cmds-restore.c

   1 /*
   2  * Copyright (C) 2011 Red Hat.  All rights reserved.
   3  *
   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.
   7  *
   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.
  12  *
  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.
  17  */
  18
  19 #define _XOPEN_SOURCE 500
  20 #define _GNU_SOURCE 1
  21
  22 #include "kerncompat.h"
  23
  24 #include <ctype.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <unistd.h>
  28 #include <fcntl.h>
  29 #include <sys/stat.h>
  30 #include <sys/types.h>
  31 #include <lzo/lzoconf.h>
  32 #include <lzo/lzo1x.h>
  33 #include <zlib.h>
  34 #include <regex.h>
  35
  36 #include "ctree.h"
  37 #include "disk-io.h"
  38 #include "print-tree.h"
  39 #include "transaction.h"
  40 #include "list.h"
  41 #include "version.h"
  42 #include "volumes.h"
  43 #include "utils.h"
  44 #include "commands.h"
  45
  46 static char fs_name[4096];
  47 static char path_name[4096];
  48 static int get_snaps = 0;
  49 static int verbose = 0;
  50 static int ignore_errors = 0;
  51 static int overwrite = 0;
  52
  53 #define LZO_LEN 4
  54 #define PAGE_CACHE_SIZE 4096
  55 #define lzo1x_worst_compress(x) ((x) + ((x) / 16) + 64 + 3)
  56
  57 static int decompress_zlib(char *inbuf, char *outbuf, u64 compress_len,
  58                            u64 decompress_len)
  59 {
  60         z_stream strm;
  61         int ret;
  62
  63         memset(&strm, 0, sizeof(strm));
  64         ret = inflateInit(&strm);
  65         if (ret != Z_OK) {
  66                 fprintf(stderr, "inflate init returnd %d\n", ret);
  67                 return -1;
  68         }
  69
  70         strm.avail_in = compress_len;
  71         strm.next_in = (unsigned char *)inbuf;
  72         strm.avail_out = decompress_len;
  73         strm.next_out = (unsigned char *)outbuf;
  74         ret = inflate(&strm, Z_NO_FLUSH);
  75         if (ret != Z_STREAM_END) {
  76                 (void)inflateEnd(&strm);
  77                 fprintf(stderr, "failed to inflate: %d\n", ret);
  78                 return -1;
  79         }
  80
  81         (void)inflateEnd(&strm);
  82         return 0;
  83 }
  84 static inline size_t read_compress_length(unsigned char *buf)
  85 {
  86         __le32 dlen;
  87         memcpy(&dlen, buf, LZO_LEN);
  88         return le32_to_cpu(dlen);
  89 }
  90
  91 static int decompress_lzo(unsigned char *inbuf, char *outbuf, u64 compress_len,
  92                           u64 *decompress_len)
  93 {
  94         size_t new_len;
  95         size_t in_len;
  96         size_t out_len = 0;
  97         size_t tot_len;
  98         size_t tot_in;
  99         int ret;
 100
 101         ret = lzo_init();
 102         if (ret != LZO_E_OK) {
 103                 fprintf(stderr, "lzo init returned %d\n", ret);
 104                 return -1;
 105         }
 106
 107         tot_len = read_compress_length(inbuf);
 108         inbuf += LZO_LEN;
 109         tot_in = LZO_LEN;
 110
 111         while (tot_in < tot_len) {
 112                 in_len = read_compress_length(inbuf);
 113                 inbuf += LZO_LEN;
 114                 tot_in += LZO_LEN;
 115
 116                 new_len = lzo1x_worst_compress(PAGE_CACHE_SIZE);
 117                 ret = lzo1x_decompress_safe((const unsigned char *)inbuf, in_len,
 118                                             (unsigned char *)outbuf,
 119                                             (void *)&new_len, NULL);
 120                 if (ret != LZO_E_OK) {
 121                         fprintf(stderr, "failed to inflate: %d\n", ret);
 122                         return -1;
 123                 }
 124                 out_len += new_len;
 125                 outbuf += new_len;
 126                 inbuf += in_len;
 127                 tot_in += in_len;
 128         }
 129
 130         *decompress_len = out_len;
 131
 132         return 0;
 133 }
 134
 135 static int decompress(char *inbuf, char *outbuf, u64 compress_len,
 136                       u64 *decompress_len, int compress)
 137 {
 138         switch (compress) {
 139         case BTRFS_COMPRESS_ZLIB:
 140                 return decompress_zlib(inbuf, outbuf, compress_len,
 141                                        *decompress_len);
 142         case BTRFS_COMPRESS_LZO:
 143                 return decompress_lzo((unsigned char *)inbuf, outbuf, compress_len,
 144                                       decompress_len);
 145         default:
 146                 break;
 147         }
 148
 149         fprintf(stderr, "invalid compression type: %d\n", compress);
 150         return -1;
 151 }
 152
 153 int next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 154 {
 155         int slot;
 156         int level = 1;
 157         int offset = 1;
 158         struct extent_buffer *c;
 159         struct extent_buffer *next = NULL;
 160
 161 again:
 162         for (; level < BTRFS_MAX_LEVEL; level++) {
 163                 if (path->nodes[level])
 164                         break;
 165         }
 166
 167         if (level == BTRFS_MAX_LEVEL)
 168                 return 1;
 169
 170         slot = path->slots[level] + 1;
 171
 172         while(level < BTRFS_MAX_LEVEL) {
 173                 if (!path->nodes[level])
 174                         return 1;
 175
 176                 slot = path->slots[level] + offset;
 177                 c = path->nodes[level];
 178                 if (slot >= btrfs_header_nritems(c)) {
 179                         level++;
 180                         if (level == BTRFS_MAX_LEVEL)
 181                                 return 1;
 182                         continue;
 183                 }
 184
 185                 if (path->reada)
 186                         reada_for_search(root, path, level, slot, 0);
 187
 188                 next = read_node_slot(root, c, slot);
 189                 if (next)
 190                         break;
