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