diff --git a/sys/fs/msdosfs/msdosfs_denode.c b/sys/fs/msdosfs/msdosfs_denode.c index 8ca9fa38b1cf..2d682fa403dc 100644 --- a/sys/fs/msdosfs/msdosfs_denode.c +++ b/sys/fs/msdosfs/msdosfs_denode.c @@ -1,636 +1,637 @@ /* $FreeBSD$ */ /* $NetBSD: msdosfs_denode.c,v 1.28 1998/02/10 14:10:00 mrg 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 static MALLOC_DEFINE(M_MSDOSFSNODE, "msdosfs_node", "MSDOSFS vnode private part"); static int de_vncmpf(struct vnode *vp, void *arg) { struct denode *de; uint64_t *a; a = arg; de = VTODE(vp); return (de->de_inode != *a) || (de->de_refcnt <= 0); } /* * If deget() succeeds it returns with the gotten denode locked(). * * pmp - address of msdosfsmount structure of the filesystem containing * the denode of interest. The address of * the msdosfsmount structure are used. * dirclust - which cluster bp contains, if dirclust is 0 (root directory) * diroffset is relative to the beginning of the root directory, * otherwise it is cluster relative. * diroffset - offset past begin of cluster of denode we want * lkflags - locking flags (LK_NOWAIT) * depp - returns the address of the gotten denode. */ int deget(struct msdosfsmount *pmp, u_long dirclust, u_long diroffset, int lkflags, struct denode **depp) { int error; uint64_t inode; struct mount *mntp = pmp->pm_mountp; struct direntry *direntptr; struct denode *ldep; struct vnode *nvp, *xvp; struct buf *bp; #ifdef MSDOSFS_DEBUG printf("deget(pmp %p, dirclust %lu, diroffset %lx, flags %#x, " "depp %p)\n", pmp, dirclust, diroffset, flags, depp); #endif MPASS((lkflags & LK_TYPE_MASK) == LK_EXCLUSIVE); /* * On FAT32 filesystems, root is a (more or less) normal * directory */ if (FAT32(pmp) && dirclust == MSDOSFSROOT) dirclust = pmp->pm_rootdirblk; /* * See if the denode is in the denode cache. Use the location of * the directory entry to compute the hash value. For subdir use * address of "." entry. For root dir (if not FAT32) use cluster * MSDOSFSROOT, offset MSDOSFSROOT_OFS * * NOTE: de_vncmpf will explicitly skip any denodes that do not have * a de_refcnt > 0. This insures that that we do not attempt to use * a denode that represents an unlinked but still open file. * These files are not to be accessible even when the directory * entry that represented the file happens to be reused while the * deleted file is still open. */ inode = (uint64_t)pmp->pm_bpcluster * dirclust + diroffset; error = vfs_hash_get(mntp, inode, lkflags, curthread, &nvp, de_vncmpf, &inode); if (error) return (error); if (nvp != NULL) { *depp = VTODE(nvp); if ((*depp)->de_dirclust != dirclust) { printf("%s: wrong dir cluster %lu %lu\n", pmp->pm_mountp->mnt_stat.f_mntonname, (*depp)->de_dirclust, dirclust); goto badoff; } if ((*depp)->de_diroffset != diroffset) { printf("%s: wrong dir offset %lu %lu\n", pmp->pm_mountp->mnt_stat.f_mntonname, (*depp)->de_diroffset, diroffset); goto badoff; } return (0); badoff: vgone(nvp); vput(nvp); + msdosfs_integrity_error(pmp); return (EBADF); } ldep = malloc(sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK | M_ZERO); /* * Directory entry was not in cache, have to create a vnode and * copy it from the passed disk buffer. */ /* getnewvnode() does a VREF() on the vnode */ error = getnewvnode("msdosfs", mntp, &msdosfs_vnodeops, &nvp); if (error) { *depp = NULL; free(ldep, M_MSDOSFSNODE); return error; } nvp->v_data = ldep; ldep->de_vnode = nvp; ldep->de_flag = 0; ldep->de_dirclust = dirclust; ldep->de_diroffset = diroffset; ldep->de_inode = inode; cluster_init_vn(&ldep->de_clusterw); lockmgr(nvp->v_vnlock, LK_EXCLUSIVE, NULL); VN_LOCK_AREC(nvp); /* for doscheckpath */ fc_purge(ldep, 0); /* init the FAT cache for this denode */ error = insmntque(nvp, mntp); if (error != 0) { free(ldep, M_MSDOSFSNODE); *depp = NULL; return (error); } error = vfs_hash_insert(nvp, inode, lkflags, curthread, &xvp, de_vncmpf, &inode); if (error) { *depp = NULL; return (error); } if (xvp != NULL) { *depp = xvp->v_data; return (0); } ldep->de_pmp = pmp; ldep->de_refcnt = 1; /* * Copy the directory entry into the denode area of the vnode. */ if ((dirclust == MSDOSFSROOT || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk)) && diroffset == MSDOSFSROOT_OFS) { /* * Directory entry for the root directory. There isn't one, * so we manufacture one. We should probably rummage * through the root directory and find a label entry (if it * exists), and then use the time and date from that entry * as the time and date for the root denode. */ nvp->v_vflag |= VV_ROOT; /* should be further down XXX */ ldep->de_Attributes = ATTR_DIRECTORY; ldep->de_LowerCase = 0; if (FAT32(pmp)) ldep->de_StartCluster = pmp->pm_rootdirblk; /* de_FileSize will be filled in further down */ else { ldep->de_StartCluster = MSDOSFSROOT; ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE; } /* * fill in time and date so that fattime2timespec() doesn't * spit up when called from msdosfs_getattr() with root * denode */ ldep->de_CHun = 0; ldep->de_CTime = 0x0000; /* 00:00:00 */ ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT) | (1 << DD_DAY_SHIFT); /* Jan 1, 1980 */ ldep->de_ADate = ldep->de_CDate; ldep->de_MTime = ldep->de_CTime; ldep->de_MDate = ldep->de_CDate; /* leave the other fields as garbage */ } else { error = readep(pmp, dirclust, diroffset, &bp, &direntptr); if (error) { /* * The denode does not contain anything useful, so * it would be wrong to leave it on its hash chain. * Arrange for vput() to just forget about it. */ ldep->de_Name[0] = SLOT_DELETED; vgone(nvp); vput(nvp); *depp = NULL; return (error); } (void)DE_INTERNALIZE(ldep, direntptr); brelse(bp); } /* * Fill in a few fields of the vnode and finish filling in the * denode. Then return the address of the found denode. */ if (ldep->de_Attributes & ATTR_DIRECTORY) { /* * Since DOS directory entries that describe directories * have 0 in the filesize field, we take this opportunity * to find out the length of the directory and plug it into * the denode structure. */ u_long size; /* * XXX it sometimes happens that the "." entry has cluster * number 0 when it shouldn't. Use the actual cluster number * instead of what is written in directory entry. */ if (diroffset == 0 && ldep->de_StartCluster != dirclust) { #ifdef MSDOSFS_DEBUG printf("deget(): \".\" entry at clust %lu != %lu\n", dirclust, ldep->de_StartCluster); #endif ldep->de_StartCluster = dirclust; } nvp->v_type = VDIR; if (ldep->de_StartCluster != MSDOSFSROOT) { error = pcbmap(ldep, 0xffff, 0, &size, 0); if (error == E2BIG) { ldep->de_FileSize = de_cn2off(pmp, size); error = 0; } else { #ifdef MSDOSFS_DEBUG printf("deget(): pcbmap returned %d\n", error); #endif } } } else nvp->v_type = VREG; ldep->de_modrev = init_va_filerev(); *depp = ldep; return (0); } int deupdat(struct denode *dep, int waitfor) { struct direntry dir; struct timespec ts; struct buf *bp; struct direntry *dirp; int error; if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY) { dep->de_flag &= ~(DE_UPDATE | DE_CREATE | DE_ACCESS | DE_MODIFIED); return (0); } vfs_timestamp(&ts); DETIMES(dep, &ts, &ts, &ts); if ((dep->de_flag & DE_MODIFIED) == 0 && waitfor == 0) return (0); dep->de_flag &= ~DE_MODIFIED; if (DETOV(dep)->v_vflag & VV_ROOT) return (EINVAL); if (dep->de_refcnt <= 0) return (0); error = readde(dep, &bp, &dirp); if (error) return (error); DE_EXTERNALIZE(&dir, dep); if (bcmp(dirp, &dir, sizeof(dir)) == 0) { if (waitfor == 0 || (bp->b_flags & B_DELWRI) == 0) { brelse(bp); return (0); } } else *dirp = dir; if ((DETOV(dep)->v_mount->mnt_flag & MNT_NOCLUSTERW) == 0) bp->b_flags |= B_CLUSTEROK; if (waitfor) error = bwrite(bp); else if (vm_page_count_severe() || buf_dirty_count_severe()) bawrite(bp); else bdwrite(bp); return (error); } /* * Truncate the file described by dep to the length specified by length. */ int detrunc(struct denode *dep, u_long length, int flags, struct ucred *cred) { int error; int allerror; u_long eofentry; u_long chaintofree; daddr_t bn; int boff; int isadir = dep->de_Attributes & ATTR_DIRECTORY; struct buf *bp; struct msdosfsmount *pmp = dep->de_pmp; #ifdef MSDOSFS_DEBUG printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags); #endif /* * Disallow attempts to truncate the root directory since it is of * fixed size. That's just the way dos filesystems are. We use * the VROOT bit in the vnode because checking for the directory * bit and a startcluster of 0 in the denode is not adequate to * recognize the root directory at this point in a file or * directory's life. */ if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) { #ifdef MSDOSFS_DEBUG printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n", dep->de_dirclust, dep->de_diroffset); #endif return (EINVAL); } if (dep->de_FileSize < length) { vnode_pager_setsize(DETOV(dep), length); return deextend(dep, length, cred); } /* * If the desired length is 0 then remember the starting cluster of * the file and set the StartCluster field in the directory entry * to 0. If the desired length is not zero, then get the number of * the last cluster in the shortened file. Then get the number of * the first cluster in the part of the file that is to be freed. * Then set the next cluster pointer in the last cluster of the * file to CLUST_EOFE. */ if (length == 0) { chaintofree = dep->de_StartCluster; dep->de_StartCluster = 0; eofentry = ~0; } else { error = pcbmap(dep, de_clcount(pmp, length) - 1, 0, &eofentry, 0); if (error) { #ifdef MSDOSFS_DEBUG printf("detrunc(): pcbmap fails %d\n", error); #endif return (error); } } fc_purge(dep, de_clcount(pmp, length)); /* * If the new length is not a multiple of the cluster size then we * must zero the tail end of the new last cluster in case it * becomes part of the file again because of a seek. */ if ((boff = length & pmp->pm_crbomask) != 0) { if (isadir) { bn = cntobn(pmp, eofentry); error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, NOCRED, &bp); } else { error = bread(DETOV(dep), de_cluster(pmp, length), pmp->pm_bpcluster, cred, &bp); } if (error) { #ifdef MSDOSFS_DEBUG printf("detrunc(): bread fails %d\n", error); #endif return (error); } memset(bp->b_data + boff, 0, pmp->pm_bpcluster - boff); if ((flags & IO_SYNC) != 0) bwrite(bp); else bdwrite(bp); } /* * Write out the updated directory entry. Even if the update fails * we free the trailing clusters. */ dep->de_FileSize = length; if (!isadir) dep->de_flag |= DE_UPDATE | DE_MODIFIED; allerror = vtruncbuf(DETOV(dep), length, pmp->pm_bpcluster); #ifdef MSDOSFS_DEBUG if (allerror) printf("detrunc(): vtruncbuf error %d\n", allerror); #endif error = deupdat(dep, !DOINGASYNC((DETOV(dep)))); if (error != 0 && allerror == 0) allerror = error; #ifdef MSDOSFS_DEBUG printf("detrunc(): allerror %d, eofentry %lu\n", allerror, eofentry); #endif /* * If we need to break the cluster chain for the file then do it * now. */ if (eofentry != ~0) { error = fatentry(FAT_GET_AND_SET, pmp, eofentry, &chaintofree, CLUST_EOFE); if (error) { #ifdef MSDOSFS_DEBUG printf("detrunc(): fatentry errors %d\n", error); #endif return (error); } fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1), eofentry); } /* * Now free the clusters removed from the file because of the * truncation. */ if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree)) freeclusterchain(pmp, chaintofree); return (allerror); } /* * Extend the file described by dep to length specified by length. */ int deextend(struct denode *dep, u_long length, struct ucred *cred) { struct msdosfsmount *pmp = dep->de_pmp; u_long count; int error; /* * The root of a DOS filesystem cannot be extended. */ if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) return (EINVAL); /* * Directories cannot be extended. */ if (dep->de_Attributes & ATTR_DIRECTORY) return (EISDIR); if (length <= dep->de_FileSize) panic("deextend: file too large"); /* * Compute the number of clusters to allocate. */ count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize); if (count > 0) { if (count > pmp->pm_freeclustercount) return (ENOSPC); error = extendfile(dep, count, NULL, NULL, DE_CLEAR); if (error) { /* truncate the added clusters away again */ (void) detrunc(dep, dep->de_FileSize, 0, cred); return (error); } } dep->de_FileSize = length; dep->de_flag |= DE_UPDATE | DE_MODIFIED; return (deupdat(dep, !DOINGASYNC(DETOV(dep)))); } /* * Move a denode to its correct hash queue after the file it represents has * been moved to a new directory. */ void reinsert(struct denode *dep) { struct vnode *vp; /* * Fix up the denode cache. If the denode is for a directory, * there is nothing to do since the hash is based on the starting * cluster of the directory file and that hasn't changed. If for a * file the hash is based on the location of the directory entry, * so we must remove it from the cache and re-enter it with the * hash based on the new location of the directory entry. */ #if 0 if (dep->de_Attributes & ATTR_DIRECTORY) return; #endif vp = DETOV(dep); dep->de_inode = (uint64_t)dep->de_pmp->pm_bpcluster * dep->de_dirclust + dep->de_diroffset; vfs_hash_rehash(vp, dep->de_inode); } int msdosfs_reclaim(struct vop_reclaim_args *ap) { struct vnode *vp = ap->a_vp; struct denode *dep = VTODE(vp); #ifdef MSDOSFS_DEBUG printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n", dep, dep->de_Name, dep->de_refcnt); #endif /* * Remove the denode from its hash chain. */ vfs_hash_remove(vp); /* * Purge old data structures associated with the denode. */ #if 0 /* XXX */ dep->de_flag = 0; #endif free(dep, M_MSDOSFSNODE); vp->v_data = NULL; return (0); } int msdosfs_inactive(struct vop_inactive_args *ap) { struct vnode *vp = ap->a_vp; struct denode *dep = VTODE(vp); int error = 0; #ifdef MSDOSFS_DEBUG printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]); #endif /* * Ignore denodes related to stale file handles. */ if (dep->de_Name[0] == SLOT_DELETED || dep->de_Name[0] == SLOT_EMPTY) goto out; /* * If the file has been deleted and it is on a read/write * filesystem, then truncate the file, and mark the directory slot * as empty. (This may not be necessary for the dos filesystem.) */ #ifdef MSDOSFS_DEBUG printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %llx, MNT_RDONLY %llx\n", dep, dep->de_refcnt, (unsigned long long)vp->v_mount->mnt_flag, (unsigned long long)MNT_RDONLY); #endif if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { error = detrunc(dep, (u_long) 0, 0, NOCRED); dep->de_flag |= DE_UPDATE; dep->de_Name[0] = SLOT_DELETED; } deupdat(dep, 0); out: /* * If we are done with the denode, reclaim it * so that it can be reused immediately. */ #ifdef MSDOSFS_DEBUG printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vrefcnt(vp), dep->de_Name[0]); #endif if (dep->de_Name[0] == SLOT_DELETED || dep->de_Name[0] == SLOT_EMPTY) vrecycle(vp); return (error); } diff --git a/sys/fs/msdosfs/msdosfs_fat.c b/sys/fs/msdosfs/msdosfs_fat.c index fc1db705989b..e6d9b671e7d7 100644 --- a/sys/fs/msdosfs/msdosfs_fat.c +++ b/sys/fs/msdosfs/msdosfs_fat.c @@ -1,1209 +1,1210 @@ /* $FreeBSD$ */ /* $NetBSD: msdosfs_fat.c,v 1.28 1997/11/17 15:36:49 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 #define FULL_RUN ((u_int)0xffffffff) static int chainalloc(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got); static int chainlength(struct msdosfsmount *pmp, u_long start, u_long count); static void fatblock(struct msdosfsmount *pmp, u_long ofs, u_long *bnp, u_long *sizep, u_long *bop); static int fatchain(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith); static void fc_lookup(struct denode *dep, u_long findcn, u_long *frcnp, u_long *fsrcnp); static void updatefats(struct msdosfsmount *pmp, struct buf *bp, u_long fatbn); static __inline void usemap_alloc(struct msdosfsmount *pmp, u_long cn); static int usemap_free(struct msdosfsmount *pmp, u_long cn); static int clusteralloc1(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got); static void fatblock(struct msdosfsmount *pmp, u_long ofs, u_long *bnp, u_long *sizep, u_long *bop) { u_long bn, size; bn = ofs / pmp->pm_fatblocksize * pmp->pm_fatblocksec; size = min(pmp->pm_fatblocksec, pmp->pm_FATsecs - bn) * DEV_BSIZE; bn += pmp->pm_fatblk + pmp->pm_curfat * pmp->pm_FATsecs; if (bnp) *bnp = bn; if (sizep) *sizep = size; if (bop) *bop = ofs % pmp->pm_fatblocksize; } /* * Map the logical cluster number of a file into a physical disk sector * that is filesystem relative. * * dep - address of denode representing the file of interest * findcn - file relative cluster whose filesystem relative cluster number * and/or block number are/is to be found * bnp - address of where to place the filesystem relative block number. * If this pointer is null then don't return this quantity. * cnp - address of where to place the filesystem relative cluster number. * If this pointer is null then don't return this quantity. * sp - pointer to returned block size * * NOTE: Either bnp or cnp must be non-null. * This function has one side effect. If the requested file relative cluster * is beyond the end of