1/* $FreeBSD: stable/11/sys/fs/msdosfs/msdosfs_vfsops.c 308545 2016-11-11 19:40:34Z kib $ */ 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 179 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 180 return 0; 181} 182 183static int 184msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags) 185{ 186 struct msdosfs_args args; 187 struct export_args exp; 188 int error; 189 190 if (data == NULL) 191 return (EINVAL); 192 error = copyin(data, &args, sizeof args); 193 if (error) 194 return (error); 195 vfs_oexport_conv(&args.export, &exp); 196 197 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 198 ma = mount_arg(ma, "export", &exp, sizeof(exp)); 199 ma = mount_argf(ma, "uid", "%d", args.uid); 200 ma = mount_argf(ma, "gid", "%d", args.gid); 201 ma = mount_argf(ma, "mask", "%d", args.mask); 202 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 203 204 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 205 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 206 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 207 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 208 209 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 210 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 211 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 212 213 error = kernel_mount(ma, flags); 214 215 return (error); 216} 217 218/* 219 * mp - path - addr in user space of mount point (ie /usr or whatever) 220 * data - addr in user space of mount params including the name of the block 221 * special file to treat as a filesystem. 222 */ 223static int 224msdosfs_mount(struct mount *mp) 225{ 226 struct vnode *devvp; /* vnode for blk device to mount */ 227 struct thread *td; 228 /* msdosfs specific mount control block */ 229 struct msdosfsmount *pmp = NULL; 230 struct nameidata ndp; 231 int error, flags; 232 accmode_t accmode; 233 char *from; 234 235 td = curthread; 236 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 237 return (EINVAL); 238 239 /* 240 * If updating, check whether changing from read-only to 241 * read/write; if there is no device name, that's all we do. 242 */ 243 if (mp->mnt_flag & MNT_UPDATE) { 244 pmp = VFSTOMSDOSFS(mp); 245 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) { 246 /* 247 * Forbid export requests if filesystem has 248 * MSDOSFS_LARGEFS flag set. 249 */ 250 if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) { 251 vfs_mount_error(mp, 252 "MSDOSFS_LARGEFS flag set, cannot export"); 253 return (EOPNOTSUPP); 254 } 255 } 256 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 257 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 258 error = VFS_SYNC(mp, MNT_WAIT); 259 if (error) 260 return (error); 261 flags = WRITECLOSE; 262 if (mp->mnt_flag & MNT_FORCE) 263 flags |= FORCECLOSE; 264 error = vflush(mp, 0, flags, td); 265 if (error) 266 return (error); 267 268 /* 269 * Now the volume is clean. Mark it so while the 270 * device is still rw. 271 */ 272 error = markvoldirty(pmp, 0); 273 if (error) { 274 (void)markvoldirty(pmp, 1); 275 return (error); 276 } 277 278 /* Downgrade the device from rw to ro. */ 279 g_topology_lock(); 280 error = g_access(pmp->pm_cp, 0, -1, 0); 281 g_topology_unlock(); 282 if (error) { 283 (void)markvoldirty(pmp, 1); 284 return (error); 285 } 286 287 /* 288 * Backing out after an error was painful in the 289 * above. Now we are committed to succeeding. 290 */ 291 pmp->pm_fmod = 0; 292 pmp->pm_flags |= MSDOSFSMNT_RONLY; 293 MNT_ILOCK(mp); 294 mp->mnt_flag |= MNT_RDONLY; 295 MNT_IUNLOCK(mp); 296 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 297 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 298 /* 299 * If upgrade to read-write by non-root, then verify 300 * that user has necessary permissions on the device. 