cmds-inspect.c

   1 /*
   2  * This program is free software; you can redistribute it and/or
   3  * modify it under the terms of the GNU General Public
   4  * License v2 as published by the Free Software Foundation.
   5  *
   6  * This program is distributed in the hope that it will be useful,
   7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
   8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   9  * General Public License for more details.
  10  *
  11  * You should have received a copy of the GNU General Public
  12  * License along with this program; if not, write to the
  13  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  14  * Boston, MA 021110-1307, USA.
  15  */
  16
  17 #include <stdio.h>
  18 #include <stdlib.h>
  19 #include <unistd.h>
  20 #include <stdint.h>
  21 #include <sys/ioctl.h>
  22 #include <errno.h>
  23 #include <getopt.h>
  24 #include <limits.h>
  25
  26 #include "kerncompat.h"
  27 #include "ioctl.h"
  28 #include "utils.h"
  29 #include "ctree.h"
  30 #include "send-utils.h"
  31 #include "disk-io.h"
  32 #include "commands.h"
  33 #include "btrfs-list.h"
  34 #include "cmds-inspect-dump-tree.h"
  35 #include "cmds-inspect-dump-super.h"
  36
  37 static const char * const inspect_cmd_group_usage[] = {
  38         "btrfs inspect-internal <command> <args>",
  39         NULL
  40 };
  41
  42 static int __ino_to_path_fd(u64 inum, int fd, int verbose, const char *prepend)
  43 {
  44         int ret;
  45         int i;
  46         struct btrfs_ioctl_ino_path_args ipa;
  47         struct btrfs_data_container fspath[PATH_MAX];
  48
  49         memset(fspath, 0, sizeof(*fspath));
  50         ipa.inum = inum;
  51         ipa.size = PATH_MAX;
  52         ipa.fspath = ptr_to_u64(fspath);
  53
  54         ret = ioctl(fd, BTRFS_IOC_INO_PATHS, &ipa);
  55         if (ret < 0) {
  56                 printf("ioctl ret=%d, error: %s\n", ret, strerror(errno));
  57                 goto out;
  58         }
  59
  60         if (verbose)
  61                 printf("ioctl ret=%d, bytes_left=%lu, bytes_missing=%lu, "
  62                         "cnt=%d, missed=%d\n", ret,
  63                         (unsigned long)fspath->bytes_left,
  64                         (unsigned long)fspath->bytes_missing,
  65                         fspath->elem_cnt, fspath->elem_missed);
  66
  67         for (i = 0; i < fspath->elem_cnt; ++i) {
  68                 u64 ptr;
  69                 char *str;
  70                 ptr = (u64)(unsigned long)fspath->val;
  71                 ptr += fspath->val[i];
  72                 str = (char *)(unsigned long)ptr;
  73                 if (prepend)
  74                         printf("%s/%s\n", prepend, str);
  75                 else
  76                         printf("%s\n", str);
  77         }
  78
  79 out:
  80         return !!ret;
  81 }
  82
  83 static const char * const cmd_inspect_inode_resolve_usage[] = {
  84         "btrfs inspect-internal inode-resolve [-v] <inode> <path>",
  85         "Get file system paths for the given inode",
  86         "",
  87         "-v   verbose mode",
  88         NULL
  89 };
  90
  91 static int cmd_inspect_inode_resolve(int argc, char **argv)
  92 {
  93         int fd;
  94         int verbose = 0;
  95         int ret;
  96         DIR *dirstream = NULL;
  97
  98         optind = 1;
  99         while (1) {
 100                 int c = getopt(argc, argv, "v");
 101                 if (c < 0)
 102                         break;
 103
 104                 switch (c) {
 105                 case 'v':
 106                         verbose = 1;
 107                         break;
 108                 default:
 109                         usage(cmd_inspect_inode_resolve_usage);
 110                 }
 111         }
 112
 113         if (check_argc_exact(argc - optind, 2))
 114                 usage(cmd_inspect_inode_resolve_usage);
 115
 116         fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
 117         if (fd < 0)
 118                 return 1;
 119
 120         ret = __ino_to_path_fd(arg_strtou64(argv[optind]), fd, verbose,
 121                                argv[optind+1]);
