The Design and Implementation of the FreeBSD Operating System, Second Edition
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sys/fs/msdosfs/msdosfs_denode.c

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    1 /* $FreeBSD$ */
    2 /*      $NetBSD: msdosfs_denode.c,v 1.28 1998/02/10 14:10:00 mrg Exp $  */
    3 
    4 /*-
    5  * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
    6  * Copyright (C) 1994, 1995, 1997 TooLs GmbH.
    7  * All rights reserved.
    8  * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below).
    9  *
   10  * Redistribution and use in source and binary forms, with or without
   11  * modification, are permitted provided that the following conditions
   12  * are met:
   13  * 1. Redistributions of source code must retain the above copyright
   14  *    notice, this list of conditions and the following disclaimer.
   15  * 2. Redistributions in binary form must reproduce the above copyright
   16  *    notice, this list of conditions and the following disclaimer in the
   17  *    documentation and/or other materials provided with the distribution.
   18  * 3. All advertising materials mentioning features or use of this software
   19  *    must display the following acknowledgement:
   20  *      This product includes software developed by TooLs GmbH.
   21  * 4. The name of TooLs GmbH may not be used to endorse or promote products
   22  *    derived from this software without specific prior written permission.
   23  *
   24  * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
   25  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   26  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
   27  * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   28  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
   29  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
   30  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
   31  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
   32  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
   33  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   34  */
   35 /*-
   36  * Written by Paul Popelka (paulp@uts.amdahl.com)
   37  *
   38  * You can do anything you want with this software, just don't say you wrote
   39  * it, and don't remove this notice.
   40  *
   41  * This software is provided "as is".
   42  *
   43  * The author supplies this software to be publicly redistributed on the
   44  * understanding that the author is not responsible for the correct
   45  * functioning of this software in any circumstances and is not liable for
   46  * any damages caused by this software.
   47  *
   48  * October 1992
   49  */
   50 
   51 #include <sys/param.h>
   52 #include <sys/systm.h>
   53 #include <sys/kernel.h>
   54 #include <sys/mount.h>
   55 #include <sys/malloc.h>
   56 #include <sys/bio.h>
   57 #include <sys/buf.h>
   58 #include <sys/vnode.h>
   59 #include <sys/mutex.h>
   60 
   61 #include <vm/vm.h>
   62 #include <vm/vm_extern.h>
   63 
   64 #include <fs/msdosfs/bpb.h>
   65 #include <fs/msdosfs/msdosfsmount.h>
   66 #include <fs/msdosfs/direntry.h>
   67 #include <fs/msdosfs/denode.h>
   68 #include <fs/msdosfs/fat.h>
   69 
   70 static MALLOC_DEFINE(M_MSDOSFSNODE, "MSDOSFS node", "MSDOSFS vnode private part");
   71 
   72 static struct denode **dehashtbl;
   73 static u_long dehash;                   /* size of hash table - 1 */
   74 #define DEHASH(dev, dcl, doff)  (dehashtbl[(minor(dev) + (dcl) + (doff) /       \
   75                                 sizeof(struct direntry)) & dehash])
   76 static struct mtx dehash_mtx;
   77 static int dehash_init;
   78 
   79 union _qcvt {
   80         quad_t qcvt;
   81         long val[2];
   82 };
   83 #define SETHIGH(q, h) { \
   84         union _qcvt tmp; \
   85         tmp.qcvt = (q); \
   86         tmp.val[_QUAD_HIGHWORD] = (h); \
   87         (q) = tmp.qcvt; \
   88 }
   89 #define SETLOW(q, l) { \
   90         union _qcvt tmp; \
   91         tmp.qcvt = (q); \
   92         tmp.val[_QUAD_LOWWORD] = (l); \
   93         (q) = tmp.qcvt; \
   94 }
   95 
   96 static struct denode *
   97                 msdosfs_hashget(struct cdev *dev, u_long dirclust, u_long diroff);
   98 static void     msdosfs_hashins(struct denode *dep);
   99 static void     msdosfs_hashrem(struct denode *dep);
  100 
  101 /*ARGSUSED*/
  102 int 
  103 msdosfs_init(vfsp)
  104         struct vfsconf *vfsp;
  105 {
  106         /*
  107          * The following lines prevent us from initializing the mutex
  108          * init multiple times.  I'm not sure why we get called multiple
  109          * times, but the following prevents the panic when we initalize
  110          * the mutext the second time.  XXX BAD XXX
  111          */
  112         if (dehash_init) {
  113                 printf("Warning: msdosfs_init called more than once!\n");
  114                 return (0);