 191                 offset++;
 192         }
 193         path->slots[level] = slot;
 194         while(1) {
 195                 level--;
 196                 c = path->nodes[level];
 197                 free_extent_buffer(c);
 198                 path->nodes[level] = next;
 199                 path->slots[level] = 0;
 200                 if (!level)
 201                         break;
 202                 if (path->reada)
 203                         reada_for_search(root, path, level, 0, 0);
 204                 next = read_node_slot(root, next, 0);
 205                 if (!next)
 206                         goto again;
 207         }
 208         return 0;
 209 }
 210
 211 static int copy_one_inline(int fd, struct btrfs_path *path, u64 pos)
 212 {
 213         struct extent_buffer *leaf = path->nodes[0];
 214         struct btrfs_file_extent_item *fi;
 215         char buf[4096];
 216         char *outbuf;
 217         u64 ram_size;
 218         ssize_t done;
 219         unsigned long ptr;
 220         int ret;
 221         int len;
 222         int compress;
 223
 224         fi = btrfs_item_ptr(leaf, path->slots[0],
 225                             struct btrfs_file_extent_item);
 226         ptr = btrfs_file_extent_inline_start(fi);
 227         len = btrfs_file_extent_inline_item_len(leaf,
 228                                         btrfs_item_nr(leaf, path->slots[0]));
 229         read_extent_buffer(leaf, buf, ptr, len);
 230
 231         compress = btrfs_file_extent_compression(leaf, fi);
 232         if (compress == BTRFS_COMPRESS_NONE) {
 233                 done = pwrite(fd, buf, len, pos);
 234                 if (done < len) {
 235                         fprintf(stderr, "Short inline write, wanted %d, did "
 236                                 "%zd: %d\n", len, done, errno);
 237                         return -1;
 238                 }
 239                 return 0;
 240         }
 241
 242         ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
 243         outbuf = malloc(ram_size);
 244         if (!outbuf) {
 245                 fprintf(stderr, "No memory\n");
 246                 return -1;
 247         }
 248
 249         ret = decompress(buf, outbuf, len, &ram_size, compress);
 250         if (ret) {
 251                 free(outbuf);
 252                 return ret;
 253         }
 254
 255         done = pwrite(fd, outbuf, ram_size, pos);
 256         free(outbuf);
 257         if (done < ram_size) {
 258                 fprintf(stderr, "Short compressed inline write, wanted %Lu, "
 259                         "did %zd: %d\n", ram_size, done, errno);
 260                 return -1;
 261         }
 262
 263         return 0;
 264 }
 265
 266 static int copy_one_extent(struct btrfs_root *root, int fd,
 267                            struct extent_buffer *leaf,
 268                            struct btrfs_file_extent_item *fi, u64 pos)
 269 {
 270         struct btrfs_multi_bio *multi = NULL;
 271         struct btrfs_device *device;
 272         char *inbuf, *outbuf = NULL;
 273         ssize_t done, total = 0;
 274         u64 bytenr;
 275         u64 ram_size;
 276         u64 disk_size;
 277         u64 length;
 278         u64 size_left;
 279         u64 dev_bytenr;
 280         u64 offset;
 281         u64 count = 0;
 282         int compress;
 283         int ret;
 284         int dev_fd;
 285         int mirror_num = 1;
 286         int num_copies;
 287
 288         compress = btrfs_file_extent_compression(leaf, fi);
 289         bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
 290         disk_size = btrfs_file_extent_disk_num_bytes(leaf, fi);
 291         ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
 292         offset = btrfs_file_extent_offset(leaf, fi);
 293         size_left = disk_size;
 294
 295         if (offset)
 296                 printf("offset is %Lu\n", offset);
 297         /* we found a hole */
 298         if (disk_size == 0)
 299                 return 0;
 300
 301         inbuf = malloc(disk_size);
 302         if (!inbuf) {
 303                 fprintf(stderr, "No memory\n");
 304                 return -1;
 305         }
 306
 307         if (compress != BTRFS_COMPRESS_NONE) {
 308                 outbuf = malloc(ram_size);
 309                 if (!outbuf) {
 310                         fprintf(stderr, "No memory\n");
 311                         free(inbuf);
 312                         return -1;
 313                 }
 314         }
 315 again:
 316         length = size_left;
 317         ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
 318                               bytenr, &length, &multi, mirror_num, NULL);
 319         if (ret) {
 320                 fprintf(stderr, "Error mapping block %d\n", ret);
 321                 goto out;
 322         }
 323         device = multi->stripes[0].dev;
 324         dev_fd = device->fd;
 325         device->total_ios++;
 326         dev_bytenr = multi->stripes[0].physical;
 327         kfree(multi);
 328
 329         if (size_left < length)
 330                 length = size_left;
 331
 332         done = pread(dev_fd, inbuf+count, length, dev_bytenr);
 333         /* Need both checks, or we miss negative values due to u64 conversion */
 334         if (done < 0 || done < length) {
 335                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 336                                               bytenr, length);
 337                 mirror_num++;
 338                 /* mirror_num is 1-indexed, so num_copies is a valid mirror. */
 339                 if (mirror_num > num_copies) {
 340                         ret = -1;
 341                         fprintf(stderr, "Exhausted mirrors trying to read\n");
 342                         goto out;
 343                 }
 344                 fprintf(stderr, "Trying another mirror\n");
 345                 goto again;
 346         }
 347
 348         mirror_num = 1;
