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 "help.h"
  35
  36 static const char * const inspect_cmd_group_usage[] = {
  37         "btrfs inspect-internal <command> <args>",
  38         NULL
  39 };
  40
  41 static int __ino_to_path_fd(u64 inum, int fd, int verbose, const char *prepend)
  42 {
  43         int ret;
  44         int i;
  45         struct btrfs_ioctl_ino_path_args ipa;
  46         struct btrfs_data_container fspath[PATH_MAX];
  47
  48         memset(fspath, 0, sizeof(*fspath));
  49         ipa.inum = inum;
  50         ipa.size = PATH_MAX;
  51         ipa.fspath = ptr_to_u64(fspath);
  52
  53         ret = ioctl(fd, BTRFS_IOC_INO_PATHS, &ipa);
  54         if (ret < 0) {
  55                 error("ino paths ioctl: %m");
  56                 goto out;
  57         }
  58
  59         if (verbose)
  60                 printf("ioctl ret=%d, bytes_left=%lu, bytes_missing=%lu, "
  61                         "cnt=%d, missed=%d\n", ret,
  62                         (unsigned long)fspath->bytes_left,
  63                         (unsigned long)fspath->bytes_missing,
  64                         fspath->elem_cnt, fspath->elem_missed);
  65
  66         for (i = 0; i < fspath->elem_cnt; ++i) {
  67                 u64 ptr;
  68                 char *str;
  69                 ptr = (u64)(unsigned long)fspath->val;
  70                 ptr += fspath->val[i];
  71                 str = (char *)(unsigned long)ptr;
  72                 if (prepend)
  73                         printf("%s/%s\n", prepend, str);
  74                 else
  75                         printf("%s\n", str);
  76         }
  77
  78 out:
  79         return !!ret;
  80 }
  81
  82 static const char * const cmd_inspect_inode_resolve_usage[] = {
  83         "btrfs inspect-internal inode-resolve [-v] <inode> <path>",
  84         "Get file system paths for the given inode",
  85         "",
  86         "-v   verbose mode",
  87         NULL
  88 };
  89
  90 static int cmd_inspect_inode_resolve(int argc, char **argv)
  91 {
  92         int fd;
  93         int verbose = 0;
  94         int ret;
  95         DIR *dirstream = NULL;
  96
  97         optind = 0;
  98         while (1) {
  99                 int c = getopt(argc, argv, "v");
 100                 if (c < 0)
 101                         break;
 102
 103                 switch (c) {
 104                 case 'v':
 105                         verbose = 1;
 106                         break;
 107                 default:
 108                         usage(cmd_inspect_inode_resolve_usage);
 109                 }
 110         }
 111
 112         if (check_argc_exact(argc - optind, 2))
 113                 usage(cmd_inspect_inode_resolve_usage);
 114
 115         fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
 116         if (fd < 0)
 117                 return 1;
 118
 119         ret = __ino_to_path_fd(arg_strtou64(argv[optind]), fd, verbose,
 120                                argv[optind+1]);
 121         close_file_or_dir(fd, dirstream);
 122         return !!ret;
 123
 124 }
 125
 126 static const char * const cmd_inspect_logical_resolve_usage[] = {
 127         "btrfs inspect-internal logical-resolve [-Pv] [-s bufsize] <logical> <path>",
 128         "Get file system paths for the given logical address",
 129         "-P          skip the path resolving and print the inodes instead",
 130         "-v          verbose mode",
 131         "-s bufsize  set inode container's size. This is used to increase inode",
 132         "            container's size in case it is not enough to read all the ",
 133         "            resolved results. The max value one can set is 64k",
 134         NULL
 135 };
 136
 137 static int cmd_inspect_logical_resolve(int argc, char **argv)
 138 {
 139         int ret;
 140         int fd;
 141         int i;
 142         int verbose = 0;
 143         int getpath = 1;
 144         int bytes_left;
 145         struct btrfs_ioctl_logical_ino_args loi;
 146         struct btrfs_data_container *inodes;
 147         u64 size = 4096;
 148         char full_path[PATH_MAX];
 149         char *path_ptr;
 150         DIR *dirstream = NULL;
 151
 152         optind = 0;
 153         while (1) {
 154                 int c = getopt(argc, argv, "Pvs:");
 155                 if (c < 0)
 156                         break;
 157
 158                 switch (c) {
 159                 case 'P':
 160                         getpath = 0;
 161                         break;
 162                 case 'v':
 163                         verbose = 1;
 164                         break;
 165                 case 's':
 166                         size = arg_strtou64(optarg);
 167                         break;
