/* $NetBSD: msdosfs_vfsops.c,v 1.51 1997/11/17 15:36:58 ws Exp $ */ /*- * SPDX-License-Identifier: BSD-4-Clause * * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. * Copyright (C) 1994, 1995, 1997 TooLs GmbH. * All rights reserved. * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by TooLs GmbH. * 4. The name of TooLs GmbH may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ /*- * Written by Paul Popelka (paulp@uts.amdahl.com) * * You can do anything you want with this software, just don't say you wrote * it, and don't remove this notice. * * This software is provided "as is". * * The author supplies this software to be publicly redistributed on the * understanding that the author is not responsible for the correct * functioning of this software in any circumstances and is not liable for * any damages caused by this software. * * October 1992 */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #ifdef MSDOSFS_DEBUG #include #endif static const char msdosfs_lock_msg[] = "fatlk"; /* Mount options that we support. */ static const char *msdosfs_opts[] = { "async", "noatime", "noclusterr", "noclusterw", "export", "force", "from", "sync", "cs_dos", "cs_local", "cs_win", "dirmask", "gid", "kiconv", "longname", "longnames", "mask", "shortname", "shortnames", "uid", "win95", "nowin95", NULL }; #if 1 /*def PC98*/ /* * XXX - The boot signature formatted by NEC PC-98 DOS looks like a * garbage or a random value :-{ * If you want to use that broken-signatured media, define the * following symbol even though PC/AT. * (ex. mount PC-98 DOS formatted FD on PC/AT) */ #define MSDOSFS_NOCHECKSIG #endif MALLOC_DEFINE(M_MSDOSFSMNT, "msdosfs_mount", "MSDOSFS mount structure"); static MALLOC_DEFINE(M_MSDOSFSFAT, "msdosfs_fat", "MSDOSFS file allocation table"); struct iconv_functions *msdosfs_iconv; static int update_mp(struct mount *mp, struct thread *td); static int mountmsdosfs(struct vnode *devvp, struct mount *mp); static void msdosfs_remount_ro(void *arg, int pending); static vfs_fhtovp_t msdosfs_fhtovp; static vfs_mount_t msdosfs_mount; static vfs_root_t msdosfs_root; static vfs_statfs_t msdosfs_statfs; static vfs_sync_t msdosfs_sync; static vfs_unmount_t msdosfs_unmount; /* Maximum length of a character set name (arbitrary). */ #define MAXCSLEN 64 static int update_mp(struct mount *mp, struct thread *td) { struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); void *dos, *win, *local; int error, v; if (!vfs_getopt(mp->mnt_optnew, "kiconv", NULL, NULL)) { if (msdosfs_iconv != NULL) { error = vfs_getopt(mp->mnt_optnew, "cs_win", &win, NULL); if (!error) error = vfs_getopt(mp->mnt_optnew, "cs_local", &local, NULL); if (!error) error = vfs_getopt(mp->mnt_optnew, "cs_dos", &dos, NULL); if (!error) { msdosfs_iconv->open(win, local, &pmp->pm_u2w); msdosfs_iconv->open(local, win, &pmp->pm_w2u); msdosfs_iconv->open(dos, local, &pmp->pm_u2d); msdosfs_iconv->open(local, dos, &pmp->pm_d2u); } if (error != 0) return (error); } else { pmp->pm_w2u = NULL; pmp->pm_u2w = NULL; pmp->pm_d2u = NULL; pmp->pm_u2d = NULL; } } if (vfs_scanopt(mp->mnt_optnew, "gid", "%d", &v) == 1) pmp->pm_gid = v; if (vfs_scanopt(mp->mnt_optnew, "uid", "%d", &v) == 1) pmp->pm_uid = v; if (vfs_scanopt(mp->mnt_optnew, "mask", "%d", &v) == 1) pmp->pm_mask = v & ALLPERMS; if (vfs_scanopt(mp->mnt_optnew, "dirmask", "%d", &v) == 1) pmp->pm_dirmask = v & ALLPERMS; vfs_flagopt(mp->mnt_optnew, "shortname", &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); vfs_flagopt(mp->mnt_optnew, "shortnames", &pmp->pm_flags, MSDOSFSMNT_SHORTNAME); vfs_flagopt(mp->mnt_optnew, "longname", &pmp->pm_flags, MSDOSFSMNT_LONGNAME); vfs_flagopt(mp->mnt_optnew, "longnames", &pmp->pm_flags, MSDOSFSMNT_LONGNAME); vfs_flagopt(mp->mnt_optnew, "kiconv", &pmp->pm_flags, MSDOSFSMNT_KICONV); if (vfs_getopt(mp->mnt_optnew, "nowin95", NULL, NULL) == 0) pmp->pm_flags |= MSDOSFSMNT_NOWIN95; else pmp->pm_flags &= ~MSDOSFSMNT_NOWIN95; if (pmp->pm_flags & MSDOSFSMNT_NOWIN95) pmp->pm_flags |= MSDOSFSMNT_SHORTNAME; else pmp->pm_flags |= MSDOSFSMNT_LONGNAME; return 0; } static int msdosfs_cmount(struct mntarg *ma, void *data, uint64_t flags) { struct msdosfs_args args; int error; if (data == NULL) return (EINVAL); error = copyin(data, &args, sizeof args); if (error) return (error); ma = mount_argsu(ma, "from", args.fspec, MAXPATHLEN); ma = mount_arg(ma, "export", &args.export, sizeof(args.export)); ma = mount_argf(ma, "uid", "%d", args.uid); ma = mount_argf(ma, "gid", "%d", args.gid); ma = mount_argf(ma, "mask", "%d", args.mask); ma = mount_argf(ma, "dirmask", "%d", args.dirmask); ma = mount_argb(ma, args.flags & MSDOSFSMNT_SHORTNAME, "noshortname"); ma = mount_argb(ma, args.flags & MSDOSFSMNT_LONGNAME, "nolongname"); ma = mount_argb(ma, !(args.flags & MSDOSFSMNT_NOWIN95), "nowin95"); ma = mount_argb(ma, args.flags & MSDOSFSMNT_KICONV, "nokiconv"); ma = mount_argsu(ma, "cs_win", args.cs_win, MAXCSLEN); ma = mount_argsu(ma, "cs_dos", args.cs_dos, MAXCSLEN); ma = mount_argsu(ma, "cs_local", args.cs_local, MAXCSLEN); error = kernel_mount(ma, flags); return (error); } /* * mp - path - addr in user space of mount point (ie /usr or whatever) * data - addr in user space of mount params including the name of the block * special file to treat as a filesystem. */ static int msdosfs_mount(struct mount *mp) { struct vnode *devvp, *odevvp; /* vnode for blk device to mount */ struct thread *td; /* msdosfs specific mount control block */ struct msdosfsmount *pmp = NULL; struct nameidata ndp; int error, flags; accmode_t accmode; char *from; td = curthread; if (vfs_filteropt(mp->mnt_optnew, msdosfs_opts)) return (EINVAL); /* * If updating, check whether changing from read-only to * read/write; if there is no device name, that's all we do. */ if (mp->mnt_flag & MNT_UPDATE) { pmp = VFSTOMSDOSFS(mp); if (!(pmp->pm_flags & MSDOSFSMNT_RONLY) && vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { if ((error = vn_start_write(NULL, &mp, V_WAIT)) != 0) return (error); error = vfs_write_suspend_umnt(mp); if (error != 0) return (error); flags = WRITECLOSE; if (mp->mnt_flag & MNT_FORCE) flags |= FORCECLOSE; error = vflush(mp, 0, flags, td); if (error != 0) { vfs_write_resume(mp, 0); return (error); } /* * Now the volume is clean. Mark it so while the * device is still rw. */ error = markvoldirty(pmp, 0); if (error != 0) { vfs_write_resume(mp, 0); (void)markvoldirty(pmp, 1); return (error); } /* Downgrade the device from rw to ro. */ g_topology_lock(); error = g_access(pmp->pm_cp, 0, -1, 0); g_topology_unlock(); if (error) { vfs_write_resume(mp, 0); (void)markvoldirty(pmp, 1); return (error); } /* * Backing out after an error was painful in the * above. Now we are committed to succeeding. */ pmp->pm_fmod = 0; pmp->pm_flags |= MSDOSFSMNT_RONLY; MNT_ILOCK(mp); mp->mnt_flag |= MNT_RDONLY; MNT_IUNLOCK(mp); vfs_write_resume(mp, 0); } else if ((pmp->pm_flags & MSDOSFSMNT_RONLY) && !vfs_flagopt(mp->mnt_optnew, "ro", NULL, 0)) { /* * If upgrade to read-write by non-root, then verify * that user has necessary permissions on the device. */ odevvp = pmp->pm_odevvp; vn_lock(odevvp, LK_EXCLUSIVE | LK_RETRY); error = VOP_ACCESS(odevvp, VREAD | VWRITE, td->td_ucred, td); if (error) error = priv_check(td, PRIV_VFS_MOUNT_PERM); if (error) { VOP_UNLOCK(odevvp); return (error); } VOP_UNLOCK(odevvp); g_topology_lock(); error = g_access(pmp->pm_cp, 