xref: /netbsd-src/sys/ufs/ext2fs/ext2fs_inode.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: ext2fs_inode.c,v 1.62 2007/12/08 19:29:53 pooka 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 1.62 2007/12/08 19:29:53 pooka 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 	} */ *ap = v;
145 	struct vnode *vp = ap->a_vp;
146 	struct inode *ip = VTOI(vp);
147 	int error = 0;
148 
149 	if (prtactive && vp->v_usecount != 0)
150 		vprint("ext2fs_inactive: pushing active", vp);
151 	/* Get rid of inodes related to stale file handles. */
152 	if (ip->i_e2fs_mode == 0 || ip->i_e2fs_dtime != 0)
153 		goto out;
154 
155 	error = 0;
156 	if (ip->i_e2fs_nlink == 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
157 		if (ext2fs_size(ip) != 0) {
158 			error = ext2fs_truncate(vp, (off_t)0, 0, NOCRED);
159 		}
160 		ip->i_e2fs_dtime = time_second;
161 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
162 		ext2fs_vfree(vp, ip->i_number, ip->i_e2fs_mode);
163 	}
164 	if (ip->i_flag & (IN_CHANGE | IN_UPDATE | IN_MODIFIED)) {
165 		ext2fs_update(vp, NULL, NULL, 0);
166 	}
167 out:
168 	VOP_UNLOCK(vp, 0);
169 	/*
170 	 * If we are done with the inode, reclaim it
171 	 * so that it can be reused immediately.
172 	 */
173 	if (ip->i_e2fs_dtime != 0)
174 		vrecycle(vp, NULL, curlwp);
175 	return (error);
176 }
177 
178 
179 /*
180  * Update the access, modified, and inode change times as specified by the
181  * IACCESS, IUPDATE, and ICHANGE flags respectively. The IMODIFIED flag is
182  * used to specify that the inode needs to be updated but that the times have
183  * already been set. The access and modified times are taken from the second
184  * and third parameters; the inode change time is always taken from the current
185  * time. If UPDATE_WAIT or UPDATE_DIROP is set, then wait for the disk
186  * write of the inode to complete.
187  */
188 int
189 ext2fs_update(struct vnode *vp, const struct timespec *acc,
190     const struct timespec *mod, int updflags)
191 {
192 	struct m_ext2fs *fs;
193 	struct buf *bp;
194 	struct inode *ip;
195 	int error;
196 	void *cp;
197 	int flags;
198 
199 	if (vp->v_mount->mnt_flag & MNT_RDONLY)
200 		return (0);
201 	ip = VTOI(vp);
202 	EXT2FS_ITIMES(ip, acc, mod, NULL);
203 	if (updflags & UPDATE_CLOSE)
204 		flags = ip->i_flag & (IN_MODIFIED | IN_ACCESSED);
205 	else
206 		flags = ip->i_flag & IN_MODIFIED;
207 	if (flags == 0)
208 		return (0);
209 	fs = ip->i_e2fs;
210 
211 	error = bread(ip->i_devvp,
212 			  fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
213 			  (int)fs->e2fs_bsize, NOCRED, &bp);
214 	if (error) {
215 		brelse(bp, 0);
216 		return (error);
217 	}
218 	ip->i_flag &= ~(IN_MODIFIED | IN_ACCESSED);
219 	cp = (char *)bp->b_data +
220 	    (ino_to_fsbo(fs, ip->i_number) * EXT2_DINODE_SIZE);
221 	e2fs_isave(ip->i_din.e2fs_din, (struct ext2fs_dinode *)cp);
222 	if ((updflags & (UPDATE_WAIT|UPDATE_DIROP)) != 0 &&
223 	    (flags & IN_MODIFIED) != 0 &&
224 	    (vp->v_mount->mnt_flag & MNT_ASYNC) == 0)
225 		return (bwrite(bp));
226 	else {
227 		bdwrite(bp);
228 		return (0);
229 	}
230 }
231 
232 #define	SINGLE	0	/* index of single indirect block */
233 #define	DOUBLE	1	/* index of double indirect block */
234 #define	TRIPLE	2	/* index of triple indirect block */
235 /*
236  * Truncate the inode oip to at most length size, freeing the
237  * disk blocks.
