 g_topology_lock(); 437 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 438 g_topology_unlock(); 439 PICKUP_GIANT(); 440 VOP_UNLOCK(devvp, 0); 441 if (error) 442 goto error_exit; 443 444 bo = &devvp->v_bufobj; 445 446 /* 447 * Read the boot sector of the filesystem, and then check the 448 * boot signature. If not a dos boot sector then error out. 449 * 450 * NOTE: 8192 is a magic size that works for ffs. 451 */ 452 error = bread(devvp, 0, 8192, NOCRED, &bp); 453 if (error) 454 goto error_exit; 455 bp->b_flags |= B_AGE; 456 bsp = (union bootsector *)bp->b_data; 457 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 458 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 459 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 460 461#ifndef MSDOSFS_NOCHECKSIG 462 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 463 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 464 error = EINVAL; 465 goto error_exit; 466 } 467#endif 468 469 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 470 pmp->pm_mountp = mp; 471 pmp->pm_cp = cp; 472 pmp->pm_bo = bo; 473 474 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); 475 476 /* 477 * Initialize ownerships and permissions, since nothing else will 478 * initialize them iff we are mounting root. 479 */ 480 pmp->pm_uid = UID_ROOT; 481 pmp->pm_gid = GID_WHEEL; 482 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 483 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 484 485 /* 486 * Experimental support for large MS-DOS filesystems. 487 * WARNING: This uses at least 32 bytes of kernel memory (which is not 488 * reclaimed until the FS is unmounted) for each file on disk to map 489 * between the 32-bit inode numbers used by VFS and the 64-bit 490 * pseudo-inode numbers used internally by msdosfs. This is only 491 * safe to use in certain controlled situations (e.g. read-only FS 492 * with less than 1 million files). 493 * Since the mappings do not persist across unmounts (or reboots), these 494 * filesystems are not suitable for exporting through NFS, or any other 495 * application that requires fixed inode numbers. 496 */ 497 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS); 498 499 /* 500 * Compute several useful quantities from the bpb in the 501 * bootsector. Copy in the dos 5 variant of the bpb then fix up 502 * the fields that are different between dos 5 and dos 3.3. 503 */ 504 SecPerClust = b50->bpbSecPerClust; 505 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 506 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 507 error = EINVAL; 508 goto error_exit; 509 } 510 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 511 pmp->pm_FATs = b50->bpbFATs; 512 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 513 pmp->pm_Sectors = getushort(b50->bpbSectors); 514 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 515 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 516 pmp->pm_Heads = getushort(b50->bpbHeads); 517 pmp->pm_Media = b50->bpbMedia; 518 519 /* calculate the ratio of sector size to DEV_BSIZE */ 520 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 521 522 /* 523 * We don't check pm_Heads nor pm_SecPerTrack, because 524 * these may not be set for EFI file systems. We don't 525 * use these anyway, so we're unaffected if they are 526 * invalid. 527 */ 528 if (!pmp->pm_BytesPerSec || !SecPerClust) { 529 error = EINVAL; 530 goto error_exit; 531 } 532 533 if (pmp->pm_Sectors == 0) { 534 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 535 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 536 } else { 537 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 538 pmp->pm_HugeSectors = pmp->pm_Sectors; 539 } 540 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) { 541 if (pmp->pm_HugeSectors > 0xffffffff / 542 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) { 543 /* 544 * We cannot deal currently with this size of disk 545 * due to fileid limitations (see msdosfs_getattr and 546 * msdosfs_readdir) 547 */ 548 error = EINVAL; 549 vfs_mount_error(mp, 550 "Disk too big, try '-o large' mount option"); 551 goto error_exit; 552 } 553 } 554 