file, then the actual number of clusters in the file * is returned in *cnp. This is useful for determining how long a directory is. * If cnp is null, nothing is returned. */ int pcbmap(struct denode *dep, u_long findcn, daddr_t *bnp, u_long *cnp, int *sp) { int error; u_long i; u_long cn; u_long prevcn = 0; /* XXX: prevcn could be used unititialized */ u_long byteoffset; u_long bn; u_long bo; struct buf *bp = NULL; u_long bp_bn = -1; struct msdosfsmount *pmp = dep->de_pmp; u_long bsize; KASSERT(bnp != NULL || cnp != NULL || sp != NULL, ("pcbmap: extra call")); ASSERT_VOP_ELOCKED(DETOV(dep), "pcbmap"); cn = dep->de_StartCluster; /* * The "file" that makes up the root directory is contiguous, * permanently allocated, of fixed size, and is not made up of * clusters. If the cluster number is beyond the end of the root * directory, then return the number of clusters in the file. */ if (cn == MSDOSFSROOT) { if (dep->de_Attributes & ATTR_DIRECTORY) { if (de_cn2off(pmp, findcn) >= dep->de_FileSize) { if (cnp) *cnp = de_bn2cn(pmp, pmp->pm_rootdirsize); return (E2BIG); } if (bnp) *bnp = pmp->pm_rootdirblk + de_cn2bn(pmp, findcn); if (cnp) *cnp = MSDOSFSROOT; if (sp) *sp = min(pmp->pm_bpcluster, dep->de_FileSize - de_cn2off(pmp, findcn)); return (0); } else { /* just an empty file */ if (cnp) *cnp = 0; return (E2BIG); } } /* * All other files do I/O in cluster sized blocks */ if (sp) *sp = pmp->pm_bpcluster; /* * Rummage around in the FAT cache, maybe we can avoid tromping * through every FAT entry for the file. And, keep track of how far * off the cache was from where we wanted to be. */ i = 0; fc_lookup(dep, findcn, &i, &cn); /* * Handle all other files or directories the normal way. */ for (; i < findcn; i++) { /* * Stop with all reserved clusters, not just with EOF. */ if ((cn | ~pmp->pm_fatmask) >= CLUST_RSRVD) goto hiteof; byteoffset = FATOFS(pmp, cn); fatblock(pmp, byteoffset, &bn, &bsize, &bo); if (bn != bp_bn) { if (bp) brelse(bp); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) { return (error); } bp_bn = bn; } prevcn = cn; if (bo >= bsize) { if (bp) brelse(bp); return (EIO); } if (FAT32(pmp)) cn = getulong(bp->b_data + bo); else cn = getushort(bp->b_data + bo); if (FAT12(pmp) && (prevcn & 1)) cn >>= 4; cn &= pmp->pm_fatmask; /* * Force the special cluster numbers * to be the same for all cluster sizes * to let the rest of msdosfs handle * all cases the same. */ if ((cn | ~pmp->pm_fatmask) >= CLUST_RSRVD) cn |= ~pmp->pm_fatmask; } if (!MSDOSFSEOF(pmp, cn)) { if (bp) brelse(bp); if (bnp) *bnp = cntobn(pmp, cn); if (cnp) *cnp = cn; fc_setcache(dep, FC_LASTMAP, i, cn); return (0); } hiteof:; if (cnp) *cnp = i; if (bp) brelse(bp); /* update last file cluster entry in the FAT cache */ fc_setcache(dep, FC_LASTFC, i - 1, prevcn); return (E2BIG); } /* * Find the closest entry in the FAT cache to the cluster we are looking * for. */ static void fc_lookup(struct denode *dep, u_long findcn, u_long *frcnp, u_long *fsrcnp) { int i; u_long cn; struct fatcache *closest = NULL; ASSERT_VOP_LOCKED(DETOV(dep), "fc_lookup"); for (i = 0; i < FC_SIZE; i++) { cn = dep->de_fc[i].fc_frcn; if (cn != FCE_EMPTY && cn <= findcn) { if (closest == NULL || cn > closest->fc_frcn) closest = &dep->de_fc[i]; } } if (closest) { *frcnp = closest->fc_frcn; *fsrcnp = closest->fc_fsrcn; } } /* * Purge the FAT cache in denode dep of all entries relating to file * relative cluster frcn and beyond. */ void fc_purge(struct denode *dep, u_int frcn) { int i; struct fatcache *fcp; ASSERT_VOP_ELOCKED(DETOV(dep), "fc_purge"); fcp = dep->de_fc; for (i = 0; i < FC_SIZE; i++, fcp++) { if (fcp->fc_frcn >= frcn) fcp->fc_frcn = FCE_EMPTY; } } /* * Update the FAT. * If mirroring the FAT, update all copies, with the first copy as last. * Else update only the current FAT (ignoring the others). * * pmp - msdosfsmount structure for filesystem to update * bp - addr of modified FAT block * fatbn - block number relative to begin of filesystem of the modified FAT block. */ static void updatefats(struct msdosfsmount *pmp, struct buf *bp, u_long fatbn) { struct buf *bpn; int cleanfat, i; #ifdef MSDOSFS_DEBUG printf("updatefats(pmp %p, bp %p, fatbn %lu)\n", pmp, bp, fatbn); #endif if (pmp->pm_flags & MSDOSFS_FATMIRROR) { /* * Now copy the block(s) of the modified FAT to the other copies of * the FAT and write them out. This is faster than reading in the * other FATs and then writing them back out. This could tie up * the FAT for quite a while. Preventing others from accessing it. * To prevent us from going after the FAT quite so much we use * delayed writes, unless they specified "synchronous" when the * filesystem was mounted. If synch is asked for then use * bwrite()'s and really slow things down. */ if (fatbn != pmp->pm_fatblk || FAT12(pmp)) cleanfat = 0; else if (FAT16(pmp)) cleanfat = 16; else cleanfat = 32; for (i = 1; i < pmp->pm_FATs; i++) { fatbn += pmp->pm_FATsecs; /* getblk() never fails */ bpn = getblk(pmp->pm_devvp, fatbn, bp->b_bcount, 0, 0, 0); memcpy(bpn->b_data, bp->b_data, bp->b_bcount); /* Force the clean bit on in the other copies. */ if (cleanfat == 16) ((uint8_t *)bpn->b_data)[3] |= 0x80; else if (cleanfat == 32) ((uint8_t *)bpn->b_data)[7] |= 0x08; if (pmp->pm_mountp->mnt_flag & MNT_SYNCHRONOUS) bwrite(bpn); else bdwrite(bpn); } } /* * Write out the first (or current) FAT last. */ if (pmp->pm_mountp->mnt_flag & MNT_SYNCHRONOUS) bwrite(bp); else bdwrite(bp); } /* * Updating entries in 12 bit FATs is a pain in the butt. * * The following picture shows where nibbles go when moving from a 12 bit * cluster number into the appropriate bytes in the FAT. * * byte m byte m+1 byte m+2 * +----+----+ +----+----+ +----+----+ * | 0 1 | | 2 3 | | 4 5 | FAT bytes * +----+----+ +----+----+ +----+----+ * * +----+----+----+ +----+----+----+ * | 3 0 1 | | 4 5 2 | * +----+----+----+ +----+----+----+ * cluster n cluster n+1 * * Where n is even. m = n + (n >> 2) * */ static __inline void usemap_alloc(struct msdosfsmount *pmp, u_long cn) { MSDOSFS_ASSERT_MP_LOCKED(pmp); KASSERT(cn <= pmp->pm_maxcluster, ("cn too large %lu %lu", cn, pmp->pm_maxcluster)); KASSERT((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0, ("usemap_alloc on ro msdosfs mount")); KASSERT((pmp->pm_inusemap[cn / N_INUSEBITS] & (1U << (cn % N_INUSEBITS))) == 0, ("Allocating used sector %ld %ld %x", cn, cn % N_INUSEBITS, (unsigned)pmp->pm_inusemap[cn / N_INUSEBITS])); pmp->pm_inusemap[cn / N_INUSEBITS] |= 1U << (cn % N_INUSEBITS); KASSERT(pmp->pm_freeclustercount > 0, ("usemap_alloc: too little")); pmp->pm_freeclustercount--; pmp->pm_flags |= MSDOSFS_FSIMOD; } static int usemap_free(struct msdosfsmount *pmp, u_long cn) { MSDOSFS_ASSERT_MP_LOCKED(pmp); KASSERT(cn <= pmp->pm_maxcluster, ("cn too large %lu %lu", cn, pmp->pm_maxcluster)); KASSERT((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0, ("usemap_free on ro msdosfs mount")); if ((pmp->pm_inusemap[cn / N_INUSEBITS] & (1U << (cn % N_INUSEBITS))) == 0) { printf("%s: Freeing unused sector %ld %ld %x\n", pmp->pm_mountp->mnt_stat.f_mntonname, cn, cn % N_INUSEBITS, (unsigned)pmp->pm_inusemap[cn / N_INUSEBITS]); + msdosfs_integrity_error(pmp); return (EINTEGRITY); } pmp->pm_freeclustercount++; pmp->pm_flags |= MSDOSFS_FSIMOD; pmp->pm_inusemap[cn / N_INUSEBITS] &= ~(1U << (cn % N_INUSEBITS)); return (0); } void clusterfree(struct msdosfsmount *pmp, u_long cluster) { int error; u_long oldcn; error = fatentry(FAT_GET_AND_SET, pmp, cluster, &oldcn, MSDOSFSFREE); if (error != 0) return; /* * If the cluster was successfully marked free, then update * the count of free clusters, and turn off the "allocated" * bit in the "in use" cluster bit map. */ MSDOSFS_LOCK_MP(pmp); error = usemap_free(pmp, cluster); MSDOSFS_UNLOCK_MP(pmp); } /* * Get or Set or 'Get and Set' the cluster'th entry in the FAT. * * function - whether to get or set a FAT entry * pmp - address of the msdosfsmount structure for the filesystem * whose FAT is to be manipulated. * cn - which cluster is of interest * oldcontents - address of a word that is to receive the contents of the * cluster'th entry if this is a get function * newcontents - the new value to be written into the cluster'th element of * the FAT if this is a set function. * * This function can also be used to free a cluster by setting the FAT entry * for a cluster to 0. * * All copies of the FAT are updated if this is a set function. NOTE: If * fatentry() marks a cluster as free it does not update the inusemap in * the msdosfsmount structure. This