xref: /dragonfly/sbin/hammer/cmd_recover.c (revision 9e6611d4)
1 /*
2  * Copyright (c) 2010 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@backplane.com>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 #include "hammer.h"
36 
37 #include <sys/tree.h>
38 
39 struct recover_dict {
40 	struct recover_dict *next;
41 	struct recover_dict *parent;
42 	int64_t	obj_id;
43 	uint8_t obj_type;
44 	uint8_t flags;
45 	uint16_t pfs_id;
46 	int64_t	size;
47 	char	*name;
48 };
49 
50 #define DICTF_MADEDIR	0x01
51 #define DICTF_MADEFILE	0x02
52 #define DICTF_PARENT	0x04	/* parent attached for real */
53 #define DICTF_TRAVERSED	0x80
54 
55 typedef struct bigblock {
56 	RB_ENTRY(bigblock) entry;
57 	hammer_off_t phys_offset; /* zone-2 */
58 	struct hammer_blockmap_layer1 layer1;
59 	struct hammer_blockmap_layer2 layer2;
60 } *bigblock_t;
61 
62 static void recover_top(char *ptr, hammer_off_t offset);
63 static void recover_elm(hammer_btree_leaf_elm_t leaf);
64 static struct recover_dict *get_dict(int64_t obj_id, uint16_t pfs_id);
65 static char *recover_path(struct recover_dict *dict);
66 static void sanitize_string(char *str);
67 static hammer_off_t scan_raw_limit(void);
68 static void scan_bigblocks(int target_zone);
69 static void free_bigblocks(void);
70 static void add_bigblock_entry(hammer_off_t offset,
71 	hammer_blockmap_layer1_t layer1, hammer_blockmap_layer2_t layer2);
72 static bigblock_t get_bigblock_entry(hammer_off_t offset);
73 
74 static const char *TargetDir;
75 static int CachedFd = -1;
76 static char *CachedPath;
77 
78 static int
79 bigblock_cmp(bigblock_t b1, bigblock_t b2)
80 {
81 	if (b1->phys_offset < b2->phys_offset)
82 		return(-1);
83 	if (b1->phys_offset > b2->phys_offset)
84 		return(1);
85 	return(0);
86 }
87 
88 RB_HEAD(bigblock_rb_tree, bigblock) ZoneTree = RB_INITIALIZER(&ZoneTree);
89 RB_PROTOTYPE2(bigblock_rb_tree, bigblock, entry, bigblock_cmp, hammer_off_t);
90 RB_GENERATE2(bigblock_rb_tree, bigblock, entry, bigblock_cmp, hammer_off_t,
91 	phys_offset);
92 
93 /*
94  * There was a hidden bug here while iterating zone-2 offset as
95  * shown in an example below.
96  *
97  * If a volume was once used as HAMMER filesystem which consists of
98  * multiple volumes whose usage has reached beyond the first volume,
99  * and then later re-formatted only using 1 volume, hammer recover is
100  * likely to hit assertion in get_buffer() due to having access to
101  * invalid volume (vol1,2,...) from old filesystem data.
102  *
103  * To avoid this, now the command only scans upto the last big-block
104  * that's actually used for filesystem data or meta-data at the moment,
105  * if all layer1/2 entries have correct CRC values. This also avoids
106  * recovery of irrelevant files from old filesystem.
107  *
108  * It also doesn't scan beyond append offset of big-blocks in B-Tree
109  * zone to avoid recovery of irrelevant files from old filesystem,
110  * if layer1/2 entries for those big-blocks have correct CRC values.
