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 #ifndef PATH_MAX
  48 #define PATH_MAX 4096
  49 #endif
  50
  51 static void usage(const char *prog)
  52 {
  53         fprintf(stderr, "usage: %s [-c chunksize in kb] [-h] "
  54                 "device_name\n", prog);
  55 #ifndef DEBUGFS
  56         exit(1);
  57 #endif
  58 }
  59
  60 static int ul_log2(unsigned long arg)
  61 {
  62         int     l = 0;
  63
  64         arg >>= 1;
  65         while (arg) {
  66                 l++;
  67                 arg >>= 1;
  68         }
  69         return l;
  70 }
  71
  72 static void init_chunk_info(ext2_filsys fs, struct chunk_info *info)
  73 {
  74         int i;
  75
  76         info->blocksize_bits = ul_log2((unsigned long)fs->blocksize);
  77         if (info->chunkbytes) {
  78                 info->chunkbits = ul_log2(info->chunkbytes);
  79                 info->blks_in_chunk = info->chunkbytes >> info->blocksize_bits;
  80         } else {
  81                 info->chunkbits = ul_log2(DEFAULT_CHUNKSIZE);
  82                 info->blks_in_chunk = DEFAULT_CHUNKSIZE >> info->blocksize_bits;
  83         }
  84
  85         info->min = ~0UL;
  86         info->max = info->avg = 0;
  87         info->real_free_chunks = 0;
  88
  89         for (i = 0; i < MAX_HIST; i++) {
  90                 info->histogram.fc_chunks[i] = 0;
  91                 info->histogram.fc_blocks[i] = 0;
  92         }
  93 }
  94
  95 static void update_chunk_stats(struct chunk_info *info,
  96                                unsigned long chunk_size)
  97 {
  98         unsigned long idx;
  99
 100         idx = ul_log2(chunk_size) + 1;
 101         if (idx >= MAX_HIST)
 102                 idx = MAX_HIST-1;
 103         info->histogram.fc_chunks[idx]++;
 104         info->histogram.fc_blocks[idx] += chunk_size;
 105
 106         if (chunk_size > info->max)
 107                 info->max = chunk_size;
 108         if (chunk_size < info->min)
 109                 info->min = chunk_size;
 110         info->avg += chunk_size;
 111         info->real_free_chunks++;
 112 }
 113
 114 static void scan_block_bitmap(ext2_filsys fs, struct chunk_info *info)
 115 {
 116         unsigned long long blocks_count = ext2fs_blocks_count(fs->super);
 117         unsigned long long chunks = (blocks_count + info->blks_in_chunk) >>
 118                                 (info->chunkbits - info->blocksize_bits);
 119         unsigned long long chunk_num;
 120         unsigned long last_chunk_size = 0;
 121         unsigned long long chunk_start_blk = 0;
 122         int used;
 123
 124         for (chunk_num = 0; chunk_num < chunks; chunk_num++) {
 125                 unsigned long long blk, num_blks;
 126                 int chunk_free;
 127
 128                 /* Last chunk may be smaller */
 129                 if (chunk_start_blk + info->blks_in_chunk > blocks_count)
 130                         num_blks = blocks_count - chunk_start_blk;
 131                 else
 132                         num_blks = info->blks_in_chunk;
 133
 134                 chunk_free = 0;
 135
 136                 /* Initialize starting block for first chunk correctly else
 137                  * there is a segfault when blocksize = 1024 in which case
 138                  * block_map->start = 1 */
 139                 for (blk = 0; blk < num_blks; blk++, chunk_start_blk++) {
 140                         if (chunk_num == 0 && blk == 0) {
 141                                 blk = fs->super->s_first_data_block;
 142                                 chunk_start_blk = blk;
 143                         }
 144                         used = ext2fs_fast_test_block_bitmap2(fs->block_map,
 145                                 chunk_start_blk >> fs->cluster_ratio_bits);
 146                         if (!used) {
 147                                 last_chunk_size++;
 148                                 chunk_free++;
 149                         }
 150
