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sys/fs/msdosfs/msdosfs_vfsops.c
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1 /* $FreeBSD: releng/12.0/sys/fs/msdosfs/msdosfs_vfsops.c 336966 2018-07-31 12:44:28Z emaste $ */ 2 /* $NetBSD: msdosfs_vfsops.c,v 1.51 1997/11/17 15:36:58 ws Exp $ */ 3 4 /*- 5 * SPDX-License-Identifier: BSD-4-Clause 6 * 7 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. 8 * Copyright (C) 1994, 1995, 1997 TooLs GmbH. 9 * All rights reserved. 10 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by TooLs GmbH. 23 * 4. The name of TooLs GmbH may not be used to endorse or promote products 24 * derived from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 29 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 31 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 32 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 33 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 34 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 35 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 36 */ 37 /*- 38 * Written by Paul Popelka (paulp@uts.amdahl.com) 39 * 40 * You can do anything you want with this software, just don't say you wrote 41 * it, and don't remove this notice. 42 * 43 * This software is provided "as is". 44 * 45 * The author supplies this software to be publicly redistributed on the 46 * understanding that the author is not responsible for the correct 47 * functioning of this software in any circumstances and is not liable for 48 * any damages caused by this software. 49 * 50 * October 1992 51 */ 52 53 #include <sys/param.h> 54 #include <sys/systm.h> 55 #include <sys/buf.h> 56 #include <sys/conf.h> 57 #include <sys/fcntl.h> 58 #include <sys/iconv.h> 59 #include <sys/kernel.h> 60 #include <sys/lock.h> 61 #include <sys/malloc.h> 62 #include <sys/mount.h> 63 #include <sys/mutex.h> 64 #include <sys/namei.h> 65 #include <sys/priv.h> 66 #include <sys/proc.h> 67 #include <sys/stat.h> 68 #include <sys/vnode.h> 69 70 #include <geom/geom.h> 71 #include <geom/geom_vfs.h> 72 73 #include <fs/msdosfs/bootsect.h> 74 #include <fs/msdosfs/bpb.h> 75 #include <fs/msdosfs/direntry.h> 76 #include <fs/msdosfs/denode.h> 77 #include <fs/msdosfs/fat.h> 78 #include <fs/msdosfs/msdosfsmount.h> 79 80 #ifdef MSDOSFS_DEBUG 81 #include <sys/rwlock.h> 82 #endif 83 84 static const char msdosfs_lock_msg[] = "fatlk"; 85 86 /* Mount options that we support. */ 87 static const char *msdosfs_opts[] = { 88 "async", "noatime", "noclusterr", "noclusterw", 89 "export", "force", "from", "sync", 90 "cs_dos", "cs_local", "cs_win", "dirmask", 91 "gid", "kiconv", "longname", 92 "longnames", "mask", "shortname", "shortnames", 93 "uid", "win95", "nowin95", 94 NULL 95 }; 96 97 #if 1 /*def PC98*/ 98 /* 99 * XXX - The boot signature formatted by NEC PC-98 DOS looks like a 100 * garbage or a random value :-{ 101 * If you want to use that broken-signatured media, define the 102 * following symbol even though PC/AT. 103 * (ex. mount PC-98 DOS formatted FD on PC/AT) 104 */ 105 #define MSDOSFS_NOCHECKSIG 106 #endif 107 108 MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); 109 static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); 110 111 struct iconv_functions *msdosfs_iconv; 112 113 static int update_mp(struct mount *mp, struct thread *td); 114 static int mountmsdosfs(struct vnode *devvp, struct mount *mp); 115 static vfs_fhtovp_t msdosfs_fhtovp; 116 static vfs_mount_t msdosfs_mount; 117 static vfs_root_t msdosfs_root; 118 static vfs_statfs_t msdosfs_statfs; 119 static vfs_sync_t msdosfs_sync; 120 static vfs_unmount_t msdosfs_unmount; 121 122 /* Maximum length of a character set name (arbitrary). */ 123 #define MAXCSLEN 64 124 125 static int 126 update_mp(struct mount *mp, struct thread *td) 127 { 128 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 129 void *dos, *win, *local; 130 int error, v; 131 132 if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { 133 if (msdosfs_iconv != NULL) { 134 error = vfs_getopt(mp->mnt_optnew, 135 "cs_win", &win, NULL); 