cmds-restore.c

   1 /*
   2  * Copyright (C) 2011 Red Hat.  All rights reserved.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public
   6  * License v2 as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public
  14  * License along with this program; if not, write to the
  15  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  16  * Boston, MA 021110-1307, USA.
  17  */
  18
  19 #define _XOPEN_SOURCE 500
  20 #define _GNU_SOURCE 1
  21
  22 #include "kerncompat.h"
  23
  24 #include <ctype.h>
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <unistd.h>
  28 #include <fcntl.h>
  29 #include <sys/stat.h>
  30 #include <sys/types.h>
  31 #include <lzo/lzoconf.h>
  32 #include <lzo/lzo1x.h>
  33 #include <zlib.h>
  34 #include <regex.h>
  35 #include <getopt.h>
  36 #include <sys/types.h>
  37 #include <sys/xattr.h>
  38
  39 #include "ctree.h"
  40 #include "disk-io.h"
  41 #include "print-tree.h"
  42 #include "transaction.h"
  43 #include "list.h"
  44 #include "version.h"
  45 #include "volumes.h"
  46 #include "utils.h"
  47 #include "commands.h"
  48
  49 static char fs_name[4096];
  50 static char path_name[4096];
  51 static int get_snaps = 0;
  52 static int verbose = 0;
  53 static int ignore_errors = 0;
  54 static int overwrite = 0;
  55 static int get_xattrs = 0;
  56 static int dry_run = 0;
  57
  58 #define LZO_LEN 4
  59 #define PAGE_CACHE_SIZE 4096
  60 #define lzo1x_worst_compress(x) ((x) + ((x) / 16) + 64 + 3)
  61
  62 static int decompress_zlib(char *inbuf, char *outbuf, u64 compress_len,
  63                            u64 decompress_len)
  64 {
  65         z_stream strm;
  66         int ret;
  67
  68         memset(&strm, 0, sizeof(strm));
  69         ret = inflateInit(&strm);
  70         if (ret != Z_OK) {
  71                 fprintf(stderr, "inflate init returnd %d\n", ret);
  72                 return -1;
  73         }
  74
  75         strm.avail_in = compress_len;
  76         strm.next_in = (unsigned char *)inbuf;
  77         strm.avail_out = decompress_len;
  78         strm.next_out = (unsigned char *)outbuf;
  79         ret = inflate(&strm, Z_NO_FLUSH);
  80         if (ret != Z_STREAM_END) {
  81                 (void)inflateEnd(&strm);
  82                 fprintf(stderr, "failed to inflate: %d\n", ret);
  83                 return -1;
  84         }
  85
  86         (void)inflateEnd(&strm);
  87         return 0;
  88 }
  89 static inline size_t read_compress_length(unsigned char *buf)
  90 {
  91         __le32 dlen;
  92         memcpy(&dlen, buf, LZO_LEN);
  93         return le32_to_cpu(dlen);
  94 }
  95
  96 static int decompress_lzo(unsigned char *inbuf, char *outbuf, u64 compress_len,
  97                           u64 *decompress_len)
  98 {
  99         size_t new_len;
 100         size_t in_len;
 101         size_t out_len = 0;
 102         size_t tot_len;
 103         size_t tot_in;
 104         int ret;
 105
 106         ret = lzo_init();
 107         if (ret != LZO_E_OK) {
 108                 fprintf(stderr, "lzo init returned %d\n", ret);
 109                 return -1;
 110         }
 111
 112         tot_len = read_compress_length(inbuf);
 113         inbuf += LZO_LEN;
 114         tot_in = LZO_LEN;
 115
 116         while (tot_in < tot_len) {
 117                 in_len = read_compress_length(inbuf);
 118
 119                 if ((tot_in + LZO_LEN + in_len) > tot_len) {
 120                         fprintf(stderr, "bad compress length %lu\n",
 121                                 (unsigned long)in_len);
 122                         return -1;
 123                 }
 124
 125                 inbuf += LZO_LEN;
 126                 tot_in += LZO_LEN;
 127
 128                 new_len = lzo1x_worst_compress(PAGE_CACHE_SIZE);
 129                 ret = lzo1x_decompress_safe((const unsigned char *)inbuf, in_len,
 130                                             (unsigned char *)outbuf,
 131                                             (void *)&new_len, NULL);
 132                 if (ret != LZO_E_OK) {
 133                         fprintf(stderr, "failed to inflate: %d\n", ret);
 134                         return -1;
 135                 }
 136                 out_len += new_len;
 137                 outbuf += new_len;
 138                 inbuf += in_len;
 139                 tot_in += in_len;
 140         }
 141
 142         *decompress_len = out_len;
 143
 144         return 0;
 145 }
 146
 147 static int decompress(char *inbuf, char *outbuf, u64 compress_len,
 148                       u64 *decompress_len, int compress)
 149 {
 150         switch (compress) {
 151         case BTRFS_COMPRESS_ZLIB:
 152                 return decompress_zlib(inbuf, outbuf, compress_len,
 153                                        *decompress_len);
 154         case BTRFS_COMPRESS_LZO:
 155                 return decompress_lzo((unsigned char *)inbuf, outbuf, compress_len,
 156                                       decompress_len);
 157         default:
 158                 break;
 159         }
 160
 161         fprintf(stderr, "invalid compression type: %d\n", compress);
 162         return -1;
 163 }
 164
 165 static int next_leaf(struct btrfs_root *root, struct btrfs_path *path)
 166 {
 167         int slot;
 168         int level = 1;
 169         int offset = 1;
 170         struct extent_buffer *c;
 171         struct extent_buffer *next = NULL;
 172
 173 again:
 174         for (; level < BTRFS_MAX_LEVEL; level++) {
 175                 if (path->nodes[level])
 176                         break;
 177         }
 178
 179         if (level == BTRFS_MAX_LEVEL)
 180                 return 1;
 181
 182         slot = path->slots[level] + 1;
 183
 184         while(level < BTRFS_MAX_LEVEL) {
 185                 if (!path->nodes[level])
 186                         return 1;
 187
 188                 slot = path->slots[level] + offset;
 189                 c = path->nodes[level];
 190                 if (slot >= btrfs_header_nritems(c)) {
 191                         level++;
 192                         if (level == BTRFS_MAX_LEVEL)
 193                                 return 1;
 194                         offset = 1;
 195                         continue;
 196                 }
 197
 198                 if (path->reada)
 199                         reada_for_search(root, path, level, slot, 0);
 200
 201                 next = read_node_slot(root, c, slot);
 202                 if (next)
 203                         break;
 204                 offset++;
 205         }
 206         path->slots[level] = slot;
 207         while(1) {
 208                 level--;
 209                 c = path->nodes[level];
 210                 free_extent_buffer(c);
 211                 path->nodes[level] = next;
 212                 path->slots[level] = 0;
 213                 if (!level)
 214                         break;
