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ext2fs_inode.c revision 1.56
      1 /*	$NetBSD: ext2fs_inode.c,v 1.56 2006/12/09 22:07:48 chs Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1982, 1986, 1989, 1993
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  *
     31  *	@(#)ffs_inode.c	8.8 (Berkeley) 10/19/94
     32  * Modified for ext2fs by Manuel Bouyer.
     33  */
     34 
     35 /*
     36  * Copyright (c) 1997 Manuel Bouyer.
     37  *
     38  * Redistribution and use in source and binary forms, with or without
     39  * modification, are permitted provided that the following conditions
     40  * are met:
     41  * 1. Redistributions of source code must retain the above copyright
     42  *    notice, this list of conditions and the following disclaimer.
     43  * 2. Redistributions in binary form must reproduce the above copyright
     44  *    notice, this list of conditions and the following disclaimer in the
     45  *    documentation and/or other materials provided with the distribution.
     46  * 3. All advertising materials mentioning features or use of this software
     47  *    must display the following acknowledgement:
     48  *	This product includes software developed by Manuel Bouyer.
     49  * 4. The name of the author may not be used to endorse or promote products
     50  *    derived from this software without specific prior written permission.
     51  *
     52  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     53  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     54  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     55  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     56  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     57  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     58  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     59  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     60  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     61  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     62  *
     63  *	@(#)ffs_inode.c	8.8 (Berkeley) 10/19/94
     64  * Modified for ext2fs by Manuel Bouyer.
     65  */
     66 
     67 #include <sys/cdefs.h>
     68 __KERNEL_RCSID(0, "$NetBSD: ext2fs_inode.c,v 1.56 2006/12/09 22:07:48 chs Exp $");
     69 
     70 #include <sys/param.h>
     71 #include <sys/systm.h>
     72 #include <sys/mount.h>
     73 #include <sys/proc.h>
     74 #include <sys/file.h>
     75 #include <sys/buf.h>
     76 #include <sys/vnode.h>
     77 #include <sys/kernel.h>
     78 #include <sys/malloc.h>
     79 #include <sys/trace.h>
     80 #include <sys/resourcevar.h>
     81 #include <sys/kauth.h>
     82 
     83 #include <ufs/ufs/inode.h>
     84 #include <ufs/ufs/ufsmount.h>
     85 #include <ufs/ufs/ufs_extern.h>
     86 
     87 #include <ufs/ext2fs/ext2fs.h>
     88 #include <ufs/ext2fs/ext2fs_extern.h>
     89 
     90 extern int prtactive;
     91 
     92 static int ext2fs_indirtrunc(struct inode *, daddr_t, daddr_t,
     93 				  daddr_t, int, long *);
     94 
     95 /*
     96  * Get the size of an inode.
     97  */
     98 u_int64_t
     99 ext2fs_size(struct inode *ip)
    100 {
    101 	u_int64_t size = ip->i_e2fs_size;
    102 
    103 	if ((ip->i_e2fs_mode & IFMT) == IFREG)
    104 		size |= (u_int64_t)ip->i_e2fs_dacl << 32;
    105 	return size;
    106 }
    107 
    108 int
    109 ext2fs_setsize(struct inode *ip, u_int64_t size)
    110 {
    111 	if ((ip->i_e2fs_mode & IFMT) == IFREG ||
    112 	    ip->i_e2fs_mode == 0) {
    113 		ip->i_e2fs_dacl = size >> 32;
    114 		if (size >= 0x80000000U) {
    115 			struct m_ext2fs *fs = ip->i_e2fs;
    116 
    117 			if (fs->e2fs.e2fs_rev <= E2FS_REV0) {
    118 				/* Linux automagically upgrades to REV1 here! */
    119 				return EFBIG;
    120 			}
    121 			if (!(fs->e2fs.e2fs_features_rocompat
    122 			    & EXT2F_ROCOMPAT_LARGEFILE)) {
    123 				fs->e2fs.e2fs_features_rocompat |=
    124 				    EXT2F_ROCOMPAT_LARGEFILE;
    125 				fs->e2fs_fmod = 1;
    126 			}
    127 		}
    128 	} else if (size >= 0x80000000U)
    129 		return EFBIG;
    130 
    131 	ip->i_e2fs_size = size;
    132 
    133 	return 0;
    134 }
    135 
    136 /*
    137  * Last reference to an inode.  If necessary, write or delete it.