  115         }
  116         dehash_init++;
  117         dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash);
  118         mtx_init(&dehash_mtx, "msdosfs dehash", NULL, MTX_DEF);
  119         return (0);
  120 }
  121 
  122 int 
  123 msdosfs_uninit(vfsp)
  124         struct vfsconf *vfsp;
  125 {
  126 
  127         if (dehashtbl)
  128                 free(dehashtbl, M_MSDOSFSMNT);
  129         mtx_destroy(&dehash_mtx);
  130         dehash_init--;
  131         return (0);
  132 }
  133 
  134 static struct denode *
  135 msdosfs_hashget(dev, dirclust, diroff)
  136         struct cdev *dev;
  137         u_long dirclust;
  138         u_long diroff;
  139 {
  140         struct thread *td = curthread;  /* XXX */
  141         struct denode *dep;
  142         struct vnode *vp;
  143 
  144 loop:
  145         mtx_lock(&dehash_mtx);
  146         for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) {
  147                 if (dirclust == dep->de_dirclust
  148                     && diroff == dep->de_diroffset
  149                     && dev == dep->de_dev
  150                     && dep->de_refcnt != 0) {
  151                         vp = DETOV(dep);
  152                         mtx_lock(&vp->v_interlock);
  153                         mtx_unlock(&dehash_mtx);
  154                         if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, td))
  155                                 goto loop;
  156                         return (dep);
  157                 }
  158         }
  159         mtx_unlock(&dehash_mtx);
  160         return (NULL);
  161 }
  162 
  163 static void
  164 msdosfs_hashins(dep)
  165         struct denode *dep;
  166 {
  167         struct denode **depp, *deq;
  168 
  169         mtx_lock(&dehash_mtx);
  170         depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset);
  171         deq = *depp;
  172         if (deq)
  173                 deq->de_prev = &dep->de_next;
  174         dep->de_next = deq;
  175         dep->de_prev = depp;
  176         *depp = dep;
  177         mtx_unlock(&dehash_mtx);
  178 }
  179 
  180 static void
  181 msdosfs_hashrem(dep)
  182         struct denode *dep;
  183 {
  184         struct denode *deq;
  185 
  186         mtx_lock(&dehash_mtx);
  187         deq = dep->de_next;
  188         if (deq)
  189                 deq->de_prev = dep->de_prev;
  190         *dep->de_prev = deq;
  191 #ifdef DIAGNOSTIC
  192         dep->de_next = NULL;
  193         dep->de_prev = NULL;
  194 #endif
  195         mtx_unlock(&dehash_mtx);
  196 }
  197 
  198 /*
  199  * If deget() succeeds it returns with the gotten denode locked().
  200  *
  201  * pmp       - address of msdosfsmount structure of the filesystem containing
  202  *             the denode of interest.  The pm_dev field and the address of
  203  *             the msdosfsmount structure are used.
  204  * dirclust  - which cluster bp contains, if dirclust is 0 (root directory)
  205  *             diroffset is relative to the beginning of the root directory,
  206  *             otherwise it is cluster relative.
  207  * diroffset - offset past begin of cluster of denode we want
  208  * depp      - returns the address of the gotten denode.
  209  */
  210 int
  211 deget(pmp, dirclust, diroffset, depp)
  212         struct msdosfsmount *pmp;       /* so we know the maj/min number */
  213         u_long dirclust;                /* cluster this dir entry came from */
  214         u_long diroffset;               /* index of entry within the cluster */
  215         struct denode **depp;           /* returns the addr of the gotten denode */
  216 {
  217         int error;
  218         struct cdev *dev = pmp->pm_dev;
  219         struct mount *mntp = pmp->pm_mountp;
  220         struct direntry *direntptr;
  221         struct denode *ldep;
  222         struct vnode *nvp;
  223         struct buf *bp;
  224         struct thread *td = curthread;  /* XXX */
  225         struct timeval tv;
  226 
  227 #ifdef MSDOSFS_DEBUG
  228         printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
  229             pmp, dirclust, diroffset, depp);
  230 #endif
  231 
  232         /*
  233          * On FAT32 filesystems, root is a (more or less) normal
  234          * directory
  235          */
  236         if (FAT32(pmp) && dirclust == MSDOSFSROOT)
  237                 dirclust = pmp->pm_rootdirblk;
  238 
  239         /*
  240          * See if the denode is in the denode cache. Use the location of
  241          * the directory entry to compute the hash value. For subdir use
  242          * address of "." entry. For root dir (if not FAT32) use cluster
  243          * MSDOSFSROOT, offset MSDOSFSROOT_OFS
  244          *
  245          * NOTE: The check for de_refcnt > 0 below insures the denode being
  246          * examined does not represent an unlinked but still open file.
