xref: /dragonfly/sbin/dump/traverse.c (revision ef3ac1d1)
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. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * @(#)traverse.c	8.7 (Berkeley) 6/15/95
30  * $FreeBSD: src/sbin/dump/traverse.c,v 1.10.2.6 2003/04/14 20:10:35 johan Exp $
31  */
32 
33 #include <sys/param.h>
34 #include <sys/stat.h>
35 #ifdef sunos
36 #include <sys/vnode.h>
37 
38 #include <ufs/fs.h>
39 #include <ufs/fsdir.h>
40 #include <ufs/inode.h>
41 #else
42 #include <vfs/ufs/dir.h>
43 #include <vfs/ufs/dinode.h>
44 #include <vfs/ufs/fs.h>
45 #endif
46 
47 #include <protocols/dumprestore.h>
48 
49 #include <ctype.h>
50 #include <stdio.h>
51 #include <errno.h>
52 #include <string.h>
53 #include <unistd.h>
54 
55 #include "dump.h"
56 
57 #define	HASDUMPEDFILE	0x1
58 #define	HASSUBDIRS	0x2
59 
60 #ifdef	FS_44INODEFMT
61 typedef	quad_t fsizeT;
62 #else
63 typedef	long fsizeT;
64 #endif
65 
66 static int	dirindir(ufs1_ino_t, daddr_t, int, long *, long *, int);
67 static void	dmpindir(ufs1_ino_t, daddr_t, int, fsizeT *);
68 static	int searchdir(ufs1_ino_t, daddr_t, long, long, long *, int);
69 
70 /*
71  * This is an estimation of the number of TP_BSIZE blocks in the file.
72  * It estimates the number of blocks in files with holes by assuming
73  * that all of the blocks accounted for by di_blocks are data blocks
74  * (when some of the blocks are usually used for indirect pointers);
75  * hence the estimate may be high.
76  */
77 long
78 blockest(struct ufs1_dinode *dp)
79 {
80 	long blkest, sizeest;
81 
82 	/*
83 	 * dp->di_size is the size of the file in bytes.
84 	 * dp->di_blocks stores the number of sectors actually in the file.
85 	 * If there are more sectors than the size would indicate, this just
86 	 *	means that there are indirect blocks in the file or unused
87 	 *	sectors in the last file block; we can safely ignore these
88 	 *	(blkest = sizeest below).
89 	 * If the file is bigger than the number of sectors would indicate,
90 	 *	then the file has holes in it.	In this case we must use the
91 	 *	block count to estimate the number of data blocks used, but
92 	 *	we use the actual size for estimating the number of indirect
93 	 *	dump blocks (sizeest vs. blkest in the indirect block
94 	 *	calculation).
95 	 */
96 	blkest = howmany(dbtob(dp->di_blocks), TP_BSIZE);
97 	sizeest = howmany(dp->di_size, TP_BSIZE);
98 	if (blkest > sizeest)
99 		blkest = sizeest;
100 	if (dp->di_size > (unsigned)sblock->fs_bsize * NDADDR) {
101 		/* calculate the number of indirect blocks on the dump tape */
102 		blkest +=
103 			howmany(sizeest - NDADDR * sblock->fs_bsize / TP_BSIZE,
104 			TP_NINDIR);
105 	}
106 	return (blkest + 1);
107 }
108 
109 /* Auxiliary macro to pick up files changed since previous dump. */
110 #define	CHANGEDSINCE(dp, t) \
111 	((dp)->di_mtime >= (t) || (dp)->di_ctime >= (t))
112 
113 /* The WANTTODUMP macro decides whether a file should be dumped. */
114 #ifdef UF_NODUMP
115 #define	WANTTODUMP(dp) \
116 	(CHANGEDSINCE(dp, spcl.c_ddate) && \
117 	 (nonodump || ((dp)->di_flags & UF_NODUMP) != UF_NODUMP))
118 #else
119 #define	WANTTODUMP(dp) CHANGEDSINCE(dp, spcl.c_ddate)
120 #endif
121 
122 /*
123  * Dump pass 1.
124  *
125  * Walk the inode list for a filesystem to find all allocated inodes
126  * that have been modified since the previous dump time. Also, find all
127  * the directories in the filesystem.
