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ext2fs_inode.c revision 1.42
      1 /*	$NetBSD: ext2fs_inode.c,v 1.42 2004/08/14 14:32:04 mycroft 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 1.42 2004/08/14 14:32:04 mycroft 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 
     82 #include <ufs/ufs/inode.h>
     83 #include <ufs/ufs/ufsmount.h>
     84 #include <ufs/ufs/ufs_extern.h>
     85 
     86 #include <ufs/ext2fs/ext2fs.h>
     87 #include <ufs/ext2fs/ext2fs_extern.h>
     88 
     89 extern int prtactive;
     90 
     91 static int ext2fs_indirtrunc __P((struct inode *, daddr_t, daddr_t,
     92 				  daddr_t, int, long *));
     93 
     94 /*
     95  * Last reference to an inode.  If necessary, write or delete it.
     96  */
     97 int
     98 ext2fs_inactive(v)
     99 	void *v;
    100 {
    101 	struct vop_inactive_args /* {
    102 		struct vnode *a_vp;
    103 		struct proc *a_p;
    104 	} */ *ap = v;
    105 	struct vnode *vp = ap->a_vp;
    106 	struct inode *ip = VTOI(vp);
    107 	struct mount *mp;
    108 	struct proc *p = ap->a_p;
    109 	struct timespec ts;
    110 	int error = 0;
    111 
    112 	if (prtactive && vp->v_usecount != 0)
    113 		vprint("ext2fs_inactive: pushing active", vp);
    114 	/* Get rid of inodes related to stale file handles. */
    115 	if (ip->i_e2fs_mode == 0 || ip->i_e2fs_dtime != 0)
    116 		goto out;
    117 
    118 	error = 0;
    119 	if (ip->i_e2fs_nlink == 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
    120 		vn_start_write(vp, &mp, V_WAIT | V_LOWER);
    121 		if (ip->i_e2fs_size != 0) {
    122 			error = VOP_TRUNCATE(vp, (off_t)0, 0, NOCRED, NULL);
    123 		}
    124 		TIMEVAL_TO_TIMESPEC(&time, &ts);
    125 		ip->i_e2fs_dtime = ts.tv_sec;
    126 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
    127 		VOP_VFREE(vp, ip->i_number, ip->i_e2fs_mode);
    128 		vn_finished_write(mp, V_LOWER);
    129 	}
    130 	if (ip->i_flag & (IN_CHANGE | IN_UPDATE | IN_MODIFIED)) {
    131 		vn_start_write(vp, &mp, V_WAIT | V_LOWER);
    132 		VOP_UPDATE(vp, NULL, NULL, 0);
    133 		vn_finished_write(mp, V_LOWER);
    134 	}
    135 out:
    136 	VOP_UNLOCK(vp, 0);
    137 	/*
    138 	 * If we are done with the inode, reclaim it
    139 	 * so that it can be reused immediately.
    140 	 */
    141 	if (ip->i_e2fs_dtime != 0)
    142 		vrecycle(vp, NULL, p);
    143 	return (error);
    144 }
    145 
    146 
    147 /*
    148  * Update the access, modified, and inode change times as specified by the
    149  * IACCESS, IUPDATE, and ICHANGE flags respectively. The IMODIFIED flag is
    150  * used to specify that the inode needs to be updated but that the times have
    151  * already been set. The access and modified times are taken from the second
    152  * and third parameters; the inode change time is always taken from the current
    153  * time. If UPDATE_WAIT or UPDATE_DIROP is set, then wait for the disk
    154  * write of the inode to complete.