  247          * These files are not to be accessible even when the directory
  248          * entry that represented the file happens to be reused while the
  249          * deleted file is still open.
  250          */
  251         ldep = msdosfs_hashget(dev, dirclust, diroffset);
  252         if (ldep) {
  253                 *depp = ldep;
  254                 return (0);
  255         }
  256 
  257         /*
  258          * Do the MALLOC before the getnewvnode since doing so afterward
  259          * might cause a bogus v_data pointer to get dereferenced
  260          * elsewhere if MALLOC should block.
  261          */
  262         MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK);
  263 
  264         /*
  265          * Directory entry was not in cache, have to create a vnode and
  266          * copy it from the passed disk buffer.
  267          */
  268         /* getnewvnode() does a VREF() on the vnode */
  269         error = getnewvnode("msdosfs", mntp, msdosfs_vnodeop_p, &nvp);
  270         if (error) {
  271                 *depp = NULL;
  272                 FREE(ldep, M_MSDOSFSNODE);
  273                 return error;
  274         }
  275         bzero((caddr_t)ldep, sizeof *ldep);
  276         nvp->v_data = ldep;
  277         ldep->de_vnode = nvp;
  278         ldep->de_flag = 0;
  279         ldep->de_devvp = 0;
  280         ldep->de_dev = dev;
  281         ldep->de_dirclust = dirclust;
  282         ldep->de_diroffset = diroffset;
  283         fc_purge(ldep, 0);      /* init the fat cache for this denode */
  284 
  285         /*
  286          * Lock the denode so that it can't be accessed until we've read
  287          * it in and have done what we need to it.  Do this here instead
  288          * of at the start of msdosfs_hashins() so that reinsert() can
  289          * call msdosfs_hashins() with a locked denode.
  290          */
  291         if (VOP_LOCK(nvp, LK_EXCLUSIVE, td) != 0)
  292                 panic("deget: unexpected lock failure");
  293 
  294         /*
  295          * Insert the denode into the hash queue.
  296          */
  297         msdosfs_hashins(ldep);
  298 
  299         ldep->de_pmp = pmp;
  300         ldep->de_refcnt = 1;
  301         /*
  302          * Copy the directory entry into the denode area of the vnode.
  303          */
  304         if ((dirclust == MSDOSFSROOT
  305              || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
  306             && diroffset == MSDOSFSROOT_OFS) {
  307                 /*
  308                  * Directory entry for the root directory. There isn't one,
  309                  * so we manufacture one. We should probably rummage
  310                  * through the root directory and find a label entry (if it
  311                  * exists), and then use the time and date from that entry
  312                  * as the time and date for the root denode.
  313                  */
  314                 nvp->v_vflag |= VV_ROOT; /* should be further down XXX */
  315 
  316                 ldep->de_Attributes = ATTR_DIRECTORY;
  317                 ldep->de_LowerCase = 0;
  318                 if (FAT32(pmp))
  319                         ldep->de_StartCluster = pmp->pm_rootdirblk;
  320                         /* de_FileSize will be filled in further down */
  321                 else {
  322                         ldep->de_StartCluster = MSDOSFSROOT;
  323                         ldep->de_FileSize = pmp->pm_rootdirsize * DEV_BSIZE;
  324                 }
  325                 /*
  326                  * fill in time and date so that dos2unixtime() doesn't
  327                  * spit up when called from msdosfs_getattr() with root
  328                  * denode
  329                  */
  330                 ldep->de_CHun = 0;
  331                 ldep->de_CTime = 0x0000;        /* 00:00:00      */
  332                 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
  333                     | (1 << DD_DAY_SHIFT);
  334                 /* Jan 1, 1980   */
  335                 ldep->de_ADate = ldep->de_CDate;
  336                 ldep->de_MTime = ldep->de_CTime;
  337                 ldep->de_MDate = ldep->de_CDate;
  338                 /* leave the other fields as garbage */
  339         } else {
  340                 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
  341                 if (error) {
  342                         /*
  343                          * The denode does not contain anything useful, so
  344                          * it would be wrong to leave it on its hash chain.
  345                          * Arrange for vput() to just forget about it.
