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 #ifdef HAVE_LINUX_FD_H
  49 #include <linux/fd.h>
  50 #endif
  51 #include <ext2fs/ext2fs.h>
  52 #include <ext2fs/ext2_types.h>
  53 #include <ext2fs/fiemap.h>
  54
  55 int verbose = 0;
  56 int blocksize;          /* Use specified blocksize (default 1kB) */
  57 int sync_file = 0;      /* fsync file before getting the mapping */
  58 int xattr_map = 0;      /* get xattr mapping */
  59 int force_bmap; /* force use of FIBMAP instead of FIEMAP */
  60 int force_extent;       /* print output in extent format always */
  61 int logical_width = 8;
  62 int physical_width = 10;
  63 const char *ext_fmt = "%4d: %*llu..%*llu: %*llu..%*llu: %6llu: %s\n";
  64 const char *hex_fmt = "%4d: %*llx..%*llx: %*llx..%*llx: %6llx: %s\n";
  65
  66 #define FILEFRAG_FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR)
  67
  68 #define FIBMAP          _IO(0x00, 1)    /* bmap access */
  69 #define FIGETBSZ        _IO(0x00, 2)    /* get the block size used for bmap */
  70
  71 #define LUSTRE_SUPER_MAGIC 0x0BD00BD0
  72
  73 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
  74 #define EXT3_IOC_GETFLAGS               _IOR('f', 1, long)
  75
  76 static int int_log2(int arg)
  77 {
  78         int     l = 0;
  79
  80         arg >>= 1;
  81         while (arg) {
  82                 l++;
  83                 arg >>= 1;
  84         }
  85         return l;
  86 }
  87
  88 static int int_log10(unsigned long long arg)
  89 {
  90         int     l = 0;
  91
  92         arg = arg / 10;
  93         while (arg) {
  94                 l++;
  95                 arg = arg / 10;
  96         }
  97         return l;
  98 }
  99
 100 static unsigned int div_ceil(unsigned int a, unsigned int b)
 101 {
 102         if (!a)
 103                 return 0;
 104         return ((a - 1) / b) + 1;
 105 }
 106
 107 static int get_bmap(int fd, unsigned long block, unsigned long *phy_blk)
 108 {
 109         int     ret;
 110         unsigned int b;
 111
 112         b = block;
 113         ret = ioctl(fd, FIBMAP, &b); /* FIBMAP takes pointer to integer */
 114         if (ret < 0)
 115                 return -errno;
 116         *phy_blk = b;
 117
 118         return ret;
 119 }
 120
 121 static void print_extent_header(void)
 122 {
 123         printf(" ext: %*s %*s length: %*s flags:\n",
 124                logical_width * 2 + 3,
 125                "logical_offset:",
 126                physical_width * 2 + 3, "physical_offset:",
 127                physical_width + 1,
 128                "expected:");
 129 }
 130
 131 static void print_flag(__u32 *flags, __u32 mask, char *buf, const char *name)
 132 {
 133         if ((*flags & mask) == 0)
 134                 return;
 135
 136         strcat(buf, name);
 137         *flags &= ~mask;
 138 }
 139
 140 static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
 141                               unsigned long long expected, int blk_shift,
 142                               ext2fs_struct_stat *st)
 143 {
 144         unsigned long long physical_blk;
 145         unsigned long long logical_blk;
 146         unsigned long long ext_len;
 147         unsigned long long ext_blks;
 148         __u32 fe_flags, mask;
 149         char flags[256] = "";
 150
 151         /* For inline data all offsets should be in bytes, not blocks */
 152         if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
 153                 blk_shift = 0;
 154
 155         ext_len = fm_extent->fe_length >> blk_shift;
 156         ext_blks = (fm_extent->fe_length - 1) >> blk_shift;
 157         logical_blk = fm_extent->fe_logical >> blk_shift;
 158         if (fm_extent->fe_flags & FIEMAP_EXTENT_UNKNOWN) {
 159                 physical_blk = 0;
 160         } else {
 161                 physical_blk = fm_extent->fe_physical >> blk_shift;
 162         }
 163
 164         if (expected)
 165                 sprintf(flags, ext_fmt == hex_fmt ? "%*llx: " : "%*llu: ",
 166                         physical_width, expected >> blk_shift);
 167         else