 122         close_file_or_dir(fd, dirstream);
 123         return !!ret;
 124
 125 }
 126
 127 static const char * const cmd_inspect_logical_resolve_usage[] = {
 128         "btrfs inspect-internal logical-resolve [-Pv] [-s bufsize] <logical> <path>",
 129         "Get file system paths for the given logical address",
 130         "-P          skip the path resolving and print the inodes instead",
 131         "-v          verbose mode",
 132         "-s bufsize  set inode container's size. This is used to increase inode",
 133         "            container's size in case it is not enough to read all the ",
 134         "            resolved results. The max value one can set is 64k",
 135         NULL
 136 };
 137
 138 static int cmd_inspect_logical_resolve(int argc, char **argv)
 139 {
 140         int ret;
 141         int fd;
 142         int i;
 143         int verbose = 0;
 144         int getpath = 1;
 145         int bytes_left;
 146         struct btrfs_ioctl_logical_ino_args loi;
 147         struct btrfs_data_container *inodes;
 148         u64 size = 4096;
 149         char full_path[4096];
 150         char *path_ptr;
 151         DIR *dirstream = NULL;
 152
 153         optind = 1;
 154         while (1) {
 155                 int c = getopt(argc, argv, "Pvs:");
 156                 if (c < 0)
 157                         break;
 158
 159                 switch (c) {
 160                 case 'P':
 161                         getpath = 0;
 162                         break;
 163                 case 'v':
 164                         verbose = 1;
 165                         break;
 166                 case 's':
 167                         size = arg_strtou64(optarg);
 168                         break;
 169                 default:
 170                         usage(cmd_inspect_logical_resolve_usage);
 171                 }
 172         }
 173
 174         if (check_argc_exact(argc - optind, 2))
 175                 usage(cmd_inspect_logical_resolve_usage);
 176
 177         size = min(size, (u64)64 * 1024);
 178         inodes = malloc(size);
 179         if (!inodes)
 180                 return 1;
 181
 182         memset(inodes, 0, sizeof(*inodes));
 183         loi.logical = arg_strtou64(argv[optind]);
 184         loi.size = size;
 185         loi.inodes = ptr_to_u64(inodes);
 186
 187         fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
 188         if (fd < 0) {
 189                 ret = 12;
 190                 goto out;
 191         }
 192
 193         ret = ioctl(fd, BTRFS_IOC_LOGICAL_INO, &loi);
 194         if (ret < 0) {
 195                 printf("ioctl ret=%d, error: %s\n", ret, strerror(errno));
 196                 goto out;
 197         }
 198
 199         if (verbose)
 200                 printf("ioctl ret=%d, total_size=%llu, bytes_left=%lu, "
 201                         "bytes_missing=%lu, cnt=%d, missed=%d\n",
 202                         ret, size,
 203                         (unsigned long)inodes->bytes_left,
 204                         (unsigned long)inodes->bytes_missing,
 205                         inodes->elem_cnt, inodes->elem_missed);
 206
 207         bytes_left = sizeof(full_path);
 208         ret = snprintf(full_path, bytes_left, "%s/", argv[optind+1]);
 209         path_ptr = full_path + ret;
 210         bytes_left -= ret + 1;
 211         BUG_ON(bytes_left < 0);
 212
 213         for (i = 0; i < inodes->elem_cnt; i += 3) {
 214                 u64 inum = inodes->val[i];
 215                 u64 offset = inodes->val[i+1];
 216                 u64 root = inodes->val[i+2];
 217                 int path_fd;
 218                 char *name;
 219                 DIR *dirs = NULL;
 220
 221                 if (getpath) {
 222                         name = btrfs_list_path_for_root(fd, root);
 223                         if (IS_ERR(name)) {
 224                                 ret = PTR_ERR(name);
 225                                 goto out;
 226                         }
 227                         if (!name) {
 228                                 path_ptr[-1] = '\0';
 229                                 path_fd = fd;
