The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/fs/ext2fs/ext2_inode.c

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    1 /*-
    2  *  modified for Lites 1.1
    3  *
    4  *  Aug 1995, Godmar Back (gback@cs.utah.edu)
    5  *  University of Utah, Department of Computer Science
    6  */
    7 /*-
    8  * SPDX-License-Identifier: BSD-3-Clause
    9  *
   10  * Copyright (c) 1982, 1986, 1989, 1993
   11  *      The Regents of the University of California.  All rights reserved.
   12  *
   13  * Redistribution and use in source and binary forms, with or without
   14  * modification, are permitted provided that the following conditions
   15  * are met:
   16  * 1. Redistributions of source code must retain the above copyright
   17  *    notice, this list of conditions and the following disclaimer.
   18  * 2. Redistributions in binary form must reproduce the above copyright
   19  *    notice, this list of conditions and the following disclaimer in the
   20  *    documentation and/or other materials provided with the distribution.
   21  * 3. Neither the name of the University nor the names of its contributors
   22  *    may be used to endorse or promote products derived from this software
   23  *    without specific prior written permission.
   24  *
   25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   35  * SUCH DAMAGE.
   36  *
   37  *      @(#)ffs_inode.c 8.5 (Berkeley) 12/30/93
   38  * $FreeBSD: releng/12.0/sys/fs/ext2fs/ext2_inode.c 333584 2018-05-13 19:19:10Z fsu $
   39  */
   40 
   41 #include <sys/param.h>
   42 #include <sys/systm.h>
   43 #include <sys/mount.h>
   44 #include <sys/bio.h>
   45 #include <sys/buf.h>
   46 #include <sys/vnode.h>
   47 #include <sys/malloc.h>
   48 #include <sys/rwlock.h>
   49 
   50 #include <vm/vm.h>
   51 #include <vm/vm_extern.h>
   52 
   53 #include <fs/ext2fs/fs.h>
   54 #include <fs/ext2fs/inode.h>
   55 #include <fs/ext2fs/ext2_mount.h>
   56 #include <fs/ext2fs/ext2fs.h>
   57 #include <fs/ext2fs/fs.h>
   58 #include <fs/ext2fs/ext2_extern.h>
   59 #include <fs/ext2fs/ext2_extattr.h>
   60 
   61 /*
   62  * Update the access, modified, and inode change times as specified by the
   63  * IN_ACCESS, IN_UPDATE, and IN_CHANGE flags respectively.  Write the inode
   64  * to disk if the IN_MODIFIED flag is set (it may be set initially, or by
   65  * the timestamp update).  The IN_LAZYMOD flag is set to force a write
   66  * later if not now.  If we write now, then clear both IN_MODIFIED and
   67  * IN_LAZYMOD to reflect the presumably successful write, and if waitfor is
   68  * set, then wait for the write to complete.
   69  */
   70 int
   71 ext2_update(struct vnode *vp, int waitfor)
   72 {
   73         struct m_ext2fs *fs;
   74         struct buf *bp;
   75         struct inode *ip;
   76         int error;
   77 
   78         ASSERT_VOP_ELOCKED(vp, "ext2_update");
   79         ext2_itimes(vp);
   80         ip = VTOI(vp);
   81         if ((ip->i_flag & IN_MODIFIED) == 0 && waitfor == 0)
   82                 return (0);
   83         ip->i_flag &= ~(IN_LAZYACCESS | IN_LAZYMOD | IN_MODIFIED);
   84         fs = ip->i_e2fs;
   85         if (fs->e2fs_ronly)
   86                 return (0);
   87         if ((error = bread(ip->i_devvp,
   88             fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
   89             (int)fs->e2fs_bsize, NOCRED, &bp)) != 0) {
   90                 brelse(bp);
   91                 return (error);
   92         }
   93         error = ext2_i2ei(ip, (struct ext2fs_dinode *)((char *)bp->b_data +
   94             EXT2_INODE_SIZE(fs) * ino_to_fsbo(fs, ip->i_number)));
   95         if (error) {
   96                 brelse(bp);
   97                 return (error);
   98         }
   99         if (waitfor && !DOINGASYNC(vp))
  100                 return (bwrite(bp));
  101         else {
  102                 bdwrite(bp);
  103                 return (0);
  104         }
  105 }
  106 
  107 #define SINGLE  0       /* index of single indirect block */
  108 #define DOUBLE  1       /* index of double indirect block */
  109 #define TRIPLE  2       /* index of triple indirect block */
  110 
  111 /*
  112  * Release blocks associated with the inode ip and stored in the indirect
  113  * block bn.  Blocks are free'd in LIFO order up to (but not including)
  114  * lastbn.  If level is greater than SINGLE, the block is an indirect block
  115  * and recursive calls to indirtrunc must be used to cleanse other indirect
  116  * blocks.