 168                 sprintf(flags, "%.*s  ", physical_width, "                   ");
 169
 170         fe_flags = fm_extent->fe_flags;
 171         print_flag(&fe_flags, FIEMAP_EXTENT_LAST, flags, "last,");
 172         print_flag(&fe_flags, FIEMAP_EXTENT_UNKNOWN, flags, "unknown_loc,");
 173         print_flag(&fe_flags, FIEMAP_EXTENT_DELALLOC, flags, "delalloc,");
 174         print_flag(&fe_flags, FIEMAP_EXTENT_ENCODED, flags, "encoded,");
 175         print_flag(&fe_flags, FIEMAP_EXTENT_DATA_ENCRYPTED, flags,"encrypted,");
 176         print_flag(&fe_flags, FIEMAP_EXTENT_NOT_ALIGNED, flags, "not_aligned,");
 177         print_flag(&fe_flags, FIEMAP_EXTENT_DATA_INLINE, flags, "inline,");
 178         print_flag(&fe_flags, FIEMAP_EXTENT_DATA_TAIL, flags, "tail_packed,");
 179         print_flag(&fe_flags, FIEMAP_EXTENT_UNWRITTEN, flags, "unwritten,");
 180         print_flag(&fe_flags, FIEMAP_EXTENT_MERGED, flags, "merged,");
 181         print_flag(&fe_flags, FIEMAP_EXTENT_SHARED, flags, "shared,");
 182         /* print any unknown flags as hex values */
 183         for (mask = 1; fe_flags != 0 && mask != 0; mask <<= 1) {
 184                 char hex[sizeof(mask) * 2 + 4]; /* 2 chars/byte + 0x, + NUL */
 185
 186                 if ((fe_flags & mask) == 0)
 187                         continue;
 188                 sprintf(hex, "%#04x,", mask);
 189                 print_flag(&fe_flags, mask, flags, hex);
 190         }
 191
 192         if (fm_extent->fe_logical + fm_extent->fe_length >=
 193             (unsigned long long) st->st_size)
 194                 strcat(flags, "eof,");
 195
 196         /* Remove trailing comma, if any */
 197         if (flags[0] != '\0')
 198                 flags[strnlen(flags, sizeof(flags)) - 1] = '\0';
 199
 200         printf(ext_fmt, cur_ex, logical_width, logical_blk,
 201                logical_width, logical_blk + ext_blks,
 202                physical_width, physical_blk,
 203                physical_width, physical_blk + ext_blks,
 204                ext_len, flags);
 205 }
 206
 207 static int filefrag_fiemap(int fd, int blk_shift, int *num_extents,
 208                            ext2fs_struct_stat *st)
 209 {
 210         __u64 buf[2048];        /* __u64 for proper field alignment */
 211         struct fiemap *fiemap = (struct fiemap *)buf;
 212         struct fiemap_extent *fm_ext = &fiemap->fm_extents[0];
 213         struct fiemap_extent fm_last;
 214         int count = (sizeof(buf) - sizeof(*fiemap)) /
 215                         sizeof(struct fiemap_extent);
 216         unsigned long long expected = 0;
 217         unsigned long long expected_dense = 0;
 218         unsigned long flags = 0;
 219         unsigned int i;
 220         int fiemap_header_printed = 0;
 221         int tot_extents = 0, n = 0;
 222         int last = 0;
 223         int rc;
 224
 225         memset(fiemap, 0, sizeof(struct fiemap));
 226         memset(&fm_last, 0, sizeof(fm_last));
 227
 228         if (sync_file)
 229                 flags |= FIEMAP_FLAG_SYNC;
 230
 231         if (xattr_map)
 232                 flags |= FIEMAP_FLAG_XATTR;
 233
 234         do {
 235                 fiemap->fm_length = ~0ULL;
 236                 fiemap->fm_flags = flags;
 237                 fiemap->fm_extent_count = count;
 238                 rc = ioctl(fd, FS_IOC_FIEMAP, (unsigned long) fiemap);
 239                 if (rc < 0) {
 240                         static int fiemap_incompat_printed;
 241
 242                         rc = -errno;
 243                         if (rc == -EBADR && !fiemap_incompat_printed) {
 244                                 fprintf(stderr, "FIEMAP failed with unknown "
 245                                                 "flags %x\n",
 246                                        fiemap->fm_flags);
 247                                 fiemap_incompat_printed = 1;
 248                         }
 249                         return rc;
 250                 }
 251
 252                 /* If 0 extents are returned, then more ioctls are not needed */
