msdosfs_vfsops.c revision 171731
1/* $FreeBSD: head/sys/fs/msdosfs/msdosfs_vfsops.c 171731 2007-08-05 12:58:34Z bde $ */ 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/conf.h> 54#include <sys/namei.h> 55#include <sys/priv.h> 56#include <sys/proc.h> 57#include <sys/kernel.h> 58#include <sys/vnode.h> 59#include <sys/mount.h> 60#include <sys/bio.h> 61#include <sys/buf.h> 62#include <sys/fcntl.h> 63#include <sys/malloc.h> 64#include <sys/stat.h> /* defines ALLPERMS */ 65#include <sys/iconv.h> 66#include <sys/mutex.h> 67 68#include <fs/msdosfs/bpb.h> 69#include <fs/msdosfs/bootsect.h> 70#include <fs/msdosfs/msdosfsmount.h> 71#include <fs/msdosfs/direntry.h> 72#include <fs/msdosfs/denode.h> 73#include <fs/msdosfs/fat.h> 74 75#include <geom/geom.h> 76#include <geom/geom_vfs.h> 77 78/* List of mount options we support */ 79static const char *msdosfs_opts[] = { 80 "from", 81 "atime", "export", "force", "sync", 82 "uid", "gid", "mask", "dirmask", 83 "shortname", "shortnames", "longname", "longnames", "nowin95", "win95", 84 "kiconv", "cs_win", "cs_dos", "cs_local", "large", 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 = NULL; 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 191 : MSDOSFSMNT_SHORTNAME; 192 vput(rootvp); 193 } 194 } 195 return 0; 196} 197 198static int 199msdosfs_cmount(struct mntarg *ma, void *data, int flags, struct thread *td) 200{ 201 struct msdosfs_args args; 202 int error; 203 204 if (data == NULL) 205 return (EINVAL); 206 error = copyin(data, &args, sizeof args); 207 if (error) 208 return (error); 209 210 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 211 ma = mount_arg(ma, "export", &args.export, sizeof args.export); 212 ma = mount_argf(ma, "uid", "%d", args.uid); 213 ma = mount_argf(ma, "gid", "%d", args.gid); 214 ma = mount_argf(ma, "mask", "%d", args.mask); 215 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 216 217 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 218 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 219 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 220 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 221 222 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 223 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 224 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 225 226 error = kernel_mount(ma, flags); 227 228 return (error); 229} 230 231/* 232 * mp - path - addr in user space of mount point (ie /usr or whatever) 233 * data - addr in user space of mount params including the name of the block 234 * special file to treat as a filesystem. 235 */ 236static int 237msdosfs_mount(struct mount *mp, struct thread *td) 238{ 239 struct vnode *devvp; /* vnode for blk device to mount */ 240 /* msdosfs specific mount control block */ 241 struct msdosfsmount *pmp = NULL; 242 struct nameidata ndp; 243 int error, flags; 244 mode_t accessmode; 245 char *from; 246 247 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 248 return (EINVAL); 249 250 /* 251 * If updating, check whether changing from read-only to 252 * read/write; if there is no device name, that's all we do. 253 */ 254 if (mp->mnt_flag & MNT_UPDATE) { 255 int ro_to_rw = 0; 256 pmp = VFSTOMSDOSFS(mp); 257 258 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) { 259 /* 260 * Forbid export requests if filesystem has 261 * MSDOSFS_LARGEFS flag set. 262 */ 263 if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) { 264 vfs_mount_error(mp, 265 "MSDOSFS_LARGEFS flag set, cannot export"); 266 return (EOPNOTSUPP); 267 } 268 } 269 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 270 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 271 error = VFS_SYNC(mp, MNT_WAIT, td); 272 if (error) 273 return (error); 