  117  *
  118  * NB: triple indirect blocks are untested.
  119  */
  120 static int
  121 ext2_indirtrunc(struct inode *ip, daddr_t lbn, daddr_t dbn,
  122     daddr_t lastbn, int level, e4fs_daddr_t *countp)
  123 {
  124         struct buf *bp;
  125         struct m_ext2fs *fs = ip->i_e2fs;
  126         struct vnode *vp;
  127         e2fs_daddr_t *bap, *copy;
  128         int i, nblocks, error = 0, allerror = 0;
  129         e2fs_lbn_t nb, nlbn, last;
  130         e4fs_daddr_t blkcount, factor, blocksreleased = 0;
  131 
  132         /*
  133          * Calculate index in current block of last
  134          * block to be kept.  -1 indicates the entire
  135          * block so we need not calculate the index.
  136          */
  137         factor = 1;
  138         for (i = SINGLE; i < level; i++)
  139                 factor *= NINDIR(fs);
  140         last = lastbn;
  141         if (lastbn > 0)
  142                 last /= factor;
  143         nblocks = btodb(fs->e2fs_bsize);
  144         /*
  145          * Get buffer of block pointers, zero those entries corresponding
  146          * to blocks to be free'd, and update on disk copy first.  Since
  147          * double(triple) indirect before single(double) indirect, calls
  148          * to bmap on these blocks will fail.  However, we already have
  149          * the on disk address, so we have to set the b_blkno field
  150          * explicitly instead of letting bread do everything for us.
  151          */
  152         vp = ITOV(ip);
  153         bp = getblk(vp, lbn, (int)fs->e2fs_bsize, 0, 0, 0);
  154         if ((bp->b_flags & (B_DONE | B_DELWRI)) == 0) {
  155                 bp->b_iocmd = BIO_READ;
  156                 if (bp->b_bcount > bp->b_bufsize)
  157                         panic("ext2_indirtrunc: bad buffer size");
  158                 bp->b_blkno = dbn;
  159                 vfs_busy_pages(bp, 0);
  160                 bp->b_iooffset = dbtob(bp->b_blkno);
  161                 bstrategy(bp);
  162                 error = bufwait(bp);
  163         }
  164         if (error) {
  165                 brelse(bp);
  166                 *countp = 0;
  167                 return (error);
  168         }
  169         bap = (e2fs_daddr_t *)bp->b_data;
  170         copy = malloc(fs->e2fs_bsize, M_TEMP, M_WAITOK);
  171         bcopy((caddr_t)bap, (caddr_t)copy, (u_int)fs->e2fs_bsize);
  172         bzero((caddr_t)&bap[last + 1],
  173             (NINDIR(fs) - (last + 1)) * sizeof(e2fs_daddr_t));
  174         if (last == -1)
  175                 bp->b_flags |= B_INVAL;
  176         if (DOINGASYNC(vp)) {
  177                 bdwrite(bp);
  178         } else {
  179                 error = bwrite(bp);
  180                 if (error)
  181                         allerror = error;
  182         }
  183         bap = copy;
  184 
  185         /*
  186          * Recursively free totally unused blocks.
  187          */
  188         for (i = NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
  189             i--, nlbn += factor) {
  190                 nb = bap[i];
  191                 if (nb == 0)
  192                         continue;
  193                 if (level > SINGLE) {
  194                         if ((error = ext2_indirtrunc(ip, nlbn,
  195                             fsbtodb(fs, nb), (int32_t)-1, level - 1, &blkcount)) != 0)
  196                                 allerror = error;
  197                         blocksreleased += blkcount;
  198                 }
  199                 ext2_blkfree(ip, nb, fs->e2fs_bsize);
  200                 blocksreleased += nblocks;
  201         }
  202 
  203         /*
  204          * Recursively free last partial block.
