btrfs-progs: check: switch to iterating over the backref_tree
[btrfs-progs-unstable/devel.git] / cmds-restore.c
blobb491f083b72b808eaa5831907ab905fa53b72957
1 /*
2 * Copyright (C) 2011 Red Hat. All rights reserved.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public
6 * License v2 as published by the Free Software Foundation.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public
14 * License along with this program; if not, write to the
15 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
16 * Boston, MA 021110-1307, USA.
20 #include "kerncompat.h"
22 #include <ctype.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <unistd.h>
26 #include <fcntl.h>
27 #include <sys/stat.h>
28 #include <sys/types.h>
29 #include <lzo/lzoconf.h>
30 #include <lzo/lzo1x.h>
31 #include <zlib.h>
32 #include <regex.h>
33 #include <getopt.h>
34 #include <sys/types.h>
35 #include <sys/xattr.h>
37 #include "ctree.h"
38 #include "disk-io.h"
39 #include "print-tree.h"
40 #include "transaction.h"
41 #include "list.h"
42 #include "volumes.h"
43 #include "utils.h"
44 #include "commands.h"
46 static char fs_name[PATH_MAX];
47 static char path_name[PATH_MAX];
48 static char symlink_target[PATH_MAX];
49 static int get_snaps = 0;
50 static int verbose = 0;
51 static int restore_metadata = 0;
52 static int restore_symlinks = 0;
53 static int ignore_errors = 0;
54 static int overwrite = 0;
55 static int get_xattrs = 0;
56 static int dry_run = 0;
58 #define LZO_LEN 4
59 #define lzo1x_worst_compress(x) ((x) + ((x) / 16) + 64 + 3)
61 static int decompress_zlib(char *inbuf, char *outbuf, u64 compress_len,
62 u64 decompress_len)
64 z_stream strm;
65 int ret;
67 memset(&strm, 0, sizeof(strm));
68 ret = inflateInit(&strm);
69 if (ret != Z_OK) {
70 error("zlib init returned %d", ret);
71 return -1;
74 strm.avail_in = compress_len;
75 strm.next_in = (unsigned char *)inbuf;
76 strm.avail_out = decompress_len;
77 strm.next_out = (unsigned char *)outbuf;
78 ret = inflate(&strm, Z_NO_FLUSH);
79 if (ret != Z_STREAM_END) {
80 (void)inflateEnd(&strm);
81 error("zlib inflate failed: %d", ret);
82 return -1;
85 (void)inflateEnd(&strm);
86 return 0;
88 static inline size_t read_compress_length(unsigned char *buf)
90 __le32 dlen;
91 memcpy(&dlen, buf, LZO_LEN);
92 return le32_to_cpu(dlen);
95 static int decompress_lzo(struct btrfs_root *root, unsigned char *inbuf,
96 char *outbuf, u64 compress_len, u64 *decompress_len)
98 size_t new_len;
99 size_t in_len;
100 size_t out_len = 0;
101 size_t tot_len;
102 size_t tot_in;
103 int ret;
105 ret = lzo_init();
106 if (ret != LZO_E_OK) {
107 error("lzo init returned %d", ret);
108 return -1;
111 tot_len = read_compress_length(inbuf);
112 inbuf += LZO_LEN;
113 tot_in = LZO_LEN;
115 while (tot_in < tot_len) {
116 size_t mod_page;
117 size_t rem_page;
118 in_len = read_compress_length(inbuf);
120 if ((tot_in + LZO_LEN + in_len) > tot_len) {
121 error("bad compress length %lu",
122 (unsigned long)in_len);
123 return -1;
126 inbuf += LZO_LEN;
127 tot_in += LZO_LEN;
128 new_len = lzo1x_worst_compress(root->sectorsize);
129 ret = lzo1x_decompress_safe((const unsigned char *)inbuf, in_len,
130 (unsigned char *)outbuf,
131 (void *)&new_len, NULL);
132 if (ret != LZO_E_OK) {
133 error("lzo decompress failed: %d", ret);
134 return -1;
136 out_len += new_len;
137 outbuf += new_len;
138 inbuf += in_len;
139 tot_in += in_len;
142 * If the 4 byte header does not fit to the rest of the page we
143 * have to move to the next one, unless we read some garbage
145 mod_page = tot_in % root->sectorsize;
146 rem_page = root->sectorsize - mod_page;
147 if (rem_page < LZO_LEN) {
148 inbuf += rem_page;
149 tot_in += rem_page;
153 *decompress_len = out_len;
155 return 0;
158 static int decompress(struct btrfs_root *root, char *inbuf, char *outbuf,
159 u64 compress_len, u64 *decompress_len, int compress)
161 switch (compress) {
162 case BTRFS_COMPRESS_ZLIB:
163 return decompress_zlib(inbuf, outbuf, compress_len,
164 *decompress_len);
165 case BTRFS_COMPRESS_LZO:
166 return decompress_lzo(root, (unsigned char *)inbuf, outbuf,
167 compress_len, decompress_len);
168 default:
169 break;
172 error("invalid compression type: %d", compress);
173 return -1;
176 static int next_leaf(struct btrfs_root *root, struct btrfs_path *path)
178 int slot;
179 int level = 1;
180 int offset = 1;
181 struct extent_buffer *c;
182 struct extent_buffer *next = NULL;
184 again:
185 for (; level < BTRFS_MAX_LEVEL; level++) {
186 if (path->nodes[level])
187 break;
190 if (level >= BTRFS_MAX_LEVEL)
191 return 1;
193 slot = path->slots[level] + 1;
195 while(level < BTRFS_MAX_LEVEL) {
196 if (!path->nodes[level])
197 return 1;
199 slot = path->slots[level] + offset;
200 c = path->nodes[level];
201 if (slot >= btrfs_header_nritems(c)) {
202 level++;
203 if (level == BTRFS_MAX_LEVEL)
204 return 1;
205 offset = 1;
206 continue;
209 if (path->reada)
210 reada_for_search(root, path, level, slot, 0);
212 next = read_node_slot(root, c, slot);
213 if (extent_buffer_uptodate(next))
214 break;
215 offset++;
217 path->slots[level] = slot;
218 while(1) {
219 level--;
220 c = path->nodes[level];
