xref: /freebsd/sbin/dump/traverse.c (revision f0adf7f5cdd241db2f2c817683191a6ef64a4e95)
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  * 4. 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 
30 #ifndef lint
31 #if 0
32 static char sccsid[] = "@(#)traverse.c	8.7 (Berkeley) 6/15/95";
33 #endif
34 static const char rcsid[] =
35   "$FreeBSD$";
36 #endif /* not lint */
37 
38 #include <sys/param.h>
39 #include <sys/stat.h>
40 
41 #include <ufs/ufs/dir.h>
42 #include <ufs/ufs/dinode.h>
43 #include <ufs/ffs/fs.h>
44 
45 #include <protocols/dumprestore.h>
46 
47 #include <ctype.h>
48 #include <errno.h>
49 #include <inttypes.h>
50 #include <limits.h>
51 #include <stdio.h>
52 #include <stdlib.h>
53 #include <string.h>
54 #include <timeconv.h>
55 #include <unistd.h>
56 
57 #include "dump.h"
58 
59 union dinode {
60 	struct ufs1_dinode dp1;
61 	struct ufs2_dinode dp2;
62 };
63 #define	DIP(dp, field) \
64 	((sblock->fs_magic == FS_UFS1_MAGIC) ? \
65 	(dp)->dp1.field : (dp)->dp2.field)
66 
67 #define	HASDUMPEDFILE	0x1
68 #define	HASSUBDIRS	0x2
69 
70 static	int dirindir(ino_t ino, ufs2_daddr_t blkno, int level, long *size,
71     long *tapesize, int nodump);
72 static	void dmpindir(ino_t ino, ufs2_daddr_t blk, int level, off_t *size);
73 static	int searchdir(ino_t ino, ufs2_daddr_t blkno, long size, long filesize,
74     long *tapesize, int nodump);
75 static	long blockest(union dinode *dp);
76 
77 /*
78  * This is an estimation of the number of TP_BSIZE blocks in the file.
79  * It estimates the number of blocks in files with holes by assuming
80  * that all of the blocks accounted for by di_blocks are data blocks
81  * (when some of the blocks are usually used for indirect pointers);
82  * hence the estimate may be high.
83  */
84 static long
85 blockest(union dinode *dp)
86 {
87 	long blkest, sizeest;
88 
89 	/*
90 	 * dp->di_size is the size of the file in bytes.
91 	 * dp->di_blocks stores the number of sectors actually in the file.
92 	 * If there are more sectors than the size would indicate, this just
93 	 *	means that there are indirect blocks in the file or unused
94 	 *	sectors in the last file block; we can safely ignore these
95 	 *	(blkest = sizeest below).
96 	 * If the file is bigger than the number of sectors would indicate,
97 	 *	then the file has holes in it.	In this case we must use the
98 	 *	block count to estimate the number of data blocks used, but
99 	 *	we use the actual size for estimating the number of indirect
100 	 *	dump blocks (sizeest vs. blkest in the indirect block
101 	 *	calculation).
102 	 */
103 	if ((DIP(dp, di_flags) & SF_SNAPSHOT) != 0)
104 		return (1);
105 	blkest = howmany(dbtob(DIP(dp, di_blocks)), TP_BSIZE);
106 	sizeest = howmany(DIP(dp, di_size), TP_BSIZE);
107 	if (blkest > sizeest)
108 		blkest = sizeest;
109 	if (DIP(dp, di_size) > sblock->fs_bsize * NDADDR) {
110 		/* calculate the number of indirect blocks on the dump tape */
111 		blkest +=
112 			howmany(sizeest - NDADDR * sblock->fs_bsize / TP_BSIZE,
113 			TP_NINDIR);
114 	}
115 	return (blkest + 1);
116 }
117 
118 /* Auxiliary macro to pick up files changed since previous dump. */
119 #define	CHANGEDSINCE(dp, t) \
120 	(DIP(dp, di_mtime) >= (t) || DIP(dp, di_ctime) >= (t))
121 
122 /* The WANTTODUMP macro decides whether a file should be dumped. */
123 #ifdef UF_NODUMP
124 #define	WANTTODUMP(dp) \
125 	(CHANGEDSINCE(dp, spcl.c_ddate) && \
126 	 (nonodump || (DIP(dp, di_flags) & UF_NODUMP) != UF_NODUMP))
127 #else
128 #define	WANTTODUMP(dp) CHANGEDSINCE(dp, spcl.c_ddate)
129 #endif
130 
131 /*
132  * Dump pass 1.
