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 #ifndef __linux__
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <unistd.h>
16
main(void)17 int main(void) {
18 fputs("This program is only supported on Linux!\n", stderr);
19 exit(EXIT_FAILURE);
20 }
21 #else
22 #define _LARGEFILE64_SOURCE
23
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include <unistd.h>
27 #include <string.h>
28 #include <time.h>
29 #include <fcntl.h>
30 #include <errno.h>
31 #ifdef HAVE_GETOPT_H
32 #include <getopt.h>
33 #else
34 extern char *optarg;
35 extern int optind;
36 #endif
37 #include <sys/types.h>
38 #include <sys/stat.h>
39 #include <sys/vfs.h>
40 #include <sys/ioctl.h>
41 #include <linux/fd.h>
42 #include <ext2fs/ext2_types.h>
43 #include <ext2fs/fiemap.h>
44
45 int verbose = 0;
46 int no_bs = 0; /* Don't use the files blocksize, use 1K blocksize */
47 int sync_file = 0; /* fsync file before getting the mapping */
48 int xattr_map = 0; /* get xattr mapping */
49 int force_bmap = 0;
50 int logical_width = 12;
51 int physical_width = 14;
52 unsigned long long filesize;
53
54 #define FILEFRAG_FIEMAP_FLAGS_COMPAT (FIEMAP_FLAG_SYNC | FIEMAP_FLAG_XATTR)
55
56 #define FIBMAP _IO(0x00, 1) /* bmap access */
57 #define FIGETBSZ _IO(0x00, 2) /* get the block size used for bmap */
58 #define FS_IOC_FIEMAP _IOWR('f', 11, struct fiemap)
59
60 #define EXT4_EXTENTS_FL 0x00080000 /* Inode uses extents */
61 #define EXT3_IOC_GETFLAGS _IOR('f', 1, long)
62
int_log2(int arg)63 static int int_log2(int arg)
64 {
65 int l = 0;
66
67 arg >>= 1;
68 while (arg) {
69 l++;
70 arg >>= 1;
71 }
72 return l;
73 }
74
int_log10(unsigned long long arg)75 static int int_log10(unsigned long long arg)
76 {
77 int l = 0;
78
79 arg = arg / 10;
80 while (arg) {
81 l++;
82 arg = arg / 10;
83 }
84 return l;
85 }
86
div_ceil(unsigned int a,unsigned int b)87 static unsigned int div_ceil(unsigned int a, unsigned int b)
88 {
89 if (!a)
90 return 0;
91 return ((a - 1) / b) + 1;
92 }
93
get_bmap(int fd,unsigned long block,unsigned long * phy_blk)94 static int get_bmap(int fd, unsigned long block, unsigned long *phy_blk)
95 {
96 int ret;
97 unsigned int b;
98
99 b = block;
100 ret = ioctl(fd, FIBMAP, &b); /* FIBMAP takes pointer to integer */
101 if (ret < 0) {
102 if (errno == EPERM) {
103 fprintf(stderr, "No permission to use FIBMAP ioctl; "
104 "must have root privileges\n");
105 exit(1);
106 }
107 perror("FIBMAP");
108 }
109 *phy_blk = b;
110
111 return ret;
112 }
113
print_extent_info(struct fiemap_extent * fm_extent,int cur_ex,unsigned long long expected,int blk_shift)114 static void print_extent_info(struct fiemap_extent *fm_extent, int cur_ex,
115 unsigned long long expected, int blk_shift)
116 {
117 __u64 phy_blk;
118 unsigned long long logical_blk;
119 unsigned long ext_len;
120 char flags[256] = "";
121
122 /* For inline data all offsets should be in terms of bytes, not blocks */
123 if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
124 blk_shift = 0;
125
126 ext_len = fm_extent->fe_length >> blk_shift;
127 logical_blk = fm_extent->fe_logical >> blk_shift;
128 phy_blk = fm_extent->fe_physical >> blk_shift;
129
130 if (fm_extent->fe_flags & FIEMAP_EXTENT_UNKNOWN)
131 strcat(flags, "unknown,");
132 if (fm_extent->fe_flags & FIEMAP_EXTENT_DELALLOC)
133 strcat(flags, "delalloc,");
134 if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_ENCRYPTED)
135 strcat(flags, "encrypted,");
136 if (fm_extent->fe_flags & FIEMAP_EXTENT_NOT_ALIGNED)
137 strcat(flags, "not_aligned,");
138 if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_INLINE)
