xref: /original-bsd/sbin/dump/traverse.c (revision 0842ddeb)
1 /*-
2  * Copyright (c) 1980, 1988, 1991, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * %sccs.include.redist.c%
6  */
7 
8 #ifndef lint
9 static char sccsid[] = "@(#)traverse.c	8.6 (Berkeley) 05/02/95";
10 #endif /* not lint */
11 
12 #include <sys/param.h>
13 #include <sys/time.h>
14 #include <sys/stat.h>
15 #ifdef sunos
16 #include <sys/vnode.h>
17 
18 #include <ufs/fs.h>
19 #include <ufs/fsdir.h>
20 #include <ufs/inode.h>
21 #else
22 #include <ufs/ufs/dir.h>
23 #include <ufs/ufs/dinode.h>
24 #include <ufs/ffs/fs.h>
25 #endif
26 
27 #include <protocols/dumprestore.h>
28 
29 #include <ctype.h>
30 #include <stdio.h>
31 #ifdef __STDC__
32 #include <string.h>
33 #include <unistd.h>
34 #endif
35 
36 #include "dump.h"
37 
38 #define	HASDUMPEDFILE	0x1
39 #define	HASSUBDIRS	0x2
40 
41 #ifdef	FS_44INODEFMT
42 typedef	quad_t fsizeT;
43 #else
44 typedef	long fsizeT;
45 #endif
46 
47 static	int dirindir __P((ino_t ino, daddr_t blkno, int level, long *size));
48 static	void dmpindir __P((ino_t ino, daddr_t blk, int level, fsizeT *size));
49 static	int searchdir __P((ino_t ino, daddr_t blkno, long size, long filesize));
50 
51 /*
52  * This is an estimation of the number of TP_BSIZE blocks in the file.
53  * It estimates the number of blocks in files with holes by assuming
54  * that all of the blocks accounted for by di_blocks are data blocks
55  * (when some of the blocks are usually used for indirect pointers);
56  * hence the estimate may be high.
57  */
58 long
59 blockest(dp)
60 	register struct dinode *dp;
61 {
62 	long blkest, sizeest;
63 
64 	/*
65 	 * dp->di_size is the size of the file in bytes.
66 	 * dp->di_blocks stores the number of sectors actually in the file.
67 	 * If there are more sectors than the size would indicate, this just
68 	 *	means that there are indirect blocks in the file or unused
69 	 *	sectors in the last file block; we can safely ignore these
70 	 *	(blkest = sizeest below).
71 	 * If the file is bigger than the number of sectors would indicate,
72 	 *	then the file has holes in it.	In this case we must use the
73 	 *	block count to estimate the number of data blocks used, but
74 	 *	we use the actual size for estimating the number of indirect
75 	 *	dump blocks (sizeest vs. blkest in the indirect block
76 	 *	calculation).
77 	 */
78 	blkest = howmany(dbtob(dp->di_blocks), TP_BSIZE);
79 	sizeest = howmany(dp->di_size, TP_BSIZE);
80 	if (blkest > sizeest)
81 		blkest = sizeest;
82 	if (dp->di_size > sblock->fs_bsize * NDADDR) {
83 		/* calculate the number of indirect blocks on the dump tape */
84 		blkest +=
85 			howmany(sizeest - NDADDR * sblock->fs_bsize / TP_BSIZE,
86 			TP_NINDIR);
87 	}
88 	return (blkest + 1);
89 }
90 
91 /* Auxiliary macro to pick up files changed since previous dump. */
92 #define	CHANGEDSINCE(dp, t) \
93 	((dp)->di_mtime >= (t) || (dp)->di_ctime >= (t))
94 
95 /* The WANTTODUMP macro decides whether a file should be dumped. */
96 #ifdef UF_NODUMP
97 #define	WANTTODUMP(dp) \
98 	(CHANGEDSINCE(dp, spcl.c_ddate) && \
99 	 (nonodump || ((dp)->di_flags & UF_NODUMP) != UF_NODUMP))
100 #else
101 #define	WANTTODUMP(dp) CHANGEDSINCE(dp, spcl.c_ddate)
102 #endif
103 
104 /*
105  * Dump pass 1.
