msdosfs_vfsops.c revision 247685
11558Srgrimes/* $FreeBSD: stable/9/sys/fs/msdosfs/msdosfs_vfsops.c 247685 2013-03-03 07:09:25Z kib $ */ 21558Srgrimes/* $NetBSD: msdosfs_vfsops.c,v 1.51 1997/11/17 15:36:58 ws Exp $ */ 31558Srgrimes 41558Srgrimes/*- 51558Srgrimes * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. 61558Srgrimes * Copyright (C) 1994, 1995, 1997 TooLs GmbH. 71558Srgrimes * All rights reserved. 81558Srgrimes * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). 91558Srgrimes * 101558Srgrimes * Redistribution and use in source and binary forms, with or without 111558Srgrimes * modification, are permitted provided that the following conditions 121558Srgrimes * are met: 131558Srgrimes * 1. Redistributions of source code must retain the above copyright 141558Srgrimes * notice, this list of conditions and the following disclaimer. 151558Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 161558Srgrimes * notice, this list of conditions and the following disclaimer in the 171558Srgrimes * documentation and/or other materials provided with the distribution. 181558Srgrimes * 3. All advertising materials mentioning features or use of this software 191558Srgrimes * must display the following acknowledgement: 201558Srgrimes * This product includes software developed by TooLs GmbH. 211558Srgrimes * 4. The name of TooLs GmbH may not be used to endorse or promote products 221558Srgrimes * derived from this software without specific prior written permission. 231558Srgrimes * 241558Srgrimes * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 251558Srgrimes * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 261558Srgrimes * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 271558Srgrimes * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 281558Srgrimes * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 291558Srgrimes * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 301558Srgrimes * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 311558Srgrimes * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 321558Srgrimes * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 331558Srgrimes * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 341558Srgrimes */ 3538039Scharnier/*- 361558Srgrimes * Written by Paul Popelka (paulp@uts.amdahl.com) 371558Srgrimes * 381558Srgrimes * You can do anything you want with this software, just don't say you wrote 391558Srgrimes * it, and don't remove this notice. 401558Srgrimes * 4138039Scharnier * This software is provided "as is". 421558Srgrimes * 4338039Scharnier * The author supplies this software to be publicly redistributed on the 4438039Scharnier * understanding that the author is not responsible for the correct 4550476Speter * functioning of this software in any circumstances and is not liable for 461558Srgrimes * any damages caused by this software. 471558Srgrimes * 48108375Sdillon * October 1992 49108375Sdillon */ 50108375Sdillon 51108375Sdillon#include <sys/param.h> 52108375Sdillon#include <sys/systm.h> 5338039Scharnier#include <sys/buf.h> 5438039Scharnier#include <sys/conf.h> 551558Srgrimes#include <sys/fcntl.h> 561558Srgrimes#include <sys/iconv.h> 5778732Sdd#include <sys/kernel.h> 5838039Scharnier#include <sys/lock.h> 596661Sphk#include <sys/malloc.h> 60108375Sdillon#include <sys/mount.h> 611558Srgrimes#include <sys/mutex.h> 62108375Sdillon#include <sys/namei.h> 63108375Sdillon#include <sys/priv.h> 64108375Sdillon#include <sys/proc.h> 656661Sphk#include <sys/stat.h> 66108375Sdillon#include <sys/vnode.h> 67108375Sdillon 686661Sphk#include <geom/geom.h> 696661Sphk#include <geom/geom_vfs.h> 701558Srgrimes 7192806Sobrien#include <fs/msdosfs/bootsect.h> 72108375Sdillon#include <fs/msdosfs/bpb.h> 7392806Sobrien#include <fs/msdosfs/direntry.h> 741558Srgrimes#include <fs/msdosfs/denode.h> 75108375Sdillon#include <fs/msdosfs/fat.h> 761558Srgrimes#include <fs/msdosfs/msdosfsmount.h> 77108375Sdillon 78108375Sdillonstatic const char msdosfs_lock_msg[] = "fatlk"; 79108375Sdillon 80108375Sdillon/* Mount options that we support. */ 81108375Sdillonstatic const char *msdosfs_opts[] = { 82108375Sdillon "async", "noatime", "noclusterr", "noclusterw", 83108375Sdillon "export", "force", "from", "sync", 84108375Sdillon "cs_dos", "cs_local", "cs_win", "dirmask", 851558Srgrimes "gid", "kiconv", "large", "longname", 86108375Sdillon "longnames", "mask", "shortname", "shortnames", 87108375Sdillon "uid", "win95", "nowin95", 88108375Sdillon NULL 89108375Sdillon}; 90108375Sdillon 91108375Sdillon#if 1 /*def PC98*/ 92108375Sdillon/* 93108375Sdillon * XXX - The boot signature formatted by NEC PC-98 DOS looks like a 94108375Sdillon * garbage or a random value :-{ 95108375Sdillon * If you want to use that broken-signatured media, define the 961558Srgrimes * following symbol even though PC/AT. 97108375Sdillon * (ex. mount PC-98 DOS formatted FD on PC/AT) 98108375Sdillon */ 99108375Sdillon#define MSDOSFS_NOCHECKSIG 100108375Sdillon#endif 1011558Srgrimes 102108375SdillonMALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); 103108375Sdillonstatic MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); 104108375Sdillon 105108375Sdillonstruct iconv_functions *msdosfs_iconv; 106108375Sdillon 107108375Sdillonstatic int update_mp(struct mount *mp, struct thread *td); 108108375Sdillonstatic int mountmsdosfs(struct vnode *devvp, struct mount *mp); 109108375Sdillonstatic vfs_fhtovp_t msdosfs_fhtovp; 110108375Sdillonstatic vfs_mount_t msdosfs_mount; 111108375Sdillonstatic vfs_root_t msdosfs_root; 112108375Sdillonstatic vfs_statfs_t msdosfs_statfs; 113108375Sdillonstatic vfs_sync_t msdosfs_sync; 114108375Sdillonstatic vfs_unmount_t msdosfs_unmount; 115108375Sdillon 116108375Sdillon/* Maximum length of a character set name (arbitrary). */ 117108375Sdillon#define MAXCSLEN 64 118108375Sdillon 119108375Sdillonstatic int 120108375Sdillonupdate_mp(struct mount *mp, struct thread *td) 121108375Sdillon{ 122108375Sdillon struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 123108375Sdillon void *dos, *win, *local; 124108375Sdillon int error, v; 125108375Sdillon 126108375Sdillon if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { 127108375Sdillon if (msdosfs_iconv != NULL) { 1281558Srgrimes error = vfs_getopt(mp->mnt_optnew, 1291558Srgrimes "cs_win", &win, NULL); 130108375Sdillon if (!error) 1311558Srgrimes error = vfs_getopt(mp->mnt_optnew, 132108375Sdillon "cs_local", &local, NULL); 1331558Srgrimes if (!error) 1341558Srgrimes error = vfs_getopt(mp->mnt_optnew, 1351558Srgrimes "cs_dos", &dos, NULL); 136108375Sdillon if (!error) { 137108375Sdillon msdosfs_iconv->open(win, local, &pmp->pm_u2w); 138108375Sdillon msdosfs_iconv->open(local, win, &pmp->pm_w2u); 139108375Sdillon msdosfs_iconv->open(dos, local, &pmp->pm_u2d); 140108375Sdillon msdosfs_iconv->open(local, dos, &pmp->pm_d2u); 141108375Sdillon } 142108375Sdillon if (error != 0) 143111424Sdas return (error); 144108375Sdillon } else { 145108375Sdillon pmp->pm_w2u = NULL; 146108375Sdillon pmp->pm_u2w = NULL; 147108375Sdillon pmp->pm_d2u = NULL; 148108375Sdillon pmp->pm_u2d = NULL; 149108375Sdillon } 150108375Sdillon } 151108375Sdillon 152108375Sdillon if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1) 153108375Sdillon pmp->pm_gid = v; 154108375Sdillon if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1) 155108375Sdillon pmp->pm_uid = v; 1561558Srgrimes if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1) 157108375Sdillon pmp->pm_mask = v & ALLPERMS; 158107913Sdillon if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1) 159108375Sdillon pmp->pm_dirmask = v & ALLPERMS; 160108375Sdillon vfs_flagopt(mp->mnt_optnew, "shortname", 161108375Sdillon &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 1621558Srgrimes vfs_flagopt(mp->mnt_optnew, "shortnames", 163108375Sdillon &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); 164108375Sdillon vfs_flagopt(mp->mnt_optnew, "longname", 165108375Sdillon &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 166108375Sdillon vfs_flagopt(mp->mnt_optnew, "longnames", 167108375Sdillon &pmp->pm_flags, MSDOSFSMNT_LONGNAME); 168108375Sdillon vfs_flagopt(mp->mnt_optnew, "kiconv", 1691558Srgrimes &pmp->pm_flags, MSDOSFSMNT_KICONV); 1701558Srgrimes 1711558Srgrimes if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) 172108375Sdillon pmp->pm_flags |= MSDOSFSMNT_NOWIN95; 173111424Sdas else 1741558Srgrimes pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; 175108375Sdillon 1761558Srgrimes if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) 1771558Srgrimes pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; 178111424Sdas else if (!