misc/e2freefrag.c

   1 /*
   2  * e2freefrag - report filesystem free-space fragmentation
   3  *
   4  * Copyright (C) 2009 Sun Microsystems, Inc.
   5  *
   6  * Author: Rupesh Thakare <rupesh@sun.com>
   7  *         Andreas Dilger <adilger@sun.com>
   8  *
   9  * %Begin-Header%
  10  * This file may be redistributed under the terms of the GNU Public
  11  * License version 2.
  12  * %End-Header%
  13  */
  14 #include "config.h"
  15 #include <stdio.h>
  16 #ifdef HAVE_UNISTD_H
  17 #include <unistd.h>
  18 #endif
  19 #ifdef HAVE_STDLIB_H
  20 #include <stdlib.h>
  21 #endif
  22 #ifdef HAVE_GETOPT_H
  23 #include <getopt.h>
  24 #else
  25 extern char *optarg;
  26 extern int optind;
  27 #endif
  28 #if defined(HAVE_EXT2_IOCTLS) && !defined(DEBUGFS)
  29 # include <sys/ioctl.h>
  30 # include <sys/types.h>
  31 # include <sys/stat.h>
  32 # include <fcntl.h>
  33 # include <limits.h>
  34 #endif
  35
  36 #include "ext2fs/ext2_fs.h"
  37 #include "ext2fs/ext2fs.h"
  38 #include "e2freefrag.h"
  39
  40 #if defined(HAVE_EXT2_IOCTLS) && !defined(DEBUGFS)
  41 # ifdef HAVE_LINUX_FSMAP_H
  42 #  include <linux/fsmap.h>
  43 # endif
  44 # include "fsmap.h"
  45 #endif
  46
  47 static void usage(const char *prog)
  48 {
  49         fprintf(stderr, "usage: %s [-c chunksize in kb] [-h] "
  50                 "device_name\n", prog);
  51 #ifndef DEBUGFS
  52         exit(1);
  53 #endif
  54 }
  55
  56 static int ul_log2(unsigned long arg)
  57 {
  58         int     l = 0;
  59
  60         arg >>= 1;
  61         while (arg) {
  62                 l++;
  63                 arg >>= 1;
  64         }
  65         return l;
  66 }
  67
  68 static void init_chunk_info(ext2_filsys fs, struct chunk_info *info)
  69 {
  70         int i;
  71
  72         info->blocksize_bits = ul_log2((unsigned long)fs->blocksize);
  73         if (info->chunkbytes) {
  74                 info->chunkbits = ul_log2(info->chunkbytes);
  75                 info->blks_in_chunk = info->chunkbytes >> info->blocksize_bits;
  76         } else {
  77                 info->chunkbits = ul_log2(DEFAULT_CHUNKSIZE);
  78                 info->blks_in_chunk = DEFAULT_CHUNKSIZE >> info->blocksize_bits;
  79         }
  80
  81         info->min = ~0UL;
  82         info->max = info->avg = 0;
  83         info->real_free_chunks = 0;
  84
  85         for (i = 0; i < MAX_HIST; i++) {
  86                 info->histogram.fc_chunks[i] = 0;
  87                 info->histogram.fc_blocks[i] = 0;
  88         }
  89 }
  90
  91 static void update_chunk_stats(struct chunk_info *info,
  92                                unsigned long chunk_size)
  93 {
  94         unsigned long idx;
  95
  96         idx = ul_log2(chunk_size) + 1;
  97         if (idx >= MAX_HIST)
  98                 idx = MAX_HIST-1;
  99         info->histogram.fc_chunks[idx]++;
 100         info->histogram.fc_blocks[idx] += chunk_size;
 101
 102         if (chunk_size > info->max)
 103                 info->max = chunk_size;
 104         if (chunk_size < info->min)
 105                 info->min = chunk_size;
 106         info->avg += chunk_size;
 107         info->real_free_chunks++;
 108 }
 109
 110 static void scan_block_bitmap(ext2_filsys fs, struct chunk_info *info)
 111 {
 112         unsigned long long blocks_count = ext2fs_blocks_count(fs->super);
 113         unsigned long long chunks = (blocks_count + info->blks_in_chunk) >>
 114                                 (info->chunkbits - info->blocksize_bits);
 115         unsigned long long chunk_num;
 116         unsigned long last_chunk_size = 0;
 117         unsigned long long chunk_start_blk = 0;
 118         int used;
 119
 120         for (chunk_num = 0; chunk_num < chunks; chunk_num++) {
 121                 unsigned long long blk, num_blks;
 122                 int chunk_free;
 123
 124                 /* Last chunk may be smaller */
 125                 if (chunk_start_blk + info->blks_in_chunk > blocks_count)
 126                         num_blks = blocks_count - chunk_start_blk;
 127                 else
 128                         num_blks = info->blks_in_chunk;