221 free_extent_buffer(c);
222 path->nodes[level] = next;
223 path->slots[level] = 0;
224 if (!level)
225 break;
226 if (path->reada)
227 reada_for_search(root, path, level, 0, 0);
228 next = read_node_slot(root, next, 0);
229 if (!extent_buffer_uptodate(next))
230 goto again;
232 return 0;
235 static int copy_one_inline(struct btrfs_root *root, int fd,
236 struct btrfs_path *path, u64 pos)
238 struct extent_buffer *leaf = path->nodes[0];
239 struct btrfs_file_extent_item *fi;
240 char buf[4096];
241 char *outbuf;
242 u64 ram_size;
243 ssize_t done;
244 unsigned long ptr;
245 int ret;
246 int len;
247 int inline_item_len;
248 int compress;
250 fi = btrfs_item_ptr(leaf, path->slots[0],
251 struct btrfs_file_extent_item);
252 ptr = btrfs_file_extent_inline_start(fi);
253 len = btrfs_file_extent_inline_len(leaf, path->slots[0], fi);
254 inline_item_len = btrfs_file_extent_inline_item_len(leaf, btrfs_item_nr(path->slots[0]));
255 read_extent_buffer(leaf, buf, ptr, inline_item_len);
257 compress = btrfs_file_extent_compression(leaf, fi);
258 if (compress == BTRFS_COMPRESS_NONE) {
259 done = pwrite(fd, buf, len, pos);
260 if (done < len) {
261 fprintf(stderr, "Short inline write, wanted %d, did "
262 "%zd: %d\n", len, done, errno);
263 return -1;
265 return 0;
268 ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
269 outbuf = calloc(1, ram_size);
270 if (!outbuf) {
271 error("not enough memory");
272 return -ENOMEM;
275 ret = decompress(root, buf, outbuf, len, &ram_size, compress);
276 if (ret) {
277 free(outbuf);
278 return ret;
281 done = pwrite(fd, outbuf, ram_size, pos);
282 free(outbuf);
283 if (done < ram_size) {
284 fprintf(stderr, "Short compressed inline write, wanted %Lu, "
285 "did %zd: %d\n", ram_size, done, errno);
286 return -1;
289 return 0;
292 static int copy_one_extent(struct btrfs_root *root, int fd,
293 struct extent_buffer *leaf,
294 struct btrfs_file_extent_item *fi, u64 pos)
296 struct btrfs_multi_bio *multi = NULL;
297 struct btrfs_device *device;
298 char *inbuf, *outbuf = NULL;
299 ssize_t done, total = 0;
300 u64 bytenr;
301 u64 ram_size;
302 u64 disk_size;
303 u64 num_bytes;
304 u64 length;
305 u64 size_left;
306 u64 dev_bytenr;
307 u64 offset;
308 u64 count = 0;
309 int compress;
310 int ret;
311 int dev_fd;
312 int mirror_num = 1;
313 int num_copies;
315 compress = btrfs_file_extent_compression(leaf, fi);
316 bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
317 disk_size = btrfs_file_extent_disk_num_bytes(leaf, fi);
318 ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
319 offset = btrfs_file_extent_offset(leaf, fi);
320 num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
321 size_left = disk_size;
322 if (compress == BTRFS_COMPRESS_NONE)
323 bytenr += offset;
325 if (verbose && offset)
326 printf("offset is %Lu\n", offset);
327 /* we found a hole */
328 if (disk_size == 0)
329 return 0;
331 inbuf = malloc(size_left);
332 if (!inbuf) {
333 error("not enough memory\n");
334 return -ENOMEM;
337 if (compress != BTRFS_COMPRESS_NONE) {
338 outbuf = calloc(1, ram_size);
339 if (!outbuf) {
340 error("not enough memory");
341 free(inbuf);
342 return -ENOMEM;
345 again:
346 length = size_left;
347 ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
348 bytenr, &length, &multi, mirror_num, NULL);
349 if (ret) {
350 error("cannot map block logical %llu length %llu: %d",
351 (unsigned long long)bytenr,
352 (unsigned long long)length, ret);
353 goto out;
355 device = multi->stripes[0].dev;
356 dev_fd = device->fd;
357 device->total_ios++;
358 dev_bytenr = multi->stripes[0].physical;
359 kfree(multi);
361 if (size_left < length)
362 length = size_left;
364 done = pread(dev_fd, inbuf+count, length, dev_bytenr);
365 /* Need both checks, or we miss negative values due to u64 conversion */
366 if (done < 0 || done < length) {
367 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
368 bytenr, length);
369 mirror_num++;
370 /* mirror_num is 1-indexed, so num_copies is a valid mirror. */
371 if (mirror_num > num_copies) {
372 ret = -1;
373 error("exhausted mirrors trying to read (%d > %d)",
374 mirror_num, num_copies);
375 goto out;
377 fprintf(stderr, "Trying another mirror\n");
378 goto again;
381 mirror_num = 1;
382 size_left -= length;
383 count += length;
384 bytenr += length;
385 if (size_left)
386 goto again;
388 if (compress == BTRFS_COMPRESS_NONE) {
389 while (total < num_bytes) {
390 done = pwrite(fd, inbuf+total, num_bytes-total,
391 pos+total);
392 if (done < 0) {
393 ret = -1;
394 error("cannot write data: %d %s", errno, strerror(errno));
395 goto out;
397 total += done;
399 ret = 0;
400 goto out;
403 ret = decompress(root, inbuf, outbuf, disk_size, &ram_size, compress);
404 if (ret) {
405 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
406 bytenr, length);
407 mirror_num++;
408 if (mirror_num >= num_copies) {
409 ret = -1;
410 goto out;
412 fprintf(stderr, "Trying another mirror\n");
413 goto again;
416 while (total < num_bytes) {
417 done = pwrite(fd, outbuf + offset + total,
418 num_bytes - total,
419 pos + total);
420 if (done < 0) {
421 ret = -1;
422 goto out;
424 total += done;