274 flags = WRITECLOSE; 275 if (mp->mnt_flag & MNT_FORCE) 276 flags |= FORCECLOSE; 277 error = vflush(mp, 0, flags, td); 278 if (error) 279 return (error); 280 DROP_GIANT(); 281 g_topology_lock(); 282 error = g_access(pmp->pm_cp, 0, -1, 0); 283 g_topology_unlock(); 284 PICKUP_GIANT(); 285 if (error) 286 return (error); 287 288 /* Now the volume is clean. Mark it. */ 289 error = markvoldirty(pmp, 0); 290 if (error && (flags & FORCECLOSE) == 0) 291 return (error); 292 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 293 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 294 /* 295 * If upgrade to read-write by non-root, then verify 296 * that user has necessary permissions on the device. 297 */ 298 devvp = pmp->pm_devvp; 299 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td); 300 error = VOP_ACCESS(devvp, VREAD | VWRITE, 301 td->td_ucred, td); 302 if (error) 303 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 304 if (error) { 305 VOP_UNLOCK(devvp, 0, td); 306 return (error); 307 } 308 VOP_UNLOCK(devvp, 0, td); 309 DROP_GIANT(); 310 g_topology_lock(); 311 error = g_access(pmp->pm_cp, 0, 1, 0); 312 g_topology_unlock(); 313 PICKUP_GIANT(); 314 if (error) 315 return (error); 316 317 ro_to_rw = 1; 318 } 319 vfs_flagopt(mp->mnt_optnew, "ro", 320 &pmp->pm_flags, MSDOSFSMNT_RONLY); 321 vfs_flagopt(mp->mnt_optnew, "ro", 322 &mp->mnt_flag, MNT_RDONLY); 323 324 if (ro_to_rw) { 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 accessmode = VREAD; 353 if ((mp->mnt_flag & MNT_RDONLY) == 0) 354 accessmode |= VWRITE; 355 error = VOP_ACCESS(devvp, accessmode, 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, td); 364#ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 365 pmp = VFSTOMSDOSFS(mp); 366#endif 367 } else { 368 if (devvp != pmp->pm_devvp) 369 error = EINVAL; /* XXX needs translation */ 370 else 371 vput(devvp); 372 } 373 if (error) { 374 vrele(devvp); 375 return (error); 376 } 377 378 error = update_mp(mp, td); 379 if (error) { 380 if ((mp->mnt_flag & MNT_UPDATE) == 0) 381 msdosfs_unmount(mp, MNT_FORCE, td); 382 return error; 383 } 384 385 vfs_mountedfrom(mp, from); 386#ifdef MSDOSFS_DEBUG 387 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 388#endif 389 return (0); 390} 391 392static int 393mountmsdosfs(struct vnode *devvp, struct mount *mp, struct thread *td) 394{ 395 struct msdosfsmount *pmp; 396 struct buf *bp; 397 struct cdev *dev = devvp->v_rdev; 398 union bootsector *bsp; 399 struct byte_bpb33 *b33; 400 struct byte_bpb50 *b50; 401 struct byte_bpb710 *b710; 402 u_int8_t SecPerClust; 403 u_long clusters; 404 int ronly, error; 405 struct g_consumer *cp; 406 struct bufobj *bo; 407 408 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 409 /* XXX: use VOP_ACCESS to check FS perms */ 410 DROP_GIANT(); 411 g_topology_lock(); 412 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 413 g_topology_unlock(); 414 PICKUP_GIANT(); 415 VOP_UNLOCK(devvp, 0, td); 416 if (error) 417 return (error); 418 419 bo = &devvp->v_bufobj; 420 bp = NULL; /* both used in error_exit */ 421 pmp = NULL; 422 423 /* 424 * Read the boot sector of the filesystem, and then check the 425 * boot signature. If not a dos boot sector then error out. 426 * 427 * NOTE: 8192 is a magic size that works for ffs. 428 */ 429 error = bread(devvp, 0, 8192, NOCRED, &bp); 430 if (error) 431 goto error_exit; 432 bp->b_flags |= B_AGE; 433 bsp = (union bootsector *)bp->b_data; 434 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 435 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 436 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 437 438#ifndef MSDOSFS_NOCHECKSIG 439 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 440 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 