 129
 130                 chunk_free = 0;
 131
 132                 /* Initialize starting block for first chunk correctly else
 133                  * there is a segfault when blocksize = 1024 in which case
 134                  * block_map->start = 1 */
 135                 for (blk = 0; blk < num_blks; blk++, chunk_start_blk++) {
 136                         if (chunk_num == 0 && blk == 0) {
 137                                 blk = fs->super->s_first_data_block;
 138                                 chunk_start_blk = blk;
 139                         }
 140                         used = ext2fs_fast_test_block_bitmap2(fs->block_map,
 141                                 chunk_start_blk >> fs->cluster_ratio_bits);
 142                         if (!used) {
 143                                 last_chunk_size++;
 144                                 chunk_free++;
 145                         }
 146
 147                         if (used && last_chunk_size != 0) {
 148                                 update_chunk_stats(info, last_chunk_size);
 149                                 last_chunk_size = 0;
 150                         }
 151                 }
 152
 153                 if (chunk_free == info->blks_in_chunk)
 154                         info->free_chunks++;
 155         }
 156         if (last_chunk_size != 0)
 157                 update_chunk_stats(info, last_chunk_size);
 158 }
 159
 160 #if defined(HAVE_EXT2_IOCTLS) && !defined(DEBUGFS)
 161 # define FSMAP_EXTENTS  1024
 162 static int scan_online(ext2_filsys fs, struct chunk_info *info)
 163 {
 164         struct fsmap_head *fsmap;
 165         struct fsmap *extent;
 166         struct fsmap *p;
 167         char mntpoint[PATH_MAX + 1];
 168         errcode_t retval;
 169         int mount_flags;
 170         int fd;
 171         int ret;
 172         int i;
 173
 174         /* Try to open the mountpoint for a live query. */
 175         retval = ext2fs_check_mount_point(fs->device_name, &mount_flags,
 176                                           mntpoint, PATH_MAX);
 177         if (retval) {
 178                 com_err(fs->device_name, retval, "while checking mount status");
 179                 return 0;
 180         }
 181         if (!mount_flags & EXT2_MF_MOUNTED)
 182                 return 0;
 183         fd = open(mntpoint, O_RDONLY);
 184         if (fd < 0) {
 185                 com_err(mntpoint, errno, "while opening mount point");
 186                 return 0;
 187         }
 188
 189         fsmap = malloc(fsmap_sizeof(FSMAP_EXTENTS));
 190         if (!fsmap) {
 191                 com_err(fs->device_name, errno, "while allocating memory");
 192                 return 0;
 193         }
 194
 195         memset(fsmap, 0, sizeof(*fsmap));
 196         fsmap->fmh_count = FSMAP_EXTENTS;
 197         fsmap->fmh_keys[1].fmr_device = UINT_MAX;
 198         fsmap->fmh_keys[1].fmr_physical = ULLONG_MAX;
 199         fsmap->fmh_keys[1].fmr_owner = ULLONG_MAX;
 200         fsmap->fmh_keys[1].fmr_offset = ULLONG_MAX;
 201         fsmap->fmh_keys[1].fmr_flags = UINT_MAX;
 202
 203         /* Fill the extent histogram with live data */
 204         while (1) {
 205                 ret = ioctl(fd, FS_IOC_GETFSMAP, fsmap);
 206                 if (ret < 0) {
 207                         com_err(fs->device_name, errno, "while calling fsmap");
 208                         free(fsmap);
 209                         return 0;
 210                 }
 211
 212                 /* No more extents to map, exit */
 213                 if (!fsmap->fmh_entries)
 214                         break;
 215
 216                 for (i = 0, extent = fsmap->fmh_recs;
 217                      i < fsmap->fmh_entries;
 218                      i++, extent++) {
 219                         if (!(extent->fmr_flags & FMR_OF_SPECIAL_OWNER) ||
 220                             extent->fmr_owner != FMR_OWN_FREE)
 221                                 continue;
 222                         update_chunk_stats(info,
 223                                            extent->fmr_length / fs->blocksize);