301 */ 302 devvp = pmp->pm_devvp; 303 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 304 error = VOP_ACCESS(devvp, VREAD | VWRITE, 305 td->td_ucred, td); 306 if (error) 307 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 308 if (error) { 309 VOP_UNLOCK(devvp, 0); 310 return (error); 311 } 312 VOP_UNLOCK(devvp, 0); 313 g_topology_lock(); 314 error = g_access(pmp->pm_cp, 0, 1, 0); 315 g_topology_unlock(); 316 if (error) 317 return (error); 318 319 pmp->pm_fmod = 1; 320 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 321 MNT_ILOCK(mp); 322 mp->mnt_flag &= ~MNT_RDONLY; 323 MNT_IUNLOCK(mp); 324 325 /* Now that the volume is modifiable, mark it dirty. */ 326 error = markvoldirty(pmp, 1); 327 if (error) 328 return (error); 329 } 330 } 331 /* 332 * Not an update, or updating the name: look up the name 333 * and verify that it refers to a sensible disk device. 334 */ 335 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 336 return (EINVAL); 337 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 338 error = namei(&ndp); 339 if (error) 340 return (error); 341 devvp = ndp.ni_vp; 342 NDFREE(&ndp, NDF_ONLY_PNBUF); 343 344 if (!vn_isdisk(devvp, &error)) { 345 vput(devvp); 346 return (error); 347 } 348 /* 349 * If mount by non-root, then verify that user has necessary 350 * permissions on the device. 351 */ 352 accmode = VREAD; 353 if ((mp->mnt_flag & MNT_RDONLY) == 0) 354 accmode |= VWRITE; 355 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 356 if (error) 357 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 358 if (error) { 359 vput(devvp); 360 return (error); 361 } 362 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 363 error = mountmsdosfs(devvp, mp); 364#ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 365 pmp = VFSTOMSDOSFS(mp); 366#endif 367 } else { 368 vput(devvp); 369 if (devvp != pmp->pm_devvp) 370 return (EINVAL); /* XXX needs translation */ 371 } 372 if (error) { 373 vrele(devvp); 374 return (error); 375 } 376 377 error = update_mp(mp, td); 378 if (error) { 379 if ((mp->mnt_flag & MNT_UPDATE) == 0) 380 msdosfs_unmount(mp, MNT_FORCE); 381 return error; 382 } 383 384 vfs_mountedfrom(mp, from); 385#ifdef MSDOSFS_DEBUG 386 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 387#endif 388 return (0); 389} 390 391static int 392mountmsdosfs(struct vnode *devvp, struct mount *mp) 393{ 394 struct msdosfsmount *pmp; 395 struct buf *bp; 396 struct cdev *dev; 397 union bootsector *bsp; 398 struct byte_bpb33 *b33; 399 struct byte_bpb50 *b50; 400 struct byte_bpb710 *b710; 401 u_int8_t SecPerClust; 402 u_long clusters; 403 int ronly, error; 404 struct g_consumer *cp; 405 struct bufobj *bo; 406 407 bp = NULL; /* This and pmp both used in error_exit. */ 408 pmp = NULL; 409 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 410 411 dev = devvp->v_rdev; 412 if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0, 413 (uintptr_t)mp) == 0) { 414 VOP_UNLOCK(devvp, 0); 415 return (EBUSY); 416 } 417 g_topology_lock(); 418 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 419 g_topology_unlock(); 420 if (error != 0) { 421 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 422 VOP_UNLOCK(devvp, 0); 423 return (error); 424 } 425 dev_ref(dev); 426 VOP_UNLOCK(devvp, 0); 427 428 bo = &devvp->v_bufobj; 429 430 /* 431 * Read the boot sector of the filesystem, and then check the 432 * boot signature. If not a dos boot sector then error out. 433 * 434 * NOTE: 8192 is a magic size that works for ffs. 435 */ 436 error = bread(devvp, 0, 8192, NOCRED, &bp); 437 if (error) 438 goto error_exit; 439 bp->b_flags |= B_AGE; 440 bsp = (union bootsector *)bp->b_data; 441 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 442 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 443 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 444 445#ifndef MSDOSFS_NOCHECKSIG 446 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 447 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 448 error = EINVAL; 449 goto error_exit; 450 } 451#endif 452 453 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 454 pmp->pm_mountp = mp; 455 pmp->pm_cp = cp; 456 pmp->pm_bo = bo; 457 458 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); 459 460 /* 461 * Initialize ownerships and permissions, since nothing else will 462 * initialize them iff we are mounting root. 463 */ 464 pmp->pm_uid = UID_ROOT; 465 pmp->pm_gid = GID_WHEEL; 466 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 467 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 468 469 /* 470 * Experimental support for large MS-DOS filesystems. 