 215                 if (path->reada)
 216                         reada_for_search(root, path, level, 0, 0);
 217                 next = read_node_slot(root, next, 0);
 218                 if (!next)
 219                         goto again;
 220         }
 221         return 0;
 222 }
 223
 224 static int copy_one_inline(int fd, struct btrfs_path *path, u64 pos)
 225 {
 226         struct extent_buffer *leaf = path->nodes[0];
 227         struct btrfs_file_extent_item *fi;
 228         char buf[4096];
 229         char *outbuf;
 230         u64 ram_size;
 231         ssize_t done;
 232         unsigned long ptr;
 233         int ret;
 234         int len;
 235         int inline_item_len;
 236         int compress;
 237
 238         fi = btrfs_item_ptr(leaf, path->slots[0],
 239                             struct btrfs_file_extent_item);
 240         ptr = btrfs_file_extent_inline_start(fi);
 241         len = btrfs_file_extent_inline_len(leaf, path->slots[0], fi);
 242         inline_item_len = btrfs_file_extent_inline_item_len(leaf, btrfs_item_nr(path->slots[0]));
 243         read_extent_buffer(leaf, buf, ptr, inline_item_len);
 244
 245         compress = btrfs_file_extent_compression(leaf, fi);
 246         if (compress == BTRFS_COMPRESS_NONE) {
 247                 done = pwrite(fd, buf, len, pos);
 248                 if (done < len) {
 249                         fprintf(stderr, "Short inline write, wanted %d, did "
 250                                 "%zd: %d\n", len, done, errno);
 251                         return -1;
 252                 }
 253                 return 0;
 254         }
 255
 256         ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
 257         outbuf = calloc(1, ram_size);
 258         if (!outbuf) {
 259                 fprintf(stderr, "No memory\n");
 260                 return -ENOMEM;
 261         }
 262
 263         ret = decompress(buf, outbuf, len, &ram_size, compress);
 264         if (ret) {
 265                 free(outbuf);
 266                 return ret;
 267         }
 268
 269         done = pwrite(fd, outbuf, ram_size, pos);
 270         free(outbuf);
 271         if (done < ram_size) {
 272                 fprintf(stderr, "Short compressed inline write, wanted %Lu, "
 273                         "did %zd: %d\n", ram_size, done, errno);
 274                 return -1;
 275         }
 276
 277         return 0;
 278 }
 279
 280 static int copy_one_extent(struct btrfs_root *root, int fd,
 281                            struct extent_buffer *leaf,
 282                            struct btrfs_file_extent_item *fi, u64 pos)
 283 {
 284         struct btrfs_multi_bio *multi = NULL;
 285         struct btrfs_device *device;
 286         char *inbuf, *outbuf = NULL;
 287         ssize_t done, total = 0;
 288         u64 bytenr;
 289         u64 ram_size;
 290         u64 disk_size;
 291         u64 num_bytes;
 292         u64 length;
 293         u64 size_left;
 294         u64 dev_bytenr;
 295         u64 offset;
 296         u64 count = 0;
 297         int compress;
 298         int ret;
 299         int dev_fd;
 300         int mirror_num = 1;
 301         int num_copies;
 302
 303         compress = btrfs_file_extent_compression(leaf, fi);
 304         bytenr = btrfs_file_extent_disk_bytenr(leaf, fi);
 305         disk_size = btrfs_file_extent_disk_num_bytes(leaf, fi);
 306         ram_size = btrfs_file_extent_ram_bytes(leaf, fi);
 307         offset = btrfs_file_extent_offset(leaf, fi);
 308         num_bytes = btrfs_file_extent_num_bytes(leaf, fi);
 309         size_left = disk_size;
 310         if (compress == BTRFS_COMPRESS_NONE)
 311                 bytenr += offset;
 312
 313         if (verbose && offset)
 314                 printf("offset is %Lu\n", offset);
 315         /* we found a hole */
 316         if (disk_size == 0)
 317                 return 0;
 318
 319         inbuf = malloc(size_left);
 320         if (!inbuf) {
 321                 fprintf(stderr, "No memory\n");
 322                 return -ENOMEM;
 323         }
 324
 325         if (compress != BTRFS_COMPRESS_NONE) {
 326                 outbuf = calloc(1, ram_size);
 327                 if (!outbuf) {
 328                         fprintf(stderr, "No memory\n");
 329                         free(inbuf);
 330                         return -ENOMEM;
 331                 }
 332         }
 333 again:
 334         length = size_left;
 335         ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
 336                               bytenr, &length, &multi, mirror_num, NULL);
 337         if (ret) {
 338                 fprintf(stderr, "Error mapping block %d\n", ret);
 339                 goto out;
 340         }
 341         device = multi->stripes[0].dev;
 342         dev_fd = device->fd;
 343         device->total_ios++;
 344         dev_bytenr = multi->stripes[0].physical;
 345         kfree(multi);
 346
 347         if (size_left < length)
 348                 length = size_left;
 349
 350         done = pread(dev_fd, inbuf+count, length, dev_bytenr);
 351         /* Need both checks, or we miss negative values due to u64 conversion */
 352         if (done < 0 || done < length) {
 353                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 354                                               bytenr, length);
 355                 mirror_num++;
 356                 /* mirror_num is 1-indexed, so num_copies is a valid mirror. */
 357                 if (mirror_num > num_copies) {
 358                         ret = -1;
 359                         fprintf(stderr, "Exhausted mirrors trying to read\n");
 360                         goto out;
 361                 }
 362                 fprintf(stderr, "Trying another mirror\n");
 363                 goto again;
 364         }
 365
 366         mirror_num = 1;
 367         size_left -= length;
 368         count += length;
 369         bytenr += length;
 370         if (size_left)
 371                 goto again;
 372
 373         if (compress == BTRFS_COMPRESS_NONE) {
 374                 while (total < num_bytes) {
 375                         done = pwrite(fd, inbuf+total, num_bytes-total,
 376                                       pos+total);
 377                         if (done < 0) {
 378                                 ret = -1;
 379                                 fprintf(stderr, "Error writing: %d %s\n", errno, strerror(errno));
 380                                 goto out;
 381                         }
 382                         total += done;
 383                 }
 384                 ret = 0;
 385                 goto out;
 386         }
 387
 388         ret = decompress(inbuf, outbuf, disk_size, &ram_size, compress);
 389         if (ret) {
 390                 num_copies = btrfs_num_copies(&root->fs_info->mapping_tree,
 391                                               bytenr, length);