 349         size_left -= length;
 350         count += length;
 351         bytenr += length;
 352         if (size_left)
 353                 goto again;
 354
 355         if (compress == BTRFS_COMPRESS_NONE) {
 356                 while (total < ram_size) {
 357                         done = pwrite(fd, inbuf+total, ram_size-total,
 358                                       pos+total);
 359                         if (done < 0) {
 360                                 ret = -1;
 361                                 fprintf(stderr, "Error writing: %d %s\n", errno, strerror(errno));
 362                                 goto out;
 363                         }
 364                         total += done;
 365                 }
 366                 ret = 0;
 367                 goto out;
 368         }
 369
 370         ret = decompress(inbuf, outbuf, disk_size, &ram_size, compress);
 371         if (ret) {
 372                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 373                                               bytenr, length);
 374                 mirror_num++;
 375                 if (mirror_num >= num_copies) {
 376                         ret = -1;
 377                         goto out;
 378                 }
 379                 fprintf(stderr, "Trying another mirror\n");
 380                 goto again;
 381         }
 382
 383         while (total < ram_size) {
 384                 done = pwrite(fd, outbuf+total, ram_size-total, pos+total);
 385                 if (done < 0) {
 386                         ret = -1;
 387                         goto out;
 388                 }
 389                 total += done;
 390         }
 391 out:
 392         free(inbuf);
 393         free(outbuf);
 394         return ret;
 395 }
 396
 397 static int ask_to_continue(const char *file)
 398 {
 399         char buf[2];
 400         char *ret;
 401
 402         printf("We seem to be looping a lot on %s, do you want to keep going "
 403                "on ? (y/N): ", file);
 404 again:
 405         ret = fgets(buf, 2, stdin);
 406         if (*ret == '\n' || tolower(*ret) == 'n')
 407                 return 1;
 408         if (tolower(*ret) != 'y') {
 409                 printf("Please enter either 'y' or 'n': ");
 410                 goto again;
 411         }
 412
 413         return 0;
 414 }
 415
 416
 417 static int copy_file(struct btrfs_root *root, int fd, struct btrfs_key *key,
 418                      const char *file)
 419 {
 420         struct extent_buffer *leaf;
 421         struct btrfs_path *path;
 422         struct btrfs_file_extent_item *fi;
 423         struct btrfs_inode_item *inode_item;
 424         struct btrfs_key found_key;
 425         int ret;
 426         int extent_type;
 427         int compression;
 428         int loops = 0;
 429         u64 found_size = 0;
 430
 431         path = btrfs_alloc_path();
 432         if (!path) {
 433                 fprintf(stderr, "Ran out of memory\n");
 434                 return -1;
 435         }
 436         path->skip_locking = 1;
 437
 438         ret = btrfs_lookup_inode(NULL, root, path, key, 0);
 439         if (ret == 0) {
 440                 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
 441                                     struct btrfs_inode_item);
 442                 found_size = btrfs_inode_size(path->nodes[0], inode_item);
 443         }
 444         btrfs_release_path(root, path);
 445
 446         key->offset = 0;
 447         key->type = BTRFS_EXTENT_DATA_KEY;
 448
 449         ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
 450         if (ret < 0) {
 451                 fprintf(stderr, "Error searching %d\n", ret);
 452                 btrfs_free_path(path);
 453                 return ret;
 454         }
 455
 456         leaf = path->nodes[0];
 457         while (!leaf) {
 458                 ret = next_leaf(root, path);
 459                 if (ret < 0) {
 460                         fprintf(stderr, "Error getting next leaf %d\n",
 461                                 ret);
 462                         btrfs_free_path(path);
 463                         return ret;
 464                 } else if (ret > 0) {
 465                         /* No more leaves to search */
 466                         btrfs_free_path(path);
 467                         return 0;
 468                 }
 469                 leaf = path->nodes[0];
 470         }
 471
 472         while (1) {
 473                 if (loops++ >= 1024) {
 474                         ret = ask_to_continue(file);
 475                         if (ret)
 476                                 break;
 477                         loops = 0;
 478                 }
 479                 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
 480                         do {
 481                                 ret = next_leaf(root, path);
 482                                 if (ret < 0) {
 483                                         fprintf(stderr, "Error searching %d\n", ret);
 484                                         btrfs_free_path(path);
 485                                         return ret;
 486                                 } else if (ret) {
 487                                         /* No more leaves to search */
 488                                         btrfs_free_path(path);
 489                                         goto set_size;
 490                                 }
 491                                 leaf = path->nodes[0];
 492                         } while (!leaf);
 493                         continue;
 494                 }
 495                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 496                 if (found_key.objectid != key->objectid)
 497                         break;
 498                 if (found_key.type != key->type)
 499                         break;
 500                 fi = btrfs_item_ptr(leaf, path->slots[0],