(pmp->pm_flags & 17926740Scharnier (MSDOSFSMNT_SHORTNAME | MSDOSFSMNT_LONGNAME))) { 1801558Srgrimes struct vnode *rootvp; 181111424Sdas 182111424Sdas /* 183111424Sdas * Try to divine whether to support Win'95 long filenames 184111424Sdas */ 185111424Sdas if (FAT32(pmp)) 186111424Sdas pmp->pm_flags |= MSDOSFSMNT_LONGNAME; 1871558Srgrimes else { 18826740Scharnier if ((error = 1891558Srgrimes msdosfs_root(mp, LK_EXCLUSIVE, &rootvp)) != 0) 1901558Srgrimes return error; 1911558Srgrimes pmp->pm_flags |= findwin95(VTODE(rootvp)) ? 1921558Srgrimes MSDOSFSMNT_LONGNAME : MSDOSFSMNT_SHORTNAME; 1931558Srgrimes vput(rootvp); 1941558Srgrimes } 1951558Srgrimes } 19626740Scharnier return 0; 197108375Sdillon} 1981558Srgrimes 199108375Sdillonstatic int 200108375Sdillonmsdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags) 201108375Sdillon{ 202108375Sdillon struct msdosfs_args args; 203108375Sdillon struct export_args exp; 204108375Sdillon int error; 205108375Sdillon 206108375Sdillon if (data == NULL) 207108375Sdillon return (EINVAL); 208108375Sdillon error = copyin(data, &args, sizeof args); 209108375Sdillon if (error) 210108375Sdillon return (error); 2111558Srgrimes vfs_oexport_conv(&args.export, &exp); 2121558Srgrimes 213107913Sdillon ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); 214108375Sdillon ma = mount_arg(ma, "export", &exp, sizeof(exp)); 215108375Sdillon ma = mount_argf(ma, "uid", "%d", args.uid); 216107913Sdillon ma = mount_argf(ma, "gid", "%d", args.gid); 217108375Sdillon ma = mount_argf(ma, "mask", "%d", args.mask); 218108375Sdillon ma = mount_argf(ma, "dirmask", "%d", args.dirmask); 219108425Smike 220108375Sdillon ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); 221108375Sdillon ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); 222108375Sdillon ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); 223108375Sdillon ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); 224108375Sdillon 225108375Sdillon ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); 226108375Sdillon ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); 227108375Sdillon ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); 228108375Sdillon 229108375Sdillon error = kernel_mount(ma, flags); 230108375Sdillon 231108375Sdillon return (error); 232108375Sdillon} 233108375Sdillon 234108375Sdillon/* 235108375Sdillon * mp - path - addr in user space of mount point (ie /usr or whatever) 236108375Sdillon * data - addr in user space of mount params including the name of the block 237108459Smike * special file to treat as a filesystem. 238108375Sdillon */ 239108375Sdillonstatic int 240108375Sdillonmsdosfs_mount(struct mount *mp) 241108375Sdillon{ 242108375Sdillon struct vnode *devvp; /* vnode for blk device to mount */ 243108375Sdillon struct thread *td; 244108375Sdillon /* msdosfs specific mount control block */ 245108375Sdillon struct msdosfsmount *pmp = NULL; 246108375Sdillon struct nameidata ndp; 247108375Sdillon int error, flags; 248108375Sdillon accmode_t accmode; 249108375Sdillon char *from; 250108375Sdillon 251108375Sdillon td = curthread; 252108375Sdillon if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) 253108375Sdillon return (EINVAL); 254108375Sdillon 255108375Sdillon /* 256108375Sdillon * If updating, check whether changing from read-only to 257108375Sdillon * read/write; if there is no device name, that's all we do. 258108375Sdillon */ 259108375Sdillon if (mp->mnt_flag & MNT_UPDATE) { 260108375Sdillon pmp = VFSTOMSDOSFS(mp); 261108375Sdillon if (vfs_flagopt(mp->mnt_optnew, "export", NULL, 0)) { 262108375Sdillon /* 263108375Sdillon * Forbid export requests if filesystem has 264108375Sdillon * MSDOSFS_LARGEFS flag set. 265108375Sdillon */ 266108375Sdillon if ((pmp->pm_flags & MSDOSFS_LARGEFS) != 0) { 267108375Sdillon vfs_mount_error(mp, 268108375Sdillon "MSDOSFS_LARGEFS flag set, cannot export"); 269108375Sdillon return (EOPNOTSUPP); 270108375Sdillon } 271108375Sdillon } 272108375Sdillon if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && 273108375Sdillon vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 274108375Sdillon error = VFS_SYNC(mp, MNT_WAIT); 275108375Sdillon if (error) 276108375Sdillon return (error); 277108375Sdillon flags = WRITECLOSE; 278108375Sdillon