 392                 mirror_num++;
 393                 if (mirror_num >= num_copies) {
 394                         ret = -1;
 395                         goto out;
 396                 }
 397                 fprintf(stderr, "Trying another mirror\n");
 398                 goto again;
 399         }
 400
 401         while (total < num_bytes) {
 402                 done = pwrite(fd, outbuf + offset + total,
 403                               num_bytes - total,
 404                               pos + total);
 405                 if (done < 0) {
 406                         ret = -1;
 407                         goto out;
 408                 }
 409                 total += done;
 410         }
 411 out:
 412         free(inbuf);
 413         free(outbuf);
 414         return ret;
 415 }
 416
 417 enum loop_response {
 418         LOOP_STOP,
 419         LOOP_CONTINUE,
 420         LOOP_DONTASK
 421 };
 422
 423 static enum loop_response ask_to_continue(const char *file)
 424 {
 425         char buf[2];
 426         char *ret;
 427
 428         printf("We seem to be looping a lot on %s, do you want to keep going "
 429                "on ? (y/N/a): ", file);
 430 again:
 431         ret = fgets(buf, 2, stdin);
 432         if (*ret == '\n' || tolower(*ret) == 'n')
 433                 return LOOP_STOP;
 434         if (tolower(*ret) == 'a')
 435                 return LOOP_DONTASK;
 436         if (tolower(*ret) != 'y') {
 437                 printf("Please enter one of 'y', 'n', or 'a': ");
 438                 goto again;
 439         }
 440
 441         return LOOP_CONTINUE;
 442 }
 443
 444
 445 static int set_file_xattrs(struct btrfs_root *root, u64 inode,
 446                            int fd, const char *file_name)
 447 {
 448         struct btrfs_key key;
 449         struct btrfs_path *path;
 450         struct extent_buffer *leaf;
 451         struct btrfs_dir_item *di;
 452         u32 name_len = 0;
 453         u32 data_len = 0;
 454         u32 len = 0;
 455         u32 cur, total_len;
 456         char *name = NULL;
 457         char *data = NULL;
 458         int ret = 0;
 459
 460         key.objectid = inode;
 461         key.type = BTRFS_XATTR_ITEM_KEY;
 462         key.offset = 0;
 463
 464         path = btrfs_alloc_path();
 465         if (!path)
 466                 return -ENOMEM;
 467
 468         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
 469         if (ret < 0)
 470                 goto out;
 471
 472         leaf = path->nodes[0];
 473         while (1) {
 474                 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
 475                         do {
 476                                 ret = next_leaf(root, path);
 477                                 if (ret < 0) {
 478                                         fprintf(stderr,
 479                                                 "Error searching for extended attributes: %d\n",
 480                                                 ret);
 481                                         goto out;
 482                                 } else if (ret) {
 483                                         /* No more leaves to search */
 484                                         ret = 0;
 485                                         goto out;
 486                                 }
 487                                 leaf = path->nodes[0];
 488                         } while (!leaf);
 489                         continue;
 490                 }
 491
 492                 btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
 493                 if (key.type != BTRFS_XATTR_ITEM_KEY || key.objectid != inode)
 494                         break;
 495                 cur = 0;
 496                 total_len = btrfs_item_size_nr(leaf, path->slots[0]);
 497                 di = btrfs_item_ptr(leaf, path->slots[0],
 498                                     struct btrfs_dir_item);
 499
 500                 while (cur < total_len) {
 501                         len = btrfs_dir_name_len(leaf, di);
 502                         if (len > name_len) {
 503                                 free(name);
 504                                 name = (char *) malloc(len + 1);
 505                                 if (!name) {
 506                                         ret = -ENOMEM;
 507                                         goto out;
 508                                 }
 509                         }
 510                         read_extent_buffer(leaf, name,
 511                                            (unsigned long)(di + 1), len);
 512                         name[len] = '\0';
 513                         name_len = len;
 514
 515                         len = btrfs_dir_data_len(leaf, di);
 516                         if (len > data_len) {
 517                                 free(data);
 518                                 data = (char *) malloc(len);
 519                                 if (!data) {
 520                                         ret = -ENOMEM;
 521                                         goto out;
 522                                 }
 523                         }
 524                         read_extent_buffer(leaf, data,
 525                                            (unsigned long)(di + 1) + name_len,
 526                                            len);
 527                         data_len = len;
 528
 529                         if (fsetxattr(fd, name, data, data_len, 0)) {
 530                                 int err = errno;
 531
 532                                 fprintf(stderr,
 533                                         "Error setting extended attribute %s on file %s: %s\n",
 534                                         name, file_name, strerror(err));
 535                         }
 536
 537                         len = sizeof(*di) + name_len + data_len;
 538                         cur += len;
 539                         di = (struct btrfs_dir_item *)((char *)di + len);
 540                 }
 541                 path->slots[0]++;
 542         }
 543         ret = 0;
 544 out:
 545         btrfs_free_path(path);
 546         free(name);
 547         free(data);
 548
 549         return ret;
 550 }
 551
 552
 553 static int copy_file(struct btrfs_root *root, int fd, struct btrfs_key *key,
 554                      const char *file)
 555 {
 556         struct extent_buffer *leaf;
 557         struct btrfs_path *path;
 558         struct btrfs_file_extent_item *fi;
 559         struct btrfs_inode_item *inode_item;
 560         struct btrfs_key found_key;
 561         int ret;
 562         int extent_type;
 563         int compression;
 564         int loops = 0;
 565         u64 found_size = 0;
 566
 567         path = btrfs_alloc_path();
 568         if (!path) {
 569                 fprintf(stderr, "Ran out of memory\n");
 570                 return -ENOMEM;
