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