106  *
107  * Walk the inode list for a filesystem to find all allocated inodes
108  * that have been modified since the previous dump time. Also, find all
109  * the directories in the filesystem.
110  */
111 int
112 mapfiles(maxino, tapesize)
113 	ino_t maxino;
114 	long *tapesize;
115 {
116 	register int mode;
117 	register ino_t ino;
118 	register struct dinode *dp;
119 	int anydirskipped = 0;
120 
121 	for (ino = ROOTINO; ino < maxino; ino++) {
122 		dp = getino(ino);
123 		if ((mode = (dp->di_mode & IFMT)) == 0)
124 			continue;
125 		SETINO(ino, usedinomap);
126 		if (mode == IFDIR)
127 			SETINO(ino, dumpdirmap);
128 		if (WANTTODUMP(dp)) {
129 			SETINO(ino, dumpinomap);
130 			if (mode != IFREG && mode != IFDIR && mode != IFLNK)
131 				*tapesize += 1;
132 			else
133 				*tapesize += blockest(dp);
134 			continue;
135 		}
136 		if (mode == IFDIR)
137 			anydirskipped = 1;
138 	}
139 	/*
140 	 * Restore gets very upset if the root is not dumped,
141 	 * so ensure that it always is dumped.
142 	 */
143 	SETINO(ROOTINO, dumpinomap);
144 	return (anydirskipped);
145 }
146 
147 /*
148  * Dump pass 2.
149  *
150  * Scan each directory on the filesystem to see if it has any modified
151  * files in it. If it does, and has not already been added to the dump
152  * list (because it was itself modified), then add it. If a directory
153  * has not been modified itself, contains no modified files and has no
154  * subdirectories, then it can be deleted from the dump list and from
155  * the list of directories. By deleting it from the list of directories,
156  * its parent may now qualify for the same treatment on this or a later
157  * pass using this algorithm.
158  */
159 int
160 mapdirs(maxino, tapesize)
161 	ino_t maxino;
162 	long *tapesize;
163 {
164 	register struct	dinode *dp;
165 	register int i, isdir;
166 	register char *map;
167 	register ino_t ino;
168 	long filesize;
169 	int ret, change = 0;
170 
171 	isdir = 0;		/* XXX just to get gcc to shut up */
172 	for (map = dumpdirmap, ino = 1; ino < maxino; ino++) {
173 		if (((ino - 1) % NBBY) == 0)	/* map is offset by 1 */
174 			isdir = *map++;
175 		else
176 			isdir >>= 1;
177 		if ((isdir & 1) == 0 || TSTINO(ino, dumpinomap))
178 			continue;
179 		dp = getino(ino);
180 		filesize = dp->di_size;
181 		for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) {
182 			if (dp->di_db[i] != 0)
183 				ret |= searchdir(ino, dp->di_db[i],
184 					(long)dblksize(sblock, dp, i),
185 					filesize);
186 			if (ret & HASDUMPEDFILE)
187 				filesize = 0;
188 			else
189 				filesize -= sblock->fs_bsize;
190 		}
191 		for (i = 0; filesize > 0 && i < NIADDR; i++) {
192 			if (dp->di_ib[i] == 0)
193 				continue;
194 			ret |= dirindir(ino, dp->di_ib[i], i, &filesize);
195 		}
196 		if (ret & HASDUMPEDFILE) {
197 			SETINO(ino, dumpinomap);
198 			*tapesize += blockest(dp);
199 			change = 1;
200 			continue;
201 		}
202 		if ((ret & HASSUBDIRS) == 0) {
203 			if (!TSTINO(ino, dumpinomap)) {
204 				CLRINO(ino, dumpdirmap);
205 				change = 1;
206 			}
207 		}
208 	}
209 	return (change);
210 }
211 
212 /*
213  * Read indirect blocks, and pass the data blocks to be searched
214  * as directories. Quit as soon as any entry is found that will
215  * require the directory to be dumped.