is left to the caller. */ int fatentry(int function, struct msdosfsmount *pmp, u_long cn, u_long *oldcontents, u_long newcontents) { int error; u_long readcn; u_long bn, bo, bsize, byteoffset; struct buf *bp; #ifdef MSDOSFS_DEBUG printf("fatentry(func %d, pmp %p, clust %lu, oldcon %p, newcon %lx)\n", function, pmp, cn, oldcontents, newcontents); #endif #ifdef DIAGNOSTIC /* * Be sure they asked us to do something. */ if ((function & (FAT_SET | FAT_GET)) == 0) { #ifdef MSDOSFS_DEBUG printf("fatentry(): function code doesn't specify get or set\n"); #endif return (EINVAL); } /* * If they asked us to return a cluster number but didn't tell us * where to put it, give them an error. */ if ((function & FAT_GET) && oldcontents == NULL) { #ifdef MSDOSFS_DEBUG printf("fatentry(): get function with no place to put result\n"); #endif return (EINVAL); } #endif /* * Be sure the requested cluster is in the filesystem. */ if (cn < CLUST_FIRST || cn > pmp->pm_maxcluster) return (EINVAL); byteoffset = FATOFS(pmp, cn); fatblock(pmp, byteoffset, &bn, &bsize, &bo); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) { return (error); } if (function & FAT_GET) { if (FAT32(pmp)) readcn = getulong(bp->b_data + bo); else readcn = getushort(bp->b_data + bo); if (FAT12(pmp) & (cn & 1)) readcn >>= 4; readcn &= pmp->pm_fatmask; /* map reserved FAT entries to same values for all FATs */ if ((readcn | ~pmp->pm_fatmask) >= CLUST_RSRVD) readcn |= ~pmp->pm_fatmask; *oldcontents = readcn; } if (function & FAT_SET) { switch (pmp->pm_fatmask) { case FAT12_MASK: readcn = getushort(bp->b_data + bo); if (cn & 1) { readcn &= 0x000f; readcn |= newcontents << 4; } else { readcn &= 0xf000; readcn |= newcontents & 0xfff; } putushort(bp->b_data + bo, readcn); break; case FAT16_MASK: putushort(bp->b_data + bo, newcontents); break; case FAT32_MASK: /* * According to spec we have to retain the * high order bits of the FAT entry. */ readcn = getulong(bp->b_data + bo); readcn &= ~FAT32_MASK; readcn |= newcontents & FAT32_MASK; putulong(bp->b_data + bo, readcn); break; } updatefats(pmp, bp, bn); bp = NULL; pmp->pm_fmod = 1; } if (bp) brelse(bp); return (0); } /* * Update a contiguous cluster chain * * pmp - mount point * start - first cluster of chain * count - number of clusters in chain * fillwith - what to write into FAT entry of last cluster */ static int fatchain(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith) { int error; u_long bn, bo, bsize, byteoffset, readcn, newc; struct buf *bp; #ifdef MSDOSFS_DEBUG printf("fatchain(pmp %p, start %lu, count %lu, fillwith %lx)\n", pmp, start, count, fillwith); #endif /* * Be sure the clusters are in the filesystem. */ if (start < CLUST_FIRST || start + count - 1 > pmp->pm_maxcluster) return (EINVAL); while (count > 0) { byteoffset = FATOFS(pmp, start); fatblock(pmp, byteoffset, &bn, &bsize, &bo); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) { return (error); } while (count > 0) { start++; newc = --count > 0 ? start : fillwith; switch (pmp->pm_fatmask) { case FAT12_MASK: readcn = getushort(bp->b_data + bo); if (start & 1) { readcn &= 0xf000; readcn |= newc & 0xfff; } else { readcn &= 0x000f; readcn |= newc << 4; } putushort(bp->b_data + bo, readcn); bo++; if (!(start & 1)) bo++; break; case FAT16_MASK: putushort(bp->b_data + bo, newc); bo += 2; break; case FAT32_MASK: readcn = getulong(bp->b_data + bo); readcn &= ~pmp->pm_fatmask; readcn |= newc & pmp->pm_fatmask; putulong(bp->b_data + bo, readcn); bo += 4; break; } if (bo >= bsize) break; } updatefats(pmp, bp, bn); } pmp->pm_fmod = 1; return (0); } /* * Check the length of a free cluster chain starting at start. * * pmp - mount point * start - start of chain * count - maximum interesting length */ static int chainlength(struct msdosfsmount *pmp, u_long start, u_long count) { u_long idx, max_idx; u_int map; u_long len; MSDOSFS_ASSERT_MP_LOCKED(pmp); if (start > pmp->pm_maxcluster) return (0); max_idx = pmp->pm_maxcluster / N_INUSEBITS; idx = start / N_INUSEBITS; start %= N_INUSEBITS; map = pmp->pm_inusemap[idx]; map &= ~((1U << start) - 1); if (map) { len = ffs(map) - 1 - start; len = MIN(len, count); if (start + len > pmp->pm_maxcluster) len = pmp->pm_maxcluster - start + 1; return (len); } len = N_INUSEBITS - start; if (len >= count) { len = count; if (start + len > pmp->pm_maxcluster) len = pmp->pm_maxcluster - start + 1; return (len); } while (++idx <= max_idx) { if (len >= count) break; map = pmp->pm_inusemap[idx]; if (map) { len += ffs(map) - 1; break; } len += N_INUSEBITS; } len = MIN(len, count); if (start + len > pmp->pm_maxcluster) len = pmp->pm_maxcluster - start + 1; return (len); } /* * Allocate contigous free clusters. * * pmp - mount point. * start - start of cluster chain. * count - number of clusters to allocate. * fillwith - put this value into the FAT entry for the * last allocated cluster. * retcluster - put the first allocated cluster's number here. * got - how many clusters were actually allocated. */ static int chainalloc(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got) { int error; u_long cl, n; MSDOSFS_ASSERT_MP_LOCKED(pmp); KASSERT((pmp->pm_flags & MSDOSFSMNT_RONLY) == 0, ("chainalloc on ro msdosfs mount")); for (cl = start, n = count; n-- > 0;) usemap_alloc(pmp, cl++); pmp->pm_nxtfree = start + count; if (pmp->pm_nxtfree > pmp->pm_maxcluster) pmp->pm_nxtfree = CLUST_FIRST; pmp->pm_flags |= MSDOSFS_FSIMOD; error = fatchain(pmp, start, count, fillwith); if (error != 0) { for (cl = start, n = count; n-- > 0;) (void)usemap_free(pmp, cl++); return (error); } #ifdef MSDOSFS_DEBUG printf("clusteralloc(): allocated cluster chain at %lu (%lu clusters)\n", start, count); #endif if (retcluster) *retcluster = start; if (got) *got = count; return (0); } /* * Allocate contiguous free clusters. * * pmp - mount point. * start - preferred start of cluster chain. * count - number of clusters requested. * fillwith - put this value into the FAT entry for the * last allocated cluster. * retcluster - put the first allocated cluster's number here. * got - how many clusters were actually allocated. */ int clusteralloc(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got) { int error; MSDOSFS_LOCK_MP(pmp); error = clusteralloc1(pmp, start, count, fillwith, retcluster, got); MSDOSFS_UNLOCK_MP(pmp); return (error); } static int clusteralloc1(struct msdosfsmount *pmp, u_long start, u_long count, u_long fillwith, u_long *retcluster, u_long *got) { u_long idx; u_long len, newst, foundl, cn, l; u_long foundcn = 0; /* XXX: foundcn could be used unititialized */ u_int map; MSDOSFS_ASSERT_MP_LOCKED(pmp); #ifdef MSDOSFS_DEBUG printf("clusteralloc(): find %lu clusters\n", count); #endif if (start) { if ((len = chainlength(pmp, start, count)) >= count) return (chainalloc(pmp, start, count, fillwith, retcluster, got)); } else len = 0; newst = pmp->pm_nxtfree; foundl = 0; for (cn = newst; cn <= pmp->pm_maxcluster;) { idx = cn / N_INUSEBITS; map = pmp->pm_inusemap[idx]; map |= (1U << (cn % N_INUSEBITS)) - 1; if (map != FULL_RUN) { cn = idx * N_INUSEBITS + ffs(map ^ FULL_RUN) - 1; if ((l = chainlength(pmp, cn, count)) >= count) return (chainalloc(pmp, cn, count, fillwith, retcluster, got)); if (l > foundl) { foundcn = cn; foundl = l; } cn += l + 1; continue; } cn += N_INUSEBITS - cn % N_INUSEBITS; } for (cn = 0; cn < newst;) { idx = cn / N_INUSEBITS; map = pmp->pm_inusemap[idx]; map |= (1U << (cn % N_INUSEBITS)) - 1; if (map != FULL_RUN) { cn = idx * N_INUSEBITS + ffs(map ^ FULL_RUN) - 1; if ((l = chainlength(pmp, cn, count)) >= count) return (chainalloc(pmp, cn, count, fillwith, retcluster, got)); if (l > foundl) { foundcn = cn; foundl = l; } cn += l + 1; continue; } cn += N_INUSEBITS - cn % N_INUSEBITS; } if (!foundl) return (ENOSPC); if (len) return (chainalloc(pmp, start, len, fillwith, retcluster, got)); else return (chainalloc(pmp, foundcn, foundl, fillwith, retcluster, got)); } /* * Free a chain of clusters. * * pmp - address of the msdosfs mount structure for the filesystem * containing the cluster chain to be freed. * startcluster - number of the 1st cluster in the chain of clusters to be * freed. */ int freeclusterchain(struct msdosfsmount *pmp, u_long cluster) { int error; struct buf *bp = NULL; u_long bn, bo, bsize, byteoffset; u_long readcn, lbn = -1; MSDOSFS_LOCK_MP(pmp); while (cluster >= CLUST_FIRST && cluster <= pmp->pm_maxcluster) { byteoffset = FATOFS(pmp, cluster); fatblock(pmp, byteoffset, &bn, &bsize, &bo); if (lbn != bn) { if (bp) updatefats(pmp, bp, lbn); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) { MSDOSFS_UNLOCK_MP(pmp); return (error); } lbn = bn; } error = usemap_free(pmp, cluster); if (error != 0) { updatefats(pmp, bp, lbn); MSDOSFS_UNLOCK_MP(pmp); return (error); } switch (pmp->pm_fatmask) { case FAT12_MASK: readcn = getushort(bp->b_data + bo); if (cluster & 1) { cluster = readcn >> 4; readcn &= 0x000f; readcn |= MSDOSFSFREE << 4; } else { cluster = readcn; readcn &= 0xf000; readcn |= MSDOSFSFREE & 0xfff; } putushort(bp->b_data + bo, readcn); break; case FAT16_MASK: cluster = getushort(bp->b_data + bo); putushort(bp->b_data + bo, MSDOSFSFREE); break; case FAT32_MASK: cluster = getulong(bp->b_data + bo); putulong(bp->b_data + bo, (MSDOSFSFREE & FAT32_MASK) | (cluster & ~FAT32_MASK)); break; } cluster &= pmp->pm_fatmask; if ((cluster | ~pmp->pm_fatmask) >= CLUST_RSRVD) cluster |= pmp->pm_fatmask; } if (bp) updatefats(pmp, bp, bn); MSDOSFS_UNLOCK_MP(pmp); return (0); } /* * Read in FAT blocks looking for free clusters. For every free cluster * found turn off its corresponding bit in the pm_inusemap. */ int fillinusemap(struct msdosfsmount *pmp) { struct buf *bp; u_long bn, bo, bsize, byteoffset, cn, readcn; int error; MSDOSFS_ASSERT_MP_LOCKED(pmp); bp = NULL; /* * Mark all clusters in use, we mark the free ones in the FAT scan * loop further down. */ for (cn = 0; cn < (pmp->pm_maxcluster + N_INUSEBITS) / N_INUSEBITS; cn++) pmp->pm_inusemap[cn] = FULL_RUN; /* * Figure how many free clusters are in the filesystem by ripping * through the FAT counting the number of entries whose content is * zero. These represent free clusters. */ pmp->pm_freeclustercount = 0; for (cn = 0; cn <= pmp->pm_maxcluster; cn++) { byteoffset = FATOFS(pmp, cn); bo = byteoffset % pmp->pm_fatblocksize; if (bo == 0) { /* Read new FAT block */ if (bp != NULL) brelse(bp); fatblock(pmp, byteoffset, &bn, &bsize, NULL); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error != 0) return (error); } if (FAT32(pmp)) readcn = getulong(bp->b_data + bo); else readcn = getushort(bp->b_data + bo); if (FAT12(pmp) && (cn & 1)) readcn >>= 4; readcn &= pmp->pm_fatmask; /* * Check if the FAT ID matches the BPB's media descriptor and * all other bits are set to 1. */ if (cn == 0 && readcn != ((pmp->pm_fatmask & 0xffffff00) | pmp->pm_bpb.bpbMedia)) { #ifdef MSDOSFS_DEBUG printf("mountmsdosfs(): Media descriptor in BPB" "does not match FAT ID\n"); #endif brelse(bp); return (EINVAL); } else if (readcn == CLUST_FREE) { error = usemap_free(pmp, cn); if (error != 0) { brelse(bp); return (error); } } } if (bp != NULL) brelse(bp); for (cn = pmp->pm_maxcluster + 1; cn < (pmp->pm_maxcluster + N_INUSEBITS) / N_INUSEBITS; cn++) pmp->pm_inusemap[cn / N_INUSEBITS] |= 1U << (cn % N_INUSEBITS); return (0); } /* * Allocate a new cluster and chain it onto the end of the file. * * dep - the file to extend * count - number of clusters to allocate * bpp - where to return the address of the buf header for the first new * file block * ncp - where to put cluster number of the first newly allocated cluster * If this pointer is 0, do not return the cluster number. * flags - see fat.h * * NOTE: This function is not responsible for turning on the DE_UPDATE bit of * the de_flag field of the denode and it does not change the de_FileSize * field. This is left for the caller to do. */ int extendfile(struct denode *dep, u_long count, struct buf **bpp, u_long *ncp, int flags) { int error; u_long frcn; u_long cn, got; struct msdosfsmount *pmp = dep->de_pmp; struct buf *bp; daddr_t blkno; /* * Don't try to extend the root directory */ if (dep->de_StartCluster == MSDOSFSROOT && (dep->de_Attributes & ATTR_DIRECTORY)) { #ifdef MSDOSFS_DEBUG printf("extendfile(): attempt to extend root directory\n"); #endif return (ENOSPC); } /* * If the "file's last cluster" cache entry is empty, and the file * is not empty, then fill the cache entry by calling pcbmap(). */ if (dep->de_fc[FC_LASTFC].fc_frcn == FCE_EMPTY && dep->de_StartCluster != 0) { error = pcbmap(dep, 0xffff, 0, &cn, 0); /* we expect it to return E2BIG */ if (error != E2BIG) return (error); } dep->de_fc[FC_NEXTTOLASTFC].fc_frcn = dep->de_fc[FC_LASTFC].fc_frcn; dep->de_fc[FC_NEXTTOLASTFC].fc_fsrcn = dep->de_fc[FC_LASTFC].fc_fsrcn; while (count > 0) { /* * Allocate a new cluster chain and cat onto the end of the * file. If the file is empty we make de_StartCluster point * to the new block. Note that de_StartCluster being 0 is * sufficient to be sure the file is empty since we exclude * attempts to extend the root directory above, and the root * dir is the only file with a startcluster of 0 that has * blocks allocated (sort of). */ if (dep->de_StartCluster == 0) cn = 0; else cn = dep->de_fc[FC_LASTFC].fc_fsrcn + 1; error = clusteralloc(pmp, cn, count, CLUST_EOFE, &cn, &got); if (error) return (error); count -= got; /* * Give them the filesystem relative cluster number if they want * it. */ if (ncp) { *ncp = cn; ncp = NULL; } if (dep->de_StartCluster == 0) { dep->de_StartCluster = cn; frcn = 0; } else { error = fatentry(FAT_SET, pmp, dep->de_fc[FC_LASTFC].fc_fsrcn, 0, cn); if (error) { clusterfree(pmp, cn); return (error); } frcn = dep->de_fc[FC_LASTFC].fc_frcn + 1; } /* * Update the "last cluster of the file" entry in the * denode's FAT cache. */ fc_setcache(dep, FC_LASTFC, frcn + got - 1, cn + got - 1); if (flags & DE_CLEAR) { while (got-- > 0) { /* * Get the buf header for the new block of the file. */ if (dep->de_Attributes & ATTR_DIRECTORY) bp = getblk(pmp->pm_devvp, cntobn(pmp, cn++), pmp->pm_bpcluster, 0, 0, 0); else { bp = getblk(DETOV(dep), frcn++, pmp->pm_bpcluster, 0, 0, 0); /* * Do the bmap now, as in msdosfs_write */ if (pcbmap(dep, bp->b_lblkno, &blkno, 0, 0)) bp->b_blkno = -1; if (bp->b_blkno == -1) panic("extendfile: pcbmap"); else bp->b_blkno = blkno; } clrbuf(bp); if (bpp) { *bpp = bp; bpp = NULL; } else { bdwrite(bp); } if (vm_page_count_severe() || buf_dirty_count_severe()) vn_fsync_buf(DETOV(dep), MNT_WAIT); } } } return (0); } /*- * Routine to mark a FAT16 or FAT32 volume as "clean" or "dirty" by * manipulating the upper bit of the FAT entry for cluster 1. Note that * this bit is not defined for FAT12 volumes, which are always assumed to * be clean. * * The fatentry() routine only works on cluster numbers that a file could * occupy, so it won't manipulate the entry for cluster 1. So we have to do * it here. The code was stolen from fatentry() and tailored for cluster 1. * * Inputs: * pmp The MS-DOS volume to mark * dirty Non-zero if the volume should be marked dirty; zero if it * should be marked clean * * Result: * 0 Success * EROFS Volume is read-only * ? (other errors from called routines) */ int markvoldirty_upgrade(struct msdosfsmount *pmp, bool dirty, bool rw_upgrade) { struct buf *bp; u_long bn, bo, bsize, byteoffset, fatval; int error; /* * FAT12 does not support a "clean" bit, so don't do anything for * FAT12. */ if (FAT12(pmp)) return (0); /* * Can't change the bit on a read-only filesystem, except as part of * ro->rw upgrade. */ if ((pmp->pm_flags & MSDOSFSMNT_RONLY) != 0 && !rw_upgrade) return (EROFS); /* * Fetch the block containing the FAT entry. It is given by the * pseudo-cluster 1. */ byteoffset = FATOFS(pmp, 1); fatblock(pmp, byteoffset, &bn, &bsize, &bo); error = bread(pmp->pm_devvp, bn, bsize, NOCRED, &bp); if (error) return (error); /* * Get the current value of the FAT entry and set/clear the relevant * bit. Dirty means clear the "clean" bit; clean means set the * "clean" bit. */ if (FAT32(pmp)) { /* FAT32 uses bit 27. */ fatval = getulong(&bp->b_data[bo]); if (dirty) fatval &= 0xF7FFFFFF; else fatval |= 0x08000000; putulong(&bp->b_data[bo], fatval); } else { /* Must be FAT16; use bit 15. */ fatval = getushort(&bp->b_data[bo]); if (dirty) fatval &= 0x7FFF; else fatval |= 0x8000; putushort(&bp->b_data[bo], fatval); } /* * The concern here is that a devvp may be readonly, without reporting * itself as such through the usual channels. In that case, we'd like * it if attempting to mount msdosfs rw didn't panic the system. * * markvoldirty is invoked as the first write on backing devvps when * either msdosfs is mounted for the first time, or a ro mount is * upgraded to rw. * * In either event, if a write error occurs dirtying the volume: * - No user data has been permitted to be written to cache yet. * - We can abort the high-level operation (mount, or ro->rw) safely. * - We don't derive any benefit from leaving a zombie dirty buf in * the