 151                         if (used && last_chunk_size != 0) {
 152                                 update_chunk_stats(info, last_chunk_size);
 153                                 last_chunk_size = 0;
 154                         }
 155                 }
 156
 157                 if (chunk_free == info->blks_in_chunk)
 158                         info->free_chunks++;
 159         }
 160         if (last_chunk_size != 0)
 161                 update_chunk_stats(info, last_chunk_size);
 162 }
 163
 164 #if defined(HAVE_EXT2_IOCTLS) && !defined(DEBUGFS)
 165 # define FSMAP_EXTENTS  1024
 166 static int scan_online(ext2_filsys fs, struct chunk_info *info,
 167                        blk64_t *free_blks)
 168 {
 169         struct fsmap_head *fsmap;
 170         struct fsmap *extent;
 171         struct fsmap *p;
 172         char mntpoint[PATH_MAX + 1];
 173         errcode_t retval;
 174         int mount_flags;
 175         int fd;
 176         int ret;
 177         unsigned int i;
 178
 179         /* Try to open the mountpoint for a live query. */
 180         retval = ext2fs_check_mount_point(fs->device_name, &mount_flags,
 181                                           mntpoint, PATH_MAX);
 182         if (retval) {
 183                 com_err(fs->device_name, retval, "while checking mount status");
 184                 return 0;
 185         }
 186         if (!(mount_flags & EXT2_MF_MOUNTED))
 187                 return 0;
 188         fd = open(mntpoint, O_RDONLY);
 189         if (fd < 0) {
 190                 com_err(mntpoint, errno, "while opening mount point");
 191                 return 0;
 192         }
 193
 194         fsmap = malloc(fsmap_sizeof(FSMAP_EXTENTS));
 195         if (!fsmap) {
 196                 com_err(fs->device_name, errno, "while allocating memory");
 197                 return 0;
 198         }
 199
 200         memset(fsmap, 0, sizeof(*fsmap));
 201         fsmap->fmh_count = FSMAP_EXTENTS;
 202         fsmap->fmh_keys[1].fmr_device = UINT_MAX;
 203         fsmap->fmh_keys[1].fmr_physical = ULLONG_MAX;
 204         fsmap->fmh_keys[1].fmr_owner = ULLONG_MAX;
 205         fsmap->fmh_keys[1].fmr_offset = ULLONG_MAX;
 206         fsmap->fmh_keys[1].fmr_flags = UINT_MAX;
 207
 208         *free_blks = 0;
 209         /* Fill the extent histogram with live data */
 210         while (1) {
 211                 ret = ioctl(fd, FS_IOC_GETFSMAP, fsmap);
 212                 if (ret < 0) {
 213                         com_err(fs->device_name, errno, "while calling fsmap");
 214                         free(fsmap);
 215                         return 0;
 216                 }
 217
 218                 /* No more extents to map, exit */
 219                 if (!fsmap->fmh_entries)
 220                         break;
 221
 222                 for (i = 0, extent = fsmap->fmh_recs;
 223                      i < fsmap->fmh_entries;
 224                      i++, extent++) {
 225                         if (!(extent->fmr_flags & FMR_OF_SPECIAL_OWNER) ||
 226                             extent->fmr_owner != FMR_OWN_FREE)
 227                                 continue;
 228                         update_chunk_stats(info,
 229                                            extent->fmr_length / fs->blocksize);
 230                         *free_blks += (extent->fmr_length / fs->blocksize);
 231                 }
 232
 233                 p = &fsmap->fmh_recs[fsmap->fmh_entries - 1];
 234                 if (p->fmr_flags & FMR_OF_LAST)
 235                         break;
 236                 fsmap_advance(fsmap);
 237         }
 238         free(fsmap);
 239         return 1;
 240 }
 241 #else
 242 # define scan_online(fs, info, free_blks)       (0)
 243 #endif /* HAVE_EXT2_IOCTLS */
 244
 245 static errcode_t scan_offline(ext2_filsys fs, struct chunk_info *info,
 246                               blk64_t *free_blks)
 247 {
 248         errcode_t retval;
 249
 250         *free_blks = ext2fs_free_blocks_count(fs->super);