 230                         } else {
 231                                 path_ptr[-1] = '/';
 232                                 ret = snprintf(path_ptr, bytes_left, "%s",
 233                                                 name);
 234                                 BUG_ON(ret >= bytes_left);
 235                                 free(name);
 236                                 path_fd = btrfs_open_dir(full_path, &dirs, 1);
 237                                 if (path_fd < 0) {
 238                                         ret = -ENOENT;
 239                                         goto out;
 240                                 }
 241                         }
 242                         __ino_to_path_fd(inum, path_fd, verbose, full_path);
 243                         if (path_fd != fd)
 244                                 close_file_or_dir(path_fd, dirs);
 245                 } else {
 246                         printf("inode %llu offset %llu root %llu\n", inum,
 247                                 offset, root);
 248                 }
 249         }
 250
 251 out:
 252         close_file_or_dir(fd, dirstream);
 253         free(inodes);
 254         return !!ret;
 255 }
 256
 257 static const char * const cmd_inspect_subvolid_resolve_usage[] = {
 258         "btrfs inspect-internal subvolid-resolve <subvolid> <path>",
 259         "Get file system paths for the given subvolume ID.",
 260         NULL
 261 };
 262
 263 static int cmd_inspect_subvolid_resolve(int argc, char **argv)
 264 {
 265         int ret;
 266         int fd = -1;
 267         u64 subvol_id;
 268         char path[PATH_MAX];
 269         DIR *dirstream = NULL;
 270
 271         if (check_argc_exact(argc, 3))
 272                 usage(cmd_inspect_subvolid_resolve_usage);
 273
 274         fd = btrfs_open_dir(argv[2], &dirstream, 1);
 275         if (fd < 0) {
 276                 ret = -ENOENT;
 277                 goto out;
 278         }
 279
 280         subvol_id = arg_strtou64(argv[1]);
 281         ret = btrfs_subvolid_resolve(fd, path, sizeof(path), subvol_id);
 282
 283         if (ret) {
 284                 fprintf(stderr,
 285                         "%s: btrfs_subvolid_resolve(subvol_id %llu) failed with ret=%d\n",
 286                         argv[0], (unsigned long long)subvol_id, ret);
 287                 goto out;
 288         }
 289
 290         path[PATH_MAX - 1] = '\0';
 291         printf("%s\n", path);
 292
 293 out:
 294         close_file_or_dir(fd, dirstream);
 295         return ret ? 1 : 0;
 296 }
 297
 298 static const char* const cmd_inspect_rootid_usage[] = {
 299         "btrfs inspect-internal rootid <path>",
 300         "Get tree ID of the containing subvolume of path.",
 301         NULL
 302 };
 303
 304 static int cmd_inspect_rootid(int argc, char **argv)
 305 {
 306         int ret;
 307         int fd = -1;
 308         u64 rootid;
 309         DIR *dirstream = NULL;
 310
 311         if (check_argc_exact(argc, 2))
 312                 usage(cmd_inspect_rootid_usage);
 313
 314         fd = btrfs_open_dir(argv[1], &dirstream, 1);
 315         if (fd < 0) {
 316                 ret = -ENOENT;
 317                 goto out;
 318         }
 319
 320         ret = lookup_ino_rootid(fd, &rootid);
 321         if (ret) {
 322                 fprintf(stderr, "%s: rootid failed with ret=%d\n",
 323                         argv[0], ret);
 324                 goto out;
 325         }
 326
 327         printf("%llu\n", (unsigned long long)rootid);
 328 out:
 329         close_file_or_dir(fd, dirstream);
 330
 331         return !!ret;
 332 }
 333
 334 static const char* const cmd_inspect_min_dev_size_usage[] = {
 335         "btrfs inspect-internal min-dev-size [options] <path>",
 336         "Get the minimum size the device can be shrunk to. The",
 337         "device id 1 is used by default.",
 338         "--id DEVID   specify the device id to query",
 339         NULL
 340 };
 341
 342 struct dev_extent_elem {
 343         u64 start;
 344         /* inclusive end */
 345         u64 end;
 346         struct list_head list;
 347 };
 348
 349 static int add_dev_extent(struct list_head *list,
