xref: /netbsd-src/sbin/dump/traverse.c (revision ae1bfcddc410612bc8c58b807e1830becb69a24c)
1 /*-
2  * Copyright (c) 1980, 1988, 1991 The Regents of the University of California.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 /* from: static char sccsid[] = "@(#)traverse.c	5.21 (Berkeley) 7/19/92"; */
36 static char *rcsid = "$Id: traverse.c,v 1.3 1994/04/25 18:22:50 cgd Exp $";
37 #endif /* not lint */
38 
39 #ifdef sunos
40 #include <stdio.h>
41 #include <ctype.h>
42 #include <sys/param.h>
43 #include <ufs/fs.h>
44 #else
45 #include <sys/param.h>
46 #include <ufs/fs.h>
47 #endif
48 #include <sys/time.h>
49 #include <sys/stat.h>
50 #include <ufs/dir.h>
51 #include <ufs/dinode.h>
52 #include <protocols/dumprestore.h>
53 #ifdef __STDC__
54 #include <unistd.h>
55 #include <string.h>
56 #endif
57 #include "dump.h"
58 
59 void	dmpindir();
60 #define	HASDUMPEDFILE	0x1
61 #define	HASSUBDIRS	0x2
62 
63 /*
64  * This is an estimation of the number of TP_BSIZE blocks in the file.
65  * It estimates the number of blocks in files with holes by assuming
66  * that all of the blocks accounted for by di_blocks are data blocks
67  * (when some of the blocks are usually used for indirect pointers);
68  * hence the estimate may be high.
69  */
70 long
71 blockest(dp)
72 	register struct dinode *dp;
73 {
74 	long blkest, sizeest;
75 
76 	/*
77 	 * dp->di_size is the size of the file in bytes.
78 	 * dp->di_blocks stores the number of sectors actually in the file.
79 	 * If there are more sectors than the size would indicate, this just
80 	 *	means that there are indirect blocks in the file or unused
81 	 *	sectors in the last file block; we can safely ignore these
82 	 *	(blkest = sizeest below).
83 	 * If the file is bigger than the number of sectors would indicate,
84 	 *	then the file has holes in it.	In this case we must use the
85 	 *	block count to estimate the number of data blocks used, but
86 	 *	we use the actual size for estimating the number of indirect
87 	 *	dump blocks (sizeest vs. blkest in the indirect block
88 	 *	calculation).
89 	 */
90 	blkest = howmany(dbtob(dp->di_blocks), TP_BSIZE);
91 	sizeest = howmany(dp->di_size, TP_BSIZE);
92 	if (blkest > sizeest)
93 		blkest = sizeest;
94 	if (dp->di_size > sblock->fs_bsize * NDADDR) {
95 		/* calculate the number of indirect blocks on the dump tape */
96 		blkest +=
97 			howmany(sizeest - NDADDR * sblock->fs_bsize / TP_BSIZE,
98 			TP_NINDIR);
99 	}
100 	return (blkest + 1);
101 }
102 
103 /*
104  * Dump pass 1.
105  *
106  * Walk the inode list for a filesystem to find all allocated inodes
107  * that have been modified since the previous dump time. Also, find all
108  * the directories in the filesystem.
109  */
110 mapfiles(maxino, tapesize)
111 	ino_t maxino;
112 	long *tapesize;
113 {
114 	register int mode;
115 	register ino_t ino;
116 	register struct dinode *dp;
117 	int anydirskipped = 0;
118 
119 	for (ino = ROOTINO; ino < maxino; ino++) {
120 		dp = getino(ino);
121 		if ((mode = (dp->di_mode & IFMT)) == 0)
122 			continue;
123 		SETINO(ino, usedinomap);
124 		if (mode == IFDIR)
125 			SETINO(ino, dumpdirmap);
126 		if ((dp->di_mtime.ts_sec >= spcl.c_ddate ||
127 		    dp->di_ctime.ts_sec >= spcl.c_ddate)
128 #ifdef BSD44
129 #    ifndef sunos
130 		    && (dp->di_flags & NODUMP) != NODUMP
131 #    endif /* sunos */
132 #endif /* BSD44 */
133 		    ) {
134 			SETINO(ino, dumpinomap);
135 			if (mode != IFREG && mode != IFDIR && mode != IFLNK) {
136 				*tapesize += 1;
137 				continue;
138 			}
139 			*tapesize += blockest(dp);
140 			continue;
141 		}
142 		if (mode == IFDIR)
143 			anydirskipped = 1;
144 	}
145 	/*
146 	 * Restore gets very upset if the root is not dumped,
147 	 * so ensure that it always is dumped.