    155  */
    156 int
    157 ext2fs_update(v)
    158 	void *v;
    159 {
    160 	struct vop_update_args /* {
    161 		struct vnode *a_vp;
    162 		struct timespec *a_access;
    163 		struct timespec *a_modify;
    164 		int a_flags;
    165 	} */ *ap = v;
    166 	struct m_ext2fs *fs;
    167 	struct buf *bp;
    168 	struct inode *ip;
    169 	int error;
    170 	struct timespec ts;
    171 	caddr_t cp;
    172 	int flags;
    173 
    174 	if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)
    175 		return (0);
    176 	ip = VTOI(ap->a_vp);
    177 	TIMEVAL_TO_TIMESPEC(&time, &ts);
    178 	EXT2FS_ITIMES(ip,
    179 	    ap->a_access ? ap->a_access : &ts,
    180 	    ap->a_modify ? ap->a_modify : &ts, &ts);
    181 	if (ap->a_flags & UPDATE_CLOSE)
    182 		flags = ip->i_flag & (IN_MODIFIED | IN_ACCESSED);
    183 	else
    184 		flags = ip->i_flag & IN_MODIFIED;
    185 	if (flags == 0)
    186 		return (0);
    187 	fs = ip->i_e2fs;
    188 
    189 	error = bread(ip->i_devvp,
    190 			  fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
    191 			  (int)fs->e2fs_bsize, NOCRED, &bp);
    192 	if (error) {
    193 		brelse(bp);
    194 		return (error);
    195 	}
    196 	ip->i_flag &= ~(IN_MODIFIED | IN_ACCESSED);
    197 	cp = (caddr_t)bp->b_data +
    198 	    (ino_to_fsbo(fs, ip->i_number) * EXT2_DINODE_SIZE);
    199 	e2fs_isave(ip->i_din.e2fs_din, (struct ext2fs_dinode *)cp);
    200 	if ((ap->a_flags & (UPDATE_WAIT|UPDATE_DIROP)) != 0 &&
    201 	    (flags & IN_MODIFIED) != 0 &&
    202 	    (ap->a_vp->v_mount->mnt_flag & MNT_ASYNC) == 0)
    203 		return (bwrite(bp));
    204 	else {
    205 		bdwrite(bp);
    206 		return (0);
    207 	}
    208 }
    209 
    210 #define	SINGLE	0	/* index of single indirect block */
    211 #define	DOUBLE	1	/* index of double indirect block */
    212 #define	TRIPLE	2	/* index of triple indirect block */
    213 /*
    214  * Truncate the inode oip to at most length size, freeing the
    215  * disk blocks.
    216  */
    217 int
    218 ext2fs_truncate(v)
    219 	void *v;
    220 {
    221 	struct vop_truncate_args /* {
    222 		struct vnode *a_vp;
    223 		off_t a_length;
    224 		int a_flags;
    225 		struct ucred *a_cred;
    226 		struct proc *a_p;
    227 	} */ *ap = v;
    228 	struct vnode *ovp = ap->a_vp;
    229 	daddr_t lastblock;
    230 	struct inode *oip;
    231 	daddr_t bn, lastiblock[NIADDR], indir_lbn[NIADDR];
    232 	/* XXX ondisk32 */
    233 	int32_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
    234 	off_t length = ap->a_length;
    235 	struct m_ext2fs *fs;
    236 	int offset, size, level;
    237 	long count, nblocks, blocksreleased = 0;
    238 	int i;
    239 	int error, allerror = 0;
    240 	off_t osize;
    241 
    242 	if (length < 0)
    243 		return (EINVAL);
    244 
    245 	oip = VTOI(ovp);
    246 	if (ovp->v_type == VLNK &&
    247 		(oip->i_e2fs_size < ovp->v_mount->mnt_maxsymlinklen ||
    248 		 (ovp->v_mount->mnt_maxsymlinklen == 0 &&
    249 		  oip->i_e2fs_nblock == 0))) {
    250 #ifdef DIAGNOSTIC
    251 		if (length != 0)
    252 			panic("ext2fs_truncate: partial truncate of symlink");
    253 #endif
    254 		memset((char *)&oip->i_din.e2fs_din->e2di_shortlink, 0,
    255 			(u_int)oip->i_e2fs_size);
    256 		oip->i_e2fs_size = 0;
    257 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    258 		return (VOP_UPDATE(ovp, NULL, NULL, UPDATE_WAIT));
    259 	}
    260 	if (oip->i_e2fs_size == length) {
    261 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    262 		return (VOP_UPDATE(ovp, NULL, NULL, 0));
    263 	}
    264 	fs = oip->i_e2fs;
    265 	osize = oip->i_e2fs_size;
    266 	/*
    267 	 * Lengthen the size of the file. We must ensure that the
    268 	 * last byte of the file is allocated. Since the smallest
    269 	 * value of osize is 0, length will be at least 1.
