xref: /netbsd-src/sys/lib/libsa/ufs.c (revision b8c616269f5ebf18ab2e35cb8099d683130a177c)
1 /*	$NetBSD: ufs.c,v 1.31 2003/01/24 21:55:18 fvdl Exp $	*/
2 
3 /*-
4  * Copyright (c) 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * This code is derived from software contributed to Berkeley by
8  * The Mach Operating System project at Carnegie-Mellon University.
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 University of
21  *	California, Berkeley and its contributors.
22  * 4. Neither the name of the University nor the names of its contributors
23  *    may be used to endorse or promote products derived from this software
24  *    without specific prior written permission.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
27  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
28  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
29  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
30  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
31  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
32  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
33  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
34  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
36  * SUCH DAMAGE.
37  *
38  *
39  * Copyright (c) 1990, 1991 Carnegie Mellon University
40  * All Rights Reserved.
41  *
42  * Author: David Golub
43  *
44  * Permission to use, copy, modify and distribute this software and its
45  * documentation is hereby granted, provided that both the copyright
46  * notice and this permission notice appear in all copies of the
47  * software, derivative works or modified versions, and any portions
48  * thereof, and that both notices appear in supporting documentation.
49  *
50  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
51  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
52  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
53  *
54  * Carnegie Mellon requests users of this software to return to
55  *
56  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
57  *  School of Computer Science
58  *  Carnegie Mellon University
59  *  Pittsburgh PA 15213-3890
60  *
61  * any improvements or extensions that they make and grant Carnegie the
62  * rights to redistribute these changes.
63  */
64 
65 /*
66  * XXX NOTE: ufs.c (FFS) and lfs.c (LFS) should eventually use much common
67  * XXX code.  until then, the two files should be easily diffable.
68  */
69 
70 /*
71  *	Stand-alone file reading package.
72  */
73 
74 #include <sys/param.h>
75 #include <sys/time.h>
76 #include <ufs/ufs/dinode.h>
77 #include <ufs/ufs/dir.h>
78 #include <ufs/ffs/fs.h>
79 #ifdef _STANDALONE
80 #include <lib/libkern/libkern.h>
81 #else
82 #include <string.h>
83 inline u_int
84 max(a, b)
85         u_int a, b;
86 {
87         return (a > b ? a : b);
88 }
89 #endif
90 
91 #include "stand.h"
92 #include "ufs.h"
93 
94 #if defined(LIBSA_FS_SINGLECOMPONENT) && !defined(LIBSA_NO_FS_SYMLINK)
95 #define LIBSA_NO_FS_SYMLINK
96 #endif
97 #if defined(COMPAT_UFS) && defined(LIBSA_NO_COMPAT_UFS)
98 #undef COMPAT_UFS
99 #endif
100 
101 
102 /*
103  * In-core open file.
104  */
105 struct file {
106 	off_t		f_seekp;	/* seek pointer */
107 	struct fs	*f_fs;		/* pointer to super-block */
108 	struct dinode	f_di;		/* copy of on-disk inode */
109 	unsigned int	f_nindir[NIADDR];
110 					/* number of blocks mapped by
111 					   indirect block at level i */
112 	char		*f_blk[NIADDR];	/* buffer for indirect block at
113 					   level i */
114 	size_t		f_blksize[NIADDR];
115 					/* size of buffer */
116 	daddr_t		f_blkno[NIADDR];/* disk address of block in buffer */
117 	char		*f_buf;		/* buffer for data block */
118 	size_t		f_buf_size;	/* size of data block */
119 	daddr_t		f_buf_blkno;	/* block number of data block */
120 };
121 
122 static int	read_inode __P((ino_t, struct open_file *));
123 static int	block_map __P((struct open_file *, daddr_t, daddr_t *));
124 static int	buf_read_file __P((struct open_file *, char **, size_t *));
125 static int	search_directory __P((char *, struct open_file *, ino_t *));
126 #ifdef COMPAT_UFS
127 static void	ffs_oldfscompat __P((struct fs *));
128 #endif
129 
130 /*
131  * Read a new inode into a file structure.