  346                          */
  347                         ldep->de_Name[0] = SLOT_DELETED;
  348 
  349                         vput(nvp);
  350                         *depp = NULL;
  351                         return (error);
  352                 }
  353                 DE_INTERNALIZE(ldep, direntptr);
  354                 brelse(bp);
  355         }
  356 
  357         /*
  358          * Fill in a few fields of the vnode and finish filling in the
  359          * denode.  Then return the address of the found denode.
  360          */
  361         if (ldep->de_Attributes & ATTR_DIRECTORY) {
  362                 /*
  363                  * Since DOS directory entries that describe directories
  364                  * have 0 in the filesize field, we take this opportunity
  365                  * to find out the length of the directory and plug it into
  366                  * the denode structure.
  367                  */
  368                 u_long size;
  369 
  370                 /*
  371                  * XXX Sometimes, these arrives that . entry have cluster
  372                  * number 0, when it shouldn't.  Use real cluster number
  373                  * instead of what is written in directory entry.
  374                  */
  375                 if ((diroffset == 0) && (ldep->de_StartCluster != dirclust)) {
  376                         printf("deget(): . entry at clust %ld != %ld\n",
  377                                         dirclust, ldep->de_StartCluster);
  378                         ldep->de_StartCluster = dirclust;
  379                 }
  380 
  381                 nvp->v_type = VDIR;
  382                 if (ldep->de_StartCluster != MSDOSFSROOT) {
  383                         error = pcbmap(ldep, 0xffff, 0, &size, 0);
  384                         if (error == E2BIG) {
  385                                 ldep->de_FileSize = de_cn2off(pmp, size);
  386                                 error = 0;
  387                         } else
  388                                 printf("deget(): pcbmap returned %d\n", error);
  389                 }
  390         } else
  391                 nvp->v_type = VREG;
  392         getmicrouptime(&tv);
  393         SETHIGH(ldep->de_modrev, tv.tv_sec);
  394         SETLOW(ldep->de_modrev, tv.tv_usec * 4294);
  395         ldep->de_devvp = pmp->pm_devvp;
  396         VREF(ldep->de_devvp);
  397         *depp = ldep;
  398         return (0);
  399 }
  400 
  401 int
  402 deupdat(dep, waitfor)
  403         struct denode *dep;
  404         int waitfor;
  405 {
  406         int error;
  407         struct buf *bp;
  408         struct direntry *dirp;
  409         struct timespec ts;
  410 
  411         if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY)
  412                 return (0);
  413         getnanotime(&ts);
  414         DETIMES(dep, &ts, &ts, &ts);
  415         if ((dep->de_flag & DE_MODIFIED) == 0)
  416                 return (0);
  417         dep->de_flag &= ~DE_MODIFIED;
  418         if (dep->de_Attributes & ATTR_DIRECTORY)
  419                 return (0);
  420         if (dep->de_refcnt <= 0)
  421                 return (0);
  422         error = readde(dep, &bp, &dirp);
  423         if (error)
  424                 return (error);
  425         DE_EXTERNALIZE(dirp, dep);
  426         if (waitfor)
  427                 return (bwrite(bp));
  428         else {
  429                 bdwrite(bp);
  430                 return (0);
  431         }
  432 }
  433 
  434 /*
  435  * Truncate the file described by dep to the length specified by length.
  436  */
  437 int
  438 detrunc(dep, length, flags, cred, td)
  439         struct denode *dep;
  440         u_long length;
  441         int flags;
  442         struct ucred *cred;
  443         struct thread *td;
  444 {
  445         int error;
  446         int allerror;
  447         u_long eofentry;
  448         u_long chaintofree;
  449         daddr_t bn;
  450         int boff;
  451         int isadir = dep->de_Attributes & ATTR_DIRECTORY;
  452         struct buf *bp;
  453         struct msdosfsmount *pmp = dep->de_pmp;
  454 
  455 #ifdef MSDOSFS_DEBUG
  456         printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
  457 #endif
  458 
  459         /*
  460          * Disallow attempts to truncate the root directory since it is of
  461          * fixed size.  That's just the way dos filesystems are.  We use
  462          * the VROOT bit in the vnode because checking for the directory
  463          * bit and a startcluster of 0 in the denode is not adequate to
  464          * recognize the root directory at this point in a file or
  465          * directory's life.