if (mp->mnt_flag & MNT_FORCE) 279108375Sdillon flags |= FORCECLOSE; 280108375Sdillon error = vflush(mp, 0, flags, td); 281108375Sdillon if (error) 282107913Sdillon return (error); 283 284 /* 285 * Now the volume is clean. Mark it so while the 286 * device is still rw. 287 */ 288 error = markvoldirty(pmp, 0); 289 if (error) { 290 (void)markvoldirty(pmp, 1); 291 return (error); 292 } 293 294 /* Downgrade the device from rw to ro. */ 295 DROP_GIANT(); 296 g_topology_lock(); 297 error = g_access(pmp->pm_cp, 0, -1, 0); 298 g_topology_unlock(); 299 PICKUP_GIANT(); 300 if (error) { 301 (void)markvoldirty(pmp, 1); 302 return (error); 303 } 304 305 /* 306 * Backing out after an error was painful in the 307 * above. Now we are committed to succeeding. 308 */ 309 pmp->pm_fmod = 0; 310 pmp->pm_flags |= MSDOSFSMNT_RONLY; 311 MNT_ILOCK(mp); 312 mp->mnt_flag |= MNT_RDONLY; 313 MNT_IUNLOCK(mp); 314 } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && 315 !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { 316 /* 317 * If upgrade to read-write by non-root, then verify 318 * that user has necessary permissions on the device. 319 */ 320 devvp = pmp->pm_devvp; 321 vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); 322 error = VOP_ACCESS(devvp, VREAD | VWRITE, 323 td->td_ucred, td); 324 if (error) 325 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 326 if (error) { 327 VOP_UNLOCK(devvp, 0); 328 return (error); 329 } 330 VOP_UNLOCK(devvp, 0); 331 DROP_GIANT(); 332 g_topology_lock(); 333 error = g_access(pmp->pm_cp, 0, 1, 0); 334 g_topology_unlock(); 335 PICKUP_GIANT(); 336 if (error) 337 return (error); 338 339 pmp->pm_fmod = 1; 340 pmp->pm_flags &= ~MSDOSFSMNT_RONLY; 341 MNT_ILOCK(mp); 342 mp->mnt_flag &= ~MNT_RDONLY; 343 MNT_IUNLOCK(mp); 344 345 /* Now that the volume is modifiable, mark it dirty. */ 346 error = markvoldirty(pmp, 1); 347 if (error) 348 return (error); 349 } 350 } 351 /* 352 * Not an update, or updating the name: look up the name 353 * and verify that it refers to a sensible disk device. 354 */ 355 if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) 356 return (EINVAL); 357 NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from, td); 358 error = namei(&ndp); 359 if (error) 360 return (error); 361 devvp = ndp.ni_vp; 362 NDFREE(&ndp, NDF_ONLY_PNBUF); 363 364 if (!vn_isdisk(devvp, &error)) { 365 vput(devvp); 366 return (error); 367 } 368 /* 369 * If mount by non-root, then verify that user has necessary 370 * permissions on the device. 371 */ 372 accmode = VREAD; 373 if ((mp->mnt_flag & MNT_RDONLY) == 0) 374 accmode |= VWRITE; 375 error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); 376 if (error) 377 error = priv_check(td, PRIV_VFS_MOUNT_PERM); 378 if (error) { 379 vput(devvp); 380 return (error); 381 } 382 if ((mp->mnt_flag & MNT_UPDATE) == 0) { 383 error = mountmsdosfs(devvp, mp); 384#ifdef MSDOSFS_DEBUG /* only needed for the printf below */ 385 pmp = VFSTOMSDOSFS(mp); 386#endif 387 } else { 388 vput(devvp); 389 if (devvp != pmp->pm_devvp) 390 return (EINVAL); /* XXX needs translation */ 391 } 392 if (error) { 393 vrele(devvp); 394 return (error); 395 } 396 397 error = update_mp(mp, td); 398 if (error) { 399 if ((mp->mnt_flag & MNT_UPDATE) == 0) 400 msdosfs_unmount(mp, MNT_FORCE); 401 return error; 402 } 403 404 if (devvp->v_type == VCHR && devvp->v_rdev != NULL) 405 devvp->v_rdev->si_mountpt = mp; 406 vfs_mountedfrom(mp, from); 407#ifdef MSDOSFS_DEBUG 408 printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); 409#endif 410 return (0); 411} 412 413static int 414mountmsdosfs(struct vnode *devvp, struct mount *mp) 415{ 416 struct msdosfsmount *pmp; 417 struct buf *bp; 418 struct cdev *dev; 419 union bootsector *bsp; 420 struct byte_bpb33 *b33; 421 struct byte_bpb50 *b50; 422 struct byte_bpb710 *b710; 423 u_int8_t SecPerClust; 424 u_long clusters; 425 int ronly, error; 426 struct g_consumer *cp; 427 struct bufobj *bo; 428 429 bp = NULL; /* This and pmp both used in error_exit. */ 430 pmp = NULL; 431 ronly = (mp->mnt_flag & MNT_RDONLY) != 0; 432 433 dev = devvp->v_rdev; 434 dev_ref(dev); 435 DROP_GIANT(); 436 g_topology_lock(); 437 error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); 438 g_topology_unlock(); 439 PICKUP_GIANT(); 440 VOP_UNLOCK(devvp, 0); 441 if (error) 442 goto