136 if (!error) 137 error = vfs_getopt(mp->mnt_optnew, 138 "cs_local", &local, NULL); 139 if (!error) 140 error = vfs_getopt(mp->mnt_optnew, 141 "cs_dos", &dos, NULL); 142 if (!error) { 143 msdosfs_iconv->open(win, local, &pmp->pm_u2w); 144 msdosfs_iconv->open(local, win, &pmp->pm_w2u); 145 msdosfs_iconv->open(dos, local, &pmp->pm_u2d); 146 msdosfs_iconv->open(local, dos, &pmp->pm_d2u); 147 } 148 if (error != 0) 149 return (error); 150 } else { 151 pmp->pm_w2u = NULL; 152 pmp->pm_u2w = NULL; 153 pmp->pm_d2u = NULL; 154 pmp->pm_u2d = NULL; 155 } 156 } 157 158 if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1) 159 pmp->pm_gid = v; 160 if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1) 161 pmp->pm_uid = v; 162 if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1) 163 pmp->pm_mask = v & ALLPERMS; 164 if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1) 165 pmp->pm_dirmask = v & ALLPERMS; 166 vfs_flagopt(mp->mnt_optnew, "shortname", 167 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 168 vfs_flagopt(mp->mnt_optnew, "shortnames", 169 &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 170 vfs_flagopt(mp->mnt_optnew, "longname", 171 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 172 vfs_flagopt(mp->mnt_optnew, "longnames", 173 &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 174 vfs_flagopt(mp->mnt_optnew, "kiconv", 175 &pmp->pm_flags, MSDOSFSMNT_KICONV); 176 177 if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) 178 pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 179 else 180 pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; 181 182 if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 183 pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 184 else 185 pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 186 return 0; 187 } 188 189 static int 190 msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags) 191 { 192 struct msdosfs_args args; 193 struct export_args exp; 194 int error; 195 196 if (data == NULL) 197 return (EINVAL); 198 error = copyin(data, &args, sizeof args); 199 if (error) 200 return (error); 201 vfs_oexport_conv(&args.export, &exp); 202 203 ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 204 ma = mount_arg(ma, "export", &exp, sizeof(exp)); 205 ma = mount_argf(ma, "uid", "%d", args.uid); 206 ma = mount_argf(ma, "gid", "%d", args.gid); 207 ma = mount_argf(ma, "mask", "%d", args.mask); 208 ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 209 210 ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 211 ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 212 ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 213 ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 214 215 ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 216 ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 217 ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 218 219 error = kernel_mount(ma, flags); 220 221 return (error); 222 } 223 224 /* 225 * mp - path - addr in user space of mount point (ie /usr or whatever) 226 * data - addr in user space of mount params including the name of the block 227 * special file to treat as a filesystem. 228 */ 229 static int 230 msdosfs_mount(struct mount *mp) 231 { 232 struct vnode *devvp; /* vnode for blk device to mount */ 233 struct thread *td; 234 /* msdosfs specific mount control block */ 235 struct msdosfsmount *pmp = NULL; 236 struct nameidata ndp; 237 int error, flags; 238 accmode_t accmode; 239 char *from; 240 241 td = curthread; 242 if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 243 return (EINVAL); 244 245 /* 246 * If updating, check whether changing from read-only to 247 * read/write; if there is no device name, that's all we do. 248 */ 249 if (mp->mnt_flag & MNT_UPDATE) { 250 pmp = VFSTOMSDOSFS(mp); 251 if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 252 vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 253 error = VFS_SYNC(mp, MNT_WAIT); 254 if (error) 255 return (error); 256 flags = WRITECLOSE; 257 if (mp->mnt_flag & MNT_FORCE) 