The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/msdosfs/msdosfs_denode.c

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    1 /* $FreeBSD: src/sys/msdosfs/msdosfs_denode.c,v 1.18.2.2 1999/09/05 08:17:18 peter Exp $ */
    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/mount.h>
   54 #include <sys/malloc.h>
   55 #include <sys/proc.h>
   56 #include <sys/buf.h>
   57 #include <sys/vnode.h>
   58 #include <sys/kernel.h>         /* defines "time" */
   59 
   60 #include <vm/vm.h>
   61 #include <vm/vm_extern.h>
   62 
   63 #include <msdosfs/bpb.h>
   64 #include <msdosfs/msdosfsmount.h>
   65 #include <msdosfs/direntry.h>
   66 #include <msdosfs/denode.h>
   67 #include <msdosfs/fat.h>
   68 
   69 #ifdef __FreeBSD_version
   70 static MALLOC_DEFINE(M_MSDOSFSNODE, "MSDOSFS node", "MSDOSFS vnode private part");
   71 #else
   72 struct simplelock {int xxx;};
   73 #define simple_lock_init(x)
   74 #define simple_lock(x)
   75 #define simple_unlock(x)
   76 #endif
   77 
   78 static struct denode **dehashtbl;
   79 static u_long dehash;                   /* size of hash table - 1 */
   80 #define DEHASH(dev, dcl, doff)  (dehashtbl[((dev) + (dcl) + (doff) /    \
   81                                 sizeof(struct direntry)) & dehash])
   82 static struct simplelock dehash_slock;
   83 
   84 union _qcvt {
   85         quad_t qcvt;
   86         long val[2];
   87 };
   88 #define SETHIGH(q, h) { \
   89         union _qcvt tmp; \
   90         tmp.qcvt = (q); \
   91         tmp.val[_QUAD_HIGHWORD] = (h); \
   92         (q) = tmp.qcvt; \
   93 }
   94 #define SETLOW(q, l) { \
   95         union _qcvt tmp; \
   96         tmp.qcvt = (q); \
   97         tmp.val[_QUAD_LOWWORD] = (l); \
   98         (q) = tmp.qcvt; \
   99 }
  100 
  101 static struct denode *
  102                 msdosfs_hashget __P((dev_t dev, u_long dirclust,
  103                                      u_long diroff));
  104 static void     msdosfs_hashins __P((struct denode *dep));
  105 static void     msdosfs_hashrem __P((struct denode *dep));
  106 
  107 #ifdef __FreeBSD_version
  108 /*ARGSUSED*/
  109 int 
  110 msdosfs_init(vfsp)
  111         struct vfsconf *vfsp;
  112 {
  113         dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash);
  114         simple_lock_init(&dehash_slock);
  115         return (0);
  116 }
  117 #else
  118 int 
  119 msdosfs_init()
  120 {
  121         dehashtbl = hashinit(desiredvnodes/2, M_MSDOSFSMNT, &dehash);
  122         simple_lock_init(&dehash_slock);
  123         return (0);
  124 }
  125 #endif
  126 
  127 static struct denode *
  128 msdosfs_hashget(dev, dirclust, diroff)
  129         dev_t dev;
  130         u_long dirclust;
  131         u_long diroff;
  132 {
  133         struct proc *p = curproc;       /* XXX */
  134         struct denode *dep;
  135         struct vnode *vp;
  136 
  137 loop:
  138         simple_lock(&dehash_slock);
  139         for (dep = DEHASH(dev, dirclust, diroff); dep; dep = dep->de_next) {
  140                 if (dirclust == dep->de_dirclust
  141                     && diroff == dep->de_diroffset
  142                     && dev == dep->de_dev
  143                     && dep->de_refcnt != 0) {
  144                         vp = DETOV(dep);
  145                         simple_lock(&vp->v_interlock);
  146                         simple_unlock(&dehash_slock);
  147 #ifdef __FreeBSD_version
  148                         if (vget(vp, LK_EXCLUSIVE | LK_INTERLOCK, p))
  149 #else
  150                         if (dep->de_flag & DE_LOCKED) {
  151                                 dep->de_flag |= DE_WANTED;
  152                                 (void) tsleep((caddr_t)dep, PINOD, "msdhgt", 0);
  153                                 goto loop;
  154                         }