  205          */
  206         if (level > SINGLE && lastbn >= 0) {
  207                 last = lastbn % factor;
  208                 nb = bap[i];
  209                 if (nb != 0) {
  210                         if ((error = ext2_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
  211                             last, level - 1, &blkcount)) != 0)
  212                                 allerror = error;
  213                         blocksreleased += blkcount;
  214                 }
  215         }
  216         free(copy, M_TEMP);
  217         *countp = blocksreleased;
  218         return (allerror);
  219 }
  220 
  221 /*
  222  * Truncate the inode oip to at most length size, freeing the
  223  * disk blocks.
  224  */
  225 static int
  226 ext2_ind_truncate(struct vnode *vp, off_t length, int flags, struct ucred *cred,
  227     struct thread *td)
  228 {
  229         struct vnode *ovp = vp;
  230         e4fs_daddr_t lastblock;
  231         struct inode *oip;
  232         e4fs_daddr_t bn, lbn, lastiblock[EXT2_NIADDR], indir_lbn[EXT2_NIADDR];
  233         uint32_t oldblks[EXT2_NDADDR + EXT2_NIADDR];
  234         uint32_t newblks[EXT2_NDADDR + EXT2_NIADDR];
  235         struct m_ext2fs *fs;
  236         struct buf *bp;
  237         int offset, size, level;
  238         e4fs_daddr_t count, nblocks, blocksreleased = 0;
  239         int error, i, allerror;
  240         off_t osize;
  241 #ifdef INVARIANTS
  242         struct bufobj *bo;
  243 #endif
  244 
  245         oip = VTOI(ovp);
  246 #ifdef INVARIANTS
  247         bo = &ovp->v_bufobj;
  248 #endif
  249 
  250         fs = oip->i_e2fs;
  251         osize = oip->i_size;
  252         /*
  253          * Lengthen the size of the file. We must ensure that the
  254          * last byte of the file is allocated. Since the smallest
  255          * value of osize is 0, length will be at least 1.
  256          */
  257         if (osize < length) {
  258                 if (length > oip->i_e2fs->e2fs_maxfilesize)
  259                         return (EFBIG);
  260                 vnode_pager_setsize(ovp, length);
  261                 offset = blkoff(fs, length - 1);
  262                 lbn = lblkno(fs, length - 1);
  263                 flags |= BA_CLRBUF;
  264                 error = ext2_balloc(oip, lbn, offset + 1, cred, &bp, flags);
  265                 if (error) {
  266                         vnode_pager_setsize(vp, osize);
  267                         return (error);
  268                 }
  269                 oip->i_size = length;
  270                 if (bp->b_bufsize == fs->e2fs_bsize)
  271                         bp->b_flags |= B_CLUSTEROK;
  272                 if (flags & IO_SYNC)
  273                         bwrite(bp);
  274                 else if (DOINGASYNC(ovp))
  275                         bdwrite(bp);
  276                 else
  277                         bawrite(bp);
  278                 oip->i_flag |= IN_CHANGE | IN_UPDATE;
  279                 return (ext2_update(ovp, !DOINGASYNC(ovp)));
  280         }
  281         /*
  282          * Shorten the size of the file. If the file is not being
  283          * truncated to a block boundary, the contents of the
  284          * partial block following the end of the file must be
  285          * zero'ed in case it ever become accessible again because
  286          * of subsequent file growth.
  287          */
  288         /* I don't understand the comment above */
  289         offset = blkoff(fs, length);
  290         if (offset == 0) {
  291                 oip->i_size = length;
  292         } else {
  293                 lbn = lblkno(fs, length);
  294                 flags |= BA_CLRBUF;
  295                 error = ext2_balloc(oip, lbn, offset, cred, &bp, flags);
  296                 if (error)
  297                         return (error);
  298                 oip->i_size = length;
  299                 size = blksize(fs, oip, lbn);
  300                 bzero((char *)bp->b_data + offset, (u_int)(size - offset));
  301                 allocbuf(bp, size);
  302                 if (bp->b_bufsize == fs->e2fs_bsize)
  303                         bp->b_flags |= B_CLUSTEROK;
  304                 if (flags & IO_SYNC)
  305                         bwrite(bp);
  306                 else if (DOINGASYNC(ovp))
  307                         bdwrite(bp);
  308                 else
  309                         bawrite(bp);
  310         }
  311         /*
  312          * Calculate index into inode's block list of
  313          * last direct and indirect blocks (if any)
  314          * which we want to keep.  Lastblock is -1 when
  315          * the file is truncated to 0.
