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         while (1) {
  98                 int c = getopt(argc, argv, "v");
  99                 if (c < 0)
 100                         break;
 101
 102                 switch (c) {
 103                 case 'v':
 104                         verbose = 1;
 105                         break;
 106                 default:
 107                         usage(cmd_inspect_inode_resolve_usage);
 108                 }
 109         }
 110
 111         if (check_argc_exact(argc - optind, 2))
 112                 usage(cmd_inspect_inode_resolve_usage);
 113
 114         fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
 115         if (fd < 0)
 116                 return 1;
 117
 118         ret = __ino_to_path_fd(arg_strtou64(argv[optind]), fd, verbose,
 119                                argv[optind+1]);
 120         close_file_or_dir(fd, dirstream);
 121         return !!ret;
 122
 123 }
 124
 125 static const char * const cmd_inspect_logical_resolve_usage[] = {
 126         "btrfs inspect-internal logical-resolve [-Pv] [-s bufsize] <logical> <path>",
 127         "Get file system paths for the given logical address",
 128         "-P          skip the path resolving and print the inodes instead",
 129         "-v          verbose mode",
 130         "-s bufsize  set inode container's size. This is used to increase inode",
 131         "            container's size in case it is not enough to read all the ",
 132         "            resolved results. The max value one can set is 64k",
 133         NULL
 134 };
 135
 136 static int cmd_inspect_logical_resolve(int argc, char **argv)
 137 {
 138         int ret;
 139         int fd;
 140         int i;
 141         int verbose = 0;
 142         int getpath = 1;
 143         int bytes_left;
 144         struct btrfs_ioctl_logical_ino_args loi;
 145         struct btrfs_data_container *inodes;
 146         u64 size = 4096;
 147         char full_path[PATH_MAX];
 148         char *path_ptr;
 149         DIR *dirstream = NULL;
 150
 151         while (1) {
 152                 int c = getopt(argc, argv, "Pvs:");
 153                 if (c < 0)
 154                         break;
 155
 156                 switch (c) {
 157                 case 'P':
 158                         getpath = 0;
 159                         break;
 160                 case 'v':
 161                         verbose = 1;
 162                         break;
 163                 case 's':
 164                         size = arg_strtou64(optarg);
 165                         break;
 166                 default:
 167                         usage(cmd_inspect_logical_resolve_usage);
 168                 }
 169         }
 170
 171         if (check_argc_exact(argc - optind, 2))
 172                 usage(cmd_inspect_logical_resolve_usage);
 173
 174         size = min(size, (u64)SZ_64K);
 175         inodes = malloc(size);
 176         if (!inodes)
 177                 return 1;
 178
 179         memset(inodes, 0, sizeof(*inodes));
 180         loi.logical = arg_strtou64(argv[optind]);
 181         loi.size = size;
 182         loi.inodes = ptr_to_u64(inodes);
 183
 184         fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
 185         if (fd < 0) {
 186                 ret = 12;
 187                 goto out;
 188         }
 189
 190         ret = ioctl(fd, BTRFS_IOC_LOGICAL_INO, &loi);
 191         if (ret < 0) {
 192                 error("logical ino ioctl: %m");
 193                 goto out;
 194         }
 195
 196         if (verbose)
 197                 printf("ioctl ret=%d, total_size=%llu, bytes_left=%lu, "
 198                         "bytes_missing=%lu, cnt=%d, missed=%d\n",
 199                         ret, size,
 200                         (unsigned long)inodes->bytes_left,
 201                         (unsigned long)inodes->bytes_missing,
 202                         inodes->elem_cnt, inodes->elem_missed);
 203
 204         bytes_left = sizeof(full_path);
 205         ret = snprintf(full_path, bytes_left, "%s/", argv[optind+1]);
 206         path_ptr = full_path + ret;
 207         bytes_left -= ret + 1;
 208         if (bytes_left < 0) {
 209                 error("path buffer too small: %d bytes", bytes_left);
 210                 goto out;
 211         }
 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                                 free(name);
 235                                 if (ret >= bytes_left) {
 236                                         error("path buffer too small: %d bytes",
 237                                                         bytes_left - ret);
 238                                         goto out;
 239                                 }
 240                                 path_fd = btrfs_open_dir(full_path, &dirs, 1);
 241                                 if (path_fd < 0) {
 242                                         ret = -ENOENT;
 243                                         goto out;
 244                                 }
 245                         }
 246                         __ino_to_path_fd(inum, path_fd, verbose, full_path);
 247                         if (path_fd != fd)
 248                                 close_file_or_dir(path_fd, dirs);
 249                 } else {
