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ffs_inode.c revision 1.24.2.3
      1 /*	$NetBSD: ffs_inode.c,v 1.24.2.3 1999/05/30 15:04:34 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. All advertising materials mentioning features or use of this software
     16  *    must display the following acknowledgement:
     17  *	This product includes software developed by the University of
     18  *	California, Berkeley and its contributors.
     19  * 4. Neither the name of the University nor the names of its contributors
     20  *    may be used to endorse or promote products derived from this software
     21  *    without specific prior written permission.
     22  *
     23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     33  * SUCH DAMAGE.
     34  *
     35  *	@(#)ffs_inode.c	8.13 (Berkeley) 4/21/95
     36  */
     37 
     38 #if defined(_KERNEL) && !defined(_LKM)
     39 #include "opt_quota.h"
     40 #include "opt_uvm.h"
     41 #endif
     42 
     43 #include <sys/param.h>
     44 #include <sys/systm.h>
     45 #include <sys/mount.h>
     46 #include <sys/proc.h>
     47 #include <sys/file.h>
     48 #include <sys/buf.h>
     49 #include <sys/vnode.h>
     50 #include <sys/kernel.h>
     51 #include <sys/malloc.h>
     52 #include <sys/trace.h>
     53 #include <sys/resourcevar.h>
     54 
     55 #include <vm/vm.h>
     56 
     57 #if defined(UVM)
     58 #include <uvm/uvm_extern.h>
     59 #endif
     60 
     61 #include <ufs/ufs/quota.h>
     62 #include <ufs/ufs/inode.h>
     63 #include <ufs/ufs/ufsmount.h>
     64 #include <ufs/ufs/ufs_extern.h>
     65 #include <ufs/ufs/ufs_bswap.h>
     66 
     67 #include <ufs/ffs/fs.h>
     68 #include <ufs/ffs/ffs_extern.h>
     69 
     70 static int ffs_indirtrunc __P((struct inode *, ufs_daddr_t, ufs_daddr_t,
     71 			       ufs_daddr_t, int, long *));
     72 
     73 /*
     74  * Update the access, modified, and inode change times as specified
     75  * by the IN_ACCESS, IN_UPDATE, and IN_CHANGE flags respectively.
     76  * The IN_MODIFIED flag is used to specify that the inode needs to be
     77  * updated but that the times have already been set. The access
     78  * and modified times are taken from the second and third parameters;
     79  * the inode change time is always taken from the current time. If
     80  * waitfor is set, then wait for the disk write of the inode to
     81  * complete.
     82  */
     83 
     84 int
     85 ffs_update(v)
     86 	void *v;
     87 {
     88 	struct vop_update_args /* {
     89 		struct vnode *a_vp;
     90 		struct timespec *a_access;
     91 		struct timespec *a_modify;
     92 		int a_waitfor;
     93 	} */ *ap = v;
     94 	register struct fs *fs;
     95 	struct buf *bp;
     96 	struct inode *ip;
     97 	int error;
     98 	struct timespec ts;
     99 	caddr_t cp;
    100 
    101 	if (ap->a_vp->v_mount->mnt_flag & MNT_RDONLY)
    102 		return (0);
    103 	ip = VTOI(ap->a_vp);
    104 	TIMEVAL_TO_TIMESPEC(&time, &ts);
    105 	FFS_ITIMES(ip, ap->a_access, ap->a_modify, &ts);
    106 	if ((ip->i_flag & IN_MODIFIED) == 0)
    107 		return (0);
    108 	ip->i_flag &= ~IN_MODIFIED;
    109 	fs = ip->i_fs;
    110 	/*
    111 	 * Ensure that uid and gid are correct. This is a temporary
    112 	 * fix until fsck has been changed to do the update.