error_exit; 443 444 bo = &devvp->v_bufobj; 445 446 /* 447 * Read the boot sector of the filesystem, and then check the 448 * boot signature. If not a dos boot sector then error out. 449 * 450 * NOTE: 8192 is a magic size that works for ffs. 451 */ 452 error = bread(devvp, 0, 8192, NOCRED, &bp); 453 if (error) 454 goto error_exit; 455 bp->b_flags |= B_AGE; 456 bsp = (union bootsector *)bp->b_data; 457 b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; 458 b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; 459 b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; 460 461#ifndef MSDOSFS_NOCHECKSIG 462 if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 463 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { 464 error = EINVAL; 465 goto error_exit; 466 } 467#endif 468 469 pmp = malloc(sizeof *pmp, M_MSDOSFSMNT, M_WAITOK | M_ZERO); 470 pmp->pm_mountp = mp; 471 pmp->pm_cp = cp; 472 pmp->pm_bo = bo; 473 474 lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); 475 476 /* 477 * Initialize ownerships and permissions, since nothing else will 478 * initialize them iff we are mounting root. 479 */ 480 pmp->pm_uid = UID_ROOT; 481 pmp->pm_gid = GID_WHEEL; 482 pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | 483 S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; 484 485 /* 486 * Experimental support for large MS-DOS filesystems. 487 * WARNING: This uses at least 32 bytes of kernel memory (which is not 488 * reclaimed until the FS is unmounted) for each file on disk to map 489 * between the 32-bit inode numbers used by VFS and the 64-bit 490 * pseudo-inode numbers used internally by msdosfs. This is only 491 * safe to use in certain controlled situations (e.g. read-only FS 492 * with less than 1 million files). 493 * Since the mappings do not persist across unmounts (or reboots), these 494 * filesystems are not suitable for exporting through NFS, or any other 495 * application that requires fixed inode numbers. 496 */ 497 vfs_flagopt(mp->mnt_optnew, "large", &pmp->pm_flags, MSDOSFS_LARGEFS); 498 499 /* 500 * Compute several useful quantities from the bpb in the 501 * bootsector. Copy in the dos 5 variant of the bpb then fix up 502 * the fields that are different between dos 5 and dos 3.3. 503 */ 504 SecPerClust = b50->bpbSecPerClust; 505 pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); 506 if (pmp->pm_BytesPerSec < DEV_BSIZE) { 507 error = EINVAL; 508 goto error_exit; 509 } 510 pmp->pm_ResSectors = getushort(b50->bpbResSectors); 511 pmp->pm_FATs = b50->bpbFATs; 512 pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); 513 pmp->pm_Sectors = getushort(b50->bpbSectors); 514 pmp->pm_FATsecs = getushort(b50->bpbFATsecs); 515 pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); 516 pmp->pm_Heads = getushort(b50->bpbHeads); 517 pmp->pm_Media = b50->bpbMedia; 518 519 /* calculate the ratio of sector size to DEV_BSIZE */ 520 pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; 521 522 /* 523 * We don't check pm_Heads nor pm_SecPerTrack, because 524 * these may not be set for EFI file systems. We don't 525 * use these anyway, so we're unaffected if they are 526 * invalid. 527 */ 528 if (!pmp->pm_BytesPerSec || !SecPerClust) { 529 error = EINVAL; 530 goto error_exit; 531 } 532 533 if (pmp->pm_Sectors == 0) { 534 pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); 535 pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); 536 } else { 537 pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); 538 pmp->pm_HugeSectors = pmp->pm_Sectors; 539 } 540 if (!(pmp->pm_flags & MSDOSFS_LARGEFS)) { 541 if (pmp->pm_HugeSectors > 0xffffffff / 542 (pmp->pm_BytesPerSec / sizeof(struct direntry)) + 1) { 543 /* 544 * We cannot deal currently with this size of disk 545 * due to fileid limitations (see msdosfs_getattr and 546 * msdosfs_readdir) 547 */ 548 error = EINVAL; 549 vfs_mount_error(mp, 550 "Disk too big, try '-o large' mount option"); 551 goto error_exit; 552 } 553 } 554 555 if (pmp->pm_RootDirEnts == 0) { 556 if (pmp->pm_FATsecs 557 || getushort(b710->bpbFSVers)) { 558 error = EINVAL; 559#ifdef MSDOSFS_DEBUG 560 printf("mountmsdosfs(): bad FAT32 filesystem\n"); 561#endif 562 goto error_exit; 563 } 564 pmp->pm_fatmask = FAT32_MASK; 565 pmp->pm_fatmult = 4; 566 pmp->pm_fatdiv = 1; 567 pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); 568 if (getushort(b710->bpbExtFlags) & FATMIRROR) 569 pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; 570 else 571 pmp->pm_flags |= MSDOSFS_FATMIRROR; 572 } else 573 pmp->pm_flags |= MSDOSFS_FATMIRROR; 574 575 /* 576 * Check a few values (could do some more): 577 * - logical sector size: power of 2, >= block size 578 * - sectors per cluster: power of 2, >= 1 579 * - number of sectors: >= 1, <= size of partition 580 * - number of FAT sectors: >= 1 581 */ 582 if ( (SecPerClust == 0) 583 || (SecPerClust & (SecPerClust - 1)) 584 || (pmp->pm_BytesPerSec < DEV_BSIZE) 585 || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) 586 || (pmp->pm_HugeSectors == 0) 587 || (pmp->pm_FATsecs == 0) 588 || (SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) 589 ) { 590 error = EINVAL; 591 goto error_exit; 592 } 593 594 pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; 595 pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ 596 pmp->pm_FATsecs *= pmp->pm_BlkPerSec; 597 SecPerClust *= pmp->pm_BlkPerSec; 598 599 pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; 600 601 if (FAT32(pmp)) { 602 pmp->pm_rootdirblk = getulong(b710->bpbRootClust); 603 pmp->pm_firstcluster = pmp->pm_fatblk 604 + (pmp->pm_FATs * pmp->pm_FATsecs); 605 pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; 606 } else { 607 pmp->pm_rootdirblk = pmp->pm_fatblk + 608 (pmp->pm_FATs * pmp->pm_FATsecs); 609 pmp->pm_rootdirsize = (pmp->pm_RootDirEnts * sizeof(struct direntry) 610 + DEV_BSIZE - 1) 611 / DEV_BSIZE; /* in blocks */ 612 pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; 613 } 614 615 pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / 616 SecPerClust + 1; 617 pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; /* XXX not used? */ 618 619 if (pmp->pm_fatmask == 0) { 620 if (pmp->pm_maxcluster 621 <= ((CLUST_RSRVD - CLUST_FIRST) & FAT12_MASK)) { 622 /* 623 * This will usually be a floppy disk. This size makes 624 * sure that one fat entry will not be split across 625 * multiple blocks. 626 */ 627 pmp->pm_fatmask = FAT12_MASK; 628 pmp->pm_fatmult = 3; 629 pmp->pm_fatdiv = 2; 630 } else { 631 pmp->pm_fatmask = FAT16_MASK; 632 pmp->pm_fatmult = 2; 633 pmp->pm_fatdiv = 1; 634 } 635 } 636 637 clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv; 638 if (pmp->pm_maxcluster >= clusters) { 639#ifdef MSDOSFS_DEBUG 640 printf("Warning: number of clusters (%ld) exceeds FAT " 641 "capacity (%ld)\n", pmp->pm_maxcluster + 1, clusters); 642#endif 643 pmp->pm_maxcluster = clusters - 1; 644 } 645 646 if (FAT12(pmp)) 647 pmp->pm_fatblocksize = 3 * 512; 648 else 649 pmp->pm_fatblocksize = PAGE_SIZE; 650 pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, 651 pmp->pm_BytesPerSec); 652 pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; 653 pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; 654 655 /* 656 * Compute mask and shift value for isolating cluster relative byte 657 * offsets and cluster numbers from a file offset. 658 */ 659 pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; 660 pmp->pm_crbomask = pmp->pm_bpcluster - 1; 661 pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; 662 663 /* 664 * Check for valid cluster size 665 * must be a power of 2 666 */ 667 if (pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) { 668 error = EINVAL; 669 goto error_exit; 670 } 671 672 /* 673 * Release the bootsector buffer. 674 */ 675 brelse(bp); 676 bp = NULL; 677 678 /* 679 * Check the fsinfo sector if we have one. Silently fix up our 680 * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) 681 * or too large. Ignore fp->fsinfree for now, since we need to 682 * read the entire FAT anyway to fill the inuse map. 683 */ 684 if (pmp->pm_fsinfo) { 685 struct fsinfo *fp; 686 687 if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 688 NOCRED, &bp)) != 0) 689 goto error_exit; 690 fp = (struct fsinfo *)bp->b_data; 691 if (!bcmp(fp->fsisig1, "RRaA", 4) 692 && !bcmp(fp->fsisig2, "rrAa", 4) 693 && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { 694 pmp->pm_nxtfree = getulong(fp->fsinxtfree); 695 if (pmp->pm_nxtfree > pmp->pm_maxcluster) 696 pmp->pm_nxtfree = CLUST_FIRST; 697 } else 698 pmp->pm_fsinfo = 0; 699 brelse(bp); 700 bp = NULL; 701 } 702 703 /* 704 * Finish initializing pmp->pm_nxtfree (just in case the first few 705 * sectors aren't properly reserved in the FAT). This completes 706 * the fixup for fp->fsinxtfree, and fixes up the zero-initialized 707 * value if there is no fsinfo. We will use pmp->pm_nxtfree 708 * internally even if there is no fsinfo. 