xref: /dragonfly/sys/vfs/ext2fs/ext2_inode.c (revision e6d22e9b)
1 /*-
2  *  modified for Lites 1.1
3  *
4  *  Aug 1995, Godmar Back (gback@cs.utah.edu)
5  *  University of Utah, Department of Computer Science
6  */
7 /*-
8  * SPDX-License-Identifier: BSD-3-Clause
9  *
10  * Copyright (c) 1982, 1986, 1989, 1993
11  *	The Regents of the University of California.  All rights reserved.
12  *
13  * Redistribution and use in source and binary forms, with or without
14  * modification, are permitted provided that the following conditions
15  * are met:
16  * 1. Redistributions of source code must retain the above copyright
17  *    notice, this list of conditions and the following disclaimer.
18  * 2. Redistributions in binary form must reproduce the above copyright
19  *    notice, this list of conditions and the following disclaimer in the
20  *    documentation and/or other materials provided with the distribution.
21  * 3. Neither the name of the University nor the names of its contributors
22  *    may be used to endorse or promote products derived from this software
23  *    without specific prior written permission.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35  * SUCH DAMAGE.
36  *
37  *	@(#)ffs_inode.c	8.5 (Berkeley) 12/30/93
38  * $FreeBSD$
39  */
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/mount.h>
44 #include <sys/bio.h>
45 #include <sys/buf2.h>
46 #include <sys/endian.h>
47 #include <sys/vnode.h>
48 #include <sys/malloc.h>
49 
50 #include <vm/vm.h>
51 #include <vm/vm_extern.h>
52 
53 #include <vfs/ext2fs/fs.h>
54 #include <vfs/ext2fs/inode.h>
55 #include <vfs/ext2fs/ext2_mount.h>
56 #include <vfs/ext2fs/ext2fs.h>
57 #include <vfs/ext2fs/ext2_extern.h>
58 
59 /*
60  * Update the access, modified, and inode change times as specified by the
61  * IN_ACCESS, IN_UPDATE, and IN_CHANGE flags respectively.  Write the inode
62  * to disk if the IN_MODIFIED flag is set (it may be set initially, or by
63  * the timestamp update).  The IN_LAZYMOD flag is set to force a write
64  * later if not now.  If we write now, then clear both IN_MODIFIED and
65  * IN_LAZYMOD to reflect the presumably successful write, and if waitfor is
66  * set, then wait for the write to complete.
67  */
68 int
69 ext2_update(struct vnode *vp, int waitfor)
70 {
71 	struct m_ext2fs *fs;
72 	struct buf *bp;
73 	struct inode *ip;
74 	int error;
75 
76 	ASSERT_VOP_ELOCKED(vp, "ext2_update");
77 	ext2_itimes(vp);
78 	ip = VTOI(vp);
79 	if ((ip->i_flag & IN_MODIFIED) == 0 && waitfor == 0)
80 		return (0);
81 	ip->i_flag &= ~(IN_LAZYACCESS | IN_LAZYMOD | IN_MODIFIED);
82 	fs = ip->i_e2fs;
83 	if (fs->e2fs_ronly)
84 		return (0);
85 	if ((error = bread(ip->i_devvp,
86 	    fsbtodoff(fs, ino_to_fsba(fs, ip->i_number)),
87 	    (int)fs->e2fs_bsize, &bp)) != 0) {
88 		brelse(bp);
89 		return (error);
90 	}
91 	error = ext2_i2ei(ip, (struct ext2fs_dinode *)((char *)bp->b_data +
92 	    EXT2_INODE_SIZE(fs) * ino_to_fsbo(fs, ip->i_number)));
93 	if (error) {
94 		brelse(bp);
95 		return (error);
96 	}
97 	if (waitfor && !DOINGASYNC(vp))
98 		return (bwrite(bp));
99 	else {
100 		bdwrite(bp);
101 		return (0);
102 	}
103 }
104 
105 #define	SINGLE	0	/* index of single indirect block */
106 #define	DOUBLE	1	/* index of double indirect block */
107 #define	TRIPLE	2	/* index of triple indirect block */
108 
109 /*
110  * Release blocks associated with the inode ip and stored in the indirect
111  * block bn.  Blocks are free'd in LIFO order up to (but not including)
112  * lastbn.  If level is greater than SINGLE, the block is an indirect block
113  * and recursive calls to indirtrunc must be used to cleanse other indirect
114  * blocks.
115  *
116  * NB: triple indirect blocks are untested.
