xref: /titanic_52/usr/src/boot/lib/libstand/ufs.c (revision 4a5d661a82b942b6538acd26209d959ce98b593a)
1 /*	$NetBSD: ufs.c,v 1.20 1998/03/01 07:15:39 ross Exp $	*/
2 
3 /*-
4  * Copyright (c) 2002 Networks Associates Technology, Inc.
5  * All rights reserved.
6  *
7  * This software was developed for the FreeBSD Project by Marshall
8  * Kirk McKusick and Network Associates Laboratories, the Security
9  * Research Division of Network Associates, Inc. under DARPA/SPAWAR
10  * contract N66001-01-C-8035 ("CBOSS"), as part of the DARPA CHATS
11  * research program
12  *
13  * Copyright (c) 1982, 1989, 1993
14  *	The Regents of the University of California.  All rights reserved.
15  *
16  * This code is derived from software contributed to Berkeley by
17  * The Mach Operating System project at Carnegie-Mellon University.
18  *
19  * Redistribution and use in source and binary forms, with or without
20  * modification, are permitted provided that the following conditions
21  * are met:
22  * 1. Redistributions of source code must retain the above copyright
23  *    notice, this list of conditions and the following disclaimer.
24  * 2. Redistributions in binary form must reproduce the above copyright
25  *    notice, this list of conditions and the following disclaimer in the
26  *    documentation and/or other materials provided with the distribution.
27  * 3. Neither the name of the University nor the names of its contributors
28  *    may be used to endorse or promote products derived from this software
29  *    without specific prior written permission.
30  *
31  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
41  * SUCH DAMAGE.
42  *
43  *
44  * Copyright (c) 1990, 1991 Carnegie Mellon University
45  * All Rights Reserved.
46  *
47  * Author: David Golub
48  *
49  * Permission to use, copy, modify and distribute this software and its
50  * documentation is hereby granted, provided that both the copyright
51  * notice and this permission notice appear in all copies of the
52  * software, derivative works or modified versions, and any portions
53  * thereof, and that both notices appear in supporting documentation.
54  *
55  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
56  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
57  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
58  *
59  * Carnegie Mellon requests users of this software to return to
60  *
61  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
62  *  School of Computer Science
63  *  Carnegie Mellon University
64  *  Pittsburgh PA 15213-3890
65  *
66  * any improvements or extensions that they make and grant Carnegie the
67  * rights to redistribute these changes.
68  */
69 
70 #include <sys/cdefs.h>
71 __FBSDID("$FreeBSD$");
72 
73 /*
74  *	Stand-alone file reading package.
75  */
76 
77 #include <sys/param.h>
78 #include <sys/disklabel.h>
79 #include <sys/time.h>
80 #include <ufs/ufs/dinode.h>
81 #include <ufs/ufs/dir.h>
82 #include <ufs/ffs/fs.h>
83 #include "stand.h"
84 #include "string.h"
85 
86 static int	ufs_open(const char *path, struct open_file *f);
87 static int	ufs_write(struct open_file *f, void *buf, size_t size, size_t *resid);
88 static int	ufs_close(struct open_file *f);
89 static int	ufs_read(struct open_file *f, void *buf, size_t size, size_t *resid);
90 static off_t	ufs_seek(struct open_file *f, off_t offset, int where);
91 static int	ufs_stat(struct open_file *f, struct stat *sb);
92 static int	ufs_readdir(struct open_file *f, struct dirent *d);
93 
94 struct fs_ops ufs_fsops = {
95 	"ufs",
96 	ufs_open,
97 	ufs_close,
98 	ufs_read,
99 	ufs_write,
100 	ufs_seek,
101 	ufs_stat,
102 	ufs_readdir
103 };
104 
105 /*
106  * In-core open file.
