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[6];
 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         int count = (sizeof(buf) - sizeof(*fiemap)) /
 212                         sizeof(struct fiemap_extent);
 213         unsigned long long expected = 0;
 214         unsigned long flags = 0;
 215         unsigned int i;
 216         int fiemap_header_printed = 0;
 217         int tot_extents = 0, n = 0;
 218         int last = 0;
 219         int rc;
 220
 221         memset(fiemap, 0, sizeof(struct fiemap));
 222
 223         if (sync_file)
 224                 flags |= FIEMAP_FLAG_SYNC;
 225
 226         if (xattr_map)
 227                 flags |= FIEMAP_FLAG_XATTR;
 228
 229         do {
 230                 fiemap->fm_length = ~0ULL;
 231                 fiemap->fm_flags = flags;
 232                 fiemap->fm_extent_count = count;
 233                 rc = ioctl(fd, FS_IOC_FIEMAP, (unsigned long) fiemap);
 234                 if (rc < 0) {
 235                         static int fiemap_incompat_printed;
 236
 237                         rc = -errno;
 238                         if (rc == -EBADR && !fiemap_incompat_printed) {
 239                                 fprintf(stderr, "FIEMAP failed with unknown "
 240                                                 "flags %x\n",
 241                                        fiemap->fm_flags);
 242                                 fiemap_incompat_printed = 1;
 243                         }
 244                         return rc;
 245                 }
 246
 247                 /* If 0 extents are returned, then more ioctls are not needed */
 248                 if (fiemap->fm_mapped_extents == 0)
 249                         break;
 250
 251                 if (verbose && !fiemap_header_printed) {
 252                         print_extent_header();
 253                         fiemap_header_printed = 1;
 254                 }
 255
 256                 for (i = 0; i < fiemap->fm_mapped_extents; i++) {
 257                         if (fm_ext[i].fe_logical != 0 &&
 258                             fm_ext[i].fe_physical != expected) {
 259                                 tot_extents++;
 260                         } else {
 261                                 expected = 0;
 262                                 if (!tot_extents)
 263                                         tot_extents = 1;
 264                         }
 265                         if (verbose)
 266                                 print_extent_info(&fm_ext[i], n, expected,
 267                                                   blk_shift, st);
 268
 269                         expected = fm_ext[i].fe_physical + fm_ext[i].fe_length;
 270                         if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
 271                                 last = 1;
 272                         n++;
 273                 }
 274
 275                 fiemap->fm_start = (fm_ext[i - 1].fe_logical +
 276                                     fm_ext[i - 1].fe_length);
 277         } while (last == 0);
 278
 279         *num_extents = tot_extents;
 280
 281         return 0;
 282 }
 283
 284 #define EXT2_DIRECT     12
 285
 286 static int filefrag_fibmap(int fd, int blk_shift, int *num_extents,
 287                            ext2fs_struct_stat *st,
 288                            unsigned long numblocks, int is_ext2)
 289 {
 290         struct fiemap_extent    fm_ext;
 291         unsigned long           i, last_block;
 292         unsigned long long      logical;
 293                                 /* Blocks per indirect block */
 294         const long              bpib = st->st_blksize / 4;
 295         int                     count;
 296
 297         memset(&fm_ext, 0, sizeof(fm_ext));
 298         if (force_extent) {
 299                 fm_ext.fe_flags = FIEMAP_EXTENT_MERGED;
 300         }
 301
 302         if (sync_file)
 303                 fsync(fd);
 304
 305         for (i = 0, logical = 0, *num_extents = 0, count = last_block = 0;
 306              i < numblocks;
 307              i++, logical += st->st_blksize) {
 308                 unsigned long block = 0;
 309                 int rc;
 310
 311                 if (is_ext2 && last_block) {
 312                         if (((i - EXT2_DIRECT) % bpib) == 0)
 313                                 last_block++;
 314                         if (((i - EXT2_DIRECT - bpib) % (bpib * bpib)) == 0)
 315                                 last_block++;
 316                         if (((i - EXT2_DIRECT - bpib - bpib * bpib) %
 317                              (((unsigned long long)bpib) * bpib * bpib)) == 0)
 318                                 last_block++;
 319                 }
 320                 rc = get_bmap(fd, i, &block);
 321                 if (rc < 0)
 322                         return rc;
 323                 if (block == 0)
 324                         continue;
 325                 if (*num_extents == 0) {
 326                         (*num_extents)++;
 327                         if (force_extent) {
 328                                 print_extent_header();
 329                                 fm_ext.fe_physical = block * st->st_blksize;
 330                         }
 331                 }
 332                 count++;