 571         }
 572
 573         ret = btrfs_lookup_inode(NULL, root, path, key, 0);
 574         if (ret == 0) {
 575                 inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
 576                                     struct btrfs_inode_item);
 577                 found_size = btrfs_inode_size(path->nodes[0], inode_item);
 578         }
 579         btrfs_release_path(path);
 580
 581         key->offset = 0;
 582         key->type = BTRFS_EXTENT_DATA_KEY;
 583
 584         ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
 585         if (ret < 0) {
 586                 fprintf(stderr, "Error searching %d\n", ret);
 587                 btrfs_free_path(path);
 588                 return ret;
 589         }
 590
 591         leaf = path->nodes[0];
 592         while (!leaf) {
 593                 ret = next_leaf(root, path);
 594                 if (ret < 0) {
 595                         fprintf(stderr, "Error getting next leaf %d\n",
 596                                 ret);
 597                         btrfs_free_path(path);
 598                         return ret;
 599                 } else if (ret > 0) {
 600                         /* No more leaves to search */
 601                         btrfs_free_path(path);
 602                         return 0;
 603                 }
 604                 leaf = path->nodes[0];
 605         }
 606
 607         while (1) {
 608                 if (loops >= 0 && loops++ >= 1024) {
 609                         enum loop_response resp;
 610
 611                         resp = ask_to_continue(file);
 612                         if (resp == LOOP_STOP)
 613                                 break;
 614                         else if (resp == LOOP_CONTINUE)
 615                                 loops = 0;
 616                         else if (resp == LOOP_DONTASK)
 617                                 loops = -1;
 618                 }
 619                 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
 620                         do {
 621                                 ret = next_leaf(root, path);
 622                                 if (ret < 0) {
 623                                         fprintf(stderr, "Error searching %d\n", ret);
 624                                         btrfs_free_path(path);
 625                                         return ret;
 626                                 } else if (ret) {
 627                                         /* No more leaves to search */
 628                                         btrfs_free_path(path);
 629                                         goto set_size;
 630                                 }
 631                                 leaf = path->nodes[0];
 632                         } while (!leaf);
 633                         continue;
 634                 }
 635                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 636                 if (found_key.objectid != key->objectid)
 637                         break;
 638                 if (found_key.type != key->type)
 639                         break;
 640                 fi = btrfs_item_ptr(leaf, path->slots[0],
 641                                     struct btrfs_file_extent_item);
 642                 extent_type = btrfs_file_extent_type(leaf, fi);
 643                 compression = btrfs_file_extent_compression(leaf, fi);
 644                 if (compression >= BTRFS_COMPRESS_LAST) {
 645                         fprintf(stderr, "Don't support compression yet %d\n",
 646                                 compression);
 647                         btrfs_free_path(path);
 648                         return -1;
 649                 }
 650
 651                 if (extent_type == BTRFS_FILE_EXTENT_PREALLOC)
 652                         goto next;
 653                 if (extent_type == BTRFS_FILE_EXTENT_INLINE) {
 654                         ret = copy_one_inline(fd, path, found_key.offset);
 655                         if (ret) {
 656                                 btrfs_free_path(path);
 657                                 return -1;
 658                         }
 659                 } else if (extent_type == BTRFS_FILE_EXTENT_REG) {
 660                         ret = copy_one_extent(root, fd, leaf, fi,
 661                                               found_key.offset);
 662                         if (ret) {
 663                                 btrfs_free_path(path);
 664                                 return ret;
 665                         }
 666                 } else {
 667                         printf("Weird extent type %d\n", extent_type);
 668                 }
 669 next:
 670                 path->slots[0]++;
 671         }
 672
 673         btrfs_free_path(path);
 674 set_size:
 675         if (found_size) {
 676                 ret = ftruncate(fd, (loff_t)found_size);
 677                 if (ret)
 678                         return ret;
 679         }
 680         if (get_xattrs) {
 681                 ret = set_file_xattrs(root, key->objectid, fd, file);
 682                 if (ret)
 683                         return ret;
 684         }
 685         return 0;
 686 }
 687
 688 static int search_dir(struct btrfs_root *root, struct btrfs_key *key,
 689                       const char *output_rootdir, const char *in_dir,
 690                       const regex_t *mreg)
 691 {
 692         struct btrfs_path *path;
 693         struct extent_buffer *leaf;
 694         struct btrfs_dir_item *dir_item;
 695         struct btrfs_key found_key, location;
 696         char filename[BTRFS_NAME_LEN + 1];
 697         unsigned long name_ptr;
 698         int name_len;
 699         int ret;
 700         int fd;
 701         int loops = 0;
 702         u8 type;
 703
 704         path = btrfs_alloc_path();
 705         if (!path) {
 706                 fprintf(stderr, "Ran out of memory\n");
 707                 return -ENOMEM;
 708         }
 709
 710         key->offset = 0;
 711         key->type = BTRFS_DIR_INDEX_KEY;
 712
 713         ret = btrfs_search_slot(NULL, root, key, path, 0, 0);
 714         if (ret < 0) {
 715                 fprintf(stderr, "Error searching %d\n", ret);
 716                 btrfs_free_path(path);
 717                 return ret;
 718         }
 719
 720         leaf = path->nodes[0];
 721         while (!leaf) {
 722                 if (verbose > 1)
 723                         printf("No leaf after search, looking for the next "
 724                                "leaf\n");
 725                 ret = next_leaf(root, path);
 726                 if (ret < 0) {
 727                         fprintf(stderr, "Error getting next leaf %d\n",
 728                                 ret);
 729                         btrfs_free_path(path);
 730                         return ret;
 731                 } else if (ret > 0) {