107  */
108 struct file {
109 	off_t		f_seekp;	/* seek pointer */
110 	struct fs	*f_fs;		/* pointer to super-block */
111 	union dinode {
112 		struct ufs1_dinode di1;
113 		struct ufs2_dinode di2;
114 	}		f_di;		/* copy of on-disk inode */
115 	int		f_nindir[NIADDR];
116 					/* number of blocks mapped by
117 					   indirect block at level i */
118 	char		*f_blk[NIADDR];	/* buffer for indirect block at
119 					   level i */
120 	size_t		f_blksize[NIADDR];
121 					/* size of buffer */
122 	ufs2_daddr_t	f_blkno[NIADDR];/* disk address of block in buffer */
123 	ufs2_daddr_t	f_buf_blkno;	/* block number of data block */
124 	char		*f_buf;		/* buffer for data block */
125 	size_t		f_buf_size;	/* size of data block */
126 };
127 #define DIP(fp, field) \
128 	((fp)->f_fs->fs_magic == FS_UFS1_MAGIC ? \
129 	(fp)->f_di.di1.field : (fp)->f_di.di2.field)
130 
131 static int	read_inode(ino_t, struct open_file *);
132 static int	block_map(struct open_file *, ufs2_daddr_t, ufs2_daddr_t *);
133 static int	buf_read_file(struct open_file *, char **, size_t *);
134 static int	buf_write_file(struct open_file *, char *, size_t *);
135 static int	search_directory(char *, struct open_file *, ino_t *);
136 
137 /*
138  * Read a new inode into a file structure.
139  */
140 static int
141 read_inode(inumber, f)
142 	ino_t inumber;
143 	struct open_file *f;
144 {
145 	struct file *fp = (struct file *)f->f_fsdata;
146 	struct fs *fs = fp->f_fs;
147 	char *buf;
148 	size_t rsize;
149 	int rc;
150 
151 	if (fs == NULL)
152 	    panic("fs == NULL");
153 
154 	/*
155 	 * Read inode and save it.
156 	 */
157 	buf = malloc(fs->fs_bsize);
158 	twiddle(1);
159 	rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
160 		fsbtodb(fs, ino_to_fsba(fs, inumber)), 0, fs->fs_bsize,
161 		buf, &rsize);
162 	if (rc)
163 		goto out;
164 	if (rsize != fs->fs_bsize) {
165 		rc = EIO;
166 		goto out;
167 	}
168 
169 	if (fp->f_fs->fs_magic == FS_UFS1_MAGIC)
170 		fp->f_di.di1 = ((struct ufs1_dinode *)buf)
171 		    [ino_to_fsbo(fs, inumber)];
172 	else
173 		fp->f_di.di2 = ((struct ufs2_dinode *)buf)
174 		    [ino_to_fsbo(fs, inumber)];
175 
176 	/*
177 	 * Clear out the old buffers
178 	 */
179 	{
180 		int level;
181 
182 		for (level = 0; level < NIADDR; level++)
183 			fp->f_blkno[level] = -1;
184 		fp->f_buf_blkno = -1;
185 	}
186 	fp->f_seekp = 0;
187 out:
188 	free(buf);
189 	return (rc);
190 }
191 
192 /*
193  * Given an offset in a file, find the disk block number that
194  * contains that block.
195  */
196 static int
197 block_map(f, file_block, disk_block_p)
198 	struct open_file *f;
199 	ufs2_daddr_t file_block;
200 	ufs2_daddr_t *disk_block_p;	/* out */
201 {
202 	struct file *fp = (struct file *)f->f_fsdata;
203 	struct fs *fs = fp->f_fs;
204 	int level;
205 	int idx;
206 	ufs2_daddr_t ind_block_num;
207 	int rc;
208 
209 	/*
210 	 * Index structure of an inode:
211 	 *
212 	 * di_db[0..NDADDR-1]	hold block numbers for blocks
213 	 *			0..NDADDR-1
214 	 *
215 	 * di_ib[0]		index block 0 is the single indirect block
216 	 *			holds block numbers for blocks
217 	 *			NDADDR .. NDADDR + NINDIR(fs)-1
218 	 *
219 	 * di_ib[1]		index block 1 is the double indirect block
220 	 *			holds block numbers for INDEX blocks for blocks
221 	 *			NDADDR + NINDIR(fs) ..