258 flags |= FORCECLOSE; 259 error = vflush(mp, 0, flags, td); 260 if (error) 261 return (error); 262 263 /* 264 * Now the volume is clean. Mark it so while the 265 * device is still rw. 266 */ 267 error = markvoldirty(pmp, 0); 268 if (error) { 269 (void)markvoldirty(pmp, 1); 270 return (error); 271 } 272 273 /* Downgrade the device from rw to ro. */ 274 g_topology_lock(); 275 error = g_access(pmp->pm_cp, 0, -1, 0); 276 g_topology_unlock(); 277 if (error) { 278 (void)markvoldirty(pmp, 1); 279 return (error); 280 } 281 282 /* 283 * Backing out after an error was painful in the 284 * above. Now we are committed to succeeding. 285 */ 286 pmp->pm_fmod = 0; 287 pmp->pm_flags |= MSDOSFSMNT_RONLY; 288 MNT_ILOCK(mp); 289 mp->mnt_flag |= MNT_RDONLY; 290 MNT_IUNLOCK(mp); 291 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 292 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 293 /* 294 * If upgrade to read-write by non-root, then verify 295 * that user has necessary permissions on the device. 296 */ 297 devvp = pmp->pm_devvp; 298 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 299 error = VOP_ACCESS(devvp, VREAD | VWRITE, 300 td->td_ucred, td); 301 if (error) 302 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 303 if (error) { 304 VOP_UNLOCK(devvp, 0); 305 return (error); 306 } 307 VOP_UNLOCK(devvp, 0); 308 g_topology_lock(); 309 error = g_access(pmp->pm_cp, 0, 1, 0); 310 g_topology_unlock(); 311 if (error) 312 return (error); 313 314 pmp->pm_fmod = 1; 315 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 316 MNT_ILOCK(mp); 317 mp->mnt_flag &= ~MNT_RDONLY; 318 MNT_IUNLOCK(mp); 319 320 /* Now that the volume is modifiable, mark it dirty. */ 321 error = markvoldirty(pmp, 1); 322 if (error) 323 return (error); 324 } 325 } 326 /* 327 * Not an update, or updating the name: look up the name 328 * and verify that it refers to a sensible disk device. 329 */ 330 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 331 return (EINVAL); 332 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 333 error = namei(&ndp); 334 if (error) 335 return (error); 336 devvp = ndp.ni_vp; 337 NDFREE(&ndp, NDF_ONLY_PNBUF); 338 339 if (!vn_isdisk(devvp, &error)) { 340 vput(devvp); 341 return (error); 342 } 343 /* 344 * If mount by non-root, then verify that user has necessary 345 * permissions on the device. 346 */ 347 accmode = VREAD; 348 if ((mp->mnt_flag & MNT_RDONLY) == 0) 349 accmode |= VWRITE; 350 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 351 if (error) 352 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 353 if (error) { 354 vput(devvp); 355 return (error); 356 } 357 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 358 error = mountmsdosfs(devvp, mp); 359 #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 360 pmp = VFSTOMSDOSFS(mp); 361 #endif 362 } else { 363 vput(devvp); 364 if (devvp != pmp->pm_devvp) 365 return (EINVAL); /* XXX needs translation */ 366 } 367 if (error) { 368 vrele(devvp); 369 return (error); 370 } 371 372 error = update_mp(mp, td); 373 if (error) { 374 if ((mp->mnt_flag & MNT_UPDATE) == 0) 375 msdosfs_unmount(mp, MNT_FORCE); 376 return error; 377 } 378 379 vfs_mountedfrom(mp, from); 380 #ifdef MSDOSFS_DEBUG 381 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 382 #endif 383 return (0); 384 } 385 386 static int 387 mountmsdosfs(struct vnode *devvp, struct mount *mp) 388 { 389 struct msdosfsmount *pmp; 390 struct buf *bp; 391 struct cdev *dev; 392 union bootsector *bsp; 393 struct byte_bpb33 *b33; 394 struct byte_bpb50 *b50; 395 struct byte_bpb710 *b710; 396 uint8_t SecPerClust; 397 u_long clusters; 398 int ronly, error; 399 struct g_consumer *cp; 400 struct bufobj *bo; 401 402 bp = NULL; /* This and pmp both used in error_exit. */ 403 pmp = NULL; 404 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 405 406 dev = devvp->v_rdev; 407 if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0, 408 (uintptr_t)mp) == 0) { 409 VOP_UNLOCK(devvp, 0); 410 return (EBUSY); 411 } 412 g_topology_lock(); 413 