 224                 }
 225
 226                 p = &fsmap->fmh_recs[fsmap->fmh_entries - 1];
 227                 if (p->fmr_flags & FMR_OF_LAST)
 228                         break;
 229                 fsmap_advance(fsmap);
 230         }
 231
 232         return 1;
 233 }
 234 #else
 235 # define scan_online(fs, info)  (0)
 236 #endif /* HAVE_EXT2_IOCTLS */
 237
 238 static errcode_t scan_offline(ext2_filsys fs, struct chunk_info *info)
 239 {
 240         errcode_t retval;
 241
 242         retval = ext2fs_read_block_bitmap(fs);
 243         if (retval)
 244                 return retval;
 245         scan_block_bitmap(fs, info);
 246         return 0;
 247 }
 248
 249 static errcode_t dump_chunk_info(ext2_filsys fs, struct chunk_info *info,
 250                                  FILE *f)
 251 {
 252         unsigned long total_chunks;
 253         const char *unitp = "KMGTPEZY";
 254         int units = 10;
 255         unsigned long start = 0, end;
 256         int i, retval = 0;
 257
 258         fprintf(f, "Total blocks: %llu\nFree blocks: %u (%0.1f%%)\n",
 259                 ext2fs_blocks_count(fs->super), fs->super->s_free_blocks_count,
 260                 (double)fs->super->s_free_blocks_count * 100 /
 261                 ext2fs_blocks_count(fs->super));
 262
 263         if (info->chunkbytes) {
 264                 fprintf(f, "\nChunksize: %lu bytes (%u blocks)\n",
 265                         info->chunkbytes, info->blks_in_chunk);
 266                 total_chunks = (ext2fs_blocks_count(fs->super) +
 267                                 info->blks_in_chunk) >>
 268                         (info->chunkbits - info->blocksize_bits);
 269                 fprintf(f, "Total chunks: %lu\nFree chunks: %lu (%0.1f%%)\n",
 270                         total_chunks, info->free_chunks,
 271                         (double)info->free_chunks * 100 / total_chunks);
 272         }
 273
 274         /* Display chunk information in KB */
 275         if (info->real_free_chunks) {
 276                 unsigned int scale = fs->blocksize >> 10;
 277                 info->min = info->min * scale;
 278                 info->max = info->max * scale;
 279                 info->avg = info->avg / info->real_free_chunks * scale;
 280         } else {
 281                 info->min = 0;
 282         }
 283
 284         fprintf(f, "\nMin. free extent: %lu KB \nMax. free extent: %lu KB\n"
 285                 "Avg. free extent: %lu KB\n", info->min, info->max, info->avg);
 286         fprintf(f, "Num. free extent: %lu\n", info->real_free_chunks);
 287
 288         fprintf(f, "\nHISTOGRAM OF FREE EXTENT SIZES:\n");
 289         fprintf(f, "%s :  %12s  %12s  %7s\n", "Extent Size Range",
 290                 "Free extents", "Free Blocks", "Percent");
 291         for (i = 0; i < MAX_HIST; i++) {
 292                 end = 1 << (i + info->blocksize_bits - units);
 293                 if (info->histogram.fc_chunks[i] != 0) {
 294                         char end_str[32];
 295
 296                         sprintf(end_str, "%5lu%c-", end, *unitp);
 297                         if (i == MAX_HIST-1)
 298                                 strcpy(end_str, "max ");
 299                         fprintf(f, "%5lu%c...%7s  :  %12lu  %12lu  %6.2f%%\n",
 300                                 start, *unitp, end_str,
 301                                 info->histogram.fc_chunks[i],
 302                                 info->histogram.fc_blocks[i],
 303                                 (double)info->histogram.fc_blocks[i] * 100 /
 304                                 fs->super->s_free_blocks_count);
 305                 }
 306                 start = end;
 307                 if (start == 1<<10) {
 308                         start = 1;
 309                         units += 10;
 310                         unitp++;
 311                 }
 312         }
 313
 314         return retval;
 315 }
 316
 317 static void close_device(char *device_name, ext2_filsys fs)
 318 {
 319         int retval = ext2fs_close_free(&fs);
 320
 321         if (retval)