222 	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2 - 1
223 	 *
224 	 * di_ib[2]		index block 2 is the triple indirect block
225 	 *			holds block numbers for double-indirect
226 	 *			blocks for blocks
227 	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2 ..
228 	 *			NDADDR + NINDIR(fs) + NINDIR(fs)**2
229 	 *				+ NINDIR(fs)**3 - 1
230 	 */
231 
232 	if (file_block < NDADDR) {
233 		/* Direct block. */
234 		*disk_block_p = DIP(fp, di_db[file_block]);
235 		return (0);
236 	}
237 
238 	file_block -= NDADDR;
239 
240 	/*
241 	 * nindir[0] = NINDIR
242 	 * nindir[1] = NINDIR**2
243 	 * nindir[2] = NINDIR**3
244 	 *	etc
245 	 */
246 	for (level = 0; level < NIADDR; level++) {
247 		if (file_block < fp->f_nindir[level])
248 			break;
249 		file_block -= fp->f_nindir[level];
250 	}
251 	if (level == NIADDR) {
252 		/* Block number too high */
253 		return (EFBIG);
254 	}
255 
256 	ind_block_num = DIP(fp, di_ib[level]);
257 
258 	for (; level >= 0; level--) {
259 		if (ind_block_num == 0) {
260 			*disk_block_p = 0;	/* missing */
261 			return (0);
262 		}
263 
264 		if (fp->f_blkno[level] != ind_block_num) {
265 			if (fp->f_blk[level] == (char *)0)
266 				fp->f_blk[level] =
267 					malloc(fs->fs_bsize);
268 			twiddle(1);
269 			rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
270 				fsbtodb(fp->f_fs, ind_block_num), 0,
271 				fs->fs_bsize,
272 				fp->f_blk[level],
273 				&fp->f_blksize[level]);
274 			if (rc)
275 				return (rc);
276 			if (fp->f_blksize[level] != fs->fs_bsize)
277 				return (EIO);
278 			fp->f_blkno[level] = ind_block_num;
279 		}
280 
281 		if (level > 0) {
282 			idx = file_block / fp->f_nindir[level - 1];
283 			file_block %= fp->f_nindir[level - 1];
284 		} else
285 			idx = file_block;
286 
287 		if (fp->f_fs->fs_magic == FS_UFS1_MAGIC)
288 			ind_block_num = ((ufs1_daddr_t *)fp->f_blk[level])[idx];
289 		else
290 			ind_block_num = ((ufs2_daddr_t *)fp->f_blk[level])[idx];
291 	}
292 
293 	*disk_block_p = ind_block_num;
294 
295 	return (0);
296 }
297 
298 /*
299  * Write a portion of a file from an internal buffer.
300  */
301 static int
302 buf_write_file(f, buf_p, size_p)
303 	struct open_file *f;
304 	char *buf_p;
305 	size_t *size_p;		/* out */
306 {
307 	struct file *fp = (struct file *)f->f_fsdata;
308 	struct fs *fs = fp->f_fs;
309 	long off;
310 	ufs_lbn_t file_block;
311 	ufs2_daddr_t disk_block;
312 	size_t block_size;
313 	int rc;
314 
315 	/*
316 	 * Calculate the starting block address and offset.
317 	 */
318 	off = blkoff(fs, fp->f_seekp);
319 	file_block = lblkno(fs, fp->f_seekp);
320 	block_size = sblksize(fs, DIP(fp, di_size), file_block);
321 
322 	rc = block_map(f, file_block, &disk_block);
323 	if (rc)
324 		return (rc);
325 
326  	if (disk_block == 0)
327 		/* Because we can't allocate space on the drive */
328 		return (EFBIG);
329 
330 	/*
331 	 * Truncate buffer at end of file, and at the end of
332 	 * this block.
333 	 */
334 	if (*size_p > DIP(fp, di_size) - fp->f_seekp)
335 		*size_p = DIP(fp, di_size) - fp->f_seekp;
336 	if (*size_p > block_size - off)
337 		*size_p = block_size - off;
338 
339 	/*
340 	 * If we don't entirely occlude the block and it's not
341 	 * in memory already, read it in first.