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 414 g_topology_unlock(); 415 if (error != 0) { 416 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 417 VOP_UNLOCK(devvp, 0); 418 return (error); 419 } 420 dev_ref(dev); 421 VOP_UNLOCK(devvp, 0); 422 423 bo = &devvp->v_bufobj; 424 425 /* 426 * Read the boot sector of the filesystem, and then check the 427 * boot signature. If not a dos boot sector then error out. 428 * 429 * NOTE: 8192 is a magic size that works for ffs. 430 */ 431 error = bread(devvp, 0, 8192, NOCRED, &bp); 432 if (error) 433 goto error_exit; 434 bp->b_flags |= B_AGE; 435 bsp = (union bootsector *)bp->b_data; 436 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 437 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 438 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 439 440 #ifndef MSDOSFS_NOCHECKSIG 441 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 442 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 443 error = EINVAL; 444 goto error_exit; 445 } 446 #endif 447 448 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 449 pmp->pm_mountp = mp; 450 pmp->pm_cp = cp; 451 pmp->pm_bo = bo; 452 453 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); 454 455 /* 456 * Initialize ownerships and permissions, since nothing else will 457 * initialize them iff we are mounting root. 458 */ 459 pmp->pm_uid = UID_ROOT; 460 pmp->pm_gid = GID_WHEEL; 461 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 462 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 463 464 /* 465 * Compute several useful quantities from the bpb in the 466 * bootsector. Copy in the dos 5 variant of the bpb then fix up 467 * the fields that are different between dos 5 and dos 3.3. 468 */ 469 SecPerClust = b50->bpbSecPerClust; 470 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 471 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 472 error = EINVAL; 473 goto error_exit; 474 } 475 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 476 pmp->pm_FATs = b50->bpbFATs; 477 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 478 pmp->pm_Sectors = getushort(b50->bpbSectors); 479 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 480 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 481 pmp->pm_Heads = getushort(b50->bpbHeads); 482 pmp->pm_Media = b50->bpbMedia; 483 484 /* calculate the ratio of sector size to DEV_BSIZE */ 485 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 486 487 /* 488 * We don't check pm_Heads nor pm_SecPerTrack, because 489 * these may not be set for EFI file systems. We don't 490 * use these anyway, so we're unaffected if they are 491 * invalid. 492 */ 493 if (!pmp->pm_BytesPerSec || !SecPerClust) { 494 error = EINVAL; 495 goto error_exit; 496 } 497 498 if (pmp->pm_Sectors == 0) { 499 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 500 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 501 } else { 502 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 503 pmp->pm_HugeSectors = pmp->pm_Sectors; 504 } 505 506 if (pmp->pm_RootDirEnts == 0) { 507 if (pmp->pm_FATsecs 508 || getushort(b710->bpbFSVers)) { 509 error = EINVAL; 510 #ifdef MSDOSFS_DEBUG 511 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 512 #endif 513 goto error_exit; 514 } 515 pmp->pm_fatmask = FAT32_MASK; 516 pmp->pm_fatmult = 4; 517 pmp->pm_fatdiv = 1; 518 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 519 if (getushort(b710->bpbExtFlags) & FATMIRROR) 520 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 521 else 522 pmp->pm_flags |= MSDOSFS_FATMIRROR; 523 } else 524 pmp->pm_flags |= MSDOSFS_FATMIRROR; 525 526 /* 527 * Check a few values (could do some more): 528 * - logical sector size: power of 2, >= block size 529 * - sectors per cluster: power of 2, >= 1 530 * - number of sectors: >= 1, <= size of partition 531 * - number of FAT sectors: >= 1 532 */ 533 if ( (SecPerClust == 0) 534 || (SecPerClust & (SecPerClust - 1)) 535 || (pmp->pm_BytesPerSec < DEV_BSIZE) 536 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 537 || (pmp->pm_HugeSectors == 0) 