426 out:
427 free(inbuf);
428 free(outbuf);
429 return ret;
432 enum loop_response {
433 LOOP_STOP,
434 LOOP_CONTINUE,
435 LOOP_DONTASK
438 static enum loop_response ask_to_continue(const char *file)
440 char buf[2];
441 char *ret;
443 printf("We seem to be looping a lot on %s, do you want to keep going "
444 "on ? (y/N/a): ", file);
445 again:
446 ret = fgets(buf, 2, stdin);
447 if (*ret == '\n' || tolower(*ret) == 'n')
448 return LOOP_STOP;
449 if (tolower(*ret) == 'a')
450 return LOOP_DONTASK;
451 if (tolower(*ret) != 'y') {
452 printf("Please enter one of 'y', 'n', or 'a': ");
453 goto again;
456 return LOOP_CONTINUE;
460 static int set_file_xattrs(struct btrfs_root *root, u64 inode,
461 int fd, const char *file_name)
463 struct btrfs_key key;
464 struct btrfs_path *path;
465 struct extent_buffer *leaf;
466 struct btrfs_dir_item *di;
467 u32 name_len = 0;
468 u32 data_len = 0;
469 u32 len = 0;
470 u32 cur, total_len;
471 char *name = NULL;
472 char *data = NULL;
473 int ret = 0;
475 key.objectid = inode;
476 key.type = BTRFS_XATTR_ITEM_KEY;
477 key.offset = 0;
479 path = btrfs_alloc_path();
480 if (!path)
481 return -ENOMEM;
483 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
484 if (ret < 0)
485 goto out;
487 leaf = path->nodes[0];
488 while (1) {
489 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
490 do {
491 ret = next_leaf(root, path);
492 if (ret < 0) {
493 error("searching for extended attributes: %d\n",
494 ret);
495 goto out;
496 } else if (ret) {
497 /* No more leaves to search */
498 ret = 0;
499 goto out;
501 leaf = path->nodes[0];
502 } while (!leaf);
503 continue;
506 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
507 if (key.type != BTRFS_XATTR_ITEM_KEY || key.objectid != inode)
508 break;
509 cur = 0;
510 total_len = btrfs_item_size_nr(leaf, path->slots[0]);
511 di = btrfs_item_ptr(leaf, path->slots[0],
512 struct btrfs_dir_item);
514 while (cur < total_len) {
515 len = btrfs_dir_name_len(leaf, di);
516 if (len > name_len) {
517 free(name);
518 name = (char *) malloc(len + 1);
519 if (!name) {
520 ret = -ENOMEM;
521 goto out;
524 read_extent_buffer(leaf, name,
525 (unsigned long)(di + 1), len);
526 name[len] = '\0';
527 name_len = len;
529 len = btrfs_dir_data_len(leaf, di);
530 if (len > data_len) {
531 free(data);
532 data = (char *) malloc(len);
533 if (!data) {
534 ret = -ENOMEM;
535 goto out;
538 read_extent_buffer(leaf, data,
539 (unsigned long)(di + 1) + name_len,
540 len);
541 data_len = len;
543 if (fsetxattr(fd, name, data, data_len, 0))
544 error("setting extended attribute %s on file %s: %s",
545 name, file_name, strerror(errno));
547 len = sizeof(*di) + name_len + data_len;
548 cur += len;
549 di = (struct btrfs_dir_item *)((char *)di + len);
551 path->slots[0]++;
553 ret = 0;
554 out:
555 btrfs_free_path(path);
556 free(name);
557 free(data);
559 return ret;
562 static int copy_metadata(struct btrfs_root *root, int fd,
563 struct btrfs_key *key)
565 struct btrfs_path *path;
566 struct btrfs_inode_item *inode_item;
567 int ret;
569 path = btrfs_alloc_path();
570 if (!path) {
571 error("not enough memory");
572 return -ENOMEM;
575 ret = btrfs_lookup_inode(NULL, root, path, key, 0);
576 if (ret == 0) {
577 struct btrfs_timespec *bts;
578 struct timespec times[2];
580 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
581 struct btrfs_inode_item);
583 ret = fchown(fd, btrfs_inode_uid(path->nodes[0], inode_item),
584 btrfs_inode_gid(path->nodes[0], inode_item));
585 if (ret) {
586 error("failed to change owner: %s", strerror(errno));
587 goto out;
590 ret = fchmod(fd, btrfs_inode_mode(path->nodes[0], inode_item));
591 if (ret) {
592 error("failed to change mode: %s", strerror(errno));
593 goto out;
596 bts = btrfs_inode_atime(inode_item);
597 times[0].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
598 times[0].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
600 bts = btrfs_inode_mtime(inode_item);
601 times[1].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
602 times[1].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
604 ret = futimens(fd, times);
605 if (ret) {
606 error("failed to set times: %s", strerror(errno));
607 goto out;
610 out:
611 btrfs_free_path(path);
612 return ret;
615 static int copy_file(struct btrfs_root *root, int fd, struct btrfs_key *key,
616 const char *file)
618 struct extent_buffer *leaf;
619 struct btrfs_path *path;
620 struct btrfs_file_extent_item *fi;
621 struct btrfs_inode_item *inode_item;
622 struct btrfs_timespec *bts;
623 struct btrfs_key found_key;
624 int ret;
625 int extent_type;
626 int compression;
627 int loops = 0;
628 u64 found_size = 0;
629 struct timespec times[2];
630 int times_ok = 0;
632 path = btrfs_alloc_path();
633 if (!path) {
634 error("not enough memory");
635 return -ENOMEM;
638 ret = btrfs_lookup_inode(NULL, root, path, key, 0);
639 if (ret == 0) {
640 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
641 struct btrfs_inode_item);
642 found_size = btrfs_inode_size(path->nodes[0], inode_item);
644 if (restore_metadata) {
646 * Change the ownership and mode now, set times when
647 * copyout is finished.
