misc/filefrag.c

   1 /*
   2  * filefrag.c -- report if a particular file is fragmented
   3  *
   4  * Copyright 2003 by Theodore Ts'o.
   5  *
   6  * %Begin-Header%
   7  * This file may be redistributed under the terms of the GNU Public
   8  * License.
   9  * %End-Header%
  10  */
  11
  12 #include "config.h"
  13 #ifndef __linux__
  14 #include <stdio.h>
  15 #include <stdlib.h>
  16 #include <unistd.h>
  17
  18 int main(void) {
  19         fputs("This program is only supported on Linux!\n", stderr);
  20         exit(EXIT_FAILURE);
  21 }
  22 #else
  23 #ifndef _LARGEFILE_SOURCE
  24 #define _LARGEFILE_SOURCE
  25 #endif
  26 #ifndef _LARGEFILE64_SOURCE
  27 #define _LARGEFILE64_SOURCE
  28 #endif
  29
  30
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <unistd.h>
  34 #include <string.h>
  35 #include <time.h>
  36 #include <fcntl.h>
  37 #include <errno.h>
  38 #ifdef HAVE_GETOPT_H
  39 #include <getopt.h>
  40 #else
  41 extern char *optarg;
  42 extern int optind;
  43 #endif
  44 #include <sys/types.h>
  45 #include <sys/stat.h>
  46 #include <sys/vfs.h>
  47 #include <sys/ioctl.h>
  48 #include <linux/fd.h>
  49 #include <ext2fs/ext2fs.h>
  50 #include <ext2fs/ext2_types.h>
  51 #include <ext2fs/fiemap.h>
  52
  53 int verbose = 0;
  54 int blocksize;          /* Use specified blocksize (default 1kB) */
  55 int sync_file = 0;      /* fsync file before getting the mapping */
  56 int xattr_map = 0;      /* get xattr mapping */
  57 int force_bmap; /* force use of FIBMAP instead of FIEMAP */
  58 int force_extent;       /* print output in extent format always */
  59 int logical_width = 8;
  60 int physical_width = 10;
  61 const char *ext_fmt = "%4d: %*llu..%*llu: %*llu..%*llu: %6llu: %s\n";
  62 const char *hex_fmt = "%4d: %*llx..%*llx: %*llx..%*llx: %6llx: %s\n";
  63
  64 #define FILEFRAG_FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR)
  65
  66 #define FIBMAP          _IO(0x00, 1)    /* bmap access */
  67 #define FIGETBSZ        _IO(0x00, 2)    /* get the block size used for bmap */
  68
  69 #define LUSTRE_SUPER_MAGIC 0x0BD00BD0
  70
  71 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
  72 #define EXT3_IOC_GETFLAGS               _IOR('f', 1, long)
  73
  74 static int int_log2(int arg)
  75 {
  76         int     l = 0;
  77
  78         arg >>= 1;
  79         while (arg) {
  80                 l++;
  81                 arg >>= 1;
  82         }
  83         return l;
  84 }
  85
  86 static int int_log10(unsigned long long arg)
  87 {
  88         int     l = 0;
  89
  90         arg = arg / 10;
  91         while (arg) {
  92                 l++;
  93                 arg = arg / 10;
  94         }
  95         return l;
  96 }
  97
  98 static unsigned int div_ceil(unsigned int a, unsigned int b)
  99 {
 100         if (!a)
 101                 return 0;
 102         return ((a - 1) / b) + 1;
 103 }
 104
 105 static int get_bmap(int fd, unsigned long block, unsigned long *phy_blk)
 106 {
 107         int     ret;
 108         unsigned int b;
 109
 110         b = block;
 111         ret = ioctl(fd, FIBMAP, &b); /* FIBMAP takes pointer to integer */
 112         if (ret < 0)
 113                 return -errno;
 114         *phy_blk = b;
 115
 116         return ret;
 117 }
 118
 119 static void print_extent_header(void)
 120 {
 121         printf(" ext: %*s %*s length: %*s flags:\n",
 122                logical_width * 2 + 3,
 123                "logical_offset:",
 124                physical_width * 2 + 3, "physical_offset:",
 125                physical_width + 1,
 126                "expected:");
 127 }
 128
 129 static void print_flag(__u32 *flags, __u32 mask, char *buf, const char *name)
 130 {
 131         if ((*flags & mask) == 0)
 132                 return;
 133
 134         strcat(buf, name);
 135         *flags &= ~mask;
 136 }
 137
 138 static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
 139                               unsigned long long expected, int blk_shift,
 140                               ext2fs_struct_stat *st)
 141 {
 142         unsigned long long physical_blk;
 143         unsigned long long logical_blk;
 144         unsigned long long ext_len;
 145         unsigned long long ext_blks;
 146         __u32 fe_flags, mask;
 147         char flags[256] = "";
 148
 149         /* For inline data all offsets should be in bytes, not blocks */
