xref: /freebsd/sbin/dump/traverse.c (revision 77a0943ded95b9e6438f7db70c4a28e4d93946d4)
1 /*-
2  * Copyright (c) 1980, 1988, 1991, 1993
3  *	The Regents of the University of California.  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 #if 0
36 static char sccsid[] = "@(#)traverse.c	8.7 (Berkeley) 6/15/95";
37 #endif
38 static const char rcsid[] =
39   "$FreeBSD$";
40 #endif /* not lint */
41 
42 #include <sys/param.h>
43 #include <sys/stat.h>
44 #ifdef sunos
45 #include <sys/vnode.h>
46 
47 #include <ufs/fs.h>
48 #include <ufs/fsdir.h>
49 #include <ufs/inode.h>
50 #else
51 #include <ufs/ufs/dir.h>
52 #include <ufs/ufs/dinode.h>
53 #include <ufs/ffs/fs.h>
54 #endif
55 
56 #include <protocols/dumprestore.h>
57 
58 #include <ctype.h>
59 #include <stdio.h>
60 #ifdef __STDC__
61 #include <errno.h>
62 #include <string.h>
63 #include <unistd.h>
64 #endif
65 
66 #include "dump.h"
67 
68 #define	HASDUMPEDFILE	0x1
69 #define	HASSUBDIRS	0x2
70 
71 #ifdef	FS_44INODEFMT
72 typedef	quad_t fsizeT;
73 #else
74 typedef	long fsizeT;
75 #endif
76 
77 static	int dirindir __P((ino_t ino, daddr_t blkno, int level, long *size));
78 static	void dmpindir __P((ino_t ino, daddr_t blk, int level, fsizeT *size));
79 static	int searchdir __P((ino_t ino, daddr_t blkno, long size, long filesize));
80 
81 /*
82  * This is an estimation of the number of TP_BSIZE blocks in the file.
83  * It estimates the number of blocks in files with holes by assuming
84  * that all of the blocks accounted for by di_blocks are data blocks
85  * (when some of the blocks are usually used for indirect pointers);
86  * hence the estimate may be high.
87  */
88 long
89 blockest(dp)
90 	register struct dinode *dp;
91 {
92 	long blkest, sizeest;
93 
94 	/*
95 	 * dp->di_size is the size of the file in bytes.
96 	 * dp->di_blocks stores the number of sectors actually in the file.
97 	 * If there are more sectors than the size would indicate, this just
98 	 *	means that there are indirect blocks in the file or unused
99 	 *	sectors in the last file block; we can safely ignore these
100 	 *	(blkest = sizeest below).
101 	 * If the file is bigger than the number of sectors would indicate,
102 	 *	then the file has holes in it.	In this case we must use the
103 	 *	block count to estimate the number of data blocks used, but
104 	 *	we use the actual size for estimating the number of indirect
105 	 *	dump blocks (sizeest vs. blkest in the indirect block
106 	 *	calculation).
107 	 */
108 	blkest = howmany(dbtob(dp->di_blocks), TP_BSIZE);
109 	sizeest = howmany(dp->di_size, TP_BSIZE);
110 	if (blkest > sizeest)
111 		blkest = sizeest;
112 	if (dp->di_size > sblock->fs_bsize * NDADDR) {
113 		/* calculate the number of indirect blocks on the dump tape */
114 		blkest +=
115 			howmany(sizeest - NDADDR * sblock->fs_bsize / TP_BSIZE,
116 			TP_NINDIR);
117 	}
118 	return (blkest + 1);
119 }
120 
121 /* Auxiliary macro to pick up files changed since previous dump. */
122 #define	CHANGEDSINCE(dp, t) \
123 	((dp)->di_mtime >= (t) || (dp)->di_ctime >= (t))
124 
125 /* The WANTTODUMP macro decides whether a file should be dumped. */
126 #ifdef UF_NODUMP
127 #define	WANTTODUMP(dp) \
128 	(CHANGEDSINCE(dp, spcl.c_ddate) && \
129 	 (nonodump || ((dp)->di_flags & UF_NODUMP) != UF_NODUMP))
130 #else
131 #define	WANTTODUMP(dp) CHANGEDSINCE(dp, spcl.c_ddate)
132 #endif
133 
134 /*
135  * Dump pass 1.