 501                                     struct btrfs_file_extent_item);
 502                 extent_type = btrfs_file_extent_type(leaf, fi);
 503                 compression = btrfs_file_extent_compression(leaf, fi);
 504                 if (compression >= BTRFS_COMPRESS_LAST) {
 505                         fprintf(stderr, "Don't support compression yet %d\n",
 506                                 compression);
 507                         btrfs_free_path(path);
 508                         return -1;
 509                 }
 510
 511                 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC)
 512                         goto next;
 513                 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
 514                         ret = copy_one_inline(fd, path, found_key.offset);
 515                         if (ret) {
 516                                 btrfs_free_path(path);
 517                                 return -1;
 518                         }
 519                 } else if (extent_type == BTRFS_FILE_EXTENT_REG) {
 520                         ret = copy_one_extent(root, fd, leaf, fi,
 521                                               found_key.offset);
 522                         if (ret) {
 523                                 btrfs_free_path(path);
 524                                 return ret;
 525                         }
 526                 } else {
 527                         printf("Weird extent type %d\n", extent_type);
 528                 }
 529 next:
 530                 path->slots[0]++;
 531         }
 532
 533         btrfs_free_path(path);
 534 set_size:
 535         if (found_size) {
 536                 ret = ftruncate(fd, (loff_t)found_size);
 537                 if (ret)
 538                         return ret;
 539         }
 540         return 0;
 541 }
 542
 543 static int search_dir(struct btrfs_root *root, struct btrfs_key *key,
 544                       const char *output_rootdir, const char *dir,
 545                       const regex_t *mreg)
 546 {
 547         struct btrfs_path *path;
 548         struct extent_buffer *leaf;
 549         struct btrfs_dir_item *dir_item;
 550         struct btrfs_key found_key, location;
 551         char filename[BTRFS_NAME_LEN + 1];
 552         unsigned long name_ptr;
 553         int name_len;
 554         int ret;
 555         int fd;
 556         int loops = 0;
 557         u8 type;
 558
 559         path = btrfs_alloc_path();
 560         if (!path) {
 561                 fprintf(stderr, "Ran out of memory\n");
 562                 return -1;
 563         }
 564         path->skip_locking = 1;
 565
 566         key->offset = 0;
 567         key->type = BTRFS_DIR_INDEX_KEY;
 568
 569         ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
 570         if (ret < 0) {
 571                 fprintf(stderr, "Error searching %d\n", ret);
 572                 btrfs_free_path(path);
 573                 return ret;
 574         }
 575
 576         leaf = path->nodes[0];
 577         while (!leaf) {
 578                 if (verbose > 1)
 579                         printf("No leaf after search, looking for the next "
 580                                "leaf\n");
 581                 ret = next_leaf(root, path);
 582                 if (ret < 0) {
 583                         fprintf(stderr, "Error getting next leaf %d\n",
 584                                 ret);
 585                         btrfs_free_path(path);
 586                         return ret;
 587                 } else if (ret > 0) {
 588                         /* No more leaves to search */
 589                         if (verbose)
 590                                 printf("Reached the end of the tree looking "
 591                                        "for the directory\n");
 592                         btrfs_free_path(path);
 593                         return 0;
 594                 }
 595                 leaf = path->nodes[0];
 596         }
 597
 598         while (leaf) {
 599                 if (loops++ >= 1024) {
 600                         printf("We have looped trying to restore files in %s "
 601                                "too many times to be making progress, "
 602                                "stopping\n", dir);
 603                         break;
 604                 }
 605
 606                 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
 607                         do {
 608                                 ret = next_leaf(root, path);
 609                                 if (ret < 0) {
 610                                         fprintf(stderr, "Error searching %d\n",
 611                                                 ret);
 612                                         btrfs_free_path(path);
 613                                         return ret;
 614                                 } else if (ret > 0) {
 615                                         /* No more leaves to search */
 616                                         if (verbose)
 617                                                 printf("Reached the end of "
 618                                                        "the tree searching the"
 619                                                        " directory\n");
 620                                         btrfs_free_path(path);
 621                                         return 0;
 622                                 }
 623                                 leaf = path->nodes[0];
 624                         } while (!leaf);
 625                         continue;
 626                 }
 627                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 628                 if (found_key.objectid != key->objectid) {
 629                         if (verbose > 1)
 630                                 printf("Found objectid=%Lu, key=%Lu\n",
 631                                        found_key.objectid, key->objectid);