128  */
129 int
130 mapfiles(ufs1_ino_t maxino, long *tape_size)
131 {
132 	int mode;
133 	ufs1_ino_t ino;
134 	struct ufs1_dinode *dp;
135 	int anydirskipped = 0;
136 
137 	for (ino = ROOTINO; ino < maxino; ino++) {
138 		dp = getino(ino);
139 		if ((mode = (dp->di_mode & IFMT)) == 0)
140 			continue;
141 		/*
142 		 * Everything must go in usedinomap so that a check
143 		 * for "in dumpdirmap but not in usedinomap" to detect
144 		 * dirs with nodump set has a chance of succeeding
145 		 * (this is used in mapdirs()).
146 		 */
147 		SETINO(ino, usedinomap);
148 		if (mode == IFDIR)
149 			SETINO(ino, dumpdirmap);
150 		if (WANTTODUMP(dp)) {
151 			SETINO(ino, dumpinomap);
152 			if (mode != IFREG && mode != IFDIR && mode != IFLNK)
153 				*tape_size += 1;
154 			else
155 				*tape_size += blockest(dp);
156 			continue;
157 		}
158 		if (mode == IFDIR) {
159 			if (!nonodump && (dp->di_flags & UF_NODUMP))
160 				CLRINO(ino, usedinomap);
161 			anydirskipped = 1;
162 		}
163 	}
164 	/*
165 	 * Restore gets very upset if the root is not dumped,
166 	 * so ensure that it always is dumped.
167 	 */
168 	SETINO(ROOTINO, dumpinomap);
169 	return (anydirskipped);
170 }
171 
172 /*
173  * Dump pass 2.
174  *
175  * Scan each directory on the filesystem to see if it has any modified
176  * files in it. If it does, and has not already been added to the dump
177  * list (because it was itself modified), then add it. If a directory
178  * has not been modified itself, contains no modified files and has no
179  * subdirectories, then it can be deleted from the dump list and from
180  * the list of directories. By deleting it from the list of directories,
181  * its parent may now qualify for the same treatment on this or a later
182  * pass using this algorithm.
183  */
184 int
185 mapdirs(ufs1_ino_t maxino, long *tape_size)
186 {
187 	struct	ufs1_dinode *dp;
188 	int isdir, nodump;
189 	unsigned int i;
190 	char *map;
191 	ufs1_ino_t ino;
192 	struct ufs1_dinode di;
193 	long filesize;
194 	int ret, change = 0;
195 
196 	isdir = 0;		/* XXX just to get gcc to shut up */
197 	for (map = dumpdirmap, ino = 1; ino < maxino; ino++) {
198 		if (((ino - 1) % NBBY) == 0)	/* map is offset by 1 */
199 			isdir = *map++;
200 		else
201 			isdir >>= 1;
202 		/*
203 		 * If a directory has been removed from usedinomap, it
204 		 * either has the nodump flag set, or has inherited
205 		 * it.  Although a directory can't be in dumpinomap if
206 		 * it isn't in usedinomap, we have to go through it to
207 		 * propagate the nodump flag.
208 		 */
209 		nodump = !nonodump && (TSTINO(ino, usedinomap) == 0);
210 		if ((isdir & 1) == 0 || (TSTINO(ino, dumpinomap) && !nodump))
211 			continue;
212 		dp = getino(ino);
213 		di = *dp;	/* inode buf may change in searchdir(). */
214 		filesize = di.di_size;
215 		for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) {
216 			if (di.di_db[i] != 0) {
217 				ret |= searchdir(ino, di.di_db[i],
218 					(long)dblksize(sblock, &di, i),
219 					filesize, tape_size, nodump);
220 			}
221 			if (ret & HASDUMPEDFILE)
222 				filesize = 0;
223 			else
224 				filesize -= sblock->fs_bsize;
225 		}
226 		for (i = 0; filesize > 0 && i < NIADDR; i++) {
227 			if (di.di_ib[i] == 0)
228 				continue;
229 			ret |= dirindir(ino, di.di_ib[i], i, &filesize,
230 			    tape_size, nodump);
231 		}
232 		if (ret & HASDUMPEDFILE) {
233 			SETINO(ino, dumpinomap);
234 			*tape_size += blockest(&di);
235 			change = 1;
236 			continue;
237 		}
238 		if (nodump) {
239 			if (ret & HASSUBDIRS)
240 				change = 1;	/* subdirs inherit nodump */
241 			CLRINO(ino, dumpdirmap);
242 		} else if ((ret & HASSUBDIRS) == 0)
243 			if (!TSTINO(ino, dumpinomap)) {
244 				CLRINO(ino, dumpdirmap);
245 				change = 1;
246 			}
247 	}
248 	return (change);
249 }
250 
251 /*
252  * Read indirect blocks, and pass the data blocks to be searched
253  * as directories. Quit as soon as any entry is found that will
254  * require the directory to be dumped.
