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 #define _LARGEFILE64_SOURCE
  24
  25 #include <stdio.h>
  26 #include <stdlib.h>
  27 #include <unistd.h>
  28 #include <string.h>
  29 #include <time.h>
  30 #include <fcntl.h>
  31 #include <errno.h>
  32 #ifdef HAVE_GETOPT_H
  33 #include <getopt.h>
  34 #else
  35 extern char *optarg;
  36 extern int optind;
  37 #endif
  38 #include <sys/types.h>
  39 #include <sys/stat.h>
  40 #include <sys/vfs.h>
  41 #include <sys/ioctl.h>
  42 #include <linux/fd.h>
  43 #include <ext2fs/ext2fs.h>
  44 #include <ext2fs/ext2_types.h>
  45 #include <ext2fs/fiemap.h>
  46
  47 int verbose = 0;
  48 int blocksize;          /* Use specified blocksize (default 1kB) */
  49 int sync_file = 0;      /* fsync file before getting the mapping */
  50 int xattr_map = 0;      /* get xattr mapping */
  51 int force_bmap; /* force use of FIBMAP instead of FIEMAP */
  52 int force_extent;       /* print output in extent format always */
  53 int logical_width = 8;
  54 int physical_width = 10;
  55 const char *ext_fmt = "%4d: %*llu..%*llu: %*llu..%*llu: %6llu: %s\n";
  56 const char *hex_fmt = "%4d: %*llx..%*llx: %*llx..%*llx: %6llx: %s\n";
  57
  58 #define FILEFRAG_FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR)
  59
  60 #define FIBMAP          _IO(0x00, 1)    /* bmap access */
  61 #define FIGETBSZ        _IO(0x00, 2)    /* get the block size used for bmap */
  62
  63 #define LUSTRE_SUPER_MAGIC 0x0BD00BD0
  64
  65 #define EXT4_EXTENTS_FL                 0x00080000 /* Inode uses extents */
  66 #define EXT3_IOC_GETFLAGS               _IOR('f', 1, long)
  67
  68 static int int_log2(int arg)
  69 {
  70         int     l = 0;
  71
  72         arg >>= 1;
  73         while (arg) {
  74                 l++;
  75                 arg >>= 1;
  76         }
  77         return l;
  78 }
  79
  80 static int int_log10(unsigned long long arg)
  81 {
  82         int     l = 0;
  83
  84         arg = arg / 10;
  85         while (arg) {
  86                 l++;
  87                 arg = arg / 10;
  88         }
  89         return l;
  90 }
  91
  92 static unsigned int div_ceil(unsigned int a, unsigned int b)
  93 {
  94         if (!a)
  95                 return 0;
  96         return ((a - 1) / b) + 1;
  97 }
  98
  99 static int get_bmap(int fd, unsigned long block, unsigned long *phy_blk)
 100 {
 101         int     ret;
 102         unsigned int b;
 103
 104         b = block;
 105         ret = ioctl(fd, FIBMAP, &b); /* FIBMAP takes pointer to integer */
 106         if (ret < 0)
 107                 return -errno;
 108         *phy_blk = b;
 109
 110         return ret;
 111 }
 112
 113 static void print_extent_header(void)
 114 {
 115         printf(" ext: %*s %*s length: %*s flags:\n",
 116                logical_width * 2 + 3,
 117                "logical_offset:",
 118                physical_width * 2 + 3, "physical_offset:",
 119                physical_width + 1,
 120                "expected:");
 121 }
 122
 123 static void print_flag(__u32 *flags, __u32 mask, char *buf, const char *name)
 124 {
 125         if ((*flags & mask) == 0)
 126                 return;
 127
 128         strcat(buf, name);
 129         *flags &= ~mask;
 130 }
 131
 132 static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
 133                               unsigned long long expected, int blk_shift,
 134                               ext2fs_struct_stat *st)
 135 {
 136         unsigned long long physical_blk;
 137         unsigned long long logical_blk;
 138         unsigned long long ext_len;
 139         unsigned long long ext_blks;
 140         __u32 fe_flags, mask;
 141         char flags[256] = "";
 142
 143         /* For inline data all offsets should be in bytes, not blocks */
 144         if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
 145                 blk_shift = 0;
 146
 147         ext_len = fm_extent->fe_length >> blk_shift;
 148         ext_blks = (fm_extent->fe_length - 1) >> blk_shift;
 149         logical_blk = fm_extent->fe_logical >> blk_shift;
 150         if (fm_extent->fe_flags & FIEMAP_EXTENT_UNKNOWN) {
 151                 physical_blk = 0;
 152         } else {
 153                 physical_blk = fm_extent->fe_physical >> blk_shift;
 154         }
 155
 156         if (expected)
 157                 sprintf(flags, ext_fmt == hex_fmt ? "%*llx: " : "%*llu: ",