    270 	 */
    271 	if (osize < length) {
    272 #if 0 /* XXX */
    273 		if (length > fs->fs_maxfilesize)
    274 			return (EFBIG);
    275 #endif
    276 		ufs_balloc_range(ovp, length - 1, 1, ap->a_cred,
    277 		    ap->a_flags & IO_SYNC ? B_SYNC : 0);
    278 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    279 		return (VOP_UPDATE(ovp, NULL, NULL, 1));
    280 	}
    281 	/*
    282 	 * Shorten the size of the file. If the file is not being
    283 	 * truncated to a block boundry, 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 	offset = blkoff(fs, length);
    289 	if (offset != 0) {
    290 		size = fs->e2fs_bsize;
    291 
    292 		/* XXXUBC we should handle more than just VREG */
    293 		uvm_vnp_zerorange(ovp, length, size - offset);
    294 	}
    295 	oip->i_e2fs_size = length;
    296 	uvm_vnp_setsize(ovp, length);
    297 
    298 	/*
    299 	 * Calculate index into inode's block list of
    300 	 * last direct and indirect blocks (if any)
    301 	 * which we want to keep.  Lastblock is -1 when
    302 	 * the file is truncated to 0.
    303 	 */
    304 	lastblock = lblkno(fs, length + fs->e2fs_bsize - 1) - 1;
    305 	lastiblock[SINGLE] = lastblock - NDADDR;
    306 	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
    307 	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
    308 	nblocks = btodb(fs->e2fs_bsize);
    309 	/*
    310 	 * Update file and block pointers on disk before we start freeing
    311 	 * blocks.  If we crash before free'ing blocks below, the blocks
    312 	 * will be returned to the free list.  lastiblock values are also
    313 	 * normalized to -1 for calls to ext2fs_indirtrunc below.
    314 	 */
    315 	memcpy((caddr_t)oldblks, (caddr_t)&oip->i_e2fs_blocks[0], sizeof oldblks);
    316 	for (level = TRIPLE; level >= SINGLE; level--)
    317 		if (lastiblock[level] < 0) {
    318 			oip->i_e2fs_blocks[NDADDR + level] = 0;
    319 			lastiblock[level] = -1;
    320 		}
    321 	for (i = NDADDR - 1; i > lastblock; i--)
    322 		oip->i_e2fs_blocks[i] = 0;
    323 	oip->i_flag |= IN_CHANGE | IN_UPDATE;
    324 	error = VOP_UPDATE(ovp, NULL, NULL, UPDATE_WAIT);
    325 	if (error && !allerror)
    326 		allerror = error;
    327 
    328 	/*
    329 	 * Having written the new inode to disk, save its new configuration
    330 	 * and put back the old block pointers long enough to process them.
    331 	 * Note that we save the new block configuration so we can check it
    332 	 * when we are done.
    333 	 */
    334 
    335 	memcpy((caddr_t)newblks, (caddr_t)&oip->i_e2fs_blocks[0], sizeof newblks);
    336 	memcpy((caddr_t)&oip->i_e2fs_blocks[0], (caddr_t)oldblks, sizeof oldblks);
    337 	oip->i_e2fs_size = osize;
    338 	error = vtruncbuf(ovp, lastblock + 1, 0, 0);
    339 	if (error && !allerror)
    340 		allerror = error;
    341 
    342 	/*
    343 	 * Indirect blocks first.
