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 char *ext_fmt = "%4d: %*llu..%*llu: %*llu..%*llu: %6llu: %s\n";
  56 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                 if (errno == EPERM) {
 108                         fprintf(stderr, "No permission to use FIBMAP ioctl; "
 109                                 "must have root privileges\n");
 110                 }
 111         }
 112         *phy_blk = b;
 113
 114         return ret;
 115 }
 116
 117 static void print_extent_header(void)
 118 {
 119         printf(" ext: %*s %*s length: %*s flags:\n",
 120                logical_width * 2 + 3,
 121                "logical_offset:",
 122                physical_width * 2 + 3, "physical_offset:",
 123                physical_width + 1,
 124                "expected:");
 125 }
 126
 127 static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
 128                               unsigned long long expected, int blk_shift,
 129                               ext2fs_struct_stat *st)
 130 {
 131         unsigned long long physical_blk;
 132         unsigned long long logical_blk;
 133         unsigned long long ext_len;
 134         unsigned long long ext_blks;
 135         char flags[256] = "";
 136
 137         /* For inline data all offsets should be in bytes, not blocks */
 138         if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
 139                 blk_shift = 0;
 140
 141         ext_len = fm_extent->fe_length >> blk_shift;
 142         ext_blks = (fm_extent->fe_length - 1) >> blk_shift;
 143         logical_blk = fm_extent->fe_logical >> blk_shift;
 144         physical_blk = fm_extent->fe_physical >> blk_shift;
 145
 146         if (expected)
 147                 sprintf(flags, ext_fmt == hex_fmt ? "%*llx: " : "%*llu: ",
 148                         physical_width, expected >> blk_shift);
 149         else
 150                 sprintf(flags, "%.*s  ", physical_width, "                   ");
 151
 152         if (fm_extent->fe_flags & FIEMAP_EXTENT_UNKNOWN)
 153                 strcat(flags, "unknown,");
 154         if (fm_extent->fe_flags & FIEMAP_EXTENT_DELALLOC)
 155                 strcat(flags, "delalloc,");
 156         if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_ENCRYPTED)
 157                 strcat(flags, "encrypted,");
 158         if (fm_extent->fe_flags & FIEMAP_EXTENT_NOT_ALIGNED)
 159                 strcat(flags, "not_aligned,");
 160         if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
 161                 strcat(flags, "inline,");
 162         if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_TAIL)
 163                 strcat(flags, "tail_packed,");
 164         if (fm_extent->fe_flags & FIEMAP_EXTENT_UNWRITTEN)
 165                 strcat(flags, "unwritten,");
 166         if (fm_extent->fe_flags & FIEMAP_EXTENT_MERGED)
 167                 strcat(flags, "merged,");
 168
 169         if (fm_extent->fe_logical + fm_extent->fe_length >= st->st_size)
 170                 strcat(flags, "eof,");
 171
 172         /* Remove trailing comma, if any */
 173         if (flags[0])
 174                 flags[strlen(flags) - 1] = '\0';
 175
 176         printf(ext_fmt, cur_ex, logical_width, logical_blk,
 177                logical_width, logical_blk + ext_blks,
 178                physical_width, physical_blk,
 179                physical_width, physical_blk + ext_blks,
 180                ext_len, flags);
 181 }
 182
 183 static int filefrag_fiemap(int fd, int blk_shift, int *num_extents,
 184                            ext2fs_struct_stat *st)
 185 {
 186         char buf[16384];
 187         struct fiemap *fiemap = (struct fiemap *)buf;
 188         struct fiemap_extent *fm_ext = &fiemap->fm_extents[0];
 189         int count = (sizeof(buf) - sizeof(*fiemap)) /
 190                         sizeof(struct fiemap_extent);
 191         unsigned long long expected = 0;
 192         unsigned long flags = 0;
 193         unsigned int i;
 194         static int fiemap_incompat_printed;
 195         int fiemap_header_printed = 0;
 196         int tot_extents = 0, n = 0;
 197         int last = 0;
 198         int rc;
 199
 200         memset(fiemap, 0, sizeof(struct fiemap));
 201
 202         if (sync_file)
 203                 flags |= FIEMAP_FLAG_SYNC;
 204
 205         if (xattr_map)
 206                 flags |= FIEMAP_FLAG_XATTR;
 207
 208         do {
 209                 fiemap->fm_length = ~0ULL;
 210                 fiemap->fm_flags = flags;
 211                 fiemap->fm_extent_count = count;