117  */
118 static int
119 ext2_indirtrunc(struct inode *ip, daddr_t lbn, daddr_t dbn,
120     daddr_t lastbn, int level, e4fs_daddr_t *countp)
121 {
122 	struct buf *bp;
123 	struct m_ext2fs *fs = ip->i_e2fs;
124 	struct vnode *vp;
125 	e2fs_daddr_t *bap, *copy;
126 	int i, nblocks, error = 0, allerror = 0;
127 	e2fs_lbn_t nb, nlbn, last;
128 	e4fs_daddr_t blkcount, factor, blocksreleased = 0;
129 
130 	/*
131 	 * Calculate index in current block of last
132 	 * block to be kept.  -1 indicates the entire
133 	 * block so we need not calculate the index.
134 	 */
135 	factor = 1;
136 	for (i = SINGLE; i < level; i++)
137 		factor *= NINDIR(fs);
138 	last = lastbn;
139 	if (lastbn > 0)
140 		last /= factor;
141 	nblocks = btodb(fs->e2fs_bsize);
142 	/*
143 	 * Get buffer of block pointers, zero those entries corresponding
144 	 * to blocks to be free'd, and update on disk copy first.  Since
145 	 * double(triple) indirect before single(double) indirect, calls
146 	 * to bmap on these blocks will fail.  However, we already have
147 	 * the on disk address, so we have to set the b_blkno field
148 	 * explicitly instead of letting bread do everything for us.
149 	 */
150 	vp = ITOV(ip);
151 	bp = getblk(vp, lblktodoff(fs, lbn), (int)fs->e2fs_bsize, 0, 0);
152 	if ((bp->b_flags & B_CACHE) == 0) {
153 		bp->b_flags &= ~(B_ERROR | B_INVAL);
154 		bp->b_cmd = BUF_CMD_READ;
155 		if (bp->b_bcount > bp->b_bufsize)
156 			panic("ext2_indirtrunc: bad buffer size");
157 		bp->b_bio2.bio_offset = dbtodoff(fs, dbn);
158 		bp->b_bio1.bio_done = biodone_sync;
159 		bp->b_bio1.bio_flags |= BIO_SYNC;
160 		vfs_busy_pages(bp->b_vp, bp);
161 		vn_strategy(vp, &bp->b_bio1);
162 		error = biowait(&bp->b_bio1, "biord");
163 	}
164 	if (error) {
165 		brelse(bp);
166 		*countp = 0;
167 		return (error);
168 	}
169 	bap = (e2fs_daddr_t *)bp->b_data;
170 	copy = malloc(fs->e2fs_bsize, M_TEMP, M_WAITOK);
171 	bcopy((caddr_t)bap, (caddr_t)copy, (u_int)fs->e2fs_bsize);
172 	bzero((caddr_t)&bap[last + 1],
173 	    (NINDIR(fs) - (last + 1)) * sizeof(e2fs_daddr_t));
174 	if (last == -1)
175 		bp->b_flags |= B_INVAL;
176 	if (DOINGASYNC(vp)) {
177 		bdwrite(bp);
178 	} else {
179 		error = bwrite(bp);
180 		if (error)
181 			allerror = error;
182 	}
183 	bap = copy;
184 
185 	/*
186 	 * Recursively free totally unused blocks.
187 	 */
188 	for (i = NINDIR(fs) - 1, nlbn = lbn + 1 - i * factor; i > last;
189 	    i--, nlbn += factor) {
190 		nb = le32toh(bap[i]);
191 		if (nb == 0)
192 			continue;
193 		if (level > SINGLE) {
194 			if ((error = ext2_indirtrunc(ip, nlbn,
195 			    fsbtodb(fs, nb), (int32_t)-1, level - 1, &blkcount)) != 0)
196 				allerror = error;
197 			blocksreleased += blkcount;
198 		}
199 		ext2_blkfree(ip, nb, fs->e2fs_bsize);
200 		blocksreleased += nblocks;
201 	}
202 
203 	/*
204 	 * Recursively free last partial block.
205 	 */
206 	if (level > SINGLE && lastbn >= 0) {
207 		last = lastbn % factor;
208 		nb = le32toh(bap[i]);
209 		if (nb != 0) {
210 			if ((error = ext2_indirtrunc(ip, nlbn, fsbtodb(fs, nb),
211 			    last, level - 1, &blkcount)) != 0)
212 				allerror = error;
213 			blocksreleased += blkcount;
214 		}
215 	}
216 	free(copy, M_TEMP);
217 	*countp = blocksreleased;
218 	return (allerror);
219 }
220 
221 /*
222  * Truncate the inode oip to at most length size, freeing the
223  * disk blocks.