132  */
133 static int
134 read_inode(inumber, f)
135 	ino_t inumber;
136 	struct open_file *f;
137 {
138 	struct file *fp = (struct file *)f->f_fsdata;
139 	struct fs *fs = fp->f_fs;
140 	char *buf;
141 	size_t rsize;
142 	int rc;
143 
144 	/*
145 	 * Read inode and save it.
146 	 */
147 	buf = alloc(fs->fs_bsize);
148 #if !defined(LIBSA_NO_TWIDDLE)
149 	twiddle();
150 #endif
151 	rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
152 		fsbtodb(fs, ino_to_fsba(fs, inumber)), fs->fs_bsize,
153 		buf, &rsize);
154 	if (rc)
155 		goto out;
156 	if (rsize != fs->fs_bsize) {
157 		rc = EIO;
158 		goto out;
159 	}
160 
161 	{
162 		struct dinode *dp;
163 
164 		dp = (struct dinode *)buf;
165 		fp->f_di = dp[ino_to_fsbo(fs, inumber)];
166 	}
167 
168 	/*
169 	 * Clear out the old buffers
170 	 */
171 	{
172 		int level;
173 
174 		for (level = 0; level < NIADDR; level++)
175 			fp->f_blkno[level] = -1;
176 		fp->f_buf_blkno = -1;
177 	}
178 out:
179 	free(buf, fs->fs_bsize);
180 	return (rc);
181 }
182 
183 /*
184  * Given an offset in a file, find the disk block number that
185  * contains that block.
186  */
187 static int
188 block_map(f, file_block, disk_block_p)
189 	struct open_file *f;
190 	daddr_t file_block;
191 	daddr_t *disk_block_p;	/* out */
192 {
193 	struct file *fp = (struct file *)f->f_fsdata;
194 	struct fs *fs = fp->f_fs;
195 	int level;
196 	int idx;
197 	daddr_t ind_block_num;
198 	/* XXX ondisk32 */
199 	int32_t *ind_p;
200 	int rc;
201 
202 	/*
203 	 * Index structure of an inode:
204 	 *
205 	 * di_db[0..NDADDR-1]	hold block numbers for blocks
206 	 *			0..NDADDR-1
207 	 *
208 	 * di_ib[0]		index block 0 is the single indirect block
209 	 *			holds block numbers for blocks
210 	 *			NDADDR .. NDADDR + NINDIR(fs)-1
211 	 *
212 	 * di_ib[1]		index block 1 is the double indirect block
213 	 *			holds block numbers for INDEX blocks for blocks
214 	 *			NDADDR + NINDIR(fs) ..
215 	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2 - 1
216 	 *
217 	 * di_ib[2]		index block 2 is the triple indirect block
218 	 *			holds block numbers for double-indirect
219 	 *			blocks for blocks
220 	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2 ..
221 	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2
222 	 *				+ NINDIR(fs)**3 - 1
223 	 */
224 
225 	if (file_block < NDADDR) {
226 		/* Direct block. */
227 		*disk_block_p = fp->f_di.di_db[file_block];
228 		return (0);
229 	}
230 
231 	file_block -= NDADDR;
232 
233 	/*
234 	 * nindir[0] = NINDIR
235 	 * nindir[1] = NINDIR**2
236 	 * nindir[2] = NINDIR**3
237 	 *	etc
238 	 */
239 	for (level = 0; level < NIADDR; level++) {
240 		if (file_block < fp->f_nindir[level])
241 			break;
242 		file_block -= fp->f_nindir[level];
243 	}
244 	if (level == NIADDR) {
245 		/* Block number too high */
246 		return (EFBIG);
247 	}
248 
249 	ind_block_num = fp->f_di.di_ib[level];
250 
251 	for (; level >= 0; level--) {
252 		if (ind_block_num == 0) {
253 			*disk_block_p = 0;	/* missing */
254 			return (0);
255 		}
256 
257 		if (fp->f_blkno[level] != ind_block_num) {
258 			if (fp->f_blk[level] == (char *)0)
259 				fp->f_blk[level] =
260 					alloc(fs->fs_bsize);
261 #if !defined(LIBSA_NO_TWIDDLE)
262 			twiddle();
263 #endif
264 			rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
265 				fsbtodb(fp->f_fs, ind_block_num),
266 				fs->fs_bsize,
267 				fp->f_blk[level],
268 				&fp->f_blksize[level]);
269 			if (rc)
270 				return (rc);
271 			if (fp->f_blksize[level] != fs->fs_bsize)
272 				return (EIO);
273 			fp->f_blkno[level] = ind_block_num;
274 		}
275 
276 		/* XXX ondisk32 */
277 		ind_p = (int32_t *)fp->f_blk[level];
278 
279 		if (level > 0) {
280 			idx = file_block / fp->f_nindir[level - 1];
281 			file_block %= fp->f_nindir[level - 1];
282 		} else
283 			idx = file_block;
284 
285 		ind_block_num = ind_p[idx];
286 	}
287 
288 	*disk_block_p = ind_block_num;
289 
290 	return (0);
291 }
292 
293 /*
294  * Read a portion of a file into an internal buffer.  Return
295  * the location in the buffer and the amount in the buffer.