650 ret = fchown(fd, btrfs_inode_uid(path->nodes[0], inode_item),
651 btrfs_inode_gid(path->nodes[0], inode_item));
652 if (ret && !ignore_errors)
653 goto out;
655 ret = fchmod(fd, btrfs_inode_mode(path->nodes[0], inode_item));
656 if (ret && !ignore_errors)
657 goto out;
659 bts = btrfs_inode_atime(inode_item);
660 times[0].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
661 times[0].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
663 bts = btrfs_inode_mtime(inode_item);
664 times[1].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
665 times[1].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
666 times_ok = 1;
669 btrfs_release_path(path);
671 key->offset = 0;
672 key->type = BTRFS_EXTENT_DATA_KEY;
674 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
675 if (ret < 0) {
676 error("searching extent data returned %d", ret);
677 goto out;
680 leaf = path->nodes[0];
681 while (!leaf) {
682 ret = next_leaf(root, path);
683 if (ret < 0) {
684 error("cannot get next leaf: %d", ret);
685 goto out;
686 } else if (ret > 0) {
687 /* No more leaves to search */
688 ret = 0;
689 goto out;
691 leaf = path->nodes[0];
694 while (1) {
695 if (loops >= 0 && loops++ >= 1024) {
696 enum loop_response resp;
698 resp = ask_to_continue(file);
699 if (resp == LOOP_STOP)
700 break;
701 else if (resp == LOOP_CONTINUE)
702 loops = 0;
703 else if (resp == LOOP_DONTASK)
704 loops = -1;
706 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
707 do {
708 ret = next_leaf(root, path);
709 if (ret < 0) {
710 fprintf(stderr, "Error searching %d\n", ret);
711 goto out;
712 } else if (ret) {
713 /* No more leaves to search */
714 btrfs_free_path(path);
715 goto set_size;
717 leaf = path->nodes[0];
718 } while (!leaf);
719 continue;
721 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
722 if (found_key.objectid != key->objectid)
723 break;
724 if (found_key.type != key->type)
725 break;
726 fi = btrfs_item_ptr(leaf, path->slots[0],
727 struct btrfs_file_extent_item);
728 extent_type = btrfs_file_extent_type(leaf, fi);
729 compression = btrfs_file_extent_compression(leaf, fi);
730 if (compression >= BTRFS_COMPRESS_LAST) {
731 warning("compression type %d not supported",
732 compression);
733 ret = -1;
734 goto out;
737 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC)
738 goto next;
739 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
740 ret = copy_one_inline(root, fd, path, found_key.offset);
741 if (ret)
742 goto out;
743 } else if (extent_type == BTRFS_FILE_EXTENT_REG) {
744 ret = copy_one_extent(root, fd, leaf, fi,
745 found_key.offset);
746 if (ret)
747 goto out;
748 } else {
749 warning("weird extent type %d", extent_type);
751 next:
752 path->slots[0]++;
755 btrfs_free_path(path);
756 set_size:
757 if (found_size) {
758 ret = ftruncate(fd, (loff_t)found_size);
759 if (ret)
760 return ret;
762 if (get_xattrs) {
763 ret = set_file_xattrs(root, key->objectid, fd, file);
764 if (ret)
765 return ret;
767 if (restore_metadata && times_ok) {
768 ret = futimens(fd, times);
769 if (ret)
770 return ret;
772 return 0;
774 out:
775 btrfs_free_path(path);
776 return ret;
780 * returns:
781 * 0 if the file exists and should be skipped.
782 * 1 if the file does NOT exist
783 * 2 if the file exists but is OK to overwrite
785 static int overwrite_ok(const char * path)
787 static int warn = 0;
788 struct stat st;
789 int ret;
791 /* don't be fooled by symlinks */
792 ret = fstatat(-1, path_name, &st, AT_SYMLINK_NOFOLLOW);
794 if (!ret) {
795 if (overwrite)
796 return 2;
798 if (verbose || !warn)
799 printf("Skipping existing file"
800 " %s\n", path);
801 if (!warn)
802 printf("If you wish to overwrite use -o\n");
803 warn = 1;
804 return 0;
806 return 1;
809 static int copy_symlink(struct btrfs_root *root, struct btrfs_key *key,
810 const char *file)
812 struct btrfs_path *path;
813 struct extent_buffer *leaf;
814 struct btrfs_file_extent_item *extent_item;
815 struct btrfs_inode_item *inode_item;
816 u32 len;
817 u32 name_offset;
818 int ret;
819 struct btrfs_timespec *bts;
820 struct timespec times[2];
822 ret = overwrite_ok(path_name);
823 if (ret == 0)
824 return 0; /* skip this file */
826 /* symlink() can't overwrite, so unlink first */
827 if (ret == 2) {
828 ret = unlink(path_name);
829 if (ret) {
830 fprintf(stderr, "failed to unlink '%s' for overwrite\n",
831 path_name);
832 return ret;
836 key->type = BTRFS_EXTENT_DATA_KEY;
837 key->offset = 0;
839 path = btrfs_alloc_path();
840 if (!path)
841 return -ENOMEM;
843 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
844 if (ret < 0)
845 goto out;
847 leaf = path->nodes[0];
848 if (!leaf) {
849 fprintf(stderr, "Error getting leaf for symlink '%s'\n", file);
850 ret = -1;
851 goto out;
854 extent_item = btrfs_item_ptr(leaf, path->slots[0],
855 struct btrfs_file_extent_item);
857 len = btrfs_file_extent_inline_item_len(leaf,
858 btrfs_item_nr(path->slots[0]));
859 if (len >= PATH_MAX) {
860 fprintf(stderr, "Symlink '%s' target length %d is longer than PATH_MAX\n",
861 fs_name, len);
862 ret = -1;
863 goto out;
866 name_offset = (unsigned long) extent_item
867 + offsetof(struct btrfs_file_extent_item, disk_bytenr);
868 read_extent_buffer(leaf, symlink_target, name_offset, len);
870 symlink_target[len] = 0;
872 if (!dry_run) {
873 ret = symlink(symlink_target, path_name);
874 if (ret < 0) {
875 fprintf(stderr, "Failed to restore symlink '%s': %s\n",
876 path_name, strerror(errno));
877 goto out;
880 printf("SYMLINK: '%s' => '%s'\n", path_name, symlink_target);
882 ret = 0;
883 if (!restore_metadata)
884 goto out;
887 * Symlink metadata operates differently than files/directories, so do
888 * our own work here.