cache that can not be cleaned or evicted. * * So, mark B_INVALONERR to have bwrite() -> brelse() detect that * condition and force-invalidate our write to the block if it occurs. * * PR 210316 provides more context on the discovery and diagnosis of * the problem, as well as earlier attempts to solve it. */ bp->b_flags |= B_INVALONERR; /* Write out the modified FAT block synchronously. */ return (bwrite(bp)); } diff --git a/sys/fs/msdosfs/msdosfs_lookup.c b/sys/fs/msdosfs/msdosfs_lookup.c index 3db9665f6094..91b778b8173b 100644 --- a/sys/fs/msdosfs/msdosfs_lookup.c +++ b/sys/fs/msdosfs/msdosfs_lookup.c @@ -1,1096 +1,1100 @@ /* $FreeBSD$ */ /* $NetBSD: msdosfs_lookup.c,v 1.37 1997/11/17 15:36:54 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 static int msdosfs_lookup_checker(struct msdosfsmount *pmp, struct vnode *dvp, struct denode *tdp, struct vnode **vpp) { struct vnode *vp; vp = DETOV(tdp); /* * Lookup assumes that directory cannot be hardlinked. * Corrupted msdosfs filesystem could break this assumption. */ if (vp == dvp) { vput(vp); + msdosfs_integrity_error(pmp); *vpp = NULL; return (EBADF); } *vpp = vp; return (0); } int msdosfs_lookup(struct vop_cachedlookup_args *ap) { return (msdosfs_lookup_ino(ap->a_dvp, ap->a_vpp, ap->a_cnp, NULL, NULL)); } struct deget_dotdot { u_long cluster; int blkoff; }; static int msdosfs_deget_dotdot(struct mount *mp, void *arg, int lkflags, struct vnode **rvp) { struct deget_dotdot *dd_arg; struct denode *rdp; struct msdosfsmount *pmp; int error; pmp = VFSTOMSDOSFS(mp); dd_arg = arg; error = deget(pmp, dd_arg->cluster, dd_arg->blkoff, LK_EXCLUSIVE, &rdp); if (error == 0) *rvp = DETOV(rdp); return (error); } /* * When we search a directory the blocks containing directory entries are * read and examined. The directory entries contain information that would * normally be in the inode of a unix filesystem. This means that some of * a directory's contents may also be in memory resident denodes (sort of * an inode). This can cause problems if we are searching while some other * process is modifying a directory. To prevent one process from accessing * incompletely modified directory information we depend upon being the * sole owner of a directory block. bread/brelse provide this service. * This being the case, when a process modifies a directory it must first * acquire the disk block that contains the directory entry to be modified. * Then update the disk block and the denode, and then write the disk block * out to disk. This way disk blocks containing directory entries and in * memory denode's will be in synch. */ int msdosfs_lookup_ino(struct vnode *vdp, struct vnode **vpp, struct componentname *cnp, daddr_t *scnp, u_long *blkoffp) { struct mbnambuf nb; daddr_t bn; int error; int slotcount; int slotoffset = 0; int frcn; u_long cluster; u_long blkoff; int diroff; int blsize; int isadir; /* ~0 if found direntry is a directory */ daddr_t scn; /* starting cluster number */ struct vnode *pdp; struct denode *dp; struct denode *tdp; struct msdosfsmount *pmp; struct buf *bp = NULL; struct direntry *dep = NULL; struct deget_dotdot dd_arg; u_char dosfilename[12]; int flags = cnp->cn_flags; int nameiop = cnp->cn_nameiop; int unlen; uint64_t inode1; int wincnt = 1; int chksum = -1, chksum_ok; int olddos = 1; #ifdef MSDOSFS_DEBUG printf("msdosfs_lookup(): looking for %s\n", cnp->cn_nameptr); #endif dp = VTODE(vdp); pmp = dp->de_pmp; #ifdef MSDOSFS_DEBUG printf("msdosfs_lookup(): vdp %p, dp %p, Attr %02x\n", vdp, dp, dp->de_Attributes); #endif restart: if (vpp != NULL) *vpp = NULL; /* * If they are going after the . or .. entry in the root directory, * they won't find it. DOS filesystems don't have them in the root * directory. So, we fake it. deget() is in on this scam too. */ if ((vdp->v_vflag & VV_ROOT) && cnp->cn_nameptr[0] == '.' && (cnp->cn_namelen == 1 || (cnp->cn_namelen == 2 && cnp->cn_nameptr[1] == '.'))) { isadir = ATTR_DIRECTORY; scn = MSDOSFSROOT; #ifdef MSDOSFS_DEBUG printf("msdosfs_lookup(): looking for . or .. in root directory\n"); #endif cluster = MSDOSFSROOT; blkoff = MSDOSFSROOT_OFS; goto foundroot; } switch (unix2dosfn((const u_char *)cnp->cn_nameptr, dosfilename, cnp->cn_namelen, 0, pmp)) { case 0: return (EINVAL); case 1: break; case 2: wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr, cnp->cn_namelen, pmp) + 1; break; case 3: olddos = 0; wincnt = winSlotCnt((const u_char *)cnp->cn_nameptr, cnp->cn_namelen, pmp) + 1; break; } if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME) { wincnt = 1; olddos = 1; } unlen = winLenFixup(cnp->cn_nameptr, cnp->cn_namelen); /* * Suppress search for slots unless creating * file and at end of pathname, in which case * we watch for a place to put the new file in * case it doesn't already exist. */ slotcount = wincnt; if ((nameiop == CREATE || nameiop == RENAME) && (flags & ISLASTCN)) slotcount = 0; #ifdef MSDOSFS_DEBUG printf("msdosfs_lookup(): dos version of filename %s, length %ld\n", dosfilename, cnp->cn_namelen); #endif /* * Search the directory pointed at by vdp for the name pointed at * by cnp->cn_nameptr. */ tdp = NULL; mbnambuf_init(&nb); /* * The outer loop ranges over the clusters that make up the * directory. Note that the root directory is different from all * other directories. It has a fixed number of blocks that are not * part of the pool of allocatable clusters. So, we treat it a * little differently. The root directory starts at "cluster" 0. */ diroff = 0; for (frcn = 0;; frcn++) { error = pcbmap(dp, frcn, &bn, &cluster, &blsize); if (error) { if (error == E2BIG) break; return (error); } error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp); if (error) { return (error); } for (blkoff = 0; blkoff < blsize; blkoff += sizeof(struct direntry), diroff += sizeof(struct direntry)) { dep = (struct direntry *)(bp->b_data + blkoff); /* * If the slot is empty and we are still looking * for an empty then remember this one. If the * slot is not empty then check to see if it * matches what we are looking for. If the slot * has never been filled with anything, then the * remainder of the directory has never been used, * so there is no point in searching it. */ if (dep->deName[0] == SLOT_EMPTY || dep->deName[0] == SLOT_DELETED) { /* * Drop memory of previous long matches */ chksum = -1; mbnambuf_init(&nb); if (slotcount < wincnt) { slotcount++; slotoffset = diroff; } if (dep->deName[0] == SLOT_EMPTY) { brelse(bp); goto notfound; } } else { /* * If there wasn't enough space for our winentries, * forget about the empty space */ if (slotcount < wincnt) slotcount = 0; /* * Check for Win95 long filename entry */ if (dep->deAttributes == ATTR_WIN95) { if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME) continue; chksum = win2unixfn(&nb, (struct winentry *)dep, chksum, pmp); continue; } chksum = winChkName(&nb, (const u_char *)cnp->cn_nameptr, unlen, chksum, pmp); if (chksum == -2) { chksum = -1; continue; } /* * Ignore volume labels (anywhere, not just * the root directory). */ if (dep->deAttributes & ATTR_VOLUME) { chksum = -1; continue; } /* * Check for a checksum or name match */ chksum_ok = (chksum == winChksum(dep->deName)); if (!chksum_ok && (!olddos || bcmp(dosfilename, dep->deName, 11))) { chksum = -1; continue; } #ifdef MSDOSFS_DEBUG printf("msdosfs_lookup(): match blkoff %d, diroff %d\n", blkoff, diroff); #endif /* * Remember where this directory * entry came from for whoever did * this lookup. */ dp->de_fndoffset = diroff; if (chksum_ok && nameiop == RENAME) { /* * Target had correct long name * directory entries, reuse them * as needed. */ dp->de_fndcnt = wincnt - 1; } else { /* * Long name directory entries * not present or corrupt, can only * reuse dos directory entry. */ dp->de_fndcnt = 0; } goto found; } } /* for (blkoff = 0; .... */ /* * Release the buffer holding the directory cluster just * searched. */ brelse(bp); } /* for (frcn = 0; ; frcn++) */ notfound: /* * We hold no disk buffers at this point. */ /* * Fixup the slot description to point to the place where * we might put the new DOS direntry (putting the Win95 * long name entries before that) */ if (!slotcount) { slotcount = 1; slotoffset = diroff; } if (wincnt > slotcount) slotoffset += sizeof(struct direntry) * (wincnt - slotcount); /* * If we get here we didn't find the entry we were looking for. But * that's ok if we are creating or renaming and are at the end of * the pathname and the directory hasn't been removed. */ #ifdef MSDOSFS_DEBUG