  466          */
  467         if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp)) {
  468                 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
  469                     dep->de_dirclust, dep->de_diroffset);
  470                 return (EINVAL);
  471         }
  472 
  473 
  474         if (dep->de_FileSize < length) {
  475                 vnode_pager_setsize(DETOV(dep), length);
  476                 return deextend(dep, length, cred);
  477         }
  478 
  479         /*
  480          * If the desired length is 0 then remember the starting cluster of
  481          * the file and set the StartCluster field in the directory entry
  482          * to 0.  If the desired length is not zero, then get the number of
  483          * the last cluster in the shortened file.  Then get the number of
  484          * the first cluster in the part of the file that is to be freed.
  485          * Then set the next cluster pointer in the last cluster of the
  486          * file to CLUST_EOFE.
  487          */
  488         if (length == 0) {
  489                 chaintofree = dep->de_StartCluster;
  490                 dep->de_StartCluster = 0;
  491                 eofentry = ~0;
  492         } else {
  493                 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0, 
  494                                &eofentry, 0);
  495                 if (error) {
  496 #ifdef MSDOSFS_DEBUG
  497                         printf("detrunc(): pcbmap fails %d\n", error);
  498 #endif
  499                         return (error);
  500                 }
  501         }
  502 
  503         fc_purge(dep, de_clcount(pmp, length));
  504 
  505         /*
  506          * If the new length is not a multiple of the cluster size then we
  507          * must zero the tail end of the new last cluster in case it
  508          * becomes part of the file again because of a seek.
  509          */
  510         if ((boff = length & pmp->pm_crbomask) != 0) {
  511                 if (isadir) {
  512                         bn = cntobn(pmp, eofentry);
  513                         error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
  514                             NOCRED, &bp);
  515                         if (error) {
  516                                 brelse(bp);
  517 #ifdef MSDOSFS_DEBUG
  518                                 printf("detrunc(): bread fails %d\n", error);
  519 #endif
  520                                 return (error);
  521                         }
  522                         bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
  523                         if (flags & IO_SYNC)
  524                                 bwrite(bp);
  525                         else
  526                                 bdwrite(bp);
  527                 }
  528         }
  529 
  530         /*
  531          * Write out the updated directory entry.  Even if the update fails
  532          * we free the trailing clusters.
  533          */
  534         dep->de_FileSize = length;
  535         if (!isadir)
  536                 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
  537         allerror = vtruncbuf(DETOV(dep), cred, td, length, pmp->pm_bpcluster);
  538 #ifdef MSDOSFS_DEBUG
  539         if (allerror)
  540                 printf("detrunc(): vtruncbuf error %d\n", allerror);
  541 #endif
  542         error = deupdat(dep, 1);
  543         if (error && (allerror == 0))
  544                 allerror = error;
  545 #ifdef MSDOSFS_DEBUG
  546         printf("detrunc(): allerror %d, eofentry %lu\n",
  547                allerror, eofentry);
  548 #endif
  549 
  550         /*
  551          * If we need to break the cluster chain for the file then do it
  552          * now.
  553          */
  554         if (eofentry != ~0) {
  555                 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
  556                                  &chaintofree, CLUST_EOFE);
  557                 if (error) {
  558 #ifdef MSDOSFS_DEBUG
  559                         printf("detrunc(): fatentry errors %d\n", error);
  560 #endif
  561                         return (error);
  562                 }
  563                 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
  564                             eofentry);
  565         }
  566 
  567         /*
  568          * Now free the clusters removed from the file because of the
  569          * truncation.
  570          */
  571         if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
  572                 freeclusterchain(pmp, chaintofree);
  573 
  574         return (allerror);
  575 }
  576 
  577 /*
  578  * Extend the file described by dep to length specified by length.
  579  */
  580 int
  581 deextend(dep, length, cred)
  582         struct denode *dep;
  583         u_long length;
  584         struct ucred *cred;
  585 {
  586         struct msdosfsmount *pmp = dep->de_pmp;
  587         u_long count;
  588         int error;
  589 
  590         /*
  591          * The root of a DOS filesystem cannot be extended.
  592          */
  593         if ((DETOV(dep)->v_vflag & VV_ROOT) && !FAT32(pmp))
  594                 return (EINVAL);
  595 
  596         /*
  597          * Directories cannot be extended.
  598          */
  599         if (dep->de_Attributes & ATTR_DIRECTORY)
  600                 return (EISDIR);
  601 
  602         if (length <= dep->de_FileSize)
  603                 panic("deextend: file too large");
  604 
  605         /*
  606          * Compute the number of clusters to allocate.