 253                 if (fiemap->fm_mapped_extents == 0)
 254                         break;
 255
 256                 if (verbose && !fiemap_header_printed) {
 257                         print_extent_header();
 258                         fiemap_header_printed = 1;
 259                 }
 260
 261                 for (i = 0; i < fiemap->fm_mapped_extents; i++) {
 262                         expected_dense = fm_last.fe_physical +
 263                                          fm_last.fe_length;
 264                         expected = fm_last.fe_physical +
 265                                    fm_ext[i].fe_logical - fm_last.fe_logical;
 266                         if (fm_ext[i].fe_logical != 0 &&
 267                             fm_ext[i].fe_physical != expected &&
 268                             fm_ext[i].fe_physical != expected_dense) {
 269                                 tot_extents++;
 270                         } else {
 271                                 expected = 0;
 272                                 if (!tot_extents)
 273                                         tot_extents = 1;
 274                         }
 275                         if (verbose)
 276                                 print_extent_info(&fm_ext[i], n, expected,
 277                                                   blk_shift, st);
 278                         if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
 279                                 last = 1;
 280                         fm_last = fm_ext[i];
 281                         n++;
 282                 }
 283
 284                 fiemap->fm_start = (fm_ext[i - 1].fe_logical +
 285                                     fm_ext[i - 1].fe_length);
 286         } while (last == 0);
 287
 288         *num_extents = tot_extents;
 289
 290         return 0;
 291 }
 292
 293 #define EXT2_DIRECT     12
 294
 295 static int filefrag_fibmap(int fd, int blk_shift, int *num_extents,
 296                            ext2fs_struct_stat *st,
 297                            unsigned long numblocks, int is_ext2)
 298 {
 299         struct fiemap_extent    fm_ext, fm_last;
 300         unsigned long           i, last_block;
 301         unsigned long long      logical, expected = 0;
 302                                 /* Blocks per indirect block */
 303         const long              bpib = st->st_blksize / 4;
 304         int                     count;
 305
 306         memset(&fm_ext, 0, sizeof(fm_ext));
 307         memset(&fm_last, 0, sizeof(fm_last));
 308         if (force_extent) {
 309                 fm_ext.fe_flags = FIEMAP_EXTENT_MERGED;
 310         }
 311
 312         if (sync_file && fsync(fd) != 0)
 313                 return -errno;
 314
 315         for (i = 0, logical = 0, *num_extents = 0, count = last_block = 0;
 316              i < numblocks;
 317              i++, logical += st->st_blksize) {
 318                 unsigned long block = 0;
 319                 int rc;
 320
 321                 if (is_ext2 && last_block) {
 322                         if (((i - EXT2_DIRECT) % bpib) == 0)
 323                                 last_block++;
 324                         if (((i - EXT2_DIRECT - bpib) % (bpib * bpib)) == 0)
 325                                 last_block++;
 326                         if (((i - EXT2_DIRECT - bpib - bpib * bpib) %
 327                              (((unsigned long long)bpib) * bpib * bpib)) == 0)
 328                                 last_block++;
 329                 }
 330                 rc = get_bmap(fd, i, &block);
 331                 if (rc < 0)
 332                         return rc;
 333                 if (block == 0)
 334                         continue;
 335
 336                 if (*num_extents == 0 || block != last_block + 1 ||
 337                     fm_ext.fe_logical + fm_ext.fe_length != logical) {
 338                         /*
 339                          * This is the start of a new extent; figure out where
 340                          * we expected it to be and report the extent.