    113 	 */
    114 	if (fs->fs_inodefmt < FS_44INODEFMT) {			/* XXX */
    115 		ip->i_din.ffs_din.di_ouid = ip->i_ffs_uid;	/* XXX */
    116 		ip->i_din.ffs_din.di_ogid = ip->i_ffs_gid;	/* XXX */
    117 	}							/* XXX */
    118 	error = bread(ip->i_devvp,
    119 		      fsbtodb(fs, ino_to_fsba(fs, ip->i_number)),
    120 		      (int)fs->fs_bsize, NOCRED, &bp);
    121 	if (error) {
    122 		brelse(bp);
    123 		return (error);
    124 	}
    125 	cp = (caddr_t)bp->b_data +
    126 	    (ino_to_fsbo(fs, ip->i_number) * DINODE_SIZE);
    127 #ifdef FFS_EI
    128 	if (UFS_MPNEEDSWAP(ap->a_vp->v_mount))
    129 		ffs_dinode_swap(&ip->i_din.ffs_din, (struct dinode *)cp);
    130 	else
    131 #endif
    132 		memcpy(cp, &ip->i_din.ffs_din, DINODE_SIZE);
    133 	if (ap->a_waitfor && (ap->a_vp->v_mount->mnt_flag & MNT_ASYNC) == 0)
    134 		return (bwrite(bp));
    135 	else {
    136 		bdwrite(bp);
    137 		return (0);
    138 	}
    139 }
    140 
    141 #define	SINGLE	0	/* index of single indirect block */
    142 #define	DOUBLE	1	/* index of double indirect block */
    143 #define	TRIPLE	2	/* index of triple indirect block */
    144 /*
    145  * Truncate the inode oip to at most length size, freeing the
    146  * disk blocks.
    147  */
    148 int
    149 ffs_truncate(v)
    150 	void *v;
    151 {
    152 	struct vop_truncate_args /* {
    153 		struct vnode *a_vp;
    154 		off_t a_length;
    155 		int a_flags;
    156 		struct ucred *a_cred;
    157 		struct proc *a_p;
    158 	} */ *ap = v;
    159 	register struct vnode *ovp = ap->a_vp;
    160 	register ufs_daddr_t lastblock;
    161 	register struct inode *oip;
    162 	ufs_daddr_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
    163 	ufs_daddr_t oldblks[NDADDR + NIADDR], newblks[NDADDR + NIADDR];
    164 	off_t length = ap->a_length;
    165 	register struct fs *fs;
    166 	struct buf *bp;
    167 	int offset, size, level;
    168 	long count, nblocks, vflags, blocksreleased = 0;
    169 	struct timespec ts;
    170 	register int i;
    171 	int aflags, error, allerror;
    172 	off_t osize;
    173 
    174 	if (length < 0)
    175 		return (EINVAL);
    176 	oip = VTOI(ovp);
    177 	TIMEVAL_TO_TIMESPEC(&time, &ts);
    178 	if (ovp->v_type == VLNK &&
    179 	    (oip->i_ffs_size < ovp->v_mount->mnt_maxsymlinklen ||
    180 	     (ovp->v_mount->mnt_maxsymlinklen == 0 &&
    181 	      oip->i_din.ffs_din.di_blocks == 0))) {
    182 #ifdef DIAGNOSTIC
    183 		if (length != 0)
    184 			panic("ffs_truncate: partial truncate of symlink");
    185 #endif
    186 		memset((char *)&oip->i_ffs_shortlink, 0, (u_int)oip->i_ffs_size);
    187 		oip->i_ffs_size = 0;
    188 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    189 		return (VOP_UPDATE(ovp, &ts, &ts, 1));
    190 	}
    191 	if (oip->i_ffs_size == length) {
    192 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    193 		return (VOP_UPDATE(ovp, &ts, &ts, 0));
    194 	}
    195 #ifdef QUOTA
    196 	if ((error = getinoquota(oip)) != 0)
    197 		return (error);
    198 #endif
    199 	fs = oip->i_fs;
    200 	osize = oip->i_ffs_size;
    201 	ovp->v_lasta = ovp->v_clen = ovp->v_cstart = ovp->v_lastw = 0;
    202 	/*
    203 	 * Lengthen the size of the file. We must ensure that the
    204 	 * last byte of the file is allocated. Since the smallest
    205 	 * value of osize is 0, length will be at least 1.
    206 	 */
    207 	/*
    208 	 * XXXCHS why must the last byte of the file be allocated?
    209 	 * this seems bogus.
    210 	 */
    211 	if (osize < length) {
    212 		if (length > fs->fs_maxfilesize)
    213 			return (EFBIG);
    214 #ifdef UBC
    215 		aflags = 0;
    216 		bp = 0;
    217 #else
    218 		offset = blkoff(fs, length - 1);
    219 		lbn = lblkno(fs, length - 1);
    220 		aflags = B_CLRBUF;
    221 		if (ap->a_flags & IO_SYNC)
    222 			aflags |= B_SYNC;
    223 		error = ffs_balloc(oip, lbn, offset + 1, ap->a_cred, &bp, NULL,
    224 				   aflags);
    225 		if (error)
    226 			return (error);
    227 #endif
    228 		oip->i_ffs_size = length;
    229 #if defined(UVM)
    230 		uvm_vnp_setsize(ovp, length);
    231 		(void) uvm_vnp_uncache(ovp);
    232 #else
    233 		vnode_pager_setsize(ovp, length);
    234 		(void) vnode_pager_uncache(ovp);
    235 #endif
    236 #ifdef UBC
    237 #else
    238 		if (aflags & B_SYNC)
    239 			bwrite(bp);
    240 		else
    241 			bawrite(bp);
    242 #endif
    243 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
    244 		return (VOP_UPDATE(ovp, &ts, &ts, 1));
    245 	}
    246 	/*
    247 	 * Shorten the size of the file. If the file is not being
    248 	 * truncated to a block boundry, the contents of the
    249 	 * partial block following the end of the file must be
    250 	 * zero'ed in case it ever become accessable again because
    251 	 * of subsequent file growth.