148 	 */
149 	SETINO(ROOTINO, dumpinomap);
150 	return (anydirskipped);
151 }
152 
153 /*
154  * Dump pass 2.
155  *
156  * Scan each directory on the filesystem to see if it has any modified
157  * files in it. If it does, and has not already been added to the dump
158  * list (because it was itself modified), then add it. If a directory
159  * has not been modified itself, contains no modified files and has no
160  * subdirectories, then it can be deleted from the dump list and from
161  * the list of directories. By deleting it from the list of directories,
162  * its parent may now qualify for the same treatment on this or a later
163  * pass using this algorithm.
164  */
165 mapdirs(maxino, tapesize)
166 	ino_t maxino;
167 	long *tapesize;
168 {
169 	register struct	dinode *dp;
170 	register int i, isdir;
171 	register char *map;
172 	register ino_t ino;
173 	long filesize;
174 	int ret, change = 0;
175 
176 	for (map = dumpdirmap, ino = 0; ino < maxino; ) {
177 		if ((ino % NBBY) == 0)
178 			isdir = *map++;
179 		else
180 			isdir >>= 1;
181 		ino++;
182 		if ((isdir & 1) == 0 || TSTINO(ino, dumpinomap))
183 			continue;
184 		dp = getino(ino);
185 		filesize = dp->di_size;
186 		for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) {
187 			if (dp->di_db[i] != 0)
188 				ret |= searchdir(ino, dp->di_db[i],
189 					(long)dblksize(sblock, dp, i),
190 					filesize);
191 			if (ret & HASDUMPEDFILE)
192 				filesize = 0;
193 			else
194 				filesize -= sblock->fs_bsize;
195 		}
196 		for (i = 0; filesize > 0 && i < NIADDR; i++) {
197 			if (dp->di_ib[i] == 0)
198 				continue;
199 			ret |= dirindir(ino, dp->di_ib[i], i, &filesize);
200 		}
201 		if (ret & HASDUMPEDFILE) {
202 			SETINO(ino, dumpinomap);
203 			*tapesize += blockest(dp);
204 			change = 1;
205 			continue;
206 		}
207 		if ((ret & HASSUBDIRS) == 0) {
208 			if (!TSTINO(ino, dumpinomap)) {
209 				CLRINO(ino, dumpdirmap);
210 				change = 1;
211 			}
212 		}
213 	}
214 	return (change);
215 }
216 
217 /*
218  * Read indirect blocks, and pass the data blocks to be searched
219  * as directories. Quit as soon as any entry is found that will
220  * require the directory to be dumped.
221  */
222 dirindir(ino, blkno, ind_level, filesize)
223 	ino_t ino;
224 	daddr_t blkno;
225 	int ind_level;
226 	long *filesize;
227 {
228 	int ret = 0;
229 	register int i;
230 	daddr_t	idblk[MAXNINDIR];
231 
232 	bread(fsbtodb(sblock, blkno), (char *)idblk, (int)sblock->fs_bsize);
233 	if (ind_level <= 0) {
234 		for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
235 			blkno = idblk[i];
236 			if (blkno != 0)
237 				ret |= searchdir(ino, blkno, sblock->fs_bsize,
238 					*filesize);
239 			if (ret & HASDUMPEDFILE)
240 				*filesize = 0;
241 			else
242 				*filesize -= sblock->fs_bsize;
243 		}
244 		return (ret);
245 	}
246 	ind_level--;
247 	for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
248 		blkno = idblk[i];
249 		if (blkno != 0)
250 			ret |= dirindir(ino, blkno, ind_level, filesize);
251 	}
252 	return (ret);
253 }
254 
255 /*
256  * Scan a disk block containing directory information looking to see if
257  * any of the entries are on the dump list and to see if the directory
258  * contains any subdirectories.