 632                         break;
 633                 }
 634                 if (found_key.type != key->type) {
 635                         if (verbose > 1)
 636                                 printf("Found type=%u, want=%u\n",
 637                                        found_key.type, key->type);
 638                         break;
 639                 }
 640                 dir_item = btrfs_item_ptr(leaf, path->slots[0],
 641                                           struct btrfs_dir_item);
 642                 name_ptr = (unsigned long)(dir_item + 1);
 643                 name_len = btrfs_dir_name_len(leaf, dir_item);
 644                 read_extent_buffer(leaf, filename, name_ptr, name_len);
 645                 filename[name_len] = '\0';
 646                 type = btrfs_dir_type(leaf, dir_item);
 647                 btrfs_dir_item_key_to_cpu(leaf, dir_item, &location);
 648
 649                 /* full path from root of btrfs being restored */
 650                 snprintf(fs_name, 4096, "%s/%s", dir, filename);
 651
 652                 if (mreg && REG_NOMATCH == regexec(mreg, fs_name, 0, NULL, 0))
 653                         goto next;
 654
 655                 /* full path from system root */
 656                 snprintf(path_name, 4096, "%s%s", output_rootdir, fs_name);
 657
 658                 /*
 659                  * At this point we're only going to restore directories and
 660                  * files, no symlinks or anything else.
 661                  */
 662                 if (type == BTRFS_FT_REG_FILE) {
 663                         if (!overwrite) {
 664                                 static int warn = 0;
 665                                 struct stat st;
 666
 667                                 ret = stat(path_name, &st);
 668                                 if (!ret) {
 669                                         loops = 0;
 670                                         if (verbose || !warn)
 671                                                 printf("Skipping existing file"
 672                                                        " %s\n", path_name);
 673                                         if (warn)
 674                                                 goto next;
 675                                         printf("If you wish to overwrite use "
 676                                                "the -o option to overwrite\n");
 677                                         warn = 1;
 678                                         goto next;
 679                                 }
 680                                 ret = 0;
 681                         }
 682                         if (verbose)
 683                                 printf("Restoring %s\n", path_name);
 684                         fd = open(path_name, O_CREAT|O_WRONLY, 0644);
 685                         if (fd < 0) {
 686                                 fprintf(stderr, "Error creating %s: %d\n",
 687                                         path_name, errno);
 688                                 if (ignore_errors)
 689                                         goto next;
 690                                 btrfs_free_path(path);
 691                                 return -1;
 692                         }
 693                         loops = 0;
 694                         ret = copy_file(root, fd, &location, path_name);
 695                         close(fd);
 696                         if (ret) {
 697                                 if (ignore_errors)
 698                                         goto next;
 699                                 btrfs_free_path(path);
 700                                 return ret;
 701                         }
 702                 } else if (type == BTRFS_FT_DIR) {
 703                         struct btrfs_root *search_root = root;
 704                         char *dir = strdup(fs_name);
 705
 706                         if (!dir) {
 707                                 fprintf(stderr, "Ran out of memory\n");
 708                                 btrfs_free_path(path);
 709                                 return -1;
 710                         }
 711
 712                         if (location.type == BTRFS_ROOT_ITEM_KEY) {
 713                                 /*
 714                                  * If we are a snapshot and this is the index
 715                                  * object to ourselves just skip it.
 716                                  */
 717                                 if (location.objectid ==
 718                                     root->root_key.objectid) {
 719                                         free(dir);
 720                                         goto next;
 721                                 }
 722
 723                                 location.offset = (u64)-1;
 724                                 search_root = btrfs_read_fs_root(root->fs_info,
 725                                                                  &location);
 726                                 if (IS_ERR(search_root)) {
 727                                         free(dir);
 728                                         fprintf(stderr, "Error reading "
 729                                                 "subvolume %s: %lu\n",
 730                                                 path_name,
 731                                                 PTR_ERR(search_root));
 732                                         if (ignore_errors)
 733                                                 goto next;
 734                                         btrfs_free_path(path);
 735                                         return PTR_ERR(search_root);
 736                                 }
 737
 738                                 /*
 739                                  * A subvolume will have a key.offset of 0, a
 740                                  * snapshot will have key.offset of a transid.
