diff options
Diffstat (limited to 'sys/fs/msdosfs/msdosfs_denode.c')
-rw-r--r-- | sys/fs/msdosfs/msdosfs_denode.c | 712 |
1 files changed, 712 insertions, 0 deletions
diff --git a/sys/fs/msdosfs/msdosfs_denode.c b/sys/fs/msdosfs/msdosfs_denode.c new file mode 100644 index 0000000..d864ddb --- /dev/null +++ b/sys/fs/msdosfs/msdosfs_denode.c @@ -0,0 +1,712 @@ +/* $FreeBSD$ */ +/* $NetBSD: msdosfs_denode.c,v 1.28 1998/02/10 14:10:00 mrg Exp $ */ + +/*- + * 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 <sys/param.h> +#include <sys/systm.h> +#include <sys/kernel.h> +#include <sys/mount.h> +#include <sys/malloc.h> +#include <sys/proc.h> +#include <sys/buf.h> +#include <sys/vnode.h> + +#include <vm/vm.h> +#include <vm/vm_extern.h> + +#include <msdosfs/bpb.h> +#include <msdosfs/msdosfsmount.h> +#include <msdosfs/direntry.h> +#include <msdosfs/denode.h> +#include <msdosfs/fat.h> + +static MALLOC_DEFINE(M_MSDOSFSNODE, "MSDOSFS node", "MSDOSFS vnode private part"); + +static struct denode **dehashtbl; +static u_long dehash; /* size of hash table - 1 */ +#define DEHASH(dev, dcl, doff) (dehashtbl[(minor(dev) + (dcl) + (doff) / \ + sizeof(struct direntry)) & dehash]) +#ifndef NULL_SIMPLELOCKS +static struct simplelock dehash_slock; +#endif + +union _qcvt { + quad_t qcvt; + long val[2]; +}; +#define SETHIGH(q, h) { \ + union _qcvt tmp; \ + tmp.qcvt = (q); \ + tmp.val[_QUAD_HIGHWORD] = (h); \ + (q) = tmp.qcvt; \ +} +#define SETLOW(q, l) { \ + union _qcvt tmp; \ + tmp.qcvt = (q); \ + tmp.val[_QUAD_LOWWORD] = (l); \ + (q) = tmp.qcvt; \ +} + +static struct denode * + msdosfs_hashget __P((dev_t dev, u_long dirclust, + u_long diroff)); +static void msdosfs_hashins __P((struct denode *dep)); +static void msdosfs_hashrem __P((struct denode *dep)); + +/*ARGSUSED*/ +int +msdosfs_init(vfsp) + struct vfsconf *vfsp; +{ + dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash); + simple_lock_init(&dehash_slock); + return (0); +} + +static struct denode * +msdosfs_hashget(dev, dirclust, diroff) + dev_t dev; + u_long dirclust; + u_long diroff; +{ + struct proc *p = curproc; /* XXX */ + struct denode *dep; + struct vnode *vp; + +loop: + simple_lock(&dehash_slock); + for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) { + if (dirclust == dep->de_dirclust + && diroff == dep->de_diroffset + && dev == dep->de_dev + && dep->de_refcnt != 0) { + vp = DETOV(dep); + simple_lock(&vp->v_interlock); + simple_unlock(&dehash_slock); + if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, p)) + goto loop; + return (dep); + } + } + simple_unlock(&dehash_slock); + return (NULL); +} + +static void +msdosfs_hashins(dep) + struct denode *dep; +{ + struct denode **depp, *deq; + + simple_lock(&dehash_slock); + depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset); + deq = *depp; + if (deq) + deq->de_prev = &dep->de_next; + dep->de_next = deq; + dep->de_prev = depp; + *depp = dep; + simple_unlock(&dehash_slock); +} + +static void +msdosfs_hashrem(dep) + struct denode *dep; +{ + struct denode *deq; + + simple_lock(&dehash_slock); + deq = dep->de_next; + if (deq) + deq->de_prev = dep->de_prev; + *dep->de_prev = deq; +#ifdef DIAGNOSTIC + dep->de_next = NULL; + dep->de_prev = NULL; +#endif + simple_unlock(&dehash_slock); +} + +/* + * If deget() succeeds it returns with the gotten denode locked(). + * + * pmp - address of msdosfsmount structure of the filesystem containing + * the denode of interest. The pm_dev field and 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 + * depp - returns the address of the gotten denode. + */ +int +deget(pmp, dirclust, diroffset, depp) + struct msdosfsmount *pmp; /* so we know the maj/min number */ + u_long dirclust; /* cluster this dir entry came from */ + u_long diroffset; /* index of entry within the cluster */ + struct denode **depp; /* returns the addr of the gotten denode */ +{ + int error; + dev_t dev = pmp->pm_dev; + struct mount *mntp = pmp->pm_mountp; + struct direntry *direntptr; + struct denode *ldep; + struct vnode *nvp; + struct buf *bp; + struct proc *p = curproc; /* XXX */ + struct timeval tv; + +#ifdef MSDOSFS_DEBUG + printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n", + pmp, dirclust, diroffset, depp); +#endif + + /* + * 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: The check for de_refcnt > 0 below insures the denode being + * examined does not represent 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. + */ + ldep = msdosfs_hashget(dev, dirclust, diroffset); + if (ldep) { + *depp = ldep; + return (0); + } + + /* + * Do the MALLOC before the getnewvnode since doing so afterward + * might cause a bogus v_data pointer to get dereferenced + * elsewhere if MALLOC should block. + */ + MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK); + + /* + * 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(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp); + if (error) { + *depp = NULL; + FREE(ldep, M_MSDOSFSNODE); + return error; + } + bzero((caddr_t)ldep, sizeof *ldep); + lockinit(&ldep->de_lock, PINOD, "denode", 0, 0); + nvp->v_data = ldep; + ldep->de_vnode = nvp; + ldep->de_flag = 0; + ldep->de_devvp = 0; + ldep->de_dev = dev; + ldep->de_dirclust = dirclust; + ldep->de_diroffset = diroffset; + fc_purge(ldep, 0); /* init the fat cache for this denode */ + + /* + * Lock the denode so that it can't be accessed until we've read + * it in and have done what we need to it. Do this here instead + * of at the start of msdosfs_hashins() so that reinsert() can + * call msdosfs_hashins() with a locked denode. + */ + if (lockmgr(&ldep->de_lock, LK_EXCLUSIVE, (struct simplelock *)0, p)) + panic("deget: unexpected lock failure"); + + /* + * Insert the denode into the hash queue. + */ + msdosfs_hashins(ldep); + + 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_flag |= VROOT; /* 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 * pmp->pm_BytesPerSec; + } + /* + * fill in time and date so that dos2unixtime() 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; + + vput(nvp); + *depp = NULL; + return (error); + } + 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; + + 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 + printf("deget(): pcbmap returned %d\n", error); + } + } else + nvp->v_type = VREG; + getmicrouptime(&tv); + SETHIGH(ldep->de_modrev, tv.tv_sec); + SETLOW(ldep->de_modrev, tv.tv_usec * 4294); + ldep->de_devvp = pmp->pm_devvp; + VREF(ldep->de_devvp); + *depp = ldep; + return (0); +} + +int +deupdat(dep, waitfor) + struct denode *dep; + int waitfor; +{ + int error; + struct buf *bp; + struct direntry *dirp; + struct timespec ts; + + if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY) + return (0); + getnanotime(&ts); + DETIMES(dep, &ts, &ts, &ts); + if ((dep->de_flag & DE_MODIFIED) == 0) + return (0); + dep->de_flag &= ~DE_MODIFIED; + if (dep->de_Attributes & ATTR_DIRECTORY) + return (0); + if (dep->de_refcnt <= 0) + return (0); + error = readde(dep, &bp, &dirp); + if (error) + return (error); + DE_EXTERNALIZE(dirp, dep); + if (waitfor) + return (bwrite(bp)); + else { + bdwrite(bp); + return (0); + } +} + +/* + * Truncate the file described by dep to the length specified by length. + */ +int +detrunc(dep, length, flags, cred, p) + struct denode *dep; + u_long length; + int flags; + struct ucred *cred; + struct proc *p; +{ + 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_flag & VROOT) && !FAT32(pmp)) { + printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n", + dep->de_dirclust, dep->de_diroffset); + 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 { + bn = de_blk(pmp, length); + error = bread(DETOV(dep), bn, pmp->pm_bpcluster, + NOCRED, &bp); + } + if (error) { + brelse(bp); +#ifdef MSDOSFS_DEBUG + printf("detrunc(): bread fails %d\n", error); +#endif + return (error); + } + /* + * is this the right place for it? + */ + bzero(bp->b_data + boff, pmp->pm_bpcluster - boff); + if (flags & IO_SYNC) + 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), cred, p, length, pmp->pm_bpcluster); +#ifdef MSDOSFS_DEBUG + if (allerror) + printf("detrunc(): vtruncbuf error %d\n", allerror); +#endif + error = deupdat(dep, 1); + if (error && (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(dep, length, cred) + 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_flag & VROOT) && !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, NULL); + return (error); + } + } + dep->de_FileSize = length; + dep->de_flag |= DE_UPDATE|DE_MODIFIED; + return (deupdat(dep, 1)); +} + +/* + * Move a denode to its correct hash queue after the file it represents has + * been moved to a new directory. + */ +void +reinsert(dep) + struct denode *dep; +{ + /* + * 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 (dep->de_Attributes & ATTR_DIRECTORY) + return; + msdosfs_hashrem(dep); + msdosfs_hashins(dep); +} + +int +msdosfs_reclaim(ap) + struct vop_reclaim_args /* { + struct vnode *a_vp; + } */ *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 + + if (prtactive && vp->v_usecount != 0) + vprint("msdosfs_reclaim(): pushing active", vp); + /* + * Remove the denode from its hash chain. + */ + msdosfs_hashrem(dep); + /* + * Purge old data structures associated with the denode. + */ + cache_purge(vp); + if (dep->de_devvp) { + vrele(dep->de_devvp); + dep->de_devvp = 0; + } +#if 0 /* XXX */ + dep->de_flag = 0; +#endif + FREE(dep, M_MSDOSFSNODE); + vp->v_data = NULL; + + return (0); +} + +int +msdosfs_inactive(ap) + struct vop_inactive_args /* { + struct vnode *a_vp; + struct proc *a_p; + } */ *ap; +{ + struct vnode *vp = ap->a_vp; + struct denode *dep = VTODE(vp); + struct proc *p = ap->a_p; + int error = 0; + +#ifdef MSDOSFS_DEBUG + printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]); +#endif + + if (prtactive && vp->v_usecount != 0) + vprint("msdosfs_inactive(): pushing active", vp); + + /* + * Ignore denodes related to stale file handles. + */ + if (dep->de_Name[0] == SLOT_DELETED) + 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 %x, MNT_RDONLY %x\n", + dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY); +#endif + if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { + error = detrunc(dep, (u_long) 0, 0, NOCRED, p); + dep->de_flag |= DE_UPDATE; + dep->de_Name[0] = SLOT_DELETED; + } + deupdat(dep, 0); + +out: + VOP_UNLOCK(vp, 0, p); + /* + * 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", vp->v_usecount, + dep->de_Name[0]); +#endif + if (dep->de_Name[0] == SLOT_DELETED) + vrecycle(vp, (struct simplelock *)0, p); + return (error); +} |