 350                           const u64 start, const u64 end,
 351                           const int append)
 352 {
 353         struct dev_extent_elem *e;
 354
 355         e = malloc(sizeof(*e));
 356         if (!e)
 357                 return -ENOMEM;
 358
 359         e->start = start;
 360         e->end = end;
 361
 362         if (append)
 363                 list_add_tail(&e->list, list);
 364         else
 365                 list_add(&e->list, list);
 366
 367         return 0;
 368 }
 369
 370 static void free_dev_extent_list(struct list_head *list)
 371 {
 372         while (!list_empty(list)) {
 373                 struct dev_extent_elem *e;
 374
 375                 e = list_first_entry(list, struct dev_extent_elem, list);
 376                 list_del(&e->list);
 377                 free(e);
 378         }
 379 }
 380
 381 static int hole_includes_sb_mirror(const u64 start, const u64 end)
 382 {
 383         int i;
 384         int ret = 0;
 385
 386         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
 387                 u64 bytenr = btrfs_sb_offset(i);
 388
 389                 if (bytenr >= start && bytenr <= end) {
 390                         ret = 1;
 391                         break;
 392                 }
 393         }
 394
 395         return ret;
 396 }
 397
 398 static void adjust_dev_min_size(struct list_head *extents,
 399                                 struct list_head *holes,
 400                                 u64 *min_size)
 401 {
 402         /*
 403          * If relocation of the block group of a device extent must happen (see
 404          * below) scratch space is used for the relocation. So track here the
 405          * size of the largest device extent that has to be relocated. We track
 406          * only the largest and not the sum of the sizes of all relocated block
 407          * groups because after each block group is relocated the running
 408          * transaction is committed so that pinned space is released.
 409          */
 410         u64 scratch_space = 0;
 411
 412         /*
 413          * List of device extents is sorted by descending order of the extent's
 414          * end offset. If some extent goes beyond the computed minimum size,
 415          * which initially matches the sum of the lenghts of all extents,
 416          * we need to check if the extent can be relocated to an hole in the
 417          * device between [0, *min_size[ (which is what the resize ioctl does).
 418          */
 419         while (!list_empty(extents)) {
 420                 struct dev_extent_elem *e;
 421                 struct dev_extent_elem *h;
 422                 int found = 0;
 423                 u64 extent_len;
 424                 u64 hole_len = 0;
 425
 426                 e = list_first_entry(extents, struct dev_extent_elem, list);
 427                 if (e->end <= *min_size)
 428                         break;
 429
 430                 /*
 431                  * Our extent goes beyond the computed *min_size. See if we can
 432                  * find a hole large enough to relocate it to. If not we must stop
 433                  * and set *min_size to the end of the extent.
 434                  */
 435                 extent_len = e->end - e->start + 1;
 436                 list_for_each_entry(h, holes, list) {
 437                         hole_len = h->end - h->start + 1;
 438                         if (hole_len >= extent_len) {
 439                                 found = 1;
 440                                 break;
 441                         }
 442                 }
 443
 444                 if (!found) {
 445                         *min_size = e->end + 1;
 446                         break;
 447                 }
 448
 449                 /*
 450                  * If the hole found contains the location for a superblock
 451                  * mirror, we are pessimistic and require allocating one
 452                  * more extent of the same size. This is because the block
 453                  * group could be in the worst case used by a single extent
 454                  * with a size >= (block_group.length - superblock.size).