538 || (pmp->pm_FATsecs == 0) 539 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) 540 ) { 541 error = EINVAL; 542 goto error_exit; 543 } 544 545 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 546 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 547 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 548 SecPerClust *= pmp->pm_BlkPerSec; 549 550 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 551 552 if (FAT32(pmp)) { 553 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 554 pmp->pm_firstcluster = pmp->pm_fatblk 555 + (pmp->pm_FATs * pmp->pm_FATsecs); 556 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 557 } else { 558 pmp->pm_rootdirblk = pmp->pm_fatblk + 559 (pmp->pm_FATs * pmp->pm_FATsecs); 560 pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts * 561 sizeof(struct direntry), DEV_BSIZE); /* in blocks */ 562 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 563 } 564 565 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 566 SecPerClust + 1; 567 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 568 569 if (pmp->pm_fatmask == 0) { 570 if (pmp->pm_maxcluster 571 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 572 /* 573 * This will usually be a floppy disk. This size makes 574 * sure that one FAT entry will not be split across 575 * multiple blocks. 576 */ 577 pmp->pm_fatmask = FAT12_MASK; 578 pmp->pm_fatmult = 3; 579 pmp->pm_fatdiv = 2; 580 } else { 581 pmp->pm_fatmask = FAT16_MASK; 582 pmp->pm_fatmult = 2; 583 pmp->pm_fatdiv = 1; 584 } 585 } 586 587 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 588 if (pmp->pm_maxcluster >= clusters) { 589 #ifdef MSDOSFS_DEBUG 590 printf("Warning: number of clusters (%ld) exceeds FAT " 591 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 592 #endif 593 pmp->pm_maxcluster = clusters - 1; 594 } 595 596 if (FAT12(pmp)) 597 pmp->pm_fatblocksize = 3 * 512; 598 else 599 pmp->pm_fatblocksize = PAGE_SIZE; 600 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 601 pmp->pm_BytesPerSec); 602 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 603 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 604 605 /* 606 * Compute mask and shift value for isolating cluster relative byte 607 * offsets and cluster numbers from a file offset. 608 */ 609 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 610 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 611 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 612 613 /* 614 * Check for valid cluster size 615 * must be a power of 2 616 */ 617 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 618 error = EINVAL; 619 goto error_exit; 620 } 621 622 /* 623 * Release the bootsector buffer. 624 */ 625 brelse(bp); 626 bp = NULL; 627 628 /* 629 * Check the fsinfo sector if we have one. Silently fix up our 630 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 631 * or too large. Ignore fp->fsinfree for now, since we need to 632 * read the entire FAT anyway to fill the inuse map. 633 */ 634 if (pmp->pm_fsinfo) { 635 struct fsinfo *fp; 636 637 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 638 NOCRED, &bp)) != 0) 639 goto error_exit; 640 fp = (struct fsinfo *)bp->b_data; 641 if (!bcmp(fp->fsisig1, "RRaA", 4) 642 && !bcmp(fp->fsisig2, "rrAa", 4) 643 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 644 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 645 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 646 pmp->pm_nxtfree = CLUST_FIRST; 647 } else 648 pmp->pm_fsinfo = 0; 649 brelse(bp); 650 bp = NULL; 651 } 652 653 /* 654 * Finish initializing pmp->pm_nxtfree (just in case the first few 655 * sectors aren't properly reserved in the FAT). This completes 656 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 657 * value if there is no fsinfo. We will use pmp->pm_nxtfree 658 * internally even if there is no fsinfo. 659 */ 660 if (pmp->pm_nxtfree < CLUST_FIRST) 661 pmp->pm_nxtfree = CLUST_FIRST; 662 663 /* 664 * Allocate memory for the bitmap of allocated clusters, and then 665 * fill it in. 666 */ 667 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 668 * sizeof(*pmp->pm_inusemap), 669 M_MSDOSFSFAT, M_WAITOK); 670 671 /* 672 * fillinusemap() needs pm_devvp. 