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 <stdio.h>
15 #ifdef HAVE_UNISTD_H
16 #include <unistd.h>
17 #endif
18 #ifdef HAVE_STDLIB_H
19 #include <stdlib.h>
20 #endif
21 #ifdef HAVE_GETOPT_H
22 #include <getopt.h>
23 #else
24 extern char *optarg;
25 extern int optind;
26 #endif
27
28 #include "ext2fs/ext2_fs.h"
29 #include "ext2fs/ext2fs.h"
30 #include "e2freefrag.h"
31
usage(const char * prog)32 void usage(const char *prog)
33 {
34 fprintf(stderr, "usage: %s [-c chunksize in kb] [-h] "
35 "device_name\n", prog);
36 exit(1);
37 }
38
ul_log2(unsigned long arg)39 static int ul_log2(unsigned long arg)
40 {
41 int l = 0;
42
43 arg >>= 1;
44 while (arg) {
45 l++;
46 arg >>= 1;
47 }
48 return l;
49 }
50
init_chunk_info(ext2_filsys fs,struct chunk_info * info)51 void init_chunk_info(ext2_filsys fs, struct chunk_info *info)
52 {
53 int i;
54
55 info->blocksize_bits = ul_log2((unsigned long)fs->blocksize);
56 if (info->chunkbytes) {
57 info->chunkbits = ul_log2(info->chunkbytes);
58 info->blks_in_chunk = info->chunkbytes >> info->blocksize_bits;
59 } else {
60 info->chunkbits = ul_log2(DEFAULT_CHUNKSIZE);
61 info->blks_in_chunk = DEFAULT_CHUNKSIZE >> info->blocksize_bits;
62 }
63
64 info->min = ~0UL;
65 info->max = info->avg = 0;
66 info->real_free_chunks = 0;
67
68 for (i = 0; i < MAX_HIST; i++) {
69 info->histogram.fc_chunks[i] = 0;
70 info->histogram.fc_blocks[i] = 0;
71 }
72 }
73
update_chunk_stats(struct chunk_info * info,unsigned long chunk_size)74 void update_chunk_stats(struct chunk_info *info, unsigned long chunk_size)
75 {
76 unsigned long index;
77
78 index = ul_log2(chunk_size) + 1;
79 if (index >= MAX_HIST)
80 index = MAX_HIST-1;
81 info->histogram.fc_chunks[index]++;
82 info->histogram.fc_blocks[index] += chunk_size;
83
84 if (chunk_size > info->max)
85 info->max = chunk_size;
86 if (chunk_size < info->min)
87 info->min = chunk_size;
88 info->avg += chunk_size;
89 info->real_free_chunks++;
90 }
91
scan_block_bitmap(ext2_filsys fs,struct chunk_info * info)92 void scan_block_bitmap(ext2_filsys fs, struct chunk_info *info)
93 {
94 unsigned long long blocks_count = fs->super->s_blocks_count;
95 unsigned long long chunks = (blocks_count + info->blks_in_chunk) >>
96 (info->chunkbits - info->blocksize_bits);
97 unsigned long long chunk_num;
98 unsigned long last_chunk_size = 0;
99 unsigned long long chunk_start_blk = 0;
100 int used;
101
102 for (chunk_num = 0; chunk_num < chunks; chunk_num++) {
103 unsigned long long blk, num_blks;
104 int chunk_free;
105
106 /* Last chunk may be smaller */
107 if (chunk_start_blk + info->blks_in_chunk > blocks_count)
108 num_blks = blocks_count - chunk_start_blk;
109 else
110 num_blks = info->blks_in_chunk;
111
112 chunk_free = 0;
113
114 /* Initialize starting block for first chunk correctly else
115 * there is a segfault when blocksize = 1024 in which case
116 * block_map->start = 1 */
117 for (blk = 0; blk < num_blks; blk++, chunk_start_blk++) {
118 if (chunk_num == 0 && blk == 0) {
119 blk = fs->super->s_first_data_block;
120 chunk_start_blk = blk;
121 }
122 used = ext2fs_fast_test_block_bitmap(fs->block_map,
123 chunk_start_blk);
124 if (!used) {
125 last_chunk_size++;
126 chunk_free++;
127 }
128
129 if (used && last_chunk_size != 0) {
130 update_chunk_stats(info, last_chunk_size);
131 last_chunk_size = 0;
132 }
133 }
134
135 if (chunk_free == info->blks_in_chunk)
136 info->free_chunks++;
137 }
138 if (last_chunk_size != 0)
139 update_chunk_stats(info, last_chunk_size);
140 }
141
get_chunk_info(ext2_filsys fs,struct chunk_info * info)142 errcode_t get_chunk_info(ext2_filsys fs, struct chunk_info *info)
143 {
144 unsigned long total_chunks;
145 char *unitp = "KMGTPEZY";
146 int units = 10;
147 unsigned long start = 0, end, cum;
148 int i, retval = 0;
149
150 scan_block_bitmap(fs, info);
151
152 printf("Total blocks: %u\nFree blocks: %u (%0.1f%%)\n",
153 fs->super->s_blocks_count, fs->super->s_free_blocks_count,
154 (double)fs->super->s_free_blocks_count * 100 /
155 fs->super->s_blocks_count);
156
157 if (info->chunkbytes) {
158 printf("\nChunksize: %lu bytes (%u blocks)\n",
159 info->chunkbytes, info->blks_in_chunk);
160 total_chunks = (fs->super->s_blocks_count +