    344 	 */
    345 	indir_lbn[SINGLE] = -NDADDR;
    346 	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) -1;
    347 	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
    348 	for (level = TRIPLE; level >= SINGLE; level--) {
    349 		/* XXX ondisk32 */
    350 		bn = fs2h32(oip->i_e2fs_blocks[NDADDR + level]);
    351 		if (bn != 0) {
    352 			error = ext2fs_indirtrunc(oip, indir_lbn[level],
    353 			    fsbtodb(fs, bn), lastiblock[level], level, &count);
    354 			if (error)
    355 				allerror = error;
    356 			blocksreleased += count;
    357 			if (lastiblock[level] < 0) {
    358 				oip->i_e2fs_blocks[NDADDR + level] = 0;
    359 				ext2fs_blkfree(oip, bn);
    360 				blocksreleased += nblocks;
    361 			}
    362 		}
    363 		if (lastiblock[level] >= 0)
    364 			goto done;
    365 	}
    366 
    367 	/*
    368 	 * All whole direct blocks or frags.
    369 	 */
    370 	for (i = NDADDR - 1; i > lastblock; i--) {
    371 		/* XXX ondisk32 */
    372 		bn = fs2h32(oip->i_e2fs_blocks[i]);
    373 		if (bn == 0)
    374 			continue;
    375 		oip->i_e2fs_blocks[i] = 0;
    376 		ext2fs_blkfree(oip, bn);
    377 		blocksreleased += btodb(fs->e2fs_bsize);
    378 	}
    379 
    380 done:
    381 #ifdef DIAGNOSTIC
    382 	for (level = SINGLE; level <= TRIPLE; level++)
    383 		if (newblks[NDADDR + level] !=
    384 		    oip->i_e2fs_blocks[NDADDR + level])
    385 			panic("ext2fs_truncate1");
    386 	for (i = 0; i < NDADDR; i++)
    387 		if (newblks[i] != oip->i_e2fs_blocks[i])
    388 			panic("ext2fs_truncate2");
    389 	if (length == 0 &&
    390 	    (!LIST_EMPTY(&ovp->v_cleanblkhd) ||
    391 	     !LIST_EMPTY(&ovp->v_dirtyblkhd)))
    392 		panic("ext2fs_truncate3");
    393 #endif /* DIAGNOSTIC */
    394 	/*
    395 	 * Put back the real size.
    396 	 */
    397 	oip->i_e2fs_size = length;
    398 	oip->i_e2fs_nblock -= blocksreleased;
    399 	oip->i_flag |= IN_CHANGE;
    400 	return (allerror);
    401 }
    402 
    403 /*
    404  * Release blocks associated with the inode ip and stored in the indirect
    405  * block bn.  Blocks are free'd in LIFO order up to (but not including)
    406  * lastbn.  If level is greater than SINGLE, the block is an indirect block
    407  * and recursive calls to indirtrunc must be used to cleanse other indirect
    408  * blocks.
    409  *
    410  * NB: triple indirect blocks are untested.
    411  */
    412 static int
    413 ext2fs_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
    414 	struct inode *ip;
    415 	daddr_t lbn, lastbn;
    416 	daddr_t dbn;
    417 	int level;
    418 	long *countp;
    419 {
    420 	int i;
    421 	struct buf *bp;
    422 	struct m_ext2fs *fs = ip->i_e2fs;
    423 	int32_t *bap;	/* XXX ondisk32 */
    424 	struct vnode *vp;
    425 	daddr_t nb, nlbn, last;
    426 	int32_t *copy = NULL;	/* XXX ondisk32 */
    427 	long blkcount, factor;
    428 	int nblocks, blocksreleased = 0;
    429 	int error = 0, allerror = 0;
    430 
    431 	/*
    432 	 * Calculate index in current block of last
    433 	 * block to be kept.  -1 indicates the entire
    434 	 * block so we need not calculate the index.