441 error = EINVAL; 442 goto error_exit; 443 } 444#endif 445 446 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 447 pmp->pm_mountp = mp; 448 pmp->pm_cp = cp; 449 pmp->pm_bo = bo; 450 451 /* 452 * Initialize ownerships and permissions, since nothing else will 453 * initialize them iff we are mounting root. 454 */ 455 pmp->pm_uid = UID_ROOT; 456 pmp->pm_gid = GID_WHEEL; 457 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 458 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 459 460 /* 461 * Experimental support for large MS-DOS filesystems. 462 * WARNING: This uses at least 32 bytes of kernel memory (which is not 463 * reclaimed until the FS is unmounted) for each file on disk to map 464 * between the 32-bit inode numbers used by VFS and the 64-bit 465 * pseudo-inode numbers used internally by msdosfs. This is only 466 * safe to use in certain controlled situations (e.g. read-only FS 467 * with less than 1 million files). 468 * Since the mappings do not persist across unmounts (or reboots), these 469 * filesystems are not suitable for exporting through NFS, or any other 470 * application that requires fixed inode numbers. 471 */ 472 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, 473 MSDOSFS_LARGEFS); 474 475 /* 476 * Compute several useful quantities from the bpb in the 477 * bootsector. Copy in the dos 5 variant of the bpb then fix up 478 * the fields that are different between dos 5 and dos 3.3. 479 */ 480 SecPerClust = b50->bpbSecPerClust; 481 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 482 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 483 error = EINVAL; 484 goto error_exit; 485 } 486 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 487 pmp->pm_FATs = b50->bpbFATs; 488 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 489 pmp->pm_Sectors = getushort(b50->bpbSectors); 490 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 491 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 492 pmp->pm_Heads = getushort(b50->bpbHeads); 493 pmp->pm_Media = b50->bpbMedia; 494 495 /* calculate the ratio of sector size to DEV_BSIZE */ 496 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 497 498 /* XXX - We should probably check more values here */ 499 if (!pmp->pm_BytesPerSec || !SecPerClust 500 || !pmp->pm_Heads 501#ifdef PC98 502 || !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 255) { 503#else 504 || !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) { 505#endif 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 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) { 518 if (pmp->pm_HugeSectors > 0xffffffff / 519 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) { 520 /* 521 * We cannot deal currently with this size of disk 522 * due to fileid limitations (see msdosfs_getattr and 523 * msdosfs_readdir) 524 */ 525 error = EINVAL; 526 vfs_mount_error(mp, 527 "Disk too big, try '-o large' mount option"); 528 goto error_exit; 529 } 530 } 531 532 if (pmp->pm_RootDirEnts == 0) { 533 if (pmp->pm_Sectors 534 || pmp->pm_FATsecs 535 || getushort(b710->bpbFSVers)) { 536 error = EINVAL; 537 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 538 goto error_exit; 539 } 540 pmp->pm_fatmask = FAT32_MASK; 541 pmp->pm_fatmult = 4; 542 pmp->pm_fatdiv = 1; 543 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 544 if (getushort(b710->bpbExtFlags) & FATMIRROR) 545 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 546 else 547 pmp->pm_flags |= MSDOSFS_FATMIRROR; 548 } else 549 pmp->pm_flags |= MSDOSFS_FATMIRROR; 550 551 /* 552 * Check a few values (could do some more): 553 * - logical sector size: power of 2, >= block size 554 * - sectors per cluster: power of 2, >= 1 555 * - number