111  *
112  * |-----vol0-----|-----vol1-----|-----vol2-----| old filesystem
113  * <-----------------------> used by old filesystem
114  *
115  * |-----vol0-----| new filesystem
116  * <-----> used by new filesystem
117  *        <-------> unused, invalid data from old filesystem
118  *              <-> B-Tree nodes likely to point to vol1
119  */
120 
121 void
122 hammer_cmd_recover(char **av, int ac)
123 {
124 	buffer_info_t data_buffer;
125 	volume_info_t volume;
126 	bigblock_t b = NULL;
127 	hammer_off_t off;
128 	hammer_off_t off_end;
129 	hammer_off_t off_blk;
130 	hammer_off_t raw_limit = 0;
131 	hammer_off_t zone_limit = 0;
132 	char *ptr;
133 	int i;
134 	int target_zone = HAMMER_ZONE_BTREE_INDEX;
135 	int full = 0;
136 	int quick = 0;
137 
138 	if (ac < 1) {
139 		errx(1, "hammer recover <target_dir> [full|quick]");
140 		/* not reached */
141 	}
142 
143 	TargetDir = av[0];
144 	if (ac > 1) {
145 		if (!strcmp(av[1], "full"))
146 			full = 1;
147 		if (!strcmp(av[1], "quick"))
148 			quick = 1;
149 	}
150 	assert(!full || !quick);
151 
152 	if (mkdir(TargetDir, 0777) == -1) {
153 		if (errno != EEXIST) {
154 			err(1, "mkdir");
155 			/* not reached */
156 		}
157 	}
158 
159 	printf("Running %sraw scan of HAMMER image, recovering to %s\n",
160 		full ? "full " : quick ? "quick " : "",
161 		TargetDir);
162 
163 	if (!full) {
164 		scan_bigblocks(target_zone);
165 		raw_limit = scan_raw_limit();
166 		if (raw_limit) {
167 			raw_limit += HAMMER_BIGBLOCK_SIZE;
168 			assert(hammer_is_zone_raw_buffer(raw_limit));
169 		}
170 	}
171 
172 	if (quick) {
173 		assert(!full);
174 		if (!RB_EMPTY(&ZoneTree)) {
175 			printf("Found zone-%d big-blocks at\n", target_zone);
176 			RB_FOREACH(b, bigblock_rb_tree, &ZoneTree)
177 				printf("%016jx\n", b->phys_offset);
178 
179 			b = RB_MAX(bigblock_rb_tree, &ZoneTree);
180 			zone_limit = b->phys_offset + HAMMER_BIGBLOCK_SIZE;
181 			assert(hammer_is_zone_raw_buffer(zone_limit));
182 		}
183 	}
184 
185 	if (raw_limit || zone_limit) {
186 #define _fmt "Scanning zone-%d big-blocks till %016jx"
187 		if (!raw_limit) /* unlikely */
188 			printf(_fmt" ???", target_zone, zone_limit);
189 		else if (!zone_limit)
190 			printf(_fmt, HAMMER_ZONE_RAW_BUFFER_INDEX, raw_limit);
191 		else if (raw_limit >= zone_limit)
192 			printf(_fmt, target_zone, zone_limit);
193 		else /* unlikely */
194 			printf(_fmt" ???", HAMMER_ZONE_RAW_BUFFER_INDEX, raw_limit);
195 		printf("\n");
196 	}
197 
198 	data_buffer = NULL;
199 	for (i = 0; i < HAMMER_MAX_VOLUMES; i++) {
200 		volume = get_volume(i);
201 		if (volume == NULL)
202 			continue;
203 
204 		printf("Scanning volume %d size %s\n",
205 			volume->vol_no, sizetostr(volume->size));
206 		off = HAMMER_ENCODE_RAW_BUFFER(volume->vol_no, 0);
207 		off_end = off + HAMMER_VOL_BUF_SIZE(volume->ondisk);
208 
209 		while (off < off_end) {
210 			off_blk = off & HAMMER_BIGBLOCK_MASK64;
211 			if (off_blk == 0)
212 				b = get_bigblock_entry(off);
213 
214 			if (raw_limit) {
215 				if (off >= raw_limit) {
216 					printf("Done %016jx\n", (uintmax_t)off);
217 					goto end;
218 				}
219 			}
220 			if (zone_limit) {
221 				if (off >= zone_limit) {
222 					printf("Done %016jx\n", (uintmax_t)off);
223 					goto end;
224 				}
225 				if (b == NULL) {
226 					off = HAMMER_ZONE_LAYER2_NEXT_OFFSET(off);
227 					continue;
228 				}
229 			}
230 
231 			if (b) {
232 				if (hammer_crc_test_layer1(HammerVersion,
233 							   &b->layer1) &&
234 				    hammer_crc_test_layer2(HammerVersion,