890 key->type = BTRFS_INODE_ITEM_KEY;
891 key->offset = 0;
893 btrfs_release_path(path);
895 ret = btrfs_lookup_inode(NULL, root, path, key, 0);
896 if (ret) {
897 fprintf(stderr, "Failed to lookup inode for '%s'\n", file);
898 goto out;
901 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
902 struct btrfs_inode_item);
904 ret = fchownat(-1, file, btrfs_inode_uid(path->nodes[0], inode_item),
905 btrfs_inode_gid(path->nodes[0], inode_item),
906 AT_SYMLINK_NOFOLLOW);
907 if (ret) {
908 fprintf(stderr, "Failed to change owner: %s\n",
909 strerror(errno));
910 goto out;
913 bts = btrfs_inode_atime(inode_item);
914 times[0].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
915 times[0].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
917 bts = btrfs_inode_mtime(inode_item);
918 times[1].tv_sec = btrfs_timespec_sec(path->nodes[0], bts);
919 times[1].tv_nsec = btrfs_timespec_nsec(path->nodes[0], bts);
921 ret = utimensat(-1, file, times, AT_SYMLINK_NOFOLLOW);
922 if (ret)
923 fprintf(stderr, "Failed to set times: %s\n", strerror(errno));
924 out:
925 btrfs_free_path(path);
926 return ret;
929 static int search_dir(struct btrfs_root *root, struct btrfs_key *key,
930 const char *output_rootdir, const char *in_dir,
931 const regex_t *mreg)
933 struct btrfs_path *path;
934 struct extent_buffer *leaf;
935 struct btrfs_dir_item *dir_item;
936 struct btrfs_key found_key, location;
937 char filename[BTRFS_NAME_LEN + 1];
938 unsigned long name_ptr;
939 int name_len;
940 int ret = 0;
941 int fd;
942 int loops = 0;
943 u8 type;
945 path = btrfs_alloc_path();
946 if (!path) {
947 fprintf(stderr, "Ran out of memory\n");
948 return -ENOMEM;
951 key->offset = 0;
952 key->type = BTRFS_DIR_INDEX_KEY;
954 ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
955 if (ret < 0) {
956 fprintf(stderr, "Error searching %d\n", ret);
957 goto out;
960 ret = 0;
962 leaf = path->nodes[0];
963 while (!leaf) {
964 if (verbose > 1)
965 printf("No leaf after search, looking for the next "
966 "leaf\n");
967 ret = next_leaf(root, path);
968 if (ret < 0) {
969 fprintf(stderr, "Error getting next leaf %d\n",
970 ret);
971 goto out;
972 } else if (ret > 0) {
973 /* No more leaves to search */
974 if (verbose)
975 printf("Reached the end of the tree looking "
976 "for the directory\n");
977 ret = 0;
978 goto out;
980 leaf = path->nodes[0];
983 while (leaf) {
984 if (loops++ >= 1024) {
985 printf("We have looped trying to restore files in %s "
986 "too many times to be making progress, "
987 "stopping\n", in_dir);
988 break;
991 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
992 do {
993 ret = next_leaf(root, path);
994 if (ret < 0) {
995 fprintf(stderr, "Error searching %d\n",
996 ret);
997 goto out;
998 } else if (ret > 0) {
999 /* No more leaves to search */
1000 if (verbose)
1001 printf("Reached the end of "
1002 "the tree searching the"
1003 " directory\n");
1004 ret = 0;
1005 goto out;
1007 leaf = path->nodes[0];
1008 } while (!leaf);
1009 continue;
1011 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
1012 if (found_key.objectid != key->objectid) {
1013 if (verbose > 1)
1014 printf("Found objectid=%Lu, key=%Lu\n",
1015 found_key.objectid, key->objectid);
1016 break;
1018 if (found_key.type != key->type) {
1019 if (verbose > 1)
1020 printf("Found type=%u, want=%u\n",
1021 found_key.type, key->type);
1022 break;
1024 dir_item = btrfs_item_ptr(leaf, path->slots[0],
1025 struct btrfs_dir_item);
1026 name_ptr = (unsigned long)(dir_item + 1);
1027 name_len = btrfs_dir_name_len(leaf, dir_item);
1028 read_extent_buffer(leaf, filename, name_ptr, name_len);
1029 filename[name_len] = '\0';
1030 type = btrfs_dir_type(leaf, dir_item);
1031 btrfs_dir_item_key_to_cpu(leaf, dir_item, &location);
1033 /* full path from root of btrfs being restored */
1034 snprintf(fs_name, PATH_MAX, "%s/%s", in_dir, filename);
1036 if (mreg && REG_NOMATCH == regexec(mreg, fs_name, 0, NULL, 0))
1037 goto next;
1039 /* full path from system root */
1040 snprintf(path_name, PATH_MAX, "%s%s", output_rootdir, fs_name);
1043 * Restore directories, files, symlinks and metadata.