 150         if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
 151                 blk_shift = 0;
 152
 153         ext_len = fm_extent->fe_length >> blk_shift;
 154         ext_blks = (fm_extent->fe_length - 1) >> blk_shift;
 155         logical_blk = fm_extent->fe_logical >> blk_shift;
 156         if (fm_extent->fe_flags & FIEMAP_EXTENT_UNKNOWN) {
 157                 physical_blk = 0;
 158         } else {
 159                 physical_blk = fm_extent->fe_physical >> blk_shift;
 160         }
 161
 162         if (expected)
 163                 sprintf(flags, ext_fmt == hex_fmt ? "%*llx: " : "%*llu: ",
 164                         physical_width, expected >> blk_shift);
 165         else
 166                 sprintf(flags, "%.*s  ", physical_width, "                   ");
 167
 168         fe_flags = fm_extent->fe_flags;
 169         print_flag(&fe_flags, FIEMAP_EXTENT_LAST, flags, "last,");
 170         print_flag(&fe_flags, FIEMAP_EXTENT_UNKNOWN, flags, "unknown_loc,");
 171         print_flag(&fe_flags, FIEMAP_EXTENT_DELALLOC, flags, "delalloc,");
 172         print_flag(&fe_flags, FIEMAP_EXTENT_ENCODED, flags, "encoded,");
 173         print_flag(&fe_flags, FIEMAP_EXTENT_DATA_ENCRYPTED, flags,"encrypted,");
 174         print_flag(&fe_flags, FIEMAP_EXTENT_NOT_ALIGNED, flags, "not_aligned,");
 175         print_flag(&fe_flags, FIEMAP_EXTENT_DATA_INLINE, flags, "inline,");
 176         print_flag(&fe_flags, FIEMAP_EXTENT_DATA_TAIL, flags, "tail_packed,");
 177         print_flag(&fe_flags, FIEMAP_EXTENT_UNWRITTEN, flags, "unwritten,");
 178         print_flag(&fe_flags, FIEMAP_EXTENT_MERGED, flags, "merged,");
 179         print_flag(&fe_flags, FIEMAP_EXTENT_SHARED, flags, "shared,");
 180         /* print any unknown flags as hex values */
 181         for (mask = 1; fe_flags != 0 && mask != 0; mask <<= 1) {
 182                 char hex[sizeof(mask) * 2 + 4]; /* 2 chars/byte + 0x, + NUL */
 183
 184                 if ((fe_flags & mask) == 0)
 185                         continue;
 186                 sprintf(hex, "%#04x,", mask);
 187                 print_flag(&fe_flags, mask, flags, hex);
 188         }
 189
 190         if (fm_extent->fe_logical + fm_extent->fe_length >=
 191             (unsigned long long) st->st_size)
 192                 strcat(flags, "eof,");
 193
 194         /* Remove trailing comma, if any */
 195         if (flags[0] != '\0')
 196                 flags[strnlen(flags, sizeof(flags)) - 1] = '\0';
 197
 198         printf(ext_fmt, cur_ex, logical_width, logical_blk,
 199                logical_width, logical_blk + ext_blks,
 200                physical_width, physical_blk,
 201                physical_width, physical_blk + ext_blks,
 202                ext_len, flags);
 203 }
 204
 205 static int filefrag_fiemap(int fd, int blk_shift, int *num_extents,
 206                            ext2fs_struct_stat *st)
 207 {
 208         __u64 buf[2048];        /* __u64 for proper field alignment */
 209         struct fiemap *fiemap = (struct fiemap *)buf;
 210         struct fiemap_extent *fm_ext = &fiemap->fm_extents[0];
 211         struct fiemap_extent fm_last = {0};
 212         int count = (sizeof(buf) - sizeof(*fiemap)) /
 213                         sizeof(struct fiemap_extent);
 214         unsigned long long expected = 0;
 215         unsigned long long expected_dense = 0;
 216         unsigned long flags = 0;
 217         unsigned int i;
 218         int fiemap_header_printed = 0;
 219         int tot_extents = 0, n = 0;
 220         int last = 0;
 221         int rc;
 222
 223         memset(fiemap, 0, sizeof(struct fiemap));
 224
 225         if (sync_file)
 226                 flags |= FIEMAP_FLAG_SYNC;
 227
 228         if (xattr_map)
 229                 flags |= FIEMAP_FLAG_XATTR;
 230
 231         do {
 232                 fiemap->fm_length = ~0ULL;
 233                 fiemap->fm_flags = flags;
 234                 fiemap->fm_extent_count = count;
 235                 rc = ioctl(fd, FS_IOC_FIEMAP, (unsigned long) fiemap);
 236                 if (rc < 0) {
 237                         static int fiemap_incompat_printed;
 238
 239                         rc = -errno;
 240                         if (rc == -EBADR && !fiemap_incompat_printed) {
 241                                 fprintf(stderr, "FIEMAP failed with unknown "
 242                                                 "flags %x\n",