 212                 rc = ioctl(fd, FS_IOC_FIEMAP, (unsigned long) fiemap);
 213                 if (rc < 0) {
 214                         if (errno == EBADR && fiemap_incompat_printed == 0) {
 215                                 printf("FIEMAP failed with unsupported "
 216                                        "flags %x\n", fiemap->fm_flags);
 217                                 fiemap_incompat_printed = 1;
 218                         }
 219                         return rc;
 220                 }
 221
 222                 /* If 0 extents are returned, then more ioctls are not needed */
 223                 if (fiemap->fm_mapped_extents == 0)
 224                         break;
 225
 226                 if (verbose && !fiemap_header_printed) {
 227                         print_extent_header();
 228                         fiemap_header_printed = 1;
 229                 }
 230
 231                 for (i = 0; i < fiemap->fm_mapped_extents; i++) {
 232                         if (fm_ext[i].fe_logical != 0 &&
 233                             fm_ext[i].fe_physical != expected) {
 234                                 tot_extents++;
 235                         } else {
 236                                 expected = 0;
 237                                 if (!tot_extents)
 238                                         tot_extents = 1;
 239                         }
 240                         if (verbose)
 241                                 print_extent_info(&fm_ext[i], n, expected,
 242                                                   blk_shift, st);
 243
 244                         expected = fm_ext[i].fe_physical + fm_ext[i].fe_length;
 245                         if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
 246                                 last = 1;
 247                         n++;
 248                 }
 249
 250                 fiemap->fm_start = (fm_ext[i - 1].fe_logical +
 251                                     fm_ext[i - 1].fe_length);
 252         } while (last == 0);
 253
 254         *num_extents = tot_extents;
 255
 256         return 0;
 257 }
 258
 259 #define EXT2_DIRECT     12
 260
 261 static int filefrag_fibmap(int fd, int blk_shift, int *num_extents,
 262                            ext2fs_struct_stat *st,
 263                            unsigned long numblocks, int is_ext2)
 264 {
 265         struct fiemap_extent    fm_ext;
 266         unsigned long           i, last_block;
 267         unsigned long long      logical;
 268                                 /* Blocks per indirect block */
 269         const long              bpib = st->st_blksize / 4;
 270         int                     count;
 271
 272         if (force_extent) {
 273                 memset(&fm_ext, 0, sizeof(fm_ext));
 274                 fm_ext.fe_flags = FIEMAP_EXTENT_MERGED;
 275         }
 276
 277         if (sync_file)
 278                 fsync(fd);
 279
 280         for (i = 0, logical = 0, *num_extents = 0, count = last_block = 0;
 281              i < numblocks;
 282              i++, logical += st->st_blksize) {
 283                 unsigned long block = 0;
 284                 int rc;
 285
 286                 if (is_ext2 && last_block) {
 287                         if (((i - EXT2_DIRECT) % bpib) == 0)
 288                                 last_block++;
 289                         if (((i - EXT2_DIRECT - bpib) % (bpib * bpib)) == 0)
 290                                 last_block++;
 291                         if (((i - EXT2_DIRECT - bpib - bpib * bpib) %
 292                              (((unsigned long long)bpib) * bpib * bpib)) == 0)
 293                                 last_block++;
 294                 }
 295                 rc = get_bmap(fd, i, &block);
 296                 if (rc < 0)
 297                         return rc;
 298                 if (block == 0)
 299                         continue;
 300                 if (*num_extents == 0) {
 301                         (*num_extents)++;
 302                         if (force_extent) {
 303                                 print_extent_header();
 304                                 fm_ext.fe_physical = block * st->st_blksize;
 305                         }
 306                 }
 307                 count++;
 308                 if (force_extent && last_block != 0 &&
 309                     (block != last_block + 1 ||
 310                      fm_ext.fe_logical + fm_ext.fe_length != logical)) {
 311                         print_extent_info(&fm_ext, *num_extents - 1,