  155                         if (vget(vp, 1))
  156 #endif
  157                                 goto loop;
  158                         return (dep);
  159                 }
  160         }
  161         simple_unlock(&dehash_slock);
  162         return (NULL);
  163 }
  164 
  165 static void
  166 msdosfs_hashins(dep)
  167         struct denode *dep;
  168 {
  169         struct denode **depp, *deq;
  170 
  171         simple_lock(&dehash_slock);
  172         depp = &DEHASH(dep->de_dev, dep->de_dirclust, dep->de_diroffset);
  173         deq = *depp;
  174         if (deq)
  175                 deq->de_prev = &dep->de_next;
  176         dep->de_next = deq;
  177         dep->de_prev = depp;
  178         *depp = dep;
  179         simple_unlock(&dehash_slock);
  180 }
  181 
  182 static void
  183 msdosfs_hashrem(dep)
  184         struct denode *dep;
  185 {
  186         struct denode *deq;
  187 
  188         simple_lock(&dehash_slock);
  189         deq = dep->de_next;
  190         if (deq)
  191                 deq->de_prev = dep->de_prev;
  192         *dep->de_prev = deq;
  193 #ifdef DIAGNOSTIC
  194         dep->de_next = NULL;
  195         dep->de_prev = NULL;
  196 #endif
  197         simple_unlock(&dehash_slock);
  198 }
  199 
  200 /*
  201  * If deget() succeeds it returns with the gotten denode locked().
  202  *
  203  * pmp       - address of msdosfsmount structure of the filesystem containing
  204  *             the denode of interest.  The pm_dev field and the address of
  205  *             the msdosfsmount structure are used.
  206  * dirclust  - which cluster bp contains, if dirclust is 0 (root directory)
  207  *             diroffset is relative to the beginning of the root directory,
  208  *             otherwise it is cluster relative.
  209  * diroffset - offset past begin of cluster of denode we want
  210  * depp      - returns the address of the gotten denode.
  211  */
  212 int
  213 deget(pmp, dirclust, diroffset, depp)
  214         struct msdosfsmount *pmp;       /* so we know the maj/min number */
  215         u_long dirclust;                /* cluster this dir entry came from */
  216         u_long diroffset;               /* index of entry within the cluster */
  217         struct denode **depp;           /* returns the addr of the gotten denode */
  218 {
  219         int error;
  220         dev_t dev = pmp->pm_dev;
  221         struct mount *mntp = pmp->pm_mountp;
  222         struct direntry *direntptr;
  223         struct denode *ldep;
  224         struct vnode *nvp;
  225         struct buf *bp;
  226         struct proc *p = curproc;       /* XXX */
  227         struct timeval tv;
  228 
  229 #ifdef MSDOSFS_DEBUG
  230         printf("deget(pmp %p, dirclust %lu, diroffset %lx, depp %p)\n",
  231             pmp, dirclust, diroffset, depp);
  232 #endif
  233 
  234         /*
  235          * On FAT32 filesystems, root is a (more or less) normal
  236          * directory
  237          */
  238         if (FAT32(pmp) && dirclust == MSDOSFSROOT)
  239                 dirclust = pmp->pm_rootdirblk;
  240 
  241         /*
  242          * See if the denode is in the denode cache. Use the location of
  243          * the directory entry to compute the hash value. For subdir use
  244          * address of "." entry. For root dir (if not FAT32) use cluster
  245          * MSDOSFSROOT, offset MSDOSFSROOT_OFS
  246          *
  247          * NOTE: The check for de_refcnt > 0 below insures the denode being
  248          * examined does not represent an unlinked but still open file.
  249          * These files are not to be accessible even when the directory
  250          * entry that represented the file happens to be reused while the
  251          * deleted file is still open.