 243                                        fiemap->fm_flags);
 244                                 fiemap_incompat_printed = 1;
 245                         }
 246                         return rc;
 247                 }
 248
 249                 /* If 0 extents are returned, then more ioctls are not needed */
 250                 if (fiemap->fm_mapped_extents == 0)
 251                         break;
 252
 253                 if (verbose && !fiemap_header_printed) {
 254                         print_extent_header();
 255                         fiemap_header_printed = 1;
 256                 }
 257
 258                 for (i = 0; i < fiemap->fm_mapped_extents; i++) {
 259                         expected_dense = fm_last.fe_physical +
 260                                          fm_last.fe_length;
 261                         expected = fm_last.fe_physical +
 262                                    fm_ext[i].fe_logical - fm_last.fe_logical;
 263                         if (fm_ext[i].fe_logical != 0 &&
 264                             fm_ext[i].fe_physical != expected &&
 265                             fm_ext[i].fe_physical != expected_dense) {
 266                                 tot_extents++;
 267                         } else {
 268                                 expected = 0;
 269                                 if (!tot_extents)
 270                                         tot_extents = 1;
 271                         }
 272                         if (verbose)
 273                                 print_extent_info(&fm_ext[i], n, expected,
 274                                                   blk_shift, st);
 275                         if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
 276                                 last = 1;
 277                         fm_last = fm_ext[i];
 278                         n++;
 279                 }
 280
 281                 fiemap->fm_start = (fm_ext[i - 1].fe_logical +
 282                                     fm_ext[i - 1].fe_length);
 283         } while (last == 0);
 284
 285         *num_extents = tot_extents;
 286
 287         return 0;
 288 }
 289
 290 #define EXT2_DIRECT     12
 291
 292 static int filefrag_fibmap(int fd, int blk_shift, int *num_extents,
 293                            ext2fs_struct_stat *st,
 294                            unsigned long numblocks, int is_ext2)
 295 {
 296         struct fiemap_extent    fm_ext, fm_last;
 297         unsigned long           i, last_block;
 298         unsigned long long      logical, expected = 0;
 299                                 /* Blocks per indirect block */
 300         const long              bpib = st->st_blksize / 4;
 301         int                     count;
 302
 303         memset(&fm_ext, 0, sizeof(fm_ext));
 304         memset(&fm_last, 0, sizeof(fm_last));
 305         if (force_extent) {
 306                 fm_ext.fe_flags = FIEMAP_EXTENT_MERGED;
 307         }
 308
 309         if (sync_file && fsync(fd) != 0)
 310                 return -errno;
 311
 312         for (i = 0, logical = 0, *num_extents = 0, count = last_block = 0;
 313              i < numblocks;
 314              i++, logical += st->st_blksize) {
 315                 unsigned long block = 0;
 316                 int rc;
 317
 318                 if (is_ext2 && last_block) {
 319                         if (((i - EXT2_DIRECT) % bpib) == 0)
 320                                 last_block++;
 321                         if (((i - EXT2_DIRECT - bpib) % (bpib * bpib)) == 0)
 322                                 last_block++;
 323                         if (((i - EXT2_DIRECT - bpib - bpib * bpib) %
 324                              (((unsigned long long)bpib) * bpib * bpib)) == 0)
 325                                 last_block++;
 326                 }
 327                 rc = get_bmap(fd, i, &block);
 328                 if (rc < 0)
 329                         return rc;
 330                 if (block == 0)
 331                         continue;
 332
 333                 if (*num_extents == 0 || block != last_block + 1 ||
 334                     fm_ext.fe_logical + fm_ext.fe_length != logical) {
 335                         /*
 336                          * This is the start of a new extent; figure out where
 337                          * we expected it to be and report the extent.