  607          */
  608         count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
  609         if (count > 0) {
  610                 if (count > pmp->pm_freeclustercount)
  611                         return (ENOSPC);
  612                 error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
  613                 if (error) {
  614                         /* truncate the added clusters away again */
  615                         (void) detrunc(dep, dep->de_FileSize, 0, cred, NULL);
  616                         return (error);
  617                 }
  618         }
  619         dep->de_FileSize = length;
  620         dep->de_flag |= DE_UPDATE|DE_MODIFIED;
  621         return (deupdat(dep, 1));
  622 }
  623 
  624 /*
  625  * Move a denode to its correct hash queue after the file it represents has
  626  * been moved to a new directory.
  627  */
  628 void
  629 reinsert(dep)
  630         struct denode *dep;
  631 {
  632         /*
  633          * Fix up the denode cache.  If the denode is for a directory,
  634          * there is nothing to do since the hash is based on the starting
  635          * cluster of the directory file and that hasn't changed.  If for a
  636          * file the hash is based on the location of the directory entry,
  637          * so we must remove it from the cache and re-enter it with the
  638          * hash based on the new location of the directory entry.
  639          */
  640         if (dep->de_Attributes & ATTR_DIRECTORY)
  641                 return;
  642         msdosfs_hashrem(dep);
  643         msdosfs_hashins(dep);
  644 }
  645 
  646 int
  647 msdosfs_reclaim(ap)
  648         struct vop_reclaim_args /* {
  649                 struct vnode *a_vp;
  650         } */ *ap;
  651 {
  652         struct vnode *vp = ap->a_vp;
  653         struct denode *dep = VTODE(vp);
  654 
  655 #ifdef MSDOSFS_DEBUG
  656         printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
  657             dep, dep->de_Name, dep->de_refcnt);
  658 #endif
  659 
  660         if (prtactive && vrefcnt(vp) != 0)
  661                 vprint("msdosfs_reclaim(): pushing active", vp);
  662         /*
  663          * Remove the denode from its hash chain.
  664          */
  665         msdosfs_hashrem(dep);
  666         /*
  667          * Purge old data structures associated with the denode.
  668          */
  669         if (dep->de_devvp) {
  670                 vrele(dep->de_devvp);
  671                 dep->de_devvp = 0;
  672         }
  673 #if 0 /* XXX */
  674         dep->de_flag = 0;
  675 #endif
  676         FREE(dep, M_MSDOSFSNODE);
  677         vp->v_data = NULL;
  678 
  679         return (0);
  680 }
  681 
  682 int
  683 msdosfs_inactive(ap)
  684         struct vop_inactive_args /* {
  685                 struct vnode *a_vp;
  686                 struct thread *a_td;
  687         } */ *ap;
  688 {
  689         struct vnode *vp = ap->a_vp;
  690         struct denode *dep = VTODE(vp);
  691         struct thread *td = ap->a_td;
  692         int error = 0;
  693 
  694 #ifdef MSDOSFS_DEBUG
  695         printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
  696 #endif
  697 
  698         if (prtactive && vrefcnt(vp) != 0)
  699                 vprint("msdosfs_inactive(): pushing active", vp);
  700 
  701         /*
  702          * Ignore denodes related to stale file handles.
  703          */
  704         if (dep->de_Name[0] == SLOT_DELETED)
  705                 goto out;
  706 
  707         /*
  708          * If the file has been deleted and it is on a read/write
  709          * filesystem, then truncate the file, and mark the directory slot
  710          * as empty.  (This may not be necessary for the dos filesystem.)
  711          */
  712 #ifdef MSDOSFS_DEBUG
  713         printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n",
  714                dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY);
  715 #endif
  716         if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
  717                 error = detrunc(dep, (u_long) 0, 0, NOCRED, td);
  718                 dep->de_flag |= DE_UPDATE;
  719                 dep->de_Name[0] = SLOT_DELETED;
  720         }
  721         deupdat(dep, 0);
  722 
  723 out:
  724         VOP_UNLOCK(vp, 0, td);
  725         /*
  726          * If we are done with the denode, reclaim it
  727          * so that it can be reused immediately.
  728          */
  729 #ifdef MSDOSFS_DEBUG
  730         printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n",
  731                vrefcnt(vp), dep->de_Name[0]);
  732 #endif
  733         if (dep->de_Name[0] == SLOT_DELETED)
  734                 vrecycle(vp, NULL, td);
  735         return (error);
  736 }

Cache object: 1e725fd5bc83c1366528c727d605bf4a


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