136  *
137  * Walk the inode list for a filesystem to find all allocated inodes
138  * that have been modified since the previous dump time. Also, find all
139  * the directories in the filesystem.
140  */
141 int
142 mapfiles(maxino, tapesize)
143 	ino_t maxino;
144 	long *tapesize;
145 {
146 	register int mode;
147 	register ino_t ino;
148 	register struct dinode *dp;
149 	int anydirskipped = 0;
150 
151 	for (ino = ROOTINO; ino < maxino; ino++) {
152 		dp = getino(ino);
153 		if ((mode = (dp->di_mode & IFMT)) == 0)
154 			continue;
155 		SETINO(ino, usedinomap);
156 		if (mode == IFDIR)
157 			SETINO(ino, dumpdirmap);
158 		if (WANTTODUMP(dp)) {
159 			SETINO(ino, dumpinomap);
160 			if (mode != IFREG && mode != IFDIR && mode != IFLNK)
161 				*tapesize += 1;
162 			else
163 				*tapesize += blockest(dp);
164 			continue;
165 		}
166 		if (mode == IFDIR)
167 			anydirskipped = 1;
168 	}
169 	/*
170 	 * Restore gets very upset if the root is not dumped,
171 	 * so ensure that it always is dumped.
172 	 */
173 	SETINO(ROOTINO, dumpinomap);
174 	return (anydirskipped);
175 }
176 
177 /*
178  * Dump pass 2.
179  *
180  * Scan each directory on the filesystem to see if it has any modified
181  * files in it. If it does, and has not already been added to the dump
182  * list (because it was itself modified), then add it. If a directory
183  * has not been modified itself, contains no modified files and has no
184  * subdirectories, then it can be deleted from the dump list and from
185  * the list of directories. By deleting it from the list of directories,
186  * its parent may now qualify for the same treatment on this or a later
187  * pass using this algorithm.
188  */
189 int
190 mapdirs(maxino, tapesize)
191 	ino_t maxino;
192 	long *tapesize;
193 {
194 	register struct	dinode *dp;
195 	register int i, isdir;
196 	register char *map;
197 	register ino_t ino;
198 	long filesize;
199 	int ret, change = 0;
200 
201 	isdir = 0;		/* XXX just to get gcc to shut up */
202 	for (map = dumpdirmap, ino = 1; ino < maxino; ino++) {
203 		if (((ino - 1) % NBBY) == 0)	/* map is offset by 1 */
204 			isdir = *map++;
205 		else
206 			isdir >>= 1;
207 		if ((isdir & 1) == 0 || TSTINO(ino, dumpinomap))
208 			continue;
209 		dp = getino(ino);
210 		filesize = dp->di_size;
211 		for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) {
212 			if (dp->di_db[i] != 0)
213 				ret |= searchdir(ino, dp->di_db[i],
214 					(long)dblksize(sblock, dp, i),
215 					filesize);
216 			if (ret & HASDUMPEDFILE)
217 				filesize = 0;
218 			else
219 				filesize -= sblock->fs_bsize;
220 		}
221 		for (i = 0; filesize > 0 && i < NIADDR; i++) {
222 			if (dp->di_ib[i] == 0)
223 				continue;
224 			ret |= dirindir(ino, dp->di_ib[i], i, &filesize);
225 		}
226 		if (ret & HASDUMPEDFILE) {
227 			SETINO(ino, dumpinomap);
228 			*tapesize += blockest(dp);
229 			change = 1;
230 			continue;
231 		}
232 		if ((ret & HASSUBDIRS) == 0) {
233 			if (!TSTINO(ino, dumpinomap)) {
234 				CLRINO(ino, dumpdirmap);
235 				change = 1;
236 			}
237 		}
238 	}
239 	return (change);
240 }
241 
242 /*
243  * Read indirect blocks, and pass the data blocks to be searched
244  * as directories. Quit as soon as any entry is found that will
245  * require the directory to be dumped.