342 	 */
343 	if (((off > 0) || (*size_p + off < block_size)) &&
344 	    (file_block != fp->f_buf_blkno)) {
345 
346 		if (fp->f_buf == (char *)0)
347 			fp->f_buf = malloc(fs->fs_bsize);
348 
349 		twiddle(8);
350 		rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
351 			fsbtodb(fs, disk_block), 0,
352 			block_size, fp->f_buf, &fp->f_buf_size);
353 		if (rc)
354 			return (rc);
355 
356 		fp->f_buf_blkno = file_block;
357 	}
358 
359 	/*
360 	 *	Copy the user data into the cached block.
361 	 */
362 	bcopy(buf_p, fp->f_buf + off, *size_p);
363 
364 	/*
365 	 *	Write the block out to storage.
366 	 */
367 
368 	twiddle(4);
369 	rc = (f->f_dev->dv_strategy)(f->f_devdata, F_WRITE,
370 		fsbtodb(fs, disk_block), 0,
371 		block_size, fp->f_buf, &fp->f_buf_size);
372 	return (rc);
373 }
374 
375 /*
376  * Read a portion of a file into an internal buffer.  Return
377  * the location in the buffer and the amount in the buffer.
378  */
379 static int
380 buf_read_file(f, buf_p, size_p)
381 	struct open_file *f;
382 	char **buf_p;		/* out */
383 	size_t *size_p;		/* out */
384 {
385 	struct file *fp = (struct file *)f->f_fsdata;
386 	struct fs *fs = fp->f_fs;
387 	long off;
388 	ufs_lbn_t file_block;
389 	ufs2_daddr_t disk_block;
390 	size_t block_size;
391 	int rc;
392 
393 	off = blkoff(fs, fp->f_seekp);
394 	file_block = lblkno(fs, fp->f_seekp);
395 	block_size = sblksize(fs, DIP(fp, di_size), file_block);
396 
397 	if (file_block != fp->f_buf_blkno) {
398 		if (fp->f_buf == (char *)0)
399 			fp->f_buf = malloc(fs->fs_bsize);
400 
401 		rc = block_map(f, file_block, &disk_block);
402 		if (rc)
403 			return (rc);
404 
405 		if (disk_block == 0) {
406 			bzero(fp->f_buf, block_size);
407 			fp->f_buf_size = block_size;
408 		} else {
409 			twiddle(4);
410 			rc = (f->f_dev->dv_strategy)(f->f_devdata,
411 				F_READ, fsbtodb(fs, disk_block), 0,
412 				block_size, fp->f_buf, &fp->f_buf_size);
413 			if (rc)
414 				return (rc);
415 		}
416 
417 		fp->f_buf_blkno = file_block;
418 	}
419 
420 	/*
421 	 * Return address of byte in buffer corresponding to
422 	 * offset, and size of remainder of buffer after that
423 	 * byte.
424 	 */
425 	*buf_p = fp->f_buf + off;
426 	*size_p = block_size - off;
427 
428 	/*
429 	 * But truncate buffer at end of file.
430 	 */
431 	if (*size_p > DIP(fp, di_size) - fp->f_seekp)
432 		*size_p = DIP(fp, di_size) - fp->f_seekp;
433 
434 	return (0);
435 }
436 
437 /*
438  * Search a directory for a name and return its
439  * i_number.