 312                                           (last_block + 1) * st->st_blksize,
 313                                           blk_shift, st);
 314                         fm_ext.fe_logical = logical;
 315                         fm_ext.fe_physical = block * st->st_blksize;
 316                         fm_ext.fe_length = 0;
 317                         (*num_extents)++;
 318                 } else if (verbose && last_block && (block != last_block + 1)) {
 319                         printf("Discontinuity: Block %ld is at %lu (was %lu)\n",
 320                                i, block, last_block + 1);
 321                         (*num_extents)++;
 322                 }
 323                 fm_ext.fe_length += st->st_blksize;
 324                 last_block = block;
 325         }
 326
 327         if (force_extent)
 328                 print_extent_info(&fm_ext, *num_extents - 1,
 329                                   last_block * st->st_blksize, blk_shift, st);
 330
 331         return count;
 332 }
 333
 334 static void frag_report(const char *filename)
 335 {
 336         static struct statfs fsinfo;
 337         ext2fs_struct_stat st;
 338         int             blk_shift;
 339         long            fd;
 340         unsigned long   numblocks;
 341         int             data_blocks_per_cyl = 1;
 342         int             num_extents = 1, expected = ~0;
 343         int             is_ext2 = 0;
 344         static dev_t    last_device;
 345         unsigned int    flags;
 346         int             width;
 347
 348 #if defined(HAVE_OPEN64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 349         fd = open64(filename, O_RDONLY);
 350 #else
 351         fd = open(filename, O_RDONLY);
 352 #endif
 353         if (fd < 0) {
 354                 perror("open");
 355                 return;
 356         }
 357
 358 #if defined(HAVE_FSTAT64) && !defined(__OSX_AVAILABLE_BUT_DEPRECATED)
 359         if (fstat64(fd, &st) < 0) {
 360 #else
 361         if (fstat(fd, &st) < 0) {
 362 #endif
 363                 perror("stat");
 364                 return;
 365         }
 366
 367         if (last_device != st.st_dev) {
 368                 if (fstatfs(fd, &fsinfo) < 0) {
 369                         perror("fstatfs");
 370                         return;
 371                 }
 372                 if (verbose)
 373                         printf("Filesystem type is: %lx\n",
 374                                (unsigned long) fsinfo.f_type);
 375         }
 376         st.st_blksize = fsinfo.f_bsize;
 377         if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) < 0)
 378                 flags = 0;
 379         if (!(flags & EXT4_EXTENTS_FL) &&
 380             ((fsinfo.f_type == 0xef51) || (fsinfo.f_type == 0xef52) ||
 381              (fsinfo.f_type == 0xef53)))
 382                 is_ext2++;
 383
 384         if (is_ext2) {
 385                 long cylgroups = div_ceil(fsinfo.f_blocks, fsinfo.f_bsize * 8);
 386
 387                 if (verbose && last_device != st.st_dev)
 388                         printf("Filesystem cylinder groups approximately %ld\n",
 389                                cylgroups);
 390
 391                 data_blocks_per_cyl = fsinfo.f_bsize * 8 -
 392                                         (fsinfo.f_files / 8 / cylgroups) - 3;
 393         }
 394         last_device = st.st_dev;
 395
 396         width = int_log10(fsinfo.f_blocks);
 397         if (width > physical_width)
 398                 physical_width = width;
 399
 400         numblocks = (st.st_size + fsinfo.f_bsize - 1) / fsinfo.f_bsize;
 401         if (blocksize != 0)
 402                 blk_shift = int_log2(blocksize);
 403         else
 404                 blk_shift = int_log2(fsinfo.f_bsize);
 405
 406         width = int_log10(numblocks);
 407         if (width > logical_width)
 408                 logical_width = width;
 409         if (verbose)
 410                 printf("File size of %s is %llu (%lu block%s of %d bytes)\n",
 411                        filename, (unsigned long long)st.st_size,
 412                        numblocks * fsinfo.f_bsize >> blk_shift,
 413                        numblocks == 1 ? "" : "s", 1 << blk_shift);
 414
 415         if (force_bmap ||
 416             filefrag_fiemap(fd, blk_shift, &num_extents, &st) != 0) {
 417                 expected = filefrag_fibmap(fd, blk_shift, &num_extents,
 418                                            &st, numblocks, is_ext2);
 419                 if (expected < 0) {