133  *
134  * Walk the inode list for a file system to find all allocated inodes
135  * that have been modified since the previous dump time. Also, find all
136  * the directories in the file system.
137  */
138 int
139 mapfiles(ino_t maxino, long *tapesize)
140 {
141 	int i, cg, mode, inosused;
142 	int anydirskipped = 0;
143 	union dinode *dp;
144 	struct cg *cgp;
145 	ino_t ino;
146 	char *cp;
147 
148 	if ((cgp = malloc(sblock->fs_cgsize)) == NULL)
149 		quit("mapfiles: cannot allocate memory.\n");
150 	for (cg = 0; cg < sblock->fs_ncg; cg++) {
151 		ino = cg * sblock->fs_ipg;
152 		bread(fsbtodb(sblock, cgtod(sblock, cg)), (char *)cgp,
153 		    sblock->fs_cgsize);
154 		if (sblock->fs_magic == FS_UFS2_MAGIC)
155 			inosused = cgp->cg_initediblk;
156 		else
157 			inosused = sblock->fs_ipg;
158 		/*
159 		 * If we are using soft updates, then we can trust the
160 		 * cylinder group inode allocation maps to tell us which
161 		 * inodes are allocated. We will scan the used inode map
162 		 * to find the inodes that are really in use, and then
163 		 * read only those inodes in from disk.
164 		 */
165 		if (sblock->fs_flags & FS_DOSOFTDEP) {
166 			if (!cg_chkmagic(cgp))
167 				quit("mapfiles: cg %d: bad magic number\n", cg);
168 			cp = &cg_inosused(cgp)[(inosused - 1) / CHAR_BIT];
169 			for ( ; inosused > 0; inosused -= CHAR_BIT, cp--) {
170 				if (*cp == 0)
171 					continue;
172 				for (i = 1 << (CHAR_BIT - 1); i > 0; i >>= 1) {
173 					if (*cp & i)
174 						break;
175 					inosused--;
176 				}
177 				break;
178 			}
179 			if (inosused <= 0)
180 				continue;
181 		}
182 		for (i = 0; i < inosused; i++, ino++) {
183 			if (ino < ROOTINO ||
184 			    (dp = getino(ino, &mode)) == NULL ||
185 			    (mode & IFMT) == 0)
186 				continue;
187 			/*
188 			 * Everything must go in usedinomap so that a check
189 			 * for "in dumpdirmap but not in usedinomap" to detect
190 			 * dirs with nodump set has a chance of succeeding
191 			 * (this is used in mapdirs()).
192 			 */
193 			SETINO(ino, usedinomap);
194 			if (mode == IFDIR)
195 				SETINO(ino, dumpdirmap);
196 			if (WANTTODUMP(dp)) {
197 				SETINO(ino, dumpinomap);
198 				if (mode != IFREG &&
199 				    mode != IFDIR &&
200 				    mode != IFLNK)
201 					*tapesize += 1;
202 				else
203 					*tapesize += blockest(dp);
204 				continue;
205 			}
206 			if (mode == IFDIR) {
207 				if (!nonodump &&
208 				    (DIP(dp, di_flags) & UF_NODUMP))
209 					CLRINO(ino, usedinomap);
210 				anydirskipped = 1;
211 			}
212 		}
213 	}
214 	/*
215 	 * Restore gets very upset if the root is not dumped,
216 	 * so ensure that it always is dumped.
217 	 */
218 	SETINO(ROOTINO, dumpinomap);
219 	return (anydirskipped);
220 }
221 
222 /*
223  * Dump pass 2.