 732                         /* No more leaves to search */
 733                         if (verbose)
 734                                 printf("Reached the end of the tree looking "
 735                                        "for the directory\n");
 736                         btrfs_free_path(path);
 737                         return 0;
 738                 }
 739                 leaf = path->nodes[0];
 740         }
 741
 742         while (leaf) {
 743                 if (loops++ >= 1024) {
 744                         printf("We have looped trying to restore files in %s "
 745                                "too many times to be making progress, "
 746                                "stopping\n", in_dir);
 747                         break;
 748                 }
 749
 750                 if (path->slots[0] >= btrfs_header_nritems(leaf)) {
 751                         do {
 752                                 ret = next_leaf(root, path);
 753                                 if (ret < 0) {
 754                                         fprintf(stderr, "Error searching %d\n",
 755                                                 ret);
 756                                         btrfs_free_path(path);
 757                                         return ret;
 758                                 } else if (ret > 0) {
 759                                         /* No more leaves to search */
 760                                         if (verbose)
 761                                                 printf("Reached the end of "
 762                                                        "the tree searching the"
 763                                                        " directory\n");
 764                                         btrfs_free_path(path);
 765                                         return 0;
 766                                 }
 767                                 leaf = path->nodes[0];
 768                         } while (!leaf);
 769                         continue;
 770                 }
 771                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
 772                 if (found_key.objectid != key->objectid) {
 773                         if (verbose > 1)
 774                                 printf("Found objectid=%Lu, key=%Lu\n",
 775                                        found_key.objectid, key->objectid);
 776                         break;
 777                 }
 778                 if (found_key.type != key->type) {
 779                         if (verbose > 1)
 780                                 printf("Found type=%u, want=%u\n",
 781                                        found_key.type, key->type);
 782                         break;
 783                 }
 784                 dir_item = btrfs_item_ptr(leaf, path->slots[0],
 785                                           struct btrfs_dir_item);
 786                 name_ptr = (unsigned long)(dir_item + 1);
 787                 name_len = btrfs_dir_name_len(leaf, dir_item);
 788                 read_extent_buffer(leaf, filename, name_ptr, name_len);
 789                 filename[name_len] = '\0';
 790                 type = btrfs_dir_type(leaf, dir_item);
 791                 btrfs_dir_item_key_to_cpu(leaf, dir_item, &location);
 792
 793                 /* full path from root of btrfs being restored */
 794                 snprintf(fs_name, 4096, "%s/%s", in_dir, filename);
 795
 796                 if (mreg && REG_NOMATCH == regexec(mreg, fs_name, 0, NULL, 0))
 797                         goto next;
 798
 799                 /* full path from system root */
 800                 snprintf(path_name, 4096, "%s%s", output_rootdir, fs_name);
 801
 802                 /*
 803                  * At this point we're only going to restore directories and
 804                  * files, no symlinks or anything else.
 805                  */
 806                 if (type == BTRFS_FT_REG_FILE) {
 807                         if (!overwrite) {
 808                                 static int warn = 0;
 809                                 struct stat st;
 810
 811                                 ret = stat(path_name, &st);
 812                                 if (!ret) {
 813                                         loops = 0;
 814                                         if (verbose || !warn)
 815                                                 printf("Skipping existing file"
 816                                                        " %s\n", path_name);
 817                                         if (warn)
 818                                                 goto next;
 819                                         printf("If you wish to overwrite use "
 820                                                "the -o option to overwrite\n");
 821                                         warn = 1;
 822                                         goto next;
 823                                 }
 824                                 ret = 0;
 825                         }
 826                         if (verbose)
 827                                 printf("Restoring %s\n", path_name);
 828                         if (dry_run)
 829                                 goto next;
 830                         fd = open(path_name, O_CREAT|O_WRONLY, 0644);
 831                         if (fd < 0) {
 832                                 fprintf(stderr, "Error creating %s: %d\n",
 833                                         path_name, errno);
 834                                 if (ignore_errors)
 835                                         goto next;
 836                                 btrfs_free_path(path);
 837                                 return -1;
 838                         }
 839                         loops = 0;
 840                         ret = copy_file(root, fd, &location, path_name);
 841                         close(fd);
 842                         if (ret) {
 843                                 if (ignore_errors)
 844                                         goto next;
 845                                 btrfs_free_path(path);
 846                                 return ret;
 847                         }
 848                 } else if (type == BTRFS_FT_DIR) {
 849                         struct btrfs_root *search_root = root;
 850                         char *dir = strdup(fs_name);
 851
 852                         if (!dir) {
 853                                 fprintf(stderr, "Ran out of memory\n");
 854                                 btrfs_free_path(path);
 855                                 return -ENOMEM;
 856                         }
 857
 858                         if (location.type == BTRFS_ROOT_ITEM_KEY) {
 859                                 /*
 860                                  * If we are a snapshot and this is the index
 861                                  * object to ourselves just skip it.