 333                 if (force_extent && last_block != 0 &&
 334                     (block != last_block + 1 ||
 335                      fm_ext.fe_logical + fm_ext.fe_length != logical)) {
 336                         print_extent_info(&fm_ext, *num_extents - 1,
 337                                           (last_block + 1) * st->st_blksize,
 338                                           blk_shift, st);
 339                         fm_ext.fe_length = 0;
 340                         (*num_extents)++;
 341                         fm_ext.fe_logical = logical;
 342                         fm_ext.fe_physical = block * st->st_blksize;
 343                 } else if (last_block && (block != last_block + 1)) {
 344                         if (verbose)
 345                                 printf("Discontinuity: Block %ld is at %lu (was "
 346                                        "%lu)\n", i, block, last_block + 1);
 347                         fm_ext.fe_length = 0;
 348                         (*num_extents)++;
 349                         fm_ext.fe_logical = logical;
 350                         fm_ext.fe_physical = block * st->st_blksize;
 351                 }
 352                 fm_ext.fe_length += st->st_blksize;
 353                 last_block = block;
 354         }
 355
 356         if (force_extent)
 357                 print_extent_info(&fm_ext, *num_extents - 1,
 358                                   last_block * st->st_blksize, blk_shift, st);
 359
 360         return count;
 361 }
 362
 363 static int frag_report(const char *filename)
 364 {
 365         static struct statfs fsinfo;
 366         static unsigned int blksize;
 367         ext2fs_struct_stat st;
 368         int             blk_shift;
 369         long            fd;
 370         unsigned long long      numblocks;
 371         int             data_blocks_per_cyl = 1;
 372         int             num_extents = 1, expected = ~0;
 373         int             is_ext2 = 0;
 374         static dev_t    last_device;
 375         int             width;
 376         int             rc = 0;
 377
 378 #if defined(HAVE_OPEN64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 379         fd = open64(filename, O_RDONLY);
 380 #else
 381         fd = open(filename, O_RDONLY);
 382 #endif
 383         if (fd < 0) {
 384                 rc = -errno;
 385                 perror("open");
 386                 return rc;
 387         }
 388
 389 #if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 390         if (fstat64(fd, &st) < 0) {
 391 #else
 392         if (fstat(fd, &st) < 0) {
 393 #endif
 394                 rc = -errno;
 395                 perror("stat");
 396                 goto out_close;
 397         }
 398
 399         if (last_device != st.st_dev) {
 400                 if (fstatfs(fd, &fsinfo) < 0) {
 401                         rc = -errno;
 402                         perror("fstatfs");
 403                         goto out_close;
 404                 }
 405                 if (ioctl(fd, FIGETBSZ, &blksize) < 0)
 406                         blksize = fsinfo.f_bsize;
 407                 if (verbose)
 408                         printf("Filesystem type is: %lx\n",
 409                                (unsigned long)fsinfo.f_type);
 410         }
 411         st.st_blksize = blksize;
 412         if (fsinfo.f_type == 0xef51 || fsinfo.f_type == 0xef52 ||
 413             fsinfo.f_type == 0xef53) {
 414                 unsigned int    flags;
 415
 416                 if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) == 0 &&
 417                     !(flags & EXT4_EXTENTS_FL))
 418                         is_ext2 = 1;
 419         }
 420
 421         if (is_ext2) {
 422                 long cylgroups = div_ceil(fsinfo.f_blocks, blksize * 8);
 423
 424                 if (verbose && last_device != st.st_dev)
 425                         printf("Filesystem cylinder groups approximately %ld\n",
 426                                cylgroups);
 427
 428                 data_blocks_per_cyl = blksize * 8 -
 429                                         (fsinfo.f_files / 8 / cylgroups) - 3;
 430         }
 431         last_device = st.st_dev;
 432
 433         width = int_log10(fsinfo.f_blocks);
 434         if (width > physical_width)
 435                 physical_width = width;
 436
 437         numblocks = (st.st_size + blksize - 1) / blksize;
 438         if (blocksize != 0)
 439                 blk_shift = int_log2(blocksize);
 440         else
 441                 blk_shift = int_log2(blksize);
 442
 443         width = int_log10(numblocks);
 444         if (width > logical_width)
 445                 logical_width = width;
 446         if (verbose)
 447                 printf("File size of %s is %llu (%llu block%s of %d bytes)\n",
 448                        filename, (unsigned long long)st.st_size,
 449                        numblocks * blksize >> blk_shift,
 450                        numblocks == 1 ? "" : "s", 1 << blk_shift);
 451
 452         if (!force_bmap) {
 453                 rc = filefrag_fiemap(fd, blk_shift, &num_extents, &st);
 454                 expected = 0;
 455         }
 456
 457         if (force_bmap || rc < 0) { /* FIEMAP failed, try FIBMAP instead */
