xref: /netbsd/sys/ufs/lfs/lfs_inode.c (revision bf9ec67e)
1 /*	$NetBSD: lfs_inode.c,v 1.57 2002/05/14 20:03:54 perseant Exp $	*/
2 
3 /*-
4  * Copyright (c) 1999, 2000 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Konrad E. Schroder <perseant@hhhh.org>.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  * 3. All advertising materials mentioning features or use of this software
19  *    must display the following acknowledgement:
20  *      This product includes software developed by the NetBSD
21  *      Foundation, Inc. and its contributors.
22  * 4. Neither the name of The NetBSD Foundation nor the names of its
23  *    contributors may be used to endorse or promote products derived
24  *    from this software without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36  * POSSIBILITY OF SUCH DAMAGE.
37  */
38 /*
39  * Copyright (c) 1986, 1989, 1991, 1993
40  *	The Regents of the University of California.  All rights reserved.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  * 3. All advertising materials mentioning features or use of this software
51  *    must display the following acknowledgement:
52  *	This product includes software developed by the University of
53  *	California, Berkeley and its contributors.
54  * 4. Neither the name of the University nor the names of its contributors
55  *    may be used to endorse or promote products derived from this software
56  *    without specific prior written permission.
57  *
58  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
59  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
60  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
61  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
62  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
63  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
64  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
65  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
66  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
67  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
68  * SUCH DAMAGE.
69  *
70  *	@(#)lfs_inode.c	8.9 (Berkeley) 5/8/95
71  */
72 
73 #include <sys/cdefs.h>
74 __KERNEL_RCSID(0, "$NetBSD: lfs_inode.c,v 1.57 2002/05/14 20:03:54 perseant Exp $");
75 
76 #if defined(_KERNEL_OPT)
77 #include "opt_quota.h"
78 #endif
79 
80 #include <sys/param.h>
81 #include <sys/systm.h>
82 #include <sys/mount.h>
83 #include <sys/proc.h>
84 #include <sys/file.h>
85 #include <sys/buf.h>
86 #include <sys/vnode.h>
87 #include <sys/kernel.h>
88 #include <sys/malloc.h>
89 #include <sys/trace.h>
90 #include <sys/resourcevar.h>
91 
92 #include <ufs/ufs/quota.h>
93 #include <ufs/ufs/inode.h>
94 #include <ufs/ufs/ufsmount.h>
95 #include <ufs/ufs/ufs_extern.h>
96 
97 #include <ufs/lfs/lfs.h>
98 #include <ufs/lfs/lfs_extern.h>
99 
100 extern int locked_queue_count;
101 extern long locked_queue_bytes;
102 
103 static int lfs_update_seguse(struct lfs *, long, size_t);
104 static int lfs_indirtrunc (struct inode *, ufs_daddr_t, ufs_daddr_t,
105 			   ufs_daddr_t, int, long *, long *, long *, size_t *,
106 			   struct proc *);
107 static int lfs_blkfree (struct lfs *, daddr_t, size_t, long *, size_t *);
108 static int lfs_vtruncbuf(struct vnode *, daddr_t, int, int);
109 
110 /* Search a block for a specific dinode. */
111 struct dinode *
112 lfs_ifind(struct lfs *fs, ino_t ino, struct buf *bp)
113 {
114 	struct dinode *dip = (struct dinode *)bp->b_data;
115 	struct dinode *ldip, *fin;
116 
117 #ifdef LFS_IFILE_FRAG_ADDRESSING
118 	if (fs->lfs_version == 1)
119 		fin = dip + INOPB(fs);
120 	else
121 		fin = dip + INOPF(fs);
122 #else
123 	fin = dip + INOPB(fs);
124 #endif
125 
126 	/*
127 	 * XXX we used to go from the top down here, presumably with the
128 	 * idea that the same inode could be written twice in the same
129 	 * block (which is not supposed to be true).