673 */ 674 pmp->pm_devvp = devvp; 675 pmp->pm_dev = dev; 676 677 /* 678 * Have the inuse map filled in. 679 */ 680 MSDOSFS_LOCK_MP(pmp); 681 error = fillinusemap(pmp); 682 MSDOSFS_UNLOCK_MP(pmp); 683 if (error != 0) 684 goto error_exit; 685 686 /* 687 * If they want FAT updates to be synchronous then let them suffer 688 * the performance degradation in exchange for the on disk copy of 689 * the FAT being correct just about all the time. I suppose this 690 * would be a good thing to turn on if the kernel is still flakey. 691 */ 692 if (mp->mnt_flag & MNT_SYNCHRONOUS) 693 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 694 695 /* 696 * Finish up. 697 */ 698 if (ronly) 699 pmp->pm_flags |= MSDOSFSMNT_RONLY; 700 else { 701 if ((error = markvoldirty(pmp, 1)) != 0) { 702 (void)markvoldirty(pmp, 0); 703 goto error_exit; 704 } 705 pmp->pm_fmod = 1; 706 } 707 mp->mnt_data = pmp; 708 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 709 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 710 MNT_ILOCK(mp); 711 mp->mnt_flag |= MNT_LOCAL; 712 mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF; 713 MNT_IUNLOCK(mp); 714 715 return (0); 716 717 error_exit: 718 if (bp) 719 brelse(bp); 720 if (cp != NULL) { 721 g_topology_lock(); 722 g_vfs_close(cp); 723 g_topology_unlock(); 724 } 725 if (pmp) { 726 lockdestroy(&pmp->pm_fatlock); 727 free(pmp->pm_inusemap, M_MSDOSFSFAT); 728 free(pmp, M_MSDOSFSMNT); 729 mp->mnt_data = NULL; 730 } 731 atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); 732 dev_rel(dev); 733 return (error); 734 } 735 736 /* 737 * Unmount the filesystem described by mp. 738 */ 739 static int 740 msdosfs_unmount(struct mount *mp, int mntflags) 741 { 742 struct msdosfsmount *pmp; 743 int error, flags; 744 745 error = flags = 0; 746 pmp = VFSTOMSDOSFS(mp); 747 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) 748 error = msdosfs_sync(mp, MNT_WAIT); 749 if ((mntflags & MNT_FORCE) != 0) 750 flags |= FORCECLOSE; 751 else if (error != 0) 752 return (error); 753 error = vflush(mp, 0, flags, curthread); 754 if (error != 0 && error != ENXIO) 755 return (error); 756 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 757 error = markvoldirty(pmp, 0); 758 if (error && error != ENXIO) { 759 (void)markvoldirty(pmp, 1); 760 return (error); 761 } 762 } 763 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 764 if (pmp->pm_w2u) 765 msdosfs_iconv->close(pmp->pm_w2u); 766 if (pmp->pm_u2w) 767 msdosfs_iconv->close(pmp->pm_u2w); 768 if (pmp->pm_d2u) 769 msdosfs_iconv->close(pmp->pm_d2u); 770 if (pmp->pm_u2d) 771 msdosfs_iconv->close(pmp->pm_u2d); 772 } 773 774 #ifdef MSDOSFS_DEBUG 775 { 776 struct vnode *vp = pmp->pm_devvp; 777 struct bufobj *bo; 778 779 bo = &vp->v_bufobj; 780 BO_LOCK(bo); 781 VI_LOCK(vp); 782 vn_printf(vp, 783 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 784 printf("freef %p, freeb %p, mount %p\n", 785 TAILQ_NEXT(vp, v_actfreelist), vp->v_actfreelist.tqe_prev, 786 vp->v_mount); 787 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 788 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 789 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 790 vp->v_bufobj.bo_numoutput, vp->v_type); 791 VI_UNLOCK(vp); 792 BO_UNLOCK(bo); 793 } 794 #endif 795 g_topology_lock(); 796 g_vfs_close(pmp->pm_cp); 797 g_topology_unlock(); 798 atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0); 799 vrele(pmp->pm_devvp); 800 dev_rel(pmp->pm_dev); 801 free(pmp->pm_inusemap, M_MSDOSFSFAT); 802 lockdestroy(&pmp->pm_fatlock); 803 free(pmp, M_MSDOSFSMNT); 804 mp->mnt_data = NULL; 805 MNT_ILOCK(mp); 806 mp->mnt_flag &= ~MNT_LOCAL; 807 MNT_IUNLOCK(mp); 808 return (error); 809 } 810 811 static int 812 msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 813 { 814 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 815 struct denode *ndep; 816 int error; 817 818 #ifdef MSDOSFS_DEBUG 819 