 741                                  */
 742                                 if (search_root->root_key.offset != 0 &&
 743                                     get_snaps == 0) {
 744                                         free(dir);
 745                                         printf("Skipping snapshot %s\n",
 746                                                filename);
 747                                         goto next;
 748                                 }
 749                                 location.objectid = BTRFS_FIRST_FREE_OBJECTID;
 750                         }
 751
 752                         if (verbose)
 753                                 printf("Restoring %s\n", path_name);
 754
 755                         errno = 0;
 756                         ret = mkdir(path_name, 0755);
 757                         if (ret && errno != EEXIST) {
 758                                 free(dir);
 759                                 fprintf(stderr, "Error mkdiring %s: %d\n",
 760                                         path_name, errno);
 761                                 if (ignore_errors)
 762                                         goto next;
 763                                 btrfs_free_path(path);
 764                                 return -1;
 765                         }
 766                         loops = 0;
 767                         ret = search_dir(search_root, &location,
 768                                          output_rootdir, dir, mreg);
 769                         free(dir);
 770                         if (ret) {
 771                                 if (ignore_errors)
 772                                         goto next;
 773                                 btrfs_free_path(path);
 774                                 return ret;
 775                         }
 776                 }
 777 next:
 778                 path->slots[0]++;
 779         }
 780
 781         if (verbose)
 782                 printf("Done searching %s\n", dir);
 783         btrfs_free_path(path);
 784         return 0;
 785 }
 786
 787 static int do_list_roots(struct btrfs_root *root)
 788 {
 789         struct btrfs_key key;
 790         struct btrfs_key found_key;
 791         struct btrfs_disk_key disk_key;
 792         struct btrfs_path *path;
 793         struct extent_buffer *leaf;
 794         struct btrfs_root_item ri;
 795         unsigned long offset;
 796         int slot;
 797         int ret;
 798
 799         root = root->fs_info->tree_root;
 800         path = btrfs_alloc_path();
 801         if (!path) {
 802                 fprintf(stderr, "Failed to alloc path\n");
 803                 return -1;
 804         }
 805
 806         key.offset = 0;
 807         key.objectid = 0;
 808         key.type = BTRFS_ROOT_ITEM_KEY;
 809
 810         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
 811         if (ret < 0) {
 812                 fprintf(stderr, "Failed to do search %d\n", ret);
 813                 btrfs_free_path(path);
 814                 return -1;
 815         }
 816
 817         while (1) {
 818                 leaf = path->nodes[0];
 819                 slot = path->slots[0];
 820                 if (slot >= btrfs_header_nritems(leaf)) {
 821                         ret = btrfs_next_leaf(root, path);
 822                         if (ret)
 823                                 break;
 824                         leaf = path->nodes[0];
 825                         slot = path->slots[0];
 826                 }
 827                 btrfs_item_key(leaf, &disk_key, slot);
 828                 btrfs_disk_key_to_cpu(&found_key, &disk_key);
 829                 if (btrfs_key_type(&found_key) != BTRFS_ROOT_ITEM_KEY) {
 830                         path->slots[0]++;
 831                         continue;
 832                 }
 833
 834                 offset = btrfs_item_ptr_offset(leaf, slot);
 835                 read_extent_buffer(leaf, &ri, offset, sizeof(ri));
 836                 printf(" tree ");
 837                 btrfs_print_key(&disk_key);
 838                 printf(" %Lu level %d\n", btrfs_root_bytenr(&ri),
 839                        btrfs_root_level(&ri));
 840                 path->slots[0]++;
 841         }
 842         btrfs_free_path(path);
 843
 844         return 0;
 845 }
 846
 847 static struct btrfs_root *open_fs(const char *dev, u64 root_location,
 848                                   int super_mirror, int list_roots)
 849 {
 850         struct btrfs_fs_info *fs_info = NULL;
 851         struct btrfs_root *root = NULL;
 852         u64 bytenr;
 853         int i;
 854
 855         for (i = super_mirror; i < BTRFS_SUPER_MIRROR_MAX; i++) {
 856                 bytenr = btrfs_sb_offset(i);
 857                 fs_info = open_ctree_fs_info(dev, bytenr, root_location, 0, 1);
 858                 if (fs_info)
 859                         break;
 860                 fprintf(stderr, "Could not open root, trying backup super\n");
 861         }
 862
 863         if (!fs_info)
 864                 return NULL;
 865
 866         /*
 867          * All we really need to succeed is reading the chunk tree, everything
 868          * else we can do by hand, since we only need to read the tree root and
 869          * the fs_root.