255  */
256 static int
257 dirindir(ufs1_ino_t ino, daddr_t blkno, int ind_level, long *filesize,
258          long *tape_size, int nodump)
259 {
260 	int ret = 0;
261 	int i;
262 	daddr_t	idblk[MAXNINDIR];
263 
264 	bread(fsbtodb(sblock, blkno), (char *)idblk, (int)sblock->fs_bsize);
265 	if (ind_level <= 0) {
266 		for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
267 			blkno = idblk[i];
268 			if (blkno != 0) {
269 				ret |= searchdir(ino, blkno, sblock->fs_bsize,
270 					*filesize, tape_size, nodump);
271 			}
272 			if (ret & HASDUMPEDFILE)
273 				*filesize = 0;
274 			else
275 				*filesize -= sblock->fs_bsize;
276 		}
277 		return (ret);
278 	}
279 	ind_level--;
280 	for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
281 		blkno = idblk[i];
282 		if (blkno != 0) {
283 			ret |= dirindir(ino, blkno, ind_level, filesize,
284 			    tape_size, nodump);
285 		}
286 	}
287 	return (ret);
288 }
289 
290 /*
291  * Scan a disk block containing directory information looking to see if
292  * any of the entries are on the dump list and to see if the directory
293  * contains any subdirectories.
294  */
295 static int
296 searchdir(ufs1_ino_t ino, daddr_t blkno, long size, long filesize,
297           long *tape_size, int nodump)
298 {
299 	struct direct *dp;
300 	struct ufs1_dinode *ip;
301 	long loc, ret = 0;
302 	char dblk[MAXBSIZE];
303 
304 	bread(fsbtodb(sblock, blkno), dblk, (int)size);
305 	if (filesize < size)
306 		size = filesize;
307 	for (loc = 0; loc < size; ) {
308 		dp = (struct direct *)(dblk + loc);
309 		if (dp->d_reclen == 0) {
310 			msg("corrupted directory, inumber %d\n", ino);
311 			break;
312 		}
313 		loc += dp->d_reclen;
314 		if (dp->d_ino == 0)
315 			continue;
316 		if (dp->d_name[0] == '.') {
317 			if (dp->d_name[1] == '\0')
318 				continue;
319 			if (dp->d_name[1] == '.' && dp->d_name[2] == '\0')
320 				continue;
321 		}
322 		if (nodump) {
323 			ip = getino(dp->d_ino);
324 			if (TSTINO(dp->d_ino, dumpinomap)) {
325 				CLRINO(dp->d_ino, dumpinomap);
326 				*tape_size -= blockest(ip);
327 			}
328 			/*
329 			 * Add back to dumpdirmap and remove from usedinomap
330 			 * to propagate nodump.
331 			 */
332 			if ((ip->di_mode & IFMT) == IFDIR) {
333 				SETINO(dp->d_ino, dumpdirmap);
334 				CLRINO(dp->d_ino, usedinomap);
335 				ret |= HASSUBDIRS;
336 			}
337 		} else {
338 			if (TSTINO(dp->d_ino, dumpinomap)) {
339 				ret |= HASDUMPEDFILE;
340 				if (ret & HASSUBDIRS)
341 					break;
342 			}
343 			if (TSTINO(dp->d_ino, dumpdirmap)) {
344 				ret |= HASSUBDIRS;
345 				if (ret & HASDUMPEDFILE)
346 					break;
347 			}
348 		}
349 	}
350 	return (ret);
351 }
352 
353 /*
354  * Dump passes 3 and 4.
355  *
356  * Dump the contents of an inode to tape.
357  */
358 void
359 dumpino(struct ufs1_dinode *dp, ufs1_ino_t ino)
360 {
361 	int ind_level, cnt;
362 	fsizeT size;
363 	char buf[TP_BSIZE];
364 
365 	if (newtape) {
366 		newtape = 0;
367 		dumpmap(dumpinomap, TS_BITS, ino);
368 	}
369 	CLRINO(ino, dumpinomap);
370 	spcl.c_dinode = *dp;
371 	spcl.c_type = TS_INODE;
372 	spcl.c_count = 0;
373 	switch (dp->di_mode & S_IFMT) {
374 
375 	case 0:
376 		/*
377 		 * Freed inode.