130 	 */
131 	for (ldip = dip; ldip < fin; ++ldip)
132 		if (ldip->di_inumber == ino)
133 			return (ldip);
134 
135 	printf("searched %d entries\n", (int)(fin - dip));
136 	printf("offset is 0x%x (seg %d)\n", fs->lfs_offset,
137 	       dtosn(fs, fs->lfs_offset));
138 	printf("block is 0x%x (seg %d)\n", dbtofsb(fs, bp->b_blkno),
139 	       dtosn(fs, dbtofsb(fs, bp->b_blkno)));
140 
141 	return NULL;
142 }
143 
144 int
145 lfs_update(void *v)
146 {
147 	struct vop_update_args /* {
148 				  struct vnode *a_vp;
149 				  struct timespec *a_access;
150 				  struct timespec *a_modify;
151 				  int a_flags;
152 				  } */ *ap = v;
153 	struct inode *ip;
154 	struct vnode *vp = ap->a_vp;
155 	struct timespec ts;
156 	struct lfs *fs = VFSTOUFS(vp->v_mount)->um_lfs;
157 	int s;
158 
159 	if (vp->v_mount->mnt_flag & MNT_RDONLY)
160 		return (0);
161 	ip = VTOI(vp);
162 
163 	/*
164 	 * If we are called from vinvalbuf, and the file's blocks have
165 	 * already been scheduled for writing, but the writes have not
166 	 * yet completed, lfs_vflush will not be called, and vinvalbuf
167 	 * will cause a panic.  So, we must wait until any pending write
168 	 * for our inode completes, if we are called with UPDATE_WAIT set.
169 	 */
170 	s = splbio();
171 	while ((ap->a_flags & (UPDATE_WAIT|UPDATE_DIROP)) == UPDATE_WAIT &&
172 	    WRITEINPROG(vp)) {
173 #ifdef DEBUG_LFS
174 		printf("lfs_update: sleeping on inode %d (in-progress)\n",
175 		       ip->i_number);
176 #endif
177 		tsleep(vp, (PRIBIO+1), "lfs_update", 0);
178 	}
179 	splx(s);
180 	TIMEVAL_TO_TIMESPEC(&time, &ts);
181 	LFS_ITIMES(ip,
182 		   ap->a_access ? ap->a_access : &ts,
183 		   ap->a_modify ? ap->a_modify : &ts, &ts);
184 	if ((ip->i_flag & (IN_MODIFIED | IN_ACCESSED | IN_CLEANING)) == 0) {
185 		return (0);
186 	}
187 
188 	/* If sync, push back the vnode and any dirty blocks it may have. */
189 	if ((ap->a_flags & (UPDATE_WAIT|UPDATE_DIROP)) == UPDATE_WAIT) {
190 		/* Avoid flushing VDIROP. */
191 		++fs->lfs_diropwait;
192 		while (vp->v_flag & VDIROP) {
193 #ifdef DEBUG_LFS
194 			printf("lfs_update: sleeping on inode %d (dirops)\n",
195 			       ip->i_number);
196 			printf("lfs_update: vflags 0x%lx, iflags 0x%x\n",
197 				vp->v_flag, ip->i_flag);
198 #endif
199 			if (fs->lfs_dirops == 0)
200 				lfs_flush_fs(fs, SEGM_SYNC);
201 			else
202 				tsleep(&fs->lfs_writer, PRIBIO+1, "lfs_fsync",
203 				       0);
204 			/* XXX KS - by falling out here, are we writing the vn
205 			twice? */
206 		}
207 		--fs->lfs_diropwait;
208 		return lfs_vflush(vp);
209         }
210 	return 0;
211 }
212 
213 #define	SINGLE	0	/* index of single indirect block */
214 #define	DOUBLE	1	/* index of double indirect block */
215 #define	TRIPLE	2	/* index of triple indirect block */
216 /*
217  * Truncate the inode oip to at most length size, freeing the
218  * disk blocks.
219  */
220 /* VOP_BWRITE 1 + NIADDR + VOP_BALLOC == 2 + 2*NIADDR times */
221 int
222 lfs_truncate(void *v)
223 {
224 	struct vop_truncate_args /* {
225 		struct vnode *a_vp;
226 		off_t a_length;
227 		int a_flags;
228 		struct ucred *a_cred;
229 		struct proc *a_p;
230 	} */ *ap = v;
231 	struct vnode *ovp = ap->a_vp;
232 	ufs_daddr_t lastblock;
233 	struct inode *oip;
234 	ufs_daddr_t bn, lbn, lastiblock[NIADDR], indir_lbn[NIADDR];
235 	ufs_daddr_t newblks[NDADDR + NIADDR];
236 	off_t length = ap->a_length;
237 	struct lfs *fs;
238 	struct buf *bp;
239 	int offset, size, level;
240 	long count, rcount, nblocks, blocksreleased = 0, real_released = 0;
241 	int i;
242 	int aflags, error, allerror = 0;
243 	off_t osize;
244 	long lastseg;
245 	size_t bc;
246 	int obufsize, odb;
247 
248 	if (length < 0)
249 		return (EINVAL);
250 	oip = VTOI(ovp);
251 
252 	/*
253 	 * Just return and not update modification times.