235 							   &b->layer2) &&
236 				    off_blk >= b->layer2.append_off) {
237 					off = HAMMER_ZONE_LAYER2_NEXT_OFFSET(off);
238 					continue;
239 				}
240 			}
241 
242 			ptr = get_buffer_data(off, &data_buffer, 0);
243 			if (ptr)
244 				recover_top(ptr, off);
245 			off += HAMMER_BUFSIZE;
246 		}
247 	}
248 end:
249 	rel_buffer(data_buffer);
250 	free_bigblocks();
251 
252 	if (CachedPath) {
253 		free(CachedPath);
254 		close(CachedFd);
255 		CachedPath = NULL;
256 		CachedFd = -1;
257 	}
258 }
259 
260 static __inline
261 void
262 print_node(hammer_node_ondisk_t node, hammer_off_t offset)
263 {
264 	char buf[HAMMER_BTREE_LEAF_ELMS + 1];
265 	int maxcount = hammer_node_max_elements(node->type);
266 	int i;
267 
268 	for (i = 0; i < node->count && i < maxcount; ++i)
269 		buf[i] = hammer_elm_btype(&node->elms[i]);
270 	buf[i] = '\0';
271 
272 	printf("%016jx %c %d %s\n", offset, node->type, node->count, buf);
273 }
274 
275 /*
276  * Top level recovery processor.  Assume the data is a B-Tree node.
277  * If the CRC is good we attempt to process the node, building the
278  * object space and creating the dictionary as we go.
279  */
280 static
281 void
282 recover_top(char *ptr, hammer_off_t offset)
283 {
284 	hammer_node_ondisk_t node;
285 	hammer_btree_elm_t elm;
286 	int maxcount;
287 	int i;
288 	int isnode;
289 
290 	for (node = (void *)ptr; (char *)node < ptr + HAMMER_BUFSIZE; ++node) {
291 		isnode = hammer_crc_test_btree(HammerVersion, node);
292 		maxcount = hammer_node_max_elements(node->type);
293 
294 		if (DebugOpt) {
295 			if (isnode)
296 				print_node(node, offset);
297 			else if (DebugOpt > 1)
298 				printf("%016jx -\n", offset);
299 		}
300 		offset += sizeof(*node);
301 
302 		if (isnode && node->type == HAMMER_BTREE_TYPE_LEAF) {
303 			for (i = 0; i < node->count && i < maxcount; ++i) {
304 				elm = &node->elms[i];
305 				if (elm->base.btype == HAMMER_BTREE_TYPE_RECORD)
306 					recover_elm(&elm->leaf);
307 			}
308 		}
309 	}
310 }
311 
312 static
313 void
314 recover_elm(hammer_btree_leaf_elm_t leaf)
315 {
316 	buffer_info_t data_buffer = NULL;
317 	struct recover_dict *dict;
318 	struct recover_dict *dict2;
319 	hammer_data_ondisk_t ondisk;
320 	hammer_off_t data_offset;
321 	struct stat st;
322 	int chunk;
323 	int len;
324 	int zfill;
325 	int64_t file_offset;
326 	uint16_t pfs_id;
327 	size_t nlen;
328 	int fd;
329 	char *name;
330 	char *path1;
331 	char *path2;
332 
333 	/*
334 	 * Ignore deleted records
335 	 */
336 	if (leaf->delete_ts)
337 		return;
338 
339 	/*
340 	 * If we're running full scan, it's possible that data_offset
341 	 * refers to old filesystem data that we can't physically access.
342 	 */
343 	data_offset = leaf->data_offset;
344 	if (get_volume(HAMMER_VOL_DECODE(data_offset)) == NULL)
345 		return;
346 
347 	if (data_offset != 0)
348 		ondisk = get_buffer_data(data_offset, &data_buffer, 0);
349 	else
350 		ondisk = NULL;
351 	if (ondisk == NULL)
352 		goto done;
353 
354 	len = leaf->data_len;
355 	chunk = HAMMER_BUFSIZE - ((int)data_offset & HAMMER_BUFMASK);
356 	if (chunk > len)
357 		chunk = len;
358 
359 	if (len < 0 || len > HAMMER_XBUFSIZE || len > chunk)
360 		goto done;
361 
362 	pfs_id = lo_to_pfs(leaf->base.localization);
363 
364 	/*
365 	 * Note that meaning of leaf->base.obj_id differs depending
366 	 * on record type.  For a direntry, leaf->base.obj_id points
367 	 * to its parent inode that this entry is a part of, but not
368 	 * its corresponding inode.