of sectors: >= 1, <= size of partition 556 * - number of FAT sectors: >= 1 557 */ 558 if ( (SecPerClust == 0) 559 || (SecPerClust & (SecPerClust - 1)) 560 || (pmp->pm_BytesPerSec < DEV_BSIZE) 561 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 562 || (pmp->pm_HugeSectors == 0) 563 || (pmp->pm_FATsecs == 0) 564 ) { 565 error = EINVAL; 566 goto error_exit; 567 } 568 569 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 570 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 571 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 572 SecPerClust *= pmp->pm_BlkPerSec; 573 574 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 575 576 if (FAT32(pmp)) { 577 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 578 pmp->pm_firstcluster = pmp->pm_fatblk 579 + (pmp->pm_FATs * pmp->pm_FATsecs); 580 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 581 } else { 582 pmp->pm_rootdirblk = pmp->pm_fatblk + 583 (pmp->pm_FATs * pmp->pm_FATsecs); 584 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 585 + DEV_BSIZE - 1) 586 / DEV_BSIZE; /* in blocks */ 587 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 588 } 589 590 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 591 SecPerClust + 1; 592 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 593 594 if (pmp->pm_fatmask == 0) { 595 if (pmp->pm_maxcluster 596 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 597 /* 598 * This will usually be a floppy disk. This size makes 599 * sure that one fat entry will not be split across 600 * multiple blocks. 601 */ 602 pmp->pm_fatmask = FAT12_MASK; 603 pmp->pm_fatmult = 3; 604 pmp->pm_fatdiv = 2; 605 } else { 606 pmp->pm_fatmask = FAT16_MASK; 607 pmp->pm_fatmult = 2; 608 pmp->pm_fatdiv = 1; 609 } 610 } 611 612 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 613 if (pmp->pm_maxcluster >= clusters) { 614 printf("Warning: number of clusters (%ld) exceeds FAT " 615 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 616 pmp->pm_maxcluster = clusters - 1; 617 } 618 619 if (FAT12(pmp)) 620 pmp->pm_fatblocksize = 3 * 512; 621 else 622 pmp->pm_fatblocksize = PAGE_SIZE; 623 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 624 pmp->pm_BytesPerSec); 625 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 626 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 627 628 /* 629 * Compute mask and shift value for isolating cluster relative byte 630 * offsets and cluster numbers from a file offset. 631 */ 632 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 633 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 634 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 635 636 /* 637 * Check for valid cluster size 638 * must be a power of 2 639 */ 640 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 641 error = EINVAL; 642 goto error_exit; 643 } 644 645 /* 646 * Release the bootsector buffer. 647 */ 648 brelse(bp); 649 bp = NULL; 650 651 /* 652 * Check the fsinfo sector if we have one. Silently fix up our 653 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 654 * or too large. Ignore fp->fsinfree for now, since we need to 655 * read the entire FAT anyway to fill the inuse map. 656 */ 657 if (pmp->pm_fsinfo) { 658 struct fsinfo *fp; 659 660 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 661 NOCRED, &bp)) != 0) 662 goto error_exit; 663 fp = (struct fsinfo *)bp->b_data; 664 if (!bcmp(fp->fsisig1, "RRaA", 4) 665 && !bcmp(fp->fsisig2, "rrAa", 4) 666 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 667 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 668 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 669 pmp->pm_nxtfree = CLUST_FIRST; 670 } else 671 pmp->pm_fsinfo = 0; 672 brelse(bp); 673 bp = NULL; 674 } 675 676 /* 677 * Finish initializing pmp->pm_nxtfree (just in case the first few 678 * sectors aren't properly reserved in the FAT). This completes 679 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 680 * value if there is no fsinfo. We will use pmp->pm_nxtfree 681 * internally even if there is no fsinfo. 