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sys/fs/msdosfs/msdosfs_vfsops.c
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1 /* $FreeBSD$ */ 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 /* List of mount options we support */ 78 static const char *msdosfs_opts[] = { 79 "from", 80 "noatime", "export", "force", "sync", 81 "uid", "gid", "mask", "dirmask", 82 "shortname", "shortnames", "longname", "longnames", "nowin95", "win95", 83 "kiconv", "cs_win", "cs_dos", "cs_local", "large", 84 NULL 85 }; 86 87 #if 1 /*def PC98*/ 88 /* 89 * XXX - The boot signature formatted by NEC PC-98 DOS looks like a 90 * garbage or a random value :-{ 91 * If you want to use that broken-signatured media, define the 92 * following symbol even though PC/AT. 93 * (ex. mount PC-98 DOS formatted FD on PC/AT) 94 */ 95 #define MSDOSFS_NOCHECKSIG 96 #endif 97 98 MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); 99 static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); 100 101 struct iconv_functions *msdosfs_iconv; 102 103 static int update_mp(struct mount *mp, struct thread *td); 104 static int mountmsdosfs(struct vnode *devvp, struct mount *mp, 105 struct thread *td); 106 static vfs_fhtovp_t msdosfs_fhtovp; 107 static vfs_mount_t msdosfs_mount; 108 static vfs_root_t msdosfs_root; 109 static vfs_statfs_t msdosfs_statfs; 110 static vfs_sync_t msdosfs_sync; 111 static vfs_unmount_t msdosfs_unmount; 112 113 /* Maximum length of a character set name (arbitrary). */ 114 #define MAXCSLEN 64 115 116 static int 117 update_mp(struct mount *mp, struct thread *td) 118 { 119 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 120 void *dos, *win, *local; 121 int error, v; 122 123 if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { 124 if (msdosfs_iconv != NULL) { 125 error = vfs_getopt(mp->mnt_optnew, 126 "cs_win", &win, NULL); 127 if (!error) 128 error = vfs_getopt(mp->mnt_optnew, 129 "cs_local", &local, NULL); 130 if (!error) 131 error = vfs_getopt(mp->mnt_optnew, 132 "cs_dos", &dos, NULL); 133 if (!error) { 134 msdosfs_iconv->open(win, local, &pmp->pm_u2w); 135 msdosfs_iconv->open(local, win, &pmp->pm_w2u); 136 msdosfs_iconv->open(dos, local, &pmp->pm_u2d); 137 msdosfs_iconv->open(local, dos, &pmp->pm_d2u); 138 } 139 if (error != 0) 140 return (error); 141 } else { 142 pmp->pm_w2u = NULL; 143 pmp->pm_u2w = NULL; 144 pmp->pm_d2u = NULL; 145 pmp->pm_u2d = NULL; 146 } 147 } 148 149 if (1 == vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v)) 150 pmp->pm_gid = v; 151 if (1 == vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v)) 152 pmp->pm_uid = v; 153 if (1 == vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v)) 154 pmp->pm_mask = v & ALLPERMS; 155 if (1 == vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v)) 156 pmp->pm_dirmask = v & ALLPERMS; 157 vfs_flagopt(mp->mnt_optnew, "shortname", 158 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 159 vfs_flagopt(mp->mnt_optnew, "shortnames", 160 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 161 vfs_flagopt(mp->mnt_optnew, "longname", 162 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 163 vfs_flagopt(mp->mnt_optnew, "longnames", 164 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 165 vfs_flagopt(mp->mnt_optnew, "kiconv", 166 &pmp->pm_flags, MSDOSFSMNT_KICONV); 167 168 if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) 169 pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 170 else 171 pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; 172 173 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 174 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 175 else if (!