 322                 com_err(device_name, retval, "while closing the filesystem.\n");
 323 }
 324
 325 static void collect_info(ext2_filsys fs, struct chunk_info *chunk_info, FILE *f)
 326 {
 327         unsigned int retval = 0;
 328
 329         fprintf(f, "Device: %s\n", fs->device_name);
 330         fprintf(f, "Blocksize: %u bytes\n", fs->blocksize);
 331
 332         init_chunk_info(fs, chunk_info);
 333         if (!scan_online(fs, chunk_info)) {
 334                 init_chunk_info(fs, chunk_info);
 335                 retval = scan_offline(fs, chunk_info);
 336         }
 337         if (retval) {
 338                 com_err(fs->device_name, retval, "while reading block bitmap");
 339                 close_device(fs->device_name, fs);
 340                 exit(1);
 341         }
 342
 343         retval = dump_chunk_info(fs, chunk_info, f);
 344         if (retval) {
 345                 com_err(fs->device_name, retval, "while dumping chunk info");
 346                 close_device(fs->device_name, fs);
 347                 exit(1);
 348         }
 349 }
 350
 351 #ifndef DEBUGFS
 352 static void open_device(char *device_name, ext2_filsys *fs)
 353 {
 354         int retval;
 355         int flag = EXT2_FLAG_FORCE | EXT2_FLAG_64BITS;
 356
 357         retval = ext2fs_open(device_name, flag, 0, 0, unix_io_manager, fs);
 358         if (retval) {
 359                 com_err(device_name, retval, "while opening filesystem");
 360                 exit(1);
 361         }
 362         (*fs)->default_bitmap_type = EXT2FS_BMAP64_RBTREE;
 363 }
 364 #endif
 365
 366 #ifdef DEBUGFS
 367 #include "debugfs.h"
 368
 369 void do_freefrag(int argc, char **argv)
 370 #else
 371 int main(int argc, char *argv[])
 372 #endif
 373 {
 374         struct chunk_info chunk_info;
 375         ext2_filsys fs = NULL;
 376         char *progname;
 377         char *end;
 378         int c;
 379
 380 #ifdef DEBUGFS
 381         if (check_fs_open(argv[0]))
 382                 return;
 383         reset_getopt();
 384 #else
 385         char *device_name;
 386
 387         add_error_table(&et_ext2_error_table);
 388 #endif
 389         progname = argv[0];
 390         memset(&chunk_info, 0, sizeof(chunk_info));
 391
 392         while ((c = getopt(argc, argv, "c:h")) != EOF) {
 393                 switch (c) {
 394                 case 'c':
 395                         chunk_info.chunkbytes = strtoull(optarg, &end, 0);
 396                         if (*end != '\0') {
 397                                 fprintf(stderr, "%s: bad chunk size '%s'\n",
 398                                         progname, optarg);
 399                                 usage(progname);
 400                         }
 401                         if (chunk_info.chunkbytes &
 402                             (chunk_info.chunkbytes - 1)) {
 403                                 fprintf(stderr, "%s: chunk size must be a "
 404                                         "power of 2.\n", argv[0]);
 405                                 usage(progname);
 406                         }
 407                         chunk_info.chunkbytes *= 1024;
 408                         break;
 409                 case 'h':
 410                 default:
 411                         usage(progname);
 412                         break;
 413                 }
 414         }
 415
 416 #ifndef DEBUGFS
 417         if (optind == argc) {
 418                 fprintf(stderr, "%s: missing device name.\n", progname);
 419                 usage(progname);
 420         }
 421
 422         device_name = argv[optind];
 423
 424         open_device(device_name, &fs);
 425 #else
 426         fs = current_fs;
 427 #endif
 428
 429         if (chunk_info.chunkbytes && (chunk_info.chunkbytes < fs->blocksize)) {
 430                 fprintf(stderr, "%s: chunksize must be greater than or equal "
 431                         "to filesystem blocksize.\n", progname);
 432                 exit(1);
 433         }
 434         collect_info(fs, &chunk_info, stdout);
 435 #ifndef DEBUGFS
 436         close_device(device_name, fs);
 437
 438         return 0;
 439 #endif
 440 }