246  */
247 static int
248 dirindir(ino, blkno, ind_level, filesize)
249 	ino_t ino;
250 	daddr_t blkno;
251 	int ind_level;
252 	long *filesize;
253 {
254 	int ret = 0;
255 	register int i;
256 	daddr_t	idblk[MAXNINDIR];
257 
258 	bread(fsbtodb(sblock, blkno), (char *)idblk, (int)sblock->fs_bsize);
259 	if (ind_level <= 0) {
260 		for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
261 			blkno = idblk[i];
262 			if (blkno != 0)
263 				ret |= searchdir(ino, blkno, sblock->fs_bsize,
264 					*filesize);
265 			if (ret & HASDUMPEDFILE)
266 				*filesize = 0;
267 			else
268 				*filesize -= sblock->fs_bsize;
269 		}
270 		return (ret);
271 	}
272 	ind_level--;
273 	for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
274 		blkno = idblk[i];
275 		if (blkno != 0)
276 			ret |= dirindir(ino, blkno, ind_level, filesize);
277 	}
278 	return (ret);
279 }
280 
281 /*
282  * Scan a disk block containing directory information looking to see if
283  * any of the entries are on the dump list and to see if the directory
284  * contains any subdirectories.
285  */
286 static int
287 searchdir(ino, blkno, size, filesize)
288 	ino_t ino;
289 	daddr_t blkno;
290 	register long size;
291 	long filesize;
292 {
293 	register struct direct *dp;
294 	register long loc, ret = 0;
295 	char dblk[MAXBSIZE];
296 
297 	bread(fsbtodb(sblock, blkno), dblk, (int)size);
298 	if (filesize < size)
299 		size = filesize;
300 	for (loc = 0; loc < size; ) {
301 		dp = (struct direct *)(dblk + loc);
302 		if (dp->d_reclen == 0) {
303 			msg("corrupted directory, inumber %d\n", ino);
304 			break;
305 		}
306 		loc += dp->d_reclen;
307 		if (dp->d_ino == 0)
308 			continue;
309 		if (dp->d_name[0] == '.') {
310 			if (dp->d_name[1] == '\0')
311 				continue;
312 			if (dp->d_name[1] == '.' && dp->d_name[2] == '\0')
313 				continue;
314 		}
315 		if (TSTINO(dp->d_ino, dumpinomap)) {
316 			ret |= HASDUMPEDFILE;
317 			if (ret & HASSUBDIRS)
318 				break;
319 		}
320 		if (TSTINO(dp->d_ino, dumpdirmap)) {
321 			ret |= HASSUBDIRS;
322 			if (ret & HASDUMPEDFILE)
323 				break;
324 		}
325 	}
326 	return (ret);
327 }
328 
329 /*
330  * Dump passes 3 and 4.
331  *
332  * Dump the contents of an inode to tape.
333  */
334 void
335 dumpino(dp, ino)
336 	register struct dinode *dp;
337 	ino_t ino;
338 {
339 	int ind_level, cnt;
340 	fsizeT size;
341 	char buf[TP_BSIZE];
342 
343 	if (newtape) {
344 		newtape = 0;
345 		dumpmap(dumpinomap, TS_BITS, ino);
346 	}
347 	CLRINO(ino, dumpinomap);
348 	spcl.c_dinode = *dp;
349 	spcl.c_type = TS_INODE;
350 	spcl.c_count = 0;
351 	switch (dp->di_mode & S_IFMT) {
352 
353 	case 0:
354 		/*
355 		 * Freed inode.
356 		 */
357 		return;
358 
359 	case S_IFLNK:
360 		/*
361 		 * Check for short symbolic link.