471 * WARNING: This uses at least 32 bytes of kernel memory (which is not 472 * reclaimed until the FS is unmounted) for each file on disk to map 473 * between the 32-bit inode numbers used by VFS and the 64-bit 474 * pseudo-inode numbers used internally by msdosfs. This is only 475 * safe to use in certain controlled situations (e.g. read-only FS 476 * with less than 1 million files). 477 * Since the mappings do not persist across unmounts (or reboots), these 478 * filesystems are not suitable for exporting through NFS, or any other 479 * application that requires fixed inode numbers. 480 */ 481 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS); 482 483 /* 484 * Compute several useful quantities from the bpb in the 485 * bootsector. Copy in the dos 5 variant of the bpb then fix up 486 * the fields that are different between dos 5 and dos 3.3. 487 */ 488 SecPerClust = b50->bpbSecPerClust; 489 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 490 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 491 error = EINVAL; 492 goto error_exit; 493 } 494 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 495 pmp->pm_FATs = b50->bpbFATs; 496 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 497 pmp->pm_Sectors = getushort(b50->bpbSectors); 498 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 499 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 500 pmp->pm_Heads = getushort(b50->bpbHeads); 501 pmp->pm_Media = b50->bpbMedia; 502 503 /* calculate the ratio of sector size to DEV_BSIZE */ 504 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 505 506 /* 507 * We don't check pm_Heads nor pm_SecPerTrack, because 508 * these may not be set for EFI file systems. We don't 509 * use these anyway, so we're unaffected if they are 510 * invalid. 511 */ 512 if (!pmp->pm_BytesPerSec || !SecPerClust) { 513 error = EINVAL; 514 goto error_exit; 515 } 516 517 if (pmp->pm_Sectors == 0) { 518 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 519 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 520 } else { 521 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 522 pmp->pm_HugeSectors = pmp->pm_Sectors; 523 } 524 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) { 525 if (pmp->pm_HugeSectors > 0xffffffff / 526 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) { 527 /* 528 * We cannot deal currently with this size of disk 529 * due to fileid limitations (see msdosfs_getattr and 530 * msdosfs_readdir) 531 */ 532 error = EINVAL; 533 vfs_mount_error(mp, 534 "Disk too big, try '-o large' mount option"); 535 goto error_exit; 536 } 537 } 538 539 if (pmp->pm_RootDirEnts == 0) { 540 if (pmp->pm_FATsecs 541 || getushort(b710->bpbFSVers)) { 542 error = EINVAL; 543#ifdef MSDOSFS_DEBUG 544 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 545#endif 546 goto error_exit; 547 } 548 pmp->pm_fatmask = FAT32_MASK; 549 pmp->pm_fatmult = 4; 550 pmp->pm_fatdiv = 1; 551 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 552 if (getushort(b710->bpbExtFlags) & FATMIRROR) 553 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 554 else 555 pmp->pm_flags |= MSDOSFS_FATMIRROR; 556 } else 557 pmp->pm_flags |= MSDOSFS_FATMIRROR; 558 559 /* 560 * Check a few values (could do some more): 561 * - logical sector size: power of 2, >= block size 562 * - sectors per cluster: power of 2, >= 1 563 * - number of sectors: >= 1, <= size of partition 564 * - number of FAT sectors: >= 1 565 */ 566 if ( (SecPerClust == 0) 567 || (SecPerClust & (SecPerClust - 1)) 568 || (pmp->pm_BytesPerSec < DEV_BSIZE) 569 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 570 || (pmp->pm_HugeSectors == 0) 571 || (pmp->pm_FATsecs == 0) 572 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) 