555 if (pmp->pm_RootDirEnts == 0) { 556 if (pmp->pm_Sectors 557 || pmp->pm_FATsecs 558 || getushort(b710->bpbFSVers)) { 559 error = EINVAL; 560#ifdef MSDOSFS_DEBUG 561 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 562#endif 563 goto error_exit; 564 } 565 pmp->pm_fatmask = FAT32_MASK; 566 pmp->pm_fatmult = 4; 567 pmp->pm_fatdiv = 1; 568 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 569 if (getushort(b710->bpbExtFlags) & FATMIRROR) 570 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 571 else 572 pmp->pm_flags |= MSDOSFS_FATMIRROR; 573 } else 574 pmp->pm_flags |= MSDOSFS_FATMIRROR; 575 576 /* 577 * Check a few values (could do some more): 578 * - logical sector size: power of 2, >= block size 579 * - sectors per cluster: power of 2, >= 1 580 * - number of sectors: >= 1, <= size of partition 581 * - number of FAT sectors: >= 1 582 */ 583 if ( (SecPerClust == 0) 584 || (SecPerClust & (SecPerClust - 1)) 585 || (pmp->pm_BytesPerSec < DEV_BSIZE) 586 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 587 || (pmp->pm_HugeSectors == 0) 588 || (pmp->pm_FATsecs == 0) 589 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) 590 ) { 591 error = EINVAL; 592 goto error_exit; 593 } 594 595 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 596 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 597 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 598 SecPerClust *= pmp->pm_BlkPerSec; 599 600 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 601 602 if (FAT32(pmp)) { 603 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 604 pmp->pm_firstcluster = pmp->pm_fatblk 605 + (pmp->pm_FATs * pmp->pm_FATsecs); 606 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 607 } else { 608 pmp->pm_rootdirblk = pmp->pm_fatblk + 609 (pmp->pm_FATs * pmp->pm_FATsecs); 610 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 611 + DEV_BSIZE - 1) 612 / DEV_BSIZE; /* in blocks */ 613 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 614 } 615 616 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 617 SecPerClust + 1; 618 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 619 620 if (pmp->pm_fatmask == 0) { 621 if (pmp->pm_maxcluster 622 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 623 /* 624 * This will usually be a floppy disk. This size makes 625 * sure that one fat entry will not be split across 626 * multiple blocks. 627 */ 628 pmp->pm_fatmask = FAT12_MASK; 629 pmp->pm_fatmult = 3; 630 pmp->pm_fatdiv = 2; 631 } else { 632 pmp->pm_fatmask = FAT16_MASK; 633 pmp->pm_fatmult = 2; 634 pmp->pm_fatdiv = 1; 635 } 636 } 637 638 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 639 if (pmp->pm_maxcluster >= clusters) { 640#ifdef MSDOSFS_DEBUG 641 printf("Warning: number of clusters (%ld) exceeds FAT " 642 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 643#endif 644 pmp->pm_maxcluster = clusters - 1; 645 } 646 647 if (FAT12(pmp)) 648 pmp->pm_fatblocksize = 3 * 512; 649 else 650 pmp->pm_fatblocksize = PAGE_SIZE; 651 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 652 pmp->pm_BytesPerSec); 653 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 654 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 655 656 /* 657 * Compute mask and shift value for isolating cluster relative byte 658 * offsets and cluster numbers from a file offset. 659 */ 660 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 661 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 662 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 663 664 /* 665 * Check for valid cluster size 666 * must be a power of 2 667 */ 668 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 669 error = EINVAL; 670 goto error_exit; 671 } 672 673 /* 674 * Release the bootsector buffer. 