(pmp->pm_flags & 176 (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) { 177 struct vnode *rootvp; 178 179 /* 180 * Try to divine whether to support Win'95 long filenames 181 */ 182 if (FAT32(pmp)) 183 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 184 else { 185 if ((error = 186 msdosfs_root(mp, LK_EXCLUSIVE, &rootvp, td)) != 0) 187 return error; 188 pmp->pm_flags |= findwin95(VTODE(rootvp)) ? 189 MSDOSFSMNT_LONGNAME : MSDOSFSMNT_SHORTNAME; 190 vput(rootvp); 191 } 192 } 193 return 0; 194 } 195 196 static int 197 msdosfs_cmount(struct mntarg *ma, void *data, int flags, struct thread *td) 198 { 199 struct msdosfs_args args; 200 int error; 201 202 if (data == NULL) 203 return (EINVAL); 204 error = copyin(data, &args, sizeof args); 205 if (error) 206 return (error); 207 208 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 209 ma = mount_arg(ma, "export", &args.export, sizeof args.export); 210 ma = mount_argf(ma, "uid", "%d", args.uid); 211 ma = mount_argf(ma, "gid", "%d", args.gid); 212 ma = mount_argf(ma, "mask", "%d", args.mask); 213 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 214 215 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 216 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 217 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 218 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 219 220 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 221 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 222 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 223 224 error = kernel_mount(ma, flags); 225 226 return (error); 227 } 228 229 /* 230 * mp - path - addr in user space of mount point (ie /usr or whatever) 231 * data - addr in user space of mount params including the name of the block 232 * special file to treat as a filesystem. 233 */ 234 static int 235 msdosfs_mount(struct mount *mp, struct thread *td) 236 { 237 struct vnode *devvp; /* vnode for blk device to mount */ 238 /* msdosfs specific mount control block */ 239 struct msdosfsmount *pmp = NULL; 240 struct nameidata ndp; 241 int error, flags; 242 mode_t accessmode; 243 char *from; 244 245 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 246 return (EINVAL); 247 248 /* 249 * If updating, check whether changing from read-only to 250 * read/write; if there is no device name, that's all we do. 251 */ 252 if (mp->mnt_flag & MNT_UPDATE) { 253 int ro_to_rw = 0; 254 255 pmp = VFSTOMSDOSFS(mp); 256 if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) { 257 /* 258 * Forbid export requests if filesystem has 259 * MSDOSFS_LARGEFS flag set. 260 */ 261 if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) { 262 vfs_mount_error(mp, 263 "MSDOSFS_LARGEFS flag set, cannot export"); 264 return (EOPNOTSUPP); 265 } 266 } 267 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 268 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 269 error = VFS_SYNC(mp, MNT_WAIT, td); 270 if (error) 271 return (error); 272 flags = WRITECLOSE; 273 if (mp->mnt_flag & MNT_FORCE) 274 flags |= FORCECLOSE; 275 error = vflush(mp, 0, flags, td); 276 if (error) 277 return (error); 278 DROP_GIANT(); 279 g_topology_lock(); 280 error = g_access(pmp->pm_cp, 0, -1, 0); 281 g_topology_unlock(); 282 PICKUP_GIANT(); 283 if (error) 284 return (error); 285 286 /* Now the volume is clean. Mark it. */ 287 error = markvoldirty(pmp, 0); 288 if (error && (flags & FORCECLOSE) == 0) 289 return (error); 290 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 291 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 292 /* 293 * If upgrade to read-write by non-root, then verify 294 * that user has necessary permissions on the device. 