    138  */
    139 int
    140 ext2fs_inactive(void *v)
    141 {
    142 	struct vop_inactive_args /* {
    143 		struct vnode *a_vp;
    144 		struct lwp *a_l;
    145 	} */ *ap = v;
    146 	struct vnode *vp = ap->a_vp;
    147 	struct inode *ip = VTOI(vp);
    148 	struct mount *mp;
    149 	struct lwp *l = ap->a_l;
    150 	int error = 0;
    151 
    152 	if (prtactive && vp->v_usecount != 0)
    153 		vprint("ext2fs_inactive: pushing active", vp);
    154 	/* Get rid of inodes related to stale file handles. */
    155 	if (ip->i_e2fs_mode == 0 || ip->i_e2fs_dtime != 0)
    156 		goto out;
    157 
    158 	error = 0;
    159 	if (ip->i_e2fs_nlink == 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
    160 		vn_start_write(vp, &mp, V_WAIT | V_LOWER);
    161 		if (ext2fs_size(ip) != 0) {
    162 			error = ext2fs_truncate(vp, (off_t)0, 0, NOCRED, NULL);
    163 		}
    164 		ip->i_e2fs_dtime = time_second;
    165 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
    166 		ext2fs_vfree(vp, ip->i_number, ip->i_e2fs_mode);
    167 		vn_finished_write(mp, V_LOWER);
    168 	}
    169 	if (ip->i_flag & (IN_CHANGE | IN_UPDATE | IN_MODIFIED)) {
    170 		vn_start_write(vp, &mp, V_WAIT | V_LOWER);
    171 		ext2fs_update(vp, NULL, NULL, 0);
    172 		vn_finished_write(mp, V_LOWER);
    173 	}
    174 out:
    175 	VOP_UNLOCK(vp, 0);
    176 	/*
    177 	 * If we are done with the inode, reclaim it
    178 	 * so that it can be reused immediately.
    179 	 */
    180 	if (ip->i_e2fs_dtime != 0)
    181 		vrecycle(vp, NULL, l);
    182 	return (error);
    183 }
    184 
    185 
    186 /*
    187  * Update the access, modified, and inode change times as specified by the
    188  * IACCESS, IUPDATE, and ICHANGE flags respectively. The IMODIFIED flag is
    189  * used to specify that the inode needs to be updated but that the times have
    190  * already been set. The access and modified times are taken from the second
    191  * and third parameters; the inode change time is always taken from the current
    192  * time. If UPDATE_WAIT or UPDATE_DIROP is set, then wait for the disk
    193  * write of the inode to complete.