362 		 */
363 #ifdef FS_44INODEFMT
364 		if (dp->di_size > 0 &&
365 		    dp->di_size < sblock->fs_maxsymlinklen) {
366 			spcl.c_addr[0] = 1;
367 			spcl.c_count = 1;
368 			writeheader(ino);
369 			memmove(buf, dp->di_shortlink, (u_long)dp->di_size);
370 			buf[dp->di_size] = '\0';
371 			writerec(buf, 0);
372 			return;
373 		}
374 #endif
375 		/* fall through */
376 
377 	case S_IFDIR:
378 	case S_IFREG:
379 		if (dp->di_size > 0)
380 			break;
381 		/* fall through */
382 
383 	case S_IFIFO:
384 	case S_IFSOCK:
385 	case S_IFCHR:
386 	case S_IFBLK:
387 		writeheader(ino);
388 		return;
389 
390 	default:
391 		msg("Warning: undefined file type 0%o\n", dp->di_mode & IFMT);
392 		return;
393 	}
394 	if (dp->di_size > NDADDR * sblock->fs_bsize)
395 		cnt = NDADDR * sblock->fs_frag;
396 	else
397 		cnt = howmany(dp->di_size, sblock->fs_fsize);
398 	blksout(&dp->di_db[0], cnt, ino);
399 	if ((size = dp->di_size - NDADDR * sblock->fs_bsize) <= 0)
400 		return;
401 	for (ind_level = 0; ind_level < NIADDR; ind_level++) {
402 		dmpindir(ino, dp->di_ib[ind_level], ind_level, &size);
403 		if (size <= 0)
404 			return;
405 	}
406 }
407 
408 /*
409  * Read indirect blocks, and pass the data blocks to be dumped.
410  */
411 static void
412 dmpindir(ino, blk, ind_level, size)
413 	ino_t ino;
414 	daddr_t blk;
415 	int ind_level;
416 	fsizeT *size;
417 {
418 	int i, cnt;
419 	daddr_t idblk[MAXNINDIR];
420 
421 	if (blk != 0)
422 		bread(fsbtodb(sblock, blk), (char *)idblk, (int) sblock->fs_bsize);
423 	else
424 		memset(idblk, 0, (int)sblock->fs_bsize);
425 	if (ind_level <= 0) {
426 		if (*size < NINDIR(sblock) * sblock->fs_bsize)
427 			cnt = howmany(*size, sblock->fs_fsize);
428 		else
429 			cnt = NINDIR(sblock) * sblock->fs_frag;
430 		*size -= NINDIR(sblock) * sblock->fs_bsize;
431 		blksout(&idblk[0], cnt, ino);
432 		return;
433 	}
434 	ind_level--;
435 	for (i = 0; i < NINDIR(sblock); i++) {
436 		dmpindir(ino, idblk[i], ind_level, size);
437 		if (*size <= 0)
438 			return;
439 	}
440 }
441 
442 /*
443  * Collect up the data into tape record sized buffers and output them.
444  */
445 void
446 blksout(blkp, frags, ino)
447 	daddr_t *blkp;
448 	int frags;
449 	ino_t ino;
450 {
451 	register daddr_t *bp;
452 	int i, j, count, blks, tbperdb;
453 
454 	blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
455 	tbperdb = sblock->fs_bsize >> tp_bshift;
456 	for (i = 0; i < blks; i += TP_NINDIR) {
457 		if (i + TP_NINDIR > blks)
458 			count = blks;
459 		else
460 			count = i + TP_NINDIR;
461 		for (j = i; j < count; j++)
462 			if (blkp[j / tbperdb] != 0)
463 				spcl.c_addr[j - i] = 1;
464 			else
465 				spcl.c_addr[j - i] = 0;
466 		spcl.c_count = count - i;
467 		writeheader(ino);
468 		bp = &blkp[i / tbperdb];
469 		for (j = i; j < count; j += tbperdb, bp++)
470 			if (*bp != 0) {
471 				if (j + tbperdb <= count)
472 					dumpblock(*bp, (int)sblock->fs_bsize);
473 				else
474 					dumpblock(*bp, (count - j) * TP_BSIZE);
475 			}
476 		spcl.c_type = TS_ADDR;
477 	}
478 }
479 
480 /*
481  * Dump a map to the tape.
482  */
483 void
484 dumpmap(map, type, ino)
485 	char *map;
486 	int type;
487 	ino_t ino;
488 {
489 	register int i;
490 	char *cp;
491 
492 	spcl.c_type = type;
493 	spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE);
494 	writeheader(ino);
495 	for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE)
496 		writerec(cp, 0);
497 }
498 
499 /*
500  * Write a header record to the dump tape.