 251         retval = ext2fs_read_block_bitmap(fs);
 252         if (retval)
 253                 return retval;
 254         scan_block_bitmap(fs, info);
 255         return 0;
 256 }
 257
 258 static errcode_t dump_chunk_info(ext2_filsys fs, struct chunk_info *info,
 259                                  FILE *f, blk64_t free_blks)
 260 {
 261         unsigned long total_chunks;
 262         const char *unitp = "KMGTPEZY";
 263         int units = 10;
 264         unsigned long start = 0, end;
 265         int i, retval = 0;
 266
 267         fprintf(f, "Total blocks: %llu\nFree blocks: %llu (%0.1f%%)\n",
 268                 (unsigned long long) ext2fs_blocks_count(fs->super),
 269                 (unsigned long long) free_blks,
 270                 (double)free_blks * 100 /
 271                 ext2fs_blocks_count(fs->super));
 272
 273         if (info->chunkbytes) {
 274                 fprintf(f, "\nChunksize: %lu bytes (%u blocks)\n",
 275                         info->chunkbytes, info->blks_in_chunk);
 276                 total_chunks = (ext2fs_blocks_count(fs->super) +
 277                                 info->blks_in_chunk) >>
 278                         (info->chunkbits - info->blocksize_bits);
 279                 fprintf(f, "Total chunks: %lu\nFree chunks: %lu (%0.1f%%)\n",
 280                         total_chunks, info->free_chunks,
 281                         (double)info->free_chunks * 100 / total_chunks);
 282         }
 283
 284         /* Display chunk information in KB */
 285         if (info->real_free_chunks) {
 286                 unsigned int scale = fs->blocksize >> 10;
 287                 info->min = info->min * scale;
 288                 info->max = info->max * scale;
 289                 info->avg = info->avg / info->real_free_chunks * scale;
 290         } else {
 291                 info->min = 0;
 292         }
 293
 294         fprintf(f, "\nMin. free extent: %lu KB \nMax. free extent: %lu KB\n"
 295                 "Avg. free extent: %lu KB\n", info->min, info->max, info->avg);
 296         fprintf(f, "Num. free extent: %lu\n", info->real_free_chunks);
 297
 298         fprintf(f, "\nHISTOGRAM OF FREE EXTENT SIZES:\n");
 299         fprintf(f, "%s :  %12s  %12s  %7s\n", "Extent Size Range",
 300                 "Free extents", "Free Blocks", "Percent");
 301         for (i = 0; i < MAX_HIST; i++) {
 302                 end = 1 << (i + info->blocksize_bits - units);
 303                 if (info->histogram.fc_chunks[i] != 0) {
 304                         char end_str[32];
 305
 306                         sprintf(end_str, "%5lu%c-", end, *unitp);
 307                         if (i == MAX_HIST-1)
 308                                 strcpy(end_str, "max ");
 309                         fprintf(f, "%5lu%c...%7s  :  %12lu  %12lu  %6.2f%%\n",
 310                                 start, *unitp, end_str,
 311                                 info->histogram.fc_chunks[i],
 312                                 info->histogram.fc_blocks[i],
 313                                 (double)info->histogram.fc_blocks[i] * 100 /
 314                                 free_blks);
 315                 }
 316                 start = end;
 317                 if (start == 1<<10) {
 318                         start = 1;
 319                         units += 10;
 320                         unitp++;
 321                 }
 322         }
 323
 324         return retval;
 325 }
 326
 327 static void close_device(char *device_name, ext2_filsys fs)
 328 {
 329         int retval = ext2fs_close_free(&fs);
 330
 331         if (retval)
 332                 com_err(device_name, retval, "while closing the filesystem.\n");
 333 }
 334
 335 static void collect_info(ext2_filsys fs, struct chunk_info *chunk_info, FILE *f)
 336 {
 337         unsigned int retval = 0;
 338         blk64_t free_blks = 0;
 339
 340         fprintf(f, "Device: %s\n", fs->device_name);