224  */
225 static int
226 ext2_ind_truncate(struct vnode *vp, off_t length, int flags, struct ucred *cred)
227 {
228 	struct vnode *ovp = vp;
229 	e4fs_daddr_t lastblock;
230 	struct inode *oip;
231 	e4fs_daddr_t bn, lbn, lastiblock[EXT2_NIADDR], indir_lbn[EXT2_NIADDR];
232 	uint32_t oldblks[EXT2_NDADDR + EXT2_NIADDR];
233 	uint32_t newblks[EXT2_NDADDR + EXT2_NIADDR];
234 	struct m_ext2fs *fs;
235 	struct buf *bp;
236 	int offset, size, level;
237 	e4fs_daddr_t count, nblocks, blocksreleased = 0;
238 	int error, i, allerror;
239 	off_t osize;
240 
241 	oip = VTOI(ovp);
242 
243 	fs = oip->i_e2fs;
244 	osize = oip->i_size;
245 	/*
246 	 * Lengthen the size of the file. We must ensure that the
247 	 * last byte of the file is allocated. Since the smallest
248 	 * value of osize is 0, length will be at least 1.
249 	 */
250 	if (osize < length) {
251 		if (length > oip->i_e2fs->e2fs_maxfilesize)
252 			return (EFBIG);
253 		vnode_pager_setsize(ovp, length);
254 		offset = blkoff(fs, length - 1);
255 		lbn = lblkno(fs, length - 1);
256 		flags |= BA_CLRBUF;
257 		error = ext2_balloc(oip, lbn, offset + 1, cred, &bp, flags);
258 		if (error) {
259 			vnode_pager_setsize(vp, osize);
260 			return (error);
261 		}
262 		oip->i_size = length;
263 		if (bp->b_bufsize == fs->e2fs_bsize)
264 			bp->b_flags |= B_CLUSTEROK;
265 		if (flags & IO_SYNC)
266 			bwrite(bp);
267 		else if (DOINGASYNC(ovp))
268 			bdwrite(bp);
269 		else
270 			bawrite(bp);
271 		oip->i_flag |= IN_CHANGE | IN_UPDATE;
272 		return (ext2_update(ovp, !DOINGASYNC(ovp)));
273 	}
274 	/*
275 	 * Shorten the size of the file. If the file is not being
276 	 * truncated to a block boundary, the contents of the
277 	 * partial block following the end of the file must be
278 	 * zero'ed in case it ever become accessible again because
279 	 * of subsequent file growth.
280 	 */
281 	/* I don't understand the comment above */
282 	offset = blkoff(fs, length);
283 	if (offset == 0) {
284 		oip->i_size = length;
285 	} else {
286 		lbn = lblkno(fs, length);
287 		flags |= BA_CLRBUF;
288 		error = ext2_balloc(oip, lbn, offset, cred, &bp, flags);
289 		if (error)
290 			return (error);
291 		oip->i_size = length;
292 		size = blksize(fs, oip, lbn);
293 		bzero((char *)bp->b_data + offset, (u_int)(size - offset));
294 		allocbuf(bp, size);
295 		if (bp->b_bufsize == fs->e2fs_bsize)
296 			bp->b_flags |= B_CLUSTEROK;
297 		if (flags & IO_SYNC)
298 			bwrite(bp);
299 		else if (DOINGASYNC(ovp))
300 			bdwrite(bp);
301 		else
302 			bawrite(bp);
303 	}
304 	/*
305 	 * Calculate index into inode's block list of
306 	 * last direct and indirect blocks (if any)
307 	 * which we want to keep.  Lastblock is -1 when
308 	 * the file is truncated to 0.
309 	 */
310 	lastblock = lblkno(fs, length + fs->e2fs_bsize - 1) - 1;
311 	lastiblock[SINGLE] = lastblock - EXT2_NDADDR;
312 	lastiblock[DOUBLE] = lastiblock[SINGLE] - NINDIR(fs);
313 	lastiblock[TRIPLE] = lastiblock[DOUBLE] - NINDIR(fs) * NINDIR(fs);
314 	nblocks = btodb(fs->e2fs_bsize);
315 	/*
316 	 * Update file and block pointers on disk before we start freeing
317 	 * blocks.  If we crash before free'ing blocks below, the blocks
318 	 * will be returned to the free list.  lastiblock values are also
319 	 * normalized to -1 for calls to ext2_indirtrunc below.