254 	 */
255 	if (oip->i_ffs_size == length)
256 		return (0);
257 
258 	if (ovp->v_type == VLNK &&
259 	    (oip->i_ffs_size < ovp->v_mount->mnt_maxsymlinklen ||
260 	     (ovp->v_mount->mnt_maxsymlinklen == 0 &&
261 	      oip->i_din.ffs_din.di_blocks == 0))) {
262 #ifdef DIAGNOSTIC
263 		if (length != 0)
264 			panic("lfs_truncate: partial truncate of symlink");
265 #endif
266 		memset((char *)&oip->i_ffs_shortlink, 0, (u_int)oip->i_ffs_size);
267 		oip->i_ffs_size = 0;
268 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
269 		return (VOP_UPDATE(ovp, NULL, NULL, 0));
270 	}
271 	if (oip->i_ffs_size == length) {
272 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
273 		return (VOP_UPDATE(ovp, NULL, NULL, 0));
274 	}
275 #ifdef QUOTA
276 	if ((error = getinoquota(oip)) != 0)
277 		return (error);
278 #endif
279 	fs = oip->i_lfs;
280 	lfs_imtime(fs);
281 	osize = oip->i_ffs_size;
282 
283 	/*
284 	 * Lengthen the size of the file. We must ensure that the
285 	 * last byte of the file is allocated. Since the smallest
286 	 * value of osize is 0, length will be at least 1.
287 	 */
288 	if (osize < length) {
289 		if (length > fs->lfs_maxfilesize)
290 			return (EFBIG);
291 		aflags = B_CLRBUF;
292 		if (ap->a_flags & IO_SYNC)
293 			aflags |= B_SYNC;
294 		error = lfs_reserve(fs, ovp, btofsb(fs, (NIADDR + 2) << fs->lfs_bshift));
295 		if (error)
296 			return (error);
297 		error = VOP_BALLOC(ovp, length - 1, 1, ap->a_cred, aflags, &bp);
298 		lfs_reserve(fs, ovp, -btofsb(fs, (NIADDR + 2) << fs->lfs_bshift));
299 		if (error)
300 			return (error);
301 		oip->i_ffs_size = length;
302 		uvm_vnp_setsize(ovp, length);
303 		(void) VOP_BWRITE(bp);
304 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
305 		return (VOP_UPDATE(ovp, NULL, NULL, 0));
306 	}
307 
308 	if ((error = lfs_reserve(fs, ovp, btofsb(fs, (2 * NIADDR + 3) << fs->lfs_bshift))) != 0)
309 		return (error);
310 	/*
311 	 * Make sure no writes to this inode can happen while we're
312 	 * truncating.  Otherwise, blocks which are accounted for on the
313 	 * inode *and* which have been created for cleaning can coexist,
314 	 * and cause an overcounting.
315 	 *
316 	 * (We don't need to *hold* the seglock, though, because we already
317 	 * hold the inode lock; draining the seglock is sufficient.)
318 	 */
319 #ifdef LFS_AGGRESSIVE_SEGLOCK
320 	lfs_seglock(fs, SEGM_PROT);
321 #else
322 	if (ovp != fs->lfs_unlockvp) {
323 		while (fs->lfs_seglock) {
324 			tsleep(&fs->lfs_seglock, PRIBIO+1, "lfs_truncate", 0);
325 		}
326 	}
327 #endif
328 
329 	/*
330 	 * Shorten the size of the file. If the file is not being
331 	 * truncated to a block boundary, the contents of the
332 	 * partial block following the end of the file must be
333 	 * zero'ed in case it ever becomes accessible again because
334 	 * of subsequent file growth. Directories however are not
335 	 * zero'ed as they should grow back initialized to empty.