224  *
225  * Scan each directory on the file system to see if it has any modified
226  * files in it. If it does, and has not already been added to the dump
227  * list (because it was itself modified), then add it. If a directory
228  * has not been modified itself, contains no modified files and has no
229  * subdirectories, then it can be deleted from the dump list and from
230  * the list of directories. By deleting it from the list of directories,
231  * its parent may now qualify for the same treatment on this or a later
232  * pass using this algorithm.
233  */
234 int
235 mapdirs(ino_t maxino, long *tapesize)
236 {
237 	union dinode *dp;
238 	int i, isdir, nodump;
239 	char *map;
240 	ino_t ino;
241 	union dinode di;
242 	long filesize;
243 	int ret, change = 0;
244 
245 	isdir = 0;		/* XXX just to get gcc to shut up */
246 	for (map = dumpdirmap, ino = 1; ino < maxino; ino++) {
247 		if (((ino - 1) % CHAR_BIT) == 0)	/* map is offset by 1 */
248 			isdir = *map++;
249 		else
250 			isdir >>= 1;
251 		/*
252 		 * If a directory has been removed from usedinomap, it
253 		 * either has the nodump flag set, or has inherited
254 		 * it.  Although a directory can't be in dumpinomap if
255 		 * it isn't in usedinomap, we have to go through it to
256 		 * propagate the nodump flag.
257 		 */
258 		nodump = !nonodump && (TSTINO(ino, usedinomap) == 0);
259 		if ((isdir & 1) == 0 || (TSTINO(ino, dumpinomap) && !nodump))
260 			continue;
261 		dp = getino(ino, &i);
262 		/*
263 		 * inode buf may change in searchdir().
264 		 */
265 		if (sblock->fs_magic == FS_UFS1_MAGIC)
266 			di.dp1 = dp->dp1;
267 		else
268 			di.dp2 = dp->dp2;
269 		filesize = DIP(&di, di_size);
270 		for (ret = 0, i = 0; filesize > 0 && i < NDADDR; i++) {
271 			if (DIP(&di, di_db[i]) != 0)
272 				ret |= searchdir(ino, DIP(&di, di_db[i]),
273 				    (long)sblksize(sblock, DIP(&di, di_size),
274 				    i), filesize, tapesize, nodump);
275 			if (ret & HASDUMPEDFILE)
276 				filesize = 0;
277 			else
278 				filesize -= sblock->fs_bsize;
279 		}
280 		for (i = 0; filesize > 0 && i < NIADDR; i++) {
281 			if (DIP(&di, di_ib[i]) == 0)
282 				continue;
283 			ret |= dirindir(ino, DIP(&di, di_ib[i]), i, &filesize,
284 			    tapesize, nodump);
285 		}
286 		if (ret & HASDUMPEDFILE) {
287 			SETINO(ino, dumpinomap);
288 			*tapesize += blockest(&di);
289 			change = 1;
290 			continue;
291 		}
292 		if (nodump) {
293 			if (ret & HASSUBDIRS)
294 				change = 1;	/* subdirs inherit nodump */
295 			CLRINO(ino, dumpdirmap);
296 		} else if ((ret & HASSUBDIRS) == 0)
297 			if (!TSTINO(ino, dumpinomap)) {
298 				CLRINO(ino, dumpdirmap);
299 				change = 1;
300 			}
301 	}
302 	return (change);
303 }
304 
305 /*
306  * Read indirect blocks, and pass the data blocks to be searched
307  * as directories. Quit as soon as any entry is found that will
308  * require the directory to be dumped.