  316          */
  317         lastblock = lblkno(fs, length + fs->e2fs_bsize - 1) - 1;
  318         lastiblock[SINGLE] = lastblock - EXT2_NDADDR;
  319         lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
  320         lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
  321         nblocks = btodb(fs->e2fs_bsize);
  322         /*
  323          * Update file and block pointers on disk before we start freeing
  324          * blocks.  If we crash before free'ing blocks below, the blocks
  325          * will be returned to the free list.  lastiblock values are also
  326          * normalized to -1 for calls to ext2_indirtrunc below.
  327          */
  328         for (level = TRIPLE; level >= SINGLE; level--) {
  329                 oldblks[EXT2_NDADDR + level] = oip->i_ib[level];
  330                 if (lastiblock[level] < 0) {
  331                         oip->i_ib[level] = 0;
  332                         lastiblock[level] = -1;
  333                 }
  334         }
  335         for (i = 0; i < EXT2_NDADDR; i++) {
  336                 oldblks[i] = oip->i_db[i];
  337                 if (i > lastblock)
  338                         oip->i_db[i] = 0;
  339         }
  340         oip->i_flag |= IN_CHANGE | IN_UPDATE;
  341         allerror = ext2_update(ovp, !DOINGASYNC(ovp));
  342 
  343         /*
  344          * Having written the new inode to disk, save its new configuration
  345          * and put back the old block pointers long enough to process them.
  346          * Note that we save the new block configuration so we can check it
  347          * when we are done.
  348          */
  349         for (i = 0; i < EXT2_NDADDR; i++) {
  350                 newblks[i] = oip->i_db[i];
  351                 oip->i_db[i] = oldblks[i];
  352         }
  353         for (i = 0; i < EXT2_NIADDR; i++) {
  354                 newblks[EXT2_NDADDR + i] = oip->i_ib[i];
  355                 oip->i_ib[i] = oldblks[EXT2_NDADDR + i];
  356         }
  357         oip->i_size = osize;
  358         error = vtruncbuf(ovp, cred, length, (int)fs->e2fs_bsize);
  359         if (error && (allerror == 0))
  360                 allerror = error;
  361         vnode_pager_setsize(ovp, length);
  362 
  363         /*
  364          * Indirect blocks first.
  365          */
  366         indir_lbn[SINGLE] = -EXT2_NDADDR;
  367         indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
  368         indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
  369         for (level = TRIPLE; level >= SINGLE; level--) {
  370                 bn = oip->i_ib[level];
  371                 if (bn != 0) {
  372                         error = ext2_indirtrunc(oip, indir_lbn[level],
  373                             fsbtodb(fs, bn), lastiblock[level], level, &count);
  374                         if (error)
  375                                 allerror = error;
  376                         blocksreleased += count;
  377                         if (lastiblock[level] < 0) {
  378                                 oip->i_ib[level] = 0;
  379                                 ext2_blkfree(oip, bn, fs->e2fs_fsize);
  380                                 blocksreleased += nblocks;
  381                         }
  382                 }
  383                 if (lastiblock[level] >= 0)
  384                         goto done;
  385         }
  386 
  387         /*
  388          * All whole direct blocks or frags.
  389          */
  390         for (i = EXT2_NDADDR - 1; i > lastblock; i--) {
  391                 long bsize;
  392 
  393                 bn = oip->i_db[i];
  394                 if (bn == 0)
  395                         continue;
  396                 oip->i_db[i] = 0;
  397                 bsize = blksize(fs, oip, i);
  398                 ext2_blkfree(oip, bn, bsize);
  399                 blocksreleased += btodb(bsize);
  400         }
  401         if (lastblock < 0)
  402                 goto done;
  403 
  404         /*
  405          * Finally, look for a change in size of the
  406          * last direct block; release any frags.
  407          */
  408         bn = oip->i_db[lastblock];
  409         if (bn != 0) {
  410                 long oldspace, newspace;
  411 
  412                 /*
  413                  * Calculate amount of space we're giving
  414                  * back as old block size minus new block size.