 158                         physical_width, expected >> blk_shift);
 159         else
 160                 sprintf(flags, "%.*s  ", physical_width, "                   ");
 161
 162         fe_flags = fm_extent->fe_flags;
 163         print_flag(&fe_flags, FIEMAP_EXTENT_LAST, flags, "last,");
 164         print_flag(&fe_flags, FIEMAP_EXTENT_UNKNOWN, flags, "unknown_loc,");
 165         print_flag(&fe_flags, FIEMAP_EXTENT_DELALLOC, flags, "delalloc,");
 166         print_flag(&fe_flags, FIEMAP_EXTENT_ENCODED, flags, "encoded,");
 167         print_flag(&fe_flags, FIEMAP_EXTENT_DATA_ENCRYPTED, flags,"encrypted,");
 168         print_flag(&fe_flags, FIEMAP_EXTENT_NOT_ALIGNED, flags, "not_aligned,");
 169         print_flag(&fe_flags, FIEMAP_EXTENT_DATA_INLINE, flags, "inline,");
 170         print_flag(&fe_flags, FIEMAP_EXTENT_DATA_TAIL, flags, "tail_packed,");
 171         print_flag(&fe_flags, FIEMAP_EXTENT_UNWRITTEN, flags, "unwritten,");
 172         print_flag(&fe_flags, FIEMAP_EXTENT_MERGED, flags, "merged,");
 173         print_flag(&fe_flags, FIEMAP_EXTENT_SHARED, flags, "shared,");
 174         /* print any unknown flags as hex values */
 175         for (mask = 1; fe_flags != 0 && mask != 0; mask <<= 1) {
 176                 char hex[6];
 177
 178                 if ((fe_flags & mask) == 0)
 179                         continue;
 180                 sprintf(hex, "%#04x,", mask);
 181                 print_flag(&fe_flags, mask, flags, hex);
 182         }
 183
 184         if (fm_extent->fe_logical + fm_extent->fe_length >= st->st_size)
 185                 strcat(flags, "eof,");
 186
 187         /* Remove trailing comma, if any */
 188         if (flags[0] != '\0')
 189                 flags[strnlen(flags, sizeof(flags)) - 1] = '\0';
 190
 191         printf(ext_fmt, cur_ex, logical_width, logical_blk,
 192                logical_width, logical_blk + ext_blks,
 193                physical_width, physical_blk,
 194                physical_width, physical_blk + ext_blks,
 195                ext_len, flags);
 196 }
 197
 198 static int filefrag_fiemap(int fd, int blk_shift, int *num_extents,
 199                            ext2fs_struct_stat *st)
 200 {
 201         char buf[16384];
 202         struct fiemap *fiemap = (struct fiemap *)buf;
 203         struct fiemap_extent *fm_ext = &fiemap->fm_extents[0];
 204         int count = (sizeof(buf) - sizeof(*fiemap)) /
 205                         sizeof(struct fiemap_extent);
 206         unsigned long long expected = 0;
 207         unsigned long flags = 0;
 208         unsigned int i;
 209         int fiemap_header_printed = 0;
 210         int tot_extents = 0, n = 0;
 211         int last = 0;
 212         int rc;
 213
 214         memset(fiemap, 0, sizeof(struct fiemap));
 215
 216         if (sync_file)
 217                 flags |= FIEMAP_FLAG_SYNC;
 218
 219         if (xattr_map)
 220                 flags |= FIEMAP_FLAG_XATTR;
 221
 222         do {
 223                 fiemap->fm_length = ~0ULL;
 224                 fiemap->fm_flags = flags;
 225                 fiemap->fm_extent_count = count;
 226                 rc = ioctl(fd, FS_IOC_FIEMAP, (unsigned long) fiemap);
 227                 if (rc < 0) {
 228                         static int fiemap_incompat_printed;
 229                         rc = -errno;
 230                         if (rc == -EBADR && !fiemap_incompat_printed) {
 231                                 printf("FIEMAP failed with unknown flags %#x\n",
 232                                        fiemap->fm_flags);
 233                                 fiemap_incompat_printed = 1;
 234                         }
 235                         return rc;
 236                 }
 237
 238                 /* If 0 extents are returned, then more ioctls are not needed */
 239                 if (fiemap->fm_mapped_extents == 0)
 240                         break;
 241
 242                 if (verbose && !fiemap_header_printed) {
 243                         print_extent_header();
 244                         fiemap_header_printed = 1;
 245                 }
 246
 247                 for (i = 0; i < fiemap->fm_mapped_extents; i++) {
 248                         if (fm_ext[i].fe_logical != 0 &&
 249                             fm_ext[i].fe_physical != expected) {
 250                                 tot_extents++;
 251                         } else {
 252                                 expected = 0;