238  */
239 int
240 ext2fs_truncate(struct vnode *ovp, off_t length, int ioflag,
241     kauth_cred_t cred)
242 {
243 	daddr_t lastblock;
244 	struct inode *oip = VTOI(ovp);
245 	daddr_t bn, lastiblock[NIADDR], indir_lbn[NIADDR];
246 	/* XXX ondisk32 */
247 	int32_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
248 	struct m_ext2fs *fs;
249 	int offset, size, level;
250 	long count, blocksreleased = 0;
251 	int i, nblocks;
252 	int error, allerror = 0;
253 	off_t osize;
254 	int sync;
255 	struct ufsmount *ump = oip->i_ump;
256 
257 	if (ovp->v_type == VCHR || ovp->v_type == VBLK ||
258 	    ovp->v_type == VFIFO || ovp->v_type == VSOCK) {
259 		return 0;
260 	}
261 
262 	if (length < 0)
263 		return (EINVAL);
264 
265 	if (ovp->v_type == VLNK &&
266 	    (ext2fs_size(oip) < ump->um_maxsymlinklen ||
267 	     (ump->um_maxsymlinklen == 0 && oip->i_e2fs_nblock == 0))) {
268 		KDASSERT(length == 0);
269 		memset((char *)&oip->i_din.e2fs_din->e2di_shortlink, 0,
270 			(u_int)ext2fs_size(oip));
271 		(void)ext2fs_setsize(oip, 0);
272 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
273 		return (ext2fs_update(ovp, NULL, NULL, 0));
274 	}
275 	if (ext2fs_size(oip) == length) {
276 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
277 		return (ext2fs_update(ovp, NULL, NULL, 0));
278 	}
279 	fs = oip->i_e2fs;
280 	if (length > ump->um_maxfilesize)
281 		return (EFBIG);
282 
283 	osize = ext2fs_size(oip);
284 
285 	/*
286 	 * Lengthen the size of the file. We must ensure that the
287 	 * last byte of the file is allocated. Since the smallest
288 	 * value of osize is 0, length will be at least 1.
289 	 */
290 	if (osize < length) {
291 		uvm_vnp_setwritesize(ovp, length);
292 		error = ufs_balloc_range(ovp, length - 1, 1, cred,
293 		    ioflag & IO_SYNC ? B_SYNC : 0);
294 		if (error) {
295 			(void) ext2fs_truncate(ovp, osize, ioflag & IO_SYNC,
296 			    cred);
297 			return (error);
298 		}
299 		uvm_vnp_setsize(ovp, length);
300 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
301 		KASSERT(error  || ovp->v_size == ext2fs_size(oip));
302 		return (ext2fs_update(ovp, NULL, NULL, 0));
303 	}
304 	/*
305 	 * Shorten the size of the file. If the file is not being
306 	 * truncated to a block boundry, the contents of the
307 	 * partial block following the end of the file must be
308 	 * zero'ed in case it ever become accessible again because
309 	 * of subsequent file growth.
310 	 */
311 	offset = blkoff(fs, length);
312 	if (offset != 0) {
313 		size = fs->e2fs_bsize;
314 
315 		/* XXXUBC we should handle more than just VREG */
316 		uvm_vnp_zerorange(ovp, length, size - offset);
317 	}
318 	(void)ext2fs_setsize(oip, length);
319 	uvm_vnp_setsize(ovp, length);
320 	/*
321 	 * Calculate index into inode's block list of
322 	 * last direct and indirect blocks (if any)
323 	 * which we want to keep.  Lastblock is -1 when
324 	 * the file is truncated to 0.
325 	 */
326 	lastblock = lblkno(fs, length + fs->e2fs_bsize - 1) - 1;
327 	lastiblock[SINGLE] = lastblock - NDADDR;
328 	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
329 	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
330 	nblocks = btodb(fs->e2fs_bsize);
331 	/*
332 	 * Update file and block pointers on disk before we start freeing
333 	 * blocks.  If we crash before free'ing blocks below, the blocks
334 	 * will be returned to the free list.  lastiblock values are also
335 	 * normalized to -1 for calls to ext2fs_indirtrunc below.