    194  */
    195 int
    196 ext2fs_update(struct vnode *vp, const struct timespec *acc,
    197     const struct timespec *mod, int updflags)
    198 {
    199 	struct m_ext2fs *fs;
    200 	struct buf *bp;
    201 	struct inode *ip;
    202 	int error;
    203 	caddr_t cp;
    204 	int flags;
    205 
    206 	if (vp->v_mount->mnt_flag & MNT_RDONLY)
    207 		return (0);
    208 	ip = VTOI(vp);
    209 	EXT2FS_ITIMES(ip, acc, mod, NULL);
    210 	if (updflags & UPDATE_CLOSE)
    211 		flags = ip->i_flag & (IN_MODIFIED | IN_ACCESSED);
    212 	else
    213 		flags = ip->i_flag & IN_MODIFIED;
    214 	if (flags == 0)
    215 		return (0);
    216 	fs = ip->i_e2fs;
    217 
    218 	error = bread(ip->i_devvp,
    219 			  fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
    220 			  (int)fs->e2fs_bsize, NOCRED, &bp);
    221 	if (error) {
    222 		brelse(bp);
    223 		return (error);
    224 	}
    225 	ip->i_flag &= ~(IN_MODIFIED | IN_ACCESSED);
    226 	cp = (caddr_t)bp->b_data +
    227 	    (ino_to_fsbo(fs, ip->i_number) * EXT2_DINODE_SIZE);
    228 	e2fs_isave(ip->i_din.e2fs_din, (struct ext2fs_dinode *)cp);
    229 	if ((updflags & (UPDATE_WAIT|UPDATE_DIROP)) != 0 &&
    230 	    (flags & IN_MODIFIED) != 0 &&
    231 	    (vp->v_mount->mnt_flag & MNT_ASYNC) == 0)
    232 		return (bwrite(bp));
    233 	else {
    234 		bdwrite(bp);
    235 		return (0);
    236 	}
    237 }
    238 
    239 #define	SINGLE	0	/* index of single indirect block */
    240 #define	DOUBLE	1	/* index of double indirect block */
    241 #define	TRIPLE	2	/* index of triple indirect block */
    242 /*
    243  * Truncate the inode oip to at most length size, freeing the
    244  * disk blocks.
    245  */
    246 int
    247 ext2fs_truncate(struct vnode *ovp, off_t length, int ioflag,
    248     kauth_cred_t cred, struct proc *p)
    249 {
    250 	daddr_t lastblock;
    251 	struct inode *oip = VTOI(ovp);
    252 	daddr_t bn, lastiblock[NIADDR], indir_lbn[NIADDR];
    253 	/* XXX ondisk32 */
    254 	int32_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
    255 	struct m_ext2fs *fs;
    256 	int offset, size, level;
    257 	long count, blocksreleased = 0;
    258 	int i, nblocks;
    259 	int error, allerror = 0;
    260 	off_t osize;
    261 	int sync;
    262 	struct ufsmount *ump = oip->i_ump;
    263 
    264 	if (ovp->v_type == VCHR || ovp->v_type == VBLK ||
    265 	    ovp->v_type == VFIFO || ovp->v_type == VSOCK) {
    266 		return 0;
    267 	}
    268 
    269 	if (length < 0)
    270 		return (EINVAL);
    271 
    272 	if (ovp->v_type == VLNK &&
    273 	    (ext2fs_size(oip) < ump->um_maxsymlinklen ||
    274 	     (ump->um_maxsymlinklen == 0 && oip->i_e2fs_nblock == 0))) {
    275 		KDASSERT(length == 0);
    276 		memset((char *)&oip->i_din.e2fs_din->e2di_shortlink, 0,
    277 			(u_int)ext2fs_size(oip));
    278 		(void)ext2fs_setsize(oip, 0);
    279 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    280 		return (ext2fs_update(ovp, NULL, NULL, 0));
    281 	}
    282 	if (ext2fs_size(oip) == length) {
    283 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    284 		return (ext2fs_update(ovp, NULL, NULL, 0));
    285 	}
    286 	fs = oip->i_e2fs;
    287 	if (length > ump->um_maxfilesize)
    288 		return (EFBIG);
    289 
    290 	osize = ext2fs_size(oip);
    291 
    292 	/*
    293 	 * Lengthen the size of the file. We must ensure that the
    294 	 * last byte of the file is allocated. Since the smallest
    295 	 * value of osize is 0, length will be at least 1.