 862                                  */
 863                                 if (location.objectid ==
 864                                     root->root_key.objectid) {
 865                                         free(dir);
 866                                         goto next;
 867                                 }
 868
 869                                 location.offset = (u64)-1;
 870                                 search_root = btrfs_read_fs_root(root->fs_info,
 871                                                                  &location);
 872                                 if (IS_ERR(search_root)) {
 873                                         free(dir);
 874                                         fprintf(stderr, "Error reading "
 875                                                 "subvolume %s: %lu\n",
 876                                                 path_name,
 877                                                 PTR_ERR(search_root));
 878                                         if (ignore_errors)
 879                                                 goto next;
 880                                         btrfs_free_path(path);
 881                                         return PTR_ERR(search_root);
 882                                 }
 883
 884                                 /*
 885                                  * A subvolume will have a key.offset of 0, a
 886                                  * snapshot will have key.offset of a transid.
 887                                  */
 888                                 if (search_root->root_key.offset != 0 &&
 889                                     get_snaps == 0) {
 890                                         free(dir);
 891                                         printf("Skipping snapshot %s\n",
 892                                                filename);
 893                                         goto next;
 894                                 }
 895                                 location.objectid = BTRFS_FIRST_FREE_OBJECTID;
 896                         }
 897
 898                         if (verbose)
 899                                 printf("Restoring %s\n", path_name);
 900
 901                         errno = 0;
 902                         if (dry_run)
 903                                 ret = 0;
 904                         else
 905                                 ret = mkdir(path_name, 0755);
 906                         if (ret && errno != EEXIST) {
 907                                 free(dir);
 908                                 fprintf(stderr, "Error mkdiring %s: %d\n",
 909                                         path_name, errno);
 910                                 if (ignore_errors)
 911                                         goto next;
 912                                 btrfs_free_path(path);
 913                                 return -1;
 914                         }
 915                         loops = 0;
 916                         ret = search_dir(search_root, &location,
 917                                          output_rootdir, dir, mreg);
 918                         free(dir);
 919                         if (ret) {
 920                                 if (ignore_errors)
 921                                         goto next;
 922                                 btrfs_free_path(path);
 923                                 return ret;
 924                         }
 925                 }
 926 next:
 927                 path->slots[0]++;
 928         }
 929
 930         if (verbose)
 931                 printf("Done searching %s\n", in_dir);
 932         btrfs_free_path(path);
 933         return 0;
 934 }
 935
 936 static int do_list_roots(struct btrfs_root *root)
 937 {
 938         struct btrfs_key key;
 939         struct btrfs_key found_key;
 940         struct btrfs_disk_key disk_key;
 941         struct btrfs_path *path;
 942         struct extent_buffer *leaf;
 943         struct btrfs_root_item ri;
 944         unsigned long offset;
 945         int slot;
 946         int ret;
 947
 948         root = root->fs_info->tree_root;
 949         path = btrfs_alloc_path();
 950         if (!path) {
 951                 fprintf(stderr, "Failed to alloc path\n");
 952                 return -ENOMEM;
 953         }
 954
 955         key.offset = 0;
 956         key.objectid = 0;
 957         key.type = BTRFS_ROOT_ITEM_KEY;
 958
 959         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
 960         if (ret < 0) {
 961                 fprintf(stderr, "Failed to do search %d\n", ret);
 962                 btrfs_free_path(path);
 963                 return -1;
 964         }
 965
 966         while (1) {
 967                 leaf = path->nodes[0];
 968                 slot = path->slots[0];
 969                 if (slot >= btrfs_header_nritems(leaf)) {
 970                         ret = btrfs_next_leaf(root, path);
 971                         if (ret)
 972                                 break;
 973                         leaf = path->nodes[0];
 974                         slot = path->slots[0];
 975                 }
 976                 btrfs_item_key(leaf, &disk_key, slot);
 977                 btrfs_disk_key_to_cpu(&found_key, &disk_key);
 978                 if (btrfs_key_type(&found_key) != BTRFS_ROOT_ITEM_KEY) {
 979                         path->slots[0]++;
 980                         continue;
 981                 }
 982
 983                 offset = btrfs_item_ptr_offset(leaf, slot);
 984                 read_extent_buffer(leaf, &ri, offset, sizeof(ri));
 985                 printf(" tree ");
 986                 btrfs_print_key(&disk_key);
 987                 printf(" %Lu level %d\n", btrfs_root_bytenr(&ri),
 988                        btrfs_root_level(&ri));
 989                 path->slots[0]++;
 990         }
 991         btrfs_free_path(path);
 992
 993         return 0;
 994 }
 995
 996 static struct btrfs_root *open_fs(const char *dev, u64 root_location,
 997                                   int super_mirror, int list_roots)
 998 {
 999         struct btrfs_fs_info *fs_info = NULL;
1000         struct btrfs_root *root = NULL;
1001         u64 bytenr;
1002         int i;
1003
1004         for (i = super_mirror; i < BTRFS_SUPER_MIRROR_MAX; i++) {
1005                 bytenr = btrfs_sb_offset(i);
1006                 fs_info = open_ctree_fs_info(dev, bytenr, root_location,
1007                                              OPEN_CTREE_PARTIAL);
1008                 if (fs_info)
1009                         break;
1010                 fprintf(stderr, "Could not open root, trying backup super\n");
1011         }
1012
1013         if (!fs_info)
1014                 return NULL;
1015
1016         /*
1017          * All we really need to succeed is reading the chunk tree, everything
1018          * else we can do by hand, since we only need to read the tree root and
1019          * the fs_root.