682 */ 683 if (pmp->pm_nxtfree < CLUST_FIRST) 684 pmp->pm_nxtfree = CLUST_FIRST; 685 686 /* 687 * Allocate memory for the bitmap of allocated clusters, and then 688 * fill it in. 689 */ 690 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 691 * sizeof(*pmp->pm_inusemap), 692 M_MSDOSFSFAT, M_WAITOK); 693 694 /* 695 * fillinusemap() needs pm_devvp. 696 */ 697 pmp->pm_devvp = devvp; 698 699 /* 700 * Have the inuse map filled in. 701 */ 702 if ((error = fillinusemap(pmp)) != 0) 703 goto error_exit; 704 705 /* 706 * If they want fat updates to be synchronous then let them suffer 707 * the performance degradation in exchange for the on disk copy of 708 * the fat being correct just about all the time. I suppose this 709 * would be a good thing to turn on if the kernel is still flakey. 710 */ 711 if (mp->mnt_flag & MNT_SYNCHRONOUS) 712 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 713 714 /* 715 * Finish up. 716 */ 717 if (ronly) 718 pmp->pm_flags |= MSDOSFSMNT_RONLY; 719 else { 720 /* Mark the volume dirty while it is mounted read/write. */ 721 if ((error = markvoldirty(pmp, 1)) != 0) 722 goto error_exit; 723 pmp->pm_fmod = 1; 724 } 725 mp->mnt_data = (qaddr_t) pmp; 726 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 727 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 728 MNT_ILOCK(mp); 729 mp->mnt_flag |= MNT_LOCAL; 730 MNT_IUNLOCK(mp); 731 732 if (pmp->pm_flags & MSDOSFS_LARGEFS) 733 msdosfs_fileno_init(mp); 734 735 return 0; 736 737error_exit: 738 if (bp) 739 brelse(bp); 740 if (cp != NULL) { 741 DROP_GIANT(); 742 g_topology_lock(); 743 g_vfs_close(cp, td); 744 g_topology_unlock(); 745 PICKUP_GIANT(); 746 } 747 if (pmp) { 748 if (pmp->pm_inusemap) 749 free(pmp->pm_inusemap, M_MSDOSFSFAT); 750 free(pmp, M_MSDOSFSMNT); 751 mp->mnt_data = (qaddr_t)0; 752 } 753 return (error); 754} 755 756/* 757 * Unmount the filesystem described by mp. 758 */ 759static int 760msdosfs_unmount(struct mount *mp, int mntflags, struct thread *td) 761{ 762 struct msdosfsmount *pmp; 763 int error, flags; 764 765 flags = 0; 766 if (mntflags & MNT_FORCE) 767 flags |= FORCECLOSE; 768 error = vflush(mp, 0, flags, td); 769 if (error) 770 return error; 771 pmp = VFSTOMSDOSFS(mp); 772 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 773 if (pmp->pm_w2u) 774 msdosfs_iconv->close(pmp->pm_w2u); 775 if (pmp->pm_u2w) 776 msdosfs_iconv->close(pmp->pm_u2w); 777 if (pmp->pm_d2u) 778 msdosfs_iconv->close(pmp->pm_d2u); 779 if (pmp->pm_u2d) 780 msdosfs_iconv->close(pmp->pm_u2d); 781 } 782 783 /* If the volume was mounted read/write, mark it clean now. */ 784 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 785 error = markvoldirty(pmp, 0); 786 if (error && (flags & FORCECLOSE) == 0) 787 return (error); 788 } 789#ifdef MSDOSFS_DEBUG 790 { 791 struct vnode *vp = pmp->pm_devvp; 792 793 VI_LOCK(vp); 794 vn_printf(vp, 795 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 796 printf("freef %p, freeb %p, mount %p\n", 797 TAILQ_NEXT(vp, v_freelist), vp->v_freelist.tqe_prev, 798 vp->v_mount); 799 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 800 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 801 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 802 vp->v_bufobj.bo_numoutput, vp->v_type); 803 VI_UNLOCK(vp); 804 } 805#endif 806 DROP_GIANT(); 807 g_topology_lock(); 808 g_vfs_close(pmp->pm_cp, td); 809 g_topology_unlock(); 810 PICKUP_GIANT(); 811 vrele(pmp->pm_devvp); 