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