  252          */
  253         ldep = msdosfs_hashget(dev, dirclust, diroffset);
  254         if (ldep) {
  255                 *depp = ldep;
  256                 return (0);
  257         }
  258 
  259         /*
  260          * Do the MALLOC before the getnewvnode since doing so afterward
  261          * might cause a bogus v_data pointer to get dereferenced
  262          * elsewhere if MALLOC should block.
  263          */
  264         MALLOC(ldep, struct denode *, sizeof(struct denode), M_MSDOSFSNODE, M_WAITOK);
  265 
  266         /*
  267          * Directory entry was not in cache, have to create a vnode and
  268          * copy it from the passed disk buffer.
  269          */
  270         /* getnewvnode() does a VREF() on the vnode */
  271         error = getnewvnode(VT_MSDOSFS, mntp, msdosfs_vnodeop_p, &nvp);
  272         if (error) {
  273                 *depp = NULL;
  274                 FREE(ldep, M_MSDOSFSNODE);
  275                 return error;
  276         }
  277         bzero((caddr_t)ldep, sizeof *ldep);
  278 #ifdef __FreeBSD_version
  279         lockinit(&ldep->de_lock, PINOD, "denode", 0, 0);
  280 #endif
  281         nvp->v_data = ldep;
  282         ldep->de_vnode = nvp;
  283         ldep->de_flag = 0;
  284         ldep->de_devvp = 0;
  285         ldep->de_dev = dev;
  286         ldep->de_dirclust = dirclust;
  287         ldep->de_diroffset = diroffset;
  288         fc_purge(ldep, 0);      /* init the fat cache for this denode */
  289 
  290 #ifdef __FreeBSD_version
  291         /*
  292          * Lock the denode so that it can't be accessed until we've read
  293          * it in and have done what we need to it.  Do this here instead
  294          * of at the start of msdosfs_hashins() so that reinsert() can
  295          * call msdosfs_hashins() with a locked denode.
  296          */
  297         if (lockmgr(&ldep->de_lock, LK_EXCLUSIVE, (struct simplelock *)0, p))
  298                 panic("deget: unexpected lock failure");
  299 #endif
  300 
  301         /*
  302          * Insert the denode into the hash queue.
  303          */
  304 #ifndef __FreeBSD_version
  305         VOP_LOCK(nvp);
  306 #endif
  307         msdosfs_hashins(ldep);
  308 
  309         ldep->de_pmp = pmp;
  310         ldep->de_refcnt = 1;
  311         /*
  312          * Copy the directory entry into the denode area of the vnode.
  313          */
  314         if ((dirclust == MSDOSFSROOT
  315              || (FAT32(pmp) && dirclust == pmp->pm_rootdirblk))
  316             && diroffset == MSDOSFSROOT_OFS) {
  317                 /*
  318                  * Directory entry for the root directory. There isn't one,
  319                  * so we manufacture one. We should probably rummage
  320                  * through the root directory and find a label entry (if it
  321                  * exists), and then use the time and date from that entry
  322                  * as the time and date for the root denode.
  323                  */
  324                 nvp->v_flag |= VROOT; /* should be further down         XXX */
  325 
  326                 ldep->de_Attributes = ATTR_DIRECTORY;
  327                 if (FAT32(pmp))
  328                         ldep->de_StartCluster = pmp->pm_rootdirblk;
  329                         /* de_FileSize will be filled in further down */
  330                 else {
  331                         ldep->de_StartCluster = MSDOSFSROOT;
  332                         ldep->de_FileSize = pmp->pm_rootdirsize * pmp->pm_BytesPerSec;
  333                 }
  334                 /*
  335                  * fill in time and date so that dos2unixtime() doesn't
  336                  * spit up when called from msdosfs_getattr() with root
  337                  * denode
  338                  */
  339                 ldep->de_CHun = 0;
  340                 ldep->de_CTime = 0x0000;        /* 00:00:00      */
  341                 ldep->de_CDate = (0 << DD_YEAR_SHIFT) | (1 << DD_MONTH_SHIFT)
  342                     | (1 << DD_DAY_SHIFT);
  343                 /* Jan 1, 1980   */
  344                 ldep->de_ADate = ldep->de_CDate;
  345                 ldep->de_MTime = ldep->de_CTime;
  346                 ldep->de_MDate = ldep->de_CDate;
  347                 /* leave the other fields as garbage */
  348         } else {
  349                 error = readep(pmp, dirclust, diroffset, &bp, &direntptr);
  350                 if (error) {
  351                         /*
  352                          * The denode does not contain anything useful, so
  353                          * it would be wrong to leave it on its hash chain.