295 */ 296 devvp = pmp->pm_devvp; 297 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY, td); 298 error = VOP_ACCESS(devvp, VREAD | VWRITE, 299 td->td_ucred, td); 300 if (error) 301 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 302 if (error) { 303 VOP_UNLOCK(devvp, 0, td); 304 return (error); 305 } 306 VOP_UNLOCK(devvp, 0, td); 307 DROP_GIANT(); 308 g_topology_lock(); 309 error = g_access(pmp->pm_cp, 0, 1, 0); 310 g_topology_unlock(); 311 PICKUP_GIANT(); 312 if (error) 313 return (error); 314 315 ro_to_rw = 1; 316 } 317 vfs_flagopt(mp->mnt_optnew, "ro", 318 &pmp->pm_flags, MSDOSFSMNT_RONLY); 319 vfs_flagopt(mp->mnt_optnew, "ro", 320 &mp->mnt_flag, MNT_RDONLY); 321 322 if (ro_to_rw) { 323 /* Now that the volume is modifiable, mark it dirty. */ 324 error = markvoldirty(pmp, 1); 325 if (error) 326 return (error); 327 } 328 } 329 /* 330 * Not an update, or updating the name: look up the name 331 * and verify that it refers to a sensible disk device. 332 */ 333 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 334 return (EINVAL); 335 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 336 error = namei(&ndp); 337 if (error) 338 return (error); 339 devvp = ndp.ni_vp; 340 NDFREE(&ndp, NDF_ONLY_PNBUF); 341 342 if (!vn_isdisk(devvp, &error)) { 343 vput(devvp); 344 return (error); 345 } 346 /* 347 * If mount by non-root, then verify that user has necessary 348 * permissions on the device. 349 */ 350 accessmode = VREAD; 351 if ((mp->mnt_flag & MNT_RDONLY) == 0) 352 accessmode |= VWRITE; 353 error = VOP_ACCESS(devvp, accessmode, td->td_ucred, td); 354 if (error) 355 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 356 if (error) { 357 vput(devvp); 358 return (error); 359 } 360 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 361 error = mountmsdosfs(devvp, mp, td); 362 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 363 pmp = VFSTOMSDOSFS(mp); 364 #endif 365 } else { 366 if (devvp != pmp->pm_devvp) 367 error = EINVAL; /* XXX needs translation */ 368 else 369 vput(devvp); 370 } 371 if (error) { 372 vrele(devvp); 373 return (error); 374 } 375 376 error = update_mp(mp, td); 377 if (error) { 378 if ((mp->mnt_flag & MNT_UPDATE) == 0) 379 msdosfs_unmount(mp, MNT_FORCE, td); 380 return error; 381 } 382 383 vfs_mountedfrom(mp, from); 384 #ifdef MSDOSFS_DEBUG 385 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 386 #endif 387 return (0); 388 } 389 390 static int 391 mountmsdosfs(struct vnode *devvp, struct mount *mp, struct thread *td) 392 { 393 struct msdosfsmount *pmp; 394 struct buf *bp; 395 struct cdev *dev = devvp->v_rdev; 396 union bootsector *bsp; 397 struct byte_bpb33 *b33; 398 struct byte_bpb50 *b50; 399 struct byte_bpb710 *b710; 400 u_int8_t SecPerClust; 401 u_long clusters; 402 int ronly, error; 403 struct g_consumer *cp; 404 struct bufobj *bo; 405 406 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 407 /* XXX: use VOP_ACCESS to check FS perms */ 408 DROP_GIANT(); 409 g_topology_lock(); 410 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 411 g_topology_unlock(); 412 PICKUP_GIANT(); 413 VOP_UNLOCK(devvp, 0, td); 414 if (error) 415 return (error); 416 417 bo = &devvp->v_bufobj; 418 bp = NULL; /* This and pmp both used in error_exit. */ 419 pmp = NULL; 420 421 /* 422 * Read the boot sector of the filesystem, and then check the 423 * boot signature. If not a dos boot sector then error out. 424 * 425 * NOTE: 8192 is a magic size that works for ffs. 426 */ 427 error = bread(devvp, 0, 8192, NOCRED, &bp); 428 if (error) 429 goto error_exit; 430 bp->b_flags |= B_AGE; 431 bsp = (union bootsector *)bp->b_data; 432 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 433 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 434 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 435 436 #ifndef MSDOSFS_NOCHECKSIG 437 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 438 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 439 error = EINVAL; 440 goto error_exit; 441 } 442 #endif 443 444 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 445 pmp->pm_mountp = mp; 446 pmp->pm_cp = cp; 447 pmp->pm_bo = bo; 448 449 /* 450 * Initialize ownerships and permissions, since nothing else will 451 * initialize them iff we are mounting root. 452 */ 453 pmp->pm_uid = UID_ROOT; 454 pmp->pm_gid = GID_WHEEL; 455 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 456 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 457 458 /* 459 * Experimental support for large MS-DOS filesystems. 