369 	 */
370 	dict = get_dict(leaf->base.obj_id, pfs_id);
371 
372 	switch(leaf->base.rec_type) {
373 	case HAMMER_RECTYPE_INODE:
374 		/*
375 		 * We found an inode which also tells us where the file
376 		 * or directory is in the directory hierarchy.
377 		 */
378 		if (VerboseOpt) {
379 			printf("inode %016jx:%05d found\n",
380 				(uintmax_t)leaf->base.obj_id, pfs_id);
381 		}
382 		path1 = recover_path(dict);
383 
384 		/*
385 		 * Attach the inode to its parent.  This isn't strictly
386 		 * necessary because the information is also in the
387 		 * directory entries, but if we do not find the directory
388 		 * entry this ensures that the files will still be
389 		 * reasonably well organized in their proper directories.
390 		 */
391 		if ((dict->flags & DICTF_PARENT) == 0 &&
392 		    dict->obj_id != HAMMER_OBJID_ROOT &&
393 		    ondisk->inode.parent_obj_id != 0) {
394 			dict->flags |= DICTF_PARENT;
395 			dict->parent = get_dict(ondisk->inode.parent_obj_id,
396 						pfs_id);
397 			if (dict->parent &&
398 			    (dict->parent->flags & DICTF_MADEDIR) == 0) {
399 				dict->parent->flags |= DICTF_MADEDIR;
400 				path2 = recover_path(dict->parent);
401 				printf("mkdir %s\n", path2);
402 				mkdir(path2, 0777);
403 				free(path2);
404 				path2 = NULL;
405 			}
406 		}
407 		if (dict->obj_type == 0)
408 			dict->obj_type = ondisk->inode.obj_type;
409 		dict->size = ondisk->inode.size;
410 		path2 = recover_path(dict);
411 
412 		if (lstat(path1, &st) == 0) {
413 			if (ondisk->inode.obj_type == HAMMER_OBJTYPE_REGFILE) {
414 				truncate(path1, dict->size);
415 				/* chmod(path1, 0666); */
416 			}
417 			if (strcmp(path1, path2)) {
418 				printf("Rename (inode) %s -> %s\n", path1, path2);
419 				rename(path1, path2);
420 			}
421 		} else if (ondisk->inode.obj_type == HAMMER_OBJTYPE_REGFILE) {
422 			printf("mkinode (file) %s\n", path2);
423 			fd = open(path2, O_RDWR|O_CREAT, 0666);
424 			if (fd > 0)
425 				close(fd);
426 		} else if (ondisk->inode.obj_type == HAMMER_OBJTYPE_DIRECTORY) {
427 			printf("mkinode (dir) %s\n", path2);
428 			mkdir(path2, 0777);
429 			dict->flags |= DICTF_MADEDIR;
430 		}
431 		free(path1);
432 		free(path2);
433 		break;
434 	case HAMMER_RECTYPE_DATA:
435 		/*
436 		 * File record data
437 		 */
438 		if (leaf->base.obj_id == 0)
439 			break;
440 		if (VerboseOpt) {
441 			printf("inode %016jx:%05d data %016jx,%d\n",
442 				(uintmax_t)leaf->base.obj_id,
443 				pfs_id,
444 				(uintmax_t)leaf->base.key - len,
445 				len);
446 		}
447 
448 		/*
449 		 * Update the dictionary entry
450 		 */
451 		if (dict->obj_type == 0)
452 			dict->obj_type = HAMMER_OBJTYPE_REGFILE;
453 
454 		/*
455 		 * If the parent directory has not been created we
456 		 * have to create it (typically a PFS%05d)
457 		 */
458 		if (dict->parent &&
459 		    (dict->parent->flags & DICTF_MADEDIR) == 0) {
460 			dict->parent->flags |= DICTF_MADEDIR;
461 			path2 = recover_path(dict->parent);
462 			printf("mkdir %s\n", path2);
463 			mkdir(path2, 0777);
464 			free(path2);
465 			path2 = NULL;
466 		}
467 
468 		/*
469 		 * Create the file if necessary, report file creations
470 		 */
471 		path1 = recover_path(dict);
472 		if (CachedPath && strcmp(CachedPath, path1) == 0)
473 			fd = CachedFd;
474 		else
475 			fd = open(path1, O_CREAT|O_RDWR, 0666);
476 		if (fd < 0) {
477 			printf("Unable to create %s: %s\n",
478 				path1, strerror(errno));
479 			free(path1);
480 			break;
481 		}
482 		if ((dict->flags & DICTF_MADEFILE) == 0) {
483 			dict->flags |= DICTF_MADEFILE;
484 			printf("mkfile %s\n", path1);
485 		}
486 
487 		/*
488 		 * And write the record.  A HAMMER data block is aligned
489 		 * and may contain trailing zeros after the file EOF.  The
490 		 * inode record is required to get the actual file size.