216  */
217 static int
218 dirindir(ino, blkno, ind_level, filesize)
219 	ino_t ino;
220 	daddr_t blkno;
221 	int ind_level;
222 	long *filesize;
223 {
224 	int ret = 0;
225 	register int i;
226 	daddr_t	idblk[MAXNINDIR];
227 
228 	bread(fsbtodb(sblock, blkno), (char *)idblk, (int)sblock->fs_bsize);
229 	if (ind_level <= 0) {
230 		for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
231 			blkno = idblk[i];
232 			if (blkno != 0)
233 				ret |= searchdir(ino, blkno, sblock->fs_bsize,
234 					*filesize);
235 			if (ret & HASDUMPEDFILE)
236 				*filesize = 0;
237 			else
238 				*filesize -= sblock->fs_bsize;
239 		}
240 		return (ret);
241 	}
242 	ind_level--;
243 	for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
244 		blkno = idblk[i];
245 		if (blkno != 0)
246 			ret |= dirindir(ino, blkno, ind_level, filesize);
247 	}
248 	return (ret);
249 }
250 
251 /*
252  * Scan a disk block containing directory information looking to see if
253  * any of the entries are on the dump list and to see if the directory
254  * contains any subdirectories.
255  */
256 static int
257 searchdir(ino, blkno, size, filesize)
258 	ino_t ino;
259 	daddr_t blkno;
260 	register long size;
261 	long filesize;
262 {
263 	register struct direct *dp;
264 	register long loc, ret = 0;
265 	char dblk[MAXBSIZE];
266 
267 	bread(fsbtodb(sblock, blkno), dblk, (int)size);
268 	if (filesize < size)
269 		size = filesize;
270 	for (loc = 0; loc < size; ) {
271 		dp = (struct direct *)(dblk + loc);
272 		if (dp->d_reclen == 0) {
273 			msg("corrupted directory, inumber %d\n", ino);
274 			break;
275 		}
276 		loc += dp->d_reclen;
277 		if (dp->d_ino == 0)
278 			continue;
279 		if (dp->d_name[0] == '.') {
280 			if (dp->d_name[1] == '\0')
281 				continue;
282 			if (dp->d_name[1] == '.' && dp->d_name[2] == '\0')
283 				continue;
284 		}
285 		if (TSTINO(dp->d_ino, dumpinomap)) {
286 			ret |= HASDUMPEDFILE;
287 			if (ret & HASSUBDIRS)
288 				break;
289 		}
290 		if (TSTINO(dp->d_ino, dumpdirmap)) {
291 			ret |= HASSUBDIRS;
292 			if (ret & HASDUMPEDFILE)
293 				break;
294 		}
295 	}
296 	return (ret);
297 }
298 
299 /*
300  * Dump passes 3 and 4.
301  *
302  * Dump the contents of an inode to tape.
303  */
304 void
305 dumpino(dp, ino)
306 	register struct dinode *dp;
307 	ino_t ino;
308 {
309 	int ind_level, cnt;
310 	fsizeT size;
311 	char buf[TP_BSIZE];
312 
313 	if (newtape) {
314 		newtape = 0;
315 		dumpmap(dumpinomap, TS_BITS, ino);
316 	}
317 	CLRINO(ino, dumpinomap);
318 	spcl.c_dinode = *dp;
319 	spcl.c_type = TS_INODE;
320 	spcl.c_count = 0;
321 	switch (dp->di_mode & S_IFMT) {
322 
323 	case 0:
324 		/*
325 		 * Freed inode.
326 		 */
327 		return;
328 
329 	case S_IFLNK:
330 		/*
331 		 * Check for short symbolic link.