161 info->blks_in_chunk) >>
162 (info->chunkbits - info->blocksize_bits);
163 printf("Total chunks: %lu\nFree chunks: %lu (%0.1f%%)\n",
164 total_chunks, info->free_chunks,
165 (double)info->free_chunks * 100 / total_chunks);
166 }
167
168 /* Display chunk information in KB */
169 if (info->real_free_chunks) {
170 info->min = (info->min * fs->blocksize) >> 10;
171 info->max = (info->max * fs->blocksize) >> 10;
172 info->avg = (info->avg / info->real_free_chunks *
173 fs->blocksize) >> 10;
174 } else {
175 info->min = 0;
176 }
177
178 printf("\nMin. free extent: %lu KB \nMax. free extent: %lu KB\n"
179 "Avg. free extent: %lu KB\n", info->min, info->max, info->avg);
180
181 printf("\nHISTOGRAM OF FREE EXTENT SIZES:\n");
182 printf("%s : %12s %12s %7s\n", "Extent Size Range", "Free extents",
183 "Free Blocks", "Percent");
184 for (i = 0; i < MAX_HIST; i++) {
185 end = 1 << (i + info->blocksize_bits - units);
186 if (info->histogram.fc_chunks[i] != 0) {
187 char end_str[32];
188
189 sprintf(end_str, "%5lu%c-", end, *unitp);
190 if (i == MAX_HIST-1)
191 strcpy(end_str, "max ");
192 printf("%5lu%c...%7s : %12lu %12lu %6.2f%%\n",
193 start, *unitp, end_str,
194 info->histogram.fc_chunks[i],
195 info->histogram.fc_blocks[i],
196 (double)info->histogram.fc_blocks[i] * 100 /
197 fs->super->s_free_blocks_count);
198 }
199 start = end;
200 if (start == 1<<10) {
201 start = 1;
202 units += 10;
203 unitp++;
204 }
205 }
206
207 return retval;
208 }
209
close_device(char * device_name,ext2_filsys fs)210 void close_device(char *device_name, ext2_filsys fs)
211 {
212 int retval = ext2fs_close(fs);
213
214 if (retval)
215 com_err(device_name, retval, "while closing the filesystem.\n");
216 }
217
collect_info(ext2_filsys fs,struct chunk_info * chunk_info)218 void collect_info(ext2_filsys fs, struct chunk_info *chunk_info)
219 {
220 unsigned int retval = 0, i, free_blks;
221
222 printf("Device: %s\n", fs->device_name);
223 printf("Blocksize: %u bytes\n", fs->blocksize);
224
225 retval = ext2fs_read_block_bitmap(fs);
226 if (retval) {
227 com_err(fs->device_name, retval, "while reading block bitmap");
228 close_device(fs->device_name, fs);
229 exit(1);
230 }
231
232 init_chunk_info(fs, chunk_info);
233
234 retval = get_chunk_info(fs, chunk_info);
235 if (retval) {
236 com_err(fs->device_name, retval, "while collecting chunk info");
237 close_device(fs->device_name, fs);
238 exit(1);
239 }
240 }
241
open_device(char * device_name,ext2_filsys * fs)242 void open_device(char *device_name, ext2_filsys *fs)
243 {
244 int retval;
245 int flag = EXT2_FLAG_FORCE;
246
247 retval = ext2fs_open(device_name, flag, 0, 0, unix_io_manager, fs);
248 if (retval) {
249 com_err(device_name, retval, "while opening filesystem");
250 exit(1);
251 }
252 }
253
main(int argc,char * argv[])254 int main(int argc, char *argv[])
255 {
256 struct chunk_info chunk_info = { };
257 errcode_t retval = 0;
258 ext2_filsys fs = NULL;
259 char *device_name;
260 char *progname;
261 char c, *end;
262
263 add_error_table(&et_ext2_error_table);
264 progname = argv[0];
265
266 while ((c = getopt(argc, argv, "c:h")) != EOF) {
267 switch (c) {
268 case 'c':
269 chunk_info.chunkbytes = strtoull(optarg, &end, 0);
270 if (*end != '\0') {
271 fprintf(stderr, "%s: bad chunk size '%s'\n",
272 progname, optarg);
273 usage(progname);
274 }
275 if (chunk_info.chunkbytes &
276 (chunk_info.chunkbytes - 1)) {
277 fprintf(stderr, "%s: chunk size must be a "
278 "power of 2.\n", argv[0]);
279 usage(progname);
280 }
281 chunk_info.chunkbytes *= 1024;
282 break;
283 default:
284 fprintf(stderr, "%s: bad option '%c'\n",
285 progname, c);
286 case 'h':
287 usage(progname);
288 break;
289 }
290 }
291
292 if (optind == argc) {
293 fprintf(stderr, "%s: missing device name.\n", progname);
294 usage(progname);
295 }
296
297 device_name = argv[optind];
298
299 open_device(device_name, &fs);
300
301 if (chunk_info.chunkbytes && (chunk_info.chunkbytes < fs->blocksize)) {
302 fprintf(stderr, "%s: chunksize must be greater than or equal "
303 "to filesystem blocksize.\n", progname);
304 exit(1);
305 }
306 collect_info(fs, &chunk_info);
307 close_device(device_name, fs);
308
309 return retval;
310 }
311