 253                                 if (!tot_extents)
 254                                         tot_extents = 1;
 255                         }
 256                         if (verbose)
 257                                 print_extent_info(&fm_ext[i], n, expected,
 258                                                   blk_shift, st);
 259
 260                         expected = fm_ext[i].fe_physical + fm_ext[i].fe_length;
 261                         if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
 262                                 last = 1;
 263                         n++;
 264                 }
 265
 266                 fiemap->fm_start = (fm_ext[i - 1].fe_logical +
 267                                     fm_ext[i - 1].fe_length);
 268         } while (last == 0);
 269
 270         *num_extents = tot_extents;
 271
 272         return 0;
 273 }
 274
 275 #define EXT2_DIRECT     12
 276
 277 static int filefrag_fibmap(int fd, int blk_shift, int *num_extents,
 278                            ext2fs_struct_stat *st,
 279                            unsigned long numblocks, int is_ext2)
 280 {
 281         struct fiemap_extent    fm_ext;
 282         unsigned long           i, last_block;
 283         unsigned long long      logical;
 284                                 /* Blocks per indirect block */
 285         const long              bpib = st->st_blksize / 4;
 286         int                     count;
 287
 288         if (force_extent) {
 289                 memset(&fm_ext, 0, sizeof(fm_ext));
 290                 fm_ext.fe_flags = FIEMAP_EXTENT_MERGED;
 291         }
 292
 293         if (sync_file)
 294                 fsync(fd);
 295
 296         for (i = 0, logical = 0, *num_extents = 0, count = last_block = 0;
 297              i < numblocks;
 298              i++, logical += st->st_blksize) {
 299                 unsigned long block = 0;
 300                 int rc;
 301
 302                 if (is_ext2 && last_block) {
 303                         if (((i - EXT2_DIRECT) % bpib) == 0)
 304                                 last_block++;
 305                         if (((i - EXT2_DIRECT - bpib) % (bpib * bpib)) == 0)
 306                                 last_block++;
 307                         if (((i - EXT2_DIRECT - bpib - bpib * bpib) %
 308                              (((unsigned long long)bpib) * bpib * bpib)) == 0)
 309                                 last_block++;
 310                 }
 311                 rc = get_bmap(fd, i, &block);
 312                 if (rc < 0)
 313                         return rc;
 314                 if (block == 0)
 315                         continue;
 316                 if (*num_extents == 0) {
 317                         (*num_extents)++;
 318                         if (force_extent) {
 319                                 print_extent_header();
 320                                 fm_ext.fe_physical = block * st->st_blksize;
 321                         }
 322                 }
 323                 count++;
 324                 if (force_extent && last_block != 0 &&
 325                     (block != last_block + 1 ||
 326                      fm_ext.fe_logical + fm_ext.fe_length != logical)) {
 327                         print_extent_info(&fm_ext, *num_extents - 1,
 328                                           (last_block + 1) * st->st_blksize,
 329                                           blk_shift, st);
 330                         fm_ext.fe_logical = logical;
 331                         fm_ext.fe_physical = block * st->st_blksize;
 332                         fm_ext.fe_length = 0;
 333                         (*num_extents)++;
 334                 } else if (last_block && (block != last_block + 1)) {
 335                         if (verbose)
 336                                 printf("Discontinuity: Block %ld is at %lu (was "
 337                                        "%lu)\n", i, block, last_block + 1);
 338                         (*num_extents)++;
 339                 }
 340                 fm_ext.fe_length += st->st_blksize;
 341                 last_block = block;
 342         }
 343
 344         if (force_extent)
 345                 print_extent_info(&fm_ext, *num_extents - 1,
 346                                   last_block * st->st_blksize, blk_shift, st);
 347
 348         return count;
 349 }
 350
 351 static int frag_report(const char *filename)
 352 {
 353         static struct statfs fsinfo;