 420                         if (errno == EINVAL || errno == ENOTTY) {
 421                                 fprintf(stderr, "%s: FIBMAP unsupported\n",
 422                                         filename);
 423                         } else if (errno != EPERM) {
 424                                 fprintf(stderr, "%s: FIBMAP error: %s",
 425                                         filename, strerror(errno));
 426                         }
 427                         goto out_close;
 428                 }
 429                 expected = expected / data_blocks_per_cyl + 1;
 430         }
 431
 432         if (num_extents == 1)
 433                 printf("%s: 1 extent found", filename);
 434         else
 435                 printf("%s: %d extents found", filename, num_extents);
 436         /* count, and thus expected, only set for indirect FIBMAP'd files */
 437         if (is_ext2 && expected && expected < num_extents)
 438                 printf(", perfection would be %d extent%s\n", expected,
 439                         (expected > 1) ? "s" : "");
 440         else
 441                 fputc('\n', stdout);
 442 out_close:
 443         close(fd);
 444 }
 445
 446 static void usage(const char *progname)
 447 {
 448         fprintf(stderr, "Usage: %s [-b{blocksize}] [-BeklsvxX] file ...\n",
 449                 progname);
 450         exit(1);
 451 }
 452
 453 int main(int argc, char**argv)
 454 {
 455         char **cpp;
 456         int c;
 457
 458         while ((c = getopt(argc, argv, "Bb::eksvxX")) != EOF)
 459                 switch (c) {
 460                 case 'B':
 461                         force_bmap++;
 462                         break;
 463                 case 'b':
 464                         if (optarg) {
 465                                 char *end;
 466                                 blocksize = strtoul(optarg, &end, 0);
 467                                 if (end) {
 468                                         switch (end[0]) {
 469                                         case 'g':
 470                                         case 'G':
 471                                                 blocksize *= 1024;
 472                                                 /* no break */
 473                                         case 'm':
 474                                         case 'M':
 475                                                 blocksize *= 1024;
 476                                                 /* no break */
 477                                         case 'k':
 478                                         case 'K':
 479                                                 blocksize *= 1024;
 480                                                 break;
 481                                         default:
 482                                                 break;
 483                                         }
 484                                 }
 485                         } else { /* Allow -b without argument for compat. Remove
 486                                   * this eventually so "-b {blocksize}" works */
 487                                 fprintf(stderr, "%s: -b needs a blocksize "
 488                                         "option, assuming 1024-byte blocks.\n",
 489                                         argv[0]);
 490                                 blocksize = 1024;
 491                         }
 492                         break;
 493                 case 'e':
 494                         force_extent++;
 495                         if (!verbose)
 496                                 verbose++;
 497                         break;
 498                 case 'k':
 499                         blocksize = 1024;
 500                         break;
 501                 case 's':
 502                         sync_file++;
 503                         break;
 504                 case 'v':
 505                         verbose++;
 506                         break;
 507                 case 'x':
 508                         xattr_map++;
 509                         break;
 510                 case 'X':
 511                         ext_fmt = hex_fmt;
 512                         break;
 513                 default:
 514                         usage(argv[0]);
 515                         break;
 516                 }
 517         if (optind == argc)
 518                 usage(argv[0]);
 519         for (cpp=argv+optind; *cpp; cpp++)
 520                 frag_report(*cpp);
 521         return 0;
 522 }
 523 #endif