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
  38 static const char * const inspect_cmd_group_usage[] = {
  39         "btrfs inspect-internal <command> <args>",
  40         NULL
  41 };
  42
  43 static int __ino_to_path_fd(u64 inum, int fd, int verbose, const char *prepend)
  44 {
  45         int ret;
  46         int i;
  47         struct btrfs_ioctl_ino_path_args ipa;
  48         struct btrfs_data_container fspath[PATH_MAX];
  49
  50         memset(fspath, 0, sizeof(*fspath));
  51         ipa.inum = inum;
  52         ipa.size = PATH_MAX;
  53         ipa.fspath = ptr_to_u64(fspath);
  54
  55         ret = ioctl(fd, BTRFS_IOC_INO_PATHS, &ipa);
  56         if (ret < 0) {
  57                 error("ino paths ioctl: %s", strerror(errno));
  58                 goto out;
  59         }
  60
  61         if (verbose)
  62                 printf("ioctl ret=%d, bytes_left=%lu, bytes_missing=%lu, "
  63                         "cnt=%d, missed=%d\n", ret,
  64                         (unsigned long)fspath->bytes_left,
  65                         (unsigned long)fspath->bytes_missing,
  66                         fspath->elem_cnt, fspath->elem_missed);
  67
  68         for (i = 0; i < fspath->elem_cnt; ++i) {
  69                 u64 ptr;
  70                 char *str;
  71                 ptr = (u64)(unsigned long)fspath->val;
  72                 ptr += fspath->val[i];
  73                 str = (char *)(unsigned long)ptr;
  74                 if (prepend)
  75                         printf("%s/%s\n", prepend, str);
  76                 else
  77                         printf("%s\n", str);
  78         }
  79
  80 out:
  81         return !!ret;
  82 }
  83
  84 static const char * const cmd_inspect_inode_resolve_usage[] = {
  85         "btrfs inspect-internal inode-resolve [-v] <inode> <path>",
  86         "Get file system paths for the given inode",
  87         "",
  88         "-v   verbose mode",
  89         NULL
  90 };
  91
  92 static int cmd_inspect_inode_resolve(int argc, char **argv)
  93 {
  94         int fd;
  95         int verbose = 0;
  96         int ret;
  97         DIR *dirstream = NULL;
  98
  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         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)64 * 1024);
 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: %s", strerror(errno));
 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         BUG_ON(bytes_left < 0);
 211
 212         for (i = 0; i < inodes->elem_cnt; i += 3) {
 213                 u64 inum = inodes->val[i];
 214                 u64 offset = inodes->val[i+1];
 215                 u64 root = inodes->val[i+2];
 216                 int path_fd;
 217                 char *name;
 218                 DIR *dirs = NULL;
 219
 220                 if (getpath) {
 221                         name = btrfs_list_path_for_root(fd, root);
 222                         if (IS_ERR(name)) {
 223                                 ret = PTR_ERR(name);
 224                                 goto out;
 225                         }
 226                         if (!name) {
 227                                 path_ptr[-1] = '\0';
 228                                 path_fd = fd;
 229                         } else {
 230                                 path_ptr[-1] = '/';
 231                                 ret = snprintf(path_ptr, bytes_left, "%s",
 232                                                 name);
 233                                 BUG_ON(ret >= bytes_left);
 234                                 free(name);
 235                                 path_fd = btrfs_open_dir(full_path, &dirs, 1);
 236                                 if (path_fd < 0) {
 237                                         ret = -ENOENT;
 238                                         goto out;
 239                                 }
 240                         }
 241                         __ino_to_path_fd(inum, path_fd, verbose, full_path);
 242                         if (path_fd != fd)
 243                                 close_file_or_dir(path_fd, dirs);
 244                 } else {
 245                         printf("inode %llu offset %llu root %llu\n", inum,
 246                                 offset, root);
 247                 }
 248         }
 249
 250 out:
 251         close_file_or_dir(fd, dirstream);
 252         free(inodes);
 253         return !!ret;
 254 }
 255
 256 static const char * const cmd_inspect_subvolid_resolve_usage[] = {