 338                          */
 339                         if (*num_extents != 0 && fm_last.fe_length) {
 340                                 expected = fm_last.fe_physical +
 341                                         (fm_ext.fe_logical - fm_last.fe_logical);
 342                                 if (expected == fm_ext.fe_physical)
 343                                         expected = 0;
 344                         }
 345                         if (force_extent && *num_extents == 0)
 346                                 print_extent_header();
 347                         if (force_extent && *num_extents != 0) {
 348                                 print_extent_info(&fm_ext, *num_extents - 1,
 349                                                   expected, blk_shift, st);
 350                         }
 351                         if (verbose && expected != 0) {
 352                                 printf("Discontinuity: Block %llu is at %llu "
 353                                        "(was %llu)\n",
 354                                         fm_ext.fe_logical / st->st_blksize,
 355                                         fm_ext.fe_physical / st->st_blksize,
 356                                         expected / st->st_blksize);
 357                         }
 358                         /* create the new extent */
 359                         fm_last = fm_ext;
 360                         (*num_extents)++;
 361                         fm_ext.fe_physical = block * st->st_blksize;
 362                         fm_ext.fe_logical = logical;
 363                         fm_ext.fe_length = 0;
 364                 }
 365                 fm_ext.fe_length += st->st_blksize;
 366                 last_block = block;
 367         }
 368         if (force_extent && *num_extents != 0) {
 369                 if (fm_last.fe_length) {
 370                         expected = fm_last.fe_physical +
 371                                    (fm_ext.fe_logical - fm_last.fe_logical);
 372                         if (expected == fm_ext.fe_physical)
 373                                 expected = 0;
 374                 }
 375                 print_extent_info(&fm_ext, *num_extents - 1, expected,
 376                                   blk_shift, st);
 377         }
 378
 379         return count;
 380 }
 381
 382 static int frag_report(const char *filename)
 383 {
 384         static struct statfs fsinfo;
 385         static unsigned int blksize;
 386         ext2fs_struct_stat st;
 387         int             blk_shift;
 388         long            fd;
 389         unsigned long long      numblocks;
 390         int             data_blocks_per_cyl = 1;
 391         int             num_extents = 1, expected = ~0;
 392         int             is_ext2 = 0;
 393         static dev_t    last_device;
 394         int             width;
 395         int             rc = 0;
 396
 397 #if defined(HAVE_OPEN64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 398         fd = open64(filename, O_RDONLY);
 399 #else
 400         fd = open(filename, O_RDONLY);
 401 #endif
 402         if (fd < 0) {
 403                 rc = -errno;
 404                 perror("open");
 405                 return rc;
 406         }
 407
 408 #if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 409         if (fstat64(fd, &st) < 0) {
 410 #else
 411         if (fstat(fd, &st) < 0) {
 412 #endif
 413                 rc = -errno;
 414                 perror("stat");
 415                 goto out_close;
 416         }
 417
 418         if (last_device != st.st_dev) {
 419                 if (fstatfs(fd, &fsinfo) < 0) {
 420                         rc = -errno;
 421                         perror("fstatfs");
 422                         goto out_close;
 423                 }
 424                 if (ioctl(fd, FIGETBSZ, &blksize) < 0)
 425                         blksize = fsinfo.f_bsize;
 426                 if (verbose)
 427                         printf("Filesystem type is: %lx\n",
 428                                (unsigned long)fsinfo.f_type);
 429         }
 430         st.st_blksize = blksize;
 431         if (fsinfo.f_type == 0xef51 || fsinfo.f_type == 0xef52 ||
 432             fsinfo.f_type == 0xef53) {
 433                 unsigned int    flags;
 434
 435                 if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) == 0 &&
 436                     !(flags & EXT4_EXTENTS_FL))
 437                         is_ext2 = 1;
 438         }
 439
 440         if (is_ext2) {
 441                 long cylgroups = div_ceil(fsinfo.f_blocks, blksize * 8);
 442
 443                 if (verbose && last_device != st.st_dev)
 444                         printf("Filesystem cylinder groups approximately %ld\n",
 445                                cylgroups);
 446
 447                 data_blocks_per_cyl = blksize * 8 -
 448                                         (fsinfo.f_files / 8 / cylgroups) - 3;
 449         }
 450         last_device = st.st_dev;
 451
 452         width = int_log10(fsinfo.f_blocks);
 453         if (width > physical_width)
 454                 physical_width = width;
 455
 456         numblocks = (st.st_size + blksize - 1) / blksize;
 457         if (blocksize != 0)
 458                 blk_shift = int_log2(blocksize);
 459         else
 460                 blk_shift = int_log2(blksize);
 461
 462         width = int_log10(numblocks);
 463         if (width > logical_width)
 464                 logical_width = width;
 465         if (verbose)
 466                 printf("File size of %s is %llu (%llu block%s of %d bytes)\n",
 467                        filename, (unsigned long long)st.st_size,