709 */ 710 if (pmp->pm_nxtfree < CLUST_FIRST) 711 pmp->pm_nxtfree = CLUST_FIRST; 712 713 /* 714 * Allocate memory for the bitmap of allocated clusters, and then 715 * fill it in. 716 */ 717 pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) 718 * sizeof(*pmp->pm_inusemap), 719 M_MSDOSFSFAT, M_WAITOK); 720 721 /* 722 * fillinusemap() needs pm_devvp. 723 */ 724 pmp->pm_devvp = devvp; 725 pmp->pm_dev = dev; 726 727 /* 728 * Have the inuse map filled in. 729 */ 730 MSDOSFS_LOCK_MP(pmp); 731 error = fillinusemap(pmp); 732 MSDOSFS_UNLOCK_MP(pmp); 733 if (error != 0) 734 goto error_exit; 735 736 /* 737 * If they want fat updates to be synchronous then let them suffer 738 * the performance degradation in exchange for the on disk copy of 739 * the fat being correct just about all the time. I suppose this 740 * would be a good thing to turn on if the kernel is still flakey. 741 */ 742 if (mp->mnt_flag & MNT_SYNCHRONOUS) 743 pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; 744 745 /* 746 * Finish up. 747 */ 748 if (ronly) 749 pmp->pm_flags |= MSDOSFSMNT_RONLY; 750 else { 751 if ((error = markvoldirty(pmp, 1)) != 0) { 752 (void)markvoldirty(pmp, 0); 753 goto error_exit; 754 } 755 pmp->pm_fmod = 1; 756 } 757 mp->mnt_data = pmp; 758 mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); 759 mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; 760 MNT_ILOCK(mp); 761 mp->mnt_flag |= MNT_LOCAL; 762 mp->mnt_kern_flag |= MNTK_MPSAFE; 763 MNT_IUNLOCK(mp); 764 765 if (pmp->pm_flags & MSDOSFS_LARGEFS) 766 msdosfs_fileno_init(mp); 767 768 return 0; 769 770error_exit: 771 if (bp) 772 brelse(bp); 773 if (cp != NULL) { 774 DROP_GIANT(); 775 g_topology_lock(); 776 g_vfs_close(cp); 777 g_topology_unlock(); 778 PICKUP_GIANT(); 779 } 780 if (pmp) { 781 lockdestroy(&pmp->pm_fatlock); 782 if (pmp->pm_inusemap) 783 free(pmp->pm_inusemap, M_MSDOSFSFAT); 784 free(pmp, M_MSDOSFSMNT); 785 mp->mnt_data = NULL; 786 } 787 dev_rel(dev); 788 return (error); 789} 790 791/* 792 * Unmount the filesystem described by mp. 793 */ 794static int 795msdosfs_unmount(struct mount *mp, int mntflags) 796{ 797 struct msdosfsmount *pmp; 798 int error, flags; 799 800 flags = 0; 801 if (mntflags & MNT_FORCE) 802 flags |= FORCECLOSE; 803 error = vflush(mp, 0, flags, curthread); 804 if (error && error != ENXIO) 805 return error; 806 pmp = VFSTOMSDOSFS(mp); 807 if ((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0) { 808 error = markvoldirty(pmp, 0); 809 if (error && error != ENXIO) { 810 (void)markvoldirty(pmp, 1); 811 return (error); 812 } 813 } 814 if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { 815 if (pmp->pm_w2u) 816 msdosfs_iconv->close(pmp->pm_w2u); 817 if (pmp->pm_u2w) 818 msdosfs_iconv->close(pmp->pm_u2w); 819 if (pmp->pm_d2u) 820 msdosfs_iconv->close(pmp->pm_d2u); 821 if (pmp->pm_u2d) 822 msdosfs_iconv->close(pmp->pm_u2d); 823 } 824 825#ifdef MSDOSFS_DEBUG 826 { 827 struct vnode *vp = pmp->pm_devvp; 828 struct bufobj *bo; 829 830 bo = &vp->v_bufobj; 831 BO_LOCK(bo); 832 VI_LOCK(vp); 833 vn_printf(vp, 834 "msdosfs_umount(): just before calling VOP_CLOSE()\n"); 835 printf("freef %p, freeb %p, mount %p\n", 836 TAILQ_NEXT(vp, v_actfreelist), vp->v_actfreelist.tqe_prev, 837 vp->v_mount); 838 printf("cleanblkhd %p, dirtyblkhd %p, numoutput %ld, type %d\n", 839 TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), 840 TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), 841 vp->v_bufobj.bo_numoutput, vp->v_type); 842 VI_UNLOCK(vp); 843 BO_UNLOCK(bo); 844 } 845#endif 846 DROP_GIANT(); 847 if (pmp->pm_devvp->v_type == VCHR && pmp->pm_devvp->v_rdev != NULL) 848 pmp->pm_devvp->v_rdev->si_mountpt = NULL; 849 g_topology_lock(); 850 g_vfs_close(pmp->pm_cp); 851 g_topology_unlock(); 852 PICKUP_GIANT(); 853 vrele(pmp->pm_devvp); 854 dev_rel(pmp->pm_dev); 855 free(pmp->pm_inusemap, M_MSDOSFSFAT); 856 if (pmp->pm_flags & MSDOSFS_LARGEFS) 857 msdosfs_fileno_free(mp); 858 lockdestroy(&pmp->pm_fatlock); 859 free(pmp, M_MSDOSFSMNT); 860 mp->mnt_data = NULL; 861 MNT_ILOCK(mp); 