0, 1, 0); g_topology_unlock(); if (error) return (error); /* Now that the volume is modifiable, mark it dirty. */ error = markvoldirty_upgrade(pmp, true, true); if (error) { /* * If dirtying the superblock failed, drop GEOM * 'w' refs (we're still RO). */ g_topology_lock(); (void)g_access(pmp->pm_cp, 0, -1, 0); g_topology_unlock(); return (error); } pmp->pm_fmod = 1; pmp->pm_flags &= ~MSDOSFSMNT_RONLY; MNT_ILOCK(mp); mp->mnt_flag &= ~MNT_RDONLY; MNT_IUNLOCK(mp); } /* * Avoid namei() below. The "from" option is not set. * Update of the devvp is pointless for this case. */ if ((pmp->pm_flags & MSDOSFS_ERR_RO) != 0) return (0); } /* * Not an update, or updating the name: look up the name * and verify that it refers to a sensible disk device. */ if (vfs_getopt(mp->mnt_optnew, "from", (void **)&from, NULL)) return (EINVAL); NDINIT(&ndp, LOOKUP, FOLLOW | LOCKLEAF, UIO_SYSSPACE, from); error = namei(&ndp); if (error) return (error); devvp = ndp.ni_vp; NDFREE_PNBUF(&ndp); if (!vn_isdisk_error(devvp, &error)) { vput(devvp); return (error); } /* * If mount by non-root, then verify that user has necessary * permissions on the device. */ accmode = VREAD; if ((mp->mnt_flag & MNT_RDONLY) == 0) accmode |= VWRITE; error = VOP_ACCESS(devvp, accmode, td->td_ucred, td); if (error) error = priv_check(td, PRIV_VFS_MOUNT_PERM); if (error) { vput(devvp); return (error); } if ((mp->mnt_flag & MNT_UPDATE) == 0) { error = mountmsdosfs(devvp, mp); #ifdef MSDOSFS_DEBUG /* only needed for the printf below */ pmp = VFSTOMSDOSFS(mp); #endif } else { vput(devvp); if (devvp != pmp->pm_odevvp) return (EINVAL); /* XXX needs translation */ } if (error) { vrele(devvp); return (error); } error = update_mp(mp, td); if (error) { if ((mp->mnt_flag & MNT_UPDATE) == 0) msdosfs_unmount(mp, MNT_FORCE); return error; } vfs_mountedfrom(mp, from); #ifdef MSDOSFS_DEBUG printf("msdosfs_mount(): mp %p, pmp %p, inusemap %p\n", mp, pmp, pmp->pm_inusemap); #endif return (0); } /* * The FAT12 and FAT16 file systems use a limited size root directory that * can be created with 1 to 65535 entries for files, directories, or a disk * label (but DOS or Windows creates at most 512 root directory entries). * This function calculates the number of free root directory entries by * counting the non-deleted entries (not starting with 0xE5) and by adding * the amount of never used entries (with the position indicated by an * entry that starts with 0x00). */ static int rootdir_free(struct msdosfsmount* pmp) { struct buf *bp; struct direntry *dep; u_long readsize; int dirclu; int diridx; int dirmax; int dirleft; int ffree; dirclu = pmp->pm_rootdirblk; /* * The msdosfs code ignores pm_RootDirEnts and uses pm_rootdirsize * (measured in DEV_BSIZE) to prevent excess root dir allocations. */ dirleft = howmany(pmp->pm_rootdirsize * DEV_BSIZE, sizeof(struct direntry)); /* Read in chunks of default maximum root directory size */ readsize = 512 * sizeof(struct direntry); #ifdef MSDOSFS_DEBUG printf("rootdir_free: blkpersec=%lu fatblksize=%lu dirsize=%lu " "firstclu=%lu dirclu=%d entries=%d rootdirsize=%lu " "bytespersector=%hu bytepercluster=%lu\n", pmp->pm_BlkPerSec, pmp->pm_fatblocksize, readsize, pmp->pm_firstcluster, dirclu, dirleft, pmp->pm_rootdirsize, pmp->pm_BytesPerSec, pmp->pm_bpcluster); #endif ffree = dirleft; while (dirleft > 0 && ffree > 0) { if (readsize > dirleft * sizeof(struct direntry)) readsize = dirleft * sizeof(struct direntry); #ifdef MSDOSFS_DEBUG printf("rootdir_free: dirclu=%d dirleft=%d readsize=%lu\n", dirclu, dirleft, readsize); #endif if (bread(pmp->pm_devvp, dirclu, readsize, NOCRED, &bp) != 0) { printf("rootdir_free: read error\n"); if (bp != NULL) brelse(bp); return (-1); } dirmax = readsize / sizeof(struct direntry); for (diridx = 0; diridx < dirmax && dirleft > 0; diridx++, dirleft--) { dep = (struct direntry*)bp->b_data + diridx; #ifdef MSDOSFS_DEBUG if (dep->deName[0] == SLOT_DELETED) printf("rootdir_free: idx=%d \n", diridx); else if (dep->deName[0] == SLOT_EMPTY) printf("rootdir_free: idx=%d \n", diridx); else if (dep->deAttributes == ATTR_WIN95) printf("rootdir_free: idx=%d \n", diridx, (dep->deName[0] & 0x1f) + 1); else if (dep->deAttributes & ATTR_VOLUME) printf("rootdir_free: idx=%d label='%11.11s'\n", diridx, dep->deName); else if (dep->deAttributes & ATTR_DIRECTORY) printf("rootdir_free: idx=%d dir='%11.11s'\n", diridx, dep->deName); else printf("rootdir_free: idx=%d file='%11.11s'\n", diridx, dep->deName); #endif if (dep->deName[0] == SLOT_EMPTY) dirleft = 0; else if (dep->deName[0] != SLOT_DELETED) ffree--; } brelse(bp); bp = NULL; dirclu += readsize / DEV_BSIZE; } return (ffree); } static int mountmsdosfs(struct vnode *odevvp, struct mount *mp) { struct msdosfsmount *pmp; struct buf *bp; struct cdev *dev; struct vnode *devvp; union bootsector *bsp; struct byte_bpb33 *b33; struct byte_bpb50 *b50; struct byte_bpb710 *b710; uint8_t SecPerClust; u_long clusters; int ronly, error; struct g_consumer *cp; struct bufobj *bo; bp = NULL; /* This and pmp both used in error_exit. */ pmp = NULL; ronly = (mp->mnt_flag & MNT_RDONLY) != 0; devvp = mntfs_allocvp(mp, odevvp); dev = devvp->v_rdev; if (atomic_cmpset_acq_ptr((uintptr_t *)&dev->si_mountpt, 0, (uintptr_t)mp) == 0) { mntfs_freevp(devvp); return (EBUSY); } g_topology_lock(); error = g_vfs_open(devvp, &cp, "msdosfs", ronly ? 0 : 1); g_topology_unlock(); if (error != 0) { atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); mntfs_freevp(devvp); return (error); } dev_ref(dev); bo = &devvp->v_bufobj; BO_LOCK(&odevvp->v_bufobj); odevvp->v_bufobj.bo_flag |= BO_NOBUFS; BO_UNLOCK(&odevvp->v_bufobj); VOP_UNLOCK(devvp); if (dev->si_iosize_max != 0) mp->mnt_iosize_max = dev->si_iosize_max; if (mp->mnt_iosize_max > maxphys) mp->mnt_iosize_max = maxphys; /* * Read the boot sector of the filesystem, and then check the * boot signature. If not a dos boot sector then error out. * * NOTE: 8192 is a magic size that works for ffs. */ error = bread(devvp, 0, 8192, NOCRED, &bp); if (error) goto error_exit; bp->b_flags |= B_AGE; bsp = (union bootsector *)bp->b_data; b33 = (struct byte_bpb33 *)bsp->bs33.bsBPB; b50 = (struct byte_bpb50 *)bsp->bs50.bsBPB; b710 = (struct byte_bpb710 *)bsp->bs710.bsBPB; #ifndef MSDOSFS_NOCHECKSIG if (bsp->bs50.bsBootSectSig0 != BOOTSIG0 || bsp->bs50.bsBootSectSig1 != BOOTSIG1) { error = EINVAL; goto error_exit; } #endif pmp = malloc(sizeof(*pmp), M_MSDOSFSMNT, M_WAITOK | M_ZERO); pmp->pm_mountp = mp; pmp->pm_cp = cp; pmp->pm_bo = bo; lockinit(&pmp->pm_fatlock, 0, msdosfs_lock_msg, 0, 0); lockinit(&pmp->pm_checkpath_lock, 0, "msdoscp", 0, 0); TASK_INIT(&pmp->pm_rw2ro_task, 0, msdosfs_remount_ro, pmp); /* * Initialize ownerships and permissions, since nothing else will * initialize them iff we are mounting root. */ pmp->pm_uid = UID_ROOT; pmp->pm_gid = GID_WHEEL; pmp->pm_mask = pmp->pm_dirmask = S_IXUSR | S_IXGRP | S_IXOTH | S_IRUSR | S_IRGRP | S_IROTH | S_IWUSR; /* * Compute several useful quantities from the bpb in the * bootsector. Copy in the dos 5 variant of the bpb then fix up * the fields that are different between dos 5 and dos 3.3. */ SecPerClust = b50->bpbSecPerClust; pmp->pm_BytesPerSec = getushort(b50->bpbBytesPerSec); if (pmp->pm_BytesPerSec < DEV_BSIZE) { error = EINVAL; goto error_exit; } pmp->pm_ResSectors = getushort(b50->bpbResSectors); pmp->pm_FATs = b50->bpbFATs; pmp->pm_RootDirEnts = getushort(b50->bpbRootDirEnts); pmp->pm_Sectors = getushort(b50->bpbSectors); pmp->pm_FATsecs = getushort(b50->bpbFATsecs); pmp->pm_SecPerTrack = getushort(b50->bpbSecPerTrack); pmp->pm_Heads = getushort(b50->bpbHeads); pmp->pm_Media = b50->bpbMedia; /* calculate the ratio of sector size to DEV_BSIZE */ pmp->pm_BlkPerSec = pmp->pm_BytesPerSec / DEV_BSIZE; /* * We don't check pm_Heads nor pm_SecPerTrack, because * these may not be set for EFI file systems. We don't * use these anyway, so we're unaffected if they are * invalid. */ if (pmp->pm_BytesPerSec == 0 || SecPerClust == 0) { error = EINVAL; goto error_exit; } if (pmp->pm_Sectors == 0) { pmp->pm_HiddenSects = getulong(b50->bpbHiddenSecs); pmp->pm_HugeSectors = getulong(b50->bpbHugeSectors); } else { pmp->pm_HiddenSects = getushort(b33->bpbHiddenSecs); pmp->pm_HugeSectors = pmp->pm_Sectors; } if (pmp->pm_RootDirEnts == 0) { if (pmp->pm_FATsecs != 0 || getushort(b710->bpbFSVers) != 0) { error = EINVAL; #ifdef MSDOSFS_DEBUG printf("mountmsdosfs(): bad FAT32 filesystem\n"); #endif goto error_exit; } pmp->pm_fatmask = FAT32_MASK; pmp->pm_fatmult = 4; pmp->pm_fatdiv = 1; pmp->pm_FATsecs = getulong(b710->bpbBigFATsecs); if ((getushort(b710->bpbExtFlags) & FATMIRROR) != 0) pmp->pm_curfat = getushort(b710->bpbExtFlags) & FATNUM; else pmp->pm_flags |= MSDOSFS_FATMIRROR; } else pmp->pm_flags |= MSDOSFS_FATMIRROR; /* * Check a few values (could do some more): * - logical sector size: power of 2, >= block size * - sectors per cluster: power of 2, >= 1 * - number of sectors: >= 1, <= size of partition * - number of FAT sectors: >= 1 */ if (SecPerClust == 0 || (SecPerClust & (SecPerClust - 1)) != 0 || pmp->pm_BytesPerSec < DEV_BSIZE || (pmp->pm_BytesPerSec & (pmp->pm_BytesPerSec - 1)) != 0 || pmp->pm_HugeSectors == 0 || pmp->pm_FATsecs == 0 || SecPerClust * pmp->pm_BlkPerSec > MAXBSIZE / DEV_BSIZE) { error = EINVAL; goto error_exit; } if ((off_t)pmp->pm_HugeSectors * pmp->pm_BytesPerSec < pmp->pm_HugeSectors /* overflow */ || (off_t)pmp->pm_HugeSectors * pmp->pm_BytesPerSec > cp->provider->mediasize /* past end of vol */) { error = EINVAL; goto error_exit; } pmp->pm_HugeSectors *= pmp->pm_BlkPerSec; pmp->pm_HiddenSects *= pmp->pm_BlkPerSec; /* XXX not used? */ pmp->pm_FATsecs *= pmp->pm_BlkPerSec; SecPerClust *= pmp->pm_BlkPerSec; pmp->pm_fatblk = pmp->pm_ResSectors * pmp->pm_BlkPerSec; if (FAT32(pmp)) { pmp->pm_rootdirblk = getulong(b710->bpbRootClust); pmp->pm_firstcluster = pmp->pm_fatblk + pmp->pm_FATs * pmp->pm_FATsecs; pmp->pm_fsinfo = getushort(b710->bpbFSInfo) * pmp->pm_BlkPerSec; } else { pmp->pm_rootdirblk = pmp->pm_fatblk + pmp->pm_FATs * pmp->pm_FATsecs; pmp->pm_rootdirsize = howmany(pmp->pm_RootDirEnts * sizeof(struct direntry), DEV_BSIZE); /* in blocks */ pmp->pm_firstcluster = pmp->pm_rootdirblk + pmp->pm_rootdirsize; } if (pmp->pm_HugeSectors <= pmp->pm_firstcluster) { error = EINVAL; goto error_exit; } pmp->pm_maxcluster = (pmp->pm_HugeSectors - pmp->pm_firstcluster) / SecPerClust + 1; pmp->pm_fatsize = pmp->pm_FATsecs * DEV_BSIZE; if (pmp->pm_fatmask == 0) { /* * The last 10 (or 16?) clusters are reserved and must not * be allocated for data. */ if (pmp->pm_maxcluster < (CLUST_RSRVD & FAT12_MASK)) { /* * This will usually be a floppy disk. This size makes * sure that one FAT entry will not be split across * multiple blocks. */ pmp->pm_fatmask = FAT12_MASK; pmp->pm_fatmult = 3; pmp->pm_fatdiv = 2; } else { pmp->pm_fatmask = FAT16_MASK; pmp->pm_fatmult = 2; pmp->pm_fatdiv = 1; } } clusters = (pmp->pm_fatsize / pmp->pm_fatmult) * pmp->pm_fatdiv ; if (pmp->pm_maxcluster >= clusters) { #ifdef MSDOSFS_DEBUG printf("Warning: number of clusters (%ld) exceeds FAT " "capacity (%ld)\n", pmp->pm_maxcluster - 1, clusters); #endif pmp->pm_maxcluster = clusters - 1; } if (FAT12(pmp)) pmp->pm_fatblocksize = 3 * 512; else pmp->pm_fatblocksize = PAGE_SIZE; pmp->pm_fatblocksize = roundup(pmp->pm_fatblocksize, pmp->pm_BytesPerSec); pmp->pm_fatblocksec = pmp->pm_fatblocksize / DEV_BSIZE; pmp->pm_bnshift = ffs(DEV_BSIZE) - 1; /* * Compute mask and shift value for isolating cluster relative byte * offsets and cluster numbers from a file offset. */ pmp->pm_bpcluster = SecPerClust * DEV_BSIZE; pmp->pm_crbomask = pmp->pm_bpcluster - 1; pmp->pm_cnshift = ffs(pmp->pm_bpcluster) - 1; /* * Check for valid cluster size * must be a power of 2 */ if ((pmp->pm_bpcluster ^ (1 << pmp->pm_cnshift)) != 0) { error = EINVAL; goto error_exit; } /* * Release the bootsector buffer. */ brelse(bp); bp = NULL; /* * Check the fsinfo sector if we have one. Silently fix up our * in-core copy of fp->fsinxtfree if it is unknown (0xffffffff) * or too large. Ignore fp->fsinfree for now, since we need to * read the entire FAT anyway to fill the inuse map. */ if (pmp->pm_fsinfo) { struct fsinfo *fp; if ((error = bread(devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, NOCRED, &bp)) != 0) goto error_exit; fp = (struct fsinfo *)bp->b_data; if (!bcmp(fp->fsisig1, "RRaA", 4) && !bcmp(fp->fsisig2, "rrAa", 4) && !bcmp(fp->fsisig3, "\0\0\125\252", 4)) { pmp->pm_nxtfree = getulong(fp->fsinxtfree); if (pmp->pm_nxtfree > pmp->pm_maxcluster) pmp->pm_nxtfree = CLUST_FIRST; } else pmp->pm_fsinfo = 0; brelse(bp); bp = NULL; } /* * Finish initializing pmp->pm_nxtfree (just in case the first few * sectors aren't properly reserved in the FAT). This completes * the fixup for fp->fsinxtfree, and fixes up the zero-initialized * value if there is no fsinfo. We will use pmp->pm_nxtfree * internally even if there is no fsinfo. */ if (pmp->pm_nxtfree < CLUST_FIRST) pmp->pm_nxtfree = CLUST_FIRST; /* * Allocate memory for the bitmap of allocated clusters, and then * fill it in. */ pmp->pm_inusemap = malloc(howmany(pmp->pm_maxcluster + 1, N_INUSEBITS) * sizeof(*pmp->pm_inusemap), M_MSDOSFSFAT, M_WAITOK); /* * fillinusemap() needs pm_devvp. */ pmp->pm_devvp = devvp; pmp->pm_odevvp = odevvp; pmp->pm_dev = dev; /* * Have the inuse map filled in. */ MSDOSFS_LOCK_MP(pmp); error = fillinusemap(pmp); MSDOSFS_UNLOCK_MP(pmp); if (error != 0) goto error_exit; /* * If they want FAT updates to be synchronous then let them suffer * the performance degradation in exchange for the on disk copy of * the FAT being correct just about all the time. I suppose this * would be a good thing to turn on if the kernel is still flakey. */ if (mp->mnt_flag & MNT_SYNCHRONOUS) pmp->pm_flags |= MSDOSFSMNT_WAITONFAT; /* * Finish up. */ if (ronly) pmp->pm_flags |= MSDOSFSMNT_RONLY; else { if ((error = markvoldirty(pmp, 1)) != 0) goto error_exit; pmp->pm_fmod = 1; } if (FAT32(pmp)) { pmp->pm_rootdirfree = 0; } else { pmp->pm_rootdirfree = rootdir_free(pmp); if (pmp->pm_rootdirfree < 0) goto error_exit; } mp->mnt_data = pmp; mp->mnt_stat.f_fsid.val[0] = dev2udev(dev); mp->mnt_stat.f_fsid.val[1] = mp->mnt_vfc->vfc_typenum; MNT_ILOCK(mp); mp->mnt_flag |= MNT_LOCAL; mp->mnt_kern_flag |= MNTK_USES_BCACHE | MNTK_NO_IOPF; MNT_IUNLOCK(mp); return (0); error_exit: if (bp != NULL) brelse(bp); if (cp != NULL) { g_topology_lock(); g_vfs_close(cp); g_topology_unlock(); } if (pmp != NULL) { lockdestroy(&pmp->pm_fatlock); lockdestroy(&pmp->pm_checkpath_lock); free(pmp->pm_inusemap, M_MSDOSFSFAT); free(pmp, M_MSDOSFSMNT); mp->mnt_data = NULL; } BO_LOCK(&odevvp->v_bufobj); odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS; BO_UNLOCK(&odevvp->v_bufobj); atomic_store_rel_ptr((uintptr_t *)&dev->si_mountpt, 0); vn_lock(devvp, LK_EXCLUSIVE | LK_RETRY); mntfs_freevp(devvp); dev_rel(dev); return (error); } /* * Unmount the filesystem described by mp. */ static int msdosfs_unmount(struct mount *mp, int mntflags) { struct msdosfsmount *pmp; int error, flags; bool susp; error = flags = 0; pmp = VFSTOMSDOSFS(mp); susp = (pmp->pm_flags & MSDOSFSMNT_RONLY) == 0; if (susp) { error = vfs_write_suspend_umnt(mp); if (error != 0) return (error); } if ((mntflags & MNT_FORCE) != 0) flags |= FORCECLOSE; error = vflush(mp, 0, flags, curthread); if (error != 0 && error != ENXIO) { if (susp) vfs_write_resume(mp, VR_START_WRITE); return (error); } if (susp) { error = markvoldirty(pmp, 0); if (error != 0 && error != ENXIO) { if (susp) vfs_write_resume(mp, VR_START_WRITE); (void)markvoldirty(pmp, 1); return (error); } } if (pmp->pm_flags & MSDOSFSMNT_KICONV && msdosfs_iconv) { if (pmp->pm_w2u) msdosfs_iconv->close(pmp->pm_w2u); if (pmp->pm_u2w) msdosfs_iconv->close(pmp->pm_u2w); if (pmp->pm_d2u) msdosfs_iconv->close(pmp->pm_d2u); if (pmp->pm_u2d) msdosfs_iconv->close(pmp->pm_u2d); } #ifdef MSDOSFS_DEBUG { struct vnode *vp = pmp->pm_devvp; struct bufobj *bo; bo = &vp->v_bufobj; BO_LOCK(bo); VI_LOCK(vp); vn_printf(vp, "msdosfs_umount(): just before calling VOP_CLOSE()\n"); printf("freef %p, freeb %p, mount %p\n", TAILQ_NEXT(vp, v_vnodelist), vp->v_vnodelist.tqe_prev, vp->v_mount); printf("cleanblkhd %p, dirtyblkhd %p, numoutput %d, type %d\n", TAILQ_FIRST(&vp->v_bufobj.bo_clean.bv_hd), TAILQ_FIRST(&vp->v_bufobj.bo_dirty.bv_hd), vp->v_bufobj.bo_numoutput, vp->v_type); VI_UNLOCK(vp); BO_UNLOCK(bo); } #endif if (susp) vfs_write_resume(mp, VR_START_WRITE); vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); g_topology_lock(); g_vfs_close(pmp->pm_cp); g_topology_unlock(); BO_LOCK(&pmp->pm_odevvp->v_bufobj); pmp->pm_odevvp->v_bufobj.bo_flag &= ~BO_NOBUFS; BO_UNLOCK(&pmp->pm_odevvp->v_bufobj); atomic_store_rel_ptr((uintptr_t *)&pmp->pm_dev->si_mountpt, 0); mntfs_freevp(pmp->pm_devvp); vrele(pmp->pm_odevvp); dev_rel(pmp->pm_dev); free(pmp->pm_inusemap, M_MSDOSFSFAT); lockdestroy(&pmp->pm_fatlock); lockdestroy(&pmp->pm_checkpath_lock); free(pmp, M_MSDOSFSMNT); mp->mnt_data = NULL; return (error); } static void msdosfs_remount_ro(void *arg, int pending) { struct msdosfsmount *pmp; int error; pmp = arg; MSDOSFS_LOCK_MP(pmp); if ((pmp->pm_flags & MSDOSFS_ERR_RO) != 0) { while ((pmp->pm_flags & MSDOSFS_ERR_RO) != 0) msleep(&pmp->pm_flags, &pmp->pm_fatlock, PVFS, "msdoserrro", hz); } else if ((pmp->pm_mountp->mnt_flag & MNT_RDONLY) == 0) { pmp->pm_flags |= MSDOSFS_ERR_RO; MSDOSFS_UNLOCK_MP(pmp); printf("%s: remounting read-only due to corruption\n", pmp->pm_mountp->mnt_stat.f_mntfromname); error = vfs_remount_ro(pmp->pm_mountp); if (error != 0) printf("%s: remounting read-only failed: error %d\n", pmp->pm_mountp->mnt_stat.f_mntfromname, error); else printf("remounted %s read-only\n", pmp->pm_mountp->mnt_stat.f_mntfromname); MSDOSFS_LOCK_MP(pmp); pmp->pm_flags &= ~MSDOSFS_ERR_RO; wakeup(&pmp->pm_flags); } MSDOSFS_UNLOCK_MP(pmp); while (--pending >= 0) vfs_unbusy(pmp->pm_mountp); } void msdosfs_integrity_error(struct msdosfsmount *pmp) { int error; error = vfs_busy(pmp->pm_mountp, MBF_NOWAIT); if (error == 0) { error = taskqueue_enqueue(taskqueue_thread, &pmp->pm_rw2ro_task); if (error != 0) { printf("%s: integrity error scheduling failed, " "error %d\n", pmp->pm_mountp->mnt_stat.f_mntfromname, error); vfs_unbusy(pmp->pm_mountp); } } else { printf("%s: integrity error busying failed, error %d\n", pmp->pm_mountp->mnt_stat.f_mntfromname, error); } } static int msdosfs_root(struct mount *mp, int flags, struct