 341                          */
 342                         if (*num_extents != 0 && fm_last.fe_length) {
 343                                 expected = fm_last.fe_physical +
 344                                         (fm_ext.fe_logical - fm_last.fe_logical);
 345                                 if (expected == fm_ext.fe_physical)
 346                                         expected = 0;
 347                         }
 348                         if (force_extent && *num_extents == 0)
 349                                 print_extent_header();
 350                         if (force_extent && *num_extents != 0) {
 351                                 print_extent_info(&fm_ext, *num_extents - 1,
 352                                                   expected, blk_shift, st);
 353                         }
 354                         if (verbose && expected != 0) {
 355                                 printf("Discontinuity: Block %llu is at %llu "
 356                                        "(was %llu)\n",
 357                                         fm_ext.fe_logical / st->st_blksize,
 358                                         fm_ext.fe_physical / st->st_blksize,
 359                                         expected / st->st_blksize);
 360                         }
 361                         /* create the new extent */
 362                         fm_last = fm_ext;
 363                         (*num_extents)++;
 364                         fm_ext.fe_physical = block * st->st_blksize;
 365                         fm_ext.fe_logical = logical;
 366                         fm_ext.fe_length = 0;
 367                 }
 368                 fm_ext.fe_length += st->st_blksize;
 369                 last_block = block;
 370         }
 371         if (force_extent && *num_extents != 0) {
 372                 if (fm_last.fe_length) {
 373                         expected = fm_last.fe_physical +
 374                                    (fm_ext.fe_logical - fm_last.fe_logical);
 375                         if (expected == fm_ext.fe_physical)
 376                                 expected = 0;
 377                 }
 378                 print_extent_info(&fm_ext, *num_extents - 1, expected,
 379                                   blk_shift, st);
 380         }
 381
 382         return count;
 383 }
 384
 385 static int frag_report(const char *filename)
 386 {
 387         static struct statfs fsinfo;
 388         static unsigned int blksize;
 389         ext2fs_struct_stat st;
 390         int             blk_shift;
 391         long            fd;
 392         unsigned long long      numblocks;
 393         int             data_blocks_per_cyl = 1;
 394         int             num_extents = 1, expected = ~0;
 395         int             is_ext2 = 0;
 396         static dev_t    last_device;
 397         int             width;
 398         int             rc = 0;
 399
 400 #if defined(HAVE_OPEN64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 401         fd = open64(filename, O_RDONLY);
 402 #else
 403         fd = open(filename, O_RDONLY);
 404 #endif
 405         if (fd < 0) {
 406                 rc = -errno;
 407                 perror("open");
 408                 return rc;
 409         }
 410
 411 #if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 412         if (fstat64(fd, &st) < 0) {
 413 #else
 414         if (fstat(fd, &st) < 0) {
 415 #endif
 416                 rc = -errno;
 417                 perror("stat");
 418                 goto out_close;
 419         }
 420
 421         if (last_device != st.st_dev) {
 422                 if (fstatfs(fd, &fsinfo) < 0) {
 423                         rc = -errno;
 424                         perror("fstatfs");
 425                         goto out_close;
 426                 }
 427                 if (ioctl(fd, FIGETBSZ, &blksize) < 0)
 428                         blksize = fsinfo.f_bsize;
 429                 if (verbose)
 430                         printf("Filesystem type is: %lx\n",
 431                                (unsigned long)fsinfo.f_type);
 432         }
 433         st.st_blksize = blksize;
 434         if (fsinfo.f_type == 0xef51 || fsinfo.f_type == 0xef52 ||
 435             fsinfo.f_type == 0xef53) {
 436                 unsigned int    flags;
 437
 438                 if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) == 0 &&
 439                     !(flags & EXT4_EXTENTS_FL))
 440                         is_ext2 = 1;
 441         }
 442
 443         if (is_ext2) {
 444                 long cylgroups = div_ceil(fsinfo.f_blocks, blksize * 8);
 445
 446                 if (verbose && last_device != st.st_dev)
 447                         printf("Filesystem cylinder groups approximately %ld\n",
 448                                cylgroups);
 449
 450                 data_blocks_per_cyl = blksize * 8 -
 451                                         (fsinfo.f_files / 8 / cylgroups) - 3;
 452         }
 453         last_device = st.st_dev;
 454
 455         width = int_log10(fsinfo.f_blocks);
 456         if (width > physical_width)
 457                 physical_width = width;
 458
 459         numblocks = (st.st_size + blksize - 1) / blksize;
 460         if (blocksize != 0)
 461                 blk_shift = int_log2(blocksize);
 462         else
 463                 blk_shift = int_log2(blksize);
 464
 465         width = int_log10(numblocks);
 466         if (width > logical_width)
 467                 logical_width = width;
 468         if (verbose)
 469                 printf("File size of %s is %llu (%llu block%s of %d bytes)\n",
 470                        filename, (unsigned long long)st.st_size,
 471                        numblocks * blksize >> blk_shift,
 472                        numblocks == 1 ? "" : "s", 1 << blk_shift);