 257         "btrfs inspect-internal subvolid-resolve <subvolid> <path>",
 258         "Get file system paths for the given subvolume ID.",
 259         NULL
 260 };
 261
 262 static int cmd_inspect_subvolid_resolve(int argc, char **argv)
 263 {
 264         int ret;
 265         int fd = -1;
 266         u64 subvol_id;
 267         char path[PATH_MAX];
 268         DIR *dirstream = NULL;
 269
 270         clean_args_no_options(argc, argv, cmd_inspect_subvolid_resolve_usage);
 271
 272         if (check_argc_exact(argc - optind, 2))
 273                 usage(cmd_inspect_subvolid_resolve_usage);
 274
 275         fd = btrfs_open_dir(argv[optind + 1], &dirstream, 1);
 276         if (fd < 0) {
 277                 ret = -ENOENT;
 278                 goto out;
 279         }
 280
 281         subvol_id = arg_strtou64(argv[optind]);
 282         ret = btrfs_subvolid_resolve(fd, path, sizeof(path), subvol_id);
 283
 284         if (ret) {
 285                 error("resolving subvolid %llu error %d",
 286                         (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;
 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         clean_args_no_options(argc, argv, cmd_inspect_rootid_usage);
 312
 313         if (check_argc_exact(argc - optind, 1))
 314                 usage(cmd_inspect_rootid_usage);
 315
 316         fd = btrfs_open_dir(argv[optind], &dirstream, 1);
 317         if (fd < 0) {
 318                 ret = -ENOENT;
 319                 goto out;
 320         }
 321
 322         ret = lookup_ino_rootid(fd, &rootid);
 323         if (ret) {
 324                 error("failed to lookup root id: %s", strerror(-ret));
 325                 goto out;
 326         }
 327
 328         printf("%llu\n", (unsigned long long)rootid);
 329 out:
 330         close_file_or_dir(fd, dirstream);
 331
 332         return !!ret;
 333 }
 334
 335 static const char* const cmd_inspect_min_dev_size_usage[] = {
 336         "btrfs inspect-internal min-dev-size [options] <path>",
 337         "Get the minimum size the device can be shrunk to. The",
 338         "device id 1 is used by default.",
 339         "--id DEVID   specify the device id to query",
 340         NULL
 341 };
 342
 343 struct dev_extent_elem {
 344         u64 start;
 345         /* inclusive end */
 346         u64 end;
 347         struct list_head list;
 348 };
 349
 350 static int add_dev_extent(struct list_head *list,
 351                           const u64 start, const u64 end,
 352                           const int append)
 353 {
 354         struct dev_extent_elem *e;
 355
 356         e = malloc(sizeof(*e));
 357         if (!e)
 358                 return -ENOMEM;
 359
 360         e->start = start;
 361         e->end = end;
 362
 363         if (append)
 364                 list_add_tail(&e->list, list);
 365         else
 366                 list_add(&e->list, list);
 367
 368         return 0;
 369 }
 370
 371 static void free_dev_extent_list(struct list_head *list)
 372 {
 373         while (!list_empty(list)) {
 374                 struct dev_extent_elem *e;
 375
 376                 e = list_first_entry(list, struct dev_extent_elem, list);
 377                 list_del(&e->list);
 378                 free(e);
 379         }
 380 }
 381
 382 static int hole_includes_sb_mirror(const u64 start, const u64 end)
 383 {
 384         int i;
 385         int ret = 0;
 386
 387         for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
 388                 u64 bytenr = btrfs_sb_offset(i);
 389
 390                 if (bytenr >= start && bytenr <= end) {
 391                         ret = 1;
 392                         break;
 393                 }
 394         }
 395
 396         return ret;
 397 }
 398
 399 static void adjust_dev_min_size(struct list_head *extents,
 400                                 struct list_head *holes,
 401                                 u64 *min_size)
 402 {
 403         /*
 404          * If relocation of the block group of a device extent must happen (see
 405          * below) scratch space is used for the relocation. So track here the
 406          * size of the largest device extent that has to be relocated. We track
 407          * only the largest and not the sum of the sizes of all relocated block
 408          * groups because after each block group is relocated the running
 409          * transaction is committed so that pinned space is released.