336 	 */
337 	offset = blkoff(fs, length);
338 	lastseg = -1;
339 	bc = 0;
340 	if (offset == 0) {
341 		oip->i_ffs_size = length;
342 	} else {
343 		lbn = lblkno(fs, length);
344 		aflags = B_CLRBUF;
345 		if (ap->a_flags & IO_SYNC)
346 			aflags |= B_SYNC;
347 		error = VOP_BALLOC(ovp, length - 1, 1, ap->a_cred, aflags, &bp);
348 		if (error) {
349 			lfs_reserve(fs, ovp, -btofsb(fs, (2 * NIADDR + 3) << fs->lfs_bshift));
350 #ifdef LFS_AGGRESSIVE_SEGLOCK
351 			lfs_segunlock(fs);
352 #endif
353 			return (error);
354 		}
355 		obufsize = bp->b_bufsize;
356 		odb = btofsb(fs, bp->b_bcount);
357 		oip->i_ffs_size = length;
358 		size = blksize(fs, oip, lbn);
359 		if (ovp->v_type != VDIR)
360 			memset((char *)bp->b_data + offset, 0,
361 			       (u_int)(size - offset));
362 		allocbuf(bp, size);
363 		if ((bp->b_flags & (B_LOCKED | B_CALL)) == B_LOCKED)
364 			locked_queue_bytes -= obufsize - bp->b_bufsize;
365 		if (bp->b_flags & B_DELWRI)
366 			fs->lfs_avail += odb - btofsb(fs, size);
367 		(void) VOP_BWRITE(bp);
368 	}
369 	uvm_vnp_setsize(ovp, length);
370 	/*
371 	 * Calculate index into inode's block list of
372 	 * last direct and indirect blocks (if any)
373 	 * which we want to keep.  Lastblock is -1 when
374 	 * the file is truncated to 0.
375 	 */
376 	lastblock = lblkno(fs, length + fs->lfs_bsize - 1) - 1;
377 	lastiblock[SINGLE] = lastblock - NDADDR;
378 	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
379 	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
380 	nblocks = btofsb(fs, fs->lfs_bsize);
381 	/*
382 	 * Record changed file and block pointers before we start
383 	 * freeing blocks.  lastiblock values are also normalized to -1
384 	 * for calls to lfs_indirtrunc below.
385 	 */
386 	memcpy((caddr_t)newblks, (caddr_t)&oip->i_ffs_db[0], sizeof newblks);
387 	for (level = TRIPLE; level >= SINGLE; level--)
388 		if (lastiblock[level] < 0) {
389 			newblks[NDADDR+level] = 0;
390 			lastiblock[level] = -1;
391 		}
392 	for (i = NDADDR - 1; i > lastblock; i--)
393 		newblks[i] = 0;
394 
395 	oip->i_ffs_size = osize;
396 	error = lfs_vtruncbuf(ovp, lastblock + 1, 0, 0);
397 	if (error && !allerror)
398 		allerror = error;
399 
400 	/*
401 	 * Indirect blocks first.
402 	 */
403 	indir_lbn[SINGLE] = -NDADDR;
404 	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
405 	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
406 	for (level = TRIPLE; level >= SINGLE; level--) {
407 		bn = oip->i_ffs_ib[level];
408 		if (bn != 0) {
409 			error = lfs_indirtrunc(oip, indir_lbn[level],
410 					       bn, lastiblock[level],
411 					       level, &count, &rcount,
412 					       &lastseg, &bc, ap->a_p);
413 			if (error)
414 				allerror = error;
415 			real_released += rcount;
416 			blocksreleased += count;
417 			if (lastiblock[level] < 0) {
418 				if (oip->i_ffs_ib[level] > 0)
419 					real_released += nblocks;
420 				blocksreleased += nblocks;
421 				oip->i_ffs_ib[level] = 0;
422 				lfs_blkfree(fs, bn, fs->lfs_bsize, &lastseg, &bc);
423 			}
424 		}
425 		if (lastiblock[level] >= 0)
426 			goto done;
427 	}
428 
429 	/*
430 	 * All whole direct blocks or frags.