  415                  */
  416                 oldspace = blksize(fs, oip, lastblock);
  417                 oip->i_size = length;
  418                 newspace = blksize(fs, oip, lastblock);
  419                 if (newspace == 0)
  420                         panic("ext2_truncate: newspace");
  421                 if (oldspace - newspace > 0) {
  422                         /*
  423                          * Block number of space to be free'd is
  424                          * the old block # plus the number of frags
  425                          * required for the storage we're keeping.
  426                          */
  427                         bn += numfrags(fs, newspace);
  428                         ext2_blkfree(oip, bn, oldspace - newspace);
  429                         blocksreleased += btodb(oldspace - newspace);
  430                 }
  431         }
  432 done:
  433 #ifdef INVARIANTS
  434         for (level = SINGLE; level <= TRIPLE; level++)
  435                 if (newblks[EXT2_NDADDR + level] != oip->i_ib[level])
  436                         panic("itrunc1");
  437         for (i = 0; i < EXT2_NDADDR; i++)
  438                 if (newblks[i] != oip->i_db[i])
  439                         panic("itrunc2");
  440         BO_LOCK(bo);
  441         if (length == 0 && (bo->bo_dirty.bv_cnt != 0 ||
  442             bo->bo_clean.bv_cnt != 0))
  443                 panic("itrunc3");
  444         BO_UNLOCK(bo);
  445 #endif  /* INVARIANTS */
  446         /*
  447          * Put back the real size.
  448          */
  449         oip->i_size = length;
  450         if (oip->i_blocks >= blocksreleased)
  451                 oip->i_blocks -= blocksreleased;
  452         else                            /* sanity */
  453                 oip->i_blocks = 0;
  454         oip->i_flag |= IN_CHANGE;
  455         vnode_pager_setsize(ovp, length);
  456         return (allerror);
  457 }
  458 
  459 static int
  460 ext2_ext_truncate(struct vnode *vp, off_t length, int flags,
  461     struct ucred *cred, struct thread *td)
  462 {
  463         struct vnode *ovp = vp;
  464         int32_t lastblock;
  465         struct m_ext2fs *fs;
  466         struct inode *oip;
  467         struct buf *bp;
  468         uint32_t lbn, offset;
  469         int error, size;
  470         off_t osize;
  471 
  472         oip = VTOI(ovp);
  473         fs = oip->i_e2fs;
  474         osize = oip->i_size;
  475 
  476         if (osize < length) {
  477                 if (length > oip->i_e2fs->e2fs_maxfilesize) {
  478                         return (EFBIG);
  479                 }
  480                 vnode_pager_setsize(ovp, length);
  481                 offset = blkoff(fs, length - 1);
  482                 lbn = lblkno(fs, length - 1);
  483                 flags |= BA_CLRBUF;
  484                 error = ext2_balloc(oip, lbn, offset + 1, cred, &bp, flags);
  485                 if (error) {
  486                         vnode_pager_setsize(vp, osize);
  487                         return (error);
  488                 }
  489                 oip->i_size = length;
  490                 if (bp->b_bufsize == fs->e2fs_bsize)
  491                         bp->b_flags |= B_CLUSTEROK;
  492                 if (flags & IO_SYNC)
  493                         bwrite(bp);
  494                 else if (DOINGASYNC(ovp))
  495                         bdwrite(bp);
  496                 else
  497                         bawrite(bp);
  498                 oip->i_flag |= IN_CHANGE | IN_UPDATE;
  499                 return (ext2_update(ovp, !DOINGASYNC(ovp)));
  500         }
  501 
  502         lastblock = (length + fs->e2fs_bsize - 1) / fs->e2fs_bsize;
  503         error = ext4_ext_remove_space(oip, lastblock, flags, cred, td);
  504         if (error)
  505                 return (error);
  506 
  507         offset = blkoff(fs, length);
  508         if (offset == 0) {
  509                 oip->i_size = length;
  510         } else {
  511                 lbn = lblkno(fs, length);
  512                 flags |= BA_CLRBUF;
  513                 error = ext2_balloc(oip, lbn, offset, cred, &bp, flags);
  514                 if (error) {
  515                         return (error);
  516                 }
  517                 oip->i_size = length;
  518                 size = blksize(fs, oip, lbn);
  519                 bzero((char *)bp->b_data + offset, (u_int)(size - offset));
  520                 allocbuf(bp, size);
  521                 if (bp->b_bufsize == fs->e2fs_bsize)
  522                         bp->b_flags |= B_CLUSTEROK;
  523                 if (flags & IO_SYNC)
  524                         bwrite(bp);
  525                 else if (DOINGASYNC(ovp))
  526                         bdwrite(bp);
  527                 else
  528                         bawrite(bp);
  529         }
  530 
  531         oip->i_size = osize;
  532         error = vtruncbuf(ovp, cred, length, (int)fs->e2fs_bsize);
  533         if (error)
  534                 return (error);
  535 
  536         vnode_pager_setsize(ovp, length);
  537 
  538         oip->i_size = length;
  539         oip->i_flag |= IN_CHANGE | IN_UPDATE;
  540         error = ext2_update(ovp, !DOINGASYNC(ovp));
  541 
  542         return (error);
  543 }
  544 
  545 /*
  546  * Truncate the inode ip to at most length size, freeing the
  547  * disk blocks.