491 		 *
492 		 * However, when the inode record is not available
493 		 * we can do a sparse write and that will get it right
494 		 * most of the time even if the inode record is never
495 		 * found.
496 		 */
497 		file_offset = (int64_t)leaf->base.key - len;
498 		lseek(fd, (off_t)file_offset, SEEK_SET);
499 		while (len) {
500 			if (dict->size == -1) {
501 				for (zfill = chunk - 1; zfill >= 0; --zfill) {
502 					if (((char *)ondisk)[zfill])
503 						break;
504 				}
505 				++zfill;
506 			} else {
507 				zfill = chunk;
508 			}
509 
510 			if (zfill)
511 				write(fd, ondisk, zfill);
512 			if (zfill < chunk)
513 				lseek(fd, chunk - zfill, SEEK_CUR);
514 
515 			len -= chunk;
516 			data_offset += chunk;
517 			file_offset += chunk;
518 			ondisk = get_buffer_data(data_offset, &data_buffer, 0);
519 			if (ondisk == NULL)
520 				break;
521 			chunk = HAMMER_BUFSIZE -
522 				((int)data_offset & HAMMER_BUFMASK);
523 			if (chunk > len)
524 				chunk = len;
525 		}
526 		if (dict->size >= 0 && file_offset > dict->size) {
527 			ftruncate(fd, dict->size);
528 			/* fchmod(fd, 0666); */
529 		}
530 
531 		if (fd == CachedFd) {
532 			free(path1);
533 		} else if (CachedPath) {
534 			free(CachedPath);
535 			close(CachedFd);
536 			CachedPath = path1;
537 			CachedFd = fd;
538 		} else {
539 			CachedPath = path1;
540 			CachedFd = fd;
541 		}
542 		break;
543 	case HAMMER_RECTYPE_DIRENTRY:
544 		nlen = len - HAMMER_ENTRY_NAME_OFF;
545 		if ((int)nlen < 0)	/* illegal length */
546 			break;
547 		if (ondisk->entry.obj_id == 0 ||
548 		    ondisk->entry.obj_id == HAMMER_OBJID_ROOT) {
549 			break;
550 		}
551 		name = malloc(nlen + 1);
552 		bcopy(ondisk->entry.name, name, nlen);
553 		name[nlen] = 0;
554 		sanitize_string(name);
555 
556 		if (VerboseOpt) {
557 			printf("dir %016jx:%05d entry %016jx \"%s\"\n",
558 				(uintmax_t)leaf->base.obj_id,
559 				pfs_id,
560 				(uintmax_t)ondisk->entry.obj_id,
561 				name);
562 		}
563 
564 		/*
565 		 * We can't deal with hardlinks so if the object already
566 		 * has a name assigned to it we just keep using that name.
567 		 */
568 		dict2 = get_dict(ondisk->entry.obj_id, pfs_id);
569 		path1 = recover_path(dict2);
570 
571 		if (dict2->name == NULL)
572 			dict2->name = name;
573 		else
574 			free(name);
575 
576 		/*
577 		 * Attach dict2 to its directory (dict), create the
578 		 * directory (dict) if necessary.  We must ensure
579 		 * that the directory entry exists in order to be
580 		 * able to properly rename() the file without creating
581 		 * a namespace conflict.