1020          */
1021         if (!extent_buffer_uptodate(fs_info->tree_root->node)) {
1022                 u64 generation;
1023
1024                 root = fs_info->tree_root;
1025                 if (!root_location)
1026                         root_location = btrfs_super_root(fs_info->super_copy);
1027                 generation = btrfs_super_generation(fs_info->super_copy);
1028                 root->node = read_tree_block(root, root_location,
1029                                              root->leafsize, generation);
1030                 if (!extent_buffer_uptodate(root->node)) {
1031                         fprintf(stderr, "Error opening tree root\n");
1032                         close_ctree(root);
1033                         return NULL;
1034                 }
1035         }
1036
1037         if (!list_roots && !fs_info->fs_root) {
1038                 struct btrfs_key key;
1039
1040                 key.objectid = BTRFS_FS_TREE_OBJECTID;
1041                 key.type = BTRFS_ROOT_ITEM_KEY;
1042                 key.offset = (u64)-1;
1043                 fs_info->fs_root = btrfs_read_fs_root_no_cache(fs_info, &key);
1044                 if (IS_ERR(fs_info->fs_root)) {
1045                         fprintf(stderr, "Couldn't read fs root: %ld\n",
1046                                 PTR_ERR(fs_info->fs_root));
1047                         close_ctree(fs_info->tree_root);
1048                         return NULL;
1049                 }
1050         }
1051
1052         if (list_roots && do_list_roots(fs_info->tree_root)) {
1053                 close_ctree(fs_info->tree_root);
1054                 return NULL;
1055         }
1056
1057         return fs_info->fs_root;
1058 }
1059
1060 static int find_first_dir(struct btrfs_root *root, u64 *objectid)
1061 {
1062         struct btrfs_path *path;
1063         struct btrfs_key found_key;
1064         struct btrfs_key key;
1065         int ret = -1;
1066         int i;
1067
1068         key.objectid = 0;
1069         key.type = BTRFS_DIR_INDEX_KEY;
1070         key.offset = 0;
1071
1072         path = btrfs_alloc_path();
1073         if (!path) {
1074                 fprintf(stderr, "Ran out of memory\n");
1075                 return ret;
1076         }
1077
1078         ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
1079         if (ret < 0) {
1080                 fprintf(stderr, "Error searching %d\n", ret);
1081                 goto out;
1082         }
1083
1084         if (!path->nodes[0]) {
1085                 fprintf(stderr, "No leaf!\n");
1086                 goto out;
1087         }
1088 again:
1089         for (i = path->slots[0];
1090              i < btrfs_header_nritems(path->nodes[0]); i++) {
1091                 btrfs_item_key_to_cpu(path->nodes[0], &found_key, i);
1092                 if (found_key.type != key.type)
1093                         continue;
1094
1095                 printf("Using objectid %Lu for first dir\n",
1096                        found_key.objectid);
1097                 *objectid = found_key.objectid;
1098                 ret = 0;
1099                 goto out;
1100         }
1101         do {
1102                 ret = next_leaf(root, path);
1103                 if (ret < 0) {
1104                         fprintf(stderr, "Error getting next leaf %d\n",
1105                                 ret);
1106                         goto out;
1107                 } else if (ret > 0) {
1108                         fprintf(stderr, "No more leaves\n");
1109                         goto out;
1110                 }
1111         } while (!path->nodes[0]);
1112         if (path->nodes[0])
1113                 goto again;
1114         printf("Couldn't find a dir index item\n");
1115 out:
1116         btrfs_free_path(path);
1117         return ret;
1118 }
1119
1120 static struct option long_options[] = {
1121         { "path-regex", 1, NULL, 256},
1122         { "dry-run", 0, NULL, 'D'},
1123         { NULL, 0, NULL, 0}
1124 };
1125
1126 const char * const cmd_restore_usage[] = {
1127         "btrfs restore [options] <device> <path> | -l <device>",
1128         "Try to restore files from a damaged filesystem (unmounted)",
1129         "",
1130         "-s              get snapshots",
1131         "-x              get extended attributes",
1132         "-v              verbose",
1133         "-i              ignore errors",
1134         "-o              overwrite",
1135         "-t <bytenr>     tree location",
1136         "-f <bytenr>     filesystem location",
1137         "-u <mirror>     super mirror",
1138         "-r <rootid>     root objectid",
1139         "-d              find dir",
1140         "-l              list tree roots",
1141         "-D|--dry-run    dry run (only list files that would be recovered)",
1142         "--path-regex <regex>",
1143         "                restore only filenames matching regex,",
1144         "                you have to use following syntax (possibly quoted):",
1145         "                ^/(|home(|/username(|/Desktop(|/.*))))$",
1146         "-c              ignore case (--path-regrex only)",
1147         NULL
1148 };
1149
1150 int cmd_restore(int argc, char **argv)
1151 {
1152         struct btrfs_root *root;
1153         struct btrfs_key key;
1154         char dir_name[128];
1155         u64 tree_location = 0;
1156         u64 fs_location = 0;
1157         u64 root_objectid = 0;
1158         int len;
1159         int ret;
1160         int opt;
1161         int option_index = 0;
1162         int super_mirror = 0;
1163         int find_dir = 0;
1164         int list_roots = 0;
1165         const char *match_regstr = NULL;
1166         int match_cflags = REG_EXTENDED | REG_NOSUB | REG_NEWLINE;
1167         regex_t match_reg, *mreg = NULL;
1168         char reg_err[256];
1169
1170         while ((opt = getopt_long(argc, argv, "sxviot:u:df:r:lDc", long_options,
1171                                         &option_index)) != -1) {
1172
1173                 switch (opt) {
1174                         case 's':
1175                                 get_snaps = 1;
1176                                 break;
1177                         case 'v':
1178                                 verbose++;