 354         static unsigned int blksize;
 355         ext2fs_struct_stat st;
 356         int             blk_shift;
 357         long            fd;
 358         unsigned long long      numblocks;
 359         int             data_blocks_per_cyl = 1;
 360         int             num_extents = 1, expected = ~0;
 361         int             is_ext2 = 0;
 362         static dev_t    last_device;
 363         unsigned int    flags;
 364         int             width;
 365         int             rc = 0;
 366
 367 #if defined(HAVE_OPEN64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 368         fd = open64(filename, O_RDONLY);
 369 #else
 370         fd = open(filename, O_RDONLY);
 371 #endif
 372         if (fd < 0) {
 373                 rc = -errno;
 374                 perror("open");
 375                 return rc;
 376         }
 377
 378 #if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 379         if (fstat64(fd, &st) < 0) {
 380 #else
 381         if (fstat(fd, &st) < 0) {
 382 #endif
 383                 rc = -errno;
 384                 perror("stat");
 385                 goto out_close;
 386         }
 387
 388         if (last_device != st.st_dev) {
 389                 if (fstatfs(fd, &fsinfo) < 0) {
 390                         rc = -errno;
 391                         perror("fstatfs");
 392                         goto out_close;
 393                 }
 394                 if (ioctl(fd, FIGETBSZ, &blksize) < 0)
 395                         blksize = fsinfo.f_bsize;
 396                 if (verbose)
 397                         printf("Filesystem type is: %lx\n",
 398                                (unsigned long)fsinfo.f_type);
 399         }
 400         st.st_blksize = blksize;
 401         if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) < 0)
 402                 flags = 0;
 403         if (!(flags & EXT4_EXTENTS_FL) &&
 404             ((fsinfo.f_type == 0xef51) || (fsinfo.f_type == 0xef52) ||
 405              (fsinfo.f_type == 0xef53)))
 406                 is_ext2++;
 407
 408         if (is_ext2) {
 409                 long cylgroups = div_ceil(fsinfo.f_blocks, blksize * 8);
 410
 411                 if (verbose && last_device != st.st_dev)
 412                         printf("Filesystem cylinder groups approximately %ld\n",
 413                                cylgroups);
 414
 415                 data_blocks_per_cyl = blksize * 8 -
 416                                         (fsinfo.f_files / 8 / cylgroups) - 3;
 417         }
 418         last_device = st.st_dev;
 419
 420         width = int_log10(fsinfo.f_blocks);
 421         if (width > physical_width)
 422                 physical_width = width;
 423
 424         numblocks = (st.st_size + blksize - 1) / blksize;
 425         if (blocksize != 0)
 426                 blk_shift = int_log2(blocksize);
 427         else
 428                 blk_shift = int_log2(blksize);
 429
 430         width = int_log10(numblocks);
 431         if (width > logical_width)
 432                 logical_width = width;
 433         if (verbose)
 434                 printf("File size of %s is %llu (%llu block%s of %d bytes)\n",
 435                        filename, (unsigned long long)st.st_size,
 436                        numblocks * blksize >> blk_shift,
 437                        numblocks == 1 ? "" : "s", 1 << blk_shift);
 438
 439         if (!force_bmap) {
 440                 rc = filefrag_fiemap(fd, blk_shift, &num_extents, &st);
 441                 expected = 0;
 442         }
 443
 444         if (force_bmap || rc < 0) {
 445                 expected = filefrag_fibmap(fd, blk_shift, &num_extents,
 446                                            &st, numblocks, is_ext2);
 447                 if (expected < 0) {
 448                         if (expected == -EINVAL || expected == -ENOTTY) {
 449                                 fprintf(stderr, "%s: FIBMAP unsupported\n",
 450                                         filename);
 451                         } else if (expected == -EPERM) {
 452                                 fprintf(stderr,
 453                                         "%s: FIBMAP requires root privileges\n",
 454                                         filename);
 455                         } else {
 456                                 fprintf(stderr, "%s: FIBMAP error: %s",
 457                                         filename, strerror(expected));