1045 if (type == BTRFS_FT_REG_FILE) {
1046 if (!overwrite_ok(path_name))
1047 goto next;
1049 if (verbose)
1050 printf("Restoring %s\n", path_name);
1051 if (dry_run)
1052 goto next;
1053 fd = open(path_name, O_CREAT|O_WRONLY, 0644);
1054 if (fd < 0) {
1055 fprintf(stderr, "Error creating %s: %d\n",
1056 path_name, errno);
1057 if (ignore_errors)
1058 goto next;
1059 ret = -1;
1060 goto out;
1062 loops = 0;
1063 ret = copy_file(root, fd, &location, path_name);
1064 close(fd);
1065 if (ret) {
1066 fprintf(stderr, "Error copying data for %s\n",
1067 path_name);
1068 if (ignore_errors)
1069 goto next;
1070 goto out;
1072 } else if (type == BTRFS_FT_DIR) {
1073 struct btrfs_root *search_root = root;
1074 char *dir = strdup(fs_name);
1076 if (!dir) {
1077 fprintf(stderr, "Ran out of memory\n");
1078 ret = -ENOMEM;
1079 goto out;
1082 if (location.type == BTRFS_ROOT_ITEM_KEY) {
1084 * If we are a snapshot and this is the index
1085 * object to ourselves just skip it.
1087 if (location.objectid ==
1088 root->root_key.objectid) {
1089 free(dir);
1090 goto next;
1093 location.offset = (u64)-1;
1094 search_root = btrfs_read_fs_root(root->fs_info,
1095 &location);
1096 if (IS_ERR(search_root)) {
1097 free(dir);
1098 fprintf(stderr, "Error reading "
1099 "subvolume %s: %lu\n",
1100 path_name,
1101 PTR_ERR(search_root));
1102 if (ignore_errors)
1103 goto next;
1104 ret = PTR_ERR(search_root);
1105 goto out;
1109 * A subvolume will have a key.offset of 0, a
1110 * snapshot will have key.offset of a transid.
1112 if (search_root->root_key.offset != 0 &&
1113 get_snaps == 0) {
1114 free(dir);
1115 printf("Skipping snapshot %s\n",
1116 filename);
1117 goto next;
1119 location.objectid = BTRFS_FIRST_FREE_OBJECTID;
1122 if (verbose)
1123 printf("Restoring %s\n", path_name);
1125 errno = 0;
1126 if (dry_run)
1127 ret = 0;
1128 else
1129 ret = mkdir(path_name, 0755);
1130 if (ret && errno != EEXIST) {
1131 free(dir);
1132 fprintf(stderr, "Error mkdiring %s: %d\n",
1133 path_name, errno);
1134 if (ignore_errors)
1135 goto next;
1136 ret = -1;
1137 goto out;
1139 loops = 0;
1140 ret = search_dir(search_root, &location,
1141 output_rootdir, dir, mreg);
1142 free(dir);
1143 if (ret) {
1144 fprintf(stderr, "Error searching %s\n",
1145 path_name);
1146 if (ignore_errors)
1147 goto next;
1148 goto out;
1150 } else if (type == BTRFS_FT_SYMLINK) {
1151 if (restore_symlinks)
1152 ret = copy_symlink(root, &location, path_name);
1153 if (ret < 0) {
1154 if (ignore_errors)
1155 goto next;
1156 btrfs_free_path(path);
1157 return ret;
1160 next:
1161 path->slots[0]++;
1164 if (restore_metadata) {
1165 snprintf(path_name, PATH_MAX, "%s%s", output_rootdir, in_dir);
1166 fd = open(path_name, O_RDONLY);
1167 if (fd < 0) {
1168 fprintf(stderr, "ERROR: Failed to access %s to restore metadata\n",
1169 path_name);
1170 if (!ignore_errors) {
1171 ret = -1;
1172 goto out;
1174 } else {
1176 * Set owner/mode/time on the directory as well
1178 key->type = BTRFS_INODE_ITEM_KEY;
1179 ret = copy_metadata(root, fd, key);
1180 close(fd);
1181 if (ret && !ignore_errors)
1182 goto out;
1186 if (verbose)
1187 printf("Done searching %s\n", in_dir);
1188 out:
1189 btrfs_free_path(path);
1190 return ret;
1193 static int do_list_roots(struct btrfs_root *root)
1195 struct btrfs_key key;
1196 struct btrfs_key found_key;
1197 struct btrfs_disk_key disk_key;
1198 struct btrfs_path *path;
1199 struct extent_buffer *leaf;
1200 struct btrfs_root_item ri;
1201 unsigned long offset;
1202 int slot;
1203 int ret;
1205 root = root->fs_info->tree_root;
1206 path = btrfs_alloc_path();
1207 if (!path) {
1208 fprintf(stderr, "Failed to alloc path\n");
1209 return -ENOMEM;
1212 key.offset = 0;
1213 key.objectid = 0;
1214 key.type = BTRFS_ROOT_ITEM_KEY;
1216 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1217 if (ret < 0) {
1218 fprintf(stderr, "Failed to do search %d\n", ret);
1219 btrfs_free_path(path);
1220 return -1;
1223 leaf = path->nodes[0];
1225 while (1) {
1226 slot = path->slots[0];
1227 if (slot >= btrfs_header_nritems(leaf)) {
1228 ret = btrfs_next_leaf(root, path);
1229 if (ret)
1230 break;
1231 leaf = path->nodes[0];
1232 slot = path->slots[0];
1234 btrfs_item_key(leaf, &disk_key, slot);
1235 btrfs_disk_key_to_cpu(&found_key, &disk_key);
1236 if (btrfs_key_type(&found_key) != BTRFS_ROOT_ITEM_KEY) {
1237 path->slots[0]++;
1238 continue;
1241 offset = btrfs_item_ptr_offset(leaf, slot);
1242 read_extent_buffer(leaf, &ri, offset, sizeof(ri));
1243 printf(" tree ");
1244 btrfs_print_key(&disk_key);
1245 printf(" %Lu level %d\n", btrfs_root_bytenr(&ri),
1246 btrfs_root_level(&ri));
1247 path->slots[0]++;
1249 btrfs_free_path(path);
1251 return 0;
1254 static struct btrfs_root *open_fs(const char *dev, u64 root_location,
1255 int super_mirror, int list_roots)
1257 struct btrfs_fs_info *fs_info = NULL;
1258 struct btrfs_root *root = NULL;
1259 u64 bytenr;
1260 int i;
1262 for (i = super_mirror; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1263 bytenr = btrfs_sb_offset(i);
1264 fs_info = open_ctree_fs_info(dev, bytenr, root_location, 0,
1265 OPEN_CTREE_PARTIAL);
1266 if (fs_info)
1267 break;
1268 fprintf(stderr, "Could not open root, trying backup super\n");
1271 if (!fs_info)
1272 return NULL;
1275 * All we really need to succeed is reading the chunk tree, everything
1276 * else we can do by hand, since we only need to read the tree root and
1277 * the fs_root.