 468                        numblocks * blksize >> blk_shift,
 469                        numblocks == 1 ? "" : "s", 1 << blk_shift);
 470
 471         if (!force_bmap) {
 472                 rc = filefrag_fiemap(fd, blk_shift, &num_extents, &st);
 473                 expected = 0;
 474         }
 475
 476         if (force_bmap || rc < 0) { /* FIEMAP failed, try FIBMAP instead */
 477                 expected = filefrag_fibmap(fd, blk_shift, &num_extents,
 478                                            &st, numblocks, is_ext2);
 479                 if (expected < 0) {
 480                         if (expected == -EINVAL || expected == -ENOTTY) {
 481                                 fprintf(stderr, "%s: FIBMAP unsupported\n",
 482                                         filename);
 483                         } else if (expected == -EPERM) {
 484                                 fprintf(stderr,
 485                                         "%s: FIBMAP requires root privileges\n",
 486                                         filename);
 487                         } else {
 488                                 fprintf(stderr, "%s: FIBMAP error: %s",
 489                                         filename, strerror(expected));
 490                         }
 491                         rc = expected;
 492                         goto out_close;
 493                 } else {
 494                         rc = 0;
 495                 }
 496                 expected = expected / data_blocks_per_cyl + 1;
 497         }
 498
 499         if (num_extents == 1)
 500                 printf("%s: 1 extent found", filename);
 501         else
 502                 printf("%s: %d extents found", filename, num_extents);
 503         /* count, and thus expected, only set for indirect FIBMAP'd files */
 504         if (is_ext2 && expected && expected < num_extents)
 505                 printf(", perfection would be %d extent%s\n", expected,
 506                         (expected > 1) ? "s" : "");
 507         else
 508                 fputc('\n', stdout);
 509 out_close:
 510         close(fd);
 511
 512         return rc;
 513 }
 514
 515 static void usage(const char *progname)
 516 {
 517         fprintf(stderr, "Usage: %s [-b{blocksize}] [-BeksvxX] file ...\n",
 518                 progname);
 519         exit(1);
 520 }
 521
 522 int main(int argc, char**argv)
 523 {
 524         char **cpp;
 525         int rc = 0, c;
 526
 527         while ((c = getopt(argc, argv, "Bb::eksvxX")) != EOF) {
 528                 switch (c) {
 529                 case 'B':
 530                         force_bmap++;
 531                         break;
 532                 case 'b':
 533                         if (optarg) {
 534                                 char *end;
 535                                 blocksize = strtoul(optarg, &end, 0);
 536                                 if (end) {
 537                                         switch (end[0]) {
 538                                         case 'g':
 539                                         case 'G':
 540                                                 blocksize *= 1024;
 541                                                 /* no break */
 542                                         case 'm':
 543                                         case 'M':
 544                                                 blocksize *= 1024;
 545                                                 /* no break */
 546                                         case 'k':
 547                                         case 'K':
 548                                                 blocksize *= 1024;
 549                                                 break;
 550                                         default:
 551                                                 break;
 552                                         }
 553                                 }
 554                         } else { /* Allow -b without argument for compat. Remove
 555                                   * this eventually so "-b {blocksize}" works */
 556                                 fprintf(stderr, "%s: -b needs a blocksize "
 557                                         "option, assuming 1024-byte blocks.\n",
 558                                         argv[0]);
 559                                 blocksize = 1024;
 560                         }
 561                         break;
 562                 case 'e':
 563                         force_extent++;
 564                         if (!verbose)
 565                                 verbose++;
 566                         break;
 567                 case 'k':
 568                         blocksize = 1024;
 569                         break;
 570                 case 's':
 571                         sync_file++;
 572                         break;
 573                 case 'v':
 574                         verbose++;
 575                         break;
 576                 case 'x':
 577                         xattr_map++;
 578                         break;
 579                 case 'X':
 580                         ext_fmt = hex_fmt;
 581                         break;
 582                 default:
 583                         usage(argv[0]);
 584                         break;
 585                 }
 586         }
 587
 588         if (optind == argc)
 589                 usage(argv[0]);
 590
 591         for (cpp = argv + optind; *cpp != NULL; cpp++) {
 592                 int rc2 = frag_report(*cpp);
 593
 594                 if (rc2 < 0 && rc == 0)
 595                         rc = rc2;
 596         }
 597
 598         return -rc;
 599 }
 600 #endif