 870          */
 871         if (!extent_buffer_uptodate(fs_info->tree_root->node)) {
 872                 u64 generation;
 873
 874                 root = fs_info->tree_root;
 875                 if (!root_location)
 876                         root_location = btrfs_super_root(fs_info->super_copy);
 877                 generation = btrfs_super_generation(fs_info->super_copy);
 878                 root->node = read_tree_block(root, root_location,
 879                                              root->leafsize, generation);
 880                 if (!extent_buffer_uptodate(root->node)) {
 881                         fprintf(stderr, "Error opening tree root\n");
 882                         close_ctree(root);
 883                         return NULL;
 884                 }
 885         }
 886
 887         if (!list_roots && !fs_info->fs_root) {
 888                 struct btrfs_key key;
 889
 890                 key.objectid = BTRFS_FS_TREE_OBJECTID;
 891                 key.type = BTRFS_ROOT_ITEM_KEY;
 892                 key.offset = (u64)-1;
 893                 fs_info->fs_root = btrfs_read_fs_root_no_cache(fs_info, &key);
 894                 if (IS_ERR(fs_info->fs_root)) {
 895                         fprintf(stderr, "Couldn't read fs root: %ld\n",
 896                                 PTR_ERR(fs_info->fs_root));
 897                         close_ctree(fs_info->tree_root);
 898                         return NULL;
 899                 }
 900         }
 901
 902         if (list_roots && do_list_roots(fs_info->tree_root)) {
 903                 close_ctree(fs_info->tree_root);
 904                 return NULL;
 905         }
 906
 907         return fs_info->fs_root;
 908 }
 909
 910 static int find_first_dir(struct btrfs_root *root, u64 *objectid)
 911 {
 912         struct btrfs_path *path;
 913         struct btrfs_key found_key;
 914         struct btrfs_key key;
 915         int ret = -1;
 916         int i;
 917
 918         key.objectid = 0;
 919         key.type = BTRFS_DIR_INDEX_KEY;
 920         key.offset = 0;
 921
 922         path = btrfs_alloc_path();
 923         if (!path) {
 924                 fprintf(stderr, "Ran out of memory\n");
 925                 return ret;
 926         }
 927
 928         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
 929         if (ret < 0) {
 930                 fprintf(stderr, "Error searching %d\n", ret);
 931                 goto out;
 932         }
 933
 934         if (!path->nodes[0]) {
 935                 fprintf(stderr, "No leaf!\n");
 936                 goto out;
 937         }
 938 again:
 939         for (i = path->slots[0];
 940              i < btrfs_header_nritems(path->nodes[0]); i++) {
 941                 btrfs_item_key_to_cpu(path->nodes[0], &found_key, i);
 942                 if (found_key.type != key.type)
 943                         continue;
 944
 945                 printf("Using objectid %Lu for first dir\n",
 946                        found_key.objectid);
 947                 *objectid = found_key.objectid;
 948                 ret = 0;
 949                 goto out;
 950         }
 951         do {
 952                 ret = next_leaf(root, path);
 953                 if (ret < 0) {
 954                         fprintf(stderr, "Error getting next leaf %d\n",
 955                                 ret);
 956                         goto out;
 957                 } else if (ret > 0) {
 958                         fprintf(stderr, "No more leaves\n");
 959                         goto out;
 960                 }
 961         } while (!path->nodes[0]);
 962         if (path->nodes[0])
 963                 goto again;
 964         printf("Couldn't find a dir index item\n");
 965 out:
 966         btrfs_free_path(path);
 967         return ret;
 968 }
 969
 970 const char * const cmd_restore_usage[] = {
 971         "btrfs restore [options] <device>",
 972         "Try to restore files from a damaged filesystem (unmounted)",
 973         "",
 974         "-s              get snapshots",
 975         "-v              verbose",
 976         "-i              ignore errors",
 977         "-o              overwrite",
 978         "-t              tree location",
 979         "-f <offset>     filesystem location",
 980         "-u <block>      super mirror",
 981         "-d              find dir",
 982         NULL
 983 };
 984
 985 int cmd_restore(int argc, char **argv)
 986 {
 987         struct btrfs_root *root;
 988         struct btrfs_key key;
 989         char dir_name[128];
 990         u64 tree_location = 0;
 991         u64 fs_location = 0;
 992         u64 root_objectid = 0;
 993         int len;
 994         int ret;
 995         int opt;
 996         int super_mirror = 0;
 997         int find_dir = 0;
 998         int list_roots = 0;
 999         const char *match_regstr = NULL;
1000         int match_cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
1001         regex_t match_reg, *mreg = NULL;
1002         char reg_err[256];
1003
1004         while ((opt = getopt(argc, argv, "sviot:u:df:r:lcm:")) != -1) {
1005
1006                 switch (opt) {
1007                         case 's':
1008                                 get_snaps = 1;
1009                                 break;
1010                         case 'v':
1011                                 verbose++;
1012                                 break;
1013                         case 'i':
1014                                 ignore_errors = 1;
1015                                 break;
1016                         case 'o':
1017                                 overwrite = 1;
1018                                 break;
1019                         case 't':