    252 	 */
    253 	offset = blkoff(fs, length);
    254 	if (offset == 0) {
    255 		oip->i_ffs_size = length;
    256 	} else {
    257 		lbn = lblkno(fs, length);
    258 #ifdef UBC
    259 #else
    260 		aflags = B_CLRBUF;
    261 		if (ap->a_flags & IO_SYNC)
    262 			aflags |= B_SYNC;
    263 		error = ffs_balloc(oip, lbn, offset, ap->a_cred, &bp, NULL,
    264 				   aflags);
    265 		if (error)
    266 			return (error);
    267 #endif
    268 		oip->i_ffs_size = length;
    269 		size = blksize(fs, oip, lbn);
    270 #if defined(UVM)
    271 		(void) uvm_vnp_uncache(ovp);
    272 #else
    273 		(void) vnode_pager_uncache(ovp);
    274 #endif
    275 #ifdef UBC
    276 		uvm_vnp_zerorange(ovp, oip->i_ffs_size, size - offset);
    277 #else
    278 		memset((char *)bp->b_data + offset, 0,  (u_int)(size - offset));
    279 		allocbuf(bp, size);
    280 		if (aflags & B_SYNC)
    281 			bwrite(bp);
    282 		else
    283 			bawrite(bp);
    284 #endif
    285 	}
    286 #if defined(UVM)
    287 	uvm_vnp_setsize(ovp, length);
    288 #else
    289 	vnode_pager_setsize(ovp, length);
    290 #endif
    291 	/*
    292 	 * Calculate index into inode's block list of
    293 	 * last direct and indirect blocks (if any)
    294 	 * which we want to keep.  Lastblock is -1 when
    295 	 * the file is truncated to 0.
    296 	 */
    297 	lastblock = lblkno(fs, length + fs->fs_bsize - 1) - 1;
    298 	lastiblock[SINGLE] = lastblock - NDADDR;
    299 	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
    300 	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
    301 	nblocks = btodb(fs->fs_bsize);
    302 	/*
    303 	 * Update file and block pointers on disk before we start freeing
    304 	 * blocks.  If we crash before free'ing blocks below, the blocks
    305 	 * will be returned to the free list.  lastiblock values are also
    306 	 * normalized to -1 for calls to ffs_indirtrunc below.
    307 	 */
    308 	memcpy((caddr_t)oldblks, (caddr_t)&oip->i_ffs_db[0], sizeof oldblks);
    309 	for (level = TRIPLE; level >= SINGLE; level--)
    310 		if (lastiblock[level] < 0) {
    311 			oip->i_ffs_ib[level] = 0;
    312 			lastiblock[level] = -1;
    313 		}
    314 	for (i = NDADDR - 1; i > lastblock; i--)
    315 		oip->i_ffs_db[i] = 0;
    316 	oip->i_flag |= IN_CHANGE | IN_UPDATE;
    317 	if ((error = VOP_UPDATE(ovp, &ts, &ts, 1)) != 0)
    318 		allerror = error;
    319 	/*
    320 	 * Having written the new inode to disk, save its new configuration
    321 	 * and put back the old block pointers long enough to process them.
    322 	 * Note that we save the new block configuration so we can check it
    323 	 * when we are done.
    324 	 */
    325 	memcpy((caddr_t)newblks, (caddr_t)&oip->i_ffs_db[0], sizeof newblks);
    326 	memcpy((caddr_t)&oip->i_ffs_db[0], (caddr_t)oldblks, sizeof oldblks);
    327 	oip->i_ffs_size = osize;
    328 	vflags = ((length > 0) ? V_SAVE : 0) | V_SAVEMETA;
    329 	allerror = vinvalbuf(ovp, vflags, ap->a_cred, ap->a_p, 0, 0);
    330 
    331 	/*
    332 	 * Indirect blocks first.