431 	 */
432 	for (i = NDADDR - 1; i > lastblock; i--) {
433 		long bsize;
434 
435 		bn = oip->i_ffs_db[i];
436 		if (bn == 0)
437 			continue;
438 		bsize = blksize(fs, oip, i);
439 		if (oip->i_ffs_db[i] > 0)
440 			real_released += btofsb(fs, bsize);
441 		blocksreleased += btofsb(fs, bsize);
442 		oip->i_ffs_db[i] = 0;
443 		lfs_blkfree(fs, bn, bsize, &lastseg, &bc);
444 	}
445 	if (lastblock < 0)
446 		goto done;
447 
448 	/*
449 	 * Finally, look for a change in size of the
450 	 * last direct block; release any frags.
451 	 */
452 	bn = oip->i_ffs_db[lastblock];
453 	if (bn != 0) {
454 		long oldspace, newspace;
455 
456 		/*
457 		 * Calculate amount of space we're giving
458 		 * back as old block size minus new block size.
459 		 */
460 		oldspace = blksize(fs, oip, lastblock);
461 		oip->i_ffs_size = length;
462 		newspace = blksize(fs, oip, lastblock);
463 		if (newspace == 0)
464 			panic("itrunc: newspace");
465 		if (oldspace - newspace > 0) {
466 			lfs_blkfree(fs, bn, oldspace - newspace, &lastseg, &bc);
467 			if (bn > 0)
468 				real_released += btofsb(fs, oldspace - newspace);
469 			blocksreleased += btofsb(fs, oldspace - newspace);
470 		}
471 	}
472 
473 done:
474 	/* Finish segment accounting corrections */
475 	lfs_update_seguse(fs, lastseg, bc);
476 #ifdef DIAGNOSTIC
477 	for (level = SINGLE; level <= TRIPLE; level++)
478 		if (newblks[NDADDR + level] != oip->i_ffs_ib[level])
479 			panic("lfs itrunc1");
480 	for (i = 0; i < NDADDR; i++)
481 		if (newblks[i] != oip->i_ffs_db[i])
482 			panic("lfs itrunc2");
483 	if (length == 0 &&
484 	    (!LIST_EMPTY(&ovp->v_cleanblkhd) || !LIST_EMPTY(&ovp->v_dirtyblkhd)))
485 		panic("lfs itrunc3");
486 #endif /* DIAGNOSTIC */
487 	/*
488 	 * Put back the real size.
489 	 */
490 	oip->i_ffs_size = length;
491 	oip->i_lfs_effnblks -= blocksreleased;
492 	oip->i_ffs_blocks -= real_released;
493 	fs->lfs_bfree += blocksreleased;
494 #ifdef DIAGNOSTIC
495 	if (oip->i_ffs_size == 0 && oip->i_ffs_blocks != 0) {
496 		printf("lfs_truncate: truncate to 0 but %d blocks on inode\n",
497 		       oip->i_ffs_blocks);
498 		panic("lfs_truncate: persistent blocks\n");
499 	}
500 #endif
501 	oip->i_flag |= IN_CHANGE;
502 #ifdef QUOTA
503 	(void) chkdq(oip, -blocksreleased, NOCRED, 0);
504 #endif
505 	lfs_reserve(fs, ovp, -btofsb(fs, (2 * NIADDR + 3) << fs->lfs_bshift));
506 #ifdef LFS_AGGRESSIVE_SEGLOCK
507 	lfs_segunlock(fs);
508 #endif
509 	return (allerror);
510 }
511 
512 /* Update segment usage information when removing a block. */
513 static int
514 lfs_blkfree(struct lfs *fs, daddr_t daddr, size_t bsize, long *lastseg,
515 	    size_t *num)
516 {
517 	long seg;
518 	int error = 0;
519 
520 	bsize = fragroundup(fs, bsize);
521 	if (daddr > 0) {
522 		if (*lastseg != (seg = dtosn(fs, daddr))) {
523 			error = lfs_update_seguse(fs, *lastseg, *num);
524 			*num = bsize;
525 			*lastseg = seg;
526 		} else
527 			*num += bsize;
528 	}
529 	return error;
530 }
531 
532 /* Finish the accounting updates for a segment. */
533 static int
534 lfs_update_seguse(struct lfs *fs, long lastseg, size_t num)
535 {
536 	SEGUSE *sup;
537 	struct buf *bp;
538 	int error;
539 
540 	if (lastseg < 0 || num == 0)
541 		return 0;
542 
543 	LFS_SEGENTRY(sup, fs, lastseg, bp);
544 	if (num > sup->su_nbytes) {
545 		printf("lfs_truncate: segment %ld short by %ld\n",
546 		       lastseg, (long)num - sup->su_nbytes);
547 		panic("lfs_truncate: negative bytes");
548 		sup->su_nbytes = num;
549 	}
550 	sup->su_nbytes -= num;
551 	error = LFS_BWRITE_LOG(bp); /* Ifile */
552 	return error;
553 }
554 
555 /*
556  * Release blocks associated with the inode ip and stored in the indirect
557  * block bn.  Blocks are free'd in LIFO order up to (but not including)
558  * lastbn.  If level is greater than SINGLE, the block is an indirect block
559  * and recursive calls to indirtrunc must be used to cleanse other indirect
560  * blocks.