  354                          * Arrange for vput() to just forget about it.
  355                          */
  356                         ldep->de_Name[0] = SLOT_DELETED;
  357 
  358                         vput(nvp);
  359                         *depp = NULL;
  360                         return (error);
  361                 }
  362                 DE_INTERNALIZE(ldep, direntptr);
  363                 brelse(bp);
  364         }
  365 
  366         /*
  367          * Fill in a few fields of the vnode and finish filling in the
  368          * denode.  Then return the address of the found denode.
  369          */
  370         if (ldep->de_Attributes & ATTR_DIRECTORY) {
  371                 /*
  372                  * Since DOS directory entries that describe directories
  373                  * have 0 in the filesize field, we take this opportunity
  374                  * to find out the length of the directory and plug it into
  375                  * the denode structure.
  376                  */
  377                 u_long size;
  378 
  379                 nvp->v_type = VDIR;
  380                 if (ldep->de_StartCluster != MSDOSFSROOT) {
  381                         error = pcbmap(ldep, 0xffff, 0, &size, 0);
  382                         if (error == E2BIG) {
  383                                 ldep->de_FileSize = de_cn2off(pmp, size);
  384                                 error = 0;
  385                         } else
  386                                 printf("deget(): pcbmap returned %d\n", error);
  387                 }
  388         } else
  389                 nvp->v_type = VREG;
  390 #ifdef __FreeBSD_version
  391         getmicrouptime(&tv);
  392         SETHIGH(ldep->de_modrev, tv.tv_sec);
  393         SETLOW(ldep->de_modrev, tv.tv_usec * 4294);
  394 #else
  395         SETHIGH(ldep->de_modrev, mono_time.tv_sec);
  396         SETLOW(ldep->de_modrev, mono_time.tv_usec * 4294);
  397 #endif
  398         ldep->de_devvp = pmp->pm_devvp;
  399         VREF(ldep->de_devvp);
  400         *depp = ldep;
  401         return (0);
  402 }
  403 
  404 int
  405 deupdat(dep, waitfor)
  406         struct denode *dep;
  407         int waitfor;
  408 {
  409         int error;
  410         struct buf *bp;
  411         struct direntry *dirp;
  412         struct timespec ts;
  413 
  414         if (DETOV(dep)->v_mount->mnt_flag & MNT_RDONLY)
  415                 return (0);
  416 #ifdef __FreeBSD_version
  417         getnanotime(&ts);
  418 #else
  419         TIMEVAL_TO_TIMESPEC(&time, &ts);
  420 #endif
  421         DETIMES(dep, &ts, &ts, &ts);
  422         if ((dep->de_flag & DE_MODIFIED) == 0)
  423                 return (0);
  424         dep->de_flag &= ~DE_MODIFIED;
  425         if (dep->de_Attributes & ATTR_DIRECTORY)
  426                 return (0);
  427         if (dep->de_refcnt <= 0)
  428                 return (0);
  429         error = readde(dep, &bp, &dirp);
  430         if (error)
  431                 return (error);
  432         DE_EXTERNALIZE(dirp, dep);
  433         if (waitfor)
  434                 return (bwrite(bp));
  435         else {
  436                 bdwrite(bp);
  437                 return (0);
  438         }
  439 }
  440 
  441 /*
  442  * Truncate the file described by dep to the length specified by length.