862 mp->mnt_flag &= ~MNT_LOCAL; 863 MNT_IUNLOCK(mp); 864 return (error); 865} 866 867static int 868msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) 869{ 870 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 871 struct denode *ndep; 872 int error; 873 874#ifdef MSDOSFS_DEBUG 875 printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); 876#endif 877 error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, &ndep); 878 if (error) 879 return (error); 880 *vpp = DETOV(ndep); 881 return (0); 882} 883 884static int 885msdosfs_statfs(struct mount *mp, struct statfs *sbp) 886{ 887 struct msdosfsmount *pmp; 888 889 pmp = VFSTOMSDOSFS(mp); 890 sbp->f_bsize = pmp->pm_bpcluster; 891 sbp->f_iosize = pmp->pm_bpcluster; 892 sbp->f_blocks = pmp->pm_maxcluster + 1; 893 sbp->f_bfree = pmp->pm_freeclustercount; 894 sbp->f_bavail = pmp->pm_freeclustercount; 895 sbp->f_files = pmp->pm_RootDirEnts; /* XXX */ 896 sbp->f_ffree = 0; /* what to put in here? */ 897 return (0); 898} 899 900/* 901 * If we have an FSInfo block, update it. 902 */ 903static int 904msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) 905{ 906 struct fsinfo *fp; 907 struct buf *bp; 908 int error; 909 910 MSDOSFS_LOCK_MP(pmp); 911 if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { 912 error = 0; 913 goto unlock; 914 } 915 error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, 916 NOCRED, &bp); 917 if (error != 0) { 918 brelse(bp); 919 goto unlock; 920 } 921 fp = (struct fsinfo *)bp->b_data; 922 putulong(fp->fsinfree, pmp->pm_freeclustercount); 923 putulong(fp->fsinxtfree, pmp->pm_nxtfree); 924 pmp->pm_flags &= ~MSDOSFS_FSIMOD; 925 if (waitfor == MNT_WAIT) 926 error = bwrite(bp); 927 else 928 bawrite(bp); 929unlock: 930 MSDOSFS_UNLOCK_MP(pmp); 931 return (error); 932} 933 934static int 935msdosfs_sync(struct mount *mp, int waitfor) 936{ 937 struct vnode *vp, *nvp; 938 struct thread *td; 939 struct denode *dep; 940 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 941 int error, allerror = 0; 942 943 td = curthread; 944 945 /* 946 * If we ever switch to not updating all of the fats all the time, 947 * this would be the place to update them from the first one. 948 */ 949 if (pmp->pm_fmod != 0) { 950 if (pmp->pm_flags & MSDOSFSMNT_RONLY) 951 panic("msdosfs_sync: rofs mod"); 952 else { 953 /* update fats here */ 954 } 955 } 956 /* 957 * Write back each (modified) denode. 958 */ 959loop: 960 MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { 961 if (vp->v_type == VNON) { 962 VI_UNLOCK(vp); 963 continue; 964 } 965 dep = VTODE(vp); 966 if ((dep->de_flag & 967 (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && 968 (vp->v_bufobj.bo_dirty.bv_cnt == 0 || 969 waitfor == MNT_LAZY)) { 970 VI_UNLOCK(vp); 971 continue; 972 } 973 error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK, td); 974 if (error) { 975 if (error == ENOENT) 976 goto loop; 977 continue; 978 } 979 error = VOP_FSYNC(vp, waitfor, td); 980 if (error) 981 allerror = error; 982 VOP_UNLOCK(vp, 0); 983 vrele(vp); 984 } 985 986 /* 987 * Flush filesystem control info. 988 */ 989 if (waitfor != MNT_LAZY) { 990 vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); 991 error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); 992 if (error) 993 allerror = error; 994 VOP_UNLOCK(pmp->pm_devvp, 0); 995 } 996 997 error = msdosfs_fsiflush(pmp, waitfor); 998 if (error != 0) 999 allerror = error; 1000 return (allerror); 1001} 1002 1003static int 1004msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) 1005{ 1006 struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); 1007 struct defid *defhp = (struct defid *) fhp; 1008 struct denode *dep; 1009 int error; 1010 1011 error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, &dep); 1012 if (error) { 1013 *vpp = NULLVP; 1014 return (error); 1015 } 1016 *vpp = DETOV(dep); 1017 vnode_create_vobject(*vpp, dep->de_FileSize, curthread); 1018 return (0); 1019} 1020 1021static struct vfsops msdosfs_vfsops = { 1022 .vfs_fhtovp = msdosfs_fhtovp, 1023 .vfs_mount = msdosfs_mount, 1024 .vfs_cmount = msdosfs_cmount, 1025 .vfs_root = msdosfs_root, 1026 .vfs_statfs = msdosfs_statfs, 1027 .vfs_sync = msdosfs_sync, 1028 .vfs_unmount = msdosfs_unmount, 1029}; 1030 1031VFS_SET(msdosfs_vfsops, msdosfs, 0); 1032MODULE_VERSION(msdosfs, 1); 1033