573 ) { 574 error = EINVAL; 575 goto error_exit; 576 } 577 578 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 579 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 580 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 581 SecPerClust *= pmp->pm_BlkPerSec; 582 583 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 584 585 if (FAT32(pmp)) { 586 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 587 pmp->pm_firstcluster = pmp->pm_fatblk 588 + (pmp->pm_FATs * pmp->pm_FATsecs); 589 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 590 } else { 591 pmp->pm_rootdirblk = pmp->pm_fatblk + 592 (pmp->pm_FATs * pmp->pm_FATsecs); 593 pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts * 594 sizeof(struct direntry), DEV_BSIZE); /* in blocks */ 595 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 596 } 597 598 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 599 SecPerClust + 1; 600 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 601 602 if (pmp->pm_fatmask == 0) { 603 if (pmp->pm_maxcluster 604 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 605 /* 606 * This will usually be a floppy disk. This size makes 607 * sure that one fat entry will not be split across 608 * multiple blocks. 609 */ 610 pmp->pm_fatmask = FAT12_MASK; 611 pmp->pm_fatmult = 3; 612 pmp->pm_fatdiv = 2; 613 } else { 614 pmp->pm_fatmask = FAT16_MASK; 615 pmp->pm_fatmult = 2; 616 pmp->pm_fatdiv = 1; 617 } 618 } 619 620 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 621 if (pmp->pm_maxcluster >= clusters) { 622#ifdef MSDOSFS_DEBUG 623 printf("Warning: number of clusters (%ld) exceeds FAT " 624 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 625#endif 626 pmp->pm_maxcluster = clusters - 1; 627 } 628 629 if (FAT12(pmp)) 630 pmp->pm_fatblocksize = 3 * 512; 631 else 632 pmp->pm_fatblocksize = PAGE_SIZE; 633 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 634 pmp->pm_BytesPerSec); 635 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 636 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 637 638 /* 639 * Compute mask and shift value for isolating cluster relative byte 640 * offsets and cluster numbers from a file offset. 641 */ 642 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 643 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 644 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 645 646 /* 647 * Check for valid cluster size 648 * must be a power of 2 649 */ 650 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 651 error = EINVAL; 652 goto error_exit; 653 } 654 655 /* 656 * Release the bootsector buffer. 657 */ 658 brelse(bp); 659 bp = NULL; 660 661 /* 662 * Check the fsinfo sector if we have one. Silently fix up our 663 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 664 * or too large. Ignore fp->fsinfree for now, since we need to 665 * read the entire FAT anyway to fill the inuse map. 666 */ 667 if (pmp->pm_fsinfo) { 668 struct fsinfo *fp; 669 670 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 671 NOCRED, &bp)) != 0) 672 goto error_exit; 673 fp = (struct fsinfo *)bp->b_data; 674 if (!bcmp(fp->fsisig1, "RRaA", 4) 675 && !bcmp(fp->fsisig2, "rrAa", 4) 676 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 677 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 678 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 679 pmp->pm_nxtfree = CLUST_FIRST; 680 } else 681 pmp->pm_fsinfo = 0; 682 brelse(bp); 683 bp = NULL; 684 } 685 686 /* 687 * Finish initializing pmp->pm_nxtfree (just in case the first few 688 * sectors aren't properly reserved in the FAT). This completes 689 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 690 * value if there is no fsinfo. We will use pmp->pm_nxtfree 691 * internally even if there is no fsinfo. 692 */ 693 if (pmp->pm_nxtfree < CLUST_FIRST) 694 pmp->pm_nxtfree = CLUST_FIRST; 695 696 /* 697 * Allocate memory for the bitmap of allocated clusters, and then 698 * fill it in. 699 */ 700 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 701 * sizeof(*pmp->pm_inusemap), 702 M_MSDOSFSFAT, M_WAITOK); 703 704 /* 705 * fillinusemap() needs pm_devvp. 