259  */
260 searchdir(ino, blkno, size, filesize)
261 	ino_t ino;
262 	daddr_t blkno;
263 	register long size;
264 	long filesize;
265 {
266 	register struct direct *dp;
267 	register long loc, ret = 0;
268 	char dblk[MAXBSIZE];
269 
270 	bread(fsbtodb(sblock, blkno), dblk, (int)size);
271 	if (filesize < size)
272 		size = filesize;
273 	for (loc = 0; loc < size; ) {
274 		dp = (struct direct *)(dblk + loc);
275 		if (dp->d_reclen == 0) {
276 			msg("corrupted directory, inumber %d\n", ino);
277 			break;
278 		}
279 		loc += dp->d_reclen;
280 		if (dp->d_ino == 0)
281 			continue;
282 		if (dp->d_name[0] == '.') {
283 			if (dp->d_name[1] == '\0')
284 				continue;
285 			if (dp->d_name[1] == '.' && dp->d_name[2] == '\0')
286 				continue;
287 		}
288 		if (TSTINO(dp->d_ino, dumpinomap)) {
289 			ret |= HASDUMPEDFILE;
290 			if (ret & HASSUBDIRS)
291 				break;
292 		}
293 		if (TSTINO(dp->d_ino, dumpdirmap)) {
294 			ret |= HASSUBDIRS;
295 			if (ret & HASDUMPEDFILE)
296 				break;
297 		}
298 	}
299 	return (ret);
300 }
301 
302 /*
303  * Dump passes 3 and 4.
304  *
305  * Dump the contents of an inode to tape.
306  */
307 void
308 dumpino(dp, ino)
309 	register struct dinode *dp;
310 	ino_t ino;
311 {
312 	int ind_level, cnt;
313 	long size;
314 	char buf[TP_BSIZE];
315 
316 	if (newtape) {
317 		newtape = 0;
318 		dumpmap(dumpinomap, TS_BITS, ino);
319 	}
320 	CLRINO(ino, dumpinomap);
321 	spcl.c_dinode = *dp;
322 	spcl.c_type = TS_INODE;
323 	spcl.c_count = 0;
324 
325 	switch (IFTODT(dp->di_mode)) {
326 
327 	case DT_UNKNOWN:
328 		/*
329 		 * Freed inode.
330 		 */
331 		return;
332 
333 	case DT_LNK:
334 #ifdef BSD44
335 		/*
336 		 * Check for short symbolic link.
337 		 */
338 		if (dp->di_size > 0 &&
339 		    dp->di_size < sblock->fs_maxsymlinklen) {
340 			spcl.c_addr[0] = 1;
341 			spcl.c_count = 1;
342 			writeheader(ino);
343 			bcopy((caddr_t)dp->di_shortlink, buf,
344 			    (u_long)dp->di_size);
345 			buf[dp->di_size] = '\0';
346 			writerec(buf, 0);
347 			return;
348 		}
349 #endif
350 #ifdef NetBSD
351 		if (DFASTLINK(*dp)) {
352 			spcl.c_addr[0] = 1;
353 			spcl.c_count = 1;
354 			writeheader(ino);
355 			bcopy((caddr_t)dp->di_symlink, buf,
356 			    (u_long)dp->di_size);
357 			buf[dp->di_size] = '\0';
358 			writerec(buf, 0);
359 			return;
360 		}
361 #endif
362 		/* fall through */
363 
364 	case DT_DIR:
365 	case DT_REG:
366 		if (dp->di_size > 0)
367 			break;
368 		/* fall through */
369 
370 	case DT_FIFO:
371 	case DT_SOCK:
372 	case DT_CHR:
373 	case DT_BLK:
374 		writeheader(ino);
375 		return;
376 
377 	default:
378 		msg("Warning: undefined file type 0%o\n", dp->di_mode & IFMT);
379 		return;
380 	}
381 
382 	if (dp->di_size > NDADDR * sblock->fs_bsize)
383 		cnt = NDADDR * sblock->fs_frag;
384 	else
385 		cnt = howmany(dp->di_size, sblock->fs_fsize);
386 	blksout(&dp->di_db[0], cnt, ino);
387 	if ((size = dp->di_size - NDADDR * sblock->fs_bsize) <= 0)
388 		return;
389 	for (ind_level = 0; ind_level < NIADDR; ind_level++) {
390 		dmpindir(ino, dp->di_ib[ind_level], ind_level, &size);
391 		if (size <= 0)
392 			return;
393 	}
394 }
395 
396 /*
397  * Read indirect blocks, and pass the data blocks to be dumped.