296  */
297 static int
298 buf_read_file(f, buf_p, size_p)
299 	struct open_file *f;
300 	char **buf_p;		/* out */
301 	size_t *size_p;		/* out */
302 {
303 	struct file *fp = (struct file *)f->f_fsdata;
304 	struct fs *fs = fp->f_fs;
305 	long off;
306 	daddr_t file_block;
307 	daddr_t	disk_block;
308 	size_t block_size;
309 	int rc;
310 
311 	off = blkoff(fs, fp->f_seekp);
312 	file_block = lblkno(fs, fp->f_seekp);
313 	block_size = dblksize(fs, &fp->f_di, file_block);
314 
315 	if (file_block != fp->f_buf_blkno) {
316 		rc = block_map(f, file_block, &disk_block);
317 		if (rc)
318 			return (rc);
319 
320 		if (fp->f_buf == (char *)0)
321 			fp->f_buf = alloc(fs->fs_bsize);
322 
323 		if (disk_block == 0) {
324 			bzero(fp->f_buf, block_size);
325 			fp->f_buf_size = block_size;
326 		} else {
327 #if !defined(LIBSA_NO_TWIDDLE)
328 			twiddle();
329 #endif
330 			rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
331 				fsbtodb(fs, disk_block),
332 				block_size, fp->f_buf, &fp->f_buf_size);
333 			if (rc)
334 				return (rc);
335 		}
336 
337 		fp->f_buf_blkno = file_block;
338 	}
339 
340 	/*
341 	 * Return address of byte in buffer corresponding to
342 	 * offset, and size of remainder of buffer after that
343 	 * byte.
344 	 */
345 	*buf_p = fp->f_buf + off;
346 	*size_p = block_size - off;
347 
348 	/*
349 	 * But truncate buffer at end of file.
350 	 */
351 	if (*size_p > fp->f_di.di_size - fp->f_seekp)
352 		*size_p = fp->f_di.di_size - fp->f_seekp;
353 
354 	return (0);
355 }
356 
357 /*
358  * Search a directory for a name and return its
359  * i_number.
360  */
361 static int
362 search_directory(name, f, inumber_p)
363 	char *name;
364 	struct open_file *f;
365 	ino_t *inumber_p;		/* out */
366 {
367 	struct file *fp = (struct file *)f->f_fsdata;
368 	struct direct *dp;
369 	struct direct *edp;
370 	char *buf;
371 	size_t buf_size;
372 	int namlen, length;
373 	int rc;
374 
375 	length = strlen(name);
376 
377 	fp->f_seekp = 0;
378 	while (fp->f_seekp < fp->f_di.di_size) {
379 		rc = buf_read_file(f, &buf, &buf_size);
380 		if (rc)
381 			return (rc);
382 
383 		dp = (struct direct *)buf;
384 		edp = (struct direct *)(buf + buf_size);
385 		while (dp < edp) {
386 			if (dp->d_ino == (ino_t)0)
387 				goto next;
388 #if BYTE_ORDER == LITTLE_ENDIAN
389 			if (fp->f_fs->fs_maxsymlinklen <= 0)
390 				namlen = dp->d_type;
391 			else
392 #endif
393 				namlen = dp->d_namlen;
394 			if (namlen == length &&
395 			    !strcmp(name, dp->d_name)) {
396 				/* found entry */
397 				*inumber_p = dp->d_ino;
398 				return (0);
399 			}
400 		next:
401 			dp = (struct direct *)((char *)dp + dp->d_reclen);
402 		}
403 		fp->f_seekp += buf_size;
404 	}
405 	return (ENOENT);
406 }
407 
408 /*
409  * Open a file.