460 * WARNING: This uses at least 32 bytes of kernel memory (which is not 461 * reclaimed until the FS is unmounted) for each file on disk to map 462 * between the 32-bit inode numbers used by VFS and the 64-bit 463 * pseudo-inode numbers used internally by msdosfs. This is only 464 * safe to use in certain controlled situations (e.g. read-only FS 465 * with less than 1 million files). 466 * Since the mappings do not persist across unmounts (or reboots), these 467 * filesystems are not suitable for exporting through NFS, or any other 468 * application that requires fixed inode numbers. 469 */ 470 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS); 471 472 /* 473 * Compute several useful quantities from the bpb in the 474 * bootsector. Copy in the dos 5 variant of the bpb then fix up 475 * the fields that are different between dos 5 and dos 3.3. 476 */ 477 SecPerClust = b50->bpbSecPerClust; 478 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 479 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 480 error = EINVAL; 481 goto error_exit; 482 } 483 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 484 pmp->pm_FATs = b50->bpbFATs; 485 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 486 pmp->pm_Sectors = getushort(b50->bpbSectors); 487 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 488 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 489 pmp->pm_Heads = getushort(b50->bpbHeads); 490 pmp->pm_Media = b50->bpbMedia; 491 492 /* calculate the ratio of sector size to DEV_BSIZE */ 493 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 494 495 /* XXX - We should probably check more values here */ 496 if (!pmp->pm_BytesPerSec || !SecPerClust 497 || !pmp->pm_Heads 498 #ifdef PC98 499 || !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 255) { 500 #else 501 || !pmp->pm_SecPerTrack || pmp->pm_SecPerTrack > 63) { 502 #endif 503 error = EINVAL; 504 goto error_exit; 505 } 506 507 if (pmp->pm_Sectors == 0) { 508 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 509 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 510 } else { 511 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 512 pmp->pm_HugeSectors = pmp->pm_Sectors; 513 } 514 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) { 515 if (pmp->pm_HugeSectors > 0xffffffff / 516 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) { 517 /* 518 * We cannot deal currently with this size of disk 519 * due to fileid limitations (see msdosfs_getattr and 520 * msdosfs_readdir) 521 */ 522 error = EINVAL; 523 vfs_mount_error(mp, 524 "Disk too big, try '-o large' mount option"); 525 goto error_exit; 526 } 527 } 528 529 if (pmp->pm_RootDirEnts == 0) { 530 if (pmp->pm_Sectors 531 || pmp->pm_FATsecs 532 || getushort(b710->bpbFSVers)) { 533 error = EINVAL; 534 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 535 goto error_exit; 536 } 537 pmp->pm_fatmask = FAT32_MASK; 538 pmp->pm_fatmult = 4; 539 pmp->pm_fatdiv = 1; 540 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 541 if (getushort(b710->bpbExtFlags) & FATMIRROR) 542 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 543 else 544 pmp->pm_flags |= MSDOSFS_FATMIRROR; 545 } else 546 pmp->pm_flags |= MSDOSFS_FATMIRROR; 547 548 /* 549 * Check a few values (could do some more): 550 * - logical sector size: power of 2, >= block size 551 * - sectors per