309  */
310 static int
311 dirindir(
312 	ino_t ino,
313 	ufs2_daddr_t blkno,
314 	int ind_level,
315 	long *filesize,
316 	long *tapesize,
317 	int nodump)
318 {
319 	union {
320 		ufs1_daddr_t ufs1[MAXBSIZE / sizeof(ufs1_daddr_t)];
321 		ufs2_daddr_t ufs2[MAXBSIZE / sizeof(ufs2_daddr_t)];
322 	} idblk;
323 	int ret = 0;
324 	int i;
325 
326 	bread(fsbtodb(sblock, blkno), (char *)&idblk, (int)sblock->fs_bsize);
327 	if (ind_level <= 0) {
328 		for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
329 			if (sblock->fs_magic == FS_UFS1_MAGIC)
330 				blkno = idblk.ufs1[i];
331 			else
332 				blkno = idblk.ufs2[i];
333 			if (blkno != 0)
334 				ret |= searchdir(ino, blkno, sblock->fs_bsize,
335 					*filesize, tapesize, nodump);
336 			if (ret & HASDUMPEDFILE)
337 				*filesize = 0;
338 			else
339 				*filesize -= sblock->fs_bsize;
340 		}
341 		return (ret);
342 	}
343 	ind_level--;
344 	for (i = 0; *filesize > 0 && i < NINDIR(sblock); i++) {
345 		if (sblock->fs_magic == FS_UFS1_MAGIC)
346 			blkno = idblk.ufs1[i];
347 		else
348 			blkno = idblk.ufs2[i];
349 		if (blkno != 0)
350 			ret |= dirindir(ino, blkno, ind_level, filesize,
351 			    tapesize, nodump);
352 	}
353 	return (ret);
354 }
355 
356 /*
357  * Scan a disk block containing directory information looking to see if
358  * any of the entries are on the dump list and to see if the directory
359  * contains any subdirectories.
360  */
361 static int
362 searchdir(
363 	ino_t ino,
364 	ufs2_daddr_t blkno,
365 	long size,
366 	long filesize,
367 	long *tapesize,
368 	int nodump)
369 {
370 	int mode;
371 	struct direct *dp;
372 	union dinode *ip;
373 	long loc, ret = 0;
374 	static caddr_t dblk;
375 
376 	if (dblk == NULL && (dblk = malloc(sblock->fs_bsize)) == NULL)
377 		quit("searchdir: cannot allocate indirect memory.\n");
378 	bread(fsbtodb(sblock, blkno), dblk, (int)size);
379 	if (filesize < size)
380 		size = filesize;
381 	for (loc = 0; loc < size; ) {
382 		dp = (struct direct *)(dblk + loc);
383 		if (dp->d_reclen == 0) {
384 			msg("corrupted directory, inumber %d\n", ino);
385 			break;
386 		}
387 		loc += dp->d_reclen;
388 		if (dp->d_ino == 0)
389 			continue;
390 		if (dp->d_name[0] == '.') {
391 			if (dp->d_name[1] == '\0')
392 				continue;
393 			if (dp->d_name[1] == '.' && dp->d_name[2] == '\0')
394 				continue;
395 		}
396 		if (nodump) {
397 			ip = getino(dp->d_ino, &mode);
398 			if (TSTINO(dp->d_ino, dumpinomap)) {
399 				CLRINO(dp->d_ino, dumpinomap);
400 				*tapesize -= blockest(ip);
401 			}
402 			/*
403 			 * Add back to dumpdirmap and remove from usedinomap
404 			 * to propagate nodump.
405 			 */
406 			if (mode == IFDIR) {
407 				SETINO(dp->d_ino, dumpdirmap);
408 				CLRINO(dp->d_ino, usedinomap);
409 				ret |= HASSUBDIRS;
410 			}
411 		} else {
412 			if (TSTINO(dp->d_ino, dumpinomap)) {
413 				ret |= HASDUMPEDFILE;
414 				if (ret & HASSUBDIRS)
415 					break;
416 			}
417 			if (TSTINO(dp->d_ino, dumpdirmap)) {
418 				ret |= HASSUBDIRS;
419 				if (ret & HASDUMPEDFILE)
420 					break;
421 			}
422 		}
423 	}
424 	return (ret);
425 }
426 
427 /*
428  * Dump passes 3 and 4.
429  *
430  * Dump the contents of an inode to tape.
431  */
432 void
433 dumpino(union dinode *dp, ino_t ino)
434 {
435 	int ind_level, cnt;
436 	off_t size;
437 	char buf[TP_BSIZE];
438 
439 	if (newtape) {
440 		newtape = 0;
441 		dumpmap(dumpinomap, TS_BITS, ino);
442 	}
443 	CLRINO(ino, dumpinomap);
444 	/*
445 	 * Zero out the size of a snapshot so that it will be dumped
446 	 * as a zero length file.