  443  */
  444 int
  445 detrunc(dep, length, flags, cred, p)
  446         struct denode *dep;
  447         u_long length;
  448         int flags;
  449         struct ucred *cred;
  450         struct proc *p;
  451 {
  452         int error;
  453         int allerror;
  454         int vflags;
  455         u_long eofentry;
  456         u_long chaintofree;
  457         daddr_t bn;
  458         int boff;
  459         int isadir = dep->de_Attributes & ATTR_DIRECTORY;
  460         struct buf *bp;
  461         struct msdosfsmount *pmp = dep->de_pmp;
  462         struct timespec ts;
  463 
  464 #ifdef MSDOSFS_DEBUG
  465         printf("detrunc(): file %s, length %lu, flags %x\n", dep->de_Name, length, flags);
  466 #endif
  467 
  468         /*
  469          * Disallow attempts to truncate the root directory since it is of
  470          * fixed size.  That's just the way dos filesystems are.  We use
  471          * the VROOT bit in the vnode because checking for the directory
  472          * bit and a startcluster of 0 in the denode is not adequate to
  473          * recognize the root directory at this point in a file or
  474          * directory's life.
  475          */
  476         if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp)) {
  477                 printf("detrunc(): can't truncate root directory, clust %ld, offset %ld\n",
  478                     dep->de_dirclust, dep->de_diroffset);
  479                 return (EINVAL);
  480         }
  481 
  482 
  483         if (dep->de_FileSize < length) {
  484                 vnode_pager_setsize(DETOV(dep), length);
  485                 return deextend(dep, length, cred);
  486         }
  487 
  488         /*
  489          * If the desired length is 0 then remember the starting cluster of
  490          * the file and set the StartCluster field in the directory entry
  491          * to 0.  If the desired length is not zero, then get the number of
  492          * the last cluster in the shortened file.  Then get the number of
  493          * the first cluster in the part of the file that is to be freed.
  494          * Then set the next cluster pointer in the last cluster of the
  495          * file to CLUST_EOFE.
  496          */
  497         if (length == 0) {
  498                 chaintofree = dep->de_StartCluster;
  499                 dep->de_StartCluster = 0;
  500                 eofentry = ~0;
  501         } else {
  502                 error = pcbmap(dep, de_clcount(pmp, length) - 1, 0, 
  503                                &eofentry, 0);
  504                 if (error) {
  505 #ifdef MSDOSFS_DEBUG
  506                         printf("detrunc(): pcbmap fails %d\n", error);
  507 #endif
  508                         return (error);
  509                 }
  510         }
  511 
  512         fc_purge(dep, de_clcount(pmp, length));
  513 
  514         /*
  515          * If the new length is not a multiple of the cluster size then we
  516          * must zero the tail end of the new last cluster in case it
  517          * becomes part of the file again because of a seek.
  518          */
  519         if ((boff = length & pmp->pm_crbomask) != 0) {
  520                 if (isadir) {
  521                         bn = cntobn(pmp, eofentry);
  522                         error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster,
  523                             NOCRED, &bp);
  524                 } else {
  525                         bn = de_blk(pmp, length);
  526 #ifdef  PC98
  527                         /*
  528                          * 1024 byte/sector support
  529                          */
  530                         if (pmp->pm_BytesPerSec == 1024)
  531                                 DETOV(dep)->v_flag |= 0x10000;
  532 #endif
  533                         error = bread(DETOV(dep), bn, pmp->pm_bpcluster,
  534                             NOCRED, &bp);
  535                 }
  536                 if (error) {
  537                         brelse(bp);
  538 #ifdef MSDOSFS_DEBUG
  539                         printf("detrunc(): bread fails %d\n", error);
  540 #endif
  541                         return (error);
  542                 }
  543                 /*
  544                  * is this the right place for it?
  545                  */
  546                 bzero(bp->b_data + boff, pmp->pm_bpcluster - boff);
  547                 if (flags & IO_SYNC)
  548                         bwrite(bp);
  549                 else
  550                         bdwrite(bp);
  551         }
  552 
  553         /*
  554          * Write out the updated directory entry.  Even if the update fails
  555          * we free the trailing clusters.