675 */ 676 brelse(bp); 677 bp = NULL; 678 679 /* 680 * Check the fsinfo sector if we have one. Silently fix up our 681 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 682 * or too large. Ignore fp->fsinfree for now, since we need to 683 * read the entire FAT anyway to fill the inuse map. 684 */ 685 if (pmp->pm_fsinfo) { 686 struct fsinfo *fp; 687 688 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 689 NOCRED, &bp)) != 0) 690 goto error_exit; 691 fp = (struct fsinfo *)bp->b_data; 692 if (!bcmp(fp->fsisig1, "RRaA", 4) 693 && !bcmp(fp->fsisig2, "rrAa", 4) 694 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 695 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 696 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 697 pmp->pm_nxtfree = CLUST_FIRST; 698 } else 699 pmp->pm_fsinfo = 0; 700 brelse(bp); 701 bp = NULL; 702 } 703 704 /* 705 * Finish initializing pmp->pm_nxtfree (just in case the first few 706 * sectors aren't properly reserved in the FAT). This completes 707 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 708 * value if there is no fsinfo. We will use pmp->pm_nxtfree 709 * internally even if there is no fsinfo. 710 */ 711 if (pmp->pm_nxtfree < CLUST_FIRST) 712 pmp->pm_nxtfree = CLUST_FIRST; 713 714 /* 715 * Allocate memory for the bitmap of allocated clusters, and then 716 * fill it in. 717 */ 718 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 719 * sizeof(*pmp->pm_inusemap), 720 M_MSDOSFSFAT, M_WAITOK); 721 722 /* 723 * fillinusemap() needs pm_devvp. 724 */ 725 pmp->pm_devvp = devvp; 726 pmp->pm_dev = dev; 727 728 /* 729 * Have the inuse map filled in. 730 */ 731 MSDOSFS_LOCK_MP(pmp); 732 error = fillinusemap(pmp); 733 MSDOSFS_UNLOCK_MP(pmp); 734 if (error != 0) 735 goto error_exit; 736 737 /* 738 * If they want fat updates to be synchronous then let them suffer 739 * the performance degradation in exchange for the on disk copy of 740 * the fat being correct just about all the time. I suppose this 741 * would be a good thing to turn on if the kernel is still flakey. 742 */ 743 if (mp->mnt_flag & MNT_SYNCHRONOUS) 744 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 745 746 /* 747 * Finish up. 748 */ 749 if (ronly) 750 pmp->pm_flags |= MSDOSFSMNT_RONLY; 751 else { 752 if ((error = markvoldirty(pmp, 1)) != 0) { 753 (void)markvoldirty(pmp, 0); 754 goto error_exit; 755 } 756 pmp->pm_fmod = 1; 757 } 758 mp->mnt_data = pmp; 759 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 760 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 761 MNT_ILOCK(mp); 762 mp->mnt_flag |= MNT_LOCAL; 763 mp->mnt_kern_flag |= MNTK_MPSAFE; 764 MNT_IUNLOCK(mp); 765 766 if (pmp->pm_flags & MSDOSFS_LARGEFS) 767 msdosfs_fileno_init(mp); 768 769 return 0; 770 771error_exit: 772 if (bp) 773 brelse(bp); 774 if (cp != NULL) { 775 DROP_GIANT(); 776 g_topology_lock(); 777 g_vfs_close(cp); 778 g_topology_unlock(); 779 PICKUP_GIANT(); 780 } 781 if (pmp) { 782 lockdestroy(&pmp->pm_fatlock); 783 if (pmp->pm_inusemap) 784 free(pmp->pm_inusemap, M_MSDOSFSFAT); 785 free(pmp, M_MSDOSFSMNT); 786 mp->mnt_data = NULL; 787 } 788 dev_rel(dev); 789 return (error); 790} 791 792/* 793 * Unmount the filesystem described by mp. 794 */ 795static int 796msdosfs_unmount(struct mount *mp, int mntflags) 797{ 798 struct msdosfsmount *pmp; 799 int error, flags; 800 801 flags = 0; 802 if (mntflags & MNT_FORCE) 803 flags |= FORCECLOSE; 804 error = vflush(mp, 0, flags, curthread); 805 if (error && error != ENXIO) 806 return error; 807 pmp = VFSTOMSDOSFS(mp); 808 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 809 error = markvoldirty(pmp, 0); 810 if (error && error != ENXIO) { 811 (void)markvoldirty(pmp, 1); 812 return (error); 813 } 814 } 815 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 816 if (pmp->pm_w2u) 817 msdosfs_iconv->close(pmp->pm_w2u); 818 if (pmp->pm_u2w) 819 msdosfs_iconv->close(pmp->pm_u2w); 820 if (pmp->pm_d2u) 821 msdosfs_iconv->close(pmp->pm_d2u); 822 if (pmp->pm_u2d) 823 msdosfs_iconv->close(pmp->pm_u2d); 824 } 825 826#ifdef MSDOSFS_DEBUG 827 { 828 struct vnode *vp = pmp->pm_devvp; 829 struct bufobj *bo; 830 831 bo = &vp->v_bufobj; 832 BO_LOCK(bo); 833 VI_LOCK(vp); 834 vn_printf(vp, 835 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 836 printf("freef %p, freeb %p, mount %p\n", 837 TAILQ_NEXT(vp, v_freelist), vp->v_freelist.tqe_prev, 838 vp->v_mount); 839 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 840 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 841 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 