447 	 */
448 	if ((DIP(dp, di_flags) & SF_SNAPSHOT) != 0) {
449 		DIP(dp, di_size) = 0;
450 		DIP(dp, di_flags) &= ~SF_SNAPSHOT;
451 	}
452 	if (sblock->fs_magic == FS_UFS1_MAGIC) {
453 		spcl.c_mode = dp->dp1.di_mode;
454 		spcl.c_size = dp->dp1.di_size;
455 		spcl.c_atime = _time32_to_time(dp->dp1.di_atime);
456 		spcl.c_atimensec = dp->dp1.di_atimensec;
457 		spcl.c_mtime = _time32_to_time(dp->dp1.di_mtime);
458 		spcl.c_mtimensec = dp->dp1.di_mtimensec;
459 		spcl.c_birthtime = 0;
460 		spcl.c_birthtimensec = 0;
461 		spcl.c_rdev = dp->dp1.di_rdev;
462 		spcl.c_file_flags = dp->dp1.di_flags;
463 		spcl.c_uid = dp->dp1.di_uid;
464 		spcl.c_gid = dp->dp1.di_gid;
465 	} else {
466 		spcl.c_mode = dp->dp2.di_mode;
467 		spcl.c_size = dp->dp2.di_size;
468 		spcl.c_atime = _time64_to_time(dp->dp2.di_atime);
469 		spcl.c_atimensec = dp->dp2.di_atimensec;
470 		spcl.c_mtime = _time64_to_time(dp->dp2.di_mtime);
471 		spcl.c_mtimensec = dp->dp2.di_mtimensec;
472 		spcl.c_birthtime = _time64_to_time(dp->dp2.di_birthtime);
473 		spcl.c_birthtimensec = dp->dp2.di_birthnsec;
474 		spcl.c_rdev = dp->dp2.di_rdev;
475 		spcl.c_file_flags = dp->dp2.di_flags;
476 		spcl.c_uid = dp->dp2.di_uid;
477 		spcl.c_gid = dp->dp2.di_gid;
478 	}
479 	spcl.c_type = TS_INODE;
480 	spcl.c_count = 0;
481 	switch (DIP(dp, di_mode) & S_IFMT) {
482 
483 	case 0:
484 		/*
485 		 * Freed inode.
486 		 */
487 		return;
488 
489 	case S_IFLNK:
490 		/*
491 		 * Check for short symbolic link.
492 		 */
493 		if (DIP(dp, di_size) > 0 &&
494 		    DIP(dp, di_size) < sblock->fs_maxsymlinklen) {
495 			spcl.c_addr[0] = 1;
496 			spcl.c_count = 1;
497 			writeheader(ino);
498 			if (sblock->fs_magic == FS_UFS1_MAGIC)
499 				memmove(buf, (caddr_t)dp->dp1.di_db,
500 				    (u_long)DIP(dp, di_size));
501 			else
502 				memmove(buf, (caddr_t)dp->dp2.di_db,
503 				    (u_long)DIP(dp, di_size));
504 			buf[DIP(dp, di_size)] = '\0';
505 			writerec(buf, 0);
506 			return;
507 		}
508 		/* FALLTHROUGH */
509 
510 	case S_IFDIR:
511 	case S_IFREG:
512 		if (DIP(dp, di_size) > 0)
513 			break;
514 		/* FALLTHROUGH */
515 
516 	case S_IFIFO:
517 	case S_IFSOCK:
518 	case S_IFCHR:
519 	case S_IFBLK:
520 		writeheader(ino);
521 		return;
522 
523 	default:
524 		msg("Warning: undefined file type 0%o\n",
525 		    DIP(dp, di_mode) & IFMT);
526 		return;
527 	}
528 	if (DIP(dp, di_size) > NDADDR * sblock->fs_bsize)
529 		cnt = NDADDR * sblock->fs_frag;
530 	else
531 		cnt = howmany(DIP(dp, di_size), sblock->fs_fsize);
532 	if (sblock->fs_magic == FS_UFS1_MAGIC)
533 		ufs1_blksout(&dp->dp1.di_db[0], cnt, ino);
534 	else
535 		ufs2_blksout(&dp->dp2.di_db[0], cnt, ino);
536 	if ((size = DIP(dp, di_size) - NDADDR * sblock->fs_bsize) <= 0)
537 		return;
538 	for (ind_level = 0; ind_level < NIADDR; ind_level++) {
539 		dmpindir(ino, DIP(dp, di_ib[ind_level]), ind_level, &size);
540 		if (size <= 0)
541 			return;
542 	}
543 }
544 
545 /*
546  * Read indirect blocks, and pass the data blocks to be dumped.