332 		 */
333 #ifdef FS_44INODEFMT
334 		if (dp->di_size > 0 &&
335 		    dp->di_size < sblock->fs_maxsymlinklen) {
336 			spcl.c_addr[0] = 1;
337 			spcl.c_count = 1;
338 			writeheader(ino);
339 			memmove(buf, dp->di_shortlink, (u_long)dp->di_size);
340 			buf[dp->di_size] = '\0';
341 			writerec(buf, 0);
342 			return;
343 		}
344 #endif
345 		/* fall through */
346 
347 	case S_IFDIR:
348 	case S_IFREG:
349 		if (dp->di_size > 0)
350 			break;
351 		/* fall through */
352 
353 	case S_IFIFO:
354 	case S_IFSOCK:
355 	case S_IFCHR:
356 	case S_IFBLK:
357 		writeheader(ino);
358 		return;
359 
360 	default:
361 		msg("Warning: undefined file type 0%o\n", dp->di_mode & IFMT);
362 		return;
363 	}
364 	if (dp->di_size > NDADDR * sblock->fs_bsize)
365 		cnt = NDADDR * sblock->fs_frag;
366 	else
367 		cnt = howmany(dp->di_size, sblock->fs_fsize);
368 	blksout(&dp->di_db[0], cnt, ino);
369 	if ((size = dp->di_size - NDADDR * sblock->fs_bsize) <= 0)
370 		return;
371 	for (ind_level = 0; ind_level < NIADDR; ind_level++) {
372 		dmpindir(ino, dp->di_ib[ind_level], ind_level, &size);
373 		if (size <= 0)
374 			return;
375 	}
376 }
377 
378 /*
379  * Read indirect blocks, and pass the data blocks to be dumped.
380  */
381 static void
382 dmpindir(ino, blk, ind_level, size)
383 	ino_t ino;
384 	daddr_t blk;
385 	int ind_level;
386 	fsizeT *size;
387 {
388 	int i, cnt;
389 	daddr_t idblk[MAXNINDIR];
390 
391 	if (blk != 0)
392 		bread(fsbtodb(sblock, blk), (char *)idblk, (int) sblock->fs_bsize);
393 	else
394 		memset(idblk, 0, (int)sblock->fs_bsize);
395 	if (ind_level <= 0) {
396 		if (*size < NINDIR(sblock) * sblock->fs_bsize)
397 			cnt = howmany(*size, sblock->fs_fsize);
398 		else
399 			cnt = NINDIR(sblock) * sblock->fs_frag;
400 		*size -= NINDIR(sblock) * sblock->fs_bsize;
401 		blksout(&idblk[0], cnt, ino);
402 		return;
403 	}
404 	ind_level--;
405 	for (i = 0; i < NINDIR(sblock); i++) {
406 		dmpindir(ino, idblk[i], ind_level, size);
407 		if (*size <= 0)
408 			return;
409 	}
410 }
411 
412 /*
413  * Collect up the data into tape record sized buffers and output them.
414  */
415 void
416 blksout(blkp, frags, ino)
417 	daddr_t *blkp;
418 	int frags;
419 	ino_t ino;
420 {
421 	register daddr_t *bp;
422 	int i, j, count, blks, tbperdb;
423 
424 	blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
425 	tbperdb = sblock->fs_bsize >> tp_bshift;
426 	for (i = 0; i < blks; i += TP_NINDIR) {
427 		if (i + TP_NINDIR > blks)
428 			count = blks;
429 		else
430 			count = i + TP_NINDIR;
431 		for (j = i; j < count; j++)
432 			if (blkp[j / tbperdb] != 0)
433 				spcl.c_addr[j - i] = 1;
434 			else
435 				spcl.c_addr[j - i] = 0;
436 		spcl.c_count = count - i;
437 		writeheader(ino);
438 		bp = &blkp[i / tbperdb];
439 		for (j = i; j < count; j += tbperdb, bp++)
440 			if (*bp != 0)
441 				if (j + tbperdb <= count)
442 					dumpblock(*bp, (int)sblock->fs_bsize);
443 				else
444 					dumpblock(*bp, (count - j) * TP_BSIZE);
445 		spcl.c_type = TS_ADDR;
446 	}
447 }
448 
449 /*
450  * Dump a map to the tape.
451  */
452 void
453 dumpmap(map, type, ino)
454 	char *map;
455 	int type;
456 	ino_t ino;
457 {
458 	register int i;
459 	char *cp;
460 
461 	spcl.c_type = type;
462 	spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE);
463 	writeheader(ino);
464 	for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE)
465 		writerec(cp, 0);
466 }
467 
468 /*
469  * Write a header record to the dump tape.