398  */
399 void
400 dmpindir(ino, blk, ind_level, size)
401 	ino_t ino;
402 	daddr_t blk;
403 	int ind_level;
404 	long *size;
405 {
406 	int i, cnt;
407 	daddr_t idblk[MAXNINDIR];
408 
409 	if (blk != 0)
410 		bread(fsbtodb(sblock, blk), (char *)idblk, (int) sblock->fs_bsize);
411 	else
412 		bzero((char *)idblk, (int)sblock->fs_bsize);
413 	if (ind_level <= 0) {
414 		if (*size < NINDIR(sblock) * sblock->fs_bsize)
415 			cnt = howmany(*size, sblock->fs_fsize);
416 		else
417 			cnt = NINDIR(sblock) * sblock->fs_frag;
418 		*size -= NINDIR(sblock) * sblock->fs_bsize;
419 		blksout(&idblk[0], cnt, ino);
420 		return;
421 	}
422 	ind_level--;
423 	for (i = 0; i < NINDIR(sblock); i++) {
424 		dmpindir(ino, idblk[i], ind_level, size);
425 		if (*size <= 0)
426 			return;
427 	}
428 }
429 
430 /*
431  * Collect up the data into tape record sized buffers and output them.
432  */
433 void
434 blksout(blkp, frags, ino)
435 	daddr_t *blkp;
436 	int frags;
437 	ino_t ino;
438 {
439 	register daddr_t *bp;
440 	int i, j, count, blks, tbperdb;
441 
442 	blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
443 	tbperdb = sblock->fs_bsize >> tp_bshift;
444 	for (i = 0; i < blks; i += TP_NINDIR) {
445 		if (i + TP_NINDIR > blks)
446 			count = blks;
447 		else
448 			count = i + TP_NINDIR;
449 		for (j = i; j < count; j++)
450 			if (blkp[j / tbperdb] != 0)
451 				spcl.c_addr[j - i] = 1;
452 			else
453 				spcl.c_addr[j - i] = 0;
454 		spcl.c_count = count - i;
455 		writeheader(ino);
456 		bp = &blkp[i / tbperdb];
457 		for (j = i; j < count; j += tbperdb, bp++)
458 			if (*bp != 0)
459 				if (j + tbperdb <= count)
460 					dumpblock(*bp, (int)sblock->fs_bsize);
461 				else
462 					dumpblock(*bp, (count - j) * TP_BSIZE);
463 		spcl.c_type = TS_ADDR;
464 	}
465 }
466 
467 /*
468  * Dump a map to the tape.
469  */
470 void
471 dumpmap(map, type, ino)
472 	char *map;
473 	int type;
474 	ino_t ino;
475 {
476 	register int i;
477 	char *cp;
478 
479 	spcl.c_type = type;
480 	spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE);
481 	writeheader(ino);
482 	for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE)
483 		writerec(cp, 0);
484 }
485 
486 /*
487  * Write a header record to the dump tape.