    435 	 */
    436 	factor = 1;
    437 	for (i = SINGLE; i < level; i++)
    438 		factor *= NINDIR(fs);
    439 	last = lastbn;
    440 	if (lastbn > 0)
    441 		last /= factor;
    442 	nblocks = btodb(fs->e2fs_bsize);
    443 	/*
    444 	 * Get buffer of block pointers, zero those entries corresponding
    445 	 * to blocks to be free'd, and update on disk copy first.  Since
    446 	 * double(triple) indirect before single(double) indirect, calls
    447 	 * to bmap on these blocks will fail.  However, we already have
    448 	 * the on disk address, so we have to set the b_blkno field
    449 	 * explicitly instead of letting bread do everything for us.
    450 	 */
    451 	vp = ITOV(ip);
    452 	bp = getblk(vp, lbn, (int)fs->e2fs_bsize, 0, 0);
    453 	if (bp->b_flags & (B_DONE | B_DELWRI)) {
    454 		/* Braces must be here in case trace evaluates to nothing. */
    455 		trace(TR_BREADHIT, pack(vp, fs->e2fs_bsize), lbn);
    456 	} else {
    457 		trace(TR_BREADMISS, pack(vp, fs->e2fs_bsize), lbn);
    458 		curproc->p_stats->p_ru.ru_inblock++;	/* pay for read */
    459 		bp->b_flags |= B_READ;
    460 		if (bp->b_bcount > bp->b_bufsize)
    461 			panic("ext2fs_indirtrunc: bad buffer size");
    462 		bp->b_blkno = dbn;
    463 		VOP_STRATEGY(vp, bp);
    464 		error = biowait(bp);
    465 	}
    466 	if (error) {
    467 		brelse(bp);
    468 		*countp = 0;
    469 		return (error);
    470 	}
    471 
    472 	bap = (int32_t *)bp->b_data;	/* XXX ondisk32 */
    473 	if (lastbn >= 0) {
    474 		/* XXX ondisk32 */
    475 		MALLOC(copy, int32_t *, fs->e2fs_bsize, M_TEMP, M_WAITOK);
    476 		memcpy((caddr_t)copy, (caddr_t)bap, (u_int)fs->e2fs_bsize);
    477 		memset((caddr_t)&bap[last + 1], 0,
    478 			(u_int)(NINDIR(fs) - (last + 1)) * sizeof (u_int32_t));
    479 		error = bwrite(bp);
    480 		if (error)
    481 			allerror = error;
    482 		bap = copy;
    483 	}
    484 
    485 	/*
    486 	 * Recursively free totally unused blocks.
    487 	 */
    488 	for (i = NINDIR(fs) - 1,
    489 		nlbn = lbn + 1 - i * factor; i > last;
    490 		i--, nlbn += factor) {
    491 		/* XXX ondisk32 */
    492 		nb = fs2h32(bap[i]);
    493 		if (nb == 0)
    494 			continue;
    495 		if (level > SINGLE) {
    496 			error = ext2fs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
    497 						   (daddr_t)-1, level - 1,
    498 						   &blkcount);
    499 			if (error)
    500 				allerror = error;
    501 			blocksreleased += blkcount;
    502 		}
    503 		ext2fs_blkfree(ip, nb);
    504 		blocksreleased += nblocks;
    505 	}
    506 
    507 	/*
    508 	 * Recursively free last partial block.
    509 	 */
    510 	if (level > SINGLE && lastbn >= 0) {
    511 		last = lastbn % factor;
    512 		/* XXX ondisk32 */
    513 		nb = fs2h32(bap[i]);
    514 		if (nb != 0) {
    515 			error = ext2fs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
    516 						   last, level - 1, &blkcount);
    517 			if (error)
    518 				allerror = error;
    519 			blocksreleased += blkcount;
    520 		}
    521 	}
    522 
    523 	if (copy != NULL) {
    524 		FREE(copy, M_TEMP);
    525 	} else {
    526 		bp->b_flags |= B_INVAL;
    527 		brelse(bp);
    528 	}
    529 
    530 	*countp = blocksreleased;
    531 	return (allerror);
    532 }
    533