410  */
411 int
412 ufs_open(path, f)
413 	char *path;
414 	struct open_file *f;
415 {
416 #ifndef LIBSA_FS_SINGLECOMPONENT
417 	char *cp, *ncp;
418 	int c;
419 #endif
420 	ino_t inumber;
421 	struct file *fp;
422 	struct fs *fs;
423 	int rc;
424 	size_t buf_size;
425 #ifndef LIBSA_NO_FS_SYMLINK
426 	ino_t parent_inumber;
427 	int nlinks = 0;
428 	char namebuf[MAXPATHLEN+1];
429 	char *buf = NULL;
430 #endif
431 
432 	/* allocate file system specific data structure */
433 	fp = alloc(sizeof(struct file));
434 	bzero(fp, sizeof(struct file));
435 	f->f_fsdata = (void *)fp;
436 
437 	/* allocate space and read super block */
438 	fs = alloc(SBSIZE);
439 	fp->f_fs = fs;
440 #if !defined(LIBSA_NO_TWIDDLE)
441 	twiddle();
442 #endif
443 	rc = DEV_STRATEGY(f->f_dev)(f->f_devdata, F_READ,
444 		SBLOCK, SBSIZE, (char *)fs, &buf_size);
445 	if (rc)
446 		goto out;
447 
448 	if (buf_size != SBSIZE || fs->fs_magic != FS_MAGIC ||
449 	    fs->fs_bsize > MAXBSIZE || fs->fs_bsize < sizeof(struct fs)) {
450 		rc = EINVAL;
451 		goto out;
452 	}
453 #ifdef COMPAT_UFS
454 	ffs_oldfscompat(fs);
455 #endif
456 
457 	/*
458 	 * Calculate indirect block levels.
459 	 */
460 	{
461 		int mult;
462 		int level;
463 
464 		mult = 1;
465 		for (level = 0; level < NIADDR; level++) {
466 			mult *= NINDIR(fs);
467 			fp->f_nindir[level] = mult;
468 		}
469 	}
470 
471 	inumber = ROOTINO;
472 	if ((rc = read_inode(inumber, f)) != 0)
473 		goto out;
474 
475 #ifndef LIBSA_FS_SINGLECOMPONENT
476 	cp = path;
477 	while (*cp) {
478 
479 		/*
480 		 * Remove extra separators
481 		 */
482 		while (*cp == '/')
483 			cp++;
484 		if (*cp == '\0')
485 			break;
486 
487 		/*
488 		 * Check that current node is a directory.
489 		 */
490 		if ((fp->f_di.di_mode & IFMT) != IFDIR) {
491 			rc = ENOTDIR;
492 			goto out;
493 		}
494 
495 		/*
496 		 * Get next component of path name.
497 		 */
498 		{
499 			int len = 0;
500 
501 			ncp = cp;
502 			while ((c = *cp) != '\0' && c != '/') {
503 				if (++len > MAXNAMLEN) {
504 					rc = ENOENT;
505 					goto out;
506 				}
507 				cp++;
508 			}
509 			*cp = '\0';
510 		}
511 
512 		/*
513 		 * Look up component in current directory.
514 		 * Save directory inumber in case we find a
515 		 * symbolic link.
516 		 */
517 #ifndef LIBSA_NO_FS_SYMLINK
518 		parent_inumber = inumber;
519 #endif
520 		rc = search_directory(ncp, f, &inumber);
521 		*cp = c;
522 		if (rc)
523 			goto out;
524 
525 		/*
526 		 * Open next component.