 458                         }
 459                         rc = expected;
 460                         goto out_close;
 461                 } else {
 462                         rc = 0;
 463                 }
 464                 expected = expected / data_blocks_per_cyl + 1;
 465         }
 466
 467         if (num_extents == 1)
 468                 printf("%s: 1 extent found", filename);
 469         else
 470                 printf("%s: %d extents found", filename, num_extents);
 471         /* count, and thus expected, only set for indirect FIBMAP'd files */
 472         if (is_ext2 && expected && expected < num_extents)
 473                 printf(", perfection would be %d extent%s\n", expected,
 474                         (expected > 1) ? "s" : "");
 475         else
 476                 fputc('\n', stdout);
 477 out_close:
 478         close(fd);
 479
 480         return rc;
 481 }
 482
 483 static void usage(const char *progname)
 484 {
 485         fprintf(stderr, "Usage: %s [-b{blocksize}] [-BeklsvxX] file ...\n",
 486                 progname);
 487         exit(1);
 488 }
 489
 490 int main(int argc, char**argv)
 491 {
 492         char **cpp;
 493         int rc = 0, c;
 494
 495         while ((c = getopt(argc, argv, "Bb::eksvxX")) != EOF)
 496                 switch (c) {
 497                 case 'B':
 498                         force_bmap++;
 499                         break;
 500                 case 'b':
 501                         if (optarg) {
 502                                 char *end;
 503                                 blocksize = strtoul(optarg, &end, 0);
 504                                 if (end) {
 505                                         switch (end[0]) {
 506                                         case 'g':
 507                                         case 'G':
 508                                                 blocksize *= 1024;
 509                                                 /* no break */
 510                                         case 'm':
 511                                         case 'M':
 512                                                 blocksize *= 1024;
 513                                                 /* no break */
 514                                         case 'k':
 515                                         case 'K':
 516                                                 blocksize *= 1024;
 517                                                 break;
 518                                         default:
 519                                                 break;
 520                                         }
 521                                 }
 522                         } else { /* Allow -b without argument for compat. Remove
 523                                   * this eventually so "-b {blocksize}" works */
 524                                 fprintf(stderr, "%s: -b needs a blocksize "
 525                                         "option, assuming 1024-byte blocks.\n",
 526                                         argv[0]);
 527                                 blocksize = 1024;
 528                         }
 529                         break;
 530                 case 'e':
 531                         force_extent++;
 532                         if (!verbose)
 533                                 verbose++;
 534                         break;
 535                 case 'k':
 536                         blocksize = 1024;
 537                         break;
 538                 case 's':
 539                         sync_file++;
 540                         break;
 541                 case 'v':
 542                         verbose++;
 543                         break;
 544                 case 'x':
 545                         xattr_map++;
 546                         break;
 547                 case 'X':
 548                         ext_fmt = hex_fmt;
 549                         break;
 550                 default:
 551                         usage(argv[0]);
 552                         break;
 553                 }
 554
 555         if (optind == argc)
 556                 usage(argv[0]);
 557
 558         for (cpp = argv + optind; *cpp != '\0'; cpp++) {
 559                 int rc2 = frag_report(*cpp);
 560
 561                 if (rc2 < 0 && rc == 0)
 562                         rc = rc2;
 563         }
 564
 565         return rc;
 566 }
 567 #endif