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 {
 168         struct fsmap_head *fsmap;
 169         struct fsmap *extent;
 170         struct fsmap *p;
 171         char mntpoint[PATH_MAX + 1];
 172         errcode_t retval;
 173         int mount_flags;
 174         int fd;
 175         int ret;
 176         int i;
 177
 178         /* Try to open the mountpoint for a live query. */
 179         retval = ext2fs_check_mount_point(fs->device_name, &mount_flags,
 180                                           mntpoint, PATH_MAX);
 181         if (retval) {
 182                 com_err(fs->device_name, retval, "while checking mount status");
 183                 return 0;
 184         }
 185         if (!mount_flags & EXT2_MF_MOUNTED)
 186                 return 0;
 187         fd = open(mntpoint, O_RDONLY);
 188         if (fd < 0) {
 189                 com_err(mntpoint, errno, "while opening mount point");
 190                 return 0;
 191         }
 192
 193         fsmap = malloc(fsmap_sizeof(FSMAP_EXTENTS));
 194         if (!fsmap) {
 195                 com_err(fs->device_name, errno, "while allocating memory");
 196                 return 0;
 197         }
 198
 199         memset(fsmap, 0, sizeof(*fsmap));
 200         fsmap->fmh_count = FSMAP_EXTENTS;
 201         fsmap->fmh_keys[1].fmr_device = UINT_MAX;
 202         fsmap->fmh_keys[1].fmr_physical = ULLONG_MAX;
 203         fsmap->fmh_keys[1].fmr_owner = ULLONG_MAX;
 204         fsmap->fmh_keys[1].fmr_offset = ULLONG_MAX;
 205         fsmap->fmh_keys[1].fmr_flags = UINT_MAX;
 206
 207         /* Fill the extent histogram with live data */
 208         while (1) {
 209                 ret = ioctl(fd, FS_IOC_GETFSMAP, fsmap);
 210                 if (ret < 0) {
 211                         com_err(fs->device_name, errno, "while calling fsmap");
 212                         free(fsmap);
 213                         return 0;
 214                 }
 215
 216                 /* No more extents to map, exit */
 217                 if (!fsmap->fmh_entries)
 218                         break;
 219
 220                 for (i = 0, extent = fsmap->fmh_recs;
 221                      i < fsmap->fmh_entries;
 222                      i++, extent++) {
 223                         if (!(extent->fmr_flags & FMR_OF_SPECIAL_OWNER) ||
 224                             extent->fmr_owner != FMR_OWN_FREE)
 225                                 continue;
 226                         update_chunk_stats(info,
 227                                            extent->fmr_length / fs->blocksize);
 228                 }
 229
 230                 p = &fsmap->fmh_recs[fsmap->fmh_entries - 1];
 231                 if (p->fmr_flags & FMR_OF_LAST)
 232                         break;
 233                 fsmap_advance(fsmap);
 234         }
 235
 236         return 1;
 237 }
 238 #else
 239 # define scan_online(fs, info)  (0)
 240 #endif /* HAVE_EXT2_IOCTLS */
 241
 242 static errcode_t scan_offline(ext2_filsys fs, struct chunk_info *info)
 243 {
 244         errcode_t retval;
 245
 246         retval = ext2fs_read_block_bitmap(fs);
 247         if (retval)
 248                 return retval;
 249         scan_block_bitmap(fs, info);
 250         return 0;
 251 }
 252
 253 static errcode_t dump_chunk_info(ext2_filsys fs, struct chunk_info *info,
 254                                  FILE *f)
 255 {
 256         unsigned long total_chunks;
 257         const char *unitp = "KMGTPEZY";
 258         int units = 10;
 259         unsigned long start = 0, end;
 260         int i, retval = 0;
 261
 262         fprintf(f, "Total blocks: %llu\nFree blocks: %llu (%0.1f%%)\n",
 263                 ext2fs_blocks_count(fs->super),
 264                 ext2fs_free_blocks_count(fs->super),
 265                 (double)ext2fs_free_blocks_count(fs->super) * 100 /
 266                 ext2fs_blocks_count(fs->super));
 267
 268         if (info->chunkbytes) {
 269                 fprintf(f, "\nChunksize: %lu bytes (%u blocks)\n",
 270                         info->chunkbytes, info->blks_in_chunk);
 271                 total_chunks = (ext2fs_blocks_count(fs->super) +
 272                                 info->blks_in_chunk) >>
 273                         (info->chunkbits - info->blocksize_bits);
 274                 fprintf(f, "Total chunks: %lu\nFree chunks: %lu (%0.1f%%)\n",
 275                         total_chunks, info->free_chunks,
 276                         (double)info->free_chunks * 100 / total_chunks);
 277         }
 278
 279         /* Display chunk information in KB */
 280         if (info->real_free_chunks) {
 281                 unsigned int scale = fs->blocksize >> 10;
 282                 info->min = info->min * scale;
 283                 info->max = info->max * scale;
 284                 info->avg = info->avg / info->real_free_chunks * scale;
 285         } else {
 286                 info->min = 0;
 287         }
 288
 289         fprintf(f, "\nMin. free extent: %lu KB \nMax. free extent: %lu KB\n"
 290                 "Avg. free extent: %lu KB\n", info->min, info->max, info->avg);
 291         fprintf(f, "Num. free extent: %lu\n", info->real_free_chunks);
 292
 293         fprintf(f, "\nHISTOGRAM OF FREE EXTENT SIZES:\n");
 294         fprintf(f, "%s :  %12s  %12s  %7s\n", "Extent Size Range",
 295                 "Free extents", "Free Blocks", "Percent");
 296         for (i = 0; i < MAX_HIST; i++) {