527 		 */
528 		if ((rc = read_inode(inumber, f)) != 0)
529 			goto out;
530 
531 #ifndef LIBSA_NO_FS_SYMLINK
532 		/*
533 		 * Check for symbolic link.
534 		 */
535 		if ((fp->f_di.di_mode & IFMT) == IFLNK) {
536 			int link_len = fp->f_di.di_size;
537 			int len;
538 
539 			len = strlen(cp);
540 
541 			if (link_len + len > MAXPATHLEN ||
542 			    ++nlinks > MAXSYMLINKS) {
543 				rc = ENOENT;
544 				goto out;
545 			}
546 
547 			bcopy(cp, &namebuf[link_len], len + 1);
548 
549 			if (link_len < fs->fs_maxsymlinklen) {
550 				bcopy(fp->f_di.di_shortlink, namebuf,
551 				      (unsigned) link_len);
552 			} else {
553 				/*
554 				 * Read file for symbolic link
555 				 */
556 				size_t buf_size;
557 				daddr_t	disk_block;
558 				struct fs *fs = fp->f_fs;
559 
560 				if (!buf)
561 					buf = alloc(fs->fs_bsize);
562 				rc = block_map(f, (daddr_t)0, &disk_block);
563 				if (rc)
564 					goto out;
565 
566 #if !defined(LIBSA_NO_TWIDDLE)
567 				twiddle();
568 #endif
569 				rc = DEV_STRATEGY(f->f_dev)(f->f_devdata,
570 					F_READ, fsbtodb(fs, disk_block),
571 					fs->fs_bsize, buf, &buf_size);
572 				if (rc)
573 					goto out;
574 
575 				bcopy((char *)buf, namebuf, (unsigned)link_len);
576 			}
577 
578 			/*
579 			 * If relative pathname, restart at parent directory.
580 			 * If absolute pathname, restart at root.
581 			 */
582 			cp = namebuf;
583 			if (*cp != '/')
584 				inumber = parent_inumber;
585 			else
586 				inumber = (ino_t)ROOTINO;
587 
588 			if ((rc = read_inode(inumber, f)) != 0)
589 				goto out;
590 		}
591 #endif	/* !LIBSA_NO_FS_SYMLINK */
592 	}
593 
594 	/*
595 	 * Found terminal component.
596 	 */
597 	rc = 0;
598 
599 #else /* !LIBSA_FS_SINGLECOMPONENT */
600 
601 	/* look up component in the current (root) directory */
602 	rc = search_directory(path, f, &inumber);
603 	if (rc)
604 		goto out;
605 
606 	/* open it */
607 	rc = read_inode(inumber, f);
608 
609 #endif /* !LIBSA_FS_SINGLECOMPONENT */
610 
611         fp->f_seekp = 0;		/* reset seek pointer */
612 
613 out:
614 #ifndef LIBSA_NO_FS_SYMLINK
615 	if (buf)
616 		free(buf, fs->fs_bsize);
617 #endif
618 	if (rc) {
619 		if (fp->f_buf)
620 			free(fp->f_buf, fp->f_fs->fs_bsize);
621 		free(fp->f_fs, SBSIZE);
622 		free(fp, sizeof(struct file));
623 	}
624 	return (rc);
625 }
626 
627 #ifndef LIBSA_NO_FS_CLOSE
628 int
629 ufs_close(f)
630 	struct open_file *f;
631 {
632 	struct file *fp = (struct file *)f->f_fsdata;
633 	int level;
634 
635 	f->f_fsdata = (void *)0;
636 	if (fp == (struct file *)0)
637 		return (0);
638 
639 	for (level = 0; level < NIADDR; level++) {
640 		if (fp->f_blk[level])
641 			free(fp->f_blk[level], fp->f_fs->fs_bsize);
642 	}
643 	if (fp->f_buf)
644 		free(fp->f_buf, fp->f_fs->fs_bsize);
645 	free(fp->f_fs, SBSIZE);
646 	free(fp, sizeof(struct file));
647 	return (0);
648 }
649 #endif /* !LIBSA_NO_FS_CLOSE */
650 
651 /*
652  * Copy a portion of a file into kernel memory.