1179                                 break;
1180                         case 'i':
1181                                 ignore_errors = 1;
1182                                 break;
1183                         case 'o':
1184                                 overwrite = 1;
1185                                 break;
1186                         case 't':
1187                                 tree_location = arg_strtou64(optarg);
1188                                 break;
1189                         case 'f':
1190                                 fs_location = arg_strtou64(optarg);
1191                                 break;
1192                         case 'u':
1193                                 super_mirror = arg_strtou64(optarg);
1194                                 if (super_mirror >= BTRFS_SUPER_MIRROR_MAX) {
1195                                         fprintf(stderr, "Super mirror not "
1196                                                 "valid\n");
1197                                         exit(1);
1198                                 }
1199                                 break;
1200                         case 'd':
1201                                 find_dir = 1;
1202                                 break;
1203                         case 'r':
1204                                 root_objectid = arg_strtou64(optarg);
1205                                 if (!is_fstree(root_objectid)) {
1206                                         fprintf(stderr, "objectid %llu is not a valid fs/file tree\n",
1207                                                         root_objectid);
1208                                         exit(1);
1209                                 }
1210                                 break;
1211                         case 'l':
1212                                 list_roots = 1;
1213                                 break;
1214                         case 'D':
1215                                 dry_run = 1;
1216                                 break;
1217                         case 'c':
1218                                 match_cflags |= REG_ICASE;
1219                                 break;
1220                         /* long option without single letter alternative */
1221                         case 256:
1222                                 match_regstr = optarg;
1223                                 break;
1224                         case 'x':
1225                                 get_xattrs = 1;
1226                                 break;
1227                         default:
1228                                 usage(cmd_restore_usage);
1229                 }
1230         }
1231
1232         if (!list_roots && check_argc_min(argc - optind, 2))
1233                 usage(cmd_restore_usage);
1234         else if (list_roots && check_argc_min(argc - optind, 1))
1235                 usage(cmd_restore_usage);
1236
1237         if (fs_location && root_objectid) {
1238                 fprintf(stderr, "don't use -f and -r at the same time.\n");
1239                 return 1;
1240         }
1241
1242         if ((ret = check_mounted(argv[optind])) < 0) {
1243                 fprintf(stderr, "Could not check mount status: %s\n",
1244                         strerror(-ret));
1245                 return 1;
1246         } else if (ret) {
1247                 fprintf(stderr, "%s is currently mounted.  Aborting.\n", argv[optind]);
1248                 return 1;
1249         }
1250
1251         root = open_fs(argv[optind], tree_location, super_mirror, list_roots);
1252         if (root == NULL)
1253                 return 1;
1254
1255         if (list_roots)
1256                 goto out;
1257
1258         if (fs_location != 0) {
1259                 free_extent_buffer(root->node);
1260                 root->node = read_tree_block(root, fs_location, root->leafsize, 0);
1261                 if (!root->node) {
1262                         fprintf(stderr, "Failed to read fs location\n");
1263                         ret = 1;
1264                         goto out;
1265                 }
1266         }
1267
1268         memset(path_name, 0, 4096);
1269
1270         strncpy(dir_name, argv[optind + 1], sizeof dir_name);
1271         dir_name[sizeof dir_name - 1] = 0;
1272
1273         /* Strip the trailing / on the dir name */
1274         len = strlen(dir_name);
1275         while (len && dir_name[--len] == '/') {
1276                 dir_name[len] = '\0';
1277         }
1278
1279         if (root_objectid != 0) {
1280                 struct btrfs_root *orig_root = root;
1281
1282                 key.objectid = root_objectid;
1283                 key.type = BTRFS_ROOT_ITEM_KEY;
1284                 key.offset = (u64)-1;
1285                 root = btrfs_read_fs_root(orig_root->fs_info, &key);
1286                 if (IS_ERR(root)) {
1287                         fprintf(stderr, "fail to read root %llu: %s\n",
1288                                         root_objectid, strerror(-PTR_ERR(root)));
1289                         root = orig_root;
1290                         ret = 1;
1291                         goto out;
1292                 }
1293                 key.type = 0;
1294                 key.offset = 0;
1295         }
1296
1297         if (find_dir) {
1298                 ret = find_first_dir(root, &key.objectid);
1299                 if (ret)
1300                         goto out;
1301         } else {
1302                 key.objectid = BTRFS_FIRST_FREE_OBJECTID;
1303         }
1304
1305         if (match_regstr) {
1306                 ret = regcomp(&match_reg, match_regstr, match_cflags);
1307                 if (ret) {
1308                         regerror(ret, &match_reg, reg_err, sizeof(reg_err));
1309                         fprintf(stderr, "Regex compile failed: %s\n", reg_err);
1310                         goto out;
1311                 }
1312                 mreg = &match_reg;
1313         }
1314
1315         if (dry_run)
1316                 printf("This is a dry-run, no files are going to be restored\n");
1317
1318         ret = search_dir(root, &key, dir_name, "", mreg);
1319
1320 out:
1321         if (mreg)
1322                 regfree(mreg);
1323         close_ctree(root);
1324         return !!ret;
1325 }