378 		 */
379 		return;
380 
381 	case S_IFLNK:
382 		/*
383 		 * Check for short symbolic link.
384 		 */
385 #ifdef FS_44INODEFMT
386 		if (dp->di_size > 0 &&
387 		    dp->di_size < (unsigned)sblock->fs_maxsymlinklen) {
388 			spcl.c_addr[0] = 1;
389 			spcl.c_count = 1;
390 			writeheader(ino);
391 			memmove(buf, dp->di_shortlink, (u_long)dp->di_size);
392 			buf[dp->di_size] = '\0';
393 			writerec(buf, 0);
394 			return;
395 		}
396 #endif
397 		/* fall through */
398 
399 	case S_IFDIR:
400 	case S_IFREG:
401 		if (dp->di_size > 0)
402 			break;
403 		/* fall through */
404 
405 	case S_IFIFO:
406 	case S_IFSOCK:
407 	case S_IFCHR:
408 	case S_IFBLK:
409 		writeheader(ino);
410 		return;
411 
412 	default:
413 		msg("Warning: undefined file type 0%o\n", dp->di_mode & IFMT);
414 		return;
415 	}
416 	if (dp->di_size > NDADDR * (unsigned)sblock->fs_bsize)
417 		cnt = NDADDR * sblock->fs_frag;
418 	else
419 		cnt = howmany(dp->di_size, sblock->fs_fsize);
420 	blksout(&dp->di_db[0], cnt, ino);
421 	if ((size = dp->di_size - NDADDR * sblock->fs_bsize) <= 0)
422 		return;
423 	for (ind_level = 0; ind_level < NIADDR; ind_level++) {
424 		dmpindir(ino, dp->di_ib[ind_level], ind_level, &size);
425 		if (size <= 0)
426 			return;
427 	}
428 }
429 
430 /*
431  * Read indirect blocks, and pass the data blocks to be dumped.
432  */
433 static void
434 dmpindir(ufs1_ino_t ino, daddr_t blk, int ind_level, fsizeT *size)
435 {
436 	int i, cnt;
437 	daddr_t idblk[MAXNINDIR];
438 
439 	if (blk != 0)
440 		bread(fsbtodb(sblock, blk), (char *)idblk, (int) sblock->fs_bsize);
441 	else
442 		memset(idblk, 0, (int)sblock->fs_bsize);
443 	if (ind_level <= 0) {
444 		if (*size < NINDIR(sblock) * sblock->fs_bsize)
445 			cnt = howmany(*size, sblock->fs_fsize);
446 		else
447 			cnt = NINDIR(sblock) * sblock->fs_frag;
448 		*size -= NINDIR(sblock) * sblock->fs_bsize;
449 		blksout(&idblk[0], cnt, ino);
450 		return;
451 	}
452 	ind_level--;
453 	for (i = 0; i < NINDIR(sblock); i++) {
454 		dmpindir(ino, idblk[i], ind_level, size);
455 		if (*size <= 0)
456 			return;
457 	}
458 }
459 
460 /*
461  * Collect up the data into tape record sized buffers and output them.
462  */
463 void
464 blksout(daddr_t *blkp, int frags, ufs1_ino_t ino)
465 {
466 	daddr_t *bp;
467 	int i, j, count, blks, tbperdb;
468 
469 	blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
470 	tbperdb = sblock->fs_bsize >> tp_bshift;
471 	for (i = 0; i < blks; i += TP_NINDIR) {
472 		if (i + TP_NINDIR > blks)
473 			count = blks;
474 		else
475 			count = i + TP_NINDIR;
476 		for (j = i; j < count; j++)
477 			if (blkp[j / tbperdb] != 0)
478 				spcl.c_addr[j - i] = 1;
479 			else
480 				spcl.c_addr[j - i] = 0;
481 		spcl.c_count = count - i;
482 		writeheader(ino);
483 		bp = &blkp[i / tbperdb];
484 		for (j = i; j < count; j += tbperdb, bp++)
485 			if (*bp != 0) {
486 				if (j + tbperdb <= count)
487 					dumpblock(*bp, (int)sblock->fs_bsize);
488 				else
489 					dumpblock(*bp, (count - j) * TP_BSIZE);
490 			}
491 		spcl.c_type = TS_ADDR;
492 	}
493 }
494 
495 /*
496  * Dump a map to the tape.