cluster: power of 2, >= 1 552 * - number of sectors: >= 1, <= size of partition 553 * - number of FAT sectors: >= 1 554 */ 555 if ( (SecPerClust == 0) 556 || (SecPerClust & (SecPerClust - 1)) 557 || (pmp->pm_BytesPerSec < DEV_BSIZE) 558 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 559 || (pmp->pm_HugeSectors == 0) 560 || (pmp->pm_FATsecs == 0) 561 ) { 562 error = EINVAL; 563 goto error_exit; 564 } 565 566 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 567 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 568 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 569 SecPerClust *= pmp->pm_BlkPerSec; 570 571 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 572 573 if (FAT32(pmp)) { 574 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 575 pmp->pm_firstcluster = pmp->pm_fatblk 576 + (pmp->pm_FATs * pmp->pm_FATsecs); 577 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 578 } else { 579 pmp->pm_rootdirblk = pmp->pm_fatblk + 580 (pmp->pm_FATs * pmp->pm_FATsecs); 581 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 582 + DEV_BSIZE - 1) 583 / DEV_BSIZE; /* in blocks */ 584 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 585 } 586 587 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 588 SecPerClust + 1; 589 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 590 591 if (pmp->pm_fatmask == 0) { 592 if (pmp->pm_maxcluster 593 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 594 /* 595 * This will usually be a floppy disk. This size makes 596 * sure that one fat entry will not be split across 597 * multiple blocks. 598 */ 599 pmp->pm_fatmask = FAT12_MASK; 600 pmp->pm_fatmult = 3; 601 pmp->pm_fatdiv = 2; 602 } else { 603 pmp->pm_fatmask = FAT16_MASK; 604 pmp->pm_fatmult = 2; 605 pmp->pm_fatdiv = 1; 606 } 607 } 608 609 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 610 if (pmp->pm_maxcluster >= clusters) { 611 printf("Warning: number of clusters (%ld) exceeds FAT " 612 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 613 pmp->pm_maxcluster = clusters - 1; 614 } 615 616 if (FAT12(pmp)) 617 pmp->pm_fatblocksize = 3 * 512; 618 else 619 pmp->pm_fatblocksize = PAGE_SIZE; 620 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 621 pmp->pm_BytesPerSec); 622 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 623 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 624 625 /* 626 * Compute mask and shift value for isolating cluster relative byte 627 * offsets and cluster numbers from a file offset. 628 */ 629 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 630 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 631 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 632 633 /* 634 * Check for valid cluster size 635 * must be a power of 2 636 */ 637 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 638 error = EINVAL; 639 goto error_exit; 640 } 641 642 /* 643 * Release the bootsector buffer. 644 */ 645 brelse(bp); 646 bp = NULL; 647 648 /* 649 * Check the fsinfo sector if we have one. Silently fix up our 650 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 651 * or too large. Ignore fp->fsinfree for now, since we need to 652 * read the entire FAT anyway to fill the inuse map. 653 */ 654 if (pmp->pm_fsinfo) { 655 struct fsinfo *fp; 656 657 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 658 NOCRED, &bp)) != 0) 659 goto error_exit; 660 fp = (struct fsinfo *)bp->b_data; 661 if (!bcmp(fp->fsisig1, "RRaA", 4) 662 && !bcmp(fp->fsisig2, "rrAa", 4) 663 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 664 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 665 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 666 pmp->pm_nxtfree = CLUST_FIRST; 667 } else 668 pmp->pm_fsinfo = 0; 669 brelse(bp); 670 bp = NULL; 671 } 672 673 /* 674 * Finish initializing pmp->pm_nxtfree (just in case the first few 675 * sectors aren't properly reserved in the FAT). This completes 676 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 677 * value if there is no fsinfo. We will use pmp->pm_nxtfree 678 * internally even if there is no fsinfo. 