582 		 */
583 		if ((dict2->flags & DICTF_PARENT) == 0) {
584 			dict2->flags |= DICTF_PARENT;
585 			dict2->parent = dict;
586 			if ((dict->flags & DICTF_MADEDIR) == 0) {
587 				dict->flags |= DICTF_MADEDIR;
588 				path2 = recover_path(dict);
589 				printf("mkdir %s\n", path2);
590 				mkdir(path2, 0777);
591 				free(path2);
592 				path2 = NULL;
593 			}
594 		}
595 		path2 = recover_path(dict2);
596 		if (strcmp(path1, path2) != 0 && lstat(path1, &st) == 0) {
597 			printf("Rename (entry) %s -> %s\n", path1, path2);
598 			rename(path1, path2);
599 		}
600 		free(path1);
601 		free(path2);
602 		break;
603 	default:
604 		/*
605 		 * Ignore any other record types
606 		 */
607 		break;
608 	}
609 done:
610 	rel_buffer(data_buffer);
611 }
612 
613 #define RD_HSIZE	32768
614 #define RD_HMASK	(RD_HSIZE - 1)
615 
616 struct recover_dict *RDHash[RD_HSIZE];
617 
618 static
619 struct recover_dict *
620 get_dict(int64_t obj_id, uint16_t pfs_id)
621 {
622 	struct recover_dict *dict;
623 	int i;
624 
625 	if (obj_id == 0)
626 		return(NULL);
627 
628 	i = crc32(&obj_id, sizeof(obj_id)) & RD_HMASK;
629 	for (dict = RDHash[i]; dict; dict = dict->next) {
630 		if (dict->obj_id == obj_id && dict->pfs_id == pfs_id)
631 			break;
632 	}
633 
634 	if (dict == NULL) {
635 		dict = malloc(sizeof(*dict));
636 		bzero(dict, sizeof(*dict));
637 		dict->obj_id = obj_id;
638 		dict->pfs_id = pfs_id;
639 		dict->next = RDHash[i];
640 		dict->size = -1;
641 		RDHash[i] = dict;
642 
643 		/*
644 		 * Always connect dangling dictionary entries to object 1
645 		 * (the root of the PFS).
646 		 *
647 		 * DICTF_PARENT will not be set until we know what the
648 		 * real parent directory object is.
649 		 */
650 		if (dict->obj_id != HAMMER_OBJID_ROOT)
651 			dict->parent = get_dict(HAMMER_OBJID_ROOT, pfs_id);
652 	}
653 	return(dict);
654 }
655 
656 struct path_info {
657 	enum { PI_FIGURE, PI_LOAD } state;
658 	uint16_t pfs_id;
659 	char *base;
660 	char *next;
661 	int len;
662 };
663 
664 static void recover_path_helper(struct recover_dict *, struct path_info *);
665 
666 static
667 char *
668 recover_path(struct recover_dict *dict)
669 {
670 	struct path_info info;
671 
672 	/* Find info.len first */
673 	bzero(&info, sizeof(info));
674 	info.state = PI_FIGURE;
675 	recover_path_helper(dict, &info);
676 
677 	/* Fill in the path */
678 	info.pfs_id = dict->pfs_id;
679 	info.base = malloc(info.len);
680 	info.next = info.base;
681 	info.state = PI_LOAD;
682 	recover_path_helper(dict, &info);
683 
684 	/* Return the path */
685 	return(info.base);
686 }
687 
688 #define STRLEN_OBJID	22	/* "obj_0x%016jx" */
689 #define STRLEN_PFSID	8	/* "PFS%05d" */
690 
691 static
692 void
693 recover_path_helper(struct recover_dict *dict, struct path_info *info)
694 {
695 	/*
696 	 * Calculate path element length