 250                         printf("inode %llu offset %llu root %llu\n", inum,
 251                                 offset, root);
 252                 }
 253         }
 254
 255 out:
 256         close_file_or_dir(fd, dirstream);
 257         free(inodes);
 258         return !!ret;
 259 }
 260
 261 static const char * const cmd_inspect_subvolid_resolve_usage[] = {
 262         "btrfs inspect-internal subvolid-resolve <subvolid> <path>",
 263         "Get file system paths for the given subvolume ID.",
 264         NULL
 265 };
 266
 267 static int cmd_inspect_subvolid_resolve(int argc, char **argv)
 268 {
 269         int ret;
 270         int fd = -1;
 271         u64 subvol_id;
 272         char path[PATH_MAX];
 273         DIR *dirstream = NULL;
 274
 275         clean_args_no_options(argc, argv, cmd_inspect_subvolid_resolve_usage);
 276
 277         if (check_argc_exact(argc - optind, 2))
 278                 usage(cmd_inspect_subvolid_resolve_usage);
 279
 280         fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
 281         if (fd < 0) {
 282                 ret = -ENOENT;
 283                 goto out;
 284         }
 285
 286         subvol_id = arg_strtou64(argv[optind]);
 287         ret = btrfs_subvolid_resolve(fd, path, sizeof(path), subvol_id);
 288
 289         if (ret) {
 290                 error("resolving subvolid %llu error %d",
 291                         (unsigned long long)subvol_id, ret);
 292                 goto out;
 293         }
 294
 295         path[PATH_MAX - 1] = '\0';
 296         printf("%s\n", path);
 297
 298 out:
 299         close_file_or_dir(fd, dirstream);
 300         return !!ret;
 301 }
 302
 303 static const char* const cmd_inspect_rootid_usage[] = {
 304         "btrfs inspect-internal rootid <path>",
 305         "Get tree ID of the containing subvolume of path.",
 306         NULL
 307 };
 308
 309 static int cmd_inspect_rootid(int argc, char **argv)
 310 {
 311         int ret;
 312         int fd = -1;
 313         u64 rootid;
 314         DIR *dirstream = NULL;
 315
 316         clean_args_no_options(argc, argv, cmd_inspect_rootid_usage);
 317
 318         if (check_argc_exact(argc - optind, 1))
 319                 usage(cmd_inspect_rootid_usage);
 320
 321         fd = btrfs_open_file_or_dir(argv[optind], &dirstream, 1);
 322         if (fd < 0) {
 323                 ret = -ENOENT;
 324                 goto out;
 325         }
 326
 327         ret = lookup_path_rootid(fd, &rootid);
 328         if (ret) {
 329                 error("failed to lookup root id: %s", strerror(-ret));
 330                 goto out;
 331         }
 332
 333         printf("%llu\n", (unsigned long long)rootid);
 334 out:
 335         close_file_or_dir(fd, dirstream);
 336
 337         return !!ret;
 338 }
 339
 340 static const char* const cmd_inspect_min_dev_size_usage[] = {
 341         "btrfs inspect-internal min-dev-size [options] <path>",
 342         "Get the minimum size the device can be shrunk to. The",
 343         "device id 1 is used by default.",
 344         "--id DEVID   specify the device id to query",
 345         NULL
 346 };
 347
 348 struct dev_extent_elem {
 349         u64 start;
 350         /* inclusive end */
 351         u64 end;
 352         struct list_head list;
 353 };
 354
 355 static int add_dev_extent(struct list_head *list,
 356                           const u64 start, const u64 end,
 357                           const int append)
 358 {
 359         struct dev_extent_elem *e;
 360
 361         e = malloc(sizeof(*e));
 362         if (!e)
 363                 return -ENOMEM;
 364
 365         e->start = start;
 366         e->end = end;
 367
 368         if (append)
 369                 list_add_tail(&e->list, list);
 370         else
 371                 list_add(&e->list, list);
 372
 373         return 0;
 374 }
 375
 376 static void free_dev_extent_list(struct list_head *list)
 377 {
 378         while (!list_empty(list)) {
 379                 struct dev_extent_elem *e;
 380
 381                 e = list_first_entry(list, struct dev_extent_elem, list);
 382                 list_del(&e->list);
 383                 free(e);
 384         }
 385 }
 386
 387 static int hole_includes_sb_mirror(const u64 start, const u64 end)
 388 {
 389         int i;
 390         int ret = 0;
 391
 392         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
 393                 u64 bytenr = btrfs_sb_offset(i);
 394
 395                 if (bytenr >= start && bytenr <= end) {
 396                         ret = 1;
 397                         break;
 398                 }
 399         }
 400
 401         return ret;
 402 }
 403
 404 static void adjust_dev_min_size(struct list_head *extents,
 405                                 struct list_head *holes,
 406                                 u64 *min_size)
 407 {
 408         /*
 409          * If relocation of the block group of a device extent must happen (see
 410          * below) scratch space is used for the relocation. So track here the
 411          * size of the largest device extent that has to be relocated. We track
 412          * only the largest and not the sum of the sizes of all relocated block
 413          * groups because after each block group is relocated the running
 414          * transaction is committed so that pinned space is released.