320 	 */
321 	for (level = TRIPLE; level >= SINGLE; level--) {
322 		oldblks[EXT2_NDADDR + level] = oip->i_ib[level];
323 		if (lastiblock[level] < 0) {
324 			oip->i_ib[level] = 0;
325 			lastiblock[level] = -1;
326 		}
327 	}
328 	for (i = 0; i < EXT2_NDADDR; i++) {
329 		oldblks[i] = oip->i_db[i];
330 		if (i > lastblock)
331 			oip->i_db[i] = 0;
332 	}
333 	oip->i_flag |= IN_CHANGE | IN_UPDATE;
334 	allerror = ext2_update(ovp, !DOINGASYNC(ovp));
335 
336 	/*
337 	 * Having written the new inode to disk, save its new configuration
338 	 * and put back the old block pointers long enough to process them.
339 	 * Note that we save the new block configuration so we can check it
340 	 * when we are done.
341 	 */
342 	for (i = 0; i < EXT2_NDADDR; i++) {
343 		newblks[i] = oip->i_db[i];
344 		oip->i_db[i] = oldblks[i];
345 	}
346 	for (i = 0; i < EXT2_NIADDR; i++) {
347 		newblks[EXT2_NDADDR + i] = oip->i_ib[i];
348 		oip->i_ib[i] = oldblks[EXT2_NDADDR + i];
349 	}
350 	oip->i_size = osize;
351 	error = vtruncbuf(ovp, length, (int)fs->e2fs_bsize);
352 	if (error && (allerror == 0))
353 		allerror = error;
354 	vnode_pager_setsize(ovp, length);
355 
356 	/*
357 	 * Indirect blocks first.
358 	 */
359 	indir_lbn[SINGLE] = -EXT2_NDADDR;
360 	indir_lbn[DOUBLE] = indir_lbn[SINGLE] - NINDIR(fs) - 1;
361 	indir_lbn[TRIPLE] = indir_lbn[DOUBLE] - NINDIR(fs) * NINDIR(fs) - 1;
362 	for (level = TRIPLE; level >= SINGLE; level--) {
363 		bn = oip->i_ib[level];
364 		if (bn != 0) {
365 			error = ext2_indirtrunc(oip, indir_lbn[level],
366 			    fsbtodb(fs, bn), lastiblock[level], level, &count);
367 			if (error)
368 				allerror = error;
369 			blocksreleased += count;
370 			if (lastiblock[level] < 0) {
371 				oip->i_ib[level] = 0;
372 				ext2_blkfree(oip, bn, fs->e2fs_fsize);
373 				blocksreleased += nblocks;
374 			}
375 		}
376 		if (lastiblock[level] >= 0)
377 			goto done;
378 	}
379 
380 	/*
381 	 * All whole direct blocks or frags.
382 	 */
383 	for (i = EXT2_NDADDR - 1; i > lastblock; i--) {
384 		long bsize;
385 
386 		bn = oip->i_db[i];
387 		if (bn == 0)
388 			continue;
389 		oip->i_db[i] = 0;
390 		bsize = blksize(fs, oip, i);
391 		ext2_blkfree(oip, bn, bsize);
392 		blocksreleased += btodb(bsize);
393 	}
394 	if (lastblock < 0)
395 		goto done;
396 
397 	/*
398 	 * Finally, look for a change in size of the
399 	 * last direct block; release any frags.
400 	 */
401 	bn = oip->i_db[lastblock];
402 	if (bn != 0) {
403 		long oldspace, newspace;
404 
405 		/*
406 		 * Calculate amount of space we're giving
407 		 * back as old block size minus new block size.
408 		 */
409 		oldspace = blksize(fs, oip, lastblock);
410 		oip->i_size = length;
411 		newspace = blksize(fs, oip, lastblock);
412 		if (newspace == 0)
413 			panic("ext2_truncate: newspace");
414 		if (oldspace - newspace > 0) {
415 			/*
416 			 * Block number of space to be free'd is
417 			 * the old block # plus the number of frags
418 			 * required for the storage we're keeping.
419 			 */
420 			bn += numfrags(fs, newspace);
421 			ext2_blkfree(oip, bn, oldspace - newspace);
422 			blocksreleased += btodb(oldspace - newspace);
423 		}
424 	}
425 done:
426 #ifdef INVARIANTS
427 	for (level = SINGLE; level <= TRIPLE; level++)
428 		if (newblks[EXT2_NDADDR + level] != oip->i_ib[level])
429 			panic("itrunc1");
430 	for (i = 0; i < EXT2_NDADDR; i++)
431 		if (newblks[i] != oip->i_db[i])
432 			panic("itrunc2");
433 #endif	/* INVARIANTS */
434 	/*
435 	 * Put back the real size.