 410          */
 411         u64 scratch_space = 0;
 412
 413         /*
 414          * List of device extents is sorted by descending order of the extent's
 415          * end offset. If some extent goes beyond the computed minimum size,
 416          * which initially matches the sum of the lengths of all extents,
 417          * we need to check if the extent can be relocated to an hole in the
 418          * device between [0, *min_size[ (which is what the resize ioctl does).
 419          */
 420         while (!list_empty(extents)) {
 421                 struct dev_extent_elem *e;
 422                 struct dev_extent_elem *h;
 423                 int found = 0;
 424                 u64 extent_len;
 425                 u64 hole_len = 0;
 426
 427                 e = list_first_entry(extents, struct dev_extent_elem, list);
 428                 if (e->end <= *min_size)
 429                         break;
 430
 431                 /*
 432                  * Our extent goes beyond the computed *min_size. See if we can
 433                  * find a hole large enough to relocate it to. If not we must stop
 434                  * and set *min_size to the end of the extent.
 435                  */
 436                 extent_len = e->end - e->start + 1;
 437                 list_for_each_entry(h, holes, list) {
 438                         hole_len = h->end - h->start + 1;
 439                         if (hole_len >= extent_len) {
 440                                 found = 1;
 441                                 break;
 442                         }
 443                 }
 444
 445                 if (!found) {
 446                         *min_size = e->end + 1;
 447                         break;
 448                 }
 449
 450                 /*
 451                  * If the hole found contains the location for a superblock
 452                  * mirror, we are pessimistic and require allocating one
 453                  * more extent of the same size. This is because the block
 454                  * group could be in the worst case used by a single extent
 455                  * with a size >= (block_group.length - superblock.size).
 456                  */
 457                 if (hole_includes_sb_mirror(h->start,
 458                                             h->start + extent_len - 1))
 459                         *min_size += extent_len;
 460
 461                 if (hole_len > extent_len) {
 462                         h->start += extent_len;
 463                 } else {
 464                         list_del(&h->list);
 465                         free(h);
 466                 }
 467
 468                 list_del(&e->list);
 469                 free(e);
 470
 471                 if (extent_len > scratch_space)
 472                         scratch_space = extent_len;
 473         }
 474
 475         if (scratch_space) {
 476                 *min_size += scratch_space;
 477                 /*
 478                  * Chunk allocation requires inserting/updating items in the
 479                  * chunk tree, so often this can lead to the need of allocating
 480                  * a new system chunk too, which has a maximum size of 32Mb.
 481                  */
 482                 *min_size += 32 * 1024 * 1024;
 483         }
 484 }
 485
 486 static int print_min_dev_size(int fd, u64 devid)
 487 {
 488         int ret = 1;
 489         /*
 490          * Device allocations starts at 1Mb or at the value passed through the
 491          * mount option alloc_start if it's bigger than 1Mb. The alloc_start
 492          * option is used for debugging and testing only, and recently the
 493          * possibility of deprecating/removing it has been discussed, so we
 494          * ignore it here.