  556          */
  557         dep->de_FileSize = length;
  558         if (!isadir)
  559                 dep->de_flag |= DE_UPDATE|DE_MODIFIED;
  560         vflags = (length > 0 ? V_SAVE : 0) | V_SAVEMETA;
  561         vinvalbuf(DETOV(dep), vflags, cred, p, 0, 0);
  562         vnode_pager_setsize(DETOV(dep), length);
  563         allerror = deupdat(dep, 1);
  564 #ifdef MSDOSFS_DEBUG
  565         printf("detrunc(): allerror %d, eofentry %lu\n",
  566                allerror, eofentry);
  567 #endif
  568 
  569         /*
  570          * If we need to break the cluster chain for the file then do it
  571          * now.
  572          */
  573         if (eofentry != ~0) {
  574                 error = fatentry(FAT_GET_AND_SET, pmp, eofentry,
  575                                  &chaintofree, CLUST_EOFE);
  576                 if (error) {
  577 #ifdef MSDOSFS_DEBUG
  578                         printf("detrunc(): fatentry errors %d\n", error);
  579 #endif
  580                         return (error);
  581                 }
  582                 fc_setcache(dep, FC_LASTFC, de_cluster(pmp, length - 1),
  583                             eofentry);
  584         }
  585 
  586         /*
  587          * Now free the clusters removed from the file because of the
  588          * truncation.
  589          */
  590         if (chaintofree != 0 && !MSDOSFSEOF(pmp, chaintofree))
  591                 freeclusterchain(pmp, chaintofree);
  592 
  593         return (allerror);
  594 }
  595 
  596 /*
  597  * Extend the file described by dep to length specified by length.
  598  */
  599 int
  600 deextend(dep, length, cred)
  601         struct denode *dep;
  602         u_long length;
  603         struct ucred *cred;
  604 {
  605         struct msdosfsmount *pmp = dep->de_pmp;
  606         u_long count;
  607         int error;
  608         struct timespec ts;
  609 
  610         /*
  611          * The root of a DOS filesystem cannot be extended.
  612          */
  613         if ((DETOV(dep)->v_flag & VROOT) && !FAT32(pmp))
  614                 return (EINVAL);
  615 
  616         /*
  617          * Directories cannot be extended.
  618          */
  619         if (dep->de_Attributes & ATTR_DIRECTORY)
  620                 return (EISDIR);
  621 
  622         if (length <= dep->de_FileSize)
  623                 panic("deextend: file too large");
  624 
  625         /*
  626          * Compute the number of clusters to allocate.
  627          */
  628         count = de_clcount(pmp, length) - de_clcount(pmp, dep->de_FileSize);
  629         if (count > 0) {
  630                 if (count > pmp->pm_freeclustercount)
  631                         return (ENOSPC);
  632                 error = extendfile(dep, count, NULL, NULL, DE_CLEAR);
  633                 if (error) {
  634                         /* truncate the added clusters away again */
  635                         (void) detrunc(dep, dep->de_FileSize, 0, cred, NULL);
  636                         return (error);
  637                 }
  638         }
  639         dep->de_FileSize = length;
  640         dep->de_flag |= DE_UPDATE|DE_MODIFIED;
  641         return (deupdat(dep, 1));
  642 }
  643 
  644 /*
  645  * Move a denode to its correct hash queue after the file it represents has
  646  * been moved to a new directory.
  647  */
  648 void
  649 reinsert(dep)
  650         struct denode *dep;
  651 {
  652         /*
  653          * Fix up the denode cache.  If the denode is for a directory,
  654          * there is nothing to do since the hash is based on the starting
  655          * cluster of the directory file and that hasn't changed.  If for a
  656          * file the hash is based on the location of the directory entry,
  657          * so we must remove it from the cache and re-enter it with the
  658          * hash based on the new location of the directory entry.