 168                 default:
 169                         usage(cmd_inspect_logical_resolve_usage);
 170                 }
 171         }
 172
 173         if (check_argc_exact(argc - optind, 2))
 174                 usage(cmd_inspect_logical_resolve_usage);
 175
 176         size = min(size, (u64)SZ_64K);
 177         inodes = malloc(size);
 178         if (!inodes)
 179                 return 1;
 180
 181         memset(inodes, 0, sizeof(*inodes));
 182         loi.logical = arg_strtou64(argv[optind]);
 183         loi.size = size;
 184         loi.inodes = ptr_to_u64(inodes);
 185
 186         fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
 187         if (fd < 0) {
 188                 ret = 12;
 189                 goto out;
 190         }
 191
 192         ret = ioctl(fd, BTRFS_IOC_LOGICAL_INO, &loi);
 193         if (ret < 0) {
 194                 error("logical ino ioctl: %m");
 195                 goto out;
 196         }
 197
 198         if (verbose)
 199                 printf("ioctl ret=%d, total_size=%llu, bytes_left=%lu, "
 200                         "bytes_missing=%lu, cnt=%d, missed=%d\n",
 201                         ret, size,
 202                         (unsigned long)inodes->bytes_left,
 203                         (unsigned long)inodes->bytes_missing,
 204                         inodes->elem_cnt, inodes->elem_missed);
 205
 206         bytes_left = sizeof(full_path);
 207         ret = snprintf(full_path, bytes_left, "%s/", argv[optind+1]);
 208         path_ptr = full_path + ret;
 209         bytes_left -= ret + 1;
 210         if (bytes_left < 0) {
 211                 error("path buffer too small: %d bytes", bytes_left);
 212                 goto out;
 213         }
 214
 215         for (i = 0; i < inodes->elem_cnt; i += 3) {
 216                 u64 inum = inodes->val[i];
 217                 u64 offset = inodes->val[i+1];
 218                 u64 root = inodes->val[i+2];
 219                 int path_fd;
 220                 char *name;
 221                 DIR *dirs = NULL;
 222
 223                 if (getpath) {
 224                         name = btrfs_list_path_for_root(fd, root);
 225                         if (IS_ERR(name)) {
 226                                 ret = PTR_ERR(name);
 227                                 goto out;
 228                         }
 229                         if (!name) {
 230                                 path_ptr[-1] = '\0';
 231                                 path_fd = fd;
 232                         } else {
 233                                 path_ptr[-1] = '/';
 234                                 ret = snprintf(path_ptr, bytes_left, "%s",
 235                                                 name);
 236                                 free(name);
 237                                 if (ret >= bytes_left) {
 238                                         error("path buffer too small: %d bytes",
 239                                                         bytes_left - ret);
 240                                         goto out;
 241                                 }
 242                                 path_fd = btrfs_open_dir(full_path, &dirs, 1);
 243                                 if (path_fd < 0) {
 244                                         ret = -ENOENT;
 245                                         goto out;
 246                                 }
 247                         }
 248                         __ino_to_path_fd(inum, path_fd, verbose, full_path);
 249                         if (path_fd != fd)
 250                                 close_file_or_dir(path_fd, dirs);
 251                 } else {
 252                         printf("inode %llu offset %llu root %llu\n", inum,
 253                                 offset, root);
 254                 }
 255         }
 256
 257 out:
 258         close_file_or_dir(fd, dirstream);
 259         free(inodes);
 260         return !!ret;
 261 }
 262
 263 static const char * const cmd_inspect_subvolid_resolve_usage[] = {
 264         "btrfs inspect-internal subvolid-resolve <subvolid> <path>",
 265         "Get file system paths for the given subvolume ID.",
 266         NULL
 267 };
 268
 269 static int cmd_inspect_subvolid_resolve(int argc, char **argv)
 270 {
 271         int ret;
 272         int fd = -1;
 273         u64 subvol_id;
 274         char path[PATH_MAX];
 275         DIR *dirstream = NULL;
 276
 277         clean_args_no_options(argc, argv, cmd_inspect_subvolid_resolve_usage);
 278
 279         if (check_argc_exact(argc - optind, 2))
 280                 usage(cmd_inspect_subvolid_resolve_usage);
 281
 282         fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
 283         if (fd < 0) {
 284                 ret = -ENOENT;