842 vp->v_bufobj.bo_numoutput, vp->v_type); 843 VI_UNLOCK(vp); 844 BO_UNLOCK(bo); 845 } 846#endif 847 DROP_GIANT(); 848 if (pmp->pm_devvp->v_type == VCHR && pmp->pm_devvp->v_rdev != NULL) 849 pmp->pm_devvp->v_rdev->si_mountpt = NULL; 850 g_topology_lock(); 851 g_vfs_close(pmp->pm_cp); 852 g_topology_unlock(); 853 PICKUP_GIANT(); 854 vrele(pmp->pm_devvp); 855 dev_rel(pmp->pm_dev); 856 free(pmp->pm_inusemap, M_MSDOSFSFAT); 857 if (pmp->pm_flags & MSDOSFS_LARGEFS) 858 msdosfs_fileno_free(mp); 859 lockdestroy(&pmp->pm_fatlock); 860 free(pmp, M_MSDOSFSMNT); 861 mp->mnt_data = NULL; 862 MNT_ILOCK(mp); 863 mp->mnt_flag &= ~MNT_LOCAL; 864 MNT_IUNLOCK(mp); 865 return (error); 866} 867 868static int 869msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 870{ 871 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 872 struct denode *ndep; 873 int error; 874 875#ifdef MSDOSFS_DEBUG 876 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 877#endif 878 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 879 if (error) 880 return (error); 881 *vpp = DETOV(ndep); 882 return (0); 883} 884 885static int 886msdosfs_statfs(struct mount *mp, struct statfs *sbp) 887{ 888 struct msdosfsmount *pmp; 889 890 pmp = VFSTOMSDOSFS(mp); 891 sbp->f_bsize = pmp->pm_bpcluster; 892 sbp->f_iosize = pmp->pm_bpcluster; 893 sbp->f_blocks = pmp->pm_maxcluster + 1; 894 sbp->f_bfree = pmp->pm_freeclustercount; 895 sbp->f_bavail = pmp->pm_freeclustercount; 896 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 897 sbp->f_ffree = 0; /* what to put in here? */ 898 return (0); 899} 900 901static int 902msdosfs_sync(struct mount *mp, int waitfor) 903{ 904 struct vnode *vp, *nvp; 905 struct thread *td; 906 struct denode *dep; 907 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 908 int error, allerror = 0; 909 910 td = curthread; 911 912 /* 913 * If we ever switch to not updating all of the fats all the time, 914 * this would be the place to update them from the first one. 915 */ 916 if (pmp->pm_fmod != 0) { 917 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 918 panic("msdosfs_sync: rofs mod"); 919 else { 920 /* update fats here */ 921 } 922 } 923 /* 924 * Write back each (modified) denode. 925 */ 926 MNT_ILOCK(mp); 927loop: 928 MNT_VNODE_FOREACH(vp, mp, nvp) { 929 VI_LOCK(vp); 930 if (vp->v_type == VNON || (vp->v_iflag & VI_DOOMED)) { 931 VI_UNLOCK(vp); 932 continue; 933 } 934 MNT_IUNLOCK(mp); 935 dep = VTODE(vp); 936 if ((dep->de_flag & 937 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 938 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 939 waitfor == MNT_LAZY)) { 940 VI_UNLOCK(vp); 941 MNT_ILOCK(mp); 942 continue; 943 } 944 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 945 if (error) { 946 MNT_ILOCK(mp); 947 if (error == ENOENT) 948 goto loop; 949 continue; 950 } 951 error = VOP_FSYNC(vp, waitfor, td); 952 if (error) 953 allerror = error; 954 VOP_UNLOCK(vp, 0); 955 vrele(vp); 956 MNT_ILOCK(mp); 957 } 958 MNT_IUNLOCK(mp); 959 960 /* 961 * Flush filesystem control info. 962 */ 963 if (waitfor != MNT_LAZY) { 964 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 965 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 966 if (error) 967 allerror = error; 968 VOP_UNLOCK(pmp->pm_devvp, 0); 969 } 970 return (allerror); 971} 972 973static int 974msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) 975{ 976 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 977 struct defid *defhp = (struct defid *) fhp; 978 struct denode *dep; 979 int error; 980 981 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 982 if (error) { 983 *vpp = NULLVP; 984 return (error); 985 } 986 *vpp = DETOV(dep); 987 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 988 return (0); 989} 990 991static struct vfsops msdosfs_vfsops = { 992 .vfs_fhtovp = msdosfs_fhtovp, 993 .vfs_mount = msdosfs_mount, 994 .vfs_cmount = msdosfs_cmount, 995 .vfs_root = msdosfs_root, 996 .vfs_statfs = msdosfs_statfs, 997 .vfs_sync = msdosfs_sync, 998 .vfs_unmount = msdosfs_unmount, 999}; 1000 1001VFS_SET(msdosfs_vfsops, msdosfs, 0); 1002MODULE_VERSION(msdosfs, 1); 1003