    296 	 */
    297 	if (osize < length) {
    298 		error = ufs_balloc_range(ovp, length - 1, 1, cred,
    299 		    ioflag & IO_SYNC ? B_SYNC : 0);
    300 		if (error) {
    301 			(void) ext2fs_truncate(ovp, osize, ioflag & IO_SYNC,
    302 			    cred, p);
    303 			return (error);
    304 		}
    305 		uvm_vnp_setsize(ovp, length);
    306 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    307 		KASSERT(error  || ovp->v_size == ext2fs_size(oip));
    308 		return (ext2fs_update(ovp, NULL, NULL, 0));
    309 	}
    310 	/*
    311 	 * Shorten the size of the file. If the file is not being
    312 	 * truncated to a block boundry, the contents of the
    313 	 * partial block following the end of the file must be
    314 	 * zero'ed in case it ever become accessible again because
    315 	 * of subsequent file growth.
    316 	 */
    317 	offset = blkoff(fs, length);
    318 	if (offset != 0) {
    319 		size = fs->e2fs_bsize;
    320 
    321 		/* XXXUBC we should handle more than just VREG */
    322 		uvm_vnp_zerorange(ovp, length, size - offset);
    323 	}
    324 	(void)ext2fs_setsize(oip, length);
    325 	uvm_vnp_setsize(ovp, length);
    326 	/*
    327 	 * Calculate index into inode's block list of
    328 	 * last direct and indirect blocks (if any)
    329 	 * which we want to keep.  Lastblock is -1 when
    330 	 * the file is truncated to 0.
    331 	 */
    332 	lastblock = lblkno(fs, length + fs->e2fs_bsize - 1) - 1;
    333 	lastiblock[SINGLE] = lastblock - NDADDR;
    334 	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
    335 	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
    336 	nblocks = btodb(fs->e2fs_bsize);
    337 	/*
    338 	 * Update file and block pointers on disk before we start freeing
    339 	 * blocks.  If we crash before free'ing blocks below, the blocks
    340 	 * will be returned to the free list.  lastiblock values are also
    341 	 * normalized to -1 for calls to ext2fs_indirtrunc below.
    342 	 */
    343 	memcpy((caddr_t)oldblks, (caddr_t)&oip->i_e2fs_blocks[0], sizeof oldblks);
    344 	sync = 0;
    345 	for (level = TRIPLE; level >= SINGLE; level--) {
    346 		if (lastiblock[level] < 0 && oldblks[NDADDR + level] != 0) {
    347 			sync = 1;
    348 			oip->i_e2fs_blocks[NDADDR + level] = 0;
    349 			lastiblock[level] = -1;
    350 		}
    351 	}
    352 	for (i = 0; i < NDADDR; i++) {
    353 		if (i > lastblock && oldblks[i] != 0) {
    354 			sync = 1;
    355 			oip->i_e2fs_blocks[i] = 0;
    356 		}
    357 	}
    358 	oip->i_flag |= IN_CHANGE | IN_UPDATE;
    359 	if (sync) {
    360 		error = ext2fs_update(ovp, NULL, NULL, UPDATE_WAIT);
    361 		if (error && !allerror)
    362 			allerror = error;
    363 	}
    364 
    365 	/*
    366 	 * Having written the new inode to disk, save its new configuration
    367 	 * and put back the old block pointers long enough to process them.
    368 	 * Note that we save the new block configuration so we can check it
    369 	 * when we are done.
    370 	 */
    371 	memcpy((caddr_t)newblks, (caddr_t)&oip->i_e2fs_blocks[0], sizeof newblks);
    372 	memcpy((caddr_t)&oip->i_e2fs_blocks[0], (caddr_t)oldblks, sizeof oldblks);
    373 
    374 	(void)ext2fs_setsize(oip, osize);
    375 	error = vtruncbuf(ovp, lastblock + 1, 0, 0);
    376 	if (error && !allerror)
    377 		allerror = error;
    378 
    379 	/*
    380 	 * Indirect blocks first.