1020                                 errno = 0;
1021                                 tree_location = (u64)strtoll(optarg, NULL, 10);
1022                                 if (errno != 0) {
1023                                         fprintf(stderr, "Tree location not valid\n");
1024                                         exit(1);
1025                                 }
1026                                 break;
1027                         case 'f':
1028                                 errno = 0;
1029                                 fs_location = (u64)strtoll(optarg, NULL, 10);
1030                                 if (errno != 0) {
1031                                         fprintf(stderr, "Fs location not valid\n");
1032                                         exit(1);
1033                                 }
1034                                 break;
1035                         case 'u':
1036                                 errno = 0;
1037                                 super_mirror = (int)strtol(optarg, NULL, 10);
1038                                 if (errno != 0 ||
1039                                     super_mirror >= BTRFS_SUPER_MIRROR_MAX) {
1040                                         fprintf(stderr, "Super mirror not "
1041                                                 "valid\n");
1042                                         exit(1);
1043                                 }
1044                                 break;
1045                         case 'd':
1046                                 find_dir = 1;
1047                                 break;
1048                         case 'r':
1049                                 errno = 0;
1050                                 root_objectid = (u64)strtoll(optarg, NULL, 10);
1051                                 if (errno != 0) {
1052                                         fprintf(stderr, "Root objectid not valid\n");
1053                                         exit(1);
1054                                 }
1055                                 break;
1056                         case 'l':
1057                                 list_roots = 1;
1058                                 break;
1059                         case 'c':
1060                                 match_cflags |= REG_ICASE;
1061                                 break;
1062                         case 'm':
1063                                 match_regstr = optarg;
1064                                 break;
1065                         default:
1066                                 usage(cmd_restore_usage);
1067                 }
1068         }
1069
1070         if (!list_roots && optind + 1 >= argc)
1071                 usage(cmd_restore_usage);
1072         else if (list_roots && optind >= argc)
1073                 usage(cmd_restore_usage);
1074
1075         if ((ret = check_mounted(argv[optind])) < 0) {
1076                 fprintf(stderr, "Could not check mount status: %s\n",
1077                         strerror(-ret));
1078                 return ret;
1079         } else if (ret) {
1080                 fprintf(stderr, "%s is currently mounted.  Aborting.\n", argv[optind]);
1081                 return 1;
1082         }
1083
1084         root = open_fs(argv[optind], tree_location, super_mirror, list_roots);
1085         if (root == NULL)
1086                 return 1;
1087
1088         if (list_roots)
1089                 goto out;
1090
1091         if (fs_location != 0) {
1092                 free_extent_buffer(root->node);
1093                 root->node = read_tree_block(root, fs_location, root->leafsize, 0);
1094                 if (!root->node) {
1095                         fprintf(stderr, "Failed to read fs location\n");
1096                         goto out;
1097                 }
1098         }
1099
1100         memset(path_name, 0, 4096);
1101
1102         strncpy(dir_name, argv[optind + 1], sizeof dir_name);
1103         dir_name[sizeof dir_name - 1] = 0;
1104
1105         /* Strip the trailing / on the dir name */
1106         len = strlen(dir_name);
1107         while (len && dir_name[--len] == '/') {
1108                 dir_name[len] = '\0';
1109         }
1110
1111         if (root_objectid != 0) {
1112                 struct btrfs_root *orig_root = root;
1113
1114                 key.objectid = root_objectid;
1115                 key.type = BTRFS_ROOT_ITEM_KEY;
1116                 key.offset = (u64)-1;
1117                 root = btrfs_read_fs_root(orig_root->fs_info, &key);
1118                 if (IS_ERR(root)) {
1119                         fprintf(stderr, "Error reading root\n");
1120                         root = orig_root;
1121                         ret = 1;
1122                         goto out;
1123                 }
1124                 key.type = 0;
1125                 key.offset = 0;
1126         }
1127
1128         if (find_dir) {
1129                 ret = find_first_dir(root, &key.objectid);
1130                 if (ret)
1131                         goto out;
1132         } else {
1133                 key.objectid = BTRFS_FIRST_FREE_OBJECTID;
1134         }
1135
1136         if (match_regstr) {
1137                 ret = regcomp(&match_reg, match_regstr, match_cflags);
1138                 if (ret) {
1139                         regerror(ret, &match_reg, reg_err, sizeof(reg_err));
1140                         fprintf(stderr, "Regex compile failed: %s\n", reg_err);
1141                         goto out;
1142                 }
1143                 mreg = &match_reg;
1144         }
1145
1146         ret = search_dir(root, &key, dir_name, "", mreg);
1147
1148 out:
1149         if (mreg)
1150                 regfree(mreg);
1151         close_ctree(root);
1152         return ret;
1153 }