440  */
441 static int
442 search_directory(name, f, inumber_p)
443 	char *name;
444 	struct open_file *f;
445 	ino_t *inumber_p;		/* out */
446 {
447 	struct file *fp = (struct file *)f->f_fsdata;
448 	struct direct *dp;
449 	struct direct *edp;
450 	char *buf;
451 	size_t buf_size;
452 	int namlen, length;
453 	int rc;
454 
455 	length = strlen(name);
456 
457 	fp->f_seekp = 0;
458 	while (fp->f_seekp < DIP(fp, di_size)) {
459 		rc = buf_read_file(f, &buf, &buf_size);
460 		if (rc)
461 			return (rc);
462 
463 		dp = (struct direct *)buf;
464 		edp = (struct direct *)(buf + buf_size);
465 		while (dp < edp) {
466 			if (dp->d_ino == (ino_t)0)
467 				goto next;
468 			namlen = dp->d_namlen;
469 			if (namlen == length &&
470 			    !strcmp(name, dp->d_name)) {
471 				/* found entry */
472 				*inumber_p = dp->d_ino;
473 				return (0);
474 			}
475 		next:
476 			dp = (struct direct *)((char *)dp + dp->d_reclen);
477 		}
478 		fp->f_seekp += buf_size;
479 	}
480 	return (ENOENT);
481 }
482 
483 static int sblock_try[] = SBLOCKSEARCH;
484 
485 /*
486  * Open a file.
487  */
488 static int
489 ufs_open(upath, f)
490 	const char *upath;
491 	struct open_file *f;
492 {
493 	char *cp, *ncp;
494 	int c;
495 	ino_t inumber, parent_inumber;
496 	struct file *fp;
497 	struct fs *fs;
498 	int i, rc;
499 	size_t buf_size;
500 	int nlinks = 0;
501 	char namebuf[MAXPATHLEN+1];
502 	char *buf = NULL;
503 	char *path = NULL;
504 
505 	/* allocate file system specific data structure */
506 	fp = malloc(sizeof(struct file));
507 	bzero(fp, sizeof(struct file));
508 	f->f_fsdata = (void *)fp;
509 
510 	/* allocate space and read super block */
511 	fs = malloc(SBLOCKSIZE);
512 	fp->f_fs = fs;
513 	twiddle(1);
514 	/*
515 	 * Try reading the superblock in each of its possible locations.
516 	 */
517 	for (i = 0; sblock_try[i] != -1; i++) {
518 		rc = (f->f_dev->dv_strategy)(f->f_devdata, F_READ,
519 		    sblock_try[i] / DEV_BSIZE, 0, SBLOCKSIZE,
520 		    (char *)fs, &buf_size);
521 		if (rc)
522 			goto out;
523 		if ((fs->fs_magic == FS_UFS1_MAGIC ||
524 		     (fs->fs_magic == FS_UFS2_MAGIC &&
525 		      fs->fs_sblockloc == sblock_try[i])) &&
526 		    buf_size == SBLOCKSIZE &&
527 		    fs->fs_bsize <= MAXBSIZE &&
528 		    fs->fs_bsize >= sizeof(struct fs))
529 			break;
530 	}
531 	if (sblock_try[i] == -1) {
532 		rc = EINVAL;
533 		goto out;
534 	}
535 	/*
536 	 * Calculate indirect block levels.
537 	 */
538 	{
539 		ufs2_daddr_t mult;
540 		int level;
541 
542 		mult = 1;
543 		for (level = 0; level < NIADDR; level++) {
544 			mult *= NINDIR(fs);
545 			fp->f_nindir[level] = mult;
546 		}
547 	}
548 
549 	inumber = ROOTINO;
550 	if ((rc = read_inode(inumber, f)) != 0)
551 		goto out;
552 
553 	cp = path = strdup(upath);
554 	if (path == NULL) {
555 	    rc = ENOMEM;
556 	    goto out;
557 	}
558 	while (*cp) {
559 
560 		/*
561 		 * Remove extra separators
562 		 */
563 		while (*cp == '/')
564 			cp++;
565 		if (*cp == '\0')
566 			break;
567 
568 		/*
569 		 * Check that current node is a directory.
570 		 */
571 		if ((DIP(fp, di_mode) & IFMT) != IFDIR) {
572 			rc = ENOTDIR;
573 			goto out;
574 		}
575 
576 		/*
577 		 * Get next component of path name.