    381 	 */
    382 	indir_lbn[SINGLE] = -NDADDR;
    383 	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) -1;
    384 	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
    385 	for (level = TRIPLE; level >= SINGLE; level--) {
    386 		/* XXX ondisk32 */
    387 		bn = fs2h32(oip->i_e2fs_blocks[NDADDR + level]);
    388 		if (bn != 0) {
    389 			error = ext2fs_indirtrunc(oip, indir_lbn[level],
    390 			    fsbtodb(fs, bn), lastiblock[level], level, &count);
    391 			if (error)
    392 				allerror = error;
    393 			blocksreleased += count;
    394 			if (lastiblock[level] < 0) {
    395 				oip->i_e2fs_blocks[NDADDR + level] = 0;
    396 				ext2fs_blkfree(oip, bn);
    397 				blocksreleased += nblocks;
    398 			}
    399 		}
    400 		if (lastiblock[level] >= 0)
    401 			goto done;
    402 	}
    403 
    404 	/*
    405 	 * All whole direct blocks or frags.
    406 	 */
    407 	for (i = NDADDR - 1; i > lastblock; i--) {
    408 		/* XXX ondisk32 */
    409 		bn = fs2h32(oip->i_e2fs_blocks[i]);
    410 		if (bn == 0)
    411 			continue;
    412 		oip->i_e2fs_blocks[i] = 0;
    413 		ext2fs_blkfree(oip, bn);
    414 		blocksreleased += btodb(fs->e2fs_bsize);
    415 	}
    416 
    417 done:
    418 #ifdef DIAGNOSTIC
    419 	for (level = SINGLE; level <= TRIPLE; level++)
    420 		if (newblks[NDADDR + level] !=
    421 		    oip->i_e2fs_blocks[NDADDR + level])
    422 			panic("ext2fs_truncate1");
    423 	for (i = 0; i < NDADDR; i++)
    424 		if (newblks[i] != oip->i_e2fs_blocks[i])
    425 			panic("ext2fs_truncate2");
    426 	if (length == 0 &&
    427 	    (!LIST_EMPTY(&ovp->v_cleanblkhd) ||
    428 	     !LIST_EMPTY(&ovp->v_dirtyblkhd)))
    429 		panic("ext2fs_truncate3");
    430 #endif /* DIAGNOSTIC */
    431 	/*
    432 	 * Put back the real size.
    433 	 */
    434 	(void)ext2fs_setsize(oip, length);
    435 	oip->i_e2fs_nblock -= blocksreleased;
    436 	oip->i_flag |= IN_CHANGE;
    437 	KASSERT(ovp->v_type != VREG || ovp->v_size == ext2fs_size(oip));
    438 	return (allerror);
    439 }
    440 
    441 /*
    442  * Release blocks associated with the inode ip and stored in the indirect
    443  * block bn.  Blocks are free'd in LIFO order up to (but not including)
    444  * lastbn.  If level is greater than SINGLE, the block is an indirect block
    445  * and recursive calls to indirtrunc must be used to cleanse other indirect
    446  * blocks.
    447  *
    448  * NB: triple indirect blocks are untested.
    449  */
    450 static int
    451 ext2fs_indirtrunc(struct inode *ip, daddr_t lbn, daddr_t dbn, daddr_t lastbn,
    452 		int level, long *countp)
    453 {
    454 	int i;
    455 	struct buf *bp;
    456 	struct m_ext2fs *fs = ip->i_e2fs;
    457 	int32_t *bap;	/* XXX ondisk32 */
    458 	struct vnode *vp;
    459 	daddr_t nb, nlbn, last;
    460 	int32_t *copy = NULL;	/* XXX ondisk32 */
    461 	long blkcount, factor;
    462 	int nblocks, blocksreleased = 0;
    463 	int error = 0, allerror = 0;
    464 
    465 	/*
    466 	 * Calculate index in current block of last
    467 	 * block to be kept.  -1 indicates the entire
    468 	 * block so we need not calculate the index.