706 */ 707 pmp->pm_devvp = devvp; 708 pmp->pm_dev = dev; 709 710 /* 711 * Have the inuse map filled in. 712 */ 713 MSDOSFS_LOCK_MP(pmp); 714 error = fillinusemap(pmp); 715 MSDOSFS_UNLOCK_MP(pmp); 716 if (error != 0) 717 goto error_exit; 718 719 /* 720 * If they want fat updates to be synchronous then let them suffer 721 * the performance degradation in exchange for the on disk copy of 722 * the fat being correct just about all the time. I suppose this 723 * would be a good thing to turn on if the kernel is still flakey. 724 */ 725 if (mp->mnt_flag & MNT_SYNCHRONOUS) 726 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 727 728 /* 729 * Finish up. 730 */ 731 if (ronly) 732 pmp->pm_flags |= MSDOSFSMNT_RONLY; 733 else { 734 if ((error = markvoldirty(pmp, 1)) != 0) { 735 (void)markvoldirty(pmp, 0); 736 goto error_exit; 737 } 738 pmp->pm_fmod = 1; 739 } 740 mp->mnt_data = pmp; 741 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 742 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 743 MNT_ILOCK(mp); 744 mp->mnt_flag |= MNT_LOCAL; 745 mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF; 746 MNT_IUNLOCK(mp); 747 748 if (pmp->pm_flags & MSDOSFS_LARGEFS) 749 msdosfs_fileno_init(mp); 750 751 return 0; 752 753error_exit: 754 if (bp) 755 brelse(bp); 756 if (cp != NULL) { 757 g_topology_lock(); 758 g_vfs_close(cp); 759 g_topology_unlock(); 760 } 761 if (pmp) { 762 lockdestroy(&pmp->pm_fatlock); 763 free(pmp->pm_inusemap, M_MSDOSFSFAT); 764 free(pmp, M_MSDOSFSMNT); 765 mp->mnt_data = NULL; 766 } 767 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 768 dev_rel(dev); 769 return (error); 770} 771 772/* 773 * Unmount the filesystem described by mp. 774 */ 775static int 776msdosfs_unmount(struct mount *mp, int mntflags) 777{ 778 struct msdosfsmount *pmp; 779 int error, flags; 780 781 error = flags = 0; 782 pmp = VFSTOMSDOSFS(mp); 783 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) 784 error = msdosfs_sync(mp, MNT_WAIT); 785 if ((mntflags & MNT_FORCE) != 0) 786 flags |= FORCECLOSE; 787 else if (error != 0) 788 return (error); 789 error = vflush(mp, 0, flags, curthread); 790 if (error != 0 && error != ENXIO) 791 return (error); 792 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 793 error = markvoldirty(pmp, 0); 794 if (error && error != ENXIO) { 795 (void)markvoldirty(pmp, 1); 796 return (error); 797 } 798 } 799 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 800 if (pmp->pm_w2u) 801 msdosfs_iconv->close(pmp->pm_w2u); 802 if (pmp->pm_u2w) 803 msdosfs_iconv->close(pmp->pm_u2w); 804 if (pmp->pm_d2u) 805 msdosfs_iconv->close(pmp->pm_d2u); 806 if (pmp->pm_u2d) 807 msdosfs_iconv->close(pmp->pm_u2d); 808 } 809 810#ifdef MSDOSFS_DEBUG 811 { 812 struct vnode *vp = pmp->pm_devvp; 813 struct bufobj *bo; 814 815 bo = &vp->v_bufobj; 816 BO_LOCK(bo); 817 VI_LOCK(vp); 818 vn_printf(vp, 819 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 820 printf("freef %p, freeb %p, mount %p\n", 821 TAILQ_NEXT(vp, v_actfreelist), vp->v_actfreelist.tqe_prev, 822 vp->v_mount); 823 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 824 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 825 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 826 vp->v_bufobj.bo_numoutput, vp->v_type); 827 VI_UNLOCK(vp); 828 BO_UNLOCK(bo); 829 } 830#endif 831 g_topology_lock(); 832 g_vfs_close(pmp->pm_cp); 833 g_topology_unlock(); 834 atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0); 835 vrele(pmp->pm_devvp); 836 dev_rel(pmp->pm_dev); 837 free(pmp->pm_inusemap, M_MSDOSFSFAT); 838 if (pmp->pm_flags & MSDOSFS_LARGEFS) 839 msdosfs_fileno_free(mp); 840 lockdestroy(&pmp->pm_fatlock); 841 free(pmp, M_MSDOSFSMNT); 842 mp->mnt_data = NULL; 843 MNT_ILOCK(mp); 844 mp->mnt_flag &= ~MNT_LOCAL; 845 MNT_IUNLOCK(mp); 846 return (error); 847} 848 849static int 850msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 851{ 852 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 