1279 if (!extent_buffer_uptodate(fs_info->tree_root->node)) {
1280 u64 generation;
1282 root = fs_info->tree_root;
1283 if (!root_location)
1284 root_location = btrfs_super_root(fs_info->super_copy);
1285 generation = btrfs_super_generation(fs_info->super_copy);
1286 root->node = read_tree_block(root, root_location,
1287 root->nodesize, generation);
1288 if (!extent_buffer_uptodate(root->node)) {
1289 fprintf(stderr, "Error opening tree root\n");
1290 close_ctree(root);
1291 return NULL;
1295 if (!list_roots && !fs_info->fs_root) {
1296 struct btrfs_key key;
1298 key.objectid = BTRFS_FS_TREE_OBJECTID;
1299 key.type = BTRFS_ROOT_ITEM_KEY;
1300 key.offset = (u64)-1;
1301 fs_info->fs_root = btrfs_read_fs_root_no_cache(fs_info, &key);
1302 if (IS_ERR(fs_info->fs_root)) {
1303 fprintf(stderr, "Couldn't read fs root: %ld\n",
1304 PTR_ERR(fs_info->fs_root));
1305 close_ctree(fs_info->tree_root);
1306 return NULL;
1310 if (list_roots && do_list_roots(fs_info->tree_root)) {
1311 close_ctree(fs_info->tree_root);
1312 return NULL;
1315 return fs_info->fs_root;
1318 static int find_first_dir(struct btrfs_root *root, u64 *objectid)
1320 struct btrfs_path *path;
1321 struct btrfs_key found_key;
1322 struct btrfs_key key;
1323 int ret = -1;
1324 int i;
1326 key.objectid = 0;
1327 key.type = BTRFS_DIR_INDEX_KEY;
1328 key.offset = 0;
1330 path = btrfs_alloc_path();
1331 if (!path) {
1332 fprintf(stderr, "Ran out of memory\n");
1333 return ret;
1336 ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1337 if (ret < 0) {
1338 fprintf(stderr, "Error searching %d\n", ret);
1339 goto out;
1342 if (!path->nodes[0]) {
1343 fprintf(stderr, "No leaf!\n");
1344 goto out;
1346 again:
1347 for (i = path->slots[0];
1348 i < btrfs_header_nritems(path->nodes[0]); i++) {
1349 btrfs_item_key_to_cpu(path->nodes[0], &found_key, i);
1350 if (found_key.type != key.type)
1351 continue;
1353 printf("Using objectid %Lu for first dir\n",
1354 found_key.objectid);
1355 *objectid = found_key.objectid;
1356 ret = 0;
1357 goto out;
1359 do {
1360 ret = next_leaf(root, path);
1361 if (ret < 0) {
1362 fprintf(stderr, "Error getting next leaf %d\n",
1363 ret);
1364 goto out;
1365 } else if (ret > 0) {
1366 fprintf(stderr, "No more leaves\n");
1367 goto out;
1369 } while (!path->nodes[0]);
1370 if (path->nodes[0])
1371 goto again;
1372 printf("Couldn't find a dir index item\n");
1373 out:
1374 btrfs_free_path(path);
1375 return ret;
1378 const char * const cmd_restore_usage[] = {
1379 "btrfs restore [options] <device> <path> | -l <device>",
1380 "Try to restore files from a damaged filesystem (unmounted)",
1382 "-s|--snapshots get snapshots",
1383 "-x|--xattr get extended attributes",
1384 "-m|--metadata restore owner, mode and times",
1385 "-S|--symlinks restore symbolic links",
1386 "-v|--verbose verbose",
1387 "-i|--ignore-errors ignore errors",
1388 "-o|--overwrite overwrite",
1389 "-t <bytenr> tree location",
1390 "-f <bytenr> filesystem location",
1391 "-u|--super <mirror> super mirror",
1392 "-r|--root <rootid> root objectid",
1393 "-d find dir",
1394 "-l|--list-roots list tree roots",
1395 "-D|--dry-run dry run (only list files that would be recovered)",
1396 "--path-regex <regex>",
1397 " restore only filenames matching regex,",
1398 " you have to use following syntax (possibly quoted):",
1399 " ^/(|home(|/username(|/Desktop(|/.*))))$",
1400 "-c ignore case (--path-regex only)",
1401 NULL
1404 int cmd_restore(int argc, char **argv)
1406 struct btrfs_root *root;
1407 struct btrfs_key key;
1408 char dir_name[PATH_MAX];
1409 u64 tree_location = 0;
1410 u64 fs_location = 0;
1411 u64 root_objectid = 0;
1412 int len;
1413 int ret;
1414 int super_mirror = 0;
1415 int find_dir = 0;
1416 int list_roots = 0;
1417 const char *match_regstr = NULL;
1418 int match_cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
1419 regex_t match_reg, *mreg = NULL;
1420 char reg_err[256];
1422 while (1) {
1423 int opt;
1424 static const struct option long_options[] = {
1425 { "path-regex", required_argument, NULL, 256},
1426 { "dry-run", no_argument, NULL, 'D'},
1427 { "metadata", no_argument, NULL, 'm'},
1428 { "symlinks", no_argument, NULL, 'S'},
1429 { "snapshots", no_argument, NULL, 's'},