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 820 #endif 821 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 822 if (error) 823 return (error); 824 *vpp = DETOV(ndep); 825 return (0); 826 } 827 828 static int 829 msdosfs_statfs(struct mount *mp, struct statfs *sbp) 830 { 831 struct msdosfsmount *pmp; 832 833 pmp = VFSTOMSDOSFS(mp); 834 sbp->f_bsize = pmp->pm_bpcluster; 835 sbp->f_iosize = pmp->pm_bpcluster; 836 sbp->f_blocks = pmp->pm_maxcluster + 1; 837 sbp->f_bfree = pmp->pm_freeclustercount; 838 sbp->f_bavail = pmp->pm_freeclustercount; 839 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 840 sbp->f_ffree = 0; /* what to put in here? */ 841 return (0); 842 } 843 844 /* 845 * If we have an FSInfo block, update it. 846 */ 847 static int 848 msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) 849 { 850 struct fsinfo *fp; 851 struct buf *bp; 852 int error; 853 854 MSDOSFS_LOCK_MP(pmp); 855 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { 856 error = 0; 857 goto unlock; 858 } 859 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 860 NOCRED, &bp); 861 if (error != 0) { 862 brelse(bp); 863 goto unlock; 864 } 865 fp = (struct fsinfo *)bp->b_data; 866 putulong(fp->fsinfree, pmp->pm_freeclustercount); 867 putulong(fp->fsinxtfree, pmp->pm_nxtfree); 868 pmp->pm_flags &= ~MSDOSFS_FSIMOD; 869 if (waitfor == MNT_WAIT) 870 error = bwrite(bp); 871 else 872 bawrite(bp); 873 unlock: 874 MSDOSFS_UNLOCK_MP(pmp); 875 return (error); 876 } 877 878 static int 879 msdosfs_sync(struct mount *mp, int waitfor) 880 { 881 struct vnode *vp, *nvp; 882 struct thread *td; 883 struct denode *dep; 884 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 885 int error, allerror = 0; 886 887 td = curthread; 888 889 /* 890 * If we ever switch to not updating all of the FATs all the time, 891 * this would be the place to update them from the first one. 892 */ 893 if (pmp->pm_fmod != 0) { 894 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 895 panic("msdosfs_sync: rofs mod"); 896 else { 897 /* update FATs here */ 898 } 899 } 900 /* 901 * Write back each (modified) denode. 902 */ 903 loop: 904 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { 905 if (vp->v_type == VNON) { 906 VI_UNLOCK(vp); 907 continue; 908 } 909 dep = VTODE(vp); 910 if ((dep->de_flag & 911 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 912 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 913 waitfor == MNT_LAZY)) { 914 VI_UNLOCK(vp); 915 continue; 916 } 917 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 918 if (error) { 919 if (error == ENOENT) 920 goto loop; 921 continue; 922 } 923 error = VOP_FSYNC(vp, waitfor, td); 924 if (error) 925 allerror = error; 926 VOP_UNLOCK(vp, 0); 927 vrele(vp); 928 } 929 930 /* 931 * Flush filesystem control info. 932 */ 933 if (waitfor != MNT_LAZY) { 934 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 935 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 936 if (error) 937 allerror = error; 938 VOP_UNLOCK(pmp->pm_devvp, 0); 939 } 940 941 error = msdosfs_fsiflush(pmp, waitfor); 942 if (error != 0) 943 allerror = error; 944 return (allerror); 945 } 946 947 static int 948 msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) 949 { 950 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 951 struct defid *defhp = (struct defid *) fhp; 952 struct denode *dep; 953 int error; 954 955 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 956 if (error) { 957 *vpp = NULLVP; 958 return (error); 959 } 960 *vpp = DETOV(dep); 961 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 962 return (0); 963 } 964 965 static struct vfsops msdosfs_vfsops = { 966 .vfs_fhtovp = msdosfs_fhtovp, 967 .vfs_mount = msdosfs_mount, 968 .vfs_cmount = msdosfs_cmount, 969 .vfs_root = msdosfs_root, 970 .vfs_statfs = msdosfs_statfs, 971 .vfs_sync = msdosfs_sync, 972 .vfs_unmount = msdosfs_unmount, 973 }; 974 975 VFS_SET(msdosfs_vfsops, msdosfs, 0); 976 MODULE_VERSION(msdosfs, 1);
Cache object: 6500431f297afa27be993532b22bce7a
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