547  */
548 static void
549 dmpindir(ino_t ino, ufs2_daddr_t blk, int ind_level, off_t *size)
550 {
551 	union {
552 		ufs1_daddr_t ufs1[MAXBSIZE / sizeof(ufs1_daddr_t)];
553 		ufs2_daddr_t ufs2[MAXBSIZE / sizeof(ufs2_daddr_t)];
554 	} idblk;
555 	int i, cnt;
556 
557 	if (blk != 0)
558 		bread(fsbtodb(sblock, blk), (char *)&idblk,
559 		    (int)sblock->fs_bsize);
560 	else
561 		memset(&idblk, 0, sblock->fs_bsize);
562 	if (ind_level <= 0) {
563 		if (*size < NINDIR(sblock) * sblock->fs_bsize)
564 			cnt = howmany(*size, sblock->fs_fsize);
565 		else
566 			cnt = NINDIR(sblock) * sblock->fs_frag;
567 		*size -= NINDIR(sblock) * sblock->fs_bsize;
568 		if (sblock->fs_magic == FS_UFS1_MAGIC)
569 			ufs1_blksout(idblk.ufs1, cnt, ino);
570 		else
571 			ufs2_blksout(idblk.ufs2, cnt, ino);
572 		return;
573 	}
574 	ind_level--;
575 	for (i = 0; i < NINDIR(sblock); i++) {
576 		if (sblock->fs_magic == FS_UFS1_MAGIC)
577 			dmpindir(ino, idblk.ufs1[i], ind_level, size);
578 		else
579 			dmpindir(ino, idblk.ufs2[i], ind_level, size);
580 		if (*size <= 0)
581 			return;
582 	}
583 }
584 
585 /*
586  * Collect up the data into tape record sized buffers and output them.
587  */
588 void
589 ufs1_blksout(ufs1_daddr_t *blkp, int frags, ino_t ino)
590 {
591 	ufs1_daddr_t *bp;
592 	int i, j, count, blks, tbperdb;
593 
594 	blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
595 	tbperdb = sblock->fs_bsize >> tp_bshift;
596 	for (i = 0; i < blks; i += TP_NINDIR) {
597 		if (i + TP_NINDIR > blks)
598 			count = blks;
599 		else
600 			count = i + TP_NINDIR;
601 		for (j = i; j < count; j++)
602 			if (blkp[j / tbperdb] != 0)
603 				spcl.c_addr[j - i] = 1;
604 			else
605 				spcl.c_addr[j - i] = 0;
606 		spcl.c_count = count - i;
607 		writeheader(ino);
608 		bp = &blkp[i / tbperdb];
609 		for (j = i; j < count; j += tbperdb, bp++)
610 			if (*bp != 0) {
611 				if (j + tbperdb <= count)
612 					dumpblock(*bp, (int)sblock->fs_bsize);
613 				else
614 					dumpblock(*bp, (count - j) * TP_BSIZE);
615 			}
616 		spcl.c_type = TS_ADDR;
617 	}
618 }
619 
620 /*
621  * Collect up the data into tape record sized buffers and output them.