vnode **vpp) { struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); struct denode *ndep; int error; #ifdef MSDOSFS_DEBUG printf("msdosfs_root(); mp %p, pmp %p\n", mp, pmp); #endif error = deget(pmp, MSDOSFSROOT, MSDOSFSROOT_OFS, LK_EXCLUSIVE, &ndep); if (error) return (error); *vpp = DETOV(ndep); return (0); } static int msdosfs_statfs(struct mount *mp, struct statfs *sbp) { struct msdosfsmount *pmp; pmp = VFSTOMSDOSFS(mp); sbp->f_bsize = pmp->pm_bpcluster; sbp->f_iosize = pmp->pm_bpcluster; sbp->f_blocks = pmp->pm_maxcluster - CLUST_FIRST + 1; sbp->f_bfree = pmp->pm_freeclustercount; sbp->f_bavail = pmp->pm_freeclustercount; sbp->f_files = howmany(pmp->pm_rootdirsize * DEV_BSIZE, sizeof(struct direntry)); sbp->f_ffree = pmp->pm_rootdirfree; return (0); } /* * If we have an FSInfo block, update it. */ static int msdosfs_fsiflush(struct msdosfsmount *pmp, int waitfor) { struct fsinfo *fp; struct buf *bp; int error; MSDOSFS_LOCK_MP(pmp); if (pmp->pm_fsinfo == 0 || (pmp->pm_flags & MSDOSFS_FSIMOD) == 0) { error = 0; goto unlock; } error = bread(pmp->pm_devvp, pmp->pm_fsinfo, pmp->pm_BytesPerSec, NOCRED, &bp); if (error != 0) { goto unlock; } fp = (struct fsinfo *)bp->b_data; putulong(fp->fsinfree, pmp->pm_freeclustercount); putulong(fp->fsinxtfree, pmp->pm_nxtfree); pmp->pm_flags &= ~MSDOSFS_FSIMOD; if (waitfor == MNT_WAIT) error = bwrite(bp); else bawrite(bp); unlock: MSDOSFS_UNLOCK_MP(pmp); return (error); } static int msdosfs_sync(struct mount *mp, int waitfor) { struct vnode *vp, *nvp; struct thread *td; struct denode *dep; struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); int error, allerror = 0; td = curthread; /* * If we ever switch to not updating all of the FATs all the time, * this would be the place to update them from the first one. */ if (pmp->pm_fmod != 0) { if (pmp->pm_flags & MSDOSFSMNT_RONLY) panic("msdosfs_sync: rofs mod"); else { /* update FATs here */ } } /* * Write back each (modified) denode. */ loop: MNT_VNODE_FOREACH_ALL(vp, mp, nvp) { if (vp->v_type == VNON) { VI_UNLOCK(vp); continue; } dep = VTODE(vp); if ((dep->de_flag & (DE_ACCESS | DE_CREATE | DE_UPDATE | DE_MODIFIED)) == 0 && (vp->v_bufobj.bo_dirty.bv_cnt == 0 || waitfor == MNT_LAZY)) { VI_UNLOCK(vp); continue; } error = vget(vp, LK_EXCLUSIVE | LK_NOWAIT | LK_INTERLOCK); if (error) { if (error == ENOENT) { MNT_VNODE_FOREACH_ALL_ABORT(mp, nvp); goto loop; } continue; } error = VOP_FSYNC(vp, waitfor, td); if (error) allerror = error; vput(vp); } /* * Flush filesystem control info. */ if (waitfor != MNT_LAZY) { vn_lock(pmp->pm_devvp, LK_EXCLUSIVE | LK_RETRY); error = VOP_FSYNC(pmp->pm_devvp, waitfor, td); if (error) allerror = error; VOP_UNLOCK(pmp->pm_devvp); } error = msdosfs_fsiflush(pmp, waitfor); if (error != 0) allerror = error; if (allerror == 0 && waitfor == MNT_SUSPEND) { MNT_ILOCK(mp); mp->mnt_kern_flag |= MNTK_SUSPEND2 | MNTK_SUSPENDED; MNT_IUNLOCK(mp); } return (allerror); } static int msdosfs_fhtovp(struct mount *mp, struct fid *fhp, int flags, struct vnode **vpp) { struct msdosfsmount *pmp = VFSTOMSDOSFS(mp); struct defid *defhp = (struct defid *) fhp; struct denode *dep; int error; error = deget(pmp, defhp->defid_dirclust, defhp->defid_dirofs, LK_EXCLUSIVE, &dep); if (error) { *vpp = NULLVP; return (error); } *vpp = DETOV(dep); vnode_create_vobject(*vpp, dep->de_FileSize, curthread); return (0); } static struct vfsops msdosfs_vfsops = { .vfs_fhtovp = msdosfs_fhtovp, .vfs_mount = msdosfs_mount, .vfs_cmount = msdosfs_cmount, .vfs_root = msdosfs_root, .vfs_statfs = msdosfs_statfs, .vfs_sync = msdosfs_sync, .vfs_unmount = msdosfs_unmount, }; VFS_SET(msdosfs_vfsops, msdosfs, 0); MODULE_VERSION(msdosfs, 1);