470  */
471 void
472 writeheader(ino)
473 	ino_t ino;
474 {
475 	register long sum, cnt, *lp;
476 
477 	spcl.c_inumber = ino;
478 	spcl.c_magic = NFS_MAGIC;
479 	spcl.c_checksum = 0;
480 	lp = (long *)&spcl;
481 	sum = 0;
482 	cnt = sizeof(union u_spcl) / (4 * sizeof(long));
483 	while (--cnt >= 0) {
484 		sum += *lp++;
485 		sum += *lp++;
486 		sum += *lp++;
487 		sum += *lp++;
488 	}
489 	spcl.c_checksum = CHECKSUM - sum;
490 	writerec((char *)&spcl, 1);
491 }
492 
493 struct dinode *
494 getino(inum)
495 	ino_t inum;
496 {
497 	static daddr_t minino, maxino;
498 	static struct dinode inoblock[MAXINOPB];
499 
500 	curino = inum;
501 	if (inum >= minino && inum < maxino)
502 		return (&inoblock[inum - minino]);
503 	bread(fsbtodb(sblock, ino_to_fsba(sblock, inum)), (char *)inoblock,
504 	    (int)sblock->fs_bsize);
505 	minino = inum - (inum % INOPB(sblock));
506 	maxino = minino + INOPB(sblock);
507 	return (&inoblock[inum - minino]);
508 }
509 
510 /*
511  * Read a chunk of data from the disk.
512  * Try to recover from hard errors by reading in sector sized pieces.
513  * Error recovery is attempted at most BREADEMAX times before seeking
514  * consent from the operator to continue.
515  */
516 int	breaderrors = 0;
517 #define	BREADEMAX 32
518 
519 void
520 bread(blkno, buf, size)
521 	daddr_t blkno;
522 	char *buf;
523 	int size;
524 {
525 	int cnt, i;
526 	extern int errno;
527 
528 loop:
529 	if ((int)lseek(diskfd, ((off_t)blkno << dev_bshift), 0) < 0)
530 		msg("bread: lseek fails\n");
531 	if ((cnt = read(diskfd, buf, size)) == size)
532 		return;
533 	if (blkno + (size / dev_bsize) > fsbtodb(sblock, sblock->fs_size)) {
534 		/*
535 		 * Trying to read the final fragment.
536 		 *
537 		 * NB - dump only works in TP_BSIZE blocks, hence
538 		 * rounds `dev_bsize' fragments up to TP_BSIZE pieces.
539 		 * It should be smarter about not actually trying to
540 		 * read more than it can get, but for the time being
541 		 * we punt and scale back the read only when it gets
542 		 * us into trouble. (mkm 9/25/83)
543 		 */
544 		size -= dev_bsize;
545 		goto loop;
546 	}
547 	if (cnt == -1)
548 		msg("read error from %s: %s: [block %d]: count=%d\n",
549 			disk, strerror(errno), blkno, size);
550 	else
551 		msg("short read error from %s: [block %d]: count=%d, got=%d\n",
552 			disk, blkno, size, cnt);
553 	if (++breaderrors > BREADEMAX) {
554 		msg("More than %d block read errors from %d\n",
555 			BREADEMAX, disk);
556 		broadcast("DUMP IS AILING!\n");
557 		msg("This is an unrecoverable error.\n");
558 		if (!query("Do you want to attempt to continue?")){
559 			dumpabort(0);
560 			/*NOTREACHED*/
561 		} else
562 			breaderrors = 0;
563 	}
564 	/*
565 	 * Zero buffer, then try to read each sector of buffer separately.
566 	 */
567 	memset(buf, 0, size);
568 	for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
569 		if ((int)lseek(diskfd, ((off_t)blkno << dev_bshift), 0) < 0)
570 			msg("bread: lseek2 fails!\n");
571 		if ((cnt = read(diskfd, buf, (int)dev_bsize)) == dev_bsize)
572 			continue;
573 		if (cnt == -1) {
574 			msg("read error from %s: %s: [sector %d]: count=%d\n",
575 				disk, strerror(errno), blkno, dev_bsize);
576 			continue;
577 		}
578 		msg("short read error from %s: [sector %d]: count=%d, got=%d\n",
579 			disk, blkno, dev_bsize, cnt);
580 	}
581 }
582