812 free(pmp->pm_inusemap, M_MSDOSFSFAT); 813 if (pmp->pm_flags & MSDOSFS_LARGEFS) { 814 msdosfs_fileno_free(mp); 815 } 816 free(pmp, M_MSDOSFSMNT); 817 mp->mnt_data = (qaddr_t)0; 818 MNT_ILOCK(mp); 819 mp->mnt_flag &= ~MNT_LOCAL; 820 MNT_IUNLOCK(mp); 821 return (error); 822} 823 824static int 825msdosfs_root(struct mount *mp, int flags, struct vnode **vpp, struct thread *td) 826{ 827 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 828 struct denode *ndep; 829 int error; 830 831#ifdef MSDOSFS_DEBUG 832 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 833#endif 834 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 835 if (error) 836 return (error); 837 *vpp = DETOV(ndep); 838 return (0); 839} 840 841static int 842msdosfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 843{ 844 struct msdosfsmount *pmp; 845 846 pmp = VFSTOMSDOSFS(mp); 847 sbp->f_bsize = pmp->pm_bpcluster; 848 sbp->f_iosize = pmp->pm_bpcluster; 849 sbp->f_blocks = pmp->pm_maxcluster + 1; 850 sbp->f_bfree = pmp->pm_freeclustercount; 851 sbp->f_bavail = pmp->pm_freeclustercount; 852 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 853 sbp->f_ffree = 0; /* what to put in here? */ 854 return (0); 855} 856 857static int 858msdosfs_sync(struct mount *mp, int waitfor, struct thread *td) 859{ 860 struct vnode *vp, *nvp; 861 struct denode *dep; 862 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 863 int error, allerror = 0; 864 865 /* 866 * If we ever switch to not updating all of the fats all the time, 867 * this would be the place to update them from the first one. 868 */ 869 if (pmp->pm_fmod != 0) { 870 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 871 panic("msdosfs_sync: rofs mod"); 872 else { 873 /* update fats here */ 874 } 875 } 876 /* 877 * Write back each (modified) denode. 878 */ 879 MNT_ILOCK(mp); 880loop: 881 MNT_VNODE_FOREACH(vp, mp, nvp) { 882 VI_LOCK(vp); 883 if (vp->v_type == VNON || (vp->v_iflag & VI_DOOMED)) { 884 VI_UNLOCK(vp); 885 continue; 886 } 887 MNT_IUNLOCK(mp); 888 dep = VTODE(vp); 889 if ((dep->de_flag & 890 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 891 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 892 waitfor == MNT_LAZY)) { 893 VI_UNLOCK(vp); 894 MNT_ILOCK(mp); 895 continue; 896 } 897 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 898 if (error) { 899 MNT_ILOCK(mp); 900 if (error == ENOENT) 901 goto loop; 902 continue; 903 } 904 error = VOP_FSYNC(vp, waitfor, td); 905 if (error) 906 allerror = error; 907 VOP_UNLOCK(vp, 0, td); 908 vrele(vp); 909 MNT_ILOCK(mp); 910 } 911 MNT_IUNLOCK(mp); 912 913 /* 914 * Flush filesystem control info. 915 */ 916 if (waitfor != MNT_LAZY) { 917 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY, td); 918 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 919 if (error) 920 allerror = error; 921 VOP_UNLOCK(pmp->pm_devvp, 0, td); 922 } 923 return (allerror); 924} 925 926static int 927msdosfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp) 928{ 929 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 930 struct defid *defhp = (struct defid *) fhp; 931 struct denode *dep; 932 int error; 933 934 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 935 if (error) { 936 *vpp = NULLVP; 937 return (error); 938 } 939 *vpp = DETOV(dep); 940 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 941 return (0); 942} 943 944static struct vfsops msdosfs_vfsops = { 945 .vfs_fhtovp = msdosfs_fhtovp, 946 .vfs_mount = msdosfs_mount, 947 .vfs_cmount = msdosfs_cmount, 948 .vfs_root = msdosfs_root, 949 .vfs_statfs = msdosfs_statfs, 950 .vfs_sync = msdosfs_sync, 951 .vfs_unmount = msdosfs_unmount, 952}; 953 954VFS_SET(msdosfs_vfsops, msdosfs, 0); 955MODULE_VERSION(msdosfs, 1); 956