printf("msdosfs_lookup(): op %d, refcnt %ld\n", nameiop, dp->de_refcnt); printf(" slotcount %d, slotoffset %d\n", slotcount, slotoffset); #endif if ((nameiop == CREATE || nameiop == RENAME) && (flags & ISLASTCN) && dp->de_refcnt != 0) { /* * Access for write is interpreted as allowing * creation of files in the directory. */ error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred, curthread); if (error) return (error); /* * Return an indication of where the new directory * entry should be put. */ dp->de_fndoffset = slotoffset; dp->de_fndcnt = wincnt - 1; /* * We return with the directory locked, so that * the parameters we set up above will still be * valid if we actually decide to do a direnter(). * We return ni_vp == NULL to indicate that the entry * does not currently exist; we leave a pointer to * the (locked) directory inode in ndp->ni_dvp. * The pathname buffer is saved so that the name * can be obtained later. * * NB - if the directory is unlocked, then this * information cannot be used. */ cnp->cn_flags |= SAVENAME; return (EJUSTRETURN); } #if 0 /* * Insert name into cache (as non-existent) if appropriate. * * XXX Negative caching is broken for msdosfs because the name * cache doesn't understand peculiarities such as case insensitivity * and 8.3 filenames. Hence, it may not invalidate all negative * entries if a file with this name is later created. */ if ((cnp->cn_flags & MAKEENTRY) != 0) cache_enter(vdp, *vpp, cnp); #endif return (ENOENT); found: /* * NOTE: We still have the buffer with matched directory entry at * this point. */ isadir = dep->deAttributes & ATTR_DIRECTORY; scn = getushort(dep->deStartCluster); if (FAT32(pmp)) { scn |= getushort(dep->deHighClust) << 16; if (scn == pmp->pm_rootdirblk) { /* * There should actually be 0 here. * Just ignore the error. */ scn = MSDOSFSROOT; } } if (isadir) { cluster = scn; if (cluster == MSDOSFSROOT) blkoff = MSDOSFSROOT_OFS; else blkoff = 0; } else if (cluster == MSDOSFSROOT) blkoff = diroff; /* * Now release buf to allow deget to read the entry again. * Reserving it here and giving it to deget could result * in a deadlock. */ brelse(bp); bp = NULL; foundroot: /* * If we entered at foundroot, then we are looking for the . or .. * entry of the filesystems root directory. isadir and scn were * setup before jumping here. And, bp is already null. */ if (FAT32(pmp) && scn == MSDOSFSROOT) scn = pmp->pm_rootdirblk; if (scnp != NULL) { *scnp = cluster; *blkoffp = blkoff; return (0); } /* * If deleting, and at end of pathname, return * parameters which can be used to remove file. */ if (nameiop == DELETE && (flags & ISLASTCN)) { /* * Don't allow deleting the root. */ if (blkoff == MSDOSFSROOT_OFS) return (EBUSY); /* * Write access to directory required to delete files. */ error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred, curthread); if (error) return (error); /* * Return pointer to current entry in dp->i_offset. * Save directory inode pointer in ndp->ni_dvp for dirremove(). */ if (dp->de_StartCluster == scn && isadir) { /* "." */ VREF(vdp); *vpp = vdp; return (0); } error = deget(pmp, cluster, blkoff, LK_EXCLUSIVE, &tdp); if (error) return (error); return (msdosfs_lookup_checker(pmp, vdp, tdp, vpp)); } /* * If rewriting (RENAME), return the inode and the * information required to rewrite the present directory * Must get inode of directory entry to verify it's a * regular file, or empty directory. */ if (nameiop == RENAME && (flags & ISLASTCN)) { if (blkoff == MSDOSFSROOT_OFS) return (EBUSY); error = VOP_ACCESS(vdp, VWRITE, cnp->cn_cred, curthread); if (error) return (error); /* * Careful about locking second inode. * This can only occur if the target is ".". */ if (dp->de_StartCluster == scn && isadir) return (EISDIR); if ((error = deget(pmp, cluster, blkoff, LK_EXCLUSIVE, &tdp)) != 0) return (error); if ((error = msdosfs_lookup_checker(pmp, vdp, tdp, vpp)) != 0) return (error); cnp->cn_flags |= SAVENAME; return (0); } /* * Step through the translation in the name. We do not `vput' the * directory because we may need it again if a symbolic link * is relative to the current directory. Instead we save it * unlocked as "pdp". We must get the target inode before unlocking * the directory to insure that the inode will not be removed * before we get it. We prevent deadlock by always fetching * inodes from the root, moving down the directory tree. Thus * when following backward pointers ".." we must unlock the * parent directory before getting the requested directory. */ pdp = vdp; if (flags & ISDOTDOT) { dd_arg.cluster = cluster; dd_arg.blkoff = blkoff; error = vn_vget_ino_gen(vdp, msdosfs_deget_dotdot, &dd_arg, cnp->cn_lkflags, vpp); if (error != 0) { *vpp = NULL; return (error); } /* * Recheck that ".." still points to the inode we * looked up before pdp lock was dropped. */ error = msdosfs_lookup_ino(pdp, NULL, cnp, &scn, &blkoff); if (error) { vput(*vpp); *vpp = NULL; return (error); } if (FAT32(pmp) && scn == MSDOSFSROOT) scn = pmp->pm_rootdirblk; inode1 = scn * pmp->pm_bpcluster + blkoff; if (VTODE(*vpp)->de_inode != inode1) { vput(*vpp); goto restart; } - return (msdosfs_lookup_checker(pmp, vdp, VTODE(*vpp), vpp)); + error = msdosfs_lookup_checker(pmp, vdp, VTODE(*vpp), vpp); + if (error != 0) + return (error); } else if (dp->de_StartCluster == scn && isadir) { if (cnp->cn_namelen != 1 || cnp->cn_nameptr[0] != '.') { /* fs is corrupted, non-dot lookup returned dvp */ + msdosfs_integrity_error(pmp); return (EBADF); } VREF(vdp); /* we want ourself, ie "." */ *vpp = vdp; } else { if ((error = deget(pmp, cluster, blkoff, LK_EXCLUSIVE, &tdp)) != 0) return (error); if ((error = msdosfs_lookup_checker(pmp, vdp, tdp, vpp)) != 0) return (error); } /* * Insert name into cache if appropriate. */ if (cnp->cn_flags & MAKEENTRY) cache_enter(vdp, *vpp, cnp); return (0); } /* * dep - directory entry to copy into the directory * ddep - directory to add to * depp - return the address of the denode for the created directory entry * if depp != 0 * cnp - componentname needed for Win95 long filenames */ int createde(struct denode *dep, struct denode *ddep, struct denode **depp, struct componentname *cnp) { int error; u_long dirclust, diroffset; struct direntry *ndep; struct msdosfsmount *pmp = ddep->de_pmp; struct buf *bp; daddr_t bn; int blsize; #ifdef MSDOSFS_DEBUG printf("createde(dep %p, ddep %p, depp %p, cnp %p)\n", dep, ddep, depp, cnp); #endif /* * If no space left in the directory then allocate another cluster * and chain it onto the end of the file. There is one exception * to this. That is, if the root directory has no more space it * can NOT be expanded. extendfile() checks for and fails attempts * to extend the root directory. We just return an error in that * case. */ if (ddep->de_fndoffset >= ddep->de_FileSize) { diroffset = ddep->de_fndoffset + sizeof(struct direntry) - ddep->de_FileSize; dirclust = de_clcount(pmp, diroffset); error = extendfile(ddep, dirclust, 0, 0, DE_CLEAR); if (error) { (void)detrunc(ddep, ddep->de_FileSize, 0, NOCRED); return error; } /* * Update the size of the directory */ ddep->de_FileSize += de_cn2off(pmp, dirclust); } /* * We just read in the cluster with space. Copy the new directory * entry in. Then write it to disk. NOTE: DOS directories * do not get smaller as clusters are emptied. */ error = pcbmap(ddep, de_cluster(pmp, ddep->de_fndoffset), &bn, &dirclust, &blsize); if (error) return error; diroffset = ddep->de_fndoffset; if (dirclust != MSDOSFSROOT) diroffset &= pmp->pm_crbomask; if ((error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp)) != 0) { brelse(bp); return error; } ndep = bptoep(pmp, bp, ddep->de_fndoffset); DE_EXTERNALIZE(ndep, dep); /* * Now write the Win95 long name */ if (ddep->de_fndcnt > 0) { uint8_t chksum = winChksum(ndep->deName); const u_char *un = (const u_char *)cnp->cn_nameptr; int unlen = cnp->cn_namelen; int cnt = 1; while (--ddep->de_fndcnt >= 0) { if (!