    333 	 */
    334 	indir_lbn[SINGLE] = -NDADDR;
    335 	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
    336 	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
    337 	for (level = TRIPLE; level >= SINGLE; level--) {
    338 		bn = ufs_rw32(oip->i_ffs_ib[level], UFS_MPNEEDSWAP(ovp->v_mount));
    339 		if (bn != 0) {
    340 			error = ffs_indirtrunc(oip, indir_lbn[level],
    341 			    fsbtodb(fs, bn), lastiblock[level], level, &count);
    342 			if (error)
    343 				allerror = error;
    344 			blocksreleased += count;
    345 			if (lastiblock[level] < 0) {
    346 				oip->i_ffs_ib[level] = 0;
    347 				ffs_blkfree(oip, bn, fs->fs_bsize);
    348 				blocksreleased += nblocks;
    349 			}
    350 		}
    351 		if (lastiblock[level] >= 0)
    352 			goto done;
    353 	}
    354 
    355 	/*
    356 	 * All whole direct blocks or frags.
    357 	 */
    358 	for (i = NDADDR - 1; i > lastblock; i--) {
    359 		register long bsize;
    360 
    361 		bn = ufs_rw32(oip->i_ffs_db[i], UFS_MPNEEDSWAP(ovp->v_mount));
    362 		if (bn == 0)
    363 			continue;
    364 		oip->i_ffs_db[i] = 0;
    365 		bsize = blksize(fs, oip, i);
    366 		ffs_blkfree(oip, bn, bsize);
    367 		blocksreleased += btodb(bsize);
    368 	}
    369 	if (lastblock < 0)
    370 		goto done;
    371 
    372 	/*
    373 	 * Finally, look for a change in size of the
    374 	 * last direct block; release any frags.
    375 	 */
    376 	bn = ufs_rw32(oip->i_ffs_db[lastblock], UFS_MPNEEDSWAP(ovp->v_mount));
    377 	if (bn != 0) {
    378 		long oldspace, newspace;
    379 
    380 		/*
    381 		 * Calculate amount of space we're giving
    382 		 * back as old block size minus new block size.
    383 		 */
    384 		oldspace = blksize(fs, oip, lastblock);
    385 		oip->i_ffs_size = length;
    386 		newspace = blksize(fs, oip, lastblock);
    387 		if (newspace == 0)
    388 			panic("itrunc: newspace");
    389 		if (oldspace - newspace > 0) {
    390 			/*
    391 			 * Block number of space to be free'd is
    392 			 * the old block # plus the number of frags
    393 			 * required for the storage we're keeping.
    394 			 */
    395 			bn += numfrags(fs, newspace);
    396 			ffs_blkfree(oip, bn, oldspace - newspace);
    397 			blocksreleased += btodb(oldspace - newspace);
    398 		}
    399 	}
    400 done:
    401 #ifdef DIAGNOSTIC
    402 	for (level = SINGLE; level <= TRIPLE; level++)
    403 		if (newblks[NDADDR + level] != oip->i_ffs_ib[level])
    404 			panic("itrunc1");
    405 	for (i = 0; i < NDADDR; i++)
    406 		if (newblks[i] != oip->i_ffs_db[i])
    407 			panic("itrunc2");
    408 	if (length == 0 &&
    409 	    (ovp->v_dirtyblkhd.lh_first || ovp->v_cleanblkhd.lh_first))
    410 		panic("itrunc3");
    411 #endif /* DIAGNOSTIC */
    412 	/*
    413 	 * Put back the real size.
    414 	 */
    415 	oip->i_ffs_size = length;
    416 	oip->i_ffs_blocks -= blocksreleased;
    417 	if (oip->i_ffs_blocks < 0)			/* sanity */
    418 		oip->i_ffs_blocks = 0;
    419 	oip->i_flag |= IN_CHANGE;
    420 #ifdef QUOTA
    421 	(void) chkdq(oip, -blocksreleased, NOCRED, 0);
    422 #endif
    423 	return (allerror);
    424 }
    425 
    426 /*
    427  * Release blocks associated with the inode ip and stored in the indirect
    428  * block bn.  Blocks are free'd in LIFO order up to (but not including)
    429  * lastbn.  If level is greater than SINGLE, the block is an indirect block
    430  * and recursive calls to indirtrunc must be used to cleanse other indirect
    431  * blocks.
    432  *
    433  * NB: triple indirect blocks are untested.