 473
 474         if (!force_bmap) {
 475                 rc = filefrag_fiemap(fd, blk_shift, &num_extents, &st);
 476                 expected = 0;
 477         }
 478
 479         if (force_bmap || rc < 0) { /* FIEMAP failed, try FIBMAP instead */
 480                 expected = filefrag_fibmap(fd, blk_shift, &num_extents,
 481                                            &st, numblocks, is_ext2);
 482                 if (expected < 0) {
 483                         if (expected == -EINVAL || expected == -ENOTTY) {
 484                                 fprintf(stderr, "%s: FIBMAP unsupported\n",
 485                                         filename);
 486                         } else if (expected == -EPERM) {
 487                                 fprintf(stderr,
 488                                         "%s: FIBMAP requires root privileges\n",
 489                                         filename);
 490                         } else {
 491                                 fprintf(stderr, "%s: FIBMAP error: %s",
 492                                         filename, strerror(expected));
 493                         }
 494                         rc = expected;
 495                         goto out_close;
 496                 } else {
 497                         rc = 0;
 498                 }
 499                 expected = expected / data_blocks_per_cyl + 1;
 500         }
 501
 502         if (num_extents == 1)
 503                 printf("%s: 1 extent found", filename);
 504         else
 505                 printf("%s: %d extents found", filename, num_extents);
 506         /* count, and thus expected, only set for indirect FIBMAP'd files */
 507         if (is_ext2 && expected && expected < num_extents)
 508                 printf(", perfection would be %d extent%s\n", expected,
 509                         (expected > 1) ? "s" : "");
 510         else
 511                 fputc('\n', stdout);
 512 out_close:
 513         close(fd);
 514
 515         return rc;
 516 }
 517
 518 static void usage(const char *progname)
 519 {
 520         fprintf(stderr, "Usage: %s [-b{blocksize}] [-BeksvxX] file ...\n",
 521                 progname);
 522         exit(1);
 523 }
 524
 525 int main(int argc, char**argv)
 526 {
 527         char **cpp;
 528         int rc = 0, c;
 529
 530         while ((c = getopt(argc, argv, "Bb::eksvxX")) != EOF) {
 531                 switch (c) {
 532                 case 'B':
 533                         force_bmap++;
 534                         break;
 535                 case 'b':
 536                         if (optarg) {
 537                                 char *end;
 538                                 blocksize = strtoul(optarg, &end, 0);
 539                                 if (end) {
 540 #if __GNUC_PREREQ (7, 0)
 541 #pragma GCC diagnostic push
 542 #pragma GCC diagnostic ignored "-Wimplicit-fallthrough"
 543 #endif
 544                                         switch (end[0]) {
 545                                         case 'g':
 546                                         case 'G':
 547                                                 blocksize *= 1024;
 548                                                 /* fall through */
 549                                         case 'm':
 550                                         case 'M':
 551                                                 blocksize *= 1024;
 552                                                 /* fall through */
 553                                         case 'k':
 554                                         case 'K':
 555                                                 blocksize *= 1024;
 556                                                 break;
 557                                         default:
 558                                                 break;
 559                                         }
 560 #if __GNUC_PREREQ (7, 0)
 561 #pragma GCC diagnostic pop
 562 #endif
 563                                 }
 564                         } else { /* Allow -b without argument for compat. Remove
 565                                   * this eventually so "-b {blocksize}" works */
 566                                 fprintf(stderr, "%s: -b needs a blocksize "
 567                                         "option, assuming 1024-byte blocks.\n",
 568                                         argv[0]);
 569                                 blocksize = 1024;
 570                         }
 571                         break;
 572                 case 'e':
 573                         force_extent++;
 574                         if (!verbose)
 575                                 verbose++;
 576                         break;
 577                 case 'k':
 578                         blocksize = 1024;
 579                         break;
 580                 case 's':
 581                         sync_file++;
 582                         break;
 583                 case 'v':
 584                         verbose++;
 585                         break;
 586                 case 'x':
 587                         xattr_map++;
 588                         break;
 589                 case 'X':
 590                         ext_fmt = hex_fmt;
 591                         break;
 592                 default:
 593                         usage(argv[0]);
 594                         break;
 595                 }
 596         }
 597
 598         if (optind == argc)
 599                 usage(argv[0]);
 600
 601         for (cpp = argv + optind; *cpp != NULL; cpp++) {
 602                 int rc2 = frag_report(*cpp);
 603
 604                 if (rc2 < 0 && rc == 0)
 605                         rc = rc2;
 606         }
 607
 608         return -rc;
 609 }
 610 #endif