 455                  */
 456                 if (hole_includes_sb_mirror(h->start,
 457                                             h->start + extent_len - 1))
 458                         *min_size += extent_len;
 459
 460                 if (hole_len > extent_len) {
 461                         h->start += extent_len;
 462                 } else {
 463                         list_del(&h->list);
 464                         free(h);
 465                 }
 466
 467                 list_del(&e->list);
 468                 free(e);
 469
 470                 if (extent_len > scratch_space)
 471                         scratch_space = extent_len;
 472         }
 473
 474         if (scratch_space) {
 475                 *min_size += scratch_space;
 476                 /*
 477                  * Chunk allocation requires inserting/updating items in the
 478                  * chunk tree, so often this can lead to the need of allocating
 479                  * a new system chunk too, which has a maximum size of 32Mb.
 480                  */
 481                 *min_size += 32 * 1024 * 1024;
 482         }
 483 }
 484
 485 static int print_min_dev_size(int fd, u64 devid)
 486 {
 487         int ret = 1;
 488         /*
 489          * Device allocations starts at 1Mb or at the value passed through the
 490          * mount option alloc_start if it's bigger than 1Mb. The alloc_start
 491          * option is used for debugging and testing only, and recently the
 492          * possibility of deprecating/removing it has been discussed, so we
 493          * ignore it here.
 494          */
 495         u64 min_size = 1 * 1024 * 1024ull;
 496         struct btrfs_ioctl_search_args args;
 497         struct btrfs_ioctl_search_key *sk = &args.key;
 498         u64 last_pos = (u64)-1;
 499         LIST_HEAD(extents);
 500         LIST_HEAD(holes);
 501
 502         memset(&args, 0, sizeof(args));
 503         sk->tree_id = BTRFS_DEV_TREE_OBJECTID;
 504         sk->min_objectid = devid;
 505         sk->max_objectid = devid;
 506         sk->max_type = BTRFS_DEV_EXTENT_KEY;
 507         sk->min_type = BTRFS_DEV_EXTENT_KEY;
 508         sk->min_offset = 0;
 509         sk->max_offset = (u64)-1;
 510         sk->min_transid = 0;
 511         sk->max_transid = (u64)-1;
 512         sk->nr_items = 4096;
 513
 514         while (1) {
 515                 int i;
 516                 struct btrfs_ioctl_search_header *sh;
 517                 unsigned long off = 0;
 518
 519                 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
 520                 if (ret < 0) {
 521                         fprintf(stderr,
 522                                 "Error invoking tree search ioctl: %s\n",
 523                                 strerror(errno));
 524                         ret = 1;
 525                         goto out;
 526                 }
 527
 528                 if (sk->nr_items == 0)
 529                         break;
 530
 531                 for (i = 0; i < sk->nr_items; i++) {
 532                         struct btrfs_dev_extent *extent;
 533                         u64 len;
 534
 535                         sh = (struct btrfs_ioctl_search_header *)(args.buf +
 536                                                                   off);
 537                         off += sizeof(*sh);
 538                         extent = (struct btrfs_dev_extent *)(args.buf + off);
 539                         off += sh->len;
 540
 541                         sk->min_objectid = sh->objectid;
 542                         sk->min_type = sh->type;
 543                         sk->min_offset = sh->offset + 1;
 544
 545                         if (sh->objectid != devid ||
 546                             sh->type != BTRFS_DEV_EXTENT_KEY)
 547                                 continue;
 548
 549                         len = btrfs_stack_dev_extent_length(extent);
 550                         min_size += len;
 551                         ret = add_dev_extent(&extents, sh->offset,
 552                                              sh->offset + len - 1, 0);
 553