1430 { "xattr", no_argument, NULL, 'x'},
1431 { "verbose", no_argument, NULL, 'v'},
1432 { "ignore-errors", no_argument, NULL, 'i'},
1433 { "overwrite", no_argument, NULL, 'o'},
1434 { "super", required_argument, NULL, 'u'},
1435 { "root", required_argument, NULL, 'r'},
1436 { "list-roots", no_argument, NULL, 'l'},
1437 { NULL, 0, NULL, 0}
1440 opt = getopt_long(argc, argv, "sSxviot:u:dmf:r:lDc", long_options,
1441 NULL);
1442 if (opt < 0)
1443 break;
1445 switch (opt) {
1446 case 's':
1447 get_snaps = 1;
1448 break;
1449 case 'v':
1450 verbose++;
1451 break;
1452 case 'i':
1453 ignore_errors = 1;
1454 break;
1455 case 'o':
1456 overwrite = 1;
1457 break;
1458 case 't':
1459 tree_location = arg_strtou64(optarg);
1460 break;
1461 case 'f':
1462 fs_location = arg_strtou64(optarg);
1463 break;
1464 case 'u':
1465 super_mirror = arg_strtou64(optarg);
1466 if (super_mirror >= BTRFS_SUPER_MIRROR_MAX) {
1467 fprintf(stderr, "Super mirror not "
1468 "valid\n");
1469 exit(1);
1471 break;
1472 case 'd':
1473 find_dir = 1;
1474 break;
1475 case 'r':
1476 root_objectid = arg_strtou64(optarg);
1477 if (!is_fstree(root_objectid)) {
1478 fprintf(stderr, "objectid %llu is not a valid fs/file tree\n",
1479 root_objectid);
1480 exit(1);
1482 break;
1483 case 'l':
1484 list_roots = 1;
1485 break;
1486 case 'm':
1487 restore_metadata = 1;
1488 break;
1489 case 'S':
1490 restore_symlinks = 1;
1491 break;
1492 case 'D':
1493 dry_run = 1;
1494 break;
1495 case 'c':
1496 match_cflags |= REG_ICASE;
1497 break;
1498 /* long option without single letter alternative */
1499 case 256:
1500 match_regstr = optarg;
1501 break;
1502 case 'x':
1503 get_xattrs = 1;
1504 break;
1505 default:
1506 usage(cmd_restore_usage);
1510 if (!list_roots && check_argc_min(argc - optind, 2))
1511 usage(cmd_restore_usage);
1512 else if (list_roots && check_argc_min(argc - optind, 1))
1513 usage(cmd_restore_usage);
1515 if (fs_location && root_objectid) {
1516 fprintf(stderr, "don't use -f and -r at the same time.\n");
1517 return 1;
1520 if ((ret = check_mounted(argv[optind])) < 0) {
1521 fprintf(stderr, "Could not check mount status: %s\n",
1522 strerror(-ret));
1523 return 1;
1524 } else if (ret) {
1525 fprintf(stderr, "%s is currently mounted. Aborting.\n", argv[optind]);
1526 return 1;
1529 root = open_fs(argv[optind], tree_location, super_mirror, list_roots);
1530 if (root == NULL)
1531 return 1;
1533 if (list_roots)
1534 goto out;
1536 if (fs_location != 0) {
1537 free_extent_buffer(root->node);
1538 root->node = read_tree_block(root, fs_location, root->nodesize, 0);
1539 if (!extent_buffer_uptodate(root->node)) {
1540 fprintf(stderr, "Failed to read fs location\n");
1541 ret = 1;
1542 goto out;
1546 memset(path_name, 0, PATH_MAX);
1548 if (strlen(argv[optind + 1]) >= PATH_MAX) {
1549 fprintf(stderr, "ERROR: path too long\n");
1550 ret = 1;
1551 goto out;
1553 strncpy(dir_name, argv[optind + 1], sizeof dir_name);
1554 dir_name[sizeof dir_name - 1] = 0;
1556 /* Strip the trailing / on the dir name */
1557 len = strlen(dir_name);
1558 while (len && dir_name[--len] == '/') {
1559 dir_name[len] = '\0';
1562 if (root_objectid != 0) {
1563 struct btrfs_root *orig_root = root;
1565 key.objectid = root_objectid;
1566 key.type = BTRFS_ROOT_ITEM_KEY;
1567 key.offset = (u64)-1;
1568 root = btrfs_read_fs_root(orig_root->fs_info, &key);
1569 if (IS_ERR(root)) {
1570 fprintf(stderr, "fail to read root %llu: %s\n",
1571 root_objectid, strerror(-PTR_ERR(root)));
1572 root = orig_root;
1573 ret = 1;
1574 goto out;
1576 key.type = 0;
1577 key.offset = 0;
1580 if (find_dir) {
1581 ret = find_first_dir(root, &key.objectid);
1582 if (ret)
1583 goto out;
1584 } else {
1585 key.objectid = BTRFS_FIRST_FREE_OBJECTID;
1588 if (match_regstr) {
1589 ret = regcomp(&match_reg, match_regstr, match_cflags);
1590 if (ret) {
1591 regerror(ret, &match_reg, reg_err, sizeof(reg_err));
1592 fprintf(stderr, "Regex compile failed: %s\n", reg_err);
1593 goto out;
1595 mreg = &match_reg;
1598 if (dry_run)
1599 printf("This is a dry-run, no files are going to be restored\n");
1601 ret = search_dir(root, &key, dir_name, "", mreg);
1603 out:
1604 if (mreg)
1605 regfree(mreg);
1606 close_ctree(root);
1607 return !!ret;