/* $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, lkflags, 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 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 = DETOI(pmp, dirclust, diroffset); error = vfs_hash_get(mntp, inode, lkflags, curthread, &nvp, de_vncmpf, &inode); #ifdef MSDOSFS_DEBUG printf("vfs_hash_get(inode %lu) error %d\n", inode, error); #endif 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 | LK_NOWITNESS, 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); #ifdef MSDOSFS_DEBUG printf("vfs_hash_insert(inode %lu) error %d\n", inode, error); #endif 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; vn_set_state(nvp, VSTATE_CONSTRUCTED); 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) 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; struct vnode *vp = DETOV(dep); struct buf *bp; off_t eof_clusteroff; u_long count; int error; /* * The root of a DOS filesystem cannot be extended. */ if ((vp->v_vflag & VV_ROOT) != 0 && !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 != 0) goto rewind; } /* * For the case of cluster size larger than the page size, we * need to ensure that the possibly dirty partial buffer at * the old end of file is not filled with invalid pages by * extension. Otherwise it has a contradictory state of * B_CACHE | B_DELWRI but with invalid pages, and cannot be * neither written out nor validated. * * Fix it by proactively clearing extended pages. Need to do * both vfs_bio_clrbuf() to mark pages valid, and to zero * actual buffer content which might exist in the tail of the * already valid cluster. */ error = bread(vp, de_cluster(pmp, dep->de_FileSize), pmp->pm_bpcluster, NOCRED, &bp); if (error != 0) goto rewind; vfs_bio_clrbuf(bp); eof_clusteroff = de_cn2off(pmp, de_cluster(pmp, dep->de_FileSize)); vfs_bio_bzero_buf(bp, dep->de_FileSize - eof_clusteroff, pmp->pm_bpcluster - dep->de_FileSize + eof_clusteroff); if (!DOINGASYNC(vp)) (void)bwrite(bp); else if (vm_page_count_severe() || buf_dirty_count_severe()) bawrite(bp); else bdwrite(bp); vnode_pager_setsize(vp, length); dep->de_FileSize = length; dep->de_flag |= DE_UPDATE | DE_MODIFIED; return (deupdat(dep, !DOINGASYNC(vp))); rewind: /* truncate the added clusters away again */ (void)detrunc(dep, dep->de_FileSize, 0, cred); return (error); } /* * 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 = DETOI(dep->de_pmp, dep->de_dirclust, dep->de_diroffset); #ifdef MSDOSFS_DEBUG printf("vfs_hash_rehash(inode %lu, refcnt %lu, vp %p)\n", dep->de_inode, dep->de_refcnt, vp); #endif 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. */ #ifdef MSDOSFS_DEBUG printf("vfs_hash_remove(inode %lu, refcnt %lu, vp %p)\n", dep->de_inode, dep->de_refcnt, vp); #endif 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); }