436 	 */
437 	oip->i_size = length;
438 	if (oip->i_blocks >= blocksreleased)
439 		oip->i_blocks -= blocksreleased;
440 	else				/* sanity */
441 		oip->i_blocks = 0;
442 	oip->i_flag |= IN_CHANGE;
443 	vnode_pager_setsize(ovp, length);
444 	return (allerror);
445 }
446 
447 static int
448 ext2_ext_truncate(struct vnode *vp, off_t length, int flags, struct ucred *cred)
449 {
450 	return (EINVAL);
451 }
452 
453 /*
454  * Truncate the inode ip to at most length size, freeing the
455  * disk blocks.
456  */
457 int
458 ext2_truncate(struct vnode *vp, off_t length, int flags, struct ucred *cred)
459 {
460 	struct inode *ip;
461 	int error;
462 
463 	ASSERT_VOP_LOCKED(vp, "ext2_truncate");
464 
465 	if (length < 0)
466 		return (EINVAL);
467 
468 	ip = VTOI(vp);
469 	if (vp->v_type == VLNK &&
470 	    ip->i_size < vp->v_mount->mnt_maxsymlinklen) {
471 #ifdef INVARIANTS
472 		if (length != 0)
473 			panic("ext2_truncate: partial truncate of symlink");
474 #endif
475 		bzero((char *)&ip->i_shortlink, (u_int)ip->i_size);
476 		ip->i_size = 0;
477 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
478 		return (ext2_update(vp, 1));
479 	}
480 	if (ip->i_size == length) {
481 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
482 		return (ext2_update(vp, 0));
483 	}
484 
485 	if (ip->i_flag & IN_E4EXTENTS)
486 		error = ext2_ext_truncate(vp, length, flags, cred);
487 	else
488 		error = ext2_ind_truncate(vp, length, flags, cred);
489 
490 	return (error);
491 }
492 
493 /*
494  *	discard preallocated blocks
495  */
496 int
497 ext2_inactive(struct vop_inactive_args *ap)
498 {
499 	struct vnode *vp = ap->a_vp;
500 	struct inode *ip = VTOI(vp);
501 	int mode, error = 0;
502 
503 	if (prtactive && VREFCNT(vp) > 1)
504 		vprint("ext2_inactive: pushing active", vp);
505 
506 	/*
507 	 * Ignore inodes related to stale file handles.
508 	 */
509 	if (ip == NULL || ip->i_mode == 0)
510 		goto out;
511 	if (ip->i_nlink <= 0 && (vp->v_mount->mnt_flag & MNT_RDONLY) == 0) {
512 		error = ext2_truncate(vp, (off_t)0, 0, NOCRED);
513 		if (!(ip->i_flag & IN_E4EXTENTS))
514 			ip->i_rdev = 0;
515 		mode = ip->i_mode;
516 		ip->i_mode = 0;
517 		ip->i_flag |= IN_CHANGE | IN_UPDATE;
518 		ext2_vfree(vp, ip->i_number, mode);
519 	}
520 	if (ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE))
521 		ext2_update(vp, 0);
522 out:
523 	/*
524 	 * If we are done with the inode, reclaim it
525 	 * so that it can be reused immediately.
526 	 */
527 	if (ip == NULL || ip->i_mode == 0)
528 		vrecycle(vp);
529 	return (error);
530 }
531 
532 /*
533  * Reclaim an inode so that it can be used for other purposes.
534  */
535 int
536 ext2_reclaim(struct vop_reclaim_args *ap)
537 {
538 	struct inode *ip;
539 	struct vnode *vp = ap->a_vp;
540 
541 	if (prtactive && VREFCNT(vp) > 1)
542 		vprint("ext2_reclaim: pushing active", vp);
543 
544 	ip = VTOI(vp);
545 	if (ip && (ip->i_flag & IN_LAZYMOD)) {
546 		ip->i_flag |= IN_MODIFIED;
547 		ext2_update(vp, 0);
548 	}
549 
550 #ifdef INVARIANTS
551 	if (ip && (ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_MODIFIED | IN_UPDATE))) {
552 		printf("WARNING: INODE %ld flags %08x: modified inode being released!\n",
553 		    (long)ip->i_number, (int)ip->i_flag);
554 		ip->i_flag |= IN_MODIFIED;
555 		ext2_update(vp, 0);
556 	}
557 #endif
558 	/*
559 	 * Remove the inode from its hash chain and purge namecache
560 	 * data associated with the vnode.
561 	 */
562 	vp->v_data = NULL;
563 	if (ip) {
564 		ext2_ihashrem(ip);
565 		if (ip->i_devvp) {
566 			vrele(ip->i_devvp);
567 			//ip->i_devvp = 0; /* ip->i_ump->um_devvp */
568 		}
569 		free(ip, M_EXT2NODE);
570 	}
571 	return (0);
572 }
573