  548  */
  549 int
  550 ext2_truncate(struct vnode *vp, off_t length, int flags, struct ucred *cred,
  551     struct thread *td)
  552 {
  553         struct inode *ip;
  554         int error;
  555 
  556         ASSERT_VOP_LOCKED(vp, "ext2_truncate");
  557 
  558         if (length < 0)
  559                 return (EINVAL);
  560 
  561         ip = VTOI(vp);
  562         if (vp->v_type == VLNK &&
  563             ip->i_size < vp->v_mount->mnt_maxsymlinklen) {
  564 #ifdef INVARIANTS
  565                 if (length != 0)
  566                         panic("ext2_truncate: partial truncate of symlink");
  567 #endif
  568                 bzero((char *)&ip->i_shortlink, (u_int)ip->i_size);
  569                 ip->i_size = 0;
  570                 ip->i_flag |= IN_CHANGE | IN_UPDATE;
  571                 return (ext2_update(vp, 1));
  572         }
  573         if (ip->i_size == length) {
  574                 ip->i_flag |= IN_CHANGE | IN_UPDATE;
  575                 return (ext2_update(vp, 0));
  576         }
  577 
  578         if (ip->i_flag & IN_E4EXTENTS)
  579                 error = ext2_ext_truncate(vp, length, flags, cred, td);
  580         else
  581                 error = ext2_ind_truncate(vp, length, flags, cred, td);
  582 
  583         return (error);
  584 }
  585 
  586 /*
  587  *      discard preallocated blocks
  588  */
  589 int
  590 ext2_inactive(struct vop_inactive_args *ap)
  591 {
  592         struct vnode *vp = ap->a_vp;
  593         struct inode *ip = VTOI(vp);
  594         struct thread *td = ap->a_td;
  595         int mode, error = 0;
  596 
  597         /*
  598          * Ignore inodes related to stale file handles.
  599          */
  600         if (ip->i_mode == 0)
  601                 goto out;
  602         if (ip->i_nlink <= 0) {
  603                 ext2_extattr_free(ip);
  604                 error = ext2_truncate(vp, (off_t)0, 0, NOCRED, td);
  605                 if (!(ip->i_flag & IN_E4EXTENTS))
  606                         ip->i_rdev = 0;
  607                 mode = ip->i_mode;
  608                 ip->i_mode = 0;
  609                 ip->i_flag |= IN_CHANGE | IN_UPDATE;
  610                 ext2_vfree(vp, ip->i_number, mode);
  611         }
  612         if (ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE))
  613                 ext2_update(vp, 0);
  614 out:
  615         /*
  616          * If we are done with the inode, reclaim it
  617          * so that it can be reused immediately.
  618          */
  619         if (ip->i_mode == 0)
  620                 vrecycle(vp);
  621         return (error);
  622 }
  623 
  624 /*
  625  * Reclaim an inode so that it can be used for other purposes.
  626  */
  627 int
  628 ext2_reclaim(struct vop_reclaim_args *ap)
  629 {
  630         struct inode *ip;
  631         struct vnode *vp = ap->a_vp;
  632 
  633         ip = VTOI(vp);
  634         if (ip->i_flag & IN_LAZYMOD) {
  635                 ip->i_flag |= IN_MODIFIED;
  636                 ext2_update(vp, 0);
  637         }
  638         vfs_hash_remove(vp);
  639         free(vp->v_data, M_EXT2NODE);
  640         vp->v_data = 0;
  641         vnode_destroy_vobject(vp);
  642         return (0);
  643 }

Cache object: ec4c22c20ff8d212516595b6a506c3dd


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