 285                 goto out;
 286         }
 287
 288         subvol_id = arg_strtou64(argv[optind]);
 289         ret = btrfs_subvolid_resolve(fd, path, sizeof(path), subvol_id);
 290
 291         if (ret) {
 292                 error("resolving subvolid %llu error %d",
 293                         (unsigned long long)subvol_id, ret);
 294                 goto out;
 295         }
 296
 297         path[PATH_MAX - 1] = '\0';
 298         printf("%s\n", path);
 299
 300 out:
 301         close_file_or_dir(fd, dirstream);
 302         return !!ret;
 303 }
 304
 305 static const char* const cmd_inspect_rootid_usage[] = {
 306         "btrfs inspect-internal rootid <path>",
 307         "Get tree ID of the containing subvolume of path.",
 308         NULL
 309 };
 310
 311 static int cmd_inspect_rootid(int argc, char **argv)
 312 {
 313         int ret;
 314         int fd = -1;
 315         u64 rootid;
 316         DIR *dirstream = NULL;
 317
 318         clean_args_no_options(argc, argv, cmd_inspect_rootid_usage);
 319
 320         if (check_argc_exact(argc - optind, 1))
 321                 usage(cmd_inspect_rootid_usage);
 322
 323         fd = btrfs_open_file_or_dir(argv[optind], &dirstream, 1);
 324         if (fd < 0) {
 325                 ret = -ENOENT;
 326                 goto out;
 327         }
 328
 329         ret = lookup_path_rootid(fd, &rootid);
 330         if (ret) {
 331                 error("failed to lookup root id: %s", strerror(-ret));
 332                 goto out;
 333         }
 334
 335         printf("%llu\n", (unsigned long long)rootid);
 336 out:
 337         close_file_or_dir(fd, dirstream);
 338
 339         return !!ret;
 340 }
 341
 342 static const char* const cmd_inspect_min_dev_size_usage[] = {
 343         "btrfs inspect-internal min-dev-size [options] <path>",
 344         "Get the minimum size the device can be shrunk to. The",
 345         "device id 1 is used by default.",
 346         "--id DEVID   specify the device id to query",
 347         NULL
 348 };
 349
 350 struct dev_extent_elem {
 351         u64 start;
 352         /* inclusive end */
 353         u64 end;
 354         struct list_head list;
 355 };
 356
 357 static int add_dev_extent(struct list_head *list,
 358                           const u64 start, const u64 end,
 359                           const int append)
 360 {
 361         struct dev_extent_elem *e;
 362
 363         e = malloc(sizeof(*e));
 364         if (!e)
 365                 return -ENOMEM;
 366
 367         e->start = start;
 368         e->end = end;
 369
 370         if (append)
 371                 list_add_tail(&e->list, list);
 372         else
 373                 list_add(&e->list, list);
 374
 375         return 0;
 376 }
 377
 378 static void free_dev_extent_list(struct list_head *list)
 379 {
 380         while (!list_empty(list)) {
 381                 struct dev_extent_elem *e;
 382
 383                 e = list_first_entry(list, struct dev_extent_elem, list);
 384                 list_del(&e->list);
 385                 free(e);
 386         }
 387 }
 388
 389 static int hole_includes_sb_mirror(const u64 start, const u64 end)
 390 {
 391         int i;
 392         int ret = 0;
 393
 394         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
 395                 u64 bytenr = btrfs_sb_offset(i);
 396
 397                 if (bytenr >= start && bytenr <= end) {
 398                         ret = 1;
 399                         break;
 400                 }
 401         }
 402
 403         return ret;
 404 }
 405
 406 static void adjust_dev_min_size(struct list_head *extents,
 407                                 struct list_head *holes,
 408                                 u64 *min_size)
 409 {
 410         /*
 411          * If relocation of the block group of a device extent must happen (see
 412          * below) scratch space is used for the relocation. So track here the
 413          * size of the largest device extent that has to be relocated. We track
 414          * only the largest and not the sum of the sizes of all relocated block
 415          * groups because after each block group is relocated the running
 416          * transaction is committed so that pinned space is released.
 417          */
 418         u64 scratch_space = 0;
 419
 420         /*
 421          * List of device extents is sorted by descending order of the extent's
 422          * end offset. If some extent goes beyond the computed minimum size,
 423          * which initially matches the sum of the lengths of all extents,
 424          * we need to check if the extent can be relocated to an hole in the
 425          * device between [0, *min_size[ (which is what the resize ioctl does).