    469 	 */
    470 	factor = 1;
    471 	for (i = SINGLE; i < level; i++)
    472 		factor *= NINDIR(fs);
    473 	last = lastbn;
    474 	if (lastbn > 0)
    475 		last /= factor;
    476 	nblocks = btodb(fs->e2fs_bsize);
    477 	/*
    478 	 * Get buffer of block pointers, zero those entries corresponding
    479 	 * to blocks to be free'd, and update on disk copy first.  Since
    480 	 * double(triple) indirect before single(double) indirect, calls
    481 	 * to bmap on these blocks will fail.  However, we already have
    482 	 * the on disk address, so we have to set the b_blkno field
    483 	 * explicitly instead of letting bread do everything for us.
    484 	 */
    485 	vp = ITOV(ip);
    486 	bp = getblk(vp, lbn, (int)fs->e2fs_bsize, 0, 0);
    487 	if (bp->b_flags & (B_DONE | B_DELWRI)) {
    488 		/* Braces must be here in case trace evaluates to nothing. */
    489 		trace(TR_BREADHIT, pack(vp, fs->e2fs_bsize), lbn);
    490 	} else {
    491 		trace(TR_BREADMISS, pack(vp, fs->e2fs_bsize), lbn);
    492 		curproc->p_stats->p_ru.ru_inblock++;	/* pay for read */
    493 		bp->b_flags |= B_READ;
    494 		if (bp->b_bcount > bp->b_bufsize)
    495 			panic("ext2fs_indirtrunc: bad buffer size");
    496 		bp->b_blkno = dbn;
    497 		VOP_STRATEGY(vp, bp);
    498 		error = biowait(bp);
    499 	}
    500 	if (error) {
    501 		brelse(bp);
    502 		*countp = 0;
    503 		return (error);
    504 	}
    505 
    506 	bap = (int32_t *)bp->b_data;	/* XXX ondisk32 */
    507 	if (lastbn >= 0) {
    508 		/* XXX ondisk32 */
    509 		copy = malloc(fs->e2fs_bsize, M_TEMP, M_WAITOK);
    510 		memcpy((caddr_t)copy, (caddr_t)bap, (u_int)fs->e2fs_bsize);
    511 		memset((caddr_t)&bap[last + 1], 0,
    512 			(u_int)(NINDIR(fs) - (last + 1)) * sizeof (u_int32_t));
    513 		error = bwrite(bp);
    514 		if (error)
    515 			allerror = error;
    516 		bap = copy;
    517 	}
    518 
    519 	/*
    520 	 * Recursively free totally unused blocks.
    521 	 */
    522 	for (i = NINDIR(fs) - 1,
    523 		nlbn = lbn + 1 - i * factor; i > last;
    524 		i--, nlbn += factor) {
    525 		/* XXX ondisk32 */
    526 		nb = fs2h32(bap[i]);
    527 		if (nb == 0)
    528 			continue;
    529 		if (level > SINGLE) {
    530 			error = ext2fs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
    531 						   (daddr_t)-1, level - 1,
    532 						   &blkcount);
    533 			if (error)
    534 				allerror = error;
    535 			blocksreleased += blkcount;
    536 		}
    537 		ext2fs_blkfree(ip, nb);
    538 		blocksreleased += nblocks;
    539 	}
    540 
    541 	/*
    542 	 * Recursively free last partial block.
    543 	 */
    544 	if (level > SINGLE && lastbn >= 0) {
    545 		last = lastbn % factor;
    546 		/* XXX ondisk32 */
    547 		nb = fs2h32(bap[i]);
    548 		if (nb != 0) {
    549 			error = ext2fs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
    550 						   last, level - 1, &blkcount);
    551 			if (error)
    552 				allerror = error;
    553 			blocksreleased += blkcount;
    554 		}
    555 	}
    556 
    557 	if (copy != NULL) {
    558 		FREE(copy, M_TEMP);
    559 	} else {
    560 		bp->b_flags |= B_INVAL;
    561 		brelse(bp);
    562 	}
    563 
    564 	*countp = blocksreleased;
    565 	return (allerror);
    566 }
    567