561  *
562  * NB: triple indirect blocks are untested.
563  */
564 static int
565 lfs_indirtrunc(struct inode *ip, ufs_daddr_t lbn, daddr_t dbn,
566 	       ufs_daddr_t lastbn, int level, long *countp,
567 	       long *rcountp, long *lastsegp, size_t *bcp, struct proc *p)
568 {
569 	int i;
570 	struct buf *bp;
571 	struct lfs *fs = ip->i_lfs;
572 	ufs_daddr_t *bap;
573 	struct vnode *vp;
574 	ufs_daddr_t *copy = NULL, nb, nlbn, last;
575 	long blkcount, rblkcount, factor;
576 	int nblocks, blocksreleased = 0, real_released = 0;
577 	int error = 0, allerror = 0;
578 
579 	/*
580 	 * Calculate index in current block of last
581 	 * block to be kept.  -1 indicates the entire
582 	 * block so we need not calculate the index.
583 	 */
584 	factor = 1;
585 	for (i = SINGLE; i < level; i++)
586 		factor *= NINDIR(fs);
587 	last = lastbn;
588 	if (lastbn > 0)
589 		last /= factor;
590 	nblocks = btofsb(fs, fs->lfs_bsize);
591 	/*
592 	 * Get buffer of block pointers, zero those entries corresponding
593 	 * to blocks to be free'd, and update on disk copy first.  Since
594 	 * double(triple) indirect before single(double) indirect, calls
595 	 * to bmap on these blocks will fail.  However, we already have
596 	 * the on disk address, so we have to set the b_blkno field
597 	 * explicitly instead of letting bread do everything for us.
598 	 */
599 	vp = ITOV(ip);
600 	bp = getblk(vp, lbn, (int)fs->lfs_bsize, 0, 0);
601 	if (bp->b_flags & (B_DONE | B_DELWRI)) {
602 		/* Braces must be here in case trace evaluates to nothing. */
603 		trace(TR_BREADHIT, pack(vp, fs->lfs_bsize), lbn);
604 	} else {
605 		trace(TR_BREADMISS, pack(vp, fs->lfs_bsize), lbn);
606 		p->p_stats->p_ru.ru_inblock++;	/* pay for read */
607 		bp->b_flags |= B_READ;
608 		if (bp->b_bcount > bp->b_bufsize)
609 			panic("lfs_indirtrunc: bad buffer size");
610 		bp->b_blkno = fsbtodb(fs, dbn);
611 		VOP_STRATEGY(bp);
612 		error = biowait(bp);
613 	}
614 	if (error) {
615 		brelse(bp);
616 		*countp = *rcountp = 0;
617 		return (error);
618 	}
619 
620 	bap = (ufs_daddr_t *)bp->b_data;
621 	if (lastbn >= 0) {
622 		MALLOC(copy, ufs_daddr_t *, fs->lfs_bsize, M_TEMP, M_WAITOK);
623 		memcpy((caddr_t)copy, (caddr_t)bap, (u_int)fs->lfs_bsize);
624 		memset((caddr_t)&bap[last + 1], 0,
625 		  (u_int)(NINDIR(fs) - (last + 1)) * sizeof (ufs_daddr_t));
626 		error = VOP_BWRITE(bp);
627 		if (error)
628 			allerror = error;
629 		bap = copy;
630 	}
631 
632 	/*
633 	 * Recursively free totally unused blocks.