488  */
489 void
490 writeheader(ino)
491 	ino_t ino;
492 {
493 	register long sum, cnt, *lp;
494 
495 	spcl.c_inumber = ino;
496 	spcl.c_magic = NFS_MAGIC;
497 	spcl.c_checksum = 0;
498 	lp = (long *)&spcl;
499 	sum = 0;
500 	cnt = sizeof(union u_spcl) / (4 * sizeof(long));
501 	while (--cnt >= 0) {
502 		sum += *lp++;
503 		sum += *lp++;
504 		sum += *lp++;
505 		sum += *lp++;
506 	}
507 	spcl.c_checksum = CHECKSUM - sum;
508 	writerec((char *)&spcl, 1);
509 }
510 
511 struct dinode *
512 getino(inum)
513 	ino_t inum;
514 {
515 	static daddr_t minino, maxino;
516 	static struct dinode inoblock[MAXINOPB];
517 
518 	curino = inum;
519 	if (inum >= minino && inum < maxino)
520 		return (&inoblock[inum - minino]);
521 	bread(fsbtodb(sblock, itod(sblock, inum)), (char *)inoblock,
522 	    (int)sblock->fs_bsize);
523 	minino = inum - (inum % INOPB(sblock));
524 	maxino = minino + INOPB(sblock);
525 	return (&inoblock[inum - minino]);
526 }
527 
528 /*
529  * Read a chunk of data from the disk.
530  * Try to recover from hard errors by reading in sector sized pieces.
531  * Error recovery is attempted at most BREADEMAX times before seeking
532  * consent from the operator to continue.
533  */
534 int	breaderrors = 0;
535 #define	BREADEMAX 32
536 
537 void
538 bread(blkno, buf, size)
539 	daddr_t blkno;
540 	char *buf;
541 	int size;
542 {
543 	int cnt, i;
544 	extern int errno;
545 
546 loop:
547 	if ((int)lseek(diskfd, ((off_t)blkno << dev_bshift), 0) < 0)
548 		msg("bread: lseek fails\n");
549 	if ((cnt = read(diskfd, buf, size)) == size)
550 		return;
551 	if (blkno + (size / dev_bsize) > fsbtodb(sblock, sblock->fs_size)) {
552 		/*
553 		 * Trying to read the final fragment.
554 		 *
555 		 * NB - dump only works in TP_BSIZE blocks, hence
556 		 * rounds `dev_bsize' fragments up to TP_BSIZE pieces.
557 		 * It should be smarter about not actually trying to
558 		 * read more than it can get, but for the time being
559 		 * we punt and scale back the read only when it gets
560 		 * us into trouble. (mkm 9/25/83)
561 		 */
562 		size -= dev_bsize;
563 		goto loop;
564 	}
565 	if (cnt == -1)
566 		msg("read error from %s: %s: [block %d]: count=%d\n",
567 			disk, strerror(errno), blkno, size);
568 	else
569 		msg("short read error from %s: [block %d]: count=%d, got=%d\n",
570 			disk, blkno, size, cnt);
571 	if (++breaderrors > BREADEMAX) {
572 		msg("More than %d block read errors from %d\n",
573 			BREADEMAX, disk);
574 		broadcast("DUMP IS AILING!\n");
575 		msg("This is an unrecoverable error.\n");
576 		if (!query("Do you want to attempt to continue?")){
577 			dumpabort(0);
578 			/*NOTREACHED*/
579 		} else
580 			breaderrors = 0;
581 	}
582 	/*
583 	 * Zero buffer, then try to read each sector of buffer separately.
584 	 */
585 	bzero(buf, size);
586 	for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
587 		if ((int)lseek(diskfd, ((off_t)blkno << dev_bshift), 0) < 0)
588 			msg("bread: lseek2 fails!\n");
589 		if ((cnt = read(diskfd, buf, (int)dev_bsize)) == dev_bsize)
590 			continue;
591 		if (cnt == -1) {
592 			msg("read error from %s: %s: [sector %d]: count=%d\n",
593 				disk, strerror(errno), blkno, dev_bsize);
594 			continue;
595 		}
596 		msg("short read error from %s: [sector %d]: count=%d, got=%d\n",
597 			disk, blkno, dev_bsize, cnt);
598 	}
599 }
600