336 	 */
337 	memcpy((void *)oldblks, (void *)&oip->i_e2fs_blocks[0], sizeof oldblks);
338 	sync = 0;
339 	for (level = TRIPLE; level >= SINGLE; level--) {
340 		if (lastiblock[level] < 0 && oldblks[NDADDR + level] != 0) {
341 			sync = 1;
342 			oip->i_e2fs_blocks[NDADDR + level] = 0;
343 			lastiblock[level] = -1;
344 		}
345 	}
346 	for (i = 0; i < NDADDR; i++) {
347 		if (i > lastblock && oldblks[i] != 0) {
348 			sync = 1;
349 			oip->i_e2fs_blocks[i] = 0;
350 		}
351 	}
352 	oip->i_flag |= IN_CHANGE | IN_UPDATE;
353 	if (sync) {
354 		error = ext2fs_update(ovp, NULL, NULL, UPDATE_WAIT);
355 		if (error && !allerror)
356 			allerror = error;
357 	}
358 
359 	/*
360 	 * Having written the new inode to disk, save its new configuration
361 	 * and put back the old block pointers long enough to process them.
362 	 * Note that we save the new block configuration so we can check it
363 	 * when we are done.
364 	 */
365 	memcpy((void *)newblks, (void *)&oip->i_e2fs_blocks[0], sizeof newblks);
366 	memcpy((void *)&oip->i_e2fs_blocks[0], (void *)oldblks, sizeof oldblks);
367 
368 	(void)ext2fs_setsize(oip, osize);
369 	error = vtruncbuf(ovp, lastblock + 1, 0, 0);
370 	if (error && !allerror)
371 		allerror = error;
372 
373 	/*
374 	 * Indirect blocks first.
375 	 */
376 	indir_lbn[SINGLE] = -NDADDR;
377 	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) -1;
378 	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
379 	for (level = TRIPLE; level >= SINGLE; level--) {
380 		/* XXX ondisk32 */
381 		bn = fs2h32(oip->i_e2fs_blocks[NDADDR + level]);
382 		if (bn != 0) {
383 			error = ext2fs_indirtrunc(oip, indir_lbn[level],
384 			    fsbtodb(fs, bn), lastiblock[level], level, &count);
385 			if (error)
386 				allerror = error;
387 			blocksreleased += count;
388 			if (lastiblock[level] < 0) {
389 				oip->i_e2fs_blocks[NDADDR + level] = 0;
390 				ext2fs_blkfree(oip, bn);
391 				blocksreleased += nblocks;
392 			}
393 		}
394 		if (lastiblock[level] >= 0)
395 			goto done;
396 	}
397 
398 	/*
399 	 * All whole direct blocks or frags.
400 	 */
401 	for (i = NDADDR - 1; i > lastblock; i--) {
402 		/* XXX ondisk32 */
403 		bn = fs2h32(oip->i_e2fs_blocks[i]);
404 		if (bn == 0)
405 			continue;
406 		oip->i_e2fs_blocks[i] = 0;
407 		ext2fs_blkfree(oip, bn);
408 		blocksreleased += btodb(fs->e2fs_bsize);
409 	}
410 
411 done:
412 #ifdef DIAGNOSTIC
413 	for (level = SINGLE; level <= TRIPLE; level++)
414 		if (newblks[NDADDR + level] !=
415 		    oip->i_e2fs_blocks[NDADDR + level])
416 			panic("ext2fs_truncate1");
417 	for (i = 0; i < NDADDR; i++)
418 		if (newblks[i] != oip->i_e2fs_blocks[i])
419 			panic("ext2fs_truncate2");
420 	if (length == 0 &&
421 	    (!LIST_EMPTY(&ovp->v_cleanblkhd) ||
422 	     !LIST_EMPTY(&ovp->v_dirtyblkhd)))
423 		panic("ext2fs_truncate3");
424 #endif /* DIAGNOSTIC */
425 	/*
426 	 * Put back the real size.
427 	 */
428 	(void)ext2fs_setsize(oip, length);
429 	oip->i_e2fs_nblock -= blocksreleased;
430 	oip->i_flag |= IN_CHANGE;
431 	KASSERT(ovp->v_type != VREG || ovp->v_size == ext2fs_size(oip));
432 	return (allerror);
433 }
434 
435 /*
436  * Release blocks associated with the inode ip and stored in the indirect
437  * block bn.  Blocks are free'd in LIFO order up to (but not including)
438  * lastbn.  If level is greater than SINGLE, the block is an indirect block
439  * and recursive calls to indirtrunc must be used to cleanse other indirect
440  * blocks.
441  *
442  * NB: triple indirect blocks are untested.