139 strcat(flags, "inline,");
140 if (fm_extent->fe_flags & FIEMAP_EXTENT_DATA_TAIL)
141 strcat(flags, "tail_packed,");
142 if (fm_extent->fe_flags & FIEMAP_EXTENT_UNWRITTEN)
143 strcat(flags, "unwritten,");
144 if (fm_extent->fe_flags & FIEMAP_EXTENT_MERGED)
145 strcat(flags, "merged,");
146
147 if (fm_extent->fe_logical + fm_extent->fe_length >= filesize)
148 strcat(flags, "eof,");
149
150 /* Remove trailing comma, if any */
151 if (flags[0])
152 flags[strlen(flags) - 1] = '\0';
153
154 if (expected)
155 printf("%4d %*llu %*llu %*llu %6lu %s\n",
156 cur_ex, logical_width, logical_blk,
157 physical_width, phy_blk, physical_width, expected,
158 ext_len, flags);
159 else
160 printf("%4d %*llu %*llu %*s %6lu %s\n",
161 cur_ex, logical_width, logical_blk,
162 physical_width, phy_blk, physical_width, "",
163 ext_len, flags);
164 }
165
filefrag_fiemap(int fd,int blk_shift,int * num_extents)166 static int filefrag_fiemap(int fd, int blk_shift, int *num_extents)
167 {
168 char buf[4096] = "";
169 struct fiemap *fiemap = (struct fiemap *)buf;
170 struct fiemap_extent *fm_ext = &fiemap->fm_extents[0];
171 int count = (sizeof(buf) - sizeof(*fiemap)) /
172 sizeof(struct fiemap_extent);
173 unsigned long long last_blk = 0;
174 unsigned long flags = 0;
175 unsigned int i;
176 static int fiemap_incompat_printed;
177 int fiemap_header_printed = 0;
178 int tot_extents = 1, n = 0;
179 int last = 0;
180 int rc;
181
182 fiemap->fm_length = ~0ULL;
183
184 memset(fiemap, 0, sizeof(struct fiemap));
185
186 if (!verbose)
187 count = 0;
188
189 if (sync_file)
190 flags |= FIEMAP_FLAG_SYNC;
191
192 if (xattr_map)
193 flags |= FIEMAP_FLAG_XATTR;
194
195 do {
196 fiemap->fm_length = ~0ULL;
197 fiemap->fm_flags = flags;
198 fiemap->fm_extent_count = count;
199 rc = ioctl(fd, FS_IOC_FIEMAP, (unsigned long) fiemap);
200 if (rc < 0) {
201 if (errno == EBADR && fiemap_incompat_printed == 0) {
202 printf("FIEMAP failed with unsupported "
203 "flags %x\n", fiemap->fm_flags);
204 fiemap_incompat_printed = 1;
205 }
206 return rc;
207 }
208
209 if (verbose && !fiemap_header_printed) {
210 printf(" ext %*s %*s %*s length flags\n", logical_width,
211 "logical", physical_width, "physical",
212 physical_width, "expected");
213 fiemap_header_printed = 1;
214 }
215
216 if (!verbose) {
217 *num_extents = fiemap->fm_mapped_extents;
218 goto out;
219 }
220
221 /* If 0 extents are returned, then more ioctls are not needed */
222 if (fiemap->fm_mapped_extents == 0)
223 break;
224
225 for (i = 0; i < fiemap->fm_mapped_extents; i++) {
226 __u64 phy_blk, logical_blk;
227 unsigned long ext_len;
228
229 phy_blk = fm_ext[i].fe_physical >> blk_shift;
230 ext_len = fm_ext[i].fe_length >> blk_shift;
231 logical_blk = fm_ext[i].fe_logical >> blk_shift;
232
233 if (logical_blk && phy_blk != last_blk + 1)
234 tot_extents++;
235 else
236 last_blk = 0;
237 print_extent_info(&fm_ext[i], n, last_blk, blk_shift);
238
239 last_blk = phy_blk + ext_len - 1;
240 if (fm_ext[i].fe_flags & FIEMAP_EXTENT_LAST)
241 last = 1;
242 n++;
243 }
244
245 fiemap->fm_start = (fm_ext[i-1].fe_logical +
246 fm_ext[i-1].fe_length);
247 } while (last == 0);
248
249 *num_extents = tot_extents;
250 out:
251 return 0;
252 }
253
254 #define EXT2_DIRECT 12
255
frag_report(const char * filename)256 static void frag_report(const char *filename)
257 {
258 struct statfs fsinfo;
259 #ifdef HAVE_FSTAT64
260 struct stat64 fileinfo;
261 #else
262 struct stat fileinfo;
263 #endif
264 int bs;
265 long fd;
266 unsigned long block, last_block = 0, numblocks, i, count;
267 long bpib; /* Blocks per indirect block */