497  */
498 void
499 dumpmap(const char *map, int type, ufs1_ino_t ino)
500 {
501 	int i;
502 	const char *cp;
503 
504 	spcl.c_type = type;
505 	spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE);
506 	writeheader(ino);
507 	for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE)
508 		writerec(cp, 0);
509 }
510 
511 /*
512  * Write a header record to the dump tape.
513  */
514 void
515 writeheader(ufs1_ino_t ino)
516 {
517 	int32_t sum, cnt, *lp;
518 
519 	spcl.c_inumber = ino;
520 	spcl.c_magic = NFS_MAGIC;
521 	spcl.c_checksum = 0;
522 	lp = (int32_t *)&spcl;
523 	sum = 0;
524 	cnt = sizeof(union u_spcl) / (4 * sizeof(int32_t));
525 	while (--cnt >= 0) {
526 		sum += *lp++;
527 		sum += *lp++;
528 		sum += *lp++;
529 		sum += *lp++;
530 	}
531 	spcl.c_checksum = CHECKSUM - sum;
532 	writerec(&spcl, 1);
533 }
534 
535 struct ufs1_dinode *
536 getino(ufs1_ino_t inum)
537 {
538 	static daddr_t minino, maxino;
539 	static struct ufs1_dinode inoblock[MAXINOPB];
540 
541 	curino = inum;
542 	if (inum >= (unsigned)minino && inum < (unsigned)maxino)
543 		return (&inoblock[inum - minino]);
544 	bread(fsbtodb(sblock, ino_to_fsba(sblock, inum)), (char *)inoblock,
545 	    (int)sblock->fs_bsize);
546 	minino = inum - (inum % INOPB(sblock));
547 	maxino = minino + INOPB(sblock);
548 	return (&inoblock[inum - minino]);
549 }
550 
551 /*
552  * Read a chunk of data from the disk.
553  * Try to recover from hard errors by reading in sector sized pieces.
554  * Error recovery is attempted at most BREADEMAX times before seeking
555  * consent from the operator to continue.
556  */
557 int	breaderrors = 0;
558 #define	BREADEMAX 32
559 
560 void
561 bread(daddr_t blkno, char *buf, int size)
562 {
563 	int cnt, i;
564 
565 loop:
566 	cnt = cread(diskfd, buf, size, ((off_t)blkno << dev_bshift));
567 	if (cnt == size)
568 		return;
569 	if (blkno + (size / dev_bsize) > fsbtodb(sblock, sblock->fs_size)) {
570 		/*
571 		 * Trying to read the final fragment.
572 		 *
573 		 * NB - dump only works in TP_BSIZE blocks, hence
574 		 * rounds `dev_bsize' fragments up to TP_BSIZE pieces.
575 		 * It should be smarter about not actually trying to
576 		 * read more than it can get, but for the time being
577 		 * we punt and scale back the read only when it gets
578 		 * us into trouble. (mkm 9/25/83)
579 		 */
580 		size -= dev_bsize;
581 		goto loop;
582 	}
583 	if (cnt == -1)
584 		msg("read error from %s: %s: [block %d]: count=%d\n",
585 			disk, strerror(errno), blkno, size);
586 	else
587 		msg("short read error from %s: [block %d]: count=%d, got=%d\n",
588 			disk, blkno, size, cnt);
589 	if (++breaderrors > BREADEMAX) {
590 		msg("More than %d block read errors from %s\n",
591 			BREADEMAX, disk);
592 		broadcast("DUMP IS AILING!\n");
593 		msg("This is an unrecoverable error.\n");
594 		if (!query("Do you want to attempt to continue?")){
595 			dumpabort(0);
596 			/*NOTREACHED*/
597 		} else
598 			breaderrors = 0;
599 	}
600 	/*
601 	 * Zero buffer, then try to read each sector of buffer separately,
602 	 * and bypass the cache.
603 	 */
604 	memset(buf, 0, size);
605 	for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
606 		if ((cnt = pread(diskfd, buf, (int)dev_bsize,
607 		    ((off_t)blkno << dev_bshift))) == dev_bsize)
608 			continue;
609 		if (cnt == -1) {
610 			msg("read error from %s: %s: [sector %d]: count=%ld\n",
611 				disk, strerror(errno), blkno, dev_bsize);
612 			continue;
613 		}
614 		msg("short read error from %s: [sector %d]: count=%ld, got=%d\n",
615 			disk, blkno, dev_bsize, cnt);
616 	}
617 }
618