578 		 */
579 		{
580 			int len = 0;
581 
582 			ncp = cp;
583 			while ((c = *cp) != '\0' && c != '/') {
584 				if (++len > MAXNAMLEN) {
585 					rc = ENOENT;
586 					goto out;
587 				}
588 				cp++;
589 			}
590 			*cp = '\0';
591 		}
592 
593 		/*
594 		 * Look up component in current directory.
595 		 * Save directory inumber in case we find a
596 		 * symbolic link.
597 		 */
598 		parent_inumber = inumber;
599 		rc = search_directory(ncp, f, &inumber);
600 		*cp = c;
601 		if (rc)
602 			goto out;
603 
604 		/*
605 		 * Open next component.
606 		 */
607 		if ((rc = read_inode(inumber, f)) != 0)
608 			goto out;
609 
610 		/*
611 		 * Check for symbolic link.
612 		 */
613 		if ((DIP(fp, di_mode) & IFMT) == IFLNK) {
614 			int link_len = DIP(fp, di_size);
615 			int len;
616 
617 			len = strlen(cp);
618 
619 			if (link_len + len > MAXPATHLEN ||
620 			    ++nlinks > MAXSYMLINKS) {
621 				rc = ENOENT;
622 				goto out;
623 			}
624 
625 			bcopy(cp, &namebuf[link_len], len + 1);
626 
627 			if (link_len < fs->fs_maxsymlinklen) {
628 				if (fp->f_fs->fs_magic == FS_UFS1_MAGIC)
629 					cp = (caddr_t)(fp->f_di.di1.di_db);
630 				else
631 					cp = (caddr_t)(fp->f_di.di2.di_db);
632 				bcopy(cp, namebuf, (unsigned) link_len);
633 			} else {
634 				/*
635 				 * Read file for symbolic link
636 				 */
637 				size_t buf_size;
638 				ufs2_daddr_t disk_block;
639 				struct fs *fs = fp->f_fs;
640 
641 				if (!buf)
642 					buf = malloc(fs->fs_bsize);
643 				rc = block_map(f, (ufs2_daddr_t)0, &disk_block);
644 				if (rc)
645 					goto out;
646 
647 				twiddle(1);
648 				rc = (f->f_dev->dv_strategy)(f->f_devdata,
649 					F_READ, fsbtodb(fs, disk_block), 0,
650 					fs->fs_bsize, buf, &buf_size);
651 				if (rc)
652 					goto out;
653 
654 				bcopy((char *)buf, namebuf, (unsigned)link_len);
655 			}
656 
657 			/*
658 			 * If relative pathname, restart at parent directory.
659 			 * If absolute pathname, restart at root.
660 			 */
661 			cp = namebuf;
662 			if (*cp != '/')
663 				inumber = parent_inumber;
664 			else
665 				inumber = (ino_t)ROOTINO;
666 
667 			if ((rc = read_inode(inumber, f)) != 0)
668 				goto out;
669 		}
670 	}
671 
672 	/*
673 	 * Found terminal component.
674 	 */
675 	rc = 0;
676 	fp->f_seekp = 0;
677 out:
678 	if (buf)
679 		free(buf);
680 	if (path)
681 		free(path);
682 	if (rc) {
683 		if (fp->f_buf)
684 			free(fp->f_buf);
685 		free(fp->f_fs);
686 		free(fp);
687 	}
688 	return (rc);
689 }
690 
691 static int
692 ufs_close(f)
693 	struct open_file *f;
694 {
695 	struct file *fp = (struct file *)f->f_fsdata;
696 	int level;
697 
698 	f->f_fsdata = (void *)0;
699 	if (fp == (struct file *)0)
700 		return (0);
701 
702 	for (level = 0; level < NIADDR; level++) {
703 		if (fp->f_blk[level])
704 			free(fp->f_blk[level]);
705 	}
706 	if (fp->f_buf)
707 		free(fp->f_buf);
708 	free(fp->f_fs);
709 	free(fp);
710 	return (0);
711 }
712 
713 /*
714  * Copy a portion of a file into kernel memory.
715  * Cross block boundaries when necessary.