622  */
623 void
624 ufs2_blksout(ufs2_daddr_t *blkp, int frags, ino_t ino)
625 {
626 	ufs2_daddr_t *bp;
627 	int i, j, count, blks, tbperdb;
628 
629 	blks = howmany(frags * sblock->fs_fsize, TP_BSIZE);
630 	tbperdb = sblock->fs_bsize >> tp_bshift;
631 	for (i = 0; i < blks; i += TP_NINDIR) {
632 		if (i + TP_NINDIR > blks)
633 			count = blks;
634 		else
635 			count = i + TP_NINDIR;
636 		for (j = i; j < count; j++)
637 			if (blkp[j / tbperdb] != 0)
638 				spcl.c_addr[j - i] = 1;
639 			else
640 				spcl.c_addr[j - i] = 0;
641 		spcl.c_count = count - i;
642 		writeheader(ino);
643 		bp = &blkp[i / tbperdb];
644 		for (j = i; j < count; j += tbperdb, bp++)
645 			if (*bp != 0) {
646 				if (j + tbperdb <= count)
647 					dumpblock(*bp, (int)sblock->fs_bsize);
648 				else
649 					dumpblock(*bp, (count - j) * TP_BSIZE);
650 			}
651 		spcl.c_type = TS_ADDR;
652 	}
653 }
654 
655 /*
656  * Dump a map to the tape.
657  */
658 void
659 dumpmap(char *map, int type, ino_t ino)
660 {
661 	int i;
662 	char *cp;
663 
664 	spcl.c_type = type;
665 	spcl.c_count = howmany(mapsize * sizeof(char), TP_BSIZE);
666 	writeheader(ino);
667 	for (i = 0, cp = map; i < spcl.c_count; i++, cp += TP_BSIZE)
668 		writerec(cp, 0);
669 }
670 
671 /*
672  * Write a header record to the dump tape.
673  */
674 void
675 writeheader(ino_t ino)
676 {
677 	int32_t sum, cnt, *lp;
678 
679 	spcl.c_inumber = ino;
680 	spcl.c_magic = FS_UFS2_MAGIC;
681 	spcl.c_checksum = 0;
682 	lp = (int32_t *)&spcl;
683 	sum = 0;
684 	cnt = sizeof(union u_spcl) / (4 * sizeof(int32_t));
685 	while (--cnt >= 0) {
686 		sum += *lp++;
687 		sum += *lp++;
688 		sum += *lp++;
689 		sum += *lp++;
690 	}
691 	spcl.c_checksum = CHECKSUM - sum;
692 	writerec((char *)&spcl, 1);
693 }
694 
695 union dinode *
696 getino(ino_t inum, int *modep)
697 {
698 	static ino_t minino, maxino;
699 	static caddr_t inoblock;
700 	struct ufs1_dinode *dp1;
701 	struct ufs2_dinode *dp2;
702 
703 	if (inoblock == NULL && (inoblock = malloc(sblock->fs_bsize)) == NULL)
704 		quit("cannot allocate inode memory.\n");
705 	curino = inum;
706 	if (inum >= minino && inum < maxino)
707 		goto gotit;
708 	bread(fsbtodb(sblock, ino_to_fsba(sblock, inum)), inoblock,
709 	    (int)sblock->fs_bsize);
710 	minino = inum - (inum % INOPB(sblock));
711 	maxino = minino + INOPB(sblock);
712 gotit:
713 	if (sblock->fs_magic == FS_UFS1_MAGIC) {
714 		dp1 = &((struct ufs1_dinode *)inoblock)[inum - minino];
715 		*modep = (dp1->di_mode & IFMT);
716 		return ((union dinode *)dp1);
717 	}
718 	dp2 = &((struct ufs2_dinode *)inoblock)[inum - minino];
719 	*modep = (dp2->di_mode & IFMT);
720 	return ((union dinode *)dp2);
721 }
722 
723 /*
724  * Read a chunk of data from the disk.
725  * Try to recover from hard errors by reading in sector sized pieces.
726  * Error recovery is attempted at most BREADEMAX times before seeking
727  * consent from the operator to continue.