853 struct denode *ndep; 854 int error; 855 856#ifdef MSDOSFS_DEBUG 857 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 858#endif 859 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 860 if (error) 861 return (error); 862 *vpp = DETOV(ndep); 863 return (0); 864} 865 866static int 867msdosfs_statfs(struct mount *mp, struct statfs *sbp) 868{ 869 struct msdosfsmount *pmp; 870 871 pmp = VFSTOMSDOSFS(mp); 872 sbp->f_bsize = pmp->pm_bpcluster; 873 sbp->f_iosize = pmp->pm_bpcluster; 874 sbp->f_blocks = pmp->pm_maxcluster + 1; 875 sbp->f_bfree = pmp->pm_freeclustercount; 876 sbp->f_bavail = pmp->pm_freeclustercount; 877 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 878 sbp->f_ffree = 0; /* what to put in here? */ 879 return (0); 880} 881 882/* 883 * If we have an FSInfo block, update it. 884 */ 885static int 886msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) 887{ 888 struct fsinfo *fp; 889 struct buf *bp; 890 int error; 891 892 MSDOSFS_LOCK_MP(pmp); 893 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { 894 error = 0; 895 goto unlock; 896 } 897 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 898 NOCRED, &bp); 899 if (error != 0) { 900 brelse(bp); 901 goto unlock; 902 } 903 fp = (struct fsinfo *)bp->b_data; 904 putulong(fp->fsinfree, pmp->pm_freeclustercount); 905 putulong(fp->fsinxtfree, pmp->pm_nxtfree); 906 pmp->pm_flags &= ~MSDOSFS_FSIMOD; 907 if (waitfor == MNT_WAIT) 908 error = bwrite(bp); 909 else 910 bawrite(bp); 911unlock: 912 MSDOSFS_UNLOCK_MP(pmp); 913 return (error); 914} 915 916static int 917msdosfs_sync(struct mount *mp, int waitfor) 918{ 919 struct vnode *vp, *nvp; 920 struct thread *td; 921 struct denode *dep; 922 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 923 int error, allerror = 0; 924 925 td = curthread; 926 927 /* 928 * If we ever switch to not updating all of the fats all the time, 929 * this would be the place to update them from the first one. 930 */ 931 if (pmp->pm_fmod != 0) { 932 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 933 panic("msdosfs_sync: rofs mod"); 934 else { 935 /* update fats here */ 936 } 937 } 938 /* 939 * Write back each (modified) denode. 940 */ 941loop: 942 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { 943 if (vp->v_type == VNON) { 944 VI_UNLOCK(vp); 945 continue; 946 } 947 dep = VTODE(vp); 948 if ((dep->de_flag & 949 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 950 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 951 waitfor == MNT_LAZY)) { 952 VI_UNLOCK(vp); 953 continue; 954 } 955 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 956 if (error) { 957 if (error == ENOENT) 958 goto loop; 959 continue; 960 } 961 error = VOP_FSYNC(vp, waitfor, td); 962 if (error) 963 allerror = error; 964 VOP_UNLOCK(vp, 0); 965 vrele(vp); 966 } 967 968 /* 969 * Flush filesystem control info. 970 */ 971 if (waitfor != MNT_LAZY) { 972 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 973 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 974 if (error) 975 allerror = error; 976 VOP_UNLOCK(pmp->pm_devvp, 0); 977 } 978 979 error = msdosfs_fsiflush(pmp, waitfor); 980 if (error != 0) 981 allerror = error; 982 return (allerror); 983} 984 985static int 986msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) 987{ 988 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 989 struct defid *defhp = (struct defid *) fhp; 990 struct denode *dep; 991 int error; 992 993 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 994 if (error) { 995 *vpp = NULLVP; 996 return (error); 997 } 998 *vpp = DETOV(dep); 999 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 1000 return (0); 1001} 1002 1003static struct vfsops msdosfs_vfsops = { 1004 .vfs_fhtovp = msdosfs_fhtovp, 1005 .vfs_mount = msdosfs_mount, 1006 .vfs_cmount = msdosfs_cmount, 1007 .vfs_root = msdosfs_root, 1008 .vfs_statfs = msdosfs_statfs, 1009 .vfs_sync = msdosfs_sync, 1010 .vfs_unmount = msdosfs_unmount, 1011}; 1012 1013VFS_SET(msdosfs_vfsops, msdosfs, 0); 1014MODULE_VERSION(msdosfs, 1); 1015