 554                         if (!ret && last_pos != (u64)-1 &&
 555                             last_pos != sh->offset)
 556                                 ret = add_dev_extent(&holes, last_pos,
 557                                                      sh->offset - 1, 1);
 558                         if (ret) {
 559                                 fprintf(stderr, "Error: %s\n", strerror(-ret));
 560                                 ret = 1;
 561                                 goto out;
 562                         }
 563
 564                         last_pos = sh->offset + len;
 565                 }
 566
 567                 if (sk->min_type != BTRFS_DEV_EXTENT_KEY ||
 568                     sk->min_objectid != devid)
 569                         break;
 570         }
 571
 572         adjust_dev_min_size(&extents, &holes, &min_size);
 573         printf("%llu bytes (%s)\n", min_size, pretty_size(min_size));
 574         ret = 0;
 575 out:
 576         free_dev_extent_list(&extents);
 577         free_dev_extent_list(&holes);
 578
 579         return ret;
 580 }
 581
 582 static int cmd_inspect_min_dev_size(int argc, char **argv)
 583 {
 584         int ret;
 585         int fd = -1;
 586         DIR *dirstream = NULL;
 587         u64 devid = 1;
 588
 589         while (1) {
 590                 int c;
 591                 enum { GETOPT_VAL_DEVID = 256 };
 592                 static const struct option long_options[] = {
 593                         { "id", required_argument, NULL, GETOPT_VAL_DEVID },
 594                         {NULL, 0, NULL, 0}
 595                 };
 596
 597                 c = getopt_long(argc, argv, "", long_options, NULL);
 598                 if (c < 0)
 599                         break;
 600
 601                 switch (c) {
 602                 case GETOPT_VAL_DEVID:
 603                         devid = arg_strtou64(optarg);
 604                         break;
 605                 default:
 606                         usage(cmd_inspect_min_dev_size_usage);
 607                 }
 608         }
 609         if (check_argc_exact(argc - optind, 1))
 610                 usage(cmd_inspect_min_dev_size_usage);
 611
 612         fd = btrfs_open_dir(argv[optind], &dirstream, 1);
 613         if (fd < 0) {
 614                 ret = -ENOENT;
 615                 goto out;
 616         }
 617
 618         ret = print_min_dev_size(fd, devid);
 619         close_file_or_dir(fd, dirstream);
 620 out:
 621         return !!ret;
 622 }
 623
 624 static int cmd_inspect_dump_tree_hook(int ac, char **av)
 625 {
 626         return cmd_inspect_dump_tree(ac, av);
 627 }
 628
 629 static int cmd_inspect_dump_super_hook(int ac, char **av)
 630 {
 631         return cmd_inspect_dump_super(ac, av);
 632 }
 633
 634 static const char inspect_cmd_group_info[] =
 635 "query various internal information";
 636
 637 const struct cmd_group inspect_cmd_group = {
 638         inspect_cmd_group_usage, inspect_cmd_group_info, {
 639                 { "inode-resolve", cmd_inspect_inode_resolve,
 640                         cmd_inspect_inode_resolve_usage, NULL, 0 },
 641                 { "logical-resolve", cmd_inspect_logical_resolve,
 642                         cmd_inspect_logical_resolve_usage, NULL, 0 },
 643                 { "subvolid-resolve", cmd_inspect_subvolid_resolve,
 644                         cmd_inspect_subvolid_resolve_usage, NULL, 0 },
 645                 { "rootid", cmd_inspect_rootid, cmd_inspect_rootid_usage, NULL,
 646                         0 },
 647                 { "min-dev-size", cmd_inspect_min_dev_size,
 648                         cmd_inspect_min_dev_size_usage, NULL, 0 },
 649                 { "dump-tree", cmd_inspect_dump_tree_hook,
 650                                 cmd_inspect_dump_tree_usage, NULL, 0 },
 651                 { "dump-super", cmd_inspect_dump_super_hook,
 652                                 cmd_inspect_dump_super_usage, NULL, 0 },
 653                 NULL_CMD_STRUCT
 654         }
 655 };
 656
 657 int cmd_inspect(int argc, char **argv)
 658 {
 659         return handle_command_group(&inspect_cmd_group, argc, argv);
 660 }