    434  */
    435 static int
    436 ffs_indirtrunc(ip, lbn, dbn, lastbn, level, countp)
    437 	register struct inode *ip;
    438 	ufs_daddr_t lbn, lastbn;
    439 	ufs_daddr_t dbn;
    440 	int level;
    441 	long *countp;
    442 {
    443 	register int i;
    444 	struct buf *bp;
    445 	register struct fs *fs = ip->i_fs;
    446 	register ufs_daddr_t *bap;
    447 	struct vnode *vp;
    448 	ufs_daddr_t *copy = NULL, nb, nlbn, last;
    449 	long blkcount, factor;
    450 	int nblocks, blocksreleased = 0;
    451 	int error = 0, allerror = 0;
    452 
    453 	/*
    454 	 * Calculate index in current block of last
    455 	 * block to be kept.  -1 indicates the entire
    456 	 * block so we need not calculate the index.
    457 	 */
    458 	factor = 1;
    459 	for (i = SINGLE; i < level; i++)
    460 		factor *= NINDIR(fs);
    461 	last = lastbn;
    462 	if (lastbn > 0)
    463 		last /= factor;
    464 	nblocks = btodb(fs->fs_bsize);
    465 	/*
    466 	 * Get buffer of block pointers, zero those entries corresponding
    467 	 * to blocks to be free'd, and update on disk copy first.  Since
    468 	 * double(triple) indirect before single(double) indirect, calls
    469 	 * to bmap on these blocks will fail.  However, we already have
    470 	 * the on disk address, so we have to set the b_blkno field
    471 	 * explicitly instead of letting bread do everything for us.
    472 	 */
    473 	vp = ITOV(ip);
    474 	bp = getblk(vp, lbn, (int)fs->fs_bsize, 0, 0);
    475 	if (bp->b_flags & (B_DONE | B_DELWRI)) {
    476 		/* Braces must be here in case trace evaluates to nothing. */
    477 		trace(TR_BREADHIT, pack(vp, fs->fs_bsize), lbn);
    478 	} else {
    479 		trace(TR_BREADMISS, pack(vp, fs->fs_bsize), lbn);
    480 		curproc->p_stats->p_ru.ru_inblock++;	/* pay for read */
    481 		bp->b_flags |= B_READ;
    482 		if (bp->b_bcount > bp->b_bufsize)
    483 			panic("ffs_indirtrunc: bad buffer size");
    484 		bp->b_blkno = dbn;
    485 		VOP_STRATEGY(bp);
    486 		error = biowait(bp);
    487 	}
    488 	if (error) {
    489 		brelse(bp);
    490 		*countp = 0;
    491 		return (error);
    492 	}
    493 
    494 	bap = (ufs_daddr_t *)bp->b_data;
    495 	if (lastbn != -1) {
    496 		MALLOC(copy, ufs_daddr_t *, fs->fs_bsize, M_TEMP, M_WAITOK);
    497 		memcpy((caddr_t)copy, (caddr_t)bap, (u_int)fs->fs_bsize);
    498 		memset((caddr_t)&bap[last + 1], 0,
    499 		  (u_int)(NINDIR(fs) - (last + 1)) * sizeof (ufs_daddr_t));
    500 		error = bwrite(bp);
    501 		if (error)
    502 			allerror = error;
    503 		bap = copy;
    504 	}
    505 
    506 	/*
    507 	 * Recursively free totally unused blocks.
    508 	 */
    509 	for (i = NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
    510 	    i--, nlbn += factor) {
    511 		nb = ufs_rw32(bap[i], UFS_MPNEEDSWAP(vp->v_mount));
    512 		if (nb == 0)
    513 			continue;
    514 		if (level > SINGLE) {
    515 			error = ffs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
    516 					       (ufs_daddr_t)-1, level - 1,
    517 					       &blkcount);
    518 			if (error)
    519 				allerror = error;
    520 			blocksreleased += blkcount;
    521 		}
    522 		ffs_blkfree(ip, nb, fs->fs_bsize);
    523 		blocksreleased += nblocks;
    524 	}
    525 
    526 	/*
    527 	 * Recursively free last partial block.
    528 	 */
    529 	if (level > SINGLE && lastbn >= 0) {
    530 		last = lastbn % factor;
    531 		nb = ufs_rw32(bap[i], UFS_MPNEEDSWAP(vp->v_mount));
    532 		if (nb != 0) {
    533 			error = ffs_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
    534 					       last, level - 1, &blkcount);
    535 			if (error)
    536 				allerror = error;
    537 			blocksreleased += blkcount;
    538 		}
    539 	}
    540 
    541 	if (copy != NULL) {
    542 		FREE(copy, M_TEMP);
    543 	} else {
    544 		bp->b_flags |= B_INVAL;
    545 		brelse(bp);
    546 	}
    547 
    548 	*countp = blocksreleased;
    549 	return (allerror);
    550 }
    551