697 	 */
698 	dict->flags |= DICTF_TRAVERSED;
699 
700 	switch(info->state) {
701 	case PI_FIGURE:
702 		if (dict->obj_id == HAMMER_OBJID_ROOT)
703 			info->len += STRLEN_PFSID;
704 		else if (dict->name)
705 			info->len += strlen(dict->name);
706 		else
707 			info->len += STRLEN_OBJID;
708 		++info->len;
709 
710 		if (dict->parent &&
711 		    (dict->parent->flags & DICTF_TRAVERSED) == 0) {
712 			recover_path_helper(dict->parent, info);
713 		} else {
714 			info->len += strlen(TargetDir) + 1;
715 		}
716 		break;
717 	case PI_LOAD:
718 		if (dict->parent &&
719 		    (dict->parent->flags & DICTF_TRAVERSED) == 0) {
720 			recover_path_helper(dict->parent, info);
721 		} else {
722 			strcpy(info->next, TargetDir);
723 			info->next += strlen(info->next);
724 		}
725 
726 		*info->next++ = '/';
727 		if (dict->obj_id == HAMMER_OBJID_ROOT) {
728 			snprintf(info->next, STRLEN_PFSID + 1,
729 				"PFS%05d", info->pfs_id);
730 		} else if (dict->name) {
731 			strcpy(info->next, dict->name);
732 		} else {
733 			snprintf(info->next, STRLEN_OBJID + 1,
734 				"obj_0x%016jx", (uintmax_t)dict->obj_id);
735 		}
736 		info->next += strlen(info->next);
737 		break;
738 	}
739 	dict->flags &= ~DICTF_TRAVERSED;
740 }
741 
742 static
743 void
744 sanitize_string(char *str)
745 {
746 	while (*str) {
747 		if (!isprint(*str))
748 			*str = 'x';
749 		++str;
750 	}
751 }
752 
753 static
754 hammer_off_t
755 scan_raw_limit(void)
756 {
757 	volume_info_t volume;
758 	hammer_blockmap_t rootmap;
759 	hammer_blockmap_layer1_t layer1;
760 	hammer_blockmap_layer2_t layer2;
761 	buffer_info_t buffer1 = NULL;
762 	buffer_info_t buffer2 = NULL;
763 	hammer_off_t layer1_offset;
764 	hammer_off_t layer2_offset;
765 	hammer_off_t phys_offset;
766 	hammer_off_t block_offset;
767 	hammer_off_t offset = 0;
768 	int zone = HAMMER_ZONE_FREEMAP_INDEX;
769 
770 	volume = get_root_volume();
771 	rootmap = &volume->ondisk->vol0_blockmap[zone];
772 	assert(rootmap->phys_offset != 0);
773 
774 	for (phys_offset = HAMMER_ZONE_ENCODE(zone, 0);
775 	     phys_offset < HAMMER_ZONE_ENCODE(zone, HAMMER_OFF_LONG_MASK);
776 	     phys_offset += HAMMER_BLOCKMAP_LAYER2) {
777 		/*
778 		 * Dive layer 1.
779 		 */
780 		layer1_offset = rootmap->phys_offset +
781 				HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_offset);
782 		layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
783 
784 		if (!hammer_crc_test_layer1(HammerVersion, layer1)) {
785 			offset = 0; /* failed */
786 			goto end;
787 		}
788 		if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL)
789 			continue;
790 
791 		for (block_offset = 0;
792 		     block_offset < HAMMER_BLOCKMAP_LAYER2;
793 		     block_offset += HAMMER_BIGBLOCK_SIZE) {
794 			/*
795 			 * Dive layer 2, each entry represents a big-block.