 495          */
 496         u64 min_size = 1 * 1024 * 1024ull;
 497         struct btrfs_ioctl_search_args args;
 498         struct btrfs_ioctl_search_key *sk = &args.key;
 499         u64 last_pos = (u64)-1;
 500         LIST_HEAD(extents);
 501         LIST_HEAD(holes);
 502
 503         memset(&args, 0, sizeof(args));
 504         sk->tree_id = BTRFS_DEV_TREE_OBJECTID;
 505         sk->min_objectid = devid;
 506         sk->max_objectid = devid;
 507         sk->max_type = BTRFS_DEV_EXTENT_KEY;
 508         sk->min_type = BTRFS_DEV_EXTENT_KEY;
 509         sk->min_offset = 0;
 510         sk->max_offset = (u64)-1;
 511         sk->min_transid = 0;
 512         sk->max_transid = (u64)-1;
 513         sk->nr_items = 4096;
 514
 515         while (1) {
 516                 int i;
 517                 struct btrfs_ioctl_search_header *sh;
 518                 unsigned long off = 0;
 519
 520                 ret = ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args);
 521                 if (ret < 0) {
 522                         error("tree search ioctl: %s", strerror(errno));
 523                         ret = 1;
 524                         goto out;
 525                 }
 526
 527                 if (sk->nr_items == 0)
 528                         break;
 529
 530                 for (i = 0; i < sk->nr_items; i++) {
 531                         struct btrfs_dev_extent *extent;
 532                         u64 len;
 533
 534                         sh = (struct btrfs_ioctl_search_header *)(args.buf +
 535                                                                   off);
 536                         off += sizeof(*sh);
 537                         extent = (struct btrfs_dev_extent *)(args.buf + off);
 538                         off += btrfs_search_header_len(sh);
 539
 540                         sk->min_objectid = btrfs_search_header_objectid(sh);
 541                         sk->min_type = btrfs_search_header_type(sh);
 542                         sk->min_offset = btrfs_search_header_offset(sh) + 1;
 543
 544                         if (btrfs_search_header_objectid(sh) != devid ||
 545                             btrfs_search_header_type(sh) != BTRFS_DEV_EXTENT_KEY)
 546                                 continue;
 547
 548                         len = btrfs_stack_dev_extent_length(extent);
 549                         min_size += len;
 550                         ret = add_dev_extent(&extents,
 551                                 btrfs_search_header_offset(sh),
 552                                 btrfs_search_header_offset(sh) + len - 1, 0);
 553
 554                         if (!ret && last_pos != (u64)-1 &&
 555                             last_pos != btrfs_search_header_offset(sh))
 556                                 ret = add_dev_extent(&holes, last_pos,
 557                                         btrfs_search_header_offset(sh) - 1, 1);
 558                         if (ret) {
 559                                 error("add device extent: %s", strerror(-ret));
 560                                 ret = 1;
 561                                 goto out;
 562                         }
 563
 564                         last_pos = btrfs_search_header_offset(sh) + 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 const char inspect_cmd_group_info[] =
 625 "query various internal information";
 626
 627 const struct cmd_group inspect_cmd_group = {
 628         inspect_cmd_group_usage, inspect_cmd_group_info, {
 629                 { "inode-resolve", cmd_inspect_inode_resolve,
 630                         cmd_inspect_inode_resolve_usage, NULL, 0 },
 631                 { "logical-resolve", cmd_inspect_logical_resolve,
 632                         cmd_inspect_logical_resolve_usage, NULL, 0 },
 633                 { "subvolid-resolve", cmd_inspect_subvolid_resolve,
 634                         cmd_inspect_subvolid_resolve_usage, NULL, 0 },
 635                 { "rootid", cmd_inspect_rootid, cmd_inspect_rootid_usage, NULL,
 636                         0 },
 637                 { "min-dev-size", cmd_inspect_min_dev_size,
 638                         cmd_inspect_min_dev_size_usage, NULL, 0 },
 639                 { "dump-tree", cmd_inspect_dump_tree,
 640                                 cmd_inspect_dump_tree_usage, NULL, 0 },
 641                 { "dump-super", cmd_inspect_dump_super,
 642                                 cmd_inspect_dump_super_usage, NULL, 0 },
 643                 { "tree-stats", cmd_inspect_tree_stats,
 644                                 cmd_inspect_tree_stats_usage, NULL, 0 },
 645                 NULL_CMD_STRUCT
 646         }
 647 };
 648
 649 int cmd_inspect(int argc, char **argv)
 650 {
 651         return handle_command_group(&inspect_cmd_group, argc, argv);
 652 }