634 	 */
635 	for (i = NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
636 	    i--, nlbn += factor) {
637 		nb = bap[i];
638 		if (nb == 0)
639 			continue;
640 		if (level > SINGLE) {
641 			error = lfs_indirtrunc(ip, nlbn, nb,
642 					       (ufs_daddr_t)-1, level - 1,
643 					       &blkcount, &rblkcount,
644 					       lastsegp, bcp, p);
645 			if (error)
646 				allerror = error;
647 			blocksreleased += blkcount;
648 			real_released += rblkcount;
649 		}
650 		lfs_blkfree(fs, nb, fs->lfs_bsize, lastsegp, bcp);
651 		if (bap[i] > 0)
652 			real_released += nblocks;
653 		blocksreleased += nblocks;
654 	}
655 
656 	/*
657 	 * Recursively free last partial block.
658 	 */
659 	if (level > SINGLE && lastbn >= 0) {
660 		last = lastbn % factor;
661 		nb = bap[i];
662 		if (nb != 0) {
663 			error = lfs_indirtrunc(ip, nlbn, nb,
664 					       last, level - 1, &blkcount,
665 					       &rblkcount, lastsegp, bcp, p);
666 			if (error)
667 				allerror = error;
668 			real_released += rblkcount;
669 			blocksreleased += blkcount;
670 		}
671 	}
672 
673 	if (copy != NULL) {
674 		FREE(copy, M_TEMP);
675 	} else {
676 		if (bp->b_flags & B_DELWRI) {
677 			LFS_UNLOCK_BUF(bp);
678 			fs->lfs_avail += btofsb(fs, bp->b_bcount);
679 			wakeup(&fs->lfs_avail);
680 		}
681 		bp->b_flags |= B_INVAL;
682 		brelse(bp);
683 	}
684 
685 	*countp = blocksreleased;
686 	*rcountp = real_released;
687 	return (allerror);
688 }
689 
690 /*
691  * Destroy any in core blocks past the truncation length.
692  * Inlined from vtruncbuf, so that lfs_avail could be updated.
693  */
694 static int
695 lfs_vtruncbuf(struct vnode *vp, daddr_t lbn, int slpflag, int slptimeo)
696 {
697 	struct buf *bp, *nbp;
698 	int s, error;
699 	struct lfs *fs;
700 
701 	fs = VTOI(vp)->i_lfs;
702 	s = splbio();
703 
704 restart:
705 	for (bp = LIST_FIRST(&vp->v_cleanblkhd); bp; bp = nbp) {
706 		nbp = LIST_NEXT(bp, b_vnbufs);
707 		if (bp->b_lblkno < lbn)
708 			continue;
709 		if (bp->b_flags & B_BUSY) {
710 			bp->b_flags |= B_WANTED;
711 			error = tsleep((caddr_t)bp, slpflag | (PRIBIO + 1),
712 			    "lfs_vtruncbuf", slptimeo);
713 			if (error) {
714 				splx(s);
715 				return (error);
716 			}
717 			goto restart;
718 		}
719 		bp->b_flags |= B_BUSY | B_INVAL | B_VFLUSH;
720 		if (bp->b_flags & B_DELWRI) {
721 			bp->b_flags &= ~B_DELWRI;
722 			fs->lfs_avail += btofsb(fs, bp->b_bcount);
723 			wakeup(&fs->lfs_avail);
724 		}
725 		LFS_UNLOCK_BUF(bp);
726 		brelse(bp);
727 	}
728 
729 	for (bp = LIST_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) {
730 		nbp = LIST_NEXT(bp, b_vnbufs);
731 		if (bp->b_lblkno < lbn)
732 			continue;
733 		if (bp->b_flags & B_BUSY) {
734 			bp->b_flags |= B_WANTED;
735 			error = tsleep((caddr_t)bp, slpflag | (PRIBIO + 1),
736 			    "lfs_vtruncbuf", slptimeo);
737 			if (error) {
738 				splx(s);
739 				return (error);
740 			}
741 			goto restart;
742 		}
743 		bp->b_flags |= B_BUSY | B_INVAL | B_VFLUSH;
744 		if (bp->b_flags & B_DELWRI) {
745 			bp->b_flags &= ~B_DELWRI;
746 			fs->lfs_avail += btofsb(fs, bp->b_bcount);
747 			wakeup(&fs->lfs_avail);
748 		}
749 		LFS_UNLOCK_BUF(bp);
750 		brelse(bp);
751 	}
752 
753 	splx(s);
754 
755 	return (0);
756 }
757 
758