443  */
444 static int
445 ext2fs_indirtrunc(struct inode *ip, daddr_t lbn, daddr_t dbn, daddr_t lastbn,
446 		int level, long *countp)
447 {
448 	int i;
449 	struct buf *bp;
450 	struct m_ext2fs *fs = ip->i_e2fs;
451 	int32_t *bap;	/* XXX ondisk32 */
452 	struct vnode *vp;
453 	daddr_t nb, nlbn, last;
454 	int32_t *copy = NULL;	/* XXX ondisk32 */
455 	long blkcount, factor;
456 	int nblocks, blocksreleased = 0;
457 	int error = 0, allerror = 0;
458 
459 	/*
460 	 * Calculate index in current block of last
461 	 * block to be kept.  -1 indicates the entire
462 	 * block so we need not calculate the index.
463 	 */
464 	factor = 1;
465 	for (i = SINGLE; i < level; i++)
466 		factor *= NINDIR(fs);
467 	last = lastbn;
468 	if (lastbn > 0)
469 		last /= factor;
470 	nblocks = btodb(fs->e2fs_bsize);
471 	/*
472 	 * Get buffer of block pointers, zero those entries corresponding
473 	 * to blocks to be free'd, and update on disk copy first.  Since
474 	 * double(triple) indirect before single(double) indirect, calls
475 	 * to bmap on these blocks will fail.  However, we already have
476 	 * the on disk address, so we have to set the b_blkno field
477 	 * explicitly instead of letting bread do everything for us.
478 	 */
479 	vp = ITOV(ip);
480 	bp = getblk(vp, lbn, (int)fs->e2fs_bsize, 0, 0);
481 	if (bp->b_flags & (B_DONE | B_DELWRI)) {
482 		/* Braces must be here in case trace evaluates to nothing. */
483 		trace(TR_BREADHIT, pack(vp, fs->e2fs_bsize), lbn);
484 	} else {
485 		trace(TR_BREADMISS, pack(vp, fs->e2fs_bsize), lbn);
486 		curproc->p_stats->p_ru.ru_inblock++;	/* pay for read */
487 		bp->b_flags |= B_READ;
488 		if (bp->b_bcount > bp->b_bufsize)
489 			panic("ext2fs_indirtrunc: bad buffer size");
490 		bp->b_blkno = dbn;
491 		VOP_STRATEGY(vp, bp);
492 		error = biowait(bp);
493 	}
494 	if (error) {
495 		brelse(bp, 0);
496 		*countp = 0;
497 		return (error);
498 	}
499 
500 	bap = (int32_t *)bp->b_data;	/* XXX ondisk32 */
501 	if (lastbn >= 0) {
502 		/* XXX ondisk32 */
503 		copy = malloc(fs->e2fs_bsize, M_TEMP, M_WAITOK);
504 		memcpy((void *)copy, (void *)bap, (u_int)fs->e2fs_bsize);
505 		memset((void *)&bap[last + 1], 0,
506 			(u_int)(NINDIR(fs) - (last + 1)) * sizeof (u_int32_t));
507 		error = bwrite(bp);
508 		if (error)
509 			allerror = error;
510 		bap = copy;
511 	}
512 
513 	/*
514 	 * Recursively free totally unused blocks.
515 	 */
516 	for (i = NINDIR(fs) - 1,
517 		nlbn = lbn + 1 - i * factor; i > last;
518 		i--, nlbn += factor) {
519 		/* XXX ondisk32 */
520 		nb = fs2h32(bap[i]);
521 		if (nb == 0)
522 			continue;
523 		if (level > SINGLE) {
524 			error = ext2fs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
525 						   (daddr_t)-1, level - 1,
526 						   &blkcount);
527 			if (error)
528 				allerror = error;
529 			blocksreleased += blkcount;
530 		}
531 		ext2fs_blkfree(ip, nb);
532 		blocksreleased += nblocks;
533 	}
534 
535 	/*
536 	 * Recursively free last partial block.
537 	 */
538 	if (level > SINGLE && lastbn >= 0) {
539 		last = lastbn % factor;
540 		/* XXX ondisk32 */
541 		nb = fs2h32(bap[i]);
542 		if (nb != 0) {
543 			error = ext2fs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
544 						   last, level - 1, &blkcount);
545 			if (error)
546 				allerror = error;
547 			blocksreleased += blkcount;
548 		}
549 	}
550 
551 	if (copy != NULL) {
552 		FREE(copy, M_TEMP);
553 	} else {
554 		brelse(bp, BC_INVAL);
555 	}
556 
557 	*countp = blocksreleased;
558 	return (allerror);
559 }
560