728  */
729 int	breaderrors = 0;
730 #define	BREADEMAX 32
731 
732 void
733 bread(ufs2_daddr_t blkno, char *buf, int size)
734 {
735 	int secsize, bytes, resid, xfer, base, cnt, i;
736 	static char *tmpbuf;
737 	off_t offset;
738 
739 loop:
740 	offset = blkno << dev_bshift;
741 	secsize = sblock->fs_fsize;
742 	base = offset % secsize;
743 	resid = size % secsize;
744 	/*
745 	 * If the transfer request starts or ends on a non-sector
746 	 * boundary, we must read the entire sector and copy out
747 	 * just the part that we need.
748 	 */
749 	if (base == 0 && resid == 0) {
750 		cnt = cread(diskfd, buf, size, offset);
751 		if (cnt == size)
752 			return;
753 	} else {
754 		if (tmpbuf == NULL && (tmpbuf = malloc(secsize)) == 0)
755 			quit("buffer malloc failed\n");
756 		xfer = 0;
757 		bytes = size;
758 		if (base != 0) {
759 			cnt = cread(diskfd, tmpbuf, secsize, offset - base);
760 			if (cnt != secsize)
761 				goto bad;
762 			xfer = secsize - base;
763 			offset += xfer;
764 			bytes -= xfer;
765 			resid = bytes % secsize;
766 			memcpy(buf, &tmpbuf[base], xfer);
767 		}
768 		if (bytes >= secsize) {
769 			cnt = cread(diskfd, &buf[xfer], bytes - resid, offset);
770 			if (cnt != bytes - resid)
771 				goto bad;
772 			xfer += cnt;
773 			offset += cnt;
774 		}
775 		if (resid == 0)
776 			return;
777 		cnt = cread(diskfd, tmpbuf, secsize, offset);
778 		if (cnt == secsize) {
779 			memcpy(&buf[xfer], tmpbuf, resid);
780 			return;
781 		}
782 	}
783 bad:
784 	if (blkno + (size / dev_bsize) > fsbtodb(sblock, sblock->fs_size)) {
785 		/*
786 		 * Trying to read the final fragment.
787 		 *
788 		 * NB - dump only works in TP_BSIZE blocks, hence
789 		 * rounds `dev_bsize' fragments up to TP_BSIZE pieces.
790 		 * It should be smarter about not actually trying to
791 		 * read more than it can get, but for the time being
792 		 * we punt and scale back the read only when it gets
793 		 * us into trouble. (mkm 9/25/83)
794 		 */
795 		size -= dev_bsize;
796 		goto loop;
797 	}
798 	if (cnt == -1)
799 		msg("read error from %s: %s: [block %jd]: count=%d\n",
800 			disk, strerror(errno), (intmax_t)blkno, size);
801 	else
802 		msg("short read error from %s: [block %jd]: count=%d, got=%d\n",
803 			disk, (intmax_t)blkno, size, cnt);
804 	if (++breaderrors > BREADEMAX) {
805 		msg("More than %d block read errors from %s\n",
806 			BREADEMAX, disk);
807 		broadcast("DUMP IS AILING!\n");
808 		msg("This is an unrecoverable error.\n");
809 		if (!query("Do you want to attempt to continue?")){
810 			dumpabort(0);
811 			/*NOTREACHED*/
812 		} else
813 			breaderrors = 0;
814 	}
815 	/*
816 	 * Zero buffer, then try to read each sector of buffer separately,
817 	 * and bypass the cache.
818 	 */
819 	memset(buf, 0, size);
820 	for (i = 0; i < size; i += dev_bsize, buf += dev_bsize, blkno++) {
821 		if ((cnt = pread(diskfd, buf, (int)dev_bsize,
822 		    ((off_t)blkno << dev_bshift))) == dev_bsize)
823 			continue;
824 		if (cnt == -1) {
825 			msg("read error from %s: %s: [sector %jd]: count=%ld\n",
826 			    disk, strerror(errno), (intmax_t)blkno, dev_bsize);
827 			continue;
828 		}
829 		msg("short read from %s: [sector %jd]: count=%ld, got=%d\n",
830 		    disk, (intmax_t)blkno, dev_bsize, cnt);
831 	}
832 }
833