268 long cylgroups;
269 int num_extents = 0, expected;
270 int is_ext2 = 0;
271 static int once = 1;
272 unsigned int flags;
273 int rc;
274
275 #ifdef HAVE_OPEN64
276 fd = open64(filename, O_RDONLY);
277 #else
278 fd = open(filename, O_RDONLY);
279 #endif
280 if (fd < 0) {
281 perror("open");
282 return;
283 }
284
285 if (statfs(filename, &fsinfo) < 0) {
286 perror("statfs");
287 return;
288 }
289 #ifdef HAVE_FSTAT64
290 if (stat64(filename, &fileinfo) < 0) {
291 #else
292 if (stat(filename, &fileinfo) < 0) {
293 #endif
294 perror("stat");
295 return;
296 }
297 if (ioctl(fd, EXT3_IOC_GETFLAGS, &flags) < 0)
298 flags = 0;
299 if (!(flags & EXT4_EXTENTS_FL) &&
300 ((fsinfo.f_type == 0xef51) || (fsinfo.f_type == 0xef52) ||
301 (fsinfo.f_type == 0xef53)))
302 is_ext2++;
303 if (verbose && once)
304 printf("Filesystem type is: %lx\n",
305 (unsigned long) fsinfo.f_type);
306
307 cylgroups = div_ceil(fsinfo.f_blocks, fsinfo.f_bsize*8);
308 if (verbose && is_ext2 && once)
309 printf("Filesystem cylinder groups is approximately %ld\n",
310 cylgroups);
311
312 physical_width = int_log10(fsinfo.f_blocks);
313 if (physical_width < 8)
314 physical_width = 8;
315
316 if (ioctl(fd, FIGETBSZ, &bs) < 0) { /* FIGETBSZ takes an int */
317 perror("FIGETBSZ");
318 close(fd);
319 return;
320 }
321
322 if (no_bs)
323 bs = 1024;
324
325 bpib = bs / 4;
326 numblocks = (fileinfo.st_size + (bs-1)) / bs;
327 logical_width = int_log10(numblocks);
328 if (logical_width < 7)
329 logical_width = 7;
330 filesize = (long long)fileinfo.st_size;
331 if (verbose)
332 printf("File size of %s is %lld (%ld block%s, blocksize %d)\n",
333 filename, (long long) fileinfo.st_size, numblocks,
334 numblocks == 1 ? "" : "s", bs);
335 if (force_bmap ||
336 filefrag_fiemap(fd, int_log2(bs), &num_extents) != 0) {
337 for (i = 0, count = 0; i < numblocks; i++) {
338 if (is_ext2 && last_block) {
339 if (((i-EXT2_DIRECT) % bpib) == 0)
340 last_block++;
341 if (((i-EXT2_DIRECT-bpib) % (bpib*bpib)) == 0)
342 last_block++;
343 if (((i-EXT2_DIRECT-bpib-bpib*bpib) %
344 (((__u64) bpib)*bpib*bpib)) == 0)
345 last_block++;
346 }
347 rc = get_bmap(fd, i, &block);
348 if (block == 0)
349 continue;
350 if (!num_extents)
351 num_extents++;
352 count++;
353 if (last_block && (block != last_block+1) ) {
354 if (verbose)
355 printf("Discontinuity: Block %ld is at "
356 "%lu (was %lu)\n",
357 i, block, last_block+1);
358 num_extents++;
359 }
360 last_block = block;
361 }
362 }
363 if (num_extents == 1)
364 printf("%s: 1 extent found", filename);
365 else
366 printf("%s: %d extents found", filename, num_extents);
367 expected = (count/((bs*8)-(fsinfo.f_files/8/cylgroups)-3))+1;
368 if (is_ext2 && expected < num_extents)
369 printf(", perfection would be %d extent%s\n", expected,
370 (expected>1) ? "s" : "");
371 else
372 fputc('\n', stdout);
373 close(fd);
374 once = 0;
375 }
376
377 static void usage(const char *progname)
378 {
379 fprintf(stderr, "Usage: %s [-Bbvsx] file ...\n", progname);
380 exit(1);
381 }
382
383 int main(int argc, char**argv)
384 {
385 char **cpp;
386 int c;
387
388 while ((c = getopt(argc, argv, "Bbsvx")) != EOF)
389 switch (c) {
390 case 'B':
391 force_bmap++;
392 break;
393 case 'b':
394 no_bs++;
395 break;
396 case 'v':
397 verbose++;
398 break;
399 case 's':
400 sync_file++;
401 break;
402 case 'x':
403 xattr_map++;
404 break;
405 default:
406 usage(argv[0]);
407 break;
408 }
409 if (optind == argc)
410 usage(argv[0]);
411 for (cpp=argv+optind; *cpp; cpp++)
412 frag_report(*cpp);
413 return 0;
414 }
415 #endif
416