 341         fprintf(f, "Blocksize: %u bytes\n", fs->blocksize);
 342
 343         init_chunk_info(fs, chunk_info);
 344         if (!scan_online(fs, chunk_info, &free_blks)) {
 345                 init_chunk_info(fs, chunk_info);
 346                 retval = scan_offline(fs, chunk_info, &free_blks);
 347         }
 348         if (retval) {
 349                 com_err(fs->device_name, retval, "while reading block bitmap");
 350                 close_device(fs->device_name, fs);
 351                 exit(1);
 352         }
 353
 354         retval = dump_chunk_info(fs, chunk_info, f, free_blks);
 355         if (retval) {
 356                 com_err(fs->device_name, retval, "while dumping chunk info");
 357                 close_device(fs->device_name, fs);
 358                 exit(1);
 359         }
 360 }
 361
 362 #ifndef DEBUGFS
 363 static void open_device(char *device_name, ext2_filsys *fs)
 364 {
 365         int retval;
 366         int flag = EXT2_FLAG_FORCE | EXT2_FLAG_64BITS | EXT2_FLAG_THREADS;
 367
 368         retval = ext2fs_open(device_name, flag, 0, 0, unix_io_manager, fs);
 369         if (retval) {
 370                 com_err(device_name, retval, "while opening filesystem");
 371                 exit(1);
 372         }
 373         (*fs)->default_bitmap_type = EXT2FS_BMAP64_RBTREE;
 374 }
 375 #endif
 376
 377 #ifdef DEBUGFS
 378 #include "debugfs.h"
 379
 380 void do_freefrag(int argc, char **argv, int sci_idx EXT2FS_ATTR((unused)),
 381                  void *infop EXT2FS_ATTR((unused)))
 382 #else
 383 int main(int argc, char *argv[])
 384 #endif
 385 {
 386         struct chunk_info chunk_info;
 387         ext2_filsys fs = NULL;
 388         char *progname;
 389         char *end;
 390         int c;
 391
 392 #ifdef DEBUGFS
 393         if (check_fs_open(argv[0]))
 394                 return;
 395         reset_getopt();
 396 #else
 397         char *device_name;
 398
 399         add_error_table(&et_ext2_error_table);
 400 #endif
 401         progname = argv[0];
 402         memset(&chunk_info, 0, sizeof(chunk_info));
 403
 404         while ((c = getopt(argc, argv, "c:h")) != EOF) {
 405                 switch (c) {
 406                 case 'c':
 407                         chunk_info.chunkbytes = strtoull(optarg, &end, 0);
 408                         if (*end != '\0') {
 409                                 fprintf(stderr, "%s: bad chunk size '%s'\n",
 410                                         progname, optarg);
 411                                 usage(progname);
 412                         }
 413                         if (chunk_info.chunkbytes &
 414                             (chunk_info.chunkbytes - 1)) {
 415                                 fprintf(stderr, "%s: chunk size must be a "
 416                                         "power of 2.\n", argv[0]);
 417                                 usage(progname);
 418                         }
 419                         chunk_info.chunkbytes *= 1024;
 420                         break;
 421                 case 'h':
 422                 default:
 423                         usage(progname);
 424                         break;
 425                 }
 426         }
 427
 428 #ifndef DEBUGFS
 429         if (optind == argc) {
 430                 fprintf(stderr, "%s: missing device name.\n", progname);
 431                 usage(progname);
 432         }
 433
 434         device_name = argv[optind];
 435
 436         open_device(device_name, &fs);
 437 #else
 438         fs = current_fs;
 439 #endif
 440
 441         if (chunk_info.chunkbytes && (chunk_info.chunkbytes < fs->blocksize)) {
 442                 fprintf(stderr, "%s: chunksize must be greater than or equal "
 443                         "to filesystem blocksize.\n", progname);
 444                 exit(1);
 445         }
 446         collect_info(fs, &chunk_info, stdout);
 447 #ifndef DEBUGFS
 448         close_device(device_name, fs);
 449
 450         return 0;
 451 #endif
 452 }