716  */
717 static int
718 ufs_read(f, start, size, resid)
719 	struct open_file *f;
720 	void *start;
721 	size_t size;
722 	size_t *resid;	/* out */
723 {
724 	struct file *fp = (struct file *)f->f_fsdata;
725 	size_t csize;
726 	char *buf;
727 	size_t buf_size;
728 	int rc = 0;
729 	char *addr = start;
730 
731 	while (size != 0) {
732 		if (fp->f_seekp >= DIP(fp, di_size))
733 			break;
734 
735 		rc = buf_read_file(f, &buf, &buf_size);
736 		if (rc)
737 			break;
738 
739 		csize = size;
740 		if (csize > buf_size)
741 			csize = buf_size;
742 
743 		bcopy(buf, addr, csize);
744 
745 		fp->f_seekp += csize;
746 		addr += csize;
747 		size -= csize;
748 	}
749 	if (resid)
750 		*resid = size;
751 	return (rc);
752 }
753 
754 /*
755  * Write to a portion of an already allocated file.
756  * Cross block boundaries when necessary. Can not
757  * extend the file.
758  */
759 static int
760 ufs_write(f, start, size, resid)
761 	struct open_file *f;
762 	void *start;
763 	size_t size;
764 	size_t *resid;	/* out */
765 {
766 	struct file *fp = (struct file *)f->f_fsdata;
767 	size_t csize;
768 	int rc = 0;
769 	char *addr = start;
770 
771 	csize = size;
772 	while ((size != 0) && (csize != 0)) {
773 		if (fp->f_seekp >= DIP(fp, di_size))
774 			break;
775 
776 		if (csize >= 512) csize = 512; /* XXX */
777 
778 		rc = buf_write_file(f, addr, &csize);
779 		if (rc)
780 			break;
781 
782 		fp->f_seekp += csize;
783 		addr += csize;
784 		size -= csize;
785 	}
786 	if (resid)
787 		*resid = size;
788 	return (rc);
789 }
790 
791 static off_t
792 ufs_seek(f, offset, where)
793 	struct open_file *f;
794 	off_t offset;
795 	int where;
796 {
797 	struct file *fp = (struct file *)f->f_fsdata;
798 
799 	switch (where) {
800 	case SEEK_SET:
801 		fp->f_seekp = offset;
802 		break;
803 	case SEEK_CUR:
804 		fp->f_seekp += offset;
805 		break;
806 	case SEEK_END:
807 		fp->f_seekp = DIP(fp, di_size) - offset;
808 		break;
809 	default:
810 		errno = EINVAL;
811 		return (-1);
812 	}
813 	return (fp->f_seekp);
814 }
815 
816 static int
817 ufs_stat(f, sb)
818 	struct open_file *f;
819 	struct stat *sb;
820 {
821 	struct file *fp = (struct file *)f->f_fsdata;
822 
823 	/* only important stuff */
824 	sb->st_mode = DIP(fp, di_mode);
825 	sb->st_uid = DIP(fp, di_uid);
826 	sb->st_gid = DIP(fp, di_gid);
827 	sb->st_size = DIP(fp, di_size);
828 	return (0);
829 }
830 
831 static int
832 ufs_readdir(struct open_file *f, struct dirent *d)
833 {
834 	struct file *fp = (struct file *)f->f_fsdata;
835 	struct direct *dp;
836 	char *buf;
837 	size_t buf_size;
838 	int error;
839 
840 	/*
841 	 * assume that a directory entry will not be split across blocks
842 	 */
843 again:
844 	if (fp->f_seekp >= DIP(fp, di_size))
845 		return (ENOENT);
846 	error = buf_read_file(f, &buf, &buf_size);
847 	if (error)
848 		return (error);
849 	dp = (struct direct *)buf;
850 	fp->f_seekp += dp->d_reclen;
851 	if (dp->d_ino == (ino_t)0)
852 		goto again;
853 
854 	d->d_type = 0;		/* illumos ufs does not have type in direct */
855 	strcpy(d->d_name, dp->d_name);
856 	return (0);
857 }
858