 297                 end = 1 << (i + info->blocksize_bits - units);
 298                 if (info->histogram.fc_chunks[i] != 0) {
 299                         char end_str[32];
 300
 301                         sprintf(end_str, "%5lu%c-", end, *unitp);
 302                         if (i == MAX_HIST-1)
 303                                 strcpy(end_str, "max ");
 304                         fprintf(f, "%5lu%c...%7s  :  %12lu  %12lu  %6.2f%%\n",
 305                                 start, *unitp, end_str,
 306                                 info->histogram.fc_chunks[i],
 307                                 info->histogram.fc_blocks[i],
 308                                 (double)info->histogram.fc_blocks[i] * 100 /
 309                                 ext2fs_free_blocks_count(fs->super));
 310                 }
 311                 start = end;
 312                 if (start == 1<<10) {
 313                         start = 1;
 314                         units += 10;
 315                         unitp++;
 316                 }
 317         }
 318
 319         return retval;
 320 }
 321
 322 static void close_device(char *device_name, ext2_filsys fs)
 323 {
 324         int retval = ext2fs_close_free(&fs);
 325
 326         if (retval)
 327                 com_err(device_name, retval, "while closing the filesystem.\n");
 328 }
 329
 330 static void collect_info(ext2_filsys fs, struct chunk_info *chunk_info, FILE *f)
 331 {
 332         unsigned int retval = 0;
 333
 334         fprintf(f, "Device: %s\n", fs->device_name);
 335         fprintf(f, "Blocksize: %u bytes\n", fs->blocksize);
 336
 337         init_chunk_info(fs, chunk_info);
 338         if (!scan_online(fs, chunk_info)) {
 339                 init_chunk_info(fs, chunk_info);
 340                 retval = scan_offline(fs, chunk_info);
 341         }
 342         if (retval) {
 343                 com_err(fs->device_name, retval, "while reading block bitmap");
 344                 close_device(fs->device_name, fs);
 345                 exit(1);
 346         }
 347
 348         retval = dump_chunk_info(fs, chunk_info, f);
 349         if (retval) {
 350                 com_err(fs->device_name, retval, "while dumping chunk info");
 351                 close_device(fs->device_name, fs);
 352                 exit(1);
 353         }
 354 }
 355
 356 #ifndef DEBUGFS
 357 static void open_device(char *device_name, ext2_filsys *fs)
 358 {
 359         int retval;
 360         int flag = EXT2_FLAG_FORCE | EXT2_FLAG_64BITS;
 361
 362         retval = ext2fs_open(device_name, flag, 0, 0, unix_io_manager, fs);
 363         if (retval) {
 364                 com_err(device_name, retval, "while opening filesystem");
 365                 exit(1);
 366         }
 367         (*fs)->default_bitmap_type = EXT2FS_BMAP64_RBTREE;
 368 }
 369 #endif
 370
 371 #ifdef DEBUGFS
 372 #include "debugfs.h"
 373
 374 void do_freefrag(int argc, char **argv)
 375 #else
 376 int main(int argc, char *argv[])
 377 #endif
 378 {
 379         struct chunk_info chunk_info;
 380         ext2_filsys fs = NULL;
 381         char *progname;
 382         char *end;
 383         int c;
 384
 385 #ifdef DEBUGFS
 386         if (check_fs_open(argv[0]))
 387                 return;
 388         reset_getopt();
 389 #else
 390         char *device_name;
 391
 392         add_error_table(&et_ext2_error_table);
 393 #endif
 394         progname = argv[0];
 395         memset(&chunk_info, 0, sizeof(chunk_info));
 396
 397         while ((c = getopt(argc, argv, "c:h")) != EOF) {
 398                 switch (c) {
 399                 case 'c':
 400                         chunk_info.chunkbytes = strtoull(optarg, &end, 0);
 401                         if (*end != '\0') {
 402                                 fprintf(stderr, "%s: bad chunk size '%s'\n",
 403                                         progname, optarg);
 404                                 usage(progname);
 405                         }
 406                         if (chunk_info.chunkbytes &
 407                             (chunk_info.chunkbytes - 1)) {
 408                                 fprintf(stderr, "%s: chunk size must be a "
 409                                         "power of 2.\n", argv[0]);
 410                                 usage(progname);
 411                         }
 412                         chunk_info.chunkbytes *= 1024;
 413                         break;
 414                 case 'h':
 415                 default:
 416                         usage(progname);
 417                         break;
 418                 }
 419         }
 420
 421 #ifndef DEBUGFS
 422         if (optind == argc) {
 423                 fprintf(stderr, "%s: missing device name.\n", progname);
 424                 usage(progname);
 425         }
 426
 427         device_name = argv[optind];
 428
 429         open_device(device_name, &fs);
 430 #else
 431         fs = current_fs;
 432 #endif
 433
 434         if (chunk_info.chunkbytes && (chunk_info.chunkbytes < fs->blocksize)) {
 435                 fprintf(stderr, "%s: chunksize must be greater than or equal "
 436                         "to filesystem blocksize.\n", progname);
 437                 exit(1);
 438         }
 439         collect_info(fs, &chunk_info, stdout);
 440 #ifndef DEBUGFS
 441         close_device(device_name, fs);
 442
 443         return 0;
 444 #endif
 445 }