679 */ 680 if (pmp->pm_nxtfree < CLUST_FIRST) 681 pmp->pm_nxtfree = CLUST_FIRST; 682 683 /* 684 * Allocate memory for the bitmap of allocated clusters, and then 685 * fill it in. 686 */ 687 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 688 * sizeof(*pmp->pm_inusemap), 689 M_MSDOSFSFAT, M_WAITOK); 690 691 /* 692 * fillinusemap() needs pm_devvp. 693 */ 694 pmp->pm_devvp = devvp; 695 696 /* 697 * Have the inuse map filled in. 698 */ 699 if ((error = fillinusemap(pmp)) != 0) 700 goto error_exit; 701 702 /* 703 * If they want fat updates to be synchronous then let them suffer 704 * the performance degradation in exchange for the on disk copy of 705 * the fat being correct just about all the time. I suppose this 706 * would be a good thing to turn on if the kernel is still flakey. 707 */ 708 if (mp->mnt_flag & MNT_SYNCHRONOUS) 709 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 710 711 /* 712 * Finish up. 713 */ 714 if (ronly) 715 pmp->pm_flags |= MSDOSFSMNT_RONLY; 716 else { 717 /* Mark the volume dirty while it is mounted read/write. */ 718 if ((error = markvoldirty(pmp, 1)) != 0) 719 goto error_exit; 720 pmp->pm_fmod = 1; 721 } 722 mp->mnt_data = (qaddr_t) pmp; 723 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 724 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 725 MNT_ILOCK(mp); 726 mp->mnt_flag |= MNT_LOCAL; 727 MNT_IUNLOCK(mp); 728 729 if (pmp->pm_flags & MSDOSFS_LARGEFS) 730 msdosfs_fileno_init(mp); 731 732 return 0; 733 734 error_exit: 735 if (bp) 736 brelse(bp); 737 if (cp != NULL) { 738 DROP_GIANT(); 739 g_topology_lock(); 740 g_vfs_close(cp, td); 741 g_topology_unlock(); 742 PICKUP_GIANT(); 743 } 744 if (pmp) { 745 if (pmp->pm_inusemap) 746 free(pmp->pm_inusemap, M_MSDOSFSFAT); 747 free(pmp, M_MSDOSFSMNT); 748 mp->mnt_data = (qaddr_t)0; 749 } 750 return (error); 751 } 752 753 /* 754 * Unmount the filesystem described by mp. 755 */ 756 static int 757 msdosfs_unmount(struct mount *mp, int mntflags, struct thread *td) 758 { 759 struct msdosfsmount *pmp; 760 int error, flags; 761 762 flags = 0; 763 if (mntflags & MNT_FORCE) 764 flags |= FORCECLOSE; 765 error = vflush(mp, 0, flags, td); 766 if (error) 767 return error; 768 pmp = VFSTOMSDOSFS(mp); 769 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 770 if (pmp->pm_w2u) 771 msdosfs_iconv->close(pmp->pm_w2u); 772 if (pmp->pm_u2w) 773 msdosfs_iconv->close(pmp->pm_u2w); 774 if (pmp->pm_d2u) 775 msdosfs_iconv->close(pmp->pm_d2u); 776 if (pmp->pm_u2d) 777 msdosfs_iconv->close(pmp->pm_u2d); 778 } 779 780 /* If the volume was mounted read/write, mark it clean now. */ 781 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 782 error = markvoldirty(pmp, 0); 783 if (error && (flags & FORCECLOSE) == 0) 784 return (error); 785 } 786 #ifdef MSDOSFS_DEBUG 787 { 788 struct vnode *vp = pmp->pm_devvp; 789 790 VI_LOCK(vp); 791 vn_printf(vp, 792 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 793 printf("freef %p, freeb %p, mount %p\n", 794 TAILQ_NEXT(vp, v_freelist), vp->v_freelist.tqe_prev, 795 vp->v_mount); 796 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 797 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 798 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 799 vp->v_bufobj.bo_numoutput, vp->v_type); 800 VI_UNLOCK(vp); 801 } 802 #endif 803 DROP_GIANT(); 804 g_topology_lock(); 805 g_vfs_close(pmp->pm_cp, td); 806 g_topology_unlock(); 807 PICKUP_GIANT(); 808 vrele(pmp->pm_devvp); 809 free(pmp->pm_inusemap, M_MSDOSFSFAT); 810 if (pmp->pm_flags & MSDOSFS_LARGEFS) { 811 msdosfs_fileno_free(mp); 812 } 813 free(pmp, M_MSDOSFSMNT); 814 mp->mnt_data = (qaddr_t)0; 815 MNT_ILOCK(mp); 816 mp->mnt_flag &= ~MNT_LOCAL; 817 MNT_IUNLOCK(mp); 818 return (error); 819 } 820 821 static int 822 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp, struct thread *td) 823 { 824 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 825 struct denode *ndep; 826 int error; 827 828 #ifdef MSDOSFS_DEBUG 829 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 830 #endif 831 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 832 if (error) 833 return (error); 834 *vpp = DETOV(ndep); 835 return (0); 836 } 837 838 static int 839 msdosfs_statfs(struct mount *mp, struct statfs *sbp, struct thread *td) 840 { 841 struct msdosfsmount *pmp; 842 843 pmp = VFSTOMSDOSFS(mp); 844 sbp->f_bsize = pmp->pm_bpcluster; 845 sbp->f_iosize = pmp->pm_bpcluster; 846 sbp->f_blocks = pmp->pm_maxcluster + 1; 847 sbp->f_bfree = pmp->pm_freeclustercount; 848 sbp->f_bavail = pmp->pm_freeclustercount; 849 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 850 sbp->f_ffree = 0; /* what to put in here? */ 851 return (0); 852 } 853 854 static int 855 msdosfs_sync(struct mount *mp, int waitfor, struct thread *td) 856 { 857 struct vnode *vp, *nvp; 858 struct denode *dep; 859 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 860 int error, allerror = 0; 861 862 /* 863 * If we ever switch to not updating all of the fats all the time, 864 * this would be the place to update them from the first one. 865 */ 866 if (pmp->pm_fmod != 0) { 867 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 868 panic("msdosfs_sync: rofs mod"); 869 else { 870 /* update fats here */ 871 } 872 } 873 /* 874 * Write back each (modified) denode. 875 */ 876 MNT_ILOCK(mp); 877 loop: 878 MNT_VNODE_FOREACH(vp, mp, nvp) { 879 VI_LOCK(vp); 880 if (vp->v_type == VNON || (vp->v_iflag & VI_DOOMED)) { 881 VI_UNLOCK(vp); 882 continue; 883 } 884 MNT_IUNLOCK(mp); 885 dep = VTODE(vp); 886 if ((dep->de_flag & 887 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 888 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 889 waitfor == MNT_LAZY)) { 890 VI_UNLOCK(vp); 891 MNT_ILOCK(mp); 892 continue; 893 } 894 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 895 if (error) { 896 MNT_ILOCK(mp); 897 if (error == ENOENT) 898 goto loop; 899 continue; 900 } 901 error = VOP_FSYNC(vp, waitfor, td); 902 if (error) 903 allerror = error; 904 VOP_UNLOCK(vp, 0, td); 905 vrele(vp); 906 MNT_ILOCK(mp); 907 } 908 MNT_IUNLOCK(mp); 909 910 /* 911 * Flush filesystem control info. 912 */ 913 if (waitfor != MNT_LAZY) { 914 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY, td); 915 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 916 if (error) 917 allerror = error; 918 VOP_UNLOCK(pmp->pm_devvp, 0, td); 919 } 920 return (allerror); 921 } 922 923 static int 924 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, struct vnode **vpp) 925 { 926 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 927 struct defid *defhp = (struct defid *) fhp; 928 struct denode *dep; 929 int error; 930 931 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 932 if (error) { 933 *vpp = NULLVP; 934 return (error); 935 } 936 *vpp = DETOV(dep); 937 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 938 return (0); 939 } 940 941 static struct vfsops msdosfs_vfsops = { 942 .vfs_fhtovp = msdosfs_fhtovp, 943 .vfs_mount = msdosfs_mount, 944 .vfs_cmount = msdosfs_cmount, 945 .vfs_root = msdosfs_root, 946 .vfs_statfs = msdosfs_statfs, 947 .vfs_sync = msdosfs_sync, 948 .vfs_unmount = msdosfs_unmount, 949 }; 950 951 VFS_SET(msdosfs_vfsops, msdosfs, 0); 952 MODULE_VERSION(msdosfs, 1);
Cache object: 222e3597bd1dadd01e1fc819d2035a3a
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