 458                 expected = filefrag_fibmap(fd, blk_shift, &num_extents,
 459                                            &st, numblocks, is_ext2);
 460                 if (expected < 0) {
 461                         if (expected == -EINVAL || expected == -ENOTTY) {
 462                                 fprintf(stderr, "%s: FIBMAP unsupported\n",
 463                                         filename);
 464                         } else if (expected == -EPERM) {
 465                                 fprintf(stderr,
 466                                         "%s: FIBMAP requires root privileges\n",
 467                                         filename);
 468                         } else {
 469                                 fprintf(stderr, "%s: FIBMAP error: %s",
 470                                         filename, strerror(expected));
 471                         }
 472                         rc = expected;
 473                         goto out_close;
 474                 } else {
 475                         rc = 0;
 476                 }
 477                 expected = expected / data_blocks_per_cyl + 1;
 478         }
 479
 480         if (num_extents == 1)
 481                 printf("%s: 1 extent found", filename);
 482         else
 483                 printf("%s: %d extents found", filename, num_extents);
 484         /* count, and thus expected, only set for indirect FIBMAP'd files */
 485         if (is_ext2 && expected && expected < num_extents)
 486                 printf(", perfection would be %d extent%s\n", expected,
 487                         (expected > 1) ? "s" : "");
 488         else
 489                 fputc('\n', stdout);
 490 out_close:
 491         close(fd);
 492
 493         return rc;
 494 }
 495
 496 static void usage(const char *progname)
 497 {
 498         fprintf(stderr, "Usage: %s [-b{blocksize}] [-BeklsvxX] file ...\n",
 499                 progname);
 500         exit(1);
 501 }
 502
 503 int main(int argc, char**argv)
 504 {
 505         char **cpp;
 506         int rc = 0, c;
 507
 508         while ((c = getopt(argc, argv, "Bb::eksvxX")) != EOF) {
 509                 switch (c) {
 510                 case 'B':
 511                         force_bmap++;
 512                         break;
 513                 case 'b':
 514                         if (optarg) {
 515                                 char *end;
 516                                 blocksize = strtoul(optarg, &end, 0);
 517                                 if (end) {
 518                                         switch (end[0]) {
 519                                         case 'g':
 520                                         case 'G':
 521                                                 blocksize *= 1024;
 522                                                 /* no break */
 523                                         case 'm':
 524                                         case 'M':
 525                                                 blocksize *= 1024;
 526                                                 /* no break */
 527                                         case 'k':
 528                                         case 'K':
 529                                                 blocksize *= 1024;
 530                                                 break;
 531                                         default:
 532                                                 break;
 533                                         }
 534                                 }
 535                         } else { /* Allow -b without argument for compat. Remove
 536                                   * this eventually so "-b {blocksize}" works */
 537                                 fprintf(stderr, "%s: -b needs a blocksize "
 538                                         "option, assuming 1024-byte blocks.\n",
 539                                         argv[0]);
 540                                 blocksize = 1024;
 541                         }
 542                         break;
 543                 case 'e':
 544                         force_extent++;
 545                         if (!verbose)
 546                                 verbose++;
 547                         break;
 548                 case 'k':
 549                         blocksize = 1024;
 550                         break;
 551                 case 's':
 552                         sync_file++;
 553                         break;
 554                 case 'v':
 555                         verbose++;
 556                         break;
 557                 case 'x':
 558                         xattr_map++;
 559                         break;
 560                 case 'X':
 561                         ext_fmt = hex_fmt;
 562                         break;
 563                 default:
 564                         usage(argv[0]);
 565                         break;
 566                 }
 567         }
 568
 569         if (optind == argc)
 570                 usage(argv[0]);
 571
 572         for (cpp = argv + optind; *cpp != '\0'; cpp++) {
 573                 int rc2 = frag_report(*cpp);
 574
 575                 if (rc2 < 0 && rc == 0)
 576                         rc = rc2;
 577         }
 578
 579         return -rc;
 580 }
 581 #endif