 415          */
 416         u64 scratch_space = 0;
 417
 418         /*
 419          * List of device extents is sorted by descending order of the extent's
 420          * end offset. If some extent goes beyond the computed minimum size,
 421          * which initially matches the sum of the lengths of all extents,
 422          * we need to check if the extent can be relocated to an hole in the
 423          * device between [0, *min_size[ (which is what the resize ioctl does).
 424          */
 425         while (!list_empty(extents)) {
 426                 struct dev_extent_elem *e;
 427                 struct dev_extent_elem *h;
 428                 int found = 0;
 429                 u64 extent_len;
 430                 u64 hole_len = 0;
 431
 432                 e = list_first_entry(extents, struct dev_extent_elem, list);
 433                 if (e->end <= *min_size)
 434                         break;
 435
 436                 /*
 437                  * Our extent goes beyond the computed *min_size. See if we can
 438                  * find a hole large enough to relocate it to. If not we must stop
 439                  * and set *min_size to the end of the extent.
 440                  */
 441                 extent_len = e->end - e->start + 1;
 442                 list_for_each_entry(h, holes, list) {
 443                         hole_len = h->end - h->start + 1;
 444                         if (hole_len >= extent_len) {
 445                                 found = 1;
 446                                 break;
 447                         }
 448                 }
 449
 450                 if (!found) {
 451                         *min_size = e->end + 1;
 452                         break;
 453                 }
 454
 455                 /*
 456                  * If the hole found contains the location for a superblock
 457                  * mirror, we are pessimistic and require allocating one
 458                  * more extent of the same size. This is because the block
 459                  * group could be in the worst case used by a single extent
 460                  * with a size >= (block_group.length - superblock.size).
 461                  */
 462                 if (hole_includes_sb_mirror(h->start,
 463                                             h->start + extent_len - 1))
 464                         *min_size += extent_len;
 465
 466                 if (hole_len > extent_len) {
 467                         h->start += extent_len;
 468                 } else {
 469                         list_del(&h->list);
 470                         free(h);
 471                 }
 472
 473                 list_del(&e->list);
 474                 free(e);
 475
 476                 if (extent_len > scratch_space)
 477                         scratch_space = extent_len;
 478         }
 479
 480         if (scratch_space) {
 481                 *min_size += scratch_space;
 482                 /*
 483                  * Chunk allocation requires inserting/updating items in the
 484                  * chunk tree, so often this can lead to the need of allocating
 485                  * a new system chunk too, which has a maximum size of 32Mb.
 486                  */
 487                 *min_size += SZ_32M;
 488         }
 489 }
 490
 491 static int print_min_dev_size(int fd, u64 devid)
 492 {
 493         int ret = 1;
 494         /*
 495          * Device allocations starts at 1Mb or at the value passed through the
 496          * mount option alloc_start if it's bigger than 1Mb. The alloc_start
 497          * option is used for debugging and testing only, and recently the
 498          * possibility of deprecating/removing it has been discussed, so we
 499          * ignore it here.
 500          */
 501         u64 min_size = SZ_1M;
 502         struct btrfs_ioctl_search_args args;
 503         struct btrfs_ioctl_search_key *sk = &args.key;
 504         u64 last_pos = (u64)-1;
 505         LIST_HEAD(extents);
 506         LIST_HEAD(holes);
 507
 508         memset(&args, 0, sizeof(args));
 509         sk->tree_id = BTRFS_DEV_TREE_OBJECTID;
 510         sk->min_objectid = devid;
 511         sk->max_objectid = devid;
 512         sk->max_type = BTRFS_DEV_EXTENT_KEY;
 513         sk->min_type = BTRFS_DEV_EXTENT_KEY;
 514         sk->min_offset = 0;
 515         sk->max_offset = (u64)-1;
 516         sk->min_transid = 0;
 517         sk->max_transid = (u64)-1;
 518         sk->nr_items = 4096;
 519
 520         while (1) {
 521                 int i;
 522                 struct btrfs_ioctl_search_header *sh;
 523                 unsigned long off = 0;
 524
 525                 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
 526                 if (ret < 0) {
 527                         error("tree search ioctl: %m");
 528                         ret = 1;
 529                         goto out;
 530                 }
 531
 532                 if (sk->nr_items == 0)
 533                         break;
 534
 535                 for (i = 0; i < sk->nr_items; i++) {
 536                         struct btrfs_dev_extent *extent;
 537                         u64 len;
 538