 426          */
 427         while (!list_empty(extents)) {
 428                 struct dev_extent_elem *e;
 429                 struct dev_extent_elem *h;
 430                 int found = 0;
 431                 u64 extent_len;
 432                 u64 hole_len = 0;
 433
 434                 e = list_first_entry(extents, struct dev_extent_elem, list);
 435                 if (e->end <= *min_size)
 436                         break;
 437
 438                 /*
 439                  * Our extent goes beyond the computed *min_size. See if we can
 440                  * find a hole large enough to relocate it to. If not we must stop
 441                  * and set *min_size to the end of the extent.
 442                  */
 443                 extent_len = e->end - e->start + 1;
 444                 list_for_each_entry(h, holes, list) {
 445                         hole_len = h->end - h->start + 1;
 446                         if (hole_len >= extent_len) {
 447                                 found = 1;
 448                                 break;
 449                         }
 450                 }
 451
 452                 if (!found) {
 453                         *min_size = e->end + 1;
 454                         break;
 455                 }
 456
 457                 /*
 458                  * If the hole found contains the location for a superblock
 459                  * mirror, we are pessimistic and require allocating one
 460                  * more extent of the same size. This is because the block
 461                  * group could be in the worst case used by a single extent
 462                  * with a size >= (block_group.length - superblock.size).
 463                  */
 464                 if (hole_includes_sb_mirror(h->start,
 465                                             h->start + extent_len - 1))
 466                         *min_size += extent_len;
 467
 468                 if (hole_len > extent_len) {
 469                         h->start += extent_len;
 470                 } else {
 471                         list_del(&h->list);
 472                         free(h);
 473                 }
 474
 475                 list_del(&e->list);
 476                 free(e);
 477
 478                 if (extent_len > scratch_space)
 479                         scratch_space = extent_len;
 480         }
 481
 482         if (scratch_space) {
 483                 *min_size += scratch_space;
 484                 /*
 485                  * Chunk allocation requires inserting/updating items in the
 486                  * chunk tree, so often this can lead to the need of allocating
 487                  * a new system chunk too, which has a maximum size of 32Mb.
 488                  */
 489                 *min_size += SZ_32M;
 490         }
 491 }
 492
 493 static int print_min_dev_size(int fd, u64 devid)
 494 {
 495         int ret = 1;
 496         /*
 497          * Device allocations starts at 1Mb or at the value passed through the
 498          * mount option alloc_start if it's bigger than 1Mb. The alloc_start
 499          * option is used for debugging and testing only, and recently the
 500          * possibility of deprecating/removing it has been discussed, so we
 501          * ignore it here.
 502          */
 503         u64 min_size = SZ_1M;
 504         struct btrfs_ioctl_search_args args;
 505         struct btrfs_ioctl_search_key *sk = &args.key;
 506         u64 last_pos = (u64)-1;
 507         LIST_HEAD(extents);
 508         LIST_HEAD(holes);
 509
 510         memset(&args, 0, sizeof(args));
 511         sk->tree_id = BTRFS_DEV_TREE_OBJECTID;
 512         sk->min_objectid = devid;
 513         sk->max_objectid = devid;
 514         sk->max_type = BTRFS_DEV_EXTENT_KEY;
 515         sk->min_type = BTRFS_DEV_EXTENT_KEY;
 516         sk->min_offset = 0;
 517         sk->max_offset = (u64)-1;
 518         sk->min_transid = 0;
 519         sk->max_transid = (u64)-1;
 520         sk->nr_items = 4096;
 521
 522         while (1) {
 523                 int i;
 524                 struct btrfs_ioctl_search_header *sh;
 525                 unsigned long off = 0;
 526
 527                 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
 528                 if (ret < 0) {
 529                         error("tree search ioctl: %m");
 530                         ret = 1;
 531                         goto out;
 532                 }
 533
 534                 if (sk->nr_items == 0)
 535                         break;
 536
 537                 for (i = 0; i < sk->nr_items; i++) {
 538                         struct btrfs_dev_extent *extent;
 539                         u64 len;
 540
 541                         sh = (struct btrfs_ioctl_search_header *)(args.buf +
 542                                                                   off);
 543                         off += sizeof(*sh);