(ddep->de_fndoffset & pmp->pm_crbomask)) { if (DOINGASYNC(DETOV(ddep))) bdwrite(bp); else if ((error = bwrite(bp)) != 0) return error; ddep->de_fndoffset -= sizeof(struct direntry); error = pcbmap(ddep, de_cluster(pmp, ddep->de_fndoffset), &bn, 0, &blsize); if (error) return error; error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp); if (error) { return error; } ndep = bptoep(pmp, bp, ddep->de_fndoffset); } else { ndep--; ddep->de_fndoffset -= sizeof(struct direntry); } if (!unix2winfn(un, unlen, (struct winentry *)ndep, cnt++, chksum, pmp)) break; } } if (DOINGASYNC(DETOV(ddep))) bdwrite(bp); else if ((error = bwrite(bp)) != 0) return error; /* * If they want us to return with the denode gotten. */ if (depp) { if (dep->de_Attributes & ATTR_DIRECTORY) { dirclust = dep->de_StartCluster; if (FAT32(pmp) && dirclust == pmp->pm_rootdirblk) dirclust = MSDOSFSROOT; if (dirclust == MSDOSFSROOT) diroffset = MSDOSFSROOT_OFS; else diroffset = 0; } return (deget(pmp, dirclust, diroffset, LK_EXCLUSIVE, depp)); } return 0; } /* * Be sure a directory is empty except for "." and "..". Return 1 if empty, * return 0 if not empty or error. */ int dosdirempty(struct denode *dep) { int blsize; int error; u_long cn; daddr_t bn; struct buf *bp; struct msdosfsmount *pmp = dep->de_pmp; struct direntry *dentp; /* * Since the filesize field in directory entries for a directory is * zero, we just have to feel our way through the directory until * we hit end of file. */ for (cn = 0;; cn++) { if ((error = pcbmap(dep, cn, &bn, 0, &blsize)) != 0) { if (error == E2BIG) return (1); /* it's empty */ return (0); } error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp); if (error) { return (0); } for (dentp = (struct direntry *)bp->b_data; (char *)dentp < bp->b_data + blsize; dentp++) { if (dentp->deName[0] != SLOT_DELETED && (dentp->deAttributes & ATTR_VOLUME) == 0) { /* * In dos directories an entry whose name * starts with SLOT_EMPTY (0) starts the * beginning of the unused part of the * directory, so we can just return that it * is empty. */ if (dentp->deName[0] == SLOT_EMPTY) { brelse(bp); return (1); } /* * Any names other than "." and ".." in a * directory mean it is not empty. */ if (bcmp(dentp->deName, ". ", 11) && bcmp(dentp->deName, ".. ", 11)) { brelse(bp); #ifdef MSDOSFS_DEBUG printf("dosdirempty(): entry found %02x, %02x\n", dentp->deName[0], dentp->deName[1]); #endif return (0); /* not empty */ } } } brelse(bp); } /* NOTREACHED */ } /* * Check to see if the directory described by target is in some * subdirectory of source. This prevents something like the following from * succeeding and leaving a bunch or files and directories orphaned. mv * /a/b/c /a/b/c/d/e/f Where c and f are directories. * * source - the inode for /a/b/c * target - the inode for /a/b/c/d/e/f * * Returns 0 if target is NOT a subdirectory of source. * Otherwise returns a non-zero error number. */ int doscheckpath(struct denode *source, struct denode *target, daddr_t *wait_scn) { daddr_t scn; struct msdosfsmount *pmp; struct direntry *ep; struct denode *dep; struct buf *bp = NULL; int error = 0; *wait_scn = 0; pmp = target->de_pmp; lockmgr_assert(&pmp->pm_checkpath_lock, KA_XLOCKED); KASSERT(pmp == source->de_pmp, ("doscheckpath: source and target on different filesystems")); if ((target->de_Attributes & ATTR_DIRECTORY) == 0 || (source->de_Attributes & ATTR_DIRECTORY) == 0) return (ENOTDIR); if (target->de_StartCluster == source->de_StartCluster) return (EEXIST); if (target->de_StartCluster == MSDOSFSROOT || (FAT32(pmp) && target->de_StartCluster == pmp->pm_rootdirblk)) return (0); dep = target; vget(DETOV(dep), LK_EXCLUSIVE); for (;;) { if ((dep->de_Attributes & ATTR_DIRECTORY) == 0) { error = ENOTDIR; break; } scn = dep->de_StartCluster; error = bread(pmp->pm_devvp, cntobn(pmp, scn), pmp->pm_bpcluster, NOCRED, &bp); if (error != 0) break; ep = (struct direntry *)bp->b_data + 1; if ((ep->deAttributes & ATTR_DIRECTORY) == 0 || bcmp(ep->deName, ".. ", 11) != 0) { error = ENOTDIR; brelse(bp); break; } scn = getushort(ep->deStartCluster); if (FAT32(pmp)) scn |= getushort(ep->deHighClust) << 16; brelse(bp); if (scn == source->de_StartCluster) { error = EINVAL; break; } if (scn == MSDOSFSROOT) break; if (FAT32(pmp) && scn == pmp->pm_rootdirblk) { /* * scn should be 0 in this case, * but we silently ignore the error. */ break; } vput(DETOV(dep)); dep = NULL; /* NOTE: deget() clears dep on error */ error = deget(pmp, scn, 0, LK_EXCLUSIVE | LK_NOWAIT, &dep); if (error != 0) { *wait_scn = scn; break; } } #ifdef MSDOSFS_DEBUG if (error == ENOTDIR) printf("doscheckpath(): .. not a directory?\n"); #endif if (dep != NULL) vput(DETOV(dep)); return (error); } /* * Read in the disk block containing the directory entry (dirclu, dirofs) * and return the address of the buf header, and the address of the * directory entry within the block. */ int readep(struct msdosfsmount *pmp, u_long dirclust, u_long diroffset, struct buf **bpp, struct direntry **epp) { int error; daddr_t bn; int blsize; blsize = pmp->pm_bpcluster; if (dirclust == MSDOSFSROOT && de_blk(pmp, diroffset + blsize) > pmp->pm_rootdirsize) blsize = de_bn2off(pmp, pmp->pm_rootdirsize) & pmp->pm_crbomask; bn = detobn(pmp, dirclust, diroffset); if ((error = bread(pmp->pm_devvp, bn, blsize, NOCRED, bpp)) != 0) { brelse(*bpp); *bpp = NULL; return (error); } if (epp) *epp = bptoep(pmp, *bpp, diroffset); return (0); } /* * Read in the disk block containing the directory entry dep came from and * return the address of the buf header, and the address of the directory * entry within the block. */ int readde(struct denode *dep, struct buf **bpp, struct direntry **epp) { return (readep(dep->de_pmp, dep->de_dirclust, dep->de_diroffset, bpp, epp)); } /* * Remove a directory entry. At this point the file represented by the * directory entry to be removed is still full length until no one has it * open. When the file no longer being used msdosfs_inactive() is called * and will truncate the file to 0 length. When the vnode containing the * denode is needed for some other purpose by VFS it will call * msdosfs_reclaim() which will remove the denode from the denode cache. * * pdep directory where the entry is removed * dep file to be removed */ int removede(struct denode *pdep, struct denode *dep) { int error; struct direntry *ep; struct buf *bp; daddr_t bn; int blsize; struct msdosfsmount *pmp = pdep->de_pmp; u_long offset = pdep->de_fndoffset; #ifdef MSDOSFS_DEBUG printf("removede(): filename %s, dep %p, offset %08lx\n", dep->de_Name, dep, offset); #endif dep->de_refcnt--; offset += sizeof(struct direntry); do { offset -= sizeof(struct direntry); error = pcbmap(pdep, de_cluster(pmp, offset), &bn, 0, &blsize); if (error) return error; error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp); if (error) { return error; } ep = bptoep(pmp, bp, offset); /* * Check whether, if we came here the second time, i.e. * when underflowing into the previous block, the last * entry in this block is a longfilename entry, too. */ if (ep->deAttributes != ATTR_WIN95 && offset != pdep->de_fndoffset) { brelse(bp); break; } offset += sizeof(struct direntry); while (1) { /* * We are a bit aggressive here in that we delete any Win95 * entries preceding this entry, not just the ones we "own". * Since these presumably aren't valid anyway, * there should be no harm. */ offset -= sizeof(struct direntry); ep--->deName[0] = SLOT_DELETED; if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95) || !(offset & pmp->pm_crbomask) || ep->deAttributes != ATTR_WIN95) break; } if (DOINGASYNC(DETOV(pdep))) bdwrite(bp); else if ((error = bwrite(bp)) != 0) return error; } while (!(pmp->pm_flags & MSDOSFSMNT_NOWIN95) && !(offset & pmp->pm_crbomask) && offset); return 0; } /* * Create a unique DOS name in dvp */ int uniqdosname(struct denode *dep, struct componentname *cnp, u_char *cp) { struct msdosfsmount *pmp = dep->de_pmp; struct direntry *dentp; int gen; int blsize; u_long cn; daddr_t bn; struct buf *bp; int error; if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME) return (unix2dosfn((const u_char *)cnp->cn_nameptr, cp, cnp->cn_namelen, 0, pmp) ? 0 : EINVAL); for (gen = 1;; gen++) { /* * Generate DOS name with generation number */ if (!unix2dosfn((const u_char *)cnp->cn_nameptr, cp, cnp->cn_namelen, gen, pmp)) return gen == 1 ? EINVAL : EEXIST; /* * Now look for a dir entry with this exact name */ for (cn = error = 0; !error; cn++) { if ((error = pcbmap(dep, cn, &bn, 0, &blsize)) != 0) { if (error == E2BIG) /* EOF reached and not found */ return 0; return error; } error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp); if (error) { return error; } for (dentp = (struct direntry *)bp->b_data; (char *)dentp < bp->b_data + blsize; dentp++) { if (dentp->deName[0] == SLOT_EMPTY) { /* * Last used entry and not found */ brelse(bp); return 0; } /* * Ignore volume labels and Win95 entries */ if (dentp->deAttributes & ATTR_VOLUME) continue; if (!bcmp(dentp->deName, cp, 11)) { error = EEXIST; break; } } brelse(bp); } } }