 539                         sh = (struct btrfs_ioctl_search_header *)(args.buf +
 540                                                                   off);
 541                         off += sizeof(*sh);
 542                         extent = (struct btrfs_dev_extent *)(args.buf + off);
 543                         off += btrfs_search_header_len(sh);
 544
 545                         sk->min_objectid = btrfs_search_header_objectid(sh);
 546                         sk->min_type = btrfs_search_header_type(sh);
 547                         sk->min_offset = btrfs_search_header_offset(sh) + 1;
 548
 549                         if (btrfs_search_header_objectid(sh) != devid ||
 550                             btrfs_search_header_type(sh) != BTRFS_DEV_EXTENT_KEY)
 551                                 continue;
 552
 553                         len = btrfs_stack_dev_extent_length(extent);
 554                         min_size += len;
 555                         ret = add_dev_extent(&extents,
 556                                 btrfs_search_header_offset(sh),
 557                                 btrfs_search_header_offset(sh) + len - 1, 0);
 558
 559                         if (!ret && last_pos != (u64)-1 &&
 560                             last_pos != btrfs_search_header_offset(sh))
 561                                 ret = add_dev_extent(&holes, last_pos,
 562                                         btrfs_search_header_offset(sh) - 1, 1);
 563                         if (ret) {
 564                                 error("add device extent: %s", strerror(-ret));
 565                                 ret = 1;
 566                                 goto out;
 567                         }
 568
 569                         last_pos = btrfs_search_header_offset(sh) + len;
 570                 }
 571
 572                 if (sk->min_type != BTRFS_DEV_EXTENT_KEY ||
 573                     sk->min_objectid != devid)
 574                         break;
 575         }
 576
 577         adjust_dev_min_size(&extents, &holes, &min_size);
 578         printf("%llu bytes (%s)\n", min_size, pretty_size(min_size));
 579         ret = 0;
 580 out:
 581         free_dev_extent_list(&extents);
 582         free_dev_extent_list(&holes);
 583
 584         return ret;
 585 }
 586
 587 static int cmd_inspect_min_dev_size(int argc, char **argv)
 588 {
 589         int ret;
 590         int fd = -1;
 591         DIR *dirstream = NULL;
 592         u64 devid = 1;
 593
 594         while (1) {
 595                 int c;
 596                 enum { GETOPT_VAL_DEVID = 256 };
 597                 static const struct option long_options[] = {
 598                         { "id", required_argument, NULL, GETOPT_VAL_DEVID },
 599                         {NULL, 0, NULL, 0}
 600                 };
 601
 602                 c = getopt_long(argc, argv, "", long_options, NULL);
 603                 if (c < 0)
 604                         break;
 605
 606                 switch (c) {
 607                 case GETOPT_VAL_DEVID:
 608                         devid = arg_strtou64(optarg);
 609                         break;
 610                 default:
 611                         usage(cmd_inspect_min_dev_size_usage);
 612                 }
 613         }
 614         if (check_argc_exact(argc - optind, 1))
 615                 usage(cmd_inspect_min_dev_size_usage);
 616
 617         fd = btrfs_open_dir(argv[optind], &dirstream, 1);
 618         if (fd < 0) {
 619                 ret = -ENOENT;
 620                 goto out;
 621         }
 622
 623         ret = print_min_dev_size(fd, devid);
 624         close_file_or_dir(fd, dirstream);
 625 out:
 626         return !!ret;
 627 }
 628
 629 static const char inspect_cmd_group_info[] =
 630 "query various internal information";
 631
 632 const struct cmd_group inspect_cmd_group = {
 633         inspect_cmd_group_usage, inspect_cmd_group_info, {
 634                 { "inode-resolve", cmd_inspect_inode_resolve,
 635                         cmd_inspect_inode_resolve_usage, NULL, 0 },
 636                 { "logical-resolve", cmd_inspect_logical_resolve,
 637                         cmd_inspect_logical_resolve_usage, NULL, 0 },
 638                 { "subvolid-resolve", cmd_inspect_subvolid_resolve,
 639                         cmd_inspect_subvolid_resolve_usage, NULL, 0 },
 640                 { "rootid", cmd_inspect_rootid, cmd_inspect_rootid_usage, NULL,
 641                         0 },
 642                 { "min-dev-size", cmd_inspect_min_dev_size,
 643                         cmd_inspect_min_dev_size_usage, NULL, 0 },
 644                 { "dump-tree", cmd_inspect_dump_tree,
 645                                 cmd_inspect_dump_tree_usage, NULL, 0 },
 646                 { "dump-super", cmd_inspect_dump_super,
 647                                 cmd_inspect_dump_super_usage, NULL, 0 },
 648                 { "tree-stats", cmd_inspect_tree_stats,
 649                                 cmd_inspect_tree_stats_usage, NULL, 0 },
 650                 NULL_CMD_STRUCT
 651         }
 652 };
 653
 654 int cmd_inspect(int argc, char **argv)
 655 {
 656         return handle_command_group(&inspect_cmd_group, argc, argv);
 657 }