 544                         extent = (struct btrfs_dev_extent *)(args.buf + off);
 545                         off += btrfs_search_header_len(sh);
 546
 547                         sk->min_objectid = btrfs_search_header_objectid(sh);
 548                         sk->min_type = btrfs_search_header_type(sh);
 549                         sk->min_offset = btrfs_search_header_offset(sh) + 1;
 550
 551                         if (btrfs_search_header_objectid(sh) != devid ||
 552                             btrfs_search_header_type(sh) != BTRFS_DEV_EXTENT_KEY)
 553                                 continue;
 554
 555                         len = btrfs_stack_dev_extent_length(extent);
 556                         min_size += len;
 557                         ret = add_dev_extent(&extents,
 558                                 btrfs_search_header_offset(sh),
 559                                 btrfs_search_header_offset(sh) + len - 1, 0);
 560
 561                         if (!ret && last_pos != (u64)-1 &&
 562                             last_pos != btrfs_search_header_offset(sh))
 563                                 ret = add_dev_extent(&holes, last_pos,
 564                                         btrfs_search_header_offset(sh) - 1, 1);
 565                         if (ret) {
 566                                 error("add device extent: %s", strerror(-ret));
 567                                 ret = 1;
 568                                 goto out;
 569                         }
 570
 571                         last_pos = btrfs_search_header_offset(sh) + len;
 572                 }
 573
 574                 if (sk->min_type != BTRFS_DEV_EXTENT_KEY ||
 575                     sk->min_objectid != devid)
 576                         break;
 577         }
 578
 579         adjust_dev_min_size(&extents, &holes, &min_size);
 580         printf("%llu bytes (%s)\n", min_size, pretty_size(min_size));
 581         ret = 0;
 582 out:
 583         free_dev_extent_list(&extents);
 584         free_dev_extent_list(&holes);
 585
 586         return ret;
 587 }
 588
 589 static int cmd_inspect_min_dev_size(int argc, char **argv)
 590 {
 591         int ret;
 592         int fd = -1;
 593         DIR *dirstream = NULL;
 594         u64 devid = 1;
 595
 596         optind = 0;
 597         while (1) {
 598                 int c;
 599                 enum { GETOPT_VAL_DEVID = 256 };
 600                 static const struct option long_options[] = {
 601                         { "id", required_argument, NULL, GETOPT_VAL_DEVID },
 602                         {NULL, 0, NULL, 0}
 603                 };
 604
 605                 c = getopt_long(argc, argv, "", long_options, NULL);
 606                 if (c < 0)
 607                         break;
 608
 609                 switch (c) {
 610                 case GETOPT_VAL_DEVID:
 611                         devid = arg_strtou64(optarg);
 612                         break;
 613                 default:
 614                         usage(cmd_inspect_min_dev_size_usage);
 615                 }
 616         }
 617         if (check_argc_exact(argc - optind, 1))
 618                 usage(cmd_inspect_min_dev_size_usage);
 619
 620         fd = btrfs_open_dir(argv[optind], &dirstream, 1);
 621         if (fd < 0) {
 622                 ret = -ENOENT;
 623                 goto out;
 624         }
 625
 626         ret = print_min_dev_size(fd, devid);
 627         close_file_or_dir(fd, dirstream);
 628 out:
 629         return !!ret;
 630 }
 631
 632 static const char inspect_cmd_group_info[] =
 633 "query various internal information";
 634
 635 const struct cmd_group inspect_cmd_group = {
 636         inspect_cmd_group_usage, inspect_cmd_group_info, {
 637                 { "inode-resolve", cmd_inspect_inode_resolve,
 638                         cmd_inspect_inode_resolve_usage, NULL, 0 },
 639                 { "logical-resolve", cmd_inspect_logical_resolve,
 640                         cmd_inspect_logical_resolve_usage, NULL, 0 },
 641                 { "subvolid-resolve", cmd_inspect_subvolid_resolve,
 642                         cmd_inspect_subvolid_resolve_usage, NULL, 0 },
 643                 { "rootid", cmd_inspect_rootid, cmd_inspect_rootid_usage, NULL,
 644                         0 },
 645                 { "min-dev-size", cmd_inspect_min_dev_size,
 646                         cmd_inspect_min_dev_size_usage, NULL, 0 },
 647                 { "dump-tree", cmd_inspect_dump_tree,
 648                                 cmd_inspect_dump_tree_usage, NULL, 0 },
 649                 { "dump-super", cmd_inspect_dump_super,
 650                                 cmd_inspect_dump_super_usage, NULL, 0 },
 651                 { "tree-stats", cmd_inspect_tree_stats,
 652                                 cmd_inspect_tree_stats_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 }