  659          */
  660         if (dep->de_Attributes & ATTR_DIRECTORY)
  661                 return;
  662         msdosfs_hashrem(dep);
  663         msdosfs_hashins(dep);
  664 }
  665 
  666 int
  667 msdosfs_reclaim(ap)
  668         struct vop_reclaim_args /* {
  669                 struct vnode *a_vp;
  670         } */ *ap;
  671 {
  672         struct vnode *vp = ap->a_vp;
  673         struct denode *dep = VTODE(vp);
  674 
  675 #ifdef MSDOSFS_DEBUG
  676         printf("msdosfs_reclaim(): dep %p, file %s, refcnt %ld\n",
  677             dep, dep->de_Name, dep->de_refcnt);
  678 #endif
  679 
  680         if (prtactive && vp->v_usecount != 0)
  681                 vprint("msdosfs_reclaim(): pushing active", vp);
  682         /*
  683          * Remove the denode from its hash chain.
  684          */
  685         msdosfs_hashrem(dep);
  686         /*
  687          * Purge old data structures associated with the denode.
  688          */
  689         cache_purge(vp);
  690         if (dep->de_devvp) {
  691                 vrele(dep->de_devvp);
  692                 dep->de_devvp = 0;
  693         }
  694 #if 0 /* XXX */
  695         dep->de_flag = 0;
  696 #endif
  697         FREE(dep, M_MSDOSFSNODE);
  698         vp->v_data = NULL;
  699 
  700         return (0);
  701 }
  702 
  703 int
  704 msdosfs_inactive(ap)
  705         struct vop_inactive_args /* {
  706                 struct vnode *a_vp;
  707                 struct proc *a_p;
  708         } */ *ap;
  709 {
  710         struct vnode *vp = ap->a_vp;
  711         struct denode *dep = VTODE(vp);
  712 #ifdef __FreeBSD_version
  713         struct proc *p = ap->a_p;
  714 #endif
  715         int error = 0;
  716         struct timespec ts;
  717 
  718 #ifdef MSDOSFS_DEBUG
  719         printf("msdosfs_inactive(): dep %p, de_Name[0] %x\n", dep, dep->de_Name[0]);
  720 #endif
  721 
  722         if (prtactive && vp->v_usecount != 0)
  723                 vprint("msdosfs_inactive(): pushing active", vp);
  724 
  725         /*
  726          * Ignore denodes related to stale file handles.
  727          */
  728         if (dep->de_Name[0] == SLOT_DELETED)
  729                 goto out;
  730 
  731         /*
  732          * If the file has been deleted and it is on a read/write
  733          * filesystem, then truncate the file, and mark the directory slot
  734          * as empty.  (This may not be necessary for the dos filesystem.)
  735          */
  736 #ifdef MSDOSFS_DEBUG
  737         printf("msdosfs_inactive(): dep %p, refcnt %ld, mntflag %x, MNT_RDONLY %x\n",
  738                dep, dep->de_refcnt, vp->v_mount->mnt_flag, MNT_RDONLY);
  739 #endif
  740 #ifndef __FreeBSD_version
  741         VOP_LOCK(vp);
  742 #endif
  743         if (dep->de_refcnt <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
  744 #ifdef __FreeBSD_version
  745                 error = detrunc(dep, (u_long) 0, 0, NOCRED, p);
  746 #else
  747                 error = detrunc(dep, (u_long) 0, 0, NOCRED, NULL);
  748 #endif
  749                 dep->de_flag |= DE_UPDATE;
  750                 dep->de_Name[0] = SLOT_DELETED;
  751         }
  752         deupdat(dep, 0);
  753 
  754 out:
  755 #ifdef __FreeBSD_version
  756         VOP_UNLOCK(vp, 0, p);
  757 #else
  758         VOP_UNLOCK(vp);
  759 #endif
  760         /*
  761          * If we are done with the denode, reclaim it
  762          * so that it can be reused immediately.
  763          */
  764 #ifdef MSDOSFS_DEBUG
  765         printf("msdosfs_inactive(): v_usecount %d, de_Name[0] %x\n", vp->v_usecount,
  766                dep->de_Name[0]);
  767 #endif
  768         if (dep->de_Name[0] == SLOT_DELETED)
  769                 vrecycle(vp, (struct simplelock *)0, p);
  770         return (error);
  771 }

Cache object: a6298c56de7bee507c658152d8cf67d9


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