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