501  */
502 void
503 writeheader(ino)
504 	ino_t ino;
505 {
506 	register int32_t sum, cnt, *lp;
507 
508 	spcl.c_inumber = ino;
509 	spcl.c_magic = NFS_MAGIC;
510 	spcl.c_checksum = 0;
511 	lp = (int32_t *)&spcl;
512 	sum = 0;
513 	cnt = sizeof(union u_spcl) / (4 * sizeof(int32_t));
514 	while (--cnt >= 0) {
515 		sum += *lp++;
516 		sum += *lp++;
517 		sum += *lp++;
518 		sum += *lp++;
519 	}
520 	spcl.c_checksum = CHECKSUM - sum;
521 	writerec((char *)&spcl, 1);
522 }
523 
524 struct dinode *
525 getino(inum)
526 	ino_t inum;
527 {
528 	static daddr_t minino, maxino;
529 	static struct dinode inoblock[MAXINOPB];
530 
531 	curino = inum;
532 	if (inum >= minino && inum < maxino)
533 		return (&inoblock[inum - minino]);
534 	bread(fsbtodb(sblock, ino_to_fsba(sblock, inum)), (char *)inoblock,
535 	    (int)sblock->fs_bsize);
536 	minino = inum - (inum % INOPB(sblock));
537 	maxino = minino + INOPB(sblock);
538 	return (&inoblock[inum - minino]);
539 }
540 
541 /*
542  * Read a chunk of data from the disk.
543  * Try to recover from hard errors by reading in sector sized pieces.
544  * Error recovery is attempted at most BREADEMAX times before seeking
545  * consent from the operator to continue.
546  */
547 int	breaderrors = 0;
548 #define	BREADEMAX 32
549 
550 void
551 bread(blkno, buf, size)
552 	daddr_t blkno;
553 	char *buf;
554 	int size;
555 {
556 	int cnt, i;
557 
558 loop:
559 	if (lseek(diskfd, ((off_t)blkno << dev_bshift), 0) !=
560 						((off_t)blkno << dev_bshift))
561 		msg("bread: lseek fails\n");
562 	if ((cnt = read(diskfd, buf, size)) == size)
563 		return;
564 	if (blkno + (size / dev_bsize) > fsbtodb(sblock, sblock->fs_size)) {
565 		/*
566 		 * Trying to read the final fragment.
567 		 *
568 		 * NB - dump only works in TP_BSIZE blocks, hence
569 		 * rounds `dev_bsize' fragments up to TP_BSIZE pieces.
570 		 * It should be smarter about not actually trying to
571 		 * read more than it can get, but for the time being
572 		 * we punt and scale back the read only when it gets
573 		 * us into trouble. (mkm 9/25/83)
574 		 */
575 		size -= dev_bsize;
576 		goto loop;
577 	}
578 	if (cnt == -1)
579 		msg("read error from %s: %s: [block %d]: count=%d\n",
580 			disk, strerror(errno), blkno, size);
581 	else
582 		msg("short read error from %s: [block %d]: count=%d, got=%d\n",
583 			disk, blkno, size, cnt);
584 	if (++breaderrors > BREADEMAX) {
585 		msg("More than %d block read errors from %d\n",
586 			BREADEMAX, disk);
587 		broadcast("DUMP IS AILING!\n");
588 		msg("This is an unrecoverable error.\n");
589 		if (!query("Do you want to attempt to continue?")){
590 			dumpabort(0);
591 			/*NOTREACHED*/
592 		} else
593 			breaderrors = 0;
594 	}
595 	/*
596 	 * Zero buffer, then try to read each sector of buffer separately.
597 	 */
598 	memset(buf, 0, size);
599 	for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
600 		if (lseek(diskfd, ((off_t)blkno << dev_bshift), 0) !=
601 						((off_t)blkno << dev_bshift))
602 			msg("bread: lseek2 fails!\n");
603 		if ((cnt = read(diskfd, buf, (int)dev_bsize)) == dev_bsize)
604 			continue;
605 		if (cnt == -1) {
606 			msg("read error from %s: %s: [sector %d]: count=%d\n",
607 				disk, strerror(errno), blkno, dev_bsize);
608 			continue;
609 		}
610 		msg("short read error from %s: [sector %d]: count=%d, got=%d\n",
611 			disk, blkno, dev_bsize, cnt);
612 	}
613 }
614