653  * Cross block boundaries when necessary.
654  */
655 int
656 ufs_read(f, start, size, resid)
657 	struct open_file *f;
658 	void *start;
659 	size_t size;
660 	size_t *resid;	/* out */
661 {
662 	struct file *fp = (struct file *)f->f_fsdata;
663 	size_t csize;
664 	char *buf;
665 	size_t buf_size;
666 	int rc = 0;
667 	char *addr = start;
668 
669 	while (size != 0) {
670 		if (fp->f_seekp >= fp->f_di.di_size)
671 			break;
672 
673 		rc = buf_read_file(f, &buf, &buf_size);
674 		if (rc)
675 			break;
676 
677 		csize = size;
678 		if (csize > buf_size)
679 			csize = buf_size;
680 
681 		bcopy(buf, addr, csize);
682 
683 		fp->f_seekp += csize;
684 		addr += csize;
685 		size -= csize;
686 	}
687 	if (resid)
688 		*resid = size;
689 	return (rc);
690 }
691 
692 /*
693  * Not implemented.
694  */
695 #ifndef LIBSA_NO_FS_WRITE
696 int
697 ufs_write(f, start, size, resid)
698 	struct open_file *f;
699 	void *start;
700 	size_t size;
701 	size_t *resid;	/* out */
702 {
703 
704 	return (EROFS);
705 }
706 #endif /* !LIBSA_NO_FS_WRITE */
707 
708 #ifndef LIBSA_NO_FS_SEEK
709 off_t
710 ufs_seek(f, offset, where)
711 	struct open_file *f;
712 	off_t offset;
713 	int where;
714 {
715 	struct file *fp = (struct file *)f->f_fsdata;
716 
717 	switch (where) {
718 	case SEEK_SET:
719 		fp->f_seekp = offset;
720 		break;
721 	case SEEK_CUR:
722 		fp->f_seekp += offset;
723 		break;
724 	case SEEK_END:
725 		fp->f_seekp = fp->f_di.di_size - offset;
726 		break;
727 	default:
728 		return (-1);
729 	}
730 	return (fp->f_seekp);
731 }
732 #endif /* !LIBSA_NO_FS_SEEK */
733 
734 int
735 ufs_stat(f, sb)
736 	struct open_file *f;
737 	struct stat *sb;
738 {
739 	struct file *fp = (struct file *)f->f_fsdata;
740 
741 	/* only important stuff */
742 	sb->st_mode = fp->f_di.di_mode;
743 	sb->st_uid = fp->f_di.di_uid;
744 	sb->st_gid = fp->f_di.di_gid;
745 	sb->st_size = fp->f_di.di_size;
746 	return (0);
747 }
748 
749 #ifdef COMPAT_UFS
750 /*
751  * Sanity checks for old file systems.
752  *
753  * XXX - goes away some day.
754  */
755 static void
756 ffs_oldfscompat(fs)
757 	struct fs *fs;
758 {
759 	int i;
760 
761 	fs->fs_npsect = max(fs->fs_npsect, fs->fs_nsect);	/* XXX */
762 	fs->fs_interleave = max(fs->fs_interleave, 1);		/* XXX */
763 	if (fs->fs_postblformat == FS_42POSTBLFMT)		/* XXX */
764 		fs->fs_nrpos = 8;				/* XXX */
765 	if (fs->fs_inodefmt < FS_44INODEFMT) {			/* XXX */
766 		quad_t sizepb = fs->fs_bsize;			/* XXX */
767 								/* XXX */
768 		fs->fs_maxfilesize = fs->fs_bsize * NDADDR - 1;	/* XXX */
769 		for (i = 0; i < NIADDR; i++) {			/* XXX */
770 			sizepb *= NINDIR(fs);			/* XXX */
771 			fs->fs_maxfilesize += sizepb;		/* XXX */
772 		}						/* XXX */
773 		fs->fs_qbmask = ~fs->fs_bmask;			/* XXX */
774 		fs->fs_qfmask = ~fs->fs_fmask;			/* XXX */
775 	}							/* XXX */
776 }
777 #endif
778