796 			 */
797 			layer2_offset = layer1->phys_offset +
798 					HAMMER_BLOCKMAP_LAYER2_OFFSET(block_offset);
799 			layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
800 
801 			if (!hammer_crc_test_layer2(HammerVersion, layer2)) {
802 				offset = 0; /* failed */
803 				goto end;
804 			}
805 			if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
806 				break;
807 			} else if (layer2->zone && layer2->zone != zone) {
808 				offset = phys_offset + block_offset;
809 			}
810 		}
811 	}
812 end:
813 	rel_buffer(buffer1);
814 	rel_buffer(buffer2);
815 
816 	return(hammer_xlate_to_zone2(offset));
817 }
818 
819 static
820 void
821 scan_bigblocks(int target_zone)
822 {
823 	volume_info_t volume;
824 	hammer_blockmap_t rootmap;
825 	hammer_blockmap_layer1_t layer1;
826 	hammer_blockmap_layer2_t layer2;
827 	buffer_info_t buffer1 = NULL;
828 	buffer_info_t buffer2 = NULL;
829 	hammer_off_t layer1_offset;
830 	hammer_off_t layer2_offset;
831 	hammer_off_t phys_offset;
832 	hammer_off_t block_offset;
833 	hammer_off_t offset = 0;
834 	int zone = HAMMER_ZONE_FREEMAP_INDEX;
835 
836 	volume = get_root_volume();
837 	rootmap = &volume->ondisk->vol0_blockmap[zone];
838 	assert(rootmap->phys_offset != 0);
839 
840 	for (phys_offset = HAMMER_ZONE_ENCODE(zone, 0);
841 	     phys_offset < HAMMER_ZONE_ENCODE(zone, HAMMER_OFF_LONG_MASK);
842 	     phys_offset += HAMMER_BLOCKMAP_LAYER2) {
843 		/*
844 		 * Dive layer 1.
845 		 */
846 		layer1_offset = rootmap->phys_offset +
847 				HAMMER_BLOCKMAP_LAYER1_OFFSET(phys_offset);
848 		layer1 = get_buffer_data(layer1_offset, &buffer1, 0);
849 
850 		/*
851 		if (!hammer_crc_test_layer1(HammerVersion, layer1)) {
852 		}
853 		*/
854 		if (layer1->phys_offset == HAMMER_BLOCKMAP_UNAVAIL)
855 			continue;
856 
857 		for (block_offset = 0;
858 		     block_offset < HAMMER_BLOCKMAP_LAYER2;
859 		     block_offset += HAMMER_BIGBLOCK_SIZE) {
860 			offset = phys_offset + block_offset;
861 			/*
862 			 * Dive layer 2, each entry represents a big-block.
863 			 */
864 			layer2_offset = layer1->phys_offset +
865 					HAMMER_BLOCKMAP_LAYER2_OFFSET(block_offset);
866 			layer2 = get_buffer_data(layer2_offset, &buffer2, 0);
867 
868 			/*
869 			if (!hammer_crc_test_layer2(HammerVersion, layer2)) {
870 			}
871 			*/
872 			if (layer2->zone == target_zone) {
873 				add_bigblock_entry(offset, layer1, layer2);
874 			} else if (layer2->zone == HAMMER_ZONE_UNAVAIL_INDEX) {
875 				break;
876 			}
877 		}
878 	}
879 	rel_buffer(buffer1);
880 	rel_buffer(buffer2);
881 }
882 
883 static
884 void
885 free_bigblocks(void)
886 {
887 	bigblock_t b;
888 
889 	while ((b = RB_ROOT(&ZoneTree)) != NULL) {
890 		RB_REMOVE(bigblock_rb_tree, &ZoneTree, b);
891 		free(b);
892 	}
893 	assert(RB_EMPTY(&ZoneTree));
894 }
895 
896 static
897 void
898 add_bigblock_entry(hammer_off_t offset,
899 	hammer_blockmap_layer1_t layer1, hammer_blockmap_layer2_t layer2)
900 {
901 	bigblock_t b;
902 
903 	b = calloc(1, sizeof(*b));
904 	b->phys_offset = hammer_xlate_to_zone2(offset);
905 	assert((b->phys_offset & HAMMER_BIGBLOCK_MASK64) == 0);
906 	bcopy(layer1, &b->layer1, sizeof(*layer1));
907 	bcopy(layer2, &b->layer2, sizeof(*layer2));
908 
909 	RB_INSERT(bigblock_rb_tree, &ZoneTree, b);
910 }
911 
912 static
913 bigblock_t
914 get_bigblock_entry(hammer_off_t offset)
915 {
916 	bigblock_t b;
917 
918 	offset = hammer_xlate_to_zone2(offset);
919 	offset &= ~HAMMER_BIGBLOCK_MASK64;
920 
921 